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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

Particulate trace metals in British coastal waters

Williams, Mark Richard January 1995 (has links)
Key processes affecting the transport of particulate trace metals in the coastal waters of the Irish and North Seas have been examined. Sample collection and experimentation was carried out on board R.R-S. Challenger in January 1992 (Irish Sea) and in December 1992 and November 1993 (North Sea). Particulate samples were digested in IM HCI and the concentrations of Ca, Cd, Co, Cu, Fe, Mn, Pb and Zn were determined, together with the 206/207Pb isotopic ratio. In the North Eastern Irish Sea the concentrations of suspended particulate trace metals were affected significantly by tidal processes, such that ebb tides transport particles of higher trace metal concentrations from the nearshore, while flood tides transport metal-depleted particles from offshore. This tidally-induced transport was confirmed by complementary 206/207Pb analyses, which showed the value of this technique in particle tracing. In the North Sea suspended particulate trace metal concentrations were higher adjacent to industrialised estuaries and high Pb concentrations were found m the Tyne/Tees region (in the range 200 - 340 ug g-1), in combination with low 206/207Pb suggesting an anthropogenic origin. Estimated fluxes of trace metals from the Humber Estuary to the North Sea were relatively small compared to the PARCOM inputs to the estuary. There was little evidence of interannual variability in these fluxes compared to those obtained in December 1988. Samples of end-members of the Humber Plume particle mixing series (estuary and cliffs) were used in radiochemical uptake studies, which indicated a response time of about 1 day for 109Cd, 137Cs and 65Zn to reach a new equihbrium. When the end-members were mixed together in various proportions they showed the uptake of 109Cd and 54Mn behaved non-additively. Settling of suspended particulate trace metals in the plume region was examined in unique experiments involving stable and radioisotopes. It was shown that trace metals were preferentially associated with different settling fractions. Lead was associated with slow settling particles whereas Cu was associated with particles settling more rapidly. The results presented in this dissertation allowed the development of a conceptual model for fine sediment transport for trace metals, which could be interfaced with established hydrodynamic models.
2

Market contestability and shipping

Howson, Michael January 2002 (has links)
No description available.
3

[en] INFORMATION QUALITY IMPROVE ON PETROBRAS MARITIME TRANSPORT: ANALYSIS AND PROPOSALS / [pt] MELHORIA DA QUALIDADE DA INFORMAÇÃO NO TRANSPORTE MARÍTIMO DA PETROBRAS: ANÁLISE E PROPOSIÇÕES

EDUARDO LADEIRA AVILA 22 October 2008 (has links)
[pt] Para uma empresa como a Petrobras o transporte marítimo tem grande importância nas suas operações logísticas de suprimento dos mercados nacional e internacional. As informações geradas por esse modal são utilizadas na coordenação do planejamento e o controle das operações, por isso a necessidade de garantir a sua qualidade. Esse trabalho apresenta uma aplicação prática dos conceitos da Engenharia de Processos e do Processo de Pensamento da Teoria das Restrições através de um estudo de caso cujo foco é o fluxo de informações no transporte marítimo. O objetivo é apresentar O quê mudar, Para o quê mudar e Como mudar a realidade desta empresa e melhorar o desempenho de seus processos. / [en] For a company like Petrobras, the marine transportation has a great importance in its supply logistic operations for national and international markets. The information generated for this modal are used in the planning coordination and the control operations, so that, there is the necessity of guarantee its quality. The work presents a practical application of the concepts of Processes Engineering and the Theory of Constrains Thinking Process through a case study with focus on information flow of the maritime transport. The objective is present what to change, what t change to and how to change the reality of this company and to improve the its processes performance.
4

[en] ANALYSIS OF THE FACTORS THAT INFLUENCES THE LIQUID BULK MARITIME TRANSPORTATIONS FREIGHT RATE IN THE SPOT MARKET / [pt] ANÁLISE DOS FATORES QUE INFLUENCIAM O FRETE NO TRANSPORTE MARÍTIMO DE PETROLEIROS NO MERCADO SPOT

