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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

Solving dynamic repositioning problem for bicycle sharing systems : model, heuristics, and decomposition

Wang, Tan, active 21st century 02 February 2015 (has links)
Bicycle sharing systems (BSS) have emerged as a powerful stimulus to non- motorized travel, especially for short-distance trips. However, the imbalances in the distribution of bicycles in BSS are widely observed. It is thus necessary to reposition bicycles to reduce the unmet demand due to such imbalances as much as possible. This paper formulates a new mixed-integer linear programming model considering the dynamic nature of the demand to solve the repositioning problem, which is later validated by an illustrative example. Due to the NP-Hard nature of this problem, we seek for two heuristics (greedy algorithm and rolling horizon approach) and one exact solution method (Benders’ decomposition) to get an acceptable solution for problems with large instances within a reasonable computation time. We create four datasets based on real world data with 12, 24, 36, and 48 stations respectively. Computational results show that our model and solution methods performed well. Finally, this paper gives some suggestions on extensions or modifications that might be added to our work in the future. / text
2

The Emergence of OFO Sharing Bicycles in Beijing : A case study of applying digital innovation

WANG, XIAOFENG, YU, WAI SHAN January 2020 (has links)
Digitalization is an important theme in Informatics research. Especially in today's digital society, people cannot live without the help of information technologies. The purpose of the study was to explore how the digitization process happened in the bicycle industry. The study was based on the background of bicycle-sharing system in Beijing and a qualitative methodology was followed. The findings show how bicycle-sharing system evolve step by step by applying advanced digital technologies. In the coming 5G era, organizations need to reconsider the situation of bicycle-sharing system and this research may give some references.
3

Bicycle Sharing in Developing Countries: : A proposal towards sustainable transportation in Brazilian median cities

Antunes Dias Batista, Edgard January 2010 (has links)
Bicycle-sharing programs are a new trend in urban transportation. The main difference of a bicycle-sharing program with a regular bicycle rental is that is possible to get a bicycle in one station and return it in any other station. There are many models of bicycle sharing, each model with its pros and cons. This study analyzes the bicycle-sharing models in order to build a proposal of a bicycle-sharing program suitable for Brazilian median cities. The study begins with an overview of bicycle transportation, followed by the analysis of different bicycle-sharing programs. The last chapter formulates a proposal of a bicycle-sharing program suitable for Brazilian median cities. This study uses both quantitative and qualitative methods. The analysis includes a case study on the bicycle-sharing program in Stockholm. This case study is based on interviews with the manager of the program in the company in charge, and with the responsible official in Stockholm municipality. A questionnaire was moreover handed out to users of the program. This case study is complemented with a questionnaire sent by email to managers of bicycle-sharing programs in some cities around the world, this in order to provide more examples on how bicycle sharing can be organized. Finally, another case study was carried out in a Brazilian median city in order to evaluate the local awareness concerning bicycle transport, and the possibility of implementing a bicycle-sharing program there. A questionnaire was handed out to a sample of the local population and an interview was made with the local transport authority. The analysis of all data results in a proposal for a bicycle-sharing program suitable for the Brazilian context. The proposal comprises the choices of bicycles, stations, equipment related to the hiring process and service vehicle. It includes a complete financial appraisal with the necessary capital for implementing and managing the program. It shows that it is possible to build an affordable bicycle-sharing program adapted to Brazilian median cities. The program will create job opportunities and can contribute to a changed view of bicycle transportation in these cities. The proposal could also be applied in countries with the same characteristics as Brazil.
4

Bicicletas próprias e compartilhadas na cidade de São Paulo: perfil dos usuários e características das viagens. / Understanding the use of private and shared bicycles in large emerging cities: the case of São Paulo, Brazil.

