This dissertation details an algorithm to solve the Intratheater Airlift Operations Problem (IAOP) using advanced tabu search. A solution to the IAOP determines the routes and assignment of customer requests to a fleet of aircraft over a given time horizon. This problem and other variants comprise an ongoing challenge for United States Air Force (USAF) planners who manage detailed logistics throughout many theaters of operations. Attributes of the IAOP include cargo time windows, multiple cargo types, multiple vehicle cargo bay configurations, vehicle capacity, route duration limits, and port capacities. The IAOP multi-criteria objective embraces several components with the primary goal of satisfying as much of the demand as possible while minimizing cost. The algorithm is extended to allow split load deliveries of customer requests, allowing a shipment to be split into two or more sub-loads which are delivered separately to the customer. The split load relaxation, while significantly increasing the complexity of the problem, allows for possible improvement in the solution. The necessary changes to the model and algorithm are detailed, providing a foundation to extend any local search algorithm solving a vehicle routing problem to allow split loading. Results allowing split loading are presented and compared with results without split loading. The algorithm is also extended to include a rolling time horizon. Starting from a solution found at a previous time step, the algorithm is limited on how the solution can be modified. This reflects the reality of operations in which near-term plans are locked as they approach and enter execution while longer-term plans are continually updated as new information arrives. / text

The research reported in this thesis considers the classical combinatorial optimization problem known as the Generalized Assignment Problem (GAP). Since the mid 1970's researchers have been developing solution approaches for this particular type of problem due to its importance both in practical and theoretical terms. Early attempts at solving GAP tended to use exact integer programming techniques such as Branch and Bound. Although these tended to be reasonably successful on small problem instances they struggle to cope with the increase in computational effort required to solve larger instances. The increase in available computing power during the 1980's and 1990's coincided with the development of some highly efficient heuristic approaches such as Tabu Search (TS), Genetic Algorithms (GA) and Simulated Annealing (SA). Heuristic approaches were subsequently developed that were able to obtain high quality solutions to larger and more complex instances of GAP. Most of these heuristic approaches were able to outperform highly sophisticated commercial mathematical programming software since the heuristics tend to be tailored to the problem and therefore exploit its structure. A new approach for solving GAP has been developed during this research that combines the exact Branch and Bound approach and the heuristic strategy of Tabu Search to produce a hybrid algorithm for solving GAP. This approach utilizes the mathematical programming software Xpress-MP as a Branch and Bound solver in order to solve sub-problems that are generated by the Tabu Search guiding heuristic. Tabu Search makes use of memory structures that record information about attributes of solutions visited during the search. This information is used to guide the search and in the case of the hybrid algorithm to generate sub problems to pass to the Branch and Bound solver. The new algorithm has been developed, imp lemented and tested on benchmark test problems that are extremely challenging and a comprehensive report and analysis of the experimentation is reported in this thesis.

During an emergency evacuation, most people will use their vehicles to evacuate. However, there is a group of people who do not have access to reliable transportation or for some reason cannot drive, even if they have their own automobiles - the carless. There are different groups of carless (disabled, medically homebound, poor or immigrant populations, etc.) who require different forms of transportation assistance during an emergency evacuation. In this study we focus on those carless who are physically intact and able to walk to a set of designated locations for transportation during an emergency, and we propose using public transit and school buses to evacuate this carless group. A model has been developed to accommodate the use of public transit and school buses to efficiently and effectively evacuate the carless. The model has two parts. Part 1 is a location problem which aims at congregating the carless at some specific locations called evacuation sites inside the affected area. To achieve this goal, the affected area is partitioned into zones and this congregating of the carless has been formulated as a Single Source Capacitated Facility Location Problem. Changes in the demand of the carless in zones over different periods of a day and over different days of the week have been considered and included in the model. A walking time constraint is explicitly considered in the model. A heuristic developed by Klincewicz and Luss (1986) has been used to solve this location model.Part 2 is a routing problem which aims at obtaining itineraries of buses to pick up the carless at evacuation sites and transport them to safe locations outside the affected area, such that the total number of carless evacuated with the given time limit is maximized. A Tabu search heuristic has been developed for solving the routing problem. Computational results show that the Tabu search heuristic efficiently and effectively solves the routing problem; in particular, the initial heuristic produces a high quality initial solution in very short time. This study has also made slight contribution to the development of the Tabu search technique.

