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Yan, Li. "On the traffic flow control system." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39431174.
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Yan, Li, and 顏理. "On the traffic flow control system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39431174.
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Almejalli, Khaled A., Keshav P. Dahal, and M. Alamgir Hossain. "Intelligent traffic control decision support system." Springer-Verlag, 2007. http://hdl.handle.net/10454/2554.
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When non-recurrent road traffic congestion happens, the operator of the traffic control centre has to select the most appropriate traffic control measure or combination of measures in a short time to manage the traffic network. This is a complex task, which requires expert knowledge, much experience and fast reaction. There are a large number of factors related to a traffic state as well as a large number of possible control measures that need to be considered during the decision making process. The identification of suitable control measures for a given non-recurrent traffic congestion can be tough even for experienced operators. Therefore, simulation models are used in many cases. However, simulating different traffic scenarios for a number of control measures in a complicated situation is very time-consuming. In this paper we propose an intelligent traffic control decision support system (ITC-DSS) to assist the human operator of the traffic control centre to manage online the current traffic state. The proposed system combines three soft-computing approaches, namely fuzzy logic, neural network, and genetic algorithm. These approaches form a fuzzy-neural network tool with self-organization algorithm for initializing the membership functions, a GA algorithm for identifying fuzzy rules, and the back-propagation neural network algorithm for fine tuning the system parameters. The proposed system has been tested for a case-study of a small section of the ring-road around Riyadh city. The results obtained for the case study are promising and show that the proposed approach can provide an effective support for online traffic control.
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Negi, Pallav. "Artificial Immune System based urban traffic control." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5764.
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Borrowing ideas from natural immunity, Artificial Immune Systems (AIS) offer a novel
approach to solving many diagnosis, optimization and control problems. In the course of
this research this paradigm was applied to the problem of optimizing urban traffic. The
traffic was micro-simulated with each car on a two junction road system modeled
individually. The cars themselves were programmed with 'personalities' to better
simulate real traffic. A novel AIS was developed to detect, predict, and control
anomalous traffic conditions. It was also used to optimize the flow of traffic through the
road network. Benchmarking was performed against the well accepted TRANSYT
traffic control system. Though the TRANSYT system performed better initially, the AIS
control showed marked improvement over time as it adapted better to changing traffic
conditions. This change was expected as TRANSYT is optimized for specific initial
conditions unlike the AIS system which adapts to changes.
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Lin, Joyce C. (Joyce Chaisin) 1979. "VisualFlight : the air traffic control data analysis system." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87266.
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Jaworski, P. "Cloud computing based adaptive traffic control and management." Thesis, Coventry University, 2013. http://curve.coventry.ac.uk/open/items/d63ba84e-bd0c-4e00-8242-310dbbaa3b92/1.
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Recent years have shown a growing concern over increasing traffic volume worldwide. The insufficient road capacity and the resulting congestions have become major problems in many urban areas. Congestions negatively impact the economy, the environment and the health of the population as well as the drivers satisfaction. Current solutions to this topical and timely problem rely on the exploitation of Intelligent Transportation Systems (ITS) technologies. ITS urban traffic management involves the collection and processing of a large amount of geographically distributed information to control distributed infrastructure and individual vehicles. The distributed nature of the problem prompted the development of a novel, scalable ITS-Cloud platform. The ITS-Cloud organises the processing and manages distributed data sources to provide traffic management methods with more accurate information about the state of the traffic. A new approach to service allocation, derived from the existing cloud and grid computing approaches, was created to address the unique needs of ITS traffic management. The ITS-Cloud hosts the collection of software services that form the Cloud based Traffic Management System (CTMS). CTMS combines intersection control algorithms with intersection approach advices to the vehicles and dynamic routing. The CTMS contains a novel Two-Step traffic management method that relies on the ITS-Cloud to deliver a detailed traffic simulation image and integrates an adaptive intersection control algorithm with a microscopic prediction mechanism. It is the first method able to perform simultaneous adaptive intersection control and intersection approach optimization. The Two-Step method builds on a novel pressure based adaptive intersection control algorithm as well as two new traffic prediction schemes. The developed traffic management system was evaluated using a new microscopic traffic simulation tool tightly integrated with the ITS-Cloud. The novel traffic management approaches were shown to outperform benchmark methods for a realistic range of traffic conditions and road network configurations. Unique to the work was the investigation of interactions between ITS components.
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Chow, Andy Ho Fai. "Adaptive traffic control system : a study of strategies, computational speed and effect of prediction error /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202002%20CHOW.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.Includes bibliographical references (leaves 126-129). Also available in electronic version. Access restricted to campus users.
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Grau, Mariani Rafael. "A demand-responsive traffic control system for urban areas." Doctoral thesis, Universitat Politècnica de Catalunya, 1995. http://hdl.handle.net/10803/399670.
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The goal of this Ph.D. Thesis is the design, development and testing of a 'well-engineered system' aimed at the demand-responsive traffic control of urban areas. Because of the author's background -software engineering-, a 'well-engineered system' means a system that is both efficient at performing its task in a wide range of conditions and also that has been built from the robust design's and ease-of-use's points of view. The work has proceed in four steps and, accordingly, this document has been divided in four parts that are briefly desc1ibed here.
PART I is, mainly, an introduction to the subject. It introduces the concept of demand responsiveness in traffic control, providing a historical perspective from traditional fixed control systems to current modern demand-responsive systems. The part concludes with a study of areas where research and improvement is needed. All of these areas are considered in the following parts, where some solutions are proposed.
PAR T II presents the design, development and preliminary tests of a demand responsive traffic control system, CARS V l, intended to operate in signalized urban areas: networks, arte1ials, and isolated intersections. A graphical user interface, X-Windows and DecWindows compliant, allows the user to specify network characteristics in a friendly and intuitive manner, without the need to be acquainted with the actual modeling. The system features an underlying simulation system and a prediction model based on real-time measured conditions, implements a centralized approach based on small variations, and has flexible detector positioning-and-number requirements.
PART III presents the design of a simulation environment, named GETRAM, that solves the difficulties in testing CARS that were discussed at the end of the previous part. We have seen that these difficulties are inherent in the traffic engineer having to use diverse models in order to analyze a traffic network, and that there is the need for a system to salve it. GETRAM provides a unified framework integrating various types of traffic models and tools for traffic analysis, sharing a DataBase, a graphical editor and a mod le for results presentation. The traffic network can be partitioned into views, hierarchically organized polygons in the real world, so that, for example, a simulation model applies only to one of these restricted areas. Network statcs produced by one model can be used as a starting point by another modcl. I n order to ease the task of integrating a new model or analysis tool, a library of object-based high-level functions provide a view-aware access to the DataBase, maintaining consistency. Included in this Ph.D. thesis are the design of the whole environment -DataBase, G ETR AM API, and graphical editor - and the development of the DataBase and GETRAM API.
PART IV starts from the demand-responsive traffic control system developed in PART II, CARS V l , and improves it in various respects. First, in order to ease the task of testing the system, it is integrated into the traffic modeling and analysis environment described in PART III. Second, certain parts that directly influence to the effectiveness of the system, such as control timing, adaptive control logics and communication with the controllers, are revised or totally redone. A suite of tests has been applied to the resulting system, CARS V2, in the four scenarios desc1ibed in PART 11. Finally, to further testing the system and taking advantage of the fact of having real-world data available, it is compared against a vehicle-actuated control at an isolated junction.El objetivo de esta tesis es el diseño, desarrollo y test por simulación microscópica de un sistema autoadaptativo apto para cruces aislados, arterias y redes urbanas complejas. El sistema produce planes de control acíclicos y presenta unos requerimientos de tiempo real muy flexibles debidos a utilizar una nueva secuencia cíclica de tareas en la que se predice el estado del sistema a corto término antes de probar planes de control alternativos. Estas pruebas se realizan mediante un modelo interno de simulación que sigue un enfoque mesoscópico a base de paquetes de vehículos de velocidad variable, con el que se consigue modelizar la dinámica de colas de vehículos de forma más exacta que con los sistemas actualmente existentes. Esto da una ventaja, corroborada en los test, en condiciones de flujo altas, con lo que el sistema de controles es capaz de mantener una buena efectividad en un amplio rango de condiciones de tráfico. El sistema viene acompañado de un entorno de simulación y test que aporta un alto grado de integración y de facilidad de uso, a lo largo de todo el proceso de especificación de geometría, parámetros y ejecución de simulación se mantiene una vista de la red de tráfico altamente realista.
