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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.
171

Verslo sistemų modelio analizė, panaudojant agregatinę schemą ir loginį programavimą / Analysis of business systems REA model using aggregate schema and logic programming

Janušauskaitė, Živilė 06 June 2006 (has links)
This work presents business process analysis methodology which consists of presentation of the business processes created on the ground of the Resource Event Agent model by means of Piece–Linear Aggregate approach. The aggregate specification is analyzing using first order predicate logic while checking correctness by resolution method using logic programming based language Prolog. The work is concluded with concrete example of analysis of Resource Event Agent model based business process using the aggregate approach. The novelty of this work PLA (Piece-Linear Aggregate) model and the software tools, created on the ground of PLA (Piece-Linear Aggregate), are used the first time for business processes analysis that is defined using REA formalism. The use of such integrated models allows performing the automated analysis of general and individual properties (completeness, deadlock freeness, termination or cyclic behavior, boundedness) of defined business processes. The main results are achieved: • The methodology, that consists of presentation of the business processes created on the ground of the Resource Event Agent model by means of Piece–Linear Aggregate approach. • Verification and validation of general and individual properties by using PLA and PROLOG language approach designed system that executes the analysis of aggregate specification. • Implementing internal accounting controls as constraints in relational algebra, SQL and PROLOG language. • Concrete... [to full text]
172

Επαγωγικός λογικός προγραμματισμός : μια διδακτική προσέγγιση

Καραμουτζογιάννη, Ζωή 31 May 2012 (has links)
Ο Επαγωγικός Λογικός Προγραμματισμός (Inductive Logic Programming ή, σε συντομογραφία ILP) είναι ο ερευνητικός τομέας της Τεχνητής Νοημοσύνης (Artificial Intelligence) που δραστηριοποιείται στη τομή των γνωστικών περιοχών της Μάθησης Μηχανής (Machine Learning) και του Λογικού Προγραμματισμού (Logic Programming).Ο όρος επαγωγικός εκφράζει την ιδέα του συλλογισμού από το επί μέρους στο γενικό. Μέσω της επαγωγικής μάθησης μηχανής ο Επαγωγικός Λογικός Προγραμματισμός επιτυγχάνει το στόχο του που είναι η δημιουργία εργαλείων και η ανάπτυξη τεχνικών για την εξαγωγή υποθέσεων από παρατηρήσεις (παραδείγματα) και η σύνθεση-απόκτηση νέας γνώσης από εμπειρικές παρατηρήσεις. Σε αντίθεση με της περισσότερες άλλες προσεγγίσεις της επαγωγικής μάθησης ο Επαγωγικός Λογικός Προγραμματισμός ενδιαφέρεται για της ιδιότητες του συμπερασμού με κανόνες για την σύγκλιση αλγορίθμων και για την υπολογιστική πολυπλοκότητα των διαδικασιών. Ο Επαγωγικός Λογικός Προγραμματισμός ασχολείται με την ανάπτυξη τεχνικών και εργαλείων για την σχεσιακή ανάλυση δεδομένων. Εφαρμόζεται απευθείας σε δεδομένα πολλαπλών συσχετισμών για την ανακάλυψη προτύπων. Τα πρότυπα που ανακαλύπτονται από τα συστήματα στον Επαγωγικό Λογικό Προγραμματισμό προκύπτουν από κάποιο γνωστό θεωρητικό υπόβαθρο και θετικά και αρνητικά παραδείγματα και εκφράζονται ως λογικά προγράμματα. Ο Επαγωγικός Λογικός Προγραμματισμός έχει χρησιμοποιηθεί εκτεταμένα σε προβλήματα που αφορούν τη μοριακή βιολογία, την βιοχημεία και την χημεία. Ο Επαγωγικός Λογικός Προγραμματισμός διαφοροποιείται από τις άλλες μορφές Μάθησης Μηχανής, αφ’ ενός μεν λόγω της χρήσης μιας εκφραστικής γλώσσας αναπαράστασης και αφ’ ετέρου από τη δυνατότητά του να χρησιμοποιεί τη γνώση υποβάθρου. Έχουν αναπτυχθεί διάφορες μηχανισμούς υλοποίησης του ILP, εκ των οποίων η πιο πρόσφατη είναι η Progol, που βασίζεται σε ένα διερμηνέα της Prolog ο οποίος συνοδεύεται από έναν αλγόριθμο Αντίστροφης Συνεπαγωγής (Inverse Entailment). Η Progol κατασκευάζει νέες προτάσεις με τη γενίκευση των παραδειγμάτων που περιέχονται στη βάση δεδομένων που της δίνεται. Η θεωρία του Επαγωγικού Λογικού Προγραμματισμού εγγυάται ότι η Progol θα διεξάγει μια αποδεκτή αναζήτηση στο διάστημα των γενικεύσεων, βρίσκοντας το ελάχιστο σύνολο προτάσεων, από το οποίο όλα τα παραδείγματα μπορούν να προκύψουν. Σε αυτή την εργασία θα αναπτυχθούν αναλυτικά η θεωρία και οι κανόνες του Επαγωγικού Λογικού Προγραμματισμού, τα είδη των προβλημάτων που επιλύονται μέσω του Επαγωγικού Λογικού Προγραμματισμού, οι μέθοδοι που ακολουθούνται καθώς και ο τρόπος με τον οποίο αναπτύσσονται οι εφαρμογές του Επαγωγικού Λογικού Προγραμματισμού. Θα δοθούν επίσης παραδείγματα κατάλληλα για την κατανόηση των γνώσεων αυτών από ένα ακροατήριο που διαθέτει βασικές γνώσεις Λογικής και Λογικού Προγραμματισμού. / Inductive Logic Programming is a research area of Artificial Intelligence that operates in the intersection of cognitive areas of Machine Learning and Logic Programming. Through inductive machine learning, Inductive Logic Programming‟s objective is creating tools and developing techniques to extract new knowledge composing a background one and empirical observations (examples). Some methods are employed, the best known of which is the reverse implication, the reverse resolution and the inverse implication. Based on Inductive Logic Programming, some systems have been developed for knowledge production. The most widely used system is Progol, which uses an input of examples and background knowledge, whichε is stated in a kind of grammar compatible to that the programming language Prolog, and generates procedures in the same language that illustrate these examples. Other systems are FOIL, MOBAL, GOLEM and LINUS. There is also Cigol which is a programming language based on the theory of Inductive Logic Programming. These systems are used in many applications. The most important is the area of pharmacology, such as predictive toxicology, the provision of rheumatic disease and the design of drugs for Alzheimer's. Applications can also be found in programming, linguistics and games like chess.
173

