条件梯度法

Higher temperature gradient, larger heat transfer coefficient and proper heat dissipation from the bottom of crucible are necessary for Bridgman method and also important for optimization of growth technique.

5较大的温度梯度，较大的换热系数和适量的底部冷却是坩埚下降法晶体生长的必备条件，也是工艺优化的重要方向。

The OTSU algorithm （maximization of interclass variance） is considered as one of the superior threshold selection methods.But this method can not segment the path mark image successfully for our indigenous design and manufactured vision navigation intelligent vehicle under bright illumination.A new method based on regional Roberts gradient is proposed in order to solve this problem.

OTSU法被认为是图像分割中阈值自动选取的最优方法之一，针对自主开发的视觉导航区域交通智能车辆的导航路径在强光照条件下不能直接应用此方法取得准确分割效果的问题，提出了一种基于区域的罗伯特梯度算子的图像分割方法。

Preconditioned con- jugate gradient algorithm is a fast and accurate computational algorithm.

预条件共轭梯度法是一种精确并且收敛迅速的计算方法。

Its global convergence and linear convergence rate were proved under some mild conditions.

提出一类新的求解无约束优化问题的记忆梯度法，在较弱条件下证明了算法具有全局收敛性和线性收敛速率。

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。

Assuming the independence (or the weak-correlation) between the reflectivity and wavelet, the optimal estimation equations for the wavelet and reflectivity were derived respectively. Furthermore, pre-conditional conjugate gradient algorithm iteration inversion was applied to realize the simultaneous estimation of reflectivity and wavelet.

基于反射系数与子波相互独立的假设，分别构建了反射系数和子波最优估计方程，并采用预条件共轭梯度法迭代反演实现反射系数和子波的同时估计。

A proper k total colouring of a graph G is a colouring to its vertices and edges using k colours such that no two adjacent or incident elements of G may be assigned the same colour.

利用梯度投影与罚函数相结合的技巧，将带不等式和等式约束的优化问题化成一个无约束问题，提出了初始点可任意的求解不等式、等式约束优化问题的摄动梯度投影算法；参数δk取不同的数还可以得到一类梯度投影算法，从而得出了在搜索方向和步长不精确条件下的梯度投影法，保证了在实际应用中更容易实现；在较弱条件下，证明了该算法的全局收敛性。

First, based on quadratic model and Perrys conjugacy condition, two new formulas of the main parameter β_k of conjugate gradient method are proposed.

第一，本文基于二次模型及Perry提出的共轭性条件，导出共轭梯度法的主要参数β_k的两种新形式。

In the article a optical system was developed by the newest RC microscope with the schlieren method, which made the figure of appearance excellent colour and lustre and fine third dimension. The special cylindrical and cubic crystal growth cell was designed and the temperature-control system was developed to cooperate with the cell. Radial thermal gradient was formed in the cylindrical cell while transverse thermal gradient in the cubic cell, which was prepared for finding new effects.

在实验中首次采用最新式的浮雕相衬显微镜和纹影法光路相结合的方法，使得实时观察到的形貌图有良好的色泽和三维立体感；自行设计了柱型和方型两种型号的晶体生长室，研制了适合这两种晶体生长室的温度控制系统，在柱型晶体生长室中形成中心径向的温度梯度，在方型晶体生长室中形成横向的温度梯度，从而为发现新效应创造条件。

The real data verification shows that the wavelet, reflection factor and acoustic impedance given by PCGA are more accurate, quicker convergent and value stable than the existing direct sparse inversion method.

用实际数据检验算法，表明预条件共轭梯度法反演的子波、反射系数和波阻抗要比直接稀疏反演精度高、收敛快、数值稳定。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。