In the last two decades, the western world witnessed a continuous rise in the health expenditure. Meanwhile, complaints from patients on excessive waiting times are also increasing. In the past, many researchers have tried to devise appointment scheduling rules to provide trade-offs between maximizing patients’ satisfaction and minimizing the costs of the health providers. For instance, this challenge appears appointment scheduling problems (ASP). Commonly used methods in ASP include analytical methods, simulation studies, and combination of simulation with heuristic approaches. Analytical methods (e.g., queuing theory and mathematical programming) face challenges of fully capturing the complexities of systems and usually make strong assumptions for tractability of problems. These methods simplify the whole system to a single-stage unit and ignore the actual system factors such as the presence of multiple stages and/or resource constraints. Simulation studies, conversely, are able to model most complexities of the actual system, but they typically lack an optimization strategy to deliver optimal appointment schedules. Also, heuristic approaches normally are based on intuitive rules and do not perform well as standalone methods. In order to reach an optimal schedule while considering complexities in actual health care systems, this thesis proposes efficient and effective methods that yield (near) optimal appointment schedules by integrating mathematical programming, a tabu search optimization algorithm and discrete event simulation. The proposed methodologies address the challenges and complexities of scheduling in real world multistage healthcare units in the presence of stochastic service durations, a mix of patient types, patients with heterogeneous service sequence, and resource constraints. Moreover, the proposed methodology is capable of finding the optimum considering simultaneously multiple performance criteria. A Pareto front (a set of optimal solutions) for the performance criteria can be obtained using the proposed methods. Healthcare management can use the Pareto front to choose the appropriate policy based on different conditions and priorities. In addition, the proposed method has been applied to two case studies of Operating Rooms departments in two major Canadian hospitals. The comparison of actual schedules and the ones yielded by the proposed method indicates that proposed method can improve the appointment scheduling in realistic clinical settings.

In the last two decades, the western world witnessed a continuous rise in the health expenditure. Meanwhile, complaints from patients on excessive waiting times are also increasing. In the past, many researchers have tried to devise appointment scheduling rules to provide trade-offs between maximizing patients’ satisfaction and minimizing the costs of the health providers. For instance, this challenge appears appointment scheduling problems (ASP). Commonly used methods in ASP include analytical methods, simulation studies, and combination of simulation with heuristic approaches. Analytical methods (e.g., queuing theory and mathematical programming) face challenges of fully capturing the complexities of systems and usually make strong assumptions for tractability of problems. These methods simplify the whole system to a single-stage unit and ignore the actual system factors such as the presence of multiple stages and/or resource constraints. Simulation studies, conversely, are able to model most complexities of the actual system, but they typically lack an optimization strategy to deliver optimal appointment schedules. Also, heuristic approaches normally are based on intuitive rules and do not perform well as standalone methods. In order to reach an optimal schedule while considering complexities in actual health care systems, this thesis proposes efficient and effective methods that yield (near) optimal appointment schedules by integrating mathematical programming, a tabu search optimization algorithm and discrete event simulation. The proposed methodologies address the challenges and complexities of scheduling in real world multistage healthcare units in the presence of stochastic service durations, a mix of patient types, patients with heterogeneous service sequence, and resource constraints. Moreover, the proposed methodology is capable of finding the optimum considering simultaneously multiple performance criteria. A Pareto front (a set of optimal solutions) for the performance criteria can be obtained using the proposed methods. Healthcare management can use the Pareto front to choose the appropriate policy based on different conditions and priorities. In addition, the proposed method has been applied to two case studies of Operating Rooms departments in two major Canadian hospitals. The comparison of actual schedules and the ones yielded by the proposed method indicates that proposed method can improve the appointment scheduling in realistic clinical settings.

There is an increasing interest in sustainability and a growing debate about environmental policy measures aiming at the reduction of green house gas emissions across di erent economic sectors worldwide. The transportation sector is one major greenhouse gas emitter which is heavily regulated to reduce its dependance on oil. These regulations along with the growing customer awareness about global warming has led vehicle manufacturers to seek di erent technologies to improve vehicle e ciencies and reduce the green house gases emissions while at the same time meeting customer's expectation of mobility and exibility. Plug-in hybrid electric vehicles (PHEV) is one major promising solution for a smooth transition from oil dependent transportation sector to a clean electric based sector while not compromising the mobility and exibility of the drivers. In the medium term, plug-in hybrid electric vehicles (PHEV) can lead to signi cant reductions in transportation emissions. These vehicles are equipped with a larger battery than regular hybrid electric vehicles which can be recharged from the grid. For short trips, the PHEV can depend solely on the electric engine while for longer journeys the alternative fuel can assist the electric engine to achieve extended ranges. This is bene cial when the use pattern is mixed such that and short long distances needs to be covered. The plug-in hybrid electric vehicles are well-suited for logistics since they can avoid the possible disruption caused by charge depletion in case of all-electric vehicles with tight time schedules. The use of electricity and fuel gives rise to a new variant of the classical vehicle routing with time windows which we call the plug-in hybrid electric vehicle routing problem with time windows (PHEVRPTW). The objective of the PHEVRPTW is to minimize the routing costs of a eet of PHEVs by minimizing the time they run on gasoline while meeting the demand during the available time windows. As a result, the driver of the PHEV has two decisions to make at each node: (1) recharge the vehicle battery to achieve a longer range using electricity, or (2) continue to the next open time window with the option of using the alternative fuel. In this thesis, we present a mathematical formulation for the plug-in hybrid-electric vehicle routing problem with time windows. We solve this problem using a Lagrangian relaxation and we propose a new tabu search algorithm. We also present the rst results for the full adapted Solomon instances.

