scholarly journals Role Forgetting for ALCOQH(universal role)-Ontologies Using an Ackermann-Based Approach

2017 ◽  
Author(s):  
Yizheng Zhao ◽  
Renate A. Schmidt
Keyword(s):  
Real World ◽  
Description Logic ◽  
Description Logics ◽  
Practical Method ◽  
Semantic Role ◽  
Success Rates ◽  
Reasoning Problem ◽  
Performance Results

Forgetting refers to a non-standard reasoning problem concerned with eliminating concept and role symbols from description logic-based ontologies while preserving all logical consequences up to the remaining symbols. Whereas previous research has primarily focused on forgetting concept symbols, in this paper, we turn our attention to role symbol forgetting. In particular, we present a practical method for semantic role forgetting for ontologies expressible in the description logic ALCOQH(universal role), i.e., the basic description logic ALC extended with nominals, qualified number restrictions, role inclusions and the universal role. Being based on an Ackermann approach, the method is the only approach so far for forgetting role symbols in description logics with qualified number restrictions. The method is goal-oriented and incremental. It always terminates and is sound in the sense that the forgetting solution is equivalent to the original ontology up to the forgotten symbols possibly with new concept definer symbols. Despite our method not being complete, performance results of an evaluation with a prototypical implementation have shown very good success rates on real-world ontologies.

scholarly journals A Practical Approach to Forgetting in Description Logics with Nominals

2020 ◽  
Vol 34 (03) ◽  
pp. 3073-3079
Author(s):  
Yizheng Zhao ◽  
Renate Schmidt ◽  
Yuejie Wang ◽  
Xuanming Zhang ◽  
Hao Feng
Keyword(s):  
Description Logic ◽  
Description Logics ◽  
Practical Method ◽  
Practical Approach ◽  
Ontology Engineering ◽  
Success Rates ◽  
Prototype Implementation ◽  
Speed Up

This paper investigates the problem of forgetting in description logics with nominals. In particular, we develop a practical method for forgetting concept and role names from ontologies specified in the description logic ALCO, extending the basic ALC with nominals. The method always terminates, and is sound in the sense that the forgetting solution computed by the method has the same logical consequences with the original ontology. The method is so far the only approach to deductive forgetting in description logics with nominals. An evaluation of a prototype implementation shows that the method achieves a significant speed-up and notably better success rates than the Lethe tool which performs deductive forgetting for ALC-ontologies. Compared to Fame, a semantic forgetting tool for ALCOIH-ontologies, better success rates are attained. From the perspective of ontology engineering this is very useful, as it provides ontology curators with a powerful tool to produce views of ontologies.

scholarly journals Attributed Description Logics: Reasoning on Knowledge Graphs

2018 ◽  
Author(s):  
Markus Krötzsch ◽  
Maximilian Marx ◽  
Ana Ozaki ◽  
Veronika Thost
Keyword(s):  
Real World ◽  
Description Logic ◽  
Description Logics ◽  
World Knowledge ◽  
Finite Sets ◽  
Knowledge Graphs ◽  
Attribute Value

In modelling real-world knowledge, there often arises a need to represent and reason with meta-knowledge. To equip description logics (DLs) for dealing with such ontologies, we enrich DL concepts and roles with finite sets of attribute–value pairs, called annotations, and allow concept inclusions to express constraints on annotations. We investigate a range of DLs starting from the lightweight description logic EL, covering the prototypical ALCH, and extending to the very expressive SROIQ, the DL underlying OWL 2 DL.

scholarly journals On Concept Forgetting in Description Logics with Qualified Number Restrictions

2018 ◽  
Author(s):  
Yizheng Zhao ◽  
Renate Schmidt
Keyword(s):  
Description Logic ◽  
Description Logics ◽  
Practical Method ◽  
Test Cases ◽  
Biomedical Ontologies ◽  
Large Corpus

This paper presents a practical method for computing solutions of concept forgetting in the description logic ALCOQ(neg,and,or), basic ALC extended with nominals, qualified number restrictions, role negation, role conjunction and role disjunction. The method is based on a non-trivial generalisation of Ackermann's Lemma, and attempts to compute either semantic solutions of concept forgetting or uniform interpolants in ALCOQ(neg,and,or). It is so far the only approach to concept forgetting in description logics with number restrictions plus nominals, as well as in description logics with ABoxes. Results of an evaluation with a prototypical implementation have shown that the method was successful in more than 90% of the test cases from a large corpus of biomedical ontologies. In only 13.2% of these cases the solutions were semantic solutions.

scholarly journals A NEUTROSOPHIC DESCRIPTION LOGIC

2008 ◽  
Vol 04 (03) ◽  
pp. 273-290
Author(s):  
HAIBIN WANG ◽  
ANDRÉ ROGATKO ◽  
FLORENTIN SMARANDACHE ◽  
RAJSHEKHAR SUNDERRAMAN
Keyword(s):  
Real World ◽  
Description Logic ◽  
Description Logics ◽  
Constraint Propagation ◽  
The Real ◽  
Neutrosophic Logic ◽  
Structured Knowledge

