极值问题

According to the analysis of reasons of transformer mal-operation in Pingdingshan Electric Power Bureac for years , and according to the present situation of transformer protection studies and applications at home and abroad. This paper points out the shortcomings of discrimination between internal faults and magnetizing inrush, the problems existing in differentiating the slight faults of turn-to-turn in transformer are also advanced. On the base of the electromagnetic characteristics of transformer, the relations between fluxional differential current and voltage of source side analyzed, all the operating states of transformer simulated by EMTP/ATP, the criterion of magnetizing inrush in transformer is got. Through the wavelet analysis of current waveform, using the intense reaction of wavelet transform to the little change of signal, the internal faults of transformer are distinguished by testing local extremum.

本文根据平顶山市电业局历年来变压器保护误动的原因分析，并根据国内外变压器保护使用和研究的现状，指出了现有变压器保护在区分变压器励磁涌流和内部故障方面以及在判断变压器匝间轻微故障方面存在的问题和不足；从变压器电磁特性出发，分析了电源侧电压和电流微分之间的关系，利用电磁暂态仿真程序对变压器各种运行状态进行了仿真，并以此建立了判断变压器是否含有励磁涌流的判据；通过对电流波形的小波分析，利用小波变换对信号微小变化极强的反映能力，通过检测电流的局部极值点来区分变压器运行状态，并作为上述判据的补充。

To cope with highly nonlinear, nondifferentiable and multi-peak objective function, evolutionary algorithms which have the advantage of global solution searching can overcome the drawbacks of conventional algorithms such as slow speed, relatively poor precision and convergence to local solutions.

针对微波领域中优化问题的目标函数的高度非线性、不可导、多极值等特点，利用演化算法的全局搜索特性，可以避免确定性优化方法收敛速度慢、精度低、易于收敛到局部极小值的缺点。

In view of this problem,a parameter extremum optimization model is developed,in which such error factors as the decaying DC components,nonsynchronous sampling and harmonics are precisely depicted.A new measuring method based on the hybrid genetic algorithmis developed to use this model for finding accurate power system parameters such as the amplitude,phase,frequency and harmonics.

针对这一问题，建立了电力参数极值优化模型，同时对衰减直流分量、非同步采样及谐波等多个误差参数加以精确表示，利用混合遗传算法对该模型进行求解，可得到准确的系统幅值、相位、频率及谐波等电力参数。

Mutual information functions are often unsmooth. There are lots of local maximums, which abversely obstruct optimization algorithms.

但是，基于互信息的目标函数经常是不光滑的，存在许多局部极值，给问题的求解带来了很大的困难。

So the accuracy of structured light methods hinges on the ability to locate the "center" of the 3D information. New method presented in this paper starts by convolving a given image with masks in a selected number of directions.

但是由于物体表面形状、反射特性比较复杂，而传统的确定结构光条纹中心位置的方法极值法、门限法、重心法、高斯拟合法等都存在不足，这就使得结构光条纹中心位置的准确检测成为影响三维信息获取精度的关键问题之一。

By this, we can obtain the space information, however, because of the body sharp and reflex characters are more complicated, and the traditional way which used for detecting the center of structured light have some weakness. So the accuracy of structured light methods hinges on the ability to locate the "center" of the 3D information. New method presented in this paper starts by convolving a given image with masks in a selected number of directions.

但是由于物体表面形状、反射特性比较复杂，而传统的确定结构光条纹中心位置的方法极值法、门限法、重心法、高斯拟合法等都存在不足，这就使得结构光条纹中心位置的准确检测成为影响三维信息获取精度的关键问题之一。

Sothe accuracy of structured light methods hinges on the ability tolocate the "center" of the 3D information. New method presented inthis paper starts by convolving a given image with masks in aselected number of directions.

但是由于物体表面形状、反射特性比较复杂，而传统的确定结构光条纹中心位置的方法极值法、门限法、重心法、高斯拟合法等都存在不足，这就使得结构光条纹中心位置的准确检测成为影响三维信息获取精度的关键问题之一。

The value of the peak factor was discussed with the crossing theory and reliability theory.

从随机极值理论和工程实际应用2个方面入手，对峰值因子的取值问题进行探讨。

Explain how to draw the experimental curves. The advantage of using figure to expression experimental data is clearly,easy to compare, and easy to see the extreme value point and turning point, periodic rate and other properties in the data.

问题补充：说明如何绘制实验曲线实验数据用图形表示的优点是直观清晰，便于比较，容易看出数据中的极值点、转折点、周期性变化率以及其它特性。

In the traditional neural networks based on gradient decline, nonlinear object functions with multiple extrema are easy to get stuck in the problem of local optimization solution. Therefore, a new method of chaos optimization neural network with weight learning is introduced in this paper.

针对传统的基于梯度下降法BP神经网络中存在非线性多极值目标函数易陷于局部最优解的问题，提出了一种权值学习混沌优化的神经网络方法。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。