Adding Metalogic Features to Knowledge Representation Languages*

2021 ◽  
Vol 181 (1) ◽  
pp. 71-98
Author(s):  
Stefania Costantini ◽  
Andrea Formisano
Keyword(s):  
Knowledge Representation ◽  
Relevant Literature ◽  
Operational Semantics ◽  
Answer Set Programming ◽  
The Other ◽  
Knowledge Representation And Reasoning ◽  
Knowledge Engineer ◽  
Meta Level ◽  
The One ◽  
Programming Paradigms

In this paper we present a methodology for introducing customizable metalogic features in logic-based knowledge representation and reasoning languages. The proposed approach is based on concepts of introspection and reflection previously introduced and discussed by various authors in relevant literature. This allows a knowledge engineer to specify enhanced reasoning engines by defining properties and meta-properties of relations as expressible for instance in OWL. We employ meta-level axiom schemata based upon a naming (reification) device. We propose general principles for extending the semantics of “host” formalisms accordingly. Consequently, suitable pre-defined libraries of properties can be made available, while user-defined new schemata are also allowed. We make the specific cases of Answer Set Programming (ASP) and Datalog±, where such features may be part of software engineering toolkits for these programming paradigms. On the one hand, concerning ASP, we extend the programming principles and practice to accommodate the proposed methodology, so as to perform meta-reasoning within the plain ASP semantics. The computational complexity of the resulting framework does not change. On the other hand, we show how metalogic features can significantly enrich Datalog± with minor changes to its operational semantics (provided in terms of “chase”) and, also in this case, no additional complexity burden.

scholarly journals Beyond NP: Quantifying over Answer Sets

2019 ◽  
Vol 19 (5-6) ◽  
pp. 705-721
Author(s):  
GIOVANNI AMENDOLA ◽  
FRANCESCO RICCA ◽  
MIROSLAW TRUSZCZYNSKI
Keyword(s):  
Answer Set Programming ◽  
The Other ◽  
Polynomial Hierarchy ◽  
Programming Paradigm ◽  
Quantified Boolean Formulas ◽  
Boolean Formulas ◽  
The One ◽  
Image Position ◽  
Answer Sets ◽  
Computational Properties

AbstractAnswer Set Programming (ASP) is a logic programming paradigm featuring a purely declarative language with comparatively high modeling capabilities. Indeed, ASP can model problems in NP in a compact and elegant way. However, modeling problems beyond NP with ASP is known to be complicated, on the one hand, and limited to problems in $\[\Sigma _2^P\]$ on the other. Inspired by the way Quantified Boolean Formulas extend SAT formulas to model problems beyond NP, we propose an extension of ASP that introduces quantifiers over stable models of programs. We name the new language ASP with Quantifiers (ASP(Q)). In the paper we identify computational properties of ASP(Q); we highlight its modeling capabilities by reporting natural encodings of several complex problems with applications in artificial intelligence and number theory; and we compare ASP(Q) with related languages. Arguably, ASP(Q) allows one to model problems in the Polynomial Hierarchy in a direct way, providing an elegant expansion of ASP beyond the class NP.

Concepts, Knowledge and Language in Healthcare Information Systems: Follow-up 30 Months Later

1998 ◽  
Vol 37 (04/05) ◽  
pp. 312-314
Author(s):  
J.-R. Scherrer
Keyword(s):  
Knowledge Representation ◽  
Research And Development ◽  
Computational Linguistics ◽  
The Other ◽  
Conceptual Approach ◽  
Healthcare Information Systems ◽  
The One ◽  
New Research ◽  
Insight Into

AbstractThe paper reviews the last IMIA-WG6 recommendations, issued along two themes: (1) how to better share common results and (2) how to conduct new research and development efforts. Some of the major discrepancies in the field are reviewed. The paper intends to offer insight into two areas, first, in the issue of knowledge representation and, second, in the science of meaning, incorporating the broad intersection of computational linguistics, semantics, conceptual approach, and denotation. The Ogden-Richards meaning triangle is used as a convenient organizing principle to maximize the scope of understanding among the different schools, particularly in areas of linguistics and semantics on the one side and denotation and conceptual approach on the other. In conclusion, there is a need for clarification and for more scientific pragmatism.

The varieties of ethical experience

2014 ◽  
Vol 2014 (1) ◽  
pp. 155-190
Author(s):  
Peter J. Rosan
Keyword(s):  
Empirical Research ◽  
Relevant Literature ◽  
Well Being ◽  
The Other ◽  
Ethical Life ◽  
Precise Form ◽  
Other Hand ◽  
The Subject ◽  
The One ◽  
Ways Of Being

This article offers original phenomenological descriptions of empathy, sympathy, and compassion. These descriptions are based on empirical research, and they sample the variety of ways the subject may respond to the suffering of another person. The structure of these different, but similar ways of being are then taken up as clues hinting at a sensibility bearing on the formation of an ethical life. This sensibility is essentially twofold in character. On the one hand, a pairing of the perceived similarities between subject and other opens the subject to a resonance with the humanity of the other. On the other hand, the other’s expressive life awakens the subject’s interest in wanting to know the meaning of these expressions for the other or calls forth a caring regard for the well-being of the other. The ways of being represented by empathy, sympathy, and compassion may be viewed as different ways of organizing or rendering a precise form to the constitutive strands of the aforementioned sensibility. The relevant literature in phenomenology and ethics is commented on as it informs the discussion, but is kept to a minimum.

