基于B/S模式的网络化监控系统研究

针对嵌入式网络化数字视频监控系统,结合嵌入式技术的现状和发展趋势,提出了基于B/S模式的网络化监控系统总体设计方案。设计了相应的接口和外围电路,搭建了系统的硬件平台和软件平台,进行了嵌入式Linux操作系统的移植,交叉编译环境的建立,以及嵌入式软件开发平台的建立。构建了基B/S模式的网络化监控系统原型,并根据所设计的实验方案,对系统进行了详细的测试。实验表明基于B/S模式的网络化监控系统平台成功实现了通过网络对嵌入式设备的远程访问,并且能够通过Web网页对远程监控设备进行控制。     

基于RTP/RTCP的塔机远程实时监控系统设计与实现

塔机远程安全监控模型容易受到电缆线或无线电信号的限制,大大降低塔机信号传递距离和质量,导致传统的塔机监控模型信号仅能传递几十米到几百米,无法实现塔机的远程实时监控,设计并实现了一种基于RTP/RTCP的智能塔机远程实时监控系统,采用基于C/S与B/S结合的数据链驱动无缝集成模式,设计了智能塔机远程监控模型,实现了各模块间的网络传递,主要包括嵌入式监控终端、中心服务器以及远程客户端3个模块,对中心服务器和客户端采用RTP/RTCP实现视频传递,设计了基于Ajax的Web交互式人机界面,对大规模网络数据进行实时处理分析,最终完成了塔机远程实时视频传输的过程;实验结果说明,所设计模型能够实现塔机的远程实时智能监控,具有较高的监控效率和精度。     

ARM和ZigBee的智能家居监控网络设计

提出了一种智能家居监控网络系统,该系统以ARM微处理器S3C2440为核心,采用浏览器/服务器和客户端/服务器模式,对外通过Internet局域网和无线局域网接入公共网络,在家庭内部通过基于德州仪器C2530无线收发芯片的ZigBee无线网络将家用电器与其他监控设备连接在一起组成无线家庭网络;通过Windows客户端或Web浏览器可以对家庭内部或家用电器进行状态查询和控制,在户内可以使用手持设备,基于Android系统客户端对家用电器进行控制和管理;实际测试结果表明,系统组网方便快捷、运行稳定可靠,能够达到智能家居系统的一般应用要求。     

分布式光伏充电站Web实时监控平台设计

随着光伏充电站基础设施的广泛建设,为电动汽车用户提供便利的同时,也为其管理带来了巨大的挑战;为了实现对光伏充电站更加有效的管理,在分析分布式光伏充电站数据通信方案的基础上,设计了一种光伏充电站Web实时监控平台;该平台基于ZigBee技术、GPRS-DTU技术、HTTP协议设计了直流充电桩无线传感器数据采集方案,部署数据库服务器、Web服务器以克服充电站无人值守的问题,实现对该分布式系统的集中管控,同时设计用于充电预约、监控、提醒等功能的安卓用户APP以提升用户体验,并对该系统进行实验验证;经验证,该设计方案能够有效实现对分布式光伏充电站的实时数据采集与Web端集中管控,为充电站无人值守与远程监控提供了一种有效的技术解决方案。     

基于B/S架构的嵌入式远程用电管理系统

针对校园中现有用电管理系统的存在的缺陷与弊端,提出了一种基于B/S架构的嵌入式远程用电管理系统的解决方案。系统以ARM-CORTEX-A8为主控板的核心处理器,Linux操作系统为应用程序的运行环境,同时在Linux系统中搭建了嵌入式BOA服务器。系统中使用html语言完成系统与用户的交互页面,并通过CGI技术实现了浏览器与嵌入式服务器的数据交互。为不改变原有建筑电力布线,系统终端采用zigbee无线网络实现远程的用电监控,从而实现远程用电管理系统。为使系统运行效率高,主进程中使用多线程技术完成系统中各任务,系统中使用数据共享内存的方式完成各进程间的数据通信,使用消息队列实现客户端对系统终端设备的控制,系统中通过sqlite3数据库完成所有历史数据的记载。通过系统实验测试,该系统可以正确响应用户需求以及满足校园内所设置的合理用电申请的远程用电管理要求,在安全、节约用电的同时有最大程度的方便了校园内非常规工作需求。     

