稳定性

PDC bit crown profile, consisting of single circular arc parabola profile or dual cone profile with deeper inner taper is introduced. Cutter arrangement for various bits is determined. The bit is improved by the application of hybrid cutting structure and detailed analysis of hydraulic structure. Simultaneously, bit stability is enhanced using multiple bit stable structure design techniques such as deep inner taper, force balance and hybrid cutter arrangement etc.

提出了以单圆弧抛物线形轮廓或双锥轮廓配以较深的内锥组成PDC钻头的冠部轮廓，确定了各种钻头切削齿的分布密度，应用了各类切削齿混合设计切削结构，对PDC钻头的水力结构做了详细分析研究；同时，结合深内锥、力平衡、混合布齿等多种钻头稳定性结构设计技术，以增加钻头稳定性。

In order to ensure system stability and reliability, use of pure software dual module hot spare mechanisms to achieve system reliability and stability, by dual module hot spare system architecture design, to implement the dual module hot spare system from the system start,"heartbeat" signal transduction, fault detection system and the main switching equipment for several major aspects.

为了保证系统的稳定性与可靠性，采用纯软件化的双机热备机制来实现系统的可靠性与稳定性，通过对双机热备系统进行总体结构设计，从系统启动，"心跳"信号传递，故障检测以及系统主备机切换等几个主要方面对双机热备系统予以实现。

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。

Firstly, we consider SIQR epidemical models with continuous and pulse vaccinations; the reproduction numbers have been obtained for those models; by using Dulac function, we prove the global stabilities of equilibrium of SIQR model with continuous vaccination. In the SIQR epidemical models with pulse vaccinations, we have also discussed the existence of the infection-free periodic solution, the global stabilities of the infection-free periodic solutions, and the effectiveness of pulse vaccination and continuous vaccination policies has been compared for the two models.

文中首先考虑具有连续免疫接种和脉冲免疫接种的SIQR传染病模型，分别获得了它们各自的基本再生数；利用Dulac函数方法证明了具有连续免疫接种的SIQR模型无病平衡点的全局渐近稳定性；在脉冲免疫接种下SIQR传染病模型里，讨论了无病周期解的存在性，证明了该周期解的全局渐近稳定性，并且对连续和脉冲接种下的SIQR传染病模型的接种效率进行了比较。

It is proved that this method can improve the system dynamic stability and the transient stability effectively.

仿真结果表明，所设计的控制方式能有效地提高系统的动态稳定性和暂态稳定性。

The stability of the n director around the grooves was studied. In one-constant model for each director, the rude condition is that the elastic constant of the n director is the maximum.

研究了双轴向列相液晶在表面沟槽上锚定的稳定性问题；稳定性条件在双轴向列相单一弹性常数近似下为n指向矢的弹性常数最大。

The carbon based materials have low electron affinity even negative electron affinity,and have the good ability of eradiating electrons in electric field.

其中非晶碳膜具有好的化学稳定性和热稳定性、高的熔点和热导率、小的介电常数、大的载流子迁移率和高的击穿电压，是一种很有前途的场发射冷阴极材料。

The general judgment of ferroelectrics perovskite stability using the tolerance factor and electronegative value of force difference,the stability of ferroelectrics perovskite can be well explained.

利用容忍因子和平均电负性力标差值作为钙钛矿稳定性的综合判据能很好说明钙钛矿稳定性。

The model in this paper takes the form as belowThe main contents and results in this paper are as follows:In section 1, we state our main analytical results on equilibria of the above system. First, several sufficient conditions for coexistence of the steady-state are given by the standard fixed-point index theory in cone. Second, the global structure of the coexistence solutions and their local stability are established by using bifurcation theory. Third, the multiplicity, uniqueness and stability of positive steady-state solutions to this system are derived by means of perturbation theory of eigenvalues, standard regularity theory, Sobolev embedding theorem and fixed-point index theory.

本文主要有两章内容：第一章研究了该模型正平衡解的性质，可分为三部分：第一部分运用极值原理、上下解方法和锥映射不动点指标理论得到正平衡解存在的充分条件；第二部分利用分歧理论给出了平衡态系统正分歧解的结构，并讨论了局部分歧解的稳定性；第三部分利用特征值扰动理论、标准椭圆正则化理论、Sobolev嵌入定理及指标理论讨论了正平衡解的多重性、唯一性及稳定性，并讨论了参数对解的影响。

Using the latest linear way and imported belts ensures stability and durability of the embroidery frame.

采用最新直线导轨设计及进口皮带，确保花架稳定性及耐用性，保持刺绣精确度。X方向采用3条皮带设计（680mm及750mm机专用），Y方向采用5条皮带设计，确保刺绣产品在花架任何位置的稳定性。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。