scholarly journals Tractable answer-set programming with weight constraints: bounded treewidth is not enough

2012 ◽  
Vol 14 (2) ◽  
pp. 141-164 ◽  
Author(s):  
REINHARD PICHLER ◽  
STEFAN RÜMMELE ◽  
STEFAN SZEIDER ◽  
STEFAN WOLTRAN
Keyword(s):  
Knowledge Representation ◽  
Linear Time ◽  
Answer Set Programming ◽  
Knowledge Representation And Reasoning ◽  
Cardinality Constraints ◽  
Bounded Treewidth ◽  
Straightforward Application ◽  
Intractable Problems ◽  
Important Extension ◽  
Answer Set

AbstractCardinality constraints or, more generally, weight constraints are well recognized as an important extension of answer-set programming. Clearly, all common algorithmic tasks related to programs with cardinality or weight constraints – like checking the consistency of a program – are intractable. Many intractable problems in the area of knowledge representation and reasoning have been shown to become linear time tractable if the treewidth of the programs or formulas under consideration is bounded by some constant. The goal of this paper is to apply the notion of treewidth to programs with cardinality or weight constraints and to identify tractable fragments. It will turn out that the straightforward application of treewidth to such class of programs does not suffice to obtain tractability. However, by imposing further restrictions, tractability can be achieved.

scholarly journals Applications of Answer Set Programming

AI Magazine ◽  
2016 ◽  
Vol 37 (3) ◽  
pp. 53-68 ◽  
Author(s):  
Esra Erdem ◽  
Michael Gelfond ◽  
Nicola Leone
Keyword(s):  
Computational Biology ◽  
Knowledge Representation ◽  
Continuous Improvement ◽  
Answer Set Programming ◽  
Industrial Applications ◽  
Knowledge Representation And Reasoning ◽  
Wide Range ◽  
Answer Set

ASP has been applied fruitfully to a wide range of areas in AI and in other fields, both in academia and in industry, thanks to the expressive representation languages of ASP and the continuous improvement of ASP solvers. We present some of these ASP applications, in particular, in knowledge representation and reasoning, robotics, bioinformatics and computational biology as well as some industrial applications. We discuss the challenges addressed by ASP in these applications and emphasize the strengths of ASP as a useful AI paradigm.

The Chronicity of Schizophrenia in North West India

1978 ◽  
Vol 132 (2) ◽  
pp. 186-190 ◽  
Author(s):  
P. Kulhara ◽  
N. N. Wig
Keyword(s):  
United Kingdom ◽  
Relevant Literature ◽  
The Other ◽  
Urban Setting ◽  
Western World ◽  
North West ◽  
Follow Up Study ◽  
The United Kingdom ◽  
The One

The results of a follow-up study of schizophrenics attending a centre in North West India are reported. The relevant literature is reviewed, The results were compared with two well-known studies, one from the United Kingdom and the other from Mauritius. The evidence presented suggests that the course taken by schizophrenia in a newly-developed city and its neighbourhood in this part of India is similar to the one seen in the Western world. This study does not support the view that chronicity of schizophrenia in non-European, non-white populations is different, at least in an urban setting.

scholarly journals Symmetry breaking in a new stable model search method

10.29007/1l5r ◽  
2018 ◽  
Author(s):  
Tarek Khaled ◽  
Belaid Benhamou
Keyword(s):  
Knowledge Representation ◽  
Symmetry Breaking ◽  
Constraint Programming ◽  
Answer Set Programming ◽  
Search Tree ◽  
Search Method ◽  
Combinatorial Problems ◽  
Knowledge Representation And Reasoning ◽  
Stable Model ◽  
Model Search

In this work, we investigate the inclusion of symmetry breaking in the answer set programming (ASP) framework. The notion of symmetry is widely studied in various domains. Particularly, in the field of constraint programming, where symmetry breaking made a significant improvement in the performances of many constraint solvers. Usually, combinatorial problems contain a lot of symmetries that could render their resolution difficult for the solvers that do not consider them. Indeed, these symmetries guide the solvers in the useless exploration of symmetric and redundant branches of the search tree. The ASP framework is well-known in knowledge representation and reasoning. How- ever, only few works on symmetry in ASP exist. We propose in this paper a new ASP solver based on a novel semantics that we enhance by symmetry breaking. This method with symmetry elimination is implemented and used for the resolution of a large variety of combinatorial problems. The obtained results are very promising and showcase an advantage when using our method in comparison to other known ASP methods.

scholarly journals Evaluation Techniques and Systems for Answer Set Programming: a Survey

2018 ◽  
Author(s):  
Martin Gebser ◽  
Nicola Leone ◽  
Marco Maratea ◽  
Simona Perri ◽  
Francesco Ricca ◽  
...  
Keyword(s):  
Knowledge Representation ◽  
Answer Set Programming ◽  
Knowledge Representation And Reasoning ◽  
Modeling Language ◽  
Scientific Applications ◽  
Two Factors ◽  
History Of ◽  
Evaluation Techniques ◽  
Answer Set

Answer set programming (ASP) is a prominent knowledge representation and reasoning paradigm that found both industrial and scientific applications. The success of ASP is due to the combination of two factors: a rich modeling language and the availability of efficient ASP implementations. In this paper we trace the history of ASP systems, describing the key evaluation techniques and their implementation in actual tools.

Sign in / Sign up

Export Citation Format

Share Document