Scipedia: Documents published in 2017

Real time analytics of urban congestion trajectories on hadoop-mongoDB cloud ecosystem

Scipedia content — Fri, 29 Jan 2021 00:48:17 +0100

Cities should invest significant budgets on technologies of the Internet of things in the next few years. One of the great challenges is to align technologies related to connected objects exploring the urban-cloud computing and big data analytics to intelligent urban traffic and congestion management. Traffic congestion in urban networks takes polymorphic forms and magnitudes. Technological advances on big data analytics, distributed processing on the cloud as well as new technologies of location-based services and traffic measurement are great support for the congestion management processes. This paper mainly discussed to formulate a new model of urban traffic congestion based on the trajectories meta-model and on some new algebraic structures. The idea is to consider congestion as a space-time event and its extent as a wave spreading modelled by a space-time path trajectory. It is also considering the issue of congestion such as infections that spread in a network. We define two algebra structures that meet the expectations of congestion management. These algebraic structures generate very useful congestion patterns for network traffic control and monitoring functions. For congestion trajectories temporal queries, mining purpose, and spatio-temporal visualization, these spacetime congestion paths will be stored in a MongoDB data warehouse operating in a Hadoop cloud-based eco-system. This approach is of great simplicity we have to operate later in the traffic management schemes.

Learning Policies for Resolving Demand-Capacity Imbalances During Pre-tactical Air Traffic Management

Scipedia content — Fri, 29 Jan 2021 00:40:57 +0100

Summarization: In this work we propose and investigate the use of collaborative reinforcement learning methods for resolving demand-capacity imbalances during pre-tactical Air Traffic Management. By so doing, we also initiate the study of data-driven techniques for predicting multiple correlated aircraft trajectories; and, as such, respond to a need identified in contemporary research and practice in air-traffic management. Our simulations, designed based on real-world data, confirm the effectiveness of our methods in resolving the demand-capacity problem, even in extremely hard scenarios. Παρουσιάστηκε στο: 15th German Conference on Multiagent System Technologie

An Elementary Algorithm for Autonomous Air Terminal Merging and Interval Management

Scipedia content — Fri, 29 Jan 2021 00:36:56 +0100

central element of air traffic management is the safe merging and spacing of aircraft during the terminal area flight phase. This paper derives and examines an algorithm for the merging and interval managing problem for Standard Terminal Arrival Routes. It describes a factor analysis for performance based on the distribution of arrivals, the operating period of the terminal, and the topology of the arrival routes; then presents results from a performance analysis and from a safety analysis for a realistic topology based on typical routes for a runway at Phoenix International Airport. The heart of the safety analysis is a statistical derivation on how to conduct a safety analysis for a local simulation when the safety requirement is given for the entire airspace.

Computing New Optimized Routes for GPS Navigators Using Evolutionary Algorithms

Scipedia content — Fri, 29 Jan 2021 00:28:22 +0100

GPS navigators are now present in most vehicles and smartphones. The usual goal of these navigators is to take the user in less time or distance to a destination. However, the global use of navigators in a given city could lead to traffic jams as they have a highly biased preference for some streets. From a general point of view, spreading the traffic throughout the city could be a way of preventing jams and making a better use of public resources. We propose a way of calculating alternative routes to be assigned by these devices in order to foster a better use of the streets. Our experimentation involves maps from OpenStreetMap, real road traffic, and the microsimulator SUMO. We contribute to reducing travel times, greenhouse gas emissions, and fuel consumption. To analyze the sociological aspect of any innovation, we analyze the penetration (acceptance) rate which shows that our proposal is competitive even when just 10% of the drivers are using it. Spanish MINECO project TIN2014-57341-R (http://moveon.lcc.uma.es). FPU grant (FPU13/00954) from the Spanish Ministry of Education, Culture and Sports. University of Malaga. International Campus of Excellence Andalucia TECH.

ECommerce - growing globally and driving logistics innovations. Fachsequenz Urbane Logistik: Presentation held at Air Cargo Conference, 30. August 2018, HOLM, Frankfurt am Main

Scipedia content — Fri, 29 Jan 2021 00:16:33 +0100

Drivers and Driver Assistance Systems: How Well do They Match?

Scipedia content — Fri, 29 Jan 2021 00:15:45 +0100

The demantic container approach: techniques for ontology-based data description and discovery in a decentralized SWIM knowledge base

Scipedia content — Fri, 29 Jan 2021 00:04:59 +0100

System Wide Information Management (SWIM) inAir Traffic Management (ATM) aims to facilitate access to ATM information via information services, thereby fostering common situational awareness among stakeholders. The development of information services and applications with added value in SWIM will comprise finding, selecting, filtering and composition ofdata/information from different sources, which is also referred to as ‘data logic’. Semantic containers are a means to encapsulate the data logic and clearly separate it from business and presentation logic. The provisioning of semantic containers for a specific purpose encompasses the discovery of existing source containers and often further value-adding processing steps such as filtering and annotation. Common semantic web technologies may serve to implement the semantic container approach

Diagnosing Machine Learning Pipelines with Fine-grained Lineage

Scipedia content — Fri, 29 Jan 2021 00:04:40 +0100

We present the Hippo system to enable the diagnosis of distributed machine learning (ML) pipelines by leveraging fine-grained data lineage. Hippo exposes a concise yet powerful API, derived from primitive lineage types, to capture fine-grained data lineage for each data transformation. It records the input datasets, the output datasets and the cell-level mapping between them. It also collects sufficient information that is needed to reproduce the computation. Hippo efficiently enables common ML diagnosis operations such as code debugging, result analysis, data anomaly removal, and computation replay. By exploiting the metadata separation and high-order function encoding strategies, we observe an O(10^3)x total improvement in lineage storage efficiency vs. the baseline of cell-wise mapping recording while maintaining the lineage integrity. Hippo can answer the real use case lineage queries within a few seconds, which is low enough to enable interactive diagnosis of ML pipelines.

Bus Route Design for Different Vehicle Models Considering Environmental Factors

Scipedia content — Thu, 28 Jan 2021 23:49:25 +0100

International audience; Bus transit plays an important role in commuters' daily life in urban areas. The energy efficiency of bus transit impacts not only on the passengers' travel cost but also the urban environment. The traditional transit vehicles, such as Compressed Natural Gas (CNG) and diesel buses, generate massive Green House Gas (GHG) and pollutants while operating in urban streets. In contrast, zero-emission buses, such as supercharge bus and electric bus, entail environmental friendliness but require huge initial investment for fleet purchase. Conventional bus route design largely ignored the environmental factors. Thus, the air pollutions may be enhanced by the flawed design of bus stop locations because of the frequent and inefficient deceleration and acceleration at stops. In this paper, a multi-period (peak hour and off-peak hour) continuum model will be built to optimize the design of a bus route for different vehicle models (i.e., supercharge bus, electric bus, CNG, and diesel bus). Environmental cost will be explicitly considered. A case study is conducted in Yaan City (China), where the 1 st supercharge bus route is in operation. Comparing with current design, the optimal result indicates that the average stop spacing can be further reduced by up to 13%, and the peak hour headway should be further shorted, which results in less access time and waiting time. Furthermore, we examined our results against those using discrete model to verify accuracy. The results show that the outcomes of continuum and discrete model are in the neighborhood (with an error less than 3%).The proposed model and solution method are demonstrated for practical implementation in urban route design.

A realization method of multi-protocol label switching traffic engineering based on logical hierarchy

Scipedia content — Thu, 28 Jan 2021 23:46:38 +0100

The importance of ergonomic principles in design of the traffic signs for childeren

Scipedia content — Thu, 28 Jan 2021 23:37:13 +0100

Children represent a vulnerable population from the standpoint of traffic safety. A modern traffic poses complex and high requirements to all its participants, and among them, particularly to young children. Children have a higher risk of pedestrian injuries. Children are experiencing experience traffic differently from adults. How do children view the world? What helps them to link with their environment? How do children imagine traffic signs? To address these questions, this study examines how fast the children (between 6 and 10 years of age) react to traffic signs mounted at different heights. The analysis of the results indicated that there were differences in mean reaction time for traffic signs of different heights. Children best perceive a traffic sign when it is mounted at 1.9 m. The research highlights the importance of ergonomic principles in choosing the appropriate height of traffic signs for children.

Towards scenario-based security requirements engineering for cyber-physical systems

Scipedia content — Thu, 28 Jan 2021 23:30:00 +0100

Cyber-physical systems are characterized among others by strong interconnection with each other, but also with their environment. This interconnection enables on the one hand new functionality with a high complexity and leads on the other hand to a high demand on the security of the systems. Both aspects require tailored development processes with a rigorous requirements engineering. However, current requirements engineering approaches focus either on the functional or on the security aspects but lack an integrated view on modeling and analysing both aspects. Therefore, we present in this paper ongoing research for a formal, model- and scenario-based requirements engineering approach for cyber-physical systems. Our approach enables the requirements engineer in an early stage of the development whether the modeled security requirements are sufficient to mitigate attacks and whether the security requirements influence the functional behavior. We illustrate the approach by means of an advanced driver assistance system from the automotive domain.

The Use of a Multi-modal Interface to Integrate In-Vehicle Information Presentation

Scipedia content — Thu, 28 Jan 2021 23:19:21 +0100

The car of the future will have many new information sources - including telematics systems, navigation systems and Advanced Driver Assistance Systems (ADAS) - that will compete for a driver's limited cognitive attention. If they are implemented as completely separate systems then cognitive overload and driver distraction are inevitable outcomes. However, if they are implemented as an integrated intelligent system with a multi-modal interface, then the benefits of such functionality will be achieved with much less impact on driving safety. Such a system will support the task of safe driving by filtering and mediating information in response to real-world driving demands. This paper outlines the human factors research program being undertaken by Motorola Labs to evaluate key elements of such a multi-model interface as well as the key human factors issues involved in a multi-modal interface.

A flexible modeling approach for robust multi-lane road estimation

Scipedia content — Thu, 28 Jan 2021 23:16:11 +0100

robust estimation of road course and traffic lanes is an essential part of environment perception for next generations of Advanced Driver Assistance Systems and development of self-driving vehicles. In this paper, a flexible method for modeling multiple lanes in a vehicle in real time is presented. Information about traffic lanes, derived by cameras and other environmental sensors, that is represented as features, serves as input for an iterative expectation-maximization method to estimate a lane model. The generic and modular concept of the approach allows to freely choose the mathematical functions for the geometrical description of lanes. In addition to the current measurement data, the previously estimated result as well as additional constraints to reflect parallelism and continuity of traffic lanes, are considered in the optimization process. As evaluation of the lane estimation method, its performance is showcased using cubic splines for the geometric representation of lanes in simulated scenarios and measurements recorded using a development vehicle. In a comparison to ground truth data, robustness and precision of the lanes estimated up to a distance of 120 m are demonstrated. As a part of the environmental modeling, the presented method can be utilized for longitudinal and lateral control of autonomous vehicles.

