Dissertations / Theses: 'Road traffic simulation'

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Igbe, Damian. "Dynamic load balancing of parallel road traffic simulation." Thesis, University of Westminster, 2010. https://westminsterresearch.westminster.ac.uk/item/90644/dynamic-load-balancing-of-parallel-road-traffic-simulation.

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The objective of this research was to investigate, develop and evaluate dynamic load-balancing strategies for parallel execution of microscopic road traffic simulations. Urban road traffic simulation presents irregular, and dynamically varying distributed computational load for a parallel processor system. The dynamic nature of road traffic simulation systems lead to uneven load distribution during simulation, even for a system that starts off with even load distributions. Load balancing is a potential way of achieving improved performance by reallocating work from highly loaded processors to lightly loaded processors leading to a reduction in the overall computational time. In dynamic load balancing, workloads are adjusted continually or periodically throughout the computation. In this thesis load balancing strategies were evaluated and some load balancing policies developed. A load index and a profitability determination algorithms were developed. These were used to enhance two load balancing algorithms. One of the algorithms exhibits local communications and distributed load evaluation between the neighbour partitions (diffusion algorithm) and the other algorithm exhibits both local and global communications while the decision making is centralized (MaS algorithm). The enhanced algorithms were implemented and synthesized with a research parallel traffic simulation. The performance of the research parallel traffic simulator, optimized with the two modified dynamic load balancing strategies were studied.

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Wilson, Richard Edward. "Modelling, analysis and simulation of road traffic networks." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268101.

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Axelsson, Eva, and Therese Wilson. "Microscopic simulation as an evaluation tool for the road safety of vulnerable road users." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130010.

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Traffic safety has traditionally been measured by analyzing historical accident data, which is a reactive method where a certain number of accidents must occur in order to identify the safety problem. An alternative safety assessment method is to use proximal safety indicators that are defined as measures of accident proximity, which is considered a proactive method. With this method it is possible to detect the safety problem before the accidents have happened. To be able to detect problems in traffic situations in general, microscopic simulation is commonly used. In these models it may be possible to generate representative near-accidents, measured by proximal safety indicator techniques. A benefit of this would be the possibility to experiment with different road designs and evaluate the traffic safety level before reconstructions of the road infrastructure. Therefore has an investigation been performed to test the possibility to identify near-accidents (conflicts) in a microscopic simulation model mimicking the Traffic Conflict Technique developed by Hydén (1987). In order to perform the investigation a case study has been used where an intersection in the city center of Stockholm was studied. The intersection has been rebuilt, which made it possible to perform a before and after study. For the previous design there was a traffic safety assessment available which was carried out using the Traffic Conflict Technique. Microscopic simulation models representing the different designs of the intersection were built in PTV Vissim. In order to evaluate and measure the traffic safety in reality as well as in the microscopic simulation models, a traffic safety assessment was performed in each case. The traffic safety assessment in field for the present design was carried out as a part of this thesis. The main focus of this thesis was the road safety for vulnerable road users. The method to identify conflicts in the simulation model has been to extract raw data output from the simulation model and thereafter process this data in a Matlab program, aiming to mimic the Traffic Conflict Technique. The same program and procedure was used for both the previous and the present design of the intersection. The results from the traffic safety assessment in the simulation model have been compared to the results from the field study in order to evaluate how well microscopic simulation works as an evaluation tool for traffic safety in new designs. The comparison shows that the two methods of conflict identification cannot replace each other straight off. But with awareness of the differences between the methods, the simulation model could be used as an indication when evaluating the level of traffic safety in a road design.

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Zhao, Qiang. "Multi-model based simulation in the reconstruction of road traffic accident." Thesis, Loughborough University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500371.

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A Synthetic Traffic SIMluation (ST-SIM) framework is constructed in this project. The framework provides a computer-based platform for traffic research, consisting of three modules: Driver Behaviour, Vehicle Dynamics, and Road Network modelling. Based on these models, ST-SIM can construct and simulate a broad range of traffic scenarios, including accidents. The research in this project has concentrated on the contribution of driver behaviour to the formation of normal traffic and traffic failure, ST-SIM has been designed and implemented using Agent-based modelling techniques. The software has been validated using simulator based driver collision avoidance behaviour from TRL and applied to help the accident reconstruction work of On-The-Spot (OTS) team in the UK.

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Moukir, Sara. "High performance analysis for road traffic control." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASG039.

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La réduction des temps de trajet et de la consommation d'énergie dans les réseaux routiers urbains est cruciale pour le bien-être collectif et la durabilité environnementale. Depuis les années 1950, la modélisation du trafic a été un axe central de la recherche. Avec l'évolution des capacités informatiques, des simulations sophistiquées représentant fidèlement les complexités du trafic routier ont émergé, essentielles pour évaluer les technologies sans perturber le trafic réel.Les systèmes de transport deviennent plus complexes avec des informations en temps réel, nécessitant des modèles de simulation adaptés. Les simulations multi-agents, analysant les comportements individuels dans un environnement dynamique, sont particulièrement efficaces pour cette tâche, permettant de comprendre et de gérer le trafic urbain en représentant les interactions entre les voyageurs et leur environnement.Simuler de grandes populations de voyageurs dans les villes a longtemps été une tâche exigeante en termes de ressources informatiques. Les technologies avancées permettant la distribution des calculs sur plusieurs ordinateurs ont ouvert de nouvelles possibilités. Cependant, de nombreux simulateurs de mobilité urbaine n'exploitent pas pleinement ces architectures distribuées, limitant leur capacité à modéliser des scénarios complexes.L'objectif principal de cette recherche est d'améliorer la performance algorithmique et computationnelle des simulateurs de mobilité. Nous développons et validons des modèles de distribution génériques et reproductibles pouvant être adoptés par divers simulateurs de mobilité multi-agents, surmontant ainsi les barrières techniques pour analyser les systèmes de transport complexes dans des environnements urbains dynamiques.Nous utilisons le simulateur de trafic MATSim, reconnu pour la simulation de trafic multi-agents, pour tester nos méthodes génériques. Notre première contribution applique l'approche "Unite and Conquer" (UC) à MATSim. Cette méthode accélère les simulations en exploitant les architectures informatiques modernes. L'approche multiMATSim réplique plusieurs instances de MATSim sur plusieurs nœuds de calcul avec des communications périodiques, chaque instance fonctionnant sur un nœud séparé, utilisant les capacités de multithreading de MATSim pour améliorer le parallélisme. La synchronisation périodique assure la cohérence des données, tandis que les mécanismes de tolérance aux pannes permettent à la simulation de se poursuivre même en cas d'échec de certaines instances. Cette approche optimise l'utilisation des ressources informatiques selon les capacités spécifiques de chaque nœud.La deuxième contribution explore les techniques d'intelligence artificielle pour accélérer la simulation. Nous utilisons des réseaux de neurones profonds pour prédire les résultats des simulations MATSim. Initialement mise en œuvre sur un seul nœud, cette approche de preuve de concept utilise efficacement les ressources CPU disponibles. Les réseaux de neurones sont entraînés sur des données de simulations précédentes pour prédire des indicateurs tels que les temps de trajet et les niveaux de congestion. Les résultats sont comparés à ceux de MATSim pour évaluer leur précision. Cette approche est conçue pour évoluer avec des plans futurs pour une formation distribuée sur plusieurs nœuds.En résumé, nos contributions fournissent de nouvelles variantes algorithmiques et explorent l'intégration du calcul haute performance et de l'IA dans les simulateurs de trafic multi-agents. Nous démontrons l'impact de ces modèles et technologies sur la simulation de trafic, en abordant les défis et les limites de leur mise en œuvre. Notre travail met en évidence les avantages des architectures émergentes et des nouveaux concepts algorithmiques pour améliorer la robustesse et la performance des simulateurs de trafic, avec des résultats prometteurs
The need to reduce travel times and energy consumption in urban road networks is critical for improving collective well-being and environmental sustainability. Since the 1950s, traffic modeling has been a central research focus. With the rapid evolution of computing capabilities in the 21st century, sophisticated digital simulations have emerged, accurately depicting road traffic complexities. Mobility simulations are essential for assessing emerging technologies like cooperative systems and dynamic GPS navigation without disrupting real traffic.As transport systems become more complex with real-time information, simulation models must adapt. Multi-agent simulations, which analyze individual behaviors within a dynamic environment, are particularly suited for this task. These simulations help understand and manage urban traffic by representing interactions between travelers and their environment.Simulating large populations of travelers in cities, potentially millions of individuals, has historically been computationally demanding. Advanced computer technologies allowing distributed calculations across multiple computers have opened new possibilities. However, many urban mobility simulators do not fully exploit these distributed architectures, limiting their ability to model complex scenarios involving many travelers and extensive networks.The main objective of this research is to improve the algorithmic and computational performance of mobility simulators. We aim to develop and validate generic and reproducible distribution models that can be adopted by various multi-agent mobility simulators. This approach seeks to overcome technical barriers and provide a solid foundation for analyzing complex transport systems in dynamic urban environments.Our research leverages the MATSim traffic simulator due to its flexibility and open structure. MATSim is widely recognized in the literature for multi-agent traffic simulation, making it an ideal candidate to test our generic methods.Our first contribution applies the "Unite and Conquer" (UC) approach to MATSim. This method accelerates simulation speed by leveraging modern computing architectures. The multiMATSim approach involves replicating several MATSim instances across multiple computing nodes with periodic communications. Each instance runs on a separate node, utilizing MATSim's native multithreading capabilities to enhance parallelism. Periodic synchronization ensures data consistency, while fault tolerance mechanisms allow the simulation to continue smoothly even if some instances fail. This approach efficiently uses diverse computational resources based on each node's specific capabilities.The second contribution explores artificial intelligence techniques to expedite the simulation process. Specifically, we use deep neural networks to predict MATSim simulation outcomes. Initially implemented on a single node, this proof-of-concept approach efficiently uses available CPU resources. Neural networks are trained on data from previous simulations to predict key metrics like travel times and congestion levels. The outputs are compared to MATSim results to assess accuracy. This approach is designed to scale, with future plans for distributed neural network training across multiple nodes.In summary, our contributions provide new algorithmic variants and explore integrating high-performance computing and AI into multi-agent traffic simulators. We aim to demonstrate the impact of these models and technologies on traffic simulation, addressing the challenges and limitations of their implementation. Our work highlights the benefits of emerging architectures and new algorithmic concepts for enhancing the robustness and performance of traffic simulators, presenting promising results

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Mashaoo, D. "Improvement of expert analysis for road traffic accidents using computer simulation programs." Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/14622.

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Chatterjee, Indrajit Edara Praveen K. "Replication of freeway work zone capacity values in a microscopic simulation model." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/6287.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb. 12, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Praveen K. Edara. Includes bibliographical references.

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Tapani, Andreas. "A Traffic Simulation Modeling Framework for Rural Highways." Licentiate thesis, Linköping : Linköpings universitet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4803.

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Rahimi, Mostafa. "Modeling and simulation of vehicle emissions for the reduction of road traffic pollution." Doctoral thesis, Università degli studi di Trento, 2023. https://hdl.handle.net/11572/365449.