Génération automatique de test pour les contrôleurs logiques programmables synchrones / Automated test generation for logical programmable synchronous controllers

Tka, Mouna 02 June 2016 (has links)
Ce travail de thèse, effectué dans la cadre du projet FUI Minalogic Bluesky, porte sur le test fonctionnel automatisé d'une classe particulière de contrôleurs logiques programmables (em4) produite par InnoVista Sensors. Ce sont des systèmes synchrones qui sont programmés au moyen d'un environnement de développement intégré (IDE). Les personnes qui utilisent et programment ces contrôleurs ne sont pas nécessairement des programmeurs experts. Le développement des applications logicielles doit être par conséquent simple et intuitif. Cela devrait également être le cas pour les tests. Même si les applications définies par ces utilisateurs ne sont pas nécessairement très critiques, il est important de les tester d'une manière adéquate et efficace. Un simulateur inclu dans l'IDE permet aux programmeurs de tester leurs programmes d'une façon qui reste à ce jour informelle et interactive en entrant manuellement des données de test. En se basant sur des recherches précédentes dans le domaine du test des programmes synchrones, nous proposons un nouveau langage de spécification de test, appelé SPTL (Synchronous Programs Testing Language) qui rend possible d'exprimer simplement des scénarios de test qui peuvent être exécutées à la volée pour générer automatiquement des séquences d'entrée de test. Il permet aussi de décrire l'environnement où évolue le système pour mettre des conditions sur les entrées afin d'arriver à des données de test réalistes et de limiter celles qui sont inutiles. SPTL facilite cette tâche de test en introduisant des notions comme les profils d'utilisation, les groupes et les catégories. Nous avons conçu et développé un prototype, nommé "Testium", qui traduit un programme SPTL en un ensemble de contraintes exploitées par un solveur Prolog qui choisit aléatoirement les entrées de test. La génération de données de test s'appuie ainsi sur des techniques de programmation logique par contraintes. Pour l'évaluer, nous avons expérimenté cette méthode sur des exemples d'applications EM4 typiques et réels. Bien que SPTL ait été évalué sur em4, son utilisation peut être envisagée pour la validation d'autres types de contrôleurs ou systèmes synchrones. / This thesis work done in the context of the FUI project Minalogic Bluesky, concerns the automated functional testing of a particular class of programmable logic controllers (em4) produced by InnoVista Sensors. These are synchronous systems that are programmed by means of an integrated development environment (IDE). People who use and program these controllers are not necessarily expert programmers. The development of software applications should be as result simple and intuitive. This should also be the case for testing. Although applications defined by these users need not be very critical, it is important to test them adequately and effectively. A simulator included in the IDE allows programmers to test their programs in a way that remains informal and interactive by manually entering test data.Based on previous research in the area of synchronous test programs, we propose a new test specification language, called SPTL (Synchronous Testing Programs Language) which makes possible to simply express test scenarios that can be executed on the fly to automatically generate test input sequences. It also allows describing the environment in which the system evolves to put conditions on inputs to arrive to realistic test data and limit unnecessary ones. SPTL facilitates this testing task by introducing concepts such as user profiles, groups and categories. We have designed and developed a prototype named "Testium", which translates a SPTL program to a set of constraints used by a Prolog solver that randomly selects the test inputs. So, generating test data is based on constraint logic programming techniques.To assess this, we experimented this method on realistic and typical examples of em4 applications. Although SPTL was evaluated on EM4, its use can be envisaged for the validation of other types of synchronous controllers or systems.
174