Adiabatic approach for natural gas pipeline computations

Scipedia content — Thu, 28 Jan 2021 23:10:22 +0100

We consider slowly evolving, i.e. ADIABATIC, operational regime within a transmission level (continental scale) natural gas pipeline system. This allows us to introduce a set of nodal equations of reduced complexity describing gas transients in injection/consumption UNBALANCED (so-called line-pack) cases. We discuss, in details, construction of the UNBALANCED ADIABATIC (UA) approximation on the basic example of a single pipe. The UA approximation is expected to play a significant "model reduction" role in solving control, optimization and planning problems relevant for flawless functioning of modern natural gas networks.

Comment: 6 pages, 2 figure

A Gaussian process based decision support tool for air traffic management

Scipedia content — Thu, 28 Jan 2021 22:59:52 +0100

Technological developments in the last decade have shifted challenges in traffic flow management from obtaining and storing data, to analysing and presenting the enormous amount of available trajectory data in a comprehensible manner."br/"This paper introduces a novel approach to visualising air-traffic, shifting the focus from displaying traffic density, towards directly visualising the flight corridors used by air-traffic."br/""br/"Such an approach is suitable for visualising air-traffic in three dimensions, which is particularly helpful in the vicinity of an airport where the air-traffic often changes level."br/""br/"Furthermore, the approach is data-driven, allowing the comparison of multiple trajectory datasets in order to identify changes in traffic corridors related to changing air-traffic and weather conditions."br/""br/"Finally, by using the probabilistic nature of the approach, it is possible to quantify the air-traffic complexity in terms of the traffic structure."br/""br/"The results presented in this paper show the approach applied to a trajectory dataset as measured by ground-radar near Denver airport (DEN).

SMART RIVERS 2017

Scipedia content — Thu, 28 Jan 2021 22:55:25 +0100

Peer reviewed

A Network Condition-Centric Flow Selection and Rerouting Strategy to Mitigate Air"br /" Traffic Congestion under Uncertainties

Scipedia content — Thu, 28 Jan 2021 22:41:23 +0100

The 5G-Crosshaul Packet Forwarding Element pipeline: Measurements and analysis

Scipedia content — Thu, 28 Jan 2021 22:35:30 +0100

This paper is focused on the 5G-Crosshaul Packet Forwarding Element (XPFE), which is the packet forwarding element of the 5G-Crosshaul network architecture. The XPFE integrates multiple technologies which allow to transport traffic from multiple tenants and of different nature over the same infrastructure. Hence, the paper is focused on the performance of this essential element of our network, providing some end-to-end delay measurements and analyzing the behavior of this delay. Likewise, we have fitted the appropriate probability distribution for these measurements, which allows us to infer some confidence intervals for the prediction of the maximum number of hops supported by delay-sensitive fronthaul traffic before being processed in a 5G-Crosshaul Processing Unit.

Document type: Conference object

INVESTIGATING THE EFFECT OF USING SOIL BENTONITE WALL ON DAMAGE MITIGATION OF STEEL BURIED PIPELINES SUBJECTED TO REVERSE FAULT RUPTURE

Scipedia content — Thu, 28 Jan 2021 22:22:31 +0100

Developing performance indicators for a logistics model for vessel platooning

Scipedia content — Thu, 28 Jan 2021 22:14:26 +0100

On the Role of Political Affiliation in Human Perception The Case of Delhi OddEven Experiment

Scipedia content — Thu, 28 Jan 2021 22:07:27 +0100

In an effort to curb air pollution, the city of Delhi (India), known to be one of the most populated, polluted, and congested cities in the world has run a trial experiment in two phases of 15 days intervals. During the experiment, most of four-wheeled vehicles were constrained to move on alternate days based on whether their plate numbers ended with odd or even digits. While the local government of Delhi represented by A. Kejriwal (leader of AAP party) advocated for the benefits of the experiment, the prime minister of India, N. Modi (former leader of BJP) defended the inefficiency of the initiative. This later has led to a strong polarization of public opinion towards OddEven experiment. This real-world urban experiment provided the scientific community with a unique opportunity to study the impact of political leaning on humans perception at a large-scale. We collect data about pollution and traffic congestion to measure the real effectiveness of the experiment. We use Twitter to capture the public discourse about the experiment in order to study people’s opinion within different dimensions: time, location, and topics. Our results reveal a strong influence of political affiliation on how people perceived the outcomes of the experiment. For instance, AAP supporters were significantly more enthusiastic about the success of OddEven compared to BJP supporters. However, taking into account location of people revealed that personal experience is able to overcome political bias.

Analysis of a Bidirectional Resonant Converter for Wide Battery Voltage Range in Electric Vehicles Application

Scipedia content — Thu, 28 Jan 2021 22:04:06 +0100

International audience; In this paper, an improved bidirectional resonant converter for wide battery voltage applications is proposed. The topology has a symmetrical resonant circuit which guarantees an identical behaviour for both energy transfer directions. The proposed converter has the capability to achieve soft switching for both bridges and the ability to operate under wide input/output voltage with narrow switching frequency variation. That increases the efficiency for both energy transfer directions. First harmonic approximation method (FHA) is used to define the equivalent circuit and to analyse the gain characteristics of the converter. Performances of the proposed converter for wide battery voltage application are evaluated through some simulations using Matlab/Simulink software.

Iberian motorways of the sea. An overview after 15 years of of Van Miert report

Scipedia content — Thu, 28 Jan 2021 21:55:48 +0100

fter 15 years of the Van Miert report proposing to include the Motorways of the Sea in the TEN-T schema, an overview wants to be done in the Iberian Peninsula scenario. In 2015 the Intra European trade (Eurostat, 2017) supposed around 11,263.4 millions of tons, being through Short Sea Shipping (SSS) up to 1.808,5 millions of tons and only the 13.6 % on Ro/Ro trades (246.04 millions of tons or the 2.2 % over the total volumes). In the case of Spanish Short Sea Shipping traffics raised to 196.668 millions of tons (234.7 millions of tons in 2016 from www.spc-spain.es) being only 15.33 millions of tonnes or 7.8 % under Ro/Ro schema. Keeping in mind these figures, it is asked which rate of success should be acquired with the maritime transport promotion policies in European Union. The proposed paper wants to analyse in deep, which reasons could explain the low volumes that still Intra European Short Sea Shipping gets. The analysis will begin with a review of the SSS and Motor Ways of the Sea official definition and after having a complete overview of traffic figures, to propose a model to analyse the best mode to connect different Iberian destinations offered to Consignors, in an attempt to transfer part of the cargo from road to sea option.

A Fast and Flexible Aircraft Trajectory Predictor and Optimiser for ATM Research Applications

Scipedia content — Thu, 28 Jan 2021 21:51:59 +0100

Trajectory prediction and optimisation algorithms will be the keystone for a successful trajectory based operations concept implementation, where accurate predictions and optimal trajectories will be needed for a wide variety of look-ahead times and operational contexts. The main goal of this paper is to present the architecture and capabilities of an aircraft trajectory prediction and optimisation framework suitable for various air traffic management research applications. The flexibility of this framework, called DYNAMO, allows for an easy implementation and assessment of actual and future concepts of operation, considering at the same time realistic weather data and aircraft performance models. In addition, its design enables the use for real-time applications and when a large set of trajectories needs to be rapidly generated for simulation and benchmarking purposes. The performance of the framewor

Peer Reviewed

The Influence of Cooperating Self-Driving Car to Highway

Scipedia content — Thu, 28 Jan 2021 21:47:44 +0100

The Design of Haptic Gas Pedal Feedback to Support Eco-Driving

Scipedia content — Thu, 28 Jan 2021 21:46:22 +0100

Previous literature suggests that haptic gas pedals can assist the driver in search of maximum fuel economy. This study investigated three haptic pedal designs, each with high and low intensities of feedback, in a rapid prototyping, paired comparison design. Twenty drivers took part, experiencing the systems in a high-fidelity driving simulator. Results suggested that drivers were best guided towards an “idealized” (most fuel efficient) gas pedal position by force feedback (where a driver feels a step change in gas pedal force) as opposed to stiffness feedback (where a driver feels a changing gas pedal firmness). In either case, high levels of force/stiffness feedback were preferred. Objective performance measures mirrored the subjective results. Whilst the short-term nature (brief system exposure) of this study led to difficulties in drawing longer-term conclusions, it would appear that force feedback haptics are better suited than stiffness feedback to augment an effective driver interface supporting “green” driving.

A Rule-Based Spatial Reasoning Approach for OpenStreetMap Data Quality Enrichment; Case Study of Routing and Navigation

Scipedia content — Thu, 28 Jan 2021 21:44:11 +0100

Finding relevant geospatial information is increasingly critical because of the growing volume of geospatial data available within the emerging “Big Data” era. Users are expecting that the availability of massive datasets will create more opportunities to uncover hidden information and answer more complex queries. This is especially the case with routing and navigation services where the ability to retrieve points of interest and landmarks make the routing service personalized, precise, and relevant. In this paper, we propose a new geospatial information approach that enables the retrieval of implicit information, i.e., geospatial entities that do not exist explicitly in the available source. We present an information broker that uses a rule-based spatial reasoning algorithm to detect topological relations. The information broker is embedded into a framework where annotations and mappings between OpenStreetMap data attributes and external resources, such as taxonomies, support the enrichment of queries to improve the ability of the system to retrieve information. Our method is tested with two case studies that leads to enriching the completeness of OpenStreetMap data with footway crossing points-of-interests as well as building entrances for routing and navigation purposes. It is concluded that the proposed approach can uncover implicit entities and contribute to extract required information from the existing datasets.

Document type: Article

Stackable vs autonomous cars for shared mobility systems: A preliminary performance evaluation

Scipedia content — Thu, 28 Jan 2021 21:37:50 +0100

Car sharing is one of the key elements of a Mobility-on-Demand system, but it still suffers from several shortcomings, the most significant of which is the fleet unbalance during the day. What is typically observed in car sharing systems, in fact, is a vehicle shortage in so-called hot spots (i.e., areas with high demand) and vehicle accumulation in cold spots, due to the patterns in people flows during the day. In this work, we overview the main approaches to vehicle redistribution based on the type of vehicles the car sharing fleet is composed of, and we evaluate their performance using a realistic car sharing demand derived for a suburban area around Lyon, France. The main result of this paper is that stackable vehicles can achieve a relocation performance close to that of autonomous vehicles, significantly improving over the no-relocation approach and over traditional relocation with standard cars.

