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191.
The existence and uniqueness of solutions to backward stochastic differential equations with jumps and with unbounded stopping time as terminal under the non-Lipschitz condition are obtained. The convergence of solutions and the continuous dependence of solutions on parameters are also derived. Then the probabilistic interpretation of solutions to some kinds of quasi-linear elliptic type integro-differential equations is obtained. Foundation item: the National Natural Science Foundation of China (79790130); the Foundation of Zhongshan University Front Research Biography: Situ Rong (1935 −)  相似文献   
192.
193.
IntroductionAsweknow ,intheinvestigationofthepropertiesofsolutionsfornonlineardifferentialequations,themethodofvariationofparametersisaneffectivetoolinthecasethatthecorrespondingunperturbedtermsarelinearorofcertainsmoothnessthoughtheyarenonlinear.Onthe…  相似文献   
194.
Based on elasto-plasticity and damage mechanics, a double-medium constitutive model of geological material under uniaxial tension and compression was presented, on the assumption that rock and soil materials are the pore-fracture double-medium, and porous medium has no damage occurring, while fracture medium has damage occurring with load. To the implicit equation of the model, iterative method was adopted to obtain the complete stress-strain curve of the material. The result shows that many different distributions (uniform distribution, concentrated distribution and random distribution) of fractures in rock and soil material are the essential reasons of the daedal constitutive relations. By the reason that the double-medium constitutive model separates the material to be porous medium part, which is the main body of elasticity, and fracture medium part, which is the main body of damage, it is of important practical values and theoretical meanings to the study on failure of rock and soil or materials containing damage.  相似文献   
195.
Stair matrices and their generalizations are introduced. The definitions and some properties of the matrices were first given by Lu Hao. This class of matrices provide bases of matrix splittings for iterative methods. The remarkable feature of iterative methods based on the new class of matrices is that the methods are easily implemented for parallel computation. In particular, a generalization of the accelerated overrelaxation method (GAOR) is introduced. Some theories of the AOR method are extended to the generalized method to include a wide class of matrices. The convergence of the new method is derived for Hermitian positive definite matrices. Finally, some examples are given in order to show the superiority of the new method.  相似文献   
196.
NOVEL REGULARIZED BOUNDARY INTEGRAL EQUATIONS FOR POTENTIAL PLANE PROBLEMS   总被引:3,自引:0,他引:3  
The universal practices have been centralizing on the research of regulariza-tion to the direct boundary integal equations (DBIEs). The character is elimination of singularities by using the simple solutions. However, up to now the research of regular ization to the first kind integral equations for plane potential problems has never been found in previous literatures. The presentation is mainly devoted to the research on the regularization of the singular boundary integral equations with indirect unknowns. A novel view and idea is presented herein, in which the regularized boundary integral equations with indirect unknowns without including the Cauchy principal value (CPV) and Hadamard-finite-part (HFP) integrals are established for the plane potential problems. With some numerical results, it is shown that the better accuracy and higher efficiency, especially on the boundary, can be achieved by the present system.  相似文献   
197.
IntroductionTheelastichalf_spacetheoryoffoundationvibrationandthestudyofsoil_structureinteractionproblemhavebeenthesubjectofintensiveresearchinthecivilengineering .SinceLucoetal.[1]summarizedthevibrationofacircularrigidfoundationrestingonanelastichalf_s…  相似文献   
198.
IntroductionThestudyofrandomparametricexcitedsystemsaremoreimportantthanthatofrandomexternalexcitedones,andaretheoreticallymoredifficultespeciallywhentheexcitationsarenarrow_bandrandomprocesses[1].Inthecasewhenthesystemsareexcitedbycombineddeterministi…  相似文献   
199.
IntroductionItiswell_knownthatpiezoelectricmaterialsproduceanelectricfieldwhendeformedandundergodeformationwhensubjectedtoanelectricfield .Thecouplingnatureofpiezoelectricmaterialshasattractedwideapplicationsinelectric_mechanicalandelectricdevices,suc…  相似文献   
200.
KUHN-TUCKER CONDITION AND WOLFE DUALITY OF PREINVEX SET-VALUED OPTIMIZATION   总被引:1,自引:0,他引:1  
The optimality Kuhn-Tucker condition and the wolfe duality for the prein-vex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function were introduced, from which the properties of the corresponding contingent cone and the alpha-order contingent derivative were studied. Finally, the optimality Kuhn-Tucker condition and the Wolfe duality theorem for the alpha-order S-preinvex set-valued optimization were presented with the help of the alpha-order contingent derivative.  相似文献   
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