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Praktiska effekter av begreppsförvirring för en databas konceptuella design : En fallstudie om databas- och begreppsmodelleringWallin, Nils, Olsson, Erik January 2010 (has links)
Company X develops a laboratory information system (LIS) called System Y. The informationsystem has a two-tier database architecture consisting of a production database and a historicaldatabase. A database constitutes the backbone of a IS, which makes the design of the databasevery important. A poorly designed database can cause major problems within an organization.The two databases in System Y are poorly modeled, particularly the historical database. Thecause of the poor modeling was unclear concepts. The unclear concepts have remained in thedatabase and in the company organization and caused a general confusion of concepts. The splitdatabase architecture itself has evolved into a bottleneck and is the cause of many problemsduring the development of System Y.Company X investigates the possibility of integrating the historical database with the productiondatabase. The goal of our thesis is to conduct a consequence analysis of such integration andwhat the effects would be on System Y, and to create a new design for the integrated database.We will also examine and describe the practical effects of confusion of concepts for a databaseconceptual design.To achieve the goal of the thesis, five different method steps have been performed: a preliminarystudy of the organization, a change analysis, a consequence analysis and an investigation of theconceptual design of the database. These method steps have helped identify changes necessaryfor the organization, a new design proposal for an integrated database, the impact of theproposed design and a number of effects of confusion for the database.
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Ontology as Conceptual Schema when Modelling Historical Maps for Database StorageSvedjemo, Gustaf January 2007 (has links)
<p>Sweden has an enormous treasure in its vast number of large-scale historical maps from a period of 400 years made for different purposes, that we call map series. The maps are also very time and regional dependent with respect to their concepts. A large scanning project by Lantmäteriverket will make most of these maps available as raster images. In many disciplines in the humanities and social sciences, like history, human geography and archaeology, historical maps are of great importance as a source of information. They are used frequently in different studies for a variety of problems. A full and systematic analyse of this material from a database perspective has so far not been conducted. During the last decade or two, it has been more and more common to use data from historical maps in GIS-analysis. In this thesis a novel approach to model these maps is tested. The method is based on the modelling of each map series as its own ontology, thus focusing on the unique concepts of each map series. The scope of this work is a map series covering the province of Gotland produced during the period 1693-1705. These maps have extensive text descriptions concerned with different aspects of the mapped features. Via a code marking system they are attached to the maps. In this thesis a semantic analysis and an ontology over all the concepts found in the maps and text descriptions are presented. In our project we model the maps as close to the original structure as possible with a very data oriented view. Furthermore; we demonstrate how this ontology can be used as a conceptual schema for a logical E/R database schema. The Ontology is described in terms of the Protégé meta-model and the E/R schema in UML. The mapping between the two is a set of elementary rules, which are easy for a human to comprehend, but hard to automate. The E/R schema is implemented in a demonstration system. Examples of some different applications which are feasibly to perform by the system are presented. These examples go beyond the traditional use of historical maps in GIS today</p>
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Ontology as Conceptual Schema when Modelling Historical Maps for Database StorageSvedjemo, Gustaf January 2007 (has links)
Sweden has an enormous treasure in its vast number of large-scale historical maps from a period of 400 years made for different purposes, that we call map series. The maps are also very time and regional dependent with respect to their concepts. A large scanning project by Lantmäteriverket will make most of these maps available as raster images. In many disciplines in the humanities and social sciences, like history, human geography and archaeology, historical maps are of great importance as a source of information. They are used frequently in different studies for a variety of problems. A full and systematic analyse of this material from a database perspective has so far not been conducted. During the last decade or two, it has been more and more common to use data from historical maps in GIS-analysis. In this thesis a novel approach to model these maps is tested. The method is based on the modelling of each map series as its own ontology, thus focusing on the unique concepts of each map series. The scope of this work is a map series covering the province of Gotland produced during the period 1693-1705. These maps have extensive text descriptions concerned with different aspects of the mapped features. Via a code marking system they are attached to the maps. In this thesis a semantic analysis and an ontology over all the concepts found in the maps and text descriptions are presented. In our project we model the maps as close to the original structure as possible with a very data oriented view. Furthermore; we demonstrate how this ontology can be used as a conceptual schema for a logical E/R database schema. The Ontology is described in terms of the Protégé meta-model and the E/R schema in UML. The mapping between the two is a set of elementary rules, which are easy for a human to comprehend, but hard to automate. The E/R schema is implemented in a demonstration system. Examples of some different applications which are feasibly to perform by the system are presented. These examples go beyond the traditional use of historical maps in GIS today
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