ARVID BECKER, PEDRO CABALAR, MARTÍN DIÉGUEZ, TORSTEN SCHAUB, ANNA SCHUHMANN
{"title":"Metric Temporal Equilibrium Logic over Timed Traces","authors":"ARVID BECKER, PEDRO CABALAR, MARTÍN DIÉGUEZ, TORSTEN SCHAUB, ANNA SCHUHMANN","doi":"10.1017/s1471068424000139","DOIUrl":"https://doi.org/10.1017/s1471068424000139","url":null,"abstract":"In temporal extensions of answer set programming (ASP) based on linear time, the behavior of dynamic systems is captured by sequences of states. While this representation reflects their relative order, it abstracts away the specific times associated with each state. However, timing constraints are important in many applications like, for instance, when planning and scheduling go hand in hand. We address this by developing a metric extension of linear-time temporal equilibrium logic, in which temporal operators are constrained by intervals over natural numbers. The resulting Metric Equilibrium Logic (MEL) provides the foundation of an ASP-based approach for specifying qualitative and quantitative dynamic constraints. To this end, we define a translation of metric formulas into monadic first-order formulas and give a correspondence between their models in MEL and Monadic Quantified Equilibrium Logic, respectively. Interestingly, our translation provides a blue print for implementation in terms of ASP modulo difference constraints.","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"100 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142265272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-Shot Answer Set Programming for Flexible Payroll Management","authors":"BENJAMIN CALLEWAERT, JOOST VENNEKENS","doi":"10.1017/s1471068424000115","DOIUrl":"https://doi.org/10.1017/s1471068424000115","url":null,"abstract":"Payroll management is a critical business task that is subject to a large number of rules, which vary widely between companies, sectors, and countries. Moreover, the rules are often complex and change regularly. Therefore, payroll management systems must be flexible in design. In this paper, we suggest an approach based on a flexible answer set programming (ASP) model and an easy-to-read tabular representation based on the decision model and notation standard. It allows HR consultants to represent complex rules without the need for a software engineer and to ultimately design payroll systems for a variety of different scenarios. We show how the multi-shot solving capabilities of the <jats:italic>clingo</jats:italic> ASP system can be used to reach the performance that is necessary to handle real-world instances.","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"425 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140838430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GIOVANNI AMENDOLA, GIUSEPPE MAZZOTTA, FRANCESCO RICCA, TOBIAS BEREI
{"title":"Unit Testing in ASP Revisited: Language and Test-Driven Development Environment","authors":"GIOVANNI AMENDOLA, GIUSEPPE MAZZOTTA, FRANCESCO RICCA, TOBIAS BEREI","doi":"10.1017/s1471068424000103","DOIUrl":"https://doi.org/10.1017/s1471068424000103","url":null,"abstract":"<p>Unit testing frameworks are nowadays considered a best practice, included in almost all modern software development processes, to achieve rapid development of <span>correct</span> specifications. Knowledge representation and reasoning paradigms such as Answer Set Programming (ASP), that have been used in industry-level applications, are not an exception. Indeed, the first unit testing specification language for ASP was proposed in 2011 as a feature of the ASPIDE development environment. Later, a more portable unit testing language was included in the LANA annotation language. In this paper we revisit both languages and tools for unit testing in ASP. We propose a new unit test specification language that allows one to inline tests within ASP programs, and we identify the computational complexity of the tasks associated with checking the various program-correctness assertions. Test-case specifications are transparent to the traditional evaluation, but can be interpreted by a specific testing tool. Thus, we present a novel environment supporting test-driven development of ASP programs.</p>","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"203 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140569497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluating Datalog Tools for Meta-reasoning over OWL 2 QL","authors":"HAYA MAJID QURESHI, WOLFGANG FABER","doi":"10.1017/s1471068424000073","DOIUrl":"https://doi.org/10.1017/s1471068424000073","url":null,"abstract":"<p>Metamodeling is a general approach to expressing knowledge about classes and properties in an ontology. It is a desirable modeling feature in multiple applications that simplifies the extension and reuse of ontologies. Nevertheless, allowing metamodeling without restrictions is problematic for several reasons, mainly due to undecidability issues. Practical languages, therefore, forbid classes to occur as instances of other classes or treat such occurrences as semantically different