scholarly journals Finding Small Proofs for Description Logic Entailments: Theory and Practice

10.29007/nhpp ◽  
2020 ◽  
Author(s):  
Christian Alrabbaa ◽  
Franz Baader ◽  
Stefan Borgwardt ◽  
Patrick Koopmann ◽  
Alisa Kovtunova
Keyword(s):  
Description Logic ◽  
Theory And Practice ◽  
Proof Complexity ◽  
Reasoning Task ◽  
Worst Case ◽  
Derivation Step ◽  
Worst Case Complexity ◽  
Directed Hypergraphs ◽  
The Individual ◽  
Theoretical Side

Logic-based approaches to AI have the advantage that their behaviour can in principle be explained by providing their users with proofs for the derived consequences. However, if such proofs get very large, then it may be hard to understand a consequence even if the individual derivation steps are easy to comprehend. This motivates our interest in finding small proofs for Description Logic (DL) entailments. Instead of concentrating on a specific DL and proof calculus for this DL, we introduce a general framework in which proofs are represented as labeled, directed hypergraphs, where each hyperedge corresponds to a single sound derivation step. On the theoretical side, we investigate the complexity of deciding whether a certain consequence has a proof of size at most n along the following orthogonal dimensions: (i) the underlying proof system is polynomial or exponential; (ii) proofs may or may not reuse already derived consequences; and (iii) the number n is represented in unary or binary. We have determined the exact worst-case complexity of this decision problem for all but one of the possible combinations of these options. On the practical side, we have developed and implemented an approach for generating proofs for expressive DLs based on a non-standard reasoning task called forgetting. We have evaluated this approach on a set of realistic ontologies and compared the obtained proofs with proofs generated by the DL reasoner ELK, finding that forgetting-based proofs are often better w.r.t. different measures of proof complexity.

scholarly journals Submodel Decomposition for Solving Limited Memory Influence Diagrams (Student Abstract)

2020 ◽  
Vol 34 (10) ◽  
pp. 13851-13852
Author(s):  
Junkyu Lee
Keyword(s):  
Message Passing ◽  
Graphical Model ◽  
Partial Evaluation ◽  
Influence Diagrams ◽  
Influence Diagram ◽  
Worst Case ◽  
Limited Memory ◽  
Worst Case Complexity ◽  
The Individual ◽  
Model Approach

This paper presents a systematic way of decomposing a limited memory influence diagram (LIMID) to a tree of single-stage decision problems, or submodels and solving it by message passing. The relevance in LIMIDs is formalized by the notion of the partial evaluation of the maximum expected utility, and the graph separation criteria for identifying submodels follow. The submodel decomposition provides a graphical model approach for updating the beliefs and propagating the conditional expected utilities for solving LIMIDs with the worst-case complexity bounded by the maximum treewidth of the individual submodels.

scholarly journals Generic Preferences over Subsets of Structured Objects

2009 ◽  
Vol 34 ◽  
pp. 133-164 ◽  
Author(s):  
M. Binshtok ◽  
R. I. Brafman ◽  
C. Domshlak ◽  
S. E. Shiomony
Keyword(s):  
Empirical Evaluation ◽  
Efficient Manner ◽  
Worst Case ◽  
Case Complexity ◽  
Optimal Subset ◽  
Online Newspaper ◽  
Worst Case Complexity ◽  
Structured Objects ◽  
The Individual ◽  
Preference Specification

Various tasks in decision making and decision support systems require selecting a preferred subset of a given set of items. Here we focus on problems where the individual items are described using a set of characterizing attributes, and a generic preference specification is required, that is, a specification that can work with an arbitrary set of items. For example, preferences over the content of an online newspaper should have this form: At each viewing, the newspaper contains a subset of the set of articles currently available. Our preference specification over this subset should be provided offline, but we should be able to use it to select a subset of any currently available set of articles, e.g., based on their tags. We present a general approach for lifting formalisms for specifying preferences over objects with multiple attributes into ones that specify preferences over subsets of such objects. We also show how we can compute an optimal subset given such a specification in a relatively efficient manner. We provide an empirical evaluation of the approach as well as some worst-case complexity results.

scholarly journals Heuristic Optimization of Overloading Due to Electric Vehicles in a Low Voltage Grid

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 6069
Author(s):  
Sajjad Haider ◽  
Peter Schegner
Keyword(s):  
Electric Vehicles ◽  
Low Voltage ◽  
Optimization Methods ◽  
Monte Carlo Analysis ◽  
Heuristic Optimization ◽  
Optimization Approach ◽  
Worst Case ◽  
Voltage Drops ◽  
The Individual ◽  
Nodal Voltage

