平衡点

All equilibrium points of the original system are stable equilibrium points in the adjoint system.

对于一个非线性自治动力系统，存在一个伴随系统，该伴随系统是一个梯度系统，原始系统的所有平衡点都是伴随系统的渐近稳定平衡点，并且每一平衡点存在解析形式的Lyapunov函数。

For a nonlinear autonomous dynamic system, there exists an adjoint system, which is a gradient system. All equilibrium points of the original system are stable equilibrium points in the adjoint system.

对于一个非线性自治动力系统，存在一个伴随系统，该伴随系统是一个梯度系统，原始系统的所有平衡点都是伴随系统的渐近稳定平衡点，并且每一平衡点存在解析形式的Lyapunov函数。

It is proved that, when the value of critical threshold less than 1, the disease free equilibrium point is globally asymptotically stable. Further more, Bursaphelenchtis Xylophilus is used to construct the Lyapunov function, and the stability theory of Lyapunov function is used to prove that the equilibrium point is Global asymptotic stable. It explains that the Bursaphelenchus Xylophilus wiil eventually disappear.

证明了当临界阈值小于1时，无病平衡点是局部渐近稳定的，进一步利用巴尔巴欣公式构造Lyapunov函数，运用Lyapunov稳定性理论证明了该平衡点的全局渐近稳定性，说明松材线虫病会最终消失；当临界阈值大于1时，病虫害平衡点是局部渐近稳定的。

While it is usually impractical for the marshallate to measure blade weight directly by weighing the sword before the basket hilt, cross, or pommel weight is attached, the linear density of the blade (its weight divided by its length) can be estimated fairly easily by weighing the finished sword, locating the point on the blade at which it balances, and measuring the distance from the point of balance to the tip, from the point of balance to the hilt, and from the point of balance to the point where the additional weight (the basket hilt, cross, or cross plus pommel weight) is attached to the blade.

而这通常是不切实际的为marshallate来衡量的刀身Weight直接由称重剑前一篮子的Hilt ，交叉，或pommel重量是重视，线性密度的刀片可估计相当容易称重成品剑，定位点的叶片在它的结余，以及测量距离平衡点，以尖端性，从平衡点到极限和从平衡点以点的额外重量（篮子的Hilt ，交叉，或跨加pommel重量）是连接到刀片。

By analysis of such models, a method, which is used to find out the region of convergence and to study the local stability for strong nonlinear system, are derived. Thus, we can consider the strong nonlinear neural networks using such method.

利用新的比较方法，考虑了具变时滞和常恢复率的同质人群HIV梯度传染病模型，得到了一个阈值，当阈值小于1时，疾病消除平衡点全局指数渐近稳定，当阈值大于1时，传染病平衡点存在唯一，同时得到该传染病平衡点局部指数渐近稳定的充分条件。

A sufficient and necessary condition for nonlinear continuous time associate memory neural networks to be locally exponentially stable is obtained, and a function is defined for characterizing the domain of attraction of equilibrium point.

讨论非线性连续联想记忆神经网络平衡点局部指数稳定的判定条件及平衡点指数吸引域的估计，得到了平衡点局部指数稳定的充要条件，并引入一个特征函数，可以判定平衡点的邻域是否为指数吸引域。

A sufficient and necessary condition for nonlinear continuous-time associate memory neural networks to be locally exponentially stable is obtained, and a unction is defined for characterizing the domain of attraction of equilibrium point.

摘要讨论非线性连续联想记忆神经网络平衡点局部指数稳定的判定条件及平衡点指数吸引域的估计，得到了平衡点局部指数稳定的充要条件，并引入一个特征函数，可以判定平衡点的邻域是否为指数吸引域。

For the infective subsystem, we obtain the existent condition of the subsystem equilibrium point and the uniqueness of the positive equilibrium point by the no infectious subsystem's conclusion and the image analysis. The partial stability of the subsystem equilibrium points is discussed by analyzing eigenvalue. The condition that the system has no limit cycle is obtained by the Dulac function.

对染病子系统，利用无病子系统所得结论及图像分析法，得到了系统平衡点的存在条件，正平衡点的存在唯一性；利用特征根方法判断了系统平衡点的局部稳定性；利用Dulac函数得到了系统不存在极限环的条件；利用极限方程理论得到了系统疾病消除平衡点和地方病平衡点的全局稳定性。

Last we obtain globally asymptotically stability of boundary equilibrium by applying locally asymptotically stability and attractiveness and persistence by using uniform repeller theorem.

在第二章中研究了一类具有时滞的捕食与被捕食系统，分析了系统的正不变集，运用了特征值理论得到了边界平衡点性质，当时滞很小时，得到了系统在正平衡点局部渐近稳定的充分条件，以及当T增加到T_0时，系统在正平衡点附近产生Hopf分支的充分条件；利用局部渐近稳定性加吸引性得到了边界平衡点全局渐近稳定性的充分条件，且应用一致排斥定理得到了种群持久生存的条件。

Secondly, method of Taylor series is used to approximate the slow manifold and the O approximation of the slow manifold is given; slow dynamics such as saddle node bifurcation which has been proven to be the same as that for the full system is analyzed; at the same time, fast dynamics including bifurcation conditions and domain of attractor of the stable equilibrium are also analyzed; the attracting region which consists of the stable manifold of the unstable equilibrium and stable equilibrium is given; we found that when the inner flux decay increases, the domain of attractor is enlarged.

首先，给出了电力系统SMIB模型的时间尺度分解，得到标准的奇异摄动模型；其次，利用幂级数方法，给出了慢流形的O近似M〓，分析了在慢流形M〓上的慢动态，得到了慢子系统的鞍结分支值，并证明此分支值与原系统的鞍结分支值相同；分析了快子系统的平衡点和全局分支的存在条件，给出由不稳定平衡点的稳定流形与稳定平衡点形成的吸引域；并研究内部电压对稳定域的影响，发现稳定域随内部电压增加而扩大；最后给出整个系统的稳定平衡点的近似吸引域。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。