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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.
41

Harnessing Big Data for the Sharing Economy in Smart Cities

Shou, Zhenyu January 2021 (has links)
Motivated by the imbalance between demand (i.e., passenger requests) and supply (i.e., available vehicles) in the ride-hailing market and severe traffic congestion faced by modern cities, this dissertation aims to improve the efficiency of the sharing economy by building an agent-based methodological framework for optimal decision-making of distributed agents (e.g., autonomous shared vehicles), including passenger-seeking and route choice. Furthermore, noticing that city planners can impact the behavior of agents via some operational measures such as congestion pricing and signal control, this dissertation investigates the overall bilevel problem that involves the decision-making process of both distributed agents (i.e., the lower level) and central city planners (i.e., the upper level). First of all, for the task of passenger-seeking, this dissertation proposes a model-based Markov decision process (MDP) approach to incorporate distinct features of e-hailing drivers. The modified MDP approach is found to outperform the baseline (i.e., the local hotspot strategy) in terms of both the rate of return and the utilization rate. Although the modified MDP approach is set up in the single-agent setting, we extend its applicability to multi-agent scenarios by a dynamic adjustment strategy of the order matching probability which is able to partially capture the competition among agents. Furthermore, noticing that the reward function is commonly assumed as some prior knowledge, this dissertation unveils the underlying reward function of the overall e-hailing driver population (i.e., 44,000 Didi drivers in Beijing) through an inverse reinforcement learning method, which paves the way for future research on discovering the underlying reward mechanism in a complex and dynamic ride-hailing market. To better incorporate the competition among agents, this dissertation develops a model-free mean-field multi-agent actor-critic algorithm for multi-driver passenger-seeking. A bilevel optimization model is then formulated with the upper level as a reward design mechanism and the lower level as a multi-agent system. We use the developed mean field multi-agent actor-critic algorithm to solve for the optimal passenger-seeking policies of distributed agents in the lower level and Bayesian optimization to solve for the optimal control of upper-level city planners. The bilevel optimization model is applied to a real-world large-scale multi-class taxi driver repositioning task with congestion pricing as the upper-level control. It is disclosed that the derived optimal toll charge can efficiently improve the objective of city planners. With agents knowingwhere to go (i.e., passenger-seeking), this dissertation then applies the bilevel optimization model to the research question of how to get there (i.e., route choice). Different from the task of passenger-seeking where the action space is always fixed-dimensional, the problem of variable action set emerges in the task of route choice. Therefore, a flow-dependent deep Q-learning algorithm is proposed to efficiently derive the optimal policies for multi-commodity multi-class agents. We demonstrate the effect of two countermeasures, namely tolling and signal control, on the behavior of travelers and show that the systematic objective of city planners can be optimized by a proper control.
42

Analysis of microprocessor based vehicular instrumentation and automatic passenger counting systems

Shankar, Sanjeev 12 March 2013 (has links)
Information on transit ridership and operations is a necessary condition as far as efficient management is considered. Transit managements on the acquisition of such a data base can confirm predictions about scheduling, receive warnings about potential dangers and plan future operations on a much broader and precise base. Data from passenger counts provide essential information to marketing and scheduling personnel by identifying peak load-points and the such. Using manual collection methods for such data is expensive and prone to human errors. Automatic Passenger Counting (APC) systems are viewed as an improved and economical technique for data collection. Such systems monitor the progress of a particular vehicle — its position, number of passengers getting on and off, times and distances between stops — and make this data available for processing. These are state of the art systems, mostly microprocessor based and often embracing a modular structure. The Red Pine system is such a system with different dedicated modules for each bank of tasks. Multitasking software is seen to be an powerful tool for such systems and simplify the architecture of the system hardware. A CHMOS hardware design, suited for multitasking softwares is provided. Interfacing software for the Red Pine system has been developed and is explained. Debugging testing and simulation of the Red Pine hardware is detailed. Modifications have been recorded and improvements suggested. / Master of Science
43

Development and implementation of an automatic passenger counter system at a small transit company