objects. Specifically, meta-querying in SPARQL under the Direct Semantic Entailment Regime uses the latter approach, thereby effectively not supporting meta-queries. However, several extensions enabling different metamodeling features have been proposed over the last decade. This paper deals with the Metamodeling Semantics (MS) over OWL 2 QL and the Metamodeling Semantic Entailment Regime (MSER), as proposed in Lenzerini <span>et al</span>. (2015, <span>Description Logics</span>) and Lenzerini <span>et al</span>. (2020, <span>Information Systems 88</span>, 101294), Cima <span>et al</span>. (2017, <span>Proceedings of the 7th International Conference on Web Intelligence, Mining and Semantics</span>, 1–6). A reduction from OWL 2 QL to Datalog for meta-querying was proposed in Cima <span>et al</span>. (2017, <span>Proceedings of the 7th International Conference on Web Intelligence, Mining and Semantics</span>, 1–6). In this paper, we experiment with various logic programming tools that support Datalog querying to determine their suitability as back-ends to MSER query answering. These tools stem from different logic programming paradigms (Prolog, pure Datalog, Answer Set Programming, Hybrid Knowledge Bases). Our work shows that the Datalog approach to MSER querying is practical also for sizeable ontologies with limited resources (time and memory). This paper significantly extends Qureshi and Faber (2021, <span>International Joint Conference on Rules and Reasoning</span>, Springer, 218–233.) by a more detailed experimental analysis and more background.</p>","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"19 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140053727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Model Explanation via Support Graphs","authors":"PEDRO CABALAR, BRAIS MUÑIZ","doi":"10.1017/s1471068424000048","DOIUrl":"https://doi.org/10.1017/s1471068424000048","url":null,"abstract":"In this note, we introduce the notion of support graph to define explanations for any model of a logic program. An explanation is an acyclic support graph that, for each true atom in the model, induces a proof in terms of program rules represented by labels. A classical model may have zero, one or several explanations: when it has at least one, it is called a justified model. We prove that all stable models are justified, whereas, for disjunctive programs, some justified models may not be stable. We also provide a meta-programming encoding in Answer Set Programming that generates the explanations for a given stable model of some program. We prove that the encoding is sound and complete, that is, there is a one-to-one correspondence between each answer set of the encoding and each explanation for the original stable model.","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"36 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140009053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
JOHANNES K. FICHTE, SARAH ALICE GAGGL, MARKUS HECHER, DOMINIK RUSOVAC
{"title":"IASCAR: Incremental Answer Set Counting by Anytime Refinement","authors":"JOHANNES K. FICHTE, SARAH ALICE GAGGL, MARKUS HECHER, DOMINIK RUSOVAC","doi":"10.1017/s1471068424000036","DOIUrl":"https://doi.org/10.1017/s1471068424000036","url":null,"abstract":"Answer set programming (ASP) is a popular declarative programming paradigm with various applications. Programs can easily have many answer sets that cannot be enumerated in practice, but counting still allows quantifying solution spaces. If one counts under assumptions on literals, one obtains a tool to comprehend parts of the solution space, so-called <jats:italic>answer set navigation</jats:italic>. However, navigating through parts of the solution space requires counting many times, which is expensive in theory. <jats:italic>Knowledge compilation</jats:italic> compiles instances into representations on which counting works in polynomial time. However, these techniques exist only for conjunctive normal form (CNF) formulas, and compiling ASP programs into CNF formulas can introduce an exponential overhead. This paper introduces a technique to iteratively count answer sets under assumptions on knowledge compilations of CNFs that encode supported models. Our anytime technique uses the inclusion–exclusion principle to improve bounds by over- and undercounting systematically. In a preliminary empirical analysis, we demonstrate promising results. After compiling the input (offline phase), our approach quickly (re)counts.","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"93 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139927873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Clingraph: A System for ASP-based Visualization","authors":"SUSANA HAHN, ORKUNT SABUNCU, TORSTEN SCHAUB, TOBIAS STOLZMANN","doi":"10.1017/s147106842400005x","DOIUrl":"https://doi.org/10.1017/s147106842400005x","url":null,"abstract":"We present the Answer Set Programming (ASP)-based visualization tool <jats:italic>clingraph</jats:italic>, which aims at visualizing various concepts of ASP by means of ASP itself. This idea traces back