上微分

The thesis is organized as follows:In Chapter 1,a new partial differential equation model for Spontaneous Potential log in heterogeneous formations is introduced.At the same time,the existence and uniqueness of weak solution to the problem are proved,and the problem of resistance identification in SP log is studied.Furthermore,a jump condition capturing finite difference scheme is proposed and applied to solve such elliptic interface problems.The effects of various factors on SP response,which include objective layers resistivity,bed thickness,bore-hole diameter,invasion and water-flooded zones and so on,are investigated quantitatively by the proposed method, and satisfactory results are obtained.

具体安排如下：第一章首先建立复杂地层中自然电位测井的偏微分方程数学模型，证明了该边值问题弱解的存在唯一性，在此基础上研究了自然电位测井电阻率识别问题：然后发展了用于求解椭圆交界面问题的间断捕捉有限差分方法，利用该方法定量分析了目的层电阻率、地层厚度、井径、侵入带和水淹层等因素对自然电位测井响应的影响，取得了满意的结果。

In Chapter Three, we use the method of interpolation spline of differential operater to come up with the reproducing kernel in H01 with respect to bounded linear operator in H10. Then we use the reproducing kernel to develop the expression of the best approximating of bounded linear operator in H10 and prove its convergence.

第三章中，对于H_0~1中的有界线性算子，用微分算子插值样条函数的方法给出了H_0~1空间中的再生核，利用此再生核给出了H_0~1上的有界线性算子的最佳逼近的表达形式，并证明了其收敛性。

The purpose of this paper is to prove the existence of non-oscillatory solutions to second-order neutral time-lag differential equation with positive/negative coefficient by using contraction-image principle through defining an operator from a bounded,closed,and convex subset into Banach space.

通过定义有界闭凸子集到B anach空间上的一个算子，应用压缩映像原理讨论了带有正负系数的二阶中立型时滞微分方程非振动解的存在性，得到该方程非振动解存在的一个充分条件。

Five years later, Boole published Treatise on Differential Equations, followed by Treaties on the Calculus of Finite Differences.

五年后， Boole 在微分方程上出版了论文，在限定差别的微积分方面由条约跟随

On the basis of the properties of central projection and orthographic projection, the differences of different rectification approaches based on orthographic projection are explained, and it is suggested that oblique-plane-rectified photograph can produce orthographic representation of flat terrain cover; differential rectification of RS imagery based on DEM can produce orthographic representation of waved terrain cover; and true orthographic rectification based on digital ground-object model can produce orthographic representation of single objects on ground.

根据中心投影和正射投影的特点，从理论上说明了不同正射投影纠正方法之间存在的差异，认为：基于透视变换的像片倾斜纠正可生成水平地表覆被的正射投影表达；基于DEM的正射影像微分纠正可生成起伏地表覆被的正射投影表达；基于数字地物模型的真正射纠正可生成独立地物的正射投影表达。

In the range of 200~600 nm,the absorbance at 12 wavelengths was taken as characteristic parameter of artificial neural network.

人工神经网络是在生物学中神经网络理论的基础上，简化了复杂结构的偏微分方程，构成了多个神经元互联网络的结构，研究这

In this paper, we study the differential form Wus method and put emphasis on the algorithm of differential characteristic set for differential polynomial system, and its applications.

首先，在系统总结微分情形吴方法的算法的基础上，提出了一种简化算法′算法，并给出了相应的理论证明。

Differential characteristic set method ofdifferential polynomial system is used to overcome the huge difficulties in calculation.

在本文的计算过程中，用Mathematica软件编写的求解微分特征列集的程序包克服了现有计算方法中的一些困难，在很大程度上减少了本文的计算量。

The use of charged particle in an electromagnetic field equations of motion and solve the differential equations.

把电磁作用力作用到一个粒子上得出了Lorentz力公式，利用带电粒子在电磁场中的运动方程并解这个微分方程。

Because any reports on the active control of rotating disk haven't be seen in China up to now, and this experiment research is important, so the complete set of active control system of rotating disk are built independently. The push-pull type electromagnet is applied to control the vibration of the circular disk. The power amplifier circuit that can respond to wide scope in frequency from DC to AC is designed by improving the existing circuit. The sensor signal is first low-pass filtered, then the proportional control plus the differential control circuit easy used in practice are applied to finish the more effective control. The electromagnetism shield is used as possible to decrease the signal disturbance from the electromagnet to eddy sensor.

考虑到目前国内尚未见到有关旋转圆盘振动主动控制的相关报导以及实验的重要性，自行设计制作了一整套旋转圆盘振动主动控制系统：提出并采用推拉型电磁作动器来控制圆盘的振动；在改进现有电路的基础上，自行设计了具有较理想特性的驱动电磁作动器的功率放大器；根据实际控制环境的特点，设计了先进行低通滤波，再采用比例和实用的近似微分电路构成的控制器，并采用了电磁屏蔽来减小电磁铁对传感器的干扰，以实现更有效的控制。

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。