Scipedia: Documents published in 2008

Review of the use of the Department for Transport value for preventing a fatality in non road-transport systems

Scipedia content — Thu, 28 Jan 2021 19:01:18 +0100

When safety practitioners contemplate the construction of safety arguments, there is often the requirement to establish a financial measure of various accident severity classes so that cost-benefit analysis can take place on proposed mitigation efforts. Very often the method of establishing costs utilises the UK Government Department for Transport (DfT) determined benefit value for the prevention of a fatality in a road traffic accident. This is used as a marker for the accident class relating to a single fatality and a fatality accident, with a series of other values used that are based on a logarithmic to the base 10 scale. Studies and reports discussing costs and values associated with accidents have been researched and appear to indicate that the almost blind use of the DfT valuation across diverse industry systems may not be fully appropriate [e.g. 3, 4]. This paper discusses the use of the DfT value of a prevented fatality as a value for cost-benefit analysis in various industries, compares cost components of accidents in those industries, and offers guidance in determining appropriate values for analysis of proposed mitigation efforts.

Risk Assessment Education: Utilizing Interactive Video for Teaching Health and Safety

Scipedia content — Thu, 28 Jan 2021 18:57:53 +0100

Work related accidents in the construction industry are at an unacceptably high level. Better education (particularly related to re-training) across all skill levels in the industry is seen as an integral part of any solution. Traditional lecture-based courses often fail to re-create the dynamic realities of managing health and safety (H&S) on-site. They therefore do not sufficiently engage the students in deeper learning (which results in remembering and using what was learned). Interactive video appears to be one method which can aid this process by better engaging students with the material. This paper describes the development of an interactive video used to teach students about risks in setting out on-street traffic engineering experiments.

City of Phoenix Superior Pipeline PCCP Investigation and Assessment

Scipedia content — Thu, 28 Jan 2021 18:53:38 +0100

The City of Phoenix is currently in a multi-year program to investigate 150 miles of prestressed concrete cylinder pipelines (PCCP). The failure of a 60-inch pipeline focused the efforts of the investigation to a pipeline known as the Superior pipeline. The Superior pipeline is a 2.2-mile long, 29-year old pipeline that ruptured on October 3, 2006, resulting in extensive damage to the surrounding community. The pipeline was immediately shutdown and the failed section of pipeline was repaired. However, the condition of the remaining pipe and the potential for additional failures was a concern. To identify wire breaks, Pressure Pipe Inspection Company (PPIC) conducted Remote Field Transformer Coupling investigations. In addition, visual and sounding investigations were conducted by Openaka of Branchburg, New Jersey to identify internal defects. These investigations identified pipe segments that were in need of immediate repair prior to putting the pipeline back in service. This information provided baseline wire break information for the subsequent investigations. Prior to putting the pipeline back into service, 11,700 linear feet of fiber optic was installed by Pure Technologies allowing the City to acoustically monitor wire breaks in real time. This information was critical as the pipeline needed to be back in service to meet the high demand for water during the hot Phoenix summer. Real time wire break monitoring allowed the City and Brown and Caldwell to slowly resume the operation of the pipeline to prevent another failure. Monitoring of the pipeline was conducted from February 2007 through January 2008 and the pipeline was found to be extremely active with an initial average of three wire breaks occurring each day. This paper focuses on the investigations conducted and conclusive results relative to: 1) Benefits of multiple technologies for PCCP investigations, 2) Calibrated vs. non-calibrated curves for electromagnetic analysis, 3) Real time data collection through fiber optics to monitor pipeline conditions, 4) Verification of fiber optic results using electromagnetic analysis, 5) Pressure and surge monitoring.

Evaluating dynamic partial reconfiguration in the integer pipeline of a FPGA-based opensource processor

Scipedia content — Thu, 28 Jan 2021 18:44:26 +0100

This work explores the potential of sharing different arithmetic hardware operators tightly coupled to the integer pipeline of the open-source LEON3 processor. The idea is to map these modules to the same silicon area saving power consumption and area utilisation. The same strategy can be used to extend the architecture of processors optimized for applications with specific energy constraints. The proposed platform serves as a guideline to illustrate gains obtained through partial reconfiguration that need to adapt to changing standards and protocols with a limited number of resources. This work explores the potential of sharing different arithmetic hardware operators tightly coupled to the integer pipeline of the open-source LEON3 processor. The idea is to map these modules to the same silicon area saving power consumption and area utilisation. The same strategy can be used to extend the architecture of processors optimized for applications with specific energy constraints. The proposed platform serves as a guideline to illustrate gains obtained through partial reconfiguration that need to adapt to changing standards and protocols with a limited number of resources.

Generating test programs to cover pipeline interactions

Scipedia content — Thu, 28 Jan 2021 18:33:13 +0100

Functional validation of a processor design through execution of a suite of test programs is common industrial practice. In this paper, we develop a high-level architectural specification driven methodology for systematic test-suite generation. Our primary contribution is an automated test-suite generation methodology that covers all possible processor pipeline interactions. To accomplish this automation, we (1) develop a fully formal processor model based on communicating extended finite state machines, and (2) traverse the processor model for on-the-fly generation of short test programs covering all reachable states and transitions. Our test generation method achieves several orders of magnitude reduction in test-suite size compared to the previously proposed formal approaches for test generation, leading to drastic reduction in validation effort.

Consolidation of Lumpy Clay Backfill Over Buried Pipelines

Scipedia content — Thu, 28 Jan 2021 18:27:59 +0100

Offshore pipelines are usually buried to protect the pipe from external loads. When trenching is achieved by jetting or ploughing, some clayey soils can be cut into distinct lumps and this lumpy soil is then used as the backfill material under which the pipe is buried. To counter the effects of upheaval buckling, the resistance of the soil to pipe uplift must be known. There is still uncertainty about the performance of lumpy backfill in this regard. A series of centrifuge tests were performed with such soils as backfill, utilising a specially designed pore-pressure measuring pipe, to determine the influence of lump size, lump shape and pullout rate on uplift resistance Backfill comprising larger lumps consolidates quicker than if the backfill lumps are smaller. It is also observed that backfill comprising larger lumps provides greater resistance to pipe uplift after consolidation.

NextGen trajectory approaches with air-air negotiation protocol

Scipedia content — Thu, 28 Jan 2021 18:18:48 +0100

Current and future air traffic is requiring new procedures and systems to achieve a greater automation and efficiency of the air traffic operations. On controlled air space and airports, centralized ATC support the real time complexity of air traffic management. But on non-controlled aerodromes, used mainly by general aviation, the absence of ATC support may limit the increase of this type of air traffic. General aviation aircraft fly under VFR and only when weather and visibility conditions are good. Their flight is the closest approach to free flight new concept but without the technological support of avionics to make decisions. An aeronautical radio and a GPS are in most cases their available technologies on board. This paper proposes an air-air negotiation protocol for general aviation approaching an aerodrome without ATC. The technological requirement of the protocol is the aeronautical radio enhanced with an ACARS avionics. A fast decision making algorithm is proposed to solve landing time requests based on changes in speed and on the use of a same landing procedure. The protocol has been tested for several scenarios involving up to ten aircraft with satisfactory results.

Document type: Conference object

New low-power 1.5-bit time-interleaved MDAC based on MOS capacitor amplification

Scipedia content — Thu, 28 Jan 2021 18:17:42 +0100

15th IEEE International Conference on Electronics, Circuits and Systems, Malta In this paper a new time-interleaved 1.5-bit MDAC circuit is proposed. This circuit is well suited to be used in ultra low-power high-speed 4-to-8 bits pipeline ADCs. The required gain of two is implemented by switching a MOS capacitor from inversion into depletion within a clock-cycle. Low-power is achieved since no operational amplifiers are required but, instead, simple source-followers are used. Simulation results of a complete front-end stage of a 6-bit 2-channel pipeline ADC demonstrate the efficiency of the proposed technique.

Sensing Shallow Seafloor and Sediment Properties, Recent History

Scipedia content — Thu, 28 Jan 2021 18:17:16 +0100

Near surface seafloor properties are needed for recreational, commercial, and military applications. Construction projects on the ocean seafloors often require extensive knowledge about strength, deformability, hydraulic, thermal, acoustic, and seismic characteristics for locating stable environments and ensuring proper functioning of structures, pipelines, and other installations on the surface of and buried into the marine sediments. The military is also interested in a variety of seafloor properties as they impact sound propagation, mine impact burial, trafficability, bearing capacity, time-dependent settlement, and stability of objects on the seafloor. Point measurements of sediment properties are done using core samplers and sediment grab devices (with subsequent lab analysis) and in-situ probes. These techniques are expensive in terms of ship time and provide limited area coverage. Sub-bottom acoustic and electromagnetic sensors can provide profiles of near surface sediment information with improved coverage rates. Fusion techniques are being developed to provide areal extent of sediment information from multiple sensors. This paper examines the recent history of techniques used to measure sediment properties in the upper portions of the seafloor and in shallow ("100m) water.

Comment: Oceans '08 MTS/IEEE Quebec, (Oceans, Poles and Climate: Technological Challenges) 15-18 September, 2008

Long-run marginal cost in the RoRo industry

Scipedia content — Thu, 28 Jan 2021 18:17:05 +0100

In this article a quantitative analysis of the cost structure a shipping company has to take into account when starting and running a regular Ro-Ro cargo line (a Short Sea Shipping line, for instance) is carried out. The object of this paper is to study Ro-Ro industry. However, Ro-Pax vessels cannot be excluded. Their behaviour when analysing the exploitation costs is very similar to Ro-Ro vessel’s, and it cannot be forgotten that nowadays most of the Ro-Ro vessels carry passengers as well. The empirical data used to formulate this paper are based on the Spanish market and the current Mediterranean lines. The aim of this paper is to find an expression for the total costs depending on the parameters of the analyzed route, bearing in mind that the vessel’s capacity will be an important factor. This model will be applied to rolled cargo vessels, especially trucks or platforms. Once the costs function is obtained the long run marginal costs will also be obtained, depending on the line capacity, aiming to obtain the optimum pricing, according to microeconomic theory. Frequency and regularity reflected upon the amount of scales will also be considered to be important because the long run marginal costs will depend on the amount of scales and the amount of transported platforms/trucks.

Analysis of sensor and fusion schedules of a time-triggered sensor fusion system

Scipedia content — Thu, 28 Jan 2021 18:15:21 +0100

In this paper we analyze the sensor and fusion schedules of a time-triggered, Kalman filter based, multi-sensor fusion system. The fusion system is used as an environmental perception platform for advanced driver assistance systems and delivers its service to a safety related application. As the application demands cyclic updates with bounded accuracy, the influence of the sensor and fusion schedules on the service accuracy is analysed, which enables us to optimize the system without model dependent simulations.

Evaluation of the travel demand and proper solution suggestion for developing public bus transport: a case study in Ahwaz city

Scipedia content — Thu, 28 Jan 2021 18:08:36 +0100

This paper on developing public bus transit is from the proceedings of 14th International Conference on Urban Transport and the Environment in the 21st Century, which was held in Malta in 2008. The authors described the evaluation of the travel demand and suggest a proper solution for developing public bus transport in Ahwaz city in Iran. They focus on problems with the present public bus transportation in Ahwaz city and how to evaluate bus travel demand by using population data. The paper also offers three methods that can be used to determine the number of transit vehicles needed for solving passenger transport demand. The authors conclude that the determination of the optimal route is the most important step in planning optimal bus system and should include proper spread network rules, minimum lapping of lines, absence of concentration of lines in one zone, and proper line numbers.

Asynchronous Linear Pipelines: An Efficient-Optimal Pipelining Algorithm

Scipedia content — Thu, 28 Jan 2021 17:47:04 +0100

ISBN : 978-1-4244-2182-4; International audience; This paper introduces a new methodology for optimizing the performance of Asynchronous-Linear Pipelines. The method supports all delay types, static and variable time delays, enabling the designers to optimize their architecture taking into account the timing information of data dependencies, circuit structure and process variations. The method not only determines the minimum degree of pipelining necessary to satisfy a given performance target, but also computes the optimum placement of the pipeline stages to maximize the throughput.

FAST: Future airport strategies

Scipedia content — Thu, 28 Jan 2021 17:46:33 +0100

International audience; During the last decade the air transport market was marked by the emergence and development of the low cost carriers (LCCs). The LCCs market share in Europe was indeed multiplied by 3 in 4 years, going from 5% in 2002 to 16% in 2006. This major change in the air transport market has strongly contributed to the trend towards privatization of airport ownership and management. One main result of such changes is the development of airports? new strategies to increase their attractiveness and their competitiveness. In this context, it is particularly relevant to focus on airport strategies and their future evolution. Which type of airport will be concerned by these strategies? Will new trends in airport strategies appear? What could be the impact of airport strategies development on the traffic distribution at airports? The FAST project aims at providing answers to these questions by analyzing the potential evolution of airport strategies in the next decade according to a defined typology of airports and by analyzing the potential impacts of such future strategies on traffic distribution at airports. The project is decomposed in three work-packages.

Traffic Analysis and Synthetic Scenario Generation for ATM Operational Concepts Evaluation

Scipedia content — Thu, 28 Jan 2021 17:27:32 +0100

This paper describes a pair of systems which can be used to obtain realistic traffic samples in a Sector/TMA from a given real traffic database. Those are a traffic analyzer and a traffic pattern generator. These two systems allow the ATM engineer to both gain insight on the traffic structure of the area under analysis and to obtain statistically significant samples for the evaluation of operational concepts and procedure changes, perform analysis of ATM performance under traffic changes, ...

Document type: Conference object

Efficiency improvement in autonomous electric vehicles using dynamic commutation of energy resources.

Scipedia content — Thu, 28 Jan 2021 17:23:02 +0100

Multi Hour Robust Routing and Fast Load Change Detection for Traffic Engineering

Scipedia content — Thu, 28 Jan 2021 17:03:39 +0100

Traffic Engineering (TE) has become a challenging mechanism for network management and resources optimization due to the uncertainty and the difficulty to predict current traffic patterns. Recent works have proposed robust optimization techniques to cope with uncertain traffic, computing a stable routing configuration that is immune to demand variations within certain uncertainty set. However, using a single routing configuration for long-time periods can be highly inefficient. Even more, the presence of abnormal and malicious traffic has magnified the network operation problem, claiming for solutions which not only deal with traffic uncertainty but also allow to identify faulty traffic. In this paper, we propose two complementary methods to tackle both problems. Based on expected traffic patterns, we adapt the uncertainty set and build a multi-hour yet robust routing scheme that outperforms the stable approach. For the case of anomalous and unexpected traffic, we propose a fast anomaly detection/isolation algorithm which relies on a novel linear spline-based model of traffic demands to identify traffic problems and decide routing changes. This algorithm is optimal in the sense that it minimizes the decision delay for a given mean false alarm rate and false isolation probabilities. Both proposals are validated using real traffic data from two Internet backbone networks.

Anemone : a ready-to-go testbed for IPv6 compliant intelligent transport systems

Scipedia content — Thu, 28 Jan 2021 17:02:34 +0100

This paper presents the tools that have been developed in the IST-Anemone project, a large European testbed deployed for testing and validating IPv6 mobility protocols and products. The testbed is available to third parties, which may include research projects and companies seeking to validate IPv6-ready products. "br/"This tested is particularly suitable for ITS experimentation as it includes several private roads and various network access technologies, IPv6 mobility support and a set of tools for testing IPv6 and performing demonstrations. "br/"Several ITS-related experiments have been performed by Anemone partners.