Comment: Accepted at the MoD@ITSC2017 worksho

Impact of Electric Taxi Systems on Airport Apron Operations and Gate Congestion

Scipedia content — Thu, 28 Jan 2021 21:18:55 +0100

Growth in air traffic demand and increasing attention for environmental impact of the air travel industry and airports has spurred the innovation of the Electric Taxi System (ETS). The ETS incorporates an electric motor in the main or nose landing gear of an aircraft, powered by the auxiliary power unit (APU) of the aircraft. The system allows the aircraft to maneuver and taxi without the use of its main engines or a tow truck. Thereby, the ETS reduces fuel usage and the environmental impact during the taxi phase of flights. Additionally, the system aims to increase the gate pushback efficiency. The ETS eliminates the need for a tow truck during the pushback process as it allows for autonomous pushbacks. The studies performed on existing ETSs (the EGTS and theWheelTug systems) indicate that time can be saved with autonomous pushbacks using the ETS. KLM Royal Dutch Airlines and Amsterdam Airport Schiphol (AAS) have instigated research to investigate the impact and potential benefits of the implementation of the ETS. This Msc. thesis research work continues the exploration of the ETS’s impact at AAS by posing the following research question: What opportunities does the ETS offer for gate capacity and buffer utilization optimization, and what is the value of the impact of the ETS on apron operations at Amsterdam Airport Schiphol? Thus, the research attempts to draw light on the value of the ETS for operations in the apron environment. With increasing air traffic demand, the gate capacity at Schiphol Airport is nearing its maximum during the airport’s peak hours. Therefore, the potential gate capacity enhancement procedures enabled by the ETS are explored in detail in this research. Additionally, the value of the ETS for the overall apron environment is investigated. The reduction in the need for tow trucks due to the ETS implementation also provides benefits for the apron environment. The ETS presents the possibility for of two gate usage optimization concepts to be implemented more widely,namely; the dispatch towing concept and the pit stop concept. The gate planningmodels designed in this research explore the potential of the implementation of the pit stop and dispatch towing concepts at AAS. Initially, a gate planning model is designed to graphically present the narrow body gate and buffer plan in gantt chart format. In doing so the gate and buffer planning schedule for the busiest day at AAS in 2014 is visualized. The pit stop and dispatch towing concepts are then applied to the schedule where possible. From the visualization of the gate plans with and without the ETS enabled concepts, it can be concluded that the pit stop concept increases gate capacity at AAS by approximately six additionally aircraft on the busiest day at the airport in 2014. Furthermore, the dipatch towing concept increases gate planning efficiency and reduces ground arrival delays for six arriving aircraft on the busiest day at the airport in 2014. The gate planning model is subsequently expanded in order to explore the effect of increased traffic and delays on the gate planning at AAS, and the usage of pit stops and dispatch towing to help increase gate capacity and solve delay conflicts, respectively. From the extended model it becomes apparent that should the number of peak hour flights at AAS increase by 10%, and average of 25% of the additional flights can be scheduled at a gate using the pit stop concept. Should the number of peak hour flights double, an average of 8.8% of the additional peak hour flights (corresponding to 12 flights) can be scheduled using the pit stop concept. Furthermore, the model shows that, between 10% and 12% of the ground delays caused by delayed peak hour flights at the gates can be solved through the implementation of dispatch towing. This results in an average of 17.2minutes saved for nearly 50% of the arriving delayed flights. The gate planning models have indicated the potential of the pit stop and dispatch towing concepts enabled by the ETS for gate planning efficiency and capacity at AAS. However, the implementation of the ETS influences many key performance indicators (KPIs) of the apron area. In order to explore the value of the ETS on the apron area, a value model is developed. The value model is based on the value operations methodology (VOM). The value model qualitative assessment indicates that the ETS can enhance the safety, capacity, and efficiency of the airport apron environment, while reducing the costs and environmental impact of the apron area operations. The results of the models and the research performed can be further analyzed and developed by KLM and AAS in order to assist in the development of electric taxi systems and, eventually, enhance their competitive position within the aviation industry.

Direct and In-direct Effects of New High Speed Rail Service: an Empirical Analysis Using Japanese Mobile Phone Location Data

Scipedia content — Thu, 28 Jan 2021 21:08:11 +0100

The development of high-speed rail (HSR) is expected to significantly change the long- distance travel structure and transportation patterns. The changes are expected to be not only the increase in the number of tourists who use HSR service (direct effect), but also the change in the regional travel structures by encouraging the growth of several zones as network hubs (indirect effect). In this paper, a methodology to understand the change in the residential - travel destination zone matrix derived from mobile phone location data is proposed. The developed methodology is applied to determine the effect of the Hokuriku HSR on the nationwide long- distance travel patterns. The proposed methodology decomposed the matrix into two meaningful matrices, which can be understood as the direct and indirect effects of HSR. The decomposed results indicate the following three features of the HSR effects: First, the changes before and after the development of the Hokuriku HSR on the residential - travel destination zone matrix are mostly explained by two patterns of change by direct and indirect effect. Second, the direct numerical effects are less significant than the indirect effects. Third, the changes are asymmetric in direction in several zone pairs, because of the indirect effects.

RDA Geospatial Interest Group

Scipedia content — Thu, 28 Jan 2021 21:05:10 +0100

Exploring crowdsourcing information to predict traffic-related impacts

Scipedia content — Thu, 28 Jan 2021 21:04:44 +0100

Due to the increased public awareness on global climate change and other environmental problems, advanced strategies and tools are being developed and used to reduce the environmental impact of transport. The main objective of this paper is to explore the potential of using crowdsourcing information as an alternative or complementary source data to predict traffic-related impacts. Three main road connections to two important commercial areas in the city of Aveiro in Portugal, are examined. Driving patterns over different periods were collected using a probe vehicle equipped with a GNSS data logger and volumes of traffic were counted during different days of the week. The emissions estimation was based on the concept of Vehicle Specific Power (VSP), which has the capability to predict emissions during a trip often-according recorded second-by-second vehicle dynamics. Various tests were conducted in order to explore the potential correlations between these data sets and the information of a certain place’s busy times that are provided by Google Maps. The findings of the study prove the potential of crowdsourcing information and shows that ICT technologies can be used to estimate environmental and traffic-related impacts.

Charging Information Services for BEVs – Two Competing and Complementary Business Models

Scipedia content — Thu, 28 Jan 2021 21:03:32 +0100

This paper examines information services in association with charging services, and in particular players that offer information services related to charging service offerings from many different operators. It identifies two main types of business models through studying and comparing 25 European charging information service providers. For one type of players the paper analyses the network character and how this is related to the business model. Future implications of European integration, standardization and entry on the two business models, operator information-consolidator and community-based business models, are also discussed.

Traffic Flow Models for Road Network with Intersections

Scipedia content — Thu, 28 Jan 2021 20:56:00 +0100

Electrical energy wireless transfert: Application to electric roads

Scipedia content — Thu, 28 Jan 2021 20:50:58 +0100

International audience; The present paper focuses on wireless energy transfer mechanisms applied to urban electric vehicles. It describes the using conditions of a particular transformer without ferromagnetic core, supplied by a resonant inverter and loaded by mobile sources (catenaries with magnetic induction to power electric vehicles). The system consists of unconventional transformers with large air-gaps and a generator who supplies the transformer. The paper describes the theoretical model used for the numerical simulation (magnetic circuit, power converter, loads), and the measurements provided by our experimental platform (Tesla lab.). The transformer is supplied by a half-bridge series resonant converter. The transformer secondary coil is mobile compared to the primary, which is fixed on the road. This system is found in many industrial applications such as light automatic vehicles, tramways, etc. In this work we will show that the performance of a transformer without magnetic circuit can be equivalent to a standard transformer.

Infrastructure-based cooperative, connected and automated driving in a transition phase

Scipedia content — Thu, 28 Jan 2021 20:45:46 +0100

In the domain of ITS (Intelligent Transport Systems), automated road transport has received high attention from industry, authorities and the general public. The perspective is that infrastructure-based cooperative, connected and automated driving is an option for enhancing traffic safety, traffic efficiency and energy efficiency, and for increasing comfort. The project TransAID (Transition Areas for Infrastructure-Assisted Driving) targets the transition phases between different levels of automation, and, more specifically, investigates the areas (called "Transition Areas") where this will happen (Transition Areas). The project will develop and demonstrate traffic management procedures and protocols to enable smooth coexistence of automated, cooperative, connected (equipped) vehicles and conventional (non-equipped) vehicles, especially in Transition Areas, in an urban environment. The paper will present the TransAID concept, research method and an initial architecture for addressing this specific issue.

Analytical Investigation and Parametric Study of Lateral Impact Behavior of Pressurized Pipelines and Influence of Internal Pressure

Scipedia content — Thu, 28 Jan 2021 20:39:39 +0100

BSTRACTThis article provides a combined computational and analytical study to investigate the lateral impact behavior of pressurized pipelines and inspect all the parameters such as the outside diameter and internal pressure and evaluate how they affect such behavior. In this study, quartic polynomial functions are applied to formulate the maximum crushing force (Fmax), maximum permanent displacement (W), and absorbed energy (E) of the pressurized pipelines during the impact problem. The effects of the diameter and pressure on Fmax, W, and E are therefore illustrated through analyzing these functions. Response surfaces are also plotted based on the generated quartic polynomial functions and the quality (accuracy) of these functions are verified through several techniques.

Traceability of Marine LNG Bunkering Measurements

Scipedia content — Thu, 28 Jan 2021 20:34:51 +0100

Industrial use of liquefied natural gas (LNG) has a surprisingly long history. The first practical refrigeration system was built in 1873; the first commercial liquefaction plant was built in 1917. Over time two applications have been developed that are relevant to the current paper. The first involves storage of LNG to handle peak demand in pipeline systems, the process is identified as “peak shaving”. A second application is the transport of hydrocarbon fuel where gas pipelines are unavailable."/jats:p" "jats:p"Paper published with permission.

Lightweight Joint Simulation of Vehicular Mobility and Communication with LIMoSim

Scipedia content — Thu, 28 Jan 2021 20:32:25 +0100

The provision of reliable and efficient communication is a key requirement for the deployment of autonomous cars as well as for future Intelligent Transportation Systems (ITSs) in smart cities. Novel communications technologies will have to face highly-complex and extremely dynamic network topologies in a Vehicle-to-Everything (V2X)-context and will require the consideration of mobility information into decision processes for routing, handover and resource allocation. Consequently, researches and developers require simulation tools that are capable of providing realistic representations for both components as well as means for leveraging the convergence of mobility and communication. In this paper, we present a lightweight framework for the simulation of vehicular mobility, which has a communications-oriented perspective by design and is intended to be used in combination with a network simulator. In contrast to existing approaches, it works without requiring Interprocess Communication (IPC) using an integrated approach and is therefore able to reduce the complexity of simulation setups significantly. Since mobility and communication share the same codebase, it is able to model scenarios with a high level of interdependency between those two components. In a proof-of-concept study, we evaluate the proposed simulator in different example scenarios in an Long Term Evolution (LTE)-context using real-world map data.

Quantifying sources and types of smartwatch usage sessions

Scipedia content — Thu, 28 Jan 2021 20:20:34 +0100

We seek to quantify smartwatch use, and establish differences and similarities to smartphone use. Our analysis considers use traces from 307 users that include over 2.8 million notifications and 800,000 screen usage events, and we compare our findings to previous work that quantifies smartphone use. The results show that smartwatches are used more briefly and more frequently throughout the day, with half the sessions lasting less than 5 seconds. Interaction with notifications is similar across both types of devices, both in terms of response times and preferred application types. We also analyse the differences between our smartwatch dataset and a dataset aggregated from four previously conducted smartphone studies. The similarities and differences between smartwatch and smartphone use suggest effect on usage that go beyond differences in form factor.

