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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

Design obojživelného obytného vozidla / Design of Amphibious Residential Car

Pavliš, Michael January 2016 (has links)
This Diploma thesis deals with the design of amphibious residential car. The product is first parsed from design, marketing and technical ways. Then on the basis of analysis is designed new design that meets the ergonomic, technical, aesthetic and psychological aspects.
22

Militärteoretiska principer för amfibieoperationer : en teoriprövande och jämförande studie med utgångspunkt i två historiska amfibieoperationer / Military theoretical principles for amphibious operations : a theory of conduct and a comparative study based on two historical amphibious operations

Anderlund, Jonas January 2011 (has links)
Det ställs stora krav på den militära organisationen vid genomförandet av en amfibieoperation. Denna uppgift är något som den svenska försvarsmaktens amfibiekår ej har förmåga till att lösa ut inom ramen för vår organisation. I framtiden ställs det krav på att den svenska amfibiekåren skall kunna vara delaktig i en multinationell expeditionär landstigningsstyrka. Sverige saknar dock doktriner och en militärteoretisk grund för amfibieoperationer. För att tillhandahålla en sådan teoretisk grund avser författaren att använda sig av den brittiska militärteorin för vad en amfibieoperation kräver. I denna uppsats analyseras två historiska amfibieoperationer i allmänhet och de brittiska militärteoretiska principerna för amfibieoperationer i synnerhet. I vilken utsträckning kan Geoffry Tills grundprinciper för amfibieoperationer, förklara utgången om amfibieoperationerna i Falklandskriget och slaget om Gallipoli (Dardaneller halvön)? I Geoffry Tills bok Seapower – A Guide for the Twenty-First Century, lyfter han fram fem grundprinciper för amfibieoperationer. Dessa principer ses som krav för ett positivt resultat för en amfibieoperations genomförande. Metoden som använts utgår ifrån en design som är en teoriprövande och jämförande studie av två fall. Det är en kvalitativ textanalys. Min slutsats är att teorin förklarar amfibieoperationers utgång, beroende av om operationen uppfyller samtliga principer eller inte uppfyller dem. Uppfylls alla principerna får vi ett positivt resultat i vår amfibieoperation och uppfylls inte alla principerna får vi ett negativt resultat i vår amfibieoperation. I denna utsträckning kan teorin förklara utgången av amfibieoperationer. / It requires a lot from the military to accomplish a amphibious operation. This task is something that the Swedish royal marines dos not have the capacity to implement. In the future the Swedish government will expect that the royal marines will be able to be included in amphibious operations alongside other nations. The writer will use the British principles for what amphibious operations require.   In this essay two historical amphibious operations will be used. To what extent can Geoffrey Till´s basic principles of amphibious operations explain the result of the Falkland Campaign and the Gallipoli operation. In Geoffrey Till´s book Seapower – A guide for the Twenty-First Century, he highlights five requirements for executing amphibious operations. The authors conclusion is that the theory holds up if all principles are met or not met. If they are met the conclusion will be that the operation will have a positive outcome. If they are not met it will be a negative outcome. To this extent the theory can explain the conclusion of amphibious operations.
23

