Tree precedence in scheduling: The strong-weak distinction

Moshe Dror, W. Kubiak, J. Y T Leung

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In this paper we formally introduce the distinction between strong and weak precedence relation in scheduling for the case of trees. We demonstrate that this distinction in precedence relation for trees (as demonstrated in earlier work for chains) is a proper one in the sense that some problems are solvable in polynomial time if weak tree relation is assumed and are NP-hard in the case of strong tree relations. For some other problems, both weak tree and strong tree relations are NP-hard, and for yet other problems both weak and strong tree relations are polynomially solvable. Since the distinction between strong and weak tree precedence was not clearly recognized in the past, this work establishes the existence of new problem categories in scheduling.

Original languageEnglish (US)
Pages (from-to)127-134
Number of pages8
JournalInformation Processing Letters
Volume71
Issue number3
DOIs
StatePublished - Aug 27 1999

Fingerprint

Scheduling
Polynomials
NP-complete problem
Polynomial time
Demonstrate

ASJC Scopus subject areas

  • Computational Theory and Mathematics

Cite this

Tree precedence in scheduling : The strong-weak distinction. / Dror, Moshe; Kubiak, W.; Leung, J. Y T.

In: Information Processing Letters, Vol. 71, No. 3, 27.08.1999, p. 127-134.

Research output: Contribution to journalArticle

Dror, Moshe ; Kubiak, W. ; Leung, J. Y T. / Tree precedence in scheduling : The strong-weak distinction. In: Information Processing Letters. 1999 ; Vol. 71, No. 3. pp. 127-134.
@article{5bea14b4f25743ec811211519fc2a8b1,
title = "Tree precedence in scheduling: The strong-weak distinction",
abstract = "In this paper we formally introduce the distinction between strong and weak precedence relation in scheduling for the case of trees. We demonstrate that this distinction in precedence relation for trees (as demonstrated in earlier work for chains) is a proper one in the sense that some problems are solvable in polynomial time if weak tree relation is assumed and are NP-hard in the case of strong tree relations. For some other problems, both weak tree and strong tree relations are NP-hard, and for yet other problems both weak and strong tree relations are polynomially solvable. Since the distinction between strong and weak tree precedence was not clearly recognized in the past, this work establishes the existence of new problem categories in scheduling.",
author = "Moshe Dror and W. Kubiak and Leung, {J. Y T}",
year = "1999",
month = "8",
day = "27",
doi = "10.1016/S0020-0190(99)00103-9",
language = "English (US)",
volume = "71",
pages = "127--134",
journal = "Information Processing Letters",
issn = "0020-0190",
publisher = "Elsevier",
number = "3",

}

TY - JOUR

T1 - Tree precedence in scheduling

T2 - The strong-weak distinction

AU - Dror, Moshe

AU - Kubiak, W.

AU - Leung, J. Y T

PY - 1999/8/27

Y1 - 1999/8/27

N2 - In this paper we formally introduce the distinction between strong and weak precedence relation in scheduling for the case of trees. We demonstrate that this distinction in precedence relation for trees (as demonstrated in earlier work for chains) is a proper one in the sense that some problems are solvable in polynomial time if weak tree relation is assumed and are NP-hard in the case of strong tree relations. For some other problems, both weak tree and strong tree relations are NP-hard, and for yet other problems both weak and strong tree relations are polynomially solvable. Since the distinction between strong and weak tree precedence was not clearly recognized in the past, this work establishes the existence of new problem categories in scheduling.

AB - In this paper we formally introduce the distinction between strong and weak precedence relation in scheduling for the case of trees. We demonstrate that this distinction in precedence relation for trees (as demonstrated in earlier work for chains) is a proper one in the sense that some problems are solvable in polynomial time if weak tree relation is assumed and are NP-hard in the case of strong tree relations. For some other problems, both weak tree and strong tree relations are NP-hard, and for yet other problems both weak and strong tree relations are polynomially solvable. Since the distinction between strong and weak tree precedence was not clearly recognized in the past, this work establishes the existence of new problem categories in scheduling.

UR - http://www.scopus.com/inward/record.url?scp=0033609580&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033609580&partnerID=8YFLogxK

U2 - 10.1016/S0020-0190(99)00103-9

DO - 10.1016/S0020-0190(99)00103-9

M3 - Article

AN - SCOPUS:0033609580

VL - 71

SP - 127

EP - 134

JO - Information Processing Letters

JF - Information Processing Letters

SN - 0020-0190

IS - 3

ER -