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Projeto de redes otimizadas de transporte público por ônibus utilizando algoritmo genético. / Bus transit network design using genetic algorithm.Renato Oliveira Arbex 17 November 2014 (has links)
Esta dissertação trata do problema do projeto de redes de transporte público por ônibus, que consiste em estabelecer as linhas de ônibus a serem operadas e seus respectivos trajetos e frequências. Busca-se determinar uma rede de tal forma a minimizar custos de operadores e usuários, constituindo um problema multiobjetivo. O custo dos operadores é representado tanto pela frota como pela quilometragem total necessária para atender às frequências exigidas; já o custo dos usuários é representado pela soma dos tempos de espera, tempos de viagem dentro do veículo e eventuais penalidades de transferência. Dado tratar-se de um problema multiobjetivo, de natureza combinatória e complexo, é proposto um método de solução baseado na metaheurística Algoritmo Genético. O mesmo baseia-se na construção inicial de um banco de rotas viáveis, e cada solução proposta é formada selecionando-se um subconjunto de rotas deste banco para formar a rede. São aplicadas estratégias de busca por soluções viáveis nos operadores do Algoritmo Genético, devido à grande proporção de indivíduos inviáveis. O modelo é avaliado através de uma instância de teste da literatura e os resultados são comparados com os já obtidos em trabalhos anteriores. A melhor solução encontrada através do método descrito deste trabalho é superior às já reportadas na literatura. Uma análise de sensibilidade foi realizada para avaliar a influência de parâmetros de entrada do modelo na qualidade das soluções. Um Sistema de Visualização foi desenvolvido para representar graficamente as linhas de ônibus e demais variáveis das soluções. Sugere-se, ao final do trabalho, um conjunto de pesquisas futuras associadas à melhoria do modelo. / This dissertation addresses the public transport network design problem, which comprises determining the bus routes, their associated itineraries and frequencies. The network is designed as to minimize operators and users costs, creating a multiobjective problem. Operators costs are represented by the total fleet and mileage necessary to address required frequencies while user costs are represented by the sum of waiting times, in-vehicle travel times and possible transfer penalties. Given the complexity of this combinatorial and multiobjective problem, a solution method, based on the genetic algorithm metaheuristic, is proposed. Initially a database of feasible routes is built, and each proposed solution is formed by selecting a subset of routes from the database to form the network. Feasibility search strategies are applied inside genetic algorithms operators to make up for the large number of unfeasible individuals. The model is evaluated with a small network and the results are compared with those obtained in previous studies. The best solution attained with the present method is superior to previously published results. A sensitivity analysis was conducted to evaluate the influence of different model input parameters on solution quality. A Visualization System was developed to graphically represent the solutions bus lines and other variables. A set of future research ideas, related to the model improvement, are presented at the end of this study.
