scholarly journals Acquiring Ontology Axioms through Mappings to Data Sources

2019 ◽  
Vol 11 (12) ◽  
pp. 260
Author(s):  
Floriana Di Pinto ◽  
Giuseppe De Giacomo ◽  
Domenico Lembo ◽  
Maurizio Lenzerini ◽  
Riccardo Rosati
Keyword(s):  
Knowledge Base ◽  
Description Logic ◽  
Description Logics ◽  
Data Access ◽  
Data Sources ◽  
New Concepts ◽  
Source Data ◽  
Meta Modeling ◽  
Definition Of ◽  
Do So

Although current languages used in ontology-based data access (OBDA) systems allow for mapping source data to instances of concepts and relations in the ontology, several application domains need more flexible tools for inferring knowledge from data, which are able to dynamically acquire axioms about new concepts and relations directly from the data. In this paper we introduce the notion of mapping-based knowledge base (MKB) to formalize the situation where both the extensional and the intensional level of the ontology are determined by suitable mappings to a set of data sources. This allows for making the intensional level of the ontology as dynamic as the extensional level traditionally is. To do so, we resort to the meta-modeling capabilities of higher-order description logics, in particular the description logic Hi ( DL-Lite R ) , which allows seeing concepts and relations as individuals, and vice versa. The challenge in this setting is to design efficient algorithms for answering queries posed to MKBs. Besides the definition of MKBs, our main contribution is to prove that answering instance queries posed to MKBs expressed in Hi ( DL-Lite R ) can be done efficiently.

scholarly journals КОГНИТИВНЫЙ ПРОТОТИП КАК СТРУКТУРА ДАННЫХ ДЛЯ ХРАНЕНИЯ МОДЕЛЕЙ КОГНИТИВНЫХ СТРУКТУР

2016 ◽  
Author(s):  
O. A. Ryzhov ◽  
A. M. Popov
Keyword(s):  
Data Structure ◽  
Knowledge Base ◽  
Cognitive Structures ◽  
Formal Models ◽  
New Concepts ◽  
Computer Environment ◽  
Definition Of

The analysis of formal models of knowledge representaion in human minds allowed us to forge a definition of two new concepts: cognitive prototype (CP) as a processable and flexible data structure for representing models of cognitive structures (CS) in computer environment and knowledge base (KB) of IES based on CPs as a UML-model to storage and further process the content of educational courses based on cognitive prototypes.

Answering Continuous Description Logic Queries

2016 ◽  
pp. 893-938
Author(s):  
Carlos Bobed ◽  
Fernando Bobillo ◽  
Sergio Ilarri ◽  
Eduardo Mena
Keyword(s):  
Mobile Computing ◽  
Description Logic ◽  
Description Logics ◽  
Data Access ◽  
Location Data ◽  
Novel Approach ◽  
Continuous Description ◽  
Efficient Data ◽  
Continuous Query Processing ◽  
Computing Environments

During the last years, mobile computing has been the focus of many research efforts, due mainly to the ever-growing use of mobile devices. In this context, there is a need to manage dynamic data, such as location data or other data provided by sensors. As an example, the continuous processing of location-dependent queries has been the subject of thorough research. However, there is still a need of highly expressive ways of formulating queries, augmenting in this way the systems' answer capabilities. Regarding this issue, the modeling power of Description Logics (DLs) and the inferring capabilities of their attached reasoners could fulfill this new requirement. The main problem is that DLs are inherently oriented to model static knowledge, that is, to capture the nature of the modeled objects, but not to handle changes in the property values (which requires a full ontology reclassification), as it is common in mobile computing environments (e.g., the location is expected to vary continually). In this paper, the authors present a novel approach to process continuous queries that combines 1) the DL reasoning capabilities to deal with static knowledge, with 2) the efficient data access provided by a relational database to deal with volatile knowledge. By marking at modeling time the properties that are expected to change during the lifetime of the queries, the authors'system is able to exploit both the results of the classification process provided by a DL reasoner, and the low computational costs of a database when accessing changing data (mobile environments, semantic sensors, etc.), following a two-step continuous query processing that enables us to handle continuous DL queries efficiently. Experimental results show the feasibility of the authors' approach.

scholarly journals Beth Definability in Expressive Description Logics

2013 ◽  
Vol 48 ◽  
pp. 347-414 ◽  
Author(s):  
B. Ten Cate ◽  
E. Franconi ◽  
I. Seylan
Keyword(s):  
Description Logic ◽  
Description Logics ◽  
Complete Classification ◽  
Property A ◽  
Explicit Definition ◽  
Finite Structures ◽  
Double Exponential ◽  
Beth Definability ◽  
Definition Of