It is important to understand the effect of increasing electric vehicles (EV) penetrations on the existing electricity transmission infrastructure and to find ways to mitigate it. While, the easiest solution is to opt for equipment upgrades, the potential for reducing overloading, in terms of voltage drops, and line loading by way of optimization of the locations at which EVs can charge, is significant. To investigate this, a heuristic optimization approach is proposed to optimize EV charging locations within one feeder, while minimizing nodal voltage drops, cable loading and overall cable losses. The optimization approach is compared to typical unoptimized results of a monte-carlo analysis. The results show a reduction in peak line loading in a typical benchmark 0.4 kV by up to 10%. Further results show an increase in voltage available at different nodes by up to 7 V in the worst case and 1.5 V on average. Optimization for a reduction in transmission losses shows insignificant savings for subsequent simulation. These optimization methods may allow for the introduction of spatial pricing across multiple nodes within a low voltage network, to allow for an electricity price for EVs independent of temporal pricing models already in place, to reflect the individual impact of EVs charging at different nodes across the network.

News production theory and practice

Pragmatics ◽  
2008 ◽  
Vol 18 (1) ◽  
pp. 59-85 ◽  
Author(s):  
Tom Van Hout ◽  
Geert Jacobs
Keyword(s):  
Process Analysis ◽  
Theory And Practice ◽  
Computer Assisted ◽  
Press Releases ◽  
News Production ◽  
News Reports ◽  
Business News ◽  
Writing Practices ◽  
The Individual ◽  
And Control

This paper considers notions of agency, interaction and power in business news journalism. In the first part, we present a bird’s eye view of news access theory as it is reflected in selected sociological and anthropological literature on the ethnography of news production. Next, we show how these theoretical notions can be applied to the study of press releases and particularly to the linguistic pragmatic analysis of the specific social and textual practices that surround their transformation into news reports. Drawing on selected fieldwork data collected at the business desk of a major Flemish quality newspaper, we present an innovative methodology combining newsroom ethnography and computer-assisted writing process analysis which documents how a reporter discovers a story, introduces it into the newsroom, writes and reflects on it. In doing so, we put the individual journalist’s writing practices center stage, zoom in on the specific ways in which he interacts with sources and conceptualize power in terms of his dependence on press releases. Following Beeman & Peterson (2001), we argue in favor of a view of journalism as ‘interpretive practice’ and of news production as a process of entextualization involving multiple actors who struggle over authority, ownership and control.

Knowledge for the good of the individual and society: linking philosophy, disciplinary goals, theory, and practice

2010 ◽  
Vol 11 (1) ◽  
pp. 42-52 ◽  
Author(s):  
Mary K. McCurry ◽  
Susan M. Hunter Revell ◽  
Sr. Callista Roy
Keyword(s):  
Theory And Practice ◽  
The Individual

scholarly journals On the optimal order of worst case complexity of direct search

2015 ◽  
Vol 10 (4) ◽  
pp. 699-708 ◽  
Author(s):  
M. Dodangeh ◽  
L. N. Vicente ◽  
Z. Zhang
Keyword(s):  
Direct Search ◽  
Optimal Order ◽  
Worst Case ◽  
Case Complexity ◽  
Worst Case Complexity

Criminal law measures to combat provocation of crimes and falsification of criminals

2021 ◽  
pp. 127
Author(s):  
Viktor N. Borkov
Keyword(s):  
Law Enforcement ◽  
Criminal Law ◽  
Legal Status ◽  
Criminal Responsibility ◽  
Criminal Liability ◽  
Legal Aspects ◽  
Theory And Practice ◽  
Criminal Prosecution ◽  
Actual Problem ◽  
The Individual

The article examines the criminal-legal aspects of the actual problem of protecting the inviolability of the individual from the unacceptable activity of state representatives in the exercise of law enforcement functions. Topical issues for theory and practice of the legal nature of the provocation of crime and the falsification of criminals remain debatable. There are no unified approaches to the qualification of provocative and inflammatory actions and cases of "throwing" objects to citizens, for the turnover of which criminal responsibility arises, there is no theoretical justification for the criminal legal status of persons provoked to commit a crime. The article shows that the qualification of common cases of provocation of crimes and falsification of criminals according to the norms providing for liability for abuse of official authority, falsification of evidence or the results of operational investigative activities should be recognized as not accurate. At the same time, responsibility for these actions committed by subjects who are not officials, and without the participation of the latter, has not been established at all. The author proposes a draft criminal law provision providing for liability for inducing to commit a crime or its staging in order to illegally create grounds for criminal prosecution. The paper questions the approach according to which a person provoked by law enforcement officers to commit a crime is not subject to criminal liability regardless of the specifics of the encroachment.

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