稳定性

According to the understanding of the flow characteristics, a mechanism of formation of vortex streets has been proposed to be the absolute instability of the wake, and several methods of flow control have been developed and shown successful.

根据表面流动及尾流特性的研究结果，从流动稳定性的角度提出了尾流中涡街产生的机理，在于尾流中存在着绝对不稳定的区域。基于对流动特性的理解，从改变流动稳定性的角度，寻求各种流动控制方法。试验结果表明这些方法是成功的。

In the research of stability for Lurie control systems, Lurie and Postnikov developed the concept of absolute stability.

从对Lurie型控制系统稳定性的研究中，Lurie和Postnikov提出了绝对稳定性的概念，绝对。。。

In the optimum cultivation, the total activity of peroxidase was about 3 times higher in absolutely replaced medium continuous culture than that partly added medium continuous culture.

在优化条件下，对培养基补充方式和菌株的遗传稳定性研究表明，彻底更换培养基较补充培养基提高3倍得率，转基因菌株遗传稳定性较高。

This was attributed to the poor solubility of Ag-TCNQ in acetonitrile.

研究贮氢材料，对其热稳定性研究是必不可少的，因此本文这部分首先对M-TCNQ材料的热稳定性进行了较系统的研究。

There are many difficulties in getting parameters when using Q system. In addition, the compound of strike, angle of gradient and discontinuities were not taken into consideration.

根据分级结果对比发现，Q系统具有分级指标获取困难的特点，且未能考虑边坡走向、坡角与结构面组合情况及坡高等因素对边坡稳定性的影响，难以适应边坡工程中稳定性评价的要求。

First,the concept of admissibility was given by introducing research background for periodically time-varying descriptor systems.

稳定性是控制系统的一个重要特征，稳定性的研究受到了许多学者的重视。

Based on varying process of generator terminal parameters after excitation fault, shortages of excitation protective principle of static stability boundary and asynchronous impedance boundary are analyzed. It proposed that excitation fault research relates to large-disturbance stability. Because dynamic power-angle character of generator after excitation fault is non-sinusoidal, there are differences between dynamic power-angle character and static state power-angle character. So it isn't ideal to protective operation result based on small-disturbance stability and static stability boundary criterion. At the same time, it proposed that asynchronous boundary impedance criterion is a constant reactive power circle moving adown j Xd′. It can ensure complete loss-of-excitation generator measuring impedance enter into the circle, but can't ensure the other condition measuring impedance including impossible losing synchronism enter. So loss-of-excitation protection would be maloperation when system voltage drops short and recovers or generator rejects load.③Based on stability principle, it puts forward setting conditions and calculation method of generator loss-of-excitation protection by direct measuring power-angle.

以励磁故障后发电机端的相关参数的变化为基础，通过对以静稳定边界和异步阻抗边界作判据的两类三种现行励磁保护在原理上存在的缺陷分析，发现：励磁故障是一个大干扰稳定性问题，励磁故障后的发电机的动态功角特性与静态功角特性有很大的差异，已远非正弦曲线，因此基于小干扰稳定性原理、以静稳定边界作判据的保护必然动作不理想；异步边界阻抗判据是一个下移j Xd′的等无功阻抗圆，它可以保证完全失磁后的发电机测量阻抗能进入该阻抗圆，但不能保证完全失磁之外的其它状态不会进入该阻抗圆，因此在系统电压短时下降或发电机突然甩负荷等情况下可能启动该保护使之误动。

The invasion of drilling fluid is the main cause to the damage of fractured formation. The composite salt free-gel drilling fluid is got after analyzing the influence of different kinds of such soluble adulterant as organic salt and non organic salt on the performance of the solid-free drilling fluid and studying the condition to develop the free gel structure and the method to improve the fluid's high temperature stability and inhibitive property. The experiment shows that the apparent viscosity of this system is as high as 27000 mPas when the share rate is 0.3 r/min and the high temperature reaches at the stable level of 150℃ and the HTHP filtrate loss decreases to 15 ml at 150℃.

钻井液侵入是裂缝性储层损害的主要因素之一，实验分析了无机盐、有机盐等不同类型水溶性加重剂对无固相钻井液性能的影响，研究了无固相钻井液快速弱凝胶特性形成条件以及高温稳定性和抑制能力的提高方法，研制出的无固相复合盐弱凝胶功能性钻井液高温稳定性达到150℃，具有独特的流变性（0.3r/min黏度达到27000 mPas）和优良的抑制能力（150℃HTHP滤失量小于15 mL），成本远低于甲酸盐钻井完井液。

The results showed:(1) Through glycosylated orthogonal test, When the substrate concentration is 1:2, glycosylated temperature is 60℃, the enzyme dosage is 0.5%and glycosylated time is 6 hours, glycosylating was at best, and the sugar concentration was 33%(2) through fermentation orthogonal test, when adding the yeast is 2.0%, proportion of Rhodiola and glutinous rice is 1:1, the temperature is 28℃, and fermentation time is seven days, alcoholicity of the wine was the highest and sensory evaluation was the best..

本文立足加工高品质的红景天糯米保健酒，主要对糖化条件，发酵工艺参数的确定，后发酵温度的确定，稳定性试验，膜过滤试验条件，营养成分分析等方面进行系统的研究，结果表明：(1)通过糖化正交试验，在底物浓度1∶2、糖化温度60℃、酶用量0.5％、糖化6h时糖化效果最好，糖液浓度33％；(2)通过发酵正交试验，在酵母添加量2.0％、红景天糯米比1∶1、发酵温度28℃、发酵时间7天生成的酒度最高，感官评价最好；(3)通过后发酵试验，选择10～15℃温度下后发酵，酒体澄清，感官评价最好；(4)从对红景天糯米酒稳定性分析中得知：酒体在低于-6℃时略有絮状物出现，酒体混浊沉淀的主要原因可能是蛋白质。

In chapter four, by the concept of negative definite of symmetry interval matrix, methods of analysis of interval matrix and the method of Lyapunov function, the robust absolute stability of Lurie control system with multiple nonlinearities was investigated, and some algebraic sufficient conditions in the form of inequalities of interval matrix were obtained.

在第四章，通过定义对称区间矩阵负定的概念，主要用区间矩阵分析技术和Lyapunov函数方法，研究了具多非线性的区间Lurie控制系统的鲁棒绝对稳定性，我们给出了此类区间Lurie系统鲁棒绝对稳定性的区间矩阵不等式形式的代数充分条件。

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。