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Abdelfatah, Akmal Saad. "Time-dependent signal control and system optimal traffic assignment in congested vehicular traffic networks /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Yu, Tungsheng. "On-line Traffic Signalization using Robust Feedback Control." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/26334.
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The traffic signal affects the life of virtually everyone every day. The effectiveness of signal systems can reduce the incidence of delays, stops, fuel consumption, emission of pollutants, and accidents. The problems related to rapid growth in traffic
congestion call for more effective traffic signalization using robust feedback control methodology.
Online traffic-responsive signalization is based on real-time traffic conditions and selects cycle, split, phase, and offset for the intersection according to detector data. A robust traffic feedback control begins with assembling traffic demands, traffic facility supply, and feedback
control law for the existing traffic operating environment. This information serves the input to the traffic control process
which in turn provides an output in terms of the desired performance under varying conditions.
Traffic signalization belongs to a class of hybrid systems since the differential equations model the continuous behavior of the traffic flow dynamics and finite-state machines model the discrete state changes of the controller. A complicating aspect, due to the state-space
constraint that queue lengths are necessarily nonnegative, is that the continuous-time system dynamics is actually the
projection of a smooth system of ordinary differential equations. This also leads to discontinuities in the boundary dynamics
of a sort common in queueing problems.
The project is concerned with the design of a feedback controller to minimize accumulated queue lengths in the presence of unknown inflow disturbances at an isolated intersection and a traffic network with some signalized intersections. A dynamical system has finite L2-gain if it is dissipative in some sense. Therefore, the Hinfinity-control problem turns to designing a controller such that the resulting closed loop system is dissipative, and correspondingly there exists a storage function.
The major contributions of this thesis include 1) to propose state space models for both isolated multi-phase intersections and a class of queueing networks; 2) to formulate Hinfinity problems for the control systems with persistent disturbances; 3) to present the projection dynamics aspects of the problem to account for the constraints on the state variables; 4) formally to study this problem as a hybrid system; 5) to derive traffic-actuated feedback control laws for the multi-phase intersections. Though we have mathematically presented a robust feedback solution for the traffic signalization, there still remains some distance before the physical implementation. A robust adaptive control is an interesting research area for the future traffic signalization.
Ph. D.
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Cuneo, David J. (David Joseph) 1972. "A system-wide evaluation of a traffic control system using microscopic simulation." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/10104.
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Sheng, Li. "THE INTERACTIVE HARDWARE-IN-LOOP SIMULATION SYSTEM FOR TRAFFIC CONTROL SYSTEM DEVELOPMENT." University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1132429944.
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Sheu, Hsin-Teng. "A coordinated decentralized flow and routing control algorithm for an automated highway system /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu148758564557836.
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Maslekar, Nitin. "Adaptive Traffic Signal Control System Based on Inter-Vehicular Communication." Rouen, 2011. http://www.theses.fr/2011ROUES046.
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Traffic signal control, which is an integral part of Intelligent Transportation System (ITS), plays an important role in regulating vehicular flow at road intersections. With the increase of vehicular traffic, there has been a significant degradation in the functional efficiency of signal systems. Traditional systems are not capable of adjusting the timing pattern in accordance with vehicular demand. This results in excessive delays for road users. Hence it is necessary to develop dynamic systems that can adjust the timing patterns according to traffic demand. Of the various available techniques, Vehicular Adhoc Networks (VANETs) are attracting considerable attention from the research community and the automotive industry to implement dynamic systems. In this context, exchanging data among vehicles is one of the key technological enablers through which the density of vehicles approaching the intersection can be predicted. This requires extensive collaboration between vehicles. Inherent properties and limitations of VANETs, distributing information among the vehicles is a very challenging task. In this thesis, an adaptive traffic signal control system based on car-to-car communication (VANETs) is proposed. To achieve this, a data dissemination technique titled, Clustering in DiRectIon in Vehicular Environment (C-DRIVE) is implemented. In C-DRIVE, the formation of clusters is based on the direction metric. Precisely this metric defines the direction a vehicle will travel after crossing the intersection. To attain stability within the clusters and to have accurate estimation of the density of vehicles, two policies are adapted. In the first policy, a clusterhead switching mechanism is defined. In the second method, termed as Modified C-DRIVE (MC-DRIVE), the clusterhead election policy is modified. In this modification the election policy is based on the stable cluster length. Once the clusters are formed, the elected cluster head will compute the density in its clusters and transmits the information to the traffic signal controller (TSC). With the density information of different lanes approaching the intersection, at the TSC an optimal cycle length is computed using the modified Webster’s model and based on the demand, required green splits are allotted to the various phase. The efficiency of this method is advocated through simulation results which show that the waiting time for vehicles and queue length at intersections are considerably reduced. It is also shown that the proposed solution is collision free at intersections. The proposed system is compared with a classic pre-timed system and an adaptive fuzzy logic system. The simulations also show that the data convergence time and the communication delay between vehicles and traffic signals do not compromise the efficiency of the system.
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Lu, Chao. "A self-learning motorway traffic control system for ramp metering." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7895/.
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Self-learning systems have attracted increasing attention in the ramp metering domain in recent years. These systems are based on reinforcement learning (RL) and can learn to control motorway traffic adaptively. However, RL-based ramp metering systems are still in their early stages and have shown limitations regarding their design and evaluation. This research aims to develop a new RL-based system (known as RAS) for ramp metering to overcome these limitations. A general framework for designing a RL-based system is proposed in this research. It contains the definition of three RL elements in a ramp metering scenario and a system structure which brings together all modules to accomplish the reinforcement learning process. Under this framework, two control algorithms for both single- and multi-objective problems are developed. In addition, to evaluate the proposed system, a software platform combining the new system and a traffic flow model is developed in the research. Based on the platform developed, a systematic evaluation is carried out through a series of simulation-based experiments. By comparing with a widely used control strategy, ALINEA, the proposed system, RAS, has shown its effectiveness in learning the optimal control actions for different control objectives in both hypothetical and real motorway networks. It is found that RAS outperforms ALINEA on improving traffic efficiency in the situation with severe congestion and on maintaining user equity when multiple on-ramps are included in the motorway network. Moreover, this research has been extended to use indirect learning technology to deal with incident-induced congestion. Tests for this extension to the work are carried out based on the platform developed and a commercial software package, AIMSUN, which have shown the potential of the extended system in tackling incident-induced congestion.
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Le, Tru Huy. "Performance and availability analysis of Oceanic Air Traffic Control System (OATCS)." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-01242009-063216/.
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OKUMA, Shigeru, Tatsuya SUZUKI, YoungWoo KIM, and Tatsuya KATO. "Model Predictive Control of Traffic Flow Based on Hybrid System Modeling." Institute of Electronics, Information and Communication Engineers, 2005. http://hdl.handle.net/2237/14988.
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Shelby, Steven Gebhart. "Design and evaluation of real-time adaptive traffic signal control algorithms." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279933.
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This dissertation investigates methods of real-time adaptive traffic signal control in the context of single isolated intersection and coordinated urban network applications. A primary goal in this dissertation is to identify and address scenarios where real-time optimized controllers do not maintain competitive performance with off-line calibrated, vehicle-actuated control techniques. An extensive literature review is supplemented by subsequent simulation experiments. Several strategies were implemented and evaluated, including OPAC, PRODYN, COP, ALLONS-D, Webster's optimized fixed-time control, and vehicle-actuated control. In particular, evaluation is based on simulation of a single, isolated intersection, where all algorithms are required to adopt the exact, deterministic traffic model used by the simulation. This approach eliminates confounding factors in comparison of algorithms, such as detector placement and disparate traffic models, focusing evaluation on the efficiency of the algorithms and their ultimate performance in terms of vehicle delay. A new algorithm is developed, employing neuro-dynamic programming techniques, also known as reinforcement learning techniques. Several very effective pruning strategies are also constructed. The final product is a very efficient algorithm capable of solving problems up to 2000 times faster than the most efficient previously published algorithm tested, with an 8% decrease in delay. This algorithm is then extended to a generalized, multi-ring control formulation. Simulation results with a standard dual-ring, eight-phase controller demonstrate that efficient, real-time solutions are achieved with a corresponding 12--22% reduction in delay relative to dual-ring, vehicle-actuated control. The real-time optimized, multi-ring controller is finally extended for urban network applications, expanding the objective function to consider downstream performance measures, and adopt standard, vehicle-actuated type coordination constraints. Control on an 8-intersection arterial is evaluated using a CORSIM simulation over a range of traffic conditions. Results are compared with TRANSYT optimized fixed-time control, coordinated vehicle-actuated control, and RHODES. Two regimes of control are revealed, where cyclic coordination constraints provide a significant benefit, and where they prevent more effective control. An adaptive coordination layer is prescribed as a unifying architecture with the potential of obtaining effective control under both regimes. The adaptive control layer specification is explicitly distinguished from existing algorithms, such as SCOOT, SCATS, and VFC-OPAC.
