Sök:

Sökresultat:

3915 Uppsatser om SARA-model - Sida 13 av 261

Gestaltningsförslag till ny förskola på Zakrisdal

Due to increasing regulations regarding new diesel vehicles particulate matteremissions the new Scania truck, Scania Euro 6, has been equipped with a particulatefilter. This component effectively stores the particles in the exhaust gas but must becleaned in order to prevent itself from clogging. The filter is cleaned through aprocess named regeneration which is a thermodynamic process in which thetemperature of the filter is raised through fuel supplied to the exhaust gas.The purpose of this thesis is to contribute to the development of improved controlstrategies of the temperature during the regeneration process through thedevelopment of model-based controllers. These controllers are designed in order tohave good performance in stationary as well as automatic regeneration.In order to develop these model-based controllers a model of the system isconstructed. The model is described as a linear thermodynamic grey-box model withflow varying parameters, showing good results in validation.The model provides a simulation environment during the controller design, which isfocused around the development of linear regulators with the exhaust gas mass flowas a scheduling variable whose size determines controllers? mode of operation.

Klimatsimulering av ett kontorsrum : Hur de termiska stigkrafterna påverkar ventilationseffektiviteten

AbstractIn urban societies people spend more and more time indoors, which put great demands on the indoor environment. If the ventilation is to manage the removal of unwanted substances in the indoor air, a good mixing of the air is required. The question arises that, whether the buoyancy forces will counteract a good mixing of the indoor air or not?This report aims to clear up the difficulties whether you need to consider the buoyancy forces or not, when adjusting a ventilation unit. For studying the indoor mixing of the air a two dimensional model is constructed in COMSOL Multiphysics.

Modell och analysverktyg för beräkningav frekvensförlopp

The power system modelled in this thesis work has been developed for simulationwhen e.g. the production in some part of the power system is changed. The powersystem has been modelled according to the swing mass of the system, the frequencydependency of the load and the turbine governor. The model determines the systemfrequency, the period of regulation and the power exchange between the differentsubsystems in the Nordic synchronized system.In this model the system frequency is assumed to be the same in all different parts ofthe power system and the voltage conditions in the power system are neglected. Forthat reason power swings does not occur between different subsystems in the powersystem, which usually occur as a result of the swinging connection between thetransmissions line.

Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt

A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of nitrate. Water with a too high content of nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.This thesis was performed in order to find the source of the nitrate.

Den litterära nätsajten Vulkan.se och en ny modell för den litterära processen

The aim of this thesis is to investigate how the literary site Vulkan.se affects the conditions for publishing, distribution, incorporation in value systems and feedback in the literary process, as it appears in Lars Furuland?s model of this process. The purpose is also to propose an updated version of the model. This is achieved through a qualitative testing of Furuland?s theory.

Processbarhetsteorin i undervisning : ???Analys av två program som används av andraspråksinlärare

I have with this thesis sought to understand how chick lit could be useful in the classroom in the teaching of Swedish B-course in high school. Based on the model of critical literacy I am arguing that this genre would help to meet the objectives of the policy documents which, among other things, are to critically examine and analyze various types of texts.I have found that some of these texts could be used for analyzing and critically examine the ideological dimensions of texts and cultural heritage by the model of critical literacy, and also as a counterweight to the more traditional teaching of the canonical literature as a literary historical stuff that students should learn. I have also wanted to create a basis for discussions about literature in the classroom based on the chick lit genre. To do this I have, based on three themes and questions from the model of critical literacy, tried to focus on issues that might emerge from the ideological analysis and critical review. The model aims to deconstruct norms of society, and in the work of chick lit, I wanted to show how you could deconstruct norms around gender..

Estimering av kapitalkostnad för onoterade företag

The cost of capital for traded companies is basically assessed on information from thefinancial market. Small and non-traded companies are lack of this necessary financialmarket information in order to determine an appropriate equity risk premium and tocompute the cost of capital.In the absence of financial information necessary for an external investor, it is difficult toevaluate a non-traded company with the Capital Asset Pricing model (CAPM), which isbased on the financial market information. It measures only the systematic risk, which isthe contribution of one share to the market risk of a portfolio. It is therefore important tofind models that reflect the small and non-traded companies? real business value and theirunique characteristics.