Temporal logics

Horne, Tertia 09 1900 (has links)
We consider a number of temporal logics, some interval-based and some instant-based, and the choices that have to be made if we need to construct a computational framework for such a logic. We consider the axiomatisation of the accessibility relations of the underlying temporal structures when we are using a modal language as well as the formulation of axioms for distinguishing concepts like actions, events, processes and so on for systems using first-order languages. Finally, we briefly discuss the fields of application of temporal logics and list a number of fields that looks promising for further research. / Computer Science and Information Systems / M.Sc.(Computer Science)
175

Lógicas probabilísticas com relações de independência: representação de conhecimento e aprendizado de máquina. / Probabilistic logics with independence relationships: knowledge representation and machine learning.

José Eduardo Ochoa Luna 17 May 2011 (has links)
A combinação de lógica e probabilidade (lógicas probabilísticas) tem sido um tópico bastante estudado nas últimas décadas. A maioria de propostas para estes formalismos pressupõem que tanto as sentenças lógicas como as probabilidades sejam especificadas por especialistas. Entretanto, a crescente disponibilidade de dados relacionais sugere o uso de técnicas de aprendizado de máquina para produzir sentenças lógicas e estimar probabilidades. Este trabalho apresenta contribuições em termos de representação de conhecimento e aprendizado. Primeiro, uma linguagem lógica probabilística de primeira ordem é proposta. Em seguida, três algoritmos de aprendizado de lógica de descrição probabilística crALC são apresentados: um algoritmo probabilístico com ênfase na indução de sentenças baseada em classificadores Noisy-OR; um algoritmo que foca na indução de inclusões probabilísticas (componente probabilístico de crALC); um algoritmo de natureza probabilística que induz sentenças lógicas ou inclusões probabilísticas. As propostas de aprendizado são avaliadas em termos de acurácia em duas tarefas: no aprendizado de lógicas de descrição e no aprendizado de terminologias probabilísticas em crALC. Adicionalmente, são discutidas aplicações destes algoritmos em processos de recuperação de informação: duas abordagens para extensão semântica de consultas na Web usando ontologias probabilísticas são discutidas. / The combination of logic and probabilities (probabilistic logics) is a topic that has been extensively explored in past decades. The majority of work in probabilistic logics assumes that both logical sentences and probabilities are specified by experts. As relational data is increasingly available, machine learning algorithms have been used to induce both logical sentences and probabilities. This work contributes in knowledge representation and learning. First, a rst-order probabilistic logic is proposed. Then, three algorithms for learning probabilistic description logic crALC are given: a probabilistic algorithm focused on learning logical sentences and based on Noisy-OR classiers; an algorithm that aims at learning probabilistic inclusions (probabilistic component of crALC) and; an algorithm that using a probabilistic setting, induces either logical sentences or probabilistic inclusions. Evaluation of these proposals has been performed in two situations: by measuring learning accuracy of both description logics and probabilistic terminologies. In addition, these learning algorithms have been applied to information retrieval processes: two approaches for semantic query extension through probabilistic ontologies are discussed.
176

