结构方程

The stiffness equation of uniform section bending bar is the base of displacement method.

位移法是计算高次超静定结构的重要方法，等截面弯曲杆件的刚度方程是其基础。

The results of FT-IR 1H-NMR indicate the structure of polyester, and the 13C-NMR analysis of three quaternary carbon showed the existing of hyperbranched struscture, MALDI-TOF MS showed the hyperbranched polyester structure, the degree of branching of the polyesters determined by 13C-NMR being 0.408. The esterification reaction kinetics followed a second-order equation and the reaction rate was controled by the concemtration of carboxyl group and hydroxyl group,-d/dt=K.

以IR、1H-NMR证实了聚酯结构的存在，13C-NMR谱图上3种季碳的特征峰有力证实了超支化分子结构的存在，MALDI-TOF MS证明了超支化聚酯的成功合成，并计算超支化聚酯的支化度为0.408；探讨并建立了超支化聚酯的缩聚反应动力学方程－d/dt=K，该缩聚反应属于二级反应，反应速率由羟基浓度和羟基浓度共同决定。

In summary, various key experimental conditions in electron acoustic imaging of ferroelectric domains were systematically studied. The optimum experimental conditions to obtain EAI of domains with good quality and the factors important to image analysis have been presented. The piezoelectric vibrator model and calculation of motion equation are helpful for explaining the imaging mechanism and related experimental phenomena. The sample holder with variable electric field was designed. The domain movement of BaTiO〓 ceramics and crystal under lateral and longitudinal applied electric field and domain movement of PMN-PT crystal under longitudinal poling electric field were observed. The application of SEAM on revealing of ferroelastic domains, imaging of residual stress distribution in ceramics coatings and around the pores on the surface of ferroelectric ceramic composite have been reported respectively. All these works enriched the study of electron acoustic imaging and extended the application of SEAM in the characterization of materials.

综上所述，本文系统地研究了各项关键实验条件对电畴电声成像的影响，指出了获得最佳畴结构电声像的条件和成像分析中应当考虑的各种影响因素；提出了解释电畴电声成像的压电振子模型，在此基础上推导并求解了压电振子运动方程，并对一些实验现象作出了解释；成功地设计了可变电场的样品台，观察了BaTiO〓陶瓷和晶体在横向电场作用下的畴运动，PMN-PT晶体在纵向极化电场作用下的畴运动；探索了电声显微镜在铁弹畴成像，陶瓷涂层应力观察，陶瓷自然表面气孔周围应力成像的应用，这些研究，丰富了电声成像的学术内涵，拓展了电声显微镜的应用领域。

The thought of suppressing the vibration of structure with multi-part composite structure is put forward for the first time, the motion and control equation is derived, and the effect of vibration-reduction and its influential parameters are studied.

提出了利用多单体组合来抑制结构振动响应的思路，推导了其运动和控制方程，并对其减振效果和影响参数进行了研究。

But when the pressure is bigger than 30MPa, there is a contrary phenomenon. The flow rate, particle size distribution and void fraction of the extraction bed have the complicated effect. 3Based on the broken-intact cells model, a dynamic model based on differential mass balance equation is developed according to the law of conservation mass. The expression of mass transfer flux is given by the analysis the process and the necessary hypotheses. The extraction process is described, and the expression of extraction rate of diosgenin is given.

3在引入破碎—完整细胞结构理论的基础上，根据质量守恒原理建立了基于微分质量守恒方程的动力学模型，通过对萃取过程的分析和必要的简化、假设，给出了不同阶段传质通量的表达式，在此基础上描述了萃取过程，并给出了超临界流体萃取薯蓣皂甙元的萃取收率表达式。

Throughout comparing the above estimating methods, we have the following results: the estimators of the moments of the errors does not depend on the random effects, and that of the random effects does not depend on the errors, and then the corresponding asymptotic variances are very simple and optimal; when the random effects are multivariate, we can not construct different estimating equations for the random effects and errors respectively, which results that the asymptotic covariances of estimation are very complex and then the estimating efficiency is bad.

比较上述两种估计法，我们发现：当随机效应是一维的时侯，误差的各阶矩的估计不依赖不可观测的随机效应，随机效应的估计也不依赖误差，因此，估计的渐近方差结构特别简单也是最优的；而当随机效应是多维的，因为随机效应的协变量的影响，我们没有办法针对随机效应和误差的各阶矩分别建立估计方程，这导致所得的估计的渐近方差或者协方差矩阵特别复杂，从而估计的效果不是很好。

In the basis set expansionapproach, the basis function set may be chosen as the eigenstate offree-field, Volkov state and so on.

Hamilton 系统具有辛结构，Hamilton 正则方程在辛变换下形式不变，它的解由辛变换群生成。

It is based on the deep understanding of the structure properties of power flow equation.

第六章根据潮流方程的结构特征，提出了一种十分简单有效的邻近潮流解算法。

Combining with carrier rate equation,the fine structure of output spectrum and output power are numerically simulated.

结合载流子速率方程，对外腔半导体激光器的输出谱的精细结构以及P-I 特性进行了数值模拟研究。

Based on the thought of the Hyperbola Function Expansion Method, we obtained some analytical solutions of the modified Korteweg-de Vries equation by introducing new expansion functions.

基于双曲函数法的思想，通过选择新的展开函数，得到了modified Korteweg-de Vries 方程的几类精确解，其中一类为具有扭结——反扭结状结构的双扭结单孤子解。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。