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86 Uppsatser om Marine propulsion - Sida 1 av 6

När ska dieselelektrisk framdrift av fartyg väljas?

Diesel electric propulsion is in many ways a good alternative to conventional shaft propulsion, both economically and environmentally. There are also many other good side effects which need to be considered, i.e. better manoeuvrability, more efficient use of space and less noise on board. However, there are applications where diesel electric propulsion is not profitable. Large ocean going ships? profitability is much depending on fuel costs and the diesel electric alternative cannot compete on long journeys with large low speed engines.This thesis will treat the aspects of choosing between a diesel electric system and a classic mechanical propulsion system.

Upprorsbekämpning i Anbar-provinsen

During 2004 to 2008, The United States Marine Corps (USMC) executed counterinsurgency operations in Anbar Province with the purpose to stabilize one of the most violent areas in Iraq. The Marine Corps successfully managed to suppress the insurgency as violence dropped dramatically in late 2007. What did the marines do in order to suppress the insurgency? Why did violence drop in the province? The Marine Corps approach and procedures have been examined earlier through theories of organizational learning and adaptation. However, there is an absence of studies aiming to analyse the Marine Corps? counterinsurgency approach through the analytical lens of counterinsurgency theory.

Marschen mot Bagdad : 1st Marine Division

Denna uppsats avhandlar 1st Marine Division och deras väg in i Irak under operation Iraqi Freedom. Syftet med uppsatsen är att verifiera om det var konceptet manöverkrigföring som 1st Marine Division använde sig av under invasionen? Det har sagts att amerikanerna använde sig av manöverkrigföring i denna operation. Jag ställer mig mer frågande om det verkligen var det konceptet som de använde sig av.För att svara på frågeställningen har jag först beskrivit vad manöverkrigföring är, därefter har jag gjort en fallstudie på 1st Marine Division och deras agerande under invasionen av Irak 2003. Vi följer divisionen från utgångsgrupperingen i Kuwait tills divisionen är inne i Bagdad.

Nya gränssnitt mellan människa och hav: interaktiva teknologier för ett marint upplevelsecenter.

This thesis project explores technologies that enable people to experience the world through animals' senses in order to spark interest in and awareness about the marine environment and its inhabitants. The project is carried out as part of a planned ocean themed science center. The purpose is to explore how a greater understanding of the marine environment can be achieved using interactive technologies. The thesis is based on a theoretical framework consisting of academic works on experience, learning in a museum context and sensory perception. Our proposed designs are a series of, primarily, wearable devices that translate sensory experiences and principles from the marine world to humans.

Analys av passiva kylningsmetoder vid tillämpning över en hotspot genom analytiska och numeriska simuleringar : Till vilken grad kan passiva kylningsmetoder tillgodose ett lokalt kylningsbehov i ett marint framdrivningssystem?

I ett marint framdrivningssystem byggt av Rolls-Royce Marine i Kristinehamn, kallat POD Propulsion - MermaidTM, kyls systemets yttre delar med fo?rbistro?mmande vatten. Det kylande vattnet kompletteras av ett internt luftkylningssystem vilket, till fo?ljd av en la?gre kylningskapacitet a?n fo?r det externa vattnet, fo?rorsakar en otillra?cklig kylning i den sektor av elmotorns stator vars periferi kyls av kylluftsstro?mmen. En andel av statorn a?r sa?ledes enbart luftkyld vilket medfo?r att den axiella temperaturen i denna sektor uppna?r ett lokalt maximum, kallad ?hotspot?, vilken a?r ho?gre a?n fo?r resten av elmotorns stator.Avsaknaden av en tangentiellt uniform temperatur i statorn medfo?r begra?nsningar vid dimensionering av framdrivningssystemet.

Isolating microorganisms from marine and marine-associated samples : a targeted search for novel natural antibiotics

The search for antibiotic compounds from the natural environment has been going on for seven decades, ever since penicillin entered the market and antibiotic treatments became routine. The evolutionary pressure put on the pathogenic microorganisms induced a rapid spreading of naturally occurring resistance genes, leaving only the option of finding new antibiotics to treat the resistant pathogens. Microorganisms have been extensively mined for their biosynthetic abilities to produce biologically active compounds. To date, more than 23 000 microbial natural products have been discovered. The Actinomycetales are ubiquitous bacteria that have been used for antibiotic discovery for more than half a century, and over 10 000 natural products have been identified from the order.

Nanostrukturell ytbeläggning på utsatta delar av marina drivlinor

Nowadays naval units are participating in international missions, where new and in many cases tougher conditions will affect their propulsion. This essay deals with some of the now developed nanostructure coatings and gives a presentation of how the coatings could function on some exposed parts of the naval powertrain. The essay investigates the possibility that the coatings can be used as a protective layer that will reduce or prevent wear on selected parts of the naval powertrains. As a basis for the essay, nanotechnology is described, as well as different reasons that wear occurs and application techniques for coatings The conclusion is that nanostructured coatings can be applied and provide a much better result on hardness and wear resistance as of naval powertrains compared to micro-structural coatings, both for manufacturing and renovation. The essay presents a few examples of the military utility of the nanostructure coatings as well as suggestions for further research..

