A Hybrid ACO Approach to the Matrix Bandwidth Minimization Problem

We propose a simple and direct node shifting method with hill climbing for the well-known matrix bandwidth minimization problem. Many heuristics have been developed for this NP-complete problem including the Cuthill-McKee (CM) and the Gibbs, Poole and Stockmeyer (GPS) algorithms. Recently, heuristics such as Simulated Annealing, Tabu Search and GRASP have been used, where Tabu Search and the GRASP with Path Relinking achieved significantly better solution quality than the CM and GPS algorithms. Experimentation shows that our method achieves the best solution quality when compared with these while being much faster than newly-developed algorithms.

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Concise Equations for Rotor Dynamics Analysis

Volume 3B: 15th Biennial Conference on Mechanical Vibration and Noise — Acoustics, Vibrations, and Rotating Machines ◽

10.1115/detc1995-0489 ◽

1995 ◽

Author(s):

W. J. Chen

Keyword(s):

Equations Of Motion ◽

Rotor Dynamics ◽

Memory Storage ◽

The Other ◽

Dynamics Analysis ◽

Real Domain ◽

The Matrix ◽

System Equations ◽

Ordering Algorithms ◽

Matrix Bandwidth

Abstract Concise equations for rotor dynamics analysis are presented. Two coordinate ordering methods are introduced in the element equations of motion. One is in the real domain and the other is in the complex domain. The two proposed ordering algorithms lead to more compact element matrices. A station numbering technique is also proposed for the system equations during the assembly process. This numbering technique can minimize the matrix bandwidth, the memory storage and can increase the computational efficiency.

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A Note on Computational Rotor Dynamics

Journal of Vibration and Acoustics ◽

10.1115/1.2893810 ◽

1998 ◽

Vol 120 (1) ◽

pp. 228-233 ◽

Cited By ~ 2

Author(s):

W. J. Chen

Keyword(s):

Computational Efficiency ◽

Equations Of Motion ◽

Rotor Dynamics ◽

Memory Storage ◽

Rotor Systems ◽

Real Domain ◽

The Matrix ◽

System Equations ◽

Ordering Algorithms ◽

Matrix Bandwidth

Concise equations for improvements in computational efficiency on dynamics of rotor systems are presented. Two coordinate ordering methods are introduced in the element equations of motion. One is in the real domain and the other is in the complex domain. The two coordinate ordering algorithms lead to compact element matrices. A station numbering technique is also proposed for the system equations during the assembly process. The proposed numbering technique can minimize the matrix bandwidth, the memory storage and can increase the computational efficiency. Numerical examples are presented to demonstrate the benefit of the proposed algorithms.

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A centroid-based approach to solve the bandwidth minimization problem

37th Annual Hawaii International Conference on System Sciences, 2004. Proceedings of the ◽

10.1109/hicss.2004.1265221 ◽

2004 ◽

Cited By ~ 6

Author(s):

A. Lim ◽

B. Rodrigues ◽

Fei Xiao

Keyword(s):

Minimization Problem ◽

Bandwidth Minimization

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Numerical Analysis of Turbine Coolant Passage Flows

Volume 4: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/98-gt-320 ◽

1998 ◽

Author(s):

Meng-Sing Liou ◽

K. P. Singh

Keyword(s):

Iterative Scheme ◽

Three Dimensional ◽

Nasa Lewis Research ◽

Reynolds Stresses ◽

Complex Flow ◽

Internal Flows ◽

The Matrix ◽

Turbine Component ◽

Unstructured Tetrahedral Meshes ◽

Matrix Bandwidth

We report in this paper a project undertaken at NASA Lewis Research Center with an aim at achieving a timely, reliable, and high-fidelity CFD prediction of aeropropulsion systems. The present paper specifically addresses issues relevant to internal flows in a turbine component. The flows are three dimensional, highly viscous and turbulent and the geometry is complex. We choose to discretize the computation domain with unstructured tetrahedral meshes and approximate the inviscid fluxes with the recent upwind scheme, AUSM+. An implicit discrete system of unknowns is solved by the Gauss-Seidel Jacobi iterative scheme with a coloring strategy to reduce the matrix bandwidth. A one-equation turbulence model is used to represent the Reynolds stresses. To calculate the complex flow in a turbine coolant passage, we first validate the code for unit problems that contain some subset features. The calculations show excellent results for the backward-facing step and the 180-degree-turn duct. Finally we provide a detailed analysis of the flow in the simulated geometry of th turbine coolant passage.

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