2023Activity reportProject-TeamBOREAL

6.1.1 InteGraal

• Name:
  InteGraal : Knowledge-Representation and Reasoning for Data Integration
• Keywords:
  Knowledge Bases, Data integration, Knowledge representation, Automated Reasoning, Heterogeneous Data, Knowledge Graphs
• Scientific Description:
  InteGraal is a tool for integrating and reasoning on heterogeneous and federated data. The tool embodies algorithms and techniques developed at the crossroads between the fields of knowledge representation and reasoning and data management. From the historic point of view, this tool is the result of a complete re-engineering of the Graal tool, whose API and functionalities have been completely updated. Also, with respect to Graal, the tool is very much oriented towards data integration.
• Functional Description:
  InteGraal has been designed in a modular way, in order to facilitate software reuse and extension. It should make it easy to test new scenarios and techniques, in particular by combining algorithms. The main features of Graal are currently the following: (1) internal storage to store data by using a SQL or RDF representation (Postgres, MySQL, HSQL, SQLite, Remote SPARQL endpoints, Local in-memory triplestores) as well as a native in-memory representation (2) data-integration capabilities for exploiting federated heterogeneous data-sources through mappings able to target systems such as SQL, RDF, and black-box (eg. Web-APIs) (3) algorithms for query-answering over heterogeneous and federated data based on query rewriting and/or forward chaining (or chase)
• Release Contributions:
  2023. Mappings for integrating heterogeneous data. Compilation-based query rewriting. Command line interface. 2022: First release, software deposit with Apache 2 licence. 2021: Functional specification, design and development of a major improved version of the tool. Started refactoring of the API, and of several modules for knowledge base representation, data storage, query answering and forward-chaining reasoning (chase). Started the development of new modules for handling heterogeneous data: mappings and federations.
• News of the Year:
  This year we added a major module including mappings for integrating heterogeneous data. We also refactored and improved compilation-based query rewriting from the previous Graal tool. We added a command line interface to interact with the platform. Moreover, the tool has been used in several internship and thesis of team, as well as for collaborations with our research partners and industrial actors.
• URL:
  https://­gitlab.­inria.­fr/­rules/­integraal
• Authors:
  Florent Tornil, Guillaume Perution-kihli, Clément Sipieter, Federico Ulliana, Jean-Francois Baget, Pierre Bisquert, David Carral Martinez, Michel Leclère, Marie-laure Mugnier
• Contact:
  Federico Ulliana

6.1.2 TreeForce

• Keywords:
  JSon, Databases, Knowledge Bases, Automated Reasoning, Rewriting, NoSQL, Data integration, Knowledge representation, Heterogeneous Data
• Functional Description:
  TreeForce is a java tool for reasoning on tree data. It leverages on query rewriting techniques and NoSQL document oriented key-value stores. This library can be seen as a general toolbox for implementing reasoning techniques tailored for tree-shaped data and rules. It is composed of two main modules. The first includes generic data structures and algorithms for trees and tree-automata. The second includes automata-based query rewriting techniques as well as efficient evaluation techniques for large sets of rewritings.
• Release Contributions:
  2023. ArangoDB wrapper. Code improvement. 2022. Novel instance-aware rewriting and evaluation algorithms. Introduced summarization, partitioning and parallelization techniques. 2021: First version of TreeForce. Automata for unordered tree languages. Automata-based query-rewriting algorithms. MongoDB wrapper.
• News of the Year:
  2023. This year, we added support for querying ArangoDB and performed several code improvements.
• Contact:
  Federico Ulliana

Existential rules.

Existential rules are first-order-logic formulas representing implications of the form $\forall X\forall Y\left[\mathrm{𝐵𝑜𝑑𝑦}(X,Y)\to \exists Z\mathrm{𝐻𝑒𝑎𝑑}(X,Z)\right]$ where Body and Head are positive conjunctions of atoms without functional symbols, and Head can have existentially quantified variables. These rules allow one to model complex relationships over the domains of interest, and at the same time dispose of a value invention mechanism through existentially quantified variables. This makes them suitable for many data and knowledge tasks on both open and closed domains. As a result, existential rules are ubiquitous in many fields. They are used to model dependencies, schema mappings, and expressive queries in databases. They are used as ontological languages as a valid complement to Description Logics, and at the same time as a generalization of so-called Horn Description Logics which lay at the foundations of important Semantic Web standards.

