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1.
本文综述了关于熵数和非紧性的测量的插值性质,本文也描述了经典结果及几个非常新的结果。  相似文献   

2.
半线性热方程整体解的存在性与非存在性   总被引:10,自引:0,他引:10  
本文研究半线性热方程的初值问题ut-Δu=uγ(γ>1),u(x,0)=φ(x)的非负古典解与Lp解的整体存在性、非存在性与blow-up.首先,利用归一化的高斯函数得到了一些新的解的非整体存在的充分条件,这些条件对古典解与Lp解是普遍适用的;然后又讨论了某些非负整体解的存在性.本文不但得到了一些新的结果,而且还简化和统一了某些已知结果的证明.  相似文献   

3.
非奇异H-矩阵的实用新判定   总被引:4,自引:0,他引:4  
本文给出了几个关于非奇异H-矩阵新的实用性判定条件,改进了近期的相关结果,并用数值例子说明了文中结果判定范围的更广泛性.  相似文献   

4.
渐近非扩张的非自映象不动点的迭代逼近问题   总被引:1,自引:0,他引:1  
本文研究了渐近非扩张的非自映象不动点的迭代逼近问题,利用一致凸Banach空间中凸性模的有关不等式及新的分析方法,通过引入一新的修正的Ishikawa型迭代程序,在一致凸实Banach空间中,获得了此迭代序列强收敛于渐近非扩张的非自映象的不动点的逼近.改进和扩展了文献[2-5,9,10]的相关结果.  相似文献   

5.
庹清  陈茜 《计算数学》2019,41(2):219-224
通过构造新的正对角因子元素,本文给出了几个判定非奇异H-矩阵新的充分条件,改进和推广了"一类非奇异H-矩阵判定的新条件"一文的主要结果,并用数值例子说明了文中结果判定范围的更加广泛性.  相似文献   

6.
本文主要对三个渐近非扩张非自身映射引入了一种新的投影型Noor迭代程序,并在一致凸Banach空间中给出了该Noor迭代序列的弱与强收敛性定理.我们的主要结果推广和改进了该领域许多近期的结果.  相似文献   

7.
葛志昊  吴慧丽 《计算数学》2018,40(1):107-116
本文针对体积约束的非局部扩散问题构造了新的后验误差指示器,证明了后验误差指示器的可靠性以及有效性.数值算例验证了理论结果.  相似文献   

8.
本文针对Darcy-Stokes问题构造一个新的非协调的矩形单元,证明该单元的收敛性,并得到速度能量模的二阶收敛结果,数值算例验证了理论分析结果.  相似文献   

9.
本文给出了非负张量谱半径新的上下界, 且比参考文献[J. Inequal. Appl. 2015]中的结果更精确, 最后通过数值算例说明本文所给估计式的有效性.  相似文献   

10.
本文利用Brauer定理和Gerschgorin定理给出了非负矩阵A和B的Hadamard积的谱半径新的上界.数值算例表明新结果在一定条件下改进了现有的一些结果.  相似文献   

11.
Existence, uniqueness, and non-uniqueness results are given for a class of singular diffusion problems with variable diffusion rates. Continuity arguments are used on related initial value problems to produce the existence results. Uniqueness criteria are established for different sets of hypotheses and non-uniqueness results are discussed when these hypotheses fail.  相似文献   

12.
Properties of serial kanban systems   总被引:1,自引:0,他引:1  
In this paper we show some structural results of a kanban system by using results about the underlying GSMP. The main results from this connection are: dominance of allocations, optimal partition, upper and lower bounds on throughput, consistency of the IPA derivative, convexity of throughput as a function of service time parameters and concavity of throughput with respect to number of kanbans. Although the dominance and the partition results were obtained previously by sample path arguments, the proofs here are less cumbersome and generalize the earlier results. The second-order properties for kanban lines are new. These results form a basis for results in multi-product lines where proofs by sample paths require extensive notation.  相似文献   

13.
一类不确定时滞系统的鲁棒稳定性   总被引:2,自引:0,他引:2  
给出了不确定时滞系统鲁棒稳定的若干结果,同时讨论了这类系统的稳定度,改进了前人关于时滞系统稳定性和鲁棒稳定性的一些结论,并给出了应用的例子。  相似文献   

14.
The steady solution of a solitary wave propagating in the presence of a linear shear background current is investigated by the Green–Naghdi (GN) equations. The steady solution is obtained by use of the Newton–Raphson method. Three aspects are investigated; they are the wave speed, wave profile and velocity field. The converged GN results are compared with results from the literature. It is found that for the opposing-current case of the solitary wave with a small amplitude, the results of the GN equations match results from the literature well, while for the solitary wave with a large amplitude, results from the literature are seen to be not as accurate. In the following-current case, though the amplitude of the solitary wave is small, the GN results are shown to be accurate. The velocity along the water column at the wave crest and the velocity field for different cases are calculated by the GN equations. The results of the GN equations show obvious differences when compared with the results obtained by superposing the no-current results and linear shear current linearly. We find that for the same current strength, the vortex is stronger for the steep solitary-wave case than that for the small solitary-wave case.  相似文献   

15.
In this paper the influence of the gravity field, relaxation times and initial stress on propagation of Rayleigh waves in an orthotropic magneto-thermoelastic solid medium has been investigated. The solution of the more general equations are obtained for thermoelastic coupling by Helmoltz’s theorem. The frequency equation which determines Rayleigh wave velocity have been obtained. Many special cases are investigated from the present problem. Numerical results analyzing the frequency equation are obtained and presented graphically. Relevant results of previous investigations are deduced as special cases from these results. The results indicate that the effect of initial stress, magnetic field and gravity field are very pronounced.  相似文献   

16.
“向量极值问题的最优性条件”一文的注记   总被引:4,自引:0,他引:4  
本文给出了文[1]中的几个主要结果(即[1]中的推论2,定理4,定理6及定理7)的反例,进而更正了有关结果  相似文献   

17.
《Optimization》2012,61(3):207-214
Optimality results are derived for a general minimax programming problem under non-differentiable pseudo-convexity assumptions. A dual in terms of Dini derivatives is introduced and duality results are established. Finally, two duals again in terms of Dini derivatives are introduced for a generalized fractional minimax programming problem and corresponding results are studied.  相似文献   

18.
In this paper, we establish some su?cient conditions for the complete controllability of linear and semilinear impulsive systems. For the semilinear systems, we assume that nonlinearities are Lipschitzian type. We invoke the tools of nonlinear functional analysis and fixed point theorems to establish the results. The results are also compared with the existing results in the literature in order to show the effectiveness of the results obtained. Few illustrative examples are provided to substantiate the results.  相似文献   

19.
利用连续线性泛函满足的某些条件,给出了关于m-增生、奇算子的一些映射结果,这些结果是对已有文献中相应结果的改进.其中第二节中考虑了算子的奇性,运用Borsuk定理得出了m一增生、奇算子的映射定理;在第三节中讨论了凝聚映射的相应结果.  相似文献   

20.
General existence theorems for discrete optimal control problems are derived. It is assumed that dynamical equations of the system, as well as all control and state constraints, depend on the finite history of the system. All results are formulated in a general way in regular topological spaces. To prove such theorems, some basic concepts and results of the theory of the so-called multivalued mappings are necessary which are briefly summarized. The imposed assumptions are general enough to be of practical interest. The reported results thus include and generalize all known cases which are met in the discrete optimal control theory. Practical importance of the obtained results is illustrated on the so-called multiproduct inventory problem which is treated in the detail. Using the derived results we are able to show that under usual assumptions the inventory problem has an optimal solution.  相似文献   

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