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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.
21

La toxoplasmose chez les Inuits : investigation de l'écologie de toxoplasma gondii dans l'Arctique canadien

Simon, Audrey 04 1900 (has links)
No description available.
22

Desenvolvimento de um modelo matemático para minimização do custo total da operação de transporte de petróleo via marítima.

PUCU, Paulo Aliberto Barros. 20 April 2018 (has links)
Submitted by Jesiel Ferreira Gomes (jesielgomes@ufcg.edu.br) on 2018-04-20T20:05:55Z No. of bitstreams: 1 Paulo Aliberto Barros PUCU – TESE (PPGEQ) 2015.pdf: 1544520 bytes, checksum: 9f0c94dbee5a50446ebe3c2ab8e538a5 (MD5) / Made available in DSpace on 2018-04-20T20:05:55Z (GMT). No. of bitstreams: 1 Paulo Aliberto Barros PUCU – TESE (PPGEQ) 2015.pdf: 1544520 bytes, checksum: 9f0c94dbee5a50446ebe3c2ab8e538a5 (MD5) Previous issue date: 2015-02-24 / O Brasil possui atualmente 115 plataformas de petróleo, sendo 79 fixas e 34 flutuantes, com capacidade de produção de 2,1 milhões de barris diários de petróleo. Diante desta produção torna-se necessária uma estratégia eficiente para a distribuição deste petróleo para as refinarias, onde será processado e refinado. O petróleo proveniente das plataformas é transportado para as refinarias através de navios ou dutos, sendo que grande parte do custo operacional de produção é devido ao seu transporte. Por este motivo a minimização do custo de transporte é extremamente importante. Este trabalho tem por objetivo, utilizando a técnica de programação matemática (Programação Linear Inteira Mista – PLIM), reduzir os custos decorrentes do sistema de transporte. O modelo consiste em uma frota heterogênea de navios, os quais apresentam compartimentos que só podem ser ocupados por um único tipo de produto em cada viagem. Inicialmente são geradas todas as possíveis rotas e, posteriormente, selecionados os navios, associados às respectivas rotas, de forma a atender as demandas das refinarias e a necessidade de retirada de petróleo dos tanques de armazenamento das plataformas. Para a implementação do modelo foi utilizado o software GAMS (General Algebraic Modeling System), juntamente com os solveres de otimização CPLEX e BONMIN. / Currently, Brazil has 115 petroleum platforms, been 79 fixed and 34 floating, with daily production capacity of 2.1 million barrels of oil. Given this production is necessary a strategy for the efficient distribution of oil to refineries, where it will be processed and refined. Oil from the platforms is transported to refineries through pipelines or ships, with much of the operational cost of production is due to transport. For this reason the minimization of the cost of transport is extremely important. This work has for objective, using the technique of mathematical programming (linear mixed integer programming - LMIP), reduce costs arising from transport system. The model consists of a heterogeneous fleet of ships, which have compartments that can only be occupied by a single type of product on each trip. Initially are generated all possible routes and then selected the vessels, associated with their routes in order to attend the demand of refineries and the need for removal of oil in the storage tanks of the platforms. For the implementation of the model was used the software GAMS (General Algebraic Modeling System), together with the solveres of CPLEX and BONMIN optimization. The results were satisfactory.
23

Přeprava výrobků firmy Česká zbrojovka a s. / Transportation of products of Česká zbrojovka a.s.

Gromanová, Monika January 2013 (has links)
The diploma thesis deals with the issue of international transportation of products traded by Česká zbrojovka a.s., concentrating specifically on air and sea transportation. The main focus is on the transport of products destined for the automotive industry and on the transport of weapons and cartridges. The first theoretical part deals with air and sea transport, transport of dangerous goods and the International Commercial Terms (INCOTERMS). The second practical part examines separate transports of these products. In the end of this practical part are these concrete examined transports compared.
24

Kan inrikessjöfarten vara en del i att nå Sveriges klimatmål? : -En fallstudie i olika transportsätts miljöpåverkan / Domestic sea transport a part in reaching Sweden’s climate goals? : -A case study in the environmental impact of different modes of transport.

