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296 Uppsatser om Wind speeds - Sida 10 av 20
Fortsatt gran eller självföryngrad björk efter stormfällning? : en ekonomisk analys
The southern part of Sweden, Skåne, is frequently exposed to storms causing great damage to Norway spruce (Picea abies L. Karst.) stands. A storm during the winter 1999/2000 raised the attention of the problem. A lot of forest owners got large areas of spruce stands wind thrown during this storm. Can naturally regenerated birch (Betula sp.) be an alternative on these wind-exposed sites? This was the main question I was facing when discussilig the problems with Esben Möller Madsen, Söderåsens forest district.
The aim of this master thesis was to present an economic analysis of Norway spruce versus
birch.
Nollenergihus i Borlänge : Är det möjligt med biomassa, solenergi och vindkraft?
This report is of technical character and treats how to plan a small building in Borlänge, Sweden.The technical components that have been treated in the report are the construction, foundation,installations and thermic abilities of the house. In addition to planning this house the report alsocontains a part that deepens in net zero energy buildings. The purpose of the report is toinvestigate if the house in Borlänge can be constructed to meet net zero energy buildingdemands.Energy efficient houses such as passive- and net zero energy houses are showing more frequenton the market in Sweden. Ongoing climate changes and growing consciousness about theenvironment in society have contributed to that the environment is a well discussed topic. Toconsume small amounts of energy and at the same time produce local energy is thereforesomething that lies in the future and future houses.
Cupsystemet : En kvalitativ fallstudie av en mobil webbtjänst
The thesis describes the following main question: Will the administrative labour during football tournaments be made easier with the help from a mobile web service or will it convey to unnecessary extra work? To be able to give a good and qualified answer to this question, the thesis will in the beginning describe how the technique for such a system might look like and also describe the existing administrative moments during a football tournament, this is too give the reader a deeper understanding for further reading. The thesis then goes on to describe a concrete system which is tested on three football tournaments. On the basis of the tests, interviews and through analysis of these the thesis will be able to answer our questions. The result which we present in the thesis have unfolded through testing of the system on three chosen football tournaments.
Skogsskötsel för att minimera stormfällning över järnväg :
The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.
Konstruktion av statorstomme för synkrongenerator : Förslag på design av statorstomme för användning i vertikalaxlade vindkraftverk
This thesis describes a conceptual design of a support frame for a synchronousgenerator used in a vertical axis wind power plant. In this system the generator isplaced on ground level. The thesis also considers the design of housing for thesupport frame and generator. The concept presented in this report is based on anearlier design. Besides geometric design, simplified simulations has been run in orderto optimize some of the parts included in the construction considering naturalfrequencies and structural strength.The result is presented as CAD-models andan assembly drawing..
En analys av nattliga koldioxidflöden i en boreal barrskog avseende spatial och temporal variation
Carbon dioxide in the atmosphere contributes to the greenhouse effect, which is essential tolife on our planet. Furthermore, it plays an important part of the photosynthesis andrespiration of the world?s organisms. Since the start of the industrial revolution the amount ofcarbon dioxide in the atmosphere has increased exponentially. The main source is theextensive burning of fossil fuels.
Vindkraft under utveckling
Vindkraft är ett miljövänligt energislag med stor utvecklingspotential, både i Sverige ochutomlands. I det här examensarbetet sammanfattas de viktigaste bitarna av kunskapen sombehövs för att förstå sig på vindkraft, med fokus på meteorologi och kommunikation medkonsultföretag i branschen. På grundval av litteratur i ämnet, konsultrapporter beställda av ettsvenskt företag i branschen och diskussion med experter ges här en grundläggande översikt imeteorologi för vindkraft, vilken innefattar kunskaper om klimatet i allmänhet ochvindklimatet i synnerhet, förståelse för luftens flöde, den geostrofiska vinden och hurtopografi och dylikt påverkar luftens strömning i gränsskiktet. Vidare diskuteras hur energin ivinden tas till vara, med en sammanfattning av viktiga tekniska detaljer; vindkraftsspecifikastorheter och uttryck, energiförluster och effekterna av att placera många vindkraftverk i engrupp; vakeffekten. En av de dominerande delarna av alla konsultrapporter som studerats ärhur man analyserar och behandlar vinddata för maximering av tillförlitlighet och relevans.
Target Capital Structure and Adjustment Speed- a dynamic panel data analysis of Swedish firms
The purpose of this thesis is to test whether firms have target capital structure, and if so with what speed they adjust toward this target. Findings that support this purpose are also in line with the trade off theory. One of the key elements of this thesis is the method used, which successfully enables fulfilling the purpose. The panel data method captures the data characteristics of the cross sectional and time series dimension. By using this approach the dynamic effects of capital structure can be studied, thus if there actually is an adjustment towards a target the speed can be estimated.
