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Book Review     
Books reviewed:
Ira A. Jackson and Jane Nelson, Profits with Principles: Seven Strategies for Delivering Values with Values .  相似文献   
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From the principle of of the Domain Decomposition Method (DDM), we analyse the 2nd-order linear elliptic partial differential problems and link the Separated-Layers Algorithm (SLA) with DDM. The mathematical properties of SLA and numerical example are presented to obtain satisfactory computation results. For general linear differential ones, also are the structure of SLA and its characteristics discussed.  相似文献   
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China' s foreign-oriented oil taxation system has, from the beginning, been based upon the positive experiences of other oil-producing countries and has incorporated common international practices. The system has been perfected over decades. It of fers more incentives than other oil-producing countries in the following four aspects: (1) Income tax has a "wide tax base and low tax rate"; (2) VAT levies a low tax rate on ma-  相似文献   
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A finite-difference Total Variation Diminishing (TVD) numerical simulation model for coupling the Reynolds Averaged Navier-Stokes (RANS) equations, pressure-relative continuity equation and various k-εturbulence models was developed to solve the incompressible flow based on the pseudo-compressibility method. The hyperbolicity of all these equations was studied and the discretization of the fully coupling equations with all the primal variables and source terms were made in this article. Numerical simulation for modeling the flow around a ground-mounted square rib was implemented and validated by comparing with the published wind tunnel experimental data. It is shown that such a numerical simulation method with a proper turbulence model has a very good accuracy to simulate the flow around a surface-mounted rib. It is concluded that the Renormalization Group (RNG) and Chen-Kim k-εturbulence models have much better ability to predict the characteristics of the vortex structure and flow separation than the standard k-εmodel.  相似文献   
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This study condiders spatially developing free shear layers at moderateReynolds numbers that are formed by the merging of two free streams initially separatedby a splitter plate.To study the nonlinear interactions between the two-and three-dimen-sional fundamental and subharmonic modes in the spatially developing shear layer,the se-lected five modes represent the minimum number that needs to be considered.The objec-tive of this study is to investigate the nonlinear effects arising from the interactions be-tween two-and three-dimensional large-scale coherent structures in a free shear layer.Our attention is focused on the energy exchange mechanisms between the various modes,and the effects of the nonlinear evolution of the phases of the interacting modes.It isshown that depending on the initial modal phase angles the downstream growth of theshear layer and the associated local entrainment can be strongly affected by the presence ofthese nonlinear interactions.This high sensitivity of the shear layer growt  相似文献   
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In this paper,the oscillation amplitude of the free end of a group of threecylinders are studied.The three cylinders are erected at the vertices of an equilateral trian-gle,and three arrangements are made in this study.One of the three cylinders is served asa working cylinder which is mounted by a flexible cantilever and two accelerometers areattached on the free end in two directions.The results of the three-cylinder arrangementare compared with those of two cylinders in tandem/side-by-side arrangement in the samecondition.The experimental results show that the rear cylinder of a group of three cylin-ders is affected more seriously than that of the corresponding two cylinders in the contrastarrangement.The main direction of oscillation is changed.The transversal oscillation isstronger than the longitudinal oscillation in the three-cylinder arrangement.On the con-trary,the transversal oscillation is much weaker than the longitudinal oscillation in two-cylinder arrangement.The largest transversal oscillat  相似文献   
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As an important cornerstone, the methodology of normal modal analysis plays a quite important role in dynamic analyses of linear vibrating systems, and makes much easy to access an understanding of frequency-domain characteristics of the systems. However, most reported work on fluid-structure interaction (FSI) in liquid-filled pipes has been directly carried out in the time domain. When needed, information in the frequency domain has been deduced by the discrete Fourier transforms. In this paper, an analysis is undertaken directly to get modal information of FSI in internal flows and has the advantage of enabling dispersive and dissipative terms to be included in a fully coupled manner. The development used herein highlights common features of the analysis in the frequency domain. The method is validated by comparison with an exact analytical solution, with the results obtained by the discrete Fourier transform from an analysis using the method of characteristics and by comparison with measured data fr  相似文献   
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