Documents published in 2003 : Scipedia

INVESTIGATING THE ADJUSTMENT FACTOR FOR PROTECTED LEFT TURNS FROM A SHARED LANE
V. Porikou, J. Golias

Collection of open articles in transport research (2004). Vol. 2004, 3

Abstract
The purpose of this paper is to propose a more accurate method for the estimation of the left-turn adjustment factor for protected left turns at traffic signals. Research on the left-turn adjustment factor for two-lane approaches with protected left turns from a shared lane, gave results that differ from those of the HCM. Based on extended field measurements, the model proposed in this paper relates the left-turn adjustment factor for protected left turns from a shared lane to a number of traffic parameters. Such as the distribution of vehicles in the lanes, the mean volume per lane and the proportion of the left-turning vehicles. Document type: Article
Abstract
The purpose of this paper is to propose a more accurate method for the estimation of the left-turn adjustment factor for protected left turns at traffic signals. Research [...]
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User-level QoS and traffic engineering for 3G wireless 1xEV-DO systems
H. Viswanathan, P. Whiting, K. Clarkson, S. Borst, J. Graybeal

Collection of closed articles in transport research (2003). Vol. 2003, 6

Abstract
Third-generation (3G) wireless systems such as 3G1X, 1×EV-DO, and 1xEV-DV provide support for a variety of high-speed data applications. The success of these services critically relies on the capability to ensure an adequate quality of service (QoS) experience to users at an affordable price. With wireless bandwidth at a premium, traffic engineering and network planning play a vital role in addressing these challenges. We present models and techniques that we have developed for quantifying the QoS perception of 1×EV-DO users generating file transfer protocol (FTP) or Web browsing sessions. We show how user-level QoS measures may be evaluated by means of a Processor-Sharing model that explicitly accounts for the throughput gains from multi-user scheduling. The model provides simple analytical formulas for key performance metrics such as response times, blocking probabilities, and throughput. Analytical models are especially useful for network deployment and in-service tuning purposes due to the intrinsic difficulties associated with simulation-based optimization approaches. © 2003 Lucent Technologies Inc.
Abstract
Third-generation (3G) wireless systems such as 3G1X, 1×EV-DO, and 1xEV-DV provide support for a variety of high-speed data applications. The success of these services critically [...]
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New directions for ATC training: A discussion
M. Cavcar, A. Cavcar

Collection of closed articles in transport research (2004). Vol. 2004, 7

Abstract
WOS: 000221285100002 The air traffic control system is changing due to implementation of automation systems to avoid congestion and to increase safety, efficiency, and economy of flights. Consequently, the nature of an air traffic controller's job is also changing. Therefore, knowledge requirements of air traffic controllers should be revised. In this article, we discuss the need for revision. Then we propose revised knowledge requirements and compare them with United States and French practices. Based on findings of comparison, we propose that colleges should provide air traffic control specialist training despite the challenges due to the nature of the air traffic control job.
Abstract
WOS: 000221285100002 The air traffic control system is changing due to implementation of automation systems to avoid congestion and to increase safety, efficiency, and economy [...]
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Assessment of Large-Scale Action Plans to reduce external Background Noise in School Buildings
R. Romano, P. Lembo, L. Maffei, R. Dragonetti

Collection of closed articles in transport research (2004). Vol. 2004, 6

Abstract
In this paper the authors report on a simplified procedure, developed in a Geographical Information System (GIS) environment, for the localization of school buildings characterized by high indoor background noise levels due to the outside noise sources. The noise sources include road, rail, and air traffic and other human activities (playgrounds, commercial activities, etc). Starting with the knowledge of noise pollution levels in the urban areas where the educational premises are sited, indoor background noise levels are obtained by adding two corrective terms; the first term takes into account for road configuration sound attenuation and the second one for facade sound insulation. For each educational building, a priority index is assigned on the basis of fixed objective parameters. The developed procedure has been applied to case studies of school buildings in Naples. The procedure promises a practical, low cost tool for municipal administrations to assess critical educational buildings and to plan noi...
Abstract
In this paper the authors report on a simplified procedure, developed in a Geographical Information System (GIS) environment, for the localization of school buildings characterized [...]
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ADAS applications for improving traffic safety
K. Wevers, M. Lu, R. Heijden, T. Heijer

Collection of closed articles in transport research (2004). Vol. 2004, 5

Abstract
Governments in several European countries, and the EU have set challenging targets for the improvement of road traffic safety by the year 2010. In the Netherlands a program for infrastructure measures was launched, to meet the Dutch targets. The ongoing developments in the field of ITS applications seem however to offer viable alternatives for large-scale infrastructure reconstruction. This paper explores the feasibility of five ADAS applications (navigation, speed assistance, collision avoidance, intersection support and lane keeping) to complement or partly substitute infrastructure measures to reach the stated goals. State-of-the-art and the potential of enabling technologies like positioning, radar, laser, video imaging and communication are analysed from a technical perspective. Technical issues relating to large-scale dedicated ADAS implementation for traffic safety, as well as related policy issues are discussed.
Abstract
Governments in several European countries, and the EU have set challenging targets for the improvement of road traffic safety by the year 2010. In the Netherlands a program [...]
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Impact of aircraft performance differences on fuel consumption of aircraft in air traffic management environment
A. Cavcar, M. Cavcar

Collection of closed articles in transport research (2004). Vol. 2004, 2

Abstract
WOS: 000224656300007 Performance differences between the aircraft types are natural and they inevitably cause problems in the air traffic system, particularly when slower aircraft types are followed by faster types in a climb or cruise queue. This paper presents the excess fuel consumption impact of aircraft performance differences in the air traffic environment. For this purpose, both climb and cruise phases of a flight mission are analyzed. Revision of the airworthiness regulations and air traffic procedures are suggested. The need for a flight level - cruise performance categorization is also recommended.
Abstract
WOS: 000224656300007 Performance differences between the aircraft types are natural and they inevitably cause problems in the air traffic system, particularly when slower [...]
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The Archaeology of the Canal Warehouses of North-West England and the Social Archaeology of Industrialisation
M. Nevell

Collection of closed articles in transport research (2003). Vol. 2003, 3

Abstract
North- West England was the site of Britain's first canal and of one of the last true canal warehouses. The Duke's Warehouse in the Castlefield Canal Basin in Manchester was the first canal warehouse to have the classic design features of internal canal arms, multi-storeys, split level\\ud loading, terracing and water powered hoists, and was built between 1769 and 1771. The Great Northern Warehouse, in the centre of Manchester, was the last of the monumental road, rail and canal interchanges to be built in the Victorian period. Finished in 1898, it marked the close of the canal warehouse tradition and the beginning of motorised road transport storage. Between the two buildings were nearly 130 years of innovation and change. With at least 58\\ud surviving canal warehouses across the region, from Kendal in the north to Bunbury in the south, North- West England contains one of the largest, and most important, groups of canal warehouses in Europe (Figures 1 and 2). As general purpose redistribution centres they were a vital element in feeding the rapidly growing industrial urban populations of the region. Furthermore, their design influenced the building of the first railway warehouses, and later the textile warehouse, and although the canals were superseded by the railway, the canal warehouse remained an important element of the transport economy until the arrival of road haulage in the 1920s. This paper is based upon research undertaken by the author in 2000 and 2001 as part of the\\ud Tameside Archaeological Survey.
Abstract
North- West England was the site of Britain's first canal and of one of the last true canal warehouses. The Duke's Warehouse in the Castlefield Canal Basin in Manchester was [...]
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THE MODELLING OF FACTORS DETERMINING THE GOODS AND TRAFFIC FLOWS MOVEMENT IN A LOGISTICAL SYSTEM
A. Jaržemskis

Collection of open articles in transport research (2003). Vol. 2003, 6

Abstract
The purpose of this atticle is to model the factors determining the goods traffic along the logistical channels located in various geopolitical regions on the basis of the transport network. The attention is focused on theoretical presumption of logistical channels formation in a logistical system. In this modeling the factors which determine the formation of the goods flow along the subsystems of the entire logistical system from the geopolitical point of view are defined. In this model the competitiveness of a logistical channel is determined by its technological, economical, legal characteristics as well as the length of the entire channel. The states, having the model provided, can evaluate the characteristics of the elements of the logistical channel and seek for the optimum ways to improve them. While planning the allocation of investments to improve the characteristics of separate elements of a logistical channel, it is a matter of utmost impmtance to consider the characteristics and their prospects of the entire logistical channel, a part of which stretches along the other states. It is very important for the Baltic States which are situated at the intersection of transit goods flows and logistical channels. First Published Online: 19 Dec 2011 Document type: Article
Abstract
The purpose of this atticle is to model the factors determining the goods traffic along the logistical channels located in various geopolitical regions on the basis of the [...]
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Child Farm Labor: The Wealth Paradox
C. Heady, S. Bhalotra

Collection of open articles in transport research (2003). Vol. 2003, 5

Abstract
This article is motivated by the remarkable observation that children of land-rich households are often more likely to be in work than the children of land-poor households. The vast majority of working children in developing economies are in agricultural work, predominantly on farms operated by their families. Land is the most important store of wealth in agrarian societies, and it is typically distributed very unequally. These facts challenge the common presumption that child labor emerges from the poorest households. This article suggests that this apparent paradox can be explained by failures of the markets for labor and land. Credit market failure will tend to weaken the force of this paradox. These effects are modeled and estimates obtained using survey data from rural Pakistan and Ghana. The main result is that the wealth paradox persists for girls in both countries, whereas for boys it disappears after conditioning on other covariates. Document type: Article
Abstract
This article is motivated by the remarkable observation that children of land-rich households are often more likely to be in work than the children [...]
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Thermal conditions of road pavements and their influence on motor traffic
D. Ďygas, A. Laurinavičius

Collection of open articles in transport research (2003). Vol. 2003, 4

Abstract
The article presents the analysis of climatic conditions in the Republic of Lithuania and describes their influence on road asphalt concrete pavement. Dependence of the main properties of asphalt concrete mixtures on tempera~re is described with the help of carried out experiments. Research findings show that the probability of plastic defomations (rutting and corrugation) in asphalt concrete pavement is higher when the pavement temperature IS 20-40 C. Ptactical application of the presented conclusions and recommendations will enable to reduce the occurrence of undesirable deformations in asphalt concrete pavements and to improve traffic conditions on the roads. First Published Online: 19 Dec 2011 Document type: Article
Abstract
The article presents the analysis of climatic conditions in the Republic of Lithuania and describes their influence on road asphalt concrete pavement. Dependence of the main [...]
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EXAMINATION OF THE EMERGENCY MEDICAL RESPONSE SYSTEM IN KOREA AND SUGGESTIONS FOR IMPROVEMENTS RELATING TO TRANSPORT
S. Oh

Collection of open articles in transport research (2004). Vol. 2004, 2

Abstract
Emergency medical response system in Korea was launched in 1982 for the improvement of national welfare. Emergency medical response system is made up of accident scene phase, transport phase, hospital phase, and communication system. The accident scene and transportation phase are mainly conducted by the 119 Rescue team and the hospital phase takes place at emergency medical centers. The communication system is managed by emergency medical information center. This research focuses on the examination of current emergency medical response system related to the transport of emergency vehicles and suggests some transport-related ideas to improve the system in Korea. The study aimed to investigate the present emergency medical response system and identify problems, questionnaire survey and literature review were carried. The ideas include the improvement of emergency information flow and the development of preferential treatment methods for emergency vehicles. To improve the emergency information flow, this research studied the bridge between emergency medical information center and traffic information center and proposed the efficient utilization of traffic information for the better treatment of an emergency. When it comes to the movement of emergency vehicles, various preferential treatment methods were suggested. Document type: Article
Abstract
Emergency medical response system in Korea was launched in 1982 for the improvement of national welfare. Emergency medical response system is made up of accident scene phase, [...]
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Offsite radiological consequence analysis for the waste transfer leak
B. Zimmerman

Collection of restricted reports in transport research (2021). Vol. 2003, 3

Abstract
This document quantifies the offsite radiological consequence of the bounding waste transfer leak accident for comparison with the 25 rem Evaluation Guideline established in DOE-STD-3009, Appendix A. The bounding waste transfer leak accident is a large pipe break into a pit. The calculation offsite dose does not challenge the Evaluation Guidelines. Revision 2 incorporated comments received from the office of River Protection. The purpose of this calculation note is to document calculations performed in support of the evaluation of the bounding representative accident scenario for the waste transfer leak accident. The waste transfer leak accident has two representative accident scenarios: the fine spray into the air scenario and the large pipe break into a pit scenario. Both of these scenarios are evaluated in this calculation note, and a determination is made that the large pipe break into a pit scenario is bounding. Only the offsite radiological consequences are considered by this calculation note.
Abstract
This document quantifies the offsite radiological consequence of the bounding waste transfer leak accident for comparison with the 25 rem Evaluation Guideline established [...]
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Evaluation of Hose in Hose transfer line service life
O. Eagle

Collection of restricted reports in transport research (2021). Vol. 2003, 2

Abstract
This document presents a determination for the amount of expected service life from Hose-in-Hose Transfer Lines based on vendor information and past HIHTL experience. Based on the information presented in this report and referenced documentation, we conclude the service life of the inner hose establishes the limits of service life for the finished assemblies. Since the process and environmental conditions to which the transfer line is subjected will not adversely affect the hose, the effective service life is that stated by the vendor--three years from the date of initial transfer. Transfer line assemblies have a shelf life of seven years from the date of hose manufacture, if stored in accordance with Section 2.1. This evaluation provides documentation showing that a three year service life has been justified. In the event that transfer lines are to be operated after three years from the date of initial transfer and within the shelf life of seven years, they must be reevaluated for their ability to perform intended functions.
Abstract
This document presents a determination for the amount of expected service life from Hose-in-Hose Transfer Lines based on vendor information and past HIHTL experience. Based [...]
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Dual Earners, Urban Labour Markets and Housing Demand
J. Rouwendal, J. Straaten

Collection of closed chapters of books in transport research (2021). Vol. 2004, 4

