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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

A multi-criteria approach for the design and evaluation of demand responsive transport (DRT) services

Andrade, Miguel Jorge Raposo Nunes de January 2008 (has links)
Demand responsive transport services are nowadays an established and recognized way to provide better social inclusion to non-urban, low population density areas. The concept has its origins in the 70´s in the USA, but just recently the advances in technology made this type of service more economically attractive. Therefore is of no surprise that this kind of transportation is starting to be a serious option in several regions across Europe. The European Commission has been promoting projects to study and implement DRT services. One of these projects, MASCARA (deMand responsive trAnsport service for increasing Social Cohesion in urbAn/Rural Areas), involved a team from the Engineering School of the University of Porto, with the participation of the author. The MASCARA project was designed to promote the cooperation between several regions in Europe to share knowledge about DRT services, evaluating DRT pilots and DRT feasibility studies. This dissertation focus on the design of a framework to help this evaluation. The work resulted in combining two known multi-criteria methodologies, namely AHP and TOPSIS. Albeit these methods were designed to help choosing (ranking) between two or more possible scenarios, the proposed framework is able to evaluate and score one scenario situations. This work can be viewed as having two parts: the first one (from chapter 1 to chapter 4) deals with the design of the framework and methodology. From chapter 5 onwards the practical application is adressed. The author work was focused on the design and software implementation of the evaluation framework.
2

Determinants of customer satisfaction with a true door-to-door DRT service in rural Germany

Avermann, Niklas, Schlüter, Jan 25 September 2020 (has links)
The effects of demographic change and the lack of acceptance represent some of the main problems for the public transport infrastructure in rural areas. As a consequence, the development of new transport service options becomes especially relevant for rural communities. The Max-Planck-Institute for Dynamics and Self-Organization developed a new form of Demand Responsive Transport the EcoBus to examine the viability of new DRT systems in rural Germany. Our work draws on customer satisfaction data during the trial runs of the EcoBus. Based on the survey data, this paper develops regression models to explain the determinants of DRT customer satisfaction. Our main findings include the importance of waiting times and the ease of entry for overall customer satisfaction. Nevertheless, we found no evidence that the presence of other guests in the vehicle had any negative impact on customer satisfaction. Findings of other works that women are significantly more likely to use DRT services could not be validated from our data.
3

Accessibility, how it is understood by planners and experienced by citizens : Planners' and citizens' perceptions of how Demand Responsive Transport can increase accessibility in suburban areas.

Reinhardt, Albin January 2023 (has links)
Accessibility is a well-established concept that appears frequently in urban planning. It refers to the ability of citizens to actively participate in society. Nevertheless, inaccessibility is experienced in many places, which can lead to exclusion of citizens. Against this background, this master's thesis aims to center on the concept of accessibility and examine it from two perspectives - strategic urban planners and individuals. The thesis examines how accessibility is interpreted by strategic urban planners in the two suburban municipalities of Botkyrka and Huddinge and how it is experienced by a group of “low-skilled” workers in an area where there are identified shortcomings in traffic planning. The thesis studies how this group experiences their accessibility in their daily commute before and after they test a Demand-Responsive Transport (DRT) service. The theoretical framework consists of the concepts of accessibility strategies, transport and accessibility, objective accessibility, perceived accessibility, accessibility barriers and social exclusion, which are used to analyze the two different perspectives. The results show that strategic planners view accessibility as the relationship between citizens and destination points, and that inaccessible places are mainly associated with rural or sparsely populated areas. At the same time, the thesis shows that the workers experience inaccessibility in their daily trips, despite living in surrounding municipalities. The results also show the identified potentials and risks of DRT in suburban environments from the perspective of both strategic planners and individuals. The results show that DRT reduced travel times for the workers. Furthermore, perspectives such as reliability, safety and equity are highlighted as important aspects in the design of DRT services.
4

Information flows in Demand Responsive Public Transport : Interactivity, information, and flexibility in a modern ridesharing service

