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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Verification of completeness and consistency in knowledge-based systems : A design theory

Fogelqvist, Petter January 2011 (has links)
Verification of knowledge-bases is a critical step to ensure the quality of a knowledge-based system. The success of these systems depends heavily on how qualitative the knowledge is. Manual verification is however cumbersome and error prone, especially for large knowledge-bases. This thesis provides a design theory, based upon the suggested framework by Gregor and Jones (2007). The theory proposes a general design of automated verification tools, which have the abilities of verifying heuristic knowledge in rule-based systems utilizing certainty factors. Included is a verification of completeness and consistency technique customized to this class of knowledge-based systems. The design theory is instantiated in a real-world verification tool development project at Uppsala University. Considerable attention is given to the design and implementation of this artifact – uncovering issues and considerations involved in the development process. For the knowledge management practitioner, this thesis offers guidance and recommendations for automated verification tool development projects. For the IS research community, the thesis contributes with extensions of existing design theory, and reveals some of the complexity involved with verification of a specific rule-based system utilizing certainty factors.
162

建立本體式財務會計資訊系統 / Construct an Ontology-based Financial Accounting Information System

黃炳榮 Unknown Date (has links)
財務會計資訊系統是企業基礎且必要的資訊系統,提供內、外部使用者有關企業的經營績效資訊,作為內部經營者的管理依據及外部投資者的決策參考。然而由於法令頻繁的變更及企業本身策略需求的改變,會計資訊系統面臨很高的更新、維護成本。   本研究提出一個以本體為基礎的資訊系統架構,首先修改W.E. McCarthy於1982年提出的REA 模型,利用本體工程方法建立財務會計本體,描述企業流程及會計處理知識;再利用規則式系統之技術,於財務會計本體外建立系統存取規則及介面,呈現系統樣貌與功能。於法令變更及需求改變時直接修改本體內容,彈性變更系統內的流程、運作規則,達成減少維護成本、增加彈性之目標。 / Accounting Information System(AIS) is a kind of important system in an enterprise. That provides financial information for users to make decisions. However, accounting principle and manage strategy changing frequently that cause highly maintenance cost.   This research proposes an ontology-based system structure. First, we amend the REA model and analyze business processes and accounting rules to build an accounting ontology by ontology engineering. Then, we use the rule-based system skill to develop the system interface. Whenever accounting principle be modified, we update the ontology only. This design promotes the flexibility and decreases the cost.
163

Using Event-Based and Rule-Based Paradigms to Develop Context-Aware Reactive Applications.

Le, Truong Giang 30 September 2013 (has links) (PDF)
Context-aware pervasive computing has attracted a significant research interest from both academy and industry worldwide. It covers a broad range of applications that support many manufacturing and daily life activities. For instance, industrial robots detect the changes of the working environment in the factory to adapt their operations to the requirements. Automotive control systems may observe other vehicles, detect obstacles, and monitor the essence level or the air quality in order to warn the drivers in case of emergency. Another example is power-aware embedded systems that need to work based on current power/energy availability since power consumption is an important issue. Those kinds of systems can also be considered as smart applications. In practice, successful implementation and deployment of context-aware systems depend on the mechanism to recognize and react to variabilities happening in the environment. In other words, we need a well-defined and efficient adaptation approach so that the systems' behavior can be dynamically customized at runtime. Moreover, concurrency should be exploited to improve the performance and responsiveness of the systems. All those requirements, along with the need for safety, dependability, and reliability pose a big challenge for developers.In this thesis, we propose a novel programming language called INI, which supports both event-based and rule-based programming paradigms and is suitable for building concurrent and context-aware reactive applications. In our language, both events and rules can be defined explicitly, in a stand-alone way or in combination. Events in INI run in parallel (synchronously or asynchronously) in order to handle multiple tasks concurrently and may trigger the actions defined in rules. Besides, events can interact with the execution environment to adjust their behavior if necessary and respond to unpredictable changes. We apply INI in both academic and industrial case studies, namely an object tracking program running on the humanoid robot Nao and a M2M gateway. This demonstrates the soundness of our approach as well as INI's capabilities for constructing context-aware systems. Additionally, since context-aware programs are wide applicable and more complex than regular ones, this poses a higher demand for quality assurance with those kinds of applications. Therefore, we formalize several aspects of INI, including its type system and operational semantics. Furthermore, we develop a tool called INICheck, which can convert a significant subset of INI to Promela, the input modeling language of the model checker SPIN. Hence, SPIN can be applied to verify properties or constraints that need to be satisfied by INI programs. Our tool allows the programmers to have insurance on their code and its behavior.
164