Rule-based query answering

Given a query $Q$, a database $D$, and a set of rules $R$, query answering asks to determine whether $D,R\vDash Q$ (where $\vDash$ denotes standard first-order logic entailment), that is if the query $Q$ is a logical consequence of the knowledge base made by the database $D$ and the rules $R$. In the field of knowledge representation and reasoning, rule-based query answering is studied for rules expressing ontologies and referred as ontology-mediated query answering (OMQA). Formalisms such as Description Logics and Existential Rules (a.k.a, Tuple-Generating-Dependencies, or Datalog$\pm$) are typically targeted for expressing ontologies. Overall, the main emphasis of this topic is in the study of rule languages and the role they play in query answering.

Rule-based query answering over heterogeneous and federated data

In this context, the problem formulation remains similar, however the database $D$ is replaced by a more complex notion of federation$(𝒟,ℳ,𝒮)$ where $𝒟$ is a collection of heterogeneous data sources, $𝒮$ is a global integration schema, and $ℳ$ is a set of mappings linking the datasources in $𝒟$ to the global schema $𝒮$. This framework is at the foundations of data integration (DI) in databases and of ontology-based data access (OBDA) in knowledge representation and reasoning. OBDA focuses on global integration schemes and rules built on ontologies enabling query rewriting, while DI is more concerned with rules representing data-dependencies. Overall, both give more emphasis to heterogeneous and federated data in rule-based query answering.

Reasoning strategies for query answering

The two prominent strategies for rule-based query answering are materialization (also known as saturation, or forward-chaining) and virtualization (also known as query rewriting, or backward chaining). Both can be seen as ways of reducing query answering (which involves reasoning) into classical query evaluation. Materialization amounts at storing the inferences enabled by rules, thereby obtaining an extended database, on which queries are evaluated. Query rewriting amounts at compiling relevant rules into the query, thereby obtaining a rewritten query (usually a union of queries), which is evaluated on the (unaltered) database. Both approaches have their own strengths, and at the basis of this duality is the fact that while materialization is independent of queries, rewriting is independent of the database. Hence, each strategy better suits certain applicative scenarios, and both can possibly be combined thereby resulting in hybrid approaches.

Contributions

This year, we studied a number of theoretical, algorithmic, and applied questions of knowledge-based data management. Our main contributions cover the following topics:

• foundational issues (Section 7.2) related to the termination of reasoning strategies using existential rules or their extension (notably with disjunctive heads);
• algorithms for querying specific data souces (Section 7.3), such as relational databases or JSON document stores provided with rules;
• the application of knowledge representation languages to modelling and reasoning on complex systems (Section 7.4).

This work led to the publications presented next.

Complementing methodological work, it is worth noting that we also pursued an important team effort in the development of tools for rule-based query answering over heterogeneous and federated such as InteGraal and TreeForce (see Section 6.1).

Chase termination

The most widespread materialization procedure for existential rules is called the chase. There are several variants of the chase which differ in terms on their computational costs and termination capabilities. The most powerful variant is the core chase which is known to terminate if and only if the knowledge base admits a finite universal model (a model that can be embedded into any other model of the knowledge base, hence is sufficient to answer unions of conjunctive queries). Other variants include the restricted (aka standard) and semi-oblivious (aka skolem) chase. These are less aggressive on the suppression of redundancies produced by materialization and may not terminate even if a finite universal model of the knowledge base exists. A ruleset that enjoys the termination of the core chase over any possible database instance, is also called a finite expansion set (FES).

Rewriting termination

First-Order (FO) rewritability is a property enjoyed by the sets of existential rules for which every input conjunctive query (CQ) admits a finite equivalent first-order-logic formula, called its rewriting. Here, equivalent is intended in the sense of query answering, and it means that whenever there is a database that (together with the rules) entails the input query, then the same database (without the rules) directly entails the rewriting. This notion coincides with that of finite unification set (FUS), which are the sets of existential rules for which breadth-first query rewriting based on piece-unifiers terminates.

7.2.1 Terminating conditions for disjunctive rules

The disjunctive skolem chase is a sound, complete, and potentially non-terminating procedure for solving Boolean conjunctive query entailment over knowledge bases of disjunctive existential rules. We develop novel acyclicity and cyclicity notions for this procedure; that is, we develop sufficient conditions to determine chase termination and non-termination. Our empirical evaluation shows that our novel notions are significantly more general than existing criteria.

