基于物联网的小区智能照明管理系统设计与实现

针对国内中小型LED照明企业的艰难处境和政府倡导低碳,绿色环保照明政策现状,提出了一种基于电力载波通信技术的小区智能照明管理系统的设计方案。采用微控制器、PLC芯片和传感器构建智能控制终端,实现对单灯电能、光强度等数据采集。集中器集成GPRS通信模块负责与远程控制中心建立连接,控制终端与集中器通过电力线相连,实现PC端和移动端对LED照明设备的多平台控制。重点阐述了智能控制终端的软硬件设计、系统的自定义通信协议和远程控制方法。系统实测结果表明,该系统数据传输可靠、响应时间短、成本低,易于进行远程管理和控制。     

基于物联网技术的教学楼电器智能监控系统设计

针对校园用电严重浪费问题,为实现校园节能,结合物联网和多种数据传输技术,设计了一种对学校教学楼各教室内电器集中化、网络化和智能化的监控系统。该系统以监控网关为自动控制中心,对ZigBee网络的终端节点采集的每个教室光强、温度、人员活动以及所有教室常用电器开关状态等信息,自动做出智能判断并向ZigBee网络终端下达开关常用电器以及门窗的指令;同时,连接至校园网的监控网关也作为服务器,采用浏览器/服务器和客户端/服务器模式,在Windows客户端、Android手机客户端和Web浏览器实时远程查看每个教室用电器的工作状态,并可以远程人为干预各教室门窗和用电器的开关。该系统不但实现了远程人为控制用电器,而且可根据各教室的光强、温度以及人员活动等情况,自动智能控制每个教室内常用电器及门窗的开关。实际测试表明,该系统具有良好的可靠性和稳定性,大大减少了校园的能源浪费。     

路边停车场管理系统的研究和实现

针对智慧城市建设对智能交通的需要,设计了一种基于物联网技术的智能路边停车场管理系统;该系统采用地磁传感器作为信息采集设备,利用ZigBee和GPRS无线通信技术实现数据的远程传输;应用MySQL数据库、tomcat 6.0服务器搭建后台信息管理服务器,实现对多个路边停车场的统一管理;实地测试表明,系统稳定可靠,检测准确率达到了98%,成功实现了信息的实时及时发布和智能化管理,可以应用于实际的城市路边停车场管理。     

城市LED照明系统远程监控平台设计与开发

针对城市中大规模LED路灯照明系统,设计和开发了一种基于C/S结构的城市LED照明系统远程监控平台;对系统组成结构和工作原理进行了分析,并对软件平台的关键模块、传输协议、数据库服务器及GIS系统进行了研究;提出了一种综合IOCP完成端口、多线程、GIS、数据库以及无线网络通信技术等集成一体的LED照明系统的远程监控平台设计方案,在整体技术上具有一定的集成创新特色;为了解决大量客户端并发访问导致的网络通信问题,将IOCP模型技术和多线程机制应用到通信服务器网络通信模块中;同时,基于MapX在Visual C++平台上进行了地图开发,并利用MYSQL数据库保存和管理运行数据;实验结果表明,该系统具有良好的可靠性与伸缩性。     

基于NI WSN的智能家居监控系统设计

随着物联网和计算机技术的不断发展,智能化、网络化、信息化是现代家居系统的必然发展趋势。将NI无线传感器网络(WSN)技术引入到智能家居监控系统的设计中,基于NI WSN系列产品进行了无线智能家居系统的总体框架、硬件型号和软件流程设计。系统的传感器节点分别采集盗情、烟雾、温湿度等参数,以无线形式通过网关将数据传输至上位机PC,在PC端利用Labview软件实现了智能家居防盗系统、火灾报警系统、环境舒适度等参数的实时在线监控,取得了良好的人机交互界面,并具有远程终端监控功能。该智能家居监控系统具备低功耗、实时性好、易扩展及可现实远程监控等优点,在智能家居领域具有广阔的市场前景和推广应用价值。     

基于KNX的地下停车场智能监控及车位引导系统

针对目前地下停车场的自动化监控和管理方式单一,缺乏智能化的停车位引导以及停车场内照明、通风、泵站设施管理方式落后等问题,提出一种基于KNX的地下停车场智能监控及车位引导系统;通过将各个KNX节点设备挂载到KNX总线上,构建KNX系统,通过挂接在KNX总线上的智能终端实现对整个地下停车场的监控与管理,即实现对停车场照明、通风设备的管理和监控,以及车辆检测、车位检测以及车辆进入车位的智能引导功能;经实践验证,系统运行稳定可靠,实时性好,抗干扰能力强。     

基于即时通讯的电梯远程呼叫系统设计

为实现电梯远程呼叫的应用目标,对即时通讯机制进行了分析,将即时通讯工具引入电气控制领域,提出了基于即时通讯的电梯远程呼叫系统;设计并实现了即时通讯服务器/数据库、电梯终端与用户终端三层架构的通讯系统,给出了三方之间网络通讯实现时的信息交互架构;经过测试,该系统满足一般工程应用的需求,提升了电梯系统的整体运行质量与效率;在即时通讯技术的应用与电梯物联网技术的发展上有一定的参考价值和推广价值。     

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GPRS和ZigBee的节能型LED路灯智能控制系统

针对现有城市路灯控制系统路灯使用寿命短、无法远程操控、不能自动识别故障路灯的问题,提出一种基于GPRS网络技术和ZigBee无线通信技术的节能型LED路灯智能控制系统,使用ZigBee无线网络与LED路灯控制终端通信,并通过GPRS通讯模块接入GPRS网络与远程控制中心相连,实现远程控制LED路灯,此外,通过LED路灯控制终端实时采集路灯电压和电流,实现LED路灯的远程监控。具体阐述了GPRS通讯模块、ZigBee无线网络模块、LED控制终端的硬件设计方案,软件设计流程,系统通信协议和远程控制实现方法。测试结果证明此系统数据传输可靠、响应及时、成本低、易于实现LED路灯的远程控制和远程监控,具有较大的实用性和推广价值。     

实时主动声定位系统设计*

针对在军事演习或爆炸实验中对冲击波超压传感器位置的精确定位,设计了一种实时主动声定位系统。该系统由声信号发射系统、声信号接收处理系统和无线监控终端系统三部分组成。声信号发射系统与无线监控终端以单片机STC12C5A60S2作为核心控制器,接收处理系统以ARM9系列的S3C2440作为核心控制器。发射系统发射四种已知频率的声信号,接收处理系统接收并处理收到的四种声信号,然后把处理结果反馈到无线监控终端。通过实验表明,该系统在一定条件下,能够稳定地发射、接收并处理声信号,达到实时定位目标,并在200 m范围内将定位误差控制在厘米级内。     

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.     

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.     

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.     

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.     

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.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.