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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Propuesta de mejora de niveles de servicio en la intersección vial entre la carretera Panamericana Sur km 37.5 y el puente Arica en la ciudad de Lima / Proposal to improve service levels at the road intersection between the Highway Panamericana Sur km 37.5 and the Arica Bridge in the city of Lima

Vertiz Zavaleta, Julio Cesar, Ramon Avalos, Victor Eduardo 16 January 2020 (has links)
La Carretera Panamericana Sur km. 37.5 y el Puente Arica, es una intersección vial tipo Diamante Convencional partido sin semáforos, ubicado en el distrito de Lurín y provincia de Lima. Esta intersección presenta congestionamiento vehicular ocasionando pérdida de horas hombre. Debido a esto, se determinó los niveles de servicio actuales, a través del software Synchro 8.0, mediante aforos vehiculares tomados en campo. Los niveles de servicio obtenidos fueron muy bajos y demoras elevadas. Como consecuencia se plantearon y modelaron con el software Synchro 8.0 diferentes propuestas para solucionar la congestión vehicular, tales como; Implementación de cruceros semafóricos con diferentes diseños, implementación de mini óvalos dentro de la intersección y en los extremos de la intersección, y un intercambio vial de tipo Diamante Divergente. La propuesta de solución se inicia con la comparación de resultados obtenidos de las alternativas para el escenario actual y proyectado a 5 y 10 años. En consecuencia, se obtuvieron dos propuestas que solucionan la congestión vehicular actual y proyectada a 5 años. La primera es la implementación de cruceros semafórico con un carril exclusivo para el giro libre a la derecha y la segunda es la implementación de un novedoso intercambio vial de tipo Diamante Divergente, mientras que las demás propuestas no son sostenibles en la proyección del tránsito futuro. Por otro lado, si bien es cierto que ambas propuestas mejoran y dan solución al problema planteado la segunda presenta mejores niveles de servicio y menores demoras en la proyección a 10 años. / The South Pan American Highway km. 37.5 and the Arica Bridge, is a Conventional Diamond-type road intersection without traffic lights, located in the district of Lurín and province of Lima. This intersection presents vehicular congestion causing loss of man-hours. Due to this, the current service levels were determined, through Synchro 8.0 software, through vehicle capacities taken in the field. The service levels obtained were very low and delays were high. As a consequence, different proposals were proposed and modeled with Synchro 8.0 software to solve vehicular congestion, such as; Implementation of traffic lights with different designs, implementation of mini ovals within the intersection and at the ends of the intersection, and a Divergent Diamond road interchange. The solution proposal begins with the comparison of results obtained from the alternatives for the current scenario and projected at 5 and 10 years. Consequently, two proposals were obtained that solve the current and projected vehicular congestion at 5 years. The first is the implementation of traffic light cruises with an exclusive lane for the free right turn and the second is the implementation of a new Divergent Diamond interchange, while the other proposals are not sustainable in the projection of future traffic. On the other hand, although it is true that both proposals improve and solve the problem posed, the second presents better levels of service and less delays in the 10-year projection. / Tesis
2

Simulation dynamique du trafic routier urbain et optimisation des contrôles

Hua, Lefong January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
3

OPTIMISATION DES PERFORMANCES DES MACHINES SYNCHRO-RELUCTANTES PAR RESEAUX DE PERMEANCES

Raminosoa, Tsaarafidy 05 October 2006 (has links) (PDF)
Du fait de sa robustesse et de son faible coût, la machine synchro-réluctante (MSR) constitue une alternative intéressante à la machine asynchrone. A pertes égales, une MSR bien optimisée offre un couple et par suite un rendement plus élevés. Ainsi, la MSR est très compétitive pour les applications à haute vitesse, à forte puissance ou à haute température. Cette thèse se propose d'optimiser les machines synchro-réluctantes à rotor massif et avec barrières de flux pour produire le maximum de couple avec un facteur de puissance le plus élevé possible. Pour cela, une modélisation originale utilisant des réseaux de perméances non linéaires a été mise au point pour les deux types de MSR. Les modèles proposés sont significativement plus rapides et aussi précis que les modèles par éléments finis. De plus, la réalisation d'un prototype à barrières de flux a permis de les valider expérimentalement.
4

