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911.
Shiow-Yu Chang 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(9):2933-2940
This paper concentrates on the problem of the existence of equilibrium points for non-cooperative generalized N-person games, N-person games of normal form and their related inequalities. We utilize the K-K-M lemma to obtain a theorem and then use it to obtain a new Fan-type inequality and minimax theorems. Various new equilibrium point theorems are derived, with the necessary and sufficient conditions and with strategy spaces with no fixed point property. Examples are given to demonstrate that these existence theorems cover areas where other existence theorems break down. 相似文献
912.
Benedetta Morini Margherita Porcelli 《Journal of Computational and Applied Mathematics》2010,233(9):2200-2212
We propose an iterative method that solves constrained linear least-squares problems by formulating them as nonlinear systems of equations and applying the Newton scheme. The method reduces the size of the linear system to be solved at each iteration by considering only a subset of the unknown variables. Hence the linear system can be solved more efficiently. We prove that the method is locally quadratic convergent. Applications to image deblurring problems show that our method gives better restored images than those obtained by projecting or scaling the solution into the dynamic range. 相似文献
913.
质子交换膜燃料电池使用寿命低是制约其商业化应用的主要瓶颈. 其中,影响质子交换膜燃料电池寿命的一个主要因素是其所广泛使用的贵金属铂基电催化剂在燃料电池苛刻的运行环境下(如可变电压、强酸性、气液两相流等)容易发生降解,导致电催化剂性能衰减,从而降低了质子交换膜燃料电池的使用寿命. 因此,如何保持铂基电催化剂的电化学稳定性已成为质子交换膜燃料电池稳定性研究中的重大科学问题. 本论文基于作者在该领域的长期研究成果,评述了应用于质子交换膜燃料电池的铂电催化剂稳定性的研究进展. 重点关注了能够大幅改善铂催化剂电化学稳定性的策略,包括聚合物稳定策略、多孔碳封装/限域稳定策略以及载体稳定策略,并对这些铂催化剂稳定策略所面临的挑战进行了展望. 相似文献
914.
A well-known deep-blue emitting iridium(Ⅲ) complex was selected for deuterium isotope effect evaluation, both on deuterated locations and numbers, through theoretical investigation. It was revealed that the containment of the d site deuteriation of ancillary ligand picolinate enabled the non-radiative deactivation process to be repessed, and thereby improving the quantum efficiency through such a simple and controllable approach. 相似文献
915.
A double perturbation strategy is presented to solve the asymptotic solutions of a Johnson-Segalman (J-S) fluid through a slowly varying pipe. First, a small parameter of the slowly varying angle is taken as the small perturbation parameter, and then the second-order asymptotic solution of the flow of a Newtonian fluid through a slowly varying pipe is obtained in the first perturbation strategy. Second, the viscoelastic parameter is selected as the small perturbation parameter in the second perturbation strategy to solve the asymptotic solution of the flow of a J-S fluid through a slowly varying pipe. Finally, the parameter effects, including the axial distance, the slowly varying angle, and the Reynolds number, on the velocity distributions are analyzed. The results show that the increases in both the axial distance and the slowly varying angle make the axial velocity slow down. However, the radial velocity increases with the slowly varying angle, and decreases with the axial distance. There are two special positions in the distribution curves of the axial velocity and the radial velocity with different Reynolds numbers, and there are different trends on both sides of the special positions. The double perturbation strategy is applicable to such problems with the flow of a non-Newtonian fluid through a slowly varying pipe. 相似文献
916.
针对物理化学相平衡章节体系多变、知识点繁多、相图抽象等问题提出了一套系统的教学策略。首先对相平衡中的基本概念和定律进行论述,并强调重、难点;随后对章节知识点进行总结归纳,通过表格系统罗列相图的体系、相律、应用和术语;最后提出相图解读通行方法,并结合具体例子讲解这些方法、相律以及杠杆规则如何使用。 相似文献
917.
Azulene, an isomer of naphthalene, has become one of hot chemical structures in the research field of functional materials, due to its anti-Kasha’s rule emissions and unusual physicochemical properties (e.g., photophysical, electrochemical, and photoelectrochemical properties). In the past, the synthesis of azulene-based compounds is relatively inconvenient. Recently, there have been more and more reports about the synthesis strategies of the azulene-based compounds for finely tuning the physicochemical properties. In this article, we introduce several synthetic methods for kinds of azulene-based compounds which has unusual physicochemical properties. With these convenient methods and unique physicochemical properties, azulene-based compounds can be applied into many fields such as specific bioimaging, advanced molecular switches, organic field-effect transistor (OFET), organic light emitting diode (OLED), solar cells, and so forth. And these properties are also summarized here. 相似文献
918.
虽然学科教学知识(PCK)在教师教育和科学教育领域已经得到世界范围内的广泛关注,但在国内,仍然有许多教师教育者和中学理科教师并不知晓学科教学知识。学科教学知识研究尚未对国内中学理科教师的职前培养与职后培训产生实质影响。依据建构的职前理科教师PCK"四要素"结构模型,并在剖析借鉴国内外教师PCK发展经验的基础上,探索提出了包含四要素独立发展、四要素分别拓展、PCK形成、PCK整体拓展4个阶段性目标的"阶段式PCK发展策略"。 相似文献
919.
920.
Pursuit-and-evasion behavior in groups of animals is a phenomenon that can be easily observed in nature. Immediate flight upon detection is a common but not exclusive response for prey with both stay-eat behavior and run-away behavior occur during the predation process. It remains unclear why these two contrasting survival tactics appear, what the triggering conditions are and what internal mechanisms are at play. Here we investigate the effect of energy level on the behavior of prey during predation. We find that (1) the optimal escape speed of prey is context-dependent rather than the fastest always producing the best chance of survival. (2) The stay-eat or run-away decision depends mainly on the maximum speed and the energy dissipation ratio of prey to predator. (3) Stay-eat behavior is more effective when the prey have a higher escape speed and a higher energy dissipation rate, where aggregation can induce this stay-eat behavior. The reported findings are not only of relevance when considering survival tactics in nature, but such an understanding is useful in the design of swarm robotic systems where energy conservation and task optimization could be incorporated into any escape and hunting strategies. 相似文献