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The analysis on soil spectral data obtained from the different area of our country shows that exists a soil spectral line in 2-dimension space or multidimension space, but it is not a strictly straight line, it is a belt with certain width.

中文摘要：通过对我国各地的土壤光谱反射率的分析表明，无论在二维或多维空间中，确有土壤光谱线存在，但不是严格的一条直线，而是有适当宽度的带。

Its discretization is based on spectral elements in space and central differences method in time. The numerical result, shows that this approximation has spectral accuracy in space and up to second-order in time.

该解法引入一阶Clayton-Engquist-Majda吸收边界条件，在空间上利用谱元方法，在时间上利用中心差分的积分方法得到波动方程的离散形式，并给出具体算例进行了验证。

The best training samples are searched and selected on the whole image by the local space information and spectral matching, and then they are purified on spectral domains.

利用影像的空间信息在图像局部范围内自动搜索和选择最佳样区位置，再用光谱匹配对寻找到的最佳样区在光谱空间上进一步纯化。

In combination of rough set theory and the distribution information of the land cover spectral feature space,a spectral feature neighborhood based tolerant rough set classification method is proposed to handle the uncertainty in the process of satellite remote sensing data classification.

结合粗糙集理论和遥感数据中地物光谱特征空间分布信息，提出了一种基于光谱特征邻域的容差粗糙集分类方法，用来处理卫星遥感数据分类中的不确定性问题。

Through analyzing the influence of the learning samples' location in the spectral space on the accuracy of multi spectral remote sensing image classification using BP neural network, a method for learning samples selection based on x 2 distribution was presented and used in TM image classification.

通过分析多光谱遥感图像学习样本在光谱空间不同位置对BP神经网络分类器分类精度的影响，提出基于x2 分布的学习样本选取方法，并应用于TM 图像分类。

By taking a plan grating as a beam splitter and a spherical mirror as an imaging objective,the splitting system realizes a spectral plane and a small spectral band(＜42%),which is conductive to the signal receiving by a CCD detector.

分光系统采用平面光栅为分光元件，球面反射镜为成像物镜，实现了平谱面和较小的谱线弯曲(＜42%)，利于CCD探测器接收。

Our results improve the former results. For periodic Jacobi matrix, some new spectral properties of periodic Jacobi matrix are given by studying the relationship of the eigenvalues of periodic Jacobi matrix and its n—1 principal submatrix. Applying these spectral properties, we present a necessary and sufficient condition for the solvability of an inverse problem of periodic Jacobi matrices and discuss the number and the relationship of its solutions. Furthermore, we propose a new algorithm to construct its solution and compare it with the former algorithms. As this inverse problem of periodic Jacobi matrix usually has multiple solutions as many other eigenvalue inverse problems, we study the uniqueness of this problem. And a necessary and sufficient condition is given to ensure its uniqueness, under which an algorithm is presented and the stability analysis is also given. Finally, we put forward a new inverse problem for periodic Jacobi matrix which has not been solved.

对周期Jacobi矩阵特征值反问题，通过研究周期Jacobi矩阵与其n-1阶主子阵特征值的关系，给出了周期Jacobi矩阵的一些新的谱性质；利用这些谱性质，研究了一类周期Jacobi矩阵特征值反问题，用新的方法推导出了该类特征值反问题有解的充分必要条件，并讨论了解的个数以及解与解之间的关系；此外，提出了一种新的构造周期Jacobi矩阵反问题解的数值算法，并与前人的算法做了一定比较；由于周期Jacobi矩阵特征值反问题和其他很多特征值反问题一样往往存在多个解，本论文给出了周期Jacobi矩阵反问题解唯一的充要条件，并发现周期Jacobi矩阵特征值反问题的解唯一当且仅当构造的矩阵满足一定的条件；在解唯一的情况下，给出了构造唯一解的数值算法，并做了相应的稳定性分析；最后，提出了一类新的有待于解决的周期Jacobi矩阵特征值反问题。

Spectral efficiency equations are derived for both systems with and without channel prediction. Numerical results show that systems with channel prediction can get maximum spectral efficiency while systems without channel prediction but chosen optimum packet length can get suboptimum frequency efficiency, which is inversely proportional to Doppler frequency.

推导了信道预测和没有信道预测的自适应调制系统的频谱效率公式，分析结果表明对于自适应调制系统，信道预测的系统频谱效率是最优的，非信道预测系统根据信道情况选择最优帧长可以获得该系统的最优系统频谱效率，但它是低于信道预测的频谱效率的，而且是随多普勒频率的增大而逐渐减小的。

Laser Raman spectral technique is an important section in modern laser spectral techniques. Laser Raman spectrum plays an important role on the aspects of analyzing molecular structure, symmetry properties of crystal, investigating solid structure phase-variation and the structure of IR spectrum of molecule. In recent years,it has been extensively applied in many research fields such as organic and inorganic analytical chemistry, biochemistry, petrochemical industry, macromolecule chemistry ,etc.

激光喇曼光谱技术是现代激光光谱技术中的一个重要组成部分，激光喇曼光谱对于确定分子结构和晶体的对称性、研究各种固体结构相变及红外光谱结构分析等方面具有重要作用，近些年来已经广泛地应用于有机和无机分析化学、生物化学、石油化工、高分子化学等领域。

Burg maximum entropy spectral estimation theory of modern spectral estimation is introduced in this paper, and the PSD is simulated by VC ++.

介绍了现代功率谱估计中的Burg算法最大熵谱估计的基本原理，并采用VC++语言对功率谱密度进行了仿真。

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％。