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251.
本文的第二作者在近几年发展了一种守恒型的间断跟踪法,该跟踪法是以解的守恒性质作为跟踪的机制,而不是象传统的跟踪法利用Rankine-Hugoniot条件来进行跟踪.本文中主要研究将该算法推广至单个守恒律非凸流的情况.利用精确求解Riemann问题,我们很好地处理了非凸流Riemann解的激波和稀疏波的并存结构,既实现了对激波的跟踪,又成功地分辨出稀疏波.第四节的数值例子。显示了满意的数值结果. 相似文献
252.
The purpose of this paper is to prove existence of minimisers of the functional J(K,u):=∫Ω\K f(Lu)dx α∫Ω\K |u - g|qdx βSQ-1d(K∩Ω),where Ω is an open set of the Heisenberg group Hn, K runs over all closed sets of Hn, u varies in C1H(Ω\K), α,β>0,q ≥ 1,g ∈ Lq(Ω) ∩L∞(Ω) and f: R2n → R is a convex function satisfying some structure conditions (H1)(H2)(H3) (see below). 相似文献
253.
In this paper we propose a variational model for the irreversible quasi static growth in brittle fractures for a linearly
elastic homogeneous isotropic plate, subject to a time dependent vertical displacement on a part of its lateral surface. The
model is based on the Griffith’s criterion for crack growth and is inspired to the model proposed in [11] by Francfort and
Marigo in the case of 3-D elasticity. We give a precise mathematical formulation of the model and in this framework we prove
an existence result.
Mathematics Subject Classification (2000) 74K20, 35J35, 74G65, 35R35, 35A35, 74R10 相似文献
254.
We study the Cauchy problem for the isentropic 2-D Euler system with initial data having discontinuity on a smooth curve. A local existence of a solution is established, which consists of shock wave, rarefaction wave and contact discontinuity. 相似文献
255.
实验研究了存在蒸发界面的水平液层中的热毛细对流对汽/液界面处温度不连续的影响.对于单纯的热毛细对流从理论和实验已有深入研究,但目前国际对蒸发与热毛细对流的耦合尚缺乏研究.特别是近期C.A.Ward等人研究发现了蒸发汽液界面处的温度不连续现象.本文以存在蒸发界面的水平薄液层为研究对象,测量了蒸发界面处的温度分布,研究了普... 相似文献
256.
Zhi-Qiang Shao 《Journal of Mathematical Analysis and Applications》2011,379(2):589-720
This work is a continuation of our previous work, in the present paper we study the generalized nonlinear initial-boundary Riemann problem with small BV data for linearly degenerate quasilinear hyperbolic systems of conservation laws with nonlinear boundary conditions in a half space . We prove the global existence and uniqueness of piecewise C1 solution containing only contact discontinuities to a class of the generalized nonlinear initial-boundary Riemann problem, which can be regarded as a small BV perturbation of the corresponding nonlinear initial-boundary Riemann problem, for general n×n linearly degenerate quasilinear hyperbolic system of conservation laws; moreover, this solution has a global structure similar to the one of the self-similar solution to the corresponding nonlinear initial-boundary Riemann problem. Some applications to quasilinear hyperbolic systems of conservation laws arising in the string theory and high energy physics are also given. 相似文献
257.
This paper is concerned with the vanishing capillarity–viscosity limit for the one-dimensional compressible Navier–Stokes–Korteweg system to the Riemann solution of the Euler system that consists of the supposition of two rarefaction waves and a contact discontinuity. It is shown that there exists a family of smooth solutions to the compressible Navier–Stokes–Korteweg system which converge to the Riemann solution away from the initial time t=0 and the contact discontinuity located at x=0, as the coefficients of capillarity, viscosity and heat conductivity tend to zero. Moreover, a uniform convergence rate in terms of the above physical parameters is also obtained. Here, the strengths of both the rarefaction waves and the contact discontinuity are not required to be small. 相似文献
258.
In this paper, we are concerned with the inverse Sturm–Liouville problem with polynomially dependent eigenparameter in discontinuity and boundary conditions. By using a self‐adjoint operator‐theoretic interpretation for this sort of problem, Ambarzumyan theorem is provided for the mentioned Sturm–Liouville operator. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
259.
Feimin Huang Jie Kuang Dehua Wang Wei Xiang 《Journal of Differential Equations》2019,266(7):4337-4376
In this paper, we study the stability of supersonic contact discontinuity for the two-dimensional steady compressible Euler flows in a finitely long nozzle of varying cross-sections. We formulate the problem as an initial–boundary value problem with the contact discontinuity as a free boundary. To deal with the free boundary value problem, we employ the Lagrangian transformation to straighten the contact discontinuity and then the free boundary value problem becomes a fixed boundary value problem. We develop an iteration scheme and establish some novel estimates of solutions for the first order of hyperbolic equations on a cornered domain. Finally, by using the inverse Lagrangian transformation and under the assumption that the incoming flows and the nozzle walls are smooth perturbations of the background state, we prove that the original free boundary problem admits a unique weak solution which is a small perturbation of the background state and the solution consists of two smooth supersonic flows separated by a smooth contact discontinuity. 相似文献
260.
黑体辐射是近代物理史上一只会下金蛋的鹅,是近代物理的摇篮。黑体辐射研究的意义还在于这是唯一一个涉及c,k,h三个普适常数的物理情景。黑体辐射谱抗测量误差的特性带来了辐射标准和绝对温度参照,谱分布公式对模型的不敏感则使得黑体辐射成为独特的物理研究母题。黑体辐射谱分布公式,普朗克多角度推导过,德拜推导过,艾伦菲斯特推导过,劳厄推导过,洛伦兹和庞加莱深入讨论过,泡利推导过,玻色推导过,爱因斯坦在20多年的时间里多角度推导过且产出最为丰硕,近代还有从相对论角度的推导,每一个角度的推导都带来了物理学的新内容,这包括量子力学、固体量子论、受激辐射、量子统计、相对论统计,等等。认真回顾黑体辐射研究的历史细节,考察其中的思想概念演化,不啻于体验一次教科书式的学(做)物理之旅,比如也可以尝试给出能量局域分立化的简单新证明。 相似文献