Evidence map›Paper›PMID 33806451›Full record

ArticleEntropy (Basel, Switzerland)2021

A Structural Entropy Measurement Principle of Propositional Formulas in Conjunctive Normal Form.

Zaijun Zhang, Daoyun Xu, Jincheng Zhou

Abstract read
In one paragraph

Article in Entropy (Basel, Switzerland), 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

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0cells of the map it votes in
3citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

Who cites it

3 citing papers in PubMed.

  1. CCTFv2: Modeling Cyber Competitions.Entropy (Basel, Switzerland) · 2024
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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Zaijun ZhangCollege of Computer Science and Technology, Guizhou University, Guiyang 550025, China.ORCID 0000-0002-0016-2419
Daoyun XuCollege of Computer Science and Technology, Guizhou University, Guiyang 550025, China.
Jincheng ZhouKey Laboratory of Complex Systems and Intelligent Computing and School of Mathematics and Statistics, Qiannan Normal University for Nationalities, Duyun 558000, China.

Funding

the General program of Qiannan Normal University for Nationalities of China qnsy2018016the Industrial Technology Foundation of Qiannan State of China Qiannan Ke He Gong Zi (2017) 16 Haothe National Natural Science Foundation of China 61762019the National Natural Science Foundation of China 61862051the National Natural Science Foundation of China 62062001the Nature Science Foundation of Qiannan [2017]10the Science and Technology Foundation of Guizhou Province NO. [2019]1299the Top-notch Talent Program of of Guizhou province KY[2018]080the Young Science and Technology Talent Growth Fund Project of Education Department of Guizhou Province of China Qian Jiao He KY Zi[2017]343the Young Science and Technology Talent Growth Fund Project of Education Department of Guizhou Province of China Qian Jiao He KY Zi[2017]354the Young Science and Technology Talent Growth Fund Project of Education Department of Guizhou Province of China Qian Jiao He KY Zi [2018]411
6 · The paper itself

Abstract

The satisfiability (SAT) problem is a core problem in computer science. Existing studies have shown that most industrial SAT instances can be effectively solved by modern SAT solvers while random SAT instances cannot. It is believed that the structural characteristics of different SAT formula classes are the reasons behind this difference. In this paper, we study the structural properties of propositional formulas in conjunctive normal form (CNF) by the principle of structural entropy of formulas. First, we used structural entropy to measure the complex structure of a formula and found that the difficulty solving the formula is related to the structural entropy of the formula. The smaller the compressing information of a formula, the more difficult it is to solve the formula. Secondly, we proposed a λ-approximation strategy to approximate the structural entropy of large formulas. The experimental results showed that the proposed strategy can effectively approximate the structural entropy of the original formula and that the approximation ratio is more than 92%. Finally, we analyzed the structural properties of a formula in the solution process and found that a local search solver tends to select variables in different communities to perform the next round of searches during a search and that the structural entropy of a variable affects the probability of the variable being flipped. By using these conclusions, we also proposed an initial candidate solution generation strategy for a local search for SAT, and the experimental results showed that this strategy effectively improves the performance of the solvers CCAsat and Sparrow2011 when incorporated into these two solvers.

Indexed as

CNF formulaSAT problemstructural entropystructural propertiesthe structural complexity

Identifiers

PMID33806451
PMCPMC8001598

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.