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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.
1

Berth Schedule Planning of the Kaohsiung Port by Genetic Algorithms

Tsai, An-Hsiou 09 September 2011 (has links)
For a commercial port, to efficiently schedule the public berths is an important issue. Since a berth schedule would affect the usage of the commercial port, in this thesis, we apply a genetic algorithm to schedule the public berths in order to minimize the total waiting time of vessels. When in the initialization process, we encode the chromosome based on wharf characteristics in order to avoid assigning vessels to inappropriate wharves. After mutation process, we also adjust the usage of wharves to improve the speed of convergence speed. Simulation results show that the proposed algorithm can assign vessels to proper berths as soon as vessels arrive. Compared to the other genetic algorithms, the proposed algorithm obtains better performance in convergence speed and the quality of the solutions.
2

Berth and quay crane scheduling: problems, models and solution methods

Ak, Aykagan 17 November 2008 (has links)
A comprehensive study on berth and quay crane scheduling problems at container terminals at seaports is provided. Problems related to both multi-user terminals, where the terminal operator and liner carriers are different parties, and dedicated terminals, where liner carriers lease the terminal, are considered. A lower bound and an effective meta-heuristic algorithm are proposed for a dynamic variant of the Berth Allocation Problem (BAP). The Multiple Berth Allocation Problem (MBAP) is also introduced. Different crane scheduling methods used by terminal operators are analyzed and a tabu search algorithm is designed for a new variant of the Quay Crane Scheduling Problem (QCSP). The Simultaneous Berth and Quay Crane Scheduling Problem (BQCSP) is introduced with a lower bound analysis and an efficient solution method. A computational analysis is performed which exposes the substantial benefit of simultaneous planning over the hierarchical approach currently used by terminal operators. The tactical level Voyage and Berth Scheduling Problem (VBSP) is defined and a mathematical model based on multi-commodity network flow is presented. Constraints related to transshipments, terminal time windows and service level requirements are incorporated into the model, and how to modify instance data to increase schedule reliability is discussed.
3

Container Terminal Operations Modeling through Multi agent based Simulation

Ayub, Yasir, Faruki, Usman January 2009 (has links)
This thesis aims to propose a multi-agent based hierarchical model for the operations of container terminals. We have divided our model into four key agents that are involved in each sub processes. The proposed agent allocation policies are recommended for different situations that may occur at a container terminal. A software prototype is developed which implements the hierarchical model. This web based application is used in order to simulate the various processes involved in the following operations on the marine side in a case study of a container terminal in Sweden by adopting a multi-agent based simulation technique. Due to the increase in usage of container transportation, container terminals are experiencing difficulties in the management of the operations. The software provides a decision support capability to terminal managers for scheduling and managing the operations effectively while also visually presenting the time it takes to complete the process and its associated cost. Terminal managers need to implement certain policies to improve the management and operations of the container terminal. The policies are evaluated and tested under various cases to provide a more comparative overview. The results of the simulation experiments indicate that the waiting time for arriving vessels is decreasing when in queue with more than three vessels arriving on same day. / Simulation is a good technique that help analyst to take decision considering each factor of problem that is to be simulated. Simulation in addition with multi agent environment provides better understanding of modeling the entities. The complexity of CT environment and multiple involvement of agents simultaneously enables CT suitable domain for multi agents. We have modeled the four CT operations that are carried out at each CT. These operations are modeled in hierarchical sequence like berth allocation, QCs allocation, Transport vehicles allocation and YCs allocation. The most important factor of simulation is the measurement of dynamic time of each operation. We have simulated and compared different agents active time and service time compared with associated cost. The berth allocation is very important asset from all the operations that are carried out at the CTs. The effective utilization of FCFS berth allocation policy reduces the vessel waiting time in waiting queue. The developed terminal simulator tool allocates all resources dynamically while looking at the number of containers that will be loaded and unloaded at QS and yard storage area. The result of simulation tool presents the good dynamic allocation of transport vehicles. The dynamic resource allocation helps to minimize the congestion and bottlenecks that may occur at CTs. The result of three experiments depicts that the berth allocation and agent allocation is improved and vessel service time is reduced at berth side which automatically reduces vessels waiting time in queue. Besides this the transport allocation and YCs allocation is dynamically assigned by looking at number of containers in the vessels. The terminal simulator helps managers to analyze the simulated results and take better decision at hand.
4

