Inconsistency Handling in Prioritized Databases with Universal Constraints: Complexity Analysis and Links with Active Integrity Constraints

This paper revisits the problem of repairing and querying inconsistent databases equipped with universal constraints. We adopt symmetric difference repairs, in which both deletions and additions of facts can be used to restore consistency, and suppose that preferred repair actions are specified via a binary priority relation over (negated) facts. Our first contribution is to show how existing notions of optimal repairs, defined for simpler denial constraints and repairs solely based on fact deletion, can be suitably extended to our richer setting. We next study the computational properties of the resulting repair notions, in particular, the data complexity of repair checking and inconsistency-tolerant query answering. Finally, we clarify the relationship between optimal repairs of prioritized databases and repair notions introduced in the framework of active integrity constraints. In particular, we show that Pareto-optimal repairs in our setting correspond to founded, grounded and justified repairs w.r.t. the active integrity constraints obtained by translating the prioritized database. Our study also yields useful insights into the behavior of active integrity constraints.Comment: This is an extended version of a paper appearing at the 20th International Conference on Principles of Knowledge Representation and Reasoning (KR 2023). 28 page

Querying and Repairing Inconsistent Prioritized Knowledge Bases: Complexity Analysis and Links with Abstract Argumentation

In this paper, we explore the issue of inconsistency handling over prioritized knowledge bases (KBs), which consist of an ontology, a set of facts, and a priority relation between conflicting facts. In the database setting, a closely related scenario has been studied and led to the definition of three different notions of optimal repairs (global, Pareto, and completion) of a prioritized inconsistent database. After transferring the notions of globally-, Pareto- and completion-optimal repairs to our setting, we study the data complexity of the core reasoning tasks: query entailment under inconsistency-tolerant semantics based upon optimal repairs, existence of a unique optimal repair, and enumeration of all optimal repairs. Our results provide a nearly complete picture of the data complexity of these tasks for ontologies formulated in common DL-Lite dialects. The second contribution of our work is to clarify the relationship between optimal repairs and different notions of extensions for (set-based) argumentation frameworks. Among our results, we show that Pareto-optimal repairs correspond precisely to stable extensions (and often also to preferred extensions), and we propose a novel semantics for prioritized KBs which is inspired by grounded extensions and enjoys favourable computational properties. Our study also yields some results of independent interest concerning preference-based argumentation frameworks.Comment: 27 pages. To appear in the 17th International Conference on Principles of Knowledge Representation and Reasoning (KR 2020) without the appendi

Temporal Query Answering in DL-Lite over Inconsistent Data

In ontology-based systems that process data stemming from different sources and that is received over time, as in context-aware systems, reasoning needs to cope with the temporal dimension and should be resilient against inconsistencies in the data. Motivated by such settings, this paper addresses the problem of handling inconsistent data in a temporal version of ontology-based query answering. We consider a recently proposed temporal query language that combines conjunctive queries with operators of propositional linear temporal logic and extend to this setting three inconsistency-tolerant semantics that have been introduced for querying inconsistent description logic knowledge bases. We investigate their complexity for DL-LiteR temporal knowledge bases, and furthermore complete the picture for the consistent case

Semiring Provenance for Lightweight Description Logics

We investigate semiring provenance--a successful framework originally defined in the relational database setting--for description logics. In this context, the ontology axioms are annotated with elements of a commutative semiring and these annotations are propagated to the ontology consequences in a way that reflects how they are derived. We define a provenance semantics for a language that encompasses several lightweight description logics and show its relationships with semantics that have been defined for ontologies annotated with a specific kind of annotation (such as fuzzy degrees). We show that under some restrictions on the semiring, the semantics satisfies desirable properties (such as extending the semiring provenance defined for databases). We then focus on the well-known why-provenance, which allows to compute the semiring provenance for every additively and multiplicatively idempotent commutative semiring, and for which we study the complexity of problems related to the provenance of an axiom or a conjunctive query answer. Finally, we consider two more restricted cases which correspond to the so-called positive Boolean provenance and lineage in the database setting. For these cases, we exhibit relationships with well-known notions related to explanations in description logics and complete our complexity analysis. As a side contribution, we provide conditions on an ELHI_bot ontology that guarantee tractable reasoning.Comment: Paper currently under review. 102 page

[Report on the research visit to Geneva in the framework of the Regard grant]

Rapport de séjour de recherche à l'Institut d'histoire de la Réformation (sept.-oct. 2020) de l'Université de Genève dans le cadre de la bourse Regard. Publié dans le Bulletin de l’Institut d’histoire de la Réformation, vol. 42 (2020-2021), p. 21-22.Report on a research stay at the Institute for the History of the Reformation (Sept.-Oct. 2020) of the University of Geneva within the framework of the Regard scholarship. Published in Bulletin de l’Institut d’histoire de la Réformation, vol. 42 (2020-2021), p. 21-22.Changer la lumière en ténèbres. Martyre et anti-martyre dans l’œuvre de Théodore de Bèze (ca 1544-1603