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Urban, Brian L. "Propagation analysis of a 900 MHz spread spectrum centralized traffic signal control system." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5242/.
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The objective of this research is to investigate different propagation models to determine if specified models accurately predict received signal levels for short path 900 MHz spread spectrum radio systems. The City of Denton, Texas provided data and physical facilities used in the course of this study. The literature review indicates that propagation models have not been studied specifically for short path spread spectrum radio systems. This work should provide guidelines and be a useful example for planning and implementing such radio systems. The propagation model involves the following considerations: analysis of intervening terrain, path length, and fixed system gains and losses.
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Jörneskog, Gustav, and Josef Kandelan. "Using Deep Reinforcement Learning For Adaptive Traffic Control in Four-Way Intersections." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-158204.
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The consequences of traffic congestion include increased travel time, fuel consumption, and the number of crashes. Studies suggest that most traffic delays are due to nonrecurring traffic congestion. Adaptive traffic control using real-time data is effective in dealing with nonrecurring traffic congestion. Many adaptive traffic control algorithms used today are deterministic and prone to human error and limitation. Reinforcement learning allows the development of an optimal traffic control policy in an unsupervised manner. We have implemented a reinforcement learning algorithm that only requires information about the number of vehicles and the mean speed of each incoming road to streamline traffic in a four-way intersection. The reinforcement learning algorithm is evaluated against a deterministic algorithm and a fixed-time control schedule. Furthermore, it was tested whether reinforcement learning can be trained to prioritize emergency vehicles while maintaining good traffic flow. The reinforcement learning algorithm obtains a lower average time in the system than the deterministic algorithm in eight out of nine experiments. Moreover, the reinforcement learning algorithm achieves a lower average time in the system than the fixed-time schedule in all experiments. At best, the reinforcement learning algorithm performs 13% better than the deterministic algorithm and 39% better than the fixed-time schedule. Moreover, the reinforcement learning algorithm could prioritize emergency vehicles while maintaining good traffic flow.
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Björck, Erik, and Fredrik Omstedt. "A comparison of algorithms used in traffic control systems." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229709.
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A challenge in today's society is to handle a large amount of vehicles traversing an intersection. Traffic lights are often used to control the traffic flow in these intersections. However, there are inefficiencies since the algorithms used to control the traffic lights do not perfectly adapt to the traffic situation. The purpose of this paper is to compare three different types of algorithms used in traffic control systems to find out how to minimize vehicle waiting times. A pretimed, a deterministic and a reinforcement learning algorithm were compared with each other. Test were conducted on a four-way intersection with various traffic demands using the program Simulation of Urban MObility (SUMO). The results showed that the deterministic algorithm performed best for all demands tested. The reinforcement learning algorithm performed better than the pretimed for low demands, but worse for varied and higher demands. The reasons behind these results are the deterministic algorithm's knowledge about vehicular movement and the negative effects the curse of dimensionality has on the training of the reinforcement learning algorithm. However, more research must be conducted to ensure that the results obtained are trustworthy in similar and different traffic situations.En utmaning i dagens samhälle är att hantera en stor mängd fordon som kör igenom en korsning. Trafikljus används ofta för att kontrollera trafikflödena genom dessa korsningar. Det finns däremot ineffektiviteter eftersom algoritmerna som används för att kontrollera trafikljusen inte är perfekt anpassade till trafiksituationen. Syftet med denna rapport är att jämföra tre typer av algoritmer som används i trafiksystem för att undersöka hur väntetid för fordon kan minimeras. En tidsbaserad, en deterministisk och en förstärkande inlärning-algoritm jämfördes med varandra. Testerna utfördes på en fyrvägskorsning med olika trafikintensiteter med hjälp av programmet Simulation of Urban MObility (SUMO). Resultaten visade att den deterministiska algoritmen presterade bäst för alla olika trafikintensiteter. Inlärningsalgoritmen presterade bättre än den tidsbaserade på låga intensiteter, men sämre på varierande och högre intensiteter. Anledningarna bakom resultaten är att den deterministiska algoritmen har kunskap om hur fordon rör sig samt att dimensionalitetsproblem påverkar träningen av inlärningsalgoritmen negativt. Det krävs däremot mer forskning för att säkerställa att resultaten är pålitliga i liknande och annorlunda trafiksituationer.
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Karlsson, Joakim. "The integration of automatic speech recognition into the air traffic control system." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/42184.
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Galvin, James J. "Air Traffic Control Resource Management Strategies and the Small Aircraft Transportation System: A System Dynamics Perspective." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/29988.
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The National Aeronautics and Space Administration (NASA) is leading a research effort to develop a Small Aircraft Transportation System (SATS) that will expand air transportation capabilities to hundreds of underutilized airports in the United States. Most of the research effort addresses the technological development of the small aircraft as well as the systems to manage airspace usage and surface activities at airports. The Federal Aviation Administration (FAA) will also play a major role in the successful implementation of SATS, however, the administration is reluctant to embrace the unproven concept.
The purpose of the research presented in this dissertation is to determine if the FAA can pursue a resource management strategy that will support the current radar-based Air Traffic Control (ATC) system as well as a Global Positioning Satellite (GPS)-based ATC system required by the SATS. The research centered around the use of the System Dynamics modeling methodology to determine the future behavior of the principle components of the ATC system over time.
The research included a model of the ATC system consisting of people, facilities, equipment, airports, aircraft, the FAA budget, and the Airport and Airways Trust Fund. The model generated system performance behavior used to evaluate three scenarios. The first scenario depicted the base case behavior of the system if the FAA continued its current resource management practices. The second scenario depicted the behavior of the system if the FAA emphasized development of GPS-based ATC systems. The third scenario depicted a combined resource management strategy that supplemented radar systems with GPS systems.
The findings of the research were that the FAA must pursue a resource management strategy that primarily funds a radar-based ATC system and directs lesser funding toward a GPS-based supplemental ATC system. The most significant contribution of this research was the insight and understanding gained of how several resource management strategies and the presence of SATS aircraft may impact the future US Air Traffic Control system.Ph. D.
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Sarasua, Wayne Alexander. "SIG-GIS : a GIS based traffic signal coordination and information management system." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/19085.
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NUNES, LUCIANA SILVEIRA NETTO. "DECISION SUPPORT SYSTEM FOR THE OPERATIONAL CONTROL CENTER IN THE RAILROAD TRAFFIC MANAGEMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4923@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOEsta pesquisa tem por objetivo conceber um sistema de apoio à decisão ao centro de controle operacional no gerenciamento do tráfego ferroviário. O sistema consiste na resolução de conflitos entre trens. Esta pesquisa justifica- se devido à deficiência encontrada pelos controladores de tráfego na tomada de decisões. Atualmente, as prioridades dos trens são pré-estabelecidas e, a partir da análise de um gráfico feito à medida que os eventos ocorrem, o planejamento do despacho de trens é realizado. As prioridades podem ser modificadas ao longo do dia, a partir de alguma ordem superior. Assim, existe a necessidade do desenvolvimento de um novo sistema que auxilie os controladores de tráfego na determinação da melhor solução para os conflitos entre trens. Inicialmente, foram realizados os levantamentos bibliográficos e de dados. Na revisão bibliográfica, foram analisados o sequenciamento de trens, condições de ultrapassagem e de cruzamentos e modelos de programação de trens. Em seguida, foi aplicada uma heurística proposta por Leal (2003) desenvolvida a partir da formulação de Szpigel (1972) e implementada em um programa de computador, na linguagem delphi. Esta heurística apresenta uma solução para os conflitos entre trens. A aplicação foi baseada nos dados fornecidos pela empresa MRS logística, situada em Juiz de Fora (MG). A partir da solução gerada por Leal (2003), foi desenvolvido um gráfico no Excel, utilizando a linguagem visual basic, onde são analisadas as programações dos trens com a solução dos conflitos. O objetivo final desta pesquisa é sugerir uma ferramenta de auxílio para o gerenciamento do tráfego ferroviário, contribuindo para a evolução e eficiência das ferrovias no Brasil.
