This master?s thesis describes the development of a model of the catalystsystem aiming at control by an MPC. A well functioning model, which is suitable in control purpose, is important while emission legislation become more and more hard to fulfill for the car manufacturers. Much research has been done in the field of physical modeling of the system, but in this work a linear adaptive time discrete ARX-model is developed and validated.The systems tendency to change its dynamic during usage implies that the model must be adaptive. The developed model proved to be well functioning and shows promising conditions for the MPC design.

This study's main objective was to identify adolescents participation in alternative sport activities and which kind of physical activity that was preferred by adolescents who didn't had any earlier experience of sport clubs. The study combined interviews and surveys with the purpose to get both adolescents and sport leaders perspective. A total of five interviews were performed and fifty-four surveys was collected. The results showed that adolescents already physical active were those who participated in alternative sport activities. Who participate in alternative sport activities can depend on habitus, comprehended capital forms and in which social field the sport activities exists..

The purpose of this report is to illustrate potentials and problems with withdrawal of quality timber of birch. The purpose is also to describe possible ways to increase available quantities of quality timber. Former research is reviewed as introduction. The study begins with a prognosis of future volumes of birch timber based on consequence analyze by Swedish Forestry Agency. To illustrate the importance of active maintenance, two stands are estimated and simulated in the Heureka module StandWise.

The textbook is one of the instruments that teachers and students have available in their teaching. For many years has textbook regarded as being too controlling and as a barrier to students development in mathematics. Textbooks primary mission is to promote learning. My study aims to provide an overview of how effective teachers use the textbook in mathematics education as well as the pros and cons they see with their work. The work includes interviews with five active mathematics teachers.

Examensarbetet gick ut på att konstruera ett robotlås. Ett robotlås håller fast roboten i sitt transport/utskjutningsrör till det är dags för roboten att avfyras. Det första som gjordes var att förutsättningslöst försöka komma på så många grundidéer som möjligt. Efter detta togs de krav vi hade fått med. Dessa bestod av mått- krafts- tids- och miljökrav.

This study's main objective was to identify adolescents participation in alternative sport activities and which kind of physical activity that was preferred by adolescents who didn't had any earlier experience of sport clubs. The study combined interviews and surveys with the purpose to get both adolescents and sport leaders perspective. A total of five interviews were performed and fifty-four surveys was collected. The results showed that adolescents already physical active were those who participated in alternative sport activities. Who participate in alternative sport activities can depend on habitus, comprehended capital forms and in which social field the sport activities exists..

AimTo validate the STOPP-8-questionnaire (S8Q), containing items from the SIH-questionnaire, against the criterion method accelerometry to estimate its capacity to assess 8 year old Swedish children?s physical activity (PA). Can it assess children?s physical activity? Can it differentiate the active children from the sedentary? If the answer is yes, how well can it do so? MethodData was collected during fall and winter the school year of 2008 - 2009 via the project STOPP-8. Out of 676 children at 12 schools in Stockholm area, 155 (boys n=72, girls n=83) provided complete questionnaire data and wore an accelerometer (Actiwatch 4) during 7 consecutive days which provided data for mean and median activity, time spent sedentary, in moderate to vigorous PA and vigorous PA.

The Swedish Transport Administration manage nearly 4,000 railway bridges in different condition and age around the country. These bridges is in constant need of maintenance and requires continuous inspections. This thesis is designed as a damage investigation on a single-track railway bridge south of Solvarbo in Säter municipality. The railway bridge is in operation and serves over 10,000 trains a year, everything from speed trains to freight trains. The bridge is built as a beam bridge, simply supported over a road.

Due to the decrease in obtaining driver?s licenses among young people, the main purpose of this study was to acquire a deeper understanding of young people?s attitudes towards driver?s license and towards driver?s education. This is a qualitative study with a theoretical approach, which combines Bourdieu with post modern theories. By using focus groups a wide rage of attitudes among young people have been gathered. Having a driver?s license is still considered a standard among young people even though their attitude mostly depends on their need for one.