An Optimal Preventive Maintenance Model for Natural Gas Transmission Pipelines

Scipedia content — Thu, 28 Jan 2021 20:09:02 +0100

A Critical Analysis of Travel Demand Estimation for New One-Way Carsharing Systems

Scipedia content — Thu, 28 Jan 2021 20:04:58 +0100

International audience; —Technologic advancements have contributed to the spread of sharing economy concepts, a developing phenomenon that favors the shift from private mobility to service-use (shared mobility). One-way carsharing is a most recent and popular kind of shared mobility, that is growing and developing rapidly in various forms. These systems are considered to have a transformative impact on future urban transportation. Despite all of the benefits that have been reported from the use of new one-way carsharing (e.g. Autonomous Mobility-on-Demand systems), their impacts on the mobility are not certain yet. This comes from the fact that in such services supply and demand influence each other in a significant way in short-, mid-, and long-term. Also service characteristics at the level of each vehicle strongly affect the demand. In this paper methods, paradigms, toolkits and platforms used in the literature for the demand estimation of the new one-way carsharing systems, as well as their potential drawbacks are discussed. A review of the literature reveals that despite the considerable number of studies related to balancing vehicle stocks across stations in one-way systems, the investigation about demand estimation of such services for which the complex relationship between supply and demand is considered, remain very limited. The majority of current platforms and toolkits used for demand estimation of new one-way carsharing systems are based on activity-based multi-agent simulations. In these simulations several main components are not yet taken into account, which could dramatically change the results. Data detail, accessibility and reliability, high computational time, calibration and validation still remain major challenges for travel demand estimation for one-way carsharing systems.

An App-based Algorithmic Approach for Harvesting Local and Renewable Energy Using Electric Vehicles

Scipedia content — Thu, 28 Jan 2021 20:03:06 +0100

The emergence of electric vehicles (EVs), combined with the rise of renewable energy production capacities, will strongly impact the way electricity is produced, distributed and consumed in the very near future. This position paper focuses on the problem of optimizing charging strategies for a fleet of EVs in the context where a significant amount of electricity is generated by (distributed) renewable energy. It exposes how a mobile application may offer an efficient solution for addressing this problem. This app can play two main roles. Firstly, it would incite and help people to play a more active role in the energy sector by allowing photovoltaic (PV) panel owners to sell their electrical production directly to consumers, here the EVs’ agents. Secondly, it would help distribution system operators (DSOs) or transmission system operators (TSOs) to modulate more efficiently the load by allowing them to influence EV charging behaviour in real time. Finally, the present paper advocates for the introduction of a two-sided market-type model between EV drivers and electricity producers. Peer reviewed

Active Image-based Modeling with a Toy Drone

Scipedia content — Thu, 28 Jan 2021 20:02:49 +0100

Image-based modeling techniques can now generate photo-realistic 3D models from images. But it is up to users to provide high quality images with good coverage and view overlap, which makes the data capturing process tedious and time consuming. We seek to automate data capturing for image-based modeling. The core of our system is an iterative linear method to solve the multi-view stereo (MVS) problem quickly and plan the Next-Best-View (NBV) effectively. Our fast MVS algorithm enables online model reconstruction and quality assessment to determine the NBVs on the fly. We test our system with a toy unmanned aerial vehicle (UAV) in simulated, indoor and outdoor experiments. Results show that our system improves the efficiency of data acquisition and ensures the completeness of the final model.

Comment: To be published on International Conference on Robotics and Automation 2018, Brisbane, Australia. Project Page: https://huangrui815.github.io/active-image-based-modeling/ The author's personal page: http://www.sfu.ca/~rha55

Delay Analysis of AVB traffic in Time-Sensitive Networks (TSN)

Scipedia content — Thu, 28 Jan 2021 19:57:40 +0100

International audience; Future autonomous vehicles and ADAS (Advanced Driver Assistance Systems) need real-time audio and video transmission together with control data traac (CDT). Audio/video stream delay analysis has been largely investigated in AVB (Audio Video Bridging) context, but not yet with the presence of the CDT in the new TSN context. In this paper we present a local delay analysis of AVB frames under hierarchical scheduling of credit-based shaping and time-aware shaping on TSN switches. We present the eeects of time aware shaping on AVB traac, how it changes the relative order of transmission of frames leading to bursts and worst case scenarios for lower priority streams. We also show that these bursts are upper-bounded by the Credit-Bases Shaper, hence the worst-case transmissions delay of a given stream is also upper-bounded. We present the analysis to compute the worst case delay for a frame, as well as the feasibility condition necessary for the analysis to be applied. Our methods (analysis and simulation) are applied to an automotive use case, which is deened within the Eurostars RETINA project, and where both control data traac and AVB traac must be guaranteed. CCS CONCEPTS • Computer systems organization →Embedded systems; • Networks →Network reliability;

Evaluation of Key Operational Constraints Affecting On-Demand Mobility for Aviation in the Los Angeles Basin: Ground Infrastructure, Air Traffic Control and Noise

Scipedia content — Thu, 28 Jan 2021 19:50:01 +0100

Relocation in car sharing systems with shared stackable vehicles: Modelling challenges and outlook

Scipedia content — Thu, 28 Jan 2021 19:47:50 +0100

Car sharing is expected to reduce traffic congestion and pollution in cities while at the same time improving accessibility to public transport. However, the most popular form of car sharing, one-way car sharing, still suffers from the vehicle unbalance problem. Innovative solutions to this issue rely on custom vehicles with stackable capabilities: customers or operators can drive a train of vehicles if necessary, thus efficiently bringing several cars from an area with few requests to an area with many requests. However, how to model a car sharing system with stackable vehicles is an open problem in the related literature. In this paper, we propose a queueing theoretical model to fill this gap, and we use this model to derive an upper-bound on user-based relocation capabilities. We also validate, for the first time in the related literature, legacy queueing theoretical models against a trace of real car sharing data. Finally, we present preliminary results about the impact, on car availability, of simple user-based relocation heuristics with stackable vehicles. Our results indicate that user-based relocation schemes that exploit vehicle stackability can significantly improve car availability at stations.

Comment: IEEE ITSC 2017: 20th International Conference on Intelligent Transportation Systems, Yokohama, Japan. October 16 - 19, 2017

Adarules: Learning rules for real-time road-traffic prediction

Scipedia content — Thu, 28 Jan 2021 19:47:09 +0100

Traffic management is being more important than ever, especially in overcrowded big cities with over-pollution problems and with new unprecedented mobility changes. In this scenario, road-traffic prediction plays a key role within Intelligent Transportation Systems, allowing traffic managers to be able to anticipate and take the proper decisions. This paper aims to analyze the situation in a commercial real-time prediction system with its current problems and limitations. We analyze issues related to the use of spatiotemporal information to reconstruct the traffic state. The analysis unveils the trade-off between simple parsimonious models and more complex models. Finally, we propose an enriched machine learning framework, Adarules, for the traffic state prediction in real-time facing the problem as continuously incoming data streams with all the commonly occurring problems in such volatile scenario, namely changes in the network infrastructure and demand, new detection stations or failure ones, among others. The framework is also able to infer automatically the most relevant features to our end-task, including the relationships within the road network, which we call as “structure learning”. Although the intention with the proposed framework is to evolve and grow with new incoming big data, however there is no limitation in starting to use it without any prior knowledge as it can starts learning the structure and parameters automatically from data. (Part of special issue: 20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest, Hungary)

Peer Reviewed

Task routing and assignment in crowdsourcing based on cognitive abilities

Scipedia content — Thu, 28 Jan 2021 19:44:54 +0100

Appropriate task routing and assignment is an important, but often overlooked, element in crowdsourcing research and practice. In this paper, we explore and evaluate a mechanism that can enable matching crowdsourcing tasks to suitable crowd-workers based on their cognitive abilities. We measure participants’ visual and fluency cognitive abilities with the well-established Kit of Factor-Referenced Cognitive Test, and measure crowdsourcing performance with our own set of developed tasks. Our results indicate that participants’ cognitive abilities correlate well with their crowdsourcing performance. We also built two predictive models (beta and linear regression) for crowdsourcing task performance based on the performance on cognitive tests as explanatory variables. The model results suggest that it is feasible to predict crowdsourcing performance based on cognitive abilities. Finally, we discuss the benefits and challenges of leveraging workers’ cognitive abilities to improve task routing and assignment in crowdsourcing environments.

Document type: Conference object

The research and realization of multi-platform real-time message-oriented middleware in large-scale air traffic control system

Scipedia content — Thu, 28 Jan 2021 19:41:14 +0100

Operating requirement of air traffic control system, the multi-platform real-time message-oriented middleware was studied and realized, which is composed of CDCC and CDCS. The former provides application process interface, while the latter realizes data synchronism of CDCC and data exchange. MQM, as one important part of it, provides message queue management and, encrypt and compress data during transmitting procedure. The practical system application verifies that the middleware can simplify the development of air traffic control system, enhance its stability, improve its systematic function and make it convenient for maintenance and reuse.

Performance evaluation of an on-board integrated battery charger system using a 12-Slot/10-pole surface-mounted PM propulsion motor

Scipedia content — Thu, 28 Jan 2021 19:39:06 +0100

The concept of Electric Vehicles (EVs) withonboard integrated battery chargers, which can be directly connected to the three-phase ac mains, has recently emerged as a cost effective and a practical alternative to charging stations. In such systems, the propulsion system power electronics are used to charge the battery, while, the stator winding of the propulsion motor is used to filter the charging current. This way, the need for separate bulky inductors typically used in battery charging converters is eliminated. Among the different configurations presented in the literature, those based on multiphase windings reduce the need for extra hardware components for winding reconfiguration to switch between propulsion and charging modes of operation. All systems provided in the literature are either based on induction or PM synchronous motors with distributed windings. In recent motor designs employed to EV, PM machines with Fractional Slot Concentrated Winding (FSCW) is much preferred. This paper investigates the effect of different operational modes of an on-board integrated battery charger on the torque ripple and the induced rotor eddy current loss caused by different MMF space harmonics associated with such FSCW type. The well-known 12-slot/10-pole PM machine is employed in this study and simulated using 2D finite element simulations. ? 2017 IEEE. This work was supported by a National Priorities Research (NPRP) grant from the Qatar National Research Fund (QNRF). Scopu

Electrical energy and mobility issues in Africa: Which complementarities?

Scipedia content — Thu, 28 Jan 2021 19:37:01 +0100

International audience; Africa is on the way of a long term development to give access to energy to all citizens wherever they live, either in urban or rural areas. The energy access is mandatory to accelerate the economic growth. Besides, African citizens also require a better access to mobility, both individual or collective. African countries also encourage initiatives for clean electricity generation and clean mobility. Thus, considering the innovative smart grids solutions that are already proposed or will be proposed in the future, electric mobility means could bring distributed energy storage capacities to the electrical grids. This could mainly be true in the case of islanding areas were photovoltaic generation will likely deliver the main part of electrical energy. The present paper aims at promoting the idea of a coupled approach for energy and mobility developments considering the storage capacities of electric vehicles or electric motorcycles.

