Funderingar kring användningsfall? Denna uppsats belyser användningsfallsmodellering, en enkel, effektiv och vida spridd metod, dock förenad med vissa svårigheter. En fallstudie är genomförd på två företag för att illustrera hur användningsfall utformas och om det finns någon utformning som kan ge mervärde för utvecklingsprocessen. Ett mervärde vi funnit är att använda beskrivningssätt som alla förstår. Uppsatsen belyser även svårigheter relaterade till framtagningen, varför dessa uppstår och hur de kan undvikas.

Vid objektorienterad systemutveckling är det viktigt att man genomför en analys- och designfas, dels för att man inom ett utvecklingsteam lättare ska kunna visualisera hur ett system är tänkt att bli och dels för att kunna fånga och åskådliggöra kundens krav. Till sin hjälp i dessa faser har man metoder/processer och modelleringsspråk. Varje företag har i regel haft sin egen variant av ovan nämnda, men allteftersom kom kravet på en gemensam standard att bli oundvikligt. Sedan ett antal år tillbaka finns nu en standard. Trots det finns det säkert företag kvar som ännu inte antagit denna standard.

AbstractMy purpose with this study is to find out if it helps children who have diffuculties with their concentration if they get to practise their motor behaviour knowledge during their day at the school to promote their learning capacity. My purpose is also to find out how schools works with motor behaviour training. To get answers to my questions have I done interviews with four educationalists and I have also used books and internet sites. Motor behaviour is of importance to how children learn things in the school, without a well working motor children gets difficulties to sit still and to concentrate. The children may put their energy at the wrong things in the classroom, when the energy instead should be need to learning things.

In this essay, we have compared a conventional house to a passive house. The housesshared the same local conditions; they have the same living area and the same layout. Thedifferences between the houses were the different construction solutions for the roof, theouter walls, the floor and the heating system. Both the houses qualify the standards fromBBR and the passive house also lives up to FEBY?s special conditions.The purpose with the essay was to examine if it really is profitable to build small hoses aspassive houses.

Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.

District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

The most predominant method for forest harvesting in Sweden is the cut-to-length method based on two-machines, a harvester that fells trees and cut them in a predefined length, and a forwarder which transports logs to a landing area for further transport to a processing facility. New machine solutions have to be much gentler to the ground than today?s machines. To be able to develop a forestry machine that preserves the terrain requires a proper understanding of the interaction between tire and soil.The goal of the project is to contribute to the existing knowledge of forest machine tire-soil interaction and to develop a tire-soil model that enables dynamic simulations of forest machines operating in rough terrain. The modeling has especially been focused on the interaction between tires and soft ground.A comparison of theoretical data of different WES-based terrain interaction models and a comparison test data from a full scale field test is presented.

ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.

 This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy.

There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes. District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption Research), which has focused on climate adaption in the Nordic countries.

AbstractBuilding Information Model/Modeling/Management (BIM) is a tool that allows for efficient working methods. BIM saves time and money while providing the potential for visualization. This method of working is based on a 3D-model, and then a fourth and fifth dimension are connected. 5D modeling means that a spreadsheet creates cost estimates based on the 3D model. This provides opportunities to carry out calculations in the early stages of the projects. Calculations are currently performed manually and do not contribute to the development that the construction industry requires.

In this project a simulator has been developed (in C++) with the purpose of illustrating how changes in environmental regulations, tax levels and other policy measures affect the composition of an energy system. The aim of the project was to investigate how energy companies? investment strategies are affected when changes in economic and environmental conditions occur. A standard scenario has been created based on current Swedish conditions, but the user can create new scenarios and set parameters freely. The user is tasked with building power plants to supply the city/region with district heating and electricity during a pre-set number of years. When the simulation is finished the result is graded in the following categories: economy, environment and quality. To evaluate the simulator three scenarios were created (?early 20th century?, ?reduced environmental control? and ?future?) in addition to the standard scenario and these were compared with each other by examining how a select group of power plants perform under the given conditions.

The Republic of Moldova, situated in eastern Europe and a former part of the Soviet Union, is now experiencing a phase of transition in both society and landscape. They have hardly any fossil depots and are currently dependent on Russian gas, with 97% of their energy needs imported. The new elected government wants to move towards the EU and this is generally seen as the way to grow and reduce poverty. Security in the energy sector is important and one tool is to increase the use of renewable energy sources. Through interviews, texts, and visits I have studied the implementation of renewable energies (RE) in Moldova through a society development perspective. The study has aimed to investigate the sociotechnical complexity of this subject and to discuss the potentials and way of dealing with the subject in the specific cultural context of Moldova.

This report will examine various solar energy technologies in order to decide if they could be applied in the Royal Seaport. The Royal Seaport is a Swedish urban district under development in Stockholm, with the goal of becoming a sustainable district. Two main techniques, solar collectors and solar cells, including sub-categories, are addressed in this report. Another sub-category, a hybrid system, will also be mentioned. The main difference between solar collectors and solar cells is the type of energy produced by the system.