1.

Artificial Intelligence 128 (2001) 203–235 A logic-based theory of deductive arguments ✩
- Anthony Hunter B
We explore a framework for argumentation (based on classical logic) in which an argument is a pair where the first item in the pair is a minimal consistent set of formulae that proves the second item (which is a formula). We provide some basic definitions for arguments, and various kinds of counter-arguments (defeaters). This leads us to the definition of canonical undercuts which we argue are the only defeaters that we need to take into account. We then motivate and formalise the notion of argument trees and argument structures which provide a way of exhaustively collating arguments and counter-arguments. We...

2.

Declarative languages -- paradigm of the past or challenge of the future
- Rainer Manthey
Declarative database query languages have recently been criticized by the research community. Proponents of database programming languages and objectoriented databases recommended doing away with declarative means for specifying retrieval, except for perhaps ad-hoc querying. Supporters of deductive databases and logic programming want to extend declarative query languages into full programming languages while retaining dedarativity. It is our conviction that neither approach will lead to a satisfactory solution. We claim instead that languages offeting both paradigms in full extension are desirable and can be achieved without suffering from the drawbacks encountered when simply combining existing query and programming languages. In this...

3.

kLog -- A Language for Logical and Relational Learning with Kernels
- Paolo Frasconi; Fabrizio Costa; Luc De Raedt; Kurt De Grave
kLog is a logical and relational language for kernel-based learning. It allows users to specify logical and relational learning problems at a high level in a declarative way. It builds on simple but powerful concepts: learning from interpretations, entity/relationship data modeling, logic programming and deductive databases (Prolog and Datalog), and graph kernels. kLog is a statistical relational learning system but unlike other statistical relational learning models, it does not represent a probability distribution directly. It is rather a kernel-based approach to learning that employs features derived from a grounded entity/relationship diagram. These features are derived using a novel technique called...

4.

A Transformation Technique for Datalog Programs Based on Non-Deterministic Constructs
- Petros Potikas; Panos Rondogiannis; Manolis Gergatsoulis
Recently, a novel transformation technique for Datalog programs, called the branching transformation, was introduced by the authors. In this paper we propose a significant extension of the branching transformation which we believe opens-up a promising new direction of research in the area of value-propagating Datalog optimizations. One of the novel characteristics of the proposed approach is that the target language is DatalognS extended with choice predicates, a form of non-deterministic construct that was originally introduced in the area of intensional logic programming. Keywords: Logic Program Transformations, Deductive Databases. 1

5.

The Branching-Time Transformation Technique for Chain Datalog Programs
- Panos Rondogiannis; Manolis Gergatsoulis
The branching-time transformation technique has proven to be an efficient approach for implementing functional programming languages. In this paper we demonstrate that such a technique can also be defined for logic programming languages. More specifically, we first introduce Branching Datalog, a language that can be considered as the basis for branching-temporal deductive databases. We then present a transformation algorithm from Chain Datalog programs to the class of unary Branching Datalog programs with at most one IDB atom in the body of each clause. In this way, we obtain a novel implementation approach for Chain Datalog, shedding at the same time...

6.

INDALOG: A Declarative Deductive Database Language
- Jesús M. Almendros-Jiménez; Antonio Becerra-Terón
In this paper we present the main features of a deductive database language named INDALOG based on the integration of functional and logic paradigms. As most deductive database systems, INDALOG allows the handling of negation, higher-order functions, grouping operators, support for aggregation, handling of non-ground facts, and support for indexing structures on both extensional and intensional relations of a database. Moreover, we present the semantic foundations of this language. 1

7.

Exstensions of Deductive Concept in Logic Programing and Some Applications
- Ivana Berković; Biljana Radulović; Petar Hotomski
Abstract. The paper presents ATP – a system for automated theorem proving based on ordered linear resolution with marked literals, its putting into the base of prolog-like language and some applications. This resolution system is especially put into the base of prolog-like language, as the surrogate for the concept of negation as definite failure. This logical complete deductive base is used for building a descriptive logical programming language LOGPRO, which enables eliminating the defects of PROLOG-system (the expansion concerning Horn clauses, escaping negation treatment as definite failure), but keeping the main properties of PROLOG-language and possibilities of its expansions. Some...

8.

What you always wanted to know about Datalog (and never dared to ask
- Stefan Ceri; Georg Gottlob; Letizia Tanca
Abstract-Datalog is a database query language based on the logic programming paradigm; it has been designed and intensively studied over the last five years. We present the syntax and semantics of Datalog and its use for querying a relational database. Then, we classify optimization methods for achieving efficient evaluations of Datalog queries, and present the most relevant methods. Finally, we discuss various exhancements of Datalog, currently under study, and indicate what is still needed in order to extend Datalog’s applicability to the solution of real-life problems. The aim of this paper is to provide a survey of research performed on...

9.

A Transformation Technique for Datalog Programs Based on Non-Deterministic Constructs
- Petros Potikas; Panos Rondogiannis; Manolis Gergatsoulis
Recently, a novel transformation technique for Datalog programs, called the branching transformation, was introduced by the authors. In this paper we propose a signicant extension of the branching transformation which we believe opens-up a promising new direction of research in the area of value-propagating Datalog optimizations. One of the novel characteristics of the proposed approach is that the target language is DatalognS extended with choice predicates, a form of non-deterministic construct that was originally introduced in the area of intensional logic programming. Keywords: Logic Program Transformations, Deductive Databases. 1

10.

Logic and Databases
- Johann Eder
Logic and databases have gone a long way together since the advent of relational databases. Already the first basic query languages for relational databases beside relational algebra - tuple calculus and domain calculus - are actually a subset of first order predicate logic. Furthermore logic proved to be very adequate for establishing a sound theory for relational databases. When attempts were made to integrate AI and database technology in form of expert database systems or knowledge base management systems logic provided a unifying framework although several differences in the use of logic in the both fields have been discovered. The...

