Light Emitting Diode (LED) is used in traffic signals and highway illumination in the Texas Department of Transportation, Houston District (TxDOT). The thesis focuses on the cost of maintenance of the LED for signals on the highway system in the Houston District. This LED cost includes human and capital resources which are compared against the cost associated with the incandescent bulb used in traffic signals at a similar location in Houston. The analysis leads to actionable decisions to see if total migration of the LED is advisable or not, amidst budgetary constraints and the benefits thereof. / text

Traffic State Estimation (TSE) is a vital component in traffic control which requires an accurate viewof the current traffic situation. Since there is no full sensor coverage and the collected measurementsare inflicted with random noise, statistical estimation techniques are necessary to accomplish this.Common methods, which have been used in highway applications for several decades, are state-spacemodels in the form of Kalman Filters and Particle Filters. These methods are forms of BayesianFilters, and rely on transition models to describe the system dynamics, and observation models torelate collected measurements to the current state. Reliable estimation of traffic in urban environmentshas been considered more difficult than in highways owing to the increased complexity.This MsC thesis build upon previous research studying the use of non-parametric Gaussian Processtransition and measurement models in an extended Kalman Filter to achieve short-term TSE. To dothis, models requiring different feature sets are developed and analysed, as well as a hybrid approchcombining non-parametric and parametric models through an analytical mean function based on vehicleconservation law. The data used to train and test the models was collected in a simulated signalizedintersection constructed in SUMO.The presented results show that the proposed method has potential to performing short-term TSE inthis context. A strength in the proposed framework comes from the probabilistic nature of the GaussianProcesses, as it removes the need to manually calibrate the filter parameters of the Kalman Filter. Themean absolute error (MAE) lies between one and five vehicles for estimation of a one hour long dataseries with varying traffic demand. More importantly, the method has desirable characteristics andcaptures short-term fluctuations as well as larger scale demand changes better than a previously proposedmodel using the same underlying framework. In the cases with poorer performance, the methodprovided estimates unrelated to the system dynamics as well as large error bounds. While the causefor this was not determined, several hypotheses are presented and analysed. These results are takento imply that the combination of BF and GP models has potential for short-term TSE in a signalizedintersection, but that more work is necessary to provide reliable algorithms with known bounds. In particular,the relative ease of augmenting an available analytical model, built on conventional knowledgein traffic modelling, with a non-parametric GP is highlighted.

Enabling vehicles to preempt the normal operation of traffic signals has the potential to improve the safety and efficiency of both the requesting vehicle and all of the other vehicles. Little is known about which strategy is the most effective to exit from preemption control and transition back to the traffic signals normal timing plan. Common among these traffic signal transition strategies is the method of either increasing or decreasing the cycle length of the signal timing plan, as the process followed to return to the coordination point of the effected signal timing plan, to coordinate its operation with adjacent traffic signals. This research evaluates commonly available transition strategies: best way, long, short, and hold strategies. The major contribution of this research is enhancing the methodology to evaluate the impacts of using these alternative transition strategies. Part of this methodology consists of the "software-in-the-loop" simulation tool which replicates the stochastic characteristics of traffic flow under different traffic volume levels. This tool combines the software from a traffic signal controller (Gardner NextPhase Suitcase Tester, version 1.4B) with a microscopic traffic simulation model (CORSIM, TSIS 5.2 beta version). The research concludes that a statistically significant interaction exists between traffic volume levels and traffic signal transition strategies. This interaction eliminates the ability to determine the isolated effects of either the transition strategies on average travel delay and average travel time, or the effects of changes in traffic volume levels on average travel delay and average travel time. Conclusions, however, could be drawn on the performance of different transition strategies for specific traffic volume levels. As a result, selecting the most effective transition strategy needs to be based on the traffic volume levels and conditions specific to each traffic signal or series of coordinated traffic signals. The research also concludes that for the base traffic volume and a 40% increase in traffic volume, the most effective transition strategies are the best way, long or hold alternatives. The best way was the most effective transition strategy for a 20% increase in traffic volume. The least effective strategy is the short transition strategy for both the base and 40% increase in traffic volume, and the long and short for a 20% increase in traffic volume. Further research needs to be conducted to assess the performance of different transition strategies in returning to coordinated operation under higher levels of traffic volume (e.g., approaching or exceeding congested flow regime), with varying cycle lengths, with different signal timing plans, and when different roadway geometric configurations (e.g., turn lanes, length of turn lanes, number of lanes, spacing between intersections) are present. / Ph. D.

