principle half-power beamwidths

A novel method based on the Graham scan is proposed to extract the chief wave of the spectrogram envelop, while an improved angle detection method is applied to recognize the features.

基于格雷厄姆扫描算法提出声谱图包络主波提取的新方法,并用改进的角度探测方法进行包络特征的识别。

The results show that two particular and wide absorption bands,band a1 (425～428 nm) and band a3(693～688 nm),are present in Qingu turquoise samples,and the dominant wavelength and purity of the visible absorption spectrum are corresponding to the colour characteristics.

采用USB2000微型光纤光谱仪测试了湖北秦古绿松石样品的可见吸收光谱,结果表明,该样品在可见光范围内存在a1(425~428 nm)和a2(683~688 nm)两处特征的吸收宽谱带,其可见吸收光谱主波长和纯度的变化与颜色特征具有一定的对应关系。

By using the PUV method,a method to compute wave directional spectrum with observed pressure and current vectors,the wave directional spectrum can be calculated and the dominant wave direction is then obtained.

海洋水文多参数测量仪是南海海洋研究所新研制的一种可以同步测量海流、波浪、潮位、水温、电导率的仪器,利用同步观测压力和矢量流速估计海面方向谱的方法(PUV方法)可以计算得到海面方向谱,进而求得主波向。

The system is divided into six parts, which are central waveguide, coupling, detector, filter, connection and test results.

本文设计的波导功率传输组件为总装部合同项目,应用于某型号导引头系统中,起到功率的传输、滤波检波及监控作用,其结构包括了主波导传输、耦合机构、检波和滤波部件等。