基于逻辑选择脉冲时滞动力系统的稳定性分析

为了使动力系统在稳定性分析上更具有一般化,能更加精确实际地刻画自然现象;针对具有逻辑选择脉冲效应的时滞动力系统,提出此系统的全局指数稳定性分析问题,可在一定程度上推广一般脉冲时滞动力系统的稳定性分析;通过引入具有逻辑选择脉冲效应的时滞非线性动力系统,并利用半张量积将该动力系统中的逻辑函数转换为代数状态空间表示,再建立脉冲型 Halanay 微分不等式来估计该动力系统中线性系统部分的 Cauchy 矩阵;基于此,对向量和函数给出了4个假设条件,得到在逻辑选择脉冲控制下的非线性时滞系统的零解全局指数稳定性判定依据,且证明了此动力系统的指数收敛率为 λ-η。     

智能型电冰箱断电延迟保护器

本文介绍了一种智能型电冰箱断电保护器的电路、工作原理及其优点。     

试论散手运动中蹬腿技术的特点及其训练

散手运动中蹬腿技术有杀伤力大,有利于近距离击打,隐蔽性强,不易被对方防守等特点,其训练方法包括基本技术训练、针对性训练和实战性训练三个步骤.     

Response ofPhloeotribus scarabaeoides (Coleoptera,Scolytidae) to ethylene in an olfactometer

The role of ethylene, pure or in formulation, in the colonization behaviour of the olive bark beetle,Phloeotribus scarabaeoides (Coleoptera, Scolytidae) has been investigated in the laboratory. Ethylene has been found to be attractive in both sexes; the formulation ethrel 48 was active in an olfactometer up to several months. Ethylene, whose concentration varies with the developmental stage or the condition of the tree or its wood, may play an important role in the primary attraction of these scolytids to their host.     

Postembryonic sensory axon guidance in Drosophila

The peripheral sensory system of the Drosophila adult has been used for the genetic analysis of axon guidance because of its accessibility for experimental manipulation and mutant screens. Wing, leg, antenna, or eye sensory axons are able to pathfind normally under different perturbations, indicating that sensory axon guidance is a highly canalized process. Similarly to other model systems, sensory growth cones seem to use multiple, simultaneous cues for guidance. In addition, sensory axons from peripheral structures seem to be capable of using alternative substrates for pathfinding. Developmental regulation could account for the high stability of axon guidance under experimental and natural perturbation conditions. Despite this flexibility, functional characterization of genes involved in sensory axon guidance is being carried out in situations where there appears to be less system redundancy.     

Effect of copulation or vaginal stimulation on melanocyte-stimulating hormone content of the hypophysis

Résumé Dans le rat, 1 h après la copulation, la concentration de l'MSH de l'hypophyse présente une diminution statistiquement significative, autant chez le mâle que chez la femelle. La stimulation vaginale avec une baguette de verre provoqua 60 et 120 min plus tard une diminution de la concentration de plus de 50% de l'MSH de l'hypophyse. Au bout de 30 min, on n'a observé aucun changement. On en déduit que la copulation ou la stimulation vaginale libère l'MSH.

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This investigation was supported by grant No. NB 04732-03 from the NIH, US. Public health Service.