Tratamento de imprecisão na geração de árvores de decisão

Lopes, Mariana Vieira Ribeiro 03 March 2016 (has links)
Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-08T20:30:11Z No. of bitstreams: 1 DissMVRL.pdf: 2179441 bytes, checksum: 3c4089c4b24a3d98521f8561c6f2c515 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-08T20:30:33Z (GMT) No. of bitstreams: 1 DissMVRL.pdf: 2179441 bytes, checksum: 3c4089c4b24a3d98521f8561c6f2c515 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-08T20:30:39Z (GMT) No. of bitstreams: 1 DissMVRL.pdf: 2179441 bytes, checksum: 3c4089c4b24a3d98521f8561c6f2c515 (MD5) / Made available in DSpace on 2017-08-08T20:31:24Z (GMT). No. of bitstreams: 1 DissMVRL.pdf: 2179441 bytes, checksum: 3c4089c4b24a3d98521f8561c6f2c515 (MD5) Previous issue date: 2016-03-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Inductive Decision Trees (DT) are mechanisms based on the symbolic paradigm of machine learning which main characteristics are easy interpretability and low computational cost. Though they are widely used, the DTs can represent problems with just discrete or continuous variables. However, for some problems, the variables are not well represented in this way. In order to improve DTs, the Fuzzy Decision Trees (FDT) were developed, adding the ability to deal with fuzzy variables to the Inductive Decision Trees, making them capable to deal with imprecise knowledge. In this text, it is presented a new algorithm for fuzzy decision trees induction. Its fuzification method is applied during the induction and it is inspired by the C4.5’s partitioning method for continuous attributes. The proposed algorithm was tested with 20 datasets from UCI repository (LICHMAN, 2013). It was compared with other three algorithms that implement different solutions to classification problem: C4.5, which induces an Inductive Decision Tree, FURIA, that induces a Rule-based Fuzzy System and FuzzyDT, which induces a Fuzzy Decision Tree where the fuzification is done before tree’s induction is performed. The results are presented in Chapter 4. / As Árvores de Decisão Indutivas (AD) são um mecanismo baseado no paradigma simbólico do Aprendizado de Máquina que tem como principais características a fácil interpretabilidade e baixo custo computacional. Ainda que sejam amplamente utilizadas, as ADs são limitadas à representação de problemas cujas variáveis são do tipo discreto ou contínuo. No entanto, para alguns tipos de problemas, pode haver variáveis que não são bem representadas por estes formatos. Diante deste contexto, foram criadas as Árvores de Decisão Fuzzy (ADF), que adicionam à interpretabilidade das Árvores de Decisão Indutivas, a capacidade de lidar com variáveis fuzzy, as quais representam adequadamente conhecimentos imprecisos. Neste texto, apresentamos o trabalho desenvolvido durante o mestrado, que tem como principal resultado um novo algoritmo para indução de Árvores de Decisão Fuzzy, cujo método de fuzificação dos atributos contínuos é realizado durante a indução da árvore e foi inspirado no método de particionamento de atributos contínuos adotado pelo C4.5. Para validação do algoritmo, foram realizados testes com 20 conjuntos de dados do repositório UCI (LICHMAN, 2013) e o algoritmo foi comparado com outros três algoritmos que abordam o problema de classificação por meio de técnicas diferentes: o C4.5 que induz uma Árvore de Decisão Indutiva, o FURIA, que induz um Sistema Fuzzy Baseado em Regras, porém não segue a estrutura de árvore e o FuzzyDT que induz uma Árvore de Decisão fuzzy realizando a fuzificação dos atributos contínuos antes da indução da árvore. Os resultados dos experimentos realizados são apresentados e discutidos no Capítulo 4 deste texto.
165