Este trabalho contém os seguintes tópicos: fundamentos sobre a operação de semáforos e descrição de alguns modelos analíticos de avaliação do desempenho de semáforos isolados e coordenados; considerações sobre simulação do tráfego de veículos e comentários sobre alguns dos principais modelos de simulação desenvolvidos; descrição do simulador de tráfego INTEGRATION; análise dos valores obtidos com o INTEGRATION em alguns casos simples de cruzamentos com semáforos isolados e coordenados, através da comparação com os resultados fornecidos por outros modelos teóricos de avaliação do desempenho de semáforos; e emprego do simulador INTEGRATION na avaliação de algumas alternativas de operação de um trecho de via semaforizado da cidade de Manágua- Nicarágua. Os valores obtidos com o INTEGRATION nos casos simples de cruzamentos com semáforos isolados e coordenados mostram-se próximos dos fornecidos por outros modelos teóricos, bem como consistentes com o comportamento real da operação de veículos em semáforos isolados e coordenados. A análise da situação atual do trecho de via de Manágua analisado mostrou dois pontos importantes: primeiro, o trânsito no local se encontra totalmente congestionado nos horários de pico; segundo, alterações na programação dos semáforos não resolvem o problema, sendo necessário o aumento de uma faixa em cada sentido na via principal. Considerando o aumento das duas faixas, foram gerados seis cenários de operação, numa combinação envolvendo os seguintes aspectos: semáforos isolados ou coordenados, existência de conversão à esquerda ou não e coordenação na via principal num e no outro sentido. Todos esses cenários mais o cenário atual foram avaliados utilizando o simulador INTEGRATION. Os resultados apontam que os melhores cenários são aqueles em que é proibida a conversão à esquerda. Por circunstâncias particulares, a coordenação dos semáforos não apresentou os benefícios que normalmente apresenta. / The following topics are enclosed in this work: fundamentals about traffic signals operation and description of some analytical models of evaluation of isolated and co-ordinated traffic signals performance; considerations about the traffic of vehicles simulation and comments regarding some of the main developed simulation models; description of the traffic simulator INTEGRATION; analysis of the values obtained using INTEGRATION in some simple cases of intersections with isolated traffic signals and coordinated, through the comparison with the supplied results obtained in other theoretical evaluation models of the traffic signals performance; and INTEGRATION simulator application in the evaluation of some operation alternatives of a signalized stretch in the city of Managua-Nicaragua. The values obtained with the INTEGRATION in the simple cases of intersections with isolated and co-ordinated traffic signals are close to the supplied ones by theoretical models, as well as consistent with the real behavior of vehicles operation at isolated and co-ordinated traffic signals. The current situation analysis of the stretch of way of Managua indicated that: the local traffic is totally congested in the peak times; and the alterations in the traffic signals programing do not solve the problem; having the necessity of increasing and additional lane in the main lane. Considering the increase of these two lanes, six scenary of operation were generated, in a combination involving the following aspects: isolated and co-ordinated traffic signals, existence of conversion the left turn or not and co-ordinated traffic signals in the main way in one on the other direction. All these scenes and the current scene had been more evaluated using simulator INTEGRATION. The results point that the best scenes are those where it is forbidden the left turn. For particular circunstances, the co-ordinated traffic signals did not present benefits that normally present.

Este trabalho contém os seguintes tópicos: fundamentos sobre a operação de semáforos e descrição de alguns modelos analíticos de avaliação do desempenho de semáforos isolados e coordenados; considerações sobre simulação do tráfego de veículos e comentários sobre alguns dos principais modelos de simulação desenvolvidos; descrição do simulador de tráfego INTEGRATION; análise dos valores obtidos com o INTEGRATION em alguns casos simples de cruzamentos com semáforos isolados e coordenados, através da comparação com os resultados fornecidos por outros modelos teóricos de avaliação do desempenho de semáforos; e emprego do simulador INTEGRATION na avaliação de algumas alternativas de operação de um trecho de via semaforizado da cidade de Manágua- Nicarágua. Os valores obtidos com o INTEGRATION nos casos simples de cruzamentos com semáforos isolados e coordenados mostram-se próximos dos fornecidos por outros modelos teóricos, bem como consistentes com o comportamento real da operação de veículos em semáforos isolados e coordenados. A análise da situação atual do trecho de via de Manágua analisado mostrou dois pontos importantes: primeiro, o trânsito no local se encontra totalmente congestionado nos horários de pico; segundo, alterações na programação dos semáforos não resolvem o problema, sendo necessário o aumento de uma faixa em cada sentido na via principal. Considerando o aumento das duas faixas, foram gerados seis cenários de operação, numa combinação envolvendo os seguintes aspectos: semáforos isolados ou coordenados, existência de conversão à esquerda ou não e coordenação na via principal num e no outro sentido. Todos esses cenários mais o cenário atual foram avaliados utilizando o simulador INTEGRATION. Os resultados apontam que os melhores cenários são aqueles em que é proibida a conversão à esquerda. Por circunstâncias particulares, a coordenação dos semáforos não apresentou os benefícios que normalmente apresenta. / The following topics are enclosed in this work: fundamentals about traffic signals operation and description of some analytical models of evaluation of isolated and co-ordinated traffic signals performance; considerations about the traffic of vehicles simulation and comments regarding some of the main developed simulation models; description of the traffic simulator INTEGRATION; analysis of the values obtained using INTEGRATION in some simple cases of intersections with isolated traffic signals and coordinated, through the comparison with the supplied results obtained in other theoretical evaluation models of the traffic signals performance; and INTEGRATION simulator application in the evaluation of some operation alternatives of a signalized stretch in the city of Managua-Nicaragua. The values obtained with the INTEGRATION in the simple cases of intersections with isolated and co-ordinated traffic signals are close to the supplied ones by theoretical models, as well as consistent with the real behavior of vehicles operation at isolated and co-ordinated traffic signals. The current situation analysis of the stretch of way of Managua indicated that: the local traffic is totally congested in the peak times; and the alterations in the traffic signals programing do not solve the problem; having the necessity of increasing and additional lane in the main lane. Considering the increase of these two lanes, six scenary of operation were generated, in a combination involving the following aspects: isolated and co-ordinated traffic signals, existence of conversion the left turn or not and co-ordinated traffic signals in the main way in one on the other direction. All these scenes and the current scene had been more evaluated using simulator INTEGRATION. The results point that the best scenes are those where it is forbidden the left turn. For particular circunstances, the co-ordinated traffic signals did not present benefits that normally present.

