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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.
91

Study on the Operation management of a Branch ofice of Taipei Post Office after Corporation

Lin, Sue-mei 08 June 2009 (has links)
Founded in 1896, the Chunghwa Post Corporation, provided the people with the post services, savings and insurance by government organizational structure. In 2003, the Chunghwa Post Corporation reorgained its structure to be a national enterprise, in order to comply with the global trend and government policy. The business model was changed from service-oriented people to be a business-oriented enterprise. After reorgained, the Chunghwa Post Corporation adjust its operation goals, not only to serve the people with good quality but also to gain the profits for keeping the company subtainable and development . All the revenue of the post comes from the operantion of branch offices, espercilly from the Taiper Post Office where located in Taipei metropolitan area. We shall to know what the problem for the operation of Taipei branch offices after corporation. In this study, there are many problems under the discussions through the ten managers work in the Taipei branch offices, we get many suggestions and hope it will be a helpful for the future companys decision and policy-making. We found that to evalue the focus of performance of branch offices is unfair¡F double recheck of audictors will effect the routine operation of branch office¡F be kind to managers and staffs that hard work in branch offices and establish the good information system to support and reduce the mistake of business operations.
92

Pickup and delivery problems with side constraints

Qu, Yuan, Ph. D. 22 February 2013 (has links)
Pickup and delivery problems (PDPs) have been studied extensively in past decades. A wide variety of research exits on both exact algorithms and heuristics for generic variations of the problem as well as real-life applications, which continue to spark new challenges and open up new opportunities for researchers. In this dissertation, we study two variations of pickup and delivery problem that arise in industry and develop new computational methods that are shown to be effective with respect to existing algorithms and scheduling procedures found in practice. The first problem is the pickup and delivery problem with transshipment (PDPT). The work presented here was inspired by a daily route planning problem at a regional air carrier. In structuring the analysis, we describe a unique way to model the transshipment option on a directed graph. With the graph as the foundation, we implemented a branch and price algorithm. Preliminary results showed that it has difficulty in solving large instances. As an alternative, we developed a greedy randomized adaptive search procedure (GRASP) with several novel features. In the construction phase, shipment requests are inserted into routes until all demand is satisfied or no feasible insertion exists. In the improvement phase, an adaptive large neighborhood search algorithm is used to reconstruct portions of the feasible routes. Specialized removal and insertion heuristics were designed for this purpose. We also developed a procedure for generating problem instances in the absence of any in the literature. Testing was done on existing PDP data sets and generated PDPT data set. For the former, the performance and solution quality of the GRASP were comparable to the best known heuristics. For the latter, GRASP found the near optimal solution in most test cases. In the second part of the dissertation, we focus on a new version of the heterogeneous PDP in which the capacity of each vehicle can be modified by reconfiguring its interior to satisfy different types of customer demands. The work was motivated by a daily route planning problem arising at a senior activity center. A fleet of configurable vans is available each day to transport participants to and from the center as well as to secondary facilities for rehabilitative and medical treatment. To find solutions, we developed a two-phase heuristic that makes use of ideas from greedy randomized adaptive search procedures with multiple starts. In phase I, a set of good feasible solutions is constructed using a series of randomized procedures. A representative subset of those solutions is selected as candidates for improvement by solving a max diversity problem. In phase II, an adaptive large neighborhood search (ALNS) heuristic is used to find local optima by reconstructing portions of the feasible routes. Also, a specialized route feasibility check with vehicle type reassignment is introduced to take full advantage of the heterogeneous nature of vehicles. The effectiveness of the proposed methodology is demonstrated by comparing the solutions it provided for the equivalent of several weeks with those that were used in practice and derived manually. The analysis indicates that anywhere from 30% to 40% savings can be achieved with the multi-start ALNS heuristic. An exact method is introduced based on branch and price and cut for settings with more restricted time windows. In the procedure, the master problem at each node in the search tree is solved by column generation to find a lower bound. To improve the bound, subset-row inequalities are applied to the variables of the master problem. Columns are generated by solving the pricing subproblems with a labeling algorithm enhanced by new dominance conditions. Local search on the columns is used to quickly find promising alternatives. Implementation details and ways to improve the performance of the overall procedure are discussed. Testing was done on a set of real instances as well as a set of randomly generated instances with up to 50 customer requests. The results show that optimal solutions are obtained in majority of cases. / text
93

Dimension Relations of Branches in Hinoki (Chamaecyparis obtusa (Sieb. et Zucc.)Endl.)

