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This paper presents an agile method of logical semantics based on high-order Predicate Logic. An operator of predicate abstraction is introduced that provides a simple mechanism for logical aggregation of predicates and for logical typing. Monadic high-order logic is the natural environment in which predicate abstraction expresses the semantics of typical linguistic structures. Many examples of logical representations of natural language sentences are provided. Future extensions and possible applications in the interaction with chatbots are briefly discussed as well. [ABSTRACT FROM AUTHOR]

This paper proposes a framework for time-efficiently finding multiple answers that meet multiple logical constraints and are Pareto-optimal for multiple objective functions. The proposed framework determines a set of optimal answers by iteratively replacing a set of definite clauses. Clause replacement is performed using a SAT solver consisting of equivalent transformation rules (ETRs). An ETR replaces a definite clause with one or more clauses while preserving the declarative meaning of the union of the original clause and problem clauses. To efficiently find optimal answers, in this paper, we define a new class of ETRs that are generated based on the evaluation results of a multi-objective genetic algorithm (MOGA) and propose a method for generating ETRs that belong to the new class. ETRs belonging to the new class help to replace definite clauses according to user objectives such as cost–benefit performance, reliability, and financial constraints. Thus, a SAT solver that uses the new ETR class in addition to extant ETR classes can preferentially replace definite clauses that produce the optimal answer for user objectives. Experimental results indicate that the proposed framework can significantly reduce the computation time and memory usage necessary to determine a set of optimal answers for user objectives. [ABSTRACT FROM AUTHOR]

A notion of strictly primitive recursive realizability is introduced by Damnjanovic in 1994. It is a kind of constructive semantics of the arithmetical sentences using primitive recursive functions. It is of interest to study the corresponding predicate logic. It was argued by Park in 2003 that the predicate logic of strictly primitive recursive realizability is not arithmetical. Park's argument is essentially based on a claim of Damnjanovic that intuitionistic logic is sound with respect to strictly primitive recursive realizability, but that claim was disproved by the author of this article in 2006. The aim of this paper is to present a correct proof of the result of Park. [ABSTRACT FROM AUTHOR]

Due to the lack of language analysis and understanding algorithms for kinematics problems, researches on automatic algorithms for tutorial systems are mainly concentrated on mathematics and physical circuits, and these algorithms are still represented by frame solution and semantic analysis. Additionally, these methods need to design rule templates to understand the complex text, which leads to the low efficiency of solving. Although deep learning (DL) have be applied to machine answers, but it is difficult to achieve the integration of problem understanding, reasoning, and solving through a generic framework. Therefore, this paper proposes a high-performance algorithm to understand and solve kinematics problems. By dividing solving kinematics problems into two stages: understanding and solving, we propose a unified framework for solving kinematic problems. Firstly, we transform understanding into relation extraction (RE), and propose a RE algorithm combining named entity recognition (NER) and first order logic (FOL) based on a novel tagging schema to extract overlapping relation in kinematics texts. For the solving stage, a backward chain reasoning algorithm based on meta-information is presented to solve kinematics problems. Additionally, three levels of comprehension and two conditions for measuring levels of comprehension are proposed to evaluate the performance of the proposed system. Finally, based on the evaluation metrics proposed in this paper, verification experiments are carried out on a dataset of kinematic problems from an authoritative source. And the results show that the proposed algorithm successfully solves 92.52% of the kinematic problems, which is higher than the baseline algorithms. [ABSTRACT FROM AUTHOR]

Enterprise modeling deals with the increasing complexity of processes and systems by operationalizing model content and by linking complementary models and languages, thus amplifying the model value beyond mere comprehensible pictures. To enable this amplification and turn models into computer-processable structures, a comprehensive formalization is needed. This paper presents the formalism MetaMorph based on typed first-order logic and provides a perspective on the potential and benefits of formalization that arise for a variety of research issues in conceptual modeling. MetaMorph defines modeling languages as formal languages with a signature Σ —comprising object types, relation types, and attributes through types and function symbols—and a set of constraints. Four case studies are included to show the effectiveness of this approach. Applying the MetaMorph formalism to the next level in the hierarchy of models, we create M2FOL, a formal modeling language for metamodels. We show that M2FOL is self-describing and therefore complete the formalization of the full four-layer metamodeling stack. On the basis of our generic formalism applicable to arbitrary modeling languages, we examine four current research topics—modeling with power types, language interleaving & consistency, operations on models, and automatic translation of formalizations to platform-specific code—and how to approach them with the MetaMorph formalism. This shows that the rich knowledge stack on formal languages in logic offers new tools for old problems. [ABSTRACT FROM AUTHOR]

