The purpose of the study was to investigate the use and losses of energy in an existing older building. Another purpose was also to look through various options for heating systems with renewable energy in the building. The aim was to reduce the use and losses of energy. The first step was to study the related electricity bills of the building and also perform measurements and calculations of the building envelope and ventilation. The next step was to find out the possible actions for energy saving by performing measurements and calculations.

Stockholm is growing with almost two fully loaded SL-buses a day. One of the consequences that derive from this is the increase of public transport travelers who put the regionally governed public transport up to the test in terms of its capacity. The Transport administration in Stockholm County initiated 2015 a project with the purpose of simplifying the calculation of bus stop capacities. A hypothesis (set up by the Transport administration) based on that a model for calculation of bus stop capacities could be calibrated for Stockholm conditions is being researched in this bachelor?s essay.The study is implemented by self-collected traffic data from bus stops located in the Stockholm city center.

This thesis, drawing from several empirical investigations, reaches the conclusion that there seems to be a positive correlation between the level of democracy and the level of state capacity in Latin American countries. This correlation is explained by a hypothesis derived from Rational Choice theory. With some important caveats, this conclusion is then applied to the discussion about democracy as a form of government. Within democracy, the thesis also offers an insight into different electoral systems and its possible implications, mostly on a theoretical level. The thesis only exists in swedish as of yet..

Self-driving cars are soon to become a reality to the commercial market. A self-driving car does not have a human operator, which enables some interesting characteristics. The main benefits are considered to be:The number of accidents and traffic jams should be reduced.Enhanced comfort.Energy usage could be decreased while capacity could be increased.This study concerns the causes for improved energy efficiency. The reason for improved energy efficiency is mainly because of the variation in terms of acceleration, braking and distance holding are reduced. The vehicles are more intelligent and can work together as a unity.

Abstract   This degree project comprises 30 credits, i.e. 20 weeks of work. The work mainly deals with the energy balance for a multi-family house in Västerås and the requirements for energy conservation in the Swedish building code, BBR. Calculations of the energy balance are supplemented by a number of interviews. Energy conservation in general has become more important in recent years and the subject is in line with increased public awareness. This importance and attention is explained by environmental problems in general and global warming in particular, but also by rising energy prices.

A growing interest for the climate and the environment has led to an increased interest forenvironmentally friendly and renewable energy sources, such as biogas. Planning new biogasplants requires a decision basis including facts about approximate amounts of biogas possibleto produce at the plant. The purpose of this thesis is to develop a model that calculates theapproximate biogas and digestate production from a planned or existing biogas plant.Developing the model required a literature review and studies of calculations concerningbiogas and digestate production performed by WSP Sweden AB. As a complement to themodel development, facts about substrates for biogas production were compiled through aliterature review. In addition the methane potential from selected materials was determined bybatch experiments.

The market for biofuels from the forests have had a positive development and the job initiators for this master´s thesis wanted to examine the profitability of a method for harvesting forest fuel, which was unfamiliar to them. The method was the ?long tree tops-method?, here called the LT-method. The LT-method is characterised by the fact that timber is harvested as the only roundwood assortment while the rest of the stem, which in other cases would become pulpwood, is harvested as forest fuel together with the logging residues. The method is based on the assumption that advantages in handling of the forest fuel assortment such as increased load weights for forest hauling and truck transportation, should compensate for the lower price for pulpwood when sold as forest fuel. The aim of the study was to compare the profitability of the LT-method with the GROT-method (harvest of timber, pulpwood and logging residues) and conventional logging without any harvest of forest fuel, and aslo to try to identify factors affecting the profitability of the different methods.

By conducting interviews, studies as well as scanning the current scientific landscape, this paper examines the opportunities of increasing current capacity within the public transportation system in Stockholm with simple financial means for the benefit of the travelers. The paper focuses on the central station of the subway system and how adjustments of processes carried out in relation to the turnstiles could increase performance within areas of interest, given the preferences of the travelers. The theoretical framework of the paper includes models from the field of capacity management as well as theories related to the pedestrian behavior. Applying these theories and models to the collected data, the paper derives some main conclusions. First of, people using the public transportations system, and especially the subway, consider speed and dependability as the most important performance objectives for the caretakers of the public transportation system, SL and MTR to master.

This master thesis was initiated with the aim to answer at what level of installed capacity of wind power in the northern parts of Sweden it would be beneficial to improve the transmission capacity from the northern Sweden. During the process of this work the aim has changed to try and create a model that can be used to analyze how well the hydro power installed in the northern Sweden can even out the quick changes in wind power production.To create a good model of all hydro power in northern Sweden is a very large job, unfortunately too large for a master thesis. This report therefore ends with an extensive analysis of the simplifications that have been made and their effects as well as a list of the future work that has to be done.The model that has been created have shown to be effective and produce good results. The conclusions that can be made is that the northern Swedish hydro power have very good possibilities to balance the wind power production. Only a few cases where water have been spilled even though there has been some free capacity has been discovered.

Individual cellulose ?bers were studied to identify the transport and absorbtion phenomena as well as the in?uence of drying. A Chalmers University of Technologydeveloped method within ESEM (Enviromental Scanning Electron Microscope) has been used in this study. The results from the laborations gave the following conclu-sions: The transport of water occurs in ?bers in the ?ber wall surface and the lumen.

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

The acid deposition of sulphur- and nitrogenoxides from combustion of coal and oil cause acidification that lowers pH and gives increased contents of metals and altered aquatic biodiversity in the stream. The liming of lakes and streams, which was introduced to resist the acidification, demand large economic resourses despite of the decreased deposition of the acidifyng substances. Some of the streams are influenced by the acid deposition, while others are naturally acidic. It is therefore importaint to separate the anthropogenically acidified waters from the naturally acidic, in order to optimize the use of governmental fundings for liming. This thesis aims to estimate the acidity status and impact of acidification on 24 catchments upstream liming dispensers, which is part of the liming activities at the County of Dalarna.The acidity status of the streams was classified according to the Swedish Environmental Protection Agency old classification system (Naturvårdsverket 1999) as very acid to acid, with small ability to withstand a pH-change (alkalinity) due to acid deposition.

The purpose with this work was to investigate some alternatives for an effective handling with grain, to find the most economic alternative. It is not common that moisture content is below 14% when harvesting grain in Sweden. To store the grain safe it has to be preserved in some way. I have described some of the most common systems for preserving grain in this paper. I have used the systems as a basis when I made calculations in handling the grain for a company. I have chosen a company placed in south of Sweden. The productions are crop farming and pork.

Most companies have a bottleneck in their production, that is a constraining re-source. When the demand is higher than the capacity in the constraining resource it is impossible to produce the demanded output. This problem leads to delayed deliveries, unhappy customers and ultimately to decreased revenue. Bottlenecks therefore has a significant role in production and must be handled thereof.MW Power in Sävsjö, Sweden designs and manufactures water and steam boilers for the customer's unique needs. MW Power invested in a new plasma cutting ma-chine but the machine has not reached the expected capacity.

The purpose of this thesis has been to build a parameterized model of a prototype motor in the program Solidworks, to use in future optimization of aspects of effectiveness and weight. The result were two models. The first model were one minor part of the whole design in 2D, to be able to optimize and study the minor part with a faster loss simulation. The second model was the whole design in 3D. The whole model were done with the three programs Solidworks, Comsol and Matlab.