Modal tableaux for nonmonotonic reasoning

The tableau-like proof system KEM has been proven to be able to cope with a wide variety of (normal) modal logics. KEM is based on D'Agostino and Mondadori's (1994) classical proof system KE, a combination of tableau and natural deduction inference rules which allows for a restricted ("analytic") Use of the cut rule. The key feature of KEM, besides its being based neither on resolution nor on standard sequent/tableau inference techniques, is that it generates models and checks them using a label scheme to bookkeep "world" paths. This formalism can be extended to handle various system of multimodal logic devised for dealing with nonmonotonic reasoning, by relying in particular on Meyer and van der Hoek's (1992) logic for actuality and preference. In this paper we shall be concerned with developing a similar extension this time by relying on Schwind and Siegel's (1993,1994) system H, another multimodal logic devised for dealing with nonmonotonic inference

KED: a deontic theorem prover

Deontic logic (DL) is increasingly recognized as an indispensable tool in such application areas as formal representation of legal knowledge and reasoning, formal specification of computer systems and formal analysis of database integrity constraints. Despite this acknowledgement, there have been few attempts to provide computationally tractable inference mechanisms for DL. In this paper we shall be concerned with providing a computationally oriented proof method for standard DL (SDL), i.e., normal systems of modal logic with the usual possible-worlds semantics. Because of the natural and easily implementable style of proof construction it uses, this method seems particularly well-suited for applications in the AI and Law field, and though in the present version it works for SDL only, it forms an appropriate basis for developing efficient proof methods for more expressive and sophisticated extensions of SDL

A modal computational framework for default reasoning

Usually a default rule A : B/C is intended to mean that if A holds in a state of affairs a B is consistent, then C follows by default. However, C is not a necessary conclusion: different states of affairs are possible (conceivable). According to this view, Meyer and van der Hoek developed a multimodal logic, called S5P(n), for treating non-monotonic reasoning in a monotonic setting. In this paper we shall describe a proof search algorithm for S5P(n) which has been implemented as a Prolog Interpreter

Implementasi Metode Granada dalam Penerjemahan Al- Qur’an (Studi di Panti Asuhan Putra Mulia Jakarta Timur)

Granada method as one method of translating the Qur'an that exists in the community has an important role in improving human resources (HR). Granada methods not only provide knowledge and technical skills but far more important to inculcate moral values and their application in every day, because once they understand the methods of Granada will be able to understand the meaning of the verses they read. The study of this thesis formulates three main issues as follows: 1). How is the implementation of Granada in the learning method of translation of the Qur'an. 2). How cans the effectiveness of Granada in the learning method of translation of the Qur'an. 3). What factors that support and hinder the implementation of the method of Granada. The purpose of this study is: 1). To know the implementation of Granada in the learning method of translation of the Qur'an. 2). Methods To determine the effectiveness of Granada in learning the Quran translator 3). To find the supporting factors and obstacles in the implementation of Granada method in studying the translator of the Qur'an. The research methods used in the preparation of this paper is to use Qualitative Methods Naturalistic, a method that produces descriptive data. The data obtained from the manuscripts, interviews, field notes, photographs, tape recorders, and other official documents. As for things that support the implementation of Granada method is: First, teachers who oversee the learning process are the ones who truly understand the Arabic language. Because the teachers are recruited from graduates of Granada Method LIPIA (Indonesian Institute of Education Sciences Arabia) and graduate school and alumni of the training method of Granada. Second, participants assisted with the module and VCD tutorial that summarizes all the material that will be studied. Third, the method is very short and compact so it does not beat around the bush so it takes a long time. Fourth, the spirit wants to know who so profoundly from the participants. And the Fifth, the delivery of a varied pattern. In general, obstacles often faced by the participants is difficult to adapt to this method at the beginning of the meeting, especially for those who have never previously knew Arabic, and at the time of writing memorized study abroad (dictation