Evaluation the level of service at a roundabout : A case study on Al-Ibrahimeya roundabout in Alexandria, Egypt

Iscan, Neval January 2019 (has links)
The capacity of today’s transportation network in Alexandria cannot handle the increasing number of vehicles. The root of traffic congestion in Alexandria is most likely as result of urban planning failure, an inadequate public transportation network, strong population growth, lack of enforcement of traffic laws, complex spatial street network and poor road quality.The aim with this thesis is to simulate various traffic scenarios for the purpose of studying, evaluating and improving the traffic conditions on the intersection Al-Ibrahimeya, however, for long-term efficiency and improvement in Al-Ibrahimeya, the traffic conditions in the entire system be improved.In this thesis, a model was built in the microscopic software VISSIM and macroscopic software SYNCHRO. The model is calibrated based on data collected from video recording. Two alternative solutions to overcome the congested traffic conditions were tested. Signalization has been the main alternative solution performed for intersection Al- Ibrahimeya.The simulation results showed some improvements in terms of delay and travel time. Roundabouts are usually suitable for under low to mid traffic conditions. When there is a heavy traffic flow, as in this case, roundabouts are not suitable and may cause problem in the network. Implementing signals led to some decrease in the entering and exiting flows because the total network became more controlled. However, an organized and well-functioning signalization program helped to reduce delay and travel time in most of routes.
5

Dimensionnement d'une machine synchro-réluctante à excitation homopolaire par réseaux de perméances / Dimensioning a homopolar synchronous reluctance machine by permeance networks

Belalahy, Christian 14 November 2008 (has links)
Les travaux présentés ici portent sur le dimensionnement et l’étude d’une machine à réluctance variable excitée par un courant continu homopolaire de type``Lyndell´´. De telle structure connaît un regain d’intérêt avec de nouvelles topologies pour des applications spécifiques. Dans le cas des travaux présentés, l’application visée est la conversion d’énergie éolienne avec un stockage inertiel. Cette machine a une bobine d’excitation qui est solidaire du stator et située entre les pôles saillants. Le rotor est massif et comporte deux paires de pôles dont les axes polaires peuvent être parallèles ou perpendiculaires. Le stator possède deux enroulements sur deux demi-stators de machine classique dont l’un est fixe et l’autre orientable manuellement suivant l’axe de rotation du rotor. Cette possibilité d’orientation permet à la machine d’être équipée de l’un ou l’autre des deux types de rotor. Le dimensionnement et l’étude de cette machine sont basés sur le modèle des réseaux de perméances. L’élaboration du modèle, par une subdivision de la structure étudiée en zones à induction homogène, est effectuée à partir de l’analyse des lignes de champ obtenues par la méthode des éléments finis bidimensionnels pour l’ensemble « dent - entrefer - encoche », et les autres parties de la machine (culasse, rotor) sont tridimensionnels. Ces éléments finis constituent également la référence pour valider le modèle développé et pour vérifier le niveau de saturation de la machine. Le modèle par réseaux de réluctance est ensuite utilisé pour dimensionner un prototype, à pôles parallèles ou en quadrature et pour en étudier les performances à vide et en charge. Enfin, le prototype réalisé est étudié pour les deux types de rotor. Les résultats expérimentaux, comparés aux calculs de simulation, montre des concordances très satisfaisantes / The work presented here is devoted to the dimensioning and the study of a switched reluctance machine excited by a homopolar D.C. current of Lyndell type. Such structure knows a renewed interest with new topologies for specific applications. In the case of work had presented, the application concerned for is the wind energy transformation with an inertial storage. The field coil of the machine placed in the stator and is located between the rotor salient poles. The rotor is massive and comprises two pairs of poles. These poles have parallel or perpendicular axes. The stator has two windings placed on two classical half-stators, one of which is fixed and the other is manually adjustable along the axis of rotation of the rotor. This orientation allows the machine to be equipped with one or the other of two types of rotor. The dimensioning and the study of this machine are based on the model of the reluctance network. The development of the model, by a subdivision of the studied structure into homogeneous induction zones, is made from the flux lines obtained by the two-dimensional finite element method for whole tooth-air-gap-slot, and the other parts of the machine (stator breech, rotor) are three-dimensional. The finite element methods also constitute the reference to validate the developed model and check the saturation level of the machine. The reluctance network model is then used for sizing a prototype with the parallel or perpendicular poles and for studying the performances in no load and with load machine. Finally, the realised prototype is studied for both types of rotor. The experimental results compared with the simulation show very satisfactory concordances
6

