The thesis evaluates a new kind of bearing arrangement in a traction motor that ABB hasdeveloped. Since the arrangement is designed in a new and innovative way it needs to beevaluated to see if it is safe to use. In today?s traction motors, bearings with a big internalclearance (C4-clearance) are used. The basic idea of the new arrangement is to reduce the fitsbetween the bearing and shaft/house.

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

The main purpose of this project was to make a survey of the steam and electricity consumption at Akzo Nobel Functional Chemistry AB and give suggestions of how to minimize them. These three different areas were focused on. First to make a survey of all the most important consumers, second to find the electricity consumption of the air compressors and the amount of waste heat produced from them. The third area was to calculate a model of how much fresh water that is used during a cooling sequence in the water based heating/cooling system of the reactors and give a suggestion of a suitable reuse for this water.The main result is a total survey of the energy consumption in steam and electricity. The survey shows that the second largest group after drying is heating of ventilation which gives big potentials of reducing the total steam consumption if there is a way of being self supporting in ventilation heat.

This project started with an exploration of geometric shapes and textile materials. It resulted in a chair made out of textile bands with different elasticity. The surface for sitting is flat when the chair is not used, and changes in the moment you sit down and gets a new shape. A piece of furniture that adapts to each individual. The chair emphasizes the important relationship between human and product as the person using it becomes a part of the chair for a moment..

Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.

During the period called Little Ice Age (1400 ~ 1900) the climate of northern Europe was in an annual year-basis overall colder than it was before and after that period. The numbers of short, cold and rainy summers and long, bitter-cold winters where often repetitive under the approximately 500-years the period lasted. In Scandinavia, the coldest time during this period is estimated to have started around the end of the 16th century and lasted to the beginning of the 18th century. Trees growing at the tree-line are limited by temperature for their annual growth and hence showing differences of growth during changes in the climate,  a method called dendroclimatology. The variations of growth can be read in the tree-rings either by analyze the width of the ring or by look into the density of the wood and is used to reconstruct past climates.

The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.

Predation is one of many factors that form the structure of the macroinvertebrate community in lakes, wetlands and watercourses. Earlier studies lack an examination concerning how fish- and waterfowl predation affect macroinvertebrates during shorter periods in the spring. I performed an exclosure study in the shallow eutrophic Lake Tåkern which is located in the western part of Östergötland County, Sweden. The experiment was performed during a three week period (1-21 April 2012) when the water temperature was low and the density of migrating diving ducks was high. The experimental cages used included three out of four different treatments; general predation (open cages), bird exclusion (net with mesh size 90*45mm) and no predation (net with mesh size 1*1mm).

This paper gives an introduction to the theory of minimal surfaces. It is in- tended for undergraduate students with some basic knowledge of differential geometry and complex analysis.After defining the concept of minimal surface and giving a brief histo- rical survey, we look at some well-known minimal surfaces and a few of their characteristic properties. The connection between minimal surfaces and harmonic functions is discussed and the Weierstrass-Enneper represen- tation formulas are introduced. We also present Bjo?rling?s problem and give some examples. .

Running water-pathways have played an important roll in Sweden and frequently been manipulated. One profound change was made during the period of logging when streams were cleared from obstacles as big boulders, sharp bends and side-streams. Dams and different constructions gave control of the stream water and the streams became channel-like with a homogen structure. This interference gave problems for many fish populations and resulted in a shortage of feeding habitat, over-wintering habitat, spawning habitat, unnatural flow regimes, sedimentation, unnatural temperature fluctuations. Many of these historical changes of the watersheds are now subjects for restoration, ie., bring back the streams to what we believed it was before the change. However, what once existed in terms of complexity is now gone and difficult toreplace.

The aim of this report was to investigate the economy of passive houses. The work was focused on economy in total and on the economy of different components such as windows, insulation, heat exchanger and the air tightness of the climate shell. No attention was paid on the comfort factor or to the impacts on the environment.Two houses, aspiring to be passive were chosen; A big one and a small one. Hence, comparisons considering the size of the building have been possible to do as well.The comparisons were made by calculating ?break even? between two concepts; passive and BBR- concept.

If one looks at physical planning in Sweden today one can see that while talking about densification of existing development, reduced emissions and careful use of important land, urban sprawl is a fact with development of sheer residential districts in the urban edges and shopping malls in each and every municipality. As sustainable development is an essential goal for physical planning to strive towards, it is worth questioning if the direction of today?s planning will lead to the goal. A sustainable development can be seen as an obvious to goal aim at. In reality the aim means a hard and complex work.

The aim of this report was to do a case study at a geothermal heating system which has been in operation for about 5 years, and study if its performance has changed during this period of time. A literature study about the processes involved was also done in purpose of background knowledge.The tenant-owner?s association Duvan at Petterslundsgatan in Uppsala installed year 1999-2000 a geothermal heating system. The purpose of this installation was that they hoped it would lead to a smaller usage of district heating which would lead to a reduction of the heating expenses for their buildings. The geothermal heating system consists of 19 energy wells and 4 geothermal heat pumps, and it is one of the first systems of that size in the region of Uppsala.