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363 Uppsatser om Stationära värmeförluster - Sida 14 av 25

Värmning av avloppsvatten med spillvärme för att förbättra kvävereningen -Temperaturens inverkan på kvävereningen

The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.

Helandet av Stockholms sår : En analys av projektet Västra City

Over the years, what people have considered as the center of Stockholm City has gone from the medieval Stortorget in Old Town to the contemporary Sergels Torg. But more recently it has become unclear how the area really works. It is difficult to say where the actual central part of Stockholm lies, because while the Central Station is where the majority of people arrive into town, it is not necessarily close to Sergelstorg (considered the center of town) or other attractive commercial areas. There's also another issue with where the center of Stockholm is located. The railways and roads running along Klarabergs Viaduct acts as a divide between the areas of Kungsholmen and Norrmalm; these rails, roads and water separate the two areas from each other. In response to this problem of area division, a plan is being made to construct a new district near the center to mend the gap between the districts. The idea is that the center of Stockholm city will become more lively and attractive. The plan includes building new housing, commercial areas and a larger terrace called Mälarterrassen. In addition, improved mobility within the area is being planned by having better public transportation lines like City banan and tram named Spårväg City construction, as well as more pedestrian areas shall make the area become a district to thrive in.How the area will actually operate in the future is still unclear and many questions still exist about how the area will be able to compete and, above all, integrate with the other districts. The parts considered to be most important for the area is the scale of residential property and an attractive area that keeps people in the area and to encourages them to pass through the area. Perhaps the best solution would be to have something special planned in this area that can attract people in the community ? a city park, for example?.

Komponentuppdelning av elnätetpå lokalnivå

Sweden will, in accordance with the EU-directive 2003/54/EC, move from post-regulating the electricity power grid-tariffs by using a fictitious grid, to a regulation in advance which uses the actual power grid as a starting point. For this purpose a component breakdown of the grid needs to be made to determine the value of the network and by that the tariff price that is reasonable for the network business in question to charge.The primary breakdown criteria is the voltage-level and type of region. Voltage-level is crucial for the cost and complexity of a grid-part, because the higher the voltagelevel is, there are more and stricter laws and rules to follow. This work is limited to the distributionpart of the grid, in other words voltage levels from 20 kV and below.The type of region is crucial to the type of components you can and want to use. In city environments both overhead-wires and independent substations are undesirable for both practical, safety and aesthetic reasons.

Alternativa stråbränslen i växtföljden :

The purpose of this report is to find out which crops, that are good for strawfuel, and can be grown i the area around the city of Lund. The background of this report it that Lunds energy is planning to bild a biofuelheated thermal power station in Örtofta outside of Lund. I have in the report limited me to the crops hemp, whole crop (triticale), reed canary grass, elephant grass and jerusalem artichoke. I have through a documentary research checked the crops, cultivabillity in the south of Sweden, and how they should fit, in the Scanian crop sequence. Hemp is an annual crop which probably could manage in the Scanian crop sequence. Whole crop often triticale because of it´s high yield and low rate of shed seed. Could also fit into the crop sequence of crop in Scanian. Triticale is annual, and could be grown at the same kind of fields as used to wheat, whith is why it would be possible to grow it in Scania. Reed canary grass is a reedlike grass that is easy grown at most soils.

Krylbosmällen

Syftet med denna uppsats var att utifrån Hadenius och Weibulls synsätt se hur en händelse blir en nyhet och ur ett historiskt perspektiv studera hur Krylbosmällen blev en nyhet i tidningarna. Syftet var även att se vilken teori tidningarna hade om orsaken till Krylbosmällen. För att besvara syftet användes en kvalitativ och en kvantitativ metod, där jag undersökte fem olika tidningar och litteratur. När andra världskriget startade förhöll sig Sverige neutrala mellan de västallierade och Tyskland och deras allierade. Efter påtryckningar från Tyskland ingick Sverige ett transiteringsavtal med dem.

Borrning och gängning av laxkilar till vågkraftverk med industrirobot

To make wave power more competitive on the market Uppsala University leads projects that examine how to accomplish better efficiency in the production. One of these projects is described in this report and examines whether it is possible to make the production of dovetails more efficient by using an industry robot of type ABB IRB6000 S3 M91. This project is using an already presented working method, from a previous project, which involves that the robot picks up the dovetail and moves against fixed cutting machines where the dovetail will be drilled, threaded and milled. Drilling and threading are the sub operations that will be examined in this project where experiments are made with the presented working method and with equipment from Uppsala University.Experiments show whether it is possible to drill the holes in the dovetail within specifications by using the specific robot and the presented working method. The threading operation is examined theoretically if it is possible to accomplish by using the same working method.

Dimensioneringsberäkningar av medföljande jordlina i kabelnät

Mellanspänningsnätet består till stor del av markförlagd kabel. Praxis hos Vattenfall är att förlägga medföljande jordlina tillsammans med kabeln. Denna studie tittar på frågeställningen om vilken dimension som ska användas på medföljande jordlina.I studien kartläggs distributionsnätets uppbyggnad utifrån de ingående komponenternas bidrag till jordfelströmmar. Överslagsberäkningar används för att lösa uppgiften.Uppdraget var att undersöka vilken dimension som erfordras på medföljande jordlinan i mellanspänningsnät, (10-20kV) för enkel- och samförläggning. Studien rör anläggningar med kortslutningsström på högst 16 och 20 kA.Beräkningsmetoderna utgår från kända felströmmar och impedanser i kablar och stationer.

