查询词典 operator equation

Through creating a differential equation whose oscillation is equivalent to the impulsive equation, or considering the relation between impulsive points and delay, we get some sufficient conditions for the oscillation of the equation.

第二章讨论了二阶自共轭脉冲微分方程，通过建立与之振动性等价的微分方程，或考虑脉冲点与时滞间的关系，我们得出方程振动的一些充分条件。

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。

Therefore,it is necessary to research diffusion equation for suspended sediment because it describes the sediment move process in the water body.The equation is a various coefficients second-order linear partial differential equa-tion,such equation under complex boundary condition is very difficult to get its analytical solution,while its numerical solution relative analytical solution is more easier and has the obvious superiority:simple,the computation convenience.but to get a kind of difference format which is good accuracy and stability is not easy.

泥沙扩散方程实际上是一个变系数的二阶线性偏微分方程，这样的方程在各种复杂边界条件下求解是十分困难的，求它的解析解在数学上存在着难以克服的障碍，无法求出其精确解，因此常用数值方法求它的近似解，相比较而言，数值方法有着明显的优势：即简单灵活、计算方便快捷，但要寻找一种精度高、稳定性好、计算方便的差分格式也并非易事。

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。

When the geometric similitude ratio of the model to the prototype was determined and the loading similitude condition was satisfied by using similitude theory in structure modeling and experimental techniques, the prototype soil parameters were derived according to the model test result. The vibrating wheel compelled by harmonic exciting force was treated as a lumped mass vibrating system by equation equity method. By using this mechanical model in vibrating compaction, soil parameters were identified according to the equivalence of vibrating differential equation. The curve fitting method of amplitude versus frequency response was used for dynamic simulation based on the systematic dynamic equation of vibrating roller-soil system.

用相似理论与模型试验法在确定了模型与原型之间的几何相似比并满足载荷相似条件后，根据模型试验结果推导出了原型土体参数；用方程对等法把受简谐激振力作用的振动轮等效为集中质量振动系统，以此作为振动压实过程的力学模型，根据振动微分方程的等效条件进行识别；用幅频特性曲线拟合法以振动压路机－土壤系统动力学方程为基础，用计算机进行动态仿真。

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。

Sodium citrate; calcium carbonate; calcium hydroxide; potassium bicorbonate; magnesium carbonate; ferrous sulphate; Zinc sulphate; copper sulphate; manganese sulphate; potassium iodide; sodium selenite.

柠檬酸钠；碳酸钙；氢氧化钙；碳酸氢钾；碳酸镁；硫酸亚铁；硫酸锌；硫酸铜；硫酸锰；碘化钾；亚硒酸钠。

All this to say that I'm glad filmmaking hasn't become completely ironic. I can enjoy an ironic film as much as the next person, but they usually involve a message of some sort. One that's delivered in a smirkingly clever way that requires little in the way of talent.

所有这些都是说，我很高兴电影制作没有变成完全讽刺艺术，我可以和下一个人一样享受讽刺电影的乐趣，虽然他们经常会被划归到一定级别，技术方面不需要很高的才能。