Anderson, Paul P. January 1986 (has links)
Automatic Passenger Counter (APC) systems can be very powerful tools for helping transit managers make important decisions about transit operations. Compared to the traditional method of manual data collection, they are a definite improvement. Not only can they collect data tirelessly for days at a time for far less cost, but they also provide very accurate information about the time and distance at which passenger activities occur. This information can be quickly processed into meaningful reports using specially developed software, reducing data turnaround time from months to minutes. This thesis describes the development and installation of an APC system for Valley Metro of Roanoke, Virginia. The research was carried out by the Departments of Civil and Electrical Engineering at Virginia Tech with funding provided by the Virginia Department of Highways and Transportation. The result is an integrated system of equipment, software, and operating techniques which will greatly improve the flow of information at Valley Metro, allowing management the time and resources to do more planning and less paperwork. The work is significant for the following reasons: The software is easy to learn and use and can be run on inexpensive personal computers. The project demonstrates that APC systems are feasible for small transit companies, and that accurate location referencing can be achieved without signposts. The system could be applied at other small transit companies with very little modification required. The following chapters describe the project, including the experiences (both good and bad) and insights gained along the way. / M.S.
44

The economic development impact of passenger transport in the Klipfontein Corridor

Muthien, Ignatius Noel 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: In April 2004, the then Transport MEC of the Western Cape, Tasneem Essop unveiled Government's grand vision of converting Klipfontein Road into a pioneering form of public transport called Bus Rapid Transit (BRT). BRT is the public transport system that the provincial government and City of Cape Town have selected to address South Africa's city transport problems, with a future looking perspective. BRT is characterised by dedicated bus lanes, which will be divided from the normal traffic lanes to ensure that 'express' buses can travel unhindered. Government envisages changing the 20 km Klipfontein Road Corridor stretching from the Inner City through Athlone/Gatesville to Nyanga and Khayelitsha into an activity axis of economic transformation, featuring bus stations, convenience stores, supermarkets, coffee shops and kerbside cafes. This vision of turning Klipfontein Corridor into a well of economic prosperity by using rapid bus transport is primarily what this study will focus on. We are asking whether this goal is attainable and what the positive and negative spin-offs are in respect of sustainable economic growth for the city and a reduction in racially rooted inequalities and inequities. Although a lot of the issues relevant for this study have been raised down the years of the MSDF (1993-1996), current literature on the Klipfontein Corridor is very limited as it is a first for the City of Cape Town and the government. In fact, the national and provincial governments in conjunction with the City of Cape Town have chosen the Klipfontein corridor as a pilot project, with a view to a national roll out in other provinces, if this venture proves successful. / AFRIKAANSE OPSOMMING: In April 2004 het die destydse Minister van Vervoer in die Wes-Kaap, Tasneem Essop onthul dat die regering die groot visie het om Klipfontein weg te transformeer deur gebruik te maak van publieke vervoer bekend as BRT. BRT is die publieke vervoersisteem wat die streeksregering en Kaapstad gekies het, om Suid Afrikaanse stede se vervoerprobleme, met 'n toekoms vooruitsig, op te los. BRT word gekenmerk deur spesiale busbane, apart van die normale verkeer, sodat busse ongehinderd kan voortbeweeg. Die regering beoog om die 20 km Klipfontein korridor te verander in 'n aktiewe node van ekonomiese transformasie met busstasies en winkelkomplekse. Die korridor strek vanaf die Binne Stad deur Athlone/Gatesville na Nyanga en Khayelitsha. Die visie van Me. Tasneem Essop om die Klipfonteinweg te ontwikkel in 'n vooruitstrewende ekonomiese gordel, is die fokus vir die studie. Ons vra of die visie haalbaar is, en wat die positiewe en negatiewe moontlikhede is met betrekking tot langtermyn ekonomiese groei en 'n vermindering in rasse-ongelykhede. Alhoewel baie van die relevante probleme reeds deur die Metropolitaanse Ruimtelike Ontwikkelingsraamwerk (MROR) behandel was, is huidige literatuur oor die Klipfontein projek baie beperk. Tans is dit 'n eerste vir Kaapstad en die regering, wat beoog om soortgelyke projekte uit te rol in ander stede reg oor die land, indien die projek suksesvol is.
45

A study of evaluation methodology for passenger handling facilities insubway stations

Lau, Chung-sum, Edmund., 劉淞森. January 1994 (has links)
published_or_final_version / Transport Studies / Master / Master of Arts
46

Současný systém pražské dopravy a zhodnocení plánů jeho rozvoje / The current system of Prague's traffic and evaluation of its development plans

Rybníček, Jakub January 2010 (has links)
The thesis deals with the problem of current system Prague's traffic and is focused on a public transport and individual automobilism. The main goal of the thesis is to describe and analyse the traffic system in Prague and to define related key problems. It should help to find suitable solutions of described problems. The following target is to evaluate described plans of public transport development. The theoretical part focuses on the general background of road transport, logistics in passenger traffic, dual cycling and also on potential to combine these transport forms. The practical part is then focused on specifics of Prague's traffic system and on plans of its development.
47

Call-back auction mechanism for oversold flights.

