Dokumentet är ett resultat av studier gjorda under kursen Kandidatarbete I Datavetenskap. Arbetet utforskade, genom fallstudie, två egenskaper av distribuerade informationssystem och relation mellan dessa: säkerhet och prestanda. Målet med fallstudien har varit att belysa nackdelen med användning av Secure Socker Layer (SSL) dvs. dess effekt på hastigheten och fördelen med SSL, dvs. SSL:s roll i informationssäkerhetsarbetet.

A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce.

E-business innebär att företag använder Internetteknologier eller nätverksteknologier för att skapa större affärsnytta i deras affärsprocesser. För att kunna genomföra automatiserade affärsprocesser krävs att de olika system som används är interoperabla, d v s kan kommunicera och fungera ihop på ett effektivt sätt. Målet med Web Services är att skapa hög interoperabilitet, vilket gör denna teknik lämplig för e-business. Företag kan specialicera sig på att skapa specifika Web Services. Dessa Web Services kan sedan vara byggstenar åt andra företags tjänster. Det krävs då att Web Services kan integreras på ett bra sätt så att de verkligen bildar en affärsprocess. Därför är även frågor kring hur integration mellan Web Services ska gå till, viktigt ur ett e-bussiness perspektiv. Det vi kommit fram till är att det går att minimera integrationsproblemen genom att anvä nda de mest standardiserade protokollen och följa vissa riktlinjer vid skapandet av Web Services.

Purpose: The purpose is to examine more closely why the achievement of the environmental goals is so low. To within the thesis work to make this as interesting and with as good quality as possible, especially the environmental quality goal Reduced climate impact, but also Natural acidification and Protective ozone layer, has been chosen to be studied further. Method: A qualitative method and text analysis has been applied. Intervention theory, as Vedung 2009 describes, is used as an intellectual backbone and as a help to structure the essay. The three environmental quality goals correspond cases, or units of analysis. Analysis: The fulfillment of the respective environmental quality goals is analyzed according to its goal, policy instruments, implementation and its effects. To this some of the problems are analyzed that exist on the path to achieve the goals.

Deep litter is a system for animals kept in separate stalls, loafing and bedding in wind shelters. The litter can consist of different bedding, like straw and peat. The system is allowed to build over and to ensure optimal proportions it is necessary to add new straw regularly and to have good conditions. Important conditions are aerobic state, humidity, amount of organic substance and acceptable temperatures in the litter. The micro organisms are depending on temperature for their living conditions and to get the bottom layer in the litter to start burning.

I have through a case study looked on a milkingfarm in Dalarna and been counting on what it would cost to increase the silagestorage. Today they have to little capacity on the existing towersilo because they built a bigger farm with more cows. The reason is that two families decided to start having the production on one farm together and moved all animals from one of the farms to the other farm. So for that reason I have looked on the costs to build a new towersilo or levelsilo. The goal has been not only to look at the buildingcost but also which operatingcost that is included with the different alternatives. I have taken tenders from two different towersilocompany, Bjurenwall and Svenska Neuero and taken tenders from Abetong for a levelsilo with roof and one without roof. The overall feed requirements on the farm is on 240 tonnes dry extract and the old towersilo hold 110 tonnes dry extract so the need for a new foundation is on 130 tonnes dry extract. I have through cost estimate been counting on the specific buildingcost for each buildingaltenative.

The aim of this study is to describe how a theme about vitamins and analytical chemistry can be planed and implemented in a summer research school managed by AstraZeneca. The description of the theme is intended to be used as an instructor?s guide to upcoming summers-research-schools with the same theme. The students, which participated in the summer school of 2007, went to upper secondary school. During the summer school they were going to investigate the content of vitamin C in different fruits and vegetables.

Most of the portable electronic devices use a battery as a primary power source. Nowadays, when the applications are becoming smaller and smaller and more power efficient, the designer needs to concentrate more on reducing power consumption, using secondary power sources and introducing power storage devices. Multiple power source availability and a power storage device on the board will make the applications much more useful and efficient in everyday use. This thesis proposes a power supply unit (PSU) for wireless sensor platforms which is capable of supplying a sensor node with energy from multiple sources, as well as status information from the PSU. Present power storage devices, like electric double-layer capacitors (EDLCs) and batteries, have become more and more common as their characteristics have developed.