Cupsystemet - En kvalitativ fallstudie av en mobil webbtjänst
The thesis describes the following main question:
Will the administrative labour during football tournaments be made easier with
the help from a mobile web service or will it convey to unnecessary extra work?
To be able to give a good and qualified answer to this question, the thesis
will in
the beginning describe how the technique for such a system might look like and
also describe the existing administrative moments during a football tournament,
this is too give the reader a deeper understanding for further reading. The
thesis
then goes on to describe a concrete system which is tested on three football
tournaments. On the basis of the tests, interviews and through analysis of these
the thesis will be able to answer our questions.
The result which we present in the thesis have unfolded through testing of the
system on three chosen football tournaments. The differences in way of labour
pre and post the system have been analyzed and through interviews the value
of these changes have been assessed.
The results achieved in the thesis are as follows, the presented mobile web
service does not only decrease the total work effort made by the tournament
officials it also speeds up their work.
Scenarioanalys över Sveriges elproduktion år 2050 : Kan Sverige försörja sig med 100 % förnybar
The aim of this report was to investigate if Sweden can have 100 % renewable electricity production in the year 2050. The conclusion is that it is possible but under certain conditions. For instance wave power must be in commercial use. When wind power and solar power represent a large percentage of the electric production there will be a lack of electric power during the winter but during the summer there will be a surplus of electric power. Both the surplus and the lack of electric power need to be taken into account.
WSC Wind Science Centre : Centret för vindenergi
Målet med projektet har varit att designa en byggnad där information om vindkraft kan presenteras. Utgångspunkten iprojektet har varit upplevelsen med ett antal studier som grund. Området som berörs är Borgsjö som är optimalt läge fördenna typ av informationsbyggnad. Genom studiebesök, enkätundersökning, intervjuer och analys har ett antal konceptframställts. För att engagera besökarna så har även en enhet för utomhusbruk tagits fram där användaren med sin egenstyrka kan generera elektricitet och jämföra med miniverket.
Ett kommunikationssystem för fiberoptisk överföring av bilddata förvärvad av en miniatyriserad undervattensfarkost
This report describes the development and implementation of a system for transmitting digital information at high speeds from a miniaturized submersible developed by the Ångström Space Technology Centre at Uppsala University. For instance, the vehicle shall transmit image data ? even stream live video - through an optical fibre to a monitor in a ground station. Hence, the system shall be used both to convert the image data to make it transmittable, and to recreate it at the receiver.The work includes a pre-study of the programming language and the technology used. A concept for the solution is presented together with main components later broken down into internal functions.
Val av liggplats och väderskydd hos dikor vid utedrift vintertid
If you keep cattle in a herd outside all year round on big varying grounds, their possibilityto perform their natural behaviour increases. This way of keeping cattle requires that youprovide them with their other needs, like shelter and a dry and clean resting place.According to the animal welfare authority´s regulations on livestock farming, only animalsthat are suited to stay outside during the cold season are allowed to be kept outside. Theyshould also have access to a shelter or another building that gives them protection from theweather and wind and provides a dry and clean resting place.Research has shown that as long as cattle do not get exposed to precipitation and wind theywill manage low temperature well. Some of the things that will affect how well the animalshandle different climates are the isolation ability of the fur, the animals´ body size and thefeed intake. A dry lying place that is both insulating and moisture absorbent is also of greatimportance.
Energieffektiv Linjesjöfart Till Och Från Gotland
The ferry traffic to Gotland is essential for the island?s ability to live and develop. Yearly, it transports 1,6 million passengers, 500 000 personal vehicles and 750 000 lane meters of freight with four Ro-Pax ferries. The traffic is controlled and subsidized by the Swedish government since 1971 in order to guarantee the inhabitants and industry of Gotland a satisfactory transportation service. As a consequence of the past decades increased traffic quality, mainly due to a decrease in crossing times, the traffic?s environmental impact and costs has also increased.The Master Thesis proposes a new energy efficient traffic arrangement that satisfies the users? preferences in the same extent as today.
Masskattning av tunga fordon i realtid genom systemidentifiering
As trucks are getting more and more advanced, information about their weight has become a key factor for controlling them in a more fuel efficient and safe manner. Knowing the mass of a heavy duty vehicle in real time has been a difficult challenge for the truck manufacturers. With the processing power for electronic control units in trucks steadily increasing, more advanced algorithms for calculating the mass has been developed, but at the moment there still is a wish for better performance.Since there is a lack of good information regarding the external forces acting on the vehicle, forces that depends on the slope of the road, foundation of the road and the wind, the methods have to be able to disregard these. Such an approach, based on an indirect least square solution, has been evaluated in this thesis. The results have been promising and based on these a recommendation about further evaluation has been made..