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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.
111

Requisitos para modelo de operação da cabotagem de cargas conteinerizadas no Brasil: a utilização de terminais rápidos. / Requirements for operational model of short sea shipping of containerized cargo in Brazil: the use of fast terminals.

Valois, Nayara Amaral Lima de 07 October 2014 (has links)
Este estudo propõe requisitos para a adequação da operação de cabotagem de contêineres nos terminais portuários brasileiros. Esta adequação transforma os terminais convencionais em terminais marítimos denominados aqui como rápidos. O conceito de terminais eficientes utilizado pelo projeto europeu Motorways of the Sea - MoS serviu como referência para o desenvolvimento da proposta. A metodologia utilizada fundamentou-se na coleta de dados através de entrevistas semiestruturadas a usuários da cabotagem, além de questionário online com especialistas e simulação por eventos discretos da operação de cabotagem. As respostas das entrevistas direcionaram o estudo para fatores de melhorias relacionados a processos de liberação da carga por parte de órgãos de fiscalização, custos portuários e controles alfandegários. A avaliação das respostas do questionário online se fez por meio de uma variação da técnica Delphi com Q-sort que consolidou as respostas em cinco categorias: administrativo/fiscal, custos, hinterlândia, infraestrutura e operacional. O modelo de simulação de eventos discretos verificou os dados operacionais e avaliou as diferenças entre a operação dos terminais convencionais e de terminais compatíveis com o modelo do projeto MoS. Os principais requisitos propostos são: a melhoria no processo de fiscalização com a simplificação nas inspeções e liberações das cargas; a redução de fretes para transporte de carga porta-a-porta; a existência de acessos terrestres (rodoviário/ferroviário) para interconexões entre os modais; a disponibilidade de infraestrutura adequada (equipamentos) para uso nos terminais; e a minimização de tempos operacionais e de entrega porta-a-porta. Uma derivação da técnica Matriz QFD (Quality Function Deployment) foi utilizada para obtenção do sequenciamento dos requisitos propostos. O estudo verificou que a aplicação dos requisitos salienta as oportunidades de melhorias na operação de cabotagem nos terminais brasileiros. Também ficou evidenciado a possibilidade de adequação dos terminais convencionais em terminais rápidos, mediante a aplicação do sequenciamento obtido para os requisitos propostos. / This study proposes requirements for the adequacy of Short Sea Shipping (SSS) operation in Brazilian container port terminals. This adaptation transforms conventional port terminals into maritime terminals called \"fast\". The concept of \"eficient terminals\" of the European project Motorways of the Sea MoS served as reference for the development of this proposal. The methodology was based on data collection through semi-structured interviews with SSS users as well as an online questionnaire with experts and discrete event simulation of SSS terminals. The responses from the interviews directed the study to factors related to processes of cargo release by regulatory agencies, port costs and customs controls. The evaluation of the online questionnaire responses was done by means of a variation of the Delphi technique with Q-sort that consolidated the responses in five aspects: administrative, costs, hinterland, infrastructure and operational. The discrete event simulation model verified operational data and evaluated the differences between the operation of conventional terminals and those compatible with the MoS project model. The main proposed requirements are: the process improvement to reduce inspections and cargo clearances, the freight reduction on cargo door-to-door transportation, the existence of land access (road/rail) for interconnections between modes, the availability of adequate infrastructure (equipment) for terminal use and the decrease of operating times and door-to-door delivery. The Quality Function Deployment (QFD) matrix technique was used to obtain a sequencing order for the proposed requirements. The study found that the requirements application highlights the improvement opportunities in SSS operation in Brazilian terminals. It was also evidenced the possibility of conversion of these conventional terminals on \"fast\" terminals, with the requirements sequencing order application.
112

Modelo de margem de contribuição aplicado ao planejamento de marketing no transporte marítimo regular de contêineres. / Contribution margin model applied to the marketing planning in the container liner service.

