A growing number of cities and municipalities in Sweden begin to work with city models in 3D. For the most part the models are used for visualizations of ongoing planning processes, but also for the analysis of noise, shadow studies and environmental disaster simulations.Gothenburg continues to develop the use of 3D maps in municipal operations and is demanding a way to create building elements (walls), which generates in 3D buildings, from roof constructions that are mapped from the primary map. A method has been investigated in the present study. The results are then presented as a 3D model of buildings, along with a terrain map that will facilitate the localization of the area. The created 3D buildings are then compared with roof-data from the primary map to see how well they harmonize with each other.

A cars powertrain consists of everything that is needed for its propulsion. The components in the driveline that transfer the power from the engine to the driven wheels are not absolutely stiff, hence they will wind up due to the torque and act as torsion springs. If you suddenly demand a bigger torque by stepping on the accelerator pedal, a so called tip in manoeuvre, and that torque is acquired from the engine as quickly as possible, the driveline will not be able to transfer that fast torque change due to its weakness and as a result it will start to oscillate. These oscillations will be transferred to the driven wheels and make the car to accelerate jerkily which will be experienced as uncomfortable by the passengers. Furthermore, there is a backlash in the driveline that will make the weakness in the driveline even more excited than it should have been if the backlash did not existed.To avoid too big problems with these oscillations there is a control system that controls the demanded torque.

During cold winter days it is likely that people in buildings with older windows or high glass facades experience thermal discomfort due to cold air down draughts. Earlier work has been aimed at finding analytical methods to predict the speed of the airflow in a room and in practice heating appliances are often placed beneath the windows to reduce the draught along the floor. In a study from 2012 Mohammad Parchami developed a method for estimating the required heating power to counteract the downdraught with such heating appliances. In this study, Computational Fluid Dynamics (CFD) was used to evaluate the usefulness of Parchami?s method and also to examine the potential of adapting the depth of the inward window sill as a means of decreasing the down draught.

This thesis work is the last part of the Master of Science education inmechanical engineering at KTH, Stockholm.The aim of this project was the development of a Multi-zone modelfor NOxformation in Diesel engines. Because of the stringent emissionlegislations, great effort is made to decrease the fuel consumption and theharmful emissions of internal combustion engines. Computer simulationsplay a decisive role in this context because they substitute the expensiveand time-consuming laboratory tests.The model is based on a multi-zone approach and uses the wellknownExtended Zeldovich Mechanism which gives a relation to calculatethe NO formation rate using the concentration of different gas speciesinvolved in the process.All the most important phenomena involved in the Diesel combustionhave been modelled. A special attention is then paid to the equilibriumconcentration calculation; this is a significant part of the model whichstrongly influences the following steps.A Simulink model has also been developed. This second version isbased on the previous model and it is made especially to allow theconnection with other external softwares, GT-power in this case.

In recent years, global organizations safeguarding financial stability has started to track commercial property markets. One of the reasons for this refers to the fact that commercial property constitutes a large share of bank lending. Simultaneously, bank exposures to commercial property are extensive and risky since collateral values are strongly correlated to borrowers cash flows. Since banks are viewed to play a key role for financial stability, studying the relationship is well motivated. To better understand how commercial property markets interact with financial stability, this paper develops an econometric model for studying the commercial rental market.

Syfte med examensarbetet har varit att upprätta en grundvattenmodell överEnköpingsåsen med hjälp av programvaran MODFLOW för att därefter försöka skattagrundvattenmagasinets parametrar. Parameterskattningen utfördes med detmodelloberoende programmet PEST. Parallellt med detta gjordes även enpumptestutvärdering av dessa parametrar där typkurvor passades till en tidigare utfördprovpumpning av akviferen. Därefter jämfördes dessa båda metoder. Vidare utfördesäven en känslighetsanalys av grundvattenmodellen i MODFLOW för att försökalokalisera nya undersökningsplatser.Grundvattenmodellen uppfördes över Enköpingsåsen i och kring Enköping.

District heating covers most of the residential areas and industries in the twoneighbouring Swedish municipalities Nyköping and Oxelösund. In Nyköping,Vattenfall AB Värme produces heat in a bio-fuelled CHP plant. In Oxelösund,waste heat and use of waste gases from the steel production at SSABOxelösund is the basis in the district heating system.This report examines the environmental consequences of a connection betweenthe two district heating systems. A broad system approach is used and the focusis on environmental effects in the system.A system analysis has been performed on the result of simulations of differentheat and electricity production alternatives. The alternatives simulated wereone where Vattenfall Nyköping covers the base load in the joint district heatingsystem and two where the power plant at SSAB Oxelösund supplies the heatbase load.The conclusion in this report is that the consequences of connecting the twodistrict heating systems can be both positive and negative, depending onsystem boundaries and on the environmental focus.