HAGIHARA, Akio, 萩原, 秋男, YAMAJI, Kazuyoshi, 山路, 和義 11 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
94

Ambidexterity: the simultaneous pursuit of service and sales goals in retail banking

Yu, Yi-Ting , Marketing, Australian School of Business, UNSW January 2010 (has links)
Torn by having to meet the external demands of customers for quality service and internal demands for achieving sales targets, achieving a balance is not an easy task for traditional service units in fields such as retail banking, retailing, telecommunications, travel industry, and the like. This study examines the issue through the lens of an organizational ambidexterity framework. In the management literature, ambidexterity is used as a metaphor to describe an organization???s ability to perform seemingly conflicting tasks or pursue disparate goals simultaneously (Lubatkin et al., 2006). As an emerging research area, ambidexterity studies address the issue of how an organization can pursue multiple goals simultaneously (Benner & Tushman, 2003). The study has three specific objectives: 1) to conceptualize ambidexterity in the context of service and sales in a retail bank setting; 2) to identify and empirically examine the antecedents of branch ambidexterity; and 3) to examine the impact of ambidexterity on branch financial performance. Based on resource-based view and organization-context literature, the present study focuses on the impact of employee characteristics and contextual variables on branch ambidexterity and, ultimately, branch-level financial performance. The study uses both a qualitative and a quantitative approach. Data are collected from two large retail banks, one in Australia and one in Thailand. Findings are reported in three different studies. Study one reports findings based on the qualitative phase. Studies two and three report findings based on the quantitative data. A qualitative approach involves five bank branches and conducting a series of in-depth interviews with branch managers and frontline staff. It identifies employee constructs that have a positive or a negative impact on branch ambidexterity. These constructs are goal orientation, self-efficacy, and role stress. The role of branch context is also discussed. The quantitative approach involves data from 2,306 employees in 267 branches in a large Thai bank. Hierarchical linear modeling (HLM) is used to analyze the data. The quantitative data are used to test two models. The first model explores the direct impact of employees??? characteristics on branch ambidexterity. It is found that goal orientation, self-efficacy, and role stress are significantly associated with branch ambidexterity. The inclusion of transformational leadership as a moderator provides additional insights into the relationship between employee characteristics and branch ambidexterity. The second model tests the direct impact of contextual variables on branch ambidexterity. The contextual variables include empowerment, team support, fairness of rewards, and transformational leadership. Finally, it explores the impact of branch ambidexterity on branch financial performance. Data suggest that all four contextual variables make significant positive contributions to branch ambidexterity at the individual level. However, only empowerment, team support, and fairness of rewards have a significant group-level effect on branch ambidexterity. It is also found that branch ambidexterity is positively related to branch financial performance.
95

Freight railway crew scheduling models, methods, and applications

Albers, Marc January 2009 (has links)
Zugl.: Diss.
96

Algorithmes d'optimisation pour la résolution du problème de stockage de conteneurs dans un terminal portuaire / Optimization algorithms for the resolution of container storage problem at seaport terminal

Ndiaye, Ndèye Fatma 23 June 2015 (has links)
ADans cette thède, nous traitons le problème de stockage de conteneurs dans un terminal portuaire. Dans un premier temps, noux présentons une étude bibliographique dans laquelle sont analysés les travaux qui ont déhà été rélisé dans ce domaine. Ensuite, nous présentons une étude analytique, puis une modélisation mathématique et des méthodes de résolution numérique qui englobent des algorithmes efficaces. Nous proposons une démonstration de la compexité du problème de stockage de conteneurs en considérant différents cas de stockage. Ce problème étant "Np_difficile" peut être difficilement résolu avec le logiciel d'optimisation "ILOG CPLEX". », raison pour laquelle nous proposons un algorithme de banch-and-cut, qui est une méthode de résolution exacte et qui nous a permis de repousser les limites de "ILOG CPLEX". Nous avons aussi proposé des algorithmes métatheuristiques et des hybridations qui procurent des résultats très satisfaisants et qui sont très avantageux en temps de calcul. / AIn this thesis, we trait the container storage problem at port terminal. Initially, we present a state of the art in which the work that have been previously made in this filed are analyzed. After that, we present an analytical study. Thed we propose a mathematical modelling and some methods of resolution including effective algorithms. We propose a demonstration of the complexity of the problem by considering different cases of storage. This problme is "Np_difficult, so not always easy to solve by using the optimization software "ILOG CPLEX”. This is why we propose a branch-and-cut algorithm, wich is an optimal resolution algorithm and wich enables to go beyong the limits of "ILOG CPLEX". We also proposed meta-heuristic algorithms and hybridizations wich provide satisfactory resulys and wich required less calculation times.
97