Diplomarbeit Hochschule für Angewandte Psychologie Zürich, 2005.

Made available in DSpace on 2014-06-11T19:30:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-20Bitstream added on 2014-06-13T20:21:17Z : No. of bitstreams: 1 cossi_am_dr_ilha.pdf: 1798466 bytes, checksum: 3b0c96085dcf5e4f3e999327f4a5b0f4 (MD5) / Fundação de Ensino Pesquisa e Extensão de Ilha Solteira (FEPISA) / Neste trabalho apresentam-se os conceitos teóricos, modelos matemáticos, técnicas de solução e resultados de pesquisas desenvolvidas envolvendo o planejamento de redes de distribuição de energia elétrica de MT e planejamento e projeto de circuitos secundários de BT. O problema de planejamento de redes de MT e planejamento e projetos de circuitos de BT, é abordado através de uma modelagem completa e as propostas de solução são através de “meta heurísticas” mono e multi-objetivos. As restrições consideradas nestes modelos referem-se à radialidade dos sistemas planejados, suprimento da demanda nas barras de consumo em cada estágio do programa de planejamento, limites máximos de queda de tensão permitidos nos alimentadores restrições físicas de operação de equipamentos, condutores e restrições de natureza financeira. O modelo de planejamento de redes de MT é abordado como um problema de programação não linear inteiro misto (PNLIM) multi-objetivo. Os objetivos referem-se aos custos de investimentos e de confiabilidade da rede. Para solução do problema utiliza-se um algoritmo Tabu Search (TS) reativo em que os múltiplos objetivos são considerados através dos conceitos de fronteira ótima de Pareto. Para avaliar as propostas de soluções é utilizado como ferramenta auxiliar um algoritmo de fluxo de potência monofásico. No modelo que trata do problema de planejamento e projetos de circuitos secundários, são considerados tanto ações de planejamentos como de projetos. Para tal é proposta uma metodologia em três etapas seqüenciais: a primeira refere-se ao balanceamento de cargas nas fases abc do circuito, a segunda à localização (Geralmente no centro de cargas), capacidade e quantidade de transformadores abaixadores na rede e a terceira define as rotas e o tipo de cabo dos alimentadores secundários. O modelo é formulado como um problema... / This work presents the theory, the mathematical model, the solution techniques and the results of the developed research dealing with MV (medium voltage) electrical energy distribution network planning and the secondary circuit project of LV (low voltage). The problem of planning MV networks and planning and project LV circuits is approached by a complete modeling and the solution proposals are effectuated by mono and multi objective meta heuristics. The restrictions considered in these models are referred to the radial form of the planned systems, demand supplying on the busses in each stage of the planning program, maximum limits of voltage drops allowed on the feeders, physical restrictions of operation on the equipments and financial restrictions. The planning model of MV network is approached as a multi objective nonlinear integer mist programming problem (NLIMPP). The objectives are referred to the investment costs, and reliability costs. To solve the problem a reactive Tabu Search (TS) algorithm is used where the multiple objectives are considered by the optimal frontier Pareto concept. To evaluate the solution proposals a monophasic power flow algorithm is used as an auxiliary tool. The secondary circuit planning and project models consider as much as planning and project actions. For this a three stage methodology is proposed: the first is referred to load balancing on abc phases of the circuit; the second to the location (generally on the load center) capacity and quantity of lower transformers on the network, and the third defines the directions and the type of the secondary feeders. The model is formulated as a nonlinear integer mist programming problem (NLIMPP), and for the solution is proposed a TS algorithm. To evaluate the solution proposals a three phase power flow with four conductors (three phases and one neutral) is used as an auxiliary algorithm. The integrated... (Complete abstract click electronic access below)