Effects of U-Turns on Capacity at Signalized Intersections And Simulation of U-Turning Movement by Synchro

Wang, Xiaodong 28 March 2008 (has links)
The primary objective of this study is to evaluate the operational effects of U-turn movement at signalized intersections. More specifically, the research objectives include the following parts: To identify the factors affecting the operational performance of U-turning vehicles. In this case, we are particularly interested in the U-turn speeds of U-turning vehicles. To evaluate the impacts of U-turns on capacity of signalized intersections, and To simulate U-turn movement at signalized intersections using Synchro and validate the simulation results. To achieve the research objectives, extensive field data collection work was conducted at sixteen selected sites at Tampa Bay area of Florida. The data collected in the field include: U-turning speed Left turning speed Turning radius Queue discharge time Control delay Hourly traffic volume, and Percentage of U- turning vehicles in left turn lane. Based on the collected field data, a linear regression model was developed to identify the factors affecting the turning speeds of U-turning vehicles at signalized intersections. The model shows the turning speed is significantly impacted by the turning radius and the speed of U-turning vehicles increases with the increase of turning radius. On the basis of field data field data collection, a regression model was developed to estimate the relationship between the average queue discharge time for each turning vehicle and the various percentages of U-turning vehicles in the left turn traffic stream. Adjustment factors for various percentages of U-turning vehicles were also developed by using the regression model. The adjustment factors developed in this study can be directly used to estimate the capacity reduction due to the presence of various percentages of U-turning vehicles at a signalized intersection. The developed adjustment factors were used to improve the simulation of U-turn movement at signalized intersection by using Synchro. The simulation model was calibrated and validated by field data. It was found that using the developed adjustment factors will greatly improve the accuracy of the simulation results for U-turn movement.
7

Optimisation des performances des machines synchro-réluctantes par réseaux de perméances / Performance Optization of Synchronous Reluctance Machine Using Reluctance Network

Raminosoa, Tsarafidy 05 October 2006 (has links)
Du fait de sa robustesse et de son faible coût, la machine synchro-réluctante (MSR) constitue une alternative intéressante à la machine asynchrone. A pertes égales, une MSR bien optimisée offre un couple et par suite un rendement plus élevés. Ainsi, la MSR est très compétitive pour les applications à haute vitesse, à forte puissance ou à haute température. Cette thèse se propose d’optimiser les machines synchro-réluctantes à rotor massif et avec barrières de flux pour produire le maximum de couple avec un facteur de puissance le plus élevé possible. Pour cela, une modélisation originale utilisant des réseaux de perméances non linéaires a été mise au point pour les deux types de MSR. Les modèles proposés sont significativement plus rapides et aussi précis que les modèles par éléments finis. De plus, la réalisation d’un prototype à barrières de flux a permis de les valider expérimentalement. / Because of its robustness and its low cost, the synchronous reluctance motor (SynRM) is an interesting alternative to the induction motor. At equal losses, a correctly optimized SynRM offers a higher torque and then a higher efficiency. Thus, the SynRM is very comptetitive for high speed, high power or high temperature applications. This thesis intends to optimize massive rotor and flux barrier rotor SynRM to produce the maximum torque with the highest possible power factor. For this purpose, an original non linear reluctance network modeling of synchronous reluctance motors with a massive or a flux barrier rotor was developed. The proposed models are significantly faster than the finite element ones and take accurately into account the saturation of all ferromagnetic parts of the motor. The construction of a flux barrier rotor prototype allowed an experimental validation of the modeling approach.
8

Metodologia para seleção de ferramentas computacionais para o ensino de engenharia de tráfego.