Optimalizační procesy v přístavním kontejnerovém terminálu

Stehlíková, Blanka January 2008 (has links)
Cíle diplomové práce jsou popsat procesy probíhající v kontejnerovém přístavním terminálu, vytvořit přehled rozhodovacích problémů vznikajících v kontejnerovém přístavním terminálu z hlediska úrovně jejich typu řízení a plánování (strategické, taktické a operativní) a formulovat vybrané rozhodovací problémy a matematicky je analyzovat.
5

Study on Berth Operability due to Met-Ocean Data in Upper Gulf of Thailand / タイ湾奥の海象データを用いた係留地の稼働率に関する研究

Wissanu, Hattha 25 September 2017 (has links)
全文ファイル差し替え(2021-06-07) / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20675号 / 工博第4372号 / 新制||工||1680(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 平石 哲也, 准教授 馬場 康之, 准教授 森 信人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
6

Simulation and analysis of port bottlenecks: the case of Male'

Adam, Shammoon January 2009 (has links)
Maldives is an island nation that consists of around 1190 islands located in the Indian Ocean, southwest of Sri Lanka. The country virtually imports everything it consumes. Male’ Commercial Harbour handles all international sea cargo for the country. The land area assigned for the port is small; and there are frequent bottlenecks and congestion in the port. By using computer simulation techniques, this research investigates the situation of Male’ Commercial Harbour and identifies logistic bottlenecks that exist at the port. Accordingly, a field research was conducted at Male’ Commercial Harbour to collect required data. Both, qualitative and quantitative data were collected using focus group, interviews, on-site observations, and time and motion measures. The simulation models presented in this thesis were carried out with Arena software (Academic Version of Arena 10.0). The models were used to analyse the vessel turnaround time, berth capacity, yard capacity, container dwell time, queue values, utilisation of ship cranes and other container handling equipment. The results show that berth capacity seems to be the major bottleneck that creates longer queues and ship delays at Male’ Commercial Harbour. Several scenarios were tested to identify the best scenario regarding ship waiting time at berth. Based on the best scenario, a project was proposed focusing on the development of an extended alongside berth at Male’ Commercial Harbour. A cost benefit analysis was performed to see whether the project is financially feasible.
7

Um modelo matemático para otimizar o descarregamento de navios num terminal graneleiro / A mathematical model to optimize the unloading of ships in a grain terminal

Cereser, Bruno Luís Hönigmann, 1988- 23 August 2018 (has links)
Orientadores: Luiz Leduino de Salles Neto, Antonio Carlos Moretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-23T22:02:01Z (GMT). No. of bitstreams: 1 Cereser_BrunoLuisHonigmann_M.pdf: 8696662 bytes, checksum: b4ca681ecf08f10afa47d00b3a879e9e (MD5) Previous issue date: 2013 / Resumo: O transporte marítimo é fundamental para grandes empresas de caráter global. Em 2009 80% do comércio mundial foi realizado via transporte marítimo e desde então esse número só tem crescido. Devido a esse alto fluxo nos portos mundiais, surgiu o problema de alocação de navios em berços, que tem por finalidade estabelecer uma sequência de atendimento de navios para cada berço disponível no cais, visando minimizar o tempo total da operação e espera dos navios dentro dos portos. Nesse trabalho o problema de alocação de navios em berços será abordado considerando berços dependentes, e também a divisão das máquinas portuárias em berços consecutivos aplicados a terminais do Porto de Tubarão (ES). Para a representação matemática dos processos desses terminais do porto de tubarão foram desenvolvidos novos modelos matemáticos. Os testes computacionais foram exitosos / Abstract: The maritime transportation is essential to global companies. In 2009 80% of global trade was made by maritime transportation, and over the year this number has raised. Because of this high flux, the BAP (Berth Allocation Problem) arose. The BAP have intent to discovery the vessel allocation sequence in every berth with the minimum total wait time. In this work, the berths of BAP will be considered dependents, we also considered the division of portuary machines between consecutive berths. The objective of this work is the mathematical representation of the terminals Produtos Diversos and Praia Mole of the Tubarão port. For this reasons we propose here unprecedented mathematical models / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada
8