Trafik Tıkanıklığı Yönetimi Olarak Fiyatlandırma Ve İstanbul-eminönü İçin Bir Uygulama

Scipedia content — Tue, 26 Jan 2021 18:04:37 +0100

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2009

Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2009

Bu çalışmada, tıkanıklık fiyatlandırmasının İstanbul’da uygulanabilirliğinin araştırılması amacıyla, Eminönü bölgesi için bir fiyatlandırma modeli oluşturulmuştur. Eminönü ilçesi, küçük yüzölçümüne bağlı olarak görece dar yol ağına ve son derece iyi tanımlanmış sınırlara sahip olmasının yanında, üç tarafının denizlerle çevrili olması ile bir fiyatlandırma uygulaması için aranan özelliklere sahiptir. Bölge, barındırdığı tarihi, kültürel ve idari yapılar sebebiyle önemli bir ulaşım talebine yol açmaktadır. Trafik akımına ait büyüklüklerin zamanda değişmediğinin kabul edildiği bu model kapsamında yapılan analizlerde, Eminönü bölgesi yol ağının tamamı için, ulaştırma ekonomisi prensipleri paralelinde, ortalama maliyet, marjinal maliyet ve talep eğrileri elde edilmiştir. Maliyet eğrileri trafik akımının temel değişkenleri arasındaki ilişkiden hareketle belirlenirken; talep eğrisini elde etmek için özel otomobil ve toplu taşıma türlerini içeren bir tür tercihi modeli oluşturulmuştur. Sosyal optimumunu sağlayacak fiyat ise maliyet eğrileri ile talep eğrisinin kesişim noktalarında ortaya çıkan denge durumlarına bağlı olarak hesaplanmıştır. Model sonuçları, fiyatlandırma uygulaması ile özel otomobil kullanıcılarının sayısında ciddi bir azalma sağlanmasının ve özel otomobillerini kullanmaya devam eden kullanıcılardan önemli bir gelir elde edilmesinin mümkün olduğunu göstermiştir.

This study evaluates the applicability of congestion pricing in Istanbul with the help of a congestion pricing model developed for the district of Eminonu. Several qualities of the district are favourable for a congestion pricing scheme: The district is a peninsula, has well defined borders and a less complicated road network compared with other districts of the city. Furthermore, the demand of trips to Eminonu is very high due to the existence of many historic, cultural and administrative structures. Eminonu congestion pricing model is a static model that assumes the traffic variables unchanging throughout the analysis. Calculations of the model include determining the average cost, the marginal cost and the demand curves that represent the whole road network of the district, and the socially optimum price value. The cost curves are obtained by using the relationship between the basic variables of traffic whereas the demand curve is determined by estimating a binary mode-choice model for public transport and private vehicle modes. The socially optimum price is calculated according to the equilibrium points that constitute where cost curves and the demand curve intersect. The results of the model present a significant amount of shift of private vehicle users to other transportation modes because of congestion pricing. Besides, the implementation has a great potential to generate substantial amount of revenues collected from opting-not-to-change users.

Doktora

PhD

Modeling noise annoyance caused by air traffic using fuzzy logic

Scipedia content — Tue, 26 Jan 2021 18:02:45 +0100

The main goal of this project is the study and modeling of the noise annoyance caused by air traffic by using the fuzzy logic theory. Like many other environmental problems, air traffic noise, continues to grow and has become a serious problem in many countries. Millions of people living or working around airport areas can suffer from noise exposure effects as for instance hearing loss, interference with communication, stress, sleep disturbance, psychological effects as well as a general reduction in quality of life and tranquillity. However, noise annoyance is a difficult issue to evaluate as it is open to subjective reactions. Fuzzy logic theory is the perfect tool to analyse and evaluate all that vague and imprecise concepts that contrary to many other concepts, like age, distance or time, can not be measured as easily. In this project, a fuzzy function has been developed to quantify the annoyance level that people living or working in areas near airports are suffering. The parameters that come into play in this feature are the noise level, time of day, the number of events per hour, and finally, if it is a residential or an industrial area. Finally, the results of the fuzzy system have been represented on graphics that show the levels of nuisance caused by aircraft noise in each of the situations according the variables of the fuzzy function.

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Scipedia content — Tue, 26 Jan 2021 18:01:49 +0100

Service providers must understand that they have to provide customer-perceived value, if they want to stay in business. One of the best ways to determine customer-perceived value is to encourage customer complaint. This will make it easier to identify areas of the service process which the consumer believes must be improved. The ultimate goal of our thesis is to identify and establish the patterns of customer complaint behaviour in public transportation which is a part of the service sector. If patterns are identified, it will be much easier to encourage and predict customers‘ abilities and willingness to complain during a service process. Hence, service providers will be able to create an environment that can encourage and facilitate customer complaint processes. In this regard, service providers will obtain more information that will enable them to improve the quality of their services in order provide customer-perceived value. In addition, due to the fact that services are offered at the same time when the customer is there, this increases chances of customers seeing failures. Therefore, it is vital to make it easier for customers to be able to complain as soon as they perceive these failures so that they leave the service environment satisfied. Thus, understanding the pattern of customer complaint behaviour will make this process easier. By pattern, we mean sequence and therefore, there must be factors that influence this sequence. Our thesis shall focus on three main factors; cost, contextual resources and customer‘s competence, that influence the ability, willingness and the extent to which customers will engage in a complain process. Therefore, this thesis focuses on the following: What is the pattern of customer complaint behaviour in public transportation and how do cost, contextual resources and customer‘s competence impact this pattern?However, we shall also mention other external factors that may influence the pattern of customer complaint behaviour like market structure and service characteristics. It is imperative to understand customer complaint behaviour in service because through customer complaint, customers‘ quality expectations can be determined and met. Studies reveal that, although complaint channels may exist, some customers still do not complaint. In our survey, only 21.6% of respondents who encountered a service failure actually complained implying that 78.4% of the respondents who encountered an unfavourable service experience did not complain. What could be the reasons that customers who encounter problems do not complaint, although they would want to complain?2Above all, if there is something to be learnt from customer complaint behaviour, we think that it should be the patterns of customer complaint behaviour. This is because if patterns can be identified, then the right channels can be put in place by service providers in order to encourage and facilitate the complaint process. This will enable much information to be obtained from the customers and then used to make improvements in the service offerings and processes. In this regard service quality and customer satisfaction can be increased. This will lead to customer retention and higher profits for the company as well as prevent negative word-of-mouth.In this thesis, we identified patterns of customer complaint behaviour in service with a focus in public transportation by using data from the passengers of the public bus companies of Karlstad city and the intercity bus company (SWEBUS) as bases of our research. In our questionnaire we asked customers to indicate the strength of preference for a complaint channel they would use in order to make a complaint to the bus company in the event of a negative service experience. The results were ranked in order to determine the pattern of customer complaint behaviour in public transportation. We approached this topic by revealing the importance of understanding customer complaint behaviour and using this knowledge to improve service development. We proceeded by emphasising on the importance of viewing customer complaint behaviour from the perspective of service dominant logic. The Service and Market Oriented Transport Research Grou

Electric Bicycle Design

Scipedia content — Tue, 26 Jan 2021 17:56:54 +0100

The thesis consists of the design of an electric bike. Based on the analysis of the needs arising from urban transport in Sweden and its people.We wanted to develop a bicycle that could be manufactured in the coming years and be widely accepted by the Swedish population and later also in Europe.

Transport Planning and Sustainability : The Via Baltica Case

Scipedia content — Tue, 26 Jan 2021 17:24:09 +0100

Road transport is most commonly used out of other modes in terms of freight and passenger transportation on local and regional levels. For European citizens it is a primary mean of their access to services, social activities and employment. The scope of road infrastructure differs in some regions. The major disparity appears when the East of Europe is compared with the West. Actions to link periphery with the core of Europe are being continuously performed, what in this case represents itself in constructing Pan-European Transport Corridors, which will contribute to the connection of the whole territory of Europe. The Via Baltica, chosen as a case for this thesis, is a route to connect Helsinki, Tallinn, Riga, Kaunas, Budzisko and Warsaw. It is the common initiative of Finland, Estonia, Lithuania, Latvia and Poland. In addition, it is to be an express road and part of the I Pan-European Transport Corridor, which is going to connect Baltic countries with the West and South part of Europe. We focus on presenting how the Via Baltica is introduced in official documents and compare it with the process in practice. Our final goal is to assess the planning process of the Via Baltica route in Poland according to top down planning approaches and sustainability criteria. We are trying to find out what are the advantages and disadvantages of the ongoing process. After introducing results of the analysis made for the Via Baltica by Polish experts, we present how stakeholders and local authorities try to reinforce the process, regardless of environmental issues, to achieve economic and social profits. As the result we try find out how are the dimensions of sustainable development handled in the Via Baltica case in Poland. The conclusions are based on our findings concerning several conflicts which appeared during the planning process. They are also based on one-dimension as well as multi-criteria analyses. angelikakowalczyk@o2.pl monika.m.kustra@gmail.com

A configuration of the urban space of São Paulo municipality through the itinerary of bus networks, their sceneries and memories of itinerants (1960-1985)

Scipedia content — Tue, 26 Jan 2021 17:18:07 +0100

o longo das décadas de 60, 70 e 80, houve um crescimento da taxa de desemprego, em virtude da instalação dos novos arranjos industriais, que conduziram centenas de milhares de trabalhadores a buscar outros postos de trabalho, seja por meio de reciclagem profissional ou economia informal. Esse deslocamento no mercado de trabalho só é viável caso tenha à disposição transporte individual ou coletivo. Esta mercantilização do espaço urbano apontou para um movimento centro-periferia. Este deslocamento se relaciona com a desconcentração espacial e do trabalho e das empresas e centralização do capital. Estes processos incidiram de forma determinante nos serviços de transportes públicos, principalmente por ônibus. Eles mudaram conseqüentemente a configuração da paisagem e do espaço urbano do município de São Paulo. Este fato obrigou centenas de milhares de usuários de transportes coletivos a se adaptarem às novas rotas de comércio, de trabalho, de residências e itinerários de ônibus e de vida, para sobreviverem. Quando desaparecem os lugares socialmente construídos, (residências, praças, ruas, etc), estes se tornam parte das memórias dos habitantes. Tais registros de reminiscências, quando são resgatados, se cristalizam com a construção de uma História local, que se tece por meio das relações materiais de ontem e com as relações afetivas dos homens. The installation of new industrial settlements generated - throughout the decades of 1960, 1970 and 1980 - a growth in the rate of unemployment which may have compelled thousand of hundreds of workers to search for other workplaces. This happened into job recycling or assuming informal activities. Such a displacing in the market labor may only be feasible if there were at disposal public and /or individual transportation. Thus, a commercialization of the urban space succeeded in pointing to a centerperipheral movement. The displacement through the urban areas relates to space of decentralization of plants and labor and of the concentration of the capital. Such processes acted to building a new configuration of the urban transportation services, mainly bus services. They consequently changed the sceneries and the urban spaces of São Paulo town and environment. Such a fact compelled thousand of hundreds of transportation users to adapt to new routes of commerce, of work, of neighborhood so as bus itineraries, in order to maintain their incomes. The places socially constructed by the workers remain only in their memories after they are physically ruined. They become part of the memory of the inhabitants. A part of these memory are here brought back as a register of a Local History, that is woven through material relations in the past of the men and their present-day fondness.

Collaborative En Route Airspace Management Considering Stochastic Demand, Capacity, and Weather Conditions

Scipedia content — Tue, 26 Jan 2021 16:23:34 +0100

The busiest regions of airspace in the U.S. are congested during much of the day from traffic volume, weather, and other airspace restrictions. The projected growth in demand for airspace is expected to worsen this congestion while reducing system efficiency and safety. This dissertation focuses on providing methods to analyze en route airspace congestion during severe convective weather (i.e. thunderstorms) in an effort to provide more efficient aircraft routes in terms of: en route travel time, air traffic controller workload, aircraft collision potential, and equity between airlines and other airspace users. The en route airspace is generally that airspace that aircraft use between the top of climb and top of descent. Existing en route airspace flight planning models have several important limitations. These models do not appropriately consider the uncertainty in airspace demand associated with departure time prediction and en route travel time. Also, airspace capacity is typically assumed to be a static value with no adjustments for weather or other dynamic conditions that impact the air traffic controller. To overcome these limitations a stochastic demand, stochastic capacity, and an incremental assignment method are developed. The stochastic demand model combines the flight departure uncertainty and the en route travel time uncertainty to achieve better estimates for sector demand. This model is shown to reduce the predictive error for en route sector demand by 20\\% at a 30 minute look-ahead time period. The stochastic capacity model analyzes airspace congestion at a more macroscopic level than available in existing models. This higher level of analysis has the potential to reduce computational time and increase the number of alternative routing schemes considered. The capacity model uses stochastic geometry techniques to develop predictions of the distribution of flight separation and conflict potential. A prediction of dynamic airspace capacity is calculated based on separation and conflict potential. The stochastic demand and capacity models are integrated into a graph theoretic framework to generate alternative routing schemes. Validation of the overall integrated model is performed using the fast time airspace simulator RAMS. The original flight plans, the routing obtained from an integer programming method, and the routing obtained from the incremental method developed in this dissertation are compared. Results of this validation simulation indicate that integer programming and incremental routing methods are both able to reduce the average en route travel time per flight by 6 minutes. Other benefits include a reduction in the number of conflict resolutions and weather avoidance maneuvers issued by en route air traffic controllers. The simulation results do not indicate a significant difference in quality between the incremental and integer programming methods of routing flights around severe weather. Ph. D.

Traffic Accident Prediction Model Implementation in Traffic Safety Management

Scipedia content — Tue, 26 Jan 2021 16:16:01 +0100

one of the highest fatalities causes, traffic accidents and collisions always requires a large amounteffort to be reduced or prevented from occur. Traffic safety management routines therefore always needefficient and effective implementation due to the variations of traffic, especially from trafficengineering point of view apart from driver education.Traffic Accident Prediction Model, considered as one of the handy tool of traffic safety management,has become of well followed with interested. Although it is believed that traffic accidents are mostlycaused by human factors, these accident prediction models would help from traffic engineering point ofview to enlarge the traffic safety level of road segments. This thesis is aiming for providing a guidelineof the accident prediction model implementation in traffic safety management, regarding to trafficengineering field. Discussion about how this prediction models should merge into the existing routinesand how well these models would perform would be given. As well, cost benefit analysis of theimplementation would be at the end of this thesis. Meanwhile, a practical field study would bepresented in order to show the procedures of the implementation of traffic accident prediction model.The field study is about this commercial model set SafeNET, from TRL Limited UK, implemented inRoad Safety Audit procedures combined with microscopic simulation tool. Detailed processing andinput and output data will be given accompany with the countermeasures for accident frequencyreduction finalization.

Developing link capacity functions at urban arterials

Scipedia content — Tue, 26 Jan 2021 16:00:38 +0100

Thesis (Master)--Izmir Institute of Technology, City and Regional Planning, Izmir, 2009

Includes bibliographical references (leaves: 67)

Text in English; Abstract: Turkish and English

xi, 77 leaves

Link capacity functions are the relationships among the main variables of the vehicular traffic flow at any links. Moreover, developing link capacity function is a task that is related to traffic engineering, yet it is too difficult to find a unique link capacity function belonging to all links in cities. Therefore, this thesis does aim to develop link capacity functions peculiar to the selected divided and undivided links in downtown city İzmir. The main process of developing the link capacity functions depends upon the fastidious site selection, data collection and data analyses techniques. Especially, the main vehicular traffic variables such as flow rate, capacity, speed, travel time data describe the links capacity function. After the data collection process, the data manipulation and their analyses lead to build mathematical model about the link capacity functions. When considering the steps of this thesis, first of all, this thesis reviews the literature and formulates the problem statement and the research objective. Secondly, it conducts the task that consists of the site selection and data collection. In the following parts, this thesis study manipulates and analyzes the obtained data. Then, it performs the linear and non-linear model building by utilizing different functions called V/C ratio & dummy variable, BPR (Bureau of Public Roads) function and Overgaard function for the selected link groups in İzmir. Ultimately, this thesis study compares the model results and manifests the best link capacity function model.