This thesis is focused on analysis and evaluation of the trolley deceleration effect on his standing passengers. The first part focuses on theoretical knowledge in terms of legislative requirements for the operation of trolleybuses and transport standing passengers. This section also lists physical findings during deceleration and forces acting on the vehicle. The central part is divided into two measurements. The first measure is aimed at obtaining data (deceleration) and information (number of passengers, increased stability, and fall) of the normal operation of the standing passengers in interior trolley. The second measurement will be focused on driving performance demonstration tests with the interior trolley helpers in various traffic situations. The conclusion of this thesis will summarize the values and knowledge of both measurements. The evaluated data set will limit the slowdown in the trolley passengers where standing still maintains stability.

A discrete-time stochastic optimal control problem was recently proposed to address the GLOSA (Green Light Optimal Speed Advisory) problem in cases where the next signal switching time is decided in real-time and is therefore uncertain in advance. However, there was an assumption that the traffic signal is initially red and turns to green, which means that only half traffic light cycle was considered. In this work, the aforementioned problem is extended considering a full traffic light cycle, consisting of four phases: a certain green phase, during which the vehicle can freely pass; an uncertain green phase, in which there is a probability that the traffic light will extend its duration or turn to red at any time; a certain red phase during which the vehicle cannot pass; and an uncertain red phase, in which there is a probability that the red signal may be extended or turn to green at any time. It is demonstrated, based on preliminary results, that the proposed SDP (Stochastic Dynamic Programming) approach achieves better average performance, in terms of fuel consumption, compared to the IDM (Intelligent Driver Model), which emulates human-driving behavior.

Syftet med projektet var att ta fram en ny cykelbelysning för att höja cyklisters säkerhet och förenkla trafikregler samt utförandet av signalering. Genom en nulägesanalys av befintliga produkter, elektronikkomponenter och slutanvändarnas uttalanden kunde kundbehov tas fram. Därefter rangordnades kundbehoven och en funktionslista tillsammans med en produktspecifikation kunde verkställas. Med dem som grund utfördes en idégenerering med flera olika lösningskoncept där ett val gjordes baserat på en Kesselringmatris. Det vinnande konceptet var ett par pedaler med integrerad belysning. Genom en accelerometer fungerar pedalen som en bromslykta och med hjälp av en extern kontroll kan körriktningsvisare sättas igång som projiceras på marken. Elektriciteten som behövs till pedalernas belysning genereras när cyklisten roterar pedalaxeln via en generator. Som slutsats uppfylldes projektets mål men mer arbete behöver göras kring projektets avgränsningar för en färdig produkt. / The purpose of the project was to develop a new bicycle light in order to improve cyclists’ safety and to make it easier for them to follow traffic regulations. Using a status analysis of existing products, electronics and the end users statements the customer needs could be documented. Then the needs were ranked and a function list together with a product specification was produced. With them as a base the brainstorming could begin where multiple concept solutions were made and one of them chosen as a winner through a Kesselring matrix. The winning concept was a pair of pedals with integrated lighting. With the help of an accelerometer the pedal worked as a brake light and with an external control system turn signals could be turned on and were projected on the ground. The electricity needed for the pedals light system is generated when the user rotates the pedal axis with the help of a generator. As a conclusion all the project goals were fulfilled but more work needs to be done regarding the projects limitations for a complete production ready product.