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Event Models : An Evaluation FrameworkEgilsson, Guðlaugur Stefán January 1999 (has links)
<p>Event based programming is an important metaphor used in a variety of applications. Research and practice in this field comes primarily from two distinct sources, component software and databases. In both those fields, the need for asynchronous notifications has led to the specification and implementation of event models, but with somewhat different emphasis.</p><p>This dissertation defines an evaluation framework for evaluating event models. In doing so, it defines several factors that are important when reviewing different event models with respect to implementing applications or components that require event notification mechanisms.</p><p>It has been suggested that the event models defined for COM and CORBA can each be used as the basis for implementing advanced event services. The framework presented in this dissertation is used to evaluate these two event models with respect to their capability to support an advanced event service originating from active database research.</p>
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A Comparison of Simple Recurrent and Sequential Cascaded Networks for Formal Language RecognitionJacobsson, Henrik January 1999 (has links)
<p>Two classes of recurrent neural network models are compared in this report, simple recurrent networks (SRNs) and sequential cascaded networks (SCNs) which are first- and second-order networks respectively. The comparison is aimed at describing and analysing the behaviour of the networks such that the differences between them become clear. A theoretical analysis, using techniques from dynamic systems theory (DST), shows that the second-order network has more possibilities in terms of dynamical behaviours than the first-order network. It also revealed that the second order network could interpret its context with an input-dependent function in the output nodes. The experiments were based on training with backpropagation (BP) and an evolutionary algorithm (EA) on the AnBn-grammar which requires the ability to count. This analysis revealed some differences between the two training-regimes tested and also between the performance of the two types of networks. The EA was found to be far more reliable than BP in this domain. Another important finding from the experiments was that although the SCN had more possibilities than the SRN in how it could solve the problem, these were not exploited in the domain tested in this project</p>
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Combination of results from gene-finding programsHammar, Cecilia January 1999 (has links)
<p>Gene-finding programs available over the Internet today are shown to be nothing more than guides to possible coding regions in the DNA. The programs often do incorrect predictions. The idea of combining a number of different gene-finding programs arised a couple of years ago. Murakami and Takagi (1998) published one of the first attempts to combine results from gene-finding programs built on different techniques (e.g. artificial neural networks and hidden Markov models). The simple combinations methods used by Murakami and Takagi (1998) indicated that the prediction accuracy could be improved by a combination of programs.</p><p>In this project artificial neural networks are used to combine the results of the three well-known gene-finding programs GRAILII, FEXH, and GENSCAN. The results show a considerable increase in prediction accuracy compared to the best performing single program GENSCAN</p>
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Prediction of Protein Mutations Using Artificial Neural NetworksLundin, Johan January 1999 (has links)
<p>This thesis is concerned with the prediction of protein mutations using artificial neural networks. From the biological perspective it is of interest to investigate weather it is possible to find rules of mutation between evolutionary adjacent (or closely related) proteins. Techniques from computer science are used in order to see if it is possible to predict protein mutations i.e. using artificial neural networks. The computer science perspective of this work would be to try optimizing the results from the neural networks. However, the focus of this thesis is primarily on the biological perspective and the performance of the computer science methods are secondary objective i.e. the primary interest is to show the existence of rules for protein mutations.</p><p>The method used in this thesis consists two neural networks. One network is used to predict the actual protein mutations and the other network is used to make a compressed representation of each amino acid. By using a compression network it is possible to make the prediction network much smaller (each amino acid is represented by 3 nodes instead of 22 nodes). The compression network is an auto associative network and the prediction network is a standard feed-forward network. The prediction network predicts a block of amino acids at a time and for comparison a sliding window technique has also been tested.</p><p>It is my belief that the results in this thesis indicate that there exists rules for protein mutations. However, the tests done in this thesis is only performed on a small portion of all proteins. Some protein families tested show really good results while other families are not as good. I believe that extended work using optimized neural networks would improve the predictions further.</p>
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Integrating Ethical Considerations in Computerized Information SystemsLarsson, Göran January 1999 (has links)
