查询词典 spectral

A geometric structure representation of images based on the angle between spectral coefficient vectors of Laplacian graph was proposed. Graph clustering of spectral features was also investigated.

提出一种用拉普拉斯图的谱系数夹角谱特征来描述图像几何结构的方法，同时研究了基于图的谱聚类系统。

The spectral element method, which combines the high-order precision of spectral methods and the geometrical flexibility of finite element methods, has achieved great success and is becoming a useful tool for investigation of such equations.

谱元法作为一种高阶的数值方法，结合了谱方法的高精度和有限元法灵活的网格剖分技术，在不可压流体的计算中已取得了很大的成功，并正成为计算随机微分方程的一个有力工具。

Considering that as the spectral resolution of hyperspectral images increases, its spectral correlation becomes more and more significant, a group of prediction coefficients are derived, which are able to make use of multi-band to predict the current band linearly. And then a fast algorithm is given to solve the coefficients of the predictor.

首先，充分考虑到随着高光谱图像谱间分辨率的提高，其谱间相关性也越来越强烈，推导出由多个波段对当前波段做线性预测的预测器系数，然后给出快速计算求解预测器系数的算法。

The axial direction and radial direction spectrum is blue-shift or red-shift. On axial direction, the blue-shift or red-shift increases with the relative propagation distance, truncation parameter, refractive index constant increases and temporal coherence length decreases, and the spectral-shift gurgitation becom gragually steady. On radial direction, spectral switches appear, and the truncation parameter, spatial coherence parameter, temporal coherence length and refractive index constant also influence critical position and transition height et al.

光谱沿轴向、径向均出现蓝移或红移，随着相对传输距离、光阑截断参数、空间相干参数及折射率结构常数的增大，脉冲时间相干长度的减小，轴向光谱蓝移量或红移量逐渐增大，并且由明显地起伏逐渐趋于稳定，沿径向出现了光谱开关，光阑截断参数、脉冲时间相干长度、空间相干参数和折射率结构常数对光谱开关的数目、光谱开关的临界位置和光谱跃迁量等也产生影响。

Starting from the polarization matrix and propagation equation of the cross-spectral density matrix, a detailed study of the influence of hard-edge aperture on the spectral switch of polychromatic vector Gaussian-Schell model beams is performed.

从偏振矩阵和交叉谱密度传输公式出发，分析了硬边光阑对多色矢量高斯－谢尔模型光束轴上光谱开关的影响。

The method comprises the following steps of : respectively constructing models of residual images of a multi-spectral image and a panchromatic image by using hypercomplex, and respectively subjecting the hypercomplex residual models of the multi-spectral image to hypercomplex symplectic decomposition along the grayscale axis direction to obtain a simplex portion containing brightness information and a perplex portion including chromaticity information.

该方法首先用超复数分别对多光谱图像和全色图像的残差图像建模，并对多光谱图像的超复数残差模型沿灰度轴方向分别进行超复数symplectic分解，得到包含亮度信息的simplex部分和包含色度信息的perplex部分。

Firstly, applying spectral factorization to minimize an integral square performance criterion containing tracking error and control energy, an optimal control law for the nominal model is derived on condition of control energy constraint. Then, for model uncertainty, using spectral factorization to minimize the variance of the actual system performance from the nominal performance over all frequency range, a robust controller design method is abtained, which has optimal robustness of the system nominal performance to model errors.

首先针对控制对象的标称模型应用谱分解最小化一个包含跟踪误差和控制能量在内的积分平方性能指标，导出一个控制能量约束条件下的最优控制律；然后再针对模型不确定性应用谱分解最小化实际系统性能和标称性能在整个频段上的方差，得到一个鲁棒控制器的设计方法，可使系统的标称性能对模型误差具有最优的鲁棒性。

The main contents include: Some preliminary theory (introduction to Sobolev spaces and variational formulations for differential equations); finite element methods for one-dimensional elliptic problems; the construction methods for general finite elements; error estimates for interpolation operators and inverse inequalities for finite element spaces; a priori and a posteriori error estimates for the finite element method for high-dimensional elliptic problems; some typical spectral methods for partial differential equations; error analysis for the spectral approximation for some linear and nonlinear partial differential equations.

主要内容有：准备知识（Sobolev空间的基本概念和主要结果，微分方程的变分描述）；一维椭圆型方程有限元方法；一般有限元的构造；插值算子误差估计和逆不等式；高维椭圆型方程的先验、后验误差估计；求解偏微分方程的几类谱方法；线性与非线性问题谱逼近的误差分析等。

So it is very important to found a higher accuracy standard of spectral irradiance and spectral radiance.

因此建立一个高精度的光谱辐照度和光谱辐亮度标准是非常必要的。

Established a series of results on the Jacobi approximation, and proposed the Jacobi spectral method for singular problems, which produces the possibility of using spectral mcthod for problems in a ball.

最近，郭本瑜教授等建立了一套相当完整的Jacobi正交逼近理论，并提出了适合于一类奇异问题的Jacobi谱方注。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。