Abstract
This chapter replicates Costa and Kahn's analysis of locational choices of highly educated couples for the Netherlands. We find increasing concentration of such power couples in the urbanised western part of the country. This trend occurs in spite of the absence of an urban wage premium and the concentration of traffic congestion there. We find that power couples locate more often in medium sized and larger cities than otherwise comparable households and that they are relatively often owner-occupiers and live in more expensive houses. Their commuting time is relatively short when it is taken into account that it is more difficult for those households to find suitable arrangements of employment and residence than it is for single earner households. A likely explanation for these findings is that power couples use their relatively large purchasing power to outbid other households from locations that are especially attractive to them, as is predicted by household location theory.
Abstract
This chapter replicates Costa and Kahn's analysis of locational choices of highly educated couples for the Netherlands. We find increasing concentration of such power [...]
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Towards sustainable aviation
D. Raper, P. Upham, C. Thomas, J. Maughan

Collection of closed chapters of books in transport research (2021). Vol. 2003, 4

Abstract
Preface * Part 1: Trends and Issues Introduction: Perspectives on Sustainability and Aviation * Organizational and Growth Trends in Air Transport * the Social and Economic Benefits of Aviation * Aircraft Noise, Community Relations and Stakeholder Involvement * Part 2: Mitigations and Potential Solutions - Environmental Management and the Aviation Industry * The Potential for Modal Substitution * Air Freight and Global Supply Chains: the Environmental Dimension * The Potential Offered by Aircraft and Engine Technologies * Climate Policy for Civil Aviation: Actors, Policy Instruments and the Potential for Emissions Reductions * Part 3: Multisector Commentaries -Multisector Commentaries on Sustainability and Aviation * Economic Aspects of Sustainability and UK Aviation Sustainable Aviation: Implications for Economies in Transition * Key Issues in Aviation Environmental Policy-Making * Towards Sustainable Aviation? * Aircraft Noise: The NGO Perspective * Environmental and Economic Factors in Airport Capacity * Potential Improvements to Air Traffic Management * Making Aviation Less Unsustainable: Some Pointers to the Way Ahead * Sustainable Aviation: What do you Mean? * Sustainability and Aviation: Problems and Solutions * Airlines and Sustainable Development * the Case for 'No growth' * Conclusion * Index
Abstract
Preface * Part 1: Trends and Issues Introduction: Perspectives on Sustainability and Aviation * Organizational and Growth Trends in Air Transport * the Social and Economic [...]
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Major Accident Risks of HazMat Transport by Rail between Industrial Sites. A Case Study in Sicily
G. Antonioni, G. Spadoni, M. Milazzo, G. Maschio

Collection of closed conferences in transport research (2021). Vol. 2004, 8

Abstract
The presence on a territory of industrial activities where chemical substances are stored and manufactured necessarily involves the transport of hazardous substances. Transportation of dangerous goods may often involve long distances to reach the final destination or other industrial sites. In Italy there are several examples of this type of situation including the case of Sicily. In a previous work the risk due to the transport of dangerous goods in the whole island of Sicily has been analysed and evaluated, with the aim to test the risk evaluation procedure and its recent refining on a large scale, since this procedure was previously applied only for small areas (usually urban areas). Being the test successfully, this work will focus on the transport of ammonia by rail, trying to use detailed input data both for the accidental frequency and for meteorological data. This route has been chosen because local authority finds it particularly dangerous because of the obsolescence of the rail track, but unfortunately we couldn’t get historical accident data on it.
Abstract
The presence on a territory of industrial activities where chemical substances are stored and manufactured necessarily involves the transport of hazardous substances. Transportation [...]
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Post-processing of data generated by a chaotic pipelined ADC for the robust generation of perfectly random bitstreams
G. Setti, S. Callegari, R. Rovatti, S. Poli

Collection of closed conferences in transport research (2021). Vol. 2004, 7

Abstract
We review a true random number generator which internally exploits a pipeline analog-to-digital converter modified to operate in chaotic mode. Contrarily to other true random number generators it is not based on the explicit observation of noisy physical quantities, freeing the designer from subtle technology-dependent details. In ideal conditions the model can be formally proven to deliver perfectly uncorrelated output sequences by itself. Here we thoroughly investigate the effects of implementation errors and we introduce a data-postprocessing methodology suitable for their compensation and for assuring robust behavior.
Abstract
We review a true random number generator which internally exploits a pipeline analog-to-digital converter modified to operate in chaotic mode. Contrarily to other true random [...]
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Wounded rotor salient pole synchronous machine drive for the traction system of electric vehicles
D. Casadei, C. Rossi, L. Zarri, A. Pilati, A. Gaetani

Collection of closed conferences in transport research (2021). Vol. 2004, 6
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Quantitative Transport Risk Analysis on a Regional Scale: an application of TRAT-GIS to East Sicily
G. Spadoni, M. Milazzo, G. Maschio, G. Antonioni

Collection of closed conferences in transport research (2021). Vol. 2004, 5

Abstract
Sicily has a very high concentration of chemical plants, mainly petrochemical and refineries, and thus is an area with a great risk of industrial accidents; in addition to this there are several natural risk sources such as earthquakes, volcanic eruptions and land decay, as well as deficiencies in the infrastructure, such as the transport networks and facilities. Large petrochemical and refinery plants (Priolo, Gela and Milazzo) are located on the east side of the island in the vicinity of highly populated areas of great environmental, artistic and tourist importance. The quantity of oil and other chemical products which are processed in Sicily is about 50·106 t/yr. This causes an over-production compared to the regional needs, and therefore a large part of these substances is exported; thus the region is characterised by an inflow of raw materials and an outflow of final products. Unfortunately the transport infrastructure is inadequate to cope with such a high level of traffic; the rail network, for instance, is still mostly single track, while important parts of the highway network are incomplete. As a consequence there are urban areas subject to an intense traffic of hazardous materials and safety cannot be ensured. In this paper an extensive quantitative risk assessment applied to the land transport of dangerous goods through the a wide territory of Sicily is outlined. A complete inventory of dangerous substances, detailed in the paper, was the basis of a complete risk analysis. From both individual risk distribution and societal risk curves the importance of parameters has been obtained and this has suggested measures to reduce the risk in Sicily. Calculations will be done with the software code named TRAT (implemented on a GIS platform) which has been developed to evaluate the risk to human health and to the environment due to the transportation of dangerous goods. The case study focuses attention on the application of the analysis to a very large area which can be managed by TRAT-GIS without loss of accuracy in calculations compared to previous application of the code to more restricted areas, such as the crossing of the Straits of Messina. Looking at the fundamentals of the code, it has to be noted that the prediction of individual and societal risk measures can make use of some different wind vectors, each of them referring to a meteorological station and its surrounding district. Of course a discontinuity will arise on the border between two districts, but the results will still be more accurate rather than those obtained by considering the same wind vector over the whole area. This is especially true for toxic gases such as Chlorine and Ammonia (both transported in the region): for the first one, which is heavier than air, an important role is played, besides the direction of the wind, by the atmospheric stability class (e.g Pasquill class) too, while for Ammonia, lighter than air if ambient conditions are considered, the transport is mainly dominated by the wind velocity. To take account of all the atmospheric conditions, in terms of stability classes and wind direction and velocity, and of their distribution in the seasons and on the territory this new feature has been implemented in the software with the help of a GIS platform. The table shows the fluxes of the main kinds of hazardous substances transported by road and rail in Sicily. A large amount of vehicles carrying dangerous goods has to be managed in the region. The discussion on results involves a comparison between different means of transport, useful to establish an order of priority, and the comparison with different tolerability criteria in order to outline considerations based on the absolute measures of risk introduced. The transport of hazardous materials through Sicily is characterised by some critical areas. The crossing of the Straits of Messina represents a very critical situation. The critical point of the road transportati...
Abstract
Sicily has a very high concentration of chemical plants, mainly petrochemical and refineries, and thus is an area with a great risk of industrial accidents; in addition to [...]
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A course in air traffic control for developing countries development and implementation
G. Dimirovski

Collection of closed conferences in transport research (2021). Vol. 2003, 3

Abstract
This paper presents a working implementation of a course in Air Traffic Control (in the Rep. of Macedonia), which is believed to be properly tailored according to the needs of small developing countries that are likely to be users of this technology only. One version was designed for the undergraduate studies in Traffic Engineering at the Technical Faculty (TFB) in Bitola. The other version is designed for the graduate studies in Automation & Systems Engineering at Faculty of Electrical Engineering (FEE) in Skopje. While it may not be widely suitable for developing countries in general, it is believed these have largely met the objectives for such dedicated courses. Since, in all countries, some knowledge on air traffic control is indispensable in order to meet the internationally approved criteria, requirements and standards for proper world-wide air traffic operations. IEEE Aerosp & Elect Syst Soc; Aerosp Corp; Analog Interfaces; AstroExpo com; Caltech, JPL; Circle Mt Co; Gandalf Associates, LLC; GEB Software Technologies; Missile Defense Agcy; NASA; Panasonic; SpectrumAstro; Superior Solut; TechLink
Abstract
This paper presents a working implementation of a course in Air Traffic Control (in the Rep. of Macedonia), which is believed to be properly tailored according to the needs [...]
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Modelling traffic flows with intelligent cars and intelligent roads
C. Tampère, K. Malone, B. van Arem

Collection of closed conferences in transport research (2021). Vol. 2003, 2

Abstract
This paper addresses the modeling of traffic flows with intelligent cars and intelligent roads. It will describe the modeling approach MIXIC and review the results for different ADA systems: Adaptive Cruise Control, a special lane for Intelligent Vehicles, cooperative following and external speed assistance. In general there are clear indications for an improvement in traffic safety. It also shows that traffic efficiency impacts are limited and in specific conditions even negative. Given the increasing attention 10 more advanced driver assistance system, the paper proposes new research directions Assistance' and advanced modeling techniques toward 'integrated driver assistance'.
Abstract
This paper addresses the modeling of traffic flows with intelligent cars and intelligent roads. It will describe the modeling approach MIXIC and review the results for different [...]
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Provision of an emergency warning service through GPRS: Performance evaluation
R. Verdone, B. Masini, C. Fontana

Collection of closed conferences in transport research (2021). Vol. 2004, 3

Abstract
The investigation presented is focused on the methodologies to take advantage of the new communications technologies in vehicular traffic, improving security and efficiency. In this work, we show how to provide traffic and road information to users in vehicles coming up to dangerous situations through the use of the GPRS (general packet radio service) network and we analytically evaluate the probability to avoid the high risk zone for an equipped GPRS vehicle next to an accident. The results presented were obtained in the framework of the GITS (GPRS for intelligent transportation system) project, whose aim was to exploit the GPRS network to collect traffic information concerning the vehicles transiting in a covered area and to transmit traffic information to the drivers.
Abstract
The investigation presented is focused on the methodologies to take advantage of the new communications technologies in vehicular traffic, improving security and efficiency. [...]
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Modeling and evaluation of control flow prediction schemes using complete system simulation and Java workloads
R. Bell, T. Li, Z. John

Collection of open conferences in research transport (2003). Vol. 2003, 100

Abstract
Program control flow transfer (branch) prediction is considered to be a performance hurdle and a key design issue for current and future microprocessors. Branch prediction schemes with high prediction accuracy have been proposed to support longer processor pipelines with higher frequency clocks. In the previously published literature, the design and evaluation of branch predictors have been based heavily on the simulation of only user instructions from scientific and commercial workloads written in programming languages such as C or C++. To complement the existing research, the paper presents a case study of the modeling and evaluation of advanced branch predictors using full-system simulation of Java workloads running on a commercial operating system. The contributions of the paper are: (1) the presentation of a full system simulation framework to model, simulate and evaluate the performance of a set of advanced prediction schemes on emerging Java workloads; (2) an analysis of the performance and design complexity of advanced branch predictors in the presence of full system code; (3) an accurate modeling of user/kernel branch aliasing on a wide range of branch predictors.
Abstract
Program control flow transfer (branch) prediction is considered to be a performance hurdle and a key design issue for current and future microprocessors. Branch prediction [...]
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Time Shifting Air Traffic Data for Quantitative Evaluation of a Conflict Probe
R. Oaks, M. Paglione, J. Summerill, E. Township, W. Hughes

Collection of open conferences in research transport (2003). Vol. 2003, 99

Abstract
conflict probe is an air traffic management decision support tool that predicts aircraft-to-aircraft and aircraft-to-airspace conflicts. In order to achieve the confidence of the air traffic controllers who are provided this tool, a conflict probe must accurately predict these conflicts. This paper discusses how a conflict probe's quantitative accuracy requirements can be tested using hypothesis testing techniques. The paper also asserts that air traffic scenarios based on recorded field data are essential to the evaluation of a conflict probe and states that time shifting these scenarios can create data samples necessary to perform the hypothesis testing. This paper then compares three time shifting techniques: time compression, random time adjustment, and an implementation of a genetic algorithm.
Abstract
conflict probe is an air traffic management decision support tool that predicts aircraft-to-aircraft and aircraft-to-airspace conflicts. In order to achieve the confidence [...]
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High accuracy stereo vision system for far distance obstacle detection
R. Danescu, S. Nedevschi, F. Oniga, D. Frentiu, T. Graf, T. Marita, C. Pocol, R. Schmidt

Collection of open conferences in research transport (2004). Vol. 2004, 101

Abstract
This paper presents a high accuracy stereo vision system for obstacle detection and vehicle environment perception in a large variety of traffic scenarios, from highway to urban. The system detects obstacles of all types, even at high distance, outputting them as a list of cuboids having a position in 3D coordinates, size and speed.
Abstract
This paper presents a high accuracy stereo vision system for obstacle detection and vehicle environment perception in a large variety of traffic scenarios, from highway to [...]
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MPLS Multicast Traffic Engineering
A. Boudani, B. Cousin, J. Bonnin

Collection of open conferences in research transport (2003). Vol. 2003, 98

Abstract
International audience; In this paper, we present multicast traffic engineering and we compare it to unicast traffic engineering. We study the advantages given by the integration of multicasting and MPLS. We present current proposals for multicast traffic engineering and using MPLS network. We describe our approach, the MPLS multicast tree (MMT) protocol. In order to reduce forwarding states and enhance scalability, MMT utilizes MPLS LSPs between branching routers of the multicast tree. We present a simulator for MMT and finally we discuss some simulation results.
Abstract
International audience; In this paper, we present multicast traffic engineering and we compare it to unicast traffic engineering. We study the advantages given by the integration [...]
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Perception of VMS Effectiveness: A British and Canadian Perspective
J. Cheng, P. Firmin

