参数

The parameters are one-to-multi corresponding relationships during the changing process of the piston stroke, which is quite different from the one-to-one mapping relationship in constant piston stroke compressors.

与定行程压缩机性能参数曲线的一一对应关系不同，各参数在变行程范围内表现为多值对应关系。

The effects of the structure constant of the refractive index fluctuations Cn2 and the inner scale of the turbulence l0 on the M2 factor have been analyzed quantitatively. Consequently, a new method for determining the characteristics parameters of the turbulence based on the measurement of the M2 factor by experiments has been proposed.

定量分析了表征大气湍流参数的折射率结构常数Cn2和涡旋内尺度l0对M2因子的影响，并由此提出了一种通过实验测量大气湍流中光束的M2因子，进而确定出大气湍流参数的新方法。

Firstly, the approach formulates a cost functional to turn the inverse problem into a constrained minimization problem according to least squares criterion, then the resulting constrained minimization problem is transformed into an unconstrained minimization problem by using a penalty function technique, and then the closed Fr chet derivatives of the Lagrange function with respect to the properties are derived based on the calculus of variations, finally, one can solve the resulting problem by using any gradient-based algorithm and the finite-difference time-domain method.

该方法首先以最小二乘准则构造目标函数，将逆问题表示为约束最小化问题；接着应用罚函数法转化为无约束最小化问题；然后基于变分计算导出闭式的拉格朗日函数关于特征参数的Fr chet导数；最后借助梯度算法和时域有限差分法迭代反演德拜模型参数。

To construct the parameterization form of reconstruction surface, a new algorithm for the planar parameterization of quadrilateral meshes is presented.

4提出了基于网格简化的四边形网格参数化算法，为构造重建网格的参数曲面提供了新方法。

For PDEs with small parameters, a scheme is AP if it possesses the discreteanalogy of the continuous asymptotic limit as the small parameter goes to zero.

对于含有小参数的偏微分方程，所谓一个算法是渐近保持的指的是，当相应的数值离散在小参数趋于零的时候，仍然是渐近极限的合理数值离散。

A second-order symmetric fabric tensor is introduced to the model, such as the stiffness of the contact planes, the hardening parameter, the dilatant/ contractant coefficient are made dependent of the orientation of the contact plane in order to capture the inherent and stress induced anisotropic behavior of clay.

在上述考虑微结构的饱和软粘土的弹塑性本构模型的基础上将考虑组构的各向异性的二阶组构张量引入接触面上的刚度、硬化参数、剪胀系数等参数中，由此反映材料引起的各向异性和应力引起的各向异性。

Compared with smooth tube,micro-fin tube has more geometrical parameters that influence heat transfer to different extent.Many scholars has done much work on it,but some research results are different or even contradictable.

相对于光管，微肋管的结构参数相对较多，这些结构参数的变化会不同程度地影响微肋管的换热能力，国内外的很多学者进行了研究，但结论相差较大，甚至完全相反。

Based on the radar dense data of convectional cloud on June 12,2004 in Yongdeng county,choosing two similar convectional clouds as seeding and non-seeding cloud,the remarkable changes of radar echo parameters of the seeding cloud compared with the non-seeding cloud were discussed in this paper,and the rain enhancement effect was evaluated primarily with ground observational rainfall data.The results show that many aspects of the seeding cloud,such as precipitation,life characteristic and vertical characteri...

利用2004年6月12日甘肃省永登县雷达观测对流云的加密资料，选取了2次相似对流云过程分别作为目标云和对比云，探讨了目标云作业前后较对比云雷达回波有关参数的显著变化，并结合地面雨量点观测资料对地面人工增雨作业效果进行了初步分析，结果表明：目标云在降水、生命期特征、回波垂直特征参数变化方面，表现出作业前后较对比云存在明显差异，目标云作业40 m in后地面产生0.6 mm降水，而对比云则从新生发展到减弱消散阶段经历较短的时间(30 m in)，地面并无降水产生，从而推断本次人工增雨达到了一定的预计效果。

Hence it is one of the important aspects for improving the effects of cumulus convective parameterization to select appropriate parameter.

因而选择合适的参数，是优化Gregory积云参数化方案的一个重要方面。

PSO is a population-based optimization algorithm, which mimics the social behavior of animals in a flock. It makes use of individual and group memory to update each particle position allowing global and local search optimization. The objective function considered was the total weight of the structure subjected to stresses, displacements and forces constraints. The effects of the parameters were investigated as well and such combination of tuning parameters promote a better global search behavior avoiding premature convergence while rapidly converging to the optimal solution. Results showed the effectiveness of the proposed method by comparing with ANSYS Design Optimization Tool (zero-order method). The PSO with the tuning parameters makes it an ideal method for offshore wind turbines foundations optimization tasks.(2) A reliability analysis method for pile foundation bearing axial loads based PSOThe performance function of pile foundation's axially bearing capacity sometimes is nonlinear and complex, on the basis of geometric meaning of structural reliability index, an optimum model with PSO for structural reliability analysis under arbitrary random variables was established, The PSO algorithm is very efficient to solve global optimization problemsIts use in structural reliability field presents not only the advantage of its facility of implementation, but also the possibility to obtain the design point and the failure probability with a good accuracy. In addition, PSO is a zero order algorithm, for no derivative is necessary for its implementation.

本文的研究针对桩式海上风机基础结构的特点，在国内外有关研究成果的基础上对海上风机基础结构优化设计理论和可靠度方法一些相关问题进行了较为深入的研究，具体做了以下几个方面的工作：(1)基于粒子群优化的桩式海上风机基础确定性优化设计方法桩式海上风机基础的优化设计是一个复杂的、非线性约束的优化问题，针对传统的基于梯度信息的优化方法在处理非线性问题中易陷入局部最优解的问题，本文将一种耦合惩罚函数的PSO算法引入到海上风机基础结构概念设计中，PSO算法是从群体动物聚集觅食这一活动中受到启发而发展的，该算法利用个体和群体的信息共享不断改进自身的位置从而进行局部和全局最优搜索，本文中以桩和三脚架连接段直径及壁厚为设计变量，以基础总重量作为优化的目标函数，在给定的约束条件下建立了三脚架基础优化数学模型，另外本文还研究了PSO参数变化对结果的影响，协调的参数组合可以避免陷入早熟收敛而能够快速的获得全局的最优解，通过与ANSYS优化模块的计算结果比较验证了该方法的有效性，本方法为海上风机基础的确定性设计提供了一条有效的途径。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。