• Published at AAAI Conference on Artificial Intelligence (AAAI-2023) 18 with Lukas Gerlach from TU Dresden.
• Published at Principles of Knowledge Representation and Reasoning Conference (KR-2023) 17 with Lukas Gerlach.

7.2.2 Rewriting with disjunctive existential rules and mappings

We consider the issue of answering unions of conjunctive queries (UCQs) with disjunctive existential rules and mappings. While this issue has already been well studied from a chase perspective, query rewriting within UCQs has hardly been addressed yet. We first propose a sound and complete query rewriting operator, which has the advantage of establishing a tight relationship between a chase step and a rewriting step. The associated breadth-first query rewriting algorithm outputs a minimal UCQ-rewriting when one exists. Second, we show that for any “truly disjunctive” nonrecursive rule, there exists a conjunctive query that has no UCQ-rewriting. It follows that the notion of finite unification sets (FUS), which denotes sets of existential rules such that any UCQ admits a UCQ-rewriting, seems to have little relevance in this setting. Finally, turning our attention to mappings, we show that the problem of determining whether a UCQ admits a UCQ-rewriting through disjunctive mappings is undecidable. Based on these results, we conclude with a number of open problems.

• Published at Principles of Knowledge Representation and Reasoning Conference (KR-2023) 19 and at Bases de Données Avancées (BDA-2023) 25

7.2.3 Decidability of bounded treewidth infinite core chase

The core chase, a popular algorithm for answering conjunctive queries (CQs) over existential rules, is guaranteed to terminate and compute a finite universal model whenever one exists, leading to the equivalence of the universal-model-based and the chase-based definitions of finite expansion sets (FES) – a class of rulesets featuring decidable CQ entailment. In case of non-termination, however, it is non-trivial to define a “result” of the core chase, due to its non-monotonicity. This causes complications when dealing with advanced decidability criteria based on the existence of (universal) models of finite treewidth. For these, sufficient chase-based conditions have only been established for weaker, monotonic chase variants. This paper investigates the – prima facie plausible – hypothesis that the existence of a treewidth-bounded universal model and the existence of a treewidth-bounded core-chase sequence coincide – which would conveniently entail decidable CQ entailment whenever the latter holds. Perhaps surprisingly, carefully crafted examples show that both directions of this hypothesized correspondence fail. On a positive note, we are still able to define an aggregation scheme for the infinite core chase that preserves treewidth bounds and produces a finitely universal model, i.e., one that satisfies exactly the entailed CQs. This allows us to prove that the existence of a treewidth-bounded core-chase sequence does warrant decidability of CQ entailment (yet, on other grounds than expected). Hence, for the first time, we are able to define a chase-based notion of bounded treewidth sets of rules that subsumes FES.

• Published at Principles of Database Systems Conference (PODS-2023) 1 with Sebastian Rudolph.

7.2.4 Effects of rule normalization

Most algorithms developed for existential rules rely upon some normal form that simplifies technical developments. For instance, a common assumption is that rule heads are atomic, i.e., restricted to a single atom. Such assumptions are considered to be made without loss of generality as long as all sets of rules can be normalized while preserving entailment. However, an important question is whether the properties that ensure the decidability of reasoning are preserved as well. We provide a systematic study of the impact of these procedures on the different chase variants with respect to chase (non-)termination and FO-rewritability. This also leads us to study open problems related to chase termination of independent interest.

• Published at Bases de Données Avancées (BDA-2023) 24 with Michaël Thomazo (Valda). Previously published at Principles of Knowledge Representation and Reasoning Conference (KR-2022).

7.3.1 Fine grained complexity of query answering

We studied efficient algorithms for Quantile Join Queries, abbreviated as %JQ. A %JQ asks for the answer at a specified relative position (e.g., 50% for the median) under some ordering over the answers to a Join Query (JQ). The goal is to avoid materializing the set of all join answers, and to achieve quasilinear time in the size of the database, regardless of the total number of answers. We developed a new approach to solving %JQ and showed how this approach allows not just to recover known results, but also generalize them and resolve open cases. The benefit and generality of our approach is shown by using it to establish several new complexity results. First, we prove the tractability of min and max for all acyclic JQs. Second, we extend the previous %JQ dichotomy for sum to all partial sums (over all subsets of the attributes). Third, we handle the intractable cases of sum by devising a deterministic approximation scheme that applies to every acyclic JQ.

