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20234 Uppsatser om Reduced form model - Sida 2 av 1349

Modellbygge av mekaniksystem och riktmotorer i stridsvagn 122

This master thesis is one part of a project, called ?StabSim?, with the purpose to develop a simulation model for the align and stabilisation system in main battle tank 122. The origin of this project is that it should be possible to make control analysis without risking any hardware. Besides that it will be easy to change components in order to investigate the behaviour of the system. The report includes modelling of tower and weapon mechanics and also the modelling of the synchronous motors, which control these.

Modellering, identifiering och reglering av skannern i ett laserbatymetrisystem

The purpose with this masters thesis was to model the scanner in a system for laser bathymetry. The model was then used to develop a controller for the scanner so a good search pattern was achieved. Two different types of models have been tested, a physical model and a Black Box model of Box Jenkins type. The physical model has been derived from Lagranges equations. Identification experiments have been used to compute the Black Box model and to find the unknown parameters in the physical model.

Livscykelanalys av flerbostadshus ? energieffektiviseringsåtgärder för minskade koldioxidutsläpp

The importance of energy- and environmental issues has increased, and the work towards reducing carbon dioxide emissions plays a major part. The European Union has set up goals for the membership countries to work towards this to happen. The carbon dioxide emissions in Sweden have been reduced the last few years, but there is still a lot to do. About 30 per cent of Sweden?s carbon dioxide emissions generate from energy usage related to housing, this is why the housing sector is of interest to examine.

Vanvårdens inverkan på nötkreaturs välfärd och hälsa

Farmers are required to make sure that cattles basic needs are met, but still every year cases of neglect occur where the farmer has not complied within the animal welfare law and regulations. The aim of this study was to investigate how cattle are affected physically and behaviourally by neglect in the form of underfeeding, starvation and lack of sanitation, which animals are most vulnerable to the impact and what prospects they have to recover. The study was conducted as a literature study and the results show that these types of neglect have a large impact on the cattle welfare. Underfeeding and starvation causes physical changes leading to reduced milk production, reduced muscle mass, impaired immune function, poor reproductive performance and changes in rumen microflora leading to decreased number of microbes and pH change. Physical changes due to the lack of sanitation consist of increased vulnerability to hoof diseases and mastitis, burns, and increased sensitivity to temperature.

Modellering av indunstning på Södra Cell Mönsterås

Evaporation is a part of the chemical recovery department at wood pulping mills. The purpose of evaporation is to remove water from the black liquor, which makes the liquor combustible. The process is very energy demanding, and having a well-functioning model of the system is of greatest interest. The model can then be used to study energy consumption and to test different control strategies. Two models have been developed during the master thesis.

Studie samt reglering av luft- och massflöde för en barkpanna

This report treats two assignments that concerns the biofuel furnace at Billerud Skärblacka AB and how these assignments were solved. The assignments were: reducing the number of CO-spikes and tuning the overfire air control loop. To reduce the number of CO-spikes the possibility that skewness in mass distribution affects the number of CO-spikes were study. The skewnwss of mass distribution was controled and adjusted with two experiments. The conclusion that was made is that the skewness of mass distribution were not sufficient enough to affect the number of CO-spikes.

Price adjustment and vacancies on theStockholm market ? Estimation of rent levelsdue to office-allocations

The Stockholm office market segment have for a long time been considered a safe havenwhen it comes to withstand negative turmoil in the form of rental compression due toeconomic fluctuation, especially in the CBD demographic. Recently however, a large numberof banks and institutions, amounting to some 200000 square meters, have decided to relocateto more peripheral locations with the aim of cost reductions on rent. This mass exodus isstudied with focus on rental dynamics as the result of increased vacancies. Other variables arestock changes and employment. The method is econometric combined with an interviewseries.

Avfall på byggarbetsplatsen : statistik som hjälper platschefen

The purpose of this report is to find a model of statistics for construction and demolition waste, which makes it useful for the local manager at the building site. The intention with the model is that it will be used as a support of the local manager, to direct his project towards reduced strain of the environment. The model will also be used to make it easier to control that the claims from authority and aims for the environment are achieved. To familiarise with the subject waste handling within the building and construction sectorI have done a literature search. I have also been studying rules and regulations regarding the waste handling.

Mellan två kulturer: Fem forskare i arkeologi om inställning till vetenskaplig tidskriftspublicering

The main aim in this thesis is to analyse the attitudes of fivearchaeologists at the Department of History, University ofGothenburg, on the subject of scholarly publishing injournals. The investigation has been led by a set of questionsconcerning the motives and conditions for submitting articlesto scholarly journals.The primary way of collecting emprical data is based onsemistructured qualitative interviews. To get a broaderpicture, the publishing patterns of the archaeologists at theDepartment of History were mapped using the databaseGöteborgs universitets publikationer (GUP). A documentstudy was also conducted.The analysis uses Björk & Holmström?s The net value ofsubmission model to highlight which factors are assumed toinfluence an author when submitting to a scientific journal.This model is reduced and developed to six aspects whichmore or less effect the decision making of the author whenpublishing an article in a scientific journal.

Demonstrationsprojektets roll i framväxten av ny teknik: Fallstudier av två vindkraftprojekt

This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.

Modellering av en panna med rörlig rost :  

The aim of this master thesis was to create a dynamic model for the processes in a solid fuel boiler of the moving grate type. Another aim with the model was to keep it as simple as possible but still able to catch the dynamics of the processes in the bedplate of the boiler. The creation of the model had its origin from drying and combustion equations used in earlier modeling work of boilers. The represented model has been used to simulate different kinds of disturbances in a boiler and different ways to control the boiler. These tests show that controlling a number of parameters in the bed of the boiler is an effective way to keep the grate stable during disturbances.

Modellering och reglering av drivenheter i gaffeltruck

To enable the enhancement of the driver's environment in a forklift, an alternative form of steering has been evaluated. An earlier concept with a combined driving and steering wheel has been exchanged to a concept with two driving wheels. A link wheel has replaced the combined driving and steering wheel. The steering is done through differentiation of the velocities of the two driving wheels. The scope of this master thesis is to create a simulation model, create a control program and to evaluate the concept of two driving wheels.

Adaptiv katalysatormodell för reglering

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.

Diversifiering i lantbruksföretag : en litteraturstudie om hur utvecklingsprocessen ser ut i lantbruksbaserade företag som utvecklar nya verksamhetsgrenar

Today´s debate in farming is being focused on tourism, outdoor life and hobbies in the rural areas. This is of interest also for the general public as a way of counteracting the depopulation of the rural areas. Within the last years, the farming has become more technically advanced and hence efficient. This has led to increased production volumes and wider selection of products with lower margins for the farmer as a consequence. When the profitability is reduced, the farmer is faced with the choice of either increasing efficiency or diversification of the business.

Modell av en synkronmaskin för PSCAD/EMTDC med magnetisk mättning i d-led och elektriskt gränssnitt för fältmatare

This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.

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