An active microphotodiode array of oscillating pixels for retinal stimulation

We have developed an active microphotodiode array (MPDA) for retinal stimulation. The unique feature of the device is that each pixel acts as an independent oscillator, whose frequency is controlled by the incident light intensity. The design is based on a double inverter relaxation oscillator, and the photodiodes are of PIN-type. These oscillating pixels stimulate the nervous tissue with bipolar pulses. The prototype stimulator chips are realized in standard 0.35 μm CMOS technology. The reported preliminary data and performance demonstrate the potential of the new concept for future retinal prostheses.     

Estimator-correlator array processing: Theoretical underpinnings and adaptive implementation

We develop a generalized singular value decomposition methodology for implementing the estimator-correlator array processor. The usefulness of this structure stems from two key properties examined in this paper. First, the structure is canonical, in that it applies to a broad class of underwater signal processing problems. Second, it is robust, not critically dependent on a precise characterization of the medium in question. Numerical simulation experiments justifying this claim are presented.Specific examples demonstrate the general implementation procedure. Although the results are computationally demanding, they can in large part be realized with parallel architectures. Hence, their implementation by dedicated processors is possible.     

MAMA紫外探测器系统与高增益MCP（三）

介绍了多阳极微道板阵列（ＭＡＭＡ）紫外探测器系统的最新结构与性能，以及高增益ＭＣＰ工作的基本特性，并给出了对各类高增益ＭＣＰ测试的结果。     

气枪震源的发展与使用分析(上)

本文从气枪震源的发展入手,对各类气枪的性能、参数和工作原理进行了分析比较,列出了各类气枪的常用阵列。分析出了影响气枪参数的因素,并给出了气枪充气时间的计算方法及气枪阵列的设计方法。     

基于针孔阵列的多光束共焦三维测量系统

提出了一种基于 5 0 0× 5 0 0的针孔阵列的多光束共焦三维测量系统 ,该系统具有测量视场大 ,测量速度快 ,系统结构简单等特点     

Operation of NIST Josephson Array Voltage Standards

This paper begins with a brief discussion of the physical principles and history of Josephson effect voltage standards. The main body of the paper deals with the practical details of the array design, cryoprobe construction, bias source requirements, adjustment of the system for optimum performance, calibration algorithms, and an assessment of error sources for the NIST-developed Josephson array standard.     

傅立叶变换法数字波束形成研究

文中研究平面相控阵天线数字多波束形成．根据数字波束形成（DBF）原理，进一步得到傅立叶变换数字多波束形成理论，进行了仿真实验．并定性分析了数字多波束的特点。     

基于声场预报的共形阵波束优化方法与实验研究

在工程实际中，声接收基阵波束设计和优化的一个重要问题是实际阵列流形的获取。由于实际测量阵列流形的工作面临很多困难，难以推广使用，本文提出声场预报的方法，使用ANSYS和SYSNOISE软件模拟测量阵列流形的过程，通过对复杂结构基阵的声场进行数值预报，得到了与实际相符合的基阵阵列流形，并通过共形阵水池实验验证了该方法的有效性。     

全对称结构线圈系响应特性分析

常规双感应测井仪传感器存在不能兼顾径向探测深度和纵向分辨率且结构复杂的缺点。文章介绍了一种全对称结构线圈系，对称分布的发射和接收线圈参数相同，保证了线圈系的纵向响应完全对称。计算出了其深／中感应线圈系的纵向、横向几何因子曲线和空间频域响应曲线，并以此为基础对其响应特性进行了讨论。结果表明，该线圈系结构简单，技术指标优良，可以兼有较大的径向探测深度和较高的纵向分辨率。