查询词典 explicit differential equation

The first kind is 0-equation model. It only includes mass and momentum conservation equations. Great progresses have been made in improving this model. It has successfully been applied to many natural rivers with complicated boundary geometry. The second kind is κ-ε model. The κ equation and ε equation are needed, besides mass and momentum conservation equations. Many researchers have studied the depth-averaged mathematical models of turbulence in recent years. However, the models were used mostly in regular artificial canals or natural water areas with simple boundaries.

对于宽浅型河流，采用深度平均法进行流场计算时，用得较多的有两类模型：一类是不增加任何脉动量的偏微分方程的模型，这类模型已在适体坐标下运用得较多且较成功；另一类是κ-ε二方程模型，它是近几十年来广泛应用的一类湍流模型，并发展了许多具体的形式，但大多数只对顺直河道进行了研究，对弯曲较大的河道研究不多，本文运用适体坐标，采用正交交错网格及非正交交错网格，把此模型运用到了弯曲较大的河段及具有汇流的河段，取得了较大的成功。

McRae equation and Nicol equation describing solvent effects on absorption wavelength have been compared, and it is found that McRae equation is more suitable here.

比较了两个典型的用来描写溶剂对吸收波长影响的McRae方程和Nicol方程，发现前者在这里更为适合。

Time scale; delay dynamic equation; neutral dynamic equation; oscillation; generalized characteristic equation; Riccati transformation

基础科学，数学，数学分析时标；时滞动力方程；中立型动力方程；振动；广义特征方程； Riccati变换

Firstly, the three-dimension boundary question and its corresponding variation question concerning the point-source electrical field on a 3-D structure are presented. Secondly, the finite element method is used to solve the variational equation. The study area is divided into many tetrahedral elements. Then, we interpolate with a tri-linear function in each element. So, the variational equation is converted into a linear equation system. Finally, taking into account saving of time, we make use of symmetric successive overrelaxation preconditioned conjugate gradient algorithm to solve large linear system, and obtain the potential value of each node, resulting in the calculation of the apparent resistivity values on the ground surface.

首先给出了三维构造中点源电场的边值问题以及相应的变分问题；然后利用有限单元法求解变分问题，采用四面体单元对研究区域进行剖分，在单元中进行三线性函数插值，将变分方程化为线性代数方程组；最后，考虑到节约计算时间，利用对称超松弛预条件共轭梯度迭代算法求解大型线性方程组，得到了各节点的电位值，进而计算出地表的视电阻率。

Kinetics of methyl parathion or carbaryl adsorption could be described by First-order equation, Elovich equation and Two-constant equation.

结果表明，Langmuir方程能较好的描述甲基对硫磷和西维因在3种矿物表面的等温吸附过程，且蒙脱石对农药的最大吸附量大于高岭石和针铁矿。

In chapter 4, in the frame of partially ordered F-type topological space, we research the existence of the solution of a nonlinear operator equation Lx = Nx, and the convergence of the iterative sequence {u_n} which satisfies Lu_(n+1)= Nu_n for a solution of the equation. Then, we give the conditions for multiplicity of the solutions of this operator equation.

第四章，在半序F-型拓扑空间框架下研究一类非线性算子方程Lx=Nx解的存在性，以及满足Lu_(n+1)=Nu_n的迭代序列{u_n}对于方程解的收敛性，并给出这类算子方程具有多解性的条件。

According to the characters of iterate equation, the equation of asymmetrical three-phased state estimation can be decoupled strictly on phase coordinates, and with the rotation transformation added, the real and image part of normal equation can also be strictly decoupled.

在研究现有配电系统状态估计的基础上，根据配电系统的特点，提出了基于相坐标系的配电网三相不对称快速解耦状态估计算法。

The main contents include the ray phenomenon and its generation conditions; the deduction and physical illumination of wave action conservation equation and wave number conservation equation; ray theory for sinusoidal waves; Fermat's principle; the variation of amplitude in the case of straight and parallel depth contours and circular depth contours; the amplitude near the caustics; wave trapping; deduction of mild-slope equation and the relevant numerical solution methods.

讲授折射现象及其发生的条件；波作用守恒方程和波数守恒方程的推导及物理解释；稳恒正弦波的控制方程及射线方程；费马原理；利用射线方程研究等深线是平行直线和圆周线时波振幅的变化，特别是焦散线附近波高的变化以及由此而产生的波的俘获；缓坡方程的推导及有关的数值求解方法。

In this paper, the linear indefinite equation , quadratic indefinite equation and the several special solution of indefinite equation are studied.

本文主要研究了一次不定方程、二次不定方程和不定方程的几种特殊解法。

Through analyses, we can make the conclusion that, the relation of seed fresh weight dry weight and days after pollination, fat percent content, protein nut content, starch nut content can be expressed with Logistic equation; the change of kernel volume, moisture content of kernel and days after pollination accorded with three ascend curve equation. Kernel protein content, starch content and the changes of days after pollination tallied with reciprocal equation and they had high relation.

经过统计与分析，可以看出籽粒鲜重积累量与授粉后时间、籽粒干重与授粉后的时间、脂肪净含量、脂肪百分含量、蛋白质净含量、淀粉净含量与授粉后的时间均可以用Logistic方程描述，籽粒体积变化与授粉后的时间关系表现为三次上升型曲线方程；籽粒的水分含量与授粉后的时间关系表现为三次下降型曲线方程；籽粒中蛋白质百分含量与授粉后时间的动态变化规律、籽粒中淀粉百分含量与授粉后时间的动态变化规律符合倒数方程，均具有较高的拟合度。

As a dominant party,CPC government should play a guardian,supervisee and guarantee role to overcome all the difficulties in the development of charitable cause and bring it into full play in the establishment of harmonious society on policies and regulations basis.

在中国共产党的文献中第一次把发展慈善事业提到&最广泛最充分地调动一切积极因素，不断提高构建社会主义和谐社会的能力&的高度来认识。近年来，社会学界对慈善事业的理论专著发表较多，有鉴于此，笔者不揣浅陋，谈谈自己的认识和见解。

Flow through the land, the land of the scale of operation allows the effectiveness of the land may be raised.

通过土地的流转，土地的规模经营可以让土地的效益得到提升。