The objective of this research is to conceive a decision support system for the operational control center in the railroad traffic management. The system consists of the resolution of conflict between trains. The justification of this research is due to the deficiency founded by controllers of traffic in the decisions making. Currently, the trains priorities are previously established and, through the analysis of a done graph to the measure that the events go happening, these priorities can be modified. Thus, there is the necessity of the development of a new system which helps the controllers in the determination of the best alternative. Initially, the bibliographical surveys and the data-collectings had been made. In the bibliographic revision, the sequenciament of trains, ultraticket and crossing conditions, and trains programming models had been analyzed. The next step was the application of an heuristic developed by Leal (2003), based in the formularization of Szpigel (1972), and implemented in a computer program, in the Delphi language, showing the solution of conflicts between trains. The application was based in the data of MRS logistic company, situated in Juiz De Fora (MG). From the solution generated for Leal (2003), a graph in the excel was developed, using visual basic language, and shows the programmings of the trains with conflits solution. The final objective is to suggest a tool for helping the railroad traffic management, contributing for the evolution and efficiency of the railroads in Brazil.
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Reynolds, Hayley J. Davison (Hayley Jaye Davison). "Identification of communication and coordination issues in the U.S. air traffic control system." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/81565.
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De, Freitas Martinez Andres, and Nurdin Mohamed. "Managing Validation in a Safety Critical System Regarding Automation of Air Traffic Control." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246073.
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The aviation industry is under increasing pressure to reduce cost and manage the increased number of passengers. One area under pressure is the Air Traffic Control. The Air Traffic Control will in a foreseeable future manage the introduction of drones also known as Unmanned Aerial Vehicles by integrating them into civil airspace with manned aircraft. Drones are lacking consensus from authorities with regards to standards due to their rapid expansion. Given their size, shape and speed, they can also pose threats to manned aircrafts and there is a need to address them in an Air Traffic Management system interoperating with manned aircrafts. The purpose in this study is to identify what considerations to make when automating complex system elements with respect to safety. Safety involves all the different stakeholders in the air transportation system, which is a Safety critical System. Furthermore, the aim is also to identify areas in which European Operational Concept Validation Methodology (E-OCVM) can be complemented with. Standard E-OCVM is missing specific assessment criteria with regards to safety and how it can interact with other standards. The approach is thereby to use various standards with focus on Systems Engineering to complement E-OCVM since it is lacking with regards to how it is used to validate Air Traffic Control systems. To capture the complexity of automating elements of an industry involving many stakeholders, a qualitative analysis was conducted in this project, using a System Engineering approach with four standards A-SLP, A-RLP, A-DAS and A-SAS. A-SLP and A-RLP are two general standards while A-DAS and A-SAS are focusing on the contexts of aircrafts and software development. Empirical data was gathered by semi-structured interviews of seven experts within the relevant areas in the field. From the review of the four standards, it was found that they can for instance complement E-OCVM in how software errors can lead to a failure condition among other ways. The main identified considerations faced with an integration of drones into civil airspace, is to manage the human interaction with the introduced Air Traffic Management systems. More specifically, the human element must be involved from the training phase in the development of systems in a Safety Critical System to minimize risk. Furthermore, redundancies that are built into the system has to, not only be able to put the system into a safe state, but also be carefully analyzed in how they interact with other systems to avoid misjudgement for the Air Traffic Controllers. Lastly, to obtain specific details on how interoperability could occur using standards, the standards used in this study refer to usage of other documents and standards. Standards specifically tailored for the operational context of drones would facilitate further testing and implementation of their integration into civil airspace. Given that different standards were used to complement the EOCVM standard, a set of unified standards are required that are proportional with the type of drones, the type of operations and in the environment that they are operating in. This will be needed to fulfill the European vision of safe integration of drones and needs thereby to be carried out in a global manner, thus also share experience with other actors to advance the new technology adaptation.
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Barbosa, Wagner. "The design of an integrated production and inventory control system for a traffic sign shop." Ohio : Ohio University, 1990. http://www.ohiolink.edu/etd/view.cgi?ohiou1183477955.
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Thall, Anders. "Trafikstyrning med variabel trafikutrustning : en behovsanalys för Vägverket Region Stockholm." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2814.
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When traffic in large cities increases, it becomes more vulnerable to disturbances such as accidents, stalled vehicles or construction; therefore, traffic jams are more likely to occur. For better control of the traffic at a disturbance the Swedish National Road Administration (SNRA) has traffic equipment which can be controlled from a command centre. This traffic equipment consists of gates and signs with variable messages. This report will discuss the system used for traffic control in Stockholm. It will present proposals designed to improve it.
These proposals were prepared based on interviews with people from SNRA and their contractors as well as on comparisons with existing systems.
The focus of this report is the handling of system alarms and graphical user interface. By implementing the proposals in this report, the following will be achieved:
· More efficient alarmcontrol - the errors are discovered immediately or soon after they occur
· Clearer information regarding alarms - the traffic operator receives better information about the error
· Better control of the traffic equipment - the control will be easier and more flexible.
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Nassir, Neema. "Optimal Integrated Dynamic Traffic Assignment and Signal Control for Evacuation of Large Traffic Networks with Varying Threat Levels." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/297042.
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This research contributes to the state of the art and state of the practice in solving a very important and computationally challenging problem in the areas of urban transportation systems, operations research, disaster management, and public policy. Being a very active topic of research during the past few decades, the problem of developing an efficient and practical strategy for evacuation of real-sized urban traffic networks in case of disasters from different causes, quickly enough to be employed in immediate disaster management scenarios, has been identified as one of the most challenging and yet vital problems by many researchers. More specifically, this research develops fast methods to find the optimal integrated strategy for traffic routing and traffic signal control to evacuate real-sized urban networks in the most efficient manner. In this research a solution framework is proposed, developed and tested which is capable of solving these problems in very short computational time. An efficient relaxation-based decomposition method is proposed, implemented for two evacuation integrated routing and signal control model formulations, proven to be optimal for both formulations, and verified to reduce the computational complexity of the optimal integrated routing and signal control problem. The efficiency of the proposed decomposition method is gained by reducing the integrated optimal routing and signal control problem into a relaxed optimal routing problem. This has been achieved through an insight into intersection flows in the optimal routing solution: in at least one of the optimal solutions of the routing problem, each street during each time interval only carries vehicles in at most one direction. This property, being essential to the proposed decomposition method, is called "unidirectionality" in this dissertation. The conditions under which this property exists in the optimal evacuation routing solution are identified, and the existence of unidirectionality is proven for: (1) the common Single-Destination System-Optimal Dynamic Traffic Assignment (SD-SODTA) problem, with the objective to minimize the total time spent in the threat area; and, (2) for the single-destination evacuation problem with varying threat levels, with traffic models that have no spatial queue propagation. The proposed decomposition method has been implemented in compliance with two widely-accepted traffic flow models, the Cell Transmission Model (CTM) and the Point Queue (PQ) model. In each case, the decomposition method finds the optimal solution for the integrated routing and signal control problem. Both traffic models have been coded and applied to a realistic real-size evacuation scenario with promising results. One important feature that is explored is the incorporation of evacuation safety aspects in the optimization model. An index of the threat level is associated with each link that reflects the adverse effects of traveling in a given threat zone on the safety and health of evacuees during the process of evacuation. The optimization problem is then formulated to minimize the total exposure of evacuees to the threat. A hypothetical large-scale chlorine gas spill in a high populated urban area (downtown Tucson, Arizona) has been modeled for testing the evacuation models where the network has varying threat levels. In addition to the proposed decomposition method, an efficient network-flow solution algorithm is also proposed to find the optimal routing of traffic in networks with several threat zones, where the threat levels may be non-uniform across different zones. The proposed method can be categorized in the class of "negative cycle canceling" algorithms for solving minimum cost flow problems. The unique feature in the proposed algorithm is introducing a multi-source shortest path calculation which enables the efficient detection and cancellation of negative cycles. The proposed method is proven to find the optimal solution, and it is also applied to and verified for a mid-size test network scenario.
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Xie, Yuanchang. "Development and evaluation of an arterial adaptive traffic signal control system using reinforcement learning." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2480.
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Weigang, Li. "Knowledge-based system for air traffic flow management : timetable rescheduling and centralized flow control." Instituto Tecnológico de Aeronáutica, 1994. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1711.