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Designing multimodal public transport networks using metaheuristicsFletterman, Manuel 16 January 2009 (has links)
The public transport system in South Africa is in a precarious state, capturing no more than 50% of the passenger market. The three public transport modes that are currently utilized—train, bus, and minibus-taxi—are competing for market share instead of complementing one another. Furthermore, most public transport networks have not been properly redesigned over the past three decades. Improvements were initiated reactively in the past: transit stops and routes were added or removed from the network when demand fluctuated. This reactive process has diminished the confidence of commuters in the public transport networks, forcing commuters to use private transport. A proactive redesign method is needed—one that includes all the modes of public transport, and anticipates an increase in demand and rapid development in geographic areas, while ensuring good accessibility to the network. Current network design models do not include multiple modes of public transport, and are based on the geographical layout of developed cities and their particularities, which makes them unsuitable for the South African environment with its unique land use disparities. This dissertation proposes a multimodal network design model that is capable of designing real world and large scale networks for the South African metropolitan areas. The City of Tshwane Metropolitan Municipality (CTMM) transport network area was used to develop and test the model, which consists of four components. The Geographic Information System (GIS) component has a central role in storing, manipulating, and exchanging the geographic data within the model. For the GIS the appropriate input data is identified, and a design for the geo-database is proposed. The Population Generation Algorithm (PGA) component translates the demographic data into point data representing the transit demand in the study area. The Bus Stop Placement Algorithm (BSPA) component is a metaheuristic that searches for near-optimal solutions for the placement of bus stops in the study area. A novel solution approach proposed in this dissertation uses geographic data of commuters to evaluate the bus stop placement in the study area. The Multimodal Network Design Algorithm (MNDA) component also employs a metaheuristic, enabling the design of near-optimal multimodal networks. The addition of multiple modes to the Transit Network Design Problem (TNDP) is also a novel and significant contribution. The two metaheuristic components are first tested on a test network, and subjected to a comprehensive sensitivity analysis. After identifying suitable parameter values and algorithm settings, the components are applied to the entire CTMM. / Dissertation (MSc)--University of Pretoria, 2009. / Industrial and Systems Engineering / unrestricted
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Modelo matemático para o projeto de redes cicloviárias integradas ao sistema de transporte público por ônibus em áreas urbanas /Oliveira, Stefano Petrini January 2020 (has links)
Orientador: Antônio Fernando Branco Costa / Resumo: O presente trabalho desenvolveu um modelo matemático que contribui para o projeto de redes cicloviárias conexas e integradas ao sistema de transporte público por ônibus em áreas urbanas, fazendo uso da Otimização Multiobjetivo (OM) por meio da Programação Linear Inteira Mista (MILP ou MIP). A investigação dos critérios de infraestrutura que influenciam a demanda cicloviária e que deveriam compor a modelagem matemática foi realizada por meio da Revisão da Literatura e cinco critérios identificados, referentes ao: Conforto, Segurança, Objetividade, Intermodalidade e Continuidade. Cada critério é composto por uma série de subcritérios, dezesseis no total, classificados como parâmetros de projeto de entrada e/ou de saída para o modelo matemático, segundo funções objetivos e restrições. Uma aplicação do modelo foi realizada em um caso real para cidade de grande porte, em São José dos Campos – SP, e obtidas soluções exatas com redes parcialmente conexas (abordagem 1) e redes totalmente conexas (abordagem 2), integradas aos pontos de parada de ônibus e as linhas de ônibus da região delimitada, por meio da linguagem de modelagem General Algebric Modeling System (GAMS) e o solver CPLEX. Os resultados obtidos foram aderentes a realidade da macrozona de tráfego na região estudada e contribuem para o planejamento urbano como validado pela Secretaria de Mobilidade Urbana de São José dos Campos. A análise de diversos cenários para o modelo matemático, ponderando os objetivos do modelo, pos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work created a mathematical model that contributes to design bikeway networks integrated to the public transport service by buses in urban areas, using the Network Multiobjective Optimization through Mixed by means of Mixed Integer Linear Programming (MILP or MIP). The investigation of the infrastructure criteria that influence cycling demand and that should set the mathematical modeling was carried out through the Literature Review and five criteria were identified, referring to: Comfort, Safety, Objectivity, Intermodality and Connectivity. Each criteria is composed of a subcriteria set, sixteen in total, which performed as input and/or output design parameters for the mathematical model, according to fitness functions and constraints. An application of the model was carried out in a real case in São Jose dos Campos city - Sao Paulo state, and exact solutions were obtained with partially connected networks (approach 1) and fully connected networks (approach 2), integrated to the stop points by bus and bus lines in the defined region, using the General Algebric Modeling System (GAMS) modeling language and the CPLEX solver. The results obtained were adherent to the reality of the traffic macrozone in the studied region and contribute to urban planning, as validated by the São José dos Campos Urban Mobility Secretariat. The analysis of several scenarios for the mathematical model, considering the model's objectives, made it possible to verify the behavior of the res... (Complete abstract click electronic access below) / Doutor