The impact of low-cost airlines on Madeira Islands

Scipedia content — Tue, 26 Jan 2021 15:51:11 +0100

JEL Classifications: L93 - Air Transportation R11 - Regional Economic Activity: Growth, Development, and Changes This study identifies the short term impacts of Low-Cost Airlines (LCAs) on Madeira Islands. By analysing the relevant literature, this study describes the interdependence between tourism and air transport, and the effect that the low-cost airline concept has on both industries. Both generic and industry specific impacts are drawn from the literature, while explaining the advantages and disadvantages of this airline business model. LCAs have experienced tremendous growth in Europe since its birth in the mid 1990’s and have now reached Madeira Islands, a tourism destination still served mainly by charter operations offering tour operator’s package holidays. Research made out of airport and tourism statistics, shows evidence of a significant mismatch between offer and demand in the tourism industry that could possibly be diminished by the entry of LCAs in the market. Findings suggest that, as previously observed for other regions, LCAs do in fact generate significant airport passenger growth, therefore increasing the number of tourists visiting the islands and spending nights at the hotels. However, the average length of stay decreases as more flight frequency induces flexibility and shot-break vacations. While long term impacts are yet to be measured, in order to achieve a balance between tourism supply and demand, as well as higher economic development, all players in the market must join efforts in developing strategies that will promote sustained growth. Este estudo identifica os impactos de curto prazo das companhias aéreas low-cost na Região Autónoma da Madeira. Através da análise da literatura relevante, este estudo descreve a interdependência entre o turismo e o transporte aéreo, bem como o efeito que o conceito de companhia aérea low-cost tem em ambas as indústrias. Impactos genéricos e específicos foram retirados da literatura, explicando as principais vantagens e desvantagens deste modelo de negócio. Tendo crescido significativamente na Europa, desde o seu aparecimento na década de 90, as companhias aéreas low-cost chegaram agora à Região Autónoma da Madeira, um destino turístico ainda maioritariamente servido por operações charter. A pesquisa efectuada com base nas estatísticas dos aeroportos e turismo, evidenciam um desiquilíbrio entre a oferta e a procura no sector do turismo, que pode eventualmente ser atenuado pela entrada de companhias aéreas lowcost no mercado. Os resultados obtidos sugerem que, à semelhança do verificado anteriormente noutras regiões, as companhias aéreas low-cost geram um crescimento significativo do tráfego aéreo de passageiros, consequentemente contribuindo para o aumento do número de turistas que visitam as ilhas e respectivas dormidas. Contudo, devido à maior flexibilidade decorrente da crescente disponibilização de voos que potencia estadias de menor duração, a estada média decresce. Embora os impactos de longo prazo estejam ainda por medir, de modo a obter o equilíbrio entre a oferta e procura no sector do turismo, bem como maior desenvolvimento económico, todos os agentes presentes no mercado deverão conciliar esforços no sentido de desenvolver estratégias que promovam um crescimento sustentado.

Availability assessment of critical computer systems in airspace control by analytical model of queueing theory.

Scipedia content — Tue, 26 Jan 2021 15:48:12 +0100

O transporte aéreo e a indústria de sistemas de defesa foram setores pioneiros na utilização de sistemas computacionais críticos, incrementando os níveis de automação nas atividades de controle do espaço aéreo. Com o crescimento desses setores, verificado pela expansão dos números de vôos, volumes de cargas e usuários, assim como pela ampliação e diversidade das operações militares, os sistemas de controle têm assumido maior complexidade técnica, introduzindo novos recursos de automação ou facilidades adicionais de apoio para funções exercidas manualmente. Essa situação tem ampliado a dependência dos serviços prestados, relativamente à disponibilidade dos sistemas computacionais. Diretrizes de projeto e procedimentos operacionais são estabelecidos para manter os níveis de segurança nos casos de falha, no entanto a disponibilidade torna-se parâmetro crítico, na medida em que algumas falhas podem afetar a eficiência nominal da prestação dos serviços. Nesse cenário, este trabalho propõe um modelo para avaliação da disponibilidade de sistemas de controle do espaço aéreo, a partir de recursos de análises da teoria de filas. Inicialmente é citado um modelo geral para análise de disponibilidade de data centers. Em seguida, é apresentada uma extensão do modelo geral para análise da disponibilidade em sistemas de controle do espaço aéreo. Para isso, considerou-se a intervenção humana existente nessa atividade, cujas decisões de controle são exercidas por operadores qualificados (controladores), tanto nas atividades inerentes ao serviço de controle, quanto nos casos de degradação, nos quais os operadores ou técnicos de manutenção assumem alguma tarefa de reparo, decorrente da eventual indisponibilidade de funções do sistema. Due to the growth in airspace utilization, which can be verified both in terms of the expansions in aerial movements, airports and volumes of transported passengers and cargo, as well as in terms of the expansion of military operations demands and diversity, airspace control activities have been increasing their technical complexity, introducing new features into the existent automation systems or creating additional resources for the automation of some functions previously performed by human operators. This situation has increased the dependence on the availability of the computer systems involved in the services provided by control centers. Project directives and operational procedures are established in order to maintain the safety integrity levels of the systems, in case any failure occurs. However, the availability becomes a critical parameter, once failure events can force an undesirable state of degraded operation, jeopardizing the nominal capacity of the services being performed through any controlled airspace. In this scenario, this work presents an availability model for the computer systems used in airspace control centers, based on analysis from queuing theory. A general model is first presented, referencing a case study that describes the use of queuing models to access the availability of generic data centers. Further considerations are introduced to extend this general model in order to propose its application for the specific computer systems used in airspace control centers, where operational control relies on human activities. In this case, system operation involves intensive use of human-machine interfaces (HMI), for the regular control services provided, and additional technical or operational maintenance activities, occasionally imposed to repair a momentary loss of any function of the system.

Alternatives for sand and crushed stone transportation.

Scipedia content — Tue, 26 Jan 2021 14:18:02 +0100

O presente trabalho versa sobre a possibilidade de redução de custos com a utilização de modais de transportes alternativos ao rodoviário, como o ferroviário e o hidroviário, para a obtenção de areia e brita, agregados para a construção civil de baixo preço, que têm volume de consumo bastante elevado, para sua disponibilização na cidade de São Paulo. As atividades de mineração assim como as demais atividades econômicas na era da globalização têm suas operações bastante semelhantes a níveis de custo, com pouca ou nenhuma possibilidade de redução, sem afetar diretamente a qualidade. O que se busca é identificar alternativas de ganho na competitividade por meio da redução de custos logísticos, única opção para atingir um melhor preço de venda. Para tanto, valeu-se de estudo das características e aplicabilidade das várias formas de transporte, como fator estratégico para a composição de custos adequados à competitividade desejada pelas empresas envolvidas na sua comercialização. Ao mesmo tempo, no emprego dessas alternativas de transporte, encontra-se a possibilidade de redução do congestionamento do tráfego e de melhoria na condição ambiental pela utilização de modais mais limpos. Trata-se de estudo de caso de natureza descritivo-exploratória do tipo quali-quantitativo com coleta de dados por meio de entrevista aberta, de pesquisa documental e bibliográfica. A discussão dos dados, oriundos das fontes primárias e da simulação permitiu chegar ao resultado que viabiliza a utilização do modal ferroviário a curto prazo e a utilização do hidroviário mais a longo prazo pela inexistência de infra-estrutura. O seu emprego resulta, além da redução de custos com frete, na melhoria do tráfego de veículos e na qualidade ambiental. This work aims at focusing the possibility of cost reduction by the utilization of alternative means of transportation in relation to highways, railways and waterways in order to obtain sand and gravel, which are highly consumed, for civil construction at low added value to be available in São Paulo city. The mining activities as well as the other economic activities in the globalization era have very similar operations at cost level, having little or no possibility of reduction without directly affecting quality. What is searched is the identification of gain alternatives in competitiveness by reducing costs in logistics, it being the only option to reach a better sale price, by means of studying characteristics and applicability of various ways of transportation, as a strategic factor to compose adequate costs in relation to the competitiveness desired by the companies involved in their commerce. Likewise in the application of such alternatives of transportation there is a possibility of reducing traffic jams and improving the environmental condition by using cleaner means. It is a case study of descriptive-exploratory nature of the qualitative-quantitative type with collection of data in open interviews, documental and bibliographical research. The discussion of data coming from primary sources and from simulation made possible the result that makes viable the utilization of railway means in the short run and the utilization of waterway in the long run due to lack of infrastructure. Besides cost reduction in freight, its application brings improvement to traffic of vehicles and environmental quality.

Exploiting individual wheel actuators to enhance vehicle dynamics and safety in electric vehicles

Scipedia content — Tue, 26 Jan 2021 14:17:04 +0100

This thesis is focused on individual wheel actuators in road vehicles intended for vehicle motion control. Particular attention is paid to electro-mechanical actuators and how they can contribute to improving vehicle dynamics and safety. The employment of individual wheel actuators at the vehicle's four corner results in a large degree of over-actuation. Over-actuation has a potential of exploiting the vehicle's force constraints at a high level and of controlling the vehicle more freely. One important reason for using over-actuated vehicles is their capability to assist the driver to experience the vehicle as desired. This thesis demonstrates that critical situations close to the limits can be handled more efficiently by over-actuation. To maximise the vehicle performance, all the available actuators are systematically exploited within their force constraints. Therefore, force constraints for the individually controlled wheel are formulated, along with important restrictions that follow as soon as a reduction in the degrees of freedom of the wheel occurs. Particular focus is directed at non-convex force constraints arising from combined tyre slip characteristics. To evaluate the differently actuated vehicles, constrained control allocation is employed to control the vehicle. The allocation problem is formulated as an optimisation problem, which is solved by non-linear programming. To emulate realistic safety critical scenarios, highly over-actuated vehicles are controlled and evaluated by the use of a driver model and a validated complex strongly non-linear vehicle model. it is shown that, owing to the actuator redundancy, over-actuated vehicles possess an inherent capacity to handle actuator faults, with less need for extra hardware or case-specific fault-handling strategies. QC 20100722

Simulation-Based Study to Quantify Data-Communication Benefits in Congested Airport Terminal Area

Scipedia content — Tue, 26 Jan 2021 14:16:16 +0100

The scope of this study was to evaluate the impact of the air traffic controller-to-pilot communication standard known as CPDLC or Data-Communication on the future air traffic operations. The impact was evaluated from the double viewpoint of airport delays and air traffic controllersâ workload. RAMS simulation software is used to perform all the runs and from its output data the values of terminal area delays and controllers workload are obtained. The New York Metroplex terminal area was used as a case study. Because of its complexity, where three major airports (i.e. JFK, Newark, and La Guardia) interact and constraint each other, this area was particularly interesting to be studied and the data analyzed gave a valuable insight on the possible future impact of Data-Communication in congested terminal areas. The results of the study, based on some previous man-in-the-loop simulations performed by the FAA in the nineties, showed that significant potential benefits could be obtained with the complete implementation of such technologies in the workload experienced by air traffic controllers. Moreover some small but not negligible benefits were obtained in the total delays accrued by each airport studied. On the other hand, the simulations of the future demand predicted by the FAA demonstrated that without a significant increment in capacity or limitation on the traffic growth intolerable delays would be recorded across the NAS in the future. For the complexity of the simulation model calibration and for the very time-consuming run time not all the scenarios described in the methodology were tested, demonstrating the weakness of RAMS as a ground simulation model. Master of Science

Pokročilé možnosti technologie MPLS

Scipedia content — Tue, 26 Jan 2021 14:10:24 +0100

Tato práce se zabývá technologií Multiprotocol Label Switching a to zejména moderními metodami, které je možné použít v rámci této technolologie. Jako příklad lze uvést využití podpory kvality služeb při směrování. V práci jsou navrhnuty a simulovány různé topologie a scénáře, které ověřují možnosti využití MPLS v podpoře kvality služeb. This work is considered to evaluate the needs of MPLS implementation in current IP networks with respect to Quality of Service guarantees. It shows many aspects and evaluations of the influence of different traffic classes. The best solutions are evaluated with simulations and can be implemented with respect to Quality of Service guarantees. A

Land cover mapping of the metropolitan railway right of way: Line F in São Paulo.

Scipedia content — Tue, 26 Jan 2021 13:51:17 +0100

O transporte ferroviário de passageiros ganha importância estratégica na melhoria do trânsito e qualidade de vida dos grandes centros urbanos, mas no Brasil enfrenta sérios problemas operacionais, como obsolescência da infra-estrutura e invasão da faixa de domínio, comprometendo sua segurança e operacionalidade. O objetivo central deste trabalho é o mapeamento da cobertura do solo ao longo da faixa de domínio de uma linha de trem metropolitano. A área de estudo concentra-se nas adjacências da Linha F de trem metropolitano de São Paulo, operada pela CPTM Companhia Paulista de Trens Metropolitanos, com 38,8 km de extensão, cruzando as zonas central e leste da capital paulista, estendendo-se até outros municípios da Grande São Paulo. A metodologia adotada compreende o uso de imagem de satélite de alta resolução espacial IKONOS II, e técnica de classificação baseada em regiões. Os classificadores por regiões utilizam, além de informação espectral de cada pixel, a informação espacial que envolve a relação entre os pixels e seus vizinhos. Através da interpretação visual, foram identificadas doze classes de coberturas do solo, cujas feições nortearam os parâmetros da segmentação. A imagem segmentada foi então classificada usando o algoritmo de Bhattacharyya e pós-classificada utilizando regras e critérios definidos para cada classe, de acordo com seus atributos e contextualização. O desempenho da classificação final foi avaliado com base no coeficiente Kappa tendo atingido nível aceitável de correspondência. O mapa de cobertura do solo gerado a partir da classificação, demonstra que o entorno da linha é composto, predominantemente, por materiais impermeáveis como asfalto e concreto mas possui presença significativa de elementos naturais como vegetação e água. Desta forma, comprova-se a aplicabilidade de imagem de satélite de alta resolução e técnicas de processamento de imagem como suportes ao planejamento e gerenciamento do entorno da ferrovia. The rail transport of passengers has strategic importance in the traffic and quality of life improvement in the downtowns, but in Brazil it faces serious operational problems such as obsolete infrastructure and invasion of the right of way, compromising its safety and operability. The principal aim of this paper is the mapping of land cover area of metropolitan railway right of way. The study focuses on the outskirts of the Line F metropolitan train in Sao Paulo, operated by CPTM - Companhia Paulista de Trens Metropolitanos, with 38,8 km long, crossing the central and eastern areas of São Paulo, extending to other cities in the Metropolitan Region of Sao Paulo. The methodology includes the use of the high spatial resolution satellite image - IKONOS II, and regions-based classification. The regions-based classifiers use, besides spectral information of each pixel, the spatial information that involves the relationship between the pixels and its neighbours. Through visual interpretation, were identified twelve classes of land covers, which features guided the segmentation parameters. The segmented image was classified using Bhattacharyya distance and post-classified using rules and criteria established for each class, according to their attributes and contextualization. The performance of the final classification was evaluated based on Kappa coefficient, resulting acceptable level of correspondence. The mapping of land cover generated from the classification, shows that the outskirts of the metropolitan railway`s right way is predominantly composed by impermeable materials - such as asphalt and concrete - but has significant presence of natural elements - such as vegetation and water. Thus, is evident the applicability of high spatial resolution satellite image added to classification methods for remotely sensed data for planning and management of the railway right of way.