Purpose: The aim of this thesis has been to study and obtain greater understanding of the consequences of active social media use. Specifically, in terms of social identity, social life and the sense of belonging. Secondly, the thesis studies the consequences of disconnecting and for a limited amount of time opt out of the social media context.Method/material:  The study is based on an explorative, cultural ethnographically-inspired method, in which four respondents were studied: two men and two women, all frequent users of social media. This was done in three steps: initial interviews, followed by social media diaries and finally a focus group. By allowing these methods to complement each other, the goal was to create an overall picture of the importance of social media in their everyday lives.The study's focus lies on the week in which the respondents kept social media diaries.

My own experiences as an upper secondary school teacher and the increase in research on masculinity in educational settings that occurred during the late 1990 emphasizing on the gender gap in achievement and grades is the point of departure for this thesis. The aim is to investigate how boys in upper secondary school are constituted and constitute themselves as motivated and achieving learning subjects. Another aim is to see what possibilities there are to form different teaching practices to create other possible positions for me and the pupils. The research questions are 1) How does boys´ construction of masculinity constitute how they see their own ability to be motivated and achieve in school 2) What significance do my shifting approaches and expectations on the pupils as well as teaching have on the boys constitution as learning subjects? To answer these questions I use a theoretical framework of feminist poststructuralist.

Detta examensarbete behandlar slamhanteringen på Sibbhults avloppsreningsverk (Sarv).I denna rapport tas det upp hur avvattningen och förtjockningen av slammet går till i dagsläget och vilka förändringar som kan göras för att förbättra dessa processer.Här visas även vilka eventuella vinster som kan fås med förändringar och eventuella investeringar i en avvattningsapplikation. Redan med små medel kan förtjockningen av slammet förändras, även om det inte införskaffas en mekanisk avvattnare, som t ex med inblandning av polymerer i avloppsvattnet.För att finna olika fungerande alternativ har information insamlats från flera företag som tillhandahåller applikationer för slamavvattnare. Information har även införskaffats genom egen erfarenhet under min verksamhetsförlagda utbildnings (VFU) period på SArv, och vid diskussion med personal som arbetar vid vatten- och avloppsreningsverken i Östra Göinge kommun..

Due to their complexity and heavy wear from rail traffic, switches are a sensitive part of the railway infrastructure and moreover expensive to maintain. Furthermore, increasing railway traffic not only accelerates the wear rate but also obstructs the necessary maintenance measures. This paper examines the opportunities for a transition to a long-term maintenance strategy in the Swedish railway network. It contains a study of the maintenance strategy of Banverket, and also analyses statistics of errors in the railway infrastructure. The survey was completed utilising interviews with infrastructure managers, maintenance contractors, planners of railway operations and the Banverket material service department.

5 till 7 miljoner ton asfalt har tillverkats och lagts ut under de senaste åren i Sverige och anläggningsbranschens årliga omsättning ligger på ca 4 mljarder kronor per år. Samtidigt har asfaltmarknadsbranschens upphandlingsmetoder varit ett diskutabelt ämne runt om i världen.Examensarbetet består av en geografisk prisjämförelse av asfalt och studera de ingående faktorer som påverkar priset. Intervjuer har gjorts med beläggningsentreprenörer från olika företag i Mellan- till Sydsverige. Resultatet påverkas av att reliabiliteten är låg eftersom relativt få aktörer har svarat på frågeformuläret, men visar på kraftiga prisskillnader mellan olika regioner. Totalkostnaden för beläggning, emulsion, bergmaterial, transport, maskin och hantverk skilde nästan 50 % mellan den med lägst och den med högst pris.

This essay discusses the problems with the high rate of long-term sickness leave among women in Sweden. It is based on interviews with six women suffering from stress-related illness. The results show that these women hardly ever recieved an explicit diagnosis and therefore did not feel that their illness was acknowledged. In the abscense of measurable symptoms they were sometimes stigmatisized and accused of simulating their problems. From this position they tried to legitimize their situation by presenting themselves as respectable women.