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25 Uppsatser om Turbulence - Sida 1 av 2

Projektering av vindkraft i turbulensintensiva områden : med fallstudie för Wallenstams planerade park vid Skuggetorp

Along with the rapid expansion of wind power in Sweden during the last decades the competition about favorable areas has hardened. This among other reasons has caused the projectors to look into development of wind power in forests. There are several aspects regarding fatigue loads on the constructions that are severe in complex terrain, among which Turbulence is one. The levels of Turbulence which are accepted in order for the turbines to face a life length exceeding 20 years are regulated by the International Electrotechnical Commission, (IEC). In order to keep the Turbulence below these levels there are three major steering tools to use: The ambient Turbulence decreases with height and can therefore be regulated by the hub height of the turbines.

Utvärdering av svensk vindkraft : Skillnaden mellan skogs- och traditionella placeringar

During the last years commercial Wind Power Turbines (WPT) has become larger regardingto the generator sizes and hub heights. Available hub heights around 100 meters is nowcommon, which has led to profitability for WPT located in forests where there normally are tolow wind speeds. The current knowledgement regarding Turbulence and the variation in thewind profile for the outcome of the power production for the WPT in forests is limited.In this Master of Science thesis an investigation concerning forest located wind power plantshas been made. The purpose has been to investigate if plants located in forest perform lesscompared to wind power turbines located at more common locations.The analyses are based on statically material for determining the availability,production/generator size, production/hub height, production/swept area and how thetopography affect the production results.The analyses show that the variation in production result for WPT located in forest comparedto turbines located at other locations is small. The availability is high and the productionresults are good..

Design and Analysis of an All-optical Free-space Communication Link

Free Space Optics (FSO) has received a great deal of attention lately both in the military and civilian information society due to its potentially high capacity, rapid deployment, portability and high security from deception and jamming. The main issue is that severe weather can have a detrimental impact on the performance, which may result in an inadequate availability. This report contains a feasibility study for an all-optical free-space link intended for short-range communication (200-500 m). Laboratory tests have been performed to evaluate the link design. Field tests were made to investigate availability and error performance under the influence of different weather conditions.

Simulering av kabelbränder i sekundära säkerhetssystem med CFD-koden SMAFS

This report contains CFD-simulations of cable tray fires in nuclear power plant applications with the CFD-code SMAFS. Furthermore the report evaluates the use of CFD-codes within this kind of problems. The assessment of this report is that there is a tendency towards the good use of CFD-codes but before using it solely more research has to be done on the subject..

De nya riksdagspartierna och den politiska dagordningen

Engblom, Gustav (2009) De nya riksdagspartierna och den politiska dagordningen ?The new parilament parties and the political agenda.?1988 and 1991 the swedish parties Miljöpartiet, Ny demokrati and Kristdemokratiska samlingspartiet made it over the 4 percent threshold and successfully entered the Swedish parliament. Sweden was once described as one of the most stable political systems in the world, but the parliament elections of 1988 and 1991 showed that Sweden was no exception from the growing instability in west democratic political systems.The stability and instability that followed in the west democratic political systems is believed to be explained by the political parties? efforts to adjust to changes in their political environment. This has lead them to cartelize and the cartel party is believed to prefer stability over triumph for various reasons.The established political parties are believed to be able to manipulate the political agenda in such a way that political topics that would have caused great Turbulence in the political system, if debated, are kept away from the political agenda.

Klarluftsturbulens (CAT) : går det att undvika?

Turbulens är ett väderfenomen som har orsakat många olyckor och incidenter. Speciellt farligt är klarluftsturbulens eftersom fenomenet ej är synligt för blotta ögat, samt att det kan uppstå mycket plötsligt. Mycket pengar och resurser har lagts ned för att ta fram system som skall kunna detektera och automatiskt rapportera turbulens. Denna uppsats beskriver kortfattat hur några av dessa system fungerar samt hur systemen skall bidra till att piloter lättare skall kunna förbereda för eller undvika turbulens. Uppsatsen beskriver system för prognostisering, detektering och automatisk rapportering av turbulens med tyngdpunkt på klarluftsturbulens..

Kampen mellan etablissemang och näthatare - En studie om näthatsdebatten

This essay examines the Swedish debate on Internet hate with focus on theories concerning Internet as a public sphere, sociocultural Turbulence and subaltern counterpublics. Examining material fromnewspapers, alternative news media and discussion forums, with an hermeneutical influenced method, the task is to understand the Internet hate debate, and the study wishes to discover its relations to biggercontexts, such as social transformations and power dynamics. The conflict evolves between the establishment (journalists, writers, politicians et cetera) on one part, and Internet ?haters? on the other.The examined theme also shows a conflict where the two combatants show not only two opposite views on what Internet hate is, but also shows two different conceptions of the world..

FUNDAMENTALA SAMBAND I TURBULENTA PERIODER: - Om tillväxtens och avkastningens påverkan på börsvärdet under perioden 1997-2005

This thesis investigates the effect of profit growth and profitability on market capitalization amongst Nordic companies during the turbulent period 1997-2005. Our results suggest that profitability have a significant impact on market capitalization for six of the nine years studied, whereas profit growth does not seem to affect market capitalization. Consequently, our results imply that the effect of other factors on share price performance may be greater than previously suggested. These findings are only partly in line with theories on corporate valuation which suggest that market capitalizations are to a great extent driven by both profit growth and capital returns, regardless of whether the stock market is particularly unstable..

