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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

What individual characteristics influence commuting distance and mode transportation? : A quantitative case study of Malmö, Southern Sweden

Hägg, Erika January 2014 (has links)
How mobile people are affects the accessibility which can lead to several benefits like better match in the labour market and economical gain in the labour market. How mobile people are and their accessibility are effected by several factors. The purpose with this study is to see what individual characteristics that influences the choice of mode of transport when commuting and the travelled distance. This was done with a quantitative method that analyzed the Travel Survey of Southern Sweden. The result was carried out from descriptive result and regressions that was analysed. Findings from the result shows that gender, income and origin of birth are the individual characteristic that affects the choice of mode and travelled distance the most. The result can indicate that the commuting is also effected by structures as well as the economical incitement. The most used mode for transport and the probability to go by car increases with the economical gain does as well.
2

Trip Reporting and GPS-based Prompted Recall: Survey Design and Preliminary Analysis of Results

Dumont, Josee 15 January 2010 (has links)
This trip reporting and GPS-based prompted-recall travel survey was undertaken to provide a better understanding of (a) demographic and behavioural differences between students with a home telephone land line and students without one (b) effects of carrying a GPS device on trip reporting (c) differences in trips reported and confirmed through a prompted-recall survey, and (d) performance of the TRIPS platform. The survey was designed and conducted at the University of Toronto between November 2008 and April 2009. It targeted mostly university students and returned 90 valid interviews. Participants were required to carry a GPS device with them for the two days surveyed. They were then asked to report their trips first, and then to confirm their recorded trips through the web-based prompted-recall tool, TRIPS. Preliminary analysis was conducted based on the reported data, and improvements to the TRIPS platform have been suggested.
3

Trip Reporting and GPS-based Prompted Recall: Survey Design and Preliminary Analysis of Results

Dumont, Josee 15 January 2010 (has links)
This trip reporting and GPS-based prompted-recall travel survey was undertaken to provide a better understanding of (a) demographic and behavioural differences between students with a home telephone land line and students without one (b) effects of carrying a GPS device on trip reporting (c) differences in trips reported and confirmed through a prompted-recall survey, and (d) performance of the TRIPS platform. The survey was designed and conducted at the University of Toronto between November 2008 and April 2009. It targeted mostly university students and returned 90 valid interviews. Participants were required to carry a GPS device with them for the two days surveyed. They were then asked to report their trips first, and then to confirm their recorded trips through the web-based prompted-recall tool, TRIPS. Preliminary analysis was conducted based on the reported data, and improvements to the TRIPS platform have been suggested.
4

Tool for querying the National Household Travel Survey data

Rathore, Akash January 1900 (has links)
Master of Science / Department of Computer Science / Doina Caragea / The goal of the project is to create a database for storing the National Household Travel Survey (NHTS) data, and a user interface to query the database. Currently, the survey data is stored in excel files in the CSV format, which makes it hard to perform complex analyses over the data. Analyses of interest to transportation community include comparisons of the trips made by urban household to those made by rural household, finding the average trip time spent based on ethnicity, the total travel time of a particular household, the preferred vehicle by a specific household, average time spent per shopping trip, etc. The tool designed for the purpose of querying the NHTS database is a Python-based Web application. Django is used as the Web framework for this project and PostgreSQL is used for the back-end purpose. The user interface consists of various drop-down lists, text-boxes, buttons and other user interface components that facilitate querying the database and presenting the results in formats that allow easy interpretation. FusionCharts Django-Wrapper and FusionCharts Jquery-Plugin are used to visualize the data in the chart form. A Codebook of the NHTS dataset is also linked for the reference purpose at any point for the user. The tool built in the project allows the user to get a deeper understanding of the data, not only by plotting the data in the form of line charts, bar charts, two column graph, but also by providing the results of the queries in the CSV format for further analysis.
5

Mode Choice Modeling Using Artificial Neural Networks

Edara, Praveen Kumar 27 October 2003 (has links)
Artificial intelligence techniques have produced excellent results in many diverse fields of engineering. Techniques such as neural networks and fuzzy systems have found their way into transportation engineering. In recent years, neural networks are being used instead of regression techniques for travel demand forecasting purposes. The basic reason lies in the fact that neural networks are able to capture complex relationships and learn from examples and also able to adapt when new data become available. The primary goal of this thesis is to develop mode choice models using artificial neural networks and compare the results with traditional mode choice models like the multinomial logit model and linear regression method. The data used for this modeling is extracted from the American Travel Survey data. Data mining procedures like clustering are used to process the extracted data. The results of three models are compared based on residuals and error criteria. It is found that neural network approach produces the best results for the chosen set of explanatory variables. The possible reasons for such results are identified and explained to the extent possible. The three major objectives of this thesis are to: present an approach to handle the data from a survey database, address the mode choice problem using artificial neural networks, and compare the results of this approach with the results of traditional models vis-à-vis logit model and linear regression approach. The results of this research work should encourage more transportation researchers and professionals to consider artificial intelligence tools for solving transportation planning problems. / Master of Science
6

