查询词典 gradient method

We have studied a model of a non-Newtonian viscous compressible fluid in 3D bounded domains, in which the viscous part of the stress tensor satisfies the coerciveness condition and the values of the growth condition ., are positive constants. Here is the tensor of the velocity gradient, is the strain tensor and ,which depends on the tensor of the velocity gradient, is the hefts of .

对满足强制性条件，以及增长性条件的非牛顿粘性可压缩流体在三维有界区域中的流动进行了研究，其中和为正常数，为速度梯度张量，是偏应力张量，为的分量，它依赖于速度梯度张量。

It has been deduced that the search direction remains the same but that the step length decreases in optimizing the improved cost function with the conjugate gradient algorithm from the gradient of the cost function that the FIR filter apporaches the contrary point spread function more, and that the estimated image is closer to the original one.

从代价函数的梯度入手推导出共轭梯度算法，其搜索方向保持不变而搜索步长变小，使滤波系数更加逼近于点扩展函数逆算子，从而使估计图像与原始图像更加接近。

The simulation floating zone modelwith zero temperature gradient in the middle of the hot rod is proposed to simulate thehalf part of the full floating zone convection,since the temperature gradient in the middleof a full floating zone approaches zero.

根据加热方式的不同，可以将半浮区液桥分为通常半浮区液桥模型、模拟半浮区模型以及改型半浮区模型。通常半浮区液桥模型，液桥热端材料一般选择为金属材料，使得热端温度分布均匀。液桥产生热毛细对流时，在液桥热端内侧存在较大的轴向温度梯度。而在全浮区热毛细对流中，浮区中间的轴向温度梯度在对称条件下应该接近于零。

In order to mine the structure difference of the chinese and english characters,the gradient information of the pixel based horizontal and vertical stroke vector,gradient orientation correlogram and the relative gray information of the location correlation pixels based census transform histogram are used,they can be robust to illumination,noise and resolution and so on,and can be applied to camera-based images.

为了能够很好地挖掘中英文字符之间的结构差异，提出采用基于象素梯度信息的水平垂直笔画向量和梯度方向相关图，以及基于位置相关象素的相对灰度信息的Census变换直方图，它们对光照、噪声以及分辨率等都具有良好的鲁棒性，可以应用于基于相机的图像。

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 diffusion of mass or heat across two phases is extensively involved in chemical processes. Because of the effect of this kind of diffusion, there will be a inhomogeneous distribution of material concentration and then a gradient of interfacial tension will be occured on the interface of the two phases. When the gradient tends to a certain value, the natural convection would be induced derivatively, and orderly convective cells would appear in the system simultaneously. This is the so-called Marangoni phenomenon.

在化工过程中，广泛涉及到两相间的质量或热量扩散，由于这种扩散的作用，将在相界面处产生物质浓度的不均匀分布，从而出现界面张力梯度，这种梯度达到一定值以后，将出现派生的自然对流运动，并且在系统中呈现有序的对流胞结构，这就是所谓的Marangoni现象。

Taking the gradient property of piezoelectric parameters g-(31),elastic compliance parameters S-(33) and density ρ along z direction into account,some parameter identification methods for a functionally gradient piezoelectric material are studied in the present analysis.

当考虑压电材料的压电参数g31，弹性参数S33和材料密度ρ沿厚度呈梯度变化时，通过测量压电材料悬臂梁在电场或横向集中力作用下梁的宏观反映，给出了确定这些参数分布的公式，包括g31、S33的单参数识别及体积力与联合参数识别的方法。

While these gradients could all be detected reasonably well,we found a slight shift in discriminability in favour of positive gradients and found that surfaces with no gradient at all were more likely to be judged to have a positive gradient.

让被试辨别表面质地密度变化的方向，结果发现被试能够很好地判别表面质地密度变化的方向，但在判别正向变化的表面时显得更准确；当表面密度没有变化时，被试倾向于判别为正向变化。

Based on a Hopfield neural network mode for combinational circuit test generation, a test generation algorithm with global searching ability is proposed. This algorithm is the combination of chaotic searching with gradient algorithm. By means of the inherent stochastic and ergodic property of chaotic searching, the problem of being trapped in local minimum of gradient algorithm can be solved.

基于组合电路测试生成的离散Hopfield神经网络模型，将混沌搜索与Hopfield网络的梯度算法相结合，利用混沌搜索的内随机性及遍历性来克服梯度算法易于陷于局部极小的缺点，形成一种具有全局搜索能力的测试生成有效算法。

Relative positive temperature-gradient applicable for China is discussed, it proves that positive temperature-gradient can be expressed as exponential curve.

研究了我国公路桥梁混凝土箱梁的正温度梯度，证明其可以用指数函数来表达，并提出了本桥混凝土箱梁的正温度梯度指数函数表达式。

You can snipe the second and third union leaders from this position.

您可以鹬第二和第三工会领袖从这一立场出发。

Aiming at the currently shortage of XML streams quality detecting, this paper proposes a new forecasting method of XML streams quality by least squares support vector machines, which is used the method of XML keys' vector matrix as windows, and vector product wavelet transform to multilevel decompose and refactor the XML streams series, that can fulfill real-time checking demand of XML quality, and ensure constraint, consist- ency and integrality. For even more adapting net load, it proposes a control strategy by weight and adaptive adjustment to ensure XML streams quality.

针对当前XML数据流质量检测存在的不足，提出构建XML键的矢量矩阵作为窗口，利用矢量积小波变换多级分解与重构XML数据流，再结合最小二乘支持向量机对XML数据流质量进行预测的一种方法，满足XML数据流质量重构时实时检测的要求，保证XML数据的约束性、一致性与完整性；为了更好的适应网络负载，采取加权与自适应窗口调整等调度策略充分保证XML数据流的质量检测。