查询词典 directional derivative

Furthermore, the first-order optimality condition and its equivalent reformulations for generalized semi-infinite max-min programming with a non-compact set are presented using the lower-Hadamard directional derivative and subdifferential.2. Chapter 3 studies the gradient-type methods for unconstrained optimization problems. Section 1 proposes a new class of three-term memory gradient methods. The global convergence property of the method is established. Furthermore, in order to improve the convergence property of the method, a new class of memory gradient projection methods is presented with the property that the whole sequence of iterates converges to a solution to the problem under the conditions such as pseudo-convexity and continuous differentiability of objective function. In section 2, two new classes of methods, called gradient-type method with perturbations and hybrid projection method with perturbations, are proposed. In these methods, non-monotone line search technique is employed, which makes them easily executed in computer.

第3章研究了无约束优化问题的梯度型算法，第1节提出了一类新的三项记忆梯度算法，讨论了算法的全局收敛性，进一步提出了一类新的具有更好收敛性质的记忆梯度投影算法，并证明了该算法在函数伪凸的情况下具有整体收敛性，第2节在非单调步长搜索下提出了带扰动项的梯度型算法及其混合投影算法，这两类算法的一个重要特征就是步长采用线搜索确定而不象许多文献中那样要求步长趋于零，这样更容易在计算机上实现，在较弱的条件下证明了这些算法的全局收敛性，数值算例表明了算法的有效性。

The definitions of generalized directional derivative and generalized gradient of Lipschitz functions defined on Riemannian manifold are presented. Some properties of the directional derivative and gradient are proved by using tangent and cotangent mapping. The minimization necessary condition of nonsmooth Lipschitz functions is given. Moreover, Fritz John necessary optimality condition in mathematical programming is provided on Riemannian manifold.

在黎曼流形上给出了Lipschitz函数的广义方向导数和广义梯度的概念，利用黎曼流形局部上与欧氏空间开集微分同胚的性质以及切映射和余切映射导出了广义梯度的性质和运算法则，证明了定义在黎曼流形上的函数取得极小值的必要条件是广义梯度包含零元素，并利用这些性质给出了黎曼流形上数学规划问题的Fritz John型最优性条件。

The relationship between generalized directional derivative and contingent cone is presented.

给出了广义方向导数与切锥之间的关系。

The gradient of f; its dot product with is the directional derivative of f in the direction of w .

f的梯度；它与的内积为f在 w 方向上的方向导数。

Again with an algorithm that has no explicit recourse to the directional derivative and for which ranking information is sufficient.

这是又一个不需要直接导数的算法，秩信息已经足够。

Derivatives in higher dimensions, directional derivative and gradient.

在多维度中的微分、方向导数和梯度。

We get theexistence theorem of directional derivative of convex fuzzy mapping, and discuss the relationsamong directional derivative, differential, gradient and subdifferential.

得到了这类模糊映射的凸映射的方向导数的存在性定理。

In addition, the applications of the directional derivative and differential of the fuzzy mappings from 〓 to Ein convex fuzzy programming, the applications of the fixed point theorems of increasing fuzzymappings in fishery production and the applications of the integral over a directional linesegment of the fuzzy mappings are also studied.

另外，还给出了从〓到〓的模糊映射的方向可导性及可微性在凸模糊优化中的应用、增模糊映射的不动点定理在鱼业生产中的应用及模糊映射在有向线段上积分在获取统计数字方面的应用。

Since the B-spline is a locally supported function, the smoothing formula can be strictly limited in a neighborhood of each point. The smoothing surface defined by the smoothing formula has the same convexity as that of the original image. Secondly, the edge points are detected by either computing the local extremum points of the directional derivative or computing zero-crossing of the second-order directional derivative of the smoothing surface. Finally, an example of an edge detector is given.

针对反卷积视觉模型的病态性，增加了适当的约束，给出了基于低松弛迭代格式的快速自适应滤波算法，对于一个N×N输入图象，由于变换核的局部支撑性质以及低松弛迭代格式的引入，使得快速自适应滤波算法的计算复杂度降为象素个数N〓的线性量阶N〓，就最小二乘算法的复杂性而言，优于不动点迭代算法的O以及基于FFT的预处理共轭梯度算法的O。

On the fuzzy number valued mapping F:〓→〓, we put forward the definitions ofdirectional derivative, differential, gradient and subdifferential, and with the "cut method" byusing respectively the directional derivative and differential of two crisp functions that aredetermined by F, characterize the directional derivative and differential of F.

对于模糊映射F：〓→〓，提出了方向导数，微分，梯度及次微分的概念，并通过取截集，用由F所完全确定的通常函数的方向导数和微分分别刻划F的方向导数和微分。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失