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.

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.

 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.

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.

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.

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.

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.

This essay discusses and evaluates the international currency market in regards to efficiency. To prove the theory that, the difference between expected and actual exchange rates is explained by the difference in expected and actual interest rates and the difference in expected and actual inflation between countries, a model was developed. This model was inspired by the paper of Sebastian Edwards (1982), and is based on three theories; UIP, IS/LM and the Efficient Markets Hypothesis. The model uses 16 regressions estimated from three pairs of curriencies: $/SEK, £/SEK and ?/SEK.

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.

This project investigated the current market regarding wireless net and the communication between the tools used for diagnostics/maintenance and an embedded system. Based on documentation obtained through interviews a demo system was created based on Bluetooth Low Energy (BLE) communication between an embedded system and an Android device.This report intends to describe the tools and methods used in the design of the demo system and the result of an analysis of the BLE communication.Bluetooth Low Energy is an exciting protocol with wide applicability within the industrial field. This project investigated the communicational possibilities between a Smartphone and a Raspberry Pi and based on the results that emerged the conclusion can be drawn that BLE is a protocol with many beneficial applications within industrial IT..

The purpose of this master thesis is to investigate how nearby forests affect the energy production in wind turbines. To reach the purpose a case study is performed on three wind turbines sited on a field in a north-south line at Andersfält in the municipality of Halmstad, Sweden. Approximately 100 meters south of the southern wind turbine a forest is situated. The case study is divided into three sub studies where the difference in energy production, the affect of the forest and a wind meteorology model, WAsP, is studied. The result show that the forest have a significant influence and that the WAsP-model gives an incorrect result of the energy production in wind turbines sited near a forest..

The purpose of this paper is to apply the Dual-Effect hypothesis in Pritmani, Shome and Singal paper (2003), in order to analyze the exchange rate exposure on firms listed on the U.K. market. The study will examine if the foreign involvement of the firm will affect the share price of the firm.In addition to evaluating the Dual-Effect hypothesis in Pritmani et. al. (2003), we will evaluate the effect of foreign interest rates impact on U.K.

The industrial sector accounts for a large share of greenhouse gas emissions. To reduce its negative impact on the environment is crucial in the quest for a sustainable future. In discussions of the industrial sector's impact on the environment guidelines have been highlighted as a tool to assist the industries in their efforts to change the relationship between the consumption of energy and production. This by improving energy efficiency and a shift to the best available technology. During the past 30 years the steel industry has reduced its energy consumption per ton of steel produced by 50 percent.

På uppdrag av Sweco Systems i Umeå har detta examensarbete utförts under våren 2013. Syftet var att undersöka huruvida något av de energiberäknings-program som används på företaget kan anses vara lämpligt vid energikartläggningar av befintliga fastigheter.Inledningsvis utfördes en energikartläggning av fastigheten Odin 12 i Umeå, som i huvudsak utgörs av gallerian MVG. Med resultaten från denna energikartläggning som grund beräknades därefter fastighetens energianvändning i två olika program ? VIP-Energy och IDA Indoor Climate and Energy.Resultaten från den inledande kartläggningen visar att fastigheten har ett lågt behov av fjärrvärme, vilket förklaras av fastighetens höga elförbrukning. Den stora användningen av el genererar stora mängder internvärme som, förutom att sänka fjärrvärmebehovet, även medför att fastigheten under hela året har ett kylbehov.Utvärderingen av de två beräkningsprogrammen visar att VIP-Energy är ett lämpligt program att använda vid energikartläggningar.

The goal of this study is to examine how the market reacts when information about the exchange of a CEO becomes public. It also examines factors such as gender and whether the departure was voluntary or not, discerning if the market behaves differently concerning any of these aspects.To achieve this, the study was performed using an event study. The selection consisted of 48 companies on the Stockholm Stock Exchange, who had during the years 2005 to 2008 underwent a change in leading management. These units were submitted to hypothesis tests, to determine if an abnormal return was attained during the event window. The tests were performed on the units as a whole, and divided up after gender and whether the departure was voluntary or not.The results of the study show no statistically significant abnormal return caused by the announcement of a CEO exchange.