New Business Model for District Heating Firms Stabilizing the National Energy System with a Future Variable Electricity Production

The aim of this thesis is to develop a new business model for district heating and cooling firms which can contribute to a stabilization of the Swedish national energy system. The business model is developed for a district heating and cooling firm and is exemplified with Fortum Heat. The theoretical investigation around the topic creates a rigid base for following qualitative empirical studies. Osterwalder?s canvas for business model generation is used together with a Casual Loop Diagram to identify a number of business opportunities which stabilizes the national energy system.

FEM?modeller för expansionsanalys av piplines

REINERTSEN AS performs expansion and buckling analyses of pipelines using ANSYS, afinite element modelling and analysis tool. In an expansion analysis the pipeline is modelledwith thin?walled pipe elements called PIPE20 which allows plastic deformation. However, ina recent analysis the results retrieved from the PIPE20 element were incorrect for strainsabout 1 percent. One main issue was that the PIPE20 element overestimated the strains.The purpose with this Master Thesis was to become familiar with the theories and analysismethods used in pipeline design.

BIM i planeringsarbetet : Effective planning by using BIM

AbstractThe importance of good construction planning affects the final costs of the production and the timing of the project. Planning for building projects has been studied with the aim of identifying how three week planning appears in the construction industry today.A case study has been conducted in Navisworks Simulate to assess whether the software is suitable to connect the task schedule with the BIM model to create a 4D model. 4D models are used for performing 4D construction simulation to visualize the project. In order to use the benefits of the model, investment in equipment and software is required. This means higher costs for the companies.

Utveckling av en HBV/PULS-model med sammanfogade markfuktighets- och responsrutiner

Soil properties affect the chemical composition of soil water. When studying transport of chemical substances through a basin, it is therefore important to know from which soil layer the main part of the runoff is generated. The aim of this study is to develop an HBV/PULSE model with merged soil moisture and response routines, which generates good approximations of groundwater levels. It should be possible to extend the model to simulate transport of substances and take into account which soil layer the groundwater level is currently in. The hydrological version of HBV/PULSE is used since there is no need to account for pH or alcalinity at this stage.

Hållbar Ö ? en analys av möjligheterna att försörja ett modellösamhälle i Stilla Havet med solel

The goal of this paper is to provide a model for a sustainable electricity system to an island, in the Pacific Ocean near the equator.The method which has been used is to model supply and demand of electricity in the computer program Stella, through the creation of a dynamic system that balances them against each other. The result from the model will then be used to calculate the electricity price per kWh for the island.The result of the work is that electricity from solar energy is comparable with electricity produced from oil, if the oil pays for all its external costs, and the potential for pumped hydro storage plants is located. It also requires that consumers of electricity can be their own producers to avoid the expenditure of tax and reducing the cost of distribution. But since oil is a finite resource and has had a rising cost in recent years, while solar energy has had a declining cost, perhaps this will be a more competitive solution in the future.

Översvämningsrisker längs Funboån

Flooding events are no longer rare, floods occur all over the world. Accordingly, it is vital for the society and different authorities to work with flood mapping. To meet the goal of Uppsala kommun to map the risks of floods in Uppsala län, a map of the different areas around Funboån which are inside the area of risk for flooding have been developed.In the work, cross sections and the water flow have been measured. Moreover, an echo-sounding have been carried out in Funboån to map the bottom topography. From the bottom map and laser scanned data covering the study area, a terrain model was created.

Kvantitativ studie om knappsatsdesign och knappstorlekars påverkan på träffsäkerhet

A mobile testing application using Unity was developed to analyse what impact button sizes and button layouts has on the accuracy of touch as well as the time to finish a labyrinth. This was tested on a Nexus 4 phone. 28 users navigated a small object through a labyrinth in which they collect keys to open the door to the exit. Each participant did the test 6 times with different combinations of button size and button layout each time, done in a random order. Hits, misses, completion time, order of button size and order of button layout was collected and then visualized using R.

Alternativ till fortsatt elektrisk generering i Olidan

In this thesis a possible cost effective runner change of some of the units in the hydroelectric power station Olidan is investigated. The possibility to drive a unit at the same efficiency point through a change of the turbine shaft speed and the rate of discharge is tested. Furthermore the theories behind model testing, determination of efficiency increase from model to prototype and efficiency measurements shall be discussed and analyzed with Olidan as a starting point.A predicted curve has been built on information from model tests and field measurements on the existing runners and runner data from the test of the new model. The predicted curve shows the difference in efficiency between an existing runner and a modern one. It is the difference in efficiency that is used in the calculations that are to show whether changing to a pair of new runners will be cost effective or not.

<- Föregående sida 13 Nästa sida ->