• Published at Principle of Database Systems (PODS-2023) 22 with Nikolaos Tziavelis Wolfgang Gatterbauer, Mirek Riedewald, and Benny Kimelfeld.

Again on the fine-grained complexity of database queries, two additional works have been published this year: a conference paper at Principle of Database Systems (PODS-2023) 28 (also presented at Bases de Données Avancées (BDA-2023) and a journal paper at Transactions on Database Systems (TODS-2023) 29. These have been done by members of our team before joining Boreal.

7.3.2 Querying JSON document stores

We studied the problem of reasoning on data trees, typically encoded in JSON, which are ubiquitous in data-driven applications.This ubiquity makes urgent the development of novel techniques for querying heterogeneous JSON data in a flexible manner. We designed a rule language for JSON, called constrained tree-rules, whose purpose is to provide a high-level unified view of heterogeneous JSON data and infer implicit information. As reasoning with constrained tree-rules is undecidable, we identify a relevant subset featuring tractable query answering, for which we proposed a novel automata-based query rewriting algorithm. Furthermore, we proposed a novel approach for leveraging NoSQL document stores by means of the instance-aware query-rewriting technique, which uses summaries of data to make the rewriting process both finite and efficient. We presented an extensive experimental analysis on large collections of several million JSON records.

• Published at Proceedings of the VLDB Endowment (PVLDB-2023) 14 and Bases de Données Avancées (BDA-2023) 26.

7.4.1 Systems for reasoning on heteogeneous and federated data

We demonstrated our approach to integrating and reasoning over heterogeneous and federated data data by using our main tool: InteGraal (see Section 6). InteGraal is a highly modular tool constituted by two main components. The first is the data-integration layer which allows the users to build a federated factbase over a collection of sources. The second is the automated reasoning layer, which provides powerful means for the declarative exploitation of data through the expressive formalism of existential rules. The demonstration showcased the use of the tool in use-cases of data exploitation inspired by our collaboration with INRAE, and more precisely in the preparation of data for supporting machine learning and decision support.

• Published at Bases de Données Avancées (BDA-2023) 23.

7.4.2 Knowledge Representation formalisms for testing power plants

In the context of Mohammed Aziz Sfar Gandoura CIFRE PhD funded by EDF, we focussed on the application of a known knowledge representation formalism, namely LTL (Linear Temporal Logic), to do model checking on logical diagrams (LD). LD are a type of functional specification used for logical controllers in many nuclear power plants. The goal is to check properties on LDs and to generate counter examples serving as validation tests for logical controllers. We proposed a sound and complete LTL encoding framework for LDs allowing the use of model checking (MC) and evaluate different MC techniques on real world LD to efficiently generate counterexamples for verifiable properties.

• Published at Formal Methods for Industrial Critical Systems Conference (FMICS 2023) 20

7.4.3 Food packaging in agronomy

In collaboration with the IATE UMR at INRAE, we proposed an environmental scoring tool for food packaging based on the assessment of three key pillars of packaging sustainability: Materials, Functionality and Post-Usage fate. A participatory process involving relevant food-packaging experts and end users was applied to define the relevant criteria for each pillar. Then, the packaging options for the same food have been ranked according to the Borda voting rule, considering the individual rankings obtained for the various pillars. The proposed methodology was applied to three commercial (milk and sugar) and non-commercial (strawberry) packaging case studies. The obtained ranking has been analyzed with respect to current knowledge in the field.

• Published at Packaging Technology and Science 2023 12

7.4.4 Human-robot interactions

In collaboration with the IDH team at LIRMM, we investigated Human-Robot Interactions (HRI) in complex social settings. A robot can affect its social environment beyond the person who is interacting with it. Therefore, we examined the effect of different robot shapes in a multi-person context during dance routines, to understand how the design of the robot enhances the artistic process and through which factors human preferences are being shaped within a novel third party setting human-robot-human interaction (HRHI).

• Published at IEEE International Conference on Robot and Human Interactive Communication (RO-MAN 2023) 16

R4Agri

Participants: Pierre Bisquert, David Carral, Akira Charoensit, Marie-Laure Mugnier, Florent Tornil, Federico Ulliana.