Made available in DSpace on 2016-08-03T16:34:37Z (GMT). No. of bitstreams: 1 ROSANE SILVA DE OLIVEIRA.pdf: 257435 bytes, checksum: 930f04b8209408beaa0c5e2e0f8c213a (MD5) Previous issue date: 2006-10-27 / The central theme of this thesis addresses the practices of hospital psychologists and chaplains in loss by death situations. The thesis purpose is to understand the processes of receiving, caring for and advising carried out by psychologists and chaplains in situations of death; and investigating the similarities and differences between these professionals in their methods of receiving, caring for, and advising in situations of loss by death. The research subjects included 1 Protestant Chaplain, 1 Chaplain Priest of St. Camillo, and 2 psychologists, all of whom work with pastoral care and psychological assistance in hospitals. The qualitative method of investigation used in this research is the Grounded Theory (PIRES 2001) whose data categorization and interpretation considers all verbal content, respecting each word spoken by the subject. The chaplain was interviewed in her office at the university where she works and the other subjects were interviewed in the hospital itself, on which occasion we asked them to speak about their working methods in the hospital setting. Through the results obtained it was possible to verify that there still today is difficulty in dealing with the term death and in defining the concept of death, both in the religious and psychological realm. There is a very strong culture, which surrounds human relations and makes our understanding more difficult, impeding us from mentioning the word death. It was possible to identify divergences in the daily practices of both chaplains and psychologists with respect to the Methods and Techniques, as these become confused at moment of receiving, advising, and giving support to persons that are confronting loss by death. Both chaplains and psychologists said that spirituality is a resource used to confront this loss by death and the suggestions and feelings of those interviewed in relation to their practices was that the professionals need space of expression in order for the their work to become fully integrated, need to provide support to the caregivers, and need to demystify the chaplain s work and the need for the work of the psychologists to be extended to hospital employees. We concluded that through the research carried out there is confusion in the roles or functions between the Chaplain and Psychologist. This confusion puts into question the very professional, role, or techniques of intervention. This suggests that there is a need in the education of these professionals for clarification of information regarding their role when faced with loss by death. / Este trabalho traz como tema central às práticas de capelães e psicólogos hospitalares junto às pessoas em situação de perda por morte. Os objetivos desse trabalho foi compreender os processos de acolhimento, cuidado e aconselhamento que são realizados por psicólogos e capelães nas situações de luto; e investigar as semelhanças e diferenças nas práticas de acolhimento, cuidado e aconselhamento entre esses profissionais nas situações de luto por morte. Foram sujeitos desta pesquisa 1 Capelã protestante, 1 Capelão Padre Camiliano, e 2 Psicólogas, que trabalhavam com acolhimento, cuidado, aconselhamento pastoral e psicológico em hospitais. O método de investigação qualitativo utilizado nesta pesquisa foi a Grounded Teory , que categoriza dados e cuja interpretação é realizada considerando todo o conteúdo verbal, respeitando-se cada palavra dada pelo sujeito. A Capelã foi entrevistada em sua sala de atendimento na universidade onde trabalha e os demais sujeitos foram entrevistados nas próprias dependências dos hospitais, ocasião em que solicitamos que falassem sobre suas práticas de trabalho no contexto hospitalar. Pelos resultados obtidos foi possível verificar que existe ainda hoje uma dificuldade para lidar com o termo morte e para definir o conceito de morte, tanto no âmbito religioso, como no psicológico. Existe uma cultura muito forte, que cerca as relações humanas e que dificulta a nossa compreensão e que nos impede de mencionar a palavra morte. Foi possível identificar divergências na prática diária tanto dos capelães, quanto das psicólogas, em relação aos seus Métodos e Técnicas, pois eles se confundem na hora do acolhimento, do aconselhamento, do apoio dado às pessoas que estão passando pela perda por morte. Tanto os capelães, como as psicólogas disseram que a espiritualidade é um recurso utilizado para o enfrentamento dessa perda por morte e as sugestões e sentimentos dos entrevistados em relação as suas práticas foram que os profissionais necessitam de um espaço de expressão, para o desenvolvimento de um trabalho integrado, para um suporte aos cuidadores, para a necessidade de se desmistificar o trabalho do capelão e da necessidade do trabalho das psicólogas se estender aos funcionários do hospital. Concluímos que através da pesquisa realizada apresenta-se confusão nos papéis ou funções entre Capelão e Psicólogo. Esta confusão coloca em dúvida a própria profissão, atuação ou técnicas de intervenção. Isto sugere que há necessidade, na formação destes profissionais, de esclarecimentos ou conhecimentos sobre sua atuação diante da perda por morte

The aim of this thesis is to analyze the topics of crime, violence and brutality in four novels written by a contemporary British novelist Ian McEwan. The aim of the thesis is also to define the motivational development of these topics and moral questions of guilt and punishment based on the analysis of Ian McEwan's novel Solar. The goal is to reflect problems of the society of the 21st century including the basic moral questions connected with the professional life and career of McEwan's characters.