Z Logic and its Consequences

This paper provides an introduction to the specification language Z from a logical perspective. The possibility of presenting Z in this way is a consequence of a number of joint publications on Z logic that Henson and Reeves have co-written since 1997. We provide an informal as well as formal introduction to Z logic and show how it may be used, and extended, to investigate issues such as equational logic, the logic of preconditions, the issue of monotonicity and both operation and data refinement

Logiki mediów a dziennikarstwo informacyjne

Logiki współczesnych mediów rozumiane jako różne zestawy reguł ich funkcjonowania przekładają się na praktyki dziennikarskie oraz odgrywają fundamentalną rolę w procesach produkcji wiedzy medialnej . Efekty logik mediów masowych, nowych i społecznościowych mają zatem doniosłe znaczenie nie tylko dla dziennikarstwa, lecz dla całej mentalnej infosfery. Aby scharakteryzować te logik w kontekście dziennikarstwa informacyjnego proponujemy artykuł przeglądowy z elementami wkładu teoretycznego. Ze względu na presję, jaką logiki mediów wywierają na współczesne praktyki dziennikarskie przyjmujemy perspektywę krytyczną. W podejście medioznawcze wplatamy tło filozoficzne, odwołując się do epistemologii społecznej i etyki. Pozwala to na poszerzenie perspektywy, z której patrzymy na współczesne dziennikarstwo informacyjne. Nasze wnioski obejmują trzy główne ustalenia: pojęcia mediatyzacji i logiki mediów w pewnym sensie wzajemnie się wspierają i uzupełniają; istnieje swoista luka konceptualna między logiką mediów masowych a logiką mediów społecznościowych (new media logic); zasady logiki mediów wdzierają się do infosfery, powodując przesunięcie epistemologiczne.Media logics and news journalismAbstract: The logics of modern media, understood as different sets of rules for their functioning, not only translate into journalistic practises but also play a fundamental role in the processes of media knowledge production. Depending on the type of media, logic: mass media, new media or social media, the consequences of its application for the mental infosphere may vary. To characterise the logics of contemporary media in the context of news journalism, we offer a review article with elements of theoretical contribution. Because of the pressures that media logics put on contemporary journalistic practises, we take a critical perspective. We weave a philosophical background into the media studies approach, referring to social epistemology and ethics. This allows us to broaden the perspective from which we look at contemporary news journalism. Our conclusions encompass three main findings: the concepts of mediatization and media logic are mutually supportive and complementary in a sense; there is a kind of conceptual gap between the logic of mass media and the logic of social media (new media logic); the principles of media logics invade the infosphere, causing an epistemological shift

Anytime Computation of Cautious Consequences in Answer Set Programming

Query answering in Answer Set Programming (ASP) is usually solved by computing (a subset of) the cautious consequences of a logic program. This task is computationally very hard, and there are programs for which computing cautious consequences is not viable in reasonable time. However, current ASP solvers produce the (whole) set of cautious consequences only at the end of their computation. This paper reports on strategies for computing cautious consequences, also introducing anytime algorithms able to produce sound answers during the computation.Comment: To appear in Theory and Practice of Logic Programmin

Nonmonotonic Probabilistic Logics between Model-Theoretic Probabilistic Logic and Probabilistic Logic under Coherence

Recently, it has been shown that probabilistic entailment under coherence is weaker than model-theoretic probabilistic entailment. Moreover, probabilistic entailment under coherence is a generalization of default entailment in System P. In this paper, we continue this line of research by presenting probabilistic generalizations of more sophisticated notions of classical default entailment that lie between model-theoretic probabilistic entailment and probabilistic entailment under coherence. That is, the new formalisms properly generalize their counterparts in classical default reasoning, they are weaker than model-theoretic probabilistic entailment, and they are stronger than probabilistic entailment under coherence. The new formalisms are useful especially for handling probabilistic inconsistencies related to conditioning on zero events. They can also be applied for probabilistic belief revision. More generally, in the same spirit as a similar previous paper, this paper sheds light on exciting new formalisms for probabilistic reasoning beyond the well-known standard ones.Comment: 10 pages; in Proceedings of the 9th International Workshop on Non-Monotonic Reasoning (NMR-2002), Special Session on Uncertainty Frameworks in Nonmonotonic Reasoning, pages 265-274, Toulouse, France, April 200

Semilattices global valuations in the topos approach to quantum mechanics

In the framework of the topos approach to quantum mechanics a kind of global valuation is introduced and studied. It allows us to represent certain features related to the logical consequences of properties about quantum systems when its phase space is endowed with an intuitionistic structureFil: Freytes Solari, Hector Carlos. Università di Cagliari; Italia. Universidad Nacional de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: de Ronde, Christian. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Filosofía "Dr. Alejandro Korn"; Argentina. Center Leo Apostel; Bélgica. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Domenech, Graciela. Center Leo Apostel; Bélgica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Principles and Implementation of Deductive Parsing

We present a system for generating parsers based directly on the metaphor of parsing as deduction. Parsing algorithms can be represented directly as deduction systems, and a single deduction engine can interpret such deduction systems so as to implement the corresponding parser. The method generalizes easily to parsers for augmented phrase structure formalisms, such as definite-clause grammars and other logic grammar formalisms, and has been used for rapid prototyping of parsing algorithms for a variety of formalisms including variants of tree-adjoining grammars, categorial grammars, and lexicalized context-free grammars.Comment: 69 pages, includes full Prolog cod

Dependence Logic with Generalized Quantifiers: Axiomatizations

We prove two completeness results, one for the extension of dependence logic by a monotone generalized quantifier Q with weak interpretation, weak in the meaning that the interpretation of Q varies with the structures. The second result considers the extension of dependence logic where Q is interpreted as "there exists uncountable many." Both of the axiomatizations are shown to be sound and complete for FO(Q) consequences.Comment: 17 page