Amfibiska hus : möjligheter och utmaningar att nyttja byggtekniken

Gradén Svedlund, Hanna January 2020 (has links)
Climate change will increase the risk of floods from storms and rising sea levels in many countries with coasts, seas and rivers. In Sweden, climate change is going to affect the intensity and frequency of precipitation which, together with rising sea levels, will result in more floods in the future. In the last few years amphibious buildings have emerged as an alternative solution to building protective infrastructure such as walls and levees around communities.  There are several different strategies for how communities can be protected against floods. Amphibious architecture is a strategy were buildings are working with nature instead of trying to force water away. Amphibious buildings have the same amenities and appearance as traditional building constructions and help residents to stop living in fear of potential flood and start living in harmony with water. The building technique is applicable globally and minimizes material damage, financial losses and mental suffering in the event of a flood. The purpose of this master thesis is to contribute to increased knowledge of amphibious buildings as a building technique by summarizing experience and knowledge from other countries and identifying opportunities and limitations for building that type of constructions in Sweden. A literature study was conducted in order to find published knowledge on the subject and to form a basis for an interview study regarding opportunities and limitations to build amphibious buildings in Sweden.  Results from the literature and interview studies indicate that one of the main opportunities of the building technique is the possibility to use more land for buildings and that amphibious buildings are adapted for future climate changes. By using an alternative strategy against floods where buildings work with the water less impacts in nature and ecosystems occur. One of the limitations of amphibious construction is the limited research on the subject. Amphibious buildings also requires low vertical water flow rates and waves. Knowledge of amphibious buildings as a building technique is low among many professionals in the construction sector and many countries’ laws are not adapted to this type of construction which makes it more difficult to build amphibious houses.  Furthermore, results indicate that amphibious buildings could be an effective solution for building in flood areas. Proposals for future studies include how amphibious buildings work in a Nordic climate. Another proposal is to investigate what is needed for amphibious buildings to become an accepted alternative solutions in Swedish flood areas. / När klimaten förändras ökar risken för översvämningar från stormar, skyfall och stigande havsnivåer i många länder. Klimatförändringar kommer påverka Sverige på flera olika sätt där en konsekvens är ökad nederbörd och stigande havsnivåer vilket kommer resultera i ökat antal översvämningar i framtiden. På senare tid har alternativa lösningar lyfts fram istället för bygga skyddande infrastruktur som exempelvis skyddsmurar runt samhällen. Det finns flera olika strategier hur samhällen kan skyddas mot översvämningar där amfibisk arkitektur är en strategi som innebär natur inte motarbetas utan byggnaden samarbetar med vattenmassorna. Byggnaderna har samma faciliteter och utseende som traditionella konstruktioner men vid en översvämning flyter huset på vattnet. Byggtekniken hjälper individer som lever inom riskzon för översvämningar att sluta leva i rädsla och börja leva i harmoni med vattnet. Byggmetoden är applicerbar globalt och har potential att minimerar materiella skador, ekonomiska förluster och psykiskt lidande för inblandade vid en eventuell översvämning. Syfte med studien är att bidra till ökad förståelse om amfibiska hus som byggnadsmetod, vilka möjligheter och begränsningar som finns för att använda sig av tekniken i Sverige, sammanställa kunskap och erfarenhet från andra länder samt vilka faktorer som påverkar utformningen. Målet är att identifiera kunskaper och erfarenheter om byggtekniken och sammanfatta dessa. En litteraturstudie genomfördes i syfte att identifiera och sammanställa redan känd kunskap inom ämnet och ta fram underlag till en intervjustudie. Intervjustudien fokuserade på möjligheter och begränsningar att bygga amfibiska hus i Sverige. Intervjustudien behandlade tre perspektiv; myndighetsperspektiv, finans- och försäkringsperspektiv samt sakfrågeperspektiv.  Resultatet från litteratur- och intervjustudien indikerar att en av de främsta möjligheterna  med byggtekniken är att mer markyta kan utnyttjas och att byggtekniken är anpassad för framtida klimatförändringar. Genom att använda sig av en alternativ strategi mot översvämningar som arbetar med vattenmassorna krävs mindre ingrepp i naturen och ekosystemet. Byggtekniken är applicerbar i många olika länder och kan anpassas efter individens ekonomiska förutsättningar.  En begränsande faktor är bristen på dokumenterad kunskap som kan försvåra användning av byggtekniken. Byggmetoden passar inte alla lokaliseringar utan det är platsen förutsättningar som styr huruvida amfibiska hus kan användas. Kunskapen om amfibiska hus är låg hos många aktörer inom byggsektorn och många länders lagstiftningar är inte anpassad för denna typ av byggteknik vilket försvårar byggandet av sådana objekt.  Förslag på framtida studier är att se över hur byggtekniken kan användas för större byggnader och hur byggtekniken påverkas av nordiskt klimatet. Ett annat förslag är vilka utredningar som krävs för att svenska myndigheter ska ta ställning till byggtekniken och godkänna anpassad bebyggelse på orter med översvämningsrisk.
24

Floating Tybee: planning and designing for rising seas

Manley, Canon Randolph 27 August 2014 (has links)
There is a statistically high probability that within this generation's lifetime, the mean sea level in the south eastern coast of the United States will rise from three to six feet above what it is today. The easiest response to this scenario and its complicated and devastating repercussions is to flee, or to put up a wall. This reaction is defending current lifestyles and cultures against the liabilities and complicated problems associated with sea level rise. This thesis asks: "How can we convert the liabilities of sea level rise into assets?" Using Tybee Island of Chatham County, Georgia as a case study, this thesis will answer this question by exploring 5 topics: 1. Understanding sea level rise 2. Understanding barrier islands of coastal Georgia and Tybee Island 3. The current Sea Level Rise Adaptation Plan for Tybee Island and Where it is Lacking 4. A new urban design strategy in planning for sea level rise on Tybee Island 5. Existing instances of aquatic and amphibious architectures and a new type of amphibious architecture for Tybee Island
25