The Beth definability property, a well-known property from classical logic, is investigated in the context of description logics: if a general L-TBox implicitly defines an L-concept in terms of a given signature, where L is a description logic, then does there always exist over this signature an explicit definition in L for the concept? This property has been studied before and used to optimize reasoning in description logics. In this paper a complete classification of Beth definability is provided for extensions of the basic description logic ALC with transitive roles, inverse roles, role hierarchies, and/or functionality restrictions, both on arbitrary and on finite structures. Moreover, we present a tableau-based algorithm which computes explicit definitions of at most double exponential size. This algorithm is optimal because it is also shown that the smallest explicit definition of an implicitly defined concept may be double exponentially long in the size of the input TBox. Finally, if explicit definitions are allowed to be expressed in first-order logic, then we show how to compute them in single exponential time.

Answering Continuous Description Logic Queries

2014 ◽  
Vol 10 (3) ◽  
pp. 1-44 ◽  
Author(s):  
Carlos Bobed ◽  
Fernando Bobillo ◽  
Sergio Ilarri ◽  
Eduardo Mena
Keyword(s):  
Mobile Computing ◽  
Description Logic ◽  
Description Logics ◽  
Data Access ◽  
Location Data ◽  
Novel Approach ◽  
Continuous Description ◽  
Efficient Data ◽  
Continuous Query Processing ◽  
Computing Environments

During the last years, mobile computing has been the focus of many research efforts, due mainly to the ever-growing use of mobile devices. In this context, there is a need to manage dynamic data, such as location data or other data provided by sensors. As an example, the continuous processing of location-dependent queries has been the subject of thorough research. However, there is still a need of highly expressive ways of formulating queries, augmenting in this way the systems' answer capabilities. Regarding this issue, the modeling power of Description Logics (DLs) and the inferring capabilities of their attached reasoners could fulfill this new requirement. The main problem is that DLs are inherently oriented to model static knowledge, that is, to capture the nature of the modeled objects, but not to handle changes in the property values (which requires a full ontology reclassification), as it is common in mobile computing environments (e.g., the location is expected to vary continually). In this paper, the authors present a novel approach to process continuous queries that combines 1) the DL reasoning capabilities to deal with static knowledge, with 2) the efficient data access provided by a relational database to deal with volatile knowledge. By marking at modeling time the properties that are expected to change during the lifetime of the queries, the authors'system is able to exploit both the results of the classification process provided by a DL reasoner, and the low computational costs of a database when accessing changing data (mobile environments, semantic sensors, etc.), following a two-step continuous query processing that enables us to handle continuous DL queries efficiently. Experimental results show the feasibility of the authors' approach.

scholarly journals £-Single Valued Extremally Disconnected Ideal Neutrosophic Topological Spaces

Symmetry ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 53
Author(s):  
Fahad Alsharari
Keyword(s):  
Topological Spaces ◽  
Neutrosophic Sets ◽  
Extremally Disconnected ◽  
Fundamental Properties ◽  
Separation Axioms ◽  
New Concepts ◽  
Definition Of

This paper aims to mark out new concepts of r-single valued neutrosophic sets, called r-single valued neutrosophic £-closed and £-open sets. The definition of £-single valued neutrosophic irresolute mapping is provided and its characteristic properties are discussed. Moreover, the concepts of £-single valued neutrosophic extremally disconnected and £-single valued neutrosophic normal spaces are established. As a result, a useful implication diagram between the r-single valued neutrosophic ideal open sets is obtained. Finally, some kinds of separation axioms, namely r-single valued neutrosophic ideal-Ri (r-SVNIRi, for short), where i={0,1,2,3}, and r-single valued neutrosophic ideal-Tj (r-SVNITj, for short), where j={1,2,212,3,4}, are introduced. Some of their characterizations, fundamental properties, and the relations between these notions have been studied.

A Set-theoretic Approach to Reasoning Services for the Description Logic 𝒟 ℒ D 4,×

2020 ◽  
Vol 176 (3-4) ◽  
pp. 349-384
Author(s):  
Domenico Cantone ◽  
Marianna Nicolosi-Asmundo ◽  
Daniele Francesco Santamaria
Keyword(s):  
Description Logic ◽  
Description Logics ◽  
Theoretic Approach ◽  
The Novel ◽  
Data Types ◽  
Left Hand ◽  
Rule Languages ◽  
Tableau System ◽  
High Scalability ◽  
Better Than