Benedini, Débora Junqueira 29 May 2018 (has links)
Esta dissertação apresenta uma pesquisa e uma série de análises realizadas com a finalidade de entender melhor o uso das bicicletas próprias e compartilhadas em São Paulo, cidade em que a infraestrutura cicloviária e os sistemas de bicicletas compartilhadas são recentes e ainda limitados. Através de análises descritivas e de modelos estatísticos, (1) foi realizada uma comparação das características dos usuários de bicicletas próprias com as dos usuários de bicicletas compartilhadas; (2) foi analisado o perfil dos ciclistas antes e depois da expansão da infraestrutura cicloviária e foram identificadas as diferenças comportamentais entre ciclistas recentes e experientes; (3) foram analisados os fatores associados à frequência do uso da bicicleta com motivo trabalho ou estudo e para demais finalidades e (4) foi analisada a escolha do uso da bicicleta compartilhada ou própria para uma determinada viagem. Os resultados indicam que a expansão da oferta de infraestrutura cicloviária parece estimular segmentos menos representativos da população, como mulheres e indivíduos de baixa renda, os quais não consideravam utilizar a bicicleta sem a existência de ciclovias. O tempo de viagem parece influenciar significativamente na frequência de uso de bicicleta, indicando que esse modo pode ser competitivo com os veículos motorizados em cidades grandes, densas e congestionadas. Também se observou que os sistemas de bicicletas compartilhadas desempenham um papel fundamental nas viagens multimodais e na atração de novos ciclistas. Os resultados servem de subsídios para tomadores de decisão na definição de estratégias que visam incentivar o uso da bicicleta. Assim, o estudo pode auxiliar na elaboração de políticas públicas voltadas para a bicicleta; por exemplo, incentivo à expansão dos sistemas de bicicletas compartilhadas ou melhorias e expansão da infraestrutura cicloviária nas cidades. / The current study presents a survey and a series of analyses performed in an effort to better understand the use of private and shared bicycles in Sao Paulo, a city where bicycle infrastructure and bicycle-sharing systems are recent and still limited. Using descriptive analysis and statistical models, we (1) compare the characteristics of private bicycle users and shared bicycle users; (2) analyze the profile of bicyclists before and after the expansion of dedicated infrastructure and identify behavioral differences between newcomers and experienced bicyclists; (3) analyze factors associated with frequencies of work and non-work bicycle trips, and (4) analyze the choice between using a private or a shared bicycle for a given trip. The results show that the expansion of bicycle infrastructure seems to stimulate underrepresented segments of the population, such as women and low-income individuals, to start cycling. Travel time seems to be an important predictor of bicycling frequency for both work and non-work purposes, suggesting that this mode can be very competitive with cars and transit in large, dense and congested cities. We also observe that shared bicycle systems play a fundamental role in multi-modal travel and in introducing new users to the bicycle mode. Results may subsidize policy making in defining strategies to stimulate the use of bicycles, such as introducing bike sharing systems and expanding and qualifying the cycling infrastructure.
5

Bicicletas próprias e compartilhadas na cidade de São Paulo: perfil dos usuários e características das viagens. / Understanding the use of private and shared bicycles in large emerging cities: the case of São Paulo, Brazil.

Débora Junqueira Benedini 29 May 2018 (has links)
Esta dissertação apresenta uma pesquisa e uma série de análises realizadas com a finalidade de entender melhor o uso das bicicletas próprias e compartilhadas em São Paulo, cidade em que a infraestrutura cicloviária e os sistemas de bicicletas compartilhadas são recentes e ainda limitados. Através de análises descritivas e de modelos estatísticos, (1) foi realizada uma comparação das características dos usuários de bicicletas próprias com as dos usuários de bicicletas compartilhadas; (2) foi analisado o perfil dos ciclistas antes e depois da expansão da infraestrutura cicloviária e foram identificadas as diferenças comportamentais entre ciclistas recentes e experientes; (3) foram analisados os fatores associados à frequência do uso da bicicleta com motivo trabalho ou estudo e para demais finalidades e (4) foi analisada a escolha do uso da bicicleta compartilhada ou própria para uma determinada viagem. Os resultados indicam que a expansão da oferta de infraestrutura cicloviária parece estimular segmentos menos representativos da população, como mulheres e indivíduos de baixa renda, os quais não consideravam utilizar a bicicleta sem a existência de ciclovias. O tempo de viagem parece influenciar significativamente na frequência de uso de bicicleta, indicando que esse modo pode ser competitivo com os veículos motorizados em cidades grandes, densas e congestionadas. Também se observou que os sistemas de bicicletas compartilhadas desempenham um papel fundamental nas viagens multimodais e na atração de novos ciclistas. Os resultados servem de subsídios para tomadores de decisão na definição de estratégias que visam incentivar o uso da bicicleta. Assim, o estudo pode auxiliar na elaboração de políticas públicas voltadas para a bicicleta; por exemplo, incentivo à expansão dos sistemas de bicicletas compartilhadas ou melhorias e expansão da infraestrutura cicloviária nas cidades. / The current study presents a survey and a series of analyses performed in an effort to better understand the use of private and shared bicycles in Sao Paulo, a city where bicycle infrastructure and bicycle-sharing systems are recent and still limited. Using descriptive analysis and statistical models, we (1) compare the characteristics of private bicycle users and shared bicycle users; (2) analyze the profile of bicyclists before and after the expansion of dedicated infrastructure and identify behavioral differences between newcomers and experienced bicyclists; (3) analyze factors associated with frequencies of work and non-work bicycle trips, and (4) analyze the choice between using a private or a shared bicycle for a given trip. The results show that the expansion of bicycle infrastructure seems to stimulate underrepresented segments of the population, such as women and low-income individuals, to start cycling. Travel time seems to be an important predictor of bicycling frequency for both work and non-work purposes, suggesting that this mode can be very competitive with cars and transit in large, dense and congested cities. We also observe that shared bicycle systems play a fundamental role in multi-modal travel and in introducing new users to the bicycle mode. Results may subsidize policy making in defining strategies to stimulate the use of bicycles, such as introducing bike sharing systems and expanding and qualifying the cycling infrastructure.
6