CELIO WAKAMATSU 12 November 2008 (has links)
[pt] O presente trabalho apresenta uma análise dos fatores que influenciam o valor de frete no transporte marítimo de petróleo e seus derivados, no mercado spot de curto prazo. A análise levará em conta fatores específicos da indústria, como por exemplo estoques de petróleo nos Estados Unidos, preço de compra de navio, bem como fatores mais genéricos, como temperatura, PIB, taxas de câmbio, entre outros. Embora a parcela de frete seja relativamente pequena em relação ao preço do produto transportado (varia usualmente entre 3% e 10%), ele é fator decisivo na composição da margem de lucro. Muitas vezes seu preço faz a diferença entre um negócio ser lucrativo ou não, pelo fato das margens de negociação de petróleo e seus derivados serem bastante restritas devido à forte competição. Entender como se comporta esse mercado é de grande utilidade para as empresas participantes desse mercado. A atividade de afretamento é responsável por grande parte dos custos logísticos das empresas da indústria, logo uma melhor performance nessa atividade certamente trará resultados sensivelmente positivos ao resultado global dessas empresas. / [en] This dissertation presents an analysis of the variables that influence the freight rate of the maritime transportation industry of liquid bulk cargoes, on the spot market in the short term. This analysis will consider both the specific variables of the industry, such as crude oil inventories in United States, price of a vessel, as well as generic variables, such as temperatures, GDP, exchange rates, among others. Although the freight rates usually have small participation comparing with the product`s price (often between 3% and 10%), it is very important when considering profits. Frequently the freight rate will make the whole difference, and will tell if the business was profitable or not, because margins in the crude oil and derivates trade are very tight, due to the strong competition. Understanding how this industry works is of great value for the players of this market. Chartering is responsible for a big share of the logistical costs of oil companies, thus a better performance of this activity will surely bring better global results for them.
5

[en] THE PORT OF SALVADOR: ANALYSIS OF THE CURRENT REALITY, ITS NECESSITIES AND COMPARISONS AFTER LAW 8.630/93 / [pt] O PORTO DE SALVADOR: ANÁLISE DA REALIDADE ATUAL, SUAS NECESSIDADES E COMPARAÇÕES PÓS LEI 8.630/93

ANTONIO DE BIASO JUNIOR 08 January 2007 (has links)
[pt] O trabalho em questão possui como principal objetivo fazer uma análise completa da atual situação portuária de um dos principais portos da região nordeste do Brasil, desde a implantação da lei 8.630 de 25 de fevereiro de 1993, conhecida como lei de modernização dos portos, até os dias atuais. Faz uma análise do porto, da lei 8.630 e da infra-estrutura existente nas áreas públicas e privadas, assim como de seus equipamentos de movimentação de carga, custos portuários diretos e/ou indiretos e gargalos logísticos, que influenciam os fretes marítimos, forçando, muito das vezes, a saída de clientes para outros portos da região. Apresenta os operadores portuários e o terminal de contêineres, comparando sua produtividade e seu desempenho operacional antes e depois da privatização. Faz referência ao programa de revitalização da área portuária e as futuras melhorias. O trabalho, também, apresenta comparações de produtividade e custos, entre o porto de Salvador e outros portos nacionais e internacionais, na tentativa de mostrar sua posição atual dentro do cenário nacional e da intenção em vir a ser um porto concentrador de carga da região. / [en] The follow document has the main objective to make a complete analysis of the current port situation of the main port of the Brazilian northeast region, since the implementation of the law 8.630 dated of February, 25th, 1993, known as the law of modernization of the ports, until the current days. It makes a analysis of the port, the law 8.630 and of the public and private infrastructure areas as well as its equipments of load cargoes movement, the port cost, direct and/or indirect and the existents necks of logistics, that affect the ocean freights, forcing, much of the times, the exit of customers for other ports of the region. It also presents the port operators companies and terminal of containers with comparisons of its productivity and operational performance before and after the privatization. It makes a reference of the revitalization port area program and of the future improvements. The work also presents comparisons of some important index between Port of Salvador and other nationals and internationals ports with the attempt to present the position of national scenery as well as with the intention to be a hub port of the region.
6

An examination of the application of the Sea Transport Documents Act 65 of 2000 to title to sue under contracts of carriage evidenced by sea waybills and straight bills of lading.

