查询词典 spectral analysis

This thesis is divided into six parts. The first chapter is preface, the current status of research in the inverse problems for parabolic partial differential equations is reported; the second chapter is "regularization methods for numerical differentiation and their applications ", in this chapter we investigate many regularization methods from a viewpoint of regularization theory and algorithm, some applications in the inverse problems for parabolic partial differential equations are given; the third chapter is "spectral regularization methods". Based on Fourier analysis, within the framework of regularization theory, we apply the spectral methods to some ill-posed problems. Many numerical experiments are done in order to show the validity of the methods; the fourth chapter is devoted to wavelet dual least squares method and a revised wavelet method; in the fifth chapter,we combine finite difference method with method of lines and apply it to the backward heat conduction problem in time; in the sixth chapter "identification problems for unknown source ", the essence and the degree of two problems related to source identification are pointed out, at the same time, some numerical methods are reported.

本文分为六个部分，第一章前言简要分析了国内外抛物型偏微分方程反问题的研究现状；第二章数值微分的正则化及其应用从正则化理论和算法的角度出发，考察了许多正则化方法，还给出了数值微分在抛物型偏微分方程反问题的一些应用；第三章谱正则化方法是在Fourier分析的基础上，在一般正则化理论的框架下，给出了这种方法在各种不适定问题中的应用，数值实验表明谱方法是有效的；第四章研究了小波对偶最小二乘方法和改进的小波方法；第五章主要研究了有限差分方法结合线方法在时间反向热传导问题中的应用；第六章是未知源识别问题，主要指出了两类未知源问题的不适定程度和不适定本质，同时报告了一些数值方法。

Wavelength calibration coefficients were calculated through regression analysis after several ordinal numbers of CCD's pixels corresponding to Mercury-Argon Lamp's spectral lines were measured. The residuals of certain spectral lines were computed using the coefficients measured and the ones from factory, the degree of fitting for regression equation was estimated using the new coefficients. The final results validated the wavelength calibration model.

在测量了多条光谱线对应的CCD像元的序数之后，使用回归分析得到波长定标的系数，连同光谱仪出厂时的波长定标系数，计算出了两组定标系数在给定的一些谱线位置处的残差，并利用实验所得的系数对回归方程进行了拟合优度检验，结果表明波长定标模型是有效的。

According to the computational stability analysis conducted to the linear term time difference scheme in simple harmonic motion equation, one new semi-implicit integration scheme also is designed. By adopting a kind of revised time-explicitdifference scheme to these linear terms still included in spectral model governing equations, this defect of spectral model only partly used in semi-implicit integrating scheme, can be overcome to some degree.

以简谐振动方程中线性项时间差分格式对其计算稳定性影响为理论依据，本文设计了一种新谱模式半隐式时间积分方案，此方案通过对一般谱模式求解框架中那些隐含的线性项采用了一种显式修正的差分格式，可有效克服其国际谱模式半隐式时间求积方案实质上只是部分应用了半隐式差分格式的问题。

The analysis of deformation series, of spectral response function and of spectral density in the frequency domain.

8在变形序列的频域分析中，主要对表征序列的频时域特性函数一频谱响应函数和频谱密度进行分析。

Using remote sensing software Envi to pretreatment and transform spectral data in order to highlight the nuances of spectral data to the comparative analysis.

使用Envi遥感软件对光谱数据进行预处理及各种变换以突出光谱数据的细微差别，这有利于光谱数据的对比分析。

By analyzing the quantity relationship between spectral property and sandy land,the variation rules of spectral property of surface features were found,and thus the evidence was provided to the extraction and quantitative analysis of sandy land in respect of spectrum.

分析地物光谱特征与土地沙化间的数量关系，找出地物光谱特征变异的规律，从地物光谱的角度为遥感影像中沙化土地提取和定量分析提供依据。

White spectral OCT is set up on partial spectrum analysis,the system chooses required white light source and receiving spectral. It would have more detection depth, higher resolution and improving signal to noise ratio.

建立了基于子光谱分析的白光频域OCT，该系统通过选择所需要的白光光源及其接收频段，这样既可以兼顾最大探测深度和高轴向分辨率，并且提高信噪比。

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。

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。

Discussed element of the matrix in alloy of nickel radical high temperature through the experiment, advocate quantity element if the chromium, cobalt, tungsten, molybdenum, Tantalum, niobium, rhenium spectrum to spectral line of boracic ultimate analysis violates a condition, use matrix to match a law to undertake to matrix interference corrective, fixed appropriate analytic spectral line.

通过试验探索了镍基高温合金中基体元素，主量元素如铬、钴、钨、钼、钽、铌、铼等对硼元素分析谱线的光谱干扰情况，采用基体匹配法对基体干扰进行校正，确定了合适的分析谱线。

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％。