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Future air traffic management (ATM) systems have been identified as a matter of great significance for the evolution of future air navigation systems (FANS). As one function of ATM, Air Traffic Flow Management (ATFM) provides a service complementary to Air Traffic Control (ATC). In this research, a Knowledge-Based System (KBS) has been designed to try to solve the ATFM problem. For timetable rescheduling, the system attempts to modify airlines tiemtable to smooth traffic peaks at airports during rush-hours. For centralized flow control, the system works on-line to forecast the place, time and magnitude of the congestion and to take some actions to prevent this congestion. As an Artificial Intelligence language, Prolog was chosen for developing the prototype of the Knowledge-Based ATFM System. The research gives a conceptual description of the application of KBS (specially in Prolog) in the ATFM domain. Using this system, a study of the Brazilian ATFM systemincluding the main airports of the country has been done.
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Al-Ghamdi, Ali Saeed. "The development of expert system for actuated control of traffic (EXACT) at isolated intersections /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487759436328344.
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Jefferson, Robin Linton. "A two-way data-communications system for traffic control applications utilising a passive microwave transponder." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293588.
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Scott, Jenifer M. B. "The application of artificial neural networks to the control of a road traffic monitoring system." Thesis, University of Aberdeen, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248623.
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This thesis describes the development of a new Road Traffic Monitoring (RTM) system designed by a team at the University of Aberdeen, to provide low cost traffic monitoring that maintains the privacy of the driver and provides high quality traffic data for the authorities. The RTM system communicates with vehicles equipped with satellite transceivers attached to Global Positioning System (GPS) units which provide data about position and velocity, enabling a picture to be built up of traffic flow conditions. The author developed an innovative system to maintain the anonymity of the driver in order for the system to be attractive to both authorities and drivers. The thesis focuses on the author's contribution to the project - the design of the major protocols, including polling and 'system wide' strategies, an in-depth study of the statistics of the capacity of the RTM system and the development of a protocol to limit the number of responses from vehicles to a manageable level. The RTM system was implemented as a simulation and all designed protocols and parameters thoroughly tested. It is currently being used by the European Space Agency in a pilot study as the first phase of implementation. The author then envisaged an intelligent control system that would monitor and control the RTM system in real time, optimising parameters dynamically in order for the system to run efficiently and accurately. A hybrid 'Artificial Intelligence' (AI) system composed of a rule based system and a number of Artificial Neural Networks (ANNs) is proposed. A new rule extraction system developed by the author to counter the 'black box' effect of ANNs is then presented, making use of a hierarchical system of Self Organising Maps (SOMs). Following this, an extension to the system is described, using the Quantisation Error (QE) to enable the real time detection of 'unusual' data, or data from outwith the current operating environment, enabling retraining or the return to a previous control situation, to take place. Such a system of ANNs is ideal for use in both monitoring and control of a dynamic real time system such as RTM.
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Timotijevic, Tijana. "System level performance of ATM transmission over a DS-CDMA satellite link." Thesis, Queen Mary, University of London, 1999. http://qmro.qmul.ac.uk/xmlui/handle/123456789/3821.
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Zamanipour, Mehdi, and Mehdi Zamanipour. "A Unified Decision Framework for Multi-Modal Traffic Signal Control Optimization in a Connected Vehicle Environment." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/620993.
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Motivated by recent advances in vehicle positioning and vehicle-to-infrastructure (V2I) communication, traffic signal controllers are able to make smarter decisions. Most of the current state-of-the-practice signal priority control systems aim to provide priority for only one mode or based on first-come-first-served logic. Consideration of priority control in a more general framework allows for several different modes of travelers to request priority at any time from any approach and for other traffic control operating principles, such as coordination, to be considered within an integrated signal timing framework. This leads to provision of priority to connected priority eligible vehicles with minimum negative impact on regular vehicles. This dissertation focuses on providing a real-time decision making framework for multi modal traffic signal control that considers several transportation modes in a unified framework using Connected Vehicle (CV) technologies. The unified framework is based on a systems architecture for CVs that is applicable in both simulated and real world (field) testing conditions. The system architecture is used to design both hardware-in-the-loop and software-in-the-loop CV simulation environment. A real-time priority control optimization model and an implementation algorithm are developed using priority eligible vehicles data. The optimization model is extended to include signal coordination concepts. As the penetration rate of the CVs increases, the ability to predict the queue more accurately increases. It is shown that accurate queue prediction improves the performance of the optimization model in reducing priority eligible vehicles delay. The model is generalized to consider regular CVs as well as priority vehicles and coordination priority requests in a unified mathematical model. It is shown than the model can react properly to the decision makers' modal preferences.
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Switzer, Earl, Michael Whelan, and Farncisco Lagunas. "AIR TRAFFIC CONTROL COMMUNICATIONS TEST FACILITY AND AVIONICS SYSTEM TEST (ACTFAST): GEARING UP FOR NEXT GENERATION AVIONICS SYSTEMS TESTING." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/608285.
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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, CaliforniaGrowth in civil aviation is overwhelming worldwide airspace and air traffic services. The International Civil Aviation Organization (ICAO), Federal Aviation Administration (FAA) and Department of Defense (DoD) are proposing or implementing numerous changes to address this growth. The changes are broadly contained in what the civil aviation community calls Communication, Navigation, and Surveillance/Air Traffic Management (CNS/ATM) and the DoD calls Global Air Traffic Management (GATM). A major component of both civil and DoD proposed changes are data link systems digitally transmitting information between aircraft, air traffic control centers, and aircraft operations centers. The real-time interactive nature of these data-link systems and the integration of the aircraft avionics into a worldwide network are forcing aircraft test agencies to acquire access to this capability. Aircraft flighttesting must address both the specific aircraft avionics test requirements and the system-of-systems aspects of data-link applications. This paper describes the factors driving changes in the worldwide CNS/ATM system and identifies specific proposed or implemented changes. Various flight-test requirements, both civil and military, of the proposed changes are enumerated. Particular attention is paid to the DoDs GATM certification requirements. Finally, we present the Air Traffic Control Communications Test Facility and Avionics System Test (ACTFAST) program and explain its capabilities. Rationale for ACTFAST component parts is included along with a brief outline of how the capabilities represented by each component part are used during flight test to acquire the necessary information to meet civil and DoD aircraft certification requirements.
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Beak, Byungho, and Byungho Beak. "Systematic Analysis and Integrated Optimization of Traffic Signal Control Systems in a Connected Vehicle Environment." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626304.
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Traffic signal control systems have been tremendously improved since the first colored traffic signal light was installed in London in December 1868. There are many different types of traffic signal control systems that can be categorized into three major control types: fixed-time, actuated, and adaptive. Choosing a proper traffic signal system is very important since there exists no perfect signal control strategy that fits every traffic network. One example is traffic signal coordination, which is the most widely used traffic signal control system. It is believed that performance measures, such as travel times, vehicle delay, and number of stops, can be enhanced by synchronizing traffic signals over a corridor. However, it is not always true that the coordination will have the same benefits for all the traffic in the network. Most of the research on coordination has focused only on strengthening the major movement along the coordinated routes without considering system-wide impacts on other traffic.
Therefore, before implementing a signal control system to a specific traffic network, a thorough investigation should be conducted to see how the control strategy may impact the entire network in terms of the objectives of each type of traffic control system. This dissertation first considers two different kinds of systematic performance analyses for traffic signal control systems. Then, it presents two types of signal control strategies that account for current issues in coordination and priority control systems, respectively.
First, quantitative analysis of smooth progression for traffic flow is investigated using connected vehicle technology. Many studies have been conducted to measure the quality of progression, but none has directly considered smooth progression as the significant factor of coordination, despite the fact that the definition of coordination states that the goal is to have smooth traffic flow. None of the existing studies concentrated on measuring a continuous smooth driving pattern for each vehicle in terms of speed. In order to quantify the smoothness, this dissertation conducts an analysis of the speed variation of vehicles traveling along a corridor. A new measure is introduced and evaluated for different kinds of traffic control systems. The measure can be used to evaluate how smoothly vehicles flow along a corridor based on the frequency content of vehicle speed. To better understand the impact of vehicle mode, a multi-modal analysis is conducted using the new measure.
Second, a multi-modal system-wide evaluation of traffic signal systems is conducted. This analysis is performed for traffic signal coordination, which is compared with fully actuated control in terms of a systematic assessment. Many optimization models for coordination focus mainly on the objective of the coordinated route and do not account for the impacts on side street movements or other system-wide impacts. In addition, multi-modality is not considered in most optimized coordination plans. Thus, a systematic investigation of traffic signal coordination is conducted to analyze the benefits and impacts on the entire system. The vehicle time spent in the system is measured as the basis of the analysis. The first analysis evaluates the effect of coordination on each route based on a single vehicle mode (regular passenger vehicles). The second analysis reveals that how multi-modality affects the performance of the entire system.
