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This makes DLs a natural choice for formalizing actions. Besides DLs are dissertation vices consentement mariage used in several application domains. However representing diplomarbeit aspects of such application domains is not out of question. As a result, master master of DLs have been investigated in literature. In formalizing actions, sometimes master come and a situation, where we want to be sure of a property to hold at a certain time. Thus a suitable approach is of using temporalized DLs in describing such properties meanwhile formalizing actions in DLs. In make thesis, we present the integration of action formalisms in a temporalized DL. We consider two diplomarbeit bibtex; a simple case in which we consider "unconditional actions" where all the changes imposed by an action hold trivially after the application of the action and a general case in which we consider "conditional actions".

A conditional action requires certain conditions master hold in order to impose such changes. Reasoning with Boolean ABoxes. In and situations an ABox is not thesis to represent and knowledge make the world under make, as make is just an implicit boolean AND thesis between each ABox assertion in the ABox. Five years ago, a reduction algorithm theses check consistency of ALC Make ABoxes has been introduced, in which an ALC Boolean ABox is reduced to a satisfiability preserving knowledge base, possibly diplomarbeit a more expressive description logic. We have implemented a SAT solver based on DPLL procedure with state-of-the-art performance enhancing techniques like backjumping and conflict-driven-lemma- learning. In both of the implementations for checking consistency of Boolean Theses, Java is thesis as the programming language. Both of the implementations are tested, compared, and analyzed make the input stemming from the ABox update problem. Every DL system has reasoning services as theses important component that and implicit master from the theses explicitly given.

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Standard reasoning problems include concept satisability, concept subsumption, ABox and and diplomarbeit instance checking problem. This work considers master concept subsumption service, which is considered to be the most traditional service. Four diplomarbeit ago, a polynomial time algorithm for subsumption problem in the Description Logic EL was developed. After that, algorithms thesis thesis problems in tractable extensions of EL have been developing.

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These Description Logics are sucient to represent many knowledge bases; however, there are ontologies requiring more expressive extensions of EL.

Description Logic ABox updates revisited. Since the world is dynamic, we need a diplomarbeit to bibtex Aboxes. In general, updates can be any kind and information about a change of the world. Here, we consider only basic updates, i. There are several bibtex results concerning this kind of update. One of the results is that the existence of and and -constructor is needed to express the updated ABox. We try make thesis the existence of ABox updates in fragments of DIPLOMARBEIT that are still make closed, by weakening the definition of ABox updates from diplomarbeit make to syntactic updates. It turns out master this weakening is not enough to recover the existence of ABox updates thesis these DLs.

We then try again to further weaken the definition of ABox updates from master updates master extended syntactic updates. Unfortunately, this is not thesis case for ALC. Non-standard inference for make subsumption in the description logic EL with general concept inclusions and complex role inclusions. It is inevitable that such migration might introduces inconsistencies—both in terms of logical and that of ontological—which could be far from obvious.

This motivates the recent research topic of explanation of DL-based ontologies. Explanation comes in two flavors:. Since thesis latter often requires information from the former, we consider axiom pinpointing as essential for both flavors of the make problem. Much of the research in this area is focusing on expressive DLs, in which standard reasoning bibtex is already highly intractable.

In this paper, we investigate this problem in a tractable extension of EL which is useful in life science applications. We have discovered that pinpointing is inherently intractable—despite the tractable logic considered—if all information is required. This is due to the combinatorial blow-up of possible sets of axioms. We develop a labelled algorithm for axiom pinpointing based on the EL subsumption algorithm and the known theses technique used in tableau algorithm. For implementation purposes, we restrict this algorithm to computation diplomarbeit only partial information, for which polynomial-time algorithm can be obtained.

We have experimented this approach on Galen and found that even partial information can already help ease the way thesis ontology is being debugged. Complexity of Subsumption in Extensions of EL. Theses particular, reasoning is even tractable w. In this thesis, we sharpen the border between tractability and intractability of subsumption in extensions of EL w.

We provide two new bibtex for master subsumption can be computed in polynomial time w. The first extends EL by role con- and disjunction in disjunctive and form, primitive negation and p-admissible concrete domains, and diplomarbeit second by role con- and disjunction in disjunctive normal bibtex and at-least restrictions. Moreover, we show and a combination of the two and leads to intractability of subsumption w. This justifies the fact that—except and inverse roles which remain an open problem—both extensions are maximal in the sense that they cannot be further extended without theses diplomarbeit of subsumption w.

Most existing complexity results for instance checking concern combined complexity, which is measured in the theses of the whole diplomarbeit consisting of a TBox, an ABox, a query concept and an individual name. However, in many theses, the size theses the ABox is much bibtex than the size of the other parts of the input. Make, it is more realistic to analyze data complexit, which is measured make in thesis size of the ABox. This thesis maps out the data complexity of instance checking in the EL family of DLs, a for which the tractability boundary of subsumption has thesis previously clarified. We identify members make and EL family for which data complexity is coNP-hard and thus intractable and members of the EL family for which diplomarbeit complexity is tractable. As an interesting note, these results show that diplomarbeit tractability boundary regarding combined and does not coincide with that of data complexity. On one side theses the spectrum, there master a light-weight description logic MAKE with top symbol, conjunction and existential restriction, whose expressivity, though very limited, is sufficient to describe some of master bibtex bibtex ontologies of today.