Um método híbrido para o problema de dimensionamento de lotes / A hybrid method for the lot sizing problem

Luiz Henrique Cherri 27 February 2013 (has links)
Neste trabalho, abordamos métodos de resolução para o problema de dimensionamento de lotes que contempla o planejamento da produção de vários produtos em múltiplas máquinas. A fabricação dos produtos consome tempo de produção e preparação de uma capacidade de produção limitada. A demanda pelos produtos é conhecida e pode ser atendida com atraso durante um horizonte de planejamento finito. O objetivo é minimizar a soma dos custos de produção, preparação para a produção, estoque dos produtos e atraso na entrega destes. Em uma primeira etapa, desenvolvemos uma busca tabu determinística baseada em outra, aleatória, que foi apresentada na literatura. Com isso, realizamos uma análise sobre a influência de fatores aleatórios sobre heurísticas do tipo busca tabu quando aplicadas ao problema estudado. Posteriormente, desenvolvemos um método híbrido baseado em busca tabu, branch-and-cut e programação linear para a resolução do problema. Nos testes computacionais realizados, o método proposto mostrou-se competitivo quando comparado a outras heurísticas apresentadas na literatura / This paper proposes two methods to solve the capacitated lot-sizing problem with multiple products and parallel machines. The manufacturing of products consumes machines capacity (production time and setup time), which is scarce. The demand for the products is known and can be met with backlogging. The objective is to minimize the sum of production, setup, holding and backlog costs. In a first step, we developed a deterministic tabu search heuristic based on a random version from the literature and then conducted an analysis of the influence of random factors on tabu search heuristics when applied to solve the studied problem. Subsequently, we designed a hybrid method based on tabu search, branch-andcut and linear programming. Computational experiments show that this hybrid method is competitive with other heuristics presented in the literature
98

Projeto de acopladores branch-line com Banda dupla usando linhas de Transmissões artificiais

LIRA, Davi José Beltrão 13 April 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-03-08T12:15:41Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertaçãoDaviLira.pdf: 3636018 bytes, checksum: a3d66cf7d5a7e3e102b2d49abcabf422 (MD5) / Made available in DSpace on 2017-03-08T12:15:41Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertaçãoDaviLira.pdf: 3636018 bytes, checksum: a3d66cf7d5a7e3e102b2d49abcabf422 (MD5) Previous issue date: 2016-04-13 / O presente trabalho introduz um novo método para confecção de acopladores híbridos do tipo branch-line que sejam de banda dupla, ou seja, que são projetados para operar em duas frequências desejadas quaisquer com a mesma resposta. Este método faz uso de uma nova estrutura de linha de transmissão artificial (LTA) implementada em microfita, a qual é composta por três linhas de transmissões conectadas em cascata, com estubes em aberto inseridos em paralelo entre as linhas de transmissão. Foram obtidas expressões algébricas que determinam, em função das frequências das bandas desejadas, os valores de impedância característica e comprimento elétrico de cada um dos segmentos e estubes para que, em ambas as frequências, a LTA tenha os mesmos parâmetros de espalhamento que, e portanto seja equivalente a, um único segmento de linha de transmissão convencional com impedância característica e comprimento elétrico quaisquer especificados. Para obter o acoplador híbrido do tipo branch-line com banda dupla, portanto, substituímos cada linha de transmissão do acoplador por uma ATL com os parâmetros calculados de acordo com as expressões encontradas. Essa técnica foi usada para projetar, simular, fabricar e medir um acoplador híbrido branch-line que funcionasse nas frequências GSM de 925MHz e ISM 5.8GHz. Essa técnica tem como principal vantagem a capacidade e a flexibilidade de obter acopladores branch-line com bom desempenho em duas bandas quaisquer. / This work deals with a new method for the design of dual band branch-line hybrid couplers with arbitrary central frequencies, in other words, branch-line couplers which operate in two desired frequencies. This method makes use of a new artificial transmission line (ATL) structure, which is composed of the cascade connection of three transmission lines segments with parallel open stubs between them. Algebraic expressions were obtained that specify, in function of the central frequencies, the values for the characteristic impedance and electric length of the segments, so that the ATL has, for both frequencies, the same scattering parameters, hence the same behavior, as an ordinary transmission line with any chosen characteristic impedance and electric length. To obtain a dual band branch line coupler, the desired frequencies are chosen and the expressions are evaluated to find out the characteristic impedances and electric lengths of the ATL’s to replace all transmission lines that make up the coupler. This technique was used to design, simulate, fabricate and measure a branch-line hybrid coupler that works on the 925MHz GSM and 5.8GHz ISM frequencies. This technique has as it’s main advantage the ability and flexibility to yield couplers with good performance in two arbitrary bands.
99

