Logics in Artificial Intelligence: 17th European Conference, JELIA 2021, Virtual Event, May 17–20, 2021, Proceedings

Preface
Organization
Contents
Argumentation
Graph-Classes of Argumentation Frameworks with Collective Attacks
	1 Introduction
	2 Preliminaries
		2.1 Argumentation Frameworks
		2.2 Complexity
	3 Graph Classes
		3.1 Acyclicity
		3.2 Symmetry
		3.3 Bipartiteness
		3.4 Tractable Fragments
	4 Conclusion
	References
Introducing a Tool for Concurrent Argumentation
	1 Preliminaries
	2 Implementation
		2.1 Web Interface
	3 Conclusion and Future Work
	References
Probabilistic Argumentation: An Approach Based on Conditional Probability –A Preliminary Report–
	1 Introduction
	2 Logic and Probability
	3 Using Conditional Probability in Arguments
	4 Future Work
	References
Belief Revision
Conditional Descriptor Revision and Its Modelling by a CSP
	1 Introduction
	2 Logical Preliminaries
	3 Descriptors and Descriptor Revision
	4 Conditional Descriptor Revision
	5 Modelling Conditional Descriptor Revision by a CSP
	6 Implementation
	7 Summary and Future Work
	References
Trust Is All You Need: From Belief Revision to Information Revision
	1 Introduction
	2 Motivation
	3 Formal Preliminaries
	4 Information Revision
	5 Relevant Change Propagation
		5.1 Joint Revision Wave
		5.2 Refutation Propagation Wave
		5.3 Confirmation Propagation Wave
	6 Conclusion and Future Work
	References
Reasoning about Actions, Causality, and Change
Computing Defeasible Meta-logic
	1 Introduction
	2 Logic
	3 Algorithms
		3.1 Computational Properties
	4 Conclusions and Related Work
	References
Syntax Splitting for Iterated Contractions, Ignorations, and Revisions on Ranking Functions Using Selection Strategies
	1 Introduction
	2 Background
	3 Contractions, Revisions, and Ignorations
	4 Syntax Splitting on Ranking Functions
	5 Selection Strategies for c-Changes
	6 Selection Strategies and Syntax Splitting
	7 Conclusion
	References
An Epistemic Logic for Multi-agent Systems with Budget and Costs
	1 Introduction
	2 Logical Framework
		2.1 Syntax
		2.2 Semantics
		2.3 Problem Specification and Inference: An Example
	3 Axiomatization and Strong Completeness
	4 Discussion and Future Work
	References
Epistemic Reasoning About Rationality and Bids in Auctions
	1 Introduction
	2 Auctions as State-Transition Models
	3 Epistemic Auction Description Language
		3.1 Syntax
		3.2 Semantics
		3.3 Running Example: Dutch Auction
	4 Rationality in Auctions
		4.1 Rationality
		4.2 Example: Rationality on the Dutch Auction
	5 Model Checking
	6 Conclusion
	References
Constraint Satisfaction
Tractable Combinations of Theories via Sampling
	1 Introduction
	2 Sampling for a Theory
	3 Sampling for Unions of Theories
	4 Exemplary Application to CSPs
	References
Analyzing Unit Read-Once Refutations in Difference Constraint Systems
	1 Introduction
	2 Statement of Problems
	3 Motivation and Related Work
	4 The UROR Refutation System
		4.1 The Feasibility Problem
		4.2 An FPT Algorithm
		4.3 An Exact Exponential Algorithm
	5 Approximability
	6 Conclusion
	References
Residuation for Soft Constraints: Lexicographic Orders and Approximation Techniques
	1 Introduction
	2 Preliminaries
		2.1 Ordered Monoids
		2.2 Residuated Monoids
	3 The Ideal of Collapsing Elements
		3.1 A Different View on Collapsing Elements
	4 On Lexicographic Orders
		4.1 On Lexicographic Residuation