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The transportation sector is responsible for the majority of airborne particles and global energy consumption in urban areas. Its role in generating air pollution in urban areas is even more critical, as many visitors, commuters and citizens travel there daily for various reasons. Emissions released by transport fleets have an exhaust (tailpipe) and a non-exhaust (brake wears ) origin. Both exhaust and non-exhaust airborne particles can have destructive effects on the human cardiovascular and respiratory systems and even lead to premature deaths. This dissertation aims to estimate the amount of exhaust and brake emissions in a real case study by proposing an innovative methodology. For this purpose, different levels of study have been introduced, including the subsystem level, the system level, the environmental level and the suprasystem level. To address these levels, two approaches were proposed along with a data collection process. First, a comprehensive field survey was conducted in the area of Buonconsiglio Castle and data was collected on traffic and non-traffic during peak hours. Then, in the first approach, a state-of-the-art simulation-based method was presented to estimate the amount of exhaust emissions generated and the rate of fuel consumption in the case study using the VISSIM traffic microsimulation software and Enviver emission modeler at the suprasystem level. In order to calculate the results under different mobility conditions, a total of 18 scenarios were defined based on changes in vehicle speeds and the share of heavy vehicles (HV%) in the modal split. Subsequently, the scenarios were accurately modelled in the simulation software VISSIM and repeated 30 times with a simulation runtime of three hours. The results of the first approach confirmed the simultaneous effects of considering vehicle speed and HV % on fuel consumption and the amount of exhaust emissions generated. Furthermore, the sensitivity of exhaust emissions and fuel consumption to variations in vehicle speed was found to be much higher than HV %. In other words, the production of NOx and VOC emissions can be increased by up to 20 % by increasing the maximum speed of vehicles by 10 km/h. Conversely, increasing the HV percentage at the same speed does not seem to produce a significant change. Furthermore, increasing the speed from 30 km/h to 50 km/h increased CO emissions and fuel consumption by up to 33%. Similarly, a reduction in speed of 20 or 10 km/h with a 100% increase in HV resulted in a 40% and 27% decrease in exhaust emissions per seat, respectively. In the second approach, a novel methodology was proposed to estimate the number of brake particles in the case study. To achieve this goal, a downstream approach was proposed starting from the suprasystem level (microscopic traffic simulation models in VISSIM) and using a developed mathematical vehicle dynamics model at the system level to calculate the braking torques and angular velocities of the front and rear wheels, and proposes an artificial neural network (ANN) as a brake emission model, which has been appropriately trained and validated using emission data collected through more than 1000 experimental tribological tests on a reduced-scale dynamometer at the subsystem level (braking system). Consideration of this multi-level approach, from tribological to traffic-related aspects, is necessary for a realistic estimation of brake emissions. The proposed method was implemented on a targeted vehicle, a dominant SUV family car in the case study, considering real driving conditions. The relevant dynamic quantities of the targeted vehicle (braking torques and angular velocities of the wheels) were calculated based on the vehicle trajectory data such as speed and deceleration obtained from the traffic microsimulation models and converted into braking emissions via the artificial neural network. The total number of brake emissions emitted by the targeted vehicles was predicted for 10 iterations route by route and for the entire traffic network. The results showed that a large number of brake particles (in the order of billions of particles) are released by the targeted vehicles, which significantly affect the air quality in the case study. The results of this dissertation provide important information for policy makers to gain better insight into the rate of exhaust and brake emissions and fuel consumption in metropolitan areas and to understand their acute negative impacts on the health of citizens and commuters.

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Chen, Ruiwei. "Uncertainty quantification in the simulation of road traffic and associated atmospheric emissions in a metropolitan area." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1029/document.

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Ce travail porte sur la quantification d'incertitude dans la modélisation des émissions de polluants atmosphériques dues au trafic routier d'une aire urbaine. Une chaîne de modélisations des émissions de polluants atmosphériques est construite, en couplant un modèle d’affectation dynamique du trafic (ADT) avec un modèle de facteurs d’émission. Cette chaîne est appliquée à l’agglomération de Clermont-Ferrand (France) à la résolution de la rue. Un métamodèle de l’ADT est construit pour réduire le temps d’évaluation du modèle. Une analyse de sensibilité globale est ensuite effectuée sur cette chaîne, afin d’identifier les entrées les plus influentes sur les sorties. Enfin, pour la quantification d’incertitude, deux ensembles sont construits avec l’approche de Monte Carlo, l’un pour l’ADT et l’autre pour les émissions. L’ensemble d’ADT est évalué et amélioré grâce à la comparaison avec les débits du trafic observés, afin de mieux échantillonner les incertitudes
This work focuses on the uncertainty quantification in the modeling of road traffic emissions in a metropolitan area. The first step is to estimate the time-dependent traffic flow at street-resolution for a full agglomeration area, using a dynamic traffic assignment (DTA) model. Then, a metamodel is built for the DTA model set up for the agglomeration, in order to reduce the computational cost of the DTA simulation. Then the road traffic emissions of atmospheric pollutants are estimated at street resolution, based on a modeling chain that couples the DTA metamodel with an emission factor model. This modeling chain is then used to conduct a global sensitivity analysis to identify the most influential inputs in computed traffic flows, speeds and emissions. At last, the uncertainty quantification is carried out based on ensemble simulations using Monte Carlo approach. The ensemble is evaluated with observations in order to check and optimize its reliability

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Chen, Ruiwei. "Uncertainty quantification in the simulation of road traffic and associated atmospheric emissions in a metropolitan area." Electronic Thesis or Diss., Paris Est, 2018. http://www.theses.fr/2018PESC1029.

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Ce travail porte sur la quantification d'incertitude dans la modélisation des émissions de polluants atmosphériques dues au trafic routier d'une aire urbaine. Une chaîne de modélisations des émissions de polluants atmosphériques est construite, en couplant un modèle d’affectation dynamique du trafic (ADT) avec un modèle de facteurs d’émission. Cette chaîne est appliquée à l’agglomération de Clermont-Ferrand (France) à la résolution de la rue. Un métamodèle de l’ADT est construit pour réduire le temps d’évaluation du modèle. Une analyse de sensibilité globale est ensuite effectuée sur cette chaîne, afin d’identifier les entrées les plus influentes sur les sorties. Enfin, pour la quantification d’incertitude, deux ensembles sont construits avec l’approche de Monte Carlo, l’un pour l’ADT et l’autre pour les émissions. L’ensemble d’ADT est évalué et amélioré grâce à la comparaison avec les débits du trafic observés, afin de mieux échantillonner les incertitudes
This work focuses on the uncertainty quantification in the modeling of road traffic emissions in a metropolitan area. The first step is to estimate the time-dependent traffic flow at street-resolution for a full agglomeration area, using a dynamic traffic assignment (DTA) model. Then, a metamodel is built for the DTA model set up for the agglomeration, in order to reduce the computational cost of the DTA simulation. Then the road traffic emissions of atmospheric pollutants are estimated at street resolution, based on a modeling chain that couples the DTA metamodel with an emission factor model. This modeling chain is then used to conduct a global sensitivity analysis to identify the most influential inputs in computed traffic flows, speeds and emissions. At last, the uncertainty quantification is carried out based on ensemble simulations using Monte Carlo approach. The ensemble is evaluated with observations in order to check and optimize its reliability

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Johansson, Ingrid. "Simulation Studies of Impact of Heavy-Duty Vehicle Platoons on Road Traffic and Fuel Consumption." Licentiate thesis, KTH, Transportplanering, ekonomi och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-227996.

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The demand for road freight transport continues to grow with the growing economy, resulting in increased fossil fuel consumption and emissions. At the same time, the fossil fuel use needs to decrease substantially to counteract the ongoing global warming. One way to reduce fuel consumption is to utilize emerging intelligent transport system (ITS) technologies and introduce heavy-duty vehicle (HDV) platooning, i.e. HDVs driving with small inter-vehicle gaps enabled by the use of sensors and controllers. It is of importance for transport authorities and industries to investigate the effects of introducing HDV platooning. Previous studies have investigated the potential benefits, but the effects in real traffic, both for the platoons and for the surrounding vehicles, have barely been explored. To further utilize ITS and optimize the platoons, information about the traffic situation ahead can be used to optimize the vehicle trajectories for the platoons. Paper I presents a dynamic programming-based optimal speed control including information of the traffic situation ahead. The optimal control is applied to HDV platoons in a deceleration case and the potential fuel consumption reduction is evaluated by a microscopic traffic simulation study with HDV platoons driving in real traffic conditions. The effects for the surrounding traffic are also analysed. Paper II and Paper III present a simulation platform to assess the effects of HDV platooning in real traffic conditions. Through simulation studies, the potential fuel consumption reduction by adopting HDV platooning on a real highway stretch is evaluated, and the effects for the other vehicles in the network are investigated.
Efterfrågan på godstransporter på väg fortsätter att öka i takt med den växande ekonomin, vilket resulterar i ökad förbrukning av fossila bränslen och ökade utsläpp. Samtidigt behöver användandet av fossila bränslen minska för att motverka den pågående globala uppvärmningen. Ett sätt för att minska bränsleförbrukningen är att utnyttja den teknik kring intelligenta transportsystem som är under utveckling och introducera lastbilskonvojer, det vill säga lastbilar som använder sensorer och regulatorer för att kunna köra med korta avstånd mellan sig. För transportföretag och -myndigheter är det viktigt att undersöka effekterna av att införa lastbilskonvojkörning. Tidigare studier har undersökt de möjliga fördelarna, men effekterna vid körning i trafik, både för konvojerna och för omgivande fordon, är outforskade. För att ytterligare utnyttja intelligenta transportsystem och optimera konvojerna kan information om trafiksituationen längre fram på vägen användas för att optimera konvojernas körning. Artikel I presenterar en optimal hastighetsregulator baserad på dynamisk programmering och som inkluderar information om trafiksituationen längre fram. Den optimala regulatorn appliceras på lastbilskonvojer under ett inbromsningsscenario och den potentiella minskningen i bränsleförbrukning utvärderas genom en mikroskopisk trafiksimuleringsstudie där lastbilskonvojerna kör i verkliga trafikförhållanden. Effekterna för omgivande fordon är också analyserade.Artikel II och artikel III presenterar en simuleringsplattform för att utvärdera effekterna av lastbilskonvojkörning i verkliga trafikförhållanden. Genom simuleringsstudier analyseras den potentiella bränsleförbrukningsminskningen då lastbilskonvojer körs på en verklig motorvägssträcka och effekterna för de övriga fordonen på vägen undersöks.

QC 20180516

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Santos, Maria Izabel dos. "Identifying active factors by a fractioned factorial experimental design and simulation in road traffic accidents." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18143/tde-28092017-091715/.