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Path Choice Estimation in Urban Rails : Asimulation based optimisation for frequency-based assignment model / Vägvalsestimering i Kollektivtrafiken : En simuleringsbaserad optimering för frekvensbaserade transportmodellAdolfsson, Alexander January 2022 (has links)
Transit system have a large importance in modern urban cities, with urban rail often acting as the central system with it efficient travel time and great capacity. As cities grow in population, so to does the usage of urban rail resulting in increased crowding on the platform and in the trains. Since crowding level is directly correlated to the experience of travel as well as a safety issue, much research has been done to improve it. Currently its common to utilise transit assignment models (TAM) to evaluate and research transit system but for them to work optimally requires weight parameters connected to perceived time spent on the journey. To get the weight parameters for a system requires surveys to be preformed which is costly and not always possible. Therefor its attractive to find these weights through optimisation using available data. Most transit system uses automated fare collection (AFC), which can be used to create origin-destination (OD) data, and automated vehicle location (AVL) together with link-load data. This project aims to develop a simulation-based optimisation (SBO) that automatically finds the weights for a frequency-based assignment model using OD and link-load as input arguments. The SBO will evaluate five different algorithm, genetic algorithm (GA), simulated annealing (SA), Nelder-Mead method (NM), simultaneous perturbation stochastic approximation (SPSA), and Bayesian optimisation (BO), using a fitness model based on KolmogorovSmirnov test. Synthetic data was implemented to evaluate the algorithms where result needed to be within a margin of error of the set weight. No algorithm was however able to converge during the simulation, therefor not optimising the weights to within the margin of error. A longer simulation was evaluated to see if the length needed to reach convergence was to short but achieved the same results. While the cause was not found, the standard deviation of the TAM could be the problem since the deviation was larger than the change of weight parameters achieved. Even if this project could not achieve its objective of developing a SBO method, it can be used for future research and work as a guide on further development on TAM research. / Transportsystem har en stor påverkan i moderna städer, specifikt tunnelbanan som ofta agerar som det centrala systemet med dess snabba transport samt stora kapacitet. Alltmedan städer växer i befolkning så ökar användandet av tunnelbanan vilket resulterar till trängsel både på plattformen och på tåget. Trängsel är väl studerat inom forskningen då den direkt påverkar den upplevda trivseln samt säkerheten på plattformen. Nuförtiden är det vanligt att använda sig av transport modeller för att undersöka och forska om transportsystemet men modellerna kräver viktparametrar kopplade till den uppfattade tiden man har för att fungera. Vanligtvis behöver man utföra undersökningar för att ta reda på vad viktparametrarna är men det är både dyrt och komplicerat. Därför vill man kunna få fram dessa vikter genom att optimera kända data. De flesta transportsystem använder sig av automatiska biljettsystem (AFC), vilket kan användas för att skapa start-stop (OD) data, och automatisk fordonslokalisering (AVL) tillsammans med länk-belastningsdata. Detta projekts syfte är att utveckla en simuleringsbaserad optimering (SBO) som automatiskt hittar vikterna för en frekvensbaserad transportmodell genom att använda OD- och länk-belastningsdata som argument. SBO kommer att undersöka fem olika algoritmer, genetic algorithm (GA), simulated annealing (SA), Nelder-Mead method (NM), simultaneous perturbation stochastic approximation (SPSA), and Bayesian optimisation (BO), tillsammans med en objektfunktion baserad på Kolmogorov-Smirnov testet. Syntetiskt data användes för att utvärdera algoritmerna, där resultatet behövde vara inom en viss marginal av de satta vikterna. Inga algoritmer konvergerade vilket resulterade att deras resultat inte var inom marginalen. Ett längre test var utfört då konvergensen kunde ha skett senare men det blev samma resultat som tidigare. Anledningen kunde inte finnas men sannolikt var det TAM standardavvikelse som var del av felet då den var större än en förändring av viktparametrarna skapade. Även om detta projekt inte kunde uppnå sitt mål kan den användas för fortsatt arbete inom området och vara som guide för framtida utvecklingar.
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