Relationship between air transport and tourism : a case study of Nepal

Scipedia content — Tue, 26 Jan 2021 13:37:09 +0100

Runway Operations Scheduling using Airline Preferences

Scipedia content — Tue, 26 Jan 2021 13:32:41 +0100

Alternative Land Use Patterns to Minimize Congestion (Volume 2: Evaluating the Feasibility of New Urbanism in an Existing Neighborhood)

Scipedia content — Mon, 25 Jan 2021 20:15:08 +0100

Urban sprawl creates serious traffic congestion. Alternative land use patterns may be the best solution. New Urbanists claim that, by placing frequently-visited sites within walking distance of homes and creating a pleasant walking environment, people are more willing to choose non-motorized transportation mode to do such activities. Part I of this study investigated the ability of travel demand models to estimate the impacts of alternative land use patterns. Part II conducted an economic viability analysis for a mixed land use neighborhood and collected land use preferences at meetings of neighborhood associations. The objective in Part III was to evaluate the feasibility of implementing mixed land use neighborhood, based upon public acceptance, actual impacts on travel behavior and observed trip making patterns. Surveys were conducted and analyzed for this report. A brief summary of the principal findings of this study will be posted on a website – either JTRP or INDOT. The findings will include brief numerical examples of the analyses that led to the report’s conclusions. Figures and photos will be used to illustrate the alternatives and performance measures that support the project’s findings.

Abstractions of Stochastic Hybrid Systems

Scipedia content — Mon, 25 Jan 2021 19:49:25 +0100

Many control systems have large, infinite state space that can not be easily abstracted. One method to analyse and verify these systems is reachability analysis. It is frequently used for air traffic control and power plants. Because of lack of complete information about the environment or unpredicted changes, the stochastic approach is a viable alternative. In this paper, different ways of introducing rechability under uncertainty are presented. A new concept of stochastic bisimulation is introduced and its connection with the reachability analysis is established. The work is mainly motivated by safety critical situations in air traffic control (like collision detection and avoidance) and formal tools are based on stochastic analysis.

The Challenge of Rapidly Improving Transport Infrastructure in Poland

Scipedia content — Mon, 25 Jan 2021 19:33:14 +0100

Following many years of underinvestment, renovating and building new transport infrastructure is an important policy priority that would increase labour mobility and improve Poland’s competitiveness. This goal is all the more feasible given that the country is going to benefit from substantial EU structural and cohesion funds over the programming period 2007-13. On top of the limited timeframe for the absorption of EU funds, the European soccer championship that Poland is going to co-host with Ukraine in 2012 imposes an additional time constraint on many investment projects. The country is heavily reliant on road transport but is lacking an efficient high-speed road network. It needs important renovation investments both in the rolling stock and infrastructure network of the railway sector. It also faces the challenges of revitalising maritime transport as well as extending and upgrading airport facilities to cope with the fastest growing air market in Europe. However, many obstacles remain and hinder the implementation of investment plans and thus need to be resolved rapidly. From the macroeconomic perspective, these are related to rising prices of scarce labour and intermediate inputs, while from the microeconomic standpoint the main difficulties lie in the area of the regulatory framework underlying the provision of physical infrastructure. Le defi d'une amelioration rapide des infrastructures de transport en Pologne Apres des annees de sous-investissement, la renovation des infrastructures de transport existantes et la construction d’infrastructures nouvelles representent une importante priorite d’action en vue d’accroitre la mobilite de la main-d’oeuvre et d’ameliorer la competitivite de la Pologne. Cet objectif est d’autant plus realisable que le pays va beneficier d’un volume substantiel de fonds structurels et de fonds de cohesion de l’UE au cours de la periode de programmation 2007-13. Outre que l’utilisation des fonds europeens est soumise a un calendrier restreint, le championnat d’Europe de football que la Pologne organisera conjointement avec l’Ukraine en 2012 impose une contrainte temporaire supplementaire sur de nombreux projets d’investissement. Lourdement tributaire du transport routier, la Pologne est depourvue d’un reseau autoroutier efficace. Dans le secteur ferroviaire, le materiel roulant comme le reseau d’infrastructure necessitent d’importants investissements de renovation. De surcroit, il faut revitaliser les transports maritimes mais aussi agrandir et moderniser les installations aeroportuaires afin de faire face a une croissance du marche des transports aeriens sans equivalent en Europe. Cependant, de nombreux obstacles subsistent et entravent la mise en oeuvre des plans d’investissement ; il faut donc y porter remede sans tarder. Sur un plan macroeconomique, ces freins resident dans la hausse des prix de ressources limitees en main-d’oeuvre et en intrants intermediaires, tandis que d’un point de vue microeconomique, les principales difficultes tiennent au cadre reglementaire qui sous-tend la fourniture d’infrastructures physiques.

Remaining Sites Verification Package for the 100-F-26:9, 1607-F2 Sanitary Sewer Pipelines, Waste Site Reclassification Form 2008-029

Scipedia content — Mon, 25 Jan 2021 19:21:28 +0100

The 100-F-26:9 underground pipeline subsite consists of the sanitary sewers servicing the 105-F, 108-F, 184-F, 185-F, and 190-F buildings, and the 1700-F administration and service buildings (1704-F, 1707-F, 1707-FA, 1713-F, 1717-F, 1719-F, and 1722-F). In accordance with this evaluation, the confirmatory and verification sampling results support a reclassification of this site to Interim Closed Out. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Analysis of Cost-Effective Off-Board Hydrogen Storage and Refueling Stations

Scipedia content — Mon, 25 Jan 2021 19:14:50 +0100

This report highlights design and component selection considerations for compressed gas hydrogen fueling stations operating at 5000 psig or 350 bar. The primary focus is on options for compression and storage – in terms of practical equipment options as well as various system configurations and how they influence delivery performance and station economics.

National Account Energy Alliance Final Report for the Basin Electric Project at Northern Border Pipeline Company's Compressor Station #7, North Dakota

Scipedia content — Mon, 25 Jan 2021 19:08:20 +0100

field research test and verification project was conducted at the recovered energy generation plant at Northern Border Pipeline Company Compressor Station #7 (CS#7) near St. Anthony. Recovered energy generation plant equipment was supplied and installed by ORMAT Technologies, Inc. Basin Electric is purchasing the electricity under a purchase power agreement with an ORMAT subsidiary, which owns and operates the plant.

Measures of International Transport Cost for OECD Countries

Scipedia content — Mon, 25 Jan 2021 18:51:01 +0100

This paper presents new estimates of country-specific international transport costs for 21 OECD countries over the period 1973-2005. The methodology is based on direct measures of air, maritime, and road transport costs rather than on cif/fob ratios or other balance of payments data employed in previous studies. Transport costs are calculated as costs per kilogramme for each mode of transport at a bilateral level and then aggregated. Australia and New Zealand are found to have the highest transport costs among the OECD countries considered, followed by Japan. The time trends are sensitive to the choice of deflator, but the results do not show an overall downward trend in transport costs for OECD countries, contrary to conventional wisdom, but consistent with Hummels’ (2007) recent study of global transport costs. Les mesures internationales des couts de transport pour les pays OCDE Ce document presente des nouvelles estimations de couts de transport internationaux par pays, pour 21 membres de l’OCDE pendant la periode 1973-2005. La methode repose sur des mesures directes des couts de transport par voies maritime, aerienne et routiere, plutot que sur des ratios cif/fob ou d’autres donnees issues de la balance des paiements employes dans des etudes precedentes. Les resultats indiquent que l’Australie et la Nouvelle Zelande ont les couts de transport les plus eleves parmi les pays de l’OCDE consideres, suivi par le Japon. Les tendances dans le temps sont sensibles au choix du deflateur, mais il n’apparait pas de tendance globale a la baisse des couts de transports pour les pays de l’OCDE, contrairement aux idees recues, mais en accord avec l’etude recente de Hummels (2007) sur les couts de transport au niveau mondial.

Physiological and behavioural aspects of housing stress in cattle

Scipedia content — Mon, 25 Jan 2021 18:47:11 +0100

End of project report The effect of various space allowances on pituitary, adrenal, immune responses and performance was investigated in 72 Holstein x Friesian bulls. Bulls (403 ± 3.5 kg) were blocked by weight and randomly assigned into two groups (familiar, F and unfamiliar, UF) x three (1.2, 2.7 and 4.2 m2 per bull; n = 24 bulls per space allowance) treatments and housed for 83 days in 18 pens (n = 4 per pen). Blood samples were collected on day –1, 0, 3, 14, 36 and 77 with respect to mixing and housing on day 0. The bulls were administered with adrenocorticotrophic hormone (ACTH) on day 3 and corticotrophin-releasing hormone (CRH) on days 14, 36 and 77. The basal cortisol concentrations were not affected (P"0.05) by mixing of familiar and unfamiliar bulls. On day 3, basal cortisol was greater (P"0.05) in the bulls housed at 1.2 than those at 2.7 and 4.2 m2 space allowances while no effect was observed in ACTH-induced plasma cortisol concentration among treatments. Following CRH administration there was no effect (P"0.05) of treatment and treatment x time on ACTH. On day 14, interferon-? production was lower (P"0.05) in the bulls housed at 4.2 vs 2.7 m2 and was intermediate but not (P"0.05) different for those housed at 1.2 m2. Bulls housed at either space allowances had (P"0.05) neutrophilia, lymphopenia, eosinopenia and decreased haemoglobin on day 3 compared with day 0. The liveweight gain from days 0 to 83 was lower (P" 0.05) in bulls housed at 1.2 compared with those at 2.7 and 4.2 m2. Housing bulls at 1.2 m2 space allowance had a detrimental effect on their growth and was associated with an acute rise in plasma cortisol concentration (on day 3) compared with space allowances of 2.7 and 4.2 m2/bull. European Union Structural Funds (EAGGF)

Remaining Sites Verification Package for the 100-F-26:14, 116-F-5 Influent Pipelines, Waste Site Reclassification Form 2007-029

Scipedia content — Mon, 25 Jan 2021 18:34:35 +0100

The 100-F-26:14 waste site includes underground pipelines associated with the 116-F-5 Ball Washer Crib and remnants of process pipelines on the west side of the 105-F Building. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Vehicle routing under time-dependent travel times: The impact of congestion avoidance

Scipedia content — Mon, 25 Jan 2021 18:09:31 +0100

Daily traffic congestions form major problems for businesses such as logistical service providers and distribution firms. They cause late arrivals at customers and additional hiring costs for the truck drivers. The additional costs of traffic congestions can be reduced by taking into account and avoid well-predictable traffic congestions within off-line vehicle route plans. In the literature, various strategies are proposed to avoid traffic congestions, such as selecting alternative routes, changing the customer visit sequences, and changing the vehicle-customer assignments. We investigate the impact of these and other congestion avoidance strategies in off-line vehicle route plans on the performance of these plans in reality. For this purpose, we develop a set of VRP instances on real road networks, and a speed model that inhabits the main characteristics of peak hour congestion. The instances are solved for different levels of congestion avoidance using a modified Dijkstra algorithm and a restricted dynamic programming heuristic. Computational experiments show that 99% of late arrivals at customers can be eliminated if traffic congestions are accounted for off-line. On top of that, almost 70% of the extra duty times caused by the traffic congestions can be eliminated by clever avoidance strategies.

Optical sensor to measure the projectile velocity

Scipedia content — Mon, 25 Jan 2021 18:00:38 +0100

Displays & Photonics Applications Group (GDAF), belonging to Electronics Technology Department of University Carlos III of Madrid (Spain), has designed and implemented a simple, cost-effective, and robust optoelectronic system to measure online the average velocity of a projectile. This system is able to measure velocities ranged between 100m/s and 1200m/s). Potential applications are focused on experimental impact tests on aircraft and spacecraft structures. We are seeking potential collaborations with international/national research centres and enterprises to extent the range of potential applications.

How do Incumbents Respond to the Threat of Entry? Evidence from the Major Airlines

Scipedia content — Mon, 25 Jan 2021 17:57:14 +0100

This paper examines how incumbents respond to the threat of entry of competitors, as distinguished from their response to competitors’ actual entry. It uses a case study from the passenger airline industry—specifically, the evolution of Southwest Airlines’ route network—to identify particular routes where the probability of future entry rises abruptly. When Southwest begins operating in airports on both sides of a route but not the route itself, this dramatically raises the chance they will start flying that route in the near future. We examine the pricing of the incumbents on threatened routes in the period surrounding such events. We find that incumbents cut fares significantly when threatened by Southwest’s entry into their routes. This is true even after controlling in several ways for airport-specific operating costs. The response of incumbents seems to be limited only to the threatened route itself, and not to routes out of nearby competitor airports where Southwest does not operate (e.g., fares drop on routes from Chicago Midway but not Chicago O’Hare). The largest responses appear to be restricted to routes that were concentrated beforehand. Incumbents do experience short-run increases in their passenger loads concurrent with these fare cuts. This is consistent with theories implying incumbents will try to generate some longer-term loyalty among current customers before the entry of a new competitor. We examine evidence relating this demand-building motive to frequent flyer programs and find suggestive evidence in favor of this notion. There is only weak evidence that incumbents increase capacity on the routes.

The Costs and Effectiveness of Police to Reduce Vehicle Emissions

Scipedia content — Mon, 25 Jan 2021 17:47:08 +0100

Transport sector policies already contribute to moderating greenhouse gas emissions from road vehicles and are increasingly designed to contribute to overall societal targets to mitigate climate change. The Round Table investigated the effectiveness and costs of various mitigation options. The question of how to decide on the distribution of abatement efforts across sectors of the economy was also discussed. Within the broad topic of addressing greenhouse gas emissions from transport, the Round Table focused on emissions of CO2 from road transport and in particular from light-duty passenger vehicles. Policies that reduce fuel consumption below non-intervention levels are in place in most countries, many adopted for reasons other than reducing CO2 emissions. In the US, both fuel taxes and fuel economy regulations have been in force for some decades. European governments have adopted high fuel taxes but are now considering introducing fuel economy regulations. A first core question for the Round Table was whether such a combination of instruments is justified. A second question was whether current policies, and the level of taxes and standards, are in line with societal climate change mitigation goals and, more generally, how such goals ought to be defined.