The Influence of Shared Mobility and Transportation Policies on Vehicle Ownership: Analysis of Multifamily Residents in Portland, Oregon

Bertini Ruas, Edgar 19 March 2019 (has links)
Since the beginning of the 21st Century, the world has seen the rapid development of the so-called "sharing economy" or collaborative consumption (Botsman, 2010). One of the first areas affected by the shared economy is vehicle ownership. With the emergence of several new providers of mobility services, such as Uber and car2go, there has been the promise of changes to the traditional way of owning and using a vehicle (Wong, Hensher, & Mulley, 2017). One potential consequence of shared mobility services is the reduction in vehicle ownership. At the same time, cities are trying to anticipate these changes by reducing the amount of space dedicated to parking, including parking requirements for residential developments. This thesis aims to assess the extent to which new shared mobility services (specifically, carsharing, bikesharing, and ridehailing) and travel demand management strategies (especially parking requirements and transit pass availability) relate to vehicle ownership among residents of multifamily dwellings. To do this, we use a web-based survey targeted to residents of multifamily apartments from Portland, Oregon. With these data, we built a multinomial logistic of the number of the vehicles owned as a function of socio-demographics, built environment, parking supply, transit passes, and three forms of shared mobility services. Results suggest that there is a strong association between shared mobility use and car ownership. However, it is not as significant as the effects of income, household size, distance to work, transit pass ownership, or even parking availability. Carshare use was negatively associated with the number of household vehicles, suggesting that it may be a useful tool in reducing car ownership. For respondents with higher education and income levels, increased carshare use was associated with fewer cars. Ridehail use, however, was not as clearly associated with reducing vehicle ownership and the effect was much smaller than that of carsharing. Parking availability in the building also has a significant and positive association with vehicle ownership. In sites with no parking available, there is an increased chance of the household owning less than two or more vehicles. However, this effect seems to disappear with the increased use of shared mobility. For all income levels, monthly use of ridehail and carshare between two and three times may decrease the odds of owning two or more vehicles. The use of both options, relaxing parking requirements and shared mobility availability, seems the best strategy to reduce vehicle ownership. In the short term, it is an alternative to those residents that decide to get rid of one or all cars but still are not ready to give up using cars. For the long term, a new relationship with vehicle ownership can be built now for the younger generation.
7

Mapping Stockholm's Bike-share Future : A GIS-based Analysis of Bicycle-sharing Stations in Stockholm / Kartläggning av Stockholms lånecykelsystem : En GIS-analys av lånecykelstationer i Stockholm

Hagwall, Rut January 2023 (has links)
In cities all over the globe, bicycle-sharing systems are being implemented as a way of promoting bicycling as the primary mode of transportation. Cities encourage the residents to bicycle as a way of improving local environments and reducing traffic congestion. A step in this direction is providing a bicycle-sharing system, which increases the accessibility and mobility in a city. For the availability of a bicycle-sharing system to be maximized, the locations of the docking stations must be carefully selected and analyzed. Several studies have been conducted where the availability of bicycle-sharing systems have been evaluated, using different approaches. However, no studies have been conducted in Stockholm on the newly established Stockholm eBikes bicycle-sharing system. Thus, this thesis aims to evaluate the location of bicycle-sharing stations and determine the most suitable locations of those in Stockholm. This is done through a GIS-based MCDM method which applies an Analytical Hierarchy Process to weigh the criteria that must be considered. The analysis is done in QGIS, an open-source GIS-software, with data from OpenStreetMap and local data sources. The results indicate that the suitability of the current bicycle-sharing stations in Stockholm is high considering the analyzed criteria. Further, a suggestion is given for locations where the suitability for bicycle-sharing stations is high. This suggestion proposes new locations in Stockholm where a bicycle- sharing station could increase the availability of the bicycle-sharing system as well as the mobility in the city.
8