This pre-study investigates the possibility of U-value measurements through an acoustic method. A hypothesis about an acoustic model built on acoustic theories combined with U-value theories is presented to answer the questions: ? Can U-value theory be combined with acoustic theories? ? Can the coefficient of heat be affirmed trough an acoustic measurement? The idea for this dissertation begun with a logical idea in mathematical similarity, between the coefficient of heat transmission units and sound intensity units. The U-value theory is based on assumptions such as initial resistance for inner walls and initial resistance for outer walls. The resistance in the material is interpreted through sound intensity theory. The argument is built upon mass law theory, which means if the frequency or thickness of the material layer doubles it implies an increase of sound reduction by 6 dB.

The increasing threat of climate change has led to a increased need for models to predict future climat. In these models the changes in the soil carbon pools due to changes in microbiel degradation of the organic matter can lead to both positive and negative feedback-effects. There is however a lack of consensues on the temperature respons on degradation soil organic matter. This paper aim to give a better understanding on the factors controlling the temperature respons. The factors studied were the carbon substrate qualitity and the physiological status of the microorganisms.

Denna studie undersökte om så kallad ?Single layer centrifugation? (SLC) genom en silanöverdragen silikat kan selektera spermier med bättre kvalitet. SLC är en metod för att separera spermier med bra kvalitet från andra celler och seminalplasma genom att utnyttja deras olika densitet.Egenskaperna hos spermier varierar mellan arter och därför även möjligheterna att spara och förvara spermier. Utvärdering av spermiekvalitet är viktigt för att förutsäga den fertila förmågan och även utvärdera påverkan de olika processerna som spermierna utsätts för. I denna studie har spermiernas morfologi, motilitet, membranintegritet och akrosomintegritet undersöktes.Ejakulat från sex hundar av olika ras och ålder användes.

This master thesis has been done in cooperation with Sweco Viak AB in Sundsvall. The aimwith the project is to investigate the purifying effect of percolation filter due to iron andmanganese. The overall goal was to investigate how the parameters surface load,sandfractions, and burden time affect the purifying effect. The expectation is to optimize thedesign and find a demouldning of the filter that gives sufficient purifying with a highersurface load. As an attempt to accelerate the curing of the filter, experiments with a layer ofsand which surface has been covered with manganese ore (MnO2) on top of the filter havebeen done.As test filters 10 L bars were used and the experimental work was performed at thewaterworks in Hassela and Munkbysjön.In Hassela different sandfractions were tested.

Denna studie undersökte om så kallad ?Single layer centrifugation? (SLC) genom en silanöverdragen silikat kan selektera spermier med bättre kvalitet. SLC är en metod för att separera spermier med bra kvalitet från andra celler och seminalplasma genom att utnyttja deras olika densitet.Egenskaperna hos spermier varierar mellan arter och därför även möjligheterna att spara och förvara spermier. Utvärdering av spermiekvalitet är viktigt för att förutsäga den fertila förmågan och även utvärdera påverkan de olika processerna som spermierna utsätts för. I denna studie har spermiernas morfologi, motilitet, membranintegritet och akrosomintegritet undersöktes.Ejakulat från sex hundar av olika ras och ålder användes.

Problems: How is the purpose of the swedish limited liability company to increase the wealth of its shareholders given in swedish corporate law? Based on which legal and economical grounds has this regulation been made? Which problems may occur when the purpose of the company is to maximize the wealth of its shareholders? Which strategies can be used to prevent the problems that may occur? Should the purpose of the company be to maximize the wealth of its shareholders? Purpose: The purpose of this thesis is to evaluate whether a limited liability company primarily shall aim at maximizing the wealth of its shareholders or not. Delimitations: This thesis only attend swedish limited liability companies. It also only treat swedish corporate law de lege lata. The thesis focus on larger commercial companies which shares are widely spread.

Inside the south Swedish national park Dalby Söderskog, wild boars (Sus scrofa L.) have been visiting since 2010. The presence of wild boars has earlier been proven to impact both soil and vegetation characteristics, both positively and negatively. Still, there is a lack of knowledge regarding the rooting effect on the vegetation in deciduous forest within the native range. In this study, I have compared the field vegetation collected before and after the invasion of wild boars in 74 permanent experimental plots. More specifically, the study aimed to qualify the effect of wild boar rooting on cover ratio, species richness and species composition in a temperate deciduous forest.