High - strength cylindrical handle design features easy access to standard adjustable memory stop for system balancing . the valve packing is also readily accessible for routine maintenance 高强度圆柱形手柄结构具有易于调节用于系统平衡的止动记忆装置的特点。阀门填料也易于进行日常的维护保养。
This article penetratively analyses the locally asymptotic stability of equilibrium state to the single - variable system of the tumor immunity surveillance model by aid of the ordinary differential equation stability theory 摘要用严格的常微分方程稳定性理论，对肿瘤免疲监视模型的单变量系统平衡态的局部渐进稳定性做了深入分析。
Urban green spaces to improve the ecological environment , biological diversity and the maintenance of urban - urban balance has overlooked the role of ecosystems , the city is an integral and important part of the ecosystem 城市绿地对于改善城市生态环境、维持城市生物多样性以及调节城市生态系统平衡起着不可小觑的作用,因此是城市生态系统不可分割的重要组成部分。
2 ) delay - dependent asymptotic stability of a two - neuron system with different time delays based on the construction of lyapunov functionals , we obtain sufficient criteria to ensure local and global asymptotic stability of the equilibrium of the neural network 2 )变时滞的2个神经元系统的渐近稳定性分析通过构造lyapunov泛函得到了变时滞的2个神经元系统平衡点的局部和全局渐近稳定性的一些新的充分条件。
American pharmacists have recognized cordycepss various invigorating properties since almost 30 years , after finding evidences that it helps the body resist infection because it is an " adaptogen " , which helps promote endocrine system balance homeostasis 美国药剂师认可了cordyceps的各种各样的鼓舞的物产从几乎30年,在发现证据以后,它帮助身体抵抗传染因为这是" adaptogen " ,帮助促进内分泌系统平衡homeostasis 。
Therefore , its essence is damaging creature diversity , which leads to the system loss of self - maintenance , self - accommodation ability and system balance stability , finally results in the destroying of water co - system and farther intensification of environmental issues 其本质问题是水生生物多样性的破坏，由此造成系统丧失自我维持、自我调节的能力与系统平衡的稳定性，并最终导致水生生态系统的破坏和环境问题的进一步加剧。
The first part is concerned with the stability and hopf bifurcation from an equilibrium for two classes of retarded differential difference systems , while the second part deals with the existence of positive periodic solutions of retarded functional differential equations with infinite delay 本文分两个部分，第一部分研究两类三维特殊的滞后型微分差分系统平衡点的稳定性和hopf分支，第二部分讨论无穷时滞泛函微分方程正周期解的存在性。
The result showed that the tiny difference of land use structure in past years were reported in the method of ideal - point , integrating land use with social and economic development and maintenance of eco - system balance to achieve a unified benefit of society , economy and ecology 研究结果表明： “理想点法”能反映出历年土地利用结构变化间的细微差别，为使土地利用寓于社会经济发展和维持生态系统平衡之中，最终谋求社会、经济、生态三效益的统一提供有价值的参考。
Afterwards , a duffing system with delayed displacement feedback is studied by the method of multiple scales and other numerical methods . the uniform formulas for computing the critical values of time delay are given and the global diagrams of bifurcation for the periodic solutions with respect to the time delay are obtained under different parametric combinations . it is shown that the hopf bifurcation and the saddle - node bifurcation are the only two types of bifurcation observed in such a system 接下来用多尺度法及数值方法研究了一具有时滞位移反馈的duffing系统的动力学，得到了不同参数下系统平衡点发生稳定性切换时的临界时滞计算公式及关于时滞的大范围hopf分叉图，并发现saddle - node分叉及hopf分叉是系统出现周期运动的两个主要的来源。
Through such a study , it is also shown that when the time delay is long enough such that the stability switches of the equilibrium of system halt , the bifurcation branches originated from the critical time delays cannot be surely stable or unstable in the whole solution space , that is , their stability depends on cases . this phenomenon also implies that the stability of the periodic solutions on the bifurcation diagrams indicates only the stability on the local center manifo ld . some distinguished features of delay dyn 利用打靶法的数值结果说明了当系统平衡点不再发生稳定性切换时，源自这些临界时滞处的解支的稳定性在整个解空间的稳定性具有不可判定性，这也说明由多尺度法所得高阶近似判定的解支的稳定性事实上只表示解支在局部中心流形上的稳定性，而非在整个解空间中的稳定性。