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Researchers around the world are constantly seeking for a quick, inexpensive and easy to use way to understand road traffic deaths. This study proposes the use of multibody (MBS) simulation, using a virtual driver, associated to fractional factorial experiments to identify active factors in road traffic accidents. The objectives of this work were to: (i) use DOE to show a more structured direction on the studies of road safety and (ii) investigate possible vehicle state variables to monitor vehicle dynamic stability. The first experiment was a quarter fraction It was designed based on an accident database of a Brazilian Federal Highway. Seven factors were considered (curve radius, path profile, path condition, virtual driver skill, speed, period of the day and car load) and 3 replicates were performed per treatment. Speed and friction coefficient were defined randomly for each treatment, within the defined range for each level. 42 accidents were observed in 96 events. Speed had shown the highest influence on the occurrence, followed by curve radius, period of the day and some second order interactions. The second experiment was based on the results of first one. A half fraction factorial design with five factors (curve radius, car load, virtual driver skill, period of the day and speed), with 14 replicates per treatment, was performed. Speed was defined randomly as per previous experiment. 96 accidents were observed in 224 events. Speed had the highest influence on the occurrence of accidents, followed by the period of the day, curve radius, virtual driver skill and second order interactions. Speed is also pointed by World Health Organization as one of the key factors for the occurrence of accidents. The study indicates that a well-designed experiment with a representative vehicle model can show a direction for further researches. At last, roll angle, yaw rate and displacement of the car on the road are variables suggested to be monitored in experiments using simulation to identify vehicle\'s instability.
Pesquisadores do mundo estão constantemente buscando uma maneira rápida, barata e fácil de usar para entender acidentes de trânsito. O presente estudo propõe o uso de simulação, condutor virtual e experimentos fatoriais para a identificação de fatores ativos em acidentes rodoviários. Os objetivos deste trabalho foram: utilizar experimentos planejados, associado a simulação para obter uma direção para estudos futuros e investigar possíveis variáveis de estado do veículo a serem usadas para monitorar sua estabilidade dinâmica. Para tal, foi utilizado um modelo completo de veículo validado e dados reais de acidentes de um determinado trecho de rodovia brasileira. O primeiro experimento baseou-se em um banco de dados de acidentes de uma rodovia Federal brasileira. Optou-se por fracionar o experimento, utilizando um quarto de fração. Sete fatores foram considerados (raio da curva, perfil da pista, condição da pista, habilidade do condutor virtual, velocidade, período do dia e carga do carro) e foram realizadas três réplicas por tratamento. Velocidade e coeficiente de atrito foram utilizados como fontes de variação do experimento: para cada tratamento, e dentro do intervalo definido para cada nível, ambos foram definidos aleatoriamente. Em 54 dos 96 eventos foram observou-se acidentes. Velocidade, raio da curva, período do dia e algumas interações de segunda ordem foram os fatores com maior influência na ocorrência de acidentes. O segundo experimento utilizou como dado de entrada os resultados obtidos no experimento anterior. O experimento foi fracionado, meia fração, com cinco fatores (raio da curva, carga do carro, habilidade do motorista virtual, período do dia e velocidade). Foram realizadas 14 réplicas por tratamento, e a velocidade foi mantida como fonte de variação. Em 96 dos 224 eventos foram observados acidentes. Velocidade teve maior influência na ocorrência de acidentes, seguida por período do dia, raio da curva, habilidade do motorista virtual e interações de segunda ordem. A velocidade também é apontada pela Organização Mundial da Saúde como um dos fatores-chave para a ocorrência de acidentes. Isto indica que um experimento bem planejado, com um modelo de veículo representativo, pode apontar uma direção a ser seguida em pesquisas futuras. Por último é sugerido o monitoramento do ângulo de rolagem (roll angle), da taxa de guinada (yaw rate), e do deslocamento lateral do carro na pista para identificar instabilidades no veículo quando são utilizadas simulações.

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Eriksson, Olle. "Sensitivity and Uncertainty Analysis Methods : with Applications to a Road Traffic Emission Model." Doctoral thesis, Linköping : Linköpings universitet, Deparment of Mathematics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8315.

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Tchappi, haman Igor. "Dynamic Multilevel and Holonic Model for the Simulation of a Large-Scale Complex System with Spatial Environment : Application to Road Traffic Simulation." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCA004.

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De nos jours, avec l’émergence d’objets et de voitures connectés, les systèmes de trafic routier deviennent de plus en plus complexes et présentent des comportements hiérarchiques à plusieurs niveaux de détail. L'approche de modélisation multiniveaux est une approche appropriée pour représenter le trafic sous plusieurs perspectives. Les modèles multiniveaux constituent également une approche appropriée pour modéliser des systèmes complexes à grande échelle comme le trafic routier. Cependant, la plupart des modèles multiniveaux de trafic proposés dans la littérature sont statiques car ils utilisent un ensemble de niveaux de détail prédéfinis et ces représentations ne peuvent pas commuter pendant la simulation. De plus ces modèles multiniveaux considèrent généralement seulement deux niveaux de détail. Très peu de travaux se sont intéressés à la modélisation dynamique multiniveau de trafic.Cette thèse propose un modèle holonique multiniveau et dynamique du trafic à grande échelle.La commutation dynamique des niveaux de détail lors de l’exécution de la simulation permet d’adapter le modèle aux contraintes liées à la qualité des résultats ou aux ressources de calcul disponibles.La proposition étend l'algorithme DBSCAN dans le contexte des systèmes multi-agents holoniques. De plus, une méthodologie permettant la commutation dynamique entre les différents niveaux de détail est proposée. Des indicateurs multiniveaux basés sur l'écart type sont aussi proposés afin d'évaluer la cohérence des résultats de la simulation
Nowadays, with the emergence of connected objects and cars, road traffic systems become more and more complex and exhibit hierarchical behaviours at several levels of detail. The multilevel modeling approach is an appropriate approach to represent traffic from several perspectives. Multilevel models are also an appropriate approach to model large-scale complex systems such as road traffic. However, most of the multilevel models of traffic proposed in the literature are static because they use a set of predefined levels of detail and these representations cannot change during simulation. Moreover, these multilevel models generally consider only two levels of detail. Few works have been interested on the dynamic multilevel traffic modeling.This thesis proposes a holonic multilevel and dynamic traffic model for large scale traffic systems. The dynamic switching of the levels of detail during the execution of the simulation allows to adapt the model to the constraints related to the quality of the results or to the available computing resources.The proposal extends the DBSCAN algorithm in the context of holonic multi-agent systems. In addition, a methodology allowing a dynamic transition between the different levels of detail is proposed. Multilevel indicators based on standard deviation are also proposed in order to assess the consistency of the simulation results

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Khanta, Pothu Raju. "Evaluation of traffic simulation models for work zones in the New England area." Connect to this title, 2008. http://scholarworks.umass.edu/theses/184/.

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Mahbub, S. M. Parvez Bin. "Impact of urban traffic and climate change on water quality from road runoff." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/47139/1/Parvez_Mahbub_Thesis.pdf.

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Urban traffic and climate change are two phenomena that have the potential to degrade urban water quality by influencing the build-up and wash-off of pollutants, respectively. However, limited knowledge has made it difficult to establish any link between pollutant buildup and wash-off under such dynamic conditions. In order to safeguard urban water quality, adaptive water quality mitigation measures are required. In this research, pollutant build-up and wash-off have been investigated from a dynamic point of view which incorporated the impacts of changed urban traffic as well as changes in the rainfall characteristics induced by climate change. The study has developed a dynamic object classification system and thereby, conceptualised the study of pollutant build-up and wash-off under future changes in urban traffic and rainfall characteristics. This study has also characterised the buildup and wash-off processes of traffic generated heavy metals, volatile, semi-volatile and non-volatile hydrocarbons under dynamic conditions which enables the development of adaptive mitigation measures for water quality. Additionally, predictive frameworks for the build-up and wash-off of some pollutants have also been developed.

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BOTTERO, MARCO. "Multi-scale modelling and simulation of ITS applications for energy optimisation in road traffic and transport systems." Doctoral thesis, Politecnico di Torino, 2015. http://hdl.handle.net/11583/2606361.

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The main focus of this work is on a motorway application, intended at traffic flow optimisation in terms of throughput and energy consumptions. Motorways can be considered as the backbone of the transportation system of a Region or a Country, they are capable to ensure high throughput under standard traffic conditions, but they tend to become unstable in case of bottlenecks generated by unexpected accidents or unsustainable traffic demand. The time and energy loss in these circumstances can be very relevant if compared with the total energy and time taken by the travellers to complete their trip. After some initial considerations related to the ITS concept and the reasons behind the choice of this specific matter to study (Section 1), the work begins with an overview of existing traffic monitoring and control technologies (Section 2). Particularly focusing on the monitoring needs of ITS, this first part develops some filtering tools intended to adjust measurements from real traffic monitoring systems. The central part of the thesis (Sections 3, 4, and 5) deals with the modelling aspects, with particular reference to motorway applications and to the developments needed to address energy consumption reduction in congested traffic flows. To conclude, Section 7 presents some complementary applications, in which the same concepts are applied to different scenarios, belonging to the urban and inter-urban domain.

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Olstam, Johan. "Simulation of Surrounding Vehicles in Driving Simulators." Doctoral thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17453.

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Driving simulators and microscopic traffic simulation are important tools for making evaluations of driving and traffic. A driving simulator is de-signed to imitate real driving and is used to conduct experiments on driver behavior. Traffic simulation is commonly used to evaluate the quality of service of different infrastructure designs. This thesis considers a different application of traffic simulation, namely the simulation of surrounding vehicles in driving simulators. The surrounding traffic is one of several factors that influence a driver's mental load and ability to drive a vehicle. The representation of the surrounding vehicles in a driving simulator plays an important role in the striving to create an illusion of real driving. If the illusion of real driving is not good enough, there is an risk that drivers will behave differently than in real world driving, implying that the results and conclusions reached from simulations may not be transferable to real driving. This thesis has two main objectives. The first objective is to develop a model for generating and simulating autonomous surrounding vehicles in a driving simulator. The approach used by the model developed is to only simulate the closest area of the driving simulator vehicle. This area is divided into one inner region and two outer regions. Vehicles in the inner region are simulated according to a microscopic model which includes sub-models for driving behavior, while vehicles in the outer regions are updated according to a less time-consuming mesoscopic model. The second objective is to develop an algorithm for combining autonomous vehicles and controlled events. Driving simulators are often used to study situations that rarely occur in the real traffic system. In order to create the same situations for each subject, the behavior of the surrounding vehicles has traditionally been strictly controlled. This often leads to less realistic surrounding traffic. The algorithm developed makes it possible to use autonomous traffic between the predefined controlled situations, and thereby get both realistic traffc and controlled events. The model and the algorithm developed have been implemented and tested in the VTI driving simulator with promising results.

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Wyatt, David William. "Assessing micro-scale carbon dioxide (CO2) emission on UK road networks using a coupled traffic simulation and vehicle emission model." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/19238/.

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With an increasing divergence between test certified vehicle emission and on-road vehicle emission, the accurate appraisal of real-world vehicle emission has arguably never been more important. This research advances the development, calibration and validation of a coupled traffic micro-simulation and instantaneous emission model. A portable emission measurement system (PEMS) data set was used to quantify the real-world CO2 emission of a passenger car through an urban traffic network, in Leeds (UK), over the diurnal range of traffic flow conditions. Utilising these data, analysis was conducted to assess the accuracy of CO2 micro-scale emission estimates by four emissions models; the Emissions Factors Toolkit (EFT), the Handbook Emission Factors for Road Transport (HBEFA); the Motor Vehicle Emission Simulator (MOVES); and the Passenger car and Heavy duty Emission Model (PHEM). The results demonstrated the strength of power based models over average speed based methods. The study identified the influence that road grade can have on the micro-scale modelling of exhaust CO2 emission and developed a novel methodology to incorporate grade into the modelling. A coupled traffic simulation and instantaneous emission model was developed for the study area, using the simulation tool AIMSUN and the emission model PHEM. The model was separately calibrated and validated for five time periods. Parameters within the coupled model, such as the vehicle fleet and vehicle dynamics were customised for the specific study area and time period. The research demonstrated the ability of the AIMSUN-PHEM model to deliver an accurate appraisal of on-road CO2 emission for each time period and its capacity to generate a range of emission factors from those of a single vehicle to those of the entire fleet. This work confirms that a properly calibrated traffic simulation emission model can provide an effective method for conducting high resolution analysis of vehicle emission in a network.

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Rahman, Mustazibur. "Management of City Traffic, Using Wireless Sensor Networks with Dynamic Model." Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/30916.