11.

Extending Classical Logic with Inductive Definitions
- Marc Denecker
The goal of this paper is to extend classical logic with a generalized notion of inductive definition supporting positive and negative induction, to investigate the properties of this logic, its relationships to other logics in the area of non-monotonic reasoning, logic programming and deductive databases, and to show its application for knowledge representation by giving a typology of definitional knowledge.

12.

Extending Classical Logic with Inductive Definitions
- Marc Denecker
The goal of this paper is to extend classical logic with a generalized notion of inductive definition supporting positive and negative induction, to investigate the properties of this logic, its relationships to other logics in the area of non-monotonic reasoning, logic programming and deductive databases, and to show its application for knowledge representation by giving a typology of definitional knowledge.

13.

Revising Horn Theories
- James P. Delgrande; Pavlos Peppas
This paper investigates belief revision where the underlying logic is that governing Horn clauses. It proves to be the case that classical (AGM) belief revision doesn’t immediately generalise to the Horn case. In particular, a standard construction based on a total preorder over possible worlds may violate the accepted (AGM) postulates. Conversely, Horn revision functions in the obvious extension to the AGM approach are not captured by total preorders over possible worlds. We address these difficulties by first restricting the semantic construction to “well behaved” orderings; and second, by augmenting the revision postulates by an additional postulate. This additional postulate...

14.

A Buchholz Rule for Modal Fixed Point Logics
- Gerhard Jäger; Thomas Studer
Buchholz’s Ωµ+1-rules provide a major tool for the proof-theoretic analysis of arithmetical inductive definitions. The aim of this paper is to put this approach into the new context of modal fixed point logic. We introduce a deductive system based on an Ω-rule tailored for modal fixed point logic and develop the basic techniques for establishing soundness and completeness of the corresponding system. In the concluding section we prove a cut elimination and collapsing result similar to that of Buchholz [3].

15.

Super Logic Programs
- Stefan Brass; Jürgen Dix; Teodor C. Przymusinski
Recently, considerable interest and research e#ort has been given to the problem of finding a suitable extension of the logic programming paradigm beyond the class of normal logic programs. In order to demonstrate that a class of programs can be justifiably called an extension of logic programs one should be able to argue that: . the proposed syntax of such programs resembles the syntax of logic programs but it applies to a significantly broader class of programs; . the proposed semantics of such programs constitutes an intuitively natural extension of the semantics of normal logic programs; . there exists a...

16.

Paraconsistent Logic Programs
- João Alcântara; Carlos Viegas Damásio; Luís Moniz Pereira
We propose a framework which extends Antitonic Logic Programs [3] to an arbitrary complete bilattice of truth-values, where belief and doubt are explicitly represented. Based on Fitting's ideas, this framework allows a precise definition of important operators found in logic programming such as explicit negation and the default negation. In particular, it leads to a natural integration of explicit negation with the default negation through the coherence principle [20]. According to this principle, the explicit negation entails the default negation. We then define Coherent Answer Sets, and the Paraconsistent Well-founded Model semantics, generalizing paraconsistent semantics for logic programs (for instance,...

17.

Antitonic Logic Programs
- Carlos Viegas Damásio; Luís Moniz Pereira
In a previous work we have de ned Monotonic Logic Programs which extend de nite logic programming to arbitrary complete lattices of truth-values with an appropriate notion of implication. We have shown that this framework is general enough to capture Possibilistic Logic Programming, Hybrid Probabilistic Logic Programs, Fuzzy Logic Programming, Probabilistic Deductive Databases, and Generalized Annotated Logic Programs. However, none of these semantics de ne a form of non-monotonic negation, which is fundamental for several knowledge representation applications. In the spirit of our previous work, we generalise our framework of Monotonic Logic Programs to allow for rules with arbitrary antitonic...

18.

An Experimental Study on the Complexity of Left-Deep Join Ordering Problems for Cyclic Queries
- Birgitta König-Ries; Sven Helmer; Guido Moerkotte
Not only in deductive databases, logic programming, and constraint satisfaction problems but also in object bases where each single dot in a path expression corresponds to a join, the optimizer is faced with the problem of ordering large numbers of joins. This might explain the renewed interest in the join ordering problem. Although many join ordering techniques have been invented and benchmarked over the last years, little is known on the actual effectiveness of the developed methods and the cases where they are bound to fail. The problem attacked is the discovery of parameters and their qualitative influence on the...

19.

Motivação dos servidores públicos: um caso na saúde pública na Amazônia
- Oliveira, Tiago Luz; Silva, Luis Cláudio de Jesus
For some time, many management scholars, along with researchers from other fields such as psychology and economics, concentrate their studies in understanding the factors related to quality of work life. This new look, just illustrates the great importance of human resources for organizations, highlighting the need to attract and keep people motivated
and satisfied with and to work. In this article the aim is to identify the levels and main factors that cause satisfaction and dissatisfaction in the work of civil servants of the Ministry of Health of Roraima - SESAU / RR. In the literature review, and conceptualize people management...

20.

A Sequent Calculus for Intuitionistic Default Logic
- Uwe Egly; Hans Tompits
Current research on non-monotonic reasoning shows growing interest on implementation details, so the need for concrete calculi formalizing non-monotonic logics is clearly recognized. On the other hand, there is also an increased number of works combining intuitionistic logic with various kinds of non-monotonic formalisms. As a case in point, intuitionistic versions of both default and autoepistemic logics have been proposed, and tight connections between intuitionistic logic and logic programs (or deductive databases) using hypothetical inferences have been established. In this paper, we present a sequent calculus for default reasoning in the style of Bonatti with intuitionistic logic as the underlying...