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296 Uppsatser om Wind speeds - Sida 16 av 20

Anslutning av vindkraft till ett svagt nät i Tidaholm

Vindkraftverk ansluts idag i snabb takt till elnät runt om i världen. Elnäten är ofta inte tillräckligt dimensionerade på platser där vindkraftutbyggnad är lämplig vilket leder till ett behov av nätförstärkning. Förstärkning sker konventionellt genom att övergå till en högre spänning, något som kan vara förenat med stora kostnader och ledtider. Bland annat därför har en filosofi med beteckningen smarta elnät uppstått, som handlar om hur elnätsystemet ska se ut när det är mer anpassat till de nya energikällornas karaktär och samtidigt medför ett mer effektivt totalutnyttjande. För vindkraftverk kan det då handla om att i högre grad än idag reglera produktionen och understödja nätet, t.ex.

Användning av geografiskt informationssystem (GIS) vid studier av nötkreatur i landskapet - en pilotstudie :

The Animal Protection Agency was in 2006, commissioned by the Government to: Evaluate how free range animals in the winter, can be kept and managed with special emphasis to animal welfare. The Animal Protection Agency was closed later in 2006 and the commission moved to the Swedish Board of Agriculture. The keeping of free range out wintered cattle, certain basic requirement are needed: by regulation, cattle should have access to a lying hall or other building that gives protection against aversive weather and wind and should offer a dry and clean lying area. There is a possibility for farmers that get an exemption from this regulation. But cases regarding farms which have had difficulties for this exemption has led to a discussion about if the animals can get the same protection in the nature which is comparable to a lying- hall.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Svartgran ? ett alternativ när allt ser mörkt ut? : en kartmodell för att visa lämpliga ståndorter för odling av svartgran

A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce.

Djupströbädd -bra för miljö och djur?

Deep litter is a system for animals kept in separate stalls, loafing and bedding in wind shelters. The litter can consist of different bedding, like straw and peat. The system is allowed to build over and to ensure optimal proportions it is necessary to add new straw regularly and to have good conditions. Important conditions are aerobic state, humidity, amount of organic substance and acceptable temperatures in the litter. The micro organisms are depending on temperature for their living conditions and to get the bottom layer in the litter to start burning.

Förändringar av marknadsdesign och deras påverkan på balanshållningen i det svenska kraftsystemet : En kartläggning och analys av de balansansvarigas arbetsgång

A future expansion of wind power in the Nordic power system makes the balancing for the transmission system operator Svenska Kraftnät (SvK) more complicated. Up to the hour of delivery the balance responsible parties? (BRP) makes prognoses and plans, for consumption and production, to help maintain the balance in the electrical grid. How well this is accomplished is affected by the setup of the market design. Therefore SvK has proposed the following possible changes in market design: Increase the imbalance costsIntensify the regulation of imbalancesIncrease the temporal resolution on the different marketsPresent the prices for balancing power in real-timeModify the balancing market to simplify auction of consumption bidsA mapping over the BRPs? processes within planning and trading on the day-ahead, intra-day, and the balancing market has been performed in this thesis.

Möjligheter och hinder för aggregerad förbrukningsflexibilitet som en produkt på reglerkraftmarknaden

Electricity production from renewable energy resources such as wind energy and photovoltaics is variable. Integration of these intermittent resources into the electricity system leads to new challenges in how to manage imbalance between supply and demand on the grid.One way to meet these challenges is to develop so-called smart grid solutions. One idea, called demand response, is to adjust the amount or timing of energy consumption, e.g. by control of household appliances, to provide flexibility that could be used to balance the grid. In aggregate, when applied to many units across the system, large volumes of energy could be made available when needed and this grid flexibility can be used as a product on the electricity regulation market.Despite the potential benefits, the number of demand response bids is currently low.

Noggrannhet vid låghöjdsfotografering från obemannad heliumzeppelinare

The development in photogrammetry has created possibilities for new methods in aerial images acquisition. Remotely-controlled imaging from an unmanned helium zeppelin is a new and relatively unexplored acquisition. The purpose with this degree project is to evaluate the accuracy of this kind of low-height photographing system, a task given from the consultant company WSP, in Sweden. Landbadet in Uddevalla municipality was chosen as a test field for the zeppelin. Seventeen images distributed over three strips were acquired from the flying height of 80 m.