Association rule mining (ARM) is used for discovering frequent itemsets for interesting relationships of associative and correlative behaviors within the data. This gives new insights of great value, both commercial and academic. The traditional ARM techniques discover interesting association rules based on a predefined minimum support threshold. However, there is no known standard of an exact definition of minimum support and providing an inappropriate minimum support value may result in missing important rules. In addition, most of the rules discovered by these traditional ARM techniques refer to already known knowledge. To address these limitations of the minimum support threshold in ARM techniques, this study proposes an algorithm to mine interesting association rules without minimum support using predicate logic and a property of a proposed interestingness measure (g measure). The algorithm scans the database and uses g measure's property to search for interesting combinations. The selected combinations are mapped to pseudo-implications and inference rules of logic are used on the pseudo-implications to produce and validate the predicate rules. Experimental results of the proposed technique show better performance against state-of-the-art classification techniques, and reliable predicate rules are discovered based on the reliability differences of the presence and absence of the rule's consequence. [ABSTRACT FROM AUTHOR]

In Berto's logic for aboutness in imagination, the output content of an imaginative episode must be part of the initial content of the episode (Berto, Philos Stud 175:1871–1886, 2018). This condition predicts expressions of perfectly legitimate imaginative episodes to be false. Thus, this condition is too strict. Relaxing the condition to correctly model these cases requires to consider a language with predicates and constants. The paper extends Berto's semantics for aboutness in imagination to a semantics for such a language. The new semantics models contents of formulas along the lines of Hawke's issue-based theory of topics (Hawke, Australas J Philos 96:697–723, 2017), while remaining faithful to the (in)validities discussed by Berto. Several relations between issues and topics are defined, which allow to overcome shortcomings of Hawke's initial framework. These relations are then discussed with respect to their usefulness in the truth condition for the imagination operator. [ABSTRACT FROM AUTHOR]

In this article, I build an actantial model, M , of John Cage's 1962 indeterminate work 0 ′ 00 ′ ′ (4 ′ 33 ′ ′ No. 2). To further investigate Greimas' actantial axes of desire, knowledge and power, I generate an ontology, O , that records the facts of the model through hierarchies of relations and concepts. This allows for a conceptual graph (CG), C , that describes the score's instructions and its actants. Extracting subgraphs of C then allows for reasoned arguments about the implications of Cage's instructions in the score, and in particular, the composer's reference to "an obligation to others." Through a conceptual graph rule R , I offer a framework for generating the structure of a score-informed interpretation of 0 ′ 00 ′ ′ (4 ′ 33 ′ ′ No. 2) that is based on a number of key conditionals that map the actants of the piece and their relation to the unfolding of the work's narrative. [ABSTRACT FROM AUTHOR]

Copyright of Acta Linguistica Asiatica is the property of Acta Linguistica Asiatica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We introduce unification in first-order logic. In propositional logic, unification was introduced by S. Ghilardi, see Ghilardi (1997, 1999, 2000). He successfully applied it in solving systematically the problem of admissibility of inference rules in intuitionistic and transitive modal propositional logics. Here we focus on superintuitionistic predicate logics and apply unification to some old and new problems: definability of disjunction and existential quantifier, disjunction and existential quantifier under implication, admissible rules, a basis for the passive rules, (almost) structural completeness, etc. For this aim we apply modified specific notions, introduced in propositional logic by Ghilardi, such as projective formulas, projective unifiers, etc. Unification in predicate logic seems to be harder than in the propositional case. Any definition of the key concept of substitution for predicate variables must take care of individual variables. We allow adding new free individual variables by substitutions (contrary to Pogorzelski & Prucnal (1975)). Moreover, since predicate logic is not as close to algebra as propositional logic, direct application of useful algebraic notions of finitely presented algebras, projective algebras, etc., is not possible. [ABSTRACT FROM AUTHOR]

