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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

Elastic travel demand analysis - An application to the West link railway in Gothenburg

Ravanbakhsh, Samyar January 2016 (has links)
Today the regional railway system lacks the capacity at the central station in order to meet the demand for both the public and freight transportation. The West link is a railway infrastructure project that is expected to both increase train commuting and also increase the train capacity at the central station in Gothenburg. The purpose of this thesis work is to do an elastic demand analysis between car traffic and the West Link in modal shift to determine how many travelers will change mode. Also traffic simulations will be made to investigate the traffic conditions around the stations when the West link has been implemeted. The simulation results showed that nowadays there are congestions on the major highways and some of the smaller low capacity roads. In the future, congestions will become more significant if no countermeasures are implemented like the West link. In the elastic demand analysis the results were overall around 47% – 51% on a demand of between 350 000 – 400 000 trips. As a conclusion it cannot be said whether the West link will ease the pressure on car traffic or not. The reasons are that the population will increase about 100 000 inhabitants until 2030 and the West link is assumed by the region to have this amount of travelers each day. This would result in the same traffic pressure as today with congestions in certain parts. If the number of West link users will be around 200 000, as the results of this thesis shows, then the West link will ease the pressure on car traffic.
2

A comparative study between Emme and Visum with respect to public transport assignment

Hildebrand, Cisilia, Hörtin, Stina January 2014 (has links)
Macroscopic traffic simulations are widely used in the world in order to provide assistance in the traffic infrastructure development as well as for the strategic traffic planning. When studying a large traffic network macroscopic traffic simulation can be used to model current and future traffic situations. The two most common software used for traffic simulation in Sweden today are Emme and Visum, developed by INRO respective PTV. The aim of the thesis is to perform a comparison between the software Emme and Visum with respect to the assignment of public transport, in other words how passengers choose their routes on the existing public transport lines. However, in order to make a complete software comparison the run-time, analysis capabilities, multi-modality, capacity to model various behavioural phenomena like crowding, fares etc. this will not be done in this comparison. It is of interest to study the differences between the two software algorithms and why they might occur because the Swedish Transport Administration uses Emme and the Traffic Administration in Stockholm uses Visum when planning public transport. The comparison will include the resulting volumes on transit lines, travel times, flow through specific nodes, number of boarding, auxiliary volumes and number of transits. The goal of this work is to answer the following objective: What are the differences with modelling a public transport network in Emme and in Visum, based on that the passengers only have information about the travel times and the line frequency, and why does the differences occur? In order to evaluate how the algorithms work in a larger network, Nacka municipality (in Stockholm) and the new metro route between Nacka Forum and Kungsträdgården have been used. The motivation for choosing this area and case is due to that it is interesting to see what differences could occur between the programs when there is a major change in the traffic network. The network of Nacka, and parts of Stockholm City, has been developed from an existing road network of Sweden and then restricted by "cutting out" the area of interest and then removing all public transportation lines outside the selected area. The OD-matrix was also limited and in order not to loose the correct flow of travellers portal zones was used to collect and retain volumes. To find out why the differences occur the headway-based algorithms in each software were studied carefully. An example of a small and simple network (consisting of only a start and end node) has been used to demonstrate and show how the algorithms work and why volumes split differently on the existing transit lines in Emme and Visum. The limited network of Nacka shows how the different software may produce different results in a larger public transport network. The results show that there are differences between the program algorithms but the significance varies depending on which output is being studied and the size of the network. The Visum algorithm results in more total boardings, i.e. more passengers have an optimal strategy including a transit. The algorithms are very similar in both software programs, since they include more or less parts of the optimal strategy. The parameters used are taken more or less into consideration in Emme and Visum. For example Visum will first of all focus on the shortest total travel time and then consider the other lines with respect to the maximum waiting time. Emme however, first focuses on the shortest travel time and then considers the total travel time for other lines with half the waiting time instead of the maximum wait time. This results in that less transit lines will be attractive in Emme compared to Visum. The thesis concludes that varying the parameters for public transport in each software algorithm one can obtain similar results, which implies that it is most important to choose the best parameter values and not to choose the "best" software when simulating a traffic network.
3

Application of Road Infrastructure Safety Assessment Methods at Intersections

Adedokun, Adeyemi January 2016 (has links)
Traffic safety at intersections is a particularly difficult phenomenon to study, given the fact that accidents occur randomly in time and space thereby making short-term measurement, assessment and comparison difficult. The EU directive 2008/96/EC introduced road infrastructure safety management, which offers a five layer structure for developing safer road infrastructure has been used to develop tools for accident prediction and black spot management analysis which has been applied in this work to assess the safety level of intersections in Norrköping city in Sweden. Accident data history from STRADA (Swedish Traffic Accident Data Acquisition) and the network demand model for Norrköping city were used to model black spots and predict the expected number of accidents at intersections using PTV Visum Safety tool, after STRADA accident classification was restructured and the Swedish accident prediction model (APM) was configured and tested to work within the tool using the model from the Swedish road administration (SRA). The performance of the default (Swiss) and the Swedish APM was compared and identified locations with the high accident records, predicted accident counts and traffic volumes were audited using qualitative assessment checklist from Street-Audit tool. The results from these methods were analysed, validated and compared. This work provides recommendations on the used quantitative and qualitative methods to prevent accident occurrence at the identified locations.
4