Hamnebo, Karl, Askfelt, Oscar January 2021 (has links)
The focus of this thesis is to study what and how information flows can be used to improve Demand responsive transport (DRT) systems by understanding potential users and how they could be willing to participate in DRT to a higher degree. The viewpoint of this thesis tends to lean towards a DRT service of a public transport type. This thesis studies users in relation to what interaction and information they perceive to be needed in dealing with a DRT service and the different pros and cons with various approaches. The study gathers information by performing adapted qualitative interviews with a select number of users between the ages of 20-35. The participants give their views on three DRT scenarios and reflect on DRT in general as a concept presented to them through a tangible mocked-up interactive prototype.  The thesis makes several distinct findings. The importance of pricing a DRT service correctly is vital to the users, as several participants in the study relied on pricing for decision-making. It also finds that the usage of zones as nomenclature is confusing to many users. The services must be dependable and punctual to both attract users, keep users, and build trust among the general populace. This study shows that DRT services could be a difficult concept to introduce to users. DRT could be introduced as a complement or as an alternative to conventional public transport. An important factor is a well-designed flow of information in the application to keep the user engaged and involved. It is shown that the usability of the application is a cornerstone for a theoretical DRT service to excel. Context is important where DRT and ridesharing would have a higher success rate. Nighttime in urban areas could be a niche market, due to the irregularity, delay, or interruption of regular public transport services at these hours.
5

Optimal operating strategies for first/last mile feeder services due to the arrival of automated vehicles : Case study: suburban areas around tunnelbana, pendeltåg and lokalbana corridors in Stockholm

ROMERO LÓPEZ, ALBERTO January 2020 (has links)
With the improvements of the vehicle technology related with connectivity, sharing, automation and electrification and as a solution to the problems that cities are facing, such as an intense population growth and pollution, there are new forms of mobility that are or will be created within the framework of the future mobility. In this context, the arrival of driverless autonomous vehicles will provoke an irreversible change supporting the implementation of new forms of mobility or improving the existent. One factor that will help to do feasible the improvement of the existent mobility is the reduction of costs due to the arrival of autonomous vehicles, what will make ondemand transportation competitive under certain circumstances when comparing costs between it and fixed route systems. This thesis studies for the case of the metro/rail corridors in the metropolitan area of Stockholm which areas are suitable to implement Demand Responsive Transport (DRT) according to urban configuration and access to transit parameters. Once the identification is done, a model to compare between two different operating strategies for feeder services is applied to obtain which one is optimal under different stages of development of the technology related with the vehicles in the fields of automation and electrification. The model used, with additions to existing ones to adapt it to the use of it to real scenarios, gives numerical results for the four considered stages, showing the importance of the travel demand and the street sinuosity on the results and selection of the optimal. The method and criteria developed contributes to have a clear identification of the areas in which the implementation of the DRT services would be feasible in a future mobility scheme.
6