Donnelly, Dusty-Lee. January 2013 (has links)
The Sea Transport Documents Act, 65 of 2000, was a remedial statute intended to provide a solution to the problem of title to sue under the contract of carriage evidenced by sea transport documents. At common law a contract of carriage is not transferable. The contract of carriage is ordinarily concluded between the shipper and the carrier. The consignee lacks title to sue yet in terms of international sale contracts on C.I.F and F.O.B terms the consignee would be the person who stood to suffer the loss as risk in the goods passes from seller to buyer when the goods are loaded on board at the port of shipment. The Act provides a mechanism to transfer the contractual rights and liabilities with the transfer of the sea transport document. However section 2(2) restricts the application of the relevant provisions to documents that are ‘transferable or negotiable’. By custom of merchants bills of lading made out ‘to order’, and bearer bills of lading, are transferable and negotiable. However, straight bills of lading and sea waybills are made out to a named consignee only. These modern forms of sea transport document are increasingly popular and offer many advantages to traders and ocean carriers. Yet they are both regarded as non-negotiable. The dissertation examines the interpretation of the terms ‘transferable’ and ‘negotiable’ as they came to be applied to both negotiable instruments and bills of lading, and considers current academic and judicial opinion on the meaning of these terms. The provisions of the Sea Transport Documents Act are analysed, and compared to the remedies provided in the Carriage of Goods by Sea Act, 1992 (United Kingdom), similar legislation in other commonwealth countries and the law in the United States and Europe. Finally alternative means of establishing title to sue, including the stipulatio alteri, are considered. / Theses (LL.M.)-University of KwaZulu-Natal, Durban, 2013.
7

[en] OIL AND BY-PRODUCTS TRANSPORTATION: PROBLEMS, MODELS AND ALGORITHMS / [pt] TRANSPORTE MARÍTIMO DE PETRÓLEO E DERIVADOS: PROBLEMAS, MODELOS E ALGORITMOS

PAULO FERNANDO HAMACHER 31 August 2009 (has links)
[pt] Os problemas de transporte marítimo são alvo de extensa bibliografia e constituem uma importante área de aplicação da programação matemática. Em particular, o transporte de granéis - entre os quais o petróleo e seus derivados - vem sendo estudado na Petrobrás há mais de duas décadas. Apesar dos esforços despendidos, os escopos das aplicações são ainda algo limitados e os resultados práticos relativamente escassos. O presente trabalho contribui para sistematização da área, definindo uma hierarquia de problemas de transporte marítimo, padronizando conceitos e notação e desenvolvendo modelos para cada classe de aplicação. São discutidos também alguns métodos de solução e propostos procedimentos para incrementar seus desempenhos. Dois destes métodos, designados por modelo de rotas e modelo de recobrimento, são implementados para instâncias de porte real e os resultados obtidos são analisados. / [en] Sea transportation problems have been the object of extensive literature and constitute an important area for the application of mathematical programming techniques. Bulk commodities transportation, particulary of oil and its by-products, has been studied at Petrobras for over two decades. Despite all efforts, the application scopes are still rather limeted and practical results relatively scarce. The present study contributes for a systenatization in the area, defining a hierarchy of sea transportation problems, standardizing concepts and terminology and developing models for each class of application. Some solution methods are also discussed and procedures are proposed to develop their performance. Two of these methods, named Routing model and instances and the results attained are anlysed.
8

[en] FLEET SIZING OF COASTAL SHIPPING CLEAR OIL PRODUCTS VESSELS: OPTIMIZATION MODEL PROPOSAL / [pt] DIMENSIONAMENTO DA FROTA DE NAVIOS DE DERIVADOS CLAROS PARA CABOTAGEM: PROPOSTA DE MODELO DE OTIMIZAÇÃO