Furehed, Gustav, Lanfelt, Patrik January 2020 (has links)
Arbetet med att minska människans utsläpp av växthusgaser är en fråga som är högaktuell idag. Transportsektorn är den sektor som har näst störst klimatpåverkan inom EU-området. För att minska transportsektorns klimatpåverkan anser EU-kommissionen att en del av det gods som idag går på väg behöver flyttas till tåg eller sjö för att nå EU:s miljömål. Syftet med arbetet var att undersöka skillnaden av växthusgasutsläpp för transport av containrar beroende på transportsätt på sträckan Göteborg till Stockholm. De undersökta transportsätten var lastbil, godståg och containerfartyg. Studien använde en empirisk fallstudie där växthusgasutsläpp beräknades utifrån empiriska bränsleförbruknings data. Fallstudien kompletterades med en intervju från en person med stor erfarenhet av godstransporter på sträckan. Resultatet av undersökningen är att järnvägens miljöverkan är minst, men för tidskänsligt gods är fortfarande vägtransport det effektivaste transportslaget. För att sjöfart ska vara ett miljömässigt alternativ måste anpassningar av fartyg och/eller drift göras. / The work to reduce greenhouse emissions created by humans is a question that is highly relevant today. The transport sector is the second largest emitter of greenhouse gases in the European Union. To reduce the greenhouse emissions from the transport sector the EU commission has said that some of the freight that currently is being transported by road must move to rail or sea transport in order to reach EU environmental targets. The scope of this study is to compare the greenhouse emissions based on fuel consumption from domestic container transport between Gothenburg and Stockholm. The different modes of transports studied were trucks, freight train and container ship. The study was conducted using an empirical case study to calculate the greenhouse gas emissions using empirical fuel consumption data. The case study was supplemented by an interview with a person with great insight in the transport business. The result from the study shows that from an environmental perspective container transport by rail should be used. Transport by road is still the best means of transport for time sensitive cargo. If transport by sea is to be an environmental option, there has to be adjustments on either ships or management or both.
25

Prospects for continued use and production of Swedish biogas in relation to current market transformations in public transport / Utsikter för fortsatt användning och produktion av svensk biogas i förhållande till pågående marknadsförändringar inom kollektivtrafiken

Hagstroem, Agnes January 2019 (has links)
Biogas is largely utilised as vehicle fuel in public bus transport in Sweden today. This study investigates opportunities and barriers for continued domestic use and production of biogas, in relation to the ongoing electrification of public bus transport. The analysis is based on interviews with actors in public transport and the biogas sector, experts on biogas systems, and representatives for alternative user segments. Three regions were chosen as case-studies for investigations of prospects in public transport, i.e. Stockholm, Västra Götaland and Skåne, though alternative uses were studied from a national perspective. In addition to public transport, considered uses include road transport, sea transport, industries, and electricity and heat production. The study identifies a broad agreement among stakeholders that renewable resources should be implemented where they provide most benefits from a system perspective. Therefore, electric public buses are valued in urban environments, while biogas solutions are found suitable for regional routes. Biogas is further viewed as environmentally beneficial in all user segments except continuous electricity and heat production, where it largely would replace renewable rather than fossil sources. Regarding costs and competitiveness, probable future uses are identified within light and heavy-duty road transport, and in consumer-oriented industries, i.e. the food industry. Economic support in policy instruments is further considered essential for continuous development of the Swedish biogas sector, though current influential instruments, e.g. the tax exemption, are described as short-term and unpredictable. The willingness to pay for the collected societal benefits of biogas further decrease in transitions from public to private consumers, and as biogas solutions simultaneously are linked with limited or uncertain competitiveness in these sectors, risks prevail that such transitions could imply stagnations and declines in biogas use and production, given today’s situation. / Idag används biogas till stor del som drivmedel för bussar inom kollektivtrafik i Sverige. Denna studie undersöker möjligheter och hinder för en fortsatt nationell användning och produktion av biogas, i samband med att bussar inom kollektivtrafiken nu elektrifieras. Analysen är baserad på intervjuer med aktörer inom kollektivtrafiken och biogassektorn, sakkunniga inom biogas, och alternativa användare av biogas. Tre regioner, Stockholm, Västra Götaland och Skåne, valdes som fallstudier för analys av möjligheter för fortsatt användning inom kollektivtrafiken. Alternativa användningar studerades istället ur ett nationellt perspektiv, och inkluderade vägtransporter, sjöfart, industri och el- och värmeproduktion. Studien visar att det råder enighet mellan intervjupersoner att förnybara resurser över lag ska användas där de medför störst samhällsnytta sett till samhället i stort. Inom kollektivtrafiken beskrivs elbussar därför som fördelaktiga i stadsmiljöer, medan biogas ses som lämpligt i regional trafik. Biogas framställs dessutom som miljömässigt fördelaktigt i alla alternativa användningsområden utom kontinuerlig el- och värmeproduktion, eftersom då främst förnybara och inte fossila resurser ersätts. Med hänsyn till kostnader och konkurrenskraft ses lätta och tunga transporter tillsammans med kundnära industrier, t.ex. livsmedelsindustrin, som troliga framtida användningsområden för biogas. Ekonomiskt stöd från styrmedel bedöms vara nödvändigt för en fortsatt utveckling av biogassektorn i Sverige, även om dagens styrmedel, t.ex. skattebefrielsen, beskrivs som kortsiktiga och oförutsägbara. Betalningsviljan för biogasens samlade samhällsnyttor minskar också vid en övergång från offentliga till privata kunder. Eftersom biogas därtill har en begränsad eller osäker konkurrenskraft jämtemot andra alternativ i de privata segmenten, identifierar denna studie risker för stagnation eller nedgång i användning och produktion av biogas vid en eventuell utfasning från den offentliga sektorn, givet dagens situation.
26