Costa, Gustavo Adolfo Alves da 22 June 2006 (has links)
Este trabalho apresenta o panorama atual da indústria do transporte marítimo regular de contêineres e o mercado em que atua, concluindo que o crescimento da atividade econômica mundial, e conseqüentemente na demanda de transporte, exige maiores investimentos por parte dos armadores para adequação da oferta de capacidade de transporte e de rotas, aumentando a competição entre os mesmos. Os processos de globalização, desregulamentação e de concentração alteram significativamente nível de competição da indústria, tornando os armadores de baixa lucratividade em potenciais alvos para aquisições por parte de empresas mais competitivas e lucrativas. A implementação de contratos de serviços entre um armador e seus clientes, decorrentes da OSRA 1998, demandam uma revisão na metodologia aplicada em seu planejamento de marketing&sales , de forma a torná-lo mais científico, com uma maior utilização de ferramentas de pesquisa operacional, uma vez que a seleção dos clientes com os quais terá contratos, a duração destes, os níveis de fretes e os imbalances decorrentes destes contratos são fatores fundamentais para a sua rentabilidade. A possibilidade de utilização de um modelo de sistema de apoio a decisão, baseado em margem de contribuição, no planejamento de marketing&sales de um armador motivou a elaboração de uma metodologia para desenvolvimento de uma ferramenta de apoio à decisão, na qual os parâmetros relativos à demanda de transporte, capacidades, custos e receitas podem ser testados para análise da atuação do armador no mercado, visando a seleção de cargas e clientes que maximizam a margem bruta de contribuição dos fretes. A metodologia adotada e o modelo desenvolvido em programação linear mostram-se bastante consistentes e seus resultados apresentam uma boa aderência à realidade encontrada na indústria, uma vez que, os problemas normalmente apresentados no planejamento de marketing&sales de um armador são tratados e solucionados pelo modelo. / This work presents the current view about liner shipping industry and the market where it acts, summing up that the growth of world economic activity, and consequently in the demand of transport services, requires greater investments from the shipping lines in order to adjust their transport capacities and routes, increasing the competition among them. The globalization processes, deregulation and concentration changed the level of industry competition significantly, becoming the shipping lines with low profitability in white potentials for acquisitions on the part of more competitive and lucrative shipping lines. The service contracts implementation between a shipping line and its customers, as a result of OSRA 1998, demands a revision in the methodology applied in its planning of marketing & sales, enabling it more scientific with a bigger use of operational research tools, since the customers election based on service contracts and its validity, the freights level and the imbalances pertaining to said contracts are basic factors for its yield. The possibility of use a decision support system, based on contribution margin, in the shipping line's planning of marketing & sales, motivated the elaboration of a methodology for development of a decision support tool where the relative parameters to the demand of transport, capacities, costs and revenue can be tested for better shipping line performance analysis in the market, aiming the election of shipments and customers that maximize the freights' gross contribution margin. The adopted methodology and the model developed in linear programming reveal sufficiently consistent and its results present a good tack to the reality found in the industry, since the problems usually presented in the shipping line's planning of marketing & sales are treated and solved thru the model.
113

Otimização da seleção e alocação de cargas em navios de contêineres. / Optimization of cargo selection and alocation in container ship.