CHROME: a model-driven component-based rule engine

Vitorino dos Santos Filho, Jairson 31 January 2009 (has links)
Made available in DSpace on 2014-06-12T15:51:39Z (GMT). No. of bitstreams: 2 arquivo2757_1.pdf: 5759741 bytes, checksum: 8075c58c36a6d409b242f2a7873fb02f (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Vitorino dos Santos Filho, Jairson; Pierre Louis Robin, Jacques. CHROME: a model-driven component-based rule engine. 2009. Tese (Doutorado). Programa de Pós-Graduação em Ciência da Computação, Universidade Federal de Pernambuco, Recife, 2009.
177

MODELOG : model-oriented development with executable logical object generation

de Souza Ramalho, Franklin January 2007 (has links)
Made available in DSpace on 2014-06-12T15:54:14Z (GMT). No. of bitstreams: 2 arquivo6624_1.pdf: 2520643 bytes, checksum: b69b2ba2918606ef2803cf6322485425 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / The Unified Modeling Language (UML) has far outgrown its initial purpose as a standard visual notation for constructing intuitive, high-level blueprint models of object-oriented software. A series of extension, such as OCL, XMI, ASL, MOF, UML profiles, and different proposed formal semantics, to the language and to its application scope have fedoff each other in synergy. While these extensions constitute a sound starting point to make UML the pivotal element for the Model-Driven Engineering (MDE) and Semantic Web (SW) visions, many other building blocks are still missing, including: (1) Complete formal semantics for UML and OCL; (2) UML inference engine based on such semantics to support model checking and intelligent agent reasoning with UML semantic web ontologies; (3) UML model compilers to fully automate both structural and behavioral code generation from detailed UML/OCL models. In this thesis, we present the MODELOG framework based on a single proposal to address these three issues: it consists of an automatic mapping from fully refined UML/OCL models to the object-oriented logic programs in the Flora-2, an executable and Turing-complete language with a well-defined formal semantics. We developed the MODELOG mapping as model transformations. As source for these transformations, we reused the UML2 and OCL2 metamodels provided by OMG and as target we developed a Flora metamodel. As we experimented and compared two language to implement the transformation: the dedicated transformation language ATL based on OCL, and Flora itself viewed as a model transformation language. As validating case study for MODELOG, we developed the Triangram robotic assembly puzzle. It is an example of planning tasks often executed by agents and it requires a complex class hierarchy together with complex structural and behavioral constraints. The Flora PSM of this puzzle was entirely automatically generated from its UML/OCL model by applying the MODELOG transformations. The main originality of this thesis is twofold. First, it simultaneously tackles various gaps in UML for its new extended role: formal specification language, MDE, semantic web services and agent engineering, Second, it does so without putting forward any new language but only by reusing a theoretically consolidated and efficiently implemented one. In contrast, previous proposals tend be limited to one or two such applications while often proposing new languages. The thesis makes contributions to various fields: For MDE, it shows the feasibility of completely automated full structural and behavioral executable code generation from a UML/OCL PIM, on a non-trivial, complex case study involving automated reasoning; For agile development, it reconcile that the robustness of formal methods with the early testing of fast prototyping, since MODELOG not only generates executable code, but also model checking code from UML/OCL models. For UML and OCL, it provides a fully integrated denotational formal semantics in Transaction Frame Logic on which Flora is based; For logic programming, it provides compositional metamodels of all the languages integrated in the Flora platform that clarify their relations and make them available as source or target language for a variety of MDE tasks such as model checking and fast prototyping; it also provides a way to develop logic programs using the consolidated full-life cycle object-oriented software engineering processes; For agent engineering, it shows how to get combine the complementary strengths of the object-oriented and logic paradigms, the two mostly widely reused in agent-oriented methods; For the semantic web service development, its introduced a highly automated MDE approach allowing to model them visually with UML-based industrial strengths method and CASE tools, and automatically generate their specification in the W3C standard SWSL, which is a XML-enabled variant of Flora
178

Sobre os fundamentos de programação lógica paraconsistente / On the foundations of paraconsistent logic programming

