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151.
In this paper,we consider nonnegative solutions to Cauchy problem for the general nonlinear filtration equations ut-Dj(aij(x,t,u)Diφ(u))+bi(t,u)Diu+C(x,t,u)=0,and obtain the existence,uniqueness and blow-up in finite time of these solutions under some structure conditions. 相似文献
152.
153.
Bin Xie 《Journal of Mathematical Analysis and Applications》2008,344(1):204-216
The pathwise uniqueness of stochastic evolution equations driven by Q-Wiener processes is mainly investigated in this article. We focus on the case that the modulus of the continuity of the coefficients is not controlled by a linear function. Additionally, we show that the corresponding diffusion process is Feller. 相似文献
154.
Project Scheduling with Multiple Modes: A Genetic Algorithm 总被引:10,自引:0,他引:10
Sönke Hartmann 《Annals of Operations Research》2001,102(1-4):111-135
In this paper we consider the resource-constrained project scheduling problem with multiple execution modes for each activity and makespan minimization as objective. We present a new genetic algorithm approach to solve this problem. The genetic encoding is based on a precedence feasible list of activities and a mode assignment. After defining the related crossover, mutation, and selection operators, we describe a local search extension which is employed to improve the schedules found by the basic genetic algorithm. Finally, we present the results of our thorough computational study. We determine the best among several different variants of our genetic algorithm and compare it to four other heuristics that have recently been proposed in the literature. The results that have been obtained using a standard set of instances show that the new genetic algorithm outperforms the other heuristic procedures with regard to a lower average deviation from the optimal makespan. 相似文献
155.
L. V. Perova 《Computational Mathematics and Mathematical Physics》2008,48(6):1001-1023
Propagation of small perturbations in a two-layer inviscid stratified fluid is studied. It is assumed that the higher density fluid occupies the lower unbounded half-space, while the lower density fluid occupies the upper unbounded half-space. The source of the excitation is a plane wave traveling along the interface of the fluids. An explicit analytical solution to the problem is constructed, and its existence and uniqueness are proved. The long-time wave pattern developing in the fluids is analyzed. 相似文献
156.
This paper is devoted to the analysis of a one-dimensional model for phase transition phenomena in thermoviscoelastic materials.
The corresponding parabolic-hyperbolic PDE system features a strongly nonlinear internal energy balance equation, governing the evolution of the absolute temperature ϑ, an evolution equation for the phase change parameter χ, including constraints on the phase variable, and a hyperbolic stress-strain relation for the displacement variable u. The main novelty of the model is that the equations for χ and u are coupled in such a way as to take into account the fact that the properties of the viscous and of the elastic parts influence
the phase transition phenomenon in different ways. However, this brings about an elliptic degeneracy in the equation for u which needs to be carefully handled.
First, we prove a global well-posedness result for the related initial-boundary value problem. Secondly, we address the long-time
behavior of the solutions in a simplified situation. We prove that the ω-limit set of the solution trajectories is nonempty, connected and compact in a suitable topology, and that its elements solve
the steady state system associated with the evolution problem.
Dedicated to Jürgen Sprekels on the occasion of his 60th birthday 相似文献
157.
贺素香 《应用数学与计算数学学报》2006,20(2):64-70
本文改进了一个求解不等式约束优化问题的对偶算法,建立了一个相应的算法,进一步证明了该算法的收敛性.最后,给出数值结果以验证该算法的有效性。 相似文献
158.
159.
In this note,we obtain some a-priori estimates for gradient of weak solutions to a class of subelliptic quasilinear equations constructed by Ho¨rmander’s vector fields,and then prove local uniqueness of weak solutions.A key ingredient is the estimated about kernel on metirc "annulus". 相似文献
160.
This paper is devoted to studying the relationship between meromorphic functions f(z) and g(z) when their differential polynomials satisfy sharing condition weaker than sharing one value IM. 相似文献