Cuoco, Marcello 25 September 2008 (has links)
Este trabalho trata do problema de otimização do resultado para uma empresa (maximização da receita) que presta o serviço de transporte de carga conteinerizada por via marítima num cenário onde a demanda dos clientes supera a oferta de capacidade disponível. No trabalho são descritas as características do problema da escolha do mix de carga em um horizonte de planejamento típico de várias semanas (tipicamente de 6 a 8) com detalhamento diário, ou seja, caracterizando um problema de múltiplos períodos. Também são consideradas as restrições de peso e de volume dos navios utilizados e disponibilidade de contêineres. A proposta é maximizar o retorno gerado pelo transporte através da escolha do conjunto de clientes que apresentem a melhor rentabilidade total dentre um universo definido em um processo mensal de levantamento de demanda. Contribuem para o aumento da complexidade da modelagem do problema a necessidade de utilização de variáveis inteiras em função da escolha de cada carga de cada cliente, considerando também vários navios em múltiplas rotas e programação do reposicionamento de contêineres vazios em conjunto com os cheios. Para a resolução deste problema foi desenvolvida uma heurística para a solução do modelo matemático que analisa a rentabilidade relativa de cada carga segundo critérios de ocupação (volume e peso) dos navios. A partir daí, as cargas mais rentáveis são alocadas e são verificadas as restrições de capacidade do navio utilizado e a disponibilidade de contêineres vazios em um processo interativo, onde são analisadas as opções de reposicionamento dos contêineres vazios até a obtenção da solução ou recusa da carga. A heurística proposta permite considerar diferentes critérios de rentabilidade dos clientes e cargas, tendo sido aplicada a um problema real para a sua validação. Os resultados obtidos mostram uma oportunidade de melhoria no processo atual tanto no aspecto de aumento da lucratividade do negócio, objetivo principal do trabalho, como em outras questões como a programação antecipada do reposicionamento dos contêineres vazios e a flexibilização do espaço alocado para esta movimentação. / This work presents a problem of profit optimization (revenue maximization) in container shipment company by maritime modal in a scenario where demand surplus the available capacity. In this work is described the characteristics of cargo mix problem in a multiple planning period of several weeks (typically from 6 to 8) with diary scheduling, which means that it turns to a multiple period problem. It is also considered the weight and volume restrictions of the boats and availability of containers. The proposal is to maximize the return generated by the transportation service by choosing the set of clients that generates the bigger profitability in a major group defined in a monthly process of demand evaluation. The complexity of the problem is enhanced by the utilization of integer variables, because of the need of choosing each client and its cargo, also considering that it may be more than one ship in multiple routes and the empty containers transportation along with the cargo. For the solution of the problem, it was developed a heuristic for the solution of the mathematical model that analyses the profitability of each client according to occupation (volume and weight) of the ships. From this moment on, the most profitable cargos are allocated and the restriction of capacity of the ships and availability of empty containers are in a interactive process until the solution is found or the client discharged. This method was tested in a real problem of a maritime transportation company, comparing the various profitability criteria of the clients and cargos. The obtained results show an opportunity of actual process improvement concerning the profitability of the business, main objective of this work, as in the anticipation of the empty containers repositioning and flexibilization of the space allocated to this operation.
114

Migration of chemicals through coated paperboard for food contact packaging

Skillington, Pauline January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Chemistry in the Faculty of Applied Sciences at the Cape Peninsula University of Technology / Paperboard made from recycled fibres is being used more frequently in direct food packaging applications, in addition to its use as secondary and tertiary packaging. However, recent research has shown that there is a risk that harmful chemicals may migrate from the paperboard into the food. The simplest approach to reducing the migration of these contaminants is the use of barrier films. The barrier efficiencies of these various films can be examined by means of a migration test into a food simulant, followed by extraction in a suitable solvent. The extract can then be analysed by chromatographic techniques such as gas chromatography mass spectrometry (GC-MS) to determine the concentration of the specific contaminants. However on a production level, the availability of this type of highly specialised equipment is limited. A simple, cost effective method is needed to evaluate the barrier properties to specific chemical contaminants. The Heptane Vapour Transmission Rate (HVTR) test is a permeation test method for use at quality control level to determine barrier properties to the migration of organic vapours. The first part of the study focussed on establishing a universal correlation between HVTR and specific migration of diisobutyl phthalate (DiBP), dibutyl phthalate (DBP) and diethylhexyl phthalate (DEHP) that would be applicable to any type of functional barrier. However, experimental data demonstrated this was not possible as the correlation factor linking HVTR to specific migration was largely dependent on the type and morphology of the coating considered. The initial objective of the study was reconsidered in favour of building individual models specific to the nature of the coating and substrate considered. A correlation between HVTR and specific migration of DiBP, DBP and DEHP for a polyvinylidene chloride (PVDC) barrier polymer was constructed by varying the applied coating weight. The vapour transport mechanism for the HVTR test and the specific migration test were found to differ, showing that a direct correlation between HVTR and the specific migration was again not possible. However, an indirect correlation could be made. The HVTR method gives an indication of film integrity, whereas the coating weight could be used as an indicator of the specific migration. The correlation between the coating weight and the specific migration yielded an equation that can be used to calculate the specific migration through the PVDC barrier polymer, provided the quantity of the chemical contaminant originally present in the paperboard was known. This equation was specific to the type of barrier polymer, the specific chemical contaminant as well as the intended shelf-life of the food product to be packaged in the paperboard.
115

