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Now many kinds of mono-ginsenosides are obtained and used as medicines to meet clinic demands only by different predisposal process such as physiology, chemistry and zymolysis, isolation, purification after the extraction of total ginsenoside from ginseng"s radix, stem, leaf, follower and fruit because they cann"t be obtained by chemosynthesis yet.

目前，主要应用的方法有酶水解法改变人参皂苷结构。我国学者在人参皂苷结构改造工程方面取得了突破性进展，大连轻工业学院金凤燮教授发明的"酶转化法生产Rh_2等人参稀有皂苷"，在2003年度国家科学技术奖励大会上，获得国家技术发明二等奖。

With the help of bivariate entropy function, another programming is obtained and It's then proved that the solution of primal problem can be approximately obtained by solving a series of such programming.

这篇文章的求解是基于最大团问题的一个超方体约束下的二次规划模型，首先用二元熵函数作辅助项得到另外一个优化模型。

In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

First, an extended rough set model based on valued tolerance relation and prior probability obtained out of incomplete information system is founded. Then, as a part of the model, the attribute reduction of incomplete information system and the corresponding discernibility matrix are proposed, and the attribute reduction is obtained by the normal form transform.

作者首先从扩展粗集理论适应范围的角度出发，引入信息系统对象的先验概率，结合量化相容关系的思想，提出基于先验概率的相容关系模型，然后以该模型为基础研究了不完备信息系统的属性约简，通过严格的数学证明，得到基于分辨矩阵的属性约简算法。

The tolerance of seawater fish Japanese sea bass and black rockf ishto pH and alkalinity is studied through the experiment of acute toxicity. The median lethal concentration values are obtained by the method of probability unit. The safe concentrations of alkalinity, C032- and HC03- are obtained. The signification of pH and alkalinity is estimated with analysis of variance.

本文应用急性毒性试验方法研究了海水鱼类鲈鱼黑鲪对pH、碱度、二氧化碳体系各分量的耐受性，应用概率单位法求得半致死浓度，并得到了碱度、碳酸根、碳酸氢根等的安全浓度，应用方差分析评价了pH和碱度致毒作用的显著性，探讨了不同pH、碱度范围的主要致死因子。

First,making use of martingale method,pricing formula on European contingent claim,price of call and put option were obtained;Then the partial differential equation which price of European contingent claim satisfgied was deal with and hedging strategy for option was obtained.The sensitivity analysis was given.

首先利用鞅方法给出欧式未定权益一般定价公式，并得到欧式买权、卖权价格的解析表达式及平价关系，推广了一般Black-Scholes模型及Merton模型的结果；其次利用Ito公式给出欧式未定权益价格应满足的偏微分方程和套期保值策略；最后给出了欧式期权价格的灵敏度分析。

Edodes polysaccharides obtained through fermenting with L. edodes hyphae were pyran type of β-D- glucan, which had no essential difference from L. edodes polysaccharides obtained from fruit bodies after purification, but the output was not high.

红外光谱分析显示，香菇菌丝发酵获得的香菇多糖为吡喃型的β-D-葡聚糖，纯化后与由子实体获得的香菇多糖没有本质的不同，但产量不高。

Plate and λ/2 plate were placed inside the Nd∶YVO4KTP green laser cavity with angle 90°between their fast axis.The composite plate composed of HWP,QWP and KTP has the function of QWP.The composite plate with Nd∶YVO4 can effectively suppress the coupling of polarized modes,and multi-longitudinal-mode lownoise green laser was obtained.Since the composite plate counteracted the phase shift induced by temperature sensitivity of quartz plate,the green laser operated with lownoise reliability in different output power and different operation temperature.The threelongitudinalmode, the noise of less than 0.5% and output power stability of less then 1% for 12 hour are obtained in the green laser.

介绍了一种LD泵浦腔内倍频全固体Nd∶YVO4KTP多纵模、低噪音、高功率稳定绿激光器在Nd∶YVO4KTP绿激光器组成的谐振腔内放置厚度约相等的石英晶体λ2波片和λ4波片，使两波片快轴夹角互呈90°，HWP、QWP与KTP构成复合波片，其作用相当于QWP，此复合波法与各相异性Nd∶YVO4共同作用有效抑制了腔内偏振模耦合，获得多纵模低噪音绿光输出此复合波片相互作用由于抵消了石英晶体波片温度敏感引起的相位延迟量漂移，所以此激光器在不同功率、不同工作温度下，均能稳定可靠地运转于低噪音状态实验结果为，绿光输出纵模数为3个，噪音小于0.5%，12 h功率稳定性优小于1

First, a smooth curve is obtained from the data by curve fitting with the method of non-linear least squares fit. Then the tangent vector and the radius of curvature of each point on the curve can be calculated for the error evaluation. With the fitted curve, the focusing state of the aspheric lens can be obtained by the method of ray tracing.

主要过程为首先采用非线性最小二乘拟合的方法进行曲线拟合，并计算出曲线上各点的切矢量和曲率半径，分析它们的误差，最后对拟合后的曲线用光线追迹的方法得到非球面镜的聚焦情况。

Different noises are added to the ideal CITs which is obtained by using randle equivalent circuit ,and then, the de-noising criterion in practice for CITs using the empirical mode decomposition is obtained.

通过计算机仿真，在模拟等效电路生成的理想瞬态响应信号上加入不同形式的噪声，获得恒电量瞬态响应信号经验模式分解滤波的实际判据。

More direct, directer ; most direct, directest

径直的，笔直的

Do you know how to use a chain saw?

你知道如何使用链锯吗？