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2612 Uppsatser om Energy security - Sida 19 av 175

Undersökning av samband mellan MCV och geotekniska parametrar. Analys utifrån fält- och laboratorieförsök på finkornig jord

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Följdeffekter av olika användningssätt för vedråvara : en ekonomisk studie

Since the turn of the millennium a sharp increase in the interest for bio energy has been observed. Important reasons for this growing interest can be due to the fact that fossil fuels are a finite resource. A net discharge of greenhouse gases occur when fossil fuels are burned. The discharge of greenhouse gases are considered to be the main reason to the greenhouse effect. Means of control to increase the use of bio energy has been introduced and, as intended, the use of bio energy has increased. As a result of the legal provisions the ability to pay for bio energy has increased, which the forest industry view as a problem.

Framtidens driftcentral : En analys av den framtida driften av ett svenskt elna?t

Active work to increase the efficiency of energy use is taking place in Sweden and throughout all of Europe. Electricity is an important part in our society?s energy system which means that the electrical grid operators and associated therewith has a central role in this work. Monitoring and controlling the electrical grids are managed from the distribution system operator?s DC, dispatch center.The aim of this report is to examine how the operations in a typical DC on the Swedish electricity distribution network will look like in five to ten years.

Utvärdering av labpilot - flödesbatteri : Experimentell studie

Results have shown that flow batteries may be a solution in the future as an effective and environmental friendly method to an energy storage system (ESS). The technology is reliable and has a high efficiency that comes with low energy losses and a long lifetime. The range of possible fields is suitable for cutting energy peaks in the power grid, by always have a ready and available energy storage that balances the production. By comparing the advantages of flow batteries with conventional batteries it is mainly the fact that they can conserve energy for a long time without being self-discharged thanks to that the storage capacity is in principle endless and limited by the size of the electrolytes tanks that makes them a great energy storage system. The batteries won?t take any damage or decrease in performance when charging or discharging it or if you exhausts it to 100 % and leave it discharged for a long time.

Ett öppet eller slutet Europa. En diskursanalys av EU:s flykting- och invandringspolitik

This thesis focuses on the perception of immigration and refugees in the commonEuropean refugee and immigration policy. It identifies different discourses andstudies their development and interrelated power structures.Using the discourse theory of Laclau and Mouffe, documents from theEuropean Council, the Commission, the Justice and Home Affairs Council andParliament debates are analysed. The study is defined in the time span of 1999-2006, i.e. from the European Council's first agreement on developing a commonEuropean asylum system, following the period up till today.Four discourses are distinguished, focusing respectively on rights, security,European Union's needs, and cultural identity. I use Sandra Lavenex theory ofrealism and idealism to analyse one of the main points in the thesis: There is afundamental schism between the one rights-based discourse, focusing on universalhuman rights, and the three sharing a particularistic focus on immigration as asecurity concern.

Informationssa?kerhetsanalysers verksamhetsnytta : Utva?rdering och fo?rba?ttringsfo?rslag

The importance of good information security and safety grows larger and larger for each day in the information society of today. This concerns citizens, companies and public authorities. At the Swedish Transport Administration, the operation of an information security and safety process has evolved over the years to guarantee that the public authority can be trusted by its citizens, cooperating companies and other public authorities. This responsibility has been assigned to the Information Security and Safety Department (Informationssa?kerhetsavdelningen, ITsa?).In this thesis the aim is to review to what extent ITsa? achieves any business benefits for the Swedish Transport Administration, and to analyze, streamline and come up with solutions to improve their workflow.

Energieffektivisering av två flerbostadshus i Västerås, byggda 1963 : Enerigbehovsberäkning med programmet VIP+

 AbstractThe background for this study is that there were a great amount of buildings constructed in Sweden in the years 1965-1975 in a program designed to create one million apartments in a time-period of ten years. These buildings are now, somewhat forty years later in most cases in very poor condition and the need for renovation is great and urgent. This has become a growing problem and more and more voices are being heard pointing towards the vast and extremely expensive task of renovating these buildings. Lately, it has also been more and more important for buildings to be energy-efficient and sustainable environment friendly.In recent years there has been an atempt to solve these problems by renovating such buildings but at the same time making them very energy-efficient. This is in some cases being done by isolating the shell of the building and changing the ventilation-system and so forth.