Martinez, Heloni Maura Martorano 30 October 2006 (has links)
Made available in DSpace on 2016-06-02T20:00:19Z (GMT). No. of bitstreams: 1 DissHMMM.pdf: 1405845 bytes, checksum: 222b42803d4101e33e5fe8fc1f8996ae (MD5) Previous issue date: 2006-10-30 / Computational tools - softwares become more and more useful in the scope of Engineering. Several authors have already confirmed its benefits for the engineering's students education. In the last years, the availability of specific softwares for Traffic Engineering have increased. Nowadays, the selection process to identify the more adjusted computational tool to each task is one of the major difficulties in its use. This paper presents a methodology for selecting computational tools - softwares to be used in teaching disciplines of Traffic Engineering. This methodology, named MESET - METHODOLOGY FOR SELECTING COMPUTATIONAL TOOLS FOR TEACHING TRAFFIC ENGINEERING, was based on United States Department of Transports method, (2004). Its original evaluation criteria and specific tasks were adapted for teaching use inside the Traffic Engineering s parameters from Brazilian reality. The component criteria and item were identified through research carried with Traffic Engineer s Brazilian universities teachers. After defining the adequate procedures and routines MESET was also demonstrated through the software Synchro/SimTraffic, demo version. Through the criteria adopted, MESET s application final results have indicated that the software Synchro is adjusted to teach the analysed item - the modeling of intersections traffic lights. / Ferramentas computacionais softwares vêm sendo cada vez mais utilizadas no âmbito da Engenharia. Para a formação dos futuros profissionais engenheiros, vários autores já confirmaram os benefícios de seu uso para o ensino. Na área de Engenharia de Tráfego, a disponibilidade de softwares específicos vem crescendo nos últimos anos e uma das dificuldades em sua utilização está no processo de seleção da ferramenta computacional mais adequada ao trabalho a ser realizado. Este estudo apresenta uma proposta de metodologia para seleção de ferramentas computacionais - softwares - para uso no ensino de disciplinas na área de Engenharia de Tráfego. Esta metodologia, denominada MESET - METODOLOGIA PARA SELEÇÃO DE FERRAMENTAS COMPUTACIONAIS PARA O ENSINO DE ENGENHARIA DE TRÁFEGO, foi adaptada a partir de um método do Departamento de Transportes dos Estados Unidos, do qual foram utilizados os critérios originais de avaliação para o processo de desenvolvimento e adaptação à tarefa especifica de uso no ensino, segundo parâmetros presentes na realidade brasileira. A identificação de critérios e itens componentes foi efetuada a partir de pesquisa realizada junto a professores de Engenharia de Tráfego de várias universidades brasileiras. Com a definição dos formulários adequados e rotina de procedimentos, a MESET é demonstrada para o software Synchro/SimTraffic, versão demo. Os resultados obtidos nesta aplicação da MESET indicaram que o Synchro se enquadra para o ensino do dimensionamento de semáforos para interseções e trechos, segundo os critérios adotados.
9

An Analysis of the Protected-Permitted Left Turn at Intersections with a Varying Number of Opposing Through Lanes