The mid-eighteenth century navy from the perspective of Captain Thomas Burnett and his peers

McLeod, Anne Byrne January 2010 (has links)
This thesis explores the concerns of mid-eighteenth century naval captains through the careers of Captain Thomas Burnett and the cohort of thirty five officers who were posted captain in 1757 soon after the start of the Seven Years' War. A subsidiary cohort, that of the 129 lieutenants who were, like Burnett, first commissioned in 1744 is used as a control against which to measure the statistical worth of the smaller cohort. Examination of the day to day concerns of the captains has been made possible through the rich and varied resource of their letters to the Admiralty, which have hitherto been little used as a source by historians. Despite the formality of these letters not merely the concerns but also the personalities and characters of the writers are vividly conveyed. After tracing the career of Thomas Burnett this thesis examines the 1757 cohort and its progression to the rank of master and commander. At this point the correspondence with the Admiralty begins. The influences, 'interest' and formative experiences behind their appointments are considered. The duties of the mid-eighteenth century captain are outlined, as their relationship with the Admiralty is analysed and the extent to which they were kept under strict Admiralty control by precedent and financial scrutiny is demonstrated. All aspects of manning are shown to dominate the daily concerns of captains. The extent to which 'interest' or chance gave them the opportunity to display their professional expertise and increase their standing within the active naval corps is weighed. Tracking this cohort beyond the war into the years of peace and subsequent wars has revealed the extent to which the timing of being made post captain was crucial and that 'interest' was more significant than merit in accelerating and promoting active careers.
26

Analysis of current Department of Defense risk management practices in weapon system acquisition : a case study of the Advanced Amphibious Assault Vehicle (AAAV) PDRR and SDD risk management practices

Bailey, Robert O. 03 1900 (has links)
Approved for public release; distribution in unlimited. / This thesis discusses risk in Department of Defense (DoD) weapon systems acquisition. It uses the Marine Corps' Advanced Amphibious Assault Vehicle (AAAV) as a case study in risk management strategy and techniques. The AAAV will provide the Marine Corps with a fast deploying, over-the-horizon, waterborne insertion capability. The AAAV's improvements over the currently fielded Amphibious Assault Vehicle (AAV) will provide Marines with a highly survivable and lethal weapon system ashore. Risk is the possibility of damage, inj ury or loss. The severity of a risk is determined by a combination of both the probability of an unfavorable event occurring and the severity of the event's occurrence. Risks are present in virtually all DoD developmental programs. Programs suffer from risks in technical challenges, unstable system requirements, missing schedule milestones, unpredictable funding and cost overruns. The DoD currently uses techniques to mitigate risks inherent in advanced system development. This thesis analyzes the AAAV's Program Definition and Risk Reduction (PDRR) acquisition phase risk management strategy. The thesis concludes by drawing from the lessons learned in the AAAV program during PDRR and analyzing the application of the lessons learned during the AAAV's cu rrent acquisition phase, System Development and Demonstration (SDD) / Captain, United States Marine Corps
27

PROJECT: SALTY BASTARD : WHAT IF AMPHIBIOUS MOBILITY WASN'T JUST A CURIOSITY, BUT THE NORM? / SNEKKJA

Walderhaug, Oliver January 2019 (has links)
Planet Earth is moving rapidly towards a point of no return in the climate crisis currently experienced, and while the debate is still raging on wether it is naturally occurring or not the temperature steadily increases - causing melting icecaps, expanding seas and rising oceans. It is the author's view however, that wether the change is man-made or not is irrelevant; as there is no other planet to conduct an experiment on. Therefor it needs to be treated as a problem generated by our species to best ward for the future generations. With rising seas come new problems, many problems that have accidentally been solved by developments in other fields. Take the development of artificial islands on the coast of Norway leading to the creation of entire floating civilisations in South East Asia. It easy to believe the coast lines among the nations of Earth will expand to take advantage of the additional space and comforts of newly created islands - and from this a new lifestyle will be born. A type of life where water plays a bigger role than ever before, and the need for mobility is greater than ever calls for urgent development in the nautical vehicle department. For what kind of vehicle would best be utilised for a life between the land and the sea in the future year of 2050? Throughout the often messy creative process many twists and turns have led the project forwards and backwards. Artistic exploration through sketching has been coupled with critical analysis of brand aesthetics and target markets. Conceptual evaluation and finalisation in 3D software and many, many loops back and forth generated visual material in both 2D and 3D to effectively communicate proposed solutions and artistic expression. The support from Scania and working out of the studio provided valuable insight for the brands future targets, but also the possibilities to collaborate and evaluate concepts along the process with engineers and modellers to ensure a believable final result. The feedback from the design team has strengthened the visual appeal of the vehicle, while the project in turn has helped the brand push its marque into the future in a visual sense. The final result is the Scania SNEKKJA, an amphibious vehicle capable of both land and aquatic travel in one single package adapted for most weather conditions. Pushing Scania further into the field of public transport, this vehicle retains the quality touch of the trucks currently delivered by the brand. It presents a new form language that stays true to the core values and roots of the manufacturer with a modern touch and offers a service provided by the brand as a personal mobility solution for people that want a more premium on demand service. A system that is always available and where convenience is the name of the game.
28

