By Topic

A Lagrangian relaxation approach to job shop scheduling problems

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
D. J. Hoitomt ; Pratt & Whitney, E. Hartford, CT, USA ; P. B. Luh ; K. R. Pattipati

An exploration is made of the use of Lagrangian relaxation to schedule job shops, which include multiple machine types, generic precedence constraint, and simple routing considerations. From an augmented Lagrangian formulation, a decomposed solution methodology is developed using a Jacobi-type iterative approach. The subgradient method and the multiplier method are used to update the multipliers and the penalty coefficients. The dual solution forms the basis of a list scheduling algorithm which generates a feasible schedule. Unfortunately, the dual cost is not a lower bound on the optimal cost because of the Jacobi iterative technique employed. In order to evaluate the schedule, a second problem formulation is adopted. Its solution would ordinarily require prohibitive memory and considerable computation time. By utilizing part of the multipliers obtained from the first problem formulation, however, an effective lower bound on the optimal cost can be quickly obtained. A numerical example is given in which schedule cost is within 2% of its lower bound

Published in:

Robotics and Automation, 1990. Proceedings., 1990 IEEE International Conference on

Date of Conference:

13-18 May 1990