Collection of open conferences in research transport (2004). Vol. 2004, 99

Abstract
Variable Message Signs are becoming a common sight on the UK Motorway network and have been well established on North American Freeways for several decades, as highway authorities strive to better manage scarce road network resources and provide travellers with up-to-date traffic information and alternative route options. The flexibility of VMS allows them to display varied information on road conditions, safety messages, alternate routes, speed limits, and general travel information. The steady growth in deployment of VMS in the next few years will lead to enhanced use of information to better manage highways and control levels of traffic congestion. The effectiveness of VMS in achieving this goal, however, depends entirely upon driver response to and perception of the information displayed.\\ud Previous research has indicated that VMS information needs to be timely, accurate, easily understandable and also believable for motorists to take any notice of it and act accordingly. This paper will report on findings from several attitudinal questionnaire surveys, conducted in and around London and Manchester in the UK, and Toronto in Canada, to determine VMS effectiveness. The studies focus on driver perception of the effectiveness of different types of information displayed and drivers’ preferences for future information provision.
Abstract
Variable Message Signs are becoming a common sight on the UK Motorway network and have been well established on North American Freeways for several decades, as highway authorities [...]
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Optimizing pipelines for power and performance
D. Brooks, M. Gschwind, P. Emma, P. Strenski, P. Bose, V. Zyuban, V. Srinivasan

Collection of open conferences in research transport (2003). Vol. 2003, 96

Abstract
During the concept phase and definition of next generation high-end processors, power and performance will need to be weighted appropriately to deliver competitive cost/performance. It is not enough to adopt a CPI-centric view alone in early-stage definition studies. One of the fundamental issues confronting the architect at this stage is the choice of pipeline depth and target frequency. In this paper we present an optimization methodology that starts with an analytical power-performance model to derive optimal pipeline depth for a superscalar processor. The results are validated and further refined using detailed simulation based analysis. As part of the power-modeling methodology, we have developed equations that model the variation of energy as a function of pipeline depth. Our results using a set of SPEC2000 applications show that when both power and performance are considered for optimization, the optimal clock period is around 18 FO4. We also provide a detailed sensitivity analysis of the optimal pipeline depth against key assumptions of these energy models.
Abstract
During the concept phase and definition of next generation high-end processors, power and performance will need to be weighted appropriately to deliver competitive cost/performance. [...]
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Introduction to the Visual Simulation Environment
C. Esterbrook, A. Bertelrud, R. Nance, O. Balci

Collection of open conferences in research transport (2003). Vol. 2003, 95
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Fast obstacle detection using flow/depth constraint
S. Heinrich

Collection of open conferences in research transport (2003). Vol. 2003, 94

Abstract
The early recognition of potentially harmful traffic situations is an important goal of vision based driver assistance systems. Pedestrians, in particular children, are highly endangered in inner city traffic. Within the DaimlerChrysler UTA (Urban Traffic Assistance) project, we are using stereo vision and motion analysis in order to manage those situations. The flow/depth constraint combines both methods in an elegant way and leads to a robust and powerful detection scheme.
Abstract
The early recognition of potentially harmful traffic situations is an important goal of vision based driver assistance systems. Pedestrians, in particular children, are highly [...]
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Formulation of a Method to Assess Capacity Enhancing Technologies
D. DeLaurentis, E. Garcia, D. Mavris

Collection of open conferences in research transport (2003). Vol. 2003, 93

Abstract
The demand for air travel is expanding beyond the capacity of existing airports and air traffic control. This excess traffic often results in delays and compromised safety. Therefore, a number of initiatives to improve airport capacity and throughput have been proposed. However, in order to assess the impact of these technologies on commercial air traffic one must move beyond the vehicle to a system-ofsystems point of view. This top-level perspective must include consideration of the aircraft, airports, air traffic management and airlines that make up the airspace system. In addition to the analysis of each of these components and their interactions, a thorough investigation of capacity and throughput technologies requires due consideration of other pressures such as economics, safety and government regulations. Furthermore, the air traffic system is inherently variable with constant changes in everything from fuel prices to the weather. Thus, the development of a modeling environment to be used in the evaluation of technological impacts while encompassing all these sources of uncertainty is the subject of this paper.
Abstract
The demand for air travel is expanding beyond the capacity of existing airports and air traffic control. This excess traffic often results in delays and compromised safety. [...]
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Policy-based network dimensioning for IP differentiated services networks
L. Georgiadis, P. Trimintzios, G. Pavlou, D. Griffin, P. Flegkas

Collection of open conferences in research transport (2003). Vol. 2003, 92

Abstract
Given the emergence of IP networks and the Internet as the multi-service network of the future, it is plausible to consider its use for transporting demanding traffic with high bandwidth and low delay and packet loss requirements. Emerging technologies for scalable quality of service such as differentiated services (DiffServ) and MPLS can be used for premium quality traffic. We look at the problem of intra-domain provisioning in an automated manner from the point of view of an Internet service provider (ISP), i.e. we want to satisfy the contracts with our customers while optimizing the use of network resources. We also need to be able to guide the behavior of such an automated provisioning system dynamically in order to be able to meet the high-level business objectives. The emerging policy-based management paradigm is the means to achieve this requirement. We devise first a nonlinear programming formulation of the traffic engineering problem and show that we can achieve the objectives and meet the requirements of demanding customer traffic through the means of an automated provisioning system. We extend the functionality of the automated system through policies. Finally, we present example scenarios of the enforcement of network dimensioning policies.
Abstract
Given the emergence of IP networks and the Internet as the multi-service network of the future, it is plausible to consider its use for transporting demanding traffic with [...]
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An application of parametric time series in simulation modeling
N. Polhemus, J. Hunter

Collection of open conferences in research transport (2003). Vol. 2003, 91

Abstract
parametric time series model is employed to simulate the number of aircraft present in an air traffic control sector. Borrowing from the work of Box and Jenkins, the identification, parameter estimation and associated tests of adequacy are illustrated using data from a low altitude control sector. The fitted model provides a useful algorithm and reflects the time dependency which exists between the number of aircraft measured in consecutive time periods. The simulation is part of a larger air communications system simulation which is under development.
Abstract
parametric time series model is employed to simulate the number of aircraft present in an air traffic control sector. Borrowing from the work of Box and Jenkins, the identification, [...]
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Driving the Phileas, a new automated public transport vehicle
D. de Waard, K. Brookhuis, E. Fabriek, P. Van Wolffelaar

Collection of open conferences in research transport (2004). Vol. 2004, 94

Abstract
Phileas is a high quality public transport vehicle combining characteristics of bus, tram, and the underground. Phileas is equipped with pneumatic tyres and complies with the statutory regulations for buses. Accordingly Phileas may drive everywhere on public roads where buses are allowed to drive. On dedicated lanes Phileas can also drive as a track vehicle and drive and stop automatically. This combination is new and as the dedicated lanes have level crossings with ordinary traffic this might have unexpected consequences in practice that must be studied in advance. For this reason 25 professional bus drivers have completed a number of experimental rides in a Phileas driving simulator. During these rides sometimes dangerous, and sometimes less dangerous, events happened that required active take-over of control by the driver. It was found that after the first experience with such a situation drivers always reclaimed control in time. It is advised to train the drivers on these situations, e.g. in a simulator, to avoid fatal consequences in real life first time encounters.
Abstract
Phileas is a high quality public transport vehicle combining characteristics of bus, tram, and the underground. Phileas is equipped with pneumatic tyres and complies with [...]
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Task allocation and automation in design and operation of man-machine systems
C. Arndt

Collection of open conferences in research transport (2003). Vol. 2003, 90

Abstract
The Structure of Intellect Capability-Requirement (SOI C-R) method has been found to be well suited to the evaluation of automation philosophies and new technologies. The SOI C-R method approach to function allocation and automation implementation is to fully describe the requirements of a task in a numeric representation and to represent the capabilities of task performance operators within the same numeric modeling space. The specific task requirements and capabilities of possible task operators can be compared numerically and an objective determination as to the best solution can be made. The first application of the SOI C-R method was the development of a domain suitability analysis tool for expert systems. This tool is the first comprehensive evaluation tool for determining whether a task should be allocated to expert systems. Also discussed is projected future research in this field.
Abstract
The Structure of Intellect Capability-Requirement (SOI C-R) method has been found to be well suited to the evaluation of automation philosophies and new technologies. The [...]
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High-speed non-linear asynchronous pipelines
P. Beerel, R. Ozdag, M. Singh, S. Nowick

Collection of open conferences in research transport (2003). Vol. 2003, 88

Abstract
Many approaches recently proposed for high-speed asynchronous pipelines are applicable only to linear datapaths. However, real systems typically have non-linearities in their datapaths, i.e. stages may have multiple inputs ('joins') or multiple outputs ('forks'). This paper presents several new pipeline templates that extend existing high-speed approaches for linear dynamic logic pipelines, by providing efficient control structures that can accommodate forks and joins. In addition, constructs for conditional computation are also introduced. Timing analysis and SPICE simulations show that the performance overhead of these extensions is fairly low (5% to 20%).
Abstract
Many approaches recently proposed for high-speed asynchronous pipelines are applicable only to linear datapaths. However, real systems typically have non-linearities in their [...]
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Energy minimization of system pipelines using multiple voltages
D. Kirovski, M. Srivastava, G. Qu, M. Potkonjak

Collection of open conferences in research transport (2003). Vol. 2003, 87

Abstract
Modem computer and communication system design has to consider the timing constraints imposed by communication and system pipelines, and minimize the energy consumption. We adopt the recent proposed model for communication pipeline latency and address the problem of how to minimize the power consumption in system-level pipelines under the latency constraints by selecting supply voltage for each pipeline stage using the variable voltage core-based system design methodology. We define the problem, solve it optimally under realistic assumptions and develop algorithms for power minimization of system pipeline designs based on our theoretical results. We apply this new approach to the 4-stage Myrinet GAM pipeline and with the appropriate voltage profiles, we achieve 93.4%, 91.3% and 26.9% power reduction on three pipeline stages over the traditional design.
Abstract
Modem computer and communication system design has to consider the timing constraints imposed by communication and system pipelines, and minimize the energy consumption. We [...]
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Generation of realistic air traffic scenarios using a genetic algorithm
M. Paglione, R. Oaks

Collection of open conferences in research transport (2003). Vol. 2003, 86

Abstract
Traffic flow management decision support tools such as the user request evaluation tool (URET), developed by the MITRE Center for Advanced Aviation Systems Development, and the Center-TRACON automation system (CTAS), developed by the NASA/Ames Research Center, use simulation as a tool for development, technical assessment, and field evaluation. Air traffic scenarios, based on recorded live data, are used to test these decision support tools. Frequently the scenarios need to be modified in order to create aircraft-to-aircraft encounters and conflicts that are not present in the live data. This paper presents an implementation of a genetic algorithm that is being used to time-shift the flights within an air traffic scenario to create encounters with specific constrained characteristics. These constraints are the distributions of the horizontal and vertical closest points of approach, the encounter angle at the closest point of horizontal approach, and the vertical type of encounter. This paper describes how the genetic algorithm was implemented, including a description of the solution chromosome and of the fitness function used to measure the potential solutions. After describing the implementation, a specific example of its use is presented.
Abstract
Traffic flow management decision support tools such as the user request evaluation tool (URET), developed by the MITRE Center for Advanced Aviation Systems Development, and [...]
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Decentralized local backup LSP calculation with efficient bandwidth sharing
L. Mélon, F. Blanchy, G. Leduc

Collection of open conferences in research transport (2003). Vol. 2003, 85

Abstract
This paper focuses on the protection of virtual circuits (Label Switched Paths, LSPs) in a (G)MPLS (Generalised Multi-Protocol Label Switching) network. The proposed algorithm is designed to protect traffic with strong delay requirements such as EF (Expedited Forwarding) ordered aggregates in a DiffServ domain. For this type of application endto- end recovery schemes are usually considered to be far too slow. Local, fast-rerouting is the only solution which can compete with restoration times offered by SONET self-healing ring. However local restoration has a cost in terms of extra bandwidth consumed for the backup paths. Our scheme thus includes a sophisticated resource aggregation mechanism based on the concepts of "backup-backup aggregation" and "backupprimary aggregation". The path selection algorithm is also designed to efficiently reduce the resource usage. Moreover, when considering LSPs at different preemption levels, our algorithm is able to correctly calculate the amount of bandwidth that can be preempted despite the sharing of resource. We show that our approach, though local, can compete with the state-of-theart end-to-end recovery schemes in terms of resource reservation. The major contribution of our scheme, the "backup-primary aggregation", was then also used in the context of end-to-end recovery and improved its performance substantially. Peer reviewed
Abstract
This paper focuses on the protection of virtual circuits (Label Switched Paths, LSPs) in a (G)MPLS (Generalised Multi-Protocol Label Switching) network. The proposed algorithm [...]
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Using expert systems to select software the traffic analysis
E. Chang

Collection of open conferences in research transport (2003). Vol. 2003, 84

Abstract
n expert system was developed by the Texas Transportation institute (TTI) to assist users in selecting computerized software currently being supported by the Federal Highway Administration (FHWA), U. S. Department of Transportation. This system was designed to investigate the potential expert systems applications in transportation engineering. This study was performed to serve three basic purposes. First, it investigates the feasibility of developing small-scale traffic engineering knowledge-based expert systems using a simple knowledge engineering tool. Secondly, it develops an alternative method of recommending computer programs for user-specified applications. Thirdly, it investigates a possible approach for implementing advisory expert systems to be operated in the IBM PC/XT/AT microcomputer environment. This paper describes the development of this expert system using a commercially available knowledge engineering tool developed by Level Five Research, Inc. INSIGHT 2+ was used to explore with the expert system programming in an inexpensive microcomputer environment. In operation, this system reviews and analyzes the user input information, evaluates with various reasoning paths and offers a conclusion. With the proper combination of knowledge programming tools and pre-identified decision-making processes, individual users can develop their applications faster than if they had to learn complex Artificial Intelligence programming languages. It is recommended that the expert advisory system design concept of this prototype model be extended to assist practicing traffic engineers in selecting software packages to optimize traffic control strategies. With proper improvement, this type of expert system design can assist the user as a stand-alone expert advice system.
Abstract
n expert system was developed by the Texas Transportation institute (TTI) to assist users in selecting computerized software currently being supported by the Federal Highway [...]
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Pricing, Capacity Choice and Financing in Transportation Networks
E. Verhoef, J. Rouwendal

