查询词典 cross-section

The influence of the cross—fire of signals in the LSSDV three—beam measuring model is analysed in detail. According to the characteristics of the model, the idea that arranging optical system and receiving system properly so that the cross—fire of signals can be neglected is presented.

详细分析了LSSDV三光束测量模型中信号串扰影响问题，根据该模型的特点，提出了适当布置光学系统和接收系统的位置，可以忽略信号串扰影响的新见解。

Broken cross rate cross-reference clause A clause in a Bank loan document referring to a loan by a commercial bank.

相互参照条款世界银行贷款文件中参照一项商业银行贷款的条款。

The reaction over potential is lower and the direction of electroosmosis and methanol cross over is opposite,so the rate of methanol cross over is reduced.

与气体燃料相比，甲醇易于储备与运输，能量转化效率高，反应产物主要是水和少量的二氧化碳，是环境友好的绿色能源。

Cross ratio is an essential invariant related to projective transformations,and discovering intrinsic properties of scene by using invariance of cross ratio computation is one of the hotspots in computer vision fields.

1引言交比是一个和射影变换有关的一个基本不变量，它的透视不变性已经引起了计算机视觉研究人员的重视，人们利用它从透视图像中进行物体识别[1][2]。

Research on calibration of cameras based on cross ratio invariability ;2. Firstly,order radial lens distortion parameters are computed by using cross ratio invariability .

该方法利用透视投影的交比不变性原理标定镜头的畸变系数，基于摄像机成像的单应性矩阵及内部参数的基本约束，线性标定出其他摄像机参数。

Due to the special relation between cross–strait, should there be "distance" or "reinforced contact" for the economic and trading activities between cross–strait?

由於两岸特殊的关系，两岸经贸关系究竟是应「保持距离」，还是要「加强联系」？

Each Kago consists of a Shoulder Pole, Cross Bars and a Seat on which the Traveller Robot sits and Ropes that attach the Seat to the Cross Bars.

3.2轿子由一个扁担，交叉横条，搭载旅行机器人的底座和连接底座和横条的绳索组成。

A method of cross power spectral density between responses is derived and a poly reference modal analysis method using cross power spectral density method in frequency domain is presented in this paper.

对各测点响应的互功率谱密度函数进行了详细推导，提出了一种基于互功率谱密度的频域多参点辨识法，这意味着许多原本利用频响函数的传统频域识别法可以很容易地用于工作状态下的模态识别，大大开阔了未知激励下模态识别的视野。

PSD method for identifying cross power spectral density of distributed excitation force is discussed by calculating cross power spectral density of measured response.

功率谱密度函数识别法则是以系统反应之交叉功率谱密度函数识别外力之交叉功率谱密度函数。

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。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。