In this paper, we study finitely axiomatizable conservative extensions of a theory U in the case where U is recursively enumerable and not finitely axiomatizable. Stanisław Krajewski posed the question whether there are minimal conservative extensions of this sort. We answer this question negatively. Consider a finite expansion of the signature of U that contains at least one predicate symbol of arity ≥ 2. We show that, for any finite extension α of U in the expanded language that is conservative over U , there is a conservative extension β of U in the expanded language, such that α |-- β and β {not}|-- α. The result is preserved when we consider either extensions or model-conservative extensions of U instead of conservative extensions. Moreover, the result is preserved when we replace --| as ordering on the finitely axiomatized extensions in the expanded language by a relevant kind of interpretability, to wit interpretability that identically translates the symbols of the U-language. We show that the result fails when we consider an expansion with only unary predicate symbols for conservative extensions of U ordered by interpretability that preserves the symbols of U. [ABSTRACT FROM AUTHOR]

We study a modal extension of the Continuous First-Order Logic of Ben Yaacov and Pedersen (J Symb Logic 75(1):168-190, 2010). We provide a set of axioms for such an extension. Deduction rules are just Modus Ponens and Necessitation. We prove that our system is sound with respect to a Kripke semantics and, building on Ben Yaacov and Pedersen  (2010), that it satisfies a number of properties similar to those of first-order predicate logic. Then, by means of a canonical model construction, we get that every consistent set of formulas is satisfiable. From the latter result we derive an Approximated Strong Completeness Theorem, in the vein of Continuous Logic, and a Compactness Theorem. [ABSTRACT FROM AUTHOR]

Models of complex systems are widely used in the physical and social sciences, and the concept of layering, typically building upon graph-theoretic structure, is a common feature. We describe an intuitionistic substructural logic called ILGL that gives an account of layering. The logic is a bunched system, combining the usual intuitionistic connectives, together with a non-commutative, non-associative conjunction (used to capture layering) and its associated implications. We give soundness and completeness theorems for a labelled tableaux system with respect to a Kripke semantics on graphs. We then give an equivalent relational semantics, itself proven equivalent to an algebraic semantics via a representation theorem. We utilise this result in two ways. First, we prove decidability of the logic by showing the finite embeddability property holds for the algebraic semantics. Second, we prove a Stone-type duality theorem for the logic. By introducing the notions of ILGL hyperdoctrine and indexed layered frame we are able to extend this result to a predicate version of the logic and prove soundness and completeness theorems for an extension of the layered graph semantics. We indicate the utility of predicate ILGL with a resource-labelled bigraph model. [ABSTRACT FROM AUTHOR]

In §93 of The Principles of Mathematics, Bertrand Russell (1903) observes that “the variable is a very complicated logical entity, by no means easy to analyze correctly”. This assessment is borne out by the fact that even now we have no fully satisfactory understanding of the role of variables in a compositional semantics for first-order logic. In standard Tarskian semantics, variables are treated as meaning-bearing entities; moreover, they serve as the basic building blocks of all meanings, which are constructed out of variable assignments. But this has disquieting consequences, including Fine’s antinomy of the variable and an undue dependence of meanings on language (representationalism). Here I develop an alternative, Fregean version of predicate logic that uses the traditional quantifier–variable apparatus for the expression of generality, possesses a fully compositional, non-representational semantics, and is not subject to the antinomy of the variable. The advantages of Fregean over Tarskian predicate logic are due to the former’s treating variables not as meaningful lexical items, but as mere marks of punctuation, similar to parentheses. I submit that this is indeed how the variables of predicate logic should be construed [ABSTRACT FROM AUTHOR]