Modelling and Simulating Demand-Responsive Transport

Dytckov, Sergei January 2023 (has links)
Public transport is an efficient way to transport large volumes of travellers. However, there are systemic issues that make it hard for conventional public transport to provide efficient service on finer levels, like first- and last-mile problems or low-demand areas. One of the potential solutions that has been getting a lot of attention recently in research and real practice is Demand-Responsive Transport(DRT). The main difference between demand-responsive services and conventional public transport is the need for explicit requests for a trip from the travellers. The service then adapts the routes of the vehicles to satisfy the requests as efficiently as possible. One of the aims of such transport services is to combine the flexibility and accessibility of travel modes like taxis and private cars with the efficiency of buses achieved through ride-sharing.DRT has the potential to improve public transport in, for example, low population density areas or for people with mobility limitations who could request a trip directly to a home door. Historically DRT has been extensively used for special transportation while the recent trend in research and practice explores the possibility of using this service type for the general population.The history of DRT shows a large degree of discontinued trials and services together with low utilisation of vehicles and limited efficiency levels. In practice, this leads to measures restricting the trip destination, times when service is available, or eligibility to use the service at all in case of special transport DRT. Due to the limited use of DRT services, there is little data collected on the efficiency of the service and transport agencies exploring the possibility of introducing this new service type face difficulties in estimating its potential.The main goal of this thesis is to contribute towards developing a decisionsupport method for transport analysts, planners, or decision-makers who want to evaluate the systemic effect of a DRT service such as costs, emissions and effecton society. Decision-makers should be able to evaluate and compare a large variety of DRT design choices like booking time restrictions, vehicle fleet type, target trip quality level, or stop allocation pattern. Using a design science, we develop a simulation approach which is evaluated with two simulation experiments. The simulation experiments themselves provide valuable insight into the potential of DRT services, explore the niche where DRT could provide the most benefits and advocate taking into account the sustainability perspective for a comprehensive comparison of transport modes. The findings from the simulation experiments indicate that DRT, even in its extreme forms like fully autonomous shared taxis, does not show the level of efficiency that could result in a revolution in transportation — it is hard to compete inefficiency with conventional public transport in urban zones. However, in scenarios with lower demand levels, it could be more efficient to replace conventional buses with a DRT service when considering costs and emissions. We also show that, when integrated with conventional public transport, DRT could help alleviate the last-mile problem by improving accessibility to long-distance lines. Additionally, if car users are attracted to public transport with the help of DRT, there is a potential to significantly reduce the total level of emissions. The simulation results indicate that the proposed simulation method can be applied for the evaluation of DRT. The implementation of trip planning combining DRT and conventional public transport is a major contribution of this thesis. We show that the integration between services may be important for the efficiency of the service, especially when considering the sustainability aspects. Finally, this thesis indicates the direction for further research. The proposed simulation approach is suitable for the estimation of the potential of DRT but lacks the ability to make a prediction of the demand for DRT. Integration of a realistic mode choice model and day-to-day simulations are important for making predictions. We also note the complexity of the DRT routing for large-scale problems which prohibits a realistic estimation with simulation and the efficient operation of the service.
7

Analyse et modélisation multi-agents de transports flexibles : Comparaison de services français et sénégalais / Analysis and multi-agent simulation of flexible transports : Comparison between french and senegalese services