Raisonnement par règles et raisonnement par cas pour la résolution des problèmes en médecine / Rule-based and case-based reasoning for medical problem solving

Steichen, Olivier 07 December 2013 (has links)
Les médecins cherchent à résoudre les problèmes de santé posés par des individus. Une solution individualisée tient compte de la singularité du patient concerné. L'individualisation des pratiques est-elle possible et souhaitable? Le cas échéant, selon quelles modalités peut-elle ou doit-elle être réalisée'? La première partie de la thèse vise à montrer: que la question se pose depuis les premières théories de la décision médicale (Hippocrate) ; qu'elle s'est posée de façon aiguë au début du XIX" siècle, avec l'apparition des études statistiques; et que l'observation médicale et son évolution concrétisent la façon dont la documentation des cas et leur individualisation interagissent. La deuxième partie reprend la question dans le contexte contemporain, à travers la naissance de l'"evidence-based medicine", ses critiques et son évolution. La troisième partie montre que l'articulation du raisonnement par règles et du raisonnement par cas modélise de façon opérationnelle une démarche raisonnée d'individualisation des décisions médicales. Ce modèle simple permet de rendre compte du mouvement d'aller-retour entre deux conceptions de l'individualisation et d'en proposer une version équilibrée, mise à l'épreuve dans les domaines de l'évaluation des pratiques et de la littérature médicale. / Physicians try to solve health problems of individual patients. Customized solutions take into account the uniqueness of the patient. Is the individualization of medical decisions possible and desirable'? If so, how can I tor should it be performed? The first part of the thesis shows: that the question arises since the first conceptualizations of medical reasoning (Hippocrates); that is was much debated in the early nineteenth century, when statistical studies were first performed to guide medical decisions; and that the medical observation and its evolution materialize how case documentation and management interact. The second part addresses the issue in the current context, from the birth of evidence-based medicine, its cri tics and its evolution. The third part shows that linking rule-based and case-based reasoning adequately pictures the process of customizing medical decisions. This simple model can account for the movement between two kinds of customization and leads to a balanced approach, tested in the field of practice evaluation and medical literature.
166

Uma solução para apoiar processos de desenvolvimento centrado na arquitetura / A solution to support development process centered in the architecture

