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2197 Uppsatser om Energy exchange - Sida 65 av 147

Utbyte av massaved och biobränsle i några typbestånd av Contorta :

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.

Marknadsundersökning inom datacenterbranschen : Undersökning av tekniska inköp, med fokuspå kyllösningar

The purpose of this thesis is to examine how investments are justified in the Swedish data center industry, with a focus on cooling equipment. This is achieved through semi-structured interviews with 20 different interviewees. These interviewees represent different facets of the industry and facilitate an understanding of which factors, such as: investment costs, operating costs, reliability, environmental impact and the influence of external and internal actors, come into play and to which degree they impact the investment decision-making process. The results show that primarily low operating cost in the form of low energy consumption is the driving factor when it comes to the procurement of new equipment. A lower environmental impact is a positive side-effect of lower energy consumption.

Vindkraftsetablering i skog

This thesis assignment at C-level is focused on calculation models and prediction methodswhish can be used in the stage we call ?prospecting? of possible windmill locations. Thelocation is southeast of Halmstad at the Farm ?Stjernarpsgods?. The rapport has two mainareas directed towards this task.

Kommunikationssvårigheter inom autismspektrumtillstånd : En fallstudie om användningen av det alternativa kommunikationsverktyget PECS

Syftet med denna studie är att undersöka användningen av det alternativa kommunikationsverktyget PECS (Picture Exchange Communication System), som är vanligt förekommande hos personer inom autismspektrumtillstånd (ASD). Hos människor inom ASD är det vanligt med kommunikationssvårigheter samt utpräglade beteendeproblem. Genom intervjuer med skola, habilitering och boende har PECS studerats utifrån olika aspekter. Hur går inlärningen till? Hur används verktyget i det dagliga livet? Vilka för- och nackdelar upplevs vid arbete med PECS? Resultatet visar att PECS är ett kommunikationsverktyg med hög evidens men att det finns delade åsikter kring vissa delar.

Alternativa produktionsmetoder vid anläggningsarbeten Kringgjutning av el- och telekabelkanalisation

I dagens samhälle blir det allt mer intressant att spara energi, dels med tanke på miljön och dels föratt minska på utgifterna. Denna energi ska sparas på ett sådant sätt att effekten för användarna blirså liten som möjligt.I denna rapport beskrivs hur ett reglersystem kan byggas för att minska energiförbrukningen hosväxthus genom att reglera belysningen på ett effektivt sätt. Systemet är helt automatiskt vilket göratt användarna inte behöver tänka på styrningen av lamporna alls när väl systemet är uppsatt ochkonfigurerat.För att styra lamporna på ett bra sätt mäts det inkommande ljuset med en PAR-sensor. Lampornatänds och släcks därefter beroende på ljusmängden och även på hur varmt, eller kallt, det är iväxthusen.Styrningen av belysningen sker med en mikrokontroller från Microchip, en PIC18F4620 som ärprogrammerad i C18. Kringkomponenter som portexpasioner, klocka och reläer användes också föratt bygga ett bra reglersystem.Resultatet är att det är möjligt att bygga ett reglersystem med begränsad budget som styr lampornapå ett effektivt sätt.

Windows, RedHat och IPv6 : ett test!

With the huge amount of computers connected to the Internet the IP-addresses are starting to run out. The Internet Engineering Task Force, IETF, have decided that it is about time to exchange the old 32 bits Internet protocol, Ipv4, to a more modern 128 bits protocol called Ipv6. This thesis explores the possibility to install Ipv6 in different operating systems. By testing various operating systems and by set up criteria compare them to each other we give the reader a picture of how the installation is done. We also show which operating systems to prefer if you want to use IPv6.

Med kejsaren som referens : En studie om kejsarkultens påverkan på den skandinaviska aristokratins uppkomst och utveckling

During the three first centuries A.D the cult to roman emperor was practiced over the absolute majority of the known world. It was based on the idea of the deified ruler, where religion was used as a way of legitimizing a social position of an absolute few. It arrived from below but was promoted and spread from above as a way of governmental control. During the same period of time did a new aristocratic social group emerge in remote Scandinavia that eagerly sought new ways to identify themselves and their newly found social standing. With a base consisting of an economic surplus they wanted to create an acceptance for their new way of life and thus in doing so change the very foundation and core beliefs of their own society.The central theme of this study is the cultural exchange that took place between these two cultural spheres and mainly of the effect that the cult to the roman emperor had on the emergence and identification process of the Scandinavian aristocracy..