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Road network of a region is of a paramount importance in the overall development. Management of road traffic is a key factor for the city authority and reducing the road traffic congestion is a significant challenge in this perspective. In this thesis, a Wireless Sensor Network (WSN) based road-traffic monitoring scheme with dynamic mathematical traffic model is presented that will not necessarily include all adjacent intersections of a block; rather the important major intersections of a city. The objective of this scheme is to reduce the congestion by re-routing the vehicles to better performing road-segments by informing the down-stream drivers through broadcasting the congestion information in a dedicated radio channel. The dynamic model can provide with the instantaneous status of the traffic of the road-network. The scheme is a WSN based multi-hop relay network with hierarchical architecture and composed of ordinary nodes, Cluster-Head nodes, Base Stations, Gateway nodes and Monitoring and Control Centers (MCC) etc. Through collecting the traffic information, MCC will check the congestion status and in defining the congestion, threshold factors have been used in this model. For the congested situation of a road-segment, a cost function has been defined as a performance indicator and estimated using the weight factors (importance) of these selected intersections. This thesis considered a traffic network with twelve major intersections of a city with four major directions. Traffic arrivals in these intersections are assumed to follow Poisson distribution. Model was simulated in Matlab with traffic generated through Poisson Random Number Generator and cost function was estimated for the congestion status of the road-segments over a simulation period of 1440 minutes starting from midnight. For optimization purpose we adopted two different approaches; in the first approach, performance of the scheme was evaluated for all threshold factor values iteratively one at a time, applying a threshold factor value to define threshold capacities of all the road segments; traffic was generated and relative cost has been estimated following the model specifications with the purpose of congestion avoidance. In the second approach, different values of threshold factor have been used for different road segments for determining the optimum set-up, and exhaustive search technique has been applied with a smaller configuration in order to keep computations reachable. Simulation results show the capacity of this scheme to improve the traffic performance by reducing the congestion level with low congestion costs.

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Aronsson, Karin F. M. "Speed characteristics of urban streets based on driver behaviour studies and simulation." Doctoral thesis, Stockholm : Division of transport och logistics, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4259.

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COCONEA, LAURA DANIELA. "Analysis, simulation and testing of ITS applications based on wireless communication technologies." Doctoral thesis, Politecnico di Torino, 2015. http://hdl.handle.net/11583/2598394.

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Intelligent Transportation Systems (ITS) aim to improve road transport safety and efficiency, to manage road networks in the interest of the society and to provide real time responses to events. In order to reach these goals, real time feedback to the drivers is expected through the integration of telecommunications, sensing and information technologies with transport engineering. Wireless communication technologies, that have been used in industrial applications for more than 30 years, play a crucial role in ITS, as based on the concept of multiple devices (on both vehicle and infrastructure side) interconnected in different ways. Connectivity, in tandem with sensing technologies, is fuelling the innovations that will inevitably lead to the next big opportunity for road transport: autonomous vehicles. Therefore, this study has investigated - through analysis, simulation and field testing – on applications based on wireless communication technologies meant to support both Data acquisition and Data diffusion as fundamental aspects/ phases in ITS, where data is widely individuated as being the key element.

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Dostál, Martin. "Simulátor městské dopravy." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2016. http://www.nusl.cz/ntk/nusl-255312.

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This thesis is focused on microsimulation of city traffic, specifically a small city circuit in Brno. The thesis describes approaches for solving the problem of road network representation and presents basic methods and models needed for traffic simulation on the level of individual vehicles control as well as on the level of simulator control. In the case of more possible solutions to the given problem, the features and suitability of these solutions are compared. In the practical part of the thesis, the structure of the proposed simulator is presented with all the dependencies among individual submodels, along with the description of implementation details related to the individual parts.

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Ameli, Mostafa. "Heuristic Methods for Calculating Dynamic Traffic Assignment Simulation-based dynamic traffic assignment: meta-heuristic solution methods with parallel computing Non-unicity of day-to-day multimodal user equilibrium: the network design history effect Improving traffic network performance with road banning strategy: a simulation approach comparing user equilibrium and system optimum." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSET009.

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Les systèmes de transport sont caractérisés de manière dynamique non seulement par des interactions non linéaires entre les différents composants, mais également par des boucles de rétroaction entre l'état du réseau et les décisions des utilisateurs. En particulier, la congestion du réseau impacte à la fois la répartition de la demande locale en modifiant les choix d’itinéraire et la demande multimodale globale. Selon les conditions du réseau, ils peuvent décider de changer, par exemple, leur mode de transport. Plusieurs équilibres peuvent être définis pour les systèmes de transport. L'équilibre de l'utilisateur correspond à la situation dans laquelle chaque utilisateur est autorisé à se comporter de manière égoïste et à minimiser ses propres frais de déplacement. L'optimum du système correspond à une situation où le coût total du transport de tous les utilisateurs est minimal. Dans ce contexte, l’étude vise à calculer les modèles de flux d'itinéraires dans un réseau prenant en compte différentes conditions d’équilibre et à étudier l’équilibre du réseau dans un contexte dynamique. L'étude se concentre sur des modèles de trafic capables de représenter une dynamique du trafic urbain à grande échelle. Trois sujets principaux sont abordés. Premièrement, des méthodes heuristiques et méta-heuristiques rapides sont développées pour déterminer les équilibres avec différents types de trafic. Deuxièmement, l'existence et l'unicité des équilibres d'utilisateurs sont étudiées. Lorsqu'il n'y a pas d'unicité, la relation entre des équilibres multiples est examinée. De plus, l'impact de l'historique du réseau est analysé. Troisièmement, une nouvelle approche est développée pour analyser l’équilibre du réseau en fonction du niveau de la demande. Cette approche compare les optima des utilisateurs et du système et vise à concevoir des stratégies de contrôle afin de déplacer la situation d'équilibre de l'utilisateur vers l'optimum du système
Transport systems are dynamically characterized not only by nonlinear interactions between the different components but also by feedback loops between the state of the network and the decisions of users. In particular, network congestion affects both the distribution of local demand by modifying route choices and overall multimodal demand. Depending on the conditions of the network, they may decide to change for example their transportation mode. Several equilibria can be defined for transportation systems. The user equilibrium corresponds to the situation where each user is allowed to behave selfishly and to minimize his own travel costs. The system optimum corresponds to a situation where the total transport cost of all the users is minimum. In this context, the study aims to calculate route flow patterns in a network considering different equilibrium conditions and study the network equilibrium in a dynamic setting. The study focuses on traffic models capable of representing large-scale urban traffic dynamics. Three main issues are addressed. First, fast heuristic and meta-heuristic methods are developed to determine equilibria with different types of traffic patterns. Secondly, the existence and uniqueness of user equilibria is studied. When there is no uniqueness, the relationship between multiple equilibria is examined. Moreover, the impact of network history is analyzed. Thirdly, a new approach is developed to analyze the network equilibrium as a function of the level of demand. This approach compares user and system optimums and aims to design control strategies in order to move the user equilibrium situation towards the system optimum

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Sousa, Janailson Queiroz. "Modelagem microscÃpica aplicada na avaliaÃÃo do desempenho da seguranÃa viÃria em interseÃÃes urbanas." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9059.

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nÃo hÃ
A modelagem microscÃpica do fluxo de veÃculos na infraestrutura viÃria urbana tem se constituÃdo uma potencial ferramenta para a anÃlise do desempenho da seguranÃa viÃria (DSV) frente aos tradicionais mÃtodos de anÃlise com base nos estudos observacionais. Para consolidar essa abordagem existem desafios prÃticos e metodolÃgicos que foram tratados como objetivos nesta pesquisa, dentre os quais se destacam: (i) a identificaÃÃo de indicadores proxy eficientes para as anÃlises de seguranÃa nesse ambiente; (ii) a anÃlise dos algoritmos de microssimulaÃÃo quanto a sua eficÃcia de representaÃÃo dos processos de conduÃÃo no meio urbano, (iii) a definiÃÃo de um procedimento sistemÃtico de estimaÃÃo do DSV com o uso de microssimuladores de trÃfego e (iv) a validaÃÃo dos indicadores sintÃticos usados para medir o DSV. Diante deste contexto, esta pesquisa tem como objetivo geral apresentar uma contribuiÃÃo metodolÃgica para a utilizaÃÃo da microssimulaÃÃo de trÃfego nas anÃlises do DSV no processo de planejamento tÃtico operacional dos sistemas de transporte com foco nas interseÃÃes urbanas. O procedimento metodolÃgico proposto considerou a realizaÃÃo de cinco etapas: 1) seleÃÃo e caracterizaÃÃo do local de estudo, 2) codificaÃÃo do local no microssimulador, 3) planejamento da simulaÃÃo, 4) calibraÃÃo e validaÃÃo do modelo e 5) estimaÃÃo dos indicadores. A aplicaÃÃo do procedimento considerou trÃs interseÃÃes semaforizadas da cidade de Fortaleza, utilizando a plataforma de microssimulaÃÃo de trÃfego VISSIM. Os resultados alcanÃados indicaram que foi possÃvel estimar o DSV com relativo nÃvel de confianÃa e um procedimento complementar de validaÃÃo dos indicadores revelou um nÃvel de consistÃncia entre o nÃmero estimado de conflitos de interaÃÃes longitudinais e o nÃmero observado de colisÃes traseiras observadas em campo.
The microscopic modeling of traffic flow in urban road infrastructure has proven to be a potential tool for analyzing the performance of road safety (DSV) compared to traditional methods of analysis based on observational studies. To consolidate this approach there are practical and methodological challenges that have been treated as objectives in this research, among which are: (i) the identification of efficient synthetic indicators for the analysis of safety in this environment, (ii) the analysis of the microscopic algorithms and their effectiveness in the representation of the driving processes in urban areas, (iii) the definition of a systematic procedure for estimating the DSV using a microscopic platform and (iv) concerning the validation of synthetic indicators used to measure the DSV. Given this context, this research intended to provide a general methodological contribution to the use of microscopic traffic simulators for the analysis of the DSV in tactical and operational transportation systems planning process with focus on urban intersections. The proposed methodological procedure considered the completion of five steps: 1) selection and site characterization study, 2) coding the site in microsimulator 3) planning of the simulation, 4) calibration and validation of the model and 5) estimation of the indicators. The procedure considered three signalized intersections in the city of Fortaleza, using VISSIM Â as simulation platform. The results indicated that it was possible to estimate the DSV with relative confidence level and a complementary procedure for validation of the indicators showed a consistent level of consistency between the estimated number of conflicts of longitudinal interactions and observed number of rear end collisions observed in the field.

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Hequn, Zhang, and Wang Rui. "SIMULATION-BASED PERFORMANCE COMPARISONS OF GEOCAST ROUTING PROTOCOLS." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-25768.

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Intelligent Transportation System (ITS) is the main research domain for making road transport safer and more comfortable. For the sake of increasing the benefits of ITS, projects about Inter-Vehicle Communication (IVC) system have been proposed to make communications among vehicles possible, to exchange traffic information and avoid accidents. In order to create communication network among vehicles or between vehicles and infrastructure, Vehicular Ad hoc Networks (VANETs) has been proposed. Many applications in VANETs need to send messages to vehicles within a specific geographic region. This behavior is called geocast and this specific geographic region is called the Zone of Relevance (ZOR). Some routing protocols which are related to Geocast have been proposed in literature for VANETs. So it is significant to evaluate and compare the performance of these known Geocast routing protocols. In this thesis, categories of the routing protocols, as well as communication forwarding schemes are introduced. The routing protocols in VANETs are also summarized and compared. In order to evaluate the performance of these protocols, the evaluation methods are proposed and then a Geocast routing simulator is designed and used to simulate the Geocast network environment and several Geocast routing protocols.

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Ramamonjisoa, David. "Architecture de copilotage et de contrôle d'exécution basée sur un système expert temps réel." Compiègne, 1993. http://www.theses.fr/1993COMP574S.