Silva, Italo Carlo Lopes 30 December 2014 (has links)
The success of a software project is strongly related with architectural design. However, designing the right Software Architecture is a very subjective task and takes a long time, being much influenced by architect's experience and the quality of requirements engineering. This architectural knowledge, usually, is not documented, since it is considered tacit knowledge of architects or other stakeholders, and eventually dissipates. It is also essentially important to ensure the consistency between software architecture and implementation. However, this mapping is usually made manually, based only on the developer's understanding over the software architecture, which requires high discipline. Thus, errors can arise during this phase, compromising the consistency amongst architectural decisions and source code. The objective of this work is to present a tool-based solution that supports young architects by recommending a suitable architectural style, based on the system's requirements, particularly the quality attributes of the system. The tool encompasses both trade-o resolution over quality attributes and recommendation of architectural styles based on quality attributes. Finally, based on the recommended architecture, the tool will generate the system structural source-code, using a component implementation model called COSMOS*, providing traceability between architectural design and implementation. The proposed solution has been evaluated in the context of a specific domain of Learning Management System (LMS), in order to illustrate the tool support in the execution of an architectural design process. / O sucesso de um projeto de software está fortemente relacionado com o projeto arquitetural. No entanto, projetar a arquitetura de software correta é uma tarefa muito subjetiva e leva muito tempo, sendo muito influenciada pela experiência do arquiteto e a qualidade da engenharia de requisitos. Este conhecimento arquitetural, geralmente, não está documentado, uma vez que é considerado o conhecimento tácito dos arquitetos ou dos interessados, e, eventualmente, se dissipa. Também é essencialmente importante assegurar a consistência entre a arquitetura de software e a implementação. No entanto, esse mapeamento é feito manualmente na maioria das vezes, baseado apenas no entendimento do desenvolvedor sobre a arquitetura, exigindo disciplina por parte dele. Assim, erros podem surgir durante esta fase, comprometendo a consistência entre as decisões arquiteturais e o código fonte. Em face destas dificuldades, foi desenvolvido este trabalho, cujo o objetivo é apresentar uma ferramenta que apoie jovens arquitetos com a recomendação de um estilo arquitetural adequado, baseado nos requisitos do sistema, particularmente os atributos de qualidade do sistema. A ferramenta compreende tanto resolução trade-off sobre os atributos de qualidade e recomendação de estilos arquiteturais com base em atributos de qualidade. Por fim, com base na arquitetura recomendada, a ferramenta irá gerar o código estrutural do sistema, utilizando um modelo de implementação de componente chamado COSMOS*, proporcionando rastreabilidade entre projeto arquitetural e a implementação. A solução proposta foi avaliada no contexto de um domínio específico dos Ambientes Virtuais e Aprendizagem (AVA), a m de ilustrar o suporte da ferramenta na execução de um processo de projeto arquitetural.
167

Sistema Especialista para Supress?o Online de Alarmes em Processos Industriais

Souza, Danilo Curvelo de 01 February 2013 (has links)
Made available in DSpace on 2014-12-17T14:56:12Z (GMT). No. of bitstreams: 1 DaniloCS_DISSERT.pdf: 3897603 bytes, checksum: cd98fa05a1dee36b5186c50e95b2f03b (MD5) Previous issue date: 2013-02-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Operating industrial processes is becoming more complex each day, and one of the factors that contribute to this growth in complexity is the integration of new technologies and smart solutions employed in the industry, such as the decision support systems. In this regard, this dissertation aims to develop a decision support system based on an computational tool called expert system. The main goal is to turn operation more reliable and secure while maximizing the amount of relevant information to each situation by using an expert system based on rules designed for a particular area of expertise. For the modeling of such rules has been proposed a high-level environment, which allows the creation and manipulation of rules in an easier way through visual programming. Despite its wide range of possible applications, this dissertation focuses only in the context of real-time filtering of alarms during the operation, properly validated in a case study based on a real scenario occurred in an industrial plant of an oil and gas refinery / A opera??o de processos industriais vem se tornando mais complexa ao longo dos anos, e um dos elementos que possibilitam este aumento de complexidade ? a integra??o de novas tecnologias e solu??es inteligentes empregadas no setor, como ? o caso dos sistemas de apoio ? decis?o. Neste sentido, esta disserta??o visa o desenvolvimento de um sistema de aux?lio ? opera??o baseado em uma ferramenta computacional chamada de sistema especialista. O objetivo principal ? tornar a opera??o mais confi?vel e segura ao maximizar a quantidade de informa??es relevantes a cada situa??o atrav?s da utiliza??o de um sistema especialista baseado em regras pr?-moldadas para uma determinada ?rea de conhecimento. Para a modelagem de tais regras foi proposto um ambiente de alto-n?vel, que permite a cria??o e manipula??o de regras de forma facilitada atrav?s de programa??o visual. A despeito de sua ampla gama de poss?veis aplica??es, esta disserta??o tem como foco o contexto de filtragem em tempo real de alarmes durante a opera??o, devidamente validada em um estudo de caso baseado em um cen?rio real ocorrido em uma planta industrial de uma refinaria de petr?leo e g?s
168