• Title:
  “R4Agri”- Reasoning on Agricultural Data: Integrating Metrics and Qualitative Perspectives
• Partner Institution(s):
  $$

  • Inria
  • DFKI, Germany
• Date/Duration:
  42 months, started 01/01/2022
• Additional info:
  AI tools supporting competitive and sustainable agriculture need to exploit highly diverse kinds of data and knowledge, from raw data provided by sensors to high level expertise knowledge. Taking numerical agriculture as the targeted application domain, the overall goal of the R4Agri project is to provide a framework for reasoning about knowledge based on heterogeneous data, with a focus on multi-modal and multi-scale sensor data. Main challenges include context-dependent interpretation of sensor data, which involves reasoning about prior knowledge, and query answering techniques that exploit domain knowledge and accommodate the specificities of data sources in a flexible manner. The application potential in this field of world-wide societal and ecological impact will be demonstrated in realistic use cases. project.inria.fr/r4agri/

Federico Ulliana is part of the Inria CDT (Commission Développement Technologique) since May 2022. This committee is in charge of reviewing and following software development projets within the Inria centre at Université Côte d’Azur.

9.2.1 Visits of international scientists

9.2.2 Visits to international teams

CQFD (ANR PRC, Jan. 2019-Dec. 2024)

Participants: Jean-François Baget, Pierre Bisquert, Nofar Carmeli, David Carral, Michel Leclère, Marie-Laure Mugnier, Guillaume Pérution-Kihli, Olivier Rodriguez, Florent Tornil, Federico Ulliana, Antoine Amarilli [Télécom ParisTech], François Goasdoué [Institut de Recherche en Informatique et Systèmes Aléatoires - IRISA], Pierre Bourhis [SPIRALS], Ioana Manolescu [CEDAR], Michaël Thomazo [VALDA], Meghyn Bienvenu [Centre de Recherche en Informatique, Signal et Automatique de Lille - CRIStAL], Marie-Christine Rousset [Institut d'Informatique et de Mathématiques Appliquées de Grenoble - IMAG], Fabrice Jouanot [Institut d'Informatique et de Mathématiques Appliquées de Grenoble - IMAG].

CQFD (Complex ontological Queries over Federated heterogeneous Data), coordinated by Federico Ulliana (BOREAL), involves participants from Inria Saclay (CEDAR team), Inria Paris (VALDA team), Inria Nord Europe (SPIRALS team), IRISA, LIG, LTCI, and LaBRI. The aim of this project is to tackle two crucial challenges in OMQA (Ontology Mediated Query Answering), namely, heterogeneity, that is, the possibility to deal with multiple types of data-sources and database management systems, and federation, that is, the possibility of cross-querying a collection of heterogeneous datasources. By featuring 8 different partners in France, this project aims at consolidating a national community of researchers around the OMQA issue.

www.lirmm.fr/cqfd/

Convergence institute #DigitAg (2017-2026)

Participants: Jean-François Baget, Patrice Buche, Madalina Croitoru, Marie-Laure Mugnier, Federico Ulliana.

Located in Montpellier, #DigitAg (for Digital Agriculture) gathers 17 founding members: research institutes, including Inria, the University of Montpellier and higher-education institutes in agronomy, transfer structures and companies. Its objective is to support the development of digital agriculture. BOREAL is involved in this project on the issues of designing data and knowledge management systems adapted to agricultural information systems, and of developing methods for integrating different types of information and knowledge (generated from data, experts, models). A PhD thesis (Elie Najm, 2019-2022) investigated knowledge representation and reasoning for the design of new agroecological systems, in collaboration with the research laboratory ABSys - Biodiversified Agrosystems (formerly UMR SYSTEM).

www.hdigitag.fr/en/

10.1.1 Scientific events: organisation

At the LIRMM level, Madalina Croitoru is co-chair of the transversal axis and workshop on Artificial Intelligence for human-robot interaction.

10.1.2 Scientific events: selection

10.1.3 Invited talks

• Nofar Carmeli - Invited talk Accessing Answers to Conjunctive Queries with Ideal Time Guarantees - DL 2023 (36th International Workshop On Description Logics), September 2nd
• Nofar Carmeli - Invited talk Query answering: tractability beyond acyclicity - Graph and Databases workshop, Lyon, March 3rd
• Nofar Carmeli - Invited participation and talks in two workshops of the Logic and Algorithms in Database Theory and AI program at the Simons Institute, Berkeley, California
  • Accessing Answers to Unions of Conjunctive Queries with Ideal Time Guarantees at the Fine-Grained Complexity, Logic, and Query Evaluation workshop, September 25th
  • Direct Access for Conjunctive Queries with Aggregation at the Logic and Algebra for Query Evaluation workshop, November 14th