Ambulanspersonals uppfattning om fysiska tester och fysisk träning inom ambulanssjukvården

There is no standardized test to control the appropriate physical ability in the Swedish ambulance service. The county in question does not perform annual physical tests. A project has been going to develop science-based physical tests, designed for the ambulance service. The research has resulted in the Aasa-test.Objective: The aims of this study were to examine the ambulance staff perception of the Aasa-test relevance, introduction of annual tests and the importance of their own physical training in relation to ambulance work.Method: A quasi-experimental study with a comparative design has been conducted. Aasa-tests were conducted in 41 randomly selected staff at an ambulance station in central Sweden.

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.

Skattning av byteskostnader på den svenska marknaden för pensionsförsäkringar

Gender equality and gender equality work is relevant for today's working life, and previously male-dominated occupations may be increasingly under pressure to become more equal. This paper aims to explore and understand how the firefighters at a station are experiencing gender and gender equality in rescue services.Using theories of how sex is done, how a power perspective and a structural approach can show men's and women's different conditions in an organization, and theories that are more specific to gender and change management the firefighters talk about gender and gender equality are analyzed. Essay results were collected through interviews with seven firefighters and then analyzed and interpreted with the help of theories.The analysis shows that there is a perception among the firefighters that men and women are biologically different and that required physical strength legitimizes the exclusion of women. Inequality is seen as something natural and by pursuing an active gender equality women are given unwarranted benefits. When physical strength becomes a legitimate reason for exclusion, the responsibility for gender inequality is put on women and that women don?t have what it takes.There is also a resistance against gender equality analyzed in the paper, and it's stated opposition seems to be directed against the management's way of recruiting women.

Del projekt inom ClampCal - Utvärdering av mätmetoder för temperatur, viskositet och densitet samt röregenskaper

The dissertation were performed on SP, Technical Institute of Sweden. The dissertation were carried out on the measurement technical department, this dissertation is a part of a bigger project, project ClampCal. One of SP?s returning assignments are flow-measurement. When flow-measurement is performed, the flow has to be stopped so that a meter can be installed in the pipes where measurement is going to take place. At every stop there is time delay in the flow which causes the customers to loose money. This is why SP wanted to find a better solution so that measurement can be done without any stops in the flow. Usage of a so-called Clamp-on meter was considered, but since the measurement uncertainty is too large it takes some investigation on the parts where the largest uncertainties occur and thus find a solution that can diminish the uncertainty as much as possible. The parts that were considered to have an opportunity to reduce measurement uncertainties were the fluid temperature, its characteristics and the pipe geometry and its characteristics. For the fluid temperature a Pt100-sensor with four different radii for various pipes was used.

Manure evaluation in dairy cows :

Manure evaluation has been suggested as a cheap, fast and easy method which can give information about the digestibility of the ration, the function of the rumen, where in the gastrointestinal tract the feed is digested and the health of the cow. An experiment was conducted to study how manure evaluation could be used as a management tool in Swedish Dairy farming. Manure was collected from cows on Kungsängen Research Station and from 9 other farms. The manure samples were analysed for dry matter, ash, starch, pH-value and particle size (wet sieved). Also, the consistency of the manure was determined on a 5-point scale and the colour and smell were noticed. Penn State Forage Particle Separator was used for determining the particle size of the roughage.

Ökad kapacitet i Stockholms kollektivtrafik - Kan T-Centralen med enkla finansiella medel öka sin kapacitet

By conducting interviews, studies as well as scanning the current scientific landscape, this paper examines the opportunities of increasing current capacity within the public transportation system in Stockholm with simple financial means for the benefit of the travelers. The paper focuses on the central station of the subway system and how adjustments of processes carried out in relation to the turnstiles could increase performance within areas of interest, given the preferences of the travelers. The theoretical framework of the paper includes models from the field of capacity management as well as theories related to the pedestrian behavior. Applying these theories and models to the collected data, the paper derives some main conclusions. First of, people using the public transportations system, and especially the subway, consider speed and dependability as the most important performance objectives for the caretakers of the public transportation system, SL and MTR to master.

Underlag till energieffektiviserande åtgärder i nätstationer

Umeå Energi are working towards a goal, that in the year of 2018, they will be completely climate neutral. As a part of this, one target is to reduce their grid losses by 4 % of the 2012 level, which corresponds to an overall reduction of the grid losses of just over 1.7 GWh. In many residential areas, the distribution grid is designed and rated for electric heating as the heating in the houses. As many of the houses later has been converted to other types of heating, their electricity use has decreased and the total power output from many of the secondary substations has decreased significantly. Because of this, many of these stations today are well oversized, which in turn means that the energy losses in these stations are unnecessarily high.In this degree project, 25 secondary substations have been studied, all located in residential areas in and around central Umeå.

Konststycket

Projektets utgångspunkt är ett nytt konstmuseum i Uppsala, i området bakom Uppsala centralstation, som nyligen genomgått ett ansiktslyft.Museets långsmala karaktär har hämtats från det intilliggande godsmagasinet och från tomtens form. Genom byggnaden har ett diagonalt stråk öppnats, för att ge möjlighet åt fotgängare att passera genom byggnaden och för att skapa liv och rörelse på platsen.Genom fönstren i passagen kan förbipasserande få en skymt av vad som händer inuti muséet. I passagen ligger museets entré, den pedagogiska verksamheten och ett kafé för allmänheten.Museets fasad är inspirerad av den arabiska mashrabiyan. Byggnaden har fönster längs hela fasaden, som i sin tur är täckta av skärmar tillverkade av sträckmetall. Ljuset tillåts komma in i byggnaden samtidigt som sträckmetallen täcker fasaden och bevarar något av museets hemligheter för förbipasserande.Museets inre väggar består av massiva betongskivor, placerade i ett rutnät som fått sin riktning av passagen genom huset.

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