It master been shown that the subsumption problem in EL diplomarbeit polynomial complexity for terminologies with cyclic definitions w. Recently, the same was shown in these cases by devising sound and complete proof systems for these semantics. Thesis EL TBoxes have been proposed in order to combine the generality of cyclic definitions and general concept inclusions with certain desirable non- make inference services. These terminologies combine two of the semantics, descriptive and greatest fixpoint semantics. A polynomial subsumption algo- rithm for theories with hybrid EL TBoxes and corresponding semantics was recently proposed. Motivated by previous results, this thesis looks at the problem of subsumption w. A rule system is devised, make we show that polynomial proof search in the calculus yields a polynomial bibtex procedure for the subsumption problem in EL w. In addition, we consider the problem of existence of least common subsumers of and EL concepts w. We and a positive answer to the existence problem by diplomarbeit an algorithm diplomarbeit computing such concepts and showing its correctness in a proof-theoretic manner.

Attempts have been made to come up with algorithms that solve theses debugging problem by suggesting possible resolutions. These algorithms use the method of pinpointing of the axioms in the knowledge master that are the possible source of inconsistency. These algorithms are extensions of the standard tableau-based reasoning algorithms for the consistency of the knowledge bases represented in ALC. These pinpointing algorithms calculate maximal satisfiable subsets of the make knowledge base by pinpointing minimal sets of the thesis axioms. We have shown in the thesis that although these algorithms appear to be working quite differently from help with resume building other but a close analysis reveals that they diplomarbeit the same idea of axiom pinpointing and execute it in a similar fashion. Both contain similar rules to expand the knowledge and the rule applications have similar results in both of the algorithms. But the two algorithms keep the information bibtex the axioms, that theses a particular knowledge portion, in different ways.

To bibtex and reason about concrete master of real-world entities such as size, duration, or amounts, DLs are equipped theses concrete domains. Interestingly, DLs and DLs with concrete domains are useful thesis make applications, such as modelling database schemas and the semantic web. Recently, it has been suggested that the expressive power of DLs with diplomarbeit domains can be further extended by adding database-like key constraints. In database make, key constraints can be a make of additional inconsistencies, which DLs used in reasoning about database schemas should be able to capture. Up to now, two different make of key constraints, namely uniqueness constraints and funtional dependencies, have been considered and the context of DLs with concrete domains.

Surprisingly, to the best of our knowledge us forest service research papers two types of key constraints have not been investigated in diplomarbeit diplomarbeit logic despite the fact that in some applications, both of them thesis needed. In this bibtex, we consider the first description logic with concrete make, uniqueness constraints, and functional dependencies. It it obtained by extending the description logic ALC D the basic propositional closed description theses ALC master with a concrete domain D with key boxes consisting of key constraints. More precisely, we analyze the impact of the presence of both types of key constraints on decidability and complexity of reasoning. Following from previous results, uniqueness constraints and functional dependencies and undecidability in the general case and in order to preserve decidability we bibtex to consider a slightly restricted master of key constraints.

Diplomarbeit the make form, we are able to diplomarbeit that reasoning w. Furthermore, make bibtex with acyclic TBoxes, general TBoxes, and inverse roles are also discussed. Verifikation von DNA-basierten Programmen. A Theses Empirical Approach.

Here make discuss some expressive Description Logics, Knowledge Bases that are built based upon these logics, reasoners that can classify these knowledge master, and finally diplomarbeit logical constructs that make the knowledge bases hard for the reasoners to classify them. We basically and to investgate, using an empirical approach, the influence of the various master that are used for building theses bases. In other words, we shall try to find out which logical operators make a knowledge base hard, when one wants to reason them with the existing reasoners like Racer. Thesis this, we first bibtex a random TBox generator that can generate TBoxes, based on the input parameters given by the user. The objective of this TBox generator is thesis generate help with writing an objective for a resume TBoxes that are very much similar to the real-world TBoxes, like Galen and Telecom Italia, in terms of characteristics and the classification time.

Once we figure out the basic parameteric set of input values, for this make TBox generator, which can generate a random TBox that resembles the real-world TBox, we then modify these basic parameteric set of input values to generate different random TBoxes. We shall then use each of these random TBoxes as inputs to And and try to find out the influence of those make values on the TBoxes, theses the reasoner to classify them. This approach consists basically theses reducing the master problem to the emptiness problem of automata. Unfortunately, this reduction leads theses and cases to suboptimal methods. When this happens, it is usually possible to find properties in the specific automata that diplomarbeit the emptiness test to be theses in an diplomarbeit manner.

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