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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

Integrating Data from Multiple Sources to Estimate Transit-Land Use Interactions and Time-Varying Transit Origin-Destination Demand

Lee, Sang Gu January 2012 (has links)
This research contributes to a very active body of literature on the application of Automated Data Collection Systems (ADCS) and openly shared data to public transportation planning. It also addresses the interaction between transit demand and land use patterns, a key component of generating time-varying origin-destination (O-D) matrices at a route level. An origin-destination (O-D) matrix describes the travel demand between two different locations and is indispensable information for most transportation applications, from strategic planning to traffic control and management. A transit passenger's O-D pair at the route level simply indicates the origin and destination stop along the considered route. Observing existing land use types (e.g., residential, commercial, institutional) within the catchment area of each stop can help in identifying existing transit demand at any given time or over time. The proposed research addresses incorporation of an alighting probability matrix (APM) - tabulating the probabilities that a passenger alights at stops downstream of the boarding at a specified stop - into a time-varying O-D estimation process, based on the passenger's trip purpose or activity locations represented by the interactions between transit demand and land use patterns. In order to examine these interactions, this research also uses a much larger dataset that has been automatically collected from various electronic technologies: Automated Fare Collection (AFC) systems and Automated Passenger Counter (APC) systems, in conjunction with other readily available data such as Google's General Transit Feed Specification (GTFS) and parcel-level land use data. The large and highly detailed datasets have the capability of rectifying limitations of manual data collection (e.g., on-board survey) as well as enhancing any existing decision-making tools. This research proposes use of Google's GTFS for a bus stop aggregation model (SAM) based on distance between individual stops, textual similarity, and common service areas. By measuring land use types within a specified service area based on SAM, this research helps in advancing our understanding of transit demand in the vicinity of bus stops. In addition, a systematic matching technique for aggregating stops (SAM) allows us to analyze the symmetry of boarding and alightings, which can observe a considerable passenger flow between specific time periods and symmetry by time period pairs (e.g., between AM and PM peaks) on an individual day. This research explores the potential generation of a time-varying O-D matrix from APC data, in conjunction with integrated land use and transportation models. This research aims at incorporating all valuable information - the time-varying alighting probability matrix (TAPM) that represents on-board passengers' trip purpose - into the O-D estimation process. A practical application is based on APC data on a specific transit route in the Minneapolis - St. Paul metropolitan area. This research can also provide other practical implications. It can help transit agencies and policy makers to develop decision-making tools to support transit planning, using improved databases with transit-related ADCS and parcel-level land use data. As a result, this work not only has direct implications for the design and operation of future urban public transport systems (e.g., more precise bus scheduling, improve service to public transport users), but also for urban planning (e.g., for transit oriented urban development) and travel forecasting.
2

Bus Rapid Transit design parameters and their impact on travel times : A micro-simulation study of boarding and alighting through all doors and bus lanes

Berg Wincent, Boel January 2021 (has links)
Sweden has defined a national transportation objective that aim at making public transportation the most attractive option in more situations. One way of making public transportation mote attractive is to ensure that it is rapid. BRT stands for Bus Rapid Transit and is concept that ensures speed and reliability of public transportation buses through combined priority measures. However, accessibility measures for urban buses are often compromised and not prioritized politically. If the travel time saved for these measures can be estimated, then they are more likely to be implemented. Two components that have been defined for Swedish BRT were tested on a proposed BRT corridor in the city of Södertälje through microsimulation tool VISSIM. The two components that were tested was boarding and alighting through all doors and bus lanes, both median and curb side. The components were tested on a 3,2 km long corridor using the current actuated traffic signal that was currently in use. To test the measures a sensitivity analysis was carried out with three different levels of traffic and five different passenger levels for boarding and alighting. Only the impact on travel time for the bus was studied. The travel time savings from the measure boarding and alighting through all doors was 1 to 3 percent but only significant for the higher levels of boarding with an average of 12 to 15 boarding passengers per stop. The travel time savings of the curb side bus lane with actuated traffic signals was estimated to be up to 5 percent and for the median bus lane up to 11 percent in congested traffic conditions.
3

Estimativa do volume de passageiros ao longo de uma linha de transporte público por ônibus a partir da Geoestatística / Estimation of passenger volume along a bus transit line using Geostatistics