10.1.4 Scientific expertise

10.1.5 Research administration

• Madalina Croitoru has been a deputy member of the CNU section 27 (Computer Science) since September 2019.
• Madalina Croitoru was a deputy director of the Computer Science Department at the Faculty of Science, University of Montpellier from September 2021 to January 2023.
• Marie-Laure Mugnier has been president of the “Section 27 Commitee” (Computer Science) of the University of Montpellier since July 2021.
• Marie-Laure Mugnier has been a member of the Council (the Human Ressources Commission) of the Scientific Department MIPS (Mathematics Informatics Physics and Systems) of the University of Montpellier since 2016.
• Jean-François Baget represents the Boreal team at LIRMM's Computer Science Department meetings (Comité des Projets INFO) and at LIRMM's Laboratory teams meetings (CIEL) since 2021.
• Guillaume Pérution-Kihli has been a PhD student member of LIRMM's CL (Conseil de Laboratoire) and has been representing students at the doctoral school I2S.
• Guillaume Pérution-Kihli has been elected president of the PhD students council.
• Federico Ulliana is part of the Inria CDT (Commission Développement Technologique) since May 2022. This committee is in charge of reviewing and following software development projets within the Inria centre at Université Côte d’Azur.

10.2.1 Teaching

Madalina Croitoru, Michel Leclère, and Marie-Laure Mugnier, do an average of 200 teaching hours per year at the Computer Science department of the Science Faculty. They are in charge of courses in Logics (Licence), Artificial Intelligence (Master), Knowledge Representation and Reasoning (Master), Theory of Data and Knowledge Bases (Master), Social and Semantic Web (Master) and Multi-Agent Systems (Master). Concerning full-time researchers in 2023, Jean-François Baget, David Carral, and Federico Ulliana (on secondment from Montpellier University) taught in the Computer Science Master; topics include Theory of Data and Knowledge Bases, Datawarehouses, Big-Data and NoSQL systems.

Guillaume Pérution-Kihli has been coaching students from University of Montpellier for SWERC since 2020.

10.2.2 Supervision

International journals

• 12 articleJ.Julia Frojan, P.Pierre Bisquert, P.Patrice Buche, N.Nathalie Gontard, L.Lieselot Boone, T.Trang Nhu Thuy, A.An Vermeulen, P.Peter Ragaert, J.Jo Dewulf and V.Valérie Guillard. Scoring methodology for comparing the environmental performance of food packaging.Packaging Technology and Science366February 2023, 439-463HALDOIback to text
• 13 articleE.Elie Najm, M.-L.Marie-Laure Mugnier, C.Christian Gary, J.-F.Jean-François Baget, R.Raphael Métral and L.Léo Garcia. Integrating data and knowledge to support the selection of service plant species in agroecology.Computers and Electronics in Agriculture217February 2024, 108594HALDOI
• 14 articleO.Olivier Rodriguez, F.Federico Ulliana and M.-L.Marie-Laure Mugnier. Scalable Reasoning on Document Stores via Instance-Aware Query Rewriting.Proceedings of the VLDB Endowment (PVLDB)1611August 2023, 2699-2713HALDOIback to text