January 2012 (has links)
机票超售,即售出的機票多於飛機客艙座位的數量,已經作為“國際慣例“被航空公司廣泛採用。但是这种做法是有争议的,因為其容易導致航班超售,使得旅客被拒登機而滯留,影響航空公司的聲譽。在這篇論文中,我們使用逆向拍賣的機制尋找自願放棄登機資格的旅客以收回部份已預售的低端機票來滿足高端旅客的需求,并同時根據拍賣實現的結果來賠償被拒絶登機旅客。具體地說,我們建立一個二期的機票銷售模型,並且假定低端與高端旅客分別在第一第二個銷售期到來,而航空公司通過決定其在兩個銷售期的銷售策略,使得其利潤最大化。在模型中,航空公司可利用逆向拍賣的方法,要求低端旅客在購買機票的時候,提交一個其在因為航班超售時,自願放棄座位的赔偿要求。當航班超售時,航空公司可根據低端旅客的競投信息,從中挑選出價最低的旅客,通過滿足他們的賠償要求,收回他們的機票以滿足高端旅客的需求。我们发现我们的机制在大多数情况下,可以提高航空公司的利润,改善航班的登機效率,同时,也能滿足部份低端旅客通過改變計劃行程獲取賠償的需求。我們也會比較逆向拍賣機制與其他現有機制,例如固定價格補償機制。此外,我們也會就逆向拍賣機票銷售模型中的定價问题进行研究。 / With increasing applications of revenue management, airline companies often oversell their tickets. This practice is controversial because some passengers would not be able to board when the number of show-up customers exceeds the available seats. And this might make the affected customers upset and thus affect the future revenue of the airline. In this paper, we propose a new mechanism - a call-back auction, in which the passengers are asked to submit a bid to indicate the compensation they would like to receive for giving up their seats and changing their original flight schedule. This could provide the airline with information to select passengers with the lowest compensation requirements and also reduce the negative impact on customer relationship. We develop a model with booking limit decision and examine the impact of this call-back auction mechanism on the airline's profitability and compare it with other existing mechanisms such as fixed-price compensation. We find that our mechanism can lead to higher profit for the airlines in most cases. In this study, pricing issues are also examined. / Detailed summary in vernacular field only. / Zhong, Zhiheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 72-76). / Abstracts also in Chinese. / Table of Contents --- p.vii / Chapter 0 --- Notation / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Literature Review --- p.7 / Chapter 3 --- Call-back Auction --- p.13 / Chapter 3.1 --- The Concept --- p.13 / Chapter 3.2 --- Implementation --- p.14 / Chapter 4 --- A Two-Period Model with Call-back Auction --- p.19 / Chapter 4.1 --- Uniform Price Call-back Auction --- p.21 / Chapter 4.2 --- Numerical Examples --- p.27 / Chapter 4.3 --- First-price Call-back Auction --- p.35 / Chapter 4.4 --- Revenue Comparison --- p.39 / Chapter 4.5 --- Call-back Auction with Reserve Compensation --- p.41 / Chapter 4.6 --- Alternative Information Structure --- p.50 / Chapter 5 --- Endogenous High-fare Price --- p.59 / Chapter 5.1 --- Additive Demand Function --- p.60 / Chapter 6 --- Conclusion --- p.68 / Bibliography --- p.72
48

Legal aspects of facilitation in civil aviation : health issues

Poget, Gaël January 2003 (has links)
No description available.
49

Passenger safety of public transport systems in Hong Kong

Yip, Chi-ching, Alexis., 葉智靑. January 2003 (has links)
published_or_final_version / Transport Policy and Planning / Master / Master of Arts in Transport Policy and Planning
50

A study of the impact of SARS on air transport demand in Hong Kong: the case of Cathay Pacific Airways

Ng, Wai-leung, Weland., 伍偉良. January 2004 (has links)
published_or_final_version / abstract / toc / Transport Policy and Planning / Master / Master of Arts in Transport Policy and Planning

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