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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.
131

An improved tabu search for airport gate assignment.

January 2009 (has links)
Kwan, Cheuk Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (p. 115-118). / Abstract also in Chinese. / Chapter 1 --- Introduction --- p.9 / Chapter 1.1 --- The Gate Assignment Problem --- p.9 / Chapter 1.2 --- Contributions --- p.10 / Chapter 1.3 --- Formulation of Gate Assignment Problem --- p.11 / Chapter 1.4 --- Organization of Thesis --- p.13 / Chapter 2 --- Literature Review --- p.15 / Chapter 2.1 --- Introduction --- p.15 / Chapter 2.2 --- Formulations of Gate Assignment Problems --- p.15 / Chapter 2.2.1 --- Static Gate Assignment Model --- p.16 / Chapter 2.2.1.1 --- Total Passenger Walking Distance --- p.17 / Chapter 2.2.1.2 --- Waiting Time --- p.20 / Chapter 2.2.1.3 --- Unassigned Flights --- p.21 / Chapter 2.2.2 --- Stochastic and Robust Gate Assignment Model --- p.22 / Chapter 2.2.2.1 --- Idle Time --- p.22 / Chapter 2.2.2.2 --- Buffer Time --- p.23 / Chapter 2.2.2.3 --- Flight Delays --- p.23 / Chapter 2.2.2.4 --- Gate Conflicts --- p.24 / Chapter 2.3 --- Solution Methodologies --- p.25 / Chapter 2.3.1 --- Expert System Approaches --- p.25 / Chapter 2.3.2 --- Optimization --- p.27 / Chapter 2.3.2.1 --- Exact Methods --- p.27 / Chapter 2.3.2.2 --- Heuristic Approaches --- p.28 / Chapter 2.3.2.3 --- Meta-Heuristics Approaches --- p.29 / Chapter 2.3.2.4 --- Tabu Search and Path Relinking --- p.31 / Chapter 2.4 --- Current Practice of Gate Assignment Problems --- p.32 / Chapter 2.5 --- Summary --- p.32 / Chapter 3 --- Tabu Search --- p.34 / Chapter 3.1 --- Introduction --- p.34 / Chapter 3.2 --- Mathematical Model --- p.34 / Chapter 3.3 --- Principles of Tabu Search --- p.36 / Chapter 3.4 --- Neighborhood Structures --- p.38 / Chapter 3.4.1 --- Insert Move --- p.38 / Chapter 3.4.2 --- Exchange Move --- p.39 / Chapter 3.5 --- Short Term Memory Structure --- p.41 / Chapter 3.6 --- Aspiration Criterion --- p.42 / Chapter 3.7 --- Intensification and Diversification Strategies --- p.43 / Chapter 3.8 --- Tabu Search Framework --- p.45 / Chapter 3.8.1 --- Initial Solution --- p.45 / Chapter 3.8.2 --- Tabu Search Algorithm --- p.46 / Chapter 3.9 --- Computational Studies --- p.52 / Chapter 3.9.1 --- Parameters Tuning --- p.52 / Chapter 3.9.1.1 --- Fine-tuning a Tabu Search Algorithm with Statistical Tests --- p.53 / Chapter 3.9.1.2 --- Tabu Tenure --- p.54 / Chapter 3.9.1.3 --- Move Selection Strategies --- p.56 / Chapter 3.9.1.4 --- Frequency of Exchange Moves --- p.59 / Chapter 3.9.2 --- Comparison the Fine-tuned TS with original TS --- p.62 / Chapter 3.10 --- Conclusions --- p.63 / Chapter 4 --- Path Relinking --- p.65 / Chapter 4.1 --- Introduction --- p.65 / Chapter 4.2 --- Principles of Path Relinking --- p.65 / Chapter 4.2.1 --- Example of Path Relinking --- p.66 / Chapter 4.3 --- Reference Set --- p.68 / Chapter 4.3.1 --- Two-Reference-Set Implementation --- p.71 / Chapter 4.3.1.1 --- Random Exchange Gate Move --- p.72 / Chapter 4.4 --- Initial and Guiding Solution --- p.73 / Chapter 4.5 --- Path-Building Process --- p.74 / Chapter 4.6 --- Tabu Search Framework with Path Relinking --- p.78 / Chapter 4.6.1 --- Computational Complexities --- p.82 / Chapter 4.7 --- Computational Studies --- p.82 / Chapter 4.7.1 --- Best Configuration for Path Relinking --- p.83 / Chapter 4.7.1.1 --- Reference Set Strategies and Initial and Guiding Criteria --- p.83 / Chapter 4.7.1.2 --- Frequency of Path Relinking --- p.86 / Chapter 4.7.1.3 --- Size of Volatile Reference Set --- p.87 / Chapter 4.7.1.4 --- Size of Non-volatile Reference Set --- p.89 / Chapter 4.7.2 --- Comparisons with Other Algorithms --- p.94 / Chapter 5 --- Case Study --- p.98 / Chapter 5.1 --- Introduction --- p.98 / Chapter 5.2 --- Airport Background --- p.98 / Chapter 5.2.1 --- Layout of ICN --- p.98 / Chapter 5.3 --- Data Preparation --- p.99 / Chapter 5.3.1 --- Passenger Data --- p.103 / Chapter 5.4 --- Computational Studies --- p.104 / Chapter 5.4.1 --- Experiments without Airline Preference --- p.104 / Chapter 5.4.2 --- Experiments with Airline Preference --- p.106 / Chapter 5.4.2.1 --- Formulation --- p.106 / Chapter 5.4.2.2 --- Results --- p.108 / Chapter 5.5 --- Conclusion --- p.111 / Chapter 6 --- Conclusion --- p.112 / Chapter 6.1 --- Summary of Achievement --- p.112 / Chapter 6.2 --- Future Developments --- p.113 / Bibliography --- p.115 / Appendix --- p.119 / Chapter 1. --- Friedman´ةs Test --- p.119 / Chapter 2. --- Wilcoxon's Signed Rank Test for Paired Observation --- p.120 / Chapter 3. --- Hybrid Simulated Annealing with Tabu Search Approach --- p.121 / Chapter 4. --- Arrival Flight Data of Incheon International Airport --- p.122 / Chapter 5. --- Departure Flight Data of Incheon International Airport --- p.139
132