A Schema of Possible Negative Effects of Advanced Driver Assistant Systems

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

The purpose of Advanced Driver Assistance Systems (ADAS) is to enhance traffic safety and efficiency. ADAS can be considered as a (still incomplete) collection of systems and subsystems towards a fully automated highway system, such as autonomous cars. However, as many researchers argue, in assessing the benefits of ADAS it has to be taken into account that any gains in terms of security may be again reduced by the fact they affect the drivers' behavior. In this paper, the authors introduce a schema of possible negative effects of advanced driver assistant systems according to which consequences of a system failure largely depend on the magnitude of over-reliance. Based on that schema, they itemize hypotheses on possible behavioral effects of a specific ADAS type, namely local danger alerts.

BURIED PIPELINES SUBJECTED TO GROUND DEFORMATION CAUSED BY LANDSLIDE TRIGGERING

Scipedia content — Thu, 28 Jan 2021 19:24:36 +0100

Simulation of V2V Blind Corner Communication Using Measured Vehicular Antenna Pattern

Scipedia content — Thu, 28 Jan 2021 19:23:57 +0100

Mobile communication for vehicles is a promising technology to increase road safety and traffic efficiency. Advanced driver assistance systems (ADAS) basing on mobile communication have to be validated properly before being deployed in commercial vehicles. Basing on an existing test facility, we have set up an urban intersection aiming to reproduce real world propagation effects. In recent studies, requirements for the building properties were derived in simulations assuming an omnidirectional radiator on the vehicle rooftop for a vehicle-to-vehicle (V2V) blind corner communication. In this paper, a measured radiation pattern of an antenna mounted on a vehicle's rooftop is used for the investigation of wave propagation and compared to the omnidirectional radiator. The measured vehicular antenna is mainly radiating in the upper hemisphere. The horizontal cut shows some distinct nulls and especially in the front half of the car two symmetric lobes. In spite of the large differences in the radiation patterns, the simulations results of wave propagation for the measured antenna pattern are similar to the omnidirectional antenna due to multiple reflections from the surrounding building walls and the roadway.

Real-time Identification of Guidance Modes in Aircraft Descents Using Surveillace Data

Scipedia content — Thu, 28 Jan 2021 19:12:59 +0100

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

37th DASC Best student paper award,2018; premi al millor article de la conferència on el primer autor és un estudiant, atorgat per l'Institute of Electrical and Electronics Engineers

Trajectory predictors require information on the flight-intent in order to estimate the future state of the aircraft. At present, however, such information is not available or it is very limited and coarse (unless predicting the ownship trajectory). In this paper, an interacting multiple-model (IMM) algorithm is proposed to improve the accuracy of short-term trajectory predictions. The active guidance mode of an aircraft is estimated in real-time observing flight data collected only from automatic dependent surveillance-Broadcast (ADS-B) and transponder selective mode (Mode S) emissions. The algorithm is set up with different models corresponding to the most typical guidance modes, and provides the model that better fits the observations. The proposed algorithm is validated by means of two simulated trajectories whose guidance modes were known beforehand. Finally, the performance of the algorithm with real flight data is demonstrated through a detailed example. Promising results are obtained, showing that the active guidance mode can be unequivocally identified with a negligible delay.

Peer Reviewed

Award-winning

Document type: Conference object

Evaluation of a semi-autonomous lane departure correction system using naturalistic driving data

Scipedia content — Thu, 28 Jan 2021 19:12:30 +0100

Evaluating the effectiveness and benefits of driver assistance systems is essential for improving the system performance. In this paper, we propose an efficient evaluation method for a semi-autonomous lane departure correction system. To achieve this, we apply a bounded Gaussian mixture model to describe drivers' stochastic lane departure behavior learned from naturalistic driving data, which can regenerate departure behaviors to evaluate the lane departure correction system. In the stochastic lane departure model, we conduct a dimension reduction to reduce the computation cost. Finally, to show the advantages of our proposed evaluation approach, we compare steering systems with and without lane departure assistance based on the stochastic lane departure model. The simulation results show that the proposed method can effectively evaluate the lane departure correction system.

Comment: arXiv admin note: text overlap with arXiv:1702.05779

Adaptive Traffic Signal Control : Exploring Reward Definition For Reinforcement Learning

Scipedia content — Thu, 28 Jan 2021 19:09:36 +0100

International audience; As mobility grow in urban cities, traffic congestion become more frequent and troublesome. traffic signal is one way to decrease traffic congestion in urban areas but needs to be adjusted in order to take into account the stochasticity of traffic. Reinforcement learning (RL) has been the object of investigation of many recent papers as a promising approach to control such a stochastic environment. The goal of this paper is to analyze the feasibility of RL, particularly the use of Q-learning algorithm for adaptive traffic signal control in different traffic dynamics. A RL control was developed for an isolated multi-phase intersection using a microscopic traffic simulator known as Paramics. The novelty of this work consists of its methodology which uses a new generalized state space with different known reward definitions. The results of this study demonstrate the advantage of using RL over fixed signal plan, and yet exhibit different outcomes depending on the reward definitions and different traffic dynamics being considered.

Design of a Mobile-Internet-Based Management Platform for Materials Transportation of Road and Bridge Engineering

Scipedia content — Thu, 28 Jan 2021 19:08:39 +0100

Application of GPS sensor for recovery of precise position of aircraft in air transport

Scipedia content — Thu, 28 Jan 2021 19:08:09 +0100

Bayesian calibration of mechanical parameters of high-speed train suspensions

Scipedia content — Thu, 28 Jan 2021 19:06:04 +0100

International audience; The objective of the work presented here is a bayesian calibration of parameters describing the mechanical characteristics of high-speed train suspensions for maintenance purposes. This calibration is achieved by comparing simulation results to on-track accelerometric measurements. It requires the estimation on the multidimensionnal admissible set of the parameters of the likelihood function of the train dynamic response. This estimation is achieved thanks to the identification of a kriging metamodel of this likelihood function to reduce the numerical cost. From this metamodel, the posterior probability density function of the parameters is estimated using an MCMC algorithm.

MOBILE TRAFFIC ALERT AND TOURIST ROUTE GUIDANCE SYSTEM DESIGN USING GEOSPATIAL DATA

Scipedia content — Thu, 28 Jan 2021 19:03:05 +0100

Bhattacharya, D., Painho, M., Mishra, S., & Gupta, A. (2017). Mobile traffic alert and tourist route guidance system design using geospatial data. In International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives (Vol. 42, pp. 11-18). (ISPRS Archives; Vol. 42, No. 4W3). https://doi.org/10.5194/isprs-archives-XLII-4-W3-11-2017 The present study describes an integrated system for traffic data collection and alert warning. Geographical information based decision making related to traffic destinations and routes is proposed through the design. The system includes a geospatial database having profile relating to a user of a mobile device. The processing and understanding of scanned maps, other digital data input leads to route guidance. The system includes a server configured to receive traffic information relating to a route and location information relating to the mobile device. Server is configured to send a traffic alert to the mobile device when the traffic information and the location information indicate that the mobile device is traveling toward traffic congestion. Proposed system has geospatial and mobile data sets pertaining to Bangalore city in India. It is envisaged to be helpful for touristic purposes as a route guidance and alert relaying information system to tourists for proximity to sites worth seeing in a city they have entered into. The system is modular in architecture and the novelty lies in integration of different modules carrying different technologies for a complete traffic information system. Generic information processing and delivery system has been tested to be functional and speedy under test geospatial domains. In a restricted prototype model with geo-referenced route data required information has been delivered correctly over sustained trials to designated cell numbers, with average time frame of 27.5 seconds, maximum 50 and minimum 5 seconds. Traffic geo-data set trials testing is underway. publishersversion published

Document type: Article

Innovation in the ICT Infrastructure as a Key Factor in Enhancing Road Safety: A Multi-sectoral Approach

Scipedia content — Thu, 28 Jan 2021 18:58:36 +0100

The ITSs (Intelligent Transportation Systems) are part of the ICT infrastructure and are built taking into account numerous legal and organisational conditions and individual needs of the users. They are the answer for wide requirements due to implementation of innovations in road transport. The primary objective of using ITSs is to improve the efficiency of traffic and traffic safety. The aim of this paper is to present a technical approach aiming to model the impact of environmental conditions such as urban traffic, visibility, other weather conditions and road conditions on road traffic safety, using the fuzzy logic and trying to explain also the economic and legal determinants of road safety as "non technical" parts.

Youthmappers: A Global Network To Empower Students In Mapping The World

Scipedia content — Thu, 28 Jan 2021 18:55:15 +0100

OpenStreetMap (OSM) is an openly-licensed geospatial database created and edited by millions of volunteers worldwide. This database is used in various humanitarian projects, such as mapping during disaster relief operations or malaria elimination campaigns. In some parts of the world, for example certain areas in Mozambique, no official cartographic data is available and hence OSM can play a crucial role. A mapathon (literally “map marathon”) is a collaborative effect that is an effective method of collecting map data in unmapped areas. Through the YouthMappers global initiative (http://www.youthmappers.org), students are actively engaging in OSM-based collaborative mapping efforts internationally. We will briefly discuss the process followed by three YouthMappers chapters; Politecnico di Milano (Italy), Texas Tech University (United States of America), and University of Pretoria (South Africa), and lessons learned. In Milano, students’ mapathons are organized monthly and they are focused either on field-mapping (e.g. to improve the OSM map of the university) or remote mapping on humanitarian tasks; learning sessions on OSM editing tools are also held periodically. In Texas, students organize mapathons several times per year, and they can take a dedicated service-learning course for credit where they work on teams with other students around the world to map the same areas and research the humanitarian or development issue affecting the region. In Pretoria, monthly mapathons are held and each mapathon focusses on a different area. Extra credits are offered to encourage participation. From our experiences, it became evident that even though OSM tools are user-friendly, students do need some training, and a short training video as part of the introduction presentation was developed. Additionally, understanding the purpose for a mapathon in an area, motivates and encourage active participation and ensures that quality data is captured. Internationally students participate and learn from other YouthMappers chapters through regular organized web conferences. In conclusion, incorporating mapathons into the curriculum encourages students to contribute needed data required for humanitarian projects. Simultaneously, students get practical experience in data capturing and awareness is raised of humanitarian challenges in other parts of the world.

