Finite and boundary element approach to process simulation with conjugate gradient-based method

An approach is presented to determine the design that minimizes the weight in consideration of the postbuckling behavior of stiffened composite panels. Since, due to computational expense, for optimization purposes a nonlinear finite element approach is not appropriate, a semianalytical approach is implemented in the EADS MAS software LAGRANGE. A gradient-based optimization scheme is employed to determine the ply thicknesses and fiber orientation of the composite skins and the cross-sectional areas of the stiffeners. Strength and stability constraints are used. Based on two examples of different complexity, weight savings are shown to be due to the fact, that skin buckling is allowed above a certain load level.

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An isogeometric finite element-boundary element approach for the vibration analysis of submerged thin-walled structures

Computers & Structures ◽

10.1016/j.compstruc.2021.106636 ◽

2021 ◽

Vol 256 ◽

pp. 106636

Author(s):

Alvaro del Toro Llorens ◽

Josef Kiendl

Keyword(s):

Finite Element ◽

Boundary Element ◽

Vibration Analysis ◽

Thin Walled Structures ◽

Element Approach ◽

Thin Walled ◽

Element Boundary

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Thermal fracture interference: a two-dimensional boundary element approach

International Journal of Fracture ◽

10.1007/s10704-005-1890-x ◽

2005 ◽

Vol 132 (4) ◽

pp. 351-369 ◽

Cited By ~ 10

Author(s):

G. I. GIANNOPOULOS ◽

N. K. ANIFANTIS

Keyword(s):

Boundary Element ◽

Thermal Fracture ◽

Two Dimensional ◽

Dimensional Boundary ◽

Element Approach

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A Penalized Linear and Nonlinear Combined Conjugate Gradient Method for the Reconstruction of Fluorescence Molecular Tomography

International Journal of Biomedical Imaging ◽

10.1155/2007/84724 ◽

2007 ◽

Vol 2007 ◽

pp. 1-19 ◽

Cited By ~ 1

Author(s):

Shang Shang ◽

Jing Bai ◽

Xiaolei Song ◽

Hongkai Wang ◽

Jaclyn Lau

Keyword(s):

Conjugate Gradient Method ◽

Conjugate Gradient ◽

Gradient Method ◽

Optimization Problems ◽

Gradient Methods ◽

Reconstruction Algorithms ◽

Fluorescence Molecular Tomography ◽

Nonlinear Conjugate Gradient Method ◽

Gradient Based ◽

Linear And Nonlinear

Conjugate gradient method is verified to be efficient for nonlinear optimization problems of large-dimension data. In this paper, a penalized linear and nonlinear combined conjugate gradient method for the reconstruction of fluorescence molecular tomography (FMT) is presented. The algorithm combines the linear conjugate gradient method and the nonlinear conjugate gradient method together based on a restart strategy, in order to take advantage of the two kinds of conjugate gradient methods and compensate for the disadvantages. A quadratic penalty method is adopted to gain a nonnegative constraint and reduce the illposedness of the problem. Simulation studies show that the presented algorithm is accurate, stable, and fast. It has a better performance than the conventional conjugate gradient-based reconstruction algorithms. It offers an effective approach to reconstruct fluorochrome information for FMT.

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