参数积分

At last,for the double integral which the boundary curve of its domain of integration is denoted by the panameter equation, we will supply a directed method which do not eliminate the parameter.

对积分区域的边界曲线由参数方程表示的二重积分，我们也将给出两种不经消参数而直接计算的方法。

Area coordinates and general Duffycoordinates are employed to transform the singular integrals of the Time-Domain Electric Field Integral Equation into non-singular integrals, which can be accurately and efficiently evaluated by dividing the transformed domain of integration into sub-domains.

摘要该文首先利用参数坐标和广义Duffy坐标变换将时域电场积分方程的奇异性积分转换成非奇异性积分，然后根据时间基函数的特点将该积分转换成可以快速精确计算的分区域积分。

The discrete velocity ordinate method in the kinetic theory of gases is developed and applied to discretize the correspo

借助非定常时间分裂法和无波动无自由参数的NND耗散格式，建立直接求解微观分子速度分布函数的有限差分数值格式；研究并发展可用于离散速度坐标点选取和离散速度空间宏观取矩的高斯─埃尔米特无穷积分方法、等均间隔的牛顿─柯斯复合积分法、以勒让德多项式的根为积分结点的高斯─勒让德数值积分法，并应用于不同马赫数绕流模拟；通过对不同流域一维激波管问题、二维圆柱绕流问题和三维球体绕流的计算研究，并将计算结果与其他途径得到的研究结果诸如DSMC模拟值、N-S解及有关实验数据进行比较分析，创建了一套能有效模拟稀薄流到连续流不同流域气体流动问题简化的统一数值算法研究框架

In study on structure damage identification in time domain,error of numerical integral will affect directly accuracy of parameters resulted from reversion.

在结构损伤识别的时域法研究中，数值积分的误差将直接影响反演参数结果的精度。积分初值的未知、消除数值积分引入的误差是结构损伤反演计算中信号处理的难题。

And the further relation of these parameters is obtained by the transient response. Results show that the parameters of the PID control method for the system satisfy the following rules: the proportional parameter is larger than the derivative parameter, and the derivative parameter is larger than the integral parameter.

结果表明：为了满足数字电子气动式座舱压力变化速率和稳定性的要求，PID参数需满足一定的关系：在一定范围内，控制器的比例参数应大于微分参数，而微分参数应大于积分参数。

A program based on four kinds of methods in thermal analysis is designed for finding out the mechanism of decomposition reaction of explosives and calculating their kinetic parameters. Compared with the Kissinger's method, the program here adopted has the advantage of exploring the reaction mechanism besieds a calculation of the kinetic parameters. Mechanism of decomposition of the explosive PYX was determined applying this program. The kinetic parameters of PYX calculated by non-isothermal integral meth...

以热分析理论为依据，摒弃了以往仅用一种热分析法进行反应动力学研究和近似假设─—炸药的热分解反应机理f＝（1—α）n所带来的弊病，采取4种热分析方法（等温积分法、等温微分法、非等温微分法、非等温积分法）相结合的方法，编制了计算程序，首先判断反应机理，然后求取动力学参数，用所编程序对PYX炸药的反应动力学进行了研究，用非等温法判断了PYX炸药的反应机理，并求得动力学参数，所求参数与Kissinger法求得的结果十分接近。

In study of the truss structural dynamic characteristics analysis, randomness of the structural physical parameters and geomtric ones are all considered. The finite element model of the stochastic truss is built and the random functions of its natural frequencies are obtained by use of the Rayleigh quotient. Employing probabilistic distribution function expression for the random functions, through a series of mathematical processing including determination of limits of integrals, variable substitution etc., the probaabilistic density function for the truss natural frequencies are gained to realige accurate calculation for the reliability of the truss natural frequencies.

考虑结构物理参数和几何参数的随机性，通过构建随机参数桁架结构的有限元模型，利用瑞利商公式获得了结构固有频率随机函数的计算表达式，应用随机函数的概率分布函数表达式，通过确定积分区间、变量替换、积分顺序变换等一系列数学上的处理，获得结构固有频率的概率密度函数，进而实现对结构固有频率可靠度的精确计算。

The beam quality of a LD pumped Nd∶YAG laser is measured with CCD camera system. The background characteristics of the CCD system and the influence of the size of integral box upon measurement results are investigated. The following conclusions can be derived form experimental results:(1) Background is strongly depend upon exposure time and pixel binning,while temperature has an ignorable effect upon it,whether with or without ambient light.(2) A 5%-cut is the minimum value in order to get a reasonable result.

采用CCD系统实验测量了LD泵浦Nd∶YAG激光器的光束质量参数，研究了CCD系统的背景噪声特性和积分区域选取对光束质量参数测量的影响，从实验数据中得到以下结论：（1）在有、无背景光两种条件下，背景记数强烈地依赖于曝光时间和像素的合并，温度影响可以忽略不计，（2）为获得M2合理的测量结果，至少要选择5%积分区域。

A detailed model of non-linear parametric excitation vibration coupling the stay cable and the girder, in which the static sag as well as the geometric non-linearity are considered, is proposed in this paper. Based on several numeric examples investigated by the Galerkin method composed with the integration strategy, several kinds of factors effecting stay cable parameter vibration are studied. Another parameter vibration model by the axial excitation is presented and the corresponding nonlinear equations are derived. The smallest excitation amplitude,the transient state and steady state resonance amplitudes, and the changing characteristics of the axial force are obtained by using harmonic balance method. According to numerical examples calculated by numerical integration method, the effects of the inner damping of the stay cables are investigated.

本文创新地提出了斜拉桥拉索-桥面耦合参数振动模型，推导了索-桥耦合非线性参数振动方程组，联合Galerkin法及数值积分方法，对各种特性的拉索进行了数值求解，得出了影响拉索参数振动的各种因素；提出了斜拉索受轴向端激励参数振动模型，导出了模型的非线性振动方程，使用谐波平衡法得出了产生参数振动需要的最小激励幅值、共振时瞬态及稳态的振动幅值及索拉力的变化特性，并用数值积分方法对实际斜拉桥拉索进行了计算，分析了拉索阻尼对参数振动的影响。

In software,I used location PID control algorithm to achieve the right systemPID tuning parameters, PID controller is the ratio of integrals,integral saturation correction factor, the parameters such asintegration time, Due to reasons of space calculation unmanifestedas if this thesis, it is in the final process directly give thevalue.

在软件实现中，本人采用位置式PID控制算法来实现对系统PID参数的整定，得到PID调节器的比例、积分、饱和积分修正系数、积分时间等参数，由于篇幅原因计算过程未列如本论文内容中，只是在最后程序中直接赋予各值。

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。