基于Michelson干涉原理的光纤加速度计的研究

分析了一种迈克尔逊干涉型光纤加速度计的结构设计和工作原理,详细推导了被测信号的加速度与迈克尔逊干涉仪的输出相位差之间的关系,并对加速度的灵敏度进行了相应的参数讨论,最后应用Matlab软件对光信号处理电路进行了仿真;结果表明,解调信号和待测信号相位一致性好,从而从理论上证明了这种结构新颖、体积小、精度高、成本低的干涉型光纤加速度计是合理可行的.     

基于相位生成载波的全光纤传感器定位研究

分布式光纤传感系统可应用于长距离、强电磁干扰环境下的监测.提出了一种用相位调制器进行外调制来提高分布式光纤传感器定位精度的方法.构造基于迈克尔逊干涉仪的全光纤振动传感器系统,并在反射端加相位调制器进行调制,使经过反射端反射的光干涉后的信号处于高频段,而未经反射端反射的光干涉后的信号处于低频段.通过高通滤波和相位解调,获得与外界扰动呈正比的信号,用这一信号进行定位,可以消除因为光纤中的瑞利散射等产生的回光干涉信号的频谱叠加,提高定位精度.该方法结构简单,易实现,通过理论分析和实验证明:采用该方法可以有效提高系统的定位精度.     

双光路迈克尔逊加速度检波器

研制了一种实用的双光路全光纤迈克尔逊加速度检波器.与单光路结构相比,双光路检波器频带更宽,而且可以实现对检波器敏感元件的横向振动、倾斜和弯曲更好地限制.系统主要包括单模全光纤迈克尔逊干涉仪、简谐振子、信号处理系统.在信号处理过程中采用了交流相位跟踪零差补偿技术(PTAC).实验结果与理论相符合,实测工作频带为0～515 Hz.     

基于迈克尔逊干涉原理的光纤传感器简述

摘要：从基于迈克尔逊干涉原理的光纤迈克尔逊干涉仪出发,介绍了光纤迈克尔逊干涉仪系统原理,并分析了干涉仪的工作原理。在此基础上,针对一些对仪器产生影响的问题提出简略的解决方法,同时阐述了此系统的优点以及应用。     

基于FPGA的静态实时光谱采集与处理系统

为了实时获取静态迈克尔逊干涉仪得到的光谱信息,设计了基于FPGA的实时光谱采集分析系统。在Xilinx FPGA芯片上实现了干涉条纹到光谱数据的实时处理。在算法处理过程中,实现了干涉条纹滤波去噪、快速傅里叶变换、相位标定、光谱数据传输等模块化功能。实验结果显示,系统可以高速采集并实时处理光谱数据。     

干涉型光纤传感器解调方法改进与研究

通过分析光纤干涉仪输出信号成分和理论推导,提出了干涉型光纤传感器相位生成载波(PGC)调制解调技术的改进方案,通过实验仿真得出,新方案不需要AGC模块就可以消除干涉仪输出光功率漂移对解调结果的影响,而且系统的最低采样频率减低了约1/3.     

新型迈克尔逊干涉条纹测控装置研制

为减小背景光的影响,传统的迈克尔逊干涉试验需要在黑暗中进行,不便读取毫米刻度尺、粗调鼓轮读数窗口和微调鼓轮读数窗口的读数。而人工计数需要长时间盯着观测屏计数,容易因眼睛疲劳、视野模糊而导致计数误差。为此,设计了一种新型迈克尔逊干涉条纹测控装置。该装置以上位机为核心,结合单片机、步进电机驱动器和步进电机控制迈克尔逊干涉仪读数鼓轮转动,实现了可动反射镜的移动;利用采集卡、硅光电池、电压信号放大器等测量干涉条纹圆心处的亮度;通过调整采集周期,消除步进电机抖动对试验测量的影响;利用条纹圆心处的光强变化与可动反射镜移动距离之间的关系,计算激光波长。试验结果表明,新型迈克尔逊干涉条纹测控装置可以代替人眼进行读数和计数,在解决试验人员条纹计数困难的同时,消除了条纹计数误差的影响、提高了测量的效率和准确性。该装置可用于测量光波波长、微小位移、薄膜厚度、介质折射率和线胀系数,以及研究温度和压力对光传播的影响。     

基于压电陶瓷相位调制器的外调制相位生成载波法研究

对基于压电换能器PZT(Piezoelectric Transducer)的外调制相位生成载波PGC(Phase-Generated Carrier)法进行了深入的理论分析和实验研究.PZT光纤相位调制器利用电致伸缩效应来改变缠绕在其上面的光纤的长度,进而实现对光纤中光相位的周期性调制.在马赫曾德尔光纤干涉仪MZI(Mach-Zehnder Interferometer)的参考臂中加入该光纤相位调制器便可以将载波信号调制到光纤干涉仪的输出信号当中.计算机仿真分析了调制参数对PGC解调结果的影响.并通过实验验证了这种调制解调方案的可行性.利用美国国家仪器公司的数据采集系统及Labview编写的解调算法,在臂长为200 m的MZI中成功实现了相位解调,恢复出MZI传感臂中的原始相位信息,解调信号与原始信号的相关系数在0.99以上.     

基于激光干涉仪的角度测量技术

介绍了一种基于激光干涉技术的精密角度测量系统 ,该系统利用干涉仪在几何量测量中的干涉测量技术 ,以激光作为干涉光源 ,迈克尔逊干涉仪作为干涉测量装置 ,通过角度转换装置将角度量转换为可以反映干涉光路中光程差变化的线位移量 ,由此引起干涉条纹的变化 ,再通过相应电路对干涉条纹进行一系列处理 ,从而实现了对大转角的精密测量。与以往类似系统相比 ,该系统具有结构简单、误差恒定、测量精度高、测角范围大、易于数字化等特点     

超磁致伸缩作动器激光干涉位移测量系统

由于超磁致伸缩作动器的位移在微米级,对其精确测量至关重要,针对激光干涉测量技术中分立元件迈克尔逊激光干涉仪存在环境要求高、调整烦琐和易受干扰等缺点,采用全光纤迈克尔逊干涉仪简化测量前的准备工作;并借助高性能动态信号采集卡,配合LabVIEW图形化编程工具,应用贝塞尔函数干涉条纹细分技术提高测量精度,开发了超磁致伸缩作动器位移测量系统。实验证明测量误差与理论计算相符,表明测量结果是准确可靠的。该系统适用于超磁致伸缩作动器位移的实验研究和现场测量,可为微位移的测量提供一种参考方法。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

A human-computer interface for non-computer specialists

The COM teleconferencing system was designed to be easy to use for both beginners and people with much computer experience. A number of design choices in organizing the human-computer interface were considered very carefully. These design problems are not unique for teleconferencing applications, but will appear in many other developments of human-computer interfaces for non-computer specialists. This report discusses naming conventions, menu format, user commands, help facility and the treatment of ‘type ahead’ from the users.