Evaluation von Wissensrepräsentationssystemen

Ziel dieses Berichtes ist eine Evaluation von aktuellen Wissensrepräsentationssystemen, insbesondere terminologischen Logiken. Nach Aufstellung der relevanten Evaluationskriterien erfolgt zunächst eine allgemeine Behandlung von KL-ONE - der Urmutter der terminologischen Logiken -, wobei schon einige inhärente kritische Punkte der zu behandelnden Systeme aufgezeigt werden. Anschließend werden Syntax- und Semantikdefinitionen von KL-ONE-Derivaten vorgestellt, um deren Sprachumfang zu vergleichen. Neben den gängigen KL-ONE-Derivaten wird auch die in LILOG verwendete Repräsentationssprache vorgestellt. Abschließend erfolgt ein zusammenfassender Vergleich der Systeme. Hierbei stellt sich heraus, dass insbesondere die Systeme LOOM, CLASSIC, KRIS und BACK bezüglich des verwendeten Sprachumfangs und der Effizienz der Inferenzen gut abschneiden. Die Systeme BACK und KRIS sind dabei für Verbmobil besonders relevant, da sie relativ leicht verfügbar sind. Außerdem zeichnet sich BACK durch ein gut strukturiertes Handbuch aus und eine schnelle neue Implementierung In C. Kritisch bei allen vorgestellten Systemen ist die Darstellung zeitlicher Zusammenhänge (Ereignisse, Aktionen); hierzu liegen jedoch schon Forschungsergebnisse für die Erweiterung der terminologischen Sprachen vor

Towards a unified theory of intensional logic programming

AbstractIntensional Logic Programming is a new form of logic programming based on intensional logic and possible worlds semantics. Intensional logic allows us to use logic programming to specify nonterminating computations and to capture the dynamic aspects of certain problems in a natural and problem-oriented style. The meanings of formulas of an intensional first-order language are given according to intensional interpretations and to elements of a set of possible worlds. Neighborhood semantics is employed as an abstract formulation of the denotations of intensional operators. Then we investigate general properties of intensional operators such as universality, monotonicity, finitariness and conjunctivity. These properties are used as constraints on intensional logic programming systems. The model-theoretic and fixpoint semantics of intensional logic programs are developed in terms of least (minimum) intensional Herbrand models. We show in particular that our results apply to a number of intensional logic programming languages such as Chronolog proposed by Wadge and Templog by Abadi and Manna. We consider some elementary extensions to the theory and show that intensional logic program clauses can be used to define new intensional operators. Intensional logic programs with intensional operator definitions are regarded as metatheories

An automated approach to normative reasoning

Deontic logic (DL) is increasingly recognized as an indispensable tool in such application areas as formal representation of legal knowledge and reasoning, formal specification of computer systems and formal analysis of database integrity constraints. Despite this acknowledgement, there have been few attempts to provide computationally tractable inference mechanisms for DL. In this paper we shall be concerned with providing a computationally oriented proof method for standard DL (SDL), i.e., normal systems of modal logic with the usual possible-worlds semantics. Because of the natural and easily implementable style of proof construction it uses, this method seems particularly well-suited for applications in the AI and Law field, and though in the present version it works for SDL only, it forms an appropriate basis for developing efficient proof methods for more expressive and sophisticated extensions of SDL

A tale of two models: formal verification of KEMTLS via Tamarin

KEMTLS is a proposal for changing the TLS handshake to authenticate the handshake using long-term key encapsulation mechanism keys instead of signatures, motivated by trade-offs in the characteristics of post-quantum algorithms. Prior proofs of security of KEMTLS and its variant KEMTLS-PDK have been hand-written proofs in the reductionist model under computational assumptions. In this paper, we present computer-verified symbolic analyses of KEMTLS and KEMTLS-PDK using two distinct Tamarin models. In the first analysis, we adapt the detailed Tamarin model of TLS 1.3 by Cremers et al. (ACM CCS 2017), which closely follows the wire-format of the protocol specification, to KEMTLS(-PDK). We show that KEMTLS(-PDK) has equivalent security properties to the main handshake of TLS 1.3 proven in this model. We were able to fully automate this Tamarin proof, compared with the previous TLS 1.3 Tamarin model, which required a big manual proving effort; we also uncovered some inconsistencies in the previous model. In the second analysis, we present a novel Tamarin model of KEMTLS(-PDK), which closely follows the multi-stage key exchange security model from prior pen-and-paper proofs of KEMTLS(-PDK). The second approach is further away from the wire-format of the protocol specification but captures more subtleties in security definitions, like deniability and different levels of forward secrecy; it also identifies some flaws in the security claims from the pen-and-paper proofs. Our positive security results increase the confidence in the design of KEMTLS(-PDK). Moreover, viewing these models side-by-side allows us to comment on the trade-off in symbolic analysis between detail in protocol specification and granularity of security properties