Rodrigues, Tarcísio Genaro 17 August 2018 (has links)
Orientador: Marcelo Esteban Coniglio / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-17T03:29:03Z (GMT). No. of bitstreams: 1 Rodrigues_TarcisioGenaro_M.pdf: 1141020 bytes, checksum: 59bb8a3ae7377c05cf6a8d8e6f7e45a5 (MD5) Previous issue date: 2010 / Resumo: A Programação Lógica nasce da interação entre a Lógica e os fundamentos da Ciência da Computação: teorias de primeira ordem podem ser interpretadas como programas de computador. A Programação Lógica tem sido extensamente utilizada em ramos da Inteligência Artificial tais como Representação do Conhecimento e Raciocínio de Senso Comum. Esta aproximação deu origem a uma extensa pesquisa com a intenção de definir sistemas de Programação Lógica paraconsistentes, isto é, sistemas nos quais seja possível manipular informação contraditória. Porém, todas as abordagens existentes carecem de uma fundamentação lógica claramente definida, como a encontrada na programação lógica clássica. A questão básica é saber quais são as lógicas paraconsistentes subjacentes a estas abordagens. A presente dissertação tem como objetivo estabelecer uma fundamentação lógica e conceitual clara e sólida para o desenvolvimento de sistemas bem fundados de Programação Lógica Paraconsistente. Nesse sentido, este trabalho pode ser considerado como a primeira (e bem sucedida) etapa de um ambicioso programa de pesquisa. Uma das teses principais da presente dissertação é que as Lógicas da Inconsistência Formal (LFI's), que abrangem uma enorme família de lógicas paraconsistentes, proporcionam tal base lógica. Como primeiro passo rumo à definição de uma programação lógica genuinamente paraconsistente, demonstramos nesta dissertação uma versão simplificada do Teorema de Herbrand para uma LFI de primeira ordem. Tal teorema garante a existência, em princípio, de métodos de dedução automática para as lógicas (quantificadas) em que o teorema vale. Um pré-requisito fundamental para a definição da programação lógica é justamente a existência de métodos de dedução automática. Adicionalmente, para a demonstração do Teorema de Herbrand, são formuladas aqui duas LFI's quantificadas através de sequentes, e para uma delas demonstramos o teorema da eliminação do corte. Apresentamos também, como requisito indispensável para os resultados acima mencionados, uma nova prova de correção e completude para LFI's quantificadas na qual mostramos a necessidade de exigir o Lema da Substituição para a sua semântica / Abstract: Logic Programming arises from the interaction between Logic and the Foundations of Computer Science: first-order theories can be seen as computer programs. Logic Programming have been broadly used in some branches of Artificial Intelligence such as Knowledge Representation and Commonsense Reasoning. From this, a wide research activity has been developed in order to define paraconsistent Logic Programming systems, that is, systems in which it is possible to deal with contradictory information. However, no such existing approaches has a clear logical basis. The basic question is to know what are the paraconsistent logics underlying such approaches. The present dissertation aims to establish a clear and solid conceptual and logical basis for developing well-founded systems of Paraconsistent Logic Programming. In that sense, this text can be considered as the first (and successful) stage of an ambitious research programme. One of the main thesis of the present dissertation is that the Logics of Formal Inconsistency (LFI's), which encompasses a broad family of paraconsistent logics, provide such a logical basis. As a first step towards the definition of genuine paraconsistent logic programming we shown, in this dissertation, a simplified version of the Herbrand Theorem for a first-order LFI. Such theorem guarantees the existence, in principle, of automated deduction methods for the (quantified) logics in which the theorem holds, a fundamental prerequisite for the definition of logic programming over such logics. Additionally, in order to prove the Herbrand Theorem we introduce sequent calculi for two quantified LFI's, and cut-elimination is proved for one of the systems. We also present, as an indispensable requisite for the above mentioned results, a new proof of soundness and completeness for first-order LFI's in which we show the necessity of requiring the Substitution Lemma for the respective semantics / Mestrado / Filosofia / Mestre em Filosofia
179

