上微分

The differential eguations and boundary conditions are established, based on these hypotheses. The theoretical formulary about sample atom number with different diffusion coefficient are reasoned out; the relationship between the isotope abundance ratio and the sample wastage of melting and solid samples and the samples simultaneously at evaporation and decomposition are discussed in theory.

根据这三条假设建立了样品原子数的微分方程及边界条件，推导出了不同扩散系数的样品原子数的理论公式，从理论上讨论了熔融态、固态样品以及蒸发分解同时发生的样品同位素丰度比与样品消耗量间的关系。

If air resistance is neglected, and the speed of the object is measured over several short, consecutive intervals as it falls, the differences in the speed of the object can be used to determine the acceleration due to gravity.

如果忽略空气阻力，并在几个短暂、连续的时间间隔上测量物体的速度，就可以用物体速度的微分来计算重力加速度。

Though the Waddington and von Bertalanffy programs have not been confirmed in the typical accomplishments and representations in molecular biology in general, and molecular genetics in particular, there are interesting advances that fall between those searches for broad theories couched in mathematically precise differential equation form, and the narrow classes of mechanisms, usually described in qualitative multilevel causal language, that constitute the vast majority of current biomedical explainers.

Waddington 和 von Bertalanffy氏方法，尽管其贡献和代表性并没有在一般意义上得到分子生物学或者在特别意义上得到分子遗传学的确认，但还是在以下方面产生了有益的进展，即，它使我们的广泛的理论搜寻进步到精确的数学微分方程式的形式和通常以定性的多级因果语言来描述的机理的狭窄类别之间，由此构建了当代生物医学因果辨析的主体内容。

Even so,algebraically explicit analytical solutions covered in open literatures are very few up to now,on account of mathematical difficulties in accordance with analyzing partial differentialequations.

尽管如此，因解析求解各种偏微分方程在数学上有一定的难度，所以，国际上的公开文献中关于代数显式解析解的报道少之又少。

A time domain differential equation model is established by using the axisymmetrical form of the Maxwell's equations,and the finite element time domain method is applied to solve the model.

使用麦克斯韦方程组的轴对称形式建立时域微分方程数学模型，应用时域有限元法求解，给出了数值算例，模拟了在不同缺陷参数下涂有电介质的导体对入射脉冲太赫兹波的响应，并归纳了响应在空间上和时间上的变化规律。

It is indicated that, the bending curve is not asymmetrical and there will not have moment of flexure on the top of the bending section. Based on a slantwise constant-thick beam which foot is fixed, and took deadweight of bending section to account, a theoretical differential equation of third order for buckling equilibrium state was established.

在分析了顺层斜坡地质原型变形形态的基础上，由考虑自重的阻滑端固定的斜置等厚弹性板梁模型，提出了以地质原型变形形态抽象出相应边界条件的分析方法，及理论上求解挠曲线的适定三阶微分方程。

The thesis consists of three parts:The first part deals with optimal Sobolev inequalities on compact Riemannian manifolds;the second part is concerned with some variational models in image processing,and we propose variational models as well as experimental results for detection,denoising and mosaicking;the last part deals with inverse differential geometry in 3-D non-local image restoration.

本论文由三个部分组成。第一部分是流形上的非线性分析：第二部分是基于能量极小化方法的图像处理；第三部分是三维非局部图像重建及逆向微分几何。在第一部分中，我们研究了紧致流形上的最优Sobolev不等式，证明了某些不等式虽然就整体而言是不成立的，但总是局部成立的。

By the translational and rotational velocity information, we can get the curvatures of the curve.

然后对B-spline曲线微分得到曲线上的速度和角速度资讯，根据此速度和角速度我们便可得到曲线上的曲率时间函数。

Based on the detailed analyzing of impact system working process, the differential eguation of the system was got, and the mathematical model of the hydraulic impact system was builted, on basis of the mathematical model, By using of dynamic simulation function of Matlab ,the author has built the simulation model of the impact system based on software Simulink and run it after inputting the parameter ,the dynamic graph curve of impact velocity and presser of oil and position of knife rest were got, and the dynamic characteristic of impact system was analyzed,the simulated results are accorded with the fact,and some rational parameters can be found.

在对冲击式采煤机液压冲击系统工作过程进行详细分析的基础上，运用微分方程建模方法，建立了液压冲击系统的数学模型即系统的动态方程，并在该数学模型的基础上，采用Matlab中的Simulink动态仿真功能，建立了基于Simulink的冲击系统仿真模型，通过给定冲击式采煤机冲击系统的相关参数，对该系统进行仿真，得到了冲击式采煤机工作过程中冲击速度和油液压力以及刀架位移的变化曲线，进而对冲击系统的动态特性进行了分析，结果与实际情况较为吻合，并由此得出某些合理的参数。

But when the pressure is bigger than 30MPa, there is a contrary phenomenon. The flow rate, particle size distribution and void fraction of the extraction bed have the complicated effect. 3Based on the broken-intact cells model, a dynamic model based on differential mass balance equation is developed according to the law of conservation mass. The expression of mass transfer flux is given by the analysis the process and the necessary hypotheses. The extraction process is described, and the expression of extraction rate of diosgenin is given.

3在引入破碎—完整细胞结构理论的基础上，根据质量守恒原理建立了基于微分质量守恒方程的动力学模型，通过对萃取过程的分析和必要的简化、假设，给出了不同阶段传质通量的表达式，在此基础上描述了萃取过程，并给出了超临界流体萃取薯蓣皂甙元的萃取收率表达式。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。