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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.
201

Demand for rail : transport options for the Waimakariri District : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Arts in Geography in the University of Canterbury /

Versteeg, L. O. January 2006 (has links)
Thesis (M.A.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 96-101). Also available via the World Wide Web.
202

India's demand for transportation

Weld, William Ernest, January 1920 (has links)
Thesis (Ph. D.)--Columbia University, 1920. / Vita. Published also as Studies in history, economics and public law, ed. by the Faculty of political science of Columbia University, vol. xc, no. 2 ; whole no. 206. Includes bibliographical references.
203

Traffic assignment and network analysis

Simhairi, Nather Zeki January 1987 (has links)
This thesis studies the transportation network, and is divided into three sections. Initially an algorithm is described which finds the user-equilibrium assignment for networks with linear congestion functions where the cost of travel on a link is dependent on the flow in the whole network. Secondly it investigates the sensitivity of the cost of travel and of the flow distribution in the network, to changes in the link congestion function. Combinatorial methods are used for evaluating the results of the sensitivity analysis. This is done with the aim of obtaining fast and efficient algorithms for the evaluation of cost sensitive and paradoxical links. Finally, for networks where the demand is elastic, it describes the catastrophic behaviour of the point representing the user-equilibrium flow distribution under certain cost conditions.
204

Aspects of driver behaviour in main road traffic streams

Chrissikopoulos, Vasilios January 1983 (has links)
Studies of composite headway models and platooning are reviewed and further results on time headways distribution are given. It is suggested that a three-population model is more satisfactory than a two-population model when short headways are of primary importance. Platoons were shown to occur randomly and the distribution of platoon sizes can be closely represented by a modified geometric distribution. It was also found that the distribution of headways in platoons was independent of speed at a given site, and members of platoons were shown to follow too closely in terms of the Highway Code advice; this close following behaviour was shown to be relatively greater at higher speeds. Observations showed that the deceleration behaviour of driver in a major road approaching a rural T-junction was affected by the T-junction (a) being unoccupied, (b) having vehicles waiting to cross and (c) having vehicles actually crossing. The results in case (a) were used to deconvolute the effects due to background in cases (b) and (c). Empirical results on the relationship between a measure of deceleration and other factors are presented. The deconvoluted values together with other observed data were used as input into a conflict simulation model. The output of the model consists of the number of precautionary and severe model conflicts to be expected in various circumstances. Results on driver gap-acceptance behaviour in adverse weather conditions at T-junctions are presented in appendix. No evidence of more cautious behaviour in wet weather was found.
205

Route choice characteristics of truckers in Southern California

Kothapalli, Sai 18 March 2017 (has links)
<p> This research study presents results from two independent surveys. The objective of the first survey is to determine and rank the factors that influences owner operators and truck companies of Southern California in route selection. The second surveys objective is to determine the value of time (VOT) and the value of reliability (VOR) for owner operators and truck companies of Southern California. The two surveys require responses that were obtained via phone calls and interviews at numerous truck companies, truck stops, and distribution centers of Los Angeles County. Respondents of both the surveys are classified into 48 categories based on their load type, trip distance, and truck axles and this resulted in 48 distinctive results for the two surveys. </p><p> For the first survey results, the techniques of fuzzy Analytical Hierarchical Process (AHP) is used on 91 owner operators and 45 truck company responses to rank 19 factors that contributes the most in route selection. The 19 factors are identified through literature studies. Results indicate that travel time, travel time reliability, and safety are the most influencing factors regarding the route selection. </p><p> Furthermore, in the second study, a modern Stated Preference (SP) survey is conducted on 517 owner operators and 248 truck companies of southern California to determine the VOT and VOR by applying linear regression. The average VOT is $58/hr. and the average VOR is $14/hr. 48 other distinctive VOT and VOR results gives a wider scope.</p>
206

Modeling Emission Footprints of Sustainable Land Use Policies at Local Jurisdictional Level

Dixit, Shweta 29 November 2017 (has links)
<p> Sustainable land use practices are redefining the urban form, mobility and therefore the transportation planning processes. Regional travel demand models are not sensitive to variables associated with land use practices at neighborhood level, such as transit-oriented developments (TOD). The first objective of this research is to quantify and compare land-use specific emission footprints at the household level (grams/household) for TOD and Non-TOD areas. Household travel survey data is used to stratify households into various TOD and Non-TOD zones. A comparison of means for emission footprints between Non-TOD and TOD land uses indicated that Non-TOD emission footprints are much higher than the TOD footprints and the differences are statistically significant. On the other hand, the differences amongst pairs of TODs and pairs of Non-TODs showed no statistical significance. </p><p> As its second major objective, the research proposes a disaggregate methodology (the Methodology) that is sensitive enough to sustainable land use policies and allows planners to quantify emission impacts of the policies at sub-regional level. At the center of the Methodology is a sub-regional travel demand model with finer TAZ resolution than what is represented in the regional model for the same sub-region. Different land use scenarios, including TODs, and transit patronages are represented in the experimental implementation of the Methodology for Loudoun County, VA, which is a rapidly growing suburban county in the metropolitan Washington D.C. area. Loudoun County&rsquo;s brisk growth, its emphasis on sustainable land use and transportation planning, and recent expansion of Metro rail service in to the County presented a unique opportunity to develop and experiment with TOD scenarios in the end-to-end (from planning to modeling) implementation of the Methodology. The effectiveness of the Methodology is demonstrated by the results, which show that emission reductions can be achieved by sustainable land use policy implementation at sub regional level. Furthermore, unlike the regional models, the Methodology is found to adequately model sensitivity of emissions to land use, area type and facility type as established by statistical validation using analysis of variance technique.</p><p>
207

