查询词典 differential cross section

First of all,we have given some of the basic concepts of differential equations, described the constant coefficient linear ordinary differential equation solution, for a class of second-order variable coefficient linear ordinary differential equation initial value problem, an approximate solution, the method is first unknown function of a definition for N sub-interval, and then in between each district within a constant coefficient ordinary differential equations similar to the replacement, the solution has been the problem as similar to the original analytical solution, and then gives a detailed second-order change order coefficient of linear homogeneous ordinary differential equation solution examples, the examples of the approximate method proposed in this paper is valid.

首先给出了微分方程的一些基本概念，讲述了常系数线性常微分方程的解法，针对一类二阶变系数线性常微分方程初值问题，提出了一个近似解法，本方法是先对未知函数的一个定义区间作N等分，然后在每一个小区间内用一个常系数常微分方程近似替换，所得到的解作为原问题的近似解析解，随后详细给出了一个求二阶变系数齐次线性常微分方程的解的实例，该实例说明本文提出的近似方法是有效的。

In order to obtain more general solution of second order linear differential equation with constant coefficients, which is important in theory and practice, on the basis of knowing a special of the second order linear differential equation with constant coefficients and by using the method of variation of constant, the second order linear differential equation with constant coefficients is transferred to the reduced differential equation and a general formula of the second order linear differential equation with constant coefficients is derived.

为了更多地得到理论上和应用上占有重要地位的二阶常系数线性非齐次微分方程的通解，这里使用常数变易法，在先求得二阶常系数线性齐次微分方程一个特解的情况下，将二阶常系数线性非齐次微分方程转化为可降阶的微分方程，从而给出了一种运算量较小的二阶常系数线性非齐次微分方程通解的一般公式，并且将通解公式进行了推广，实例证明该方法是可行的。

Content: By learning this course, students should grasp the elementary solution of first order differential equation, the structure theory of linear differential equation or system of linear differential equations and the solution of constant coefficient differential equation or system of constant coefficient differential equations.

主要内容：通过对本课程学习，使学生掌握一阶微分方程的初等解法、线性微分方程的结构理论和常系数方程的解法，对微分方程初值问题的一些基础理论有一定的了解，对

Limited slip differential is improved according to common differential. Not having the common differentials disadvantage of dividing the torque into two equal parts, limited slip differential can give most torque or even all torque to another driving wheel which is not revolving in order to make use of the friction of this driving wheel to produce enough traction. This will greatly increase the dynamical capability, the passing capability, the stability and the safety of automobiles on different friction roads. So limited slip differential is substitute for common differential.

防滑差速器是对普通差速器的革新与改进，它克服了普通差速器只能平均分配扭矩的缺点，可以使大部分甚至全部扭矩传给另外一个不滑转的驱动轮，以充分利用这一驱动轮的附着力而产生足够的牵引力，大大提高了汽车在双附着系数路面上的动力性和通过性，显著改善了汽车操纵稳定性，有效地提高了汽车行驶安全性，是普通差速器的理想替代产品。

According to the plane cross section assumption, configuration of a rod is expressed as a history of the cross section with arc coordinate. A special solution which stands for equilibrium in straight line state is obtained from differential equilibrium equation. Linear perturbation equation is derived and its general solution is obtained in which the integral constants are determined by constrained conditions at two ends of the rod. The condition of existence of non zero solution of the integral constants gives to the Greenhill formula of exact elastic rod model, which shows that the boundary of stable area is a closed curve and of symmetry, and inference of shearable and extensible to stability of the rod is depend on three factors: difference between flexibility of shear and extension of a section of the rod, bending stiffness and the length of the rod.