Collection of open conferences in research transport (2003). Vol. 2003, 83

Abstract
This paper explores the interrelations between pricing, capacity choice and financingin transportation networks. It builds on the famous Mohring-Harwitz result on self-financing ofoptimally designed roads under optimal congestion pricing, and specifically investigates itsins and outs in a network environment and under various types of second-best regulation. Thepaper develops a small network model, with endogenous car-ownership, in order to study thesequestions both from an analytical and a numerical viewpoint. It is for instance shown thatapplication of the principle over an entire network may cause user prices to increase morestrongly in initially mildly congested areas compared to heavily congested areas, and that aflat kilometre charge, provided accompanied with optimal capacity policies, may result infirst-best efficiency gains.
Abstract
This paper explores the interrelations between pricing, capacity choice and financingin transportation networks. It builds on the famous Mohring-Harwitz result on self-financing [...]
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Principes de moindres action appropriés pour la modélisation des systèmes de distribution d'eau avec consommation fonction de la pression
B. Bremond, M. Poulton, O. Piller

Collection of open conferences in research transport (2003). Vol. 2003, 82

Abstract
Nowadays, the operation of a drinking water supply network can be assessed by using hydraulic computer models, such as "Porteau", developed by Cemagref. These models are accurate for high volume flows (such as emptying or filling of tanks) but less so for minimum flows. Partially closed valves, small diameter pipes and overestimation of consumption lead to difficult numerical problems. In these cases, optimization is required to prevent non-convergence of solutions. Besides, for such a model, consumption is an input and has to be estimated without considering the available pressure. Thus, demand overestimation is emphasized at the time of a network dysfunction, such as pipe breaks, pump failures and missing water resources. For about ten years, authors have proposed demand depending on available head. Such a model is known as a "Pressure Driven Model" (PDM), but theory and solving tools have not been fully developed yet.Firstly, two problems of optimization are associated to (PDM): one is written in terms of head loss and head, and the other in terms of flow rates. As with the classical models, they correspond to principles of least action. Next, equivalence of formulations and solution existence and uniqueness are demonstrated. Then, three descent algorithms of Newton type are proposed. Finally, the efficiency of these algorithms is proved in solving former problematic study cases.; De nos jours, le fonctionnement d'un réseau d'alimentation en eau potable peut être apprécié en utilisant un logiciel de calcul hydraulique, tel que " Porteau " développé par le Cemagref. Les résultats sont précis pour la prédiction des échanges de débits importants (tels que le remplissage ou la vidange d'un réservoir) ; ils le sont moins pour les petits débits. Des vannes partiellement fermées, des conduites de petits diamètres et la sur-estimation de la consommation conduisent à des problème numériques raides. Résoudre un problème d'optimisation par une méthode de descente empêche les situations de non-convergence. D'un autre côté, la consommation est fixée au préalable et doit être estimée sans tenir compte de la pression disponible. Ainsi, le problème de la sur-estimation de la demande est accentué lors d'un dysfonctionnement du réseau, tel qu'une casse de conduite, un non-fonctionnement de pompe ou un déficit de la ressource en eau. Depuis à peu près dix ans, les auteurs ont proposé des modèles avec consommation dépendant de la pression (PDM). Cependant, la théorie et les moyens de résolution n'ont pas été complètement développés jusqu'ici.Tout d'abord, deux problèmes d'optimisation sont associés aux PDM modèles : l'un est formulé dans l'espace des charges et des pertes de charges, et l'autre dans l'espace des débits. Comme pour les modèles classiques (avec demande ne dépendant pas la pression), ils correspondent à des principes de moindres actions. Ensuite, l'équivalence des formulations ainsi que l'existence te l'unicité sont démontrés. Alors, trois algorithmes de descente de type Newton sont proposés. Finalement, l'efficacité de ces algorithmes est prouvée en résolvant pour des cas d'école posant au préalable problème.
Abstract
Nowadays, the operation of a drinking water supply network can be assessed by using hydraulic computer models, such as "Porteau", developed by Cemagref. These models are accurate [...]
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A proposal for a radar system computer communication architecture
L. Bottino

Collection of open conferences in research transport (2003). Vol. 2003, 81

Abstract
The objective of this paper is to describe a computer communication architecture for an Air Space Management System (ASMS). This system is proposed for the Federal Aviation Administration William J. Hughes Technical Center (FAATC). Three transmission mediums will be used in the transfer and exchange of radar information. The methodology on computer/data communications and computer architecture will be discussed and analyzed. Geography, system topology and other system parameters have determined the computer network architecture best suited for the job. At the conclusion of this proposal a discussion of what would be accomplished by implementing this design, and lessons learned in researching this proposal will be presented.
Abstract
The objective of this paper is to describe a computer communication architecture for an Air Space Management System (ASMS). This system is proposed for the Federal Aviation [...]
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Comparison of Mitigation Alternatives for Water Distribution Pipelines Installed in Liquefiable Soils
W. Heubach, D. Ballantyne

Collection of open conferences in research transport (2003). Vol. 2003, 80

Abstract
Water pipeline distribution system mitigation measures are being evaluated: pipeline replacement, automated pipeline control systems, and planned manual valve actuation response. Seattle Public Utility’s distribution system is being used as model for this evaluation. The most vulnerable part of the distribution system is located in the highly liquefiable Duwamish River Valley. A decade ago, it was estimated that it would cost in excess of one billion dollars to replace all of the cast iron pipe founded in liquefiable soils in Seattle’s system. This cost was too expensive particularly when considering the other financial demands confronting the utility such as water treatment and reservoir upgrades. Seattle has joined forces with other water utilities in seismically active parts of the world to fund research under the American Water Works Association Research Foundation to evaluate alternate, less expensive, means of mitigating pipeline damage to improve the post-earthquake functionality of the system. The concern is that many pipelines will break, draining water from storage reservoirs, and also affect areas without significant pipeline damage. Following the Kobe earthquake, as well as many other earthquakes, this scenario has resulted in loss of water for fire suppression. Damage in the 2001 Nisqually Earthquake, as well as similar events in 1965 and 1949 was limited to less than 40 failures. However, a Cascadia subduction or Seattle Fault event will be much more damaging, and Seattle wants to be ready. The general strategy is to quickly isolate the damaged sections of the distribution network, or to replace pipe in the network so it will not fail. For each of these options, scenarios are being developed estimating pipeline performance and the resulting network hydraulic performance. The estimated costs and expected losses are being developed for a range of mitigation options. 1 Donald Ballantyne, Senior Consultant, MMI Engineering, Federal Way, WA. dballantyne@MMI Engineering.com 2 William Heubach, Formerly Senior Civil Engineer, Seattle Public Utilities, Current Bellevue, WA Utilities Departmen
Abstract
Water pipeline distribution system mitigation measures are being evaluated: pipeline replacement, automated pipeline control systems, and planned manual valve actuation response. [...]
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Characterization of network-wide anomalies in traffic flows
C. Diot, A. Lakhina, M. Crovella

Collection of open conferences in research transport (2004). Vol. 2004, 90

Abstract
Detecting and understanding anomalies in IP networks is an open and ill-defined problem. Toward this end, we have recently proposed the subspace method for anomaly diagnosis. In this paper we present the first large-scale exploration of the power of the subspace method when applied to flow traffic. An important aspect of this approach is that it fuses information from flow measurements taken throughout a network. We apply the subspace method to three different types of sampled flow traffic in a large academic network: multivariate timeseries of byte counts, packet counts, and IP-flow counts. We show that each traffic type brings into focus a different set of anomalies via the subspace method. We illustrate and classify the set of anomalies detected. We find that almost all of the anomalies detected represent events of interest to network operators. Furthermore, the anomalies span a remarkably wide spectrum of event types, including denial of service attacks (single-source and distributed), flash crowds, port scanning, downstream traffic engineering, high-rate flows, worm propagation, and network outage.
Abstract
Detecting and understanding anomalies in IP networks is an open and ill-defined problem. Toward this end, we have recently proposed the subspace method for anomaly diagnosis. [...]
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Adaptive pipeline structures for speculation control
A. Efthymiou, J. Garside

Collection of open conferences in research transport (2003). Vol. 2003, 79

Abstract
Pipelining is a common method for improving the throughput of a system, especially when the majority of the processing is sequential. Unfortunately when the sequentiality is broken, a pipelined system suffers additional delay and, most importantly for this work, energy waste which is roughly proportional to the pipeline depth. Standard pipelines cannot be modified once they are built so their depth is fixed. This paper proposes a method that allows the dynamic adaptation of the structure of an asynchronous pipeline, so that pipeline stages can be merged and split at run-time, allowing greater flexibility. It is based on novel latch controllers that can be configured dynamically as 'normal' or 'collapsed', i.e. keeping their latches permanently transparent. Using these controllers a model of AMULET3 was designed that is capable of changing its pipeline depth dynamically when branches are anticipated, in order to alleviate the energy loss when the branch finally arrives.
Abstract
Pipelining is a common method for improving the throughput of a system, especially when the majority of the processing is sequential. Unfortunately when the sequentiality [...]
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MIST---a design aid for programmable pipelined processors
A. Casavant

Collection of open conferences in research transport (2003). Vol. 2003, 77

Abstract
In this paper, a tool to aid pipelined processor instruction set implementation is described. The purpose of the tool is to choose from among design alternatives a design that minimizes overall processor cost. In the proposed cost model processor cost has two components, the cost of hardware necessary to realize the processor and the cost of degraded performance due to pipeline hazards as compared to an ideal pipelined processor. The tool user provides several alternate hardware implementations of each instruction, the cost of hardware operators used, a trade-off factor representing the relative importance of hardware cost versus degraded performance cost, and a straight line benchmark program which is used by the tool to determine frequency of occurrence of pairs of instructions. Using a linear programming approach, the tool selects an implementation for each instruction which gives an overall cost which is optimal.
Abstract
In this paper, a tool to aid pipelined processor instruction set implementation is described. The purpose of the tool is to choose from among design alternatives a design [...]
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Interdomain traffic engineering with redistribution communities
B. Quoitin, S. Uhlig, S. Tandel, O. Bonaventure, A. Services

Collection of open conferences in research transport (2004). Vol. 2004, 86

Abstract
Various traffic engineering techniques are used to control the flow of IP packets inside large ISP networks. However, few techniques have been proposed to control the flow of packets between domains. In this paper, we focus on the needs of stub ISPs that compose 80% of the global Internet. We first describe the typical traffic pattern of such a stub ISP. Then we briefly describe the methods that those ISPs currently use to engineer their interdomain traffic. We focus on the control of the incoming traffic and show the increasing utilization of the BGP Community attribute and discuss the limitations of this approach. We then propose the redistribution communities as a deployable method to control the flow of the incoming interdomain traffic. We implement those redistribution communities in zebra and evaluate its performance. (C) 2003 Elsevier B.V. All rights reserved.
Abstract
Various traffic engineering techniques are used to control the flow of IP packets inside large ISP networks. However, few techniques have been proposed to control the flow [...]
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Genetic algorithms applied to airport ground traffic optimization
J. Gotteland, N. Durand

Collection of open conferences in research transport (2003). Vol. 2003, 76

Abstract
Due to air traffic growth and especially hubs development, major European airports can easily become bottlenecks in the global air transportation network. Therefore, accurate models of airport traffic prediction become more and more necessary for ground controllers. In this paper, a ground traffic simulation tool is proposed and applied to Roissy Charles De Gaulle airport. Two global optimization methods, using genetic algorithms at the airport, are developed to minimize taxiing time while respecting aircraft separation and runway capacities. In order to compare the efficiency of the different methods, simulations are carried out on a one day traffic sample, and ground delay is correlated to the traffic density at the airport.
Abstract
Due to air traffic growth and especially hubs development, major European airports can easily become bottlenecks in the global air transportation network. Therefore, accurate [...]
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In-vehicle ambient intelligent transport systems (I-VAITS): Towards an integrated research
R. Tay, A. Rakotonirainy

Collection of open conferences in research transport (2004). Vol. 2004, 84

Abstract
The ever increasing use of ICT (information communication technology) in cars to improve the mobility, comfort and safety has sparkled the interests of the ambient intelligent research community. It is widely accepted that the use of advanced in-vehicle technology could contribute to a driver's distraction. Information overload or inappropriateness of the methods and time to convey information to the driver are among the potential drawbacks of the use of in-vehicle technology. This paper identifies the future research directions on driving assistance interactions design. It focuses on factors that preserve or enhance the driver's ability to drive and presents an in-vehicle ambient intelligent transport (I-VAITS) architecture.
Abstract
The ever increasing use of ICT (information communication technology) in cars to improve the mobility, comfort and safety has sparkled the interests of the ambient intelligent [...]
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A simulation study to investigate runway capacity using TAAM
M. Bazargan, P. Subramanian, K. Fleming

Collection of open conferences in research transport (2003). Vol. 2003, 75

Abstract
This study outlines a method to evaluate runway layouts using simulation, to aid in the airport planning and decision making process. As a sample study, the maximum throughput capacities of proposed expansion alternatives at Philadelphia International Airport (PHL), constrained at varying levels, are identified. The objective is to compare these ultimate airport capacities achievable for each of the different layouts to estimate their respective efficiencies in terms of runway system utilization. TAAM (Total Airspace and Airport Modeller) is used to simulate each proposed alternative given its capabilities for modeling at a very high level of detail and closely representing reality in terms of applicable separation standards and air traffic control procedures.
Abstract
This study outlines a method to evaluate runway layouts using simulation, to aid in the airport planning and decision making process. As a sample study, the maximum throughput [...]
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Development of Conflict-Free, Unrestricted Climbs for a Terminal Area Departure Tool
D. Isaacson, Y. Jung