The power of data dependence testing techniques of a parallelizing compiler is its essence to transform and optimize programs. Numerous techniques were proposed in the past, and it is, however, still a challenging problem to evaluate the relative power of these techniques to better understand the data dependence testing problem. In the past, either empirical studies or experimental evaluation results are published to compare these data dependence testing techniques, being not able to convince the research community completely. In this paper, we show a theoretical study on this issue, comparing the power on disproving dependences of existing techniques by proving theorems in a proposed formal system K-DT. Besides, we also present the upper bounds of these techniques and introduce their minimum complete sets. To the best of our knowledge, K-DT is the first formal system used to compare the power of data dependence testing techniques, and this paper is the first work to show the upper bounds and minimum complete sets of data dependence testing techniques. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to give some insights into the immense role of Frege's first order logic (FOL) in the development of computer science. We argue that the FOL is fundamental in computer science, and that some computer science subfields could not have existed without their theoretical foundations built on this form of logic. Among these subfields, one can mention the Type Theory, Databases, Descriptive Complexity, Artificial Intelligence, Logic Programming, and Automated Theorem Proving. To illustrate our point, an in-depth attention will in particular be given to the foundational development of the most popular logic programming language, PROLOG, and the Automated Theorem Proving (ATP) systems. Importantly, when studying the interactions between logic and computer science in the literature, we can observe a significant gap in the provision of the appropriate abstraction level. Specifically, we often encounter two different levels of abstraction. The first of these is relatively high even when describing technical notions in computer science, which obviously produces a lack of precision. The second adopts a technical-oriented approach which easily makes the topic and discussion unintuitive or inaccessible to the non-specialist. The paper attempts to remedy these problems by adopting a balanced approach that provides a moderate level of abstraction that targets a deeper understanding of the topic without imposing a very technical presentation on the reader. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a proof system NQGL for a Kripke complete predicate extension of the logic GL of provability. While GL is defined by K and the Lβb formula ✷(✷p ⊃ p) ⊃ ✷p, NQGL does not have the Lβb formula as its axiom, but has a non-compact rule, that is, a derivation rule with countably many premises, instead. We show that NQGL enjoys cut admissibility and is complete with respect to the class of Kripke frames such that for each world, the supremum of the length of the paths from the world is finite. [ABSTRACT FROM AUTHOR]

Copyright of Informatics & Mathematical Methods in Simulation / Informatika ta Matematičnì Metodi v Modelûvannì is the property of Odessa Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A chemical substance (CS) is instantiated in the material world by a number of quantities of such substance (QCSs), placed in different locations. A change of location implies a change in the net of relationships entertained by the QCS with the region wherein it is found. This fact entails changes of the ontological status of the CS, as this is not fully determined by the inherent features of the CS and includes a relevant relational contribution. In order to demonstrate this thesis, we have chosen to analyse the status of quantities of a same CS that are synchronically located in different spacetime regions: a synthetic lab, a lab where the QCS is turned into a material, an industrial plant, the market where the QCS gets a price and a dump waste where the QCS is discarded, respectively: The use of first-order predicate logic, mereology and locative logic allows carrying out a regimentation process that highlights the ontological commitments implied by the formal expressions through which each element of the aforementioned series can be described. The presence of relational properties discloses the systemic nature of the CS instantiated within a spacetime region. The implications of such an aspect are discussed. [ABSTRACT FROM AUTHOR]

This is a companion to a paper by the authors entitled “Gödel’s natural deduction,” which presented and made comments about the natural deduction system in Gödel’s unpublished notes for the elementary logic course he gave at the University of Notre Dame in 1939. In that earlier paper, which was itself a companion to a paper that examined the links between some philosophical views ascribed to Gödel and general proof theory, one can find a brief summary of Gödel’s notes for the Notre Dame course. In order to put the earlier paper in proper perspective, a more complete summary of these interesting notes, with comments concerning them, is given here. [ABSTRACT FROM AUTHOR]

This paper presents a formal approach to verifying Error Correction Code (ECC) processors based on Galois-Field (GF) arithmetic. The proposed method describes GF arithmetic circuits by graph-based representation, called Galois-Field Arithmetic Circuits Graph (GF-ACG), and verifies them by a combination of an algebraic method with a new verification method based on natural deduction for the first-order predicate logic with equal sign. The natural deduction method is suitable for higher-degree GF arithmetic circuits such as in ECC decoders while the conventional methods requires enormous time to verify them or sometimes cannot verify them. In this paper, we apply the proposed method to the design and verifications of various Reed-Solomon (RS) code encoders and decoders. In particular, we confirm that the proposed method can verify RS code decoders with higher-degree functions while the conventional method fails. [ABSTRACT FROM AUTHOR]