Nonlinear control of an unmanned amphibious vehicle

Unknown Date (has links)
The DUCKW-Ling is an 8.3 foot long, amphibious water plane area twin hull (SWATH) concept vehicle which is propelled by a pair of crawler tracks on land and dual propellers when water-borne. In its operational zone, the vehicle's dynamics change dramatically as it transitions from being completely water-borne and buoyancy supported to being completely land-borne and track supported. In the water environment, a cascaded, first-order sliding mode controller was used to control the surge and heading of the vehicle, and was capable of having a faster response when compared to using a proportional controller. Additionally, field trials of the DUKW-Ling show the capability of the vehicle to navigate and track predetermined waypoints in both terrestrial and aquatic terrains. In the transitional zone, the electric motor current from the tracks was used as the feedback mechanism to adequately actuate the propellers and tracks in the system as the dynamics of the vehicle change. / by Josâe L. Alvarez. / Thesis (M.S.C.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
29

The Ecology of the polytopic freshwater turtle species, Emydura macquarii macquarii

Judge, David, n/a January 2001 (has links)
An ecological study of Emydura macquarii macquarii in the south-east region of Australia was conducted between October 1995 and March 1998. E. m. macquarii is an abundant and widespread species of short-necked turtle that is highly variable in morphology and related life history attributes. No study in Australia had previously looked at geographic variation in biological traits in freshwater turtles, hence the level of variation in E. m. macquarii had been poorly documented. The principal aims of this study were to investigate the plasticity of life history traits across populations of E. m. macquarii and to speculate on possible causes. A more intensive study was also conducted on a rare and suspected declining population of E. m. macquarii in the Nepean River to determine whether relevant management and conservation measures; were required. The study involved comparing various life history attributes between five populations of E. m. macquarii (Brisbane River, Macleay River, Hunter River, Nepean River and Murray River). The populations were specifically chosen to account for the range of variation in body size within this subspecies. Body size (maximum size, size at maturity, growth rates), population structures (sex ratios, age and size structures), reproductive traits (clutch mass, clutch size, egg size, egg content, etc.) and other attributes were collected for each population. Patterns of life history traits, both within and among populations, were explored so that causes of variation could be sought. Geographic variation in Body Size and other Related Life History Traits Body size in E. m. macquarii differed markedly between populations. Females ranged in maximum sizes (carapace length) of 180 mm in the Macleay River to over 300 mm in the Murray River. E. m. macquarii was sexually dimorphic across all populations with females larger than males in all cases. Maximum body size was positively related to the size at which a turtle matures. The size at maturity in turn was positively related to juvenile growth rates. Age was a more important factor for males in terms of timing of maturity whereas in females it was body size. Morphological variation was not only great between populations, but also within populations. Maximum body size was unrelated to latitude; hence it was inferred that habitat productivity had the most important influence on geographic variation in body size. Population structures also differed between populations. Sex ratios did not differ in the Brisbane, Macleay and Murray Rivers. However, a male bias was present in the Nepean River population and a female bias in the Hunter River. Juveniles were scarce in the Brisbane and Macleay Rivers but numerous in the Nepean and Hunter Rivers. Geographic Variation in Reproduction There was large variation in reproductive traits across populations of E. m. macquarii. Nesting season began as early as mid-September in the Brisbane River and as late as December in the Hunter River, and continued until early January. Populations in the Hunter and Murray Rivers are likely to produce only one clutch per season while populations from the Macleay and Nepean Rivers can produce two, and on some occasions, three clutches annually. The majority of females would appear to reproduce every year. Clutch mass, clutch size, and egg size varied greatly both within and among populations. A large proportion of variation in reproductive traits was due to the effects of body size. E. m. macquarii from large-bodied populations such as in the Brisbane and Murray Rivers produced bigger eggs than small-bodied populations. Within a population, clutch mass, clutch size, and egg size were all correlated with body size, except the Nepean River. The variability of egg size was smaller in large-bodied populations where egg size was more constant. Not all variation in reproductive traits was due to body size. Some of this variation was due to annual differences within a population. Reproductive traits within a population are relatively plastic, most likely a result of changing environmental conditions. Another source is the trade-off between egg size and clutch size. A negative relationship was found between egg size and clutch size (except the Brisbane River). Reproductive variation was also influenced by latitudinal effects. Turtles at lower latitudes produces more clutches, relatively smaller clutch sizes, clutch mass and larger eggs than populations at higher latitudes. Annual reproductive output is greater in tropical populations because they can produce more clutches per year in an extended breeding season. Eggs that were incubated at warmer temperatures hatched faster and produced smaller hatchlings. Incubation temperatures above 30�C increased egg mortality and hatchling deformities, suggesting this is above the optimum developmental temperature for E. m. macquarii. Hatchling size was positively related to egg size, hence hatchling sizes was on average larger in the Murray and Brisbane rivers. However, population differences remained in hatchling size after adjustments were made for egg size. For example, hatchlings from the Hunter River were smaller than those from the Macleay River despite the egg size being the same. These differences were most likely due to the shorter incubation periods of hatchlings from the Hunter River. Nepean River The Nepean River population of E. m. macquarii is at the southern coastal limit of its range. This is a locally rare population, which is believed to be declining. This study aimed at determining the distribution, abundance, and population dynamics to assess whether any conservation management actions were required. E. m. macquarii in the Nepean River was mainly concentrated between Penrith and Nortons Basin, although even here it was found at a very low density (10.6 - 12.1 per hectare). The largest male caught was 227 mm while the largest female was 260.4 mm. Males generally mature between 140 - 150 mm in carapace length and at four or five years of age. Females mature at 185 -195 mm and at six to seven years of age. Compared with other populations of E. macquarii, Nepean River turtles grow rapidly, mature quickly, are dominated by juveniles, have a male bias and have a high reproductive output. Far from being a population on the decline, the life history traits suggest a population that is young and expanding. There are considered to be two possible scenarios as to why the Nepean River population is at such a low density when it appears to be thriving. The first scenario is that the distribution of the population on the edge of its range may mean that a small and fluctuating population size may be a natural feature due to sub-optimal environmental conditions. A second scenario is that the population in the Nepean River has only recently become established from dumped pet turtles.
30