ANDRÉ AUGUSTO SOARES VIEIRA 25 July 2016 (has links)
[pt] O custo de transporte marítimo representa o elemento mais importante em termos de custos logísticos para a PETROBRAS. O atendimento pleno de seu mercado de derivados de petróleo somente é possível através da manutenção de uma frota de navios próprios e contratados, que navegam e operam por toda a costa marítima brasileira, além de buscarem produtos em outros países. Neste sentido, esta dissertação propõe um modelo de programação linear inteiro misto cujo objetivo é dimensionar o tamanho da frota e o porte dos navios para o transporte de derivados claros restritos à navegação de cabotagem. O modelo proposto baseia-se em um modelo existente na literatura, e seu resultado auxiliou os programadores a definir quantos navios são realmente necessários para atender os compromissos assumidos dentro de um horizonte de planejamento pré-estabelecido. Comparando este resultado com o número de navios já contratados e disponíveis para programar, pode-se, eventualmente, liberar navios para realizar viagens de longo curso, evitando assim a contratação de navios em Voyage Charter Party para este fim, além de reduzir a sobreestadia nos períodos de baixa movimentação, quando a frota contratada torna-se superdimensionada. / [en] The shipping cost is the most important element in terms of logistic costs to PETROBRAS. The full attendance of its oil products market is possible only by maintaining a fleet of own and hired ships that sails and operate throughout the Brazilian coastline besides loading products in other countries. In this sense, this dissertation proposes a model of mixed integer linear program whose objective is to determine the coastal navigation fleet size and the type of vessels to transport clean petroleum products. The model propose is based on a previous model from the literature, and its outcome helped programmers define how many ships are actually required to meet the commitments undertaken within a pre-established planning horizon. Comparing the model s result with the actual number of vessels available for programming, one can eventually release ships to make other journeys, thus avoiding the hiring of ships in Voyage Charter Party for this last purpose. It is also possible to reduce the demurrage in periods of low movement, when the fleet contracted becomes oversized.
9

Námořní kontejnerová přeprava mezi Evropou a Dálným Východem / Sea container transport between Europe and Far East

Kubečková, Alena January 2008 (has links)
The theoretical part of the master thesis decribes sea container transport, documents used in this area, price making and impacts on the enviroment. In the practical part are discribed 5 ship-owners and their services from Far East to Europe. The most suitable service is chosen for the customer. The thesis also mentions impacts of the economical crisis to the sea transport. The last chapter is dedicated to the other kind of transports form Far East to Europe.
10

[pt] DIMENSIONAMENTO DE FROTA MARÍTIMA SOB INCERTEZA EM UMA EMPRESA BRASILEIRA DE PETRÓLEO / [en] MARITIME FLEET SIZING UNDER UNCERTAINTY IN A BRAZILIAN OIL COMPANY

DANILO BAPTISTA MAROJA 06 April 2020 (has links)
[pt] A volatilidade inerente ao mercado de fretes marítimos e as incertezas relacionadas à demanda de transportes prevista contribuem para a complexidade do problema de dimensionamento da frota. Este trabalho aborda o problema da renovação da frota marítima de uma empresa brasileira do setor de óleo e gás, para o transporte, em viagens de cabotagem e longo curso, de derivados de petróleo. Para tal, é apresentado um modelo estocástico de programação inteira-mista de dois estágios para capaz de gerar indicações de contratos de afretamento a serem realizados considerando incertezas nos níveis de mercado de fretes e na previsão de volume movimentado. O modelo é capaz de fornecer composições de frota capazes de atender as especificações do problema, contudo, para os casos analisados, a avaliação das soluções obtidas ao se considerar a incerteza mostrou potencial de ganho pouco significativo em comparação com uma modelagem similar considerando valores esperados dos parâmetros. Este trabalho evidencia uma situação em que é útil a avaliação das soluções Wait-and-See (WS) e Expected Value of Expected Solution (EEV), menos demandantes computacionalmente, para calcular o potencial ganho da solução do modelo estocástico. / [en] The inherent volatility in the maritime freight market and the uncertainties related to the expected transport demand contribute to the complexity of the fleet size and mix problem. This work addresses the problem of the maritime fleet renewal of a Brazilian oil and gas company, for the transportation, in cabotage and international voyages, of oil products. To this end, we present a two-stage stochastic mixed-integer programming model capable of giving recommendations of which chartering contracts to be performed, considering uncertainties in freight market levels and in the forecasted volume movement. The model is able to provide fleet compositions capable of meeting the problem specifications, however, in the evaluated cases, little gain potential was observed by comparing the stochastic solutions to solutions considering expected parameter values. This work highlights a situation in which the evaluation of the computationally less demanding Waitand-See (WS) and Expected Value of Expected Solution (EEV) solutions is useful to calculate the potential gain of the stochastic model solution.

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