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447 Uppsatser om Geography simulations - Sida 27 av 30

Konstruktion av värmespridare med grafit för flygelektronik

This master thesis was carried out for Saab Avitronics, a business unit of Saab ABactive in electronic systems for military aircrafts. Reliability and weight are of crucialimportance in this environment. To improve reliability and lower the weight graphitemay be used for electronics cooling. Graphite is an anisotropic material and hasthereof high thermal conductivity in two directions (in-plane) and a relatively lowconductivity in the third direction (through thickness).The purpose of this thesis was to investigate if graphite is an adequate thermalconductor to use in PCB carriers. The carriers support and cool the PCB by divertingthe heat dissipation from the PCB components to the edge.

Kombinerat system för ventilation och rumsuppvärmning : Parameterundersökning i simuleringsmodell för takvärmesystem

A large amount of our time is spent indoors in an artificial climate. To make the experience pleasant there are requirements on the ventilation and the heating system. At the present time the most common form of heating is a radiator system complemented with a ventilation system. A ceiling heating system with combined heating and ventilation can replace the two separated systems. The benefit with a ceiling heating solution is that it saves space since the radiator system is no longer needed.

Kartering av skogsskador hos bok och ek i södra Sverige med hjälp av satellitdata

Populärvetenskaplig sammanfattning: Kan satellitbilder användas för att studera skador på bok och ek?Sedan mitten av 1970-talet har man sett ökande skador på skogen i stora delar av Europa. Olika storlek på skadorna och att storleken på skadorna skiljer sig åt beroende på var man befinner sig har gjort det svårt att förklara orsaken. För att undersöka ifall skadorna även ökat i Sverige har Skogsstyrelsen utfört inventeringar på bok- och ekbestånd i södra Sverige under tre tillfällen; 1988, 1993 och 1999. Resultatet från undersökningen visar att konditionen hos bok och ek i södra Sverige har försämrats sedan den första inventeringen 1988.

Styrsystem : För en forskningsutrustning

The division of Engineering Materials at Linköping University, department of Management and Engineering, conducted a research project concerning Fatigue life of thermal barrier coatings during 2009. During this project equipment to provoke these fatigue failure by rapidly heating and cooling test subjects in cycles, was ordered.Design and manufacturing of the equipment was handled internally at LIU.The equipment was built using a furnace that is lowered and raised over the table where the test subject is placed. To keep the temperature of the furnace a lid slides in place to close the downward facing opening of the furnace when it is in the raised position. On this door there is nozzle that is used to cooling of the test subject by air.To make sure that the equipment can work independently you need an automation controller that can evaluate if movement can occur without danger of collisions. The control system also needs to monitor that all elements are performed according to plan.This degree project is based on a modular system from OPTO 22 and includes the configuration of a PLC that will be supplied with logic and a user interface.The degree project resulted in a graphic interface in which a user can set desired values for different parameters and get information about current values for them.

TRIM : ? Metod för att identifiera risker och uppskatta projekttider

ITT Flygt is a world leading company that mainly manufactures submersible pumps. A problem of ITT Flygt is that product development projects rarely manage to hold the estimated project time. It shows that something unexpected occurs in projects quite often, which results in delays. The delays can both be due to an optimistic time plan of projects and risks in product development projects which are not discovered at an early stage. This added with unforeseen delays makes it difficult for ITT Flygt to estimate the duration of their projects.The goal with the Master thesis is to examine a suitable method for simulation of project time.

Värmeöverföring i bergvärmesystem : En numerisk analys av den ringformade koaxiala borrhålsvärmeväxlaren

The borehole heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of ground source heat pump systems and thermal energy storages by increasing the energy efficiency of the borehole heat exchangers. For this reason, the annular coaxial borehole heat exchanger (CBHE) has been analyzed. This type of heat exchanger is interesting in terms of both thermal and hydrodynamic performance. A model has been set up in the program Comsol Multiphysics in order to investigate the heat transfer characteristics along the borehole.

Tetratermmodellering och regressionsanalyser mellan topografi, tetraterm och tillväxt hos sitkagran och lärk : en studie i norra Island

This study was made in an attempt to give the forest research centre Mógilsá a producedtetratherm map and a better understanding of how topography and temperature influencethe growth of two tree species. The digital tetratherm map model, covering the northernpart of Iceland, was developed to investigate the correlation between tetratherm and thegrowth of Picea sitchensis and Larix (sukaczewii + sibirica). The study confirms theusefulness of digital terrain models in providing data for a lot of different factors and forthe tetratherm model. Hopefully will this tetratherm map be used in future studies.Secondly, investigations were made correlating the growth of the two species againsttopographic factors representing height above sea level, distance to the sea, slope andtopex. Thirdly, investigations were made comparing the aspect and the ground shape tothe growth.The growth rate of Larix had strong significant correlations to the tetratherm and thedistance to the sea- factors.

Simuleringsmodell över Ålö AB

During year 2004 Ålö AB made significant change in their production process. The production of front loaders is nowadays highly automated with short operation times. To be able to control their process in a better way Ålö recently decided that they needed a tool for simulation of their production and to shift patterns. This final thesis started with a pilot study in Ålö?s factory in Brännland.