[en] SELECTION OF SHIPPING FREIGHT OPTIONS FOR EXPORT AND IMPORT OF CRUDE OIL AND DERIVATIVES: PROPOSAL OF A MULTICRITERIA MODEL WITHIN THE NEW PARADIGM OF INTERNATIONAL MARITIME TRANSPORT / [pt] SELEÇÃO DE OPÇÕES DE AFRETAMENTO DE NAVIOS PARA EXPORTAÇÃO E IMPORTAÇÃO DE PETRÓLEO E DERIVADOS: PROPOSTA DE UM MODELO MULTICRITÉRIO SEGUNDO O NOVO PARADIGMA DO TRANSPORTE MARÍTIMO INTERNACIONAL

MARCOS ALEXANDRE TAVARES DOS SANTOS 02 August 2022 (has links)
[pt] O objetivo desta dissertação é desenvolver e demonstrar a aplicabilidade de um modelo multicritério para a seleção de opções de afretamento de navios para exportação e importação de petróleo e derivados, segundo dois vetores de transformação do transporte marítimo internacional – Shipping 4.0 e Green Shipping. A pesquisa pode ser considerada aplicada, descritiva e metodológica. Quanto aos meios de investigação, a metodologia compreende: (i) pesquisa bibliográfica e documental sobre os temas centrais da pesquisa; (ii) caracterização das principais tecnologias digitais embarcadas e sistemas inteligentes que vêm sendo empregados na indústria naval, associando-as a requisitos funcionais e operacionais de navios inteligentes e sustentáveis; (iii) análise morfológica para concepção de configurações alternativas de navios inteligentes e sustentáveis; (iv) desenvolvimento de modelo multicritério para seleção de opções de afretamento de navios inteligentes e sustentáveis no contexto de exportação e importação de petróleo e derivados; e (v) demonstração da aplicabilidade do modelo conceitual, mediante a realização de um estudo empírico em uma empresa de transporte marítimo, subsidiária da Petrobras – a Transpetro. Destaca-se como resultado principal um modelo multicritério inovador para seleção de opções de afretamento de navios para exportação e importação de petróleo e derivados, que emprega análise morfológica para a geração das configurações alternativas de navios inteligentes e sustentáveis e um método multicritério de apoio à decisão para a seleção propriamente dita das alternativas de afretamento, segundo uma visão conjunta dos dois vetores de transformação do transporte marítimo internacional. O estudo empírico desenvolvido da Transpetro permitiu demonstrar a aplicabilidade do modelo em um contexto organizacional real e evidenciar seu potencial de replicação em outras empresas de transporte marítimo no Brasil e no mundo que desejam operar com novos modelos de negócio, segundo o novo paradigma de transporte marítimo internacional. / [en] This dissertation aims to develop and demonstrate the applicability of a multicriteria model for the selection of shipping freight options for export and import of crude oil and derivatives, aligned to the new paradigm of international maritime transport driven by two vectors of transformation - Shipping 4.0 and Green Shipping. The research can be considered applied, descriptive and methodological. The methodology comprised: (i) bibliographic and documental analysis on the central themes of the research; (ii) characterization of the key enabling digital technologies that have been used in the shipping industry, associating them with the functional and operational requirements of intelligent and sustainable ships; (iii) morphological analysis to design alternative configurations of shipping freight options for exporting and importing of oil and derivatives; (iv) development of a multicriteria model for the selection of shipping freight options for exporting and importing oil and derivatives, according to the new paradigm of international maritime transport; and (v) empirical study carried out in a maritime transport company, a subsidiary of Petrobras – Transpetro. The main result of this research is an innovative multicriteria model for the selection of shipping freight options for exporting and importing oil and derivatives, which integrates morphological analysis with a multicriteria approach for selecting shipping freight options, aligned to a joint vision of shipping 4.0 and green shipping. Furthermore, the empirical study developed at Transpetro made it possible to demonstrate the applicability of the model in a corporate context and to highlight its potential for replication in other maritime transport companies in Brazil and in the world, which wish to operate according to new business models in the new paradigm of international maritime transport.
27

