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31.
This paper studies the problem of a functionally graded piezoelectric circular plate subjected to a uniform electric potential
difference between the upper and lower surfaces. By assuming the generalized displacements in appropriate forms, five differential
equations governing the generalized displacement functions are derived from the equilibrium equations. These displacement
functions are then obtained in an explicit form, which still involve four undetermined integral constants, through a step-by-step
integration which properly incorporates the boundary conditions at the upper and lower surfaces. The boundary conditions at
the cylindrical surface are then used to determine the integral constants. Hence, three-dimensional analytical solutions for
electrically loaded functionally graded piezoelectric circular plates with free or simply-supported edge are completely determined.
These solutions can account for an arbitrary material variation along the thickness, and thus can be readily degenerated into
those for a homogenous plate. A numerical example is finally given to show the validity of the analysis, and the effect of
material inhomogeneity on the elastic and electric fields is discussed.
Supported by the National Natural Science Foundation of China (Grant Nos. 10472102 and 10432030) and the Specialized Research
Fund for the Doctoral Program of Higher Education of China (Grant No. 20060335107) 相似文献
32.
Salvatore Sessa 《Fuzzy Sets and Systems》1984,13(1):95-100
In this communication, we explicitly point out that the principal results of Liu 1982 basically deduced from the definition of binary operation ° on the set F(X) of all fuzzy subsets of X, also hold if one uses the weaker definition of product under triangular norm °t. Fuzzy ideals with respect to the triangular norms are also defined. 相似文献
33.
Richard D. McBride 《Mathematical Programming》1980,18(1):49-61
A dynamic factorization algorithm is developed which algebraically partitions the basis inverse in such a manner so that the simplex method can be executed from a series of small inverses and the basis itself. This partition is maintained dynamically so that the additional memory required to represent the basis inverse reduces to this series of small inverses for in-core implementations.The algorithm is intended for use in solving general large-scale linear programming problems. This new method of basis representation should permit rather large problems to be solved completely in-core.Preliminary computational experience is presented and comparisons are made with Reid's sparsity-exploiting variant of the Bartels—Golub decomposition for linear programming bases. The computational experience indicated that a significant reduction in memory requirements can usually be obtained using the dynamic factorization approach with only a slight (up to about 20%) degradation of execution time.This research was supported in part by the Air Force Office of Scientific Research, Air Force System Command, USAF, under AFOSR Contract/Grant Number AFOSR-74-2715. 相似文献
34.
35.
The paper studies the dynamic behavior of perfect rigid-plastic plates in the form of a sector with hinged or clamped sides under short-term intensive loads. Two dynamic deformation mechanisms are demonstrated. The dynamic equation is derived for each of the mechanisms. The realization conditions for the mechanisms are analyzed. Analytical expressions are derived for the ultimate (high) loads and the maximum residual deflection. Numerical examples are given 相似文献
36.
Jan Andres Tom Fürst Karel Pastor 《Journal of Mathematical Analysis and Applications》2008,340(2):1132-1144
A full analogy of the celebrated Sharkovsky cycle coexistence theorem is established for lower semicontinuous (multivalued) maps on metrizable linear continua. This result is further extended to triangular maps. 相似文献
37.
On the resolution and optimization of a system of fuzzy relational equations with sup-T composition 总被引:3,自引:2,他引:1
This paper provides a thorough investigation on the resolution of a finite system of fuzzy relational equations with sup-T composition, where T is a continuous triangular norm. When such a system is consistent, although we know that the solution set can be characterized
by a maximum solution and finitely many minimal solutions, it is still a challenging task to find all minimal solutions in
an efficient manner. Using the representation theorem of continuous triangular norms, we show that the systems of sup-T equations can be divided into two categories depending on the involved triangular norm. When the triangular norm is Archimedean,
the minimal solutions correspond one-to-one to the irredundant coverings of a set covering problem. When it is non-Archimedean, they only correspond to a subset of constrained irredundant coverings of a set covering problem. We then show that the problem of minimizing a linear objective function subject to a system of sup-T equations can be reduced into a 0–1 integer programming problem in polynomial time. This work generalizes most, if not all,
known results and provides a unified framework to deal with the problem of resolution and optimization of a system of sup-T equations. Further generalizations and related issues are also included for discussion. 相似文献
38.
In this paper, a new type of bivariate basis on a triangle is presented, which is constructed by extending the univariate NTP basis proposed by Delgado and Peña. Some algebraic properties and its recursive formulae are given. Then a new type of surfaces that is called triangular DP surface is defined, and its recursive evaluation algorithm is obtained. Also, in the case of low degree, its subdivision algorithm and degree elevation algorithm are derived. It is shown that this type of surfaces is obviously more advantageous than triangular Bézier surface, and hence extremely useful for geometric design, especially for the situation in which the surface needs to be evaluated quickly. 相似文献
39.
The second part of this paper deals with the systolic implementation of the computational kernel for factorial data analysis, defined in Part I, on special-purpose hardware. The framework of the study is that a sequence of different algorithms has to be performed on a unique hardware array. This fact has led us to the design of the programmable systolic array SARDA: this is a triangular array which consists of programmable nodes with local memory and programmable orthogonal connections. 相似文献
40.
本文提出了一种用于分析复合材料迭层板弯曲的新方法。首先利用经典理论进行初步分析,之后,据所得横向剪力,设定横向剪切应变,再进一步分析。本文方法基本未知函数少,基本方程易解,计算精度较高。 相似文献