Visualization of tabular data on mobile devices / Visualisering av tabulär data på mobila enheter

Caspár, Sophia January 2018 (has links)
This thesis evaluates various ways of displaying tabular data on mobile devices using different responsive table solutions. It also presents a tool to help web developers and designers in the process of choosing and implementing a suitable table approach. The proposed solution for this thesis is a web system called The Visualizing Wizard that allows the user to answer some questions about the intended table and then get a recommended responsive table solution generated based on the answers. The system uses a rule-based approach via Prolog to match the answers to a set of rules and provide an appropriate result. In order to determine which table solutions are more appropriate to use for which type of data a statistical analysis and user tests were performed. The statistical analysis contains an investigation to identify the most common table approaches and data types used on various websites. The result indicates that solutions such as "squish", "collapse by rows", "click" and "scroll" are most common. The most common table categories are product comparison, product offerings, sports and stock market/statistics. This information was used to implement and establish user tests to collect feedback and opinions. The data and statistics gathered from the user tests were mapped into sets of rules to answer the question of which responsive table solution is more appropriate to use for which type of data. This serves as the foundation for The Visualizing Wizard.
169

Personalizable architecture model for optimizing the access to pervasive ressources and services : Application in telemedicine / Modèle d’architecture personnalisable pour l’optimisation de l’accès à des ressources et services pervasifs : Application à la télémédecine

Nageba, Ebrahim 07 December 2011 (has links)
Le développement et l’usage croissants de systèmes pervasifs, dotés de fonctionnalités et de moyens de communication de plus en plus sophistiqués, offrent de fantastiques potentialités de services, en particulier pour l’e-Santé et la télémédecine, au bénéfice de tout citoyen, patient ou professionnel de santé. L’un des challenges sociétaux actuels est de permettre une meilleure exploitation des services disponibles pour l’ensemble des acteurs impliqués dans un domaine donné. Mais la multiplicité des services offerts, la diversité fonctionnelle des systèmes, et l’hétérogénéité des besoins nécessitent l’élaboration de modèles de connaissances de ces services, des fonctions de ces systèmes et des besoins. En outre, l’hétérogénéité des environnements informatiques distribués, la disponibilité et les capacités potentielles des diverses ressources humaines et matérielles (instrumentation, services, sources de données, etc.) requises par les différentes tâches et processus, la variété des services qui fournissent des données aux utilisateurs, et les conflits d’interopérabilité entre schémas et sources de données sont autant de problématiques que nous avons à considérer au cours de nos travaux de recherche. Notre contribution vise à optimiser la qualité de services en environnement ambiant et à réaliser une exploitation intelligente de ressources ubiquitaires. Pour cela, nous proposons un méta-modèle de connaissances des principaux concepts à prendre en compte en environnement pervasif. Ce méta-modèle est basé sur des ontologies décrivant les différentes entités précitées dans un domaine donné ainsi que leurs relations. Puis, nous l’avons formalisé en utilisant un langage standard de description des connaissances. A partir de ce modèle, nous proposons alors une nouvelle méthodologie de construction d’un framework architectural, que nous avons appelé ONOF-PAS. ONOF-PAS est basé sur des modèles ontologiques, une base de règles, un moteur d’inférence, et des composants orientés objet permettant la gestion des différentes tâches et le traitement des ressources. Il s’agit d’une architecture générique, applicable à différents domaines. ONOF-PAS a la capacité d’effectuer un raisonnement à base de règles pour gérer les différents contextes d’utilisation et aider à la prise de décision dans des environnements hétérogènes dynamiques, tout en tenant compte de la disponibilité et de la capacité des ressources humaines et matérielles requises par les diverses tâches et processus exécutés par des systèmes d’information pervasifs. Enfin, nous avons instancié ONOF-PAS dans le domaine de la télémédecine pour traiter le scénario de l’orientation des patients ou de personnes victimes de problèmes de santé en environnement hostile telles que la haute montagne ou des zones géographiquement isolées. Un prototype d’implémentation de ces scénarios, appelé T-TROIE a été développé afin de valider le framework ONOF-PAS. / The growing development and use of pervasive systems, equipped with increasingly sophisticated functionalities and communication means, offer fantastic potentialities of services, particularly in the eHealth and Telemedicine domains, for the benifit of each citizen, patient or healthcare professional. One of the current societal challenges is to enable a better exploitation of the available services for all actors involved in a given domain. Nevertheless, the multiplicity of the offered services, the systems functional variety, and the heterogeneity of the needs require the development of knowledge models of these services, systems functions, and needs. In addition, the distributed computing environments heterogeneity, the availability and potential capabilities of various human and material resources (devices, services, data sources, etc.) required by the different tasks and processes, the variety of services providing users with data, the interoperability conflicts between schemas and data sources are all issues that we have to consider in our research works. Our contribution aims to empower the intelligent exploitation of ubiquitous resources and to optimize the quality of service in ambient environment. For this, we propose a knowledge meta-model of the main concepts of a pervasive environment, such as Actor, Task, Resource, Object, Service, Location, Organization, etc. This knowledge meta-model is based on ontologies describing the different aforementioned entities from a given domain and their interrelationships. We have then formalized it by using a standard language for knowledge description. After that, we have designed an architectural framework called ONOF-PAS (ONtology Oriented Framework for Pervasive Applications and Services) mainly based on ontological models, a set of rules, an inference engine, and object oriented components for tasks management and resources processing. Being generic, extensible, and applicable in different domains, ONOF-PAS has the ability to perform rule-based reasoning to handle various contexts of use and enable decision making in dynamic and heterogeneous environments while taking into account the availability and capabilities of the human and material resources required by the multiples tasks and processes executed by pervasive systems. Finally, we have instantiated ONOF-PAS in the telemedicine domain to handle the scenario of the transfer of persons victim of health problems during their presence in hostile environments such as high mountains resorts or geographically isolated areas. A prototype implementing this scenario, called T-TROIE (Telemedicine Tasks and Resources Ontologies for Inimical Environments), has been developed to validate our approach and the proposed ONOF-PAS framework.
170