Backpacker-kulturen i Australien : en fältstudie av turismen i Australien

Röör, Satu January 2003 (has links)
<p>Resande har blivit en stor del av vårt samhälle och livsstilen för många unga människor idag. Min studie är ett försök att belysa vad som får oss att söka vår identitet i kulturer långt från våra egna, och hur dessa kulturer uttrycker sig själva. Hösten 2001 gick Sverige med i ett arrangemang som runt tio länder har med Australien, nämligen working/holiday-visumet. Detta och en rad andra aspekter har ökat resandet till denna del av världen. Den antropologiska metoden av fältobservationer och intervjuer med resenärer inbjuder till kunskap om hur denna arena av backpckers ser sig själva och vad som skapar denna kultur från ett inifrån-perspektiv.</p>
5

Assessment Of Scenarios For Sustainable Transportation At Metu Campus

Altintasi, Oruc 01 January 2013 (has links) (PDF)
Sustainable transportation aims encouragement of non-motorized (pedestrian and bicyclist) and shared-ride transportation modes instead of car-dependent travels. This is important for university campuses, as they have better chance to implement such policies in a rather controlled traffic network, and can set an example to other communities. Most of sustainable campus transportation programs boil down to reduction of car-based emission cost of campus mobility, which is always the first step in developing more sustainable transportation policies. Middle East Technical University (METU), Ankara has a large campus area and a population over 30,000 people. To develop sustainable campus transportation policies, it was important to quantify the current levels of mobility and vehicle emissions within the campus, which was the main motivation behind this study. This required determination of i) campus origin-destination matrix, ii) in-campus vehicle-km-travelled (vehicle-km), and iii) carbon emissions. Travel data obtained from different sources, including the gate entry with RFID systems enabled analysis of different user groups, such as academic and administrative personnel and students, separately. The traffic simulations were prepared in PTV VISUM, which provided both speed and vehicle-km values for road segments, and could represent multi-user group demand matrices in a single traffic assignment. Based on the base case mobility and emission values, more sustainable campus transportation policies were simulated in PTV VISUM, and assessed in terms of carbon emission impacts. Discouraging of private car usage by students seemed the first and simplest action.
6

Integration des ruhenden Verkehrs in die Verkehrsangebots- und Verkehrsnachfragemodellierung / Integration of parking traffic into transportation demand modelling

Schiller, Christian 04 October 2004 (has links) (PDF)
This work describe a theoretical model to integrate the parking traffic into the traffic demand modelling. Placed at program VISUM served from the PTV AG Karlsruhe for the traffic system modelling and rating, as well as the EVA demand model developed by LOHSE. / In dieser Arbeit wird ein modelltheoretischer Ansatz beschrieben, der neben dem fließenden Verkehr, auch den ruhenden Verkehr innerhalb der Verkehrsangebots- und Verkehrsnachfragemodellierung berechnet. Dazu dient das von der PTV AG Karlsruhe zur Verfügung gestellte Programm VISUM zur Verkehrsnetzmodellierung und Umlegung, sowie das von LOHSE entwickelte EVA-Modell zur Verkehrserzeugung, -verteilung und -aufteilung als Grundlage.
7

