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131.
Shangjiang Guo Xianhua Tang Lihong Huang 《Nonlinear Analysis: Real World Applications》2008,9(4):1323-1335
In this paper, we consider a simple discrete two-neuron network model with three delays. The characteristic equation of the linearized system at the zero solution is a polynomial equation involving very high order terms. We derive some sufficient and necessary conditions on the asymptotic stability of the zero solution. Regarding the eigenvalues of connection matrix as the bifurcation parameters, we also consider the existence of three types of bifurcations: Fold bifurcations, Flip bifurcations, and Neimark–Sacker bifurcations. The stability and direction of these three kinds of bifurcations are studied by applying the normal form theory and the center manifold theorem. Our results are a very important generalization to the previous works in this field. 相似文献
132.
Ouyang Guangzhong 《数学年刊B辑(英文版)》1986,7(3):365-372
Let G be a locally compactb abelian group and $\[{A_p}(G)\]$ the p-Fourier algeba of Herz.
This pepar studies the space $\[{A_{1,p}}(G) = {L_1}(G) \cap {A_p}(G)\]$ with convolution product. It is
proved that $\[{A_{1,p}}(G)\]$ is a character Segal algebra. Moreover, for the multipliers of $\[{A_{1,p}}(G)\]$ the author proves that $\[M({A_{1,p}}(G),{L_1}(G)) = M(G)\]$ and $\[M({A_{1,p}}(G),{A_{1,p}}(G)) = M(G)\]$
provided G is noncompact. If G is discrete, then $\[M({A_{1,p}}(G),{L_1}(G)) = {A_{1,p}}(G)\$ and
$\[M({A_{1,p}}(G),{A_{1,p}}(G)) = {A_{1,p}}(G)\]$ 相似文献
133.
134.
合成了三种新型含噻吩环大环Schiff碱及其中一种与镧,钍的配合物。它们的结构均经IR,HNMR和元素分析表征。 相似文献
135.
136.
In this paper, we develop a deterministic inventory model for deteriorating items with two warehouses by minimizing the net present value of the total cost. Deterioration rates of items in the two warehouses may be different. In addition, we allow for shortages and complete backlogging. We then prove that the optimal replenishment policy not only exists but also is unique under some condition. Further, the result reveals that the reorder interval based on the average total cost, if it exists, must be longer than that derived using net present value. Finally, we use Yang’s [H.L. Yang, European Journal of Operational Research 157 (2004) 344–356] numerical example to illustrate the model and conclude the paper with suggestions for possible future research. 相似文献
137.
介绍了带LN2预冷的二级膨胀循环的流程计算方法,并提出了优化计算的思路和计算机程序实现的方法;最后就换热器热端温差对制冷机效率的影响进行了讨论 相似文献
138.
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140.
Living systems are open systems, where the laws of nonequilibrium thermodynamics play the important role. Therefore, studying living systems from a nonequilibrium thermodynamic aspect is interesting and useful. In this review, we briefly introduce the history and current development of nonequilibrium thermodynamics, especially that in biochemical systems. We first introduce historically how people realized the importance to study biological systems in the thermodynamic point of view. We then introduce the development of stochastic thermodynamics, especially three landmarks: Jarzynski equality, Crooks’ fluctuation theorem and thermodynamic uncertainty relation. We also summarize the current theoretical framework for stochastic thermodynamics in biochemical reaction networks, especially the thermodynamic concepts and instruments at nonequilibrium steady state. Finally, we show two applications and research paradigms for thermodynamic study in biological systems. 相似文献