Lammoglia, Adrien 14 October 2013 (has links)
Organiser le secteur du transport pour offrir des solutions de déplacement efficaces est aujourd'hui un enjeu capital pour nos sociétés. La flexibilité, tendant à augmenter la qualité de service, constitue un des leviers pour améliorer les transports. Diverses formes de flexibilité apparaissent en effet dans l'offre actuelle. Dans cette thèse, nous appréhendons plus particulièrement des services opérant dans deux contextes sociétaux distincts :• d'une part, dans un pays industrialisé (la France) où le recours aux transports publics reste minoritaire car la dépendance à l'automobile est toujours très forte ;• d'autre part, dans un pays en voie de développement (le Sénégal) possédant des moyens financiers limités, mais où l'usage des transports collectifs est généralisé, impliquant une grande diversité des modes et une atomisation de l'offre.Nous proposons ainsi d'analyser et de comparer le fonctionnement des transports informels et artisanaux sénégalais (tels que les taxis collectifs) avec celui des systèmes considérés comme plus modernes en France, pour lesquels les capacités d'auto-organisation des individus ont été progressivement remplacées par des systèmes d’information et de communication de haut niveau technologique et logistique. Ces innovations semblent apporter plus d'immédiateté au transport flexible, mais nécessitent en contrepartie un encadrement fort de la part des autorités publiques générant des contraintes réglementaires et spatiales. À l'opposé, les services spontanés et dérégulés qui sont proposés au Sénégal bénéficient d'une plus grande souplesse, au détriment de la sécurité des passagers.L'objectif de la thèse est d'analyser ces services, les modéliser et les simuler afin d'évaluer les apports de la flexibilité. D'un point de vue méthodologique, notre recherche est basée sur un ensemble de modèles inspirés des transports observés en France et au Sénégal, puis implémentés en Systèmes Multi-Agents (SMA) dans l'environnement Netlogo. Certains modèles sont issus d'une analyse fonctionnelle de terrain et d'autres sont plus théoriques. Par l'analyse du comportement d'agents réalisant ces services en concurrence et/ou en coopération, nous identifions d'abord des seuils et des conditions de mise en œuvre en termes d'efficacité et de couverture spatiale. En simulant les modèles sur plusieurs configurations spatiales, nous explorons ensuite leur fonctionnement et nous analysons les atouts et les faiblesse de chacun. Nous les simulons ensuite simultanément pour évaluer leur capacité de complémentarité. Cela nous permet in fine de confronter des systèmes de transports analogues à ceux observés dans les deux contextes sociétaux et d'établir une grille de comparaison en fonction des niveaux de flexibilité identifiés.. / Organizing and developing efficient urban transportation services is a key issues for actual society. The flexibility appear as an important criteria to improve the services quality and to offer attractive transportation solutions. Different forms and levels of flexibility exist in the actual supply-side. For this research we focus on flexible transports operating in two society contexts:• in an industrial country (France) where the using rate of public transportation services islow because the automobile dependency is still high;• in a developing country (Senegal), where the financial resources are limited and theutilisation of public transports is generalized, leading to a diversity of services and anatomic supply-side. More precisely, we compare the functioning of senegalese para-transit services (as collectivetaxis) with french technological systems (as Demand Responsive Transport (DRT)). In France, auto-organization skills and collective behaviours have been replaced by the utilisation of highlevel information, communication and logistic systems. These innovations bring more immediacy and spontaneity in public transports, but it needs a strong supervision from authorities, causes regulatory ans spatial constraints of servicing. In contrast, in Senegal deregulated services benefit to more spontaneity and suppleness to the detriment of the passengers security.The objective of the thesis is to analyse, model and simulate these services to evaluate thecontributions of the flexibility. Regarding the methodology, our study is based on a group ofmodels inspired by transportation systems observed in France and Senegal and implemented inMulti-Agent Systems (MAS), in the NetLogo environnement. Some models are derived from a functional analysis and others are more theoretical. By analysing behaviours of agents performing these services in concurrency or incooperation, we highlight some thresholds and optimal conditions of coverage. Simulations invarious spatial configurations allow to explore model functioning and to analyse their strengthsand limitations. Then, we simulate models in parallel (two models by simulation) to evaluate their complementarity. We compare these combined models, all of them representing transportation services observed in two different contexts. Finally, we build a comparison matrix of clues according to the model performance and flexibility levels. To conclude, this research leads to a valuable reflection on how could be designed flexible transport services in the future.
8

Poptávková autobusová doprava v podmínkách České republiky / Demand responsive transport in the Czech Republic

Škripko, Jindřich January 2017 (has links)
This Master´s thesis deals with demand responsive transport that covers various forms of transport services that are characterised by realization of the bus ride only if there is demand. The thesis is practically focused. The purpose of the thesis is to check the suitability of setting a demand responsive transport system in the Králíky region from the transport and economic point of view. The analytical part describes existing demand responsive transport systems in the Czech Republic and in Europe and their compliance with the Czech legislation. The practical part applies this knowledge on design of a concept of demand responsive transport in Králíky region including the operational cost calculation.
9

Estimation et analyse spatiales des émissions de polluants de transports individualisés : évaluation des performances environnementales d'un Transport à la Demande / Spatial estimating and analyse of exhaust emissions from individual transports : Assessment of the environmental performance of a demand responsive transport

