Outages in the electric grid can be costly for society. Because of this, reliability is one of the parameters used to regulate network companies. Reliability in electrical grids can be measured with SAIDI, system average interruption duration index, which for Fortum Distribution has increased in Stockholm?s distribution network (11 kV) in the early 2000?s.By using outage data for Stockholm from 2011-2013, sets of parameters to be used for reliability calculations in the network information program Tekla NIS were derived. Two different options for investment were then analysed: changing old cables with high fault frequencies, and installing automatic switching in distribution substations.

This essay deals with development in Latin America. We have picked out some factors that the theories in development theory emphasize on. The first section of the study consists of a statistical analysis, were the main purposes are to study the relationship between the independent variables and the dependent and to choose which two countries we should focus on in the next section. The countries we decided to study were Costa Rica and Nicaragua, because these countries have shown very different levels of development. From this study we have concluded that political stability, economical investements and human investments are the most important factors when creating development..

The purpose of this thesis is to investigate the degree of influence of holes in the web of steel beams with long spanson weakening of their bearing capacity. Making holes in the web of the beam generally reduces the bearing capacity of the beam. However, it might be necessary seen from both an architectural perspective as well as from a building services perspective by creating an opportunity for building installations.The objective of this thesis is to examine how much an I-beam can be weakened without sacrificing safety and functionality. The investigation has been done by using Finite Element Method through commercial software.The regulation for structural design of building structures in Sweden used to be specified in the document known as BKR. But this was replaced by the European norm Eurocode back in May 2011.

The aim of this study is to look how the Social Service has handled custody issues. The study has a legal and social aspect with a purpose to investigate how the law affects the social administration as well as the family. During a period of one year a quantitative and qualitative study was performed within the social administration in a nearby community. The study focus is partly on the relationship between the law, family and society. The main questions have been: Which one of the parents, mother or father, did in fact get the custody and why? How has the children?s point of view been reported in the inquiry? A child needs a well organized everyday life in a preferably conflict free environment.

The third most common conifer in Sweden is Pinus contorta (lodgepole pine). It originates from the western part of North America and was brought here in the end of the 1920s. The lodgepole pine is today allowed for commercial plantations in central and northern Sweden, excluding high altitude locations. Since 1979 only plantations with scientific purpose are allowed in south-central and south Sweden. This document is focused on how lodgepole pine manage perform compared with Pinus sylvestris (Scots pine) in the southernmost part of Sweden, Götaland. The idea came from the fact that the Swedish government is evaluating a notification from the National Forest Agency that suggests lodgepole pine to be allowed for commercial plantation even in southern Sweden.

The purpose of this study has been to look how pedagogic process interacts in horse riding lessons. In order to research this problem I have used an ethnographic approach and during a week I observed ten riding lessons in two separate Riding house in the south of Sweden. In my theoretical frame I have used Michel Foucault ?Discipline and punish? as a toll to make clear how dominance and submission is present and active in the horse riding education. The conclusion shows how dominant power rules by its presence and creates submission, stability and feeling of security. The discipline is used to create a feeling that will bring the riders to new experience and develop their talent.

The purpose of this project was to further develop and complete a quadcopter that had been built in an earlier course at KTH, so that it could be used for demonstration and education at the school. The quadcopter was at the beginning of the project completed when it came to hardware, and there was some software functionality implemented but no system for automatic stabilization. The main goal of the project was to implement such a system, and to combine it with the previous functionality to make the quadcopter operable and able to fly. To create a functioning and stable ground multiple basic software features has been implemented, and on top of that additional software to improve the safety, stability and functionality. The most important part is the control system that is responsible for converting sensor and control signals to suitable motor values.

The energy that the earth receives from the sun hourly has potential to cover a year?s energy demand in the world. Further, this type of energy is environmentally friendly, natural and free of cost. This report covers solar energy in an urban environment and consists of a case study of installations of photovoltaic cells in a part of the city of Stockholm. It is mainly the economic aspects that are covered but there is also a discussion about the practical consequences and the sustainability as a result of integration of solar energy in an urban environment. The aim of the study is to present results from economic calculations for utilization of solar energy in chosen buildings in Kungsholmen in Stockholm.