In this paper we consider the most common TBox and ABox reasoning services for the description logic 𝒟ℒ〈4LQSR,x〉(D) ( 𝒟 ℒ D 4,× , for short) and prove their decidability via a reduction to the satisfiability problem for the set-theoretic fragment 4LQSR. 𝒟 ℒ D 4,× is a very expressive description logic. It combines the high scalability and efficiency of rule languages such as the SemanticWeb Rule Language (SWRL) with the expressivity of description logics. In fact, among other features, it supports Boolean operations on concepts and roles, role constructs such as the product of concepts and role chains on the left-hand side of inclusion axioms, role properties such as transitivity, symmetry, reflexivity, and irreflexivity, and data types. We further provide a KE-tableau-based procedure that allows one to reason on the main TBox and ABox reasoning tasks for the description logic 𝒟 ℒ D 4,× . Our algorithm is based on a variant of the KE-tableau system for sets of universally quantified clauses, where the KE-elimination rule is generalized in such a way as to incorporate the γ-rule. The novel system, called KEγ-tableau, turns out to be an improvement of the system introduced in [1] and of standard first-order KE-tableaux [2]. Suitable benchmark test sets executed on C++ implementations of the three mentioned systems show that in several cases the performances of the KEγ-tableau-based reasoner are up to about 400% better than the ones of the other two systems.

scholarly journals Accountability as a Virtue

2021 ◽  
pp. 095394682110097
Author(s):  
Andrew Torrance
Keyword(s):  
Definition Of ◽  
Do So

This opening article will offer a brief introduction to what it means to understand accountability as a virtue. To do so, I first propose a definition of the condition of accountability, which I go on to distinguish from responsibility. Based on this definition, I then present an account of the corresponding virtue of accountability.

scholarly journals Indistinguishability and Negative Probabilities

Entropy ◽  
2020 ◽  
Vol 22 (8) ◽  
pp. 829
Author(s):  
J. Acacio de Barros ◽  
Federico Holik
Keyword(s):  
Quantum Systems ◽  
Quantum Contextuality ◽  
No Signaling ◽  
Definition Of ◽  
Do So

In this paper, we examined the connection between quantum systems’ indistinguishability and signed (or negative) probabilities. We do so by first introducing a measure-theoretic definition of signed probabilities inspired by research in quantum contextuality. We then argue that ontological indistinguishability leads to the no-signaling condition and negative probabilities.

scholarly journals Examining and Fine-tuning the Selection of Glycan Compositions with GlyConnect Compozitor

2020 ◽  
Vol 19 (10) ◽  
pp. 1602-1618 ◽  
Author(s):  
Thibault Robin ◽  
Julien Mariethoz ◽  
Frédérique Lisacek
Keyword(s):  
Search Engine ◽  
Posttranslational Modifications ◽  
Search Engines ◽  
Web Application ◽  
Contextual Information ◽  
Fine Tuning ◽  
Data Sources ◽  
Web Interface ◽  
Definition Of ◽  
Selection Of

A key point in achieving accurate intact glycopeptide identification is the definition of the glycan composition file that is used to match experimental with theoretical masses by a glycoproteomics search engine. At present, these files are mainly built from searching the literature and/or querying data sources focused on posttranslational modifications. Most glycoproteomics search engines include a default composition file that is readily used when processing MS data. We introduce here a glycan composition visualizing and comparative tool associated with the GlyConnect database and called GlyConnect Compozitor. It offers a web interface through which the database can be queried to bring out contextual information relative to a set of glycan compositions. The tool takes advantage of compositions being related to one another through shared monosaccharide counts and outputs interactive graphs summarizing information searched in the database. These results provide a guide for selecting or deselecting compositions in a file in order to reflect the context of a study as closely as possible. They also confirm the consistency of a set of compositions based on the content of the GlyConnect database. As part of the tool collection of the Glycomics@ExPASy initiative, Compozitor is hosted at https://glyconnect.expasy.org/compozitor/ where it can be run as a web application. It is also directly accessible from the GlyConnect database.

New code for the protection of civilian population and property during armed conflict

1980 ◽  
Vol 20 (219) ◽  
pp. 287-315 ◽  
Author(s):  
Ionel Gloşcă
Keyword(s):  
International Law ◽  
Armed Conflict ◽  
Armed Conflicts ◽  
International Treaties ◽  
Civilian Population ◽  
State Activity ◽  
The Holocaust ◽  
Definition Of ◽  
Do So

One of the principles underlying international law applicable in armed conflicts is that no act of war is permitted against the civilian population, consisting, by definition, of persons who take no part in the hostilities.Until the holocaust of 1939–45, international law gave practically no real protection to the civilian population in the event of war, and was not even intended to do so since up to that time war was considered to be a State activity from which civilians remained aloof. There were, nonetheless, general principles and rules in various international treaties which, in one way or another, related also to the civilian population.

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