to the <jats:italic>aspviz</jats:italic> tool and <jats:italic>clingraph</jats:italic> redevelops and extends it in the context of modern ASP systems. More precisely, <jats:italic>clingraph</jats:italic> takes graph specifications in terms of ASP facts and hands them over to the graph visualization system <jats:italic>graphviz</jats:italic>. The use of ASP provides a great interface between logic programs and/or answer sets and their visualization. Also, <jats:italic>clingraph</jats:italic> offers a Python application programming interface (API) that extends this ease of interfacing to <jats:italic>clingo</jats:italic>’s API and in turn to connect and monitor various aspects of the solving process.","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"17 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139752351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Epistemic Logic Programs: A Study of Some Properties","authors":"STEFANIA COSTANTINI, ANDREA FORMISANO","doi":"10.1017/s1471068424000012","DOIUrl":"https://doi.org/10.1017/s1471068424000012","url":null,"abstract":"<p>Epistemic logic programs (ELPs), extend answer set programming (ASP) with epistemic operators. The semantics of such programs is provided in terms of <span>world views</span>, which are sets of belief sets, that is, syntactically, sets of sets of atoms. Different semantic approaches propose different characterizations of world views. Recent work has introduced semantic properties that should be met by any semantics for ELPs, like the <span>Epistemic Splitting Property</span>, that, if satisfied, allows to modularly compute world views in a bottom-up fashion, analogously to “traditional” ASP. We analyze the possibility of changing the perspective, shifting from a bottom-up to a top-down approach to splitting. We propose a basic top-down approach, which we prove to be equivalent to the bottom-up one. We then propose an extended approach, where our new definition: (i) is provably applicable to many of the existing semantics; (ii) operates similarly to “traditional” ASP; (iii) provably coincides under any semantics with the bottom-up notion of splitting at least on the class of <span>Epistemically Stratified Programs</span> (which are, intuitively, those where the use of epistemic operators is stratified); (iv) better adheres to common ASP programming methodology.</p>","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"56 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139688961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIMON VANDEVELDE, JOOST VENNEKENS, JEROEN JORDENS, BART VAN DONINCK, MAARTEN WITTERS
{"title":"Knowledge-Based Support for Adhesive Selection: Will it Stick?","authors":"SIMON VANDEVELDE, JOOST VENNEKENS, JEROEN JORDENS, BART VAN DONINCK, MAARTEN WITTERS","doi":"10.1017/s1471068424000024","DOIUrl":"https://doi.org/10.1017/s1471068424000024","url":null,"abstract":"<p>As the popularity of adhesive joints in industry increases, so does the need for tools to support the process of selecting a suitable adhesive. While some such tools already exist, they are either too limited in scope or offer too little flexibility in use. This work presents a more advanced tool, that was developed together with a team of adhesive experts. We first extract the experts’ knowledge about this domain and formalize it in a Knowledge Base (KB). The IDP-Z3 reasoning system can then be used to derive the necessary functionality from this KB. Together with a user-friendly interactive interface, this creates an easy-to-use tool capable of assisting the adhesive experts. To validate our approach, we performed user testing in the form of qualitative interviews. The experts are very positive about the tool, stating that, among others, it will help save time and find more suitable adhesives.</p>","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"19 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139645897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Locally Tight Programs","authors":"JORGE FANDINNO, VLADIMIR LIFSCHITZ, NATHAN TEMPLE","doi":"10.1017/s147106842300039x","DOIUrl":"https://doi.org/10.1017/s147106842300039x","url":null,"abstract":"<p>Program completion is a translation from the language of logic programs into the language of first-order theories. Its original definition has been extended to programs that include integer arithmetic, accept input, and distinguish between output predicates and auxiliary predicates. For tight programs, that generalization of completion is known to match the stable model semantics, which is the basis of answer set programming. We show that the tightness condition in this theorem can be replaced by a less restrictive “local tightness” requirement. From this fact we conclude that the proof assistant <span>anthem-p2p</span> can be used to verify equivalence between locally tight programs.</p>","PeriodicalId":49436,"journal":{"name":"Theory and Practice of Logic Programming","volume":"84 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139497385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}