Marina förmågor : kamp mot otydlighet / Marine Skills : The Fight Against Obscurity

Mikheel, Andreas January 2011 (has links)
Försvarsmaktens definitioner av olika förmågor är inte tillräckligt preciserade. Förmågorna beskrivs i dagsläget av Försvarsmakten på ett otydligt sätt där missförstånd kan uppstå. En analysmodell har tidigare utvecklats för att lösa detta problem. Analysmodellen är uppbyggd för att kringgå det problemet då faktorerna som vävs in har en direkt anknytning till verkligheten och de scenarion förbanden kan ställas inför. Faktorerna miljö, motståndaren och effekt utkristalliseras utefter förmågan och scenarion bildas. Eftersom modellen är relativt ny kommer det i denna uppsats behandla och kritisera denna. Modellen byggs upp och testas genom en analys av Amfibiebataljon 2014. Syftet med uppsatsen är att undersöka styrkor och svagheter med en analysmodell för att bättre bedöma marina förmågor. Resultatet är att analysmodellen ger en bra inblick i hur väl förmågor hanteras av förband. Nackdelen är främst det stora utfallet av scenarier vilken medför att modellen lätt blir svårhanterlig. Åtgärden mot detta är att generalisera de ingående faktorerna. / The Swedish Armed Forces definitions of various abilities are not sufficiently precise. In the current situation, the abilities are described in a vague way in which misunderstandings can occur. An analytical model was previously developed in a previous essay. The model is structured to circumvent the problem of the factors that are interwoven with a direct connection to the realities and scenarios troops may face. Environmental factors, the adversary and effects emerge along ability and the formation of scenarios. Because the model is relatively new, this paper will criticize it. The model is built and tested by an analysis of the Amphibious Battalion 2014. The purpose of this paper is to examine the strengths and weaknesses with an analytical model to better assess marine abilities. The result is that the analytical model gives a good insight into how well the abilities of units handled. The disadvantages are primarily the major outcomes of the scenarios which means that the model can easily become unmanageable. The measure against this is to generalize the input factors.

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