An Incremental Algorithm for Computing All Repairs in Inconsistent Knowledge Bases

International audienceRepair techniques are used for reasoning in presence of inconsistencies. Such techniques rely on optimisations to avoid the computation of all repairs while certain applications need the generation of all repairs. In this paper, we show that the problem of all repair computation is not trivial in practice. To account for a scalable solution, we provide an incremental approach for the computation of all repairs when the conflicts have a cardinality of at most three. We empirically study its performance on generated knowledge bases (where the knowledge base generator could be seen as a secondary contribution in itself)

Formalizing Explanatory Dialogues

International audienceMany work have proposed architectures and models to incorporate explanation within agent's design for various reasons, i.e. human-agent teamwork improvement, training in virtual environment, belief revision, to name just a few. With this novel architectures a problematic is emerged: how to communicate these explanations in a goal-directed and rule-governed dialogue system?In this paper we formalize Walton’s CE dialectical system of explanatory dialogues in the framework of Prakken. We extend this formalization within the Extended CE system by generalizing the protocol and incorporating a general account of dialectical shifts. More precisely, we show how a shift to any dialogue type can take place, as an example we describe a shift to argumentative dialogue with the goal of giving the explainee the possibility to challenge explainer's explanations. In addition, we propose the use of commitment and understanding stores to avoid circular and inconsistent explanations and to judge the success of explanation. We show that the dialogue terminates, under specific conditions, in finite steps and the space complexity of the stores evolves polynomially in the size of the explanatory model

Tuning the Hydrophilicity of Gold Nanoparticles Templated in Star-Block Copolymers

We report on a simple procedure to tune the hydrophilicity of hybrid gold nanoparticles. The nanoparticles have been prepared in the core of a poly(ethylene glycol)-block-poly( -caprolactone) (PEG-b-PCL) five-arm star block copolymer. A hydrophilic corona was then added to these hybrid gold nanoparticles by direct chemisorption of trithiocarbonate-containing poly(acrylic acid) chains. These polymers were synthesized by RAFT polymerization with a trithiocarbonate as the chain-transfer agent. The efficiency of the grafting was evidenced by TEM, AFM, and DLS and by the successful transfer of these nanoparticles from organic solvent to water

Application of sourdough in the production of fat- and salt-reduced puff pastry

Sourdough (SD), as a natural ingredient, has the highly promising potential to compensate the effect of salt reduction on flavour and the consequent influence on further sensory characteristics in bakery products. The objective of this research was to determine the impact of SD (5, 10 and 20% flour basis) on the structure, flavour and quality characteristics of puff pastry with reduced fat (-40%) and salt (-30%) content (RFRS) as well as the rheological properties of the resulting dough. A range of empirical rheological tests was carried out including dough extensibility, dough stickiness and GlutoPeak test. Subsequently, the baked puff pastry quality was investigated using a VolScan, texture analyser, C-Cell and sensory analysis. SD addition significantly changed rheological properties of the basic dough reduced in fat and salt as well as a number of major quality characteristics for the resulting puff pastry. Dough resistance decreased and dough stickiness increased (p < 0.05). Gluten formation was delayed for the higher in salt control and accelerated upon salt reduction as well as increasing levels of SD incorporation. Furthermore, SD addition weakened the gluten network. To some extent, RFRS containing SD were significantly enhanced in texture. Peak firmness of RFRS with SD was significantly decreased when compared to RFRS without SD. Furthermore, the specific volume of RFRS with 5 and 10% SD was significantly higher than for RFRS containing no SD. Finally, supported by a sensory study, the flavour and texture of reduced fat and salt pastry were distinctly improved by 10% SD addition