Pellets - en framtidsmarknad?

With higher prices for oil and increased focus on fossil fuels impact on the environment the heating sector are searching for alternative fuels. Pellets are a quite new product whose production has risen exponential in recent years. Today there are small-, medium-and large-scale users, where the large-scale consumers are the heating sector. The heating sector is mainly using oil to cover the increased demand during cold periods. The purpose of this study is to analyze the potential of pellets if it would replace thermal power plants oil and coal. The study will also analyze the economic impact a conversion would mean for a heating plant and if the pellet is a reasonable substitute. 2008 statistics from the Swedish district heating association were analyzed and a calculation was performed to determine how many tons of pellets is needed to replace coal and oil.

Ett aktivt beslut att renovera passivt : En ekonomisk jämförelse vid upprustning av miljonprogrammetsflerbostadshus

As a result of increased energy prices more and more energy-efficient homes are coveted. An energy-efficient alternative is passive houses, which is characterized by an extremely well insulated building envelope that recovers the heat without the use of radiators or under floor heating. But a passive house requires a higher investment cost than a conventional building project, since it will require more construction materials, training of construction workers, greater land area, and long construction period. But the lower operating cost expects to pay back the higher cost of investment. We therefore question how profitable a passive house is in relation to houses built according to modern conventional building techniques.The aim of our study is to investigate the viability of passive houses compared to convent­ional houses.

Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme

To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.

Flygteknik : Konceptstudie av ett obemannat flygplan

Unmanned aerial vehicles (UAV?s) are nowadays greatly appreciated. The advantage over manned airplanes are great since UAV?s can be much smaller and therefore lighter. The goal of this project is to evaluate the performance of an environmentally friendly UAV using only lithium-ion batteries.

KRÄDD Konsten att balansera Ekonomiskt och Kulturellt Kapital

This thesis aims to describe how a fashion designer should balance art and commerce in order to succeed in the fashion industry. We aim to define the Swedish term KRÄDD, and sort out how a designer or CEO in the fashion business should relate to the term, as well as the balance between cultural and economic capital. We present theories of the origins and fluctuations of fashion, as well as social studies on cultural capital, and brand building. The study is made in a qualitative manner where the empirics consist of interviews with 13 respondents that have different positions in, and experience from the fashion industry, including designers, journalists, buyers, a CEO and a PR-professional. In our conclusion, we emphasize the need for a balance between cultural and economic capital in order to succeed as a fashion designer.

Simulering av vindkraftverk och närliggande elnät vid Risholmen i Göteborg i SimPowerSystems

With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.

Evaluation of RCM implementation process in Vattenfall
Service and Vattenfall, Hydropower organizations: a study and
analysis of its current status

Vattenfall AB is a large producer of electric energy where approximately half of the energy comes from hydropower. Vattenfall Hydropower has got almost a 100-year old history and the company has developed a lot since 1909. After that the number of power plants increased and the competition got more intense, there were higher demands on the reliability. One way to secure the reliability with a good satisfaction at the power plants is to implement a maintenance method named Reliability-Centred Maintenance. RCM is a result of the introduction of the complex aeroplane Boeing 747 in the 1960?s.

Vallfoder till slaktgrisar : effekter på tillväxt och social beteende vid utfodring

The aims with the project were to investigate how forage consumption affect production and pigs behaviour around the feeding. This degree project was designed to follow 48 growing/finishing Hampshire*Yorkshire pigs, from 30-110 kg live weight, fed diets with or without 20 % forage inclusion. The pigs were divided in three groups due to dietary treatment. In the first group the pigs were fed 20 % of the energy in the feed ration by long grass/clover silage (LE) and the remaining 80 % by a cereal concentrate. Group two was fed chopped grass/clover silage mixed with cereal concentrate (HE) in the same amounts as LE.

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