Description Logics (DLs) are appropriate, widely used, logics for managing structured knowledge. They allow reasoning about individuals and concepts, i.e. set of individuals with common properties. Typically, DLs are limited to dealing with crisp, well defined concepts. That is, concepts for which the problem whether an individual is an instance of it is a yes/no question. More often than not, the concepts encountered in the real world do not have a precisely defined criteria of membership: we may say that an individual is an instance of a concept only to a certain degree, depending on the individual's properties. The DLs that deal with such fuzzy concepts are called fuzzy DLs. In order to deal with fuzzy, incomplete, indeterminate and inconsistent concepts, we need to extend the capabilities of fuzzy DLs further. In this paper, we will present an extension of fuzzy [Formula: see text], combining Smarandache's neutrosophic logic with a classical DL. In particular, concepts become neutrosophic (here neutrosophic means fuzzy, incomplete, indeterminate and inconsistent), thus, reasoning about such neutrosophic concepts is supported. We will define its syntax, its semantics, describe its properties and present a constraint propagation calculus for reasoning.

A Simple and Practical Method for Incorporating Augmented Reality into the Classroom and Laboratory

2018 ◽  
Author(s):  
Kyle Plunkett
Keyword(s):  
Organic Chemistry ◽  
Augmented Reality ◽  
Real Time ◽  
Real World ◽  
Smart Phone ◽  
Practical Method ◽  
Virtual Expert ◽  
Video Projection

This manuscript provides two demonstrations of how Augmented Reality (AR), which is the projection of virtual information onto a real-world object, can be applied in the classroom and in the laboratory. Using only a smart phone and the free HP Reveal app, content rich AR notecards were prepared. The physical notecards are based on Organic Chemistry I reactions and show only a reagent and substrate. Upon interacting with the HP Reveal app, an AR video projection shows the product of the reaction as well as a real-time, hand-drawn curved-arrow mechanism of how the product is formed. Thirty AR notecards based on common Organic Chemistry I reactions and mechanisms are provided in the Supporting Information and are available for widespread use. In addition, the HP Reveal app was used to create AR video projections onto laboratory instrumentation so that a virtual expert can guide the user during the equipment setup and operation.

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 Capability-oriented architectural analysis method based on fuzzy description logic

2016 ◽  
Vol 13 (1) ◽  
pp. 287-308 ◽  
Author(s):  
Zhang Tingting ◽  
Liu Xiaoming ◽  
Wang Zhixue ◽  
Dong Qingchao
Keyword(s):  
Business Strategy ◽  
Domain Knowledge ◽  
Description Logic ◽  
Description Logics ◽  
Model Verification ◽  
Architectural Analysis ◽  
Requirements Modeling ◽  
Strategy Model ◽  
Domain Specific Modeling ◽  
Fuzzy Description

A number of problems may arise from architectural requirements modeling, including alignment of it with business strategy, model integration and handling the uncertain and vague information. The paper introduces a method for modeling architectural requirements in a way of ontology-based and capability-oriented requirements elicitation. The requirements can be modeled within a three-layer framework. The Capability Meta-concept Framework is provided at the top level. The domain experts can capture the domain knowledge within the framework, forming the domain ontology at the second level. The domain concepts can be used for extending the UML to produce a domain-specific modeling language. A fuzzy UML is introduced to model the vague and uncertain features of the capability requirements. An algorithm is provided to transform the fuzzy UML models into the fuzzy Description Logics ontology for model verification. A case study is given to demonstrate the applicability of the method.

scholarly journals Unifying Class-Based Representation Formalisms

1999 ◽  
Vol 11 ◽  
pp. 199-240 ◽  
Author(s):  
D. Calvanese ◽  
M. Lenzerini ◽  
D. Nardi
Keyword(s):  
Knowledge Representation ◽  
Description Logic ◽  
Description Logics ◽  
Expressive Power ◽  
Finite Model ◽  
Functional Dependencies ◽  
Semantic Data ◽  
Representation Systems ◽  
Frame Systems ◽  
Essential Set