Copyright of Sistemas & Telemática is the property of Universidad ICESI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A scalable, reactive and easy to evolve reasoning mechanism is essential for the success of automated smart environments, augmented with a large number of sensors and actuators. While constraint satisfaction problem (CSP) model is applicable for modelling decision making in such environments, the straightforward representation of the model as a CSP leads to a great number of excessive calculations. In this paper, we propose a method of modelling the task as a Dynamic CSP in a way that avoids unnecessary recalculations with new events in the environment. We present a Dependency Graph data structure, which not only allows to reduce CSP search space for every consecutive sensor event by detecting only affected parts of the environment, but also allows to give enough information to users of the system to specify the exact reasons of system's decisions, even with a large number of constraints. We formally prove that partial recalculation of affected parts still keeps the full environment globally satisfied and globally optimal. The evaluation of the system in the living lab showed real-time responses for all events. Additional simulated performance experiments showed that the Dependency Graph approach consistently outperforms the straightforward CSP representation. The experiments also showed that the clusterization of the environment has a noticeable effect on the performance, with highly clusterized environments requiring less computations. [ABSTRACT FROM AUTHOR]

Frege explained the notion of generality by stating that each its instance is a fact, and added only later the crucial observation that a generality can be inferred from an arbitrary instance. The reception of Frege’s quantifiers was a fifty-year struggle over a conceptual priority: truth or provability. With the former as the basic notion, generality had to be faced as an infinite collection of facts, whereas with the latter, generality was based on a uniformity with a finitary sense: the provability of an arbitrary instance. [ABSTRACT FROM PUBLISHER]

Earthquake is a natural disaster which causes extensive damage as well as the death of thousands of people. Earthquake professionals for many decades have recognized the benefits to society from reliable earthquake predictions. Techniques like: mathematical modelling, hydrology analysis, ionosphere analysis and even animal responses have been used to forecast a quake. Most of these techniques rely on certain precursors like, stress or seismic activity. Data mining techniques can also be used for prediction of this natural hazard. Data mining consists of evolving set of techniques such as association rule mining that can be used to extract valuable information and knowledge from massive volumes of data. The aim of this study is to predict a subsequent earthquake from the data of the previous earthquake. This is achieved by applying association rule mining on earthquake data from 1979 to 2012. These associations are polished using predicate-logic techniques to draw stimulating production-rules to be used with a rule-based expert system. Prediction process is done by an expert system, which takes only current earthquake attributes to predict a subsequent earthquake. The rules generated for predicting the earthquake are mathematically validated as well as tested on real life earthquake data. Results from our study show that the proposed rule-based expert system is able to detect 100 % of earthquakes which actually occurred within 15 hours at-most within a defined range, depth and location. This work solely relies on previous earthquake data for predicting the next. [ABSTRACT FROM AUTHOR]

The paper discusses several theoretical and implementational problems of interval branch-and-bound methods. A trial to define a class of problems that can be solved with such methods is done. Features and variants of the method are presented. Useful data structures and shared-memory parallelization issues are considered. [ABSTRACT FROM AUTHOR]

There are two implicit semantic postulates underlying modern predicate logic. Hence predicate logic is not semantically neutral. The author proposes to take semantically neutral languages, which have no predicate categorial structure but replace the notion of predicate with general notion of function. Some function calculi for different semantics are demonstrated. [ABSTRACT FROM AUTHOR]

Predicate logic gates, components and a processor are proposed for space-time signals and computing. Voltage impulses are transmitted along two wires and the signals are considered as predicate expressions. The developed simple gates and components perform the predicate logical operations AND, NOT, and OR with these expressions. For design and verification of all components and the processor, the CPLD and FPGA boards and corresponding software are used. The designed processor is compatible with classical computers and applicable in the area of artificial intelligence as well as linguistic calculations, database machines, SQL servers, etc. [ABSTRACT FROM AUTHOR]

