阻尼法

The velocity of each infinitesimal element is considered as the average velocity of the above points.

表面阻尼处理的理论分析方法有复刚度法、变形能法和有限元法等。

For some shortcomings of unknown quantity numbers in finite element method, QR-method establishes a transformed relationship between a unit node displacement vector and the entire framework of spline node displacement vector,making the structure of the total stiffness matrix, damping matrix, mass matrix directly superimposed in no need of finite element method in the first expansion after the superposition process. So the method greatly simplifies the calculation process and improves computing speed.

针对有限单元法中未知量数目很多的缺点，QR法建立起单元结点位移向量与整个框架样条结点位移向量的转化关系，使得结构总刚度矩阵、阻尼矩阵、质量矩阵可以直接叠加，不需要有限单元法中先扩张后叠加的手续，大大简化了计算过程，提高计算速度。

The derivatives of the nonsmooth equations are computed to make the generalized derivative matrix nonsingular. Then the nonsmmoth damped Newton method is used to solve them.Analytic solutions of the KdV equation with variable coefficients: Shallow water wave problems belong to problems of free surface wave, and can be molded by the nonsmooth equations model given above in principle.

在前面建立的非光滑方程组数学模型和固定网格法基础上，利用广义导数的概念给出了求解渗流自由面的一种新方法-----非光滑阻尼牛顿法，该法是对非光滑方程组求导，适当的处理广义导数矩阵使其非奇异，利用非光滑牛顿法求解。

At last, the MC method,PPEM, and the frequency transfer function perturbation method have been used to analyze the effect of structural random damping onstructural displacement.

在论文的最后，利用Monte Carlo法、摄动虚拟激励法、频域传递函数摄动法研究结构随机阻尼对结构位移响应的影响。

At last, natural frequencies of practical pre-stressed composite space truss are tested with pulsatory method on construction site and its damping ratio is calculated, which gives another important data for engineering design. In addition, through the model experiment of pre-stressed rectangular square pyramid composite space truss, the correctness of characteristics of internal force and the feasibility of tension recovery method are proved.

最后，在工程施工现场用脉动法测试自振频率，并借助于振动衰减曲线和半功率点法计算出预应力组合网架——钢与混凝土的混合结构体系——的阻尼比，此又为工程设计提供了一理论依据；另外，通过正放四角锥预应力组合网架的模型试验，验证了结构内力分布特点的正确性以及张力松弛法的可行性。

The magnetic properties of carbonyl iron particle s were characterized by VSM;the apparent viscosities and the magnetic field-induced shear stresses of the magnetorheological fluids above were investigated by an advanced rheometric expansion system;the properties of MR damper were tested by an electro-hydralic servocontrol testing system.

研究了一种新型MR液和MR阻尼器；用振动样品磁强计测试了MPS-MRF-25羰基铁粉的磁性能；用磁流变仪测试了MR液的表观粘度和磁致剪切应力；用静置沉降法分析了MR液的抗沉降稳定性；用电液伺服材料性能试验机测试了MR阻尼器的性能。

Therefore, the hybrid method was adopted to determine the equivalent material properties. In this paper, the modal testing and numerical analysis were applied to obtain the Frequency Response Function and to calculate the equivalent spring constant and damping ratio of the suspension.

因此本文针对汽车悬吊部分，先以模态试验法与数值分析方法，将悬吊部分以线性弹簧及阻尼来模拟，并使用混合法，结合实验与数值之结果进行参数调整，在此是以FRF Base 来实施参数调整，确立悬吊系统的等效弹簧系数与阻尼系数。

This dissertation gives the damping iteration method and geome-tric-mean tracing method, both based on inversion of observed ground-water level data, and also gives the proportional iteration (or ortho-gonalization) method based on inversion of hydrogeologic gradient data.

本文建立了用水位观测资料进行反演的阻尼迭代法和几何均值追踪法，利用水力梯度资料进行反演的比例迭代法。

The constitutive equation is adhesion-elastic Kelvins modelconstructed by a spring and damper in parallel form.It only needs to know thestiff and damping coefficient of agricultural granule in order to realize the DEMsimulation.

以开尔文(Kelvin's Model)粘弹性模型作为仿真的本构方程，该模型是用一个弹簧和一个阻尼器并联而成的，只需知道一个刚度系数和一个阻尼系数就可以进行离散单元法仿真。

In this paper, the following progress has been discussed:(1) the improved conjugate gradient algorithm which combines the inversion equation;(2) the formulation for velvet gene at all directions and the approximation method of Jacobian matrics based on disturbance method;(3) the model is adjusted by analyzing the influence of damp coefficient and correction factor to inversion result ;(4) the influence of damp coefficient to the resolution of inversion is studied. to some degree, we improved the problem of "barycenter ascending shift" to electric anomalous body in 3-D resistivity inversion.

本文主要讨论了以下几个方面的内容：（1）结合反演方程式改进的共轭梯度算法；（2）基于扰动法的线源Jacobi矩阵的近似计算方法及光滑系数矩阵在各个方向上的光滑因子的计算公式；（3）通过分析阻尼系数与修改量校正量对反演结果的影响，提出了利用校正系数对模型修正量进行校正；（4）较为系统的讨论了阻尼系数λ对反演分辨能力的影响，较好的改善了三维电阻率反演中的电性异常体重心的&上漂&现象。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。