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Le développement croissant du trafic routier, le besoin de confort et d'information des conducteurs et l'exigence générale d'une plus grande sécurité sont actuellement le grand souci des laboratoires de recherches et constructeurs automobiles des pays industrialisés. Le projet européen PROMETHEUS a pour objectif d'améliorer la sécurité de la circulation routière de 30% et l'efficacité de 20%. Dans le cadre de ce projet, une application de système d'aide au copilotage a été réalisée avec la mise au point d'un système de contrôle d'exécution des manoeuvres et de surveillance des environnements. Des outils à base de techniques d'intelligence artificielle et d'automatique ont été développés pour la réalisation d'un tel système. La démarche suivie est de spécifier une architecture de contrôle pour diminuer le temps de réponse du système et pour structurer les tâches de façon modulaire. Les modules de décision et de contrôle ont été développés à l'aide d'un système expert temps réel SUPER-TR. Une phase de simulation a permis de tester la rapidité et d'évaluer la base de connaissances du système. La mise à jour des stratégies et des modèles utilisés dans le copilotage est également effectuée au cours de cette phase.

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Emery, Justin. "La ville sous électrodes : de la mesure à l'évaluation de la pollution atmosphérique automobile. : vers une simulation multi-agents du trafic routier en milieu urbain." Thesis, Dijon, 2016. http://www.theses.fr/2016DIJOL018/document.

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À partir des enquêtes, le trafic n’est pas une donnée, mais il est plutôt construit à partir d’hypothèses portant sur les relations entre des origines et des destinations. En vue de reconstruire un trafic routier plus proche de la mesure, et sur un ensemble de tronçons routiers plus important, il apparait alors intéressant de partir de données de comptages issues de capteurs urbains. Notre postulat de départ part de ce constat. L’insertion de ces données d’observations du trafic routier fournit l’opportunité d’expérimenter les potentiels d’exploitations des capteurs pour estimer les niveaux de Pollution Atmosphérique Automobile (PAA) à l’échelle intraurbaine. Cependant, il est alors nécessaire de modifier la nature de la mesure en vue d’extraire une information sur la circulation routière, ce qui a été envisagé ici à travers la construction d’un modèle de simulation multi-agents. D’une manière plus générale, en partant de la donnée, c’est une démarche de construction de la connaissance sur les émissions de PAA qui est abordée tout au long de ce travail. La mise en œuvre de la démarche de modélisation SCAUP (Simulation multi-agents à partir de Capteurs Urbains pour la Pollution atmosphérique automobile) a été réalisée en trois temps : 1. En se focalisant sur les dispositifs de quantification du trafic routier à travers les capteurs urbains ; 2. En proposant une démarche de modélisation et de simulation de ces données pour le trafic routier ; 3. En se rattachant aux référentiels nationaux utilisés par les AASQA pour le calcul des émissions de PAA. L’ensemble se lie et s’intègre au sein d’une matrice technique qui constitue la colonne vertébrale de ce manuscrit à travers trois dispositifs interdépendants : la quantification, la modélisation et l’évaluation. Ce travail s’inscrit dans une démarche expérimentale de simulation du trafic routier pour le calcul des émissions de PAA. Parrainé par l’AASQA locale ATMOSF’AIR BOURGOGNE, il s’inscrit aussi dans une optique de recherche appliquée en appui de ces organismes en charge de la surveillance de la qualité de l’air. À l’heure où le big data entre dans de nouveaux questionnements quant aux capacités des chercheurs à en extraire une connaissance, nous proposons une démarche géographique en vue de replacer la donnée au centre d’une démarche de simulation originale du trafic routier (data-driven)
Based on surveys, traffic is constructed from assumptions about the relationship between origins and destinations. In order to rebuild a road traffic wich would be closer to observation and on a wider set of road sections, it appears interesting to use counting data from urban sensors : this is our starting point of view. The insertion of these in-situ dataset in the road traffic measurement provides the opportunity to experience the potential of sensors to estimate Traffic Air Pollution (TAP) levels at the intraurban scale. However, this requires to change the nature of these estimation, here through the construction of a model of multi-agents simulation, in order to extract more information on the road traffic. More generally, this work can be seen as a a knowledge building approach on TAP emisssions which is discussed throughout this work. The implementation of the SCAUP (multi-agent simulation from Urban sensors for traffic air pollution) approach was developped in three stages: 1. Focusing on the quantification of road traffic devices through urban sensors; 2. Proposing a modeling approach for road traffic data simulation ; 3. Using as a reference the national framework used by AASQA to calculate RTA emissions. All is integrated within a technical matrix that forms the spine of the manuscript through three interrelated systems: quantification, modeling and evaluation. This work is part of an experimental approach dedicated to the calculation of TAP emissions based on traffic simulations. Sponsored by the ATMOSF’AIR BOURGOGNE local AASQA, this work could also be used in an operational mode for these organizations in charge of the air quality monitoring. At a time when the big data enters into new questions about the ability of researchers to extract knowledge, we propose a geographical approach that enables to replace the data in the center of an original road traffic simulation approach (data- driven)

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Rickardsson, Johan. "A Study of Traffic Capacity with Regards to Heavy vehicle Share and Level of Service through Microsimulation." Thesis, KTH, Transportplanering, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302528.

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The 2+1-road is a specific three lane road which aims to increase the safety of the predecessor 13 meter wide four lane roads. As a lane is removed and a weaving section is introduced the capacity is severely lowered, sometimes halved. A very demanding part of the traffic system with regards to capacity are heavy vehicles, especially in conjunction with the 2+1-roads. However, exactly how the share of heavy vehicles impacts the traffic system with regards to 2+1 roads and freeways is not previously studied, which grants the opportunity of this work. The work has been carried out in connection with an assignment from The Swedish Transport Administration of analyzing the E4 going north from Gävle. This study analyzes how the share of heavy vehicles and level of service affect the speed on the two types of roads. The Swedish Transport Administration currently bases their current relationships on speed, capacity, and level of service on a share of heavy vehicles of 12%, which may give slightly wrong results depending on which system is being analyzed. The study has been carried out through micro simulation, which is a method that is very dependent on what data it is given, such as behavioral parameters and other input. The results of the study show how the relationship between share of heavy vehicles and level of service affect the speed, and that the 2+1-roads are highly dependent on the share of heavy vehicles, whereas the freeways have much larger tolerances.
Den mötesfria vägen (s.k. 2+1-väg) tillkom på 90-talet och gav upphov till mycket mer trafiksäkra vägar än sina föregångare 13-metersvägarna från mitten av 1900-talet. Till följd av säkerhetsökningen kom uppoffringar i kapacitet i och med vävningssträckor, som mer än halverar kapaciteten i jämförelse med en tvåfilig väg. En mycket kapacitetskrävande del av trafiksystemet är lastbilar, framförallt i dessa vävningssträckor. Men exakt hur lastbilsandelar påverkar systemet är inte riktigt bearbetat än, vilket ger upphov till detta examensarbete. Studien har utförts i samband med ett uppdrag från Trafikverket angående simulering av E4:an norr om Gävle. Detta examensarbete granskar alltså hur lastbilsandelen och belastningsgraden påverkar punkthastigheten på de två vägtyperna mötesfri väg och motorväg. Trafikverket baserar sina effektsamband på en lastbilsandel på 12 %, vilket kan ge både för låga och för höga värden beroende på vilken plats som man granskar. Arbetet har genomförts med hjälp av mikrosimuleringsmodeller, vilka är mycket beroende av vilka parametrar och indata de får. Resultatet av studien visar hur punkthastigheten beror på lastbilsandel och belastningsgrad, och visar på att de mötesfria vägarna är mycket beroende av lastbilsandelen, medan motorvägar har betydligt större tolerans.

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Kačic, Matej. "Systém řízení dopravy." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-237223.

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Main goal of this thesis is to create an application which can do a simulation of model of road traffic system based on reality and can handle to manage signal control based on the proposed algorithm so that the road traffic should have a great performance and system should have a maximum throughput. It describes a simulation model, different approaches in design of algorithm for management of the road traffic system and decribes in detail evolutionary approach for optimalization system of control crossroads.

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Touhbi, Saâd. "Élaboration d’un modèle multi-agents pour la génération synthétique de trafic : application à la mobilité urbaine de la ville de Marrakech." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS326.

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La génération de trafic est un processus indispensable dans la simulation du trafic. Ce processus permet de définir une série d’arrivées des véhicules dans une route. Cette série est prouvée aléatoire depuis 1930. Toutefois, sa distribution reflète à un niveau le comportement de conduite. L’objectif de notre thèse est de mettre en place un outil de génération de trafic permettant de définir le point d’arrivée du véhicule dans une route, identifier le choix de type du véhicule, définir son temps d’arrivée, et lui affecter une vitesse initiale. Une première étape faite dans ce sens est la modélisation d’arrivée, particulièrement le TIV, en mettant en place un protocole d’analyse de cette variable en quatre étapes : traitement des données d’arrivée des véhicules et calcul de la variable TIV, définir des échantillons représentant différents niveaux de trafic, le choix des modèles probabilistes et estimation des paramètres, comparaison des modèles estimés et les données empiriques. Une application numérique est effectuée sur quatre routes à trois voies chacune interrompue par un feu de signalisation à la ville de Marrakech. On en conclut que Le modèle de Pareto IV est non rejeté pour les différents niveaux de trafic. Le modèle Exponentiel est prouvé inadéquat dans les différents niveaux de trafic. Le modèle Log-Normal et le modèle de Pearson type III sont adéquats pour des niveaux de trafic intermédiaire et élevé. Ces résultats ont permis de tester l’utilisabilité de notre outil de génération de trafic sous différentes modalités. L’outil permet de générer un niveau trafic cohérent avec celui désiré. Une première intégration a été faite pour la simulation MarrakAir permettant d’estimer les polluants automobiles en se basant sur le trafic. Ceci afin d’éliminer la nécessité d’avoir des données ponctuelles sur l’arrivée des véhicules
Traffic generation is an important process in traffic simulation. It defines a series of vehicle arrival at a road. This series is proven to be random since 1930. However, its distribution explains at a level the behavior of the motorists. The goal of this thesis is to establish a traffic generation toolbox to produce a series of vehicle arrival characterized by their entry point, their type, arrival time and their initial speed. A first step was to establish an analysis protocol for the time headway (TH) of the arriving vehicles consisting of four steps : (i) data processing and calculating TH, (ii) sampling of data according to different levels of traffic, (iii) model choice and estimation, (iv) and the comparison of the estimated models and the empirical data. The application of the latter on four roads with three lanes interrupted by a signalized intersection showed that : The Pareto IV model is not rejected for all levels of traffic in these roads, the Exponential model is proven to be inadequate for all levels of traffic, the Log-Normal and Pearson III are best suited for intermediate to high levels of traffic. These results helped in testing the traffic generation toolbox proving that it generates coherent level of traffic compared to the desired configuration. The latter was integrated in the simulation MarrakAir that estimated the level of pollution based on traffic. This was done to eliminate the necessity to have punctual data from sensors about vehicle arrivals

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Tian, Bin. "Data dissemination protocols and mobility model for VANETs." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22739/document.