Metroplex identification, evaluation, and optimization

McClain, Evan James 08 April 2013 (has links)
As airspace congestion becomes increasingly more common, one of the primary places airspace congestion is felt today, and will only continue to increase, is in areas where more than one major airport interact. We will call these groups of interdependent airports a metroplex; a term originally coined to describe large metropolitan areas where more than one city of equal (or near equal) size or importance. These metroplex areas are of particular importance in understanding future capacity demands because many of these areas are currently experiencing problems with meeting the current demand, and demand is only projected to increase as air travel becomes more popular. Many of these capacity issues have been identified in the FAA's Future Airport Capacity Task (FACT). From the second FACT report, it is stated that "the FACT 1 analysis revealed that many of our hub airports and their associated metropolitan areas could be expected to experience capacity constraints (i.e. unacceptable levels of delay) by 2013 and 2020, even if the planned improvements envisioned at that time were completed." This analysis shows that the current methods of expanding airports will not scale with the growing demand. To address this growing demand, a three part solution is proposed. The first step is to properly identify the metroplex areas to be evaluated. While the FACT reports serve to identify areas where capacity growth does not meet demand, these areas are not grouped into metroplexes. To do this grouping, an interaction metric was developed based on airport distance and traffic volume. This interaction metric serves as a proxy for how the existence of a second airport impacts the operation of the first. This pairwise metric was then computed for all commercial airports in the US and were grouped into metroplexes using a clustering algorithm. The second obstacle was to develop a tool to evaluate each metroplex as new algorithms were tested. A discrete event based simulation was developed to model each link in the airspace structure for each aircraft that enters the TRACON. This program tracks the delay each aircraft is required to accumulate in holding patterns or traffic trombones. A third and final method discussed here was an optimization program that can be used to schedule aircraft that are entering the TRACON to perform small modifications in their speed while en route to reduce the overall delay (both en route and in the TRACON). While formal optimization methods for scheduling aircraft arrivals have been presented before, the computational complexity has greatly prevented such algorithms from being used to schedule many aircraft in a dense schedule. This is because mixed integer programming (MIP) is a NP-hard problem. Practically, this means that the solution time can grow exponentially as the problem size (number of aircraft) increases. To address this issue, a Benders' decomposition scheme was introduced that allows solutions to be computed in near real-time on commodity hardware. These solutions can be evaluated and compared against the currently used TMA algorithm to show surprising gains in high density traffic.
133