Part machining is a discrete manufacturing process. In order to evaluate the manufacturing process, an intelligent modeling method based on the first-order predicate logic is proposed. First, the basic predicate formula is defined according to the machining method, and the predicate and variables are illustrated in detail. Thus, the process representation is completed. Second, to construct the process model, the modeling element is put forward, which includes three nodes. Components of modeling element are, respectively, discussed, as well as the mapping relationship between modeling element and predicate. After the definition of modeling predicate formula, five basic inference rules are established. Consequently, the manufacturing process model is constructed. Third, on the basis of the process model, the process simulation is carried out to evaluate the manufacturing performances, such as the production efficiency, the utilization rate of machining equipment, the production bottleneck, etc. Finally, a case study is conducted to explain this modeling method. [ABSTRACT FROM AUTHOR]

The goal of Aspect-Oriented Requirements Engineering is to identify possible crosscutting concerns, and to develop composition specifications, which can be used to reason about potential conflicts in the requirements. Recent work in AORE has moved from a syntactic approach to composition, which leads to fragile compositions and increased coupling between aspect and base concerns, to a semantic composition approach, based on semantics of the natural language itself. However, such compositions are at present only informally specified, and as such precise conflict detection between the requirements compositions is difficult. We present an approach for the formalisation of these semantic-based compositions which means that logical conflicts between compositions can be precisely identified and understood semantically. We show that the approach can be supported by off-the-shelf tools, meaning it is scalable and feasible for even large requirements specifications. [ABSTRACT FROM AUTHOR]

Many security problems are caused by vulnerabilities hidden in enterprise computer networks. It is very important for system administrators to have knowledge about the security vulnerabilities. However, current vulnerability assessment methods may encounter the issues of high false positive rates, long computational time, and requirement of developing attack codes. Moreover, they are only capable of locating individual vulnerabilities on a single host without considering correlated effect of these vulnerabilities on a host or a section of network with the vulnerabilities possibly distributed among different hosts. To address these issues, an active vulnerability assessment system NetScope with C/S architecture is developed for evaluating computer network security based on open vulnerability assessment language instead of simulating attacks. The vulnerabilities and known attacks with their prerequisites and consequences are modeled based on predicate logic theory and are correlated so as to automatically construct potential attack paths with strong operation power of relational database management system. The testing results from a series of experiments show that this system has the advantages of a low false positive rate, short running periods, and little impact on the performance of audited systems and good scalability. The security vulnerabilities, undetectable if assessed individually in a network, are discovered without the need to simulate attacks. It is shown that the NetScope system is well suited for vulnerability assessment of large-scale computer networks such as campus networks and enterprise networks. Moreover, it can also be easily integrated with other security tools based on relational databases. [ABSTRACT FROM AUTHOR]

In this paper, I will discuss a certain conception of matter that Aristotle introduces in Metaphysics Z3. It is often assumed that Aristotle came to distinguish between matter and form only in his physical writings, and that this lead to a conflict with the doctrine of primary substances in the Categories that he tries to resolve in Z3. I will argue that there is no such conflict. In Z3, Aristotle seems to suggest that matter is what is left over when we strip a thing of all its properties. I take it that he does not want us to strip away these properties by physical means or in our imagination. Rather, we are asked to strip a referring noun phrase of all its predicative parts. We are thus not supposed to be able to refer to something that has no qualities whatsoever, but to construct a phrase that refers to something that has properties without referring to its having them, and without implying which properties it has. The idea that there might be a way of referring to something definite without mentioning any of its qualities is platonic and it still underlies modern predicate logic. In Z3, Aristotle argues against this conception and thus against the basic idea of predicate logic. According to him, matter is at best an inseparable aspect of a primary substance, which substance is best referred to as a compound τóδε τι (“this such”). Matter is what the τóδε refers to as part of this phrase. But it cannot exist in separation from form, and we cannot refer to it by a separated term, without also referring to the substantial form of the substance of which it is an aspect. [ABSTRACT FROM AUTHOR]