Uso de containers refrigerados para o armazenamento de produtos agricolas / Using of refrigerated containers from storage of agricultural produces

Teruel Mederos, Barbara Janet, 1966- 20 August 1996 (has links)
Orientador: Luis Augusto Barbosa Cortez / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-09-11T20:52:16Z (GMT). No. of bitstreams: 1 TeruelMederos_BarbaraJanet_M.pdf: 10068926 bytes, checksum: 69f9a39617cd8616194badfd7f6c82d0 (MD5) Previous issue date: 1996 / Resumo: A refrigeração é o único método para o armazenamento prolongado de produtos agrícolas como frutas e hortaliças frescas, entre outros. Em muitos produtos perecíveis, a qualidade comestível pós-colheita, aumenta e depois diminui rapidamente se não for utilizado o armazenamento a frio. As deteriorações são mais rápidas devido ao processo de respiração, onde há liberação de calor, além de CO2 e vapor d' água. O uso de containers, para fins de refrigeração, toma-se hoje uma alternativa muito interessante quando se trata de prolongar o tempo de comercialização, devido aos altos custos de investimento para câmaras frigoríficas estáticas. Existe também a necessidade de geração de tecnologias simples e de fácil utilização, pelo pequeno e médio produtor, que permitam a manutenção da qualidade dos produtos. No entanto, na América Latina e particularmente no Brasil, há perdas significativas pós-colheita principalmente onde há falta de armazenagem refrigerada. A título de exemplo a cidade de São Paulo registra grandes perdas de frutas e hortaliças principalmente no verão, podendo atingir até 15% do total comercializado, e para alguns produtos estimadas em até 50%. Entre as principais vantagens destes containers estão: possibilidades de aluguel ("sistema leasing") por tempo determinado, faixa de temperaturas de -25°C a +25 °C, adaptando-se aos diferentes produtos agrícolas, facilidade de operação, além de poder ser transportado carregando a produção a longas distâncias. Este trabalho tem como objetivo geral, determinar os critérios básicos para fazer uma avaliação técnica e econômica da possibilidade do uso de containers refrigerados para o armazenamento de produtos agrícolas, fundamentalmente frutas tropicais, produtos estes de grande demanda no mercado interno e internacional. Especificamente neste trabalho foram desenvolvidos uma série de experimentos com o container submetido a dois regimes: vazio e com carga térmica simulada com um banco de resistências elétricas, com carga de 10 kW. Foram avaliados parâmetros como: temperatura, velocidade do ar, umidade relativa, e pressões do sistema frigorífico / Abstract: Refrigeration is the most important method to extend storage of horticultural produces such as fresh fi-uitsand vegetables. As it happens with many perishable produces, the postharvest quality increases and then decreases rapidly if refrigerated storage is not used. The deterioration is fast due to the respiration process, which involves the release of heat, CO2and water. Use of refrigerated containers is actually an interesting altemative to extend the storage life of horticultural produces, due to the high investment cost of static cold chambers. Meanwhile, in Latin-America, particularly in Brazil, there is significant postharvest losses, speciallywhere refrigeration is not used. For example, São Paulo city presents great losses of horticultural produces, mainly during summer, reaching from 15% to 50% of total marketable produces. The main advantages of the refrigerated containers compared to refrigerated room are: leasing system for convenient periods; their range temperature of -25°C to 25°C, their the adaptability to different agricultural produces; the possibility of using them for produce transportation for long distances and the handling operation. The general objective of this work is to determine to basic criteria for the technical and econornical evaluation of the possibility of using refrigerated containers for horticultural produce storage, speciallytropical fi-uitswhich have great demands for national and intemational market. The tests were conducted to determine the container refrigeration capacities using electrical resistances to simulate thermal loads. The evaluated parameters were: the temperature, relative humidity, air velocity and pressure of refrigeration systems / Mestrado / Mestre em Planejamento de Sistemas Energéticos
116

