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345 Uppsatser om Linear quadratic - Sida 18 av 23
Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population
The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural
forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation
has been done by the Swedish Environmental Protection Agency. In this work I have
therefore investigated how a translocation of the species succeeded after 17 years. I aimed
to study the species dispersal biology, its substrate preferences and the supply of suitable
wood on this site. The study was performed during 2012 in Pansaruddens nature reserve
close to Uppsala in Sweden, which is a spruce dominated forest.
USA versus al-Qaida : linjärt tänkande mot asymmetriska metoder - en studie kring den amerikanska problematiken i kampen mot terrorismen
Syftet med denna uppsats har varit att undersöka på vilket sätt attacker utförda av al-Qaida kanhänföras till begreppet asymmetri och på vilket sätt man kan tolka den amerikanska administrationensrespons på dessa som uttryck för ett linjärt tänkande. Vidare vill jag undersöka vilka svårigheter somkan uppstå i relationen mellan en linjär omvärldsuppfattning och asymmetriska metoder. För attuppfylla syftet med uppsatsen kommer tre av al-Qaidas attacker att studeras. Dessa är: attacken mot deamerikanska ambassaderna i Afrika, 1998, attacken mot USS Cole, 2000 och attacken 11 september,2001. Rapporterna från den amerikanska administrationen efter respektive attack kommer att utgöragrunden i mitt empiriska material.
Cassava as an additive in biomass fuel pellet production :
In this study, the effects of using fine milled cassava stems as an additive in biofuel pellet production was compared to the effects of refined starch addition. The bulk biomass fuel raw material, to which the additive was added, was a blend of spruce and pine sawdust. An experimental design in the factors cassava/starch content, moisture content and material temperature was used. Measured responses were pellet bulk density, pellet durability, amount of fines, pelletizer motor current, pellet temperature, die temperature and CV for pelletizer motor current (a measure of process stability). Each response was modeled by multiple linear regression (MLR).
Att rädda det förgångna : Om Walter Benjamins historiska materialism
The present essay concerns Walter Benjamin?s thought regarding history and temporality as he articulated it in his last work that was only published posthumously: ?U?ber den Begriff der Geschichte?. The purpose is to analyze Benjamin?s construction of historical materialism and to suggest a reading of it as directed towards an opening of history. For Walter Benjamin, every moment presents itself as a possibility of radical otherness: a possibility for things to be different.
Utveckling och konstruktion av dämpare och låssystem för vågkraftverk
The division of Electricity at Uppsala University is developing a wave energy converter(WEC) consisting of a linear generator connected to a bouy at the water surfacethrough a wire cable called the connection line.During extreme conditions, the wave power plant will experience forces up to 500kN, which lead to unnecessary wear and will ultimately cause the failure of theconverter. To prevent this there is a need for a damper.The wave energy converter works at a maximum efficiency when the translator?sare centered with respect to the stator. Due to tidal movements the position of thetranslator can deviate. There for a mechanical divice that will compensate for this isneeded.This report describes the further development of an earlier project where a tidalwave compensator for a wave energy converter of Seabased AB was developed.
Robotiserad produktionsanpassad magnetmontering för vågkraftverk
This thesis work includes studies and simulation how magnetization of the translator in a linear generator for wave power can be automated. The translator is the moving component in the generator that is "dressed" with permanent magnets. The translator is magnetized with rectangle-shaped permanent magnets that are today's strongest permanent magnet type of neodymium-iron-boron (NdFeB).Eight equivalent metal sheets are mounted around the translator. The plates have milled tracks where 106 permanent magnets per sheet are mounted. Today the assembling of the magnets is done by hand, which is a very tedious and time-consuming work. This project presents investigations about the automation of the translator magnetization theoretically and simulation results are preformed in ABB's robot simulation software RobotStudio. Even robot-held tool was designed that enables the robot to be able to magnetize the translator in a simple manner. The investment cost is roughly 1.5 million SEK. With an economic life-time of five years, the investment costs are estimated to 24000 SEK / month. According to the calculations, this project is very motivated to implement, as it provides savings up to 17 000 SEK per translator which is 10.2 million SEK assuming that the robot cell is operating at full speed the whole year.According to this thesis work the result is a 4x9 meter cell with two industrial robots of the type ABB IRB6650S.The cycle time to magnetize one translator was calculated to about 10 hours.This prototype of project can possibly be implemented in a full-scale production line and performed according to the calculations and simulations presented in the report. Further work is suggested to improve the tool.Lyssna .
Integrerad arbetsprocess mellan projektör och konstruktör, För effektiv och kvalitetssäker projektering med Tekla Structures och SAP2000
The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.
