查询词典 directional

Edge detection ; first directional derivative ; extremum ; Fourier transform

边缘检测；一阶方向导数；极值；傅里叶变换

In the new method proposed, gradient direction is not directional derivative but optimized result of chaos search in local area.

该方法先在局域内用混沌优化搜索局域最优点，再将此最优点作为梯度方向，通过改变局域范围跳出局部寻优区域。

The main results, obtained in this dissertation, may be summarized as follows:1. In chapter 2, the differential property of the optimal value function with a non-compact set is studied. The expression of its lower-Hadamard directional derivative is obtained.

第2章研究了非紧致集上最优值函数的微分性质，首先给出了最优值函数的Hadamard下方向导数的表达式，其次在最优值函数的有效域为非空凸集的情况下刻画出了次微分的表达式。

By Code extraction method is to investigate the edge of each image pixel in a neighborhood Gray-scale changes in the region, using the edge of the neighboring first-order or second-order directional derivative Changes of a few simple ways to detect the edge.

经 典的边缘提取方法是考察图像的每个像素在某个邻域内灰度的变化，利用边缘邻近一阶或二阶方向导数变化规律，用简单的方法检测边缘。

The intensity gradient of image is in the direction that the shape of surface changes most, so we use directional derivative of the reflectance map as parts of objective function.

混合反射模型比漫反射或镜面反射更加接近实际。图像的梯度方向对应物体形状变化最快的方向。因此构造了含有图像梯度信息的目标方程。

Edge lines are extracted automatically from image, by acquiring points of extremum of first directional derivative vertical with edge line with Fourier transform in frequency domain.

同时，参考一阶方向导数的数值来排除一些非边缘点（一阶方向导数的数值为常数者，零也为常数）。

On fuzzy mapping F :〓→〓, the concepts of directional derivative and integralover a line segment are defined, and the increase, convexity and continuity are investigated.

作为应用，给出了一个这类凸模糊映射在〓的某一凸子集中某一点达到最小值的等价条件，并得到了某点是一个凸模糊优化问题的最优解的一个充分条件。

However, to establish global convergence for these latter methods, one must enforce either sufficient decrease conditions (the Armijo-Goldstein-Wolfe conditions)or a fraction of Cauchy decrease condition - all of which rely on explicit numerical function values, as well as explicit approximations to the directional derivative at the current iterate.

但是，为了保证后面方法的全局收敛，必须有足够的减少条件（Armijo-Goldstein-Wolfe条件）或者部分柯西减少条件——它们全都依赖于外在的数值函数值，就和在当前迭代逼近方向导数一样。

Based on the simulated data produced by PROSAIL model and field test data, the authors respectively analyzed many kinds of factors which affect some representative inversion method s, such as VI, second derivative, model inversion and the directional second derivative.

以PROSAIL模型模拟数据和地面实测数据为基础，分别分析了土壤背景、冠层反射率非各向同性以及随机噪声等因素对几类代表性反演方法的影响(植被指数法、二阶微分法、模型反演法以及方向性二阶微分法)。

By Minimum Directional Derivative analyzing,it was also found that the FTEs were of the quasi-2D structure,the direction of the current was almost parallel to the plasma flows and the axis of the flux tubes.

应用最小方向微分法，发现这些FTE事件具有准二维结构，即为圆柱形结构，其通量管轴线方向与管内电流方向及粒子运动方向基本平行。关键词：电流密度；磁通量管；磁层顶

Liapunov—Schmidt method is one of the most important method in the bifurcation theory.

Liapunov—Schmidt方法是分叉理论的最重要方法之一。

Be courteous -- even when people are most discourteous to you .

要有礼貌──即使当別人对你最不礼貌的时候。