The southern part of Sweden, Skåne, is frequently exposed to storms causing great damage to Norway spruce (Picea abies L. Karst.) stands. A storm during the winter 1999/2000 raised the attention of the problem. A lot of forest owners got large areas of spruce stands wind thrown during this storm. Can naturally regenerated birch (Betula sp.) be an alternative on these wind-exposed sites? This was the main question I was facing when discussilig the problems with Esben Möller Madsen, Söderåsens forest district. The aim of this master thesis was to present an economic analysis of Norway spruce versus birch.

The aim of this work is to demonstrate how the net present value (NPV) at the time of the first thinning depends on the spacing after pre-commercial thinning, and show how net value from first thinning in same stand is influenced. This study is performed with models based on non-distant dependent growth models for single trees. Two different growth models have been used, one for cleaning (pre-commercial thinning) and one for thinning. The first one yields stem density distributed over diameter classes. In the second one, (the thinning model), it is possible to choose when thinning should be done, the thinning method, thinning grade and numbers of thinning.

In the last few years people have become more and more aware of how humanity is affecting the climate. In the direction of reducing the greenhouse gases is to design engines with higher tensile properties and reduced weight, in order to achieve lower fuel consumption and cleaner fuel incineration in today's truck engines.In order to achieve these requirements it?s necessary to increase the combustion pressure in the engine. This requires higher tensile properties and high thermal conductivity of the engine material. The department of Component Technology at the University of Jönköping in collaboration with Volvo Powertrain AB, Scania CV AB and DAROS Piston Rings AB has been commissioned to develop this material and to find knowledge of material properties used in truck engines and piston rings used for marine applications.The purpose with this work is to analyze the tensile properties of a series of cast iron, cast under different metallurgical conditions.Four different series of cast irons have been analyzed from four points of view, carbon concentration, nodularity, amount inoculation and cooling rate.After the tensile test all specimen data was analyzed in a mathematic calculation program called Matlab 2006a.

AbstractPrevious studies have shown that wild smolt have 2.5-4.5 times higher survival rate than smolt grown in culture and that starved reared smolt behave more like wild born smolt. The purpose of this project was to study whether there are differences in migration patterns and survival during migration to the coast between wild and reared smolt and between different types of reared smolt.In 2009, 25 smolts in three different groups were tagged with acoustic transmitters: Wild Born, conventionally reared 2-year and 1 ?year old smolt. For the 2010 trial there was also added a group of reared 2 ?year old smolt that were starved before release.

Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.

This report will show the energy usage of Hotel Princess in Sandviken, Sweden. When the hotel changed owner an examination of the hotels heating, ventilation and sanitary systems were done. The report showed flaws in the ventilation system, and is why the new owner wanted a closer look at the energy use of the hotel. The original building was built in the 1930s and two major extensions have been built, one in the 1950s and the most recent in the 1980s. An assumption made is that the building parts were built to the restrictions during the time. Activities on the hotel include sleep over, conference, night club, massage and swimming in the hotels pool section.

Four different kinds of filter-materials with reactive surfaces have been studied concerning their capacity to absorb heavy metals in leachate from a municipal waste deposit. The heavy metals studied were: lead, cadmium, copper, mercury, chromium, nickel and zinc. The leachate contains high levels of dissolved organic carbon (DOC) and has a high pH-value along with a high buffer capacity. These characteristics of the leachate make it difficult to remove pollutants and require efficient filters. The filters that were examined in the report are blast-furnace slag with CaO, sand covered with iron oxides, olivine and nepheline.

AimThe purpose of this study is to compare the level of activity between playing wii Sports Tennis and wii Sports boxing, and the usual sports, and to see how the two variants are perceived.Issues:- How much strain ratio and energy consumption it gives to exercise wii sports compared with the playing of sport for real?- How do the test participants experience the different tests?- How are the two wii sports games against each other in terms of activity and fitness in the school environment?MethodThis is an experimental study in which 10 test participants (5 men and 5 women) have carried out four different physical tests. The tests consisted of either playing an exergame or playing a sport for 25 minutes. Physical activity was measured during the test using a heart rate monitor. All test participants completed all tests in the same order.