VEM ST?DJER BIST?NDET? En kvantitativ studie om vilka faktorer som p?verkar attityden gentemot EU:s internationella bist?nd
The discussion regarding international aid tends to be highly debated for long periods of time.
Some individuals are very positive towards aid and some individuals are less positive towards
aid. This study aims to broaden the understanding of the aspects behind that. The previous
research tends to focus on aid allocation within the EU, or which macro factors could influence
which donor countries give to which recipient countries. This study aims to add to the research
with which aspects at the individual level can influence the individual's attitude towards
international aid from the EU.
Identifiering av röjningsbestånd med hjälp av flygburen laserskanning
Bergvik Skog is one of the leading forest companies in Sweden who use airborne laser scanning for forestry information. They utilize laser data retrieved by the Swedish National Land Survey to describe the forest holdings and facilitate planning for thinning and final felling operations. However, the possibility to identify stands with clearing needs by using laser scanning data has not been tested in a large scale. The data used in the current study are field data from The Swedish National Forest Inventory in combination with laser data from the Swedish National Land Survey acquired in 2009. The collected data is used to find one or several laser variables that best describe the relationship of the field measured samples with clearing needs.
Modeller för utvärdering av set-up för återvinning av lastlister inom IKEA
Reverse logistics is getting more and more attention both from companies and the public. It is an area with the possibility for companies to do good in the eyes of the public. This work focus on the return system of a one-way handling material called the loading ledge. The loading ledge is developed by IKEA as a substitute for the EUR-pallet in transports from suppliers with a long distance and even flow and in transports from suppliers with short distance and uneven flow. The loading ledge is made out of 100 % recyclable plastic.The purpose of this work is to find the most efficient set-up for recycling of loading ledges within IKEA on a European level from a transport and handling point of view considering aspects like cost, environment, time and, from an administrative point of view, user-friendliness.Who will the participants of the set-up be, where will they be located, which transports are needed and which income and costs does the set-up generate, are questions that will be answered.
Utveckling av nytt koncept för positioneringsslid
A manufacturing machine at the engineering company Sandvik Coromant has a positioning table which task is to move an item linearly. The positioning table has a linear motor capable of high velocity and acceleration. This makes it possible to achieve short cycle times and a more profitable production.The purpose of this thesis is to bring forward a new concept which is more adapted to the requirements of the positioning table. The reason is that the current positioning table provides an unnecessarily positioning accuracy of 0.01 mm, while the requirement for the positioning accuracy is just 0.1 mm. The goal is to reduce manufacturing and component costs.To develop a suitable solution an approach for the concept development process has been performed.
Variationer av klor, svavel och aska i havrekärna : odlingsfaktorernas inverkan på havrens bränsleegenskaper
The increasing oil prices during the last years have made it profitable to use cereal grains as a fuel. When compared with wood, cereals contain higher amounts of Cl, S and ash. The Cl and S content makes the gases from cereal combustion more corrosive than gases from wood combustion. The goal of this master thesis was to find out the variation of Cl, S and ash content for oat grain grown under different conditions. Oats was chosen because in Sweden it's considered as the cereal with the best fuel qualities.
Optimering av ett småskaligtvattenkraftsystem
This master thesis covers the seasonal planning of a small scale hydropower system. The system in this study is owned and operated by Mälarenergi Vattenkraft AB. The total system consists of 4 different main rivers with 24 hydropower stations and several dams. The total installed power in the system is 43.75 MW. Most of the hydropower stations are regarded as small scale hydropower stations and thus entitled to green certificates.In this report the issue of planning is formulated as an optimization problem.
Kostnadsutjämningen inom Barnomsorgen i Sverige - en diskriminantanalys
Sweden?s District councils and Country councils are in itself to a large extent responsible for the state financed welfare. Because of this, Sweden has a contribution- and adjustment system. The reason for this system is to create equal chance, for all District councils and Country councils, to be able to give the citizens service independently of their income and non-influential structural differences. The adjustment is built upon the so-called standard cost method, which contains four different parts.
Modellering och optimering av Lycksele kraftvärmeverk
Stigande kostnader för bränsle samt pressade elpriser gör att produktionen för ett kraftvärmeverk bundet till ett fjärrvärmenät måste optimeras. I denna rapport presenteras en ?Mixed integer linear programming? modell över Skogsbacka kraftvärmeverk, dess ackumulatortank, extrapannor och Lyckseles fjärrvärmenät tänkt att kortsiktigt optimera energiproduktionen. Kraftvärmeverket har en panneffekt på 50 MW och turbineffekt på 16 MW. Modellen tar hänsyn till fjärrvärmenätets framledningstemperatur och returtemperatur samt hur dessa parametrar påverkar kraftvärmeverkets drift samt hur de påverkar ackumulatortankens lager och laddning.