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931.
A family of linear semi-infinite problems depending on a parameter is considered. For fixed , a sensitivity analysis of the problem solution is carried out and rules constructing the solutions of this family for in a right-side neighborhood of 0 are described. Results on the one-sided derivatives of the solution with respect to the parameter are presented. On the basis of the results, an active-set-strategy and a path-following algorithm are suggested.  相似文献   
932.
In many areas of nanotechnology, Germany can count on a good knowledge basis due to its diverse activities in nanosciences. This knowledge basis, when paired with the production and sales structures needed for implementation and the internationally renowned German talent for system integration, should consequently lead to success in the marketplace. And this is exactly the field of application for the innovation initiative Nanotechnologie erobert Märkte (nanotechnology conquers markets) and for the new BMBF strategy in support of nanotechnology. Until now, aspects of nanotechnology have been advanced within the confines of their respective technical subject areas. However, the primary aim of incorporating them into an overall national strategy is to build on Germanys well-developed and internationally competitive research in science and technology to tap the potential of Germanys important industrial sectors for the application of nanotechnology through joint research projects (leading-edge innovations) that strategically target the value-added chain. This development is to be supported by government education policy to remedy a threatening shortage of skilled professionals. To realize that goal, forward-looking political policymaking must become oriented to a uniform concept of innovation, one that takes into consideration all facets of new technological advances that can contribute to a new culture of innovation in Germany. And that includes education and research policy as well as a climate that encourages and supports innovation in science, business and society.  相似文献   
933.
In this paper we study bimatrix games. The payoff matrices have properties closely related to concavity of functions. For such games we find sufficient conditions for the existence of pure Nash equilibria.  相似文献   
934.
In applying the algorithm to compute the eigenvalues of a unitary Hessenberg matrix, a projected Wilkinson shift of unit modulus is proposed and proved to give global convergence with (at least) a quadratic asymptotic rate for the iteration. Experimental testing demonstrates that the unimodular shift produces more efficient numerical convergence.

  相似文献   

935.
936.
This paper proposes a co-evolutionary recurrent neural network (CERNN) for the multi-step-prediction of chaotic time series, it estimates the proper parameters of phase space reconstruction and optimizes the structure of recurrent neural networks by coevolutionary strategy. The searching space was separated into two subspaces and the individuals are trained in a parallel computational procedure. It can dynamically combine the embedding method with the capability of recurrent neural network to incorporate past experience due to internal recurrence. The effectiveness of CERNN is evaluated by using three benchmark chaotic time series data sets: the Lorenz series, Mackey-Glass series and real-world sun spot series. The simulation results show that CERNN improves the performances of multi-step-prediction of chaotic time series.  相似文献   
937.
The authors are also members of the Centre for the Study of Evolution at the University of Sussex (Email: C.J.Proctor{at}sussex.ac.uk and M.Broom{at}sussex.ac.uk) Many species of animals have to perform two contradictozy tasks:feeding, and avoiding becoming food for others. A large numberof theoretical and empirical studies have investigated the trade-offbetween feeding and antipredator vigilance, especially in birds.An important factor which has been neglected in these studiesis that of the area occupied by the flock. If individuals feedclose together, competition increases and feeding rates decrease.However, if individuals space themselves widely, then vigilanceefficiency goes down and there is an increased predation risk.We develop a vigilance model which allows birds to control thearea the flock occupies as well as their vigilance rate. Theoptimal strategy is found for the birds under a variety of environmentalconditions. In particular the effect of each environmental parameteron this optimum is considered in turn. How the model can beadapted for different bird species is also investigated.  相似文献   
938.
叶文静  刘盈莹  黄志  钟世华  杨蓉 《化学教育》2022,43(18):107-113
以提高大学生化学实验积极性和实验学习效率为目标,在“药物制剂工程实验”课程中实施能增强大学生学习自我效能感的化学实验教学策略。以“乳剂的制备”实验为研究背景,设计并实施了三阶段的实验教学流程。同时,通过构建过程性评价量化指标、开展三方评价和问卷调查等形式,对该化学实验教学策略的实施效果进行了评价。通过对比实验组和对照组学生的过程性评价成绩和问卷调查结果,发现实验组平均得分大多高于对照组,说明采用了本实验教学策略的实验组学生的自我效能感高于对照组,因此,本实验中采取的提高大学生自我效能感的化学实验教学措施确实有效且具有实际意义。  相似文献   
939.
In recent years, single-atom catalysts(SACs) have attracted increasing attention in catalysis. However, their stability is considerably challenging. As a result, fine-tuning the interaction of metal single atoms(SA) with different types of supports has emerged as an effective strategy for improving their thermal and chemical stabilities. Owing to its non-toxicity, cost-effectiveness, high abundance, and excellent stability, as well as presence of rich, tunable, and reliable anchor sites for metal SA, TiO2 has been extensively explored as a superior support for SACs. In this review, recent advances of TiO2-supported SACs(M1/TiO2) are discussed, and synthetic strategies, structure elucidation, and catalytic applications are summarized. First, the recently developed synthetic strategies for M1/TiO2arehighlighted and summarized, identifying the major challenges for the precise fabrication of M1/TiO2. Subsequently, key characterization techniques for the structure identification of M1/TiO2are discussed. Next, catalytic applications of M1/TiO2 are highlighted, viz. photocatalysis, electrocatalysis, and thermocatalysis. In addition, the mechanism via geometric structures and electronic states of metal centers facilitate catalytic reactions is outlined. Finally, opportunities and challenges of M1/TiO2 in catalysis are discussed, which may inspire the future development of M1/TiO2 for multifunctional catalytic applications.  相似文献   
940.
Protein separation can be achieved with different modes of capillary electrophoresis, such as with capillary gel electroporesis (CGE) or with capillary zone electrophoresis (CZE). CZE protein mapping of peanut extract was approached in four different ways, combining neutral-coated or multilayer-coated capillaries with pHs well over or under the isoelectric point range of the proteins of interest. At acidic pHs, the mobility ranges of the major peanut allergens Ara h1, Ara h2, Ara h3, and Ara h6 were identified. Although the pH is a major factor in CZE separation, buffers with different compositions but with the same pH and ionic strength showed significantly different resolutions. Different components of the electrolyte were studied in a multifactorial design of experiment. CE-SDS and CZE proved to be suitable for protein mapping and we were able to distinguish different batches of peanut extract and burned peanut extract.  相似文献   
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