Ground-state complex formation of perylene with pyromellitic dianhydride studied by static fluorescence quenching

The association of complex formation with static quenching in CT systems was investigated. Evaluation of the data made evident that the inner filter effect must be allowed for. Time-resolved and temperature-dependent stationary measurements of fluorescence led to the separation of dynamic and static quenching components. The static quenching constant is discussed with respect to the equilibrium constant of complex formation determined by absorption spectroscopy.     

声表面波滤波器的匹配电路设计

介绍了通过测试仪器采集的声表面波（SAW）滤波器的Sij(i,j=1,2）参数来优化匹配电路的方法。首先将采集的Sij(i,j=1,2）参数转换为SAW滤波器Yij(i,j=1,2）参数，然后建立新的S12（或S21）参数与匹配电路的依赖关系，通过优化匹配电路元件值，而使滤波器的插入损耗和通带波动满足目标值，该方法的主要优点是考虑整个通带特性，而不是考虑通带内的某一点（如中心频率）。     

Adaptive remeshing for ductile fracture prediction in metal formingRemaillage adaptatif pour la prévision de la rupture ductile en mise en forme

The analysis of mechanical structures using the Finite Element Method in the framework of large elastoplastic strain, needs frequent remeshing of the deformed domain during computation. Indeed, the remeshing is due to the large geometrical distortion of finite elements and the adaptation to the physical behavior of the solution. This paper gives the necessary steps to remesh a mechanical structure during large elastoplastic deformations with damage. An important part of this process is constituted by geometrical and physical error estimates. The proposed method is integrated in a computational environment using the ABAQUS/Explicit solver and the BL2D-V2 adaptive mesher. To cite this article: H. Borouchaki et al., C. R. Mecanique 330 (2002) 709–716.     

合成孔径雷达干扰技术的研究

合成孔径雷达（Synthetic Aperture Radar）是一种新型高辨力成像雷达。其在距离上利用发射的线性调频（LFM）的脉冲压缩信号来获取距离上的高分辨力，在方位上利用接收脉冲之间的多普勒信息获得方位上的高分辨力。本文在简单分析合成孔径雷达工作原理基础上，针对合成孔径雷达的特点与弱点，讨论了几种干扰样式。     

一种MPEG2视频编码的神经网络自适应量化算法

本文在ＭＰＥＧ２ＴＭ５建议我自适应量化策略的基础上，提出了一种ＭＰＥＧ２视频编码的神经网络自适应量化算法。     

一种遗传-梯度混合算法

本文提出一种函数全局优化的遗传-梯度混合算法。该算法由选择、交叉和诱导变异算子组成。通过对自适应滤波和前向神经网络权值训练两个典型问题的数字仿真，表明该算法是一种快速有效的全局优化算法。     

A NEW ALGORITHM FOR ADAPTIVE LATTICE FILTERAND ITS APPLICATION IN THE SPEECH LINEARPREDICTIVE SYNTHESIS

In this paper, an adaptive line spectral pair filter is derived from an adaptive lattice filter. A least-mean-square(LMS) type adaptive algorithm used to calculate directly the line spectral pair(LSP) coefficients on a stage-by-stage basis is presented. Experimental results show that the algorithm has higher convergence rate and lower misadjustment as compared with the other algorithms. The LSP coefficients calculated by the algorithm have been used to carry out speech linear predictive synthesis, resulting in better results than PARCOR coefficients.     

高阻带抑制有源声表面波滤波组件

介绍有源声表面波滤波组件的设计思路。报道最新研制的高性能滤波组件，其中心频率４０ＭＨｚ，３ｄＢ相对带宽０．８％，阻带抑制优于１００ｄＢ，矩形系数（Δｆ１００ｄＢ／Δｆ３ｄＢ）小于３，输入输出端口电压驻波比接近１。组件体积８５ｍｍ×３５ｍｍ×２４ｍｍ，重量小于１１５ｇ     

阵列天线在OFDM系统下行链路中的应用

正交频分多址(OFDM:orthogonal frequency division multiplexing)技术由于其在多径环境下克服码间干扰的固有特点,在移动通信中已得到广泛地应用。利用阵列天线上行链路信号到达角估计实时信息,计算OFDM系统下行链路阵列天线权重,将阵列天线应用于下行链路中,最后给出系统误码率性能的计算机仿真结果。     

基于CCD采集的Mach-Zehnder干涉条纹图的处理算法

Mach-Zehnder干涉仪适用于研究气体密度迅速变化的状态。由于气体折射率的变化与其密度的变化成正比,而折射率的变化将使通过气体的光线有不同的光程,因此可通过干涉臂变化对干涉条纹图像效果的影响得到气体密度。实测中,采用图像采集卡和CCD来接收Mach-Zehnder干涉仪产生的条纹图像,再通过计算机对条纹图像的条纹间距进行处理,从而得到气体密度的变化状态。从光干涉理论出发,对Mach-Zehnder干涉条纹图像特征进行了分析,建立了Mach-Zehnder干涉条纹的数学模型,并根据此模型设计了处理Mach-Zehnder干涉条纹图像的算法。算法包括图像的预处理(即图像的噪声提取)、图像的二值化及图像的细化。