Hybridation d’algorithme génétique pour les problèmes des véhicules intelligents autonomes : applications aux infrastructures portuaires de moyenne taille / Hybrid genetic algorithm for autonomous intelligent vehicles problems : Applications to middle size of container terminals.

Zaghdoud, Radhia 17 November 2015 (has links)
L’objectif de ce travail est de développer un système d’affectation des conteneurs aux véhicules autonomes intelligents (AIVs) dans un terminal à conteneurs. Dans la première phase, on a développé un système statique pour résoudre le problème multi-objectif optimisant la durée totale des opérations de déplacement des conteneurs, le temps d’attente des véhicules aux niveaux de points de chargement et de déchargement et l’équilibre de temps de travail entre les véhicules. L’approche proposée est l’algorithme génétique(AG). Une extension de cette approche a été ensuite effectuée pour corriger les limites de la précédente. Pour choisir la meilleure approche, une étude comparative a été réalisée entre trois approches : AG, AG & DIJK et AG & DIJK & HEUR. Les résultats numérique ont montré que l’approche AG & DIJK & HEUR est meilleure. Dans la deuxième phase, on a étudié la robustesse de notre système dans un environnement dynamique. Un retard de l’arrivée d’un navire au port ou un dysfonctionnement de l’un des équipements peutperturber le planning des opérations et donc influencer sur les opérations d’affectation des conteneurs. L’idée était d’ajouter les nouveaux conteneurs aux véhicules qui sont déjà non disponibles. D’autres cas de perturbation comme la congestion routière, la non disponibilité de certaines portions de la routes ont été étudiés expérimentalementEt les résultats numériques ont montré la robustesse de notre approche pour le cas dynamique.Mots-clés : Conteneurs, AIV, routage, optimisation, algorithme génetique, environnement dynamique. / The objective of our work is to develop a container assignment system for intelligent autonomous vehicles (AIVS) in a container terminal. Given the complexity of this problem, it was proposed to decompose it into three problems: The problem of dispatching containers to AIVS, the AIVS routing problem and the problem of scheduling containers to queues of AIVS. To achieve this goal, we developed in the first phase, a static system for multi-objective problem to optimize the total duration of the containers transportation, the waiting time of vehicles at loading points and the equilibrium of working time between vehicles. The approach used was the genetic algorithm (GA). This approach was applied to optimize only the assignment operation without influence on the choice of the path traveled by each AIV. An extension of this work was then made to improve the results found. For this purpose, a comparative study was carried out between three approaches: The first approach is the AG, the second approach is the GA and the Dijkstra algorithm (DIJK) that was used to find the shortest path for each vehicle and the third approach is the AG and DIJK and heuristic (HEUR) which was proposed to choose the nearest vehicle of each container. The numerical study showed the best performance of the AG & DJK & HEUR approach over the other two approaches. In the second phase of our project, the robustness of our system in a dynamic environment has been studied. A delay of the arrival of a ship at the port or malfunction of one of any equipment of the port can cause a delay of one of the operations of loading or unloading process. This will affect the container assignment operation. The idea was to add new containers to vehicles that are already unavailable. The traffic can also cause a delay in arrival of the vehicle at the position of the container or the unavailability of one of the paths crossing point. These cases were investigated experimentally, numerical results showed the robustness of our approach to dynamic case.
117