Les grands navires construits à clin en Europe septentrionale et occidentale du milieu du 14ème au milieu du 16ème siècle / The large clinker ships in Northern and Western Europe from the mid-14th to the mid-16th century

Grille, Alexandra 05 July 2016 (has links)
Depuis les années 1980, des épaves de grands navires construits à clin de la fin du Moyen-Age ont été découvertes sur les littoraux des mers septentrionales et occidentales. Elles ont régulièrement suscité individuellement un intérêt de la communauté scientifique en regard de leur architecture, puisque la fin du Moyen-Age correspond historiquement à l’apparition puis à la diffusion et à l’adaptation de la construction navale à franc-bord d’origine méditerranéenne en Europe du Nord et de l’Ouest. Pourtant, la comparaison des différentes épaves entre elles pour étudier les développements de la construction navale à clin de cette période est très récente et généralement rattachée à l’analyse des épaves nouvellement trouvées.Cette thèse étudie l’ensemble des navires de plus de 20 m de long susceptibles, par leur architecture, d’avoir évolué en haute mer sur les routes du commerce lointain. En regard du contexte technique et historique, cette étude est limitée géographiquement aux mers nordiques et chronologiquement au Moyen-Age tardif et au début de la période moderne.Le navire résulte à la fois des technique de construction navale et de la demande de ses commanditaires. Durant la période d’étude envisagée dans la thèse, les marchands, qui sont également les affréteurs, constituent les principaux armateurs avec les gens de mer, marins et capitaines, qui régulièrement sont propriétaires en totalité ou en partie des grands bâtiments.De ce fait, le contexte historique, affectant les activités de commerce et de transport, contribue à expliquer les développements de la construction navale. De plus, l’analyse technique des épaves permet de comprendre comment les charpentiers de marine ont pu répondre à la demande de ces propriétaires. Pour cela, la reconstitution des épaves, comme celle de l’Aber Wrac’h 1(France), est essentielle, car les données relatives à la construction, la conception et la forme des navires fournissent des éléments de comparaison scientifique fiables en regard des typologies chronologiques et régionales et permettent de replacer le navire dans son contexte historique et socio-économique. / Since the 1980s, several wrecks of large clinker ships adting from the late Middle Ages were found on the coasts of Northern and Atlantic seas. The scientific community was regularly interested in the architecture of each site as the late Middle Ages historically corresponds to the appearance, dissemination and adaptation of the carvel shipbuilding from the Mediterranean in Northern and Western Europe. Yet the comparison of the different wrecks themselves to study the development of the clinker shipbuilding of this period is recent and usually linked to the analysis of newly found wrecks.This thesis explores all vessels over a length of 20 meters, which were able, according to their architecture, to sail on open seas for long-distance trade. Due to the technical and historical context, this study is limited geographically to the nordic seas and chronologically to the Late Middle Ages and early modern period.The ship results from the shipbuilding technology and the demand of its owners. During the late Middle Ages, the merchant class, which was the principal user, was also the main shipowner with the seafarers, sailors and captains, who regularly owned all or part of large vessels.Therefore, the historical context, affecting trade and transport activities, helps to explain the developments in shipbuilding. Therefore, technical analysis of wrecks allows understanding how the shipwrights and carpenters could meet the demand of those owners. Hence, there construction of the wreck, such as Aber Wrac’h 1 (France), is essential because the data about the building, design and shape of the vessels provide reliable scientific information for comparison in terms of chronological and regional typologies and help to place the ship in its historical, environmental and socio-economic context.

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