Navarro, Alexander 01 January 2014 (has links)
The Flashing Yellow Arrow Left Turn signal is quickly becoming prominent in Central Florida as a new method of handling left turns at traffic signals. While the concept of a protected-permitted left turn is not groundbreaking, the departure from the typical display of a five-section signal head is, for this type of operation. The signal head introduced is a four-section head with a flashing yellow arrow between the yellow and green arrows. With this signal head quickly becoming the standard, there is a need to re-evaluate the operational characteristics of the left turning vehicle and advance the knowledge of the significant parameters that may affect the ability for a driver to make a left turn at a signalized intersection. With previous research into the behavioral and operational characteristics of the flashing yellow arrow conducted, there is more information becoming available about the differences between this signal and the previously accepted method of allowing left turns at an intersection. The protected-permitted signal is typically displayed at an intersection with up to two through lanes and generally a protected signal is installed when the number of through lanes increases above two unless specific criteria is met. With the advent of larger arterials and more traffic on the highway networks, the push to operate these intersections at their maximum efficiency has resulted in more of these protected-permitted signals being present at these larger intersections, including the flashing yellow arrow. The core of the research that follows is a comparative analysis of the operation and parameters that affect the left turn movement of the intersection with larger geometry to that of the smaller geometry. The significant parameters of the left turn movement were examined through means of collecting, organizing and analyzing just over 68 hours of field data. This research details the determining of the significant parameters based on the generation of a simulation model of the protected left turn using Synchro, a traffic simulation package, and regression models using field driven data to determine the significant parameters for predicting the number of left turns that can be made in the permitted phase under specific operating conditions. Intuitively, there is an expectation that a larger intersection will not allow for as many permitted lefts as a smaller intersection with all conditions remaining the same. The conclusions drawn from this analysis provide the framework to understanding the similarities and the differences that are encountered when the intersection geometry differs and help to more efficiently manage traffic at signalized intersections. The work of this field promises to enhance the operations of the left turning movement for traffic control devices. With an understanding of the statistical models generated, a broader base of knowledge is gained as to the significant parameters that affect a driver's ability to make the left turn. A discussion of the statistical differences and between the models generated from the small and large geometry intersections is critical to drive further research into standards being developed for the highway transportation network and the treatment of these large signalized intersections. The exploration of specific parameters to predict the number of permitted left turns will yield results as to if there is more to be considered with larger intersections moving forward as they become a standard sight on the roadway network.
10

Propuesta de gestión del tránsito para la reducción del congestionamiento en la Av. Alfredo Benavides entre los tramos Ovalo Higuereta y Av. Velasco Astete en el Distrito de Santiago de Surco utilizando el programa de simulación Synchro 8.0

Alvarado Azurin, Vanessa Alexandra, Valle Azalde, Edson Ivan 05 September 2019 (has links)
El congestionamiento vehicular se ha convertido en un problema abrumador para los habitantes de la ciudad de Lima. Frente a este problema, existen alternativas de mejoras en el tránsito vehicular que permiten minimizar el tiempo perdido. Este problema se evidencia en muchas avenidas y calles de esta ciudad; sobre todo en horas pico. En ese sentido, la presente tesis, aporta una solución para ser aplicada en la avenida Alfredo Benavides entre los tramos del óvalo Higuereta y avenida Velasco Astete. Así mismo, la finalidad es aplicar la gestión de la oferta enmarcados a la optimización y coordinación de fases semafóricas y a la mejora de indicadores de tráfico, como son: los grados de saturación, niveles de servicio, demoras por espera y ciclos semafóricos en las intersecciones. Para este propósito, se utiliza el software para la simulación del tránsito a nivel mesoscópico Synchro 8, el cual permite modelar la situación actual para el análisis de la problemática y posterior propuesta de solución. En consecuencia, esta tesis evaluará el comportamiento vehicular de la red estudiada mediante la metodología HCM en donde no considera ciclistas y peatones. Finalmente, la propuesta de solución indica que si es posible optimizar y disminuir el congestionamiento vehicular del tramo en estudio. Esto sin alterar, de sobre manera, la infraestructura o generar mayores costos de implementación a la vía. / Traffic congestion has become an overwhelming problem for the population of the city of Lima. Faced with this problem, there are alternatives for improvements in vehicular traffic that minimize the time lost. This problem is evident in many avenues and streets of this city; Especially during rush hour traffic. To that extent, the purpose of this thesis provides a solution to be applied in Alfredo Benavides Avenue between sections of the Higuereta oval and Velasco Astete avenue. As well, the purpose is to apply the offer management of the demand framed in the optimization and coordination of traffic light phases and to the improvement of traffic indicators, such as: the saturation degrees, the service levels, waiting delays and traffic light cycles at intersections. For this purpose, we use the software for traffic simulation, the Synchro 8 at mesoscopic level, which allows modeling the existing situation for the analysis of the current problem and subsequent solution proposal. Consequently, this thesis will evaluate the vehicular behavior of the network studied, through the HCM methodology where it does not consider cyclists and pedestrians. Finally, the proposed solution indicates that if it is possible to optimize and improve vehicular congestion of the section under study. This without altering, exceedingly, the infrastructure or generating higher costs of implementation on the road. / Tesis

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