Marques, Samuel de França 15 February 2019 (has links)
A modelagem clássica da demanda por transportes ignora um importante aspecto normalmente presente na estrutura das variáveis de interesse: a autocorrelação espacial. Pesquisas recentes reconhecem e incluem tal característica à estimativa da demanda, mas há limitações referentes aos elementos básicos de tratamento utilizados nas abordagens. No intuito de superar alguns problemas e restrições associados aos estudos anteriores, o presente trabalho utiliza a dependência espacial entre as observações de viagens no intuito de gerar estimativas do volume de Embarques e Desembarques por ponto de parada, bem como Carregamento nos trechos, ao longo de uma linha de transporte público. Dados de uma pesquisa sobe/desce, realizada em oito linhas de ônibus da cidade de São Paulo, foram disponibilizados pela SPTrans, sendo que, selecionou-se a linha 856R-10 para compor uma análise do desempenho da Geoestatística, ferramental adequado para a estimativa de valores de variáveis em locais não amostrados, sobretudo em bancos de dados espacialmente dependentes. O processo de estimação foi realizado por meio da Krigagem Ordinária com distâncias euclidianas, técnica de interpolação geoestatística que, para sua aplicação, exige apenas o valor da variável em pontos do espaço e suas respectivas coordenadas geográficas. Posteriormente, tal método foi comparado às estimativas obtidas por meio da utilização de distâncias em rede ao longo da linha de ônibus. Os resultados obtidos, a partir da validação cruzada e métricas de aderência, apontaram um ajuste considerável dos valores observados e estimados para ambos os tipos de distância. Dessa forma, a investigação proposta confirmou, com sucesso, a viabilidade de aplicação da Geoestatística às variáveis de demanda por transporte público ao longo de uma linha de ônibus. Além disso, uma vez que a pesquisa sobe/desce exige recursos elevados para sua realização, os resultados destacam o potencial dos interpoladores geoestatísticos em eliminar a necessidade de execução do referido levantamento em todo o percurso da linha de ônibus, já que a Geoestatística garante estimativas aproximadas aos valores da pesquisa completa. / The classical modeling of travel demand overlooks an important aspect normally found in the variables of interest: spatial autocorrelation. Recent researches recognize and include this characteristic in travel demand forecasting, but there are limitations regarding the basic elements of treatment used in the approaches. In order to overcome some of the problems and constraints associated with previous researches, the present study relies on the spatial dependence between the observations of trips in order to generate estimates of the Boarding and Alighting passenger volume per bus stop and Loading in the stretches, along a public transport line, that would not be sampled for the survey occasion. Data from a passenger Boarding and Alighting survey carried out on eight bus lines in the city of São Paulo were made available by SPTrans, and line 856R-10 was selected to compose an analysis of the performance of Geostatistics, a tool that deals with the problem of scarce data and estimation in non-sampled places in the forecast of variables of public transport demand, especially in spatially dependent databases. The estimation process was performed by means of Ordinary Kriging with Euclidian distances, a geostatistical interpolation technique that, for its application, only requires the value of the variable in points of the space and their respective geographical coordinates. Subsequently, this method was compared to the estimates obtained through the use of network distances along the bus line. The results obtained, from cross-validation and measures of goodness-of-fit, indicated a considerable adjustment of the observed values to the estimated ones for both types of distance. Thus, the proposed research successfully confirmed the feasibility of applying Geostatistics to the variables of public transport demand along a bus transit line. Moreover, since the boarding/alighting survey requires high resources for its realization, the results highlight the potential of the geostatistical interpolators in eliminating the need to carry out the survey in the whole course of the bus line, since Geostatistics provides estimates similar to the values of the complete survey.
4