Določanje dejanske propustne sposobnosti krožnega križišča z uporabo mikrosimulacije in diskretnih funkcij

Scipedia content — Mon, 25 Jan 2021 17:43:04 +0100

The paper demonstrates the influence of the multi-channel pedestrian flow on the actual capacity of a one-lane roundabout, using micro-simulation and discrete functions. The proposed model is based on the theory of the expected time gap between the units of pedestrian traffic flow, which have the priority when crossing the arm of the roundabout. The proposed model represents an upgrade of the previous research in the field of modelling traffic flows in the one-lane roundabout.Apart from the multi-channel pedestrian flow the disturbances caused by the circular traffic flow of motorised vehicles at the roundabout are also considered. In this way the model can better illustrate the real conditions in traffic. A simulation analysis has been performed on the roundabout arm at Koroška Street in Maribor. The results of the analysis have indicated a relatively high reserve of the actual throughput capacity for the main motorized traffic flow in the analysed roundabout arm. The presented model represents a practicable and adaptable tool for planning the roundabout capacity in practice and for the sensitivity analysis of individual variables on the throughput capacity of the roundabout. Prispevek prikazuje vpliv večkanalnega toka pešcev na dejansko propustno sposobnost eno-pasovnega krožnega križišča z uporabo mikro-simulacij in diskretnih funkcij. Predlagani model temelji na teoriji pričakovane časovne praznine med enotami prometnega toka pešcev, ki imajo pri prečkanju kraka krožnega križišča prednost pred motornimi vozili. Predlagani model predstavlja nadgradnjo predhodnih raziskav na področju modeliranja prometnih tokov v enopasovem krožnem križišču. Poleg večkanalnega toka pešcev so hkrati upoštevane tudi motnje zaradi krožečega toka motornih vozil v krožišč. S tem je doseženo, da model se bolje ponazarja realno dogajanje v prometu. Simulacijska analiza je bila izvedena na krožnem križišču, ki se nahaja na Koroški ulici v Mariboru. Rezultati analize so pokazali sorazmerno visoko propustno sposobnost glavnega prometnega toka motornih vozil v analiziranem kraku krožišča. Predstavljeni model predstavlja uporabno in prilagodljivo orodje za načrtovanje kapacitete krožišč v praksi in analiza vpliva posameznih spremenljivk na propustno sposobnost krožišča.

Outsourcing logistics at petrol stations in Slovenia

Scipedia content — Mon, 25 Jan 2021 17:37:24 +0100

The environmental disburdening by means of outsourcing logistics (sorting, bundling, transport) is today significantly more present, since this has been regulated by the law provisions on environmental protection and the economic reasons. Outsourcing logistics in this field with its activities such as: improvement in assembling separate fraction, introduction of new, i. e. additional boxes, usage of specific vehicles for collection and dispatch, reestablishment of information systems and organization of a centre for disburdening of the environment(sorting, bundling and waste disposal) is contributing largely to a better accomplishment of the mission of logistics rationalization and adaptation to new law claims on environmental protection. Razbremenjevanje okolja s pomočjo razbremenilne logistike (sortiranje, zbiranje, transport) je v podjetjih današnjega časa vedno bolj aktualno, saj nas k temu zavezujejo zakonski predpisi o varstvu okolja in ekonomski razlogi. Razbremenilna logistika na tern področju s svojimi aktivnostmi kot so: racionaliziranje zbiranja ločenih frakcij, uvedba novih oz. dodatnih zabojnikov, uporaba specifičnih vozil za zbiranje in odvoz, vzpostavitev celovitega informacijskega sistema in ureditev centra za razbremenjevanje (sortiranje, zbiranje in ravnanje z odpadki) odločilno vpliva k uresničevanju nalog v zvezi z racionalizacijo logistike, prilagajanjem zakonskim zahtevam glede varstva okolja.

Remaining Sites Verification Package for the 100-F-26:13, 108-F Drain Pipelines, Waste Site Reclassification Form 2005-011

Scipedia content — Mon, 25 Jan 2021 17:35:41 +0100

The 100-F-26:13 waste site is the network of process sewer pipelines that received effluent from the 108-F Biological Laboratory and discharged it to the 188-F Ash Disposal Area (126-F-1 waste site). The pipelines included one 0.15-m (6-in.)-, two 0.2-m (8-in.)-, and one 0.31-m (12-in.)-diameter vitrified clay pipe segments encased in concrete. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.

The Economic Effects of High Speed Rail Investment

Scipedia content — Mon, 25 Jan 2021 17:22:22 +0100

The allocation of traffic between different transport modes follows transport user decisions which depend on the generalized cost of travel in the available alternatives. High Speed Rail (HSR) investment is a government decision with significant effects on the generalized cost of rail transport; and therefore on the modal split in corridors where private operators compete for traffic and charge prices close to total producer costs (infrastructure included). The rationale for HSR investment is not different to any other public investment decision. Public funds should be allocated to this mode of transport if its net expected social benefit is higher than in the next best alternative. The exam of data on costs and demand shows that the case for investing in HSR is strongly dependent on the existing volume of traffic where the new lines are built, the expected time savings and generated traffic and the average willingness to pay of potential users, the release of capacity in congested roads, airports or conventional rail lines and the net reduction of external effects. This paper discusses, within a cost-benefit analysis framework, under which conditions the expected benefits from deviated traffic (plus generated traffic), and other alleged external effects and indirect benefits justify the investment in HSR projects. It pays special attention to intermodal effects and pricing.

Capital-Intensive Projects Induce More Effort Than Labor-Intensive Projects

Scipedia content — Mon, 25 Jan 2021 17:09:57 +0100

Central governments often subsidize capital spending by local governments, instead of subsidizing operating expenses or labor-intensive projects. This paper offers one explanation, focusing on the incentive effects for local officials. a local official can more easily shift the cost of optimizing a project to his successor on a labor-intensive project than on a capital-intensive project. ispartof: CES - Discussion paper series (DPS) 08.31 pages:1-12 status: published

On the Long-Term Average Cost of CO2 Transport and Storage

Scipedia content — Mon, 25 Jan 2021 16:58:16 +0100

Paper describes general trends in the cost of CO2 transport and storage (including measurement, monitoring, and verification) and how these can be used to justify a proxy cost to cover a large number of potential CCS commercial deployment scenarios.

Transport Outlook 2008

Scipedia content — Mon, 25 Jan 2021 16:51:44 +0100

This short outlook is designed to test the potential for key policy instruments for mitigating emissions from road transport, and particularly from light duty vehicles, the largest source of CO2 emissions from transport (see Figure 1 and Table 1). It also examines uncertainties in the baseline scenario for the development of CO2 emissions from the sector. In contrast to the OECD’s Economic Outlook and the IEA’s World Energy Outlook, the Transport Outlook is produced making use of external modeling tools. The work uses the most transparent and robust model developed to date for the sector, the MoMo modeli constructed and maintained by the International Energy Agency and initially developed for the World Business Council for Sustainable Development. We are grateful to the MoMo-team for their willingness to share this product. The present document is only a first step towards the development of a full-fledged Transport Outlook. It is limited in scope, with its focus on road transport and on emissions of CO2. Despite the limitations, this mini-Outlook provides elements of a useful framework for discussions on the policy challenges presented by the risk of costly consequences from anthropogenic emissions of greenhouse gases. As will become clear, permanent reductions of CO2-emissions from transport are difficult to achieve because of strong underlying global growth in transport demand. At the same time, our scenarios suggest that emissions could be stabilized even with strong growth of demand, given immediate and continued efforts to reduce the sector’s carbon intensity. If stabilization is the goal, then finding cost-effective ways of achieving it becomes the critical issue.

Alternative Land Use Patterns to Minimize Congestion (Volume 1: Comparative Analysis of Mixed Land Use and Separated Land Use Neighborhoods)

Scipedia content — Mon, 25 Jan 2021 16:50:26 +0100

The "Biogasification" of Linköping : A Large Technical Systems Perspective

Scipedia content — Mon, 25 Jan 2021 16:48:42 +0100

Biogas production is synonymous with Linköping, as an increasing number of internationalvisitors are coming to the region to learn of the biogas system in place. Moreover, Linköpingis a world leader in the production, distribution and research on biogas. Since the 1990s,Linköping, Sweden has been developing a biogas system which is benchmarked worldwide.This system has grown rapidly, and has the potential to expand even further in Sweden andabroad. Many of the leading biogas development industrial actors originate and call Linköpingtheir home. Technologies from this region have thus begun to spread worldwide, as many ofthe benchmarking practices have concluded that the system could provide parallel benefits tocommunities abroad.The biogas system thus provides many examples of a budding large technical system.However, just as other large technical systems, there are obstacles to overcome and the biogassystem, which is relatively recent, has a long way to go before it is able to dominate themarket. Moreover, large technical systems as such owe a great deal to both the technical aswell as the social systems enabling their success. Nonetheless, the biogas system is thusanalyzed an up-and-coming large technical system with force to prevail and expand nationallyand globally. Perspectives on Energy System

Impacts of airports on airline competition: Focus on airport performance and airport-airline vertical relations

Scipedia content — Mon, 25 Jan 2021 16:47:28 +0100

This paper examines revenue structure, regulation, and market power of airports, and how they affect airport's services to airlines and influence the form of vertical relationship between airport and airlines, and thus, eventually on competition in airline markets. In addition, we also examine the competitive consequences of common ownership, coordination or alliance among multiple airports in a region. The key findings are: Concession revenues are of increasing importance to airports. The positive externality of air traffic on the demand for non-aeronautical services, along with competition among both airlines and airports, induces a vertical cooperation between airports and the dominant carrier at the airport. Airports have substantial market power due to the low price elasticity of their aeronautical services. However, such airports' market power is moderated by competition in both the airline and airport markets. There are benefits for both airports and airlines from entering into long term relationships. Airports can obtain financial support and secure business volume, which are important for daily operation as well as for long term expansion. Airlines can secure key airport facilities on favorable terms, essential for making long term commitments/investment at an airport. This along with the positive externality of the demand for airport's aeronautical services on commercial services provides incentives for the airport and the dominant carrier to strike exclusive deals, harming competition in the downstream airline market if unchecked. Such airport dominance allows an airline to obtain a substantial hub premium. On the other hand, cooperation between a hub airport and the dominant carrier may enhance the competition between airline networks formed by different airport-dominant carrier combinations. In other words, airport-airline coordination or alliance is a doubleedged sword for downstream airline competition, there is a need for careful further examination on the issue in order to design an effective regulatory oversight. The issue of cooperation or alliance between two or more hub airports in a region needs more careful analysis because, while cooperation and coordination may improve customer service and efficiency, it is also likely to reduce competition not only between airports in the region but also between carriers in the downstream airline market.

Remaining Sites Verification Package for the 100-F-44:2, Discovery Pipeline Near 108-F Building, Waste Site Reclassification Form 2007-006

Scipedia content — Mon, 25 Jan 2021 16:43:55 +0100

The 100-F-44:2 waste site is a steel pipeline that was discovered in a junction box during confirmatory sampling of the 100-F-26:4 pipeline from December 2004 through January 2005. The 100-F-44:2 pipeline feeds into the 100-F-26:4 subsite vitrified clay pipe (VCP) process sewer pipeline from the 108-F Biology Laboratory at the junction box. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Remaining Sites Verification Package for the 100-F-26:12, 1.8-m (72-in.) Main Process Sewer Pipeline, Waste Site Reclassification Form 2007-034

Scipedia content — Mon, 25 Jan 2021 16:38:59 +0100

The 100-F-26:12 waste site was an approximately 308-m-long, 1.8-m-diameter east-west-trending reinforced concrete pipe that joined the North Process Sewer Pipelines (100-F-26:1) and the South Process Pipelines (100-F-26:4) with the 1.8-m reactor cooling water effluent pipeline (100-F-19). In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Liquidation Values and the Credibility of Financial Contract Renegotiation: Evidence from U.S. Airlines*

Scipedia content — Mon, 25 Jan 2021 16:29:07 +0100

How do liquidation values affect financial contract renegotiation? While the 'incomplete contracting' theory of financial contracting predicts that liquidation values determine the allocation of bargaining power between creditors and debtors, there is little empirical evidence on financial contract renegotiations and the role asset values play in such bargaining. This paper attempts to fill this gap. We develop an incomplete-contracting model of financial contract renegotiation and estimate it using data on the airline industry in the United States. We find that airlines successfully renegotiate their lease obligations downwards when their financial position is sufficiently poor and when the liquidation value of their fleet is low. Our results show that strategic renegotiation is common in the airline industry. Moreover, the results emphasize the importance of the incomplete contracting perspective to real world financial contract renegotiation.

Worse than a Congestion Charge: Paris Traffic Restraint Policy

Scipedia content — Mon, 25 Jan 2021 12:45:18 +0100

This objective of this chapter was to analyze the effects of the traffic restraint policy introduced in 2001 in and by the Paris municipality, and to sketch a comparison with the policy introduced in London at about the same time â with the proviso that the geographic, economic, demographic, institutional, historic and political contexts are very different. The results do not speak highly in favor of the French policy. In both cases, the stated objectives of reducing traffic have been achieved. But success in itself is not enough. One must also see how and to what cost it has been obtained. In London, it has been achieved by means of a toll, and accompanied by an increase in motor vehicle speed, generating a time gain for car users, and also for bus users, and a small environmental gain. In Paris, the main policy instrument has been the reduction of road space for motor vehicles, which led to a decrease in motor vehicle speed, but failed to increase bus speed and patronage. The policy generated a considerable time loss for car users and for goods delivery vehicles, and even environmental losses, without gains for public transport users. The only benefit seems to have been a small one for bicycle users: 0.4 per cent of all losses. The downside for the London policy is the implementation cost, which is high, but which can be expected to decline over time.

Triggering Adaptive Automation in Naval Command and Control

Scipedia content — Mon, 25 Jan 2021 12:24:31 +0100

In many control domains (plant control, air traffic control, military command and control) humans are assisted by computer systems during their assessment of the situation and their subsequent decision making. As computer power increases and novel algorithms are being developed, machines move slowly towards capabilities similar to humans, leading in turn to an increased level of control being delegated to them. This technological push has led to innovative but at the same time complex systems enabling humans to work more efficiently and/or effectively. However, in these complex and information-rich environments, task demands can still exceed the cognitive resources of humans, leading to a state of overload due to fluctuations in tasks and the environment. Such a state is characterized by excessive demands on human cognitive capabilities resulting in lowered efficiency, effectiveness, and/or satisfaction. More specifically, we focus on the human-machine adaptive process that attempts to cope with varying task and environmental demands. In the research field of adaptive control an adaptive controller is a controller with adjustable parameters and a mechanism for adjusting the parameters (Astrom & Wittenmark, 1994, p. 1) as the parameters of the system being controlled are slowly time-varying or uncertain. The classic example concerns an airplane where the mass decreases slowly during flight as fuel is being consumed. More specifically, the controller being adjusted is the process that regulates the fuel intake resulting in thrust as output. The parameters of this process are adjusted as the airplane mass decreases resulting in less fuel being injected to yield the same speed. In a similar fashion a human-machine ensemble can be considered an adaptive controller. In this case, human cognition is a slowly time-varying parameter, the adjustable parameters are the task sets that can be varied between human and machine, and the control mechanism is an algorithm that âhas insightâ in the workload of the human operator (i.e., an algoritm that monitors human workload). Human performance is reasonably optimal when the human has a workload that falls within certain margins; severe performance reductions result from a workload that is either too high or (maybe surprisingly) too low. Consider a situation where the human-machine ensemble works in cooperation in order to control a process or situation. Both the human and the machine cycle through an information processing loop, collecting data, interpreting the situation, deciding on actions to achieve one or more stated goals and acting on the decisions (see for example Coram, 2002;

Control Analysis and Feedback Techniques for Multi Agent Robots

Scipedia content — Mon, 25 Jan 2021 11:52:44 +0100

In this paper, a simulation framework based on the kinematic model for the multi agent robots using the leader-follower formation was presented. The design of feedback controllers for leader-follower formation using feedback linearization techniques was also presented. The follower robots derived their inputs based on the control inputs sent by the leader robot. The leader robot transmitted its control inputs to the follower using the Bluetooth piconet profile. The posture stabilization controllers using smooth time-varying, polar coordinates and dynamic feedback controller were simulated for the leader robot. For trajectory tracking, the reference trajectory was generated using the feedforward command controller. The multi agent nonholonomic robotic system was modeled using MATLAB/Simulink and the feedback strategies were simulated for a given set of reference trajectories. Based on the simulation results for the various trajectories, the following conclusions are made: ? For the leader robot, the full state linearized controller via dynamic feedback minimizes the mean of error more rapidly than the other feedback strategies. ? The full state linearized dynamic feedback controller for the leader robot achieves posture stabilization. ? The feedback strategies designed using cascaded systems theory and using linearization of corresponding error model fail to track the trajectory if the leader robot's starting point and the trajectory starting point is not the same (circular shaped trajectory).