Everyday mobility and travel activities during the first years of retirement / Vardagsmobilitet och resande under de första åren som pensionär

Berg, Jessica January 2016 (has links)
Mobility is central to living an independent life, to participating in society, and to maintaining well-being in later life. The point of departure in this thesis is that retirement implies changes in time-space use and interruption in routines, which influence demands and preconditions for mobility in different ways.  The aim of this thesis is to explore mobility strategies and changes in mobility upon retirement and how mobility develops during the first years of retirement. A further aim is to provide knowledge of the extent to which newly retired people maintain a desired mobility based on their needs and preconditions. The thesis is empirically based on travel diaries kept by newly retired people, and qualitative interviews with the same persons, and follow-up interviews three and a half years later. The results show that mobility is a way of forming a structure in the new everyday life as retirees by getting out of the house, either just for a walk or to do errands. Many patterns of everyday life remain the same upon retirement, but the informants also merge new responsibilities and seek new social arenas and activities. As a result, the importance of the car have not changed, but it is used for other reasons than before. After leaving paid work, new space-time constraints are created which influences demands for mobility. The study further shows that “third places” become important, especially among those who live alone, as they give an opportunity to being part of a social context and a reason for getting out of the house. The follow-up interviews revealed that declining health changes the preconditions for mobility. Daily walks had to be made shorter, and the car had to be used for most errands to where they previously could walk or cycle. However, mobility can also be maintained despite a serious illness and a long period of rehabilitation. / Mobilitet är en förutsättning för oberoende, delaktighet och välbefinnande när man åldras. Utgångspunkten i avhandlingen är att pensioneringen innebär tidsrumsliga förändringar och brott i rutiner som på olika sätt påverkar människors behov av att resa och deras förutsättningar för mobilitet. Syftet med avhandlingen är att utforska mobilitetsstrategier och förändringar i mobilitet i samband med pensioneringen samt hur mobiliteten utvecklas under de första åren som pensionär. Ambitionen är att öka kunskapen om i vilken utsträckning nya pensionärer upprätthåller en önskad mobilitet utifrån deras egna behov och förutsättningar. Avhandlingen baseras empiriskt på resedagböcker som nyblivna pensionärer har fört och kvalitativa intervjuer med samma personer, samt uppföljningsintervjuer tre och ett halvt år senare. Resultaten visar att mobiliteten är en strategi för att skapa en struktur i vardagen som pensionär genom att komma hemifrån, t.ex. för att ta en promenad eller för att uträtta ärenden. Många vardagsmönster behålls vid pensioneringen men informanterna finner också nya åtaganden och söker nya sociala arenor och aktiviteter. Betydelsen av bilen har inte förändrats men den används av andra anledningar än tidigare. Vid pensioneringen skapas andra tidsrumsliga begränsningar vilka inverkar på efterfrågan på mobilitet. Resultaten visa också att "tredje platser" blir viktiga, särskilt bland dem som lever ensamma, eftersom de ger en möjlighet att vara en del av ett socialt sammanhang och en anledning att komma hemifrån. Uppföljningsintervjuerna visade att förutsättningarna för mobilitet förändras när hälsan försämras. Promenaderna blir kortare och bilen används i högre utsträckning för de ärenden dit de tidigare kunde gå eller cykla. Men trots allvarliga sjukdomar och långa perioder av rehabilitering kan mobiliteten upprätthållas. / ERA-NET 2007 "Keep moving: improving the mobility of older persons" / Sentrip - Senior life transition points
7

Application of space time concept in GIS for visualizing and analyzing travel survey data

Lu, Xiaoyun 04 December 2013 (has links)
The classic time geography concept (space-time path) provides a powerful framework to study travel survey data which is an important source for travel behavior studies. Based on the space-time concept, this research will present a visualizing approach to analyze travel survey data. By inputting the data into GIS software such as TransCAD and ArcGIS and editing the needed information, this study will explain how to create 3D images of travel paths for showing the variation of trip distribution in relation to different social-economic factors deemed as the driving forces of such patterns. Also, this report will address the technical challenges involved in this kind of study and will discuss directions of future research. / text
8

The Transition to Alternative Fuel Vehicles (AFVs): an Analysis of Early Adopters of Natural Gas Vehicles and Implications for Refueling Infrastructure Location Methods