The work described in this paper relates to the formal description, implementation and use of a web-based personalized assessment system. The assessment techniques are formalized with First Order Logic rules which are able to reason over resources annotated with Semantic Web metadata formats according to LOM and IMS/ QTI standards. They were tested using TRIPLE, a rule-based language for the Semantic Web. We also describe the service-based architecture, which was implemented as part of the Personal Reader Framework. Personalization functionalities are available as web services that communicate via Semantic Web technologies without the need for centralized control. Appropriate assessment resources are searched after checking the learner's last saved performance. We illustrate this system with an object oriented programming course taken by students in our university. [ABSTRACT FROM AUTHOR]

The major bottlenecks in expert system development lie within the processes of eliciting and representing knowledge. Knowledge representation schemes combine data structures, and interpretative procedures that enable the extraction of the knowledge embedded in the data structures. A broad spectrum of knowledge types need to be represented, but available representation techniques are not optimum systems since they vary in level of expressiveness and power. Knowledge demands more than the conventional representation structures used for databases and information. This is because information is derived from processing, refining and analysing raw data. The extra refinement, analysis and addition of heuristics to information converts it to knowledge. This paper discusses the major issues in the quest for an efficient knowledge representation technique and assesses the performance and level of usefulness of some of the most successful approaches in knowledge representation. [ABSTRACT FROM AUTHOR]

Pandora is a tool for supporting the learning of first order natural deduction. It includes a help window, an interactive context sensitive tutorial known as the “e-tutor” and facilities to save, reload and export to LATEX. Every attempt to apply a natural deduction rule is met with either success or a helpful error message, providing the student with instant feedback. Detailed electronic logs of student usage are recorded for evaluation purposes. This paper describes the basic functionality, the e-tutor, our experiences of using the tool in teaching and our future plans. [ABSTRACT FROM PUBLISHER]

We would like to introduce the web tutor ORGANON, which aims to support basic logic courses at the University of West Bohemia in Pilsen (Czech Republic). The application was designed to fulfill two requirements. Firstly, it should help students during their study to practice exercises on their own (providing permanent control during students’ practicing exercises as well as answering students’ questions immediately as they arise). Secondly, it should reduce teachers’ burden (diminishing the amount of consultations as well as administrating students’ homework including correcting and grading). The tutor is available at http://kfi.zcu.cz/lide/dostalova/organon. [ABSTRACT FROM PUBLISHER]

We study predicate logic that is interpreted in Kripke models similarly to intuitionistic logic except that the accessibility relation of each model is not necessarily reflexive. Unlike in Ruitenburg's Basic Predicate Calculus, which is previous work on logic of this kind, the notion of formula in our system is the standard one in predicate logic. We give an axiomatization for this logic in the style of tree-sequent calculus (a special form of labelled sequent calculus) and prove its completeness with respect to the class of Kripke models. [ABSTRACT FROM PUBLISHER]

This paper presents a visual framework for modelling complex legal reasoning—reasoning that integrates legal rules and policies with expert and non-expert evidence. The framework is based on a many-valued, predicate, default logic. The paper first visualizes the two sides of the rule-evidence interface: rule-based deductions and evidence evaluation. It then explores ways to visualize several dynamics around that interface, including dynamics concerning evidentiary relevance, findings of fact, process decision making about motions, policy-based reasoning about rules and relevant-factor reasoning. The paper then concludes with visualizing dynamics across multiple cases and briefly discusses one pathway by which new legal rules might emerge from the factfinding process. The paper therefore presents a visual working environment for people who litigate or decide actual cases, who study judicial or administrative reasoning or who teach law. [ABSTRACT FROM AUTHOR]

In this paper, a formal approach based on predicate logic is proposed for representing and reasoning of trusted computing models. Predicates are defined to represent the characteristics of the objects and the relationship among these objects in a trusted system according to trusted computing specifications. Inference rules of trusted relation are given too. With the semantics proposed, some trusted computing models are formalized and verified, which shows that Predicate calculus logic provides a general and effective method for modeling and reasoning trusted computing systems. [ABSTRACT FROM AUTHOR]

The article proves that predicate logic gives rise to effective implementations of the answer-set programming (ASP) paradigm. Two logics were used to represent the general constraints and relevant background knowledge of the problem based on predicate calculus. It was demonstrated that the problem can be reduced to that of computing models of prepositional theories.