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Pendant les deux dernières décennies, les technologies de réseaux ad-hoc de véhicules (VANETs : Vehicular Ad-Hoc Networks) ont été développées sous l’impulsion du monde de la recherche comme de l’industrie, étant donnés les liens des VANETs avec la sécurité routière, l’internet des objets (IoT/WoT : Internet of Things/Web of Things) pour les systèmes de transport intelligents (ITS : Intelligent Transportation Systems), les villes intelligentes et les villes vertes. Composant essentiel des VANETs, les protocoles de communication inter-véhicules (IVC : Inter-Vehicle Communication) font face à des défis techniques, en particulier à cause de la diversité des applications dans lesquelles ils sont impliqués. Dans cette thèse, après une présentation des VANETs et de l’état de l’art des IVC, nous proposons un protocole de dissémination de données, TrAD, conçu pour diffuser de manière efficiente des messages d’une source vers les véhicules présents dans la zone d’intérêt (ROI : Range of Interest). TrAD se base sur les états du trafic routier et du trafic réseau pour adapter localement la stratégie et les paramètres de transmission des données afin d’optimiser les performances des applications qui l’utilisent. De plus, un algorithme de classification des clusters locaux de véhicules est conçu pour permettre l’usage de TrAD sur autoroute aussi bien qu’en ville. Pour éviter l’encombrement des canaux de communication, un mécanisme illustratif de contrôle de la congestion reposant sur une approche distribuée est utilisé. Trois protocoles IVC de l’état de l’art ont été comparés à TrAD dans des scénarios réalistes de simulation, basés sur différentes villes réelles, différents trajets et densités véhiculaires. Les performances de TrAD surpassent celles des protocoles de référence en termes de taux de délivrance des paquets (PDR : Packet Delivery Ratio), nombre de transmissions et latence. De plus, nous montrons que TrAD est tolérant, dans une certaine mesure, aux erreurs sur les données GPS. Pour s’assurer de la qualité des simulations, nous avons étudié le modèle de déplacement employé dans le simulateur de trafic, puis couplé ce dernier au simulateur de réseau, afin que les deux s’échangent des informations en temps-réel. Grâce à la compréhension acquise lors de l’analyse du modèle de déplacement, nous avons pu développer un simulateur de conduite de tramway pour la T2C (Transports en Commun de l’agglomération Clermontoise). Des tests menés sur le matériel roulant nous ont permis d’élaborer des modèles de déplacement fidèles correspondants aux diverses situations rencontrées par le tramway. L’affichage de la simulation est assuré par un flux vidéo ajusté plutôt que des images de synthèse, ce qui permet de limiter le coût de développement tout en garantissant un certain réalisme dans l’affichage. Ce projet est soutenu par la T2C pour une durée de deux ans
In the last two decades, Vehicular Ad hoc Network (VANETs) were developed significantly by both academic institute and industries association, since VANETs originate from traffic safety and are also an important application of Internet of Things / Web of Things (IoT/WoT) for Intelligent Transportation System (ITS), Intelligent Vehicles and Smart Cities. As an essential component of VANETs, Inter-Vehicle Communication (IVC) protocols face many critical challenges, in particular, because they relate to various specific applications. In this thesis, after elaborating on related knowledge of VANETs and state-of-the-art of IVC protocols, we propose a data dissemination protocol for vehicular networking, named TrAD, to disseminate efficiently warning messages from a source to vehicles in a range of interest (ROI). TrAD considers the status of road traffic and network traffic to adapt locally the strategy and the parameters of transmissions in order to optimize the global performance of IVC application. Moreover, a local vehicular cluster classification algorithm is designed to support TrAD to be performed in both highway and urban scenarios. In addition, an illustrative congestion control mechanism is used to avoid channel congestion using a distributed approach. Three state-of-the-art IVC protocols have been compared with TrAD by means of realistic simulations. The performance of all those protocols is evaluated quantitatively in various scenarios by taking into account different real road maps, trafic routes and vehicular densities. Compared with the reference protocols, TrAD gains an outstanding overall performance in terms of packet delivery ratio, number of transmissions and delay. Furthermore, TrAD also can tolerate a reasonable degree of GPS drift while achieving efficient data dissemination. In order to ensure the quality of simulations, we deeply investigated the mobility model of road traffic simulator, and then performed the bidirectionally coupled simulation in which the network simulator and the road trafic simulator can exchange information in real-time. Upon understanding of the mobility model, we obtained a chance to develop a low-cost tram simulator for the local public transportation provider, the T2C (Transports en Commun de l’agglomération Clermontoise). We attempt to design accurate mobility models from different scenarios for the specific type of tram used by T2C. Real world trials are carried out to explore the key parameters required by theoretical deduction for our mobility model. Moreover, the display GUI relies on a video stream, rather than 3D graphics, which can reduce the cost while guaranteeing the quality of service. This project was supported for two years by T2C

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Mnassri, Radhia. "Réseaux de Petri Lots Triangulaires pour la modélisation mésoscopique et l'étude de la congestion dans le trafic routier." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4376.

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L'usage excessif des routes peut entraîner de nombreux inconvénients dont la pollution, les accidents et la congestion. Une solution accessible à court terme consiste à mettre en œuvre des systèmes de gestion de trafic. Dans ce cadre, nous proposons un formalisme, appelé Réseaux de Petri Lots Triangulaire, qui permet la modélisation et la simulation du trafic routier au niveau mésoscopique comme un système à événements discrets. Le RdPLots Triangulaire permet ainsi de décrire les caractéristiques globales du trafic routier: flux, densité et vitesse à travers la proposition d'une relation flux-densité triangulaire. Cette relation implique une modification de la dynamique des lots. Cette dynamique permet maintenant de représenter les deux états du trafic routier à savoir fluide et congestionné ainsi que les trois régimes dédiés au comportement libre, congestion et décongestion. Le calcul des flux instantanés des transitions est à présent réalisé par une méthode basée sur la technique de programmation linéaire en ajoutant une contrainte qui prend en compte l'état et le régime des lots. Pour modéliser des stratégies de contrôle telles que la variation de la vitesse limite (VSL), nous avons intégré au RdPLots Triangulaire des événements contrôlés qui permettent le changement de la vitesse maximale d'une place lot et le flux maximal d'une transition continue ou lot. Tous ces apports théoriques sont implémentés dans un logiciel que nous avons appelé SimuleauTri, sous lequel nous avons étudié des portions d'autoroute à partir des données réelles. Les résultats de simulation sont proches des mesures effectuées sur le terrain, et montrent la pertinence de RdPLots Triangulaire
The excessive use of roads can cause many adverse effects including pollution, insecurity and congestion. The available short-term solution is the implementation of traffic management systems which optimize the flow and reduce congestion without needing additional infrastructures. In this context, we proposed a new formalism, called Triangular Batches Petri Nets (Triangular BPN), which combines modeling and simulation of traffic in mesoscopic level as a discrete event system. The Triangular BPN describing the overall characteristics of the road traffic such as flow, density, speed by representing a new triangular relation flow-density. This relation implies the modification of batches dynamic, which is now used to represent the two road traffic states : fluid and congested, as well as the three behaviors :free, congestion and decongestion. The calculation of the instantaneous firing flows is achieved by adding a constraint that takes into account the state and behavior of batches. A set of controlled events integrated to the Triangular BPN, that allow the variation of the maximum speed of batch place and the maximum flow of batch and continuous transition. These controlled events used to model the control strategies, such as variable speed limit (VSL). All these theoretical contributions implemented in a software that is called SimuleauTri and used to study a motorway portions from real data. The simulation results are close to the measurements on the ground and show the pertinence of Triangular BPN

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Coelho, Renato Schattan Pereira 1987. "Simulação de multidões e planejamento probabilístico para otimização dos tempos de semáforos." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275643.

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Orientadores: Siome Klein Goldenstein, Jacques Wainer
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação
Made available in DSpace on 2018-08-22T23:53:33Z (GMT). No. of bitstreams: 1 Coelho_RenatoSchattanPereira_M.pdf: 864445 bytes, checksum: 8f57902047a23925af4b81fa0d7f3188 (MD5) Previous issue date: 2013
Resumo: O trânsito é um problema cada vez maior nas cidades, consumindo recursos e agravando a poluição; em São Paulo perdem-se cerca de R$33 bilhões por ano por causa do trânsito. Neste trabalho de mestrado desenvolvemos um sistema que une as áreas de simulação de multidões e planejamento probabilístico para otimizar semáforos de tempo fixo. Essas duas áreas apresentam algoritmos que permitem soluções eficientes para os problemas, mas a sua aplicação ainda depende largamente da intervenção de especialistas no problema a ser estudado, seja descrevendo o problema de planejamento probabilístico, seja interpretando os dados devolvidos pelo simulador. Nosso sistema diminui essa dependência ao utilizar autômatos celulares para simular o tráfego e gerar informações que são então utilizadas para descrever o problema de planejamento probabilístico. Com isso podemos: (i) reduzir a necessidade de coleta de dados, que passam a ser gerados pelo simulador e (ii) produzir bons planos para o controle de semáforos de tempo fixo sem que seja necessária a intervenção de especialistas para a análise dos dados. Nos dois testes realizados a solução proposta pelo sistema diminuiu o tempo médio de percurso em 18:51% e 13:51%, respectivamente
Abstract: Traffic is an ever increasing problem, draining resources and aggravating pollution. In Sao Paulo, for instance, financial losses caused by traffic represent a sum of about R$33 billions a year. In this work we've developed a system that puts together the areas of Crowd Simulation and Probabilistic Planning to optimize fixed time traffic lights. Although both areas present good algorithms their use is limited by their reliance on specialists, whether to describe the probabilistic planning problem or to analyze the data produced by the simulations. Our approach contributes to minimize this dependence by using cellular automata simulations to generate the data that is used to describe the probabilistic planning problem. This allows us to: (i) reduce the amount of data collection, since the data is now generated by the simulator and (ii) produce good policies for fixed time traffic light control without the intervention of specialists to analyze the data. In the two tests performed the solution proposed by the system was able to reduce travel times by 18:51% and 13:51%, respectively
Mestrado
Ciência da Computação
Mestre em Ciência da Computação

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Granlöf, Henrik, and Björn Hansson. "Användning av trafiksignaler och förändrad utformning för att öka kapaciteten i cirkulationsplatser." Thesis, Linköping University, Department of Science and Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6225.

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Sammanfattning

Det har byggts många rondeller under senare delen av 1990-talet och början av 2000-talet för att skapa bättre trafikmiljöer, minska fördröjningar och öka flexibiliteten i korsningar. I cirkulationsplatser med hög belastning och ojämna flöden kan det dock uppkomma en del problem. Ett av dessa problem kan vara att stora överordnade flöden genom rondeller blockerar trafik från mindre infarter så att långa köer bildas. I denna rapport analyseras olika åtgärder, som införandet av trafiksignaler och förändrad utformning, för att se om förbättringar är möjliga. Examensarbetet har lett till en god inventering och ökad kunskap kring problematiken kring cirkulationsplatser.

Presentationen av examensarbetet är uppdelat i fem delar:

Litteraturstudien gav intressant kunskap om möjligheterna med att använda trafiksignaler och fysiska förändringar för att öka kapaciteten i en hårt belastad cirkulationsplats. Litteraturen som använts hämtades främst från studier gjorda utomlands. Där fanns överbelastade cirkulationsplatser i hårt trafikerade områden där långa köer ofta uppstod vid rusningstrafik. Vidare studerades möjligheterna med att använda mikrosimulering för att modellera och utvärdera en trafiksignalreglerad cirkulationsplats.

En enkät genomfördes via mail och telefonsamtal. Genom mail bildades snabbt en uppfattning om vilka problem som existerar och därefter kontaktades de personer som besitter intressanta kunskaper och information via telefon. Enkätsvaren ledde till att en rad intressanta cirkulationsplatser lokaliserades varav två i Lund valdes ut som testobjekt.

Den trafikmätning som genomfördes gav god kunskap om den trafik i området som sedan simulerades. Trots att mätningen endast genomfördes under en dag så gav den all nödvändig indata för uppbyggandet av simuleringsmodellen.