January 2015 (has links)
abstract: Alternative fuel vehicles (AFVs) have seen increased attention as a way to reduce reliance on petroleum for transportation, but adoption rates lag behind conventional vehicles. One crucial barrier to their proliferation is the lack of a convenient refueling infrastructure, and there is not a consensus on how to locate initial stations. Some approaches recommend placing stations near where early adopters live. An alternate group of methods places stations along busy travel routes that drivers from across the metropolitan area traverse each day. To assess which theoretical approach is most appropriate, drivers of compressed natural gas (CNG) vehicles in Southern California were surveyed at stations while they refueled. Through GIS analysis, results demonstrate that respondents refueled on the way between their origins and destinations ten times more often than they refueled near their home, when no station satisfied both criteria. Freeway interchanges, which carry high daily passing traffic volumes in metropolitan areas, can be appropriate locations for initial stations based on these results. Stations cannot actually be built directly at these interchange sites, so suitable locations on nearby street networks must be chosen. A network GIS method is developed to assess street network locations' ability to capture all traffic passing through 72 interchanges in greater Los Angeles, using deviation from a driver's shortest path as the metric to assess a candidate site's suitability. There is variation in the ability of these locations to capture passing traffic both within and across interchanges, but only 7% of sites near interchanges can conveniently capture all travel directions passing through the interchange, indicating that an ad hoc station location strategy is unlikely to succeed. Surveys were then conducted at CNG stations near freeway interchanges to assess how drivers perceive and access refueling stations in these environments. Through comparative analysis of drivers' perceptions of stations, consideration of their choice sets, and the observed frequency of the use of a freeway to both access and leave these stations, results indicate that initial AFV stations near freeway interchanges can play an important role in regional AFV infrastructure. / Dissertation/Thesis / Doctoral Dissertation Geography 2015
9

Communication technology and travel demand models

Börjesson, Maria January 2003 (has links)
Transportation planners have traditionally focused on physical travel only, and disregarded the fact that other modes of communication may influence travel demand. However, modern telecommunications are rapidly increasing the accessibility to activities that previously only could be reached by physical transportation. This development calls for methods to analyse interactions between telecommunications and transport systems. The objective of this thesis is to accomplish a better understanding of if and how impacts of information technology could be implemented in travel demand models. An important part of this issue is to investigate what kind of data that is needed. This thesis also aims at investigating whether the Communication Survey, KOM, collected by Swedish Institute for Transport and Communications, SIKA, can be used to improve transport modelling with respect to how modern telecommunications influence travel demand. KOM is a one-day travel and communication diary survey, including information on the respondents telecommuting habits as well as socio-economic status. One problem was the small sample size in KOM, which made the analyses uncertain. Since KOM is collected on a yearly basis, it is still possible to apply similar analysis methods within a few years, using a larger data set, which might enable extended analyses. The small sample in KOM available to date is best suited for general descriptive analyses of communication patterns in Sweden. The main conclusions of the paper are therefore connected to the methods and future data collection. The thesis includes three papers. The first paper tested a model approach that assumes substitution between travel and non-travel based communication, using the KOM database. Travel demand models are in general constructed as nested logit models with frequency, mode and destination choice levels. In the paper, non-travel based modes of communication were included in the choice set of such a model. The non-travel based modes of communication considered were Internet (and e-mail), ordinary mail and telephone contacts. The second and third papers investigate telecommuting. As a first step to reach the goal of forecasting telecommuting, the second paper examined the characteristics of current telecommuters by use of KOM. This was mainly accomplished by estimating a telecommuting adoption model of logit type. However, only 122 employees out of 7578 actually telecommutes full days at home. These telecommuters work primarily in information- and service-based industrial sectors concerned with computers, finance or communication. The difficulties in describing the utility of the telecommunications based alternatives (representing ”no travel”) concerned also the telecommuting adoption model. The third paper used data collected from a working site within the company Ericsson, located in the office district of Nacka Strand in Stockholm during the autumn 2002. The telecommuting frequency was substantially higher at Ericsson than in the workforce as a whole. The propensity to adopt telecommuting was modelled as a function of socio-economic variables and access to technical equipment, work task suitability and management attitudes, as perceived by the employees. The focus was to identify tools that the company can use to promote telecommuting, and to find incentives for the company to promote telecommuting. Technical equipment, suitable work tasks and managers attitude were identified as constraints for telecommuting. / <p>NR 20140805</p>
10

Estimation and Simulation of Daily Activity Patterns for Individuals Using Wheelchairs

Lant, Nathan John 01 June 2021 (has links)
Individuals who use wheelchairs or who have other mobility challenges often are unable to access modern mobility systems "“ including application-based ride hailing and on-demand microtransit. Even designing a system targeted at these users is challenging, given the limited prior analysis of their travel behavior and activity patterns. Simulation tools are used by cities around the world to understand novel and complex transportation systems, yet few are including the needs of users with disabilities in these simulation studies. This thesis examines the travel patterns of wheelchair users from the 2017 National Household Travel Survey and presents a model of daily activity pattern choice of respondents who self-identify as using a wheelchair. This thesis discusses the application of a wheelchair status variable in the activity-based travel demand model ActivitySim and measures its effect on individual and household daily activity pattern choice. Wheelchair use is estimated to reduce the utility of a work daily activity pattern by 1.9 points relative to a home pattern for full time workers and 3.4 for part time workers. Including the effect of wheelchair use in a regional daily activity pattern model resulted in 21.9 percent of wheelchair users changing to a home activity pattern relative to a base scenario not including wheelchair use. Lastly, the thesis evaluates the performance of an on-demand, accessible mode for users with wheelchairs in the agent-based microsimulation BEAM. This simulation showed that demand for such a service increases linearly with fleet size and wait time remains constant, though further scenario refinement and research is necessary.

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