<p>This work concerns ethics applied to computer technology, emphasizing the use of this technology within organizations. Computer technology has created the possibility to do things not possible before, for good and bad. Ethical reasoning can be used as a tool to provide guidance, in order to create Computerized Information Systems (CIS) that are sustainable with respect to the ethical demands that can be put upon them.</p><p>If one wants to integrate ethical considerations into a CIS, it is reasonable that ethical issues should be taken account of in systems development. As a general methodology for developing a CIS, the Systems Development Life Cycle (SDLC) will be examined. The SDLC is the place and moment when it is possible to integrate ethical considerations into a CIS.</p><p>This work will focus on, and try to explain, what characteristics are necessary in order to be able to apply ethical considerations to a methodology. This is done by examining five methodologies adopting the SDLC. It will also be examined how the three major ethical theories utilitarianism, deontologism and rights ethics will affect the SDLC, and thus eventually a CIS being implemented.</p><p>The outcome of this work are that there are limited possibilities of integrating ethical considerations into methodologies adopting a hard system approach, compared to those adopting a soft one. The ethical standards of a CIS must be established early on in the SDLC. Integration of ethical issues requires a system approach to be applied in the SDLC. Participation becomes an important feature of systems development in order to adopt ethical reasoning. The different ethical theories will put different emphasis on the group or the individual in systems development.</p>
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Infology : a study to identify possible elements of infology in some system development methodologiesZetterlund, Marie January 1999 (has links)
<p>The purpose of this work is to identify possible elements of infology in some systems development methodologies. To reach the aim two objectives were identified: to gain an understanding of the concept of infology and secondly to study different kinds of methodologies and analyse them to find out possible elements of infology. In order to reach the aim of this work a literature study was performed. Four methodologies were chosen for the analysis and the selection represented a wide range of different methodologies. They were: Soft Systems Methodology (SSM), Effective Technical and Human Implementation of Computer based Systems (ETHICS), Structured Systems Analysis and Design Method (SSADM) and Yourdon Systems Method (YSM). The infological approach has been characterised and the fundamental characteristic of infology is the distinction between data and information. A consequence from this distinction is that the users of the intended information system should participate in the developing process in order to understand the complex and dynamic relations in an organisation and information system. The results of this work have shown that the soft methodologies (SSM and ETHICS) have a high degree of infology and the more hard methodologies (SSADM and YSM) have a low degree of infology.</p>
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Hur kan XML underlätta e-handel?Axelsson, Peter January 2000 (has links)
<p>Detta examensarbete har inriktats mot XML och dess användning på Internet. Frågeställningen lyder: "Kan underhållet av presenterad information på WWW förbättras eller förenklas med hjälp av XML för ett e-handelsföretag?" Det som förväntades av detta arbete är att se om XML kan ersätta HTML och underlätta för personalen vid uppdateringar av e-handelsplatsen. Bakgrunden till arbetet är att underhållet av en webbhandelsplats i dagens läge kräver mycket manuellt arbete och kostar mycket pengar. Går det att minska det manuella arbetet kan pengar sparas. Till grund för arbetet ligger en litteraturstudie.</p><p>Kortfattat var resultatet följande:</p><p>·Kraven på serverprestanda kan sänkas m.h.a. XML.</p><p>·Tiden som läggs på uppdateringar av innehåll och utseende av webbplatser kan minskas.</p><p>·Kopplingen mellan befintligt affärssystem och webbhandelplats kan förenklas.</p><p>·Svaret på problemformuleringen är ja. XML ger ovan nämnda förbättringar och detta motiverar till att byta från ett HTML-baserat system till ett XML-baserat.</p>
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Vilka funktionskrav ställs på MPS-system för plastindustrin?Birgersson, Sebastian January 2000 (has links)
<p>Vilka funktionskrav ställs på MPS-system för plastindustrin? Vad är det för faktorer som medför att existerande standardiserade MPS-system inte kan användas inom processindustrin? Det är dessa frågeställningar ligger till grund för denna rapport.</p><p>Rapporten inleds med en genomgång av hur kravspecifikationer bör utformas, vad material- och produktionsstyrning innebär samt en introduktion till process- och plastindustrin. I de fallstudier som presenteras diskuteras processen från order till leverans med avseende på material- och produktionsstyrning.</p><p>De funktionskrav, som identifieras som viktigast för ett MPS-system för plast-industrin, kan innefattas i följande punkter:</p><p>· Prognoshantering som kan omvandla försäljningsprognos till leveransplan.</p><p>· Verktygshantering som klarar en koppling mellan produkt och verktyg.</p><p>· Materialbehovsberäkning som kan hantera ingöt kontra produkt.</p><p>· Spårning vid felsökning.</p>
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Arbetsgivarnas policy beträffande anställdas datoranvändning under arbetstidCarlsson, Anders January 2000 (has links)
<p>I detta arbete undersöker jag frågan om hur arbetsgivarnas policy för de anställdas datoranvändning under arbetstid ser ut. Jag har gjort en jämförelse mellan kommuner och verkstadsföretag inom Västra Götaland.</p><p>Rapporten inleds med en introduktion till privata angelägenheter, personlig integritet och kontroll av de anställda. Vidare behandlas hur en policy ser ut, behovet av en policy och hur det ser ut hos arbetsgivarna gällande policys för datoranvändningen. I denna del tas bland annat tidigare undersökningar och publikationer upp.</p><p>För att kunna besvara denna fråga har jag använt mig av enkätundersökning. 11 kommuner och 11 verkstadsföretag ingår i undersökningen. Dessutom har jag gjort fyra intervjuer, två hos kommuner och två hos verkstadsföretag.</p><p>Resultatet visar att 45% av verksamheterna har en policy för de anställdas datoranvändning under arbetstid, samt att det är något vanligare med policys där antalet Internetanvändare är stort.</p>
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Användarmedverkan vid systemutveckling : en jämförande metodstudieFranzén, Ann-Charlotte January 2000 (has links)
<p>Ordet användarmedverkan används ofta inom systemutvecklingsområdet, men vad som egentligen menas med användarmedverkan är enligt min uppfattning otydligt. Många metoder specificerar att användarna skall involveras på olika sätt men det slutliga engagemanget sker ändå utifrån vad organisationen och det aktuella projektet avser att lösa. Denna rapport skall belysa två systemutvecklingsmetoder från olika länder och hur de ställer sig till användarmedverkan. Rapporten genomförs i huvudsak som en litteraturstudie.</p>
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