查询词典 spectral function

By adopting relationship in frequency domain coherence analysis method is presented on the thesis for conventional fMRI and resting-state fMRI. Otherwise I use cross spectral density function in the coherence analysis method to discuss the phase delay and phase lead.

本篇论文采用同调性分析的方法探讨频率上相关性的方法研究一般功能性影像与平静状态功能性的影像并藉由同调性分析里交互频谱密度函数来研究信号之间相位差的问题。

The main job and contribution of this paper are as follows:Based on narrowband signal processing, we propose a new method for FH signal blind detection and blind parameter estimation. Firstly, compute the cross-correlation function of FH signals from multichannels, then we get the cross power spectral density matrixCSDM Secondly, select the hops of FH signals from the CSDM via processing and analyzing the CSDM, meanwhile reduce the influence coming from noise, fixed frequency signal and other interferences; Lastly, estimating the DOA of every hop and according to the DOA, we can separate the hops, get the number of FH signals and their parameters. Propose a new method for designing the threshold in FH signal detection. This method makes it easy to get the threshold by theoretic computing and it can extremely reduce the interference of non-FH signals.Based on broadband signal processing, we propose a new method for FH signal blind detection and blind parameter estimation. Firstly, get the DOA of the signals by wideband spatial spectrum estimation; secondly, separate the signals by spatial filtering using wideband beamformer; Lastly, we propose two methods for FH signal blind detection and blind parameter estimation, one is for several constant hop-rate FH signals whose dwell-time are different and another is for a single FH signal whose hop-rate is alterable.By employing spatial interpolation in broadband signal beamforming, it can reduce the number of antenna elements and corresponding RF modules, A/D converters, etc. It can also eliminate the mutual coupling between antenna elements while getting the narrower main beamwidth and lower sidelobe level.

本文的主要研究工作和贡献如下：●提出了一种基于窄带处理的FH信号盲检测和参数盲估计的实现方法，即首先求出多路信号之间的互相关，进而得到互功率谱密度矩阵，然后通过对CSDM进行对折处理来抑制噪声、定频信号及其他干扰的影响，并将所有属于FH信号的hop(每一跳的驻留时间在时频图上持续的线段)从CSDM中筛选出来，最后用阵列信号处理中的到达方向估计理论在频域中估计出各个hop的方向参数，利用方位信息完成FH信号分离并得到FH信号的数目及其各自的参数集；●提出了一种确定FH信号检测门限的策略，该策略不仅使得检测门限能够通过理论计算得到，而且还显著地抑制了非跳频信号的干扰，从而能有效地检测出FH信号；●提出了一种基于宽带处理的短波FH信号盲检测和参数盲估计的实现方法，即首先利用宽带空间谱测向技术得到接收信号的DOA，然后采用宽带波束形成技术对特定方向进行空间滤波，实现多个信号的分离，最后分别提出了两种FH信号的盲检测和参数盲估计方法，第一种方法适用于空间某个特定方向上存在着几个驻留时间不同的恒跳速FH信号和其他干扰信号的混合信号，第二种方法适用于空间某个特定方向上仅含一个可变跳速的FH信号和噪声的混合信号；●将空间插值的概念和宽带波束形成技术结合起来，提出了一种基于频域处理的宽带恒定束宽的波束形成方法。

Within the spectral range of 0.2-1.7 m m and 2.5-12.6 m m, the dielectric function of LaNiO3 film is described by damped oscillation and free electron model, respectively.

在0.2-1.7 m m和2.5-12.6 m m两个波段范围，LaNiO3薄膜的介电函数分别用阻尼振子模型和自由电子模型描述。

With the aid of the spectral decomposition and finite expression formula of matrix we can compute matrix function.

利用矩阵函数的谱分解与有限表示形式计算矩阵函数。

First, a generalized spectral-domain Greens function defining the field inside a multilayer dielectric structure is derived.

本文主要采用谱域矩量法对多层介质微带阵列的辐射特性和交叉极化特性进行分析。

Based on the spectral density function,an efficient and practical method of wind loading simulation is presented.

1引言随着现代材料、施工技术以及设计理论的发展，出现了越来越多柔性的、自重轻、阻尼小的建筑物。

One way is point operation of an image and another is power spectral density function.

经过这些处理，使雷达图像质量较处理前有了很大提高。

Then, the matrix product of them determined the pressure fluctuations＇power spectral density function matrix .

实验还证实了单个气栓内部瞬时压力的均匀性和料栓内部空隙率的不变性。

The Murrell-Sorbie potential energy function curves of diatomic molecule of Au2 Cu2 Y2 AuY and AuCu have been obtained, then the spectral datum and force constants have been derived..

导出了Au_2、Cu_2、Y_2、AuY和AuCu双原子分子的Murrell-Sorbie势能函数，在此基础上推导出光谱项常数和力常数。

Fourier transformation image-processing technology was applied for determining the cross section fiber cell arrangement in hardwood. In this method, the disc-convoluted dot map from each cell radius with 10 pixels was transformed by Fourier transformation, and generated the angle distribution function in the power spectral pattern. The maximum value reflected the arrangement of the fiber cell.

利用傅立叶变换图象处理技术来测定阔叶材横切面纤维细胞排列，把表示每一个纤维细胞的半径为10个像素点的圈盘点图，进行傅立叶变换，再做能量光谱图的角度分布图，其最大值表示纤维细胞的排列。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。