Placering av lastbärare : Faktorer som styr placeringen av lastbärare i terminal

Sahlin, Sofia January 2009 (has links)
<p> </p><p> </p><p> </p><p><strong>Purpose</strong>: The Essay is written on behalf of a company called ”Uppdragsgivaren”. The purpose is to connect theory with the result of the survey and thereby find the critical factors for an optimal placement of the cargo holders in the company’s terminal.</p><p> </p><p> </p><p> </p><p><strong>Method:</strong> A qualitative case study has been carried out. The theory collection is completed with the result from the survey, which include the information “Uppdragsgivaren“ provides and the result from the survey. The survey is completed with telephone interviews. The survey is sent to seven persons working on similar company as “Uppdragsgivaren”. The study has a combination between the positivistic and hermeneutic view. The result is treated deductive. Theory and empirical are connected and among several theories one is chosen and will be tested on the company. Recommendations are given to “Uppdragsgivaren” and so are suggestions on further studies.</p><p> </p><p><strong>Result:</strong> The test shows that one part of the model is possible for “Uppdragsgivaren” to use when they want to optimize the cargo holder terminal. Part one of the tested model is independent from frequency and volume, and is therefore not applicable. Part two is applicable and the cargo holders can be arranged based on their volume. The result is thus that the most frequent cargo holder shall be placed on the most accessible area.</p><p> </p>
118

Comparative Study of Containment Strategies in Solaris and Security Enhanced Linux

Eriksson, Magnus, Palmroos, Staffan January 2007 (has links)
<p>To minimize the damage in the event of a security breach it is desirable to limit the privileges of remotely available services to the bare minimum and to isolate the individual services from the rest of the operating system. To achieve this there is a number of different containment strategies and process privilege security models that may be used. Two of these mechanisms are Solaris Containers (a.k.a. Solaris Zones) and Type Enforcement, as implemented in the Fedora distribution of Security Enhanced Linux (SELinux). This thesis compares how these technologies can be used to isolate a single service in the operating system.</p><p>As these two technologies differ significantly we have examined how the isolation effect can be achieved in two separate experiments. In the Solaris experiments we show how the footprint of the installed zone can be reduced and how to minimize the runtime overhead associated with the zone. To demonstrate SELinux we create a deliberately flawed network daemon and show how this can be isolated by writing a SELinux policy.</p><p>We demonstrate how both technologies can be used to achieve isolation for a single service. Differences between the two technologies become apparent when trying to run multiple instances of the same service where the SELinux implementation suffers from lack of namespace isolation. When using zones the administration work is the same regardless of the services running in the zone whereas SELinux requires a separate policy for each service. If a policy is not available from the operating system vendor the administrator needs to be familiar with the SELinux policy framework and create the policy from scratch. The overhead of the technologies is small and is not a critical factor for the scalability of a system using them.</p>
119

Placering av lastbärare : Faktorer som styr placeringen av lastbärare i terminal

Sahlin, Sofia January 2009 (has links)
Purpose: The Essay is written on behalf of a company called ”Uppdragsgivaren”. The purpose is to connect theory with the result of the survey and thereby find the critical factors for an optimal placement of the cargo holders in the company’s terminal.       Method: A qualitative case study has been carried out. The theory collection is completed with the result from the survey, which include the information “Uppdragsgivaren“ provides and the result from the survey. The survey is completed with telephone interviews. The survey is sent to seven persons working on similar company as “Uppdragsgivaren”. The study has a combination between the positivistic and hermeneutic view. The result is treated deductive. Theory and empirical are connected and among several theories one is chosen and will be tested on the company. Recommendations are given to “Uppdragsgivaren” and so are suggestions on further studies.   Result: The test shows that one part of the model is possible for “Uppdragsgivaren” to use when they want to optimize the cargo holder terminal. Part one of the tested model is independent from frequency and volume, and is therefore not applicable. Part two is applicable and the cargo holders can be arranged based on their volume. The result is thus that the most frequent cargo holder shall be placed on the most accessible area.
120

Producer Responsibility Scheme: management ofpost-consumer beverage containers in Hong Kong

Choi, Fuk-sing., 蔡福星. January 2007 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

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