A Risk-Based Optimization Framework for Security Systems Upgrades at Airports

Berbash, Khaled January 2010 (has links)
Airports are fast-growing dynamic infrastructure assets. For example, the Canadian airport industry is growing by 5% annually and generates about $8 billion yearly. Since the 9/11 tragedy, airport security has been of paramount importance both in Canada and worldwide. Consequently, in 2002, in the wake of the attacks, the International Civil Aviation Organization (ICAO) put into force revised aviation security standards and recommended practices, and began a Universal Security Audit Program (USAP), in order to insure the worldwide safeguarding of civil aviation in general, and of airports in particular, against unlawful interference. To improve aviation security at both the national level and for individual airport, airport authorities in North America have initiated extensive programs to help quantify, detect, deter, and mitigate security risk. At the research level, a number of studies have examined scenarios involving threats to airports, the factors that contribute to airport vulnerability, and decision support systems for security management. However, more work is still required in the area of developing decision support tools that can assist airport officials in meeting the challenges associated with decision about upgrades; determining the status of their security systems and efficiently allocating financial resources to improve them to the level required. To help airport authorities make cost-effective decisions about airport security upgrades, this research has developed a risk-based optimization framework. The framework assists airport officials in quantitatively assessing the status of threats to their airports, the vulnerability to their security systems, and the consequences of security breaches. A key element of this framework is a new quantitative security metric ; the aim of which is to assist airport authorities self-assess the condition of their security systems, and to produce security risk indices that decision makers can use as prioritizing criteria and constraints when meeting decisions about security upgrades. These indices have been utilized to formulate an automated decision support system for upgrading security systems in airports. Because they represent one of the most important security systems in an airport, the research focuses on passenger and cabin baggage screening systems. Based on an analysis of the related threats, vulnerabilities and consequences throughout the flow of passengers, cabin baggage, and checked-in luggage, the proposed framework incorporates an optimization model for determining the most cost-effective countermeasures that can minimize security risks. For this purpose, the framework first calculates the level of possible improvement in security using a new risk metric. Among the important features of the framework is the fact that it allows airport officials to perform multiple “what-if” scenarios, to consider the limitations of security upgrade budgets, and to incorporate airport-specific requirements. Based on the received positive feedback from two actual airports, the framework can be extended to include other facets of security in airports, and to form a comprehensive asset management system for upgrading security at both single and multiple airports. From a broader perspective, this research contributes to the improvement of security in a major transportation sector that has an enormous impact on economic growth and on the welfare of regional, national and international societies.
134

A Risk-Based Optimization Framework for Security Systems Upgrades at Airports

Berbash, Khaled January 2010 (has links)
Airports are fast-growing dynamic infrastructure assets. For example, the Canadian airport industry is growing by 5% annually and generates about $8 billion yearly. Since the 9/11 tragedy, airport security has been of paramount importance both in Canada and worldwide. Consequently, in 2002, in the wake of the attacks, the International Civil Aviation Organization (ICAO) put into force revised aviation security standards and recommended practices, and began a Universal Security Audit Program (USAP), in order to insure the worldwide safeguarding of civil aviation in general, and of airports in particular, against unlawful interference. To improve aviation security at both the national level and for individual airport, airport authorities in North America have initiated extensive programs to help quantify, detect, deter, and mitigate security risk. At the research level, a number of studies have examined scenarios involving threats to airports, the factors that contribute to airport vulnerability, and decision support systems for security management. However, more work is still required in the area of developing decision support tools that can assist airport officials in meeting the challenges associated with decision about upgrades; determining the status of their security systems and efficiently allocating financial resources to improve them to the level required. To help airport authorities make cost-effective decisions about airport security upgrades, this research has developed a risk-based optimization framework. The framework assists airport officials in quantitatively assessing the status of threats to their airports, the vulnerability to their security systems, and the consequences of security breaches. A key element of this framework is a new quantitative security metric ; the aim of which is to assist airport authorities self-assess the condition of their security systems, and to produce security risk indices that decision makers can use as prioritizing criteria and constraints when meeting decisions about security upgrades. These indices have been utilized to formulate an automated decision support system for upgrading security systems in airports. Because they represent one of the most important security systems in an airport, the research focuses on passenger and cabin baggage screening systems. Based on an analysis of the related threats, vulnerabilities and consequences throughout the flow of passengers, cabin baggage, and checked-in luggage, the proposed framework incorporates an optimization model for determining the most cost-effective countermeasures that can minimize security risks. For this purpose, the framework first calculates the level of possible improvement in security using a new risk metric. Among the important features of the framework is the fact that it allows airport officials to perform multiple “what-if” scenarios, to consider the limitations of security upgrade budgets, and to incorporate airport-specific requirements. Based on the received positive feedback from two actual airports, the framework can be extended to include other facets of security in airports, and to form a comprehensive asset management system for upgrading security at both single and multiple airports. From a broader perspective, this research contributes to the improvement of security in a major transportation sector that has an enormous impact on economic growth and on the welfare of regional, national and international societies.
135