The purpose of this master thesis is to implement and validate a Power System Stabilizer (PSS) to a generator at Trängslet hydropower station in Dalarna, Sweden. Problems with local rotor oscillations can occur at the hydropower station when power is transferred on a new power line (130 kV) from Northern to Southern part of Dalarna. To ensure good operation properties on this power line Fortum Generation AB and Fortum Distribution AB wants to activate a PSS on a generator.There have been investigations in which situations and what equipment that contributes to rotor oscillations. When this is known the PSS is tuned to damp these oscillations by choosing a good set of parameters. The most important parameters for good performance are to choose amount of gain and phase compensation.

This thesis is a feasibility study for a future product development project. The purpose ofthis project is to evaluate the possibilities and difficulties associated with the design of anelectric power assist servo for all terrain vehicles (ATVs). The project has been carriedout in collaboration with Nira Control AB. Nira designs and manufactures electric andelectro mechanic products mainly for the motor sport market segment.Nira Control AB is developing a fuel injection system for a new line of large ATVs oncommission. To be able to compete with manufacturers like Yamaha and Honda thecommissioner should be able to offer optional power assist steering.

In Stockholm there are currently five women, out of a total of 102 employees, working in public sports arenas. In sports arenas men are numerically superior amongst the workers as well as the visitors. These arenas are in many ways male dominated, masculinized environments. In this essay I investigate the reasons behind the uneven distribution, in terms of gender, among sports arena workers. I do this by interviewing seven female sports arena workers (the five current and two former), and by observing their workplaces.

Uppsalahem AB is a municipally owned real estate concern that owns and administrates housing for nearly 30 000 people. The company puts a lot of effort into reducing the energy use of their housing stock. This project is a master?s thesis in the energy systems programme at Uppsala University, carried out in collaboration with Uppsalahem. The aim of this thesis is to provide energy saving measures for fourteen student housing buildings in Uppsala, Sweden.

The aim of this report is to analyse the use of the capacity at the CNC (computer numerical control) cutters and show how the level of set up time for these cutters at Stålöv AB. This assignment is concrete whereas there are no subjective questions to this matter and there are only cold figures presented.Production economy is getting more important as the competition hardens and there are several different ways to increase productivity and efficiency in a company. In order to increase productivity and efficiency work studies are used to, through an analysis, find developments in methods that result in improved work methods and to establish the time that are used. Increased production of different parts and customer driven production in combination with increased demands on rationalisation of capital have led to an enlarged interest for shorter set up times in the production.To point out the use of capacity and the set up time of the cutters at Stålöv AB we used frequency studies. Frequency studies are work measure methods based on random observations on predetermined events to calculate the relative occurrence of these events.

Microproduction, also called distributed generation, is something that has become more and more popular in the electric grid. Microproduction can however lead to unacceptable performance if several units are installed in the same low voltage network. It is therefore good to know a limit where the performance of the low voltage network becomes unacceptable based on given parameters. This limit is usually called hosting capacity.In this report the hosting capacity with respect to voltage and current have been studied in three low voltage networks which are located in Falu Elnäts concession area. This has been done by simulations in a GIS-program where critical times of the grid have been simulated.

A reforming trend is captured showing that countries are shifting from defined benefit pension systems towards defined contribution systems. The reforms have been justified through predictions that the defined benefit systems will not manage to provide good enough pensions to members in the future. The newer defined contribution pension plans often include individual financial accounts where individuals have the possibility to choose how a part of their pension savings should be invested. Sweden was early to introduce such a system, which at the moment provides more than 800 funds to choose from. The aim of this thesis is to capture the market risk associated with these individual investments and does so by using Monte Carlo simulations for six selected pension funds.

The trend in the transport sector is moving towards eco-friendly, fast and convenient transportation,this results in higher demands on railway transports. To meet the demand and quality requirements,the Swedish railway network will have to expand. The cheapest way is to expand little by little butwhat impact do these small steps actually have on the capacity?This thesis examines the interactions of different improvement for the capacity on a single-trackrailway. Through simulations in the software tool RailSys this report studies what effect block signals,extra meeting stations and rebuilding existing two track passing loops to three track loops have onthe capacity.