Expelling heresy, building orthodoxy according to Théodore de Bèze (<i>De haereticis</i>, 1554)

peer reviewedEn 1553, l’exécution de Michel Servet à Genève attise la polémique sur la légitimité du pouvoir civil à punir (de mort) les hérétiques. Cette controverse offre des matériaux privilégiés à la compréhension des tensions interreligieuses du xvie siècle. Parmi ceux-ci, la présente contribution se focalise sur le traité De haereticis du théologien réformé Théodore de Bèze. Elle examinera trois niveaux discursifs – violence verbale, administration du vrai et martyrologie du diable – employés par Bèze afin de stigmatiser Servet comme déviant. Dans une approche interactionniste des rapports entre orthodoxie et hérésie, une attention particulière sera portée à la manière dont l’une se définit et s’institutionnalise en excluant l’autre.In 1553, the execution of Michael Servetus in Geneva fuelled controversy over the legitimacy of the civil authorities to punish heretics by death. This controversy offers privileged material for understanding interreligious tensions in the 16th century. Among these, the present contribution focuses on the De haereticis treatise authored by the Reformed theologian Theodore de Bèze. The paper examines three discursive levels - verbal violence, administration of the truth and martyrology of the devil - employed by Bèze to stigmatise Servetus as a deviant. In an interactionist approach to the relationship between orthodoxy and heresy, particular attention will be paid to the way in which one defines and institutionalizes itself by excluding the other.« Martyre et anti-martyre dans l’œuvre de Théodore de Bèze (ca 1543-1608)

Une rhétorique du masque. Les stratégies discursives de Bèze contre les patrones celementiae (De haereticis, 1554)

peer reviewedThis contribution focuses on Théodore de Bèze’s discursive strategies in his De haereticis (1554), written against the “apostles of tolerance” (more accurately “advocates of leniency”) such as Castellio. Bèze accuses his opponents of having cloaked their identity and true intentions in a pretence of clemency and undertakes to pull off their masks. The unveiling process, through the metaphors of devils in disguise and wolves in sheep’s clothing, threatens his enemies and prompts the reader to act against them. Bèze thus shapes a rhetoric of the mask, which consists in pointing out things as concealed to better shed light on them in line with the writer’s purposes.Cette contribution porte sur les stratégies discursives de Théodore de Bèze dans son De haereticis (1554), écrit contre les « apôtres de la tolérance » (ou, plus exactement, « avocats de la clémence ») comme Castellion. Bèze accuse ses adversaires d’avoir dissimulé leur identité et leurs intentions véritables derrière un semblant de clémence et entreprend d’ôter leur masque. Le processus de dévoilement, à travers les métaphores des diables déguisés et des loups sous l’apparence de brebis, menace ses ennemis et presse le lecteur à agir contre eux. Bèze donne ainsi forme à une rhétorique du masque, qui consiste à désigner les choses comme dissimulées afin de mieux les mettre en lumière selon les objectifs de l’auteur.« Martyre et anti-martyre dans l’œuvre de Théodore de Bèze (ca 1544-1603)

Provenance for the Description Logic ELHr

We address the problem of handling provenance information in ELHr ontologies. We consider a setting recently introduced for ontology-based data access, based on semirings and extending classical data provenance, in which ontology axioms are annotated with provenance tokens. A consequence inherits the provenance of the axioms involved in deriving it, yielding a provenance polynomial as an annotation. We analyse the semantics for the ELHr case and show that the presence of conjunctions poses various difficulties for handling provenance, some of which are mitigated by assuming multiplicative idempotency of the semiring. Under this assumption, we study three problems: ontology completion with provenance, computing the set of relevant axioms for a consequence, and query answering.Comment: This is the long version of IJCAI 2020 paper 2243 (24 pages

EMISSION X DE PLASMAS CHAUDS HORS EQUILIBRE THERMODYNAMIQUE LOCAL CREES PAR LASER

X-ray emission of mid to high Z plasmas not in local thermodynamic equilibrium (LTE) is particularly difficult to modelize due to high number of electronic transitions to take into account. Studying X-ray emission from L-shell and M-shell transitions is extremely interesting, for both benchmarking numerical calculations (especially in non LTE conditions) and understanding of non LTE atomic physic in hot and dense plasmas.Experiments have been developed with the issue of measuring as completely as possible and in independent ways the X-ray emission and the hydrodynamic evolution of the studied plasmas. These plasmas were created using high energy lasers, from solid targets, aiming to observe L-shell (bromine, niobium) or M-shell (tantalum, tungsten) emission. The experimental setup has been improved over the time, including front and rear hydrodynamic diagnostics, which allow constraining numerical simulations describing the whole plasma evolution.Then spectra were calculated by atomic physic codes, using hydrodynamic conditions determined from measurements. Measurements and simulations are in good agreement, especially for M-shell emission spectra, however calculations still lacks details to finely reproduce the observed structures, which affects mainly L-shell emission spectra.L’émission X de plasmas hors équilibre thermodynamique local (ETL) de Z moyen ou élevé est particulièrement difficile à modéliser du fait du grand nombre de transitions électroniques à prendre en compte. L’étude du rayonnement X issu des transitions de couches L et M est extrêmement intéressante, d’une part pour la validation des codes numériques (en particulier hors ETL), et d’autre part pour la compréhension de la physique atomique hors ETL dans les plasmas chauds et denses. Des expériences ont donc été développées avec pour enjeu de mesurer le plus complétement possible et de manière indépendante d’une part l’émission X, et d’autre part l’évolution hydrodynamique des plasmas étudiés. Les plasmas ont été créés à l’aide de lasers de puissance à partir de cibles solides, afin d’observer une émission de couche L (brome, niobium) ou M (tantale, tungstène). Le dispositif expérimental qui a été amélioré au cours du temps comportait plusieurs diagnostics hydrodynamiques, en face avant comme en face arrière, permettant une bonne caractérisation de l’évolution du plasma. Les mesures hydrodynamiques ainsi réalisées ont permis de contraindre des simulations numériques décrivant complètement le plasma.Des codes de physique atomique ont ensuite été utilisés pour calculer les spectres dans les conditions hydrodynamiques déterminées à partir des mesures. L'accord obtenu entre spectres expérimentaux et mesurés est bon, particulièrement pour les spectres d'émission de couche M, cependant les calculs manquent encore de détails pour reproduire finement les structures observées, ce qui affecte principalement les spectres d'émission de couche L