Går det att mäta blodtryck med fotopletysmografi och bioakustisk sensor i kombination?

The aim of the work was to investigate the possibility to combine information from PPG and bio-acoustic technology to extract information that is related to the blood pressure. The measurements have been carried out with several different configurations. First the relation between arterial sounds and the PPG-signal was studied. After those measurements with both PPG and the bio- acoustic technique was concluded on people in different positions and after riding a bike. The goal was to vary the blood pressure.

Projektering av vindkraftspark i Juddhult, Småland

The aim with this study was to collect fundamental information, and to plan, a windpower farm in Juddhult , Småland in southern Sweden. The goal is to collect the bestavailable projecting planning support. The pieces of this projecting planning supportthat will be presented is; Environmental Consequence Description (MKB), productioncalculations, comparisons between different plant types, economic calculations, evaluatethe economy and give some farm design suggestions. The imagined wind farm will belocated in forest environment and which may cause a number of new problems. Specialinterest that will be affected, where special consideration because of the forestenvironmental is requested is, hunting, wetlands, ancient monuments and windTurbulence.

Krafter på rörsystem vid transient flöde : En jämförelse mellan RELAP5 och Fluent

At Forsmarks Kraftgrupp AB (FKA) forces on pipe systems due to transient flow are frequently calculated as a step to verify their structural integrity. In nuclear industries these forces are often calculated with a one dimensional thermal-hydraulic analysis-code called RELAP5. When calculations regarding more complex geometries are needed, the three dimensional code Fluent is often used. This code is highly time consuming and requires large computational power.This projects aim is to compare calculations of pressure, flow and forces carried out by RELAP5 and Fluent for an arbitrary pipe section during transient flow conditions. This has been accomplished by constructing a simple geometry for which a transient flow is simulated in both programs.

Vinkärlsetiketterna berättar : En textstudie

This paper examines the texts written on shards from wine-jars found at El-Amarna, Tutankhamuns tomb (KV 62) and Deir el-Medina. Information concerning the administration of wine and its production, found in these texts, is examined. Wine was an important element in Egyptian society and a common iconographic motif in tombs at Thebes during New Kingdom.A survey on previous research on the subject is presented. This is followed by analysis of the different reoccurring elements found in the texts. A definition of the standard formulation of the wine jar label texts is given and the minimal level of information needed for the administration of wine production and distribution is identified. The chapter of the analysis deals with the various types of information given in the label texts, such as date, wine classification, and function.

Upplevelser av hälsa och lärande relaterat till organisatoriskt förändringsarbete : En intervjustudie med sjuk- och undersköterskor.

Work and health are strongly connected because people spend the most part of their adult life in a workplace. The work environment influences the fellow co-workers experience of health and learning in different ways. Accordingly the organizations influence has by doing so, created a great significance to fellow co-workers experiences. Organizational changes often create Turbulence within an organization and are often experienced negatively by the fellow-co-workers even if it will give positive effects later. The aim of this study was to illuminate nurses- and assistant nurses experiences of health and learning related to organizational changes.

Vem använder budget? : En kvantitativ undersökning av budgettillämpningen i olika organisationer

Weber and Linder (2005) have enlightened that the focus of the current debate on the budget?s to be or not be, has been on trying to find a general tool, which fits best in all situations. They argue that the budget may be more appropriate for organizations in certain circumstances, than for others. They claim that there is a gap in research concerning the situations in which the budget may be appropriate, or when Beyond budgeting is preferred. It is this gap we are trying to fill with our thesis.The purpose of the thesis is to explain which situational factors that affect the organization's use of budgets for the functions the budget can fulfill.

Värdepapperisering av samhällsfastigheters hyresflöden : En attraktiv finansierings- och investeringsmöjlighet för att bygga vård- och äldreboenden till en åldrande befolkning?

The number of elderly people has been steadily rising in Sweden for a long time and as a proportion of the population, the increase has been even greater. The population structure in the country means that in the not too distant future, there will be a sharp rise in demand for care and elderly accommodation.A tighter credit market as a consequence of new rules and regulations with a stricter capital and liquidity requirements combined with market Turbulence, has made financing property developement more difficult and more expensive which has resulted in many companies using alternative sources of finance.DEmand for safe investments with low risk is high as the market is volatile and banks, pension funds, fund management and life insurance companies are looking for investments outside the stock market that can deliver a safe return in the longer term. There has also been a debate about whether institutional investors as the AP pension funds really should own properties directly.As properties for care and elderly accommodation are definable assets with predictable payment flows, long leases and often a local authority as tenant that would not risk cancelling payments, these would be highly appropriate for securitisation, i.e. to issue bonds or other tradable securities based on the cash flows from the assets.In other words, the securitisation of rent flows would offer the opportunity to create an attractive investment product of the type being demanded, well suited to institutional investor requirements, while at the same time, it can provide an attractive financing opportunity to meet the need for more care and elderly accommodation..

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