Prud'homme, Julie 25 October 2013 (has links)
Le Transport A la Demande (TAD) est un système de transport qui propose un usage collectif des véhicules automobiles, par opposition à l’usage des véhicules personnels (VP). Situé entre le fonctionnement des taxis et celui des transports en commun classiques, il propose un service à la fois flexible dans le temps et dans l'espace à la manière des taxis, favorisant le partage des véhicules, comme les transports en commun. Il est ainsi présenté comme une réponse pour une mobilité durable. Dans les esprits, les TAD sont souvent associés à une réduction des émissions de polluants et sont mis en place principalement dans des territoires ruraux. Pourtant, le simple regroupement effectué par les TAD suffit-il pour que la mise en place des TAD soit profitable à l’environnement ? Dans ce travail de recherche de doctorat, un outil d’évaluation de l'impact environnemental d’un système de Transports À la Demande (TAD) destiné aux collectivités territoriales a été mis au point. Pour que choix soit durable, au sens du développement durable, le service doit être le plus adapté au contexte local en minimisant les émissions de substances dans l’atmosphère proche tout en conservant une qualité de service suffisante pour concurrencer l'usage du véhicule personnel. Un paramètre, directement impliqué dans les émissions de polluant, est souvent négligé dans les approches : le réseau routier. On cherche donc à identifier des lois et des seuils relatifs aux émissions de polluants produites par le fonctionnement d’un TAD : dans quelle mesure le réseau routier influe-t-il sur les performances environnementales des TAD ou sur la capacité de regroupement des clients dans les véhicules ? Selon quelles caractéristiques de service (fenêtres de temps autorisées) ? Plus globalement, est-ce que l’optimisation d’un même type de TAD est équivalente d’un réseau routier à un autre, du point de vue des émissions de polluants ? Aucun outil intégré permettant d’effectuer cette tâche n’étant disponible, nous avons mis au point une chaîne de traitement géomatique permettant d’estimer les quantités de polluants émises sur les tronçons de route dans le cadre du fonctionnement particulier des TAD et de les cartographier pour analyser leur répartition spatiale. Cet outil associe un SIG à un modèle d’émission que nous avons adapté à notre problématique (GREEN-DRT). Il est ressorti des différents scénarios simulés que les TAD ne sont pas systématiquement une solution pertinente dans un objectif de réduction globale des émissions de polluants sur un territoire donné. Le constat de la faible pertinence environnementale de ce mode de transport sur les territoires les moins denses (type zones rurales) a été fait, pourtant, ce sont sur ces territoires que les TAD sont développés en France. À défaut d’engendrer une réduction des émissions, ils ont souvent un rôle social important en se positionnant non pas comme une alternative à la voiture personnelle, mais en permettant à des populations captives de se déplacer. Il s’agit de ce cas de minimiser les émissions de polluants provoquées par le fonctionnement du service. / The Demand Responsive Transport (DRT) is a transportation system which offers a collective use of motor vehicles, in opposite of personal vehicles use. Between the functioning of taxis and classical public transport, it offers a service that is flexible in time and space like taxis, promoting the sharing of vehicles, like public transports. It is why it is present as a solution for a sustainable mobility. In the minds, DRT are often associated to a reduction of exhaust emissions and so are developed in rural areas. However, is grouping travellers enough to make DRT gainful for environment?In this doctoral research, an assessment tool of the environmental impact of DRT systems has been developed. To ensure that choice is sustainable in the sense of sustainable development, the service must be adapted to the local context by minimising emissions of substances in the near atmosphere while maintaining a sufficient quality of service when competing against personal vehicle use. A parameter directly involved in pollutant emissions, is often overlooked in approaches: the road network. We therefore search for identify laws and thresholds relating to pollutant emissions generated by the functioning of a DRT: how the road network does it affect the environmental performance of DRT or on the skill to grouping customers in vehicles? Depending on what service features (time windows allowed)? More generally, is that the optimization of the same type of DRT is equivalent to a road network to another, from the perspective of pollutant emissions? As any integrated tool to perform this task is available, we have developed a geomatics processing to estimate the quantities of pollutants emitted on road sections within the particular functioning of DRT and to cartography it to analyse their spatial distribution. This tool combines a GIS to an exhaust emissions model that we have adapted to our questioning (GREEN-DRT).

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