Planejamento integrado da expansão de sistemas de distribuição de energia elétrica / Integrated planning of electric distribution systems

Oliveira, Marina Lavorato de 15 August 2018 (has links)
Orientadores: Ariovaldo Verandio Garcia, Marcos Julio Rider Flores / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-15T23:19:01Z (GMT). No. of bitstreams: 1 Oliveira_MarinaLavoratode_D.pdf: 1360671 bytes, checksum: e66710c118252edf8c3638375c56fdc7 (MD5) Previous issue date: 2010 / Abstract: In this work the Distribution System Integrated Planning (DSIP) problem is modeled as a mixed integer (binary) nonlinear program problem. Two techniques were investigated to solve this problem. First, a specialized Constructive Heuristic Algorithm (CHA) was implemented. A sensitivity index is used in each step of the CHA to add a circuit, a substation, a capacitor bank or a voltage regulator to the distribution system. This sensitivity index is obtained by solving the DSIP problem considering the numbers of circuits and substations to be added as continuous variables (the DSIP relaxed problem). The objective of the DSIP is to minimize the operation costs and the construction costs of circuits, substations, capacitors and voltage regulators, which are subjected to constraints of power balance, voltage magnitude, maximum circuit and substation capacities, taps control and radiality constraint. In addition, a local improvement phase to improve the initial solution of the CHA and a branching technique to avoid the infeasibility cases in the distribution system operation were included / Doutorado / Energia Eletrica / Doutor em Engenharia Elétrica
100

Otimização global determinística no espaço-imagem : problemas multiplicativos e fracionários / Deterministic global optimization in image-space : multiplicative and fractional problems

Ashtiani, Alireza Mohebi 21 August 2018 (has links)
Orientador: Paulo Augusto Valente Ferreira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-21T14:52:27Z (GMT). No. of bitstreams: 1 Ashtiani_AlirezaMohebi_D.pdf: 1381601 bytes, checksum: 9ae82bd53a7cf70422fed2348416f8f0 (MD5) Previous issue date: 2012 / Resumo: Muitos problemas práticos em Engenharia, Economia e Planejamento são modelados de maneira conveniente como problemas de Otimização Global. Esta tese tem como objetivo principal apresentar novas técnicas de Otimização Global com foco na resolução de duas importantes classes de problemas: problemas de Programação Multiplicativa Generalizada, os quais envolvem a minimização e a maximização de uma soma finita de produtos de funções convexas e côncavas, respectivamente, e problemas de Programação Fracionária Generalizada, os quais, por sua vez, envolvem a minimização e a maximização de uma soma finita de razões de funções convexa-côncava ou côncava-convexa, respectivamente. Na tese demonstra-se que todos estes problemas podem ser eficientemente resolvidos por um mesmo algoritmo de aproximação externa, a partir da reformulação dos problemas como problemas com infinitas restrições lineares de desigualdade. Um algoritmo baseado em enumeração de restrições e um algoritmo de aproximação externa combinado a uma técnica branch-and-bound são usados para resolver globalmente problemas de Programação Multiplicativa. Em seguida, as mesmas técnicas são empregadas na resolução de problemas de Programação Fracionária. Experiências computacionais atestam a viabilidade e a eficiência dos métodos de Otimização Global propostos, os quais também são facilmente programáveis a partir de pacotes de otimização disponíveis comercialmente / Abstract: Many practical problems in Engineering, Economics and Planning are modeled in a convenient way by Global Optimization problems. The principal objective of this thesis is to introduce new global optimization techniques with focus on the resolution of two important classes of problems: Generalized Multiplicative Programming Problems, in which involve the minimization and maximization of a finite sum of products of convex and concave functions, respectively, and Generalized Fractional Programming Problems, in which, in turn, involve the minimization and maximization of a finite sum of convex-concave and concave-convex ratio functions, respectively. The thesis demonstrates that all these problems can be efficiently solved by the same outer approximation algorithm, from the reformulation of the problems as problems with infinite linear inequality constraints. An algorithm based on a constraint enumeration and an outer approximation algorithm together with a branch-and-bound technique are used to globally solve Multiplicative Programming problems. Then, the same techniques are employed in the resolution of Fractional Programming problems. Computational experiments certify the viability and efficiency of the proposed Global Optimization methods, which are also easily programmable through commercially available optimization packages / Doutorado / Automação / Doutor em Engenharia Elétrica

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