共查询到20条相似文献，搜索用时 31 毫秒
1.
INTRODUCTIONInelasticity ,theproblemofasimplysup portedcircularplatesubjectedtouniformloadsisaclassicone .Timoshenkoetal.(1970 )pre sentedasolutionforanisotropiccircularplate .Dingetal.(2 0 0 0 ;2 0 0 1)obtainedtheanalyti calthree dimensionalsolutionforat… 相似文献
2.
Stress analysis of anisotropic thick laminates in cylindrical bending using a semi-analytical approach 总被引：1，自引：0，他引：1
LU Chao-feng LIM C.W. XU Feng 《浙江大学学报(A卷英文版)》2007,8(11):1740-1745
Semi-analytical elasticity solutions for bending of angle-ply laminates in cylindrical bending are presented using the state-space-based differential quadrature method (SSDQM). Partial differential state equation is derived from the basic equations of elasticity based on the state space concept. Then, the differential quadrature (DQ) technique is introduced to discretize the longitu- dinal domain of the plate so that a series of ordinary differential state equations are obtained at the discrete points. Meanwhile, the edge constrained conditions are handled directly using the stress and displacement components without the Saint-Venant principle. The thickness domain is solved analytically based on the state space formalism along with the continuity conditions at interfaces. The present method is validated by comparing the results to the exact solutions of Pagano’s problem. Numerical results for fully clamped thick laminates are presented, and the influences of ply angle on stress distributions are discussed. 相似文献
3.
Axisymmetric fundamental solutions that are applied in the consolidation calculations of a finitecaly clay layer with impeded
boundaries were derived. Laplace and Hankel integral transforms were utilized with respect to time and radial coordinates,
respectively in the analysis. The derivation of fundamental solutions considers two boundary-value problems involving unit
point loading and ring loading in the vertical. The solutions are extended to circular distributed and strip distributed normal
load. The computation and analysis of settlements, vertical total stress and excess pore pressure in the consolidation layer
subject to circular loading are presented.
Project (No. 500117) supported by the National Natural Science Foundation of Zhejiang Province 相似文献
4.
A bi-harmonic potential function was constructed in this study. Love solution was employed to obtain analytical solutions of uniformly loaded plates with two different types of clamped edges. The treatment of clamped boundary conditions was the same as that adopted by Timoshenko and Goodier （1970）. The analytical solution for the first type of clamped boundary condition is identical with that obtained by Luo et al.（2004）, and the solutions for both types were compared with the FEM results and the calculations of thin plate theory. 相似文献
5.
n-soliton-like solutions of three non-isospectral equations, the non-isospectral mKdV equation, the non-isospectral sine-Gordon equation and the non-isospeetral nonlinear Schroedinger equation were obtained by using the Hirota method. 相似文献
6.
This paper aims to investigate exact solutions for a second-grade fluid flow with the inverse method. By assuming the relation
between the vorticity field and the streamfunction, the exact solutions of the motion of plane second-grade fluids are investigated
and obtained. The solutions obtained include simple Couette flows, slit jet flows and uniform flows over a series of distributed
obstacles.
Project supported by the National Natural Science Foundation of China (Grant No.10472063) 相似文献
7.
General solutions for coupled three dimensional equations of piezoelectric media were used in this work to obtain some analytical
solutions for free vibration of piezoelectric annular plates. These solutions not only satisfy the governing equations at
every point in the concerned region but also satisfy the prescribed boundary conditions at every point on the boundaries.
Therefore, they are three-dimensional exact. Numerical results are finally tabulated.
Project (No. 10002016) supported by the National Natural Science Foundation of China 相似文献
8.
A three-dimensional, exact analysis is presented in this paper for the problem of an external circular crack in a transversely
isotropic piezoelectric medium subjected to arbitrary antisymmetric shear loading. A recently proposed general solution of
three-dimensional piezoelectricity is employed. It is shown that four quasi harmonic functions involved in the general solution
can be respresented by just one complex potential. Previous results in potential theory are then used to obtain the exact
solution of the problem. For point shear loading, Green’s functions for the elastoelectric field are derived in terms of elementary
functions.
Project supported by Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry and partly
by National Natural Science Foundation of China (NSFC) (10002016). 相似文献
9.
The bilinear Baecklund transformation (BT) provides a means of finding multisoliton solutions of some non-linear evolution equations, where Hirota‘s technique is used. In this paper, the bilinear BT for Toda lattice was modified and then some novel solutions of the Toda lattice was constructed through the modified BT. 相似文献
10.
Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed
by intramolecular cyclization of 1,1-dicyanoalkenes under mild conditions.
Preject (No. 20072033) supported by the National Natural Science Foundation of China, and Zhejiang Provincial Natural Science
Foundation of China 相似文献
11.
Study of the SISO mixedH
2/l1 problem for discrete time systems showed that there exists a unique optimal solution which can be approximated within any
prescribed missing error bound inl
2 norm with solvable suboptimal solutions and solvable superoptimal solutions.
Project supported by the National Natural Science Foundation of China (No. 60174026) and the Scientific Research Foundation
for Returned Overseas Chinese Scholars of Zhejiang Province (No. J20020546) 相似文献
12.