The Impact of Population Growth on the Future Air Traffic Demand in Singapore

Scipedia content — Thu, 28 Jan 2021 18:53:05 +0100

Manipulating the five V's in the next generation air transportation system

Scipedia content — Thu, 28 Jan 2021 18:50:12 +0100

The U.S. Next Generation Air Transportation System (NextGen) is designed to increase the capacity, safety and efficiency of the air traffic control via the integration of past experiences and advances in technology. However, the system is expected to greatly increase the amount and types of data generated as well as the knowledge to be managed. Additionally, as with all new technology, U.S. NextGen opens the specter of the potential impacts created by cyberattacks. Given this, it appears logical to view the U.S. NextGen system from the lens of Big Data. This study evaluates the U.S. NextGen system using the five differentiated qualitative characteristics of big data: Volume, Velocity, Variety, Veracity and Value. The results indicate that U.S. NextGen system has several big data challenges that must be addressed in order to obtain its maximal potential. Refereed/Peer-reviewed

Safety analysis of passing maneuvers using extreme value theory

Scipedia content — Thu, 28 Jan 2021 18:47:45 +0100

The increased availability of detailed trajectory data sets from naturalistic, observational, and simulation-based studies, is a key source for potential improvements in the development of detailed safety models that explicitly account for vehicle conflict interactions and various driving maneuvers. Despite the well-recognized research findings on both crash frequency estimation and traffic conflict analysis carried out over the last decades, only recently researchers have started to study and model the link between the two. This link is typically made by statistical association between aggregated conflicts and crashes, which still relies on crash data and ignores heterogeneity in the estimation procedure. More recently, an extreme value (EV) approach has been used to link the probability of a crash occurrence to the frequency of conflicts estimated from observed variability of crash proximity, using a probabilistic framework and without using crash records. In this study the Generalized Extreme Value distribution used in the block maxima (BM) approach and the Generalized Pareto Distribution used in the peak over threshold approach (POT), are tested and compared for the estimation of head-on collisions in passing maneuvers. The minimum time-to-collision with the opposite vehicle is used in both EV methods. Detailed trajectory data of the passing, passed and opposite vehicles from a fixed-based driving simulator experiment was used in this study. One hundred experienced drivers from different demographic strata participated in this experiment on a voluntary basis. Several two-lane rural highway layouts and traffic conditions were considered in the design of the driving simulator scenarios. Raw data was collected at a resolution of 0.1 s and included the longitudinal and lateral positions, speeds and accelerations of all vehicles in the scenario. From this raw data, both methods were tested for stationary and non-stationary models. The latter allowed not-only for a better modeling performance in estimating the number of expected crashes, but also for a quantified analysis of the detailed driving choices affecting the head-on crash probability during passing maneuvers. The estimation results showed that the BM approach yielded more stable results compared to the POT approach, but the latter was able to produce crash rate estimates more consistently sensitive to the covariates of interest. Finally, the estimated distributions were validated using a second set of data extracted from an additional driving simulator experiment. The results indicate that this is a promising approach for safety evaluation. On-going work of the authors will attempt to generalize this method to other safety measures related to passing maneuvers, test it for the detailed analysis of the effect of demographic factors on passing maneuvers' crash probability and for its usefulness in a traffic simulation environment.

Automated planning for urban traffic management

Scipedia content — Thu, 28 Jan 2021 18:45:42 +0100

The global growth in urbanisation increases the demand for services including road transport infrastructure, presenting challenges in terms of mobility. Optimising the exploitation of urban road network, while attempting to minimise the effects of traffic emissions, is a great challenge. SimplyfAI was a UK research council grant funded project which was aimed towards solving air quality problems caused by road traffic emissions. Large cities such as Manchester struggle to meet air quality limits as the range of available traffic management devices is limited. In the study, we investigated the application of linked data to enrich environmental and traffic data feeds, and we used this with automated planning tools to enable traffic to be managed at a region level. The management will have the aim of avoiding air pollution problems before they occur. This demo focuses on the planning component, and in particular the engineering and validation aspects, that were pivotal for the success of the project.

Model identification for thermal modelling of a battery pack

Scipedia content — Thu, 28 Jan 2021 18:44:06 +0100

Thermal pack management is dependent on the duty cycle and vehicle use. Thermal modelling of the pack for design, as well as active measures in operation to reduce thermal loads during operation can greatly improve the lifetime of the pack. Advances in state estimation, measurement techniques and control are coupled with the system design; and both are dependent on representative models. As the cells age, the thermal behaviour will change, and therefore a robust control technique and in-situ thermal model identification is often required. This paper focuses on methodologies towards thermal characterization of cell models and of a pack as a whole.

Robust Solution Approach for the Dynamic and Stochastic Vehicle Routing Problem

Scipedia content — Thu, 28 Jan 2021 18:43:24 +0100

The dynamic and stochastic vehicle routing problem (DSVRP) can be modelled as a stochastic program (SP). In a two-stage SP with recourse model, the first stage minimizes the a priori routing plan cost and the second stage minimizes the cost of corrective actions, performed to deal with changes in the inputs. To deal with the problem, approaches based either on stochastic modelling or on sampling can be applied. Sampling-based methods incorporate stochastic knowledge by generating scenarios set on realizations drawn from distributions. In this paper we proposed a robust solution approach for the capacitated DSVRP based on sampling strategies. We formulated the problem as a two-stage stochastic program model with recourse. In the first stage the a priori routing plan cost is minimized, whereas in the second stage the average of higher moments for the recourse cost calculated via a set of scenarios is minimized. The idea is to include higher moments in the second stage aiming to compute a robust a priori routing plan that minimizes transportation costs while permitting small changes in the demands without changing solution structure. Additionally, the approach allows managers to choose between optimality and robustness, that is, transportation costs and reconfiguration. The computational results on a generic dynamic benchmark dataset show that the robust routing plan can cover unmet demand while incurring little extra costs as compared to the preplanning. We observed that the plan of routes is more robust; that is, not only the expected real cost, but also the increment within the planned cost is lower.

Document type: Article

Incident detection using data from social media

Scipedia content — Thu, 28 Jan 2021 18:38:25 +0100

Due to the rapid growth of population in the last 20 years, an increased number of instances of heavy recurrent traffic congestion has been observed in cities around the world. This rise in traffic has led to greater numbers of traffic incidents and subsequent growth of non-recurrent congestion. Existing incident detection techniques are limited to the use of sensors in the transportation network. In this paper, we analyze the potential of Twitter for supporting real-time incident detection in the United Kingdom (UK). We present a methodology for retrieving, processing, and classifying public tweets by combining Natural Language Processing (NLP) techniques with a Support Vector Machine algorithm (SVM) for text classification. Our approach can detect traffic related tweets with an accuracy of 88.27%.

Study of a complete free route airspace implementation in the european airspace

Scipedia content — Thu, 28 Jan 2021 18:37:30 +0100

Free route airspace permits users to freely plan a route between defined entry and exit waypoints, with the possibility of routing via intermediate points. Flights flying in a free route area remain subject to air traffic control (ATC) for separation provision. This research evaluates an extreme future scenario of free route implementation across Europe. We consider the complete upper airspace of the European Civil Aviation Conference (ECAC) area as a unique airspace block configured with free route. The paper is centered in investigating the benefits for the airspace users, and in the study of possible increments of complexity of such configuration. In this research, fast time simulations are carrying out to discover how much flight time, fuel and distance aircraft can save with this free route configuration. In the other side, the paper explains the evolution of conflicts derived from potential separation losses between aircraft in this new environment. Separation losses in free route can emerge at any point of the airspace, which can require greater effort for solving them in comparison with fixed airways configuration, where conflicts are usually found in well-known airways intersections. The airspace configurations modelled in this study are the fixed airways structure, named as Current, and the future scenario, named as EUROFRA, where new navigation points are added. This research studies the advantages and difficulties that a large scale application of the free route concept can bring to the European airspace.

Peer Reviewed

A NEAT framework for application-awareness in SDN environments

Scipedia content — Thu, 28 Jan 2021 18:32:06 +0100

Software-Defined Networking (SDN) has led to a paradigm shift in the way how networks are managed and operated. In SDN environments the data plane forwarding rules are managed by logically centralized controllers operating on global view of the network. Today, SDN controllers typically posses little insight about the requirements of the applications executed on the end-hosts. Consequently, they rely on heuristics to implement traffic engineering or QoS support. In this work, we propose a framework for application-awareness in SDN environments where the end-hosts provide a generic interface for the SDN controllers to interact with. As a result, SDN controllers may enhance the end-host’s view of the attached network and deploy policies into the edge of the network. Further, controllers may obtain information about the specific requirements of the deployed applications. Our demonstration extends the OpenDaylight SDN controller to enable it to interact with end-hosts running a novel networking stack called NEAT. We demonstrate a scenario in which the controller distributes policies and path information to manage bulk and low-latency flows. "p"Demo paper"/p" NEAT

Path assignment techniques for vehicle tracking

Scipedia content — Thu, 28 Jan 2021 18:31:26 +0100

Many driver assistance systems such as Adaptive Cruise Control require the identification of the closest vehicle that is in the host vehicle's path. This entails an assignment of detected vehicles to the host vehicle path or neighboring paths. After reviewing approaches to the estimation of the host vehicle path and lane assignment techniques we introduce two methods that are motivated by the rationale to filter measured data as late in the processing stages as possible in order to avoid delays and other artifacts of intermediate filters. These filters generate discrete posterior probability distributions from which a path or "lane" index is extracted by a median estimator. The relative performance of those methods is illustrated by a ROC using experimental data and labeled ground truth data.

Comment: 6 pages, 9 figure

Electric vehicle use in public fleets: The case of the Genoa University

Scipedia content — Thu, 28 Jan 2021 18:30:29 +0100

Electric mobility is assuming a central role in the new world energy scenario where Renewable Energy Sources (RES) have increased their contribution to the electricity production, mainly due to the fact they are characterized by a reduced environmental impact; in the aforesaid context, Electric Vehicles (EVs) can play a significant role to facilitate the integration of RES into the power grid, also within smart grid infrastructures. Public administration represents one of the sectors that can mostly benefit from the use of the EV technology in its fleets; in many countries, governments have introduced incentive policies to support the spread of the electric mobility and car manufacturers are developing EVs for urban transportation users. In this paper, the attention is focused on a smart microgrid project developed at the University of Genoa and based on the integration of RES, EVs and storage systems. In particular, the attention is here pointed on the use of the EVs to highlight the different habits of recharge adopted at the Genoa University. The paper describes the smart microgrid test-bed facility at the Savona Campus and reports the most significant results relative to an experimental campaign conducted on EVs.

Digital reality for production and MRO innovations: Presentation held at Fraunhofer Aviation Conference, 25. April 2018, EXPO Center Airport, Berlin

Scipedia content — Thu, 28 Jan 2021 18:29:13 +0100

Enabling Airspace Integration for High-Density On-Demand Mobility Operations

Scipedia content — Thu, 28 Jan 2021 18:22:50 +0100

Response Accuracy and Tracking Errors with Decentralized Control of Commercial V2G Chargers

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

There is a growing interest in using the flexibility of electric vehicles (EVs) to provide power system services, such as fast frequency regulation. Decentralized control is advocated due to its reliability and much lower communication requirements. A commonly used linear droop characteristic results in low average efficiencies, whereas controllers with 3 modes (idle, fully charging, fully discharging) result in large reserve errors when the aggregation size is small. To address these issues, we propose a stochastic, decentralized controller with tunable response granularity which minimizes switching actions. The EV fleet operator can optimize the chargers’ performance according to the fleet size, the service error requirements, the average switching rate and the average efficiency. We use real efficiency characteristics from EVs and chargers providing fast frequency regulation and we show that the proposed controller can significantly reduce reserve errors and increase efficiency for a given fleet size, while at the same time minimizing the switching actions."br

Analysis of an efficient on-chip servo-loop technique for reduced-code static linearity test of pipeline ADCs

Scipedia content — Thu, 28 Jan 2021 18:18:35 +0100

International audience; This work presents an efficient modification of the classical servo-loop static test setup aimed at the on-chip imple- mentation of reduced-code static linearity test techniques. The proposed modified servo-loop provides a direct measurement of the width of a given ADC code without the need of an integrated voltmeter. The proposed measurement strategy is based on using a controlled step-wise ramp stimulus generator for exciting the ADC under test in such a way that the measurement of a code width can be determined in the digital domain by simply counting the number of ramp steps between two consecutive ADC output transitions. Moreover, the ability of the proposed servo-loop to target a given ADC code makes it very suitable for implementing advanced reduced-code static test techniques. This work analyses the performance limits of the proposed discrete-time servo-loop technique and explores its application to reduced-code linearity testing of pipeline ADCs.