Att arbeta med barn i blåsorkester : Fyra lärare om sitt ledarskap av ensemblespel

I denna uppsats undersöks hur några musiklärare går tillväga för att bygga en fungerande blåsorkesterverksamhet i de musik- och kulturskolor de är verksamma. Vad lärarna anser om planering, vilka mål de har med verksamheten samt hur de arbetar för att uppnå sina mål är frågor som besvaras i uppsatsen. Resultaten diskuteras med utgångspunkt i teorier om samspel och ledarskap. Datamaterialet består av intervjuer med fyra musiklärare på tre olika musik-/kulturskolor. Två av skolorna finns i Sverige och en i Norge.

Beräkningsverktyg för plattformar till seriekompenseringsanläggningar

ABB is one of the world?s leading engineering companies in power and automation technologiesand their solutions improve performance while lowering environmental impacts for energycompanies and industries. ABB FACTS designs equipment and plants for series and phasecompensation.This thesis has been performed at ABB FACTS on the Mechanical Design (DM) department inVästerås, Sweden. The purpose of the thesis was to develop and design calculations andsimulation tools for ABB FACTS?s standard series capacitor platforms.

Diktaturmänniskans fall : Bilden av Spanien i Per Wahlöös texter 1951-1962

Per Wahlöö is one of Sweden´s most famous crime writers. Together with Maj Sjöwall he revolutionized the swedish crime novel in the mid-sixties with the Martin Beck-series. Before that he was working as a reporter in the fifties and started writing novels about the oppression of man, power and totalitarian mentality in the end of the decade. Those novels (1959-1968) are called ?The dictatorship?-series.

Earth Wind and Fire tribute Projekt

Bildtraditioner, ämnesintegrering och elevperspektiv är viktiga ingredienser i denna C-uppsats. Undersökningen tar sin plats på en gymnasieskola som arbetar ämnesintegrerat, KF Gymnasiet, där jag själv är bild- och medielärare. Jag har valt att följa eleverna i en projektgrupp genom deras arbetsprocesser i ett ämnesintegrerat filmprojekt. Genom intervjuer och enkäter har eleverna fått berätta om sina uppfattningar om bildämnet; ett material som sedan bearbetas genom diskursanalytisk metod. Jag har arbetat med eleverna med både teckning och måleri, för att sedan ämnesintegrera bild med svenska och engelska i ett filmprojekt.

Klimatfaktorers inverkan på granbarkborrens svärmningsintensitet i Medelpad

The spruce bark beetle (Ips typographhus) is one of the 25 000 species of insects in Sweden, an insect of great economic importance because it can alone terminate forest of high value. During the past decade, insights of climate change received with increasing attention. If the future brings a milder climate in the north and therefore a longer growing season, one would think that it would only affect the forestry to the better? Yet in recent time, outbreaks after storm felling seems to occur more frequently. The Spruce bark beetle ruins millions of cubic meter of Norway spruce (Picea abies) in Sweden alone, with more frequent storm felling and a larger amount of wind thrown threes in the forests there will also be room for an advancing reproduction.

Igloo

This degree project has been performed along with Classic Garden in Gothenburg andBallongfirman Far & Flyg in Stockholm. Together we have developed a sun- wind- andrain protection. The protection is permanently assembled and mainly intended for publicenvironments as restaurants and outdoor cafés.The design on the sun protection was already done so our task has been to develop theconstruction and to build a prototype in scale 1:4 and one in scale 1:1. The look of thesun protection is approximately as the name implies, equal an igloo. The lamellae aregoing to fold out in different steps all the way down to the ground and the both sides willbe independently of each other.The first stage in the project was to develop differently principle proposal on how thefunction will work when folding in and out the protection.

Växter vid havet :

Detta examensarbete behandlar växter som trivs vid havet. Arbetet baseras på frågan vilka växter som tål ett vindpinat och utsatt läge? Arbetet beskriver vad man skall tänka på när man börjar planera en trädgård vid havet. I arbetet har jag tagit upp vilka träd och perenner som man kan använda sig av när man skall skapa en trädgård vid havet. Syftet med arbetet är att man skall kunna använda sig av mitt arbete när man åker till plantskolan för att inhandla växter.

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