不对称

The mechanism and dynamic model of ASVG is introduced in this article at first. Then the authors point to the problems of running and control of ASVG under asymmetric conditions of power system, and put forward the asymmetric expert PID control law. Under the experimental condition of 10%negative voltage, the simulated results are given.

论述了ASVG的工作机理和在系统电压对称时的动态数学模型，并针对系统电压不对称时ASVG的运行与控制问题，分析了系统电压不对称时的被控对象模型，提出了恒电压不对称专家PID控制方法，给出了系统有15%的负序电压时的仿真结果。

In this thesis, we developed chiral proton N-O type ligands and employed them in the enantioselective addition of diethylzinc to N-diphenylphosphinoyl imines. The relationship between the structure of the ligands and the enantioselectivity was systematically studied. Furthermore, enantioselective butylation of N-diphenylphosphinoyl imines withBu〓Zn and enantioselective diphenylzinc addition to imine were also examined.

本文致力于亚胺的不对称催化有机锌试剂加成反应的研究：以手性质子型N-O配体为促进剂，对N-二苯基次膦酰亚胺进行不对称乙基锌加成反应而展开研究工作，系统地考查了手性配体的结构对反应的影响；另外，对N-二苯基次膦酰亚胺的不对称催化丁基锌加成进行了研究，并首次对亚胺的不对称苯基锌加成反应进行了初步探索。

First, the typhoon flow field is decomposed into two parts: the maximum asymmetric vortex and irrotational environmental flow field. Then the maximum asymmetric vortex is also decomposed into two parts: the maximum symmetric vortex and β-gyres. Finally, typhoon Pearl(2006) is simulated by WRF model(weather research and forcasting model), and flow fields at various times at 500hPa...

首先，将台风的流场分解成最大的、不对称的涡旋流场和无旋流场；然后将不对称的涡旋流场分解成最大的对称涡旋和不对称的β涡旋对；最后，利用WRF(weather research and forcasting)模式(V2.1.2)模拟了200601号珍珠台风，并对各时次的500hPa风场用该方法进行分解，结果表明：该方法对台风的运动机理研究和实际的台风路径预测提供了有价值的信息。

But in our insiders control transitional economy, because the shares of the companies with higher information asymmetry are overpriced, the possibility to use long term bank debt is low while if companies of this kind import long tern bank debt, the information asymmetry can be reduced. The benefit of monitoring exceeds the cost so that the corporate governance can be improved which will bring better corporate performance; shares of companies with lower information asymmetry do not get much overprice, the possibility of using long term bank debt of this kind of companies is higher while the benefit is smaller than the cost.

但在我国的内部人控制的转型经济中，信息不对称程度高的公司由于股票在公开市场的溢价程度高，引入长期银行借款的可能性反而小，其实这种类型的公司如果引入银行债务的监督，则会减轻信息不对称程度，债务的监督收益将大于债务的成本，从而带来公司治理结构的改善，最终将带来公司绩效的提升；信息不对称程度低的公司由于其股票在公开市场的溢价程度比信息不对称程度高的公司低，反而更有可能引入长期银行借款，但这种类型的公司引入长期银行借款的成本大于收益，将会导致业绩的降低。

In the fifth chapter, the author first discusses the dissymmetrical forms of their carrying objects.

第五章：首先讨论了&来／去&带宾能力的不对称表现，认为&来／去&带宾能力的不对称主要表现在历时发展过程的不对称和共时带宾能力的不对称两个方面，然后分析了&来／去&语义泛化的过程及原因。

Background : Individuals with hemiparesis frequently shift most of their body weight to uninvolved side, showing a obviously asymmetry of standing posture and weight bearing pattern. Postural asymmetry places the individual with hemiparesis at a greater risk for falls. Asymmetry weight bearing contributes to gait abnormalities.

研究背景：半边麻痹的中风患者时常会把身体的重量放在好边的脚上，让好脚去承载身体大部分的重量，因而产生明显不对称的站立姿势和两脚不对称的重量承载比例，姿势的不对称会致使患者跌倒的危险性更大，重量承载的不对称会致使患者走路时有不正常的步态。

The results showed that the CV performance of PbO〓/PbSO〓 and PbSO〓/Pb powder microelectrode transformed from PbCO〓 under the optimize condition (the positive electrode was activated by asymmetric CV and asymmetric square wave current ways and the negative electrode using asymmetric CV) were better. Their electrode performances were as good as those made from leady oxide product by ball mill under the same conditions.

结果表明，将PbCO〓先制成粉末微电极，在30℃ 1.0mol/L H〓SO4〓溶液中经过化学转化为硫酸铅粉末微电极，以不对称信号活化(对PbO〓/PbSO〓电极，采用不对称循环伏安和不对称方波电流两种方法；对PbSO〓/Pb电极，采用不对称循环伏安法)得到电极的性能最好，正极活性物质的利用率高达89％，负极的达95％。

The proposed method can work well under asymmetry element parmeters,and it is not necessary to consider the phase shift of ideal transformer or using multi-port net theory,which make the proposed method more applicable and simplify the calculat...

相分量算法不要求电力系统元件参数对称或循环对称、不利用多端口网络理论及理想变压器的移相，拓宽了故障计算的适用范围、简化了编程难度，并可推广到处理诸如线路换位不完全的参数不对称等其他电网不对称计算。

The proposed method can work well under asymmetry element parmeters, and it is not necessary to consider the phase shift of ideal transformer or using multi-port net theory, which make the proposed method more applicable and simplify the calculation program. The method is also capable of handling various unsymmetrical calcuations, such as the fault calcuation for power system without complete transposition.

相分量算法不要求电力系统元件参数对称或循环对称、不利用多端口网络理论及理想变压器的移相，拓宽了故障计算的适用范围、简化了编程难度，并可推广到处理诸如线路换位不完全的参数不对称等其他电网不对称计算。

We also simulate the environment of photon experiment, and calculate the effect by use of fourfold symmetry torsion pendulum, we find that the double frequency effect caused by gravitational gradient is reduced a magnitude when we buildup the symmetry of measurement system.

我们还对二重对称扭秤的光子实验数据进行了分析，结果发现二倍频的效应为10~(-12)Nm 的量级，通过计算分析我们发现扭秤周围环境的不对称所引入的引力梯度效应是不容忽视的，因此针对喻家山人防山洞的具体情况，我们对光子实验的实际环境进行了模拟计算，理论分析结果表明对于二重对称的扭秤而言，环境不对称的影响引起的力矩效应为5.4940×10~(-10) Nm，对于四重对称的扭秤来说，效应为1.8668×10~(-11)Nm，可以看到随着扭秤对称性的增加，引力梯度的效应减小了一个数量级。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