Governing Urban Mobility. Strong Urban Governance for Liveable Cities

Scipedia content — Thu, 28 Jan 2021 18:16:53 +0100

Produced with the support of EUROCITIES as part of the CREATE (Congestion Reduction in Europe, Advancing Transport Efficiency) project, WP4 "Qualitative analysis of historical transport policy developments across 5 EU capital-cities".; International audience; Why have some cities in Europe been able to achieve a shift from the car-oriented city towards more sustainable modes of transport? How can other parts of Europe and the EuroMed draw lessons from CREATE?In order to answer these fundamental questions, the CREATE (Congestion Reduction in Europe, Advancing Transport Efficiency) project’s main objective is to reduce road congestion in European cities by encouraging a switch from cars to more sustainable modes of transport. Among other valuable lessons, the CREATE project shows how strong urban governance contributes to the shift towards the liveable city.

The use of synthetic vision tools in the control tower environment : the RETINA concept

Scipedia content — Thu, 28 Jan 2021 18:11:14 +0100

The Resilient Synthetic Vision for Advanced Control Tower Air Navigation Service Provision (RETINA) project is one of the selected Single European Sky ATM Research (SESAR) exploratory research projects on High Performing Airport Operations and it investigates the potential and applicability of Virtual/Augmented Reality (V/AR) technologies for the provision of Air Traffic Control (ATC) service by the airport control tower. The project assesses whether those concepts that stand behind tools such as Head-Mounted Displays (HUDs), Enhanced Vision Systems (EVSs) and Synthetic Vision Systems (SVS) can be transferred to ATC with relatively low effort and substantial benefits for controllers' Situational Awareness (SA). In doing so, two different augmented reality systems are investigated: Spatial Displays (SD) that, potentially, can be made to coincide with the tower windows and See-Through Head-Mounted Displays (ST-HMD). In this context the RETINA concept will enable the Air Traffic Controller to have a head-up view of the airport traffic even in low visibility conditions, similar to the vision currently provided in the cockpit with Head-Up displays. In the two-year project, the RETINA concept was developed, implemented and validated by means of human-in-the-loop simulations where the external view is provided to the user through a high fidelity 3D digital model in an immersive environment.

A comprehensive approach for validation of air traffic management security prototypes: A case study

Scipedia content — Thu, 28 Jan 2021 18:05:14 +0100

Security in air traffic management is still a rather new challenge and receives increased interest during recent years. This implies that new security concepts and systems are developed. Usually all systems have to go through several validation cycles to reach a higher technical readiness level. As no well-established validation approach is available which considers the special aspects of security this forms an additional barrier when developing air traffic control security systems. This is true because suitable validation approaches have to be developed first. The latter includes the risk of forgetting something, when the development is not initiated in a structured way. Within the air traffic security project GAMMA such an approach has been developed and applied to a set of seven prototypes. Based on the European Operational Concept Validation Methodology and a Security Risk Assessment Methodology, this approach identifies additional security controls, system requirements, validation objectives and key performance indicators. These are the driving elements for the design of the validation setup and procedure The paper demonstrates the feasibility of this new approach using one specific example, the Secure Air Traffic Control Communications prototype. The paper describes the approach and the resulting validation setup and procedures in detail. It briefly describes the obtained results for the developed prototype as one specific use case of the approach.

An on-line monitoring system for navigation equipment

Scipedia content — Thu, 28 Jan 2021 18:02:37 +0100

Civil air navigation equipment is the most important infrastructure of Civil Aviation, which is closely related to flight safety. In addition to regular flight inspection, navigation equipment’s patrol measuring, maintenance measuring, running measuring under special weather conditions are the important means of ensuring aviation flight safety. According to the safety maintenance requirements of Civil Aviation Air Traffic Control navigation equipment, this paper developed one on-line monitoring system with independent intellectual property rights for navigation equipment, the system breakthroughs the key technologies of measuring navigation equipment on-line including Instrument Landing System (ILS) and VHF Omni-directional Range (VOR), which also meets the requirements of navigation equipment ground measurement set by the ICAO DOC 8071, it provides technical means of the ground on-line measurement for navigation equipment, improves the safety of navigation equipment operation, and reduces the impact of m...

Exploring Perception of Vibrations from Rail: An Interview Study

Scipedia content — Thu, 28 Jan 2021 18:01:04 +0100

Rail transport is an environmentally responsible approach and traffic is expected to increase in the coming decades. Little is known about the implications for quality of life of populations living close to railways. This study explores the way in which vibrations from rail are perceived and described by these populations. The study took place in the Vastra Gotaland and Varmland regions of Sweden. A qualitative study approach was undertaken using semi-structured interviews within a framework of predetermined questions in participants’ homes. A 26.3% response rate was achieved and 17 participants were interviewed. The experience of vibrations was described in tangible terms through different senses. Important emerging themes included habituation to and acceptance of vibrations, worry about property damage, worry about family members and general safety. Participants did not reflect on health effects, however, chronic exposure to vibrations through multimodal senses in individual living environments may reduce the possibility for restoration in the home. Lack of empowerment to reduce exposure to vibrations was important. This may alter individual coping strategies, as taking actions to avoid the stressor is not possible. The adoption of other strategies, such as avoidance, may negatively affect an individual’s ability to cope with the stressor and their health.

Document type: Article

Accurate Optical Flow via Direct Cost Volume Processing

Scipedia content — Thu, 28 Jan 2021 17:59:51 +0100

We present an optical flow estimation approach that operates on the full four-dimensional cost volume. This direct approach shares the structural benefits of leading stereo matching pipelines, which are known to yield high accuracy. To this day, such approaches have been considered impractical due to the size of the cost volume. We show that the full four-dimensional cost volume can be constructed in a fraction of a second due to its regularity. We then exploit this regularity further by adapting semi-global matching to the four-dimensional setting. This yields a pipeline that achieves significantly higher accuracy than state-of-the-art optical flow methods while being faster than most. Our approach outperforms all published general-purpose optical flow methods on both Sintel and KITTI 2015 benchmarks.

Comment: Published at the Conference on Computer Vision and Pattern Recognition (CVPR 2017)

Ecodrive Training Delivers Substantial Fuel Savings for Heavy Vehicle Drivers

Scipedia content — Thu, 28 Jan 2021 17:55:20 +0100

The concept of ecodriving has been in existence for at least 15 years, and its use has been widespread in Europe. In the UK more than 12,000 heavy vehicle drivers have received training from one scheme alone, with fuel savings of the order of 10% (SAFED, 2007). The primary thrust of ecodriving is a smoother driving style – ‘gliding’ or ‘flowing’ through traffic – with the principal aim of reducing fuel consumption and emissions. These savings are realised with behaviours that include shifting up through the gears as soon as possible and skipping gears when appropriate, maintaining a steady speed in the highest gear possible, and maintaining appropriate tyre pressures and servicing schedules. It is also critical to avoid heavy and/or sudden acceleration or braking and to look as far ahead down the traffic stream as possible in order to anticipate the actions of other drivers and predict likely changes and interruptions to the traffic flow. This more defensive or anticipatory driving style should also serve to reduce the likelihood of being involved in a crash. A small group of heavy vehicle drivers underwent an ecodrive training course. Their driving was assessed for various ecodrive variables as they completed an 18 mile circuit in normal traffic immediately after the course and again 6 and 12 weeks later. Compared to pre-course measures, these drivers reduced their fuel consumption by an average of 27%, the number of gear changes by 29%, and the number of brake applications by 41%, though not all differences were statistically significant due to the size of this pilot and large driver variability. Importantly, the improvements were not offset by increases in the time taken to complete the circuit. At the 6 week point a control group was also assessed, and they used more fuel and more gear changes, and applied their brakes more often than the control group. Safety variables were inconclusive. A larger, in-service trial is warranted.

Cost-Benefit Analysis of Electric Bus Fleet with Various Operation Intervals

Scipedia content — Thu, 28 Jan 2021 17:54:24 +0100

Electric buses are particularly suitable for city and suburban routes due to zero local exhaust and noise emissions. The operation schedule interval defines the charging power, bus fleet size and total cost of ownership of a bus. We propose a novel cost-benefit method for the scheduling of an electric city bus fleet on a single route. Three different charging infrastructure scenarios were considered. In the first scenario, only one charging station was used. The second scenario considered two charging stations that were located at the same terminus. In the third scenario, two charging stations were located at opposite terminuses. The costs and utilization rates of the buses were analyzed with operation intervals up to 40 minutes. The first scenario with a single charging station had the lowest costs for the entire bus fleet system when the utilization rate was considered. Furthermore, the results show that certain schedule intervals are more cost-beneficial in terms of vehicle specific life-cycle costs than others. In the future, the proposed method is expanded to aid the design of bus network scheduling under energy demand uncertainty. Peer reviewed

Enhanced Indicators to Monitor ATM Performance in Europe. Main findings of the APACHE SESAR Exploratory Research project.

Scipedia content — Thu, 28 Jan 2021 17:48:29 +0100

This paper highlights the principal contributions and outcomes of the APACHE Project (a SESAR 2020 exploratory research project) in air traffic management performance assessment for monitoring purposes (post-ops analysis). Novel distance- and fuel-based indicators are proposed to assess environmental impact inefficiencies, taking as input only surveillance data sets. Similarly, novel cost- and trip-time-based indicators are proposed to assess airspace user cost-efficiency. In both cases, optimal trajectories are generated as baselines for these indicators, which are compared with actual (historical) trajectories. Regarding air navigation services cost-efficiency, a similar strategy is presented, where optimal sectorisations are compared with historical sectorisations. The paper also presents new indicators to assess safety from surveillance data in an automated fashion. A couple of indicators to better estimate system capacity are also given, which look at air traffic management delay as proxy. Finally, some illustrative examples are given to show the applicability of all these indicators.

