In hydropower plants it is necessary to always have local power supply. Therefore, the plants are equipped with batteries as stationary back up power. Vattenfall Vattenkraft is using lead acid batteries but has been investigating alternatives to replace them. The aim of this study is to investigate the potential of using Li-ion technology as back up power.The study showed that Li-ion batteries have many qualities. The Li-ion technology will decrease the space and maintenance demand.

Målet med examensarbetet har varit att ta fram teoretiskt underlag och en beräkningsmodell. Detta ska beskriva hur kabeltyp, kabellängd, kabelarea samt effektfaktor påverkar spänningsfallet över ett 400 Hz ledningssystem.Mätningar har utförts på två olika kablar som används i det aktuella systemet. En av kablarna var symm­et­riskt uppbyggd med 7 ledare, där respektive fas bestod av två ledare förskjutna 180° från varandra runt nolledaren. För att åstadkomma 115/200V 400 Hz, användes en 90 kVA frekvensomformare. Belastningen som användes var en resistiv, induktiv samt en kapacitiv belastning.

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Parents today can be very stressed at the drop off and pick up of their children, this leads to that they sometimes miss important information that is pinned to the walls for example. Papers has the ability to disappear, a blog collects all in one place. Today, almost everything is digitized.This study has examined what a blog is and how schools and preschools can use it. The blog is used as a communication site for the preschools and school. This exam graduate work is made of three blog analysis, the analysis is made to see if the blogs can help the preschool and school to communicate wiht the parents.The theory I have decided to use in this study is the sociocultural theory.

Introduction and background: The 1990s crisis and the global financial crisis year 2008 shows the same indications that the property market was affected negative. The Swedish Property companies had a difficult time on the market when the crisis led to decreased property trade and financing problems for the Property companies. The Swedish property companies became less attractive on the market and contributed to a drop in prices on investment property.Purpose: The purpose of this essay is to examine if there is any relation between the Swedish Property companies impairments on their investment property and the global financial crisis year 2008.Method: The essay is based on a quantitative study where we examined Swedish Property companies? annual reports. We answered our questions and our purpose from the empirical data that we collected from the annual reports.Conclusions: The study resulted in that we found a correlation between the Swedish Property companies? impairments on their investment properties and the global financial crisis year 2008.

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Eriksson, Simon & Ögren, Andreas. (2011). Vart tar fotbollsungdomarna vägen? En studie om varför 15-16 åringar i Västerbotten väljer att lämna fotbollen. (Where do the football youths go? A study of why 15-16 year olds in Västerbotten choose to leave football) Bachelor Essay in Swedish.

This paper deals with prehistoric charred organic material, interpreted as bread, found in graves and in the underlying settlement at Kalvshälla, Järfälla parish in Uppland. The aim was to categorize the organic material morphologically and with the help of Fourier transformed Infrared spectroscopy (FT-IR) to see whether it was bread or not. Material from 13 graves (dated to Late Roman Iron Age until Viking Age) and 3 finds from the settlement have been analysed. Differences were noted both in shape, porosity and structure. Some of the material has been interpreted as cereal based foodstuff instead of bread due to morphological discrepancies.

Nederbördsmätning är viktigt inom många områden och en relativt ny teknik är enoptisk distrometer som med hjälp av laserteknik mäter nederbördspartiklarnasdroppstorlek och fallhastighet. Syftet med detta arbete var att undersöka hur välThies distrometer stämmer överens med nederbördsmätning från ett vippkärl ochmanuella mätningar från institutionen för geovetenskaper vid Uppsala universitet.Institutionen för geovetenskaper överväger att gå över till denna teknik och därmedbehövdes distrometern utvärderas för olika faktorer som kan påverka instrumentet.Vid jämförelse mellan instrumenten visade det sig att distrometern totalt sett samladein mer nederbörd än de andra mätarna. Det är svårt att avgöra vad skillnaden mellaninstrumenten kan bero på men felkällor så som avdunstning och vätning hos vippkärletoch manuella mätningar kan ge mindre nederbörd. En annan orsak kan varafelkalibrering av datan från distrometern. Inga samband hittades för vindhastighet,vindriktning och typ av nederbörd mellan de tre instrumenten.En vidare undersökning gjordes för droppstorleksfördelningen för att ge exempelpå fördelar med en distrometer.

Kronoparken is a multicultural area with more than 100 different nationalities. Since we know that girls with a foreign background participate less in sport than girls with Swedish background do, we think it would be interesting to examine what kind of thoughts and experiences young girls on Kronoparken has about sport.  The purpose of this study is to examine what the girls think about the activities that are offered today. We also want to examine their thoughts about sport and gender issues.Since the aim is to identify the girl?s experiences around current activities and find out what ideas they have to improve this, we think a qualitative method is best suited. We have chosen to do interviews with two focus groups.

In visual programming the developer specifies her code, using visual tools. Within the range of visual programming languages lay icon-based languages, form-based languages, and diagram languages.Mediator is a multimedia authoring tool that allows the user to create interactive CD-ROM presentations, dynamic HTML pages and Flash projects, without any coding or scripting. The user can create interactivity in her project, using event driven and icon-based visual programming, through a ?drag and drop? user interface. This report intends to determine some of the qualifications of a tool of this kind, as well as its limitations.The report is based on a case study, in which a smaller software application was to be updated using Mediator 9.

Länsförsäkringar in Värmland, Sweden, had during the year 2003 a total level of 6.1 percent of people on the sick-list, which was higher than average in the business (4,5%) and for salaried employees in the private sector (3,3%). The average age of those put on sick-list was 47 years, whish is four years higher than the average for the whole LF-group. The cost for the total amount of people being on sick-list at LF-company (6,1%) was estimated to 1 500 kkr, according to a calculation model coming from Försäkringskassan. For every percent the sick level could be reduced, the company would save 239 kkr. To map out the state of health of each and every collaborator in LF, the company offered all employees to make a health profile at the company's health service, Clarahälsan AB.

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Testosterone is a steroid and anabolic hormone found in all mammals. Previous research indicates that testosterone levels correlates with physical capacities related to physical performance. However, these studies refers only to men and boys. The aim of present study was therefore to investigate the potential relationship between body composition, strength, power and endurance capabilities in relation to blood levels of testosterone and DHEAS in young female football players. Seventeen female elite football (age: 15,4 ± 0,6, body mass: 57,2 ± 7,4kg, height 1,65 ±0,04m) players volunteered for the study.