Grafting Modalities onto Substructural Implication Systems

We investigate the semantics of the logical systems obtained by introducing the modalities and into the family of substructural implication logics (including relevant, linear and intuitionistic implication). Then, in the spirit of the LDS (Labelled Deductive Systems) methodology, we "import" this semantics into the classical proof system KE. This leads to the formulation of a uniform labelled refutation system for the new logics which is a natural extension of a system for substructural implication developed by the first two authors in a previous paper.     

Launching themes in Israeli fathers and mothers

This study focused on launching processes as reflected in the reactions of Israeli parents to the drafting of their eldest son. A questionnaire tapping parents' reactions was constructed and administered to 237 couples. Factor analysis delineated eight substantive factors: Emotional Investment, Parent-Child Strains, Fostering Son's Maturity, Parental Disengagement, Parent's Transitional Phase, Dissatisfaction with Army, Son's Unpreparedness, and Strengthening Family Relations. The factors depicted modes of coping with launching and transitional midlife processes. The construct validity of the factor scales was examined in a multivariate regression analysis with 12 predictor variables related to sociodemographics, attitudes, personal concerns, and satisfactions. Mothers differed from fathers in some factor scale means as well as in the pattern in which the predictor variables related to the factor scale scores. The results are interpreted in terms of ambivalent launching reactions involving distress on the one hand and a sense of growth on the other. While adaptation to this transition in the family takes place within a specific cultural context, its implications for universal launching features are also discussed.     

Systematic Selection of Job Evaluation Items

Disposer d'items pertinents pouvant servir à la comparaison des postes est de premiere importance. Pourtant la littérature ne propose pas de solutions claires pour la selection de ces items. Notre travail suggere des principes pouvant presider a leur selection et a leur elaboration. Une serie d'items d'evaluation ont été selectionries et soumis a une prevalidation. L'analyse des relations entre les items d'evaluation des taches a mis en evidence trois types de relations: lineaires, non lineaires et absence de relations. Les items en relation lineaire et ceux qui pouvaient etre observes fidelement ont été juges convenir a revaluation du travail.
Des principes complementaires de selection des items ont été tires de l'analyse de contenu: les items decrivant la realisation de la tache, le niveau de la performance, et les items suffisamment generaux et independants de postes precis ou de groupes professionnels ont été retenus. Quatre dimensions de 1'evaluation du travail ont aussi été mises en evidence (la notion de limitation de l'autonomie dans la realisation de la tache les concerne tous): (1) precision des instructions recues, (2) controle hierarchique, (3) maitrise du travail, et (4) possibility d'introduire des changements.
Sur la base des principes et des dimensions, on a defini une serie de sept items generaux de 1'evaluation du travail. Les evaluations empiriques ont corrobore l'hypothese selon laquelle une hierarchie des postes approximative-ment unidimensionnelle pouvait etre obtenue.     

Moses' “Revelation” on Mount Horeb as a near-death experience

Moses, the leader and lawgiver to the people of Israel, went through a metamorphosis during his stay in the Sinai Desert, which can be explained as a near-death or near-death-like experience. Moses saw and heard God in the burning bush and yet survived. Following his revelation, he reached a higher level of consciousness, which enabled personality changes to occur. From being a simple shepherd of his father-in-law's flock, he turned into a prophet and charismatic leader of his people.     

Labelled Resolution for Classical and Non-classical Logics

Resolution is an effective deduction procedure for classical logic. There is no similar "resolution" system for non-classical logics (though there are various automated deduction systems). The paper presents resolution systems for intuistionistic predicate logic as well as for modal and temporal logics within the framework of labelled deductive systems. Whereas in classical predicate logic resolution is applied to literals, in our system resolution is applied to L(abelled) R(epresentation) S(tructures). Proofs are discovered by a refutation procedure defined on LRSs, that imposes a hierarchy on clause sets of such structures together with an inheritance discipline. This is a form of Theory Resolution. For intuitionistic logic these structures are called I(ntuitionistic) R(epresentation) S(tructures). Their hierarchical structure allows the restriction of unification of individual variables and/or constants without using Skolem functions. This structures must therefore be preserved when we consider other (non-modal) logics. Variations between different logics are captured by fine tuning of the inheritance properties of the hierarchy. For modal and temporal logics IRS's are extended to structures that represent worlds and/or times. This enables us to consider all kinds of combined logics.     