Contribution à la modélisation et à l'analyse de performances des systèmes de vélos en libre-service en vue de leur régulation : « Une Approche basée sur les réseaux de Pétri" / Contribution to modelling, performance evaluation and regulation of self-service bicycle sharing systems : A Petri net approach

Benarbia, Taha 19 December 2013 (has links)
Le travail présenté dans cette thèse constitue une contribution originale à lamodélisation et à l'analyse de performances des systèmes de vélos en libre-service. De nombreuses villes en Europe ont suscité un intérêt considérable et un engouement à l'égard de ce nouveau mode de transport écologique (Vélib' à Paris, Vélov'v à Lyon, Bicing à Barcelone, ...) et dont les progrès technologiques ne cessent de les faire émerger dans les quatre coins dumonde. Contrairement aux systèmes de transport traditionnels, très peu d'étudesfondamentales ont été menées et pourtant, de nombreuses questions émergent, la principale étant celle d'un rééquilibrage (régulation) de la distribution de vélos dans les différentes stations afin de satisfaire au mieux les demandes des usagers. C'est dans ce cadre que s'inscrit cette thèse de doctorat portant sur la modélisation, l'analyse et l'évaluation de performances de ce mode de transport en libre service. Ce travail, basé sur les réseaux de Petri, est d'une aide précieuse pour la mise en oeuvre, l'exploitation et la régulation de ce type de systèmes.La complexité dynamique de tels systèmes, perçus comme des systèmes à événements discrets, nous a conduit au développement d'une approche à base d'une classe particulière de réseaux de Petri stochastiques ayant des arcs à poids variables pertinents aussi bien pour l'analyse que pour la simulation. Un ensemble de modèles et de méthodes d'analyse associées sont développés en vue de leur régulation, en prenant en compte différents paramètres de décision qui les caractérisent notamment le nombre de stations, la capacité de chaque station, les seuils de régulation, la capacité des véhicules de régulation, le type et/ou la fréquence de régulation choisi (périodique ou continue), …. En plus d'être paramétrables, les modèles proposés permettent d'étudier plusieurs configurations en fonction de différents modes de fonctionnement possibles (mode sans régulation, mode avec régulation, mode dynamique, mode statique, etc). La présentation de cette thèse comporte plusieurs illustrations et applicationspermettant d'aider le lecteur à la compréhension du travail développé.A notre connaissance, il s'agit d'un premier travail du genre dans la littérature sur les réseaux de Petri et plus généralement, l'un des premiers sur les systèmes de vélos en libre-service. / Public Bicycle-Sharing Systems (PBSS) have been appearing in more and more cities around the world in the last few years. Although their apparent success as an alternative form of public transportation mode, there are major challenges confronting the operators while few scientific works are available to support such complex dynamical systems to influence their economic viability and operational efficiency. One of the most crucial factors for the success of a PBS system is its ability to ensure that bicycles are available for pick up and vacant berths available for bicycle drop off at every station. In this thesis, we develop an original discrete event approach for modelling and performance evaluation of public bicycle-sharing systems by using Petri nets with time, inhibitor arcs and variable arc weights.
9

Bikesharing as an intervention: Does it increase cycling? : A controlled interrupted time series study from Helsinki, Finland

Rego, Padraig January 2019 (has links)
Background Bikesharing is a versatile intervention, that enables cheap and convenient cycling for urban populations, and according to recent literature, has a positive impact on health, safety and the economy. Many of these impacts are based on the assumption of a modal shift induced by bikesharing, i.e. implementing a Bicycle Sharing System (BSS) will increase population cycling. However, the evidence is inconclusive. The aim of this study was to evaluate if the intervention of implementing a BSS increases cycling. The study was conducted using bicycle count data from Helsinki between 2014 to 2018. Methods A controlled interrupted time series design was used in combination with segmented regression as the method. An intervention series and a control series were analysed separately. The slopes (trend) and intercepts (level) of pre-intervention (2014&2015) segments were compared with post-intervention segments (2016-2018). The same analysis was performed in both intervention series and control series.  ResultsThe results from the intervention series showed an increase of 105% in the level of the outcome after the implementation of the intervention. Simultaneously, the control series showed that the underlying trend of cycling remained largely unchanged during the whole study period (level increased by 3%). Stratified analysis supported these results in both intervention and control series.   Conclusion The analysis of the intervention series revealed, that the level of the outcome increased sharply after the intervention, implying that the intervention had an immediate effect. However, the lack of statistical significance in the analysis of the slopes made it impossible to determine if the effect was sustained.
10

