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An Improved Algorithm for a Bicriteria Batching Scheduling Problem

Cheng He, Xiumei Wang, Yixun Lin, Yundong Mu (2013)

RAIRO - Operations Research - Recherche Opérationnelle

This note is concerned with the bicriteria scheduling problem on a series-batching machine to minimize maximum cost and makespan. An O(n5) algorithm has been established previously. Here is an improved algorithm which solves the problem in O(n3) time.

An improved ant algorithm for Multi-mode Resource Constrained Project Scheduling Problem

Peng Wuliang, Huang Min, Hao Yongping (2014)

RAIRO - Operations Research - Recherche Opérationnelle

Many real-world scheduling problems can be modeled as Multi-mode Resource Constrained Project Scheduling Problems (MRCPSP). However, the MRCPSP is a strong NP-hard problem and very difficult to be solved. The purpose of this research is to investigate a more efficient alternative based on ant algorithm to solve MRCPSP. To enhance the generality along with efficiency of the algorithm, the rule pool is designed to manage numerous priority rules for MRCPSP. Each ant is provided with an independent...

An improved nonmonotone adaptive trust region method

Yanqin Xue, Hongwei Liu, Zexian Liu (2019)

Applications of Mathematics

Trust region methods are a class of effective iterative schemes in numerical optimization. In this paper, a new improved nonmonotone adaptive trust region method for solving unconstrained optimization problems is proposed. We construct an approximate model where the approximation to Hessian matrix is updated by the scaled memoryless BFGS update formula, and incorporate a nonmonotone technique with the new proposed adaptive trust region radius. The new ratio to adjusting the next trust region radius...

An infinite horizon predictive control algorithm based on multivariable input-output models

Maciej Ławryńczuk, Piotr Tatjewski (2004)

International Journal of Applied Mathematics and Computer Science

In this paper an infinite horizon predictive control algorithm, for which closed loop stability is guaranteed, is developed in the framework of multivariable linear input-output models. The original infinite dimensional optimisation problem is transformed into a finite dimensional one with a penalty term. In the unconstrained case the stabilising control law, using a numerically reliable SVD decomposition, is derived as an analytical formula, calculated off-line. Considering constraints needs solving...

An instantaneous semi-Lagrangian approach for boundary control of a melting problem

Youness Mezzan, Moulay Hicham Tber (2021)

Applications of Mathematics

In this paper, a sub-optimal boundary control strategy for a free boundary problem is investigated. The model is described by a non-smooth convection-diffusion equation. The control problem is addressed by an instantaneous strategy based on the characteristics method. The resulting time independent control problems are formulated as function space optimization problems with complementarity constraints. At each time step, the existence of an optimal solution is proved and first-order optimality conditions...

An interior point algorithm for convex quadratic programming with strict equilibrium constraints

Rachid Benouahboun, Abdelatif Mansouri (2005)

RAIRO - Operations Research - Recherche Opérationnelle

We describe an interior point algorithm for convex quadratic problem with a strict complementarity constraints. We show that under some assumptions the approach requires a total of O ( n L ) number of iterations, where L is the input size of the problem. The algorithm generates a sequence of problems, each of which is approximately solved by Newton’s method.

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