Fibred Security Language

We study access control policies based on the says operator by introducing a logical framework called Fibred Security Language (FSL) which is able to deal with features like joint responsibility between sets of principals and to identify them by means of first-order formulas. FSL is based on a multimodal logic methodology. We first discuss the main contributions from the expressiveness point of view, we give semantics for the language both for classical and intuitionistic fragment), we then prove that in order to express well-known properties like ‘speaks-for’ or ‘hand-off’, defined in terms of says, we do not need second-order logic (unlike previous approaches) but a decidable fragment of first-order logic suffices. We propose a model-driven study of the says axiomatization by constraining the Kripke models in order to respect desirable security properties, we study how existing access control logics can be translated into FSL and we give completeness for the logic.     

Modal Provability Foundations for Argumentation Networks

Given an argumentation network we associate with it a modal formula representing the ‘logical content’ of the network. We show a one-to-one correspondence between all possible complete Caminada labellings of the network and all possible models of the formula.     

Abductive reasoning in neural-symbolic systems

Abduction is or subsumes a process of inference. It entertains possible hypotheses and it chooses hypotheses for further scrutiny. There is a large literature on various aspects of non-symbolic, subconscious abduction. There is also a very active research community working on the symbolic (logical) characterisation of abduction, which typically treats it as a form of hypothetico-deductive reasoning. In this paper we start to bridge the gap between the symbolic and sub-symbolic approaches to abduction. We are interested in benefiting from developments made by each community. In particular, we are interested in the ability of non-symbolic systems (neural networks) to learn from experience using efficient algorithms and to perform massively parallel computations of alternative abductive explanations. At the same time, we would like to benefit from the rigour and semantic clarity of symbolic logic. We present two approaches to dealing with abduction in neural networks. One of them uses Connectionist Modal Logic and a translation of Horn clauses into modal clauses to come up with a neural network ensemble that computes abductive explanations in a top-down fashion. The other combines neural-symbolic systems and abductive logic programming and proposes a neural architecture which performs a more systematic, bottom-up computation of alternative abductive explanations. Both approaches employ standard neural network architectures which are already known to be highly effective in practical learning applications. Differently from previous work in the area, our aim is to promote the integration of reasoning and learning in a way that the neural network provides the machinery for cognitive computation, inductive learning and hypothetical reasoning, while logic provides the rigour and explanation capability to the systems, facilitating the interaction with the outside world. Although it is left as future work to determine whether the structure of one of the proposed approaches is more amenable to learning than the other, we hope to have contributed to the development of the area by approaching it from the perspective of symbolic and sub-symbolic integration.

Effects of energy availability on immediate and delayed emotional reactions to work events

This study focuses on daily work events as proximal stimuli for discrete emotional reactions and suggests that availability of energy resources required for coping with goal-disruptive events, or for capitalizing on new opportunities offered by goal-enhancing events, influences intensity of emotional reactions. Using experience-sampling methodology with a sample of hospital residents, it is shown that negative emotion and fatigue following disruptive events are intensified when only limited energy resources are available due to current workload. However, positive emotions, promoted by goal-enhancing events, are mitigated due to inability to capitalize on new opportunities or challenges. Aftereffects of work events reveal that the energizing effect of goal-enhancing events mitigates end-of-day fatigue and negative emotion on high-workload days, although the effect of disruptive events is diminished by the end of such days, apparently because of lesser conspicuity against a background of high workload. Theoretical and practical implications are discussed.