[en] DECISIONS TO INVEST IN WATERWAY TERMINALS FOR OIL AND OIL PRODUCTS / [pt] DECISÕES DE INVESTIMENTO EM TERMINAIS AQUAVIÁRIOS DE PETRÓLEO E DERIVADOS

22 March 2021 (has links)
[pt] Decisões de investimento em terminais aquaviários, onde são realizadas movimentações e armazenagem de petróleo e derivados, devem levar em conta aspectos relativos aos custos logísticos envolvidos bem como a existência de flexibilidades gerenciais. O objetivo principal deste trabalho é propor uma metodologia de avaliação de investimentos para este tipo de unidade com ênfase nas futuras incertezas e avaliar um projeto selecionado em um terminal aquaviário brasileiro com o intuito de solucionar uma de suas principais restrições que acaba por gerar custos excessivos de sobreestadia à operação. O passo a passo proposto deverá ser refletido em outras análises da companhia de óleo e gás, cuja subsidiária opera o terminal em questão. A avaliação econômica do projeto leva em conta a modelagem de incertezas e as flexibilidades existentes, à luz da Teoria de Opções Reais. A relevância deste trabalho para a literatura está na aplicação de uma avaliação de Opções Reais em um projeto de um terminal aquaviário privado brasileiro, cenário pouco explorado pelos autores desta área no país, dando ênfase à ocupação de seus berços e aos custos de sobreestadia. A contribuição se dá através do framework proposto para análises de investimentos em terminais e da quantificação dos ganhos com a implantação do projeto avaliado, que elimina algumas restrições operacionais atuais. Além disso, espera-se que a empresa de óleo e gás divulgue a metodologia internamente e passe a adotá-la formalmente em suas avaliações de investimentos em Logística, iniciando, inclusive, um processo de mudança cultural nas áreas responsáveis pelos projetos e na mentalidade dos tomadores de decisão. O desenvolvimento do estudo envolve coleta e análise estatística de dados, entrevistas com operadores do terminal e especialistas da empresa, aprofundamento em técnicas de Opções Reais, análise de sensibilidade nas variáveis relevantes e discussão com demais colaboradores interessados no assunto. Os resultados mostram que há valor na espera pela realização do investimento, aqui analisado em duas escalas. / [en] Decisions to invest in waterway terminals, where oil and oil products are moved and stored, should take into account aspects related to the logistics costs involved, as well as the existence of managerial flexibilities. The main objective of this work is to propose a methodology for the evaluation of investments for this type of unit with emphasis on future uncertainties and to evaluate a selected project in a Brazilian waterway terminal with the purpose of solving one of its main restrictions that ends up generating excessive costs of demurrage to the operation. The proposed step-by-step should be reflected in other analyzes of the oil and gas company, whose subsidiary operates the terminal in question. The economic evaluation of the project takes into account the modeling of uncertainties and the existing flexibilities, in the light of the Real Options Theory. The relevance of this work to the literature is the application of an evaluation of Real Options in a project of a Brazilian private waterway terminal, a scenario little explored by the authors of this area in the country, with emphasis on the occupation of its berths and the costs of demurrage. The contribution is made through the proposed framework for analysis of investments in terminals and the quantification of gains with the implementation of the evaluated project, which eliminates some current operational restrictions. In addition, the oil and gas company is expected to disclose the methodology internally and to formally adopt it in its Logistics investment assessments, including initiating a process of cultural change in the areas responsible for the projects and in the decision makers. The development of the study involves statistical data collection and analysis, interviews with terminal operators and company specialists, deepening of Real Options techniques, sensitivity analysis in the relevant variables and discussion with other collaborators interested in the subject. The results show that there is value in waiting for the investment, analyzed here in two scales.
9

Profesionalizace neziskového sektoru v ČR: analýza poptávky po profesích v nestátních neziskových organizacích / Professionalization of the Nonprofit Sector in the Czech Republic: Analysing the Demand for Professions in the Non-governmental Non-profit organisations

