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 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 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 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.

During the last two decades, technology has developed rapidly. It has become a natural part of everyday life, which we today take for granted. It isn?t until the last few years that technology has quickly become a big part in the school environments. Computers, tablets and other technology is today a big part of the education and teaching.

 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.

Chalmers University of Technology today have numerous computers which are never powereddown, at the same time there is a need for more computation power for researchers.Hence, we have investigated the possibility to use the computers for computing power andsecondly, if there is no work to be done, to put them into power saving mode.We have made a thorough study where we compared different distributing systems andin the end HTCondor was chosen as the best to implement. HTCondor is an excellent systemfor opportunistic use of computing power, i.e. make use of computers that no one elseis currently using. The system is used at several universities around the world with goodresults and would be excellent at Chalmers, where there is a need for such a system.Our implementation shows that HTCondor is well capable of handling unused computingpower. HTCondor can handle most file types that may be run on the system.

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.

AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.

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..