This master thesis describes the development of an UPS module. UPS is an acronym for Uninterruptable Power Supply. The UPS module has been developed at the company AerotechTelub AB. The UPS module delivers the necessary voltage and current in case of a power interrupt. If a power interrupt occur, the computer system has one to three minutes available to store data and shut down correctly.

AbstractConsider a ?uid being heated from below. The heating leads to an upward convectiveforce that is counteracted by the viscous forces of the ?uid. If the convectiveforce is large enough in comparison to the viscous forces the ?uid will be put in anunstable state.

The purpose of this study was to examine if there are gender differences in computer use among the young. Our aim was to find out in what respects boys and girls differ, if at all. The main method of investigation is a literature review. We have also made a complementary empirical study in a public library. The literature studied principally covers computer use at home and in school.

This thesis of 15 hp has been implemented at Halmstad University, incollaboration with Saab Dynamics in Linköping. Saab Dynamics is a companyoperating in the defence industry where competition is tough. This necessitatesnew ways to increase efficiency in the company, which is the basis for this thesis.Saab Dynamics wants to introduce simulation driven design. Since SaabDynamics engineers have little experience of simulation, required a usermethodology with clear guidelines. Due to lack of time, they chose to assign thetask to students, which resulted in this thesis.The aim of the thesis is to develop a methodology in mechanical design, wherethe designer uses the FE analysis early in the design process to develop thestructures' mechanical properties.

This essay deals with the subject of communication through Facebook. In this survey we studied 100 youths from Karlstad and their communication habits and behavior patterns on Facebook. The social network site Facebook has since its start in 2004 made a mark in modern communication. Today in 2010 the site has more than 500 million users. This paper wants to study what happens to other types of communication.

This report treats a Master Thesis performed at Scania CV AB. The task was to create a computer model of a hydraulic actuator system in the software AVL Hydsim. The system consists of two spring-loaded masses with surrounding hydraulic components. The purpose of the model is to study phenomenon and problems in the system, as well as to be a support in the development of the system. It is not supposed to be used to study absolute values in its current form.

This master thesis consists of the creation of shock absorber models for percussive rock drills. A model of the rock was also developed. These models were connected to existing models of the rock drill to create a complete simulation of the rock drilling process.When the models had been created the rock model was evaluated by comparison with measured values from lab tests. The verified rock model was then used to evaluate the shock absorber models.Four new shock absorber concepts have been developed. Three of these have been modelled, while the fourth have only been sketched and described.The evaluation of the models showed the following:? Simulations of the single shock absorber don?t correlate to reality very well.

Om man vill skapa ett realistiskt hav inom Computer Graphics är det viktigt att man har snygga övergångar till andra material. Ett exempel på detta är stränder och det är precis där fokusen på den här studien har legat. Studien gick ut på att hitta en enklare lösning på att visuellt förbättra stränder inom Computer Graphics. För att göra detta så testade två olika metoder i olika experiment. Den ena tekniken som testades var att simulera partiklar för att få fram en bättre strandlinje och de andra var att skapa en shader för att förbättra den.

Rapporten beskriver arbetsgången vid utvecklingen av ett kompressorkit till Yamahas snöskotermodell RX-1. Arbetet innefattar konstruktion och dimensionering av tryckkammare och laddluftkylare. Datorverktyg i form av CAD (Computer Aided Design) och FEA (Finite Element Analysis) har använts till att konstruera och dimensionera ingående komponenter. Arbetet har resulterat i kompletta CAD-modeller av ett prototypkit färdigt för CAM- beredning (Computer Aided Manufacturing) och tillverkning..

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.

The aim of this thesis is to study preschool-teachers? experiences from using the computertablet as a tool for learning and teaching, in order to gain knowledge of how the integrationalprocess of information and communications technology (ICT) in preschool has progressedsince its instatement. The background that caused interest to make this study was the rapidprogression of the use of ICT-tools in childrens? everyday lives and the troubles that havesurrounded the process of integrating these tools into preschool-practices. The theoreticalbasis for the analysis of the research lies within the socio-cultural perspective.

The purpose of this study was to examine what students themselves think about using computers in school. The study was conducted in a school in central Sweden. The students in focus were students with reading and writing difficulties, dyslexia or language difficulties such as an other native language. A total of eight students were interviewed. The interviews were analyzed using thematic analysis.

This paper is the result of a case study conducted at Uppåkra Mekaniska AB during the spring of 2006. The task that was presented by Uppåkra was to develop a basis for a decision for the planning activities at the company, so that in the future they can create lot-sizes which are based upon a total cost perspective. Total cost in regards to lot-sizing is defined as the sum of the administrative reordering costs and warehousing cost per stock keeping unit.To collect data a series of interviews and observations were conducted. This data was then used during the lot-sizing simulation and analysis. The 15 units that the simulation was conducted on were grouped into three item classes depending how many different machine setups they required during the production process.

The purpose of this thesis is to investigate if there are environments that use some kind of central authentication system within institutions/schools. The hypothesis is that an institution not using a form of central authentication service has more need for maintenance and as such is considered a higher cost for the organization. The gathering of data has been done through interviews with technical personal at Blekinge Tekniska Högskola and Linköpings Universitet. Based on the technical background of the authors, and the system limited to discussing Windows and UNIX operating systems, a discussion and analysis of the systems working today has been done, with emphasize on the hypothesis..

In this study I have compared two different development methods of reading and writing. I have done this by interviewing five first grade teachers in elementary schools and it is based on qualitative research interviews. The aim of the study was to immerse myself in which methods these five teachers describe that they have used. They got to describe how they work and how they have tought the students to read and write. I have investigated if the teachers think that the computer is a good tool. The investigation also shows if the teachers believe that the students´ writing skills deteriorate if they can use the keyboard instead. I came to the conclusion that four of the teachers used Arne Trageton´s method (2005) which means that the students learn how to write by using to computer.