This paper proposes novel multi-layer neural networks based on Independent Component Analysis for feature extraction of fault
modes. By the use of ICA, invariable features embedded in multi-channel vibration measurements under different operating conditions
(rotating speed and/or load) can be captured together. Thus, stable MLP classifiers insensitive to the variation of operation
conditions are constructed. The successful results achieved by selected experiments indicate great potential of ICA in health
condition monitoring of rotating machines.
Project supported by the National Natural Science Foundation (No. 50205025) and the Natural Science Foundation of Zhejiang
Province (No. 5001004). 相似文献
13.
The thermal behavior of a thick transversely isotropic FGM rectangular plate was investigated within the scope of three-dimensional
elasticity. Noticing many FGMs may have temperature-dependent properties, the material constants were further considered as
functions of temperature. A solution method based on state-space formulations with a laminate approximate model was proposed.
For a thin plate, the method was clarified by comparison with the thin plate theory. The influences of material inhomogeneity
and temperature-dependent characteristics were finally discussed, through numerical examples.
Project (No. 10002016) supported by National Natural Science Foundation of China 相似文献
14.
Texture classification based on EMD and FFT 总被引：2，自引：0，他引：2
XIONG Chang-zhen XU Jun-yi ZOU Jian-cheng QI Dong-xu 《浙江大学学报(A卷英文版)》2006,7(9):1516-1521
INTRODUCTION Multi-scale is one of the main features of natural images, a series of methods for representing the quality of images are presented, such as multi-scale technique based on diffusion equation (Perona and Malik, 1990), image pyramid (Burt and Adelson, 1983) and wavelet (Mallat, 1989). Bidimensional empirical mode decomposition (BEMD) (Nunes et al., 2005; Linderhed, 2004) is a new multi-scale analysis method proposed recently. The difference between BEMD and traditional mul… 相似文献
15.
In this paper, dynamics in the oscillations of the relative atomic population in two periodically driven and weakly coupled Bose-Einstein eondensates (BECs) was qualitatively studied. Using the well-known Melnikov method, the conditions of existence of the periodic and chaotic coherent atomic tunnellings were given in the model. Our results indicate the typical route from bifurcation of the limited circles to chaos, and are in agreement with the previous numerical results. 相似文献
16.
Stabilization for a class of second-order switched systems with saturation constrains 总被引：1，自引：0，他引：1
This paper proposes a global stabilization method for a class of planar switched systems with input saturation constrains
by using a state feedback and switching strategy. This method is proved to be effective by analyzing the characteristics of
the trajectory of second-order linear systems with input saturation.
Project supported by the China Postdoctoral Science Foundation (Grant No.20070420643), the National Natural Science Foundation
of China (Grant No.60774059), and the Innovation Program of the Shanghai Municipal Science and Technology Commission (Grant
No.08DZ2272400) 相似文献
17.
李明忠 《上海大学学报(英文版)》1999,3(2):95-99
Nonlinear boundary problem for a class of the first order elliptic partial differential system with the general form are studied
in this paper. And the equivalent nonlinear singular integral equations are established. Then the existence theorem of solution
of the problem are also obtained.
Project supported by the National Natural Science Foundation of China (19671056) 相似文献
18.
用于通信的超宽带印刷天线 总被引：1，自引：1，他引：1
1IntroductionUltra-wideband(UWB)microwave antennas are ofinterest for a variety of applications such as electroniccountermeasure,transient radars,mine detection,andunexploded ordnance(UXO)location and identifica-tion.In the early2002,the release of the UWB forcommercial communications by the Federal Communi-cation Commission(FCC,USA)sparked renewed in-terest in the subject of UWB antennas.Conventional UWB antennas such as log-periodic orspiral antennas exhibit good UWB characteristi… 相似文献
19.
INTRODUCTION General solution is a convenient, effective method for solving space problems such as problems of infinite, semi-infinite and two-phase infinite media. For linear theory of piezoelasticity, Ding et al.(1996; 1997a) gave the general solution for coupled equa-tions for transversely piezoelectric media using po-tential theory. Ding et al.(1997b; 1997c) gave the general solution of plane problem. Based on the gen-eral solution, Ding et al.(1997a) presented the closed form fundam… 相似文献
20.
Nonlinear dynamics analysis of a new autonomous chaotic system 总被引：2，自引：0，他引：2
CHU Yan-dong LI Xian-feng ZHANG Jian-gang CHANG Ying-xiang 《浙江大学学报(A卷英文版)》2007,8(9):1408-1413
In this paper,a new nonlinear autonomous system introduced by Chlouverakis and Sprott is studied further,to present very rich and complex nonlinear dynamical behaviors. Some basic dynamical properties are studied either analytically or nu-merically,such as Poincaré map,Lyapunov exponents and Lyapunov dimension. Based on this flow,a new almost-Hamilton chaotic system with very high Lyapunov dimensions is constructed and investigated. Two new nonlinear autonomous systems can be changed into one another by adding or omitting some constant coefficients. 相似文献