Collection of open conferences in research transport (2003). Vol. 2003, 74

Abstract
The Expedite Departure Path (EDP) is a decision support tool being developed at NASA Ames Research Center aimed at providing Terminal Area Radar Approach Control (TRACON) Traffic Management Coordinators (TMCs) with pertinent departure traffic loading and scheduling information and radar controllers with advisories for tac tical control of terminal area departure traffic. One of the proposed features of EDP is to provide departure controllers with the ability to perform unrestricted climbs where procedures typically restrict departures below incoming arrival traffic streams . The potential benefits of this feature include reductions in time -to -climb, fuel burn, and aircraft noise impact to the surrounding communities. This paper focuses on the issue of unrestricted climb in congested terminal areas and describes the modeli ng and simulation of such climbs. First, flight data of departures in TRACON airspace were analyzed to estimate the level of uncertainties in climb trajectory prediction. Second, the existing Trajectory Synthesizer (TS) module of the Center -TRACON Automa tion System (CTAS) was modified to generate trajectories that closely model actual aircraft climb profiles and terminal airspace procedures. Third, an algorithm was applied to predict conflicts between trajectories of departure and arrival aircraft and to determine if an unrestricted climb is advisable. Controller -in -the loop simulations were performed to validate the feasibility of the algorithm and evaluate human factors. Lastly, a future application of a conflict probability estimation method for EDP was examined.
Abstract
The Expedite Departure Path (EDP) is a decision support tool being developed at NASA Ames Research Center aimed at providing Terminal Area Radar Approach Control (TRACON) [...]
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Multi-Agent Simulation of Human Behavior in Naval Air Defense
S. Calfee, N. Rowe

Collection of open conferences in research transport (2004). Vol. 2004, 82

Abstract
This paper appeared in the Naval Engineers' Journal, 116 (4), Fall 2004, 53-64. The AEGIS Cruiser Air-Defense Simulation is a program that models the operations of a Combat Information Center team performing air defense for a U.S. Navy battle group. It uses multi-agent system technology and is implemented in Java. Conceived primarily to assist personnel in air-defense training and doctrine formulation, the simulation provides insight into the factors (skills, experience, fatigue, aircraft numbers, weather, etc.) that influence performance, especially under intense or stressful situations, and the task bottlenecks. It simulates air contacts (aircraft and missiles) as well as the actions and mental processes of the watchstanders. All simulated events are logged, to permit performance analysis and reconstruction for post-scenario training. Validation of the simulation was done with the help of expert practitioners of air defense at the AEGIS Training & Readiness Center (ATRC), San Diego, California, USA. Approved for public release; distribution is unlimited.
Abstract
This paper appeared in the Naval Engineers' Journal, 116 (4), Fall 2004, 53-64. The AEGIS Cruiser Air-Defense Simulation is a program that models the operations of a Combat [...]
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Expert system to calculate the cofficient of friction : an approach to enhance traffic safety
Y. Siril, K. Askar, M. Dougherty

Collection of open conferences in research transport (2004). Vol. 2004, 81

Abstract
Friction plays a key role in causing slipperiness as a low coefficient of friction on the road may result in slippery and hazardous conditions. Analyzing the strong relation between friction and accident risk on winter roads is a difficult task. Many weather forecasting organizations use a variety of standard and bespoke methods to predict the coefficient of friction on roads. This article proposes an approach to predict the extent of slipperiness by building and testing an expert system. It estimates the coefficient of friction on winter roads in the province of Dalarna, Sweden using the prevailing weather conditions as a basis. Weather data from the road weather information system, Sweden (RWIS) was used. The focus of the project was to use the expert system as a part of a major project in VITSA, within the domain of intelligent transport system
Abstract
Friction plays a key role in causing slipperiness as a low coefficient of friction on the road may result in slippery and hazardous conditions. Analyzing the strong relation [...]
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Routing in a MPLS network featuring preemption mechanisms
F. Blanchy, L. Mélon, G. Leduc

Collection of open conferences in research transport (2003). Vol. 2003, 73

Abstract
In the context of multiprotocol label switching (MPLS), we propose an integration of a computationally efficient preemption mechanism into a very dynamic label switched paths (LSPs) routing scheme we described previously (Blanchy et al., http://run.montefiore.ulg.ac.be//spl sim/blanchy, 2002). This preemption scheme includes a quick heuristic able to select the most interesting LSPs to reroute from a link. The efficiency of this algorithm is obtained through a very rigid, but seemingly appropriate, policy which is concerned which LSPs are appropriate for preemption. A feedback from preemption on the routing process is proposed, in order to regulate the rate of rerouting and to tune the balance between stability and continuous reorganization in a network. This integrated traffic engineering entity is tested on the accuracy of the heuristic, the relevance of the feedback and the whole integration, the influence of the routing policy on the preemption mechanism and the reliability of the managed network.
Abstract
In the context of multiprotocol label switching (MPLS), we propose an integration of a computationally efficient preemption mechanism into a very dynamic label switched paths [...]
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Randomized algorithms for probabilistic aircraft conflict detection
S. Sastry, M. Prandini, J. Lygeros, A. Nilim

Collection of open conferences in research transport (2003). Vol. 2003, 72

Abstract
mid-range conflict alerting system is proposed, based on a measure of criticality which directly takes into account the uncertainty in the prediction of the aircraft positions. The use of randomized algorithms makes the computation of the criticality measure tractable. The performance of the algorithm is evaluated by Monte Carlo simulation on a stochastic ODE model of the aircraft motion.
Abstract
mid-range conflict alerting system is proposed, based on a measure of criticality which directly takes into account the uncertainty in the prediction of the aircraft positions. [...]
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Assessing the Effects of Vibratory Loading on Pipelines Using Analysis and Monitoring Techniques
D. Runte, R. Long, C. Alexander

Collection of open conferences in research transport (2004). Vol. 2004, 76

Abstract
This paper provides the methods and results associated with an engineering assessment for a project involving pile driving adjacent to an active 6-inch (152 mm) nominal diameter gas pipeline. The pile driving was associated with the expansion of the I-95 Highway located in Daytona Beach, Florida. The work involved analysis, metallurgical field evaluation, and measurement of strain and acceleration in the pipe during the pile driving. The analysis involved using finite element methods to predict stresses in the pipe using acceleration loads provided during a previous pile driving exercise. Using a range of soil stiffness values, the calculated bending stresses in the pipeline ranged from 50 to 2,000 psi (0.3 to 13.8 MPa). Even with the most compliant soils, the stress was relatively low compared to the hoop stress created by an internal pressure of 500 psi (3.4 MPa). The metallurgical field investigation involved careful inspection of the pipe quality, including field replication and determining the carbon content of one weld. The strain measurements indicated that the stress levels in the pipe were below design stress limits and that the short-term pile driving loads did not inflict serious injury to the line. Findings of the investigation indicated that the pipe had been well-maintained over its 40 year life and that no measurable corrosion was present. This project demonstrates the benefits derived in using a range of engineering disciplines and capabilities to ensure safety in conducting potentially-damaging activities adjacent to active gas pipelines.Copyright © 2004 by ASME
Abstract
This paper provides the methods and results associated with an engineering assessment for a project involving pile driving adjacent to an active 6-inch (152 mm) nominal diameter [...]
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Controller acceptance of new air traffic control (ATC) automation
E. Meyer

Collection of open conferences in research transport (2003). Vol. 2003, 70

Abstract
With rapid growth in air traffic, the Federal Aviation Administration (FAA) has been under considerable pressure to increase the capacity of the National Airspace System. One of the FAA's solutions is to provide air traffic controllers with automation tools designed to increase their efficiency. Using experience with the Free Flight Program as a case study, this paper explores some of the challenges and successes with implementing new air traffic control automation tools.
Abstract
With rapid growth in air traffic, the Federal Aviation Administration (FAA) has been under considerable pressure to increase the capacity of the National Airspace System. [...]
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Structural analysis of network traffic flows
N. Taft, A. Lakhina, M. Crovella, K. Papagiannaki, E. Kolaczyk, C. Diot

Collection of open conferences in research transport (2004). Vol. 2004, 73

Abstract
Network traffic arises from the superposition of Origin-Destination (OD) flows. Hence, a thorough understanding of OD flows is essential for modeling network traffic, and for addressing a wide variety of problems including traffic engineering, traffic matrix estimation, capacity planning, forecasting and anomaly detection. However, to date, OD flows have not been closely studied, and there is very little known about their properties.We present the first analysis of complete sets of OD flow time-series, taken from two different backbone networks (Abilene and Sprint-Europe). Using Principal Component Analysis (PCA), we find that the set of OD flows has small intrinsic dimension. In fact, even in a network with over a hundred OD flows, these flows can be accurately modeled in time using a small number (10 or less) of independent components or dimensions.We also show how to use PCA to systematically decompose the structure of OD flow timeseries into three main constituents: common periodic trends, short-lived bursts, and noise. We provide insight into how the various constitutents contribute to the overall structure of OD flows and explore the extent to which this decomposition varies over time.
Abstract
Network traffic arises from the superposition of Origin-Destination (OD) flows. Hence, a thorough understanding of OD flows is essential for modeling network traffic, and [...]
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Air traffic management for commercial and military systems integrating human factors in air traffic control research and acquisition
J. Rehmann, P. Krois

Collection of open conferences in research transport (2003). Vol. 2003, 68

Abstract
The Federal Aviation Administration (FAA) and the National Astronautics and Space Administration (NASA) have partnered their research efforts through the Interagency Air Traffic Management Integrated Product Team (IAIPT). The IAIPT's mission is to integrate research addressing air traffic control (ATC) and air traffic management (ATM) decision support tools, concepts, and procedures. As a crosscutting area, integrating human factors research intends to systematically identify and coordinate research and acquisition efforts in developing and assessing advanced ATM and communication, navigation and surveillance (CNS) capabilities relative to human performance limitations and capabilities.
Abstract
The Federal Aviation Administration (FAA) and the National Astronautics and Space Administration (NASA) have partnered their research efforts through the Interagency Air Traffic [...]
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Explorer: Untethered Real-Time Gas Main Assessment Robot System
G. Vradis, H. Schempf

Collection of open conferences in research transport (2003). Vol. 2003, 67

Abstract
With funding from the NorthEast Gas Association (NGA), the U.S. Department of Energy (DoE) and NASA, Carnegie Mellon University (CMU) has developed Explorer, a long range, un-tethered, modular inspection robot for the visual inspection of 6” and 8” natural gas distribution system pipelines. The robot can be launched into the pipeline under live conditions utilizing a commercial no-blow system via a specially designed attachment, and can negotiate diameter changes, 45-deg and 90-deg bends and tees, as well as inclined and vertical pieces of the piping network. The modular design of the system allows it to be expanded in the near future to include additional inspection and/or repair tools. The range of the robot is an order of magnitude higher than present state-of-the-art inspection systems and is expected to fundamentally alter the way gas utilities maintain and manage their systems. A prototype system has been built, and is undergoing extensive laboratory system testing prior to scheduled field demonstrations, expected for the summer and fall of 2003. This paper will describe the overall engineering design and functionality of the design, as well as present preliminary laboratory testing demonstration (a video of the system in operation will be shown at the conference).
Abstract
With funding from the NorthEast Gas Association (NGA), the U.S. Department of Energy (DoE) and NASA, Carnegie Mellon University (CMU) has developed Explorer, a long range, [...]
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A stated preference survey for investigating route choice behaviour in Adelaide
Collection of open conferences in research transport (2004). Vol. 2004, 66

Abstract
2004
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A systems approach to the design of data cycle maps for the flight-testing of air vehicles
Collection of open conferences in research transport (2004). Vol. 2004, 64

Abstract
2004
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Satellite imagery for volcanic hazards mitigation
G. Wadge, G. Ellrod, R. Helz

Collection of open conferences in research transport (2003). Vol. 2003, 65

Abstract
world population and urbanization increase, volcanoes pose an ever greater hazard to life, property, and infrastructure in volcanically active regions. The rise in air traffic world-wide increases the risk of encounters between airborne ash and aircraft, even at great distances from the source. The Committee on Earth Observation Satellites (CEOS), an international association of civilian space agencies, seeks to foster cooperation to increase the usefulness and accessibility of satellite imagery. In February 1997, CEOs initiated the Disaster Management Support Project to assess the present and potential use of satellite-derived information for the mitigation of several hazards, including volcanic hazards. Radar methods are discussed.
Abstract
world population and urbanization increase, volcanoes pose an ever greater hazard to life, property, and infrastructure in volcanically active regions. The rise in air traffic [...]
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A Feedback Linearizing Controller for Relative Guidance Between Commercial Aircraft
F. Mora-Camino, K. Achaibou, T. Miquel

Collection of open conferences in research transport (2003). Vol. 2003, 64

Abstract
International audience; During the last few years, several concepts concerning the delegation to commercial aircraft flight crew of some tasks currently performed by the air traffic controllers have emerged [3]. Among these new ideas, relative guidance has appeared to be of some interest to contribute to the enhancement of air traffic capacity [1] though it rises hard technical challenges. Indeed, this kind of maneuver appears difficult to perform manually, and may induce an excessive increase of the flight crew workload, thus requiring a new on-board automated function, as suggested in [7]. This paper investigates the design of an autopilot mode dedicated to the trailing aircraft for merging and maintaining station keeping behind a leading aircraft. The investigated approach is based on feedback linearization control. We use a new form of relative position error which results in a singularity free stabilizing controller. Moreover, we take explicitly into account the separation between the two aircraft in order to safely manage the maneuver. Some properties of such a controller are also discussed on the basis of a case study including wind.
Abstract
International audience; During the last few years, several concepts concerning the delegation to commercial aircraft flight crew of some tasks currently performed by the air [...]
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Topological design of multiple VPNs over MPLS network
D. Tipper, A. Srikitja