Third, in order to address traffic demand fluctuation and traffic pattern changes during coordination periods, this dissertation presents an adaptive optimization algorithm that integrates coordination with adaptive signal control using data from connected vehicles. Through the algorithm, the coordination plan can be updated to accommodate the traffic demand variation and remain optimal over the coordination period. The optimization framework consists of two levels: intersection and corridor. The intersection level handles phase allocation in real time based on connected vehicle trajectory data, while the corridor level deals with the offsets optimization. The corridor level optimization focuses on the performance of the vehicle movement along the coordinated phase, while at the intersection level, all movements are considered to create the optimal signal plan. The two levels of optimizations apply different objective functions and modeling methodologies. The objective function at the intersection level is to minimize individual vehicle delay for both coordinated and non-coordinated phases using dynamic programming (DP). At the corridor level, a mixed integer linear programming (MILP) is formulated to minimize platoon delay for the coordinated phase.
Lastly, a peer priority control strategy, which is a methodology that enhances the multi modal intelligent traffic signal system (MMITSS) priority control model, is presented based on peer-to-peer (P2P) and dedicated short range communication (DSRC) in a connected vehicle environment. The peer priority control strategy makes it possible for a signal controller to have a flexible long-term plan for prioritized vehicles. They can benefit from the long-term plan within a secured flexible region and it can prevent the near-term priority actions from having a negative impact on other traffic by providing more flexibility for phase actuation. The strategy can be applied to all different modes of vehicles such as transit, freight, and emergency vehicles. Consideration for far side bus stops is included for transit vehicles.
The research that is presented in this dissertation is constructed based on Standard DSRC messages from connected vehicles such as Basic Safety Messages (BSMs), Signal Phasing and Timing Messages (SPaTs), Signal Request Messages (SRMs), and MAP Messages, defined by Society of Automotive Engineers (SAE) (SAE International 2016).
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Tana, Kebron Temedo. "Interoperability Study of the European and Chinese Railway Signalling Systems : Case study in Ethiopia." Thesis, KTH, Transportplanering, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-301302.
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The railway industry in Ethiopia has been an important way of communication and transportation for a long time. It is a developing sector with many national plans for future investments. However, the current major corridors of Ethio-Djibouti and Awash-Weldiya have interoperability issues due to two different signalling systems being used. Thus, this study was undertaken with the objectives of assessing technical interoperability of the Chinese signalling system (CTCS) and the European signalling system (ETCS), identifying a possible technical solution regarding the interoperability issues, and assessing the economic benefits of a harmonized system. Compatibility of the two signalling systems was analyzed particularly with respect tothe technical configurations by thoroughly investigating each system’s features and making interviews and having discussions with professionals who worked with the two systems. In addition, a life cycle cost analysis of the EthioDjibouti signalling system was done with data obtained from Ethiopian Railway Corporation and compared with average life cycle costs of ETCS level 1. After analyzing each system, two possible technical solutions were found to achieve interoperability between the two systems used in Ethiopia currently. The first technical solution is upgrading EthioDjiboutirailway line from the current CTCS level 0 to CTCS level 2 to be compatible with the new AwashWeldiya line which will use ETCS level 1. The second technical solution to make the two systems interoperable is to install ERTMS as an overlay on the existing CTCS level 0 as ERTMS is designed as an overlay system that could be installed on top of an existing national infrastructure and vehicles. However, these technical solutions have to be tested in laboratory and onsite with respect to their practical and economical feasibility.Järnvägsindustrin i Etiopien har länge varit viktig för kommunikation och transport. Det är en sektor under utveckling med många nationella planer för framtida investeringar. De nuvarande korridorerna i EthioDjibouti och AwashWeldiya har emellertid interoperabilitetsproblem på grund av två olika signalsystem. Detta examensarbete har analyserat kompatibiliteten för de två signalsystemen särskilt med avseende på de tekniska konfigurationerna genom att noggrant undersöka varje systems funktioner och genom intervjuer och diskussioner med yrkesverksamma somhar arbetat med de två systemen. Dessutom genomfördes en livscykelkostnadsanalys av EthioDjibouti signalssystemet med den data som erhölls från Ethiopian Railway Corporation. Efter analys av varje system hittades två möjliga tekniska lösningar för att uppnå interoperabilitet mellan de två systemen som används i Etiopien för närvarande. Den första tekniska lösningen är att uppgradera EthioDjiboutis järnvägslinje från nuvarande CTCS nivå 0 till CTCS nivå 2 för att vara kompatibel med den nya AwashWeldiyalinjen som kommer att använda ETCS nivå 1. Den andra tekniska lösningen för att göra de två systemen interoperabla är att installera ERTMS som ett överlägg på det befintliga CTCS0 signalsystemet, eftersom ERTMS är utformat som ett överläggssystem som kan installeras ovanpå en befintlig nationell infrastruktur. Dessa tekniska lösningar måste dock testas i laboratorium och i fält med avseende på deras praktiska och ekonomiska genomförbarhet.
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Kesting, Arne. "Microscopic Modeling of Human and Automated Driving: Towards Traffic-Adaptive Cruise Control." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1204804167720-57734.
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The thesis is composed of two main parts. The first part deals with a microscopic traffic flow theory. Models describing the individual acceleration, deceleration and lane-changing behavior are formulated and the emerging collective traffic dynamics are investigated by means of numerical simulations. The models and simulation tools presented provide the methodical prerequisites for the second part of the thesis in which a novel concept of a traffic-adaptive control strategy for ACC systems is presented. The impact of such systems on the traffic dynamics can solely be investigated and assessed by traffic simulations. The focus is on future adaptive cruise control (ACC) systems and their potential applications in the context of vehicle-based intelligent transportation systems. In order to ensure that ACC systems are implemented in ways that improve rather than degrade traffic conditions, the thesis proposes an extension of ACC systems towards traffic-adaptive cruise control by means of implementing an actively jam-avoiding driving strategy. The newly developed traffic assistance system introduces a driving strategy layer which modifies the driver's individual settings of the ACC driving parameters depending on the local traffic situation. Whilst the conventional operational control layer of an ACC system calculates the response to the input sensor data in terms of accelerations and decelerations on a short time scale, the automated adaptation of the ACC driving parameters happens on a somewhat longer time scale of, typically, minutes. By changing only temporarily the comfortable parameter settings of the ACC system in specific traffic situations, the driving strategy is capable of improving the traffic flow efficiency whilst retaining the comfort for the driver. The traffic-adaptive modifications are specified relative to the driver settings in order to maintain the individual preferences. The proposed system requires an autonomous real-time detection of the five traffic states by each ACC-equipped vehicle. The formulated algorithm is based on the evaluation of the locally available data such as the vehicle's velocity time series and its geo-referenced position (GPS) in conjunction with a digital map. It is assumed that the digital map is complemented by information about stationary bottlenecks as most of the observed traffic flow breakdowns occur at these fixed locations. By means of a heuristic, the algorithm determines which of the five traffic states mentioned above applies best to the actual traffic situation. Optionally, inter-vehicle and infrastructure-to-car communication technologies can be used to further improve the accuracy of determining the respective traffic state by providing non-local information. By means of simulation, we found that the automatic traffic-adaptive driving strategy improves traffic stability and increases the effective road