User Requirements for HEO SATCOM for ATM in High Latitudes

Scipedia content — Mon, 25 Jan 2021 11:48:56 +0100

It is currently a significant ongoing effort worldwide to develop the future Air Traffic Management (ATM) system. As part of this work, a satellite communication system may ease the congestion problem for ATM services in high density airspace, and in addition provide coverage in oceanic, remote and polar (ORP) areas. For coverage over polar areas, satellites in highly elliptical orbits (HEO) are particularly suitable. In this paper, an overview of user categories is given and the channel characteristics of an aeronautical satellite channel are considered. Both Molniya and Tundra orbits are included. Curves show how parameters like elevation angle, free space path loss and Doppler shift vary as function of satellite movements. In addition, atmospheric effects due to signal propagation through the ionosphere and the troposphere is considered, and finally the effect of multipath propagation due to signal reflections by the aircraft surface and ground. User Requirements for HEO SATCOM for ATM in High Latitude

Evolutionary Computation Applied to Urban Traffic Optimization

Scipedia content — Mon, 25 Jan 2021 11:23:43 +0100

At the present time, many sings seem to indicate that we live a global energy and environmental crisis. The scientific community argues that the global warming process is, at least in some degree, a consequence of modern societies unsustainable development. A key area in that situation is the citizens mobility. World economies seem to require fast and efficient transportation infrastructures for a significant fraction of the population. The non-stopping overload process that traffic networks are suffering calls for new solutions. In the vast majority of cases it is not viable to extend that infrastructures due to costs, lack of available space, and environmental impacts. Thus, traffic departments all around the world are very interested in optimizing the existing infrastructures to obtain the very best service they can provide. In the last decade many initiatives have been developed to give the traffic network new management facilities for its better exploitation. They are grouped in the so called Intelligent Transportation Systems. Examples of these approaches are the Advanced Traveler Information Systems (ATIS) and Advanced Traffic Management Systems (ATMS). Most of them provide drivers or traffic engineers the current traffic real/simulated situation or traffic forecasts. They may even suggest actions to improve the traffic flow. To do so, researchers have done a lot of work improving traffic simulations, specially through the development of accurate microscopic simulators. In the last decades the application of that family of simulators was restricted to small test cases due to its high computing requirements. Currently, the availability of cheap faster computers has changed this situation. Some famous microsimulators are MITSIM(Yang, Q., 1997), INTEGRATION (Rakha, H., et al., 1998), AIMSUN2 (Barcelo, J., et al., 1996), TRANSIMS (Nagel, K. & Barrett, C., 1997), etc. They will be briefly explained in the following section. Although traffic research is mainly targeted at obtaining accurate simulations there are few groups focused at the optimization or improvement of traffic in an automatic manner â not dependent on traffic engineers experience and âartâ. O pe n A cc es s D at ab as e w w w .ite ch on lin e. co m

Port regions and globalization

Scipedia content — Mon, 25 Jan 2021 11:15:45 +0100

http://www.ashgate.com/default.aspx?page=637&calcTitle=1&title_id=9422&edition_id=12022; The interaction between port activities and regional development has caught the attention of various scholars and decision-makers worldwide. However, without a clear definition of the port region, confusion remains between a group of neighboring ports (e.g. faÃ§ade, range) or an inland service area of a given port (e.g. hinterland). Considering the socio-economic characteristics of regional units around ports is proposed as a possible solution for international comparison. Main results show that in developed countries, specialization in the industrial sector has a negative impact on port performance, while unemployment, GDP, and service concentrations have a positive influence on traffic. This confirms the effects of globalization on port region

A snake-like robot for internal inspection of complex pipe structures (PIKo)

Scipedia content — Mon, 25 Jan 2021 11:10:58 +0100

This paper presents a mechanism for navigating complex pipe structures, both horizontally and vertically. The mechanism consists of a series of identical modules interconnected by two degree of freedom active joints. A set of active wheels on each module provides propulsion. Horizontal motion is achieved through a train-like scheme, while vertical motion is achieved through spanning the pipe alternatingly with the modules. The design and the capability of horizontal and vertical motion is validated through experiments. Â© 2009 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Enhanced transport protocols

Scipedia content — Mon, 25 Jan 2021 10:45:00 +0100

The book presents mechanisms, protocols, and system architectures to achieve end-to-end Quality-of-Service (QoS) over heterogeneous wired/wireless networks in the Internet. Particular focus is on measurement techniques, traffic engineering mechanisms and protocols, signalling protocols as well as transport protocol extensions to support fairness and QoS. It shows how those mechanisms and protocols can be combined into a comprehensive end-to-end QoS architecture to support QoS in the Internet over heterogeneous wired/wireless access networks. Finally, techniques for evaluation of QoS mechanisms such as simulation and emulation are presented. The book is aimed at graduate and post-graduate students in Computer Science or Electrical Engineering with focus in data communications and networking as well as for professionals working in this area.

Monitoring und Evaluation von verkehrlichen Maßnahmen: das Münchner Neubürgerpaket und das Neubürgerpaket für die Region München

Scipedia content — Thu, 21 Jan 2021 15:45:38 +0100

Der Beitrag widmet sich der Wirkungsermittlung und -bewertung von verkehrlichen MaÃnahmen, die das MobilitÃ¤tsverhalten der Verkehrsteilnehmer und damit den Modal Split in Richtung des Umweltverbundes mittels Information und Kommunikation beeinflussen sollen. Im Zentrum der Betrachtungen steht der MaÃnahmenbereich âMobilitÃ¤tspakete fÃ¼r NeubÃ¼rgerâ, dargestellt an den Projekten âMÃ¼nchner NeubÃ¼rgerpaketâ und âNeubÃ¼rgerpaket fÃ¼r die Region MÃ¼nchenâ. Deutlich wird, dass fÃ¼r die dargestellten Projekte eine klare Positionierung und Darstellung eines differenzierten Ziel- und Indikatorensystems sowie zu Methoden des Monitorings und der Evaluation fehlen. Dabei tragen aber gerade auch diese Instrumente dazu bei, auf der einen Seite das Instrumentarium âNeubÃ¼rgerpaketâ effektiv weiterzuentwickeln und es auf der anderen Seite langfristig auf stÃ¤dtischer und regionaler Ebene zu etablieren und damit zu einer effizienten Verkehrsabwicklung in der Region beizutragen. This paper focuses on attempts to gauge and assess the effectiveness of transport-policy measures which, through the use of information and communication, aim to influence the mobility behaviour of transport users, and thus also the modal split, in favour of ecomobility. The author concentrates on measures associated with âmobility packages for new citizensâ, which are illustrated by reference to two projects: Munichâs ânew citizens packageâ and the ânew citizens packageâ for the Munich region. It becomes clear that these projects both lack any clear positioning, and that there has been a failure to set out a differentiated system of targets and indicators, or to detail methods for monitoring and evaluation. And yet it is precisely such instruments which can, firstly, make a contribution to effective further development of the instrument which the ânew citizens packageâ embodies, and, secondly, help to establish it over the longer term at the municipal and regional levels and thus contribute to improving transport efficiency in the region.

The speed of change: motor vehicles and people in Africa, 1890-2000

Scipedia content — Thu, 21 Jan 2021 15:34:08 +0100

In the early 1900s the motor-vehicle (car, bus, lorry or motorcycle) was introduced in sub-Saharan Africa. Initially the plaything and symbol of colonial domination, the motor-vehicle transformed the economic and social life of the continent. Indeed, the motor-vehicle is arguably the single most important factor for change in Africa in the twentieth century. A factor for change that thus far has been neglected in research and literature. Yet its impact extends across the totality of human existence; from ecological devastation to economic advancement, from cultural transformation to political change, through a myriad of other themes. This edited volume of eleven contributions by historians, anthropologists and social and political scientists explores aspects of the social history and anthropology of the motor-vehicle in Africa.

10.2172/10169733

Scipedia content — Thu, 21 Jan 2021 15:28:01 +0100

A leak testing plan for a portion of the Liquid Low-Level Waste (LLLW) system at the Oak Ridge National Laboratory (ORNL) is provided in the two volumes that form this document. This plan was prepared in response to the requirements of the Federal Facilities Agreement (FFA) between the US Department of Energy and two other agencies, the US Environmental Protection Agency (EPA) and the Tennessee Department of Environment and Conservation (TDEC). The effective date of this agreement was 1 January 1992. The LLLW system is an interconnected complex of tanks and pipelines. The FFA distinguishes four different categories of tank and pipeline systems within this complex: new systems (Category A), doubly contained systems (Category B), singly contained systems (Category C), and inactive systems (Category D). The FFA`s specific requirements for leak testing of the Category C systems is addressed in this plan. The plan also addresses leak testing of the Category B portions of the LLLW system. Leak testing of the Category B components was brought into the plan to supplement the secondary containment design demonstration effort that is under way for these components.

A novel issue for the design of access interfaces in all optical slotted networks

Scipedia content — Thu, 21 Jan 2021 15:03:45 +0100

International audience; In this contribution, we consider a novel approach for efficiently supporting IP packets directly into a slotted optical wavelength- division-multiplexing (WDM) layer with several quality of service (QoS) requirements. The approach is based on aggregating IP packets, regardless of their final destinations, at fixed time intervals before the optical conversion phase. A QoS support access mechanism based on the strict priority discipline is evaluated by means of an analytical model. In this case, IP packet aggregation is performed in a loop manner by always beginning the aggregation cycle with the highest priority class. The aggregation cycle ends if the aggregate packet cannot accommodate more IP packets, or if the lowest priority class is reached. In order to overcome the drawbacks of the strict priority discipline, an algorithm depicting a probabilistic priority discipline is presented. The aggregation technique leads to increasing the filling ratio of an optical packet, and consequently, the bandwidth efficiency of an optical network, due to the multicast nature of the aggregation technique. In this context, the support of multicast in metropolitan area networks (MANs), with ring architectures, is presented. Furthermore, a new architecture is proposed in order to support the multicast aggregation technique in wide area networks (WANs)

Application of Simulated Annealing to Routing Problems in City Logistics

Scipedia content — Thu, 21 Jan 2021 15:01:31 +0100

The R & D activities to realize systems which provide road traffic information and route guidance have been conducted as core systems of Intelligent Transport Systems (ITS). However, the implementation of these systems will have less effect on freight transport unless logistics operation is rationalized in parallel to the development of ITS. On the other hand, according to the expansion of internet, information has been exchanged with extremely high speed and low cost. Nevertheless, goods must be moved in the real space. Ecommerce has caused the increase of door-to-door deliveries. The demands for high-quality delivery services such as small-amount high frequency deliveries with time windows have been made by many clients (including companies and individuals). The loading rate of trucks has decreased and the rate of freight transportation in total road traffic has increased. The rationalization in terms of increasing the loading rate and decreasing the total travel time is aimed not only for reducing operational costs in each freight carrier but also for relieving traffic congestion, saving energy and reducing the amount of CO2. Freight transportation in urban areas that is described above is called city logistics (Taniguchi et al. 2001). Many researches on routing problems have been appeared in the literature. Comprehensive and detailed explanations of theoretical models and solutions of them are given by Toth & Vigo (Toth & Vigo, 2002). On the other hand, in the context of city logistics, real routing problems should not be based under the assumption on the symmetry of the link costs of visiting customer j after customer i or customer i after customer j, pij=pji, and other related mathematical properties, as triangular property etc. This is due to the fact that in an urban environment routes using the streets have to account for one way streets, issues related to regulations at intersections. In addition, travel time might vary according to traffic conditions, that is to say, it might be time dependent. Moreover, in urban road networks, demands might be located on not only spots on streets but also streets themselves. This chapter is aimed for describing the original solution, which has been invented by the authors of this chapter, to routing problems in city logistics. At the beginning of this chapter, a variety of routing problems will be introduced and followed by the explanation of features of routing problems in city logistics. And then, a practical solution method, which is composed of a data model, transformation rules of a solution on the data model and an overall algorithm using Simulated Annealing for solving O pe n A cc es s D at ab as e w w w .ite ch on lin e. co m

Developing a Security Event Management System for Intermodal Transport

Scipedia content — Thu, 21 Jan 2021 14:30:23 +0100

Bremen, Federal State of Germany, is planning to set up a headquarter for GMES - Global Monitoring of Environment and Security. One goal of the Institute of Shipping Economics and Logistics (ISL) is to develop services for GMES to improve the security in intermodal container transport with emphasis on the maritime sector. ISL is developing a Security Event Management System which takes care of all security related events in the intermodal chain. The security system registers the schedule and transport information of a container and assigns a corridor for its transport. During the transport the system receives events which will be used for computing a security risk factor for each container, by considering restrictions like position with respect to the assigned corridor, duration of standstill and others. According to the value of the security risk factor the user will be informed using web services, EDI or email.

Heuristics and Biases in Travel Mode Choice

Scipedia content — Thu, 21 Jan 2021 14:20:09 +0100

. This study applies experimental methods to analyze travel mode choice. Two different scenarios are considered. In the first scenario, subjects have to decide whether to commute by car or by metro. Metro costs are fixed, while car costs are uncertain and determined by the joint effect of casual events and traffic congestion. In the second scenario, subjects have to decide whether to travel by car or by bus, both modes in which costs are determined by the combination of chance and congestion. Subjects receive feedback information on the actual travel times of both modes. We find that individuals exhibit a marked preference for cars, are inclined to confirm their first choice and demonstrate travel mode stickiness. We conclude that travel mode choice is subject to heuristics and biases that lead to robust deviations from rational choice.

Automobile Replacement: A Dynamic Structural Approach

Scipedia content — Thu, 21 Jan 2021 13:27:35 +0100

This paper specifies and estimates a structural dynamic model of consumer demand for new and used durable goods. Its primary contribution is to provide an explicit estimation procedure for transaction costs, which are crucial to capturing the dynamic nature of consumer decisions. In particular, transaction costs play a key role in determining consumer replacement behavior in both primary and secondary markets for durable goods. The unique data set used in this paper has been collected by the Italian Motor Registry and covers the period from 1994 to 2004. It includes information about sales dates for individual cars over time as well as the initial stock of cars in the sample period. Identification of transaction costs is achieved from the variation in the share of consumers choosing to hold a given car type each period, and from the share of consumers choosing to purchase the same car type that period. Specifically, I estimate a random coefficients discrete choice model that incorporates a dynamic optimal stopping problem in the spirit of Rust (1987). I apply this model to evaluate the impact of scrappage subsidies on the Italian automobile market in 1997 and 1998.

A New CAC Policy Based on Traffic Characterization in Cellular Networks

Scipedia content — Thu, 21 Jan 2021 13:23:40 +0100

The Call Admission Control (CAC) method presented in this paper is based on the statistical properties of the networkâs traffic variables. It probabilistically estimates the time until the release of a seized channel: the admission control depends on the computed mean remaining time averaged along all channels at a specific instant and on a time threshold. The policy produces a smooth transition between the QoS metrics, giving the operator the freedom to design the network at the desired QoS point. Another valuable property is that the algorithm is straightforward and fed only by simple teletraffic metrics: distribution and the first and second moments of Channel Holding Time (CHT). Simplicity is important for a CAC method because decisions for accepting or rejecting calls must be computed quickly and frequently.