Collection of open conferences in research transport (2003). Vol. 2003, 63

Abstract
With the deployment of MPLS over a core IP backbone, it is possible for a service provider to built Virtual Private Networks (VPNs) supporting various classes of services with QoS guarantees. Efficiently mapping the logical layout of multiple VPNs over a service provider network is an important and challenging traffic engineering procedure. The use of sink-tree (multipoint-to-point) routing paths in a MPLS network makes the VPN design problem different from traditional design approaches where a full-mesh of point-to-point paths is often the choice. The clear benefits of using sink-tree paths are the reduction in the number of label switch paths and bandwidth saving due to larger granularities of bandwidth aggregation within the network. In this paper, the design of multiple VPNs over MPLS, using sink-tree routing, is formulated as a mixed integer programming problem to simultaneously find VPNs logical topologies and their dimensions to carry multi-service, multi-hour VPNs traffic from various customers. Such a problem formulation yields an NP-hard complexity. Here, we propose a heuristic aiming to scale the VPN design problem by choosing a small-but-good candidate set of feasible sink-tree paths to solve the optimization problem over. Numerical results are given showing the advantages of the proposed approach.
Abstract
With the deployment of MPLS over a core IP backbone, it is possible for a service provider to built Virtual Private Networks (VPNs) supporting various classes of services [...]
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Special Phased Array Applications for Pipeline Girth Weld Inspections
N. Dube´, S. Labbe, M. Moles

Collection of open conferences in research transport (2004). Vol. 2004, 62

Abstract
Ultrasonic phased arrays present major improvements over conventional multiprobe ultrasonics for inspecting pipeline girth welds, both for onshore and for offshore use. Probe pans are lighter and smaller, permitting less cutback; scans are quicker due to the smaller probe pan; phased arrays are considerably more flexible for changes in pipe dimensions or weld profiles, and for different scan patterns. More important, some of the potential advantages of phased arrays are now becoming commercially available. These include: compensating for variations in seamless pipe wall thickness; wedge temperature compensation; premium inspections for risers, tendons and other components; small diameter pipes; multiple displays; clad pipe; portable phased arrays for tie-ins and repairs; improved sizing approaches. The paper will describe the latest phased array UT results for special applications.Copyright © 2004 by ASME
Abstract
Ultrasonic phased arrays present major improvements over conventional multiprobe ultrasonics for inspecting pipeline girth welds, both for onshore and for offshore use. Probe [...]
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Aircraft conflict prediction and resolution using Brownian motion
M. Prandini, J. Lygeros, S. Sastry, J. Hu

Collection of open conferences in research transport (2003). Vol. 2003, 62

Abstract
The probability of conflict between two aircraft is calculated by modeling aircraft motion as a deterministic trajectory plus a (scaled) Brownian motion perturbation. In this formalism, the probability of conflict becomes the probability that a Brownian motion escapes from a time-varying safe region. Approximate expressions for the probability of conflict are obtained in closed form for both the finite and infinite horizon cases. Based on these expressions, an autonomous algorithm is proposed for decentralized conflict resolution. The algorithm generalizes potential field ideas to path planning in a highly dynamic environment.
Abstract
The probability of conflict between two aircraft is calculated by modeling aircraft motion as a deterministic trajectory plus a (scaled) Brownian motion perturbation. In this [...]
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A Unique Pipeline Fault Crossing Design for a Highly Focused Fault
N. Zulfiqar, J. Hart, F. Dauby, C. Hitchcock, K. Kelson, C. Lee

Collection of open conferences in research transport (2004). Vol. 2004, 60

Abstract
This paper describes the development of a unique pipeline fault crossing design upgrade for a 22-inch (559 mm) diameter Pacific Gas & Electric Company (PG&E) gas transmission line where it crosses the Calaveras fault near Sunol, California. The new design is capable of withstanding significant levels of horizontal fault offset while minimizing the deformation demands experienced by the pipeline. This unique design concept is applicable to fault crossings with well defined fault locations and highly localized fault offset profiles (e.g., for this fault, 85% of the offset is expected to occur within ±5 feet (±1.5 m) from the center of the fault trace, which was precisely located by field trenching studies). Relative to the original fault crossing design, the new design provides a more favorable “local” fault crossing angle “β” (β = 73° for the original design vs. β = 95° for the new design). The angle change is accomplished by installing an offset section of the pipeline adjacent to the fault such that the fault crosses the pipeline in the middle of a tangent section in the nearest offsetting leg. The four bends used to fabricate the offset section are cold bends with an average radius of 76.4 feet (23.3 m). The entire mitigated section of the pipeline is buried in a select sand trench. For this design configuration, right lateral fault motion results in (a) a “closing” action within the two adjacent cold bends located on either side of the fault and (b) a net tension force in the pipe (due to the obtuse β value) centered on the tangent section of the offsetting leg containing the fault crossing. The net tension force in the offsetting leg results in an “opening” action within the two adjacent cold bends on either side of the fault. By adjusting the local fault crossing angle β, the “bend opening” action that results from pipe extension across the fault can be made to nearly offset the “bend closing” action induced by the transverse component of the fault offset. The use of a select sand backfill in the retrofit section allows the bends to engage the soil with relatively low transverse and longitudinal resistance thereby enhancing the overall flexibility/compliance of the fault crossing design. Implementation of this unique design concept at the Calaveras fault crossing increased the amount of fault offset required to damage the pipeline from about 7 inches (18 cm) for the “as-built” design to well over 90 inches (2.3 m) for the retrofit.
Abstract
This paper describes the development of a unique pipeline fault crossing design upgrade for a 22-inch (559 mm) diameter Pacific Gas & Electric Company (PG&E) gas transmission [...]
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Framework for synthesis of virtual pipelines
S. Dasasathyan, R. Vemuri, R. Radhakrishnan

Collection of open conferences in research transport (2003). Vol. 2003, 60

Abstract
Virtual Pipelining allows designs of arbitrary size to execute on finite sized FPGA devices. It allows pipelined designs to be efficiently configured on a FPGA by overlapping the reconfiguration time of a pipeline stage with the execution time of previous pipeline stages. This technique produces performance improvement up to an order of 5 versus a non-pipelined execution of a design. We extend this principle for handling large designs that were previously too large to fit on an FPGA. This paper presents a framework for automatically synthesizing virtual pipelines on an Virtex FPGA. We also suggest criteria for extending our approach to non-Virtex FPGAs.
Abstract
Virtual Pipelining allows designs of arbitrary size to execute on finite sized FPGA devices. It allows pipelined designs to be efficiently configured on a FPGA by overlapping [...]
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A miniature inspection robot negotiating pipes of widely varying diameter
K. Suzumori, S. Wakimoto, M. Takata

Collection of open conferences in research transport (2003). Vol. 2003, 59

Abstract
The purpose of this research is to realize a small robot which can negotiate pipes whose diameter varies widely during the robot's course. A new in-pipe locomotion mechanism named "snaking drive" is proposed in this paper and its potential and fundamental characteristics are shown with experimental data of the prototype model. First, in the sections 2 to 5, the basic traveling characteristics of the snaking drive mechanism are discussed: a theoretical formula of the fundamental characteristics and control algorithm are derived, the motions of the robot are simulated on a PC, and the prototype model was designed, developed, and tested. Next, in the sections 6 and 7, additional control algorithms for the front link are derived. They are necessary for steering at T-branches and L-bends of pipes, and also for camera view stabilization. Their performances are also shown by software simulation and experiments. The prototype robots moved in pipes whose diameter varies between 55 mm to 331 mm with the maximum speed of 22 mm/s. The paper also shows that the prototype negotiates T-branches and L-bends of pipes with inspection capability through a camera mounted on the robot.
Abstract
The purpose of this research is to realize a small robot which can negotiate pipes whose diameter varies widely during the robot's course. A new in-pipe locomotion mechanism [...]
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Development of the future aeronautical subnetworks traffic evaluator (FASTE) for CNS systems
C. Wargo, D. Robinson, S. Mainger

Collection of open conferences in research transport (2003). Vol. 2003, 57

Abstract
The FASTE-CNS project is the first phase of a software-based set of tools to assist in the complex task of estimating and modeling aeronautical traffic for future operational environments; including general aviation, business aviation and commercial air transport. Traffic estimating involves two major activities: determination of transactional loads and determination of aircraft densities for the region of interest. Transactional analysis involves understanding the applications using aeronautical communications. Examples of these applications include owner operational control, weather, air traffic control, surveillance, navigation and passenger related activities. The services supported by these applications cause air-to-ground communication transactions to occur throughout the duration of the flight. This creates traffic loads on the communication media systems that are used to form the communications channels of the aeronautical subnetwork. These media channels are often shared mechanisms, and thus, the aircraft density within a given airspace region is the other important factor in performing communication traffic forecasts. FASTE-CNS provides a web-based means for the system engineering community to collaborate on producing traffic forecasts. The system provides a means to model the resource use of the media channels. This collaboration yields benefits in providing a shared understanding of system resource use and reduces the cost of recurring traffic forecast analysis.
Abstract
The FASTE-CNS project is the first phase of a software-based set of tools to assist in the complex task of estimating and modeling aeronautical traffic for future operational [...]
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A Route-Oriented Simulation System for ATC studies
E. Thomas, W. Sutherland, D. Henderson, T. Myer

Collection of open conferences in research transport (2003). Vol. 2003, 55

Abstract
simulation system for modeling air traffic situations is described. Real- or fast-time control of many aircraft over easily defined routes is provided. Simulated aircraft can be vectored manually or instructed to follow routes predefined by the experimenter. Special language forms have been developed for describing both the geographical and procedural aspects of these routes. The program runs in a PDP-10 timeshared computer and capitalizes on some of the standard system features. The influence of the interactive computer environment on the program's development and operation is discussed.
Abstract
simulation system for modeling air traffic situations is described. Real- or fast-time control of many aircraft over easily defined routes is provided. Simulated aircraft [...]
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Electromagnetic Surface Method for the Pipeline Periodical Inspection Based on the Heterogeneous Transmission Line Model
V. Shevnin, E. Nakamura, A. Mousatov

Collection of open conferences in research transport (2004). Vol. 2004, 55

Abstract
The superficial electromagnetic methods are widely applied for non-destructive control of pipeline technical condition. For this purpose we have developed the theory and field technology for the pipeline inspection that allows: 1) determining the pipeline trajectory (plane position and depth), 2) delimitation of pipeline intervals with an insulation coating damage, and 3) estimating the condition of a cathodic protection system. The proposed method is based on the approximation of a metallic pipeline by a heterogeneous transmission line with variable distributed parameters: resistance and inductance along a tube (tube wall thickness) and leakage conductance. The field operations consist in measurements of magnetic field above a pipeline and voltage only on the control posts. The interpretation process includes the iterative inversion of the magnetic component in order to determine the pipeline depth and current distribution along pipeline. The current difference corresponds to leakage current and allow estimate the leakage resistance. We illustrate the practical application of this method using the obtained results for pipeline inspections in Mexico. Based on the voltage and current simulations for the infralow-frequency band (0–1kHz) we have evaluated the feasibility of the time lapse measurements of the magnetic field in some fixed points for the early prediction of an insulation damaging process.
Abstract
The superficial electromagnetic methods are widely applied for non-destructive control of pipeline technical condition. For this purpose we have developed the theory and field [...]
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Gas pipeline monitoring in Europe by satellite SAR
A. Smith

Collection of open conferences in research transport (2003). Vol. 2003, 54

Abstract
present, gas pipeline networks in Europe are routinely monitored by vehicle and air patrols to protect them against damage by soil movement and third part interference. Because of the expenses, pipeline operators are investigating the possibilities to replace these traditional monitoring methods by remote sensing from space. A preliminary analysis shows that considerable savings can be achieved by deploying a user network of ground stations to receive the Synthetic Aperture Radar (SAR) data of the ENVISAT, RADARSAT-2. ALOS and TerraSAR satellite
Abstract
present, gas pipeline networks in Europe are routinely monitored by vehicle and air patrols to protect them against damage by soil movement and third part interference. Because [...]
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Conformance monitoring approaches in current and future air traffic control environments
R. Hansman, T. Reynolds

Collection of open conferences in research transport (2003). Vol. 2003, 53

Abstract
Conformance monitoring is of fundamental importance to ATC operations and future surveillance environments may enable more sophisticated procedures to be developed for this task. A Conformance Monitoring Analysis Framework has been presented which enables model-based fault detection and isolation techniques to be employed to investigate many important issues. The essential concepts of Conformance Residual generation; decision-making and intent inferencing have been identified and a lateral trajectory case study using a very simple Conformance Monitoring Model has been used to illustrate the promise of this approach for investigating different state environments. Preliminary results indicate potential improved time-to-detection performance associated with using relevant higher order states in addition to position, but this is at the expense of greater noise in the Conformance Residual.
Abstract
Conformance monitoring is of fundamental importance to ATC operations and future surveillance environments may enable more sophisticated procedures to be developed for this [...]
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FutureFlight Central: A Revolutionary Air Traffic Control Tower Simulation Facility
N. Dorighi, B. Sullivan

Collection of open conferences in research transport (2003). Vol. 2003, 52

Abstract
new air traffic control tower research facility dedicated to countering potential air and runway traffic problems at commercial airports is advancing the state- of-the-art in aviation research at the National Aeronautics and Space Administration (NASA) Ames Research Center. FutureFlight Central (FFC), is a unique real-time simulator designed to safely study new technologies, airport design changes or redesigns, and procedural changes in a virtual reality setting. The facility consists of a full-scale control tower, which depicts a 360-degree view of the airport under various weather conditions and times of day. Actual air traffic controllers operate the tower and communicate with pilots, ramp controllers and vehicle operators. "Humans-in-the-loop" provide a key distinction between conventional fast time simulation and what NASA has created in FFC. Human factors such as situational awareness, reaction time, visual perception and oral communication validate new designs and tools at a significantly higher level of accuracy and confidence. Recent integration of the tower with full- mission flight simulation allows assessment of airport changes from both the controller and pilot perspectives. With this new capability, technology developers, airport planners, and airline representatives are able to make more informed decisions. This paper describes the capabilities of FutureFlight Central, provides examples of typical projects, and addresses future applications.
Abstract
new air traffic control tower research facility dedicated to countering potential air and runway traffic problems at commercial airports is advancing the state- of-the-art [...]
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Distributed Scheduling Architecture for Multi-Center Time-Based Metering
T. Hoang, J. Foster, T. Farley, G. Wong, S. Landry, S. Green

