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121.
Rajiv R. Thareja James R. Stewart Obey Hassan Ken Morgan Jaime Peraire 《国际流体数值方法杂志》1989,9(4):405-425
An upwind finite element technique that uses cell-centred quantities and implicit and/or explicit time marching has been developed for computing hypersonic laminar viscous flows using adaptive triangular grids. The approach is an extension to unstructured grids of the LAURA algorithm due to Gnoffo. A structured grid of quadrilaterals is laid out near a solid surface. For inviscid flows the method is stable at Courant numbers of over 100000. A first-order basic scheme and a higher-order flux-corrected transport (FCT) scheme have been implemented. This technique has been applied to the problem of predicting type III and IV shock wave interactions on a cylinder, with a view to simulating the pressure and heating rate augmentation caused by an impinging shock on the leading edge of a cowl lip of an engine inlet. The predictions of wall pressure and heating rates compare very well with experimental data. The flow features are distinctly captured with a sequence of adaptively generated grids. 相似文献
122.
We study the ideal gas of fermions on a lattice at finite density for both naive and Wilson fermions. Comparing the thermodynamical quantities thus calculated with the known results in the continuum theory, we are led to propose a modification of the naive form of the lattice action, which is same for both the naive and the Wilson fermions. The thermodynamical quantities, calculated by using this form, are shown to have the correct continuum limit. 相似文献
123.
A portable bifurcation and stability analysis package, called BISTAB, is described. The package is written in FORTRAN V and can follow the connected set of equilibrium curves for a system of nonlinear ordinary differential equations in the state × parameter space by varying a bifurcation parameter. The curves are traced from an initial point with the continuation method of Kubicek, and the tangent method of Keller is used to find initial points on bifurcating curves near simple bifurcation points. Linearized stability analysis, location of Hopf bifurcation points, and sorting of points for plotting are also supported. While the package contains no new numerical methods, the lack of a requirement for any derivative information higher than the Jacobian makes BISTAB computationally efficient and useful for applied problems where nonnumerical bifurcation analysis may be difficult. 相似文献
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We present an approach to providing broad-based accessibility to graphical applications by employing the capabilities of the
Eclipse platform and aspect-oriented programming (AOP) in a way that leverages the strengths of each. We first describe the
Eclipse platform and the variety of frameworks that can be useful to the effort. We also present the advantages of aspect-oriented
programming and contrast aspect-oriented programming with object-oriented programming (OOP). Then, we discuss how to use the
Eclipse frameworks and AOP in the design of accessible Eclipse-based applications and share some situations of when to leverage
these frameworks and when we do not from the perspective of robustness and efficiency. 相似文献
128.
S. Raman P.H. Stelson G.G. Slaughter J.A. Harvey T.A. Walkiewicz G.J. Lutz L.G. Multhauf K.G. Tirsell 《Nuclear Physics A》1973,206(2):343-352
We have carried out measurements on the decay of 119In isomers and the 118Sn(n, γ) reaction to supplement Coulomb excitation measurements on 119Sn. In addition to the 311.39 keV isomeric transition in 119In, we observed 13 γ-rays in 119Sn from the decay of the 2 min and 18 min 119In isomers. These γ-rays have been incorporated into a level scheme of 119Sn with levels at 0, 23.867, 89.54, 787.01, 920.5, 921.4, 1089.5, 1187.76, 1249.67, 1304.44 and 1354 keV. Conclusive evidence for the existence of a 920.5–921.4 keV, level doublet was obtained from capture γ-ray measurements of resonance energy neutrons. 相似文献
129.
Mathematische Zeitschrift - 相似文献
130.
A mathematical model for the EEG is presented here based on physical and anatomical characteristics of the brain. The important finding is that the system is characterised by a diffusion equation whose general solution represents a Fourier series expansion for the EEG at any point of the zone under consideration. 相似文献