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4135 Uppsatser om Database model - Sida 17 av 276

3D-modellering i AutoCAD -att skapa en digital huskonstruktion

3D-modelling in AutoCAD This thesis is done in cooperation with LB-Hus in Bromölla, and have aimed to establish a digital AutoCAD model of one of the company?s house types and to find out what opportunities there are to do visualisations in the form of images directly from the programme. Modeling has been carried out so that the very construction of the house is included. Interiors and installations, with the exception of the ventilation system, have been left out in the model. The model has been created with solid models after a comparative study made between solid models and surface models to find out which option in this case was the easiest to handle and took up the least space.

Rocchio, Ide, Okapi och BIM : En komparativ studie av fyra metoder för relevance feedback

This thesis compares four relevance feedback methods. The Rocchio and Ide dec-hi algorithms for the vector space model and the binary independence model and Okapi BM25 within the probabilistic framework. This is done in a custom-made Information Retrieval system utilizing a collection containing 131 896 LA-Times articles which is part of the TREC ad-hoc collection. The methods are compared on two grounds, using only the relevance information from the 20 highest ranked documents from an initial search and also by using all available relevance information. Although a significant effect of choice of method could be found on the first ground, post-hoc analysis could not determine any statistically significant differences between the methods where Rocchio, Ide dec-hi and Okapi BM25 performed equivalent.

Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden

The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.

Utveckling av lastmodell för Uppsala fjärrvärmenät

The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends.

Kunskapsteori och kunskapsorganisation: En diskursanalys

This Masters thesis concerns epistemology in Knowledge Organization KO, as a field of study in Library and Information Science LIS. Using a theoretical model by Birger Hjørland and foucauldian discourse analysis as springboards, this study analyses three epistemological discourses in the practice of KO. The aim of the study is to show how these discourses are constituted and demarcated in relation to KO, as well as to examine how they fit into Hjørlands model. A brief historical outline of some epistemological trends in LIS is sketched, as well as examples of how different epistemological schools influence different parts of KO, e.g. information retrieval, indexing- and classification theory.

Modellering av reserv- och nödkraftsystem i JAS 39 Gripen

Simulation is a vital tool during development of JAS 39 Gripen, since money and time can be saved.The Auxiliary and Emergency Power System, AEPS, is a subsystem of the secondary power system in Gripen. It has the function of providing the aircraft with electrical and hydraulical power before activation and after deactivation of the main engine. The system also functions as backup in case of a safety critical problem in the main power supply system. The system basically consists of a control unit and an auxiliary gearbox. The gearbox is driven by an air turbine.

Metoder för prediktion av kardiovaskulär sjukdom med njurfunktionen

This study examines if the prediction of cardiovascular disease in hypertensive patients can be improved upon when renal function and microalbuminuria are added to the classical risk factors The predictive capability of a model is measured by discrimination, calibration, reclassification and Harrell's C.The results are ambigious. In most cases, microalbuminuria should be included in the model, but the results regarding the other measures of renal function are varied. Therefore, the selection of risk factors to include in the model depends on which measure of prediction one prioritizes..

Modellbaserad systemutveckling i komplexa verksamheter. En fallstudie av Coremetoden

In system development it is today increasingly common to use a model-based system development method. These methods that are suited for Agile work with simple and quick updates and implementations of new applications in systems conform to the requirements that are becoming more important today, namely more flexible and less expensive system that still maintain high quality and safety.A company that has been working with this type of system development method for a long time is Genicore AB, which also has developed their own tools and model language in order to better model the information management systems in complex and abstract operations. Genicore AB is trying to spread their method other developers and have therefore taken the initiative to start this study. The method is evaluated and tested by two students with relatively little experience in model-based systems engineering in order to gain a new perspective on how the method functions. The method has been applied to an educational activity in order to test it in a new domain, and this led us to our research question;?What criteria are of particular relevance in the implementation of a MBSD method on on complex businesses??Through literature reviews and interviews, we formed an idea of how model-based system development works from a theoretical perspective, and then continued to the case study conducted on the educational activities at the faculty of IT at University of Gothenburg.

Ett företags internationaliseringsprocess : - i ett land kulturellt skilt från dess hemmamarknad

AbstractPurpose:The purpose of the study is to describe the internationalization process of one firm when in a country culturally diverse from the firm?s original market.Methodology/approach:The study is a single case study which examines one firm?s internationalization process when entering the Chinese market. The approach has been an empiric interaction between empirical and theoretical data.Findings:The theory of the Uppsala model was applied to the case-company to test the model?s completeness. The authors found weaknesses and added three more aspects to the model.

Kultur och kommers. En analys av Eva Unanders kommersiella lånbibliotek 1818-1829

This thesis has been written with the intention of investigating a commercial lending library to be found in Stockholm in the first decades of the nineteenth century. We chose this subject because it is a relatively unexplored area. Furthermore, we were curious to know what books could be found in the library. The lending library was run as a business thus giving a good indication of the contemporary reader's taste in literature. The lending library that we chose had a total of three thousand titles in those of its catalogues that have survived to the present day and was run by a woman called Eva Unander.

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.

Webbshop för Tyger & Ting

This report describes how we made a dynamic website combined with staticalweb pages and a web shop for the Swedish company Tyger & Ting.The employer Tyger & Ting wish to run a working web shop on their site butthey want to keep their old system of updating pages with their old applicationfrom Intellyweb1, which creates statical HTML pages.The goal of this exam paper has been to learn to create a functional web shopwith user friendly layout and appealing design and also to take orders andfulfill wishes from a real employer.The report is describing how Intellyweb?s application and its statical web pageshas been implemented on a dynamic web page. The report does also describehow this site has been build and how the problems with the coding have beensolved. The coding has been made with HTML, PHP and MySQL. CSS hasalso been used.

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.

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