activity
20102022
most citedOn variables with few occurrences in conjunctive normal forms

11 citations · 39 across the 12 of their papers we have counts for

collaborators

12 papers

cs.LO2022★ 2 cited

The Complexity and Expressive Power of Second-Order Extended Logic

Shiguang Feng, Xishun Zhao

We study the expressive powers of SO-HORN, SO-HORN and SO-HORN on all finite structures. We show that SO-HORN, SO-HORN, FO(LFP) coincide with each o…

cs.LO2022

Capturing the polynomial hierarchy by second-order revised Krom logic

Kexu Wang, Shiguang Feng, Xishun Zhao

We study the expressive power and complexity of second-order revised Krom logic (SO-KROM). On ordered finite structures, we show that its existential fragment -KROM$^r…

cs.LO2019

A Logic that Captures P on Ordered Structures

Kexu Wang, Xishun Zhao

We extend the inflationary fixed-point logic, IFP, with a new kind of second-order quantifiers which have (poly-)logarithmic bounds. We prove that on ordered structures the new log…

quant-ph2018★ 9 cited

Quantum-enhanced Logic-based Blockchain I: Quantum Honest-success Byzantine Agreement and Qulogicoin

Xin Sun, Quanlong Wang, Piotr Kulicki +1

We proposed a framework of quantum-enhanced logic-based blockchain, which improves the efficiency and power of quantum-secured blockchain. The efficiency is improved by using a new…

cs.DM2016★ 5 cited

Unsatisfiable hitting clause-sets with three more clauses than variables

Oliver Kullmann, Xishun Zhao

The topic of this paper is the Finiteness Conjecture for minimally unsatisfiable clause-sets (MUs), stating that for each fixed deficiency (number of clauses minus number of variab…

cs.DM2015

Parameters for minimal unsatisfiability: Smarandache primitive numbers and full clauses

Oliver Kullmann, Xishun Zhao

We establish a new bridge between propositional logic and elementary number theory. The main objects are "minimally unsatisfiable clause-sets", short "MUs", unsatisfiable conjuncti…

cs.LO2015★ 1 cited

Canonical Logic Programs are Succinctly Incomparable with Propositional Formulas

Yuping Shen, Xishun Zhao

\emph{Canonical (logic) programs} (CP) refer to normal logic programs augmented with connective . In this paper we address the question of whether CP are \emph{succinctly…

math.CO2014★ 8 cited

Bounds for variables with few occurrences in conjunctive normal forms

Oliver Kullmann, Xishun Zhao

We investigate connections between SAT (the propositional satisfiability problem) and combinatorics, around the minimum degree (number of occurrences) of variables in various forms…

cs.DM2012★ 3 cited

On Davis-Putnam reductions for minimally unsatisfiable clause-sets

Oliver Kullmann, Xishun Zhao

For investigations into the structure of MU, i.e., minimally unsatisfiable clause-sets or conjunctive normal forms, singular DP-reduction is a fundamental tool, applying DP-reducti…

cs.AI2011

Proof System for Plan Verification under 0-Approximation Semantics

Xishun Zhao, Yuping Shen

In this paper a proof system is developed for plan verification problems and under 0-approximation semantics for . Here, for a plan $…

cs.DM2010★ 11 cited

On variables with few occurrences in conjunctive normal forms

Oliver Kullmann, Xishun Zhao

We consider the question of the existence of variables with few occurrences in boolean conjunctive normal forms (clause-sets). Let mvd(F) for a clause-set F denote the minimal vari…

cs.LO2010

NP-Logic Systems and Model-Equivalence Reductions

Yuping Shen, Xishun Zhao

In this paper we investigate the existence of model-equivalence reduction between NP-logic systems which are logic systems with model existence problem in NP. It is shown that amon…