The aim of this study was to investigate whether a direct shift inpostural alignment results in changes in voice source characteristics. Ninemales with untrained voices were recorded standing in ideal posturalalignment and in the deviant postures swayback and kyphosis characterizedby extended hips and a slump back respectively. The voice source wasderived from the audio signal by inverse filtering. The parameters pulseamplitude, maximal flow declination rate, level difference between the firstand second voice source partials, closed quotient and the normalizedamplitude quotient in relation to subglottal pressure were compared betweenideal postural alignment and swayback and kyphosis respectively. Resultsindicate an impact of changed postural alignment on the voice source.Swayback posture gave significantly less pulse amplitude and maximal flowdeclination rate and significantly higher subglottal pressures thus resulting ina less effective phonation.

With increased milkproduction in our dairy cattle, comes a risk for a reduced fertility. Studies performed on animals and humans have shown that it is possible to manipulate the oestrous cycle through exposure to pheromones. This means that pheromones could potentionally be used to make reproduction more efficient. To evaluate the bioactivity of the substances in question, there is need for a bioassay. In insects, pheromones can induce a changed cardiac activity.

Transmission of reactive power is well known to cause active power losses. Thus, newcomponents who can help minimizing these expensive reactive power flows are ofgreat interest to the power distribution companies. ABB Corporate Research hasdeveloped the first electronic power breaker. One possible application for thisbreaker is transient-free switching of capacitor banks. This could prove a usefuldistribution voltage complement to the switch-sync technique, mainly applied to transmissionvoltage level.

This master?s thesis will examine the concept of ?fixed establishment? in VAT-law. The concept can be found in the new EC-directive on the common system of value added tax, however it has existed for thirty years in previous directives. Despite this, the legislator has never provided a proper definition of the concept. Its meaning has therefore evolved through the case-law of the ECJ.The Court has put forward a number of criteria which are all to be met if a fixed establishment is to be at hand.

Unemployment amongst Swedish citizens is higher within the group which falls under the designation foreign-born. The aim of this thesis is to examine which municipal factors that can explain the differences in unemployment amongst foreign-born relative to native born.The empirical models are examined with both cross-sectional data for the year of 2010 and panel data for the years of 2002-2012. The examination is implemented through a linear regression analysis of the type Ordinary Least Squares (OLS) and Fixed Effect regressions. A theory section will be presented where the theory on Non-Accelerating Inflation Rate (NAIRU), theories on discrimination and country-specific human capital are illustrated.The result from the cross-sectional data shows that the amount of foreign-born, the level of foreign-born immigrated from Nordic countries have a significant negative effect on unemployment amongst foreign-born. The general unemployment shows a significant positive effect on the unemployment amongst foreign-born.

There are several ways to identify individuals with dry mouth, but there are few studies made in which the different methods have been compared with each other.The aim of this pilotstudy was to compare different methods for identifying individuals with dry mouth. Fifty individuals aged 50 to 75 years were included in this studie. These where randomly chosen among patients at the dental clinic at Kristianstad University College. Four different salivary measurements were conducted: 1) collection of unstimulated saliva, 2) collection of stimulated saliva, 3) the so called ?mirrortest?, and 4) analyse using cottonrolls.

This bachelor thesis is intended to gather the knowledge and experimental data on the winter wheat crop production relevant for Swedish conditions, with focus on sowing time, row spacing and seed rate. This essay is a literature study with a minor component based on interviews with farmers producing winter wheat. The work is divided into a background part where basic knowledge of winter wheat physiology, development and environment interactions are described and one part where results of field trials studies are presented. Optimal date of sowing winter wheat depends on annual weather variations. Because it is difficult to forecast the weather the choice of sowing date should be based on weather statistics, production experience and previous results depending on sowing date.