基于平面截面假定，弹性杆的位形表达为截面的弧坐标历程，根据平衡微分方程得到了两端受力螺旋作用时的直线平衡特解，导出了线性化扰动方程及其通解，积分常数根据两端铰支时的边界条件确定，并根据其存在非零解的条件得到弹性直杆精确模型的Greenhill公式，表明稳定域为一对称的封闭区域，拉/压和剪切对稳定性的影响取决于：拉/压柔度与剪切柔度之差，抗弯刚度和杆长这三个因素

Bureau of organs inside the 18 functional departments, namely, office, party office to the Personnel Section, Finance Audit Division, law enforcement Supervision Department to monitor the room, Market Management Division, Property Management Section, Housing Management Division, Property Management Division, Demolition Management Division, Housing Reform Business Management Section, Management Section, affordable housing, and housing reform fund management division transformation of the old Management Section, the Development Enterprise Management Division, Development Project Management Division, residential property management section.

局机关内设18个职能科室，即办公室、党委办公室、组织人事科、财务审计科、执法监察科、监察室、市场管理科、产权管理科、房屋管理科、物业管理科、拆迁管理科、房改业务管理科、经济适用住房管理科、房改资金管理科、旧城改造管理科、开发企业管理科、开发项目管理科、住宅产业管理科。

Use: Disassembly carriage wheel fore-end control arm ball section and knuckle, the upper arm ball section and knuckle, undertake the pressing down on of arm ball section and knuckle, transverse direction lower arm ball section and knuckle, get lost horizontal stroke pull rod end ball section and knuckle, carriage wheel fore-end control arm ball section and knuckle come off come untied.

用途：拆卸车轮前端控制臂球节与转向节、上臂球节与转向节、承压下臂球节与转向节、横向下臂球节与转向节、转向横拉杆端球节与转向节、车轮前端控制臂球节与转向节的脱开。

It researches the regularity of A (geometrical cross section area of valve), Sc (obtained by the definition of effective cross section area of valve), Sa and Sv (obtained by sonic velocity air exhaust method) to the change of the opening of valve, x. By contrastive method this thesis discusses the reliability and correlation of all methods above for solving effective cross section area of valve.

研究了 A， Sc （根据试验由有效截面积 S 的定义算出）， Sa及 Sv随阀开度 x 变化而变的规律，通过对比探讨了求解以上各种有效截面积方法的可靠性及相互关系等。

Influencing factors of dissociative cross section, change of cross section with electron energy as well as the dependence of the cross section by vibrational level of ground state are presented in the paper.

得到了解离反应截面的影响因素、反应截面随电子能量的变化情况以及分子的振动能级对反应截面的影响。

The results show that the radiative properties of randomly distributed soot aggregates for a given fractal dimension are complex functions of the monomer diameters, the number of monomers in the aggregates,and the refractive index; For a small value of the monomer diameters, the absorption cross section of soot aggregates tends to be relatively constant when the fractal dimension is small but increases rapidly when the fractal dimension exceeds two. However, a monotonical reduction in light absorption with the increase of the fractal dimension is observed for soot aggregates with sufficiently large monomer diameters, number of monomers,and refractive index. The scattering cross section , extinction cross section and single-scattering albedo increase monotonically with the increase of the fractal dimension. Overall, the results for soot aggregates differ profoundly from those calculated for the equivalent spherical particles, and the discrepancies between them will change small with the increase of the fractal dimension.

研究表明，在给定分形维数的情况下，烟尘団簇粒子的辐射特性取决于原始微粒粒径、数量及复折射率；原始微粒较小的団簇粒子，当分形维数较小时，吸收截面变化不明显，但当分形维数大于二时，吸收截面骤然增大，然而，对于具有比较大的原始微粒粒径、数量及复折射率的烟尘団簇粒子，吸收截面随着分形维数的增大而单调递减；随着分形维数的增大，団簇粒子的散射截面、消光截面及单次散射反照率均单调递增；从整体上来讲，団簇粒子的辐射特性与等效球形粒子的辐射特性存在着比较大的差别，并且这种差别随着分形维数的增大而减小。

This paper designs the communication system of radio telescope FAST.

针对500m口径球面射电望远镜FAST分布式控制系统的特点完成了其通信系统的设计。

Political sheep's step-by-step a large number of fossils unearthed in the county soil Ma Ali after rural village in the middle of sallow pelitic siltstone.

步氏和政羊化石大量出土于广河县阿力麻土乡后山村，产于灰黄色泥质粉砂岩中。