The performance measurement of the Taiwan¡¦s terminals¡Gan application of Three-Stage SBM-DEA

Hsueh, Kuang-lin 08 September 2008 (has links)
For a long time ,the whole performance of the Taiwan¡¦s terminals that present both the passengers and the aircraft movements decline tendency.This research was from 2003 to 2007 the Taiwan¡¦s top 10 terminals as the object of study. The aim of study was providing the government and managers understood the implying of performance. This study based on Avkiran & Rowands (2008) Three-Stage SBM-DEA for the main methodology that excluded both external factor and statistic interference. And applied auxiliary by Malmquist index, carried on the performance measurement of the Taiwan¡¦s top 10 terminals with more detached and more impartial. According to the analysis it provided the government and managers to improve and work out a better future.
136

Metropolitan park at Kai Tak : a feeling of 'urban excitement' within a 'urban resort' /

Lam, Kai-mei, Frances. January 1999 (has links)
Thesis (M.L.A.)--University of Hong Kong, 1999. / Includes special study report entitled: The use of tensile fabric in landscape architecture. Includes bibliographical references.
137

Crews facilities complex for Cathay Pacific Airways at Chek Lap Kok Airport /

Leung, Pik-ying, Blanche. January 1995 (has links)
Thesis (M. Arch.)--University of Hong Kong, 1995. / Includes special study report entitled: Movement analysis with respect to site circulation & interior circulation. Includes bibliographical references.
138

Using boredom proneness to predict vigilance in airport security luggage screening

Linnabery, Eileen Marie. January 2009 (has links)
Thesis (M.A.)--University of West Florida, 2009. / Submitted to the Dept. of Psychology. Title from title page of source document. Document formatted into pages; contains 69 pages. Includes bibliographical references.
139

Aéroports : quelques enjeux juridiques actuels

Hartmann, Cyril. January 2005 (has links)
The following thesis deals with three current legal issues regarding airports. / In the first chapter the development of airport ownership and management structures will be studied. Although in most cases airports are still owned and managed by governments or local bodies, since the 1960s, new approaches to ownership and management have come into practise. This phenomenon is studied from the perspective of its impact upon public air law. / The second chapter deals with airport charges and their international legal framework. After examining the different forms of airport charges and the recommendations enacted by the International Civil Aviation Organization (ICAO), the author will be led to the conclusion that the current legal regime is unsatisfactory and that the most appropriate solution to this would be to incorporate the principles formulated by ICAO in an Annex to the Chicago Convention. / The third and final chapter is devoted to the study of a legal dispute between Switzerland and Germany with respect to the approach paths to Zurich airport through German airspace. It is concluded that the unilateral legal measures taken by the German government are, with one exception, in conformity with international law.
140

Airline Passengers' Satisfaction with Airports

Kim, Hyun Joo 2011 December 1900 (has links)
Airports are places where people have the potential to experience either satisfaction or frustration, and marketing and tourism scholars have argued that customer satisfaction is one of the primary goals of airports. However, few studies have systemically analyzed the service quality and efficiency of airports, or examined customer satisfaction with airport facilities. While airline passengers' expectations of airport service quality have been examined, there are few studies focusing on both their expectations and desires regarding airport services. Furthermore, to the best of our knowledge, no available studies have analyzed passengers' expectations and desires on the basis of the desires congruency model. This study attempted to define tourists' desires and expectations congruency as well as their satisfaction with their entire airport experiences. A total of 262 airline passengers in Incheon International Airport and Los Angeles International Airport participated in the study. Six hypotheses were tested with data collected from a survey of the airline passengers with the use of descriptive statistics and structural equation modeling. Most relationships among latent variables were found to be in accordance with previous studies. Furthermore, the results of the current study implied that the desires congruency model could be applied to the satisfaction formation of airline passengers. Practical recommendations are presented for the airport managers to enhance airport services.

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