查询词典 projection gradient method

The status of gradient projection method of redundant manipulator is analysed, the effect and selection methods of the scale factor of the homogeneous solution is expatiated.

分析了冗余度机器人梯度投影法的研究现状，阐述了齐次解的比例因子的作用及其选择方法，提出了一种实时连续变化的比例因子计算方法。

In Chapter 5, the authors study the convergence properties of the gradient projection method for the constrained optimization problem. In this chapter, a new step-size rule, which avoids fulfiling the classical line search and includes choosing a constant as the step size as a special case, is presented and analyzed.

第五章研究了求解约束最优化问题的梯度投影方法，在步长的选取时采用了一种新的策略，这种策略不需要进行传统的线搜索且包含步长取常数这种特例，在较弱的条件下，证明了梯度投影方法的全局收敛性。

In order to efficiently handle multi-constraints, a vector function inner product is defined in the zero level set and a gradient projection method is constructed, and the necessary condition satisfied by the optimal solution is proved.

在这些研究的基础上，提出了适用于一般目标函数、多材料、多约束和多载荷工况的结构拓扑优化的水平集算法4.1，并给出了刚性结构、柔性机构和复合材料微结构设计算法5.1、6.1和7.1，以及大量的数值算例。

Since the gradient projection method was proposed, it has been paid much attention to because it has the following three advantages: 1 its structure is very simple, 2 it is easily operated, 3 its each computional step is iterated explictly and doesn't need to solve complex linear programming or quadratic programming problems.

梯度投影方法自提出以来，由于它简单易行，计算的每一步都是显式迭代，而不必去解复杂的线性规划或二次规划问题，因此颇为人们注意。

Considering the fact that the self constraints of the design variables can be formulated as the linear functions in the present process optimization, the nonlinear part of the constraints is dealt by introducing the concept of active constraint set. The linear part is dealt by the gradient projection method specially.

同时考虑到现在的优化求解问题中，设计变量自身的约束可以合理地表示成线性函数的形式，因此对于优化问题的非线性约束部分，通过引入活动约束集的概念进行处理；而对于线性边界约束，则采用梯度投影法作专门处理。

A problem of cable force optimization of cable-stayed bridge is equated as a nonlinear implicit optimization model. In the mathematical model, the object function is minimizing summation of bending strain energy and axial strain energy, and the constrain conditions are nonlinear and related to reasonable finished dead state. The optimization model is solved by projection gradient method, fully considering all kinds geometric nonlinearity.

把超千米级斜拉桥的索力优化问题归结为非线性隐式优化的数学模型，以系统最小弯压应变能为目标，根据合理成桥状态指定各种非线性约束条件，利用投影梯度法进行优化问题的求解，求解过程中充分考虑了各种几何非线性的影响。

Furthermore, we solve the user equilibrium problem by gradient projection method to obtain some additional path-based information. Since true OD trip demands are unknown, we conduct OD demand estimation and OD demand covering rate verification by the least square estimator.

在求解使用者均衡之交通量指派问题上，透过梯度投影法(Gradient projection， GP)求解，并获得以路径为基础的相关资讯；在流量倒推旅次起迄量的课题上，由於真实OD量未知，故使用基本的最小平方估计量，进行旅次起迄需求涵盖量的推估与检验。

In this dissertation, incorporating the level set algorithm, the gradient projection method, the nonlinear mapping technique, the return mapping algorithm and the mean curvature flow technique into topological optimization theory, a level set algorithm for topology optimization with multi-material structures is put forward, which can optimize a problem with general objective functions, multi-constraints, multi-materials and multi-load cases.

同时，又将拓扑导数理论和水平集算法结合起来，提出了结构拓扑优化的拓扑导数与水平集算法，进一步提高了计算效率。

The system parameters are determined by optimizing an output-error cost function. To deal with the non-uniqueness of the fully parameterized state-space system, a projected gradient search algorithm is presented by restricting the update of the parameters to the tangent space to the manifold of observationally equivalent state-space systems. The sufficient condition to employ L-M algorithm for optimizing parameters is also introduced. The proposed hierarchical optimization identificationmethod includes two steps: First, the parameter search direction is determined by the proposed adaptive L-M projected gradient approach; Second, the optimum step size is computed according to a line search method.

通过极小化输出误差目标函数获得了系统参数估计；提出了正交梯度搜索方法用于解决系统参数的非唯一性问题，正交梯度搜索的本质是在输入-输出等价类相切平面的正交垂空间更新系统参数；给出了用 L-M 算法进行参数优化的充分条件；提出的系统参数递阶优化辨识方法包括两步：首先用给出的自适应 L-M 算子正交梯度方法确定参数优化方向；其次由一维搜索方法计算最佳步长。

Firstly,effectively edge information was picked-up by comparing and choosing maxima from colour weight gradient images.Then,a method based on multi-threshold segmentation was proposed,which can eliminate inefficacious gradient information.Finally,procedures and results of the algorithm were introduced.

首先比较并选取彩色分量图像梯度信息的最大值，达到提取图像有效边缘信息的目的；然后提出基于多阈值分割的方法消除无效梯度信息；最后介绍了算法的步骤及结果。

When this condition occurs, inbound replication with the source partner is stopped on the destination domain controller and event ID 2042 is logged in the Directory Services event log.

计算机密码学是研究计算机信息加密、解密及其变换的科学，是数学和计算机的交义学科，也是一门新兴的学科。

Instructions: click on the thumbnails to see a larger image, then use the left-right arrow keys to scroll through the slideshow.

使用说明：滑鼠点在小图上即可放大观赏。开启后键盘左右键可用来换照片。