Essays on Transportation Economics

Mohassel, Ahmad, Mohassel, Ahmad January 2017 (has links)
This dissertation includes three essays on Transportation Economics, which studies two important questions in Transportation Economics: first, what are the effects of public investment in transportation infrastructure and provision of transportation goods? and second, how the market mechanism can improve the provision of transportation goods? Chapter one and two address the first question and chapter three addresses the second question. In the first chapter, using disaggregated data on highway construction projects from the California Department of Transportation from 2001 to 2013 and matching project locations with traffic data, I investigate the effect of highway construction projects on reducing congestion. The average effect of spending per mile of highway on both average speed and the traffic flow for the affected highway segments is positive. The increase in speed for morning and evening peak hours is between 0.30-0.45 mph, which accounts for 20 thousand saved hours per day. The reduction in travel time alone accounts for a $1.06 billion benefit over a 30-year period. This amount is equivalent to 60 percent of the total project cost and does not include the reduction in vehicle accidents, travel time reliability, and the effect on users of alternative routes. In the second chapter, I empirically investigate the effects of highway lane closure due to construction activity on user cost. I use data from the California Department of Transportation (Caltrans) on locations and times of lane closures. These data are matched with disaggregated traffic data on hourly traffic speed and flow for each day for most traffic detectors over California highways. I then estimate a fixed effect model of the effects of lane closures on hourly average speed and hourly traffic flow. The results show heterogeneous effects of lane closures on different hours of the day. With most closures occurring over night, between 10 p.m. and 4 a.m., I find a reduction in average speed between 4.5 and 2 mph and an average reduction in the traffic flow of 258 vehicles per hour. I find social costs of lane closures to motorists that are well below the lane late reopening penalties imposed by Caltrans. In the third chapter, I investigate the effect of the SFpark project, a parking experiment on drivers' behavior that was conducted from April 2011 to May 2013 in San Francisco. Using hourly data on occupancy rates of on-street parking, I estimate the responsiveness of commuters to price changes at the block level that vary across locations and time of day. I use a fixed effects model to estimate the elasticity of the occupancy rate with respect to price changes. Moreover, I employ a regression continuity design (RDD) to estimate the effect of different price changes on demand. The elasticities range between -0.13 to -0.44 and vary by time of day and level of occupancy rate.
208

The spatial dynamics of the journey to work from a law and high income residential neighbourhood: A case study of Lower Town East and Rockliffe Park Village, Ottawa, Ontario, 1963

Nwala, Vincent Eze January 1968 (has links)
Abstract not available.
209

Measurement of the depth of equilibrium saltation layers

Cherewick, Harvey Richard January 1963 (has links)
Generally, the problem studied in this dissertation concerns a particular phenomenon encountered in conveying granular solids in gaseous-solids phase horizontal transport. The phenomenon is that at a certain velocity particles will no longer be conveyed, but will settle on the tube bottom forming a layer of stationary solids. Specifically, the goal of this study was to obtain a relationship between the depth of these layers and all the pertinent variables. This relationship was found to be [formula omitted] where: r is the layer depth d is the particle diameter D is the test section pipe diameter g is the local acceleration of gravity W is the solids flow rate/pipe cross-section area Pp is the particle density P is the air density The values or range of values of the pertinent variables for which the above relationship applies is as follows: d 0.032 to 0.201 inches D 2 and 3 inches W 0.68 to 33.3 lb/sec - ft² Pp 15 to 79 lb/cu.ft. P 0.073 lb/cu.ft. Tests were conducted using nearly spherical particles in 100° F, 0.5 psig air. Ambient temperature ranged from 70 - 72° F. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate
210

A transportation strategy for regional development

Ajayi, Peter Sunday January 1978 (has links)
Regional development is currently a major concern of governments in the developing countries - Nigeria included. The basic emphasis of regional development in these countries is the improvement of "quality of life for all citizens as development progresses" (Federal Republic of Nigeria: Third National Development Plan, 1975 - 80, Lagos, 1975, p. 291). In order to achieve this objective, emphasis is usually placed on the rural sector of the economy - where a majority of the citizens still live and are employed. The improvement of this sector is also the focus of this study. There are many strategies which are capable, at least theoretically, of improving conditions in the rural areas but the main emphasis of this study is the development of rural transportation as a means of developing the rural areas. Transportation is viewed as a necessity in any human settlement as people and goods have to move from one place to the other, for economic, social and political purposes. The first objective of this study is the establishment of the relationship between transportation and rural development - i.e. that there is a rural demand for transportation. If this demand exists, what mode of transport is most likely to satisfy that demand? At present in Nigeria, roads seem to be dominating other modes because of its characteristics. In this study, transportation is not seen as the sole agent for rural development. For a transportation strategy to be successful, it has to be coordinated with other development strategies. The problem of providing adequate rural transportation is identified as an institutional one. The institutional framework within which transportation is provided in Nigeria is then examined and problems identified, especially those related to rural transportation construction and maintenance. Especially apparent in the deficiencies of the existing administrative structure is the lack of coordination which it permits This lack of coordination of transportation policies exists between different ministries of the same government and between different levels of government - i.e. both horizontally and vertically. For this lack of coordination, it seems that the rural'roads are the most vulnerable. In view of this institutional problem, a modification of the existing structure is recommended, which gives greater emphasis to the development and maintenance of local roads in conjunction with the development of other modes of transportation for the country. The major modification is in favour of reducing the existing responsibi1ities of Local Governments in road transportation construction. This implies that the Federal and State Governments would have to take more shares if all types of roads are to be developed - i.e. providing good transportation in the rural areas. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

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