Trygghet och säkerhet i offentlig stadsmiljö :

To thoroughly think with safety and security in mind is an important issue in planning of public city spaces. Spaces intended to be available to all inhabitants of a city should have a welcoming appearance. Unfortu-nately, this is not the situation in many pedestrian walkways, parks and such spaces, possibly due to lack in safety and security. This master thesis intend to examine questions at this issue ? what makes you feel safe and what causes insecurity in public city spaces. The safety aspect treats the human psychological and sociological ways of perceiving her milieu and other humans in it, and how the physical shape of her surroundings can affect the sense of safety.

Lärk eller Impregnerat ? en kvalitativt jämförande livscykelanalys av sibirisk lärk och svensk tryckimpregnerad furu

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Vad förvaltningen bör sträva efter : -riksdagspartiernas uppfattningar om de värden som förknippas med förvaltningen

The values politicians relate with public administration are likely to affect the way that they want the public administration to be organised. The purpose of this study is therefore to examine which values Swedish parliamentary parties relate with public administration and more particularly how they emphasise these values.The study is conducted as an analysis of theoretically relevant bills that the government party and the parliamentary parties have introduced to the Riksdag, and reports and statements of opinion from the parliamentary committees. The documents are from the Riksdag´s sessions from 2000/01 to 2005/06. After examining the documents the conclusion can be drawn that the value that is most emphasised during the period is legal security. This might mean that legal security will have more influence on the decisions taken about the organisation of Swedish public administration..

Jämförelse av frånluftsvärmepumpar

In order to reach the environmental targets, set up by the EU, there are many measures taken to make Sweden more energy efficient. In the housing and real estate sector, an installation of an exhaust air heat pump that reuses the heat in the exhaust air in order to lower the amount of acquired energy, is an example of such an action. The recovered energy can then be used for heating of radiators and tap water. This report aims to evaluate and compare three different systems using exhaust air heat pumps regarding COP, degree of coverage and cost savings. This study was delimited to only account for apartment buildings.The theory chapter describes the different conditions and factors that affect a building?s energy balance.

Kvalitetskontroll av trafikmätningssystem ? En studie om noggrannheten hos induktiv slinga, slang, KomFram, video och radar i olika trafikmiljöer

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Analys av hur byggnadens höjd påverkar energiförbrukningen i flerbostads- och kontorshus

This diploma work has been carried out in collaboration with the building contractor Sh Bygg Fastighetsutveckling AB in Uppsala with the intention to investigate how the height of a building affects various energy aspects such as transmission losses, infiltration, and the specific energy usage. Three different reference objects have been studied. The reference objects have been simulated for four different heights in the calculation program VIP-Energy.The results show that an increase in floor number can lead to both advantages and disadvantages. As the number of floors increases, transmission losses per square meter floor area decreases. However, as the height of the building increases, the reduction rate decreases.

Elevers uppfattningar om kunskap, motivation och undervisning kopplat till SO-ämnena

The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.

Den levande policyn

In today's changing environment, an increasing number of companies are realizing thebenefits of analyzing business information and thereby stay competitive. By making use ofdecision support systems, known as Business Intelligence (BI), organizations are expected tocollect and process business data and thus get more out of their business.Nowadays it is not enough for organizations to have access to corporate data inside officewalls, they must also be able to bring the information "on the go", which has been thefoundation for the progress of mobile BI solutions. As the mobility increases and thecorporate data leaves the office, new risks arise, which is one reason as to why manycompanies hesitate at the idea of introducing mobile BI solutions.In this paper we explore two security aspects in the area of mobile BI solutions. Our researchquestion is as follows: How does security aspects affect a company's decision to acquiremobile BI solutions? The survey was conducted through interviews in cooperation with thefirm Optivasys, exclusively dedicated to the BI solution QlikView.A significant part of the theory we studied describes security as critical; however, ourresearch suggests a solution on how companies can manage the security aspects.

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