速度函数

This method not only enhances the accuracy of segmentation, but also solves the bounder gap problem well, which is quite a puzzle for single level set algorithm.

该方法不但提高了分割的精度，而且能够很好地解决单一速度函数水平集算法难以处理的边界缺口问题。

Thirdly, the problems of institution investor'optimal liquidation strategy and optimal liquidation time were investigated with the conditions that the price of risky asset followed arithmetic Brown motion and liquidation velocity was limited. The problems involved the following scenes: price impact function was linear expression of liquidation velocity which was boundary closed set with an isolated point; price impact function was stochastic; price impact function was nonlinear.

接着，当风险资产的价格服从算术布朗运动，且对投资者的变现速度做出限制时，研究机构投资者的最优变现策略和最优变现时间问题，其中包括：价格冲击函数为变现速度的线性函数，变现速度是一带有孤立点的有界闭集；价格冲击是随机形式；价格冲击是变现速度的非线性函数。

The resolution kernel and the root square deviation of the inversion solution can be obtained by analyzing the spherical harmonic coefficients.

在变换后的球面域上用球谐函数来拟合速度函数，达到降低球谐系数阶数的目的。

The nature of the acceleration unit-impulse response function of unbounded medium tending to vary linearly is proved by means of asymptotic analysis. Thus, the acceleration unit-impulse response function can be regarded as the summation of a linear function and a residual part which converges to zero. Based on this decomposition, two FE-SBFE coupling procedures are presented based on system realization and truncation integral technique respectively.

本文系统研究了相互作用力-运动关系的位移表达、速度表达和加速度表达，通过比较位移、速度和加速度单位脉冲响应函数的SBFE求解过程，确定采用相互作用力的加速度表达；通过渐近分析证明了无限地基加速度单位脉冲响应函数具有随时间延长而趋于线性变化的性质；利用这一性质将加速度单位脉冲响应函数分解为一个线性函数和一个衰减到零的残余函数的和，以此为起点发展出两种FE-SBFE时域耦合方法：基于系统实现的FE-SBFE时域耦合方法和基于截断卷积的FE-SBFE时域耦合方法。

For the first patern, elastic dynamics is adopted to study the steady state rolling contact, elastic dynamics incorporating with rigid dynamics is adopted to study the non-steady state. For the steady state, the analytical solution is obtained, and for the non-steady state, the variational formulation to solve the problem numerically is derived For the later patern, the function type friction coefficient is introduced. On the basis of the quasi-stastic theories of constant friction coefficients, both the exact theory and the simplified theory of the function type friction coefficient are established, the computer programms for both the theories are also made out. Using the function type friction coefficient, Shen-Hedrick-Elkins theory's application range is extended to large creepage .

对于速度对接触体力学特性的影响，本文采用弹性动力学方法和弹性动力学与刚体动力学相结合的方法分别对稳态和非稳态两种情况进行了研究，得到了稳态情况的解析解，给出了对非稳态情况进行数值求解的变分公式；对于速度对相关物理量的影响，本文主要讨论了速度对摩擦系数的影响，在滚动接触准静态理论的基础上引进了函数型摩擦系数，建立了函数型摩擦系数的滚动接触准静态精确理论和简化理论，并分别编制了相关的计算程序，还用函数型摩擦系数将简便的Shen-Hedrick-Elkins理论的适用范围扩展到大蠕滑区。

Along with the password attack method unceasing renewal, the computation ability unceasing enhancement as well as to the operating speed request, the tradition disperses row algorithm MD5, SHA has demonstrated their shortcoming and the insufficiency day by day, and thestructure of hash function is mostly based on block cipher algorithm DES, but the HASH function security is established above the grouping function security, because the DES operand is very big, the operating speed very slowly by and its itself some characteristics, therefore disperses a row function based on the DES algorithm to have potential unsecurity.

随着密码攻击手段的不断更新、计算能力的不断提高以及对运算速度的要求，传统的散列算法MD5，SHA已日益显示出它们的缺点和不足，并且过去hash函数的构造多是基于分组密码算法DES的，而hash函数的安全性是建立在分组函数的安全性之上的，由于DES运算量很大、运算速度很慢以及其本身的一些特性，因此基于DES算法的散列函数具有潜在的不安全性。

Along with the password attack method unceasing renewal,the computation ability unceasing enhancement as well as to theoperating speed request, the tradition disperses row algorithm MD5,SHA has demonstrated their shortcoming and the insufficiency day byday, and thestructure of hash function is mostly based on block cipheralgorithm DES, but the HASH function security is established above the grouping function security,because the DES operand is very big, the operating speed veryslowly by and its itself some characteristics, thereforedisperses a row function based on the DES algorithm to havepotential unsecurity.

摘要随着密码攻击手段的不断更新、计算能力的不断提高以及对运算速度的要求，传统的散列算法MD5，SHA已日益显示出它们的缺点和不足，并且过去hash函数的构造多是基于分组密码算法DES的，而hash函数的安全性是建立在分组函数的安全性之上的，由于DES运算量很大、运算速度很慢以及其本身的一些特性，因此基于DES算法的散列函数具有潜在的不安全性。

The relationships between welding pool width, wire extension and welding parameters including welding current duty ratio, base current, peak current, welding speed and wire-feeding speed were studied. Through large numbers of welding experiments, aluminum alloy pulsed MIG welding dynamic process were identified by the curve fitting method, and the mathematical models between welding current duty ratio, base current, welding speed, wire-feeding speed and wire extension were obtained, succeeding the model between the above parameters and weld pool width.

介绍了铝合金MIG焊焊接电流占空比、基值电流、峰值电流、焊接速度、送丝速度对熔宽的影响规律，并在其基础上，通过平板堆焊试验研究了这些参数对焊接干伸长的影响规律；在铝合金机器人脉冲MIG焊平板堆焊过程各焊接参数与正面熔宽之间的传递函数的基础上，采用铝合金平板堆焊阶跃试验，利用曲线拟合法辨识了铝合金机器人脉冲MIG焊动态过程传递函数，建立了焊接电流占空比、基值电流、焊接速度、送丝速度与焊接干伸长之间的对象数学模型。

According to experiment results, the characteristics of subsidence velocity is analyzed, and the view is presented that maxinum subsidence velocity is the function of the mining area.

根据实验结果分析了采动下沉速度变化的特点，提出了最大下沉速度值是开采面积的函数，并根据下沉速度曲线的特征，建立了在不同开采面积下某一层位的下沉速度函数形式，最后根据下沉速度与下沉值的关系推导出动态下沉值的计算公式。

When gas superficial velocity was about equal to liquid superficial velocity,the probability density function of liquid holdup had a twin-peaked,when liquid superficial velocity was constant,one of the peaks would fade out and disa...

在段塞流动中，当气相折算速度和液相折算速度相差不大时，持液率概率密度函数呈双峰分布；当液相折算速度不变时，随着气相折算速度的增大，持液率概率密度函数第2峰值逐渐减小，直至消失而变为单峰分布；利用这一特征可初步确定段塞流动中气、液相流量相对大小。

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％。