The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.

The increasing oil prices during the last years have made it profitable to use cereal grains as a fuel. When compared with wood, cereals contain higher amounts of Cl, S and ash. The Cl and S content makes the gases from cereal combustion more corrosive than gases from wood combustion. The goal of this master thesis was to find out the variation of Cl, S and ash content for oat grain grown under different conditions. Oats was chosen because in Sweden it's considered as the cereal with the best fuel qualities.

The Kverneland Ecomat and The Ecomat Seeder has been tested in three different field studies. All the studies were conducted on soils with different clay content during 2005 in Säby outside Uppsala. In one of the trial spring ploughing with the Ecomat and spring ploughing and seeding with Ecomat Seeder were compared with conventional autumn mouldboard ploughing and spring mouldboard ploughing to conventional depth (22-23 cm). In this study the quality of the seedbed, the number of emerged plants and weeds, the pentration resistance and the yield were examined. Shallow spring ploughing (10 cm) with the Kverneland Ecomat has shown to be a good alternative to conventional autumn ploughing when growing spring crops. During the season 2005 tilling with the Ecomat resulted in a higher yield than conventional ploughing. In 2002-2005 the average yield for shallow spring ploughing was 4 percent higher than after conventional autumn mouldboard ploughing and 10 percent higher than after spring mouldboard ploughing to conventional depth (22-23 cm). In the other two studies, ploughing to different depth in the autumn with the Ecomat was compared with conventional mouldboard ploughing and stubble discing.

This report presents a method for modelling a computer system from a security perspective. The questions that are going to be treated are:? What defines a secure system and how does the company relate to these factors?? What are the threats today based on hardware/software, human factors and company routines/policies?? What measures should be taken for the organisation to reach a higher level of security for their systems?? How do we develop a method for classification of security and what components should it contain?? What changes are reasonable and necessary with the respect to the company?s resources?The report has been done through interviews and analysis of existing systems on Fla?kt Woods AB. From analysis of material, the aspects judged relevant to the subject and to the company?s needs, have been compiled to a document.

Today cultivation of cereal in Sweden has high costs for establishment in relation to the rest of the world, and if this cultivation will be able to continue, the farmers have to control their costs. It is important to see all costs, not the maximum harvest achieved, but the net result. All farmers have different conditions with respect to soil, direction of the farm and were the farm is located geographically. With the right knowledge and ambitions, we think most farmers could change to reduced tillage. In this paper we have tried to find out if reduced tillage is an alternative for farmers.

Nuclear power plants existences have been well debated since the 70s (Swedish radiation safety authority, 2014). Accidents, risk and presence connected to nuclear power plants have been part of many studies around the world. Recent studies have shown a connection between prices of houses and the distance and presence of nuclear power plant in a surronding area of the house. This paper uses Hedonic price modelling to investigate the willingness to pay for an increased distance to the Swedish nuclear power plant, Forsmark. For the dependent variable selling price was used and the independent variables were number of rooms, living area, other area, lot size, selling year, building year and distance to Forsmark.

It is imperative to provide more information regarding changed conditions resulting landslide events in a future climate. The aim of this thesis is to assess landslide susceptibility in Huddinge Municipality in middle Sweden. The main purpose is to produce a map, to visualize landslide susceptible areas, and to integrate the result with changes in physical factors such as climate change. Also, the thesis aims to analyze anthropogenic factors such as changes in land use and an increasing population in Huddinge Municipality. Methods used are GIS-analyses, interviews with staff of Huddinge Municipality, and field observations.

Due to the climate change natural disasters expects to increase and in some areas the conditions for dissemination of hazardous pollutants from contaminated areas could be affected. Different inventories and mapping has been made to identify areas of risk for flood or avalanche around the country. At the same time inventory and treatment of potential polluted areas (MIFO objects) is progressing. In Ljungans run of area in Västernorrlands county is a exposed area due to the amount of clay and silt in the ground that are sensitive in the context avalanche. The area has also a lot of MIFO objects and risks of flood.This essay aims to investigate what data material that is available regarding MIFO objects, flood- and avalanche risks in Ljungans run of area in Västernorrlands county.

Large companies in today?s business environment are to a great extent depending on their credit score by rating institutes like Moody?s and Standard & Poor?s. There is however indications that these big institutes are not always rating companies accurately. This is why this thesis aims at developing a new credit rating model, CRITA-Score, with the objective of determining a company?s financial health more accurately.

Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.

Syftet med examensarbetet har varit att studera kol i mindre vattendrag med hjälp av jämviktsmodellering i PHREEQC. Fokus har varit dynamik av löst icke organiskt kol (DIC) samt att förstå hur mycket koldioxid (CO2) som avges från mindre vattendrag och om den mängden har signifikant inverkan på den globala kolbalansen. Med hjälp av provtagen data från Krycklans avrinningsområde år 2003-2007 och 2009 har modellering av DIC och pCO2 utförts med målet att se förändring både över säsong och nedströms i ytvattensystemet. För att utvärdera modellen har tillhandahållen data över uppmätt pCO2 använts. Målet var att jämföra modellerade och tillhandahållna pCO2-värden för att se hur väl modellen kunde beskriva verkligheten och om den fungerade bättre för någon plats eller under vissa delar av året.

A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.

This study examines how the local rescue services relate to the brand of the rescue service and the concept of brand management. To understand the attitudes against the brand and brand management, empirical data, theoretical modelling of brand and current laws have been discussed together in a try to get an overview how the rescue services practically works with the brand. The study results are based on a questionnaire survey and qualitative semi-structured interviews. The survey was sent to employees working with the communication of the rescue service. The interviews were held with two employees working with the communication of the rescue service and two fire chiefs.

Several studies have analysed the relationship between Normalised DifferenceVegetation Index (NDVI) and radiative surface temperature. A main goal for moststudies have been to find the best method for carrying out land cover classificationsand to study land cover changes, based on a combination between the twoparameters. Since atmospheric components have a significant influence on bothparameters, most applications were based on multi-temporal data. The quality of theindividual values in such a combination is improved, but the biophysical justificationis uncertain. This study presents a different method, based on only the combination ofvalues that have been registered the same day and about the same time of the day.125 daily images of NDVI and 250 images of radiometric temperature were used inorder to analyse the relationship between (1) NDVI and radiative temperature and (2)NDVI and relative temperature difference between early morning and mid-day.Results between NDVI and radiative temperature show a significant negativecorrelation on areas where a distinct growing season develops, and a strong positivcorrelation where vegetation is abscent throghout the season.

During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland.