This paper studies the three-term conjugate gradient method for unconstrained optimization. The method includes the classical (two-term) conjugate gradient method and the famous Beale-Powell restart algorithm as its s...
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This paper studies the three-term conjugate gradient method for unconstrained optimization. The method includes the classical (two-term) conjugate gradient method and the famous Beale-Powell restart algorithm as its special forms. Some mild conditions are given in this paper, which ensure the global convergence of general three-term conjugate gradient methods.
Correction methods for the steady semi-periodic motion of incompressible fluid are investigated. The idea is similar to the influence matrix to solve the lack of vorticity boundary conditions. For any given boundary...
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Correction methods for the steady semi-periodic motion of incompressible
fluid are investigated. The idea is similar to the influence matrix to solve the
lack of vorticity boundary conditions. For any given boundary condition of the
vorticity, the coupled vorticity-stream function formulation is solved. Then solve
the governing equations with the correction boundary conditions to improve the
solution. These equations are numerically solved by Fourier series truncation and
finite difference method. The two numerical techniques are employed to treat the non-
linear terms. The first method for small Reynolds number R equals 0-50 has the same
results as that in M. Anwar and S.C.R. Dennis' report. The second one for R greater
than 50 obtains the reliable results. (Author abstract) 4 Refs.
For a class of ideal models of parallel computers, we define some measuring parameters such as the speed-up, the efficiency, the redundancy of a linear and nonlinear parallel iteration method in both average and asymp...
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For a class of ideal models of parallel computers, we define some measuring parameters such as the speed-up, the efficiency, the redundancy of a linear and nonlinear parallel iteration method in both average and asymptotic senses, as well as the utilization ratio of the parallel computer. These parameters are reasonable and convenient for the theoretical studies of the parallel iteration methods.
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