Collection of open conferences in research transport (2003). Vol. 2003, 51

Abstract
The Traffic Management Advisor (TMA) is an air traffic control automation system currently in use in seven Air Route Traffic Control Centers (ARTCCs) to enable time based metering to busy airports within their airspace. However, this system is limited to operation within a single ARTCC, within about a 200 nautical mile radius of the airport, and on relatively simple streams of traffic. The need for coordinated metering within a greater (300+ nautical mile) radius of an airport, on streams of traffic with significant branching, and across ARTCC boundaries, has been identified. Early tests revealed that TMA could not simply be scaled up to handle such a problem. Instead, a loosely coupled hierarchy of schedules, in which constraints from downstream schedules are passed upstream, is required. Such an architecture reduces the reliance on distant projections of arrival times, making schedules robust to changes in sequence and to additions of aircraft (such as aircraft departing inside the system s scheduling horizon). This architecture is also scaleable, easily reconfigurable, and can be networked together. As such, it can be adapted for use in any size or configuration of airspace and with any number of airports delivering restrictions. An implementation of this distributed scheduling architecture is currently undergoing testing in the TMA-Multi Center system. This paper describes the architecture and its motivation.
Abstract
The Traffic Management Advisor (TMA) is an air traffic control automation system currently in use in seven Air Route Traffic Control Centers (ARTCCs) to enable time based [...]
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Inflight Icing Educational Objectives for Air Carrier Pilots
S. Green, J. Bracken, B. Moe

Collection of open conferences in research transport (2003). Vol. 2003, 50

Abstract
During the early development of commercial air transportation, inflight icing was approached with a policy of avoidance. This policy was applied through a body of knowledge gained through experience. Pilots learned where and when to expect icing encounters, and they developed operational strategies to avoid it. However, the quality of forecasting was not sufficient to reliably predict icing encounters. Thus, manufacturers took the approach of equipping aircraft used in scheduled air transportation with ice protection systems. Currently, general aviation pilots still approach icing with a policy of avoidance. However, commercial transport pilots must rationalize a dual approach. While avoidance remains the best approach, the volume of air traffic and the constraints upon routing imposed by hub operations place heavy restrictions on the avoidance option. A study has been made of 120 accidents involving air carrier aircraft in the United States and, to a limited extent, Canada. The data from these accidents has been compiled and used to evaluate the paradigm is use today, and to identify changes necessary to improve the core knowledge possessed by the air carrier pilot.
Abstract
During the early development of commercial air transportation, inflight icing was approached with a policy of avoidance. This policy was applied through a body of knowledge [...]
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A reordering-free multipath traffic engineering architecture for DiffServ-MPLS networks
E. Karasan, I. Hokelek, M. Atik, N. Akar

Collection of open conferences in research transport (2003). Vol. 2003, 49

Abstract
Date of Conference: 1-3 Oct. 2003 Conference name: Proceedings of the 3rd IEEE Workshop on IP Operations & Management (IPOM 2003) We propose a novel traffic engineering architecture for IP networks with multiprotocol label switching (MPLS) backbones. In this architecture, two (primary and secondary) label switched paths (LSPs) are established among every pair of IP routers located at the edge of an MPLS cloud. Traffic between a source-destination pair is then split between the primary and secondary LSPs using an ABR-like explicit-rate feedback gathered from the network. Taking into consideration the packet reordering effect of packet-based load balancing schemes, we propose a novel traffic splitting mechanism that operates on a per-flow basis. We show, using a variety of scenarios, that deploying flow-based multipath traffic engineering not only provides significantly and consistently better throughput than that of a single path, but is also void of any packet reordering. © 2003 IEEE.
Abstract
Date of Conference: 1-3 Oct. 2003 Conference name: Proceedings of the 3rd IEEE Workshop on IP Operations & Management (IPOM 2003) We propose a novel traffic engineering architecture [...]
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Robust hybrid control from a behavioural perspective
B. Anderson, T. Moor, J. Davoren

Collection of open conferences in research transport (2003). Vol. 2003, 48

Abstract
This paper investigates the synthesis of discrete supervisors for hybrid systems where the control objective is to enforce a language inclusion specification in the presence of plant's uncertainty. The discussion is set within Willems' behavioural system theory, where we find a relationship between the robustness of closed-loop performance and earlier results on abstraction based synthesis. From this relationship, we develop our main result: a method for the synthesis of robust supervisory controllers. Note that virtually any engineering system must possess a certain amount of robustness in order to fulfil even minimal reliability requirements. This commonly accepted fact is of a particular importance for hybrid control systems, since the motivating application areas are safety-critical and high-confidence systems as air traffic control or medical instrumentation.
Abstract
This paper investigates the synthesis of discrete supervisors for hybrid systems where the control objective is to enforce a language inclusion specification in the presence [...]
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Distributed Air/Ground Traffic Management Simulation: Results, Progress and Plans
P. Lee, T. Callantine, J. Mercer, S. Shelden, W. Johnson, E. Palmer, T. Prevot, N. Smith, V. Battiste

Collection of open conferences in research transport (2003). Vol. 2003, 47

Abstract
mixed-fidelity simulation environment for humanin-the-loop study of Distributed Air / Ground – Traffic Management (DAG-TM) concepts has been developed at NASA’s Ames Research Center. The simulation environment facilitates large-scale experiments supporting high numbers of pilot, air traffic controller, and air traffic manager participants. Decision Support Tools (DST) for flight crews and air traffic service providers are accessible at the respective operator stations. Many operator positions can be augmented or autonomously run with agent support. We present samplings of results from studies conducted using this environment, and outline our goals in terms of improving and refining the simulation. We review the overall simulation architecture, and the key upgrades, including
Abstract
mixed-fidelity simulation environment for humanin-the-loop study of Distributed Air / Ground – Traffic Management (DAG-TM) concepts has been developed at NASA’s Ames Research [...]
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Flow assignment and packet scheduling for multipath networks
V. Li, K. Leung

Collection of open conferences in research transport (2003). Vol. 2003, 46

Abstract
We propose a framework to study how to route packets efficiently in multipath communication networks. Two traffic congestion control techniques, namely, flow assignment and packet scheduling, have been investigated. The flow assignment mechanism defines an optimal splitting of data traffic on multiple disjoint paths. The resequencing delay and the usage of the resequencing buffer can be reduced significantly by properly scheduling the sending order of all packets, say, according to their expected arrival times at the destination. We consider a multiple-node M/M/1 tandem network with a delay line as the path model. When end-to-end path delays are all Gaussian distributed, our analytical results show that the techniques are very effective in reducing the average end-to-end path delay, the average packet resequencing delay, and the average resequencing buffer occupancy for various path configurations. These promising results can form a basis for designing future adaptive multipath protocols.
Abstract
We propose a framework to study how to route packets efficiently in multipath communication networks. Two traffic congestion control techniques, namely, flow assignment and [...]
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Transient Flow Analysis of Fast Valve Closure in Short Pipelines
C. Barreto, R. Ladeia, L. Pires

Collection of open conferences in research transport (2004). Vol. 2004, 50

Abstract
The present papers presents an analysis of transient pressure behavior in short pipelines for tanker’s loading at a marine terminal. The analysis was focused on the interaction of several dynamic components that are present in the line, such as check, flow control and block valves, pump and pipe elasticity. The purpose of the analysis is to maximize flow rate through the line thereby minimizing tankers dockage time, without exceeding the allowable pressure limits. A commercial software was employed in the calculations that were able to reveal the complex interaction of the dynamic components present.Copyright © 2004 by ASME
Abstract
The present papers presents an analysis of transient pressure behavior in short pipelines for tanker’s loading at a marine terminal. The analysis was focused on the interaction [...]
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A Flight Trajectory Model for a PC-based Airspace Analysis Tool
R. Mayer

Collection of open conferences in research transport (2003). Vol. 2003, 45

Abstract
This paper documents a method for rapid generation of aircraft flight trajectories. Rapid generation of flight trajectories is important for simulation models of air traffic that involve large numbers of aircraft, especially if complex interdependencies exist between flights and short simulation run times are required. Among the many aircraft trajectory models that have been developed, one generally observes a tradeoff between modeling detail provided by the model and its computational speed. Models that provide detailed trajectories typically require simulation run times on the order of one second per trajectory. Faster models often trade modeling detail for greater simulation speed. The model presented here was developed for applications that require simulation speeds on the order of one thousand trajectories per second and modeling detail to simulate typical flight operations in airspace close to major airports known as Terminal Radar Approach Control (TRACON) airspace. The computational speed of the model results from a discrete event simulation approach. It generates continuous speed and altitude profiles based on a small set of 31 trajectory parameters that are defined for each aircraft type based on aircraft performance data. The model provides detailed flight trajectories by synchronizing the discrete events that define model trajectories with significant events of typical flight operations and methodically adjusting the size of variable simulation time steps. The time steps, chosen in accordance with common piloting procedures and flight events, are categorized in ten flight phases. This paper introduces the concept of flight phases to group flight events and their associated trajectory parameters and presents a discrete-event flight trajectory model that is based on aircraft performance and centered on piloting procedures.
Abstract
This paper documents a method for rapid generation of aircraft flight trajectories. Rapid generation of flight trajectories is important for simulation models of air traffic [...]
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VEHIL: A Test Facility for Validation of Fault Management Systems for Advanced Driver Assistance Systems
J. Ploeg, M. Verhaegen, D. Schutter, O. Gietelink

Collection of open conferences in research transport (2004). Vol. 2004, 49

Abstract
We present a methodological approach for the validation of fault management systems for Advanced Driver Assistance Systems (ADAS). For the validation process the unique VEHIL facility, developed by TNO Automotive and currently situated in Helmond, The Netherlands, is applied. The VEHIL facility provides the opportunity to make the entire development process of intelligent vehicles safer, cheaper, and more manageable, and to make simulation more reliable. The main feature of VEHIL is that a complete intelligent vehicle, including its sensors and actuators, can be tested in a Hardware-In-the-Loop simulation environment. In this way VEHIL can be applied in the design phase for fast and easy optimization of the sensor configuration. Moreover, due to its ability for providing very accurately controllable testing conditions, VEHIL can also be used for the validation of the performance of intelligent vehicle control and fault management systems. In this paper, we particularly focus on the use of VEHIL for the validation of fault management systems for Advanced Driver Assistance Systems.
Abstract
We present a methodological approach for the validation of fault management systems for Advanced Driver Assistance Systems (ADAS). For the validation process the unique VEHIL [...]
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Internet packet traffic congestion
D. Arrowsmith, M. Woolf, J. Pitts, R. Mondrdgon-C

Collection of open conferences in research transport (2003). Vol. 2003, 43

Abstract
In recent years various models for packet traffic in networks have been developed. Most models have used Poisson-like sources which replicate traffic that is voice type. Such sources are said to be short-range-dependent (SRD). The early models of Sole and Valverde demonstrated that long-range-dependent (LRD) traffic could arise in the queue length dynamics at a given node within a communications network even when the sources are LRD free. In this paper we consider the nature of the onset of congestion as load is increased in various types of network (regular, small-world and scale-free) and contrast their congestion behaviour by considering packet latency, or lifetime, indicators.
Abstract
In recent years various models for packet traffic in networks have been developed. Most models have used Poisson-like sources which replicate traffic that is voice type. Such [...]
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Preliminary design and evaluation of portable electronic flight progress strips
R. Hansman, N. Doble

Collection of open conferences in research transport (2003). Vol. 2003, 42

Abstract
There has been growing interest in using electronic alternatives to the paper Flight Progress Strip (FPS) for air traffic control. However, most research has been centered on radar-based control environments, and has not considered the unique operational needs of the airport air traffic control tower. Based on an analysis of the human factors issues for control tower Decision Support Tool (DST) interfaces, a requirement has been identified for an interaction mechanism which replicates the advantages of the paper FPS (e.g., head-up operation, portability) but also enables input and output with DSTs. An approach has been developed which uses a Portable Electronic FPS that has attributes of both a paper strip and an electronic strip. The prototype flight strip system uses Personal Digital Assistants (PDAs) to replace individual paper strips in addition to a central management interface which is displayed on a desktop computer. Each PDA is connected to the management interface via a wireless local area network. The Portable Electronic FPSs replicate the core functionality of paper flight strips and have additional features which provide a heads-up interface to a DST. The central management interface is used for aircraft scheduling and sequencing and provides an overview of airport departure operations. This paper presents the design of the Portable Electronic FPS system as well as preliminary evaluation results.
Abstract
There has been growing interest in using electronic alternatives to the paper Flight Progress Strip (FPS) for air traffic control. However, most research has been centered [...]
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An Air Traffic Simulation Model that Predicts and Prevents Excess Demand
J. Boesel

Collection of open conferences in research transport (2003). Vol. 2003, 41

Abstract
n airplane’s ability to absorb delay while airborne is limited and costly. Because of this, the air traffic management system anticipates and manages excessive demand for scarce shared resources, such as arrival runways or busy airspace, so that the delay necessary for buffering can be spread out over a larger distance, or taken on the ground before departure. It is difficult to model these important dynamics in a standard queueresource simulation framework, which does not account for limited delay absorption capacity. The modeling methodology presented here captures these dynamics by employing a large number of independent threads of execution to monitor and enforce a large number of relatively simple mathematical relationships. These relationships calculate feasible time windows for each portion of each flight. The model was implemented in the SLX simulation language. The speed and scalability of SLX are essential to the approach, which would otherwise be impractical.
Abstract
n airplane’s ability to absorb delay while airborne is limited and costly. Because of this, the air traffic management system anticipates and manages excessive demand for [...]
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IFR Operations at Non-Towered/Non-Radar Airports: Can We do Better Than One-at-a-Time?
C. Adams, K. Jones, T. Abbott, D. Williams, M. Consiglio