Effects of a Kilometre Charge on Car Use, Car Ownership and Relocation

Scipedia content — Thu, 21 Jan 2021 13:04:47 +0100

Transport pricing is high on the political agenda throughout the world, but as the authors illustrate, governments seeking to implement this often face challenging questions and significant barriers. The associated policy and research questions cannot always be addressed adequately from a mono-disciplinary perspective. This book shows how a multi-disciplinary approach may lead to new types of analysis and insights, contributing to a better understanding of the intricacies of transport pricing and eventually to a potentially more effective and acceptable design of such policies. The study addresses important policy and research themes such as the possible motives for introducing road transport pricing and potential conflicts between these motives, behavioural responses to transport pricing for households and firms, the modelling of transport pricing, and the acceptability of pricing.

Remaining sites verification package for the 100 f 44 4 discovery pipeline in silica gel pit waste site reclassification form 2008 030

Scipedia content — Mon, 26 Oct 2020 15:48:07 +0100

The 100-F-44:4, Discovery Pipeline in Silica Gel Pit subsite is located in the 100-FR-1 Operable Unit of the Hanford Site, near the location of the former 110-F Gas Storage Tanks structure. The 100-F-44:4 subsite is a steel pipe discovered October 17, 2004, during trenching to locate the 118-F-4 Silica Gel Pit. Based on visual inspection and confirmatory investigation sampling data, the 100-F-44:4 subsite is a piece of non-hazardous electrical conduit debris. The 100-F-44:4 subsite supports unrestricted future use of shallow zone soil and is protective of groundwater and the Columbia River. No residual contamination exists within the deep zone. Therefore, no deep zone institutional controls are required.

Document type: Report

Remaining sites verification package for the 100 f 46 119 f stack sampling french drain waste site reclassification form 2008 021

Scipedia content — Mon, 26 Oct 2020 13:48:40 +0100

The 100-F-46 french drain consisted of a 1.5 to 3 m long, vertically buried, gravel-filled pipe that was approximately 1 m in diameter. Also included in this waste site was a 5 cm cast-iron pipeline that drained condensate from the 119-F Stack Sampling Building into the 100-F-46 french drain. In accordance with this evaluation, the confirmatory sampling results support a reclassification of this site to No Action. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Document type: Report

Remaining sites verification package for the 1607 f1 sanitary sewer system 124 f 1 and the 100 f 26 8 1607 f1 sanitary sewer pipelines waste sites waste site reclassification form 2005 004

Scipedia content — Mon, 26 Oct 2020 13:43:28 +0100

The 100-F-26:8 waste site consisted of the underground pipelines that conveyed sanitary waste water from the 1701-F Gatehouse, 1709-F Fire Station, and the 1720-F Administrative Office to the 1607-F1 septic tank. The site has been remediated and presently exists as an open excavation. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.

Document type: Report

Overview of the design construction and operation of interstate liquid petroleum pipelines

Scipedia content — Mon, 26 Oct 2020 13:37:29 +0100

The U.S. liquid petroleum pipeline industry is large, diverse, and vital to the nation's economy. Comprised of approximately 200,000 miles of pipe in all fifty states, liquid petroleum pipelines carried more than 40 million barrels per day, or 4 trillion barrel-miles, of crude oil and refined products during 2001. That represents about 17% of all freight transported in the United States, yet the cost of doing so amounted to only 2% of the nation's freight bill. Approximately 66% of domestic petroleum transport (by ton-mile) occurs by pipeline, with marine movements accounting for 28% and rail and truck transport making up the balance. In 2004, the movement of crude petroleum by domestic federally regulated pipelines amounted to 599.6 billion tonmiles, while that of petroleum products amounted to 315.9 billion ton-miles (AOPL 2006). As an illustration of the low cost of pipeline transportation, the cost to move a barrel of gasoline from Houston, Texas, to New York Harbor is only 3 cents per gallon, which is a small fraction of the cost of gasoline to consumers. Pipelines may be small or large, up to 48 inches in diameter. Nearly all of the mainline pipe is buried, but other pipeline components such as pump stations are above ground. Some lines are as short as a mile, while others may extend 1,000 miles or more. Some are very simple, connecting a single source to a single destination, while others are very complex, having many sources, destinations, and interconnections. Many pipelines cross one or more state boundaries (interstate), while some are located within a single state (intrastate), and still others operate on the Outer Continental Shelf and may or may not extend into one or more states. U.S. pipelines are located in coastal plains, deserts, Arctic tundra, mountains, and more than a mile beneath the water's surface of the Gulf of Mexico (Rabinow 2004; AOPL 2006). The network of crude oil pipelines in the United States is extensive. There are approximately 55,000 miles of crude oil trunk lines (usually 8 to 24 inches in diameter) in the United States that connect regional markets. The United States also has an estimated 30,000 to 40,000 miles of small gathering lines (usually 2 to 6 inches in diameter) located primarily in Texas, Oklahoma, Louisiana, and Wyoming, with small systems in a number of other oil producing states. These small lines gather the oil from many wells, both onshore and offshore, and connect to larger trunk lines measuring 8 to 24 inches in diameter. There are approximately 95,000 miles of refined products pipelines nationwide. Refined products pipelines are found in almost every state in the United States, with the exception of some New England states. These refined product pipelines vary in size from relatively small, 8- to 12-inch-diameter lines, to up to 42 inches in diameter. The overview of pipeline design, installation, and operation provided in the following sections is only a cursory treatment. Readers interested in more detailed discussions are invited to consult the myriad engineering publications available that provide such details. The two primary publications on which the following discussions are based are: Oil and Gas Pipeline Fundamentals (Kennedy 1993) and the Pipeline Rules of Thumb Handbook (McAllister 2002). Both are recommended references for additional reading for those requiring additional details. Websites maintained by various pipeline operators also can provide much useful information, as well as links to other sources of information. In particular, the website maintained by the U.S. Department of Energy's Energy Information Administration (EIA) (http://www.eia.doe.gov) is recommended. An excellent bibliography on pipeline standards and practices, including special considerations for pipelines in Arctic climates, has been published jointly by librarians for the Alyeska Pipeline Service Company (operators of the Trans-Alaska Pipeline System [TAPS]) and the Geophysical Institute/International Arctic Research Center, both located in Fairbanks (Barboza and Trebelhorn 2001), available electronically at http://www.gi.alaska.edu/services/library/pipeline.html codes. The Association of Oil Pipe Lines (AOPL) and the American Petroleum Institute (API) jointly provide an overview covering the life cycle of design, construction, operations, maintenance, economic regulation, and deactivation of liquid pipelines (AOPL/API 2007).

Document type: Report

Beluga coal gasification iser

Scipedia content — Mon, 26 Oct 2020 12:41:00 +0100

ISER was requested to conduct an economic analysis of a possible 'Cook Inlet Syngas Pipeline'. The economic analysis was incorporated as section 7.4 of the larger report titled: 'Beluga Coal Gasification Feasibility Study, DOE/NETL-2006/1248, Phase 2 Final Report, October 2006, for Subtask 41817.333.01.01'. The pipeline would carry CO{sub 2} and N{sub 2}-H{sub 2} from a synthetic gas plant on the western side of Cook Inlet to Agrium's facility. The economic analysis determined that the net present value of the total capital and operating lifecycle costs for the pipeline ranges from $318 to $588 million. The greatest contributor to this spread is the cost of electricity, which ranges from $0.05 to $0.10/kWh in this analysis. The financial analysis shows that the delivery cost of gas may range from $0.33 to $0.55/Mcf in the first year depending primarily on the price for electricity.

Document type: Report

Overview of interstate hydrogen pipeline systems

Scipedia content — Mon, 26 Oct 2020 12:23:59 +0100

The use of hydrogen in the energy sector of the United States is projected to increase significantly in the future. Current uses are predominantly in the petroleum refining sector, with hydrogen also being used in the manufacture of chemicals and other specialized products. Growth in hydrogen consumption is likely to appear in the refining sector, where greater quantities of hydrogen will be required as the quality of the raw crude decreases, and in the mining and processing of tar sands and other energy resources that are not currently used at a significant level. Furthermore, the use of hydrogen as a transportation fuel has been proposed both by automobile manufacturers and the federal government. Assuming that the use of hydrogen will significantly increase in the future, there would be a corresponding need to transport this material. A variety of production technologies are available for making hydrogen, and there are equally varied raw materials. Potential raw materials include natural gas, coal, nuclear fuel, and renewables such as solar, wind, or wave energy. As these raw materials are not uniformly distributed throughout the United States, it would be necessary to transport either the raw materials or the hydrogen long distances to the appropriate moreÂ Â» markets. While hydrogen may be transported in a number of possible forms, pipelines currently appear to be the most economical means of moving it in large quantities over great distances. One means of controlling hydrogen pipeline costs is to use common rights-of-way (ROWs) whenever feasible. For that reason, information on hydrogen pipelines is the focus of this document. Many of the features of hydrogen pipelines are similar to those of natural gas pipelines. Furthermore, as hydrogen pipeline networks expand, many of the same construction and operating features of natural gas networks would be replicated. As a result, the description of hydrogen pipelines will be very similar to that of natural gas pipelines. The following discussion will focus on the similarities and differences between the two pipeline networks. Hydrogen production is currently concentrated in refining centers along the Gulf Coast and in the Farm Belt. These locations have ready access to natural gas, which is used in the steam methane reduction process to make bulk hydrogen in this country. Production centers could possibly change to lie along coastlines, rivers, lakes, or rail lines, should nuclear power or coal become a significant energy source for hydrogen production processes. Should electrolysis become a dominant process for hydrogen production, water availability would be an additional factor in the location of production facilities. Once produced, hydrogen must be transported to markets. A key obstacle to making hydrogen fuel widely available is the scale of expansion needed to serve additional markets. Developing a hydrogen transmission and distribution infrastructure would be one of the challenges to be faced if the United States is to move toward a hydrogen economy. Initial uses of hydrogen are likely to involve a variety of transmission and distribution methods. Smaller users would probably use truck transport, with the hydrogen being in either the liquid or gaseous form. Larger users, however, would likely consider using pipelines. This option would require specially constructed pipelines and the associated infrastructure. Pipeline transmission of hydrogen dates back to late 1930s. These pipelines have generally operated at less than 1,000 pounds per square inch (psi), with a good safety record. Estimates of the existing hydrogen transmission system in the United States range from about 450 to 800 miles. Estimates for Europe range from about 700 to 1,100 miles (Mohipour et al. 2004; Amos 1998). These seemingly large ranges result from using differing criteria in determining pipeline distances. For example, some analysts consider only pipelines above a certain diameter as transmission lines. Others count only those pipelines that transport hydrogen from a producer to a customer (e.g., those pipelines designed for in-plant transport of hydrogen for use as feedstock or fuel are not counted). Operational status and hydrogen purity levels are also factors in defining these ranges. Hydrogen pipelines in the United States are predominantly along the Gulf Coast and connect major hydrogen producers with well-established, long-term customers. These hydrogen transmission systems pall by comparison with the 180,000-mile natural gas transmission pipeline. Since 1939, Germany has had a 130-mile pipeline carrying 20,000 lb/hour of hydrogen in a 10-inch pipe at 290 psi gauge (psig). The longest hydrogen pipeline in Europe is owned by Air Liquide and extends 250 miles from Northern France to Belgium. In theory, a blend of up to 20% hydrogen in natural gas can be transported without modifying natural gas pipelines (Oney et al. 1994). Â«Â le

Document type: Report

Preliminary geospatial analysis of arctic ocean hydrocarbon resources

Scipedia content — Mon, 26 Oct 2020 11:25:20 +0100

Ice coverage of the Arctic Ocean is predicted to become thinner and to cover less area with time. The combination of more ice-free waters for exploration and navigation, along with increasing demand for hydrocarbons and improvements in technologies for the discovery and exploitation of new hydrocarbon resources have focused attention on the hydrocarbon potential of the Arctic Basin and its margins. The purpose of this document is to 1) summarize results of a review of published hydrocarbon resources in the Arctic, including both conventional oil and gas and methane hydrates and 2) develop a set of digital maps of the hydrocarbon potential of the Arctic Ocean. These maps can be combined with predictions of ice-free areas to enable estimates of the likely regions and sequence of hydrocarbon production development in the Arctic. In this report, conventional oil and gas resources are explicitly linked with potential gas hydrate resources. This has not been attempted previously and is particularly powerful as the likelihood of gas production from marine gas hydrates increases. Available or planned infrastructure, such as pipelines, combined with the geospatial distribution of hydrocarbons is a very strong determinant of the temporal-spatial development of Arctic hydrocarbon resources. Significant unknowns decrease themoreÂ Â» certainty of predictions for development of hydrocarbon resources. These include: 1) Areas in the Russian Arctic that are poorly mapped, 2) Disputed ownership: primarily the Lomonosov Ridge, 3) Lack of detailed information on gas hydrate distribution, and 4) Technical risk associated with the ability to extract methane gas from gas hydrates. Logistics may control areas of exploration more than hydrocarbon potential. Accessibility, established ownership, and leasing of exploration blocks may trump quality of source rock, reservoir, and size of target. With this in mind, the main areas that are likely to be explored first are the Bering Strait and Chukchi Sea, in spite of the fact that these areas do not have highest potential for future hydrocarbon reserves. Opportunities for improving the mapping and assessment of Arctic hydrocarbon resources include: 1) Refining hydrocarbon potential on a basin-by-basin basis, 2) Developing more realistic and detailed distribution of gas hydrate, and 3) Assessing the likely future scenarios for development of infrastructure and their interaction with hydrocarbon potential. It would also be useful to develop a more sophisticated approach to merging conventional and gas hydrate resource potential that considers the technical uncertainty associated with exploitation of gas hydrate resources. Taken together, additional work in these areas could significantly improve our understanding of the exploitation of Arctic hydrocarbons as ice-free areas increase in the future.Â«Â le

Document type: Report

Early Experiences in Traffic Engineering Exploiting Path Diversity: A Practical Approach

Scipedia content — Mon, 26 Oct 2020 11:20:30 +0100

Recent literature has proved that stable dynamic routing algorithms have solid theoretical foundation that makes them suitable to be implemented in a real protocol, and used in practice in many different operational network contexts. Such algorithms inherit much of the properties of congestion controllers implementing one of the possible combination of AQM/ECN schemes at nodes and flow control at sources. In this paper we propose a linear program formulation of the multi-commodity flow problem with congestion control, under max-min fairness, comprising demands with or without exogenous peak rates. Our evaluations of the gain, using path diversity, in scenarios as intra-domain traffic engineering and wireless mesh networks encourages real implementations, especially in presence of hot spots demands and non uniform traffic matrices. We propose a flow aware perspective of the subject by using a natural multi-path extension to current congestion controllers and show its performance with respect to current proposals. Since flow aware architectures exploiting path diversity are feasible, scalable, robust and nearly optimal in presence of flows with exogenous peak rates, we claim that our solution rethinked in the context of realistic traffic assumptions performs as better as an optimal approach with all the additional benefits of the flow aware paradigm.