Bezděková, Jana January 2014 (has links)
The thesis deals with the professionalization of non-profit sector in the Czech Republic, specifically the problém what "professions" in the non-profit sector in the Czech Republic are formed and what are their parameters. The thesis analyzes the jobs offered in the labor market in non-profit organizations. This thesis tries to answer the question: "To what jobs are employees of nonn-governmental organizations demanded" It also focuses on the requirements of these jobs - specifically, the required education, skills, abilities, personality characteristics, experrience, knowledge, relationship to work and the technical prerequisites. The theoretical part is devoted to the professionalization of NGOs in the country. First, I define the Non-Governmental Organization, then explain the concept of professionalization, explain the concept of profession and define who is a professional. The last chapter concerns human resources and positions in non-profit organizations. In the empirical part I analyze the current situation on the labor market in the Czech Republic. It is mentioned what positions of the NGOs are demanding and what are the requirements put on these posts, then I compare the offers of work in NGOs in each region.
10

PROBLEMA DE ALOCAÇÃO DE BERÇOS EM PORTOS GRANELEIROS COM RESTRIÇÕES DE ESTOQUE E CONDIÇÕES FAVORÁVEIS DE MARÉ / PROBLEM OF ALLOCATION OF CRADLES IN PORTS GRANARY SHIPS WITH SUPPLY RESTRICTIONS AND CONDITIONS FAVORABLE OF TIDE

Barros, Victor Hugo 22 March 2010 (has links)
Made available in DSpace on 2016-08-17T14:53:08Z (GMT). No. of bitstreams: 1 Victor Hugo Barros Silva.pdf: 4177386 bytes, checksum: 324ffa71e5b64047e7a54ab199bb9241 (MD5) Previous issue date: 2010-03-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The problem of allocating berth positions for vessels in tidal grain port terminals is discussed in this work. A berth defines a specific location alongside a quay where a ship loader is available for loading or unloading vessels, accommodating only one vessel at time. In tidal ports, draft conditions depend on high tide conditions, since available depth under the low tide is not adequate to the movement of ships. Some port terminals at the port complex of São Luís, Maranhão, are associated to important transnational enterprises which maintain a strong control over the stock level of their goods. Since the stock level sometimes depends on a continuous process of consumption or production of grains, the decision making of loading or unloading vessels must contemplate the amount of the grain stored in the port yards. Therefore, a basic criterion for decision making is to give priority to the vessels related to the most critical grain stock level. This paper presents two integer linear programming models based on the transportation problem to represent the discussed problem. Some problem instances could be solved by a commercial solver. As an alternative to larger instances, which require large running time, an implementation of Simulated Annealing (SA) and the algorithm known as Population Training Algorithm for Linear Programming (PTA/LP) are used to solve the problem. / O Problema de Alocação de Berços em Portos Graneleiros com Restrições de Estoque e Condições Favoráveis de Maré é abordado neste trabalho. Um berço define um local especifico ao longo do cais onde um carregador de navio está disponível para carregar ou descarregar navios, acomodando apenas um navio por vez. Em portos que sofrem a influência da variação das marés, as condições de navegação dependem de condições favoráveis de maré, uma vez que a profundidade na maré baixa restringe a movimentação de navios. Alguns terminais no complexo portuário de São Luís, Maranhão, estão associados a importantes empresas multinacionais que mantêm um forte controle sobre os níveis de estoque de seus produtos. Uma vez que o nível de estoque, por vezes, depende de um processo contínuo de consumo ou produção de granéis, a tomada de decisão de carregar ou descarregar navios deve levar em conta as cargas armazenadas nos pátios do porto. Desta forma, um critério básico para tomadas de decisão é dar prioridade aos navios relacionada aos níveis mais críticos de estoque. Este trabalho apresenta dois modelos de programação linear baseado no problema de transporte para representar o problema abordado. Algumas instâncias do problema puderam ser resolvidas por um solver comercial. Como alternativa suas instâncias maiores, que exigem grande tempo de execução, uma implementação do Simulated Annealing (SA) e do algoritmo conhecido como Algoritmo de Treinamento Populacional para Programação Linear (ATP/PL) são empregadas para resolução do problema.

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