查询词典 stability conditions

Lightened on the turbine valve controller designed with feedback linearization theory and introduced nonlinear tracking-differentiator, a novel nonlinear PID valve controller was proposed. This controller can fit not only to plant with some model error and random disturbance in variable, but also to the variety of the structure and operating conditions of power system. The transient and dynamic characters of the controller are both satisfactory when big and small disturbances added. The good performance, wide stable margin and heavy robustness of the valve controller proved that it is a great practical application to enhance the stability of power system.

结合反馈线性化法汽轮发电机组的汽门控制研究成果，引入非线性跟踪微分器和非线性度变换控制，进行了发电机组的非线性PID汽门控制器设计，该控制器不仅能适应一定的系统模型误差与变量的不确定性干扰，而且对于电网结构和运行工况的变化有着较强的适应能力，在受大、小扰动的情况下，呈现了较好的暂态特性和动态品质，具有较好的控制品质、较高的稳定裕度和较强的鲁棒性能，有利于进一步改善电力系统的稳定性，显示了其较强的实用性。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory. The key techniques used in numerical simulation of the three-dimensional extrusion from dies such as decision of boundary conditions, creation of initial velocity field, selection of penalty factor, high Weissenberg number problem , regeneration of the free surface were studied in detail.

中文题名聚合物异型材口模挤出三维流动研究副题名外文题名 Study on three-dimensional flow of polymer melts during the process of profile extrusion from dies 论文作者涂志刚导师柳和生包忠诩教授学科专业材料加工工程研究领域\研究方向学位级别博士学位授予单位南昌大学学位授予日期2001 论文页码总数148页关键词挤出成型聚合物材料挤出口模聚合物异型材馆藏号BSLW /2003 /TQ320 /9 本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

In view of the stability of these two formates under catalytic conditions, it is very likely that they are not within the major catalytic cycle of the reaction.

该甲酸根配合物随即转化为另一个甲酸根配合物TpRu(PPh3)(CH3OH)(η1-OCHO)并与之达成平衡，后者由于存在分子内氢键而稳定。

Based on Darcy's law, the depth distribution of the stability zone and the deposits zone of gas hydrate is quantified, and the effective factors of their boundary conditions are identified carefully with the theoretical model.

本文以达西定律为基础，通过理论模型对水合物稳定区、沉积区的深度分布进行了量化并对各自的边界条件的影响因素做了详细的分析。

The EBD adapts to individual wheel grip conditions, which helps to improve both control and stability.

在EBD适应个别车轮抓地力条件，这有助于改善两国的控制和稳定。

The interfacial polarization resistances were unvaried during this period,suggested that the SDC modified anode was stable for the direct utilization of octane,and slight degeneration in the performance was associated mainly with the loss of OCV,which was possibly derived from a little carbon deposition within the SDC-coated anode where the level is so low that it almost has no effect to cause severe damage to the anode. The fuel composition and operation conditions had remarkably influence on the cell durability,implied that the stability of the fuel cells could be further improved by varying the iso-octane/O2 ratio and conducting a continuous operation.

燃料组分和测试条件对电池稳定性有着较大影响，说明通过改善O2/iso-octane比例以及维持电池在更长时间内放电能够获得更好的长期输出性能。

Enacted law helps to maintain the universal applicability and relative stability of law, the respect of which is the general conditions of the whole society, while judge-made law takes more advantages in particular and flexible applicability of law, focusing on specific situations of individual cases.

法官造法属于个人造法，它比较容易受到法官的成见、好恶、情感、能力等个人因素的影响；而对于制定法，由于立法机关一般都是由民选代表组成的，在社会中具有广泛的代表性，而且立法者要按照民主的方式和程序集体造法，所以能更好地反映人民的意志。

In the second section, the sufficient conditions of the global asymptotic stability and uniqueness of periodic solutions are obtained for n-dimensional model.

第二节讨论了均有HolingⅡ型功能反应且具有周期系数的顺环模型，得到了该系统存在唯一全局渐近稳定周期解的充分条件。

Anionic additives were more favorable than non-ionic additives for improving the stability of CWS under same conditions of irradiation.

使用阴离子添加剂比非离子添加剂更有利于辐照对煤浆的稳定化作用。

The optimal experimental conditions for the stability of immobilized xanthan gum were produced at the pH value of 2.0 and temperature 60℃.

在本实验条件下，固定化三仙胶之结构稳定性以凝胶溶液pH为2及凝胶温度60℃为最佳操作条件。

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。