International peer-reviewed conferences

• 15 inproceedingsJ.-F.Jean-François Baget, M.-L.Marie-Laure Mugnier and S.Sebastian Rudolph. Bounded Treewidth and the Infinite Core Chase: Complications and Workarounds toward Decidable Querying.Proceedings of the 42nd ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database SystemsSIGMOD/PODS 2023 - International Conference on Management of DataSeattle, WA, United StatesACMJune 2023, 291-302HALDOI
• 16 inproceedingsS.-S.Sorina-Silvia Cîrcu, B.Bruno Yun, A.Abderrahmane Kheddar, C.-y.Chu-yin Chen and M.Madalina Croitoru. Dance, Dance, Dance With My Hands: Third-Party Human Robot-Human Interactions.RO-MAN 2023 - 32nd IEEE International Conference on Robot and Human Interactive Communication2023 32nd IEEE International Conference on Robot and Human Interactive Communication (RO-MAN)Busan, South KoreaIEEEAugust 2023, 1997-2002HALDOIback to text
• 17 inproceedingsL.Lukas Gerlach and D.David Carral. Do Repeat Yourself: Understanding Sufficient Conditions for Restricted Chase Non-Termination.KR 2023 - 20th International Conference on Principles of Knowledge Representation and ReasoningProceedings of the 20th International Conference on Principles of Knowledge Representation and ReasoningRhodes, GreeceInternational Joint Conferences on Artificial Intelligence OrganizationSeptember 2023, 301-310HALDOIback to text
• 18 inproceedingsL.Lukas Gerlach and D.David Carral. General Acyclicity and Cyclicity Notions for the Disjunctive Skolem Chase.AAAI-23 Technical Tracks 5AAAI 2023 - 37th Conference on Artificial Intelligence37Technical Track on Knowledge Representation and Reasoning5Washington, United StatesJune 2023, 6372-6379HALDOIback to text
• 19 inproceedingsM.Michel Leclère, M.-L.Marie-Laure Mugnier and G.Guillaume Pérution-Kihli. Query Rewriting with Disjunctive Existential Rules and Mappings.Proceedings of the 20th International Conference on Principles of Knowledge Representation and ReasoningKR 2023 - 20th International Conference on Principles of Knowledge Representation and ReasoningRhodes, GreeceInternational Joint Conferences on Artificial Intelligence Organization2023, 429-439HALDOIback to text
• 20 inproceedingsA.Aziz Sfar, D.David Carral, D.Dina Irofti and M.Madalina Croitoru. Testing Logical Diagrams in Power Plants: A Tale of LTL Model Checking.FMICS 2023 - Formal Methods for Industrial Critical Systems14290Lecture Notes in Computer ScienceAntwerp, NetherlandsSpringer Nature SwitzerlandSeptember 2023, 189-204HALDOIback to text
• 21 inproceedingsS.Shashank Shekhar, A.Anthony Favier, R.Rachid Alami and M.Madalina Croitoru. A Knowledge Rich Task Planning Framework for Human-Robot Collaboration.AI 2023 - 43rd SGAI International Conference on Artificial Intelligence14381Lecture Notes in Computer Science (LNAI)Cambridege, United KingdomDecember 2023, 259-265HALDOI
• 22 inproceedingsN.Nikolaos Tziavelis, N.Nofar Carmeli, W.Wolfgang Gatterbauer, B.Benny Kimelfeld and M.Mirek Riedewald. Efficient Computation of Quantiles over Joins.SIGMOD/PODS 2023 - International Conference on Management of DataSeattle, WA, United StatesACMJune 2023, 303-315HALDOIback to text

National peer-reviewed Conferences

• 23 inproceedingsJ.-F.Jean-François Baget, P.Pierre Bisquert, M.Michel Leclère, M.-L.Marie-Laure Mugnier, G.Guillaume Pérution-Kihli, F.Florent Tornil and F.Federico Ulliana. InteGraal: a Tool for Data-Integration and Reasoning on Heterogeneous and Federated Sources.Proceedings of the conference BDA'2023BDA 2023 - 39e Conférence sur la Gestion de Données – Principes, Technologies et ApplicationsMontpellier, FranceOctober 2023HALback to textback to text
• 24 inproceedings D.David Carral, L.Lucas Larroque, M.Michaël Thomazo and M.-L.Marie-Laure Mugnier. Normalisations of Existential Rules: Not so Innocuous! BDA 2023 - 39e Conférence sur la Gestion de Données – Principes, Technologies et Applications Montpellier, France October 2023 HAL back to text
• 25 inproceedingsM.Michel Leclère, M.-L.Marie-Laure Mugnier and G.Guillaume Pérution-Kihli. Query Rewriting with Disjunctive Existential Rules and Mappings.BDA 2023 - 39e Conférence sur la Gestion de Données - Principes, Technologies et ApplicationsMontpellier, FranceOctober 2023HALDOIback to text
• 26 inproceedingsBest paperO.Olivier Rodriguez, F.Federico Ulliana and M.-L.Marie-Laure Mugnier. Scalable Reasoning on Document Stores via Instance-Aware Query Rewriting.BDA 2023 - 39e Conférence sur la Gestion de Données – Principes, Technologies et ApplicationsMontpellier, FranceOctober 2023HALback to textback to text

Doctoral dissertations and habilitation theses

• 27 thesisG.Guillaume Pérution-Kihli. Data Management in the Existential Rule Framework: Translation of Queries and Constraints.Université de montpellierDecember 2023HALback to text