I simuleringsdelen bearbetades först all indata för att kunna användas i mikrosimuleringsprogramvaran AIMSUN. Sedan byggdes en modell upp över cirkulationsplatserna som kalibrerades för att överrensstämma så bra som möjligt med verkligheten.

I experimentdelen prövades de kapacitetshöjande åtgärder som valts att undersökas för att förbättra rondellen och det visade en del intressanta resultat.

Det visade sig att trafiksignaler i detta fall inte ger någon förbättring av cirkulationsplatsens funktion. Däremot blev det stora förbättringar vid förändring av den fysiska utformningen. Det behövdes inte omfattande ingrepp för att öka effektiviteten utan en förändring av körfältsmålningen gav stora förbättringar. Slutsatserna är att man i Lund bör prova möjligheterna att förändra målningen, bygga separat högerkörfält eller utöka antalet cirkulerande körfält i cirklationsplatsen. Trafiksignaler i cirkulationsplatser bör dock undersökas noggrannare i Sverige, särskilt där trafikflödena är mycket höga, då denna regleringsform har givit bra resultat utomlands.

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Souza, Leandro Pugliesi de. "Um modelo para análise da compatibilidade de tráfego entre um caminhão ou uma combinação de veículos de carga e um trecho de rodovia." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-14102009-161939/.

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Esta pesquisa avalia a aplicabilidade de modelos matemáticos para analisar a compatibilidade de tráfego de caminhões e combinações de veículos de carga com trechos de rodovias. Os modelos avaliados permitiram a elaboração de um simulador de tráfego de veículos rodoviários de carga em trechos de rodovias, permitindo determinar o perfil de velocidades com base nas características mecânicas do veículo e o perfil da rodovia. O método permite ainda obter os valores de aceleração, potência utilizada, e consumo de combustível. Os resultados obtidos mostraram-se consistentes com observações de campo e recomendações de manuais de projeto de rodovias. Outros fatores associados à compatibilidade entre veículos e rodovias, como capacidade de frenagem motora, capacidade de frenagem de emergência, requisitos de sobrelargura, estabilidade veicular, influência do comportamento do condutor sobre as simulações, consumo de combustíveis e emissões de poluentes são discutidos. Conclui-se que o simulador tem utilidade tanto como ferramenta de análise da compatibilidade de tráfego de veículos de carga em trechos de rodovias, como para identificar deficiências de projeto geométrico de rodovias para autorizar o tráfego de determinadas configurações veiculares.
This research evaluates the applicability of mathematical models to analyze the traffic compatibility of trucks or cargo combination vehicles with road segments. The evaluated models led to a cargo vehicle locomotion simulator along a road segment, that calculates the speed profile of the vehicle as a function of its mechanical characteristics and the road profile. The method also calculates values of acceleration, used power, and fuel consumption. The results obtained are consistent with field observations and recommendations of road design manuals. Others factors associated with the traffic compatibility of cargo vehicles with geometric characteristics of a road segment like engine braking capability, emergency braking capability, overwidht requirements, vehicle stability, conductor influence, fuel consumption, and emissions rates are also discussed. The conclusion is that the simulator can be used as a tool for traffic compatibility analysis of cargo vehicles with road sections or to identify road design deficiencies to certify traffic of certain vehicle configurations.

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Chevrolet, Dominique. "Deux études de transport urbain : ordonnancement des phases d'un carrefour, modèles désagrégés de déplacements dans l'agglomération grenobloise." Phd thesis, Grenoble 1, 1986. http://tel.archives-ouvertes.fr/tel-00321160.

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La première partie de la thèse est consacrée au problème de la gestion des feux tricolore d'un carrefour, et la deuxième partie s'inscrit dans le cadre plus général de la modélisation des déplacements urbains

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Tapani, Andreas. "Traffic Simulation Modelling of Rural Roads and Driver Assistance Systems." Doctoral thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-12428.

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Microscopic traffic simulation has proven to be a useful tool for analysis of varioustraffic systems. This thesis consider microscopic traffic simulation of rural roads andthe use of traffic simulation for evaluation of driver assistance systems. A traffic simulation modelling framework for rural roads, the Rural Traffic Simulator(RuTSim), is developed. RuTSim is designed for simulation of traffic on singlecarriageway two-lane rural roads and on rural roads with separated oncoming trafficlanes. The simulated traffic may be interrupted by vehicles entering and leaving themodelled road at intersections or roundabouts. The RuTSim model is applied for analysis of rural road design alternatives.Quality-of-service effects of three alternatives for oncoming lane separation of anexisting Swedish two-lane road are analysed. In another model application, RuTSimis used to simulate traffic on a Dutch two-lane rural road. This application illustratesthat the high level of model detail of traffic micro-simulation may call for use of differentmodelling assumptions regarding driver behaviour for different applications,e. g. for simulation of traffic in different cultural regions. The use of traffic simulation for studies of driver assistance systems facilitateimpact analyses already at early stages of the system development. New and additionalrequirements are however then placed on the traffic simulation model. It isnecessary to model both the system functionality of the considered driver assistancesystem and the driver behaviour in system equipped vehicles. Such requirements canbe analysed using RuTSim. In this thesis, requirements on a traffic simulation model to be used for analysisof road safety effects of driver assistance systems are formulated and investigatedusing RuTSim. RuTSim is also applied for analyses of centre line rumble stripson two-lane roads, of an overtaking assistant and of adaptive cruise control. Thesestudies establish that the assumptions made regarding driver behaviour are crucialfor traffic simulation based analyses of driver assistance systems.

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Oner, Erdinc. "A SIMULATION APPROACH TO MODELING TRAFFIC IN CONSTRUCTION ZONES." Ohio University / OhioLINK, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1108146637.

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Abayneh, Alembo Zinash. "User delay costs and uncertainty in the traffic forecast for road projects." Thesis, KTH, Väg- och banteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149465.

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There are experimental based software packages as well as traffic simulation models that are used for analyzing life cycle cost of road projects. Among those our study was focused on currently available models to analyze the road user delay costs and to identify factors affecting road user delay costs. Sensitivity analyses were performed to identify the important factors that influence the user delay cost. Finally, prediction of future traffic demand as well as user delay cost, using the binomial lattice model, were presented to include the uncertainty of future traffic and user delay costs. The results of this study could help the highway designers with evaluating the future traffic.

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Sharma, Siddharth. "Development of a large-scale traffic simulation model for hurricane evacuation a case study of Virginia's Hampton Roads region /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6735.

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Thesis (M.S.)--University of Missouri-Columbia, 2008.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 22, 2008) Includes bibliographical references.

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Mariotte, Guilhem. "Dynamic Modeling of Large-Scale Urban Transportation Systems." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSET010/document.

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La congestion en milieu urbain est un enjeu majeur que ce soit d’un point vue économique, social ou environnemental. À court et moyen terme, l’utilisation de la simulation dynamique du trafic routier peut permettre d’analyser et de guider des politiques d’optimisation des infrastructures existantes. Aujourd’hui, du fait de la complexité des systèmes de transport, les outils de modélisation classiques sont limités à des échelles géographiques peu étendues (de l’ordre du quartier). À grande échelle, le temps de calcul devient rapidement un facteur limitant tout comme le calibrage et la scénarisation. Néanmoins les dernières décennies ont vu l’apparition d’une nouvelle génération de modèles bien adaptés aux métropoles urbaines. Ceux-ci sont basés sur une relation phénoménologique entre la production de déplacements et le nombre de véhicules dans une zone spatiale d’un réseau routier, appelée Diagramme Fondamental de Zone (Macroscopic Fundamental Diagram, MFD). Cette relation, validée empiriquement sur de nombreuses villes, a permis d’étudier différentes méthodes de contrôle du trafic pour une ville entière, mais a été peu utilisée à des fins de prévision de la congestion. L’objectif de cette thèse est de proposer un premier outil opérationnel de simulation et d’analyse des grands réseaux de métropoles, en utilisant et développant les modèles de trafic basés sur la relation MFD. Cet outil doit posséder un cadre théorique cohérent qui puisse convenir à des applications telles que la prévision d’états de trafic, le développement de nouvelles politiques de contrôle, l’estimation de pollutions liées au trafic, etc. Les contributions de la thèse portent sur deux aspects. Le premier est l’analyse des propriétés mathématiques et physiques des modèles existants, en incluant une formalisation complète de la gestion de plusieurs longueurs de parcours au sein d’une même zone urbaine. En particulier, cette formalisation traite de la distinction des trajets internes à la zone et des problèmes de flux convergents et divergents pour les trajets traversant la zone lorsque la congestion se propage d’une zone à l’autre. Le deuxième aspect est la proposition d’un nouveau modèle basé sur la distance individuelle parcourue à l’intérieur d’une zone urbaine (trip-based). Cette approche permet d’individualiser les usagers (auparavant représentés sous forme de flux continus) et donc de définir plus finement leurs caractéristiques, en vue de coupler leurs déplacements à des modèles d’affectations sur différentes routes. Enfin, des exemples d’application illustrant diverses collaborations sont donnés en dernière partie de la thèse. La simulation du trafic sur l’aire urbaine du Grand Lyon (France) y est présentée, ainsi que de nouveaux modules de modélisation de la recherche de parking ou de contrôle périphérique. Cette thèse est partie intégrante d’un projet européen ERC intitulé MAGnUM : Approche multi-échelle et multimodale de la modélisation du trafic pour une gestion durable de la mobilité urbaine
Congestion in urban areas has become a major issue in terms of economic, social or environmental impact. For short or mid term, using dynamic road traffic simulation can help analyzing and providing guidelines to optimization policies of existing infrastructures. Today, because of the complexity of transport systems, classical modeling tools are limited to small geographical areas (of a district size). Computational time, together with simulation calibration, are notably very constraining at large scales. However, a new generation of models designed for metropolitan areas has arisen over the past decades. These models are based on a phenomenological relationship between travel production and the number of vehicles in a given spatial area of a road network, known as the Macroscopic Fundamental Diagram (MFD). This relationship, supported by empirical evidences from several cities around the world, has allowed the study of different traffic control schemes at a whole city scale, but was rarely used for traffic state forecasting. The aim of this PhD is to propose an efficient modeling tool, based upon the concept of MFD, to simulate and analyze traffic states in large metropolitan areas. The theoretical framework of this tool must be consistent and applicable for traffic state forecasting, development of new control policies, traffic emission estimation, etc. There are two major contributions in this PhD. The first one is analyzing the mathematical and physical properties of existing models, and formalizing the dynamics of several trip lengths inside the same urban zone. In particular, this formalization distinguishes between internal trips and trips crossing the zone. Flow merging and diverging issues are also addressed when congestion propagates from one zone to another. The second contribution is proposing a new trip-based model based on individual traveled distance. This approach allows to treat users independently (previously represented with continuous flows), and thus to define their characteristics more precisely to couple their trips with assignment models on different paths. Finally, examples of application from various collaborations are given in the last part of this thesis. It includes a simulation study of the Grand Lyon urban area (France), as well as new modules to simulate search-for-parking or perimeter control. This PhD is part of a European ERC project entitled MAGnUM: Multiscale and Multimodal Traffic Modeling Approach for Sustainable Management of Urban Mobility

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Strömgren, Per. "Modelling of Traffic Performance for Swedish Roads and Motorways." Doctoral thesis, KTH, Transportplanering, ekonomi och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-185930.