Hav och Strand : stenteknologi och marin anpassning på Gotland under Senboreal/Tidigatlantisk tid

The essay circulates around the technological analysis of flint material from four localities around the Baltic Sea basin. The analysis was created to investigate the question of where the first Gotlandic settlers originated from and to give clues about the colonization process. The investigated material was collected during the fall of 2011 and a correspondence analysis is used to analyze the collected material. The purpose of using a correspondence analysis is to test the method as a tool for investigating Mesolithic flint technologies. The essay also discusses marine hunter-gatherers, their economy and how their archeological remains differ from terrestrial hunter-gatherers..

Hur biodiversitet på ekosystemnivå skiljer sig mellan olika habitat

Biodiversity can be described as the total variation of life forms, where diversity ranges from gene level up to the ecosystem level. The diversity can be calculated in a number of ways, and this study use one of these methods. In this study empirical food webs have been used and analyzed, where eleven characters are defined and used as parameters to calculate the Euclidean distances between food webs that describe the variation that may exist within classes of terrestrial, marine and freshwater habitats. The class who stood out and showed the greatest diversity at the ecosystem level was the marine food webs, which showed a high value of the average euclidean distance. The other networks were not as distinctive and the average of the euclidean distance in these classes was comparatively low..

Konceptstudie av eltransmission för 8-hjulsdrivet fordon

SEP Modular Armoured Tactical System is the next generation of military vehicles developedby BAE Systems Hägglunds AB. At present time, BAE Systems Hägglunds AB aredeveloping a 6-wheel electrical hybrid and a conventional 8-wheel vehicle. The questionformulation was summarized as: ?In which ways can the electrical transmission in a hybriddriveline for SEP be designed, when the surrounding fixed interfaces are kept and the unity ofcomponents within SEP is maximized??. The purpose of this master thesis was to study avariety of concepts for hybrid propulsion.

Vindkraft och elbilar på Öland år 2020 : Är smart laddning av elbilar lösningen på ett framtida flaskhalsproblem?

The Island of Öland has one of the best wind climates for land based wind power in Sweden. An objective for the Island is to become self sufficient using electricity from renewable source of energy such as wind. There is currently 55 MW capacity installed on the Island and it is estimated that grid congestion will occasionally occur if more than 135 MW was installed.The aim of this thesis is to investigate he possibilities for load management by smart charging of electric vehicles, EV. The definition of smart charging is that the charging is done to some extent with an ICT-system, (information and communication technology) that correlates wind electricity generation to the charging of electric vehicles. The purpose is to avoid grid congestions on the sub-sea cable that connects Öland to the mainland because that in turn would curtail wind energy production.

Omvärldsanalys i olika typer av organisationer. En jämförande studie av omvärldsanalysen i en kommun och ett företag.

This master thesis deals with the differences in the design of the environmental scanning between different kinds of organisations, as well as the demands and regulations etc. in the respective environments that influence the environmental scanning. The content of the environmental scanning and the organisation of the function are outside the scope of this study. Two organisations that do not have an organised function but are scanning their environment were chosen for the investigation. A model for conducting the environmental scanning developed by Frankelius is used to analyse the practice of environmental scanning.

Konduktivitet i vattendrag som indikator på sura sulfatjordar

Increasing attention is being given to acid sulphate soils wherever they occur. The problems that leaching sulphate soils gives with significant lowerings of pH and mobilization of heavy metals influence large spectra of our society from fisheries to agriculture to construction. Mapping these soils is consequently of great importance and the methods of doing this is very much lacking in function and precision. This study was therefore carried out to investigate whether conductivity in running water can be used as a simple instrument to identify acid sulphate soils in the catchment. 31 coastal streams in the county of Västerbotten were analyzed for different catchment properties such as occurence of marine sediments and basic water chemistry including conductivity and sulphate.

En korporativ sjöfartspolitisk utkik? : En fallstudie av tillkomsten av TAP-avtalet, och skapandet av en globalt anpassad marknad.

The thesis examines the crisis that the Swedish-flagged merchant marine underwent in the 1990s, that resulted in a narrow market for the Swedish-flagged fleet. In order to save the industry, the TAP- agreement was created, consisting of three parties, government- market and interest organizations.  Purpose in this thesis, is to exam how the TAP-agreement was carried out in relation to the parties, and how it correlates in relation to how the global political economy affected the Swedish maritime politics. Two questions are presented. Is the TAP agreement an expression of Swedish corporatism?  Which aspect of Global Political Economy is characteristic for the TAP agreement? A case study is preformed in three steps. The different parties of the TAP-agreement have been interviewed.  A comparative study of two Swedish crises has been performed, in order to establish the correlation between them, in regards to corporatism.  A survey, with the aim to pinpoint which aspect of Global Political Economy is characteristic of the TAP agreement. Findings in this thesis are that the TAP-agreement was designed through corporatism, and that the most important aspect of all, the Swedish flag was worth saving, for all parties. .

Säkerhetsegenskaper hos en rymdreaktor

A Monte Carlo simulation of the ELECTRA reactor using (U,Zr)N fuel and a liquid lithium coolant is performed using the Serpent simulation code. The results show a reactor with a total reactivity coefficient of the coolant, fuel and material expansion that is strongly negative. These properties make the ELECTRA reactor a good candidate for a safe space reactor that could be used for propulsion of manned and unmanned space vehicles to Mars and other parts of our solar system..

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