Peer Reviewed

Mathematical modeling in the airline industry: optimizing aircraft assignment for on-demand air transport

Scipedia content — Thu, 28 Jan 2021 17:44:02 +0100

This paper addresses a problem faced by air companies that offer on-demand flight services. Given a list of flight requests, the company has to assign its aircrafts to these requests, so that operational costs are minimized. The main issue in this planning process regards the repositioning of aircrafts when they are not available at the airports of customer departure. The cost of this repositioning should be the least possible, as customers pay proportionally to their requested flights only. We propose an optimization model to support decision making in these situations. Computational experiments with real-life data provided by an on-demand air transport company indicate that the proposed model is appropriate and may significantly reduce the time spent on repositioning flights.

Towards Video Flow Classification at a Million Encrypted Flows Per Second

Scipedia content — Thu, 28 Jan 2021 17:41:45 +0100

end-to-end encryption on the Internet is becoming more prevalent, techniques such as deep packet inspection (DPI) can no longer be expected to be able to classify traffic. In many cellular networks a large fraction of all traffic is video traffic, and being able to divide flows in the network into video and non-video can provide considerable traffic engineering benefits. In this study we examine machine learning based flow classification using features that are available also for encrypted flows. Using a data set of several several billion packets from a live cellular network we examine the obtainable classification performance for two different ensemble-based classifiers. Further, we contrast the classification performance of a statistical-based feature set with a less computationally demanding alternate feature set. To also examine the runtime aspects of the problem, we export the trained models and use a tailor-made C implementation to evaluate the runtime performance. The results quantify the trade-off between classification and runtime performance, and show that up to 1 million classifications per second can be achieved for a single core. Considering that only the subset of flows reaching some minimum flow length will need to be classified, the results are promising with regards to deployment also in scenarios with very high flow arrival rates. HITS

A Comprehensive Analysis on Data Hazard for RISC32 5-Stage Pipeline Processor

Scipedia content — Thu, 28 Jan 2021 17:37:49 +0100

This paper describes the verification plan on data hazard detection and handling for a 32-bit MIPS ISA (Microprocessor without Interlocked Pipeline Stages Instruction Set Architecture) compatible 5-stage pipeline processor, RISC32. Our work can be used as a reference for RISC32 processor developers to identify and resolve every possible data hazard that might arise during execution phase within the range of the basic MIPS core instruction set. The techniques used to resolve data hazard in this paper are data forwarding and pipeline stages stalling. When data hazard arises, it is first resolve by using data forwarding. If the problem persists, we use pipeline stages stalling then only follow by another data forwarding to resolve the data hazard. This combination will reduce the impact of data hazard on the processor throughput, instead of only using the pipeline stages stalling. This paper delivers a comprehensive analysis and the development of the data hazard resolving blocks that are able to resolve data hazard arises.

I-TSA Traffic Safety Assessment in a Simulator Experiment with Integrated Information and Assistance Systems

Scipedia content — Thu, 28 Jan 2021 17:32:53 +0100

The increasing number and complexity of in-vehicle information systems (IVIS) and advanced driver assistance systems (ADAS) require an accurate and timely assessment of their impact on traffic safety even during the development process. The I-TSA evaluation tool, developed within the German research consortium INVENT, offers a standardized procedure for the assessment of traffic safety based on the driving error occurrence in up to 10 categories of parameters (e.g., the category “longitudinal control” includes the errors in speed, time headway and time to collision). The objective of the experiment presented here was to determine the validity and sensitivity of the I-TSA tool for this evaluation process. A homogeneous cohort of 41 young, healthy males (25 to 40 years old) drove for approximately 1 hour in a static simulator environment. The scenario on a two-lane motorway consisted of 4 counterbalanced drives with easy and difficult road shapes and traffic conditions. The trial included several interaction tasks with IVIS and ADAS differing in their stage of integration and adaptivity. The successful induction of high workload levels could be both detected by objective (such as speed compensation) and subjective measures (questionnaire). Highly significant differences in the safety levels were found between the easy and the difficult drives (demonstrating the suitability of the procedure) as well as between the sections with default and integrated behavior of the information systems (supporting its sensitivity). Preliminary results support the possibility of discriminating between visual and cognitive workload, as well as sensitivity to learning effects.

Application of electrostatic analogy method based on differential Ohm's law in NDT systems for monitoring internal defects in pipelines made of conductive materials in agriculture

Scipedia content — Thu, 28 Jan 2021 17:32:06 +0100

Automated Analysis of Remotely Sensed Images Using the Unicore Workflow Management System

Scipedia content — Thu, 28 Jan 2021 17:29:50 +0100

The progress of remote sensing technologies leads to increased supply of high-resolution image data. However, solutions for processing large volumes of data are lagging behind: desktop computers cannot cope anymore with the requirements of macro-scale remote sensing applications; therefore, parallel methods running in High-Performance Computing (HPC) environments are essential. Managing an HPC processing pipeline is non-trivial for a scientist, especially when the computing environment is heterogeneous and the set of tasks has complex dependencies. This paper proposes an end-to-end scientific workflow approach based on the UNICORE workflow management system for automating the full chain of Support Vector Machine (SVM)-based classification of remotely sensed images. The high-level nature of UNICORE workflows allows to deal with heterogeneity of HPC computing environments and offers powerful workflow operations such as needed for parameter sweeps. As a result, the remote sensing workflow of SVM-based classification becomes re-usable across different computing environments, thus increasing usability and reducing efforts for a scientist.

UNICARagil - Disruptive Modular Architectures for Agile, Automated Vehicle Concepts

Scipedia content — Thu, 28 Jan 2021 17:21:09 +0100

PUBLIC PERCEPTIONS OF URBAN SUSTAINABLE CHALLENGES IN DEVELOPING COUNTRIES

Scipedia content — Thu, 28 Jan 2021 17:19:54 +0100

Sustainable urban development is facing major challenges in developing countries, due to rapid urbanisation, lack of environmental strategies, energy consumption, transport congestion, and insufficient infrastructure. The degradation of public services and utilities has also been significant, particularly in politically unstable countries such as Iraq, whose cities have suffered from destruction, leading to severe damage to infrastructure and causing economic deterioration. In many of these countries, rebuilding projects are currently in progress and being planned, but the public are not being involved in the decision-making process. This study investigates public perceptions of sustainable urban challenges and their priorities for the Iraqi capital city of Baghdad; it also investigates social awareness of urban sustainability within the local Iraqi context. A national questionnaire (n=750) was conducted and participants’ views were gathered on a 5-point Likert-type scale. The findings revealed that 81% of the participants considered ‘providing green areas and parks’ as the most important goal in urban development. This was followed by ‘waste recycling and separation’ (74%) and ‘mitigation of traffic congestion’ (70.5%). The ‘minimisation of energy consumption’ was poorly rated, as only 37.7% of the respondents voted this as the least important item. The results reflect the key important factors related to the services and utilities, coinciding with an actual need to raise the public services, in order to provide the required indicators with a level of importance focuses on the local context. Therefore, these urban challenge indicators can play a vital role to provide effective public’s indicators for decision-makers, in order to improve the existing applications and the future urban projects to achieve quality of life.

The analysis of interdependence between corrosion, physical depreciation and market value in the evaluation process of special construction assets – pipeline transportation systems

Scipedia content — Thu, 28 Jan 2021 17:18:04 +0100

In the assessment of pipeline transportation systems is very important for the assessor to analyze how market value is influenced by the size of corrosion. It is also interesting to analyse the interdependence of corrosion, physical depreciation and market value. Evaluation of special construction assets like pipelines is a complicated process that does not use traditional approaches to evaluation, but rather a mixture of evaluation methods because each pipeline is unique in its own way, but also because its value is influenced by many factors.This paper present how varies size of corrosion, physical depreciation and market value and the corrosion is influenced by several factors. The corrosion process is a complex mechanism that occurs during operation of all equipment and technological equipment in the refineries or pipelines systems or found in petrochemical installations and is done at oscillating temperature and pressure (high/low), in the presence of some work environments (type: crude oil, compressed gases, petroleum and petrochemical products, etc.). Corrosion is defined as the destruction, in a certain span of time, of metals and metal alloys as a result of chemical and/or electrochemical actions of the technological environments and surrounding or due to physical dissolutions. From the point of view of the assessor-engineer whose aim is to determine the assessment of pipeline transportation for petroleum products one is able to highlight the influence of corrosion within its depreciation.The quantitative implementation of corrosion for the estimation of market value of technological pipelines is an ongoing concern of evaluators as engineers have been determining the existence of corrosion for a long time now, yet this could not be found in a mathematical relation that was to show the interdependence between corrosion, depreciation and the market value. The relation between depreciation and corrosion by means of this factor is very useful for assessors in predicting depreciation. The emphasizing of corrosion within the estimation of market value through the influence of the factor of depreciation due to corrosion is a first step in a broader process of research which is meant to mathematically highlight the dependence of impairment due to corrosion on the characteristics of the material which the pipe is made of.

Quantification and compensation of systematic errors in pressure measurements applied to oil pipelines

Scipedia content — Thu, 28 Jan 2021 17:17:08 +0100

The monitoring of pipeline operation is an important research topic, especially for the detection and localization of leaks as well as for an efficient control. For these purposes, physical quantities in pipelines are calculated from measurement data on the basis of a mathematical model. In contrast to static models, adaptive models vary their parameters or even their structure to reach the most probable solution. But in most cases, even the best fit will hold residuals caused by discrepancies between the real system and its model. These residuals allow an estimation of travel-time delays of pressure waves and offsets in pressure values. The basic idea of our approach is to interpret these systematic, time-invariant errors of pressure measurements in pipelines either as sensor displacements or as technical defects. The proposed procedure leads to a hypothesis for a model update, regarding the sensor positions. This displacement compensation as well as a variance analysis was successfully applied to real data from a crude oil pipeline in Europe. A cross validation proves the general capability of the developed method to reduce the uncertainties.

Soft-NMS — Improving Object Detection with One Line of Code

Scipedia content — Thu, 28 Jan 2021 17:16:05 +0100

Non-maximum suppression is an integral part of the object detection pipeline. First, it sorts all detection boxes on the basis of their scores. The detection box M with the maximum score is selected and all other detection boxes with a significant overlap (using a pre-defined threshold) with M are suppressed. This process is recursively applied on the remaining boxes. As per the design of the algorithm, if an object lies within the predefined overlap threshold, it leads to a miss. To this end, we propose Soft-NMS, an algorithm which decays the detection scores of all other objects as a continuous function of their overlap with M. Hence, no object is eliminated in this process. Soft-NMS obtains consistent improvements for the coco-style mAP metric on standard datasets like PASCAL VOC 2007 (1.7% for both R-FCN and Faster-RCNN) and MS-COCO (1.3% for R-FCN and 1.1% for Faster-RCNN) by just changing the NMS algorithm without any additional hyper-parameters. Using Deformable-RFCN, Soft-NMS improves state-of-the-art in object detection from 39.8% to 40.9% with a single model. Further, the computational complexity of Soft-NMS is the same as traditional NMS and hence it can be efficiently implemented. Since Soft-NMS does not require any extra training and is simple to implement, it can be easily integrated into any object detection pipeline. Code for Soft-NMS is publicly available on GitHub (http://bit.ly/2nJLNMu).

Comment: ICCV 2017 camera ready version