This thesis deals with numerical simulation of earth pressure against tubular bridges in the software Plaxis. Plaxis is a FEM (Finite Element Method) software based on numerical calculations for which approximate solutions are developed through an iterative process. The program is specifically designed for soil and rock mechanical tests, such as voltage and deformation calculations in soil.The Royal Institute of Technology conducted in 2005, field tests on tubular bridges of corrugated steel, which was part of Ersa Bayoglu Fleners PhD (Bayoglu Flener, 2009). She studied how two different tubular bridges deformed during installation and filling. Tests and measurements were made during filling.

This Master?s Thesis aims to investigate and assess the methods used to decrease the discharge ofmetals, primarily copper, from the water purification plant at Assa Industries plating factory inEskilstuna.Literature studies of the purification methods precipitation, ion exchange, evaporation, reverseosmosis and electrolysis has been done to appraise the adequacy of the technique. Thesetechniques are commonly used for purification of industrial waste water.Assa has four plating lines: the Trumline, the big Zinkline, the new Zinkline and the Decorativeline. The new Zinkline is the most modern of the four lines and purification is done byrecirculation over an ion exchange unit. The demand for fresh water is thereby heavily reduced.The Trumline, the big Zinkline and the Decorative line all use older techniques.

It is found that the properties of the record years of 1965-1975 is leaking a lot of energy andthese properties are facing a major energy efficiency. From the energy aspect, the facade isafflicted with poor thermal insulation which is a big problem. To address this problem addinginsulation is a good alternative to reduce overall energy consumption of a building. Thewindows on these buildings are also a problem from the energy point of view. Therefore,there are many reasons considered for energy upgrading.

Nation building is vital in post-war states to bring the people that have been at war together. To restore peace in a state, many different actors need to work together to bring stability, safety, and advancement to a new nation. There are several methods of nation building, and this thesis evolves around three of them. This is a qualitative study where three theories on nation building are used to analyze the development of nation building, and the obstacles Bosnia and Herzegovina still has to reach a national identity. Several studies are used in this thesis to show how the development has evolved in Bosnia and Herzegovina.

In this diploma work the approach of determining the required amount of reinforcement in slabs exposed to pure tension is processed, on behalf of Ramböll Uppsala. It is a well-known problem in the industry that there are uncertainties in the determining of the amount of crack reinforcement, especially for structures exposed to pure tension. Cracking caused during the time of dehydration in concrete slabs is the most common defect according to statistics made by CBI[1], which provides numbers as high as 35 % of all the defects caused on slabs are generated by cracks. Comparisons between Sweden's former national standard BBK 04, Building Regulations for concrete structures due to restrained forces of shrinkage, and the current European standard Eurocode 2 are carried out through theoretical studies and concludes with several examples of calculations. Rigorous calculations of both standards, BBK 04 and Eurocode 2 with application of the national annex in Sweden and Denmark are performed.

Between 1965 and 1974, the Swedish Parliament decided to build one million dwellings, called Million Program. The million program buildings were erected with new, untried design solutions, in a short range of time, and at low cost. The residential buildings from that time are now greatly in need of renovation. The municipal housing company, Gavlega?rdarna, renovates and improves the energy efficiency at some of it?s apartment buildings in the district Sa?tra, Ga?vle.

In the fluidized bed furnace at Rönnskärsverken, Skelleftehamn, sulphur-containing ore concentrates are roasted in order to remove about 50% of the sulphur in the incoming ore concentrate. This occurs in order to reach the goal of a matte containing 55% of copper in the following smelting process. At the same time as the ore concentrate is partially roasted pollutions as arsenic, antimony and bismuth are expelled. Earlier made thermodynamic calculations of equilibrium suggested that calcium and magnesium form stable compounds with arsenic and thereby inhibit expellation of arsenic in the fluidized bed furnace, an element that is undesired. The purpose of this thesis work was to gain knowledge of the mechanisms behind the formation of these stable arsenic compounds.