Problemas de comparação de genomas / Genoma comparison problems

Dias, Ulisses Martins, 1983- 02 August 2012 (has links)
Orientador: Zanoni Dias / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-20T03:52:46Z (GMT). No. of bitstreams: 1 Dias_UlissesMartins_D.pdf: 19168517 bytes, checksum: 463a6e15e1414ce37a0fe80f92de6b07 (MD5) Previous issue date: 2012 / Resumo: Esta tese aborda três aspectos da comparação entre genomas: primeiro, eventos de transposição; segundo, eventos de reversão e de reversão quase-simétrica; terceiro, estudo da distância entre genomas sem ligação com algum tipo específico de rearranjo. O estudo do primeiro aspecto, eventos de transposição, permitiu a criação de um novo algoritmo de aproximação na razão 1.375 e de modelos exatos usando programação em lógica com restrições para o problema da distância de transposição. Ambas as abordagens foram comparadas com outras semelhantes encontradas na literatura e, em ambos os casos, foi mostrado que o produto aqui apresentado é superior 'aqueles previamente conhecidos. Sob o segundo aspecto, eventos de reversões e de reversões quase-simétricas, houve avanços relacionados ao entendimento do processo de diferenciação das espécies na família Pseudomonadaceae e nos gêneros Mycobacterium, Shewanella e Xanthomonas com a criação de uma ferramenta de simulação capaz de gerar um histórico evolutivo com características semelhantes 'as observadas nos referidos grupos. Além disso, foram obtidos avanços em abordagens algorítmicas para o problema de construção de scaffolds usando um genoma de referência. De modo particular, foi obtida uma ferramenta superior 'as demais existentes na literatura para construção de scaffolds de genomas bacteriais. Ainda neste segundo aspecto, tratou-se do problema da distância de reversões quase-simétricas com a geração de um algoritmo guloso que fornece uma sequência de reversões quase-simétricas para ordenar qualquer permutação, além de algoritmos exatos para várias famílias específicas de permutações. No que diz respeito ao terceiro aspecto, foram desenvolvidas duas medidas que podem ser calculadas de forma eficiente (poucos segundos). Uma das medidas é adequada para genomas próximos e a outra é adequada para genomas distantes. Ambas foram avaliadas com genomas bacteriais reais, o que mostrou as vantagens e limitações de cada medida. Com esta tese, espera-se ter contribuído para a área de comparação de genomas em geral e, em particular, para a área de rearranjo de genomas / Abstract: In this PhD thesis, we work on three aspects of genome comparison: first, transposition events; second, inversion and almost-symmetric inversion events; third, whole-genome distance measures that are not connected to any specific kind of rearrangement event. The study of transposition events (first aspect) allowed us to create a new 1.375-approximation algorithm and some exact models using constraint logic programming. These approaches were compared to other published methods and in all cases our methods perform best. The second aspect of this thesis concerns inversion and almost-symmetric inversion events. In this regard, we developed a simulation tool for the study of symmetric inversions in bacterial genomes. Through this work we were able to contribute to the understanding of the evolutionary differentiation process in species of the following groups: the Pseudomonadaceae family, the Xanthomonas genus, the Shewanella genus, and the Mycobacterium genus. We used the knowledge acquired in building our simulation tool to establish a method that uses inversion signatures to generate draft genome sequence scaffolds using a complete genome as a reference. Apart from the practical applications of this research, we contribute to the computer science field by providing a theoretical framework for the almost-symmetric distance problem that can be improved in the future and can serve as a basis for approximation and heuristic algorithms. This framework is comprised of a greedy algorithm for any permutation, exact algorithms for specific families of permutation, and several lemmas and conjectures related to these problems. The third and last aspect of this thesis addresses the need for methods that can quickly and effectively compare large sets of genome sequences. We propose two new methods for efficiently determining whole genome sequence distance measures. One of them is aimed at comparing closely related genomes, and the other is meant to compare more distant genomes. Both measures were evaluated in order to find their limitations and their efficacy. It is our hope that thiswork represents a contribution to knowledge of the genome comparison field in general, and the genome rearrangement field, in particular / Doutorado / Ciência da Computação / Doutor em Ciência da Computação
180

Implementation av ett kunskapsbas system för rough set theory med kvantitativa mätningar / Implementation of a Rough Knowledge Base System Supporting Quantitative Measures

Andersson, Robin January 2004 (has links)
This thesis presents the implementation of a knowledge base system for rough sets [Paw92]within the logic programming framework. The combination of rough set theory with logic programming is a novel approach. The presented implementation serves as a prototype system for the ideas presented in [VDM03a, VDM03b]. The system is available at "http://www.ida.liu.se/rkbs". The presented language for describing knowledge in the rough knowledge base caters for implicit definition of rough sets by combining different regions (e.g. upper approximation, lower approximation, boundary) of other defined rough sets. The rough knowledge base system also provides methods for querying the knowledge base and methods for computing quantitative measures. We test the implemented system on a medium sized application example to illustrate the usefulness of the system and the incorporated language. We also provide performance measurements of the system.

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