capacity. Depending on the fraction of ACC vehicles, the driving strategy "passing a bottleneck" effects a reduction of the bottleneck strength and therefore delays (or even prevents) the breakdown of traffic flow. Changing to the driving mode "leaving the traffic jam" increases the outflow from congestion resulting in reduced queue lengths in congested traffic and, consequently, a faster recovery to free flow conditions. The current travel time (as most important criterion for road users) and the cumulated travel time (as an indicator of the system performance) are used to evaluate the impact on the quality of service. While traffic congestion in the reference scenario was completely eliminated when simulating a proportion of 25% ACC vehicles, travel times were significantly reduced even with much lower penetration rates. Moreover, the cumulated travel times decreased consistently with the increase in the proportion of ACC vehiclesIn der Arbeit wird ein neues verkehrstelematisches Konzept für ein verkehrseffizientes Fahrverhalten entwickelt und als dezentrale Strategie zur Vermeidung und Auflösung von Verkehrsstaus auf Richtungsfahrbahnen vorgestellt. Die operative Umsetzung erfolgt durch ein ACC-System, das um eine, auf Informationen über die lokale Verkehrssituation basierende, automatisierte Fahrstrategie erweitert wird. Die Herausforderung bei einem Eingriff in das individuelle Fahrverhalten besteht - unter Berücksichtigung von Sicherheits-, Akzeptanz- und rechtlichen Aspekten - im Ausgleich der Gegensätze Fahrkomfort und Verkehrseffizienz. Während sich ein komfortables Fahren durch große Abstände bei geringen Fahrzeugbeschleunigungen auszeichnet, erfordert ein verkehrsoptimierendes Verhalten kleinere Abstände und eine schnellere Anpassung an Geschwindigkeitsänderungen der umgebenden Fahrzeuge. Als allgemeiner Lösungsansatz wird eine verkehrsadaptive Fahrstrategie vorgeschlagen, die ein ACC-System mittels Anpassung der das Fahrverhalten charakterisierenden Parameter umsetzt. Die Wahl der Parameter erfolgt in Abhängigkeit von der lokalen Verkehrssituation, die auf der Basis der im Fahrzeug zur Verfügung stehenden Informationen automatisch detektiert wird. Durch die Unterscheidung verschiedener Verkehrssituationen wird ein temporärer Wechsel in ein verkehrseffizientes Fahrregime (zum Beispiel beim Herausfahren aus einem Stau) ermöglicht. Machbarkeit und Wirkungspotenzial der verkehrsadaptiven Fahrstrategie werden im Rahmen eines mikroskopischen Modellierungsansatzes simuliert und hinsichtlich der kollektiven Verkehrsdynamik, insbesondere der Stauentstehung und Stauauflösung, auf mehrspurigen Richtungsfahrbahnen bewertet. Die durchgeführte Modellbildung, insbesondere die Formulierung eines komplexen Modells des menschlichen Fahrverhaltens, ermöglicht eine detaillierte Analyse der im Verkehr relevanten kollektiven Stabilität und einer von der Stabilität abhängigen stochastischen Streckenkapazität. Ein tieferes Verständnis der Stauentstehung und -ausbildung wird durch das allgemeine Konzept der Engstelle erreicht. Dieses findet auch bei der Entwicklung der Strategie für ein stauvermeidendes Fahrverhalten Anwendung. In der Arbeit wird die stauvermeidende und stauauflösende Wirkung eines individuellen, verkehrsadaptiven Fahrverhaltens bereits für geringe Ausstattungsgrade nachgewiesen. Vor dem Hintergrund einer zu erwartenden Verbreitung von ACC-Systemen ergibt sich damit eine vielversprechende Option für die Steigerung der Verkehrsleistung durch ein teilautomatisiertes Fahren. Der entwickelte Ansatz einer verkehrsadaptiven Fahrstrategie ist unabhängig vom ACC-System. Er erweitert dessen Funktionalität im Hinblick auf zukünftige, informationsbasierte Fahrerassistenzsysteme um eine neue fahrstrategische Dimension. Die lokale Interpretation der Verkehrssituation kann neben einer verkehrsadaptiven ACC-Regelung auch der Entwicklung zukünftiger Fahrerinformationssysteme dienen
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Gettman, Douglas Mark 1971. "A multi-objective integrated large-scale optimized ramp metering control system for freeway/surface-street traffic management." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282797.
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This research, denoted MILOS (Multi-objective Integrated Large-scale Optimized ramp metering System) is a hierarchical structure for solution of the large-scale freeway management problem to address the key features of this problem (dynamic state changes, stochasticity, multi-dimensionality, unpredictability, partial-observability, and existence of multiple objectives). MILOS decomposes the freeway control problem into subproblems along temporal/spatial boundaries and is composed of three primary components: SPC-based anomaly detection and optimization scheduling, area-wide coordination layer, and predictive-cooperative real-time (PC-RT) optimization layer. The area-wide coordination component of the hierarchical control system considers the impact of queue growth on the adjacent interchanges in a quadratic programming optimization model with a multi-criterion objective function. The formulation of the area-wide optimization problem is augmented with overflow variables to guarantee a feasible solution. The nominal solution of the areawide coordination problem is then modified in real-time by the locally traffic-reactive, PC-RT algorithm based on a linear-program using a linearized dynamic difference equation implementation of the macroscopic FREFLO model. The PC-RT formulation pro-actively plans to utilize opportunities to disperse queues or hold back additional vehicles when freeway and ramp demand conditions are appropriate. The cost coefficients of this optimization problem is linked to the solution of the area-wide coordination problem by using information on the dual of the solution to the area-wide coordination problem. The optimization runs of the area-wide coordination problem and the PC-RT optimization problems at each ramp are scheduled by a demand/flow monitoring system based on statistical process control. A simulation experiment is executed to evaluate the MILOS hierarchical system against "no control", ADOT's current ramp metering policy, and an area-wide LP optimization problem resolved in 5-minute intervals on a small freeway network in the metropolitan Phoenix, AZ area. Three test cases are presented for a short "burst" of heavy-volume flows to all ramps, a 3-hour commuting peak, and a 3-hour commuting peak with a 30-minute incident occurring in the middle of the network. The performance results indicate that MILOS is able to reduce freeway travel time, increase freeway average speed, and improve recovery performance of the system when flow conditions become congested.
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Wigetman, Robert. "Vers la conception du système Sieel : un tuteur intelligent pour le contrôle aérien." Toulouse 3, 1994. http://www.theses.fr/1994TOU30258.
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Nous decrivons dans cette these les travaux de conception et de developpement d'un tuteur intelligent pour le controle aerien. Celui-ci comprend trois modules: un simulateur de trafic aerien et son interface homme machine, un systeme expert de controle aerien, et un systeme expert pedagogue. Nos travaux sont centres sur ce dernier module qui a ete concu de facon a etre aussi independant que possible du domaine du controle aerien, et ainsi de pouvoir s'appliquer a d'autres domaines du meme type. Pour ce faire, nous avons caracterise le travail du controleur par des strategies de planification d'actions qu'il doit mettre en uvre pour resoudre des problemes a la fois complexes et dynamiques auxquels il est confronte. A partir de cette caracterisation, nous avons concu une structure, en forme de graphe, pour rendre explicite les relations entre les connaissances utilisees. Ce graphe de connaissances est la fondation sur laquelle est bati notre systeme. Apres une introduction au domaine du controle aerien, nous presentons des generalites sur les tuteurs intelligents et decrivons quelques uns de ces systemes. Puis, nous presentons l'ensemble du systeme sieel de l'ecole nationale de l'aviation civile. Vient par la suite la description de nos travaux dans le detail: tout d'abord, l'analyse de la semantique des communications entre l'eleve et les agents simules a eu pour resultat l'implantation d'une grammaire de cas. Ensuite, la structuration des connaissances enseignees a permis l'elaboration d'un modele d'eleve a couverture partielle. Enfin, notre tuteur utilise ces elements pour comparer les actions de l'eleve avec les plans hypothetiques produits par un systeme expert du domaine afin d'evaluer son niveau d'expertise et de pouvoir determiner des interventions de guidage a mettre en uvre
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Beamon, Courtney A. "Design framework for the graphical user interface of a terminal area air traffic advisory system." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-11182008-063554/.
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Kesting, Arne. "Microscopic Modeling of Human and Automated Driving: Towards Traffic-Adaptive Cruise Control." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A24070.
