Dual Logic Concepts based on Mathematical Morphology in Stratified Institutions: Applications to Spatial Reasoning

Several logical operators are defined as dual pairs, in different types of logics. Such dual pairs of operators also occur in other algebraic theories, such as mathematical morphology. Based on this observation, this paper proposes to define, at the abstract level of institutions, a pair of abstract dual and logical operators as morphological erosion and dilation. Standard quantifiers and modalities are then derived from these two abstract logical operators. These operators are studied both on sets of states and sets of models. To cope with the lack of explicit set of states in institutions, the proposed abstract logical dual operators are defined in an extension of institutions, the stratified institutions, which take into account the notion of open sentences, the satisfaction of which is parametrized by sets of states. A hint on the potential interest of the proposed framework for spatial reasoning is also provided.Comment: 36 page

How do Public Laboratories Collaborate with Industry? New Survey Evidence from France.

This paper uses a survey of 130 public laboratories in France to investigate collaborative activities of laboratories with industry. Our statistical analysis shows that knowledge and technology development and transfer occurs most frequently through collaborative and contract research, informal exchanges, conferences, and consortia. The main benefits from the perspective of laboratories are the tangible and intangible inputs received –funds, materials, research suggestions and data. The outputs of collaboration are most often theses and publications along with technological artefacts (new products & processes, software) while patents, licenses and copyrights are less frequent. Collaboration with industry leads laboratories to conduct research in a more timely and reliable way, as well as focused in more applied areas.Economics of Science; Public-Private Research Partnerships; Knowledge and Technology Transfer; University-Industry Collaborations; France;

Belief Revision, Minimal Change and Relaxation: A General Framework based on Satisfaction Systems, and Applications to Description Logics

Belief revision of knowledge bases represented by a set of sentences in a given logic has been extensively studied but for specific logics, mainly propositional, and also recently Horn and description logics. Here, we propose to generalize this operation from a model-theoretic point of view, by defining revision in an abstract model theory known under the name of satisfaction systems. In this framework, we generalize to any satisfaction systems the characterization of the well known AGM postulates given by Katsuno and Mendelzon for propositional logic in terms of minimal change among interpretations. Moreover, we study how to define revision, satisfying the AGM postulates, from relaxation notions that have been first introduced in description logics to define dissimilarity measures between concepts, and the consequence of which is to relax the set of models of the old belief until it becomes consistent with the new pieces of knowledge. We show how the proposed general framework can be instantiated in different logics such as propositional, first-order, description and Horn logics. In particular for description logics, we introduce several concrete relaxation operators tailored for the description logic \ALC{} and its fragments \EL{} and \ELext{}, discuss their properties and provide some illustrative examples

Learning the optimal buffer-stock consumption rule of Carroll

This article questions the rather pessimistic conclusions of Allen et Carroll (2001) about the ability of consumer to learn the optimal buffer-stock based consumption rule. To this aim, we develop an agent based model where alternative learning schemes can be compared in terms of the consumption behaviour that they yield. We show that neither purely adaptive learning, nor social learning based on imitation can ensure satisfactory consumption behaviours. By contrast, if the agents can form adaptive expectations, based on an evolving individual mental model, their behaviour becomes much more interesting in terms of its regularity, and its ability to improve performance (which is as a clear manifestation of learning). Our results indicate that assumptions on bounded rationality, and on adaptive expectations are perfectly compatible with sound and realistic economic behaviour, which, in some cases, can even converge to the optimal solution. This framework may therefore be used to develop macroeconomic models with adaptive dynamics.Consumption decisions; Learning; Expectations; Adaptive behaviour; Computational economics

Quel sens de futurs enseignants attribuent-ils à l’évaluation par tâche complexe ?

L'approche par compétence développée dans le cadre de la formation professionnelle des enseignants a entraîné une modification importante des dispositifs d'évaluation. A la Haute Ecole pédagogique de Fribourg, des tâches complexes réparties sur les trois années de formation permettent de certifier le niveau d’acquisition des compétences. Après des travaux antérieurs consacrés à la question de la validité des tâches et à leur évolution analysée du point de vue des formateurs ainsi qu’à la compréhension des critères par les étudiants, cette recherche questionne les étudiants sur le sens qu’ils construisent autour de cette forme d’évaluation. Le rapport des fonctions sommative et formative au regard de l’évaluation des compétences est ainsi questionné à partir des témoignages de futurs enseignants. Cette recherche inscrite dans une visée exploratoire analyse une vingtaine d'entretiens réalisés auprès d'étudiants aborde plusieurs thématiques : la compréhension de l’évaluation réalisée par les formateurs et des différents critères, les mécanismes d'autorégulation mis en oeuvre ainsi que le sens attribué à cette forme d’évaluation. Les résultats montrent la faible compréhension des différents critères utilisés et le caractère hautement formatif associé par les étudiants à ces tâches qui ont pourtant une visée certificative. Cette communication met en évidence les liens étroits entre l’évaluation du développement de compétences professionnelles et le sens que les étudiants voient dans ce type de tâche

Compared energy efficiency of dairy cow and meat sheep farms, in organic and in conventional farming

The compared energy analysis of various farming systems makes it possible to carry out an approach of their sustainability through their faculty to produce energy in the form of livestock or vegetable products, while limiting the resort to non renewable energies. This study was carried out from the results of 38 farms in meat sheep and dairy cow production including 13 in organic farming. It focuses on livestock production, being acquired that the presence of cash crops raises considerably the energy effi-ciency. The main energy expenditure are the bought food, fertilisers and mechanization. The average en-ergy efficiency of the dairy cow farms is 0.59 and there is no difference between organic and conven-tional farming. In sheep production, the average is lower (0.41) but the organic farms have a higher level (0.47) thanks to a better food self sufficiency and no use of chemical fertilisers