		4.2 Infinite Tuples
	5 Mini-bucket Elimination for Residuated POMs
		5.1 Soft Branch-and-Bound
	6 Conclusions and Future Works
	References
Description Logics and Ontological Reasoning
Exploiting Forwardness: Satisfiability and Query-Entailment in Forward Guarded Fragment
	1 Introduction
		1.1 Our Motivation and Related Work
		1.2 Our Results
	2 Preliminaries
		2.1 Queries
	3 Forward Guarded Fragment
		3.1 Logics
		3.2 Simplified Forms and Forward Types
		3.3 Higher-Arity-Forest-(Counter)Model Property
		3.4 ExpTime-Completeness of the kb Satisfiability Problem
	4 Query Answering
		4.1 Rolling-Up: Detecting Matches of Tree-Shaped Queries
		4.2 Fork Rewritings: Describing Different Collapsings of a Query
		4.3 Splittings: Describing Query Matches in an Abstract Way
		4.4 Spoilers: Blocking Query Matches
	5 Conclusions and Future Work
	References
An Algebraic View on p-Admissible Concrete Domains for Lightweight Description Logics
	1 Introduction
	2 Preliminaries
	3 Integrating p-Admissible Concrete Domains into EL
	4 Algebraic Characterizations of Convexity
	5 Examples of Convex and p-Admissible Structures
		5.1 Convex -Categorical Structures
		5.2 Convex Structures with Forbidden Patterns
		5.3 Convex Numerical Structures
	6 -Admissibility versus p-Admissibility
	7 Conclusion
	References
ReAD: AD-Based Modular Ontology Classification
	1 Introduction
	2 Background and Related Work
	3 Theoretical Foundations
	4 AD-Based Classification with Delegate Reasoners
		4.1 An AD-Based Classification Algorithm
	5 Implementation and Evaluation
		5.1 Experimental Setting
		5.2 EL++-Part and Modules
		5.3 Classification Time and Number of STs Carried Out
	6 Conclusion
	References
Weighted Defeasible Knowledge Bases and a Multipreference Semantics for a Deep Neural Network Model
	1 Introduction
	2 The Description Logics ALC and EL
	3 Fuzzy Description Logics
	4 A Concept-Wise Multipreference Semantics for Weighted KBs
		4.1 Weighted EL Knowledge Bases
		4.2 The Concept-Wise Preferences from Weighted Knowledge Bases
		4.3 A Semantics Closure Construction for Weighted Knowledge Bases
	5 Weighted Tboxes and Multipreference Fuzzy Interpretations
	6 Preferential and Fuzzy Interpretations of Multilayer Perceptrons
		6.1 A Multipreference Interpretation of Multilayer Perceptrons
		6.2 A Fuzzy Interpretation of Multilayer Perceptrons
		6.3 Multilayer Perceptrons as Conditional Knowledge Bases
	7 Conclusions
	References
Non-classical Logics
A Computationally Grounded Logic of Graded Belief
	1 Introduction
	2 Graded Doxastic Language
	3 Belief Base Semantics
	4 Social Influence
	5 Axiomatics and Decidability
	6 Conditional Belief Operators
	7 Model Checking
	8 Epistemic Explanation
	9 Conclusion
	References
Tractability Frontiers in Probabilistic Team Semantics and Existential Second-Order Logic over the Reals
	1 Introduction
	2 Existential Second-Order Logics on R-Structures
	3 Data Complexity of Additive ESOR
		3.1 A Tractable Fragment
		3.2 Full Additive ESOR
	4 Probabilistic Team Semantics and Additive ESOR
		4.1 Probabilistic Team Semantics
		4.2 Expressivity of Probabilistic Inclusion Logic
		4.3 From Probabilistic Team Semantics to Existential Second-Order Logic
		4.4 From Existential Second-Order Logic to Probabilistic Team Semantics
	5 Interpreting Inclusion Logic in Probabilistic Team Semantics
	6 Conclusion
	References
