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991.
提出制造商零售商系统在模糊需求环境下订货量、批发价在合作与非合作情况下的最优解问题.引入采用LR型模糊数符号距离的求解的方法.提出LR型模糊数形式运算的计算方法,并指出在所论问题中LR型模糊数对形式运算的封闭性,提出最优解求解的步骤并编制计算机程序以用于实际计算.举出实例,得出最优订货量为634件的结论.  相似文献   
992.
杨继生 《大学化学》2010,25(5):39-41
探讨在精细化工教学中提高学生综合素质和创新能力的实践方法。通过多媒体综合教学平台的开发与使用,调动学生的创作热情,激发学生的创新意识。举例说明了综合性和设计型实验的实施过程,并强调了学生关注科技发展和信息调研能力培养的必要性。  相似文献   
993.
NONLINEAR EVOLUTION SYSTEMS AND GREEN’S FUNCTION   总被引:1,自引:1,他引:0  
In this paper, we will introduce how to apply Green’s function method to get the pointwise estimates for the solutions of Cauchy problem of nonlinear evolution equations with dissipative structure. First of all, we introduce the pointwise estimates of the time-asymptotic shape of the solutions of the isentropic Navier-Stokes equations and show to exhibit the generalized Huygen’s principle. Then, for other nonlinear dissipative evolution equations, we will only introduce the result and give some brief explanations. Our approach is based on the detailed analysis of the Green’s function of the linearized system and micro-local analysis, such as frequency decomposition and so on.  相似文献   
994.
本文利用拓扑度方法建立一个非自包含不动点定理,并利用它们对一类非线性(连续型)投入产出方程加以研究,得到相应的存在性与连续性结果.  相似文献   
995.
The aim of the paper is to propose an iterative regularization method of proximal point type for finding a common solution for a finite family of inverse-strongly monotone equations in Hilbert spaces.  相似文献   
996.
997.
张文  段梦兰  陈凯 《力学季刊》2011,(3):353-359
S型铺管是一种效率很高的铺设海底管道的方法,研究深水S型铺设管道形态及力学分析方法对于开发我国南海油气田具有重大意义.本文建立了深水S型铺管中管道形态的大挠度梁微分方程,并且通过数值方法求解得到的结果论证了深水S型铺管中管道悬垂段形态可以用自然悬链线近似,并在接下来的对S型铺管中管道的整体力学特性的有限元分析中,对过弯...  相似文献   
998.
Divergence-free wavelets are successfully applied to numerical solutions of Navier-Stokes equation and to analysis of incompressible flows. They closely depend on a pair of one-dimensional wavelets with some differential relations. In this paper, we point out some restrictions of those wavelets and study scaling functions with the differential relation; Wavelets and their duals are discussed; In addition to the differential relation, we are particularly interested in a class of examples with the interpolatory property; It turns out there is a connection between our examples and Micchelli’s work.  相似文献   
999.
This paper focuses on theoretical and experimental investigations of planar nonlinear vibrations and chaotic dynamics of an L-shape beam structure subjected to fundamental harmonic excitation,which is composed of two beams with right-angled L-shape.The ordinary differential governing equation of motion for the L-shape beam structure with two-degree-of-freedom is firstly derived by applying the substructure synthesis method and the Lagrangian equation.Then,the method of multiple scales is utilized to obtain a four-dimensional averaged equation of the L-shape beam structure.Numerical simulations,based on the mathematical model,are presented to analyze the nonlinear responses and chaotic dynamics of the L-shape beam structure.The bifurcation diagram,phase portrait,amplitude spectrum and Poincare map are plotted to illustrate the periodic and chaotic motions of the L-shape beam structure.The existence of the Shilnikov type multi-pulse chaotic motion is also observed from the numerical results.Furthermore, experimental investigations of the L-shape beam structure are performed,and there is a qualitative agreement between the numerical and experimental results.It is also shown that out-of-plane motion may appear intuitively.  相似文献   
1000.
Effects of deposition layer position film are systematically investigated. Because the and number/density on local bending of a thin deposition layer interacts with the thin film at the interface and there is an offset between the thin film neutral surface and the interface, the deposition layer generates not only axial stress but also bending moment. The bending moment induces an instant out-of-plane deflection of the thin film, which may or may not cause the socalled local bending. The deposition layer is modeled as a local stressor, whose location and density are demonstrated to be vital to the occurrence of local bending. The thin film rests on a viscous layer, which is governed by the Navier-Stokes equation and behaves like an elastic foundation to exert transverse forces on the thin film. The unknown feature of the axial constraint force makes the governing equation highly nonlinear even for the small deflection chse. The constraint force and film transverse deflection are solved iteratively through the governing equation and the displacement constraint equation of immovable edges. This research shows that in some special cases, the deposition density increase does not necessarily reduce the local bending. By comparing the thin film deflections of different deposition numbers and positions, we also present the guideline of strengthening or suppressing the local bending.  相似文献   
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