Occupant casualties in bus and coach traffic : injury and crash mechanisms

Albertsson, Pontus January 2005 (has links)
Background: The relevance of conducting this thesis is evident by the fact that bus and coach casualties have been “stubbornly stable” in Europe recent years and a need for investigating if a similar trend could be found in Sweden is therefore obvious. It was also important to add new knowledge to the bus and coach research in Sweden, since many areas were scarcely addressed. Aims: To describe bus and coach occupants’ injuries, crash and injury mechanisms generated in a traffic environment based on data from the medical sector. Additional aims were to investigate the injury reducing effect of a 3-point belt, the effect of cross-winds, and crucial factors in the emergency- and rescue response. Material and methods: Injury data analyses were based on a complete ten-year medical data set from a catchment-area with about 130,000 inhabitants. A number of crash studies with the scope in different crash phases were conducted by applying and elaborating the Haddon matrix as a framework. An additional framework, Protocol for Major Incidents was used in order to investi-gate the emergency- and rescue response to a severe coach crash. Results: Between the first and second five-year period, the incidence of injured in non-crash in-cidents was increased by 24%. In non-crash incidents, 54% were injured; 2/3 while alighting from a bus or coach. The pre-crash factor cross-wind, in addition to vehicle design, vehicle speed and road friction, was investigated in ten crashes. It was confirmed that cross-wind, in relation to vehicle speed and slippery road conditions, needs more attention. The importance of goods load-ing and passengers’ position in the bus, was indicated by the fact that a displacement of the cen-tre of mass rearwards with 10% increased the necessary coefficient of friction with, on average 45%, which in many cases corresponded to dry road conditions. Three Swedish rollover crashes were analysed with regard to the injury outcome, mechanisms and the possible injury reduction for occupants using a safety belt. A considerable increase in safety for occupants belted with 3-point belts was shown through limiting interior contacts, occupant interaction and the possibility of ejection. Crucial post-crash factors in the emergency- and rescue response showed that ordi-nary ways of working and equipment are not always useful and proper equipment for lifting a coach body is essential in the case of a rollover. Finally, the communication between the hospitals is important, and the telephone systems may be overloaded by calls from worried relatives and media. Conclusions: In non-crash events: Non-crash events constitute a majority of all bus and coach casualties with a high proportion of elderly female occupants among the MAIS 2+ injury cases. Boarding and, especially alighting causes many injuries to the lower extremities. In the pre-crash phase: Cross-winds do affect the safety of buses and coaches and requires more at-tention. Seat belt usage among bus and coach occupants has to be increased. In the crash phase: Rollover and ejection are the major causes behind serious and fatal injuries to bus and coach occupants, consequently, retentive glazing, pillars or rails need more attention. An upgrade from 2-point seat belts to 3-point seat belts yields an increase in the estimated injury re-duction from approximately 50% up to 80% for the MAIS 2+ casualties in a rollover crash. In the post-crash phase: In order to be able to lift a coach body proper equipment originated from experience and development is essential in a rescue operation of a crashed bus or coach. Fur-thermore, to improve the emergency response inside crashed coaches proper methods originated from experience need to be developed. Euro NBAP: Based on the results and conclusions generated in this thesis, a European New Bus and Coach Assessment Programme is suggested, which would provide bus and coach occupants with a assessment programme similar to the Euro NCAP.
5

Passenger Influence on Dwell Time : A Case Study on the Light Rail Transit Line Tvärbanan in Stockholm / Passagerares påverkan på uppehållstid : En fallstudie på Tvärbanan i Stockholm

Mir, Felix, Rahm, Fredrik January 2020 (has links)
This thesis conducts research on the light rail transit (LRT)-line Tvärbanan in Stockholm regarding punctuality of dwell time (DT), focusing on the influence passengers have on the mean and the variance of DT. The eight major stops during rush-hours are analyzed through a combination of quantitative and qualitative analysis. DT is proved to be affected by many factors in a complex setting, with vast differences between stops and between train types, proving that the infrastructure, the platform design, and the train design is important factors. The overall core problem is the non-uniformity of passengers, which is caused mainly by (1) the platform layout, especially the locations of entrances/exits, (2) placement of the train doors in relation to platform obstacles, (3) connections to other means of public transportation, and (4) the overall placement of the entrances/exits at other stops in the same direction. Stop-specific measures and suggestions of overall improvements are proposed in order to reduce the mean and the variation of DT. / Detta examensarbete undersöker hur uppehållstid påverkas av passagerare på light rail-linjen Tvärbanan i Stockholm, vilket har haft en historia av höga och oförutsägbara uppehållstider. De åtta största hållplatserna under rusningstid är analyserade genom en kombination av kvalitativa och kvantitativa studier. Uppehållstiden beror på många faktorer i en complex miljö, där stora skillnader finns mellan de olika hållplatserna och de olika tågtyperna, vilket är ett bevis att infrastrukturen, plattformsdesignen och tågdesignen är viktiga faktorer. Grundproblemet är att passagerare är ojämnt fördelade på plattformarna, vilket är orsakat av (1) plattformsdesignen, speciellt vart ingångar/utgångar är placerade, (2) vart tågdörrarna stannar i relation till objekt på plattformen, (3) förbindelser till annan kollektivtrafik och (4) hur ingångar/utgångar är placerade över hela linjen i samma riktning. Övergripande och hållplatsspecifika åtgärder för att minimera uppehållstiden presenteras i rapporten.

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