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The thesis is composed of two main parts. The first part deals with a microscopic traffic flow theory. Models describing the individual acceleration, deceleration and lane-changing behavior are formulated and the emerging collective traffic dynamics are investigated by means of numerical simulations. The models and simulation tools presented provide the methodical prerequisites for the second part of the thesis in which a novel concept of a traffic-adaptive control strategy for ACC systems is presented. The impact of such systems on the traffic dynamics can solely be investigated and assessed by traffic simulations. The focus is on future adaptive cruise control (ACC) systems and their potential applications in the context of vehicle-based intelligent transportation systems. In order to ensure that ACC systems are implemented in ways that improve rather than degrade traffic conditions, the thesis proposes an extension of ACC systems towards traffic-adaptive cruise control by means of implementing an actively jam-avoiding driving strategy. The newly developed traffic assistance system introduces a driving strategy layer which modifies the driver's individual settings of the ACC driving parameters depending on the local traffic situation. Whilst the conventional operational control layer of an ACC system calculates the response to the input sensor data in terms of accelerations and decelerations on a short time scale, the automated adaptation of the ACC driving parameters happens on a somewhat longer time scale of, typically, minutes. By changing only temporarily the comfortable parameter settings of the ACC system in specific traffic situations, the driving strategy is capable of improving the traffic flow efficiency whilst retaining the comfort for the driver. The traffic-adaptive modifications are specified relative to the driver settings in order to maintain the individual preferences. The proposed system requires an autonomous real-time detection of the five traffic states by each ACC-equipped vehicle. The formulated algorithm is based on the evaluation of the locally available data such as the vehicle's velocity time series and its geo-referenced position (GPS) in conjunction with a digital map. It is assumed that the digital map is complemented by information about stationary bottlenecks as most of the observed traffic flow breakdowns occur at these fixed locations. By means of a heuristic, the algorithm determines which of the five traffic states mentioned above applies best to the actual traffic situation. Optionally, inter-vehicle and infrastructure-to-car communication technologies can be used to further improve the accuracy of determining the respective traffic state by providing non-local information. By means of simulation, we found that the automatic traffic-adaptive driving strategy improves traffic stability and increases the effective road capacity. Depending on the fraction of ACC vehicles, the driving strategy "passing a bottleneck" effects a reduction of the bottleneck strength and therefore delays (or even prevents) the breakdown of traffic flow. Changing to the driving mode "leaving the traffic jam" increases the outflow from congestion resulting in reduced queue lengths in congested traffic and, consequently, a faster recovery to free flow conditions. The current travel time (as most important criterion for road users) and the cumulated travel time (as an indicator of the system performance) are used to evaluate the impact on the quality of service. While traffic congestion in the reference scenario was completely eliminated when simulating a proportion of 25% ACC vehicles, travel times were significantly reduced even with much lower penetration rates. Moreover, the cumulated travel times decreased consistently with the increase in the proportion of ACC vehicles.In der Arbeit wird ein neues verkehrstelematisches Konzept für ein verkehrseffizientes Fahrverhalten entwickelt und als dezentrale Strategie zur Vermeidung und Auflösung von Verkehrsstaus auf Richtungsfahrbahnen vorgestellt. Die operative Umsetzung erfolgt durch ein ACC-System, das um eine, auf Informationen über die lokale Verkehrssituation basierende, automatisierte Fahrstrategie erweitert wird. Die Herausforderung bei einem Eingriff in das individuelle Fahrverhalten besteht - unter Berücksichtigung von Sicherheits-, Akzeptanz- und rechtlichen Aspekten - im Ausgleich der Gegensätze Fahrkomfort und Verkehrseffizienz. Während sich ein komfortables Fahren durch große Abstände bei geringen Fahrzeugbeschleunigungen auszeichnet, erfordert ein verkehrsoptimierendes Verhalten kleinere Abstände und eine schnellere Anpassung an Geschwindigkeitsänderungen der umgebenden Fahrzeuge. Als allgemeiner Lösungsansatz wird eine verkehrsadaptive Fahrstrategie vorgeschlagen, die ein ACC-System mittels Anpassung der das Fahrverhalten charakterisierenden Parameter umsetzt. Die Wahl der Parameter erfolgt in Abhängigkeit von der lokalen Verkehrssituation, die auf der Basis der im Fahrzeug zur Verfügung stehenden Informationen automatisch detektiert wird. Durch die Unterscheidung verschiedener Verkehrssituationen wird ein temporärer Wechsel in ein verkehrseffizientes Fahrregime (zum Beispiel beim Herausfahren aus einem Stau) ermöglicht. Machbarkeit und Wirkungspotenzial der verkehrsadaptiven Fahrstrategie werden im Rahmen eines mikroskopischen Modellierungsansatzes simuliert und hinsichtlich der kollektiven Verkehrsdynamik, insbesondere der Stauentstehung und Stauauflösung, auf mehrspurigen Richtungsfahrbahnen bewertet. Die durchgeführte Modellbildung, insbesondere die Formulierung eines komplexen Modells des menschlichen Fahrverhaltens, ermöglicht eine detaillierte Analyse der im Verkehr relevanten kollektiven Stabilität und einer von der Stabilität abhängigen stochastischen Streckenkapazität. Ein tieferes Verständnis der Stauentstehung und -ausbildung wird durch das allgemeine Konzept der Engstelle erreicht. Dieses findet auch bei der Entwicklung der Strategie für ein stauvermeidendes Fahrverhalten Anwendung. In der Arbeit wird die stauvermeidende und stauauflösende Wirkung eines individuellen, verkehrsadaptiven Fahrverhaltens bereits für geringe Ausstattungsgrade nachgewiesen. Vor dem Hintergrund einer zu erwartenden Verbreitung von ACC-Systemen ergibt sich damit eine vielversprechende Option für die Steigerung der Verkehrsleistung durch ein teilautomatisiertes Fahren. Der entwickelte Ansatz einer verkehrsadaptiven Fahrstrategie ist unabhängig vom ACC-System. Er erweitert dessen Funktionalität im Hinblick auf zukünftige, informationsbasierte Fahrerassistenzsysteme um eine neue fahrstrategische Dimension. Die lokale Interpretation der Verkehrssituation kann neben einer verkehrsadaptiven ACC-Regelung auch der Entwicklung zukünftiger Fahrerinformationssysteme dienen.
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Almejalli, Khaled A. "Intelligent Real-Time Decision Support Systems for Road Traffic Management. Multi-agent based Fuzzy Neural Networks with a GA learning approach in managing control actions of road traffic centres." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4264.
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The selection of the most appropriate traffic control actions to solve non-recurrent traffic congestion is a complex task which requires significant expert knowledge and experience. In this thesis we develop and investigate the application of an intelligent traffic control decision support system for road traffic management to assist the human operator to identify the most suitable control actions in order to deal with non-recurrent and non-predictable traffic congestion in a real-time situation. Our intelligent system employs a Fuzzy Neural Networks (FNN) Tool that combines the capabilities of fuzzy reasoning in measuring imprecise and dynamic factors and the capabilities of neural networks in terms of learning processes. In this work we present an effective learning approach with regard to the FNN-Tool, which consists of three stages: initializing the membership functions of both input and output variables by determining their centres and widths using self-organizing algorithms; employing an evolutionary Genetic Algorithm (GA) based learning method to identify the fuzzy rules; tune the derived structure and parameters using the back-propagation learning algorithm. We evaluate experimentally the performance and the prediction capability of this three-stage learning approach using well-known benchmark examples. Experimental results demonstrate the ability of the learning approach to identify all relevant fuzzy rules from the training data. A comparative analysis shows that the proposed learning approach has a higher degree of predictive capability than existing models. We also address the scalability issue of our intelligent traffic control decision support system by using a multi-agent based approach. The large network is divided into sub-networks, each of which has its own associated agent. Finally, our intelligent traffic control decision support system is applied to a number of road traffic case studies using the traffic network in Riyadh, in Saudi Arabia. The results obtained are promising and show that our intelligent traffic control decision support system can provide an effective support for real-time traffic control.
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Vallur, Rajendran Avinash. "A Methodology for Development of Look Ahead Based Energy Management System Using Traffic In Loop Simulation." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1514828055131881.
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CHANG, PEL-NUNG, and 張培農. "Intelligent Traffic Control System." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/26212080222420994356.
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碩士明志科技大學
機電工程研究所
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That’s too many vehicles in recent year, make the traffic more and more complicated in the city. The traditional traffic control system already has been unable to overcome and handle the vehicle movement in more and more crowed traffic density. Using the Petri net and Fuzzy control become the intelligent judgment rule to be the basis of this system, and cooperate with RFID (Radio frequency identification) to make out vehicles and find the information of traffic situation, the information included: traffic flow, speed, weather, time and traffic control rule to control traffic number, to achieve the goal of intelligent traffic control system in this paper. This system used the LabVIEW to realized the all the situation of traffic and traffic number in this paper, to improve the any trouble in traffic number, and it can raise the average vehicle speed in the city, moreover solve the traffic jam. Furthermore can contribute the image of the country and develop the industry of tour. Keywords: Petri Net, Fuzzy control, Radio frequency identification, Intelligent traffic control system.
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"Traffic Network System Control Based on Hybrid Dynamical System." Thesis, 2007. http://hdl.handle.net/2237/7525.
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Kato, Tatsuya, and 龍也 加藤. "Traffic Network System Control Based on Hybrid Dynamical System." Thesis, 2007. http://hdl.handle.net/2237/7525.
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