基于LabVIEW和Arduino的远程监控系统设计与实现

针对现场采集数据实时远程监控的要求,根据LabVIEW强大的功能模块和Arduino灵活易用的开发特点,提出以Arduino为控制器,采用Arduino软件与LabVIEW软件交互编程的设计思想。为解决LabVIEW在本地服务器Web发布的局限性,同时简化系统的硬件设计,增加使用的灵活性,使用云计算作为服务器,设计实现了一种基于LabVIEW和Arduino的无线串口采控和实时同步Web发布的系统。测试结果表明,该系统界面友好,运行可靠,可扩展性很强,可以在整个互联网上通过网页建立Web请求。     

基于Android的综合航电数据监控平台的研制

为实现对某型综合航电系统进行地面在线监控,研制了一款基于嵌入式的数据监控平台.本平台采用Arm处理器,通过以太数据方式,采集航电系统中一系列飞行参数,按照算法进行分析和处理,最终实现了对综合航电系统的工作状态监控.在硬件设计基础上,开发了Android系统下的测试设备驱动及相应应用程序.从工程应用结果表明,该平台能够实现综合航电系统状态的定期检测以及组件故障判断.     

大区域森林中病虫害的视觉监控系统设计与实现

当前的虫害监控主要采用人工经验或翻阅相关资料等的专家分析方法,存在劳动强度大、非实时性和效率低等缺陷;设计并实现了一种基于WEB技术的可判断虫害程度森林视觉监控系统,给出了监控Web服务器、 CC2430 处理器模块、数据采集模块、通信接口和数据库的硬件设计原理,介绍了系统的软件功能以及实现步骤;将软件设计划分成服务器软件和客户端软件两种模块,采用视觉定位方法得到森林虫害区域的空间位置参数,获取深林虫害区域在标准坐标域中的坐标,实现对森林虫害程度的准确监控和判断;系统测试结果说明,该种系统能够对森林虫害程度进行准确的定位和判断,并且具有较高的准确度和效率。     

基于DHCP网络协议的人流密度Web监控系统设计

为了降低踩踏事件发生频率,设计并实现了基于DHCP 网络协议的人流密度Web监控系统,该系统通过DHCP网络协议将现场的人员图像实时传输给服务器,塑造了认证服务器和检测服务器,采用面向服务的架构以及依据角色访问控制相融合的技术管理监控人员的权限,监控人员依据不同的权限进入Web监控平台,Web监控平台实时的通过网络分析、控制、监控终端等模型监控和管理人员流动图像数据,并使用依据人员像素密度阀值的自主报警模块对人流密度进行报警,最终减少了人员踩踏事件的发生;采用该系统对某车站入口处监测点进行应用实验,在Matlab7.0平台上完成测试,实验时Web通信划分成外部干扰能够忽略和外部干扰不可忽略两种情况;仿真时间定为3 000 s,实验结果表明利用文章系统对人流密集区域监控的准确率达到97%左右,误差平均在3%左右,而传统设计误差在20%以上,表明文章系统的鲁棒性更强,更适合推广应用。     

基于Socket通信的工业机器人监控系统研究

针对Epson-G6和Staubli-TX90工业机器人,研究一种基于Socket通信的工业机器人监控系统。系统分为本地监控端和Web远程监控端。基于TCP协议和Socket通信技术,编写了机器人控制器服务端程序和MFC类库开发的客户端程序,客户端分为通讯功能模块,末端坐标轨迹存储模块和基于OpenGL类库的运动姿态展现模块。在此基础上, 基于J2EE架构和WebSocket通信协议编写了Web远程监控端程序,分为用户管理模块和实时监控模块。系统实现了机器人末端坐标轨迹的采集并远程存储至PostgreSQL数据库,同时通过逆运动学计算展现了机器人三维运动姿态,并在Web页面以动态曲线方式监控机器人的末端坐标轨迹。     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

A multi-conjugate adaptive optics （MCAO） can offer a possibility of widening field of view （FOV） characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle＇s expressions of two deformable mirrors （DMs） MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.     

Quick single-photon detector with many avalanche photo diodes working on the time division

Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.