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This thesis consists of five scientific articles oriented towards capacity. Managing capacity constraints with associated delays is a big issue at new design as well as at trimming existing traffic facilities. In larger Swedish cities these challenges have become more and more important as a result of growing traffic demand due to rapid population increase.Models for estimating capacity and delay are available, but not many are calibrated for Swedish conditions due to the high effort required. This thesis documents development and calibration of new models for motorway links, entry and exit lanes and weaving areas and an developed space-time model with the ability to calculate queue length, delay, etc.The first article is focused on identifying weaknesses in the former Swedish capacity method for motorways, and development of new models overcoming these shortcomings. The development includes new models for jam density at queue, capacity in weaving areas and fundamental flow-density relationships for 15 different highway types for inclusion in the new Swedish capacity manual.The second article describes the development of a Swedish motorway space-time model to estimate travel times and queues in oversaturated conditions based on the American FREEVAL model in Highway Capacity Manual 2010 (HCM 2010). Calibration and validation of the model has been performed with data from the Motorway Control System (MCS) in Stockholm. A good correspondence was obtained for most cases, but further calibration and validation efforts are required for entry and exit lanes.The third article describes further development of the intersection model in the Swedish microscopic model “Rural Traffic Simulator (RuTSim). This is a continuation of the work documented in the author’s licentiate thesis published in 2002. The development focused on simulation of intersections using a new concept on lane use not included in the old RuTSim model. The model describes Swedish rural intersections with flared approaches providing a non-discreet lane use due to vehicle types in queue. New data for calibration and validation data was also generated. The validation results showed good correspondence between simulated and empirical delay results. The new intersection model is now implemented in RuTSim, providing new tools for estimation of capacity, delay and queue length already included in Swedish guidelines and capacity manuals/software (Capcal).The fourth article describes the development of a new capacity model for roadwork zones. Focus is on the resulting capacity of one lane due to several reduction factors. These factors include impacts of closed road shoulders, reduction of number of lanes, diversion of traffic to the opposite carriageway, commuting traffic, length of work zone, lane width and type of road work. The first two correction factors were successfully validated in a full-scale test on the E6 motorway in Gothenburg.The fifth article describes development and implementation of a new harmonization algorithm for MCS systems on motorways designed to increase bottleneck capacity and throughput. Two different models were developed, one of which was implemented in the existing MCS system on E4 Södertäljevägen south of Stockholm. Full-scale trials were carried out with a model based on trigger levels in terms of flow. The second model based on the difference in the variance of speed during two following time periods was tested offline also with very good results.

QC 20160429

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Gioria, Gustavo dos Santos. "Influência da utilização do ABS na segurança veicular baseada na eficiência de frenagem e na probabilidade de travamento de roda." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18149/tde-22102009-105940/.

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O ABS (Antilock Braking System) é um sistema suplementar ao sistema de freio de serviço normal, que impede o travamento da roda em qualquer situação de frenagem, principalmente em frenagens de emergência, e com isto garante estabilidade e dirigibilidade ao veículo e reduz, na grande maioria de situações, a distância de parada em relação ao sistema de freio normal. Por sua vez, o travamento de roda na frenagem tem uma forte relação com acidentes de trânsito. Esta dissertação apresenta uma avaliação da eficiência do ABS na redução de acidentes de trânsito nas condições de uso cotidianas do veículo, baseando-se em uma característica da dinâmica do veículo: a eficiência de frenagem. Usualmente, esta avaliação da eficácia do ABS na prevenção de acidentes é feita através de estatísticas de dados de acidentes e de registros de veículos. O travamento da roda ocorre quando a demanda de aderência de veículo, que está diretamente relacionada com a desaceleração desejada, supera a aderência disponibilizada pelo conjunto pneu pavimento. Portanto através de curvas de probabilidade de disponibilidade de aderência, curvas de probabilidade de demanda de aderência e estatísticas sobre o uso do veículo, consegue-se estimar a probabilidade da ocorrência do travamento de roda. Este trabalho apresenta estimativas de acionamentos do freio para que ocorra um travamento, de distância percorrida para que ocorra um travamento e tempo decorrido para que ocorra um travamento. As estimativas são feitas para pistas de concreto seco e concreto molhado. Para esclarecer o funcionamento do sistema, simulou-se o sistema ABS em Matlab/Simulink. Para isto, desenvolveu-se um controlador de estados finitos, o qual foi implementado em um modelo de veículo completo. A simulação realizada foi uma frenagem em linha reta até a parada completa do veículo em uma pista homogênea de alta aderência. Neste estudo verificou-se que o ABS tem grande potencial para reduzir acidentes de trânsito, tanto em pista molhada quanto em pista seca. O ABS apresenta um ganho na segurança veicular mesmo em relação a um sistema de freio perfeitamente balanceado. Deve-se ressalvar que este resultado pode ser alterado pelo fator motorista, alteração esta causada pelo desconhecimento do funcionamento e utilização do sistema ou mesmo mau uso.
The ABS (Antilock Braking System) is a supplementary system to the regular service brake system, which prevents the wheel lock in any braking situation, mainly in emergency braking maneuvers, and it will guarantee stability and steerability of the vehicle and reduces, in most of the situations, the stopping distance in relation to the regular brake system. By the way, the wheel lock when braking has a strong relationship with traffic accidents. This thesis presents an assessment of the effciency of the ABS in the reduction of traffic accidents in daily conditions of use of the vehicle, based on a dynamic feature of the vehicle: the braking efficiency. Usually, this evaluation of the effectiveness of the ABS in the prevention of accidents is done through database statistics of accidents and records of vehicles. The wheel lock occurs when the friction demand of the vehicle, which is directly related to the desired deceleration, is larger than the friction provided by the interaction between the tire and the road surface. So through probability curves of availability of friction, probability curves of friction demand and statistics on the use of the vehicle, it is possible to estimate the probability of occurrence of wheel lock-ups. This study presents estimations of brake applications to cause a lock-up, estimations of distance travelled to cause a lock-up and estimations of time so that a wheel locks. The estimations are made for dry and wet concrete roads. To clarify the operation of the system, it was simulated the ABS system in Matlab/Simulink. In order to do this, it was developed a finite state controller, which was implemented in a full vehicle model. The simulation carried out was a straight line brake until the complete stop of the vehicle in a homogeneous high friction road. This study found out that the ABS has a great potential to reduce traffic accidents, both on wet road and on dry road. The ABS presents a gain in vehicles safety even in relation to a perfectly balanced brake system. It should be noted that this result can be affected by the driver factor, this change is caused by ignorance of the operation and use of the system or even misuse.

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Zajdák, Jiří. "Simulace provozu na silnicích a dálnicích." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2011. http://www.nusl.cz/ntk/nusl-236936.

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This thesis deals with a simulation of traffic on roads and highways. The thesis analyzes important concepts of road traffic law and their relation to simulation system. Further are here described problems of design and creation of traffic network which simulator uses. Work explains principles of models of behaviour of traffic participants which are extensible by force of plug-ins. The thesis also valorizes how many details is advisable to model the reality in particular parts of simulating system.

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Pajjuri, Srinivas Reddy. "Computer model to simulate truck accidents on exit ramps." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-08182009-040509/.

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Porč, Jiří. "Autoškola - pravidla silničního provozu." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-237142.

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This diploma thesis focuses on a traffic simulator design. The matter of simulation methods is described here as well as a project of a town model, road system and its usage in an implementation in a traffic simulator. The work further explains the principles and techniques for creation of the town model in an editor and it analyzes traffic rules that are necessary for the creation of the simulator of this type. The created simulator uses various engines for its functioning. It would not be possible to continue in further work without their proper adjustment. That is why the installation of the used engines is described in the thesis. Principles of 3D model and texture usage are also explained.

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Modak, Anagha Gurunath. "Road Accident Reconstruction and Simulation With and Without EDR Data." 2011. http://hdl.handle.net/1805/2629.

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Indiana University-Purdue University Indianapolis (IUPUI)
Road accident reconstruction and simulation investigates the accident causes, suggests improvements in vehicle design and investigates failures in vehicle control and safety systems such as the anti-lock brake system (ABS) and air-bag deployment. This thesis focuses on analysis of crash data from vehicles not equipped with collision warning systems. Vehicle parameters before and during an accident can be recorded using an Event Data Recorder (EDR) which helps in reconstructing an accident. This tool, installed in the vehicle, records different crash parameters like vehicle speed, lateral and longitudinal acceleration, seat-belt status, and air-bag deployment over a period that spens the accident. This thesis focuses on accident reconstruction with and without EDR data. A simulation software tool called HVE is used to visually recreate the reconstructed accidents. HVE is a platform to execute different accident simulation methods which are used for specific types of simulations. Two such simulation methods, EDSMAC4 and EDHIS, are discussed in this thesis. The former is an important method for vehicle-to-vehicle collisions and the latter is used for analysis of human behavior involved in the accident. Three real-life accidents were chosen for reconstruction and simulation. They were Bus and Car accident, Three Vehicle accident and Intersection accident. These particular accidents were chosen to represent a diverse selection of accidents based on the following parameters: the locations of the accidents, the vehicles involved in each accident, and the data available. A qualitative analysis of vehicle occupant's behavior is also presented for one of the three accidents. The thesis discusses in detail the reconstruction of these three accidents. Throughout these simulations, the thesis illustrates the advantages and limitations of the EDR and HVE simulation software for accident reconstruction and simulation.

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Wang, Chao-Sheng, and 王朝盛. "Building a Realistic Vehicular Network Simulation: the Integration of the Road Traffic Simulator and the Network Simulator." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/62168954918419053384.

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碩士
國立臺灣大學
資訊工程學研究所
100
Recently, the applications of Vehicular Ad-hoc Networks (VANETs) in many existing researches have mainly been related to information distribution and traffic safety. However, in the researches that aim at designing the network protocols and systems for VANETs, performance evaluation usually does not utilize realistic traffic flow data; therefore, the derived design might actually not perform well in the real world. In VANETs, the nodes, i.e., the vehicles, have many unique features: they have high mobility, and the topology often changes rapidly; the movements of the vehicles need to follow the general traffic rules and obey the traffic signs. As a result, how realistic the traffic mobility model is can have significant impact on whether the simulations of VANETs are sufficiently realistic. The main goal of this thesis is to build an integrated simulation framework, which can be utilized to study the Inter-Vehicle Communications (IVC) in VANETs. The framework integrates a traffic mobility simulator and a network simulator; in the framework, the traffic mobility simulator generates realistic traffic mobility information, such as the location and the velocity of the vehicles, and feeds it to the network simulator in real-time. The network simulator would then be able to model the communications between moving vehicles in a more realistic way. This enables the researchers to study and design the network protocols, systems, and applications in VANETs in a setting closer to the reality – with realistic traffic flow information. In this research, we implement the integration of Simulations of Urban Mobility (SUMO) (as the traffic mobility simulator) and OPNET Modeler (as the network simulator) to realize this framework. In the second part of this thesis, we utilize the developed framework to investigate the feasibility of the networked camera application. In this application, cars with cameras can utilize the IVC to send the captured video to neighboring vehicles, whose drivers can then observe the video and react accordingly. This is especially useful when the view of the driver is blocked; the functionality is similar to the mirror installed at the side of the road, but could serve the purpose at almost any location. We simulate this application in 3 different scenarios with the developed framework: intersections with traffic signals, intersections without traffic signals in the urban area, and a highway scenario, and adjusted various parameters, such as vehicle density, link data rate, and video resolution, to compare the system performance in different settings. Performance metrics such as packet delivery ratio and end-to-end delay are measured and compared. The results show that the quality of service of the tested application is strongly affected by the vehicle density, which is determined by the neighboring road structure and the traffic light status. We also found that in most applicable scenarios, it is required to use a link data rate as high as 36 Mbps so that the video quality is acceptable for the driver.

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Dissertations / Theses on the topic 'Road traffic simulation'

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