Document type: Report

Remaining sites verification package for the 100 f 26 15 miscellaneous pipelines associated with the 132 f 6 1608 f waste water pumping station waste site reclassification form 2007 031

Scipedia content — Mon, 26 Oct 2020 11:20:17 +0100

The 100-F-26:15 waste site consisted of the remnant portions of underground process effluent and floor drain pipelines that originated at the 105-F Reactor. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Document type: Report

Analysis of main steam isolation valve leakage in design basis accidents using melcor 1 8 6 and radtrad

Scipedia content — Mon, 26 Oct 2020 10:31:23 +0100

Analyses were performed using MELCOR and RADTRAD to investigate main steam isolation valve (MSIV) leakage behavior under design basis accident (DBA) loss-of-coolant (LOCA) conditions that are presumed to have led to a significant core melt accident. Dose to the control room, site boundary and LPZ are examined using both approaches described in current regulatory guidelines as well as analyses based on best estimate source term and system response. At issue is the current practice of using containment airborne aerosol concentrations as a surrogate for the in-vessel aerosol concentration that exists in the near vicinity of the MSIVs. This study finds current practice using the AST-based containment aerosol concentrations for assessing MSIV leakage is non-conservative and conceptually in error. A methodology is proposed that scales the containment aerosol concentration to the expected vessel concentration in order to preserve the simplified use of the AST in assessing containment performance under assumed DBA conditions. This correction is required during the first two hours of the accident while the gap and early in-vessel source terms are present. It is general practice to assume that at {approx}2hrs, recovery actions to reflood the core will have been successful and that further core damage can be avoided. moreÂ Â» The analyses performed in this study determine that, after two hours, assuming vessel reflooding has taken place, the containment aerosol concentration can then conservatively be used as the effective source to the leaking MSIV's. Recommendations are provided concerning typical aerosol removal coefficients that can be used in the RADTRAD code to predict source attenuation in the steam lines, and on robust methods of predicting MSIV leakage flows based on measured MSIV leakage performance. Â«Â le

Document type: Report

Comparing Existing Pipeline Networks with the Potential Scale of Future U.S. CO2 Pipeline Networks

Scipedia content — Mon, 26 Oct 2020 10:19:37 +0100

AbstractInterest is growing regarding the potential size of a future U.S.-dedicated carbon dioxide (CO2) pipeline infrastructure if carbon dioxide capture and storage (CCS) technologies are commercially deployed on a large scale within the United States. This paper assesses the potential scale of the CO2 pipeline system needed under two hypothetical climate policies (WRE450 and WRE550 stabilization scenarios); a comparison is then made to the extant U.S. pipeline infrastructures used to deliver CO2 for enhanced oil recovery and to move natural gas and liquid hydrocarbons from areas of production and importation to markets. The analysis reveals that between 11,000 and 23,000 additional miles of dedicated CO2 pipeline might be needed in the United States before 2050 across these two cases. While either case represents a significant increase over the 3900 miles that comprise the existing national CO2 pipeline infrastructure, it is important to realize that the demand for additional CO2 pipeline capacity will unfold relatively slowly and in a geographically dispersed manner as new dedicated CCS-enabled power plants and industrial facilities are brought online. During the period 2010Â2030, this analysis indicates growth in the CO2 pipeline system on the order of a few hundred to less than 1000 miles per year. By comparison, during the period 1950Â2000, the U.S. natural gas pipeline distribution system grew at rates that far exceed these growth projections for a future CO2 pipeline network in the U.S. This analysis indicates that the need to increase the size of the existing dedicated CO2 pipeline system should not be seen as a major obstacle for the commercial deployment of CCS technologies in the United States. While there could be issues associated with siting specific segments of a larger national CO2 pipeline infrastructure, the sheer scale of the required infrastructure should not be seen as representing a significant impediment to U.S. deployment of CCS technologies.

Document type: Report

Complexity results for throughput and latency optimization of replicated and data-parallel workflows

Scipedia content — Mon, 26 Oct 2020 10:14:43 +0100

International audience; Mapping applications onto parallel platforms is a challenging problem, even for simple application patterns such as pipeline or fork graphs. Several antagonist criteria should be optimized for workflow applications, such as throughput and latency (or a combination). In this paper, we consider a simplified model with no communication cost, and we provide an exhaustive list of complexity results for different problem instances. Pipeline or fork stages can be replicated in order to increase the throughput by sending consecutive data sets onto different processors. In some cases, stages can also be data-parallelized, i.e. the computation of one single data set is shared between several processors. This leads to a decrease of the latency and an increase of the throughput. Some instances of this simple model are shown to be NP-hard, thereby exposing the inherent complexity of the mapping problem. We provide polynomial algorithms for other problem instances. Altogether, we provide solid theoretical foundations for the study of mono-criterion or bi-criteria mapping optimization problems.

Document type: Report

Extension upgrading methane using ultra fast thermal swing adsorption

Scipedia content — Mon, 26 Oct 2020 10:14:12 +0100

The need for cost effective technologies for upgrading coal mine methane to pipeline quality natural gas is becoming ever greater. The current work presents and investigates a new approach to reduce the impact of the most costly step in the conventional technology, nitrogen rejection. The proposed approach is based on the Velocys microchannel platform, which is being developed to commercialize compact and cost efficient chemical processing technology. For this separation, ultra fast thermal swing sorption is enabled by the very high rates of heat and mass transfer inherent in microchannel processing. In a first phase of the project solid adsorbents were explored. Feasibility of ultrafast thermal swing was demonstrated but the available adsorbents had insufficient differential methane capacity to achieve the required commercial economics. In a second phase, ionic liquids were adopted as absorbents of choice, and experimental work and economic analyses, performed to gauge their potential, showed promise for this novel alternative. Final conclusions suggest that a combination of a required cost target for ionic liquids or a methane capacity increase or a combination of both is required for commercialization.

Document type: Report

On Packet Switches With Infinite Storage

Scipedia content — Mon, 26 Oct 2020 10:06:07 +0100

Most prior work on congestion in datagram systems focuses on buffer management. We find it illuminating to consider the case of a packet switch with infinite storage. Such a packet switch can never run out of buffers. It can, however, still become congested. The meaning of congestion in an infinite-storage system is explored. We demonstrate the unexpected result that a datagram network with infinite storage, first-in, first-out queueing, at least two packet switches, and a finite packet lifetime will, under overload, drop all packets. By attacking the problem of congestion for the infinite-storage case, we discover new solutions applicable to switches with finite storage.

Document type: Report

Remaining sites verification package for the 100 b 21 2 subsite 100 b c discovery pipeline ds 100bc 002 waste site reclassification form 2008 003

Scipedia content — Mon, 26 Oct 2020 09:57:02 +0100

The 100-B-21:2 waste site consists of the immediate area of the DS-100BC-02 pipeline. In accordance with this evaluation, the confirmatory and verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

Document type: Report

Advanced integration of multi scale mechanics and welding process simulation in weld integrity assessment

Scipedia content — Thu, 22 Oct 2020 15:30:38 +0200

The potential to save trillions of BTUs in energy usage and billions of dollars in cost on an annual basis based on use of higher strength steel in major oil and gas transmission pipeline construction is a compelling opportunity recognized by both the US Department of Energy (DOE). The use of high-strength steels (X100) is expected to result in energy savings across the spectrum, from manufacturing the pipe to transportation and fabrication, including welding of line pipe. Elementary examples of energy savings include more the 25 trillion BTUs saved annually based on lower energy costs to produce the thinner-walled high-strength steel pipe, with the potential for the US part of the Alaskan pipeline alone saving more than 7 trillion BTU in production and much more in transportation and assembling. Annual production, maintenance and installation of just US domestic transmission pipeline is likely to save 5 to 10 times this amount based on current planned and anticipated expansions of oil and gas lines in North America. Among the most important conclusions from these studies were: While computational weld models to predict residual stress and distortions are well-established and accurate, related microstructure models need improvement. Fracture Initiation Transition Temperature (FITT) Master Curve properly more » predicts surface-cracked pipe brittle-to-ductile initiation temperature. It has value in developing Codes and Standards to better correlate full-scale behavior from either CTOD or Charpy test results with the proper temperature shifts from the FITT master curve method. For stress-based flaw evaluation criteria, the new circumferentially cracked pipe limit-load solution in the 2007 API 1104 Appendix A approach is overly conservative by a factor of 4/?, which has additional implications. . For strain-based design of girth weld defects, the hoop stress effect is the most significant parameter impacting CTOD-driving force and can increase the crack-driving force by a factor of 2 depending on strain-hardening, pressure level as a % of SMYS, and flaw size. From years of experience in circumferential fracture analyses and experimentation, there has not been sufficient integration of work performed for other industries into analogous problems facing the oil and gas pipeline markets. Some very basic concepts and problems solved previously in these fields could have circumvented inconsistencies seen in the stress-based and strain-based analysis efforts. For example, in nuclear utility piping work, more detailed elastic-plastic fracture analyses were always validated in their ability to predict loads and displacements (stresses and strains). The eventual implementation of these methodologies will result in acceleration of the industry adoption of higher-strength line-pipe steels. « le

Document type: Report

Accreditation of Vocational Learning Outcomes: Perspectives for a European Transfer

Scipedia content — Wed, 14 Oct 2020 16:35:10 +0200

The fundamental principle that EQF and ECVET have in common is the description of qualifications in terms of learning outcomes. The background for implementing this outcome-based approach in the European education and training systems, however, is quite diverse. This situation is addressed by the CREDIVOC project, which involves partners from Austria, Finland, France, Germany and Ireland and focuses on the identification, testing and transfer of instruments that can be used for the recognition and accreditation of learning outcomes from initial and continuing vocational education and training for further education. The present publication is the major outcome of the first phase of the project, which aimed at the production of a general overview of the accreditation procedures and instruments in the partner countries. To this end, national case studies concerning the accreditation of vocational learning outcomes in Austria, Finland, France, Germany and Ireland have been carried out by the project partners. In order to allow for comparison between the different national approaches a common analytical framework was adopted. The criteria focus especially on the type of recognition (individual vs. blanket recognition) and the methodology of the assessment tools or instruments used. A synthesis report summarises the results of the national case studies and draws some conclusions as to what types of accreditation procedures and instruments might be appropriate for improving the transparency of qualifications and the mobility between educational programmes in Europe. (DIPF/orig.) Das gemeinsame Grundprinzip von EQR und ECVET ist die Beschreibung von Qualifikationen durch Lernergebnisse. Die Ausgangsbedingungen für eine Umsetzung dieses ergebnisorientierten Ansatzes in den europäischen Systemen der allgemeinen und beruflichen Bildung sind jedoch sehr unterschiedlich. Dieser Problematik widmet sich das Projekt CREDIVOC, das von Partnern aus Deutschland, Finnland, Frankreich, Irland und Österreich durchgeführt wird und die Identifikation, die Erprobung und den Transfer von Instrumenten zur Anrechnung beruflicher Lernergebnisse auf weiterführende Bildungsgänge zum Gegenstand hat. Die vorliegende Publikation ist das Ergebnis der ersten Projektphase, die der Herstellung einer allgemeinen Übersicht über die Anrechnungsverfahren und instrumente in den Partnerländern gewidmet war. Zu diesem Zweck haben die Partner nationale Fallstudien zur Anrechnung beruflicher Lernergebnisse in den Partnerländern durchgeführt. Um einen Vergleich der Ergebnisse zu ermöglichen, wurde ein gemeinsames Vergleichsraster erarbeitet, dessen Kriterien in der Hauptsache die Art der Anrechnung (individuelle vs. pauschale Anrechnung) sowie die Methodik der Verfahren betreffen. Ein abschließender Synthesebericht fasst die Ergebnisse der einzelnen Länderkapitel zusammen und entwickelt Schlussfolgerungen zu der Frage, welche Ansätze und Instrumente der Anrechnung beruflicher Lernergebnisse besonders geeignet sind, die Transparenz von Qualifikationen und die Bildungsmobilität in Europa zu verbessern. (DIPF/Orig.)

Document type: Book

AUV Application for Inspection of Underwater Communications

Scipedia content — Wed, 14 Oct 2020 16:33:59 +0200

Regular inspection of underwater communications (pipelines and cables) is actual problem of modern oil and gas industry. Specially equipped vessels, towed underwater devices and remote operated vehicles /ROV/ are applied for these purposes as usually, but quality of acquired data does not always allow revealing emergencies at the proper time. Spot inspections by ROVs give difficultly comparable data (Baker, 1991; Murray, 1991). The perspective solution of the problem is autonomous underwater vehicles /AUV/ application as the intellectual carrier of research equipment (Evans et al., 2003; Kojima et al., 1997). According (Ageev, 2005) the main goals of pipeline and cables inspection are: 1. more accurate position determination (searching and tracking); 2. pipe sagging and freespan detection and measurement; 3. terrain survey on each side of communication by means of high frequency side scan sonar /HF SSS/ and detection of extraneous objects; 4. detection of damages; 5. leakage detection of transported substances (for pipelines). The pipeline and cable inspection by means of AUV includes two stages: preliminary (communication search and detection) and the main (motion along the communication with carrying out of necessary measurements, i.e. tracking). Exact mutual orientation of AUV and inspected object is required in real time during the tracking stage. To solve inspection tasks AUV should be equipped with reliable detection systems for inspected object recognition. Video, electromagnetic and echo-sounder data can be used for these purposes. Each of these devices demonstrates optimal results for certain classes of objects in appropriate conditions. For example, metal pipelines have the significant sizes and can be detected by all listed above devices. While underwater cables have a small diameter, because of this applicability of acoustic methods is limited (Petillot et al., 2002). Process of communications search and detection is complicated, as a rule, with a poor visibility of the given objects (strewed with a ground, silted or covered by underwater flora and fauna). Experiments with the use of AUV for inspection of underwater communications have been carried out for a long time. Usually only one instrument, which AUV is equipped with, is used for object detection. O pe n A cc es s D at ab as e w w w .in te ch w eb .o rg

Document type: Part of book or chapter of book

Further Steps towards Driver Modeling According to the Bayesian Programming Approach

Scipedia content — Wed, 14 Oct 2020 16:29:50 +0200

The Human Centered Design (HCD) of Partial Autonomous Driver Assistance Systems (PADAS) requires Digital Human Models (DHMs) of human control strategies for simulating traffic scenarios. We describe first results to model lateral and longitudinal control behavior of drivers with simple dynamic Bayesian sensory-motor models according to the Bayesian Programming (BP) approach: Bayesian Autonomous Driver (BAD) models. BAD models are learnt from multivariate time series of driving episodes generated by single or groups of users. The variables of the time series describe phenomena and processes of perception, cognition, and action control of drivers. BAD models reconstruct the joint probability distribution (JPD) of those variables by a composition of conditional probability distributions (CPDs). The real-time control of virtual vehicles is achieved by inferring the appropriate actions under the evidence of sensory percepts with the help of the reconstructed JPD.

Document type: Part of book or chapter of book

Probabilistic, and Empirical Grounded Modeling of Agents in Partial Cooperative (Traffic) Scenarios

Scipedia content — Wed, 14 Oct 2020 16:20:38 +0200

The Human Centered Design (HCD) of Partial Autonomous Driver Assistance Systems (PADAS) requires Digital Human Models (DHMs) of human control strategies for simulations of traffic scenarios. The scenarios can be regarded as problem situations with one or more (partial) cooperative problem solvers. According to their roles models can be descriptive or normative . We present new model architectures and applications and discuss the suitability of dynamic Bayesian networks as control models of traffic agents: Bayesian Autonomous Driver (BAD) models. Descriptive BAD models can be used for simulating human agents in conventional traffic scenarios with Between-Vehicle-Cooperation (BVC) and in new scenarios with In-Vehicle-Cooperation (IVC). Normative BAD models representing error free behavior of ideal human drivers (e.g. driving instructors) may be used in these new IVC scenarios as a first Bayesian approximation or prototype of a PADAS.

Document type: Part of book or chapter of book