Collection of open conferences in research transport (2003). Vol. 2003, 40

Abstract
This paper describes a new concept for operations in non-radar terminal airspace around small, nontowered airports. Currently, air traffic operations in instrument meteorological conditions (IMC) at airfields without control towers and radar service are severely constrained by what is known as the one-in/one-out paradigm. Under these conditions only one operation (either arrival or departure) is allowed to occur at a time. Since these operations can take over 15 minutes to complete, capacity at these airports is severely restricted in IMC. The proposed concept is an attempt to break this current paradigm by applying emerging airborne and ground-based technologies to enable simultaneous operations by multiple aircraft in nonradar terminal airspace around small non-towered airports in IMC. The general philosophy underlying this concept of operations is the establishment of a newly defined area surrounding these airports called a Self-Controlled Area (SCA). Aircraft operating within the SCA are required to have a specified minimum level of equipage. Within the SCA, pilots are responsible for separating themselves from other similarly equipped aircraft through the use of new onboard systems and procedures. This concept also takes advantage of newly developed automation at the airport, which provides appropriate sequencing information to the pilots for safe and improved operations. Such operations would enhance the opportunity for point-to-point air taxi or charter operations into smaller airfields that are closer to a traveler s origin and destination. A description of this concept of operations and a simulation environment used for evaluation is provided in this paper.
Abstract
This paper describes a new concept for operations in non-radar terminal airspace around small, nontowered airports. Currently, air traffic operations in instrument meteorological [...]
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Agent-Based Support for Distributed Air/Ground Traffic Management Simulation Research
T. Prevot, W. Johnson, V. Battiste, T. Callantine

Collection of open conferences in research transport (2003). Vol. 2003, 39

Abstract
NASA researchers are extending a large-scale distributed simulation to assess the feasibility, benefits, and scalability of Distributed Air/Ground Traffic Management (DAG-TM) concepts. This paper describes applications of software agents to support these efforts. This paper identifies applications ranging from assistants to replacements for human confederate participants and support personnel. The applications span air traffic control positions, flight simulators, pseudoaircraft control stations, and simulation support functions. The paper first provides an overview of the DAG-TM simulation, including the Multi Aircraft Control System (MACS), and describes the responsibilities of various participants. It then discusses agent applications that address problems and leverage capabilities demonstrated in previous research. Of particular interest are agents that can control air traffic and pilot aircraft, implemented within the MACS framework. Agents provide a means for focusing required subject training, reducing variability and problems attributable to human confederates, supporting partially staffed and part-task studies within the full simulation environment, and enabling fast-time simulations to investigate DAG-TM concept scalability. The paper concludes with a discussion that emphasizes the importance of interplay between complementary human-in-the-loop and agent-based simulations. This research constitutes one facet of the Distributed Air/Ground Traffic Management element of the NASA Aviation System Capacity Program Advanced Air Transportation Technologies project.
Abstract
NASA researchers are extending a large-scale distributed simulation to assess the feasibility, benefits, and scalability of Distributed Air/Ground Traffic Management (DAG-TM) [...]
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Detection and Location of Damage on Pipelines
K. Moore, J. Richardson, R. Carrington

Collection of open conferences in research transport (2004). Vol. 2004, 44

Abstract
The U.S. Dept of Energy Idaho National Engineering and Environmental Laboratory (INEEL) has developed and successfully tested a real-time pipeline damage detection and location system. This system uses porous metal resistive traces applied to the pipe to detect and locate damage. The porous metal resistive traces are sprayed along the length of a pipeline. The unique nature and arrangement of the traces allows locating the damage in real time along miles of pipe. This system allows pipeline operators to detect damage when and where it is occurring, and the decision to shut down a transmission pipeline can be made with actual real-time data, instead of conservative estimates from visual inspection above the area.Copyright © 2004 by ASME
Abstract
The U.S. Dept of Energy Idaho National Engineering and Environmental Laboratory (INEEL) has developed and successfully tested a real-time pipeline damage detection and location [...]
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Motivation-based approach to behavior prediction
D. Reichardt, I. Dagli

Collection of open conferences in research transport (2003). Vol. 2003, 38

Abstract
The design of advanced driver assistance systems always aims at enabling the driver to master today's traffic in a more safe and comfortable way. In order to judge the risks in a situation, the assistance system must be able to predict traffic behavior. Taking into account all possible future situations for the next few seconds is a task which quickly produces a complexity that can hardly be handled. Taking the human driver as a role model for its software-counterpart, we propose a new concept which aims at modeling anticipation by taking the motivations of drivers as a basis. Starting with a set of motivations typical for highway traffic, concrete situation specific goals are derived. A planning component generates the possible and fulfillable plans for all vehicles with respect to the goals. Then, the observed actions of the vehicles around are compared to these plans in order to derive a plausibility for the underlying intentions. Eventually, prediction is performed for plausible behaviors of vehicles, which are always based on a motivation that can be taken as an explanation for it. First results are shown in simulation for highway exit scenarios.
Abstract
The design of advanced driver assistance systems always aims at enabling the driver to master today's traffic in a more safe and comfortable way. In order to judge the risks [...]
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Helicopter in-flight tracking system (HITS) for the Gulf of Mexico
P. Martone, A. Daskalakis

Collection of open conferences in research transport (2003). Vol. 2003, 36

Abstract
Helicopters and other low-altitude air traffic over the Gulf of Mexico operate without the benefit of radar surveillance due to the location and range of existing onshore radar installations. The NASA Ames Research Center (ARC) is sponsoring deployment and testing of a prototype helicopter in-flight tracking system (HITS) in a portion of the Gulf of Mexico offshore area. Using multilateration principles, HITS determines the location and altitude of all transponder-equipped aircraft without requiring changes to current mode A, C or S transponders. In addition to multilateration, HITS provides surveillance reports for aircraft equipped for automatic dependent surveillance roadcast (ADS-B). This paper describes the HITS project - specifically, the system equipment (architecture, remote sensors, central processing site, and communications equipment) and system performance (accuracy, coverage, and reliability).
Abstract
Helicopters and other low-altitude air traffic over the Gulf of Mexico operate without the benefit of radar surveillance due to the location and range of existing onshore [...]
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A Review of the Time Dependent Behaviour of Line Pipe Steel
A. Cosham, P. Hopkins

Collection of open conferences in research transport (2004). Vol. 2004, 43

Abstract
It is good practice to reduce the pressure in a pipeline prior to inspecting damage. One of the purposes of this pressure reduction is to prevent a ‘time dependent failure’ whilst inspecting the damage. The EPRG (European Pipeline Research Group) guidelines for the assessment of mechanical damage recommend that the internal pressure be reduced to 85 percent of the pressure at the time of damage to prevent time dependent failures. The PRCI (Pipeline Research Council International) Pipeline Repair Manual recommends a pressure reduction to 80 percent of the pressure at the time of damage. Failures that occur under a constant load are time dependent failures. This means that a defect in a pipeline could fail sometime after the damage was caused, even though there has been no increase in the applied load, or an active growth mechanism such as corrosion or fatigue. They have been observed during hydrostatic test hold periods, during operation and under laboratory conditions. Failures under constant load occur because plastic deformation occurs in the material surrounding a defect subject to a load, and because plasticity is time dependent. Time dependent behaviour is relevant to: (1) the safe working practices in the vicinity of a damaged pipeline, (2) pressure reversals, (3) the margin between the operating pressure and the hydrostatic test pressure, and (4) the minimum duration of a hydrotest. The results of experimental and analytical studies of time dependent behaviour reported in the published literature are reviewed in this paper, to understand the background to the above recommended pressure reductions. This paper is based on the findings of the Pipeline Defect Assessment Manual (PDAM) project, a Joint Industry Project sponsored by sixteen international oil and gas companies.Copyright © 2004 by ASME
Abstract
It is good practice to reduce the pressure in a pipeline prior to inspecting damage. One of the purposes of this pressure reduction is to prevent a ‘time dependent failure’ [...]
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A fast heuristic for genetic algorithms in link weight optimization
C. Reichert, T. Magedanz

Collection of open conferences in research transport (2004). Vol. 2004, 42

Abstract
Genetic algorithms are a useful tool for link weight optimization in intra-domain traffic engineering where the maximum link load is to be minimized. As a local heuristic, the weight of the maximum loaded link is increased to speed up the search for a near-optimal solution. We show that implementing this heuristic as directed mutation outperforms an implementation as an inner loop in both quality of the result and number of calls to the objective function when used together with caching. Optimal mutation rates result in surprisingly high cache hit ratios.
Abstract
Genetic algorithms are a useful tool for link weight optimization in intra-domain traffic engineering where the maximum link load is to be minimized. As a local heuristic, [...]
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Coarse-grain pipelining on multiple FPGA architectures
M. Hall, H. Ziegler, B. So, P. Diniz

Collection of open conferences in research transport (2003). Vol. 2003, 35

Abstract
Reconfigurable systems, and in particular, FPGA-based custom computing machines, offer a unique opportunity to define application-specific architectures. These architectures offer performance advantages for application domains such as image processing, where the use of customized pipelines exploits the inherent coarse-grain parallelism. In this paper we describe a set of program analyses and an implementation that map a sequential and un-annotated C program into a pipelined implementation running on a set of FPGAs, each with multiple external memories. Based on well-known parallel computing analysis techniques, our algorithms perform unrolling for operator parallelization, reuse and data layout for memory parallelization and precise communication analysis. We extend these techniques for FPGA-based systems to automatically partition the application data and computation into custom pipeline stages, taking into account the available FPGA and interconnect resources. We illustrate the analysis components by way of an example, a machine vision program. We present the algorithm results, derived with minimal manual intervention, which demonstrate the potential of this approach for automatically deriving pipelined designs from high-level sequential specifications.
Abstract
Reconfigurable systems, and in particular, FPGA-based custom computing machines, offer a unique opportunity to define application-specific architectures. These architectures [...]
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Innovative Nondestructive Method Determines Fracture Toughness of In-Service Pipelines
F. Haggag, L. Phillips

Collection of open conferences in research transport (2004). Vol. 2004, 39

Abstract
Applications of the innovative, patented Stress-Strain Microprobe (SSM) system, that utilizes an in-situ nondestructive Automated Ball Indentation (ABI) test technique to determine fracture toughness of in-service steel pipelines, are described in this paper. The ABI test provides the actual/current values of fracture toughness properties for base metal, welds, and heat-affected-zones. The ABI-measured key mechanical properties are used with other nondestructive measurements, such as crack/defect sizes (determined from in-line smart pigs or from on-line ultrasound instruments), to determine the safe operating pressure of the pipeline or to necessitate certain rehabilitation actions. The ABI test is based on progressive indentation with intermediate partial unloadings until the desired/required maximum depth (maximum strain) is reached, and then the indenter is fully unloaded. The ABI test is fully automated (using a notebook computer, data acquisition system, and a servo motor), and a single test is completed in less than two minutes. This paper describes two recent field investigations. The first investigation assessed a catastrophic failure that occurred in a natural gas plant on a cold winter night shortly following the leak of liquid natural gas into a natural gas pipeline. The combination of cold temperature and high strain rate near a crack resulted in the destruction of approximately a 12-meter section of a 508-mm (20-inch) diameter pipeline into several hundred small pieces. Since the remaining pieces from the exploded pipeline section were not sufficient to machine destructive tensile and fracture toughness specimens, the SSM system was used to measure the tensile and fracture toughness properties from multiple ABI tests on several pipeline pieces. The ABI-measured tensile and fracture toughness results provided the basis for the fitness-for-service assessment of the remaining pipeline sections of the natural gas plant. The second application involved a fire that occurred due to a leak from a 356-mm (14-inch) diameter Kerosene pipeline. The fire-damaged section of the pipeline was cut out and replaced. As part of the effort to prevent future accidents, the entire 7-km pipeline needed a structural integrity assessment. In-Situ ABI tests were conducted to measure the tensile and fracture toughness properies, from each ABI test, for the fitness-for-service assessment since the carbon steel pipeline had undocumented grade.
Abstract
Applications of the innovative, patented Stress-Strain Microprobe (SSM) system, that utilizes an in-situ nondestructive Automated Ball Indentation (ABI) test technique to [...]
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"title"Automatic acquisition of motion trajectories: tracking hockey players"/title"
J. Little, K. Okuma, D. Lowe

Collection of open conferences in research transport (2003). Vol. 2003, 34

Abstract
Computer systems that have the capability of analyzing complex and dynamic scenes play an essential role in video annotation. Scenes can be complex in such a way that there are many cluttered objects with different colors, shapes and sizes, and can be dynamic with multiple interacting moving objects and a constantly changing background. In reality, there are many scenes that are complex, dynamic, and challenging enough for computers to describe. These scenes include games of sports, air traffic, car traffic, street intersections, and cloud transformations. Our research is about the challenge of inventing a descriptive computer system that analyzes scenes of hockey games where multiple moving players interact with each other on a constantly moving background due to camera motions. Ultimately, such a computer system should be able to acquire reliable data by extracting the players’ motion as their trajectories, querying them by analyzing the descriptive information of data, and predict the motions of some hockey players based on the result of the query. Among these three major aspects of the system, we primarily focus on visual information of the scenes, that is, how to automatically acquire motion trajectories of hockey players from video. More accurately, we automatically analyze the hockey scenes by estimating parameters (i.e., pan, tilt, and zoom) of the broadcast cameras, tracking hockey players in those scenes, and constructing a visual description of the data by displaying trajectories of those players. Many technical problems in vision such as fast and unpredictable players' motions and rapid camera motions make our challenge worth tackling. To the best of our knowledge, there have not been any automatic video annotation systems for hockey developed in the past. Although there are many obstacles to overcome, our efforts and accomplishments would hopefully establish the infrastructure of the automatic hockey annotation system and become a milestone for research in automatic video annotation in this domain.
Abstract
Computer systems that have the capability of analyzing complex and dynamic scenes play an essential role in video annotation. Scenes can be complex in such a way that there [...]
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Intelligent imaging systems for automotive applications
Y. Huang, S. Fu, C. Thompson

Collection of open conferences in research transport (2003). Vol. 2003, 33

Abstract
In common with many other application areas, visual signals are becoming an increasingly important information source for many automotive applications. For several years CCD cameras have been used as research tools for a range of automotive applications. Infrared cameras, RADAR and LIDAR are other types of imaging sensors that have also been widely investigated for use in cars. This paper will describe work in this field performed in C2VIP over the last decade - starting with Night Vision Systems and looking at various other Advanced Driver Assistance Systems. Emerging from this experience, we make the following observations which are crucial for "intelligent’ imaging systems: 1. Careful arrangement of sensor array. 2. Dynamic-Self-Calibration. 3. Networking and processing. 4. Fusion with other imaging sensors, both at the image level and the feature level, provides much more flexibility and reliability in complex situations. We will discuss how these problems can be addressed and what are the outstanding issues.
Abstract
In common with many other application areas, visual signals are becoming an increasingly important information source for many automotive applications. For several years CCD [...]
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