Igenväxning av Köphultasjö : bakomliggande orsaker och processer

Köphultasjön är en sjö som ligger inom Lagans dräneringsområde mellan SkånesFagerhult och Markaryd. Köphultasjö och dess närområde har under årens lopp utsatts avolika typer av påverkan, både naturlig och antropogen.Detta examensarbete undersöker och analyserar orsaker till Köphultasjöns igenväxning.Vidare beskrivs processer, som antas påverka igenväxningen av Köphultasjö, med hjälpav en igenväxningsmodell.De främsta indikatorerna på igenväxning av en sjö är gungfly och vass. Förekomsten avgungfly och vass pekar på både naturlig och antropogen igenväxning av Köphultasjö.Naturlig och antropogen igenväxningen av sjön har bekräftats med egna observationer ifält. Den naturliga igenväxningen motsvaras av den gungflyartade vegetationen, som harringa utbredning. Den nutida utbredningen av igenväxning består till en större del av vassän av gungfly.

Rödlistade kärlväxter i Göteborgs innerstad : temporal och rumslig analys av rödlistade kärlväxter i Göteborgs artdataarkiv, ADA

Biologisk mångfald i urban miljö har visats sig ha stor betydelse för människansrekreation och fysiska och psykiska hälsa. Samtidigt förbättras stadens hälsa genom debullerdämpande, luftrenande och klimatförbättrande egenskaper som vegetationen har.Syftet med denna undersökning är att utföra en temporal och rumslig analysmed avseende på antal och utbredning av rödlistade kärlväxter i Göteborgs innerstad under1900-talet. Utgångsmaterialet är Göteborgs artdataarkiv, ADA, en databas framtagen avGöteborgs miljöförvaltning som innehåller observationer av rödlistade och andra skyddsvärdaväxt- och djurarter. Då databasen är en sammanställning av olika inventeringar över lång tidär skillnaderna från ett material baserat på en systematisk inventering stora. Vagalokalangivelser och okänd observationsfrekvensen i ett område är faktorer som påverkarsäkerheten i materialet men det kompenseras genom ett stort antal observationer undermycket lång tid.Den temporala analysen av antalet rödlistade kärlväxter i Göteborgs innerstadvisar på en tydlig nedgång i rapporterade arter.

Konstruktionstudie av en ångexpander

This thesis applies to a novel steam expander, one part of a steam engine system, a wobble plateengine. The piston in the expander moves axially with the outgoing rotating shaft and is locatedon a plate, why the engine type is called axial engine. When steam is applied to the plungers theplate wobbles creating a rotation on the shaft going thru the wobble plate. The steam expander issupposed to be used in exhaust gas recovery (bottoming cycle) applications and small scaleenergy production. The commissioner is Ranotor Utveckling AB.

Simulering av simulinkmodeller med Extended Kalman Filter

Simulations of simulink models using Kalman filters are often very time-consuming. This problem depends mainly on the fact that the Kalman correction has to be performed at each sample instance through the whole simulation. The goal for this thesis work is to reduce that time-consumption for the filtering part (the integration partis treated in a complementary report) of a simulation. Furthermore a Matlab routine to perform parameter tuning and finally a graphical user interface is developed.The filtering part of the simulation in this thesis is based on an Extended Kalman Filter (EKF). The time optimization of this filter considers searching for the possibility to replace the today?s existing Matlab functions that is used to perform the filtering calculations.

Mekanisk integration av en IR-detektor i en Stirlingkylare

The master thesis ?Mechanical Integration of an IR-detector in a Micro Cooler? has beenperformed at FLIR Systems AB in Danderyd. FLIR Systems is a world leader in the design,manufacture and marketing of thermal imaging camera systems.The thesis project is divided into to two areas, Production Method and Noise.The Production Method concerns the positioning of a detector on the cold finger within the IRcamera.The detector has to be positiond with very high accuracy at the center of the cold finger,so it can be placed in line with the optical axis to avoid movement of the picture during zooming.The positioning of the detector is at present done with the help of specially designed guides on aplate on top of the cold finger. The design workes well but the special machining needed for thisplate is very expensive.The goal concerning the production method was to derive a new more cost effective method forthe assembling and positioning of the detector on the cold finger by replacing the guides on theplate with a reusable equipment or some other alignement operation.Several concept ideas have been generated with the help of concept generation methods in theform of concept classification trees and concept combinational tables. Two of these conceptswere selected to be further refined.

Lane Keeping Aid : ett förarstödjande system för bilar

Many traffic incidents are due to the driver?s lack of attention, resulting in dangerous lane departures, either sliding off theroad or into the oppose lane. These kinds of incidents often have serious outcomes, which has led to much effort being concentrated on preventing or lessening the damages when the incident is already a fact, for example by installing safety belts and air bags. These measures may be considered to be acts of so-called passive safety. Active safety on the other hand, means that the safety systems intervene before the incidents have occurred.

Utvärdering av en väggkonstruktion utan PE-folie : Med en undersökning av hårdvaxolja som diffusions-/konvektionsspärr

District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.

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