The notion of class is ubiquitous in computer science and is central in many formalisms for the representation of structured knowledge used both in knowledge representation and in databases. In this paper we study the basic issues underlying such representation formalisms and single out both their common characteristics and their distinguishing features. Such investigation leads us to propose a unifying framework in which we are able to capture the fundamental aspects of several representation languages used in different contexts. The proposed formalism is expressed in the style of description logics, which have been introduced in knowledge representation as a means to provide a semantically well-founded basis for the structural aspects of knowledge representation systems. The description logic considered in this paper is a subset of first order logic with nice computational characteristics. It is quite expressive and features a novel combination of constructs that has not been studied before. The distinguishing constructs are number restrictions, which generalize existence and functional dependencies, inverse roles, which allow one to refer to the inverse of a relationship, and possibly cyclic assertions, which are necessary for capturing real world domains. We are able to show that it is precisely such combination of constructs that makes our logic powerful enough to model the essential set of features for defining class structures that are common to frame systems, object-oriented database languages, and semantic data models. As a consequence of the established correspondences, several significant extensions of each of the above formalisms become available. The high expressiveness of the logic we propose and the need for capturing the reasoning in different contexts forces us to distinguish between unrestricted and finite model reasoning. A notable feature of our proposal is that reasoning in both cases is decidable. We argue that, by virtue of the high expressive power and of the associated reasoning capabilities on both unrestricted and finite models, our logic provides a common core for class-based representation formalisms.

scholarly journals 2247. Real-world Experience with Meropenem–Vaborbactam (M/V) for Treatment of Carbapenem-Resistant Enterobacteriaceae (CRE) Infections

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S768-S768
Author(s):  
Ryan K Shields ◽  
Erin K McCreary ◽  
Rachel V Marini ◽  
Ellen G Kline ◽  
Chelsea E Jones ◽  
...  
Keyword(s):  
Real World ◽  
Survival Rates ◽  
Gene Promoter ◽  
Recurrent Infection ◽  
Success Rates ◽  
E Coli ◽  
Pcr Products ◽  
Infection Types ◽  
Intra Abdominal Infection

Abstract Background M/V demonstrates in vitro activity against KPC-producing CRE, but real-world clinical experience is limited. Methods Patients treated for > 48 hours with M/V for CRE infections were included. Success was defined as improved symptoms, absence of recurrent infection, and survival at 30 days. Microbiologic failures (MF) were defined as isolation of the same species post-treatment (tx). KPC and ompK36 mutations were detected by sequencing of PCR products. Results 19 patients were included; 58% were men; median age was 53. 11% were transplant recipients and median Charlson score was 3 (range: 0–10). Infection types included bacteremia (n = 7), pneumonia (6; 5 ventilator-associated), soft tissue (2), tracheobronchitis (2), intra-abdominal (1), and pyelonephritis (1). 68% of patients were in the ICU; median APACHE II and SOFA scores were 18 (7–40) and 4 (1–13), respectively. CR pathogens included K. pneumoniae (14), K. oxytoca (2), E. coli (2), and C. freundii (1); 89% harbored KPC, including KPC-2 (6), KPC-3 (10), and KPC-3 with a D179Y mutation (1). All were susceptible to M/V (median MIC = 0.03 µg/mL [0.015–0.12]). Median duration of tx was 8 days (3 – 28); 89% received monotherapy. Success and survival rates at 30d were 63% and 89%, respectively. Failures were due to death (2), recurrent infection (2), worse symptoms (2), and persistent bacteremia (1). Success rates for bacteremia and pneumonia were 57% and 67%, respectively. MF within 90 days occurred in 32% due to K. pneumoniae (5) or E. coli (1). MF were classified as intra-abdominal abscess (3), pneumonia (1), and respiratory (1) or urinary (1) colonization. The median time to MF was 32 days (15 – 67). M/V MICs were increased ≥8-fold against 67% (4/6) of recurrent isolates. 1 pt developed intra-abdominal infection due to M/V non-susceptible KPC-3 K. pneumoniae isolate (MIC = 8) following a 12-day of M/V; the recurrent isolate differed from the parent by an IS5 insertion in the ompK36 gene promoter. M/V was well-tolerated, 1 patient developed eosinophilia. Conclusion In this cohort of critically-ill patients with CRE infection, tx with M/V yielded outcomes comparable to prior cohorts treated with ceftazidime–avibactam. M/V non-susceptibility emerged in 1 isolate. Our findings require validation in future studies. Disclosures All authors: No reported disclosures.

Reasoning on the Semantic Web

2011 ◽  
pp. 110-133
Author(s):  
R. Brussee
Keyword(s):  
Real World ◽  
Description Logic ◽  
World Knowledge ◽  
Closed World Assumption ◽  
Sharp Distinction ◽  
Ontology Language ◽  
Closed World ◽  
Present Information ◽  
Logical Modeling ◽  
Case Reasoning

We describe reasoning as the process needed for using logic. Efficiently performing this process is a prerequisite for using logic to present information in a declarative way and to construct models of reality. In particular we describe description logic and the owl ontology language and explain that in this case reasoning amounts to graph completion operations that can be performed by a computer program. We give an extended example, modeling a building with wireless routers and explain how such a model can help in determining the location of resources. We emphasize how different assumptions on the way routers and buildings work are formalized and made explicit in our logical modeling, and explain the sharp distinction between knowing some facts and knowing all facts (open vs. closed world assumption). This should be helpful when using ontologies in applications needing incomplete real world knowledge.

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