Estimation of Hourly Origin Destination Trip Matrices for a Model of Norrköping

Lindström, Agnes, Persson, Frida January 2018 (has links)
During the last century, the number of car users has increased as an effect of the increasing population growth. To manage the environmental and infrastructural challenges that comes with a more congested traffic network, traffic planning has become of higher importance to analyze the current traffic state and to predict future capacity challenges and effects of investments. These analysis and evaluations are commonly performed in different traffic analysis tools, where updated and realistic traffic demand needs to be provided to ensure reasonable results. In this thesis, a macroscopic model of Norrköping municipality constructed in the traffic demand modelling software Visum and a daily Origin-Destination(OD)-matrix is considered. The goal of this thesis is to produce a method that modify the current daily demand matrix into hourly demand matrices, called hourly target matrices, that represents a typical weekday. The goal is also to implement and evaluate the OD-estimation algorithm Simultaneous Perturbation Stochastic Approximation (SPSA) to obtain updated and valid demand matrices for the network model of Norrköping. The method of dividing the daily demand matrix into hourly target matrices is based on the paper by Spiess %26 Suter (1990). The method makes use of the available daily trip purpose matrices combined with hourly link flow observations from 96 links in a multiple linear regression model to obtain 24 hourly demand matrices. The resulting matrices are compared with the link flow observations and has different levels of R^2-fit, the maximum fit is 85.79 % and the minimum fit is 55.89 %. The average R^2-value is 72 %. The OD-estimation based on SPSA is performed on the AM and PM peak hours. The algorithm is implemented in Python scripts that are called from Visum where the traffic assignments is calculated. The result is an increase in R^2-value since the link flow difference between estimated and observed link flow is decreased. In total, the estimated link flows are improved by 7.4 % in the AM peak hour and 15.6 % in the PM peak hour. The total absolute change in OD-demand is 3 871 trips for AM peak hour and 6 452 trips for the PM peak hour. The estimated OD-matrices are evaluated by qualitatively visualizing the difference in heat maps and in the quantitative measure structural similarity index. The result is no major structural change from the hourly target matrices which verifies that the information used when the target matrices is produced still is considered. The total demand increased in both hours, with 505 respectively 2 431 trips and flows in some OD-pairs has a very high percental change. This was restricted by adding a penalty term to the SPSA-algorithm on the PM peak hour. The result of penalized SPSA is a much less increase of total demand as well as less percental change of the OD-flows. Though, this to a cost of not decreasing the link flow difference in the same magnitude.
8

Backpacker-kulturen i Australien : en fältstudie av turismen i Australien

Röör, Satu January 2003 (has links)
Resande har blivit en stor del av vårt samhälle och livsstilen för många unga människor idag. Min studie är ett försök att belysa vad som får oss att söka vår identitet i kulturer långt från våra egna, och hur dessa kulturer uttrycker sig själva. Hösten 2001 gick Sverige med i ett arrangemang som runt tio länder har med Australien, nämligen working/holiday-visumet. Detta och en rad andra aspekter har ökat resandet till denna del av världen. Den antropologiska metoden av fältobservationer och intervjuer med resenärer inbjuder till kunskap om hur denna arena av backpckers ser sig själva och vad som skapar denna kultur från ett inifrån-perspektiv.
9

Development of a Logit model of the transition effect to public transport

Ziedén, Therése January 2017 (has links)
The importance of traffic planning has, throughout the years, been in- creased, providing sustainable developments of traffic and infrastructural investments. The analysis of the current traffic situation and the evalua- tion of the effects of a future investment are crucial for the socio-economic benefits maintenance. These analyses and evaluations are most commonly done using traffic simulation models. One of the main traffic planning aims, nowadays, is to increase the number of public transport users against the number of private car users. This change in mode choice is called transition effect and could be beneficial both from an environmental and socio-economic perspective. This thesis aims to evaluate and improve the macroscopic traffic demand and transition model, used fot the city of Norrköping. Additionally, the thesis investigates if a general transition Logit model can be developed and which parameters are the most important to be included in a modal choice estimation. For the needs of this study, the traffic planning software Visum is used. The travel mode distribution is calculated by Logit models coded in Python-scripts integrated in Visum. Then, a traffic assignment is performed by Visum, computing new travel times as inputs to the Logit model and this iterative procedure continues until the system reaches an equilibrium. The thesis aims for a more reliable prediction of the transition effect by correcting the Python-scripts and estimating the parameters of the Logit model using data from surveys. The study shows that travel times is the most important factor for realistic results generation. However, the data used for the estimation of the Logit model parameters did not include sufficient information of travel times. The travel times had to be calculated, using two different methods, in order to be included in the estimation of new parameters. Although these methods could not provide any positive effects on the transition, they did prove the importance and significance travel time have when developing a traffic model. The result of the study invokes the importance to further develop the method of calculating travel times, when the input data is not sufficient, and shows that the travel time parameters are case specific.
10

Integration des ruhenden Verkehrs in die Verkehrsangebots- und Verkehrsnachfragemodellierung

Schiller, Christian 26 October 2004 (has links)
This work describe a theoretical model to integrate the parking traffic into the traffic demand modelling. Placed at program VISUM served from the PTV AG Karlsruhe for the traffic system modelling and rating, as well as the EVA demand model developed by LOHSE. / In dieser Arbeit wird ein modelltheoretischer Ansatz beschrieben, der neben dem fließenden Verkehr, auch den ruhenden Verkehr innerhalb der Verkehrsangebots- und Verkehrsnachfragemodellierung berechnet. Dazu dient das von der PTV AG Karlsruhe zur Verfügung gestellte Programm VISUM zur Verkehrsnetzmodellierung und Umlegung, sowie das von LOHSE entwickelte EVA-Modell zur Verkehrserzeugung, -verteilung und -aufteilung als Grundlage.

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