Decentralising the codification of rules in a decision support expert knowledge base

De Kock, Erika 04 March 2004 (has links)
The paradigm of Decision Support Systems (DSS) is to support decision-making, while an Expert System’s (ES) major objective is to provide expert advice in specialised situations. Knowledge-Based DSS (KB-DSS), also called Intelligent Decision Support Systems (IDSS), integrate traditional DSS with the advances of ES. A KB-DSS’ knowledge base usually contains knowledge expressed by an expert and captured by a knowledge engineer. The indirect transfer between the domain expert and the knowledge base through a knowledge engineer may lead to a long and inefficient knowledge acquisition process. This thesis compares 11 DSS packages in search of a (KB-) DSS generator where domain experts can specify and maintain a Specific Decision Support System (SDSS) to assist users in making decisions. The proposed (KB-) DSS-generator is tested with a university and study-program prototype. Since course and study plan programs change intermittently, the (KB-) DSS’ knowledge base enables domain experts to set and maintain their course and study plan rules without the assistance of a knowledge engineer. Criteria are set to govern the (KB-) DSS generator search process. Example knowledge base rules are inspected to determine if domain experts will be able to maintain a set of production rules used in a student registration advice system. By developing a prototype and inspecting knowledge base rules, it was found that domain experts would be able to maintain their knowledge in the decentralised knowledge base, on condition that the objects and attributes used in the rule base were first specified by a builder/programmer. / Dissertation (MSc Computer Science)--University of Pretoria, 2005. / Computer Science / unrestricted

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