Simulation and optimization models for scheduling and balancing the public bicycle-sharing systems / Modéles de simulation et d'optimisation pour l'ordonnancement et l'équilibrage des systèmes de vélos en libre-service

Kadri, Ahmed Abdelmoumene 11 December 2015 (has links)
Les enjeux du développement durable, le réchauffement climatique, la pollution dans les grandes villes, la congestion et les nuisances sonores, l'augmentation des prix de carburants, sont parmi des nombreux facteurs qui incitent les pays développés à l'innovation dans les transports publics. Dans ce contexte, l'introduction des systèmes de vélos en libre-service, au cours de ces dernières années, est une des solutions adoptées par de nombreuses grandes villes. Malgré leur succès fulgurant dans le monde entier, il existe peu d'études fondamentales sur ce type transport urbain. Pourtant, leur exploitation et leur management par des opérateurs soulèvent de nombreuses questions notamment d'ordre opérationnel. Dans ce contexte, cette thèse s'adresse aux problèmes d'ordonnancement et de rééquilibrage des stations de vélos en libre-service. Ce sont des problèmes cruciaux pour la qualité de service et la viabilité économique de tels systèmes. Le rééquilibrage consiste à redistribuer le nombre de vélos entre les différentes stations afin de satisfaire au mieux les demandes des usagers. Cette régulation se fait souvent par le biais de véhicules spécifiques qui font des tournées autour des différentes stations. Ainsi, deux problèmes d'optimisation difficiles se posent : la recherche de la meilleure tournée du véhicule de régulation (ordonnancement de la tournée) et la détermination des nombres de véhicules à utiliser (rééquilibrage des stations). Dans cette optique, les travaux de cette thèse constituent une contribution à la modélisation et à l'optimisation de performances des systèmes de vélos en libre-service en vue de leur rééquilibrage et leur ordonnancement. Plusieurs méthodes d'optimisation et ont été développées et testées. De telles méthodes incorporent différentes approches de simulation ou d'optimisation comme les réseaux de Petri, les algorithmes génétiques, les algorithmes gloutons, les algorithmes de recherche par voisinage, la méthode arborescente de branch-and-bound, l'élaboration des bornes supérieures et inférieures, etc. Différentes facettes du problème ont été étudiées : le cas statique, le cas dynamique, l'ordonnancement et le rééquilibrage avec un seul (ou multiple) véhicule(s). Afin de montrer la pertinence de nos approches, la thèse comporte également plusieurs applications réelles et expérimentations / In our days, developed countries have to face many public transport problems, including traffic congestion, air pollution, global oil prices and global warming. In this context, Public Bike sharing systems are one of the solutions that have been recently implemented in many big cities around the world. Despite their apparent success, the exploitation and management of such transportation systems imply crucial operational challenges that confronting the operators while few scientific works are available to support such complex dynamical systems. In this context, this thesis addresses the scheduling and balancing in public bicycle-sharing systems. These problems are the most crucial questions for their operational efficiency and economic viability. Bike sharing systems are balanced by distributing bicycles from one station to another. This procedure is generally ensured by using specific redistribution vehicles. Therefore, two hard optimization problems can be considered: finding a best tour for the redistribution vehicles (scheduling) and the determination of the numbers of bicycles to be assigned and of the vehicles to be used (balancing of the stations). In this context, this thesis constitutes a contribution to modelling and optimizing the bicycle sharing systems' performances in order to ensure a coherent scheduling and balancing strategies. Several optimization methods have been proposed and tested. Such methods incorporate different approaches of simulation or optimization like the Petri nets, the genetic algorithms, the greedy search algorithms, the local search algorithms, the arborescent branch-and-bound algorithms, the elaboration of upper and lower bounds, ... Different variants of the problem have been studied: the static mode, the dynamic mode, the scheduling and the balancing by using a single or multiple vehicle(s). In order to demonstrate the coherence and the suitability of our approaches, the thesis contains several real applications and experimentations

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