An Epistemic Probabilistic Logic with Conditional Probabilities
	1 Introduction
	2 Syntax and Semantics
	3 Axiomatization
	4 Completeness
	5 Decidability of CKL
	6 Conclusion
	References
Logic Programming and Answer Set Programming
On Syntactic Forgetting Under Uniform Equivalence
	1 Introduction
	2 Preliminaries
	3 Uniform Forgetting from Stratified Programs
	4 Uniform Forgetting in General
	5 Conclusions
	References
Solving a Multi-resource Partial-Ordering Flexible Variant of the Job-Shop Scheduling Problem with Hybrid ASP
	1 Introduction
	2 Preliminaries
	3 Problem Formalization
		3.1 MPF-JSS Definition
		3.2 Modeling MPF-JSS with Hybrid ASP
	4 Experimental Evaluation
	5 Conclusions
	References
Tractable Reasoning Using Logic Programs with Intensional Concepts
	1 Introduction
	2 Intensional Logic Programs
	3 Three-Valued Semantics
	4 Alternating Fixpoint
	5 Computational Complexity
	6 Related Work
	7 Conclusions
	References
Estimating Grounding Sizes of Logic Programs Under Answer Set Semantics
	1 Introduction
	2 Preliminaries
	3 System predictor
	4 Experimental Analysis
	5 Conclusions
	References
Testing in ASP: Revisited Language and Programming Environment
	1 Introduction
	2 Preliminaries on Answer Set Programming
	3 Unit Testing of Answer Set Programs
	4 The ASP-WIDE Environment
	5 Related Work
	6 Conclusion
	References
An Abstract View on Optimizations in SAT and ASP
	1 Introduction
	2 Review: Abstract Logics and Modular Systems
	3 Weighted Abstract Modular Systems
	4 Formal Properties of W-Systems
	5 Conclusions
	References
Model Reconciliation in Logic Programs
	1 Introduction
	2 Background: Answer Set Programming
	3 Model Reconciliation in Logic Programs
		3.1 Computing Solutions of MRLP Problems Using ASP
	4 Characterizing Solutions
		4.1 Cost-Based Characterization
		4.2 Assertiveness Characterization
	5 Related Work and Discussions
	6 Conclusions and Future Work
	References
Lazy Stream Manipulation in Prolog via Backtracking: The Case of 2P-Kt
	1 Introduction
	2 Logic Solvers as Streams Prosumers
		2.1 Logic Solvers as Stream Producers
		2.2 Logic Solvers as Stream Consumers
		2.3 Solvers vs. the World
		2.4 Example: TSP in Prolog
	3 Solvers as Streams Prosumers via State Machine
	4 Backatrackable Predicates as Streams in 2P-Kt
		4.1 2P-Kt Solvers and Generators API
		4.2 Travelling Salesman Problem in 2P-Kt
	5 Conclusion and Future Work
	References
Transforming Gringo Rules into Formulas in a Natural Way
	1 Introduction
	2 Regular Rules
	3 F-Terms and Formulas
	4 Natural Translation, Part 1
	5 Natural Translation, Part 2
	6 Review: Definition of *
	7 Proof of the Theorem
	8 Discussion
	References
DualGrounder: Lazy Instantiation via Clingo Multi-shot Framework
	1 Introduction
	2 Preliminaries
	3 System DG
	4 Experimental Evaluation
	References
A Multi-shot ASP Encoding for the Aircraft Routing and Maintenance Planning Problem
	1 Introduction
	2 Background
		2.1 Aircraft Routing and Maintenance Planning
		2.2 Answer Set Programming
	3 Instance Generator
		3.1 Parametric Generation
		3.2 Maintenance Allocation
		3.3 Solution Cost
		3.4 Solution Viewer
	4 ASP-Based Aircraft Routing and Maintenance Planning
		4.1 Problem Encoding
		4.2 Basic Multi-shot Solving Approach
		4.3 Early-Stop Multi-shot Solving Approach
		4.4 Weighted Sum vs Level Cost Function
		4.5 Parallel Solving
	5 Conclusion
	References
Author Index