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1.
许辉  倪长宝  曹新 《电子设计工程》2012,20(13):172-175,178
针对传统人工采集费时费力和有线监控布线复杂、维护困难的局限性,将传感器与ZigBee无线网络技术相结合,提出了无线传感网络的智能机房环境监控系统的设计方案,并进行了实现。该系统利用ZigBee技术实现对采集数据及信息的无线收发,通过公共网关接口CGI将数据和控制信息传送到互联网,操作人员从远距离的PC机上实时查看数据、实施控制,从而实现了真正意义的远程监控。  相似文献   

2.
魏永帅  鲍可进 《数据通信》2014,(3):13-17,35
设计了以OMAP3530为核心的嵌入式平台并采用Android系统的家庭网关,搭建ZigBee无线传感网络实现家居有关信息的采集并传输到家庭网关,远程手机终端可通过3G网络与家庭网关建立连接,实现了家居环境的本地、远程移动监控和短信报警功能.开发的基于Android操作系统的家庭网关和远程手机终端软件UI界面友好,易于移植和使用.此外,对ZigBee网络通信数据进行AES加密,以保障数据的私密性和家庭无线传感网络的安全性和稳定性.结果表明:该系统采集数据精度较高且性能稳定,有良好的安全性和扩展性,具有很强的推广应用价值.  相似文献   

3.
如果需要对条件比较恶劣的工作环境进行监测,ZigBee无线传感网络是非常合适的选择。基于ZigBee的无线传感网络能够利用无线传感器、协调器和监控中心等形成一个无线网络,该网络的监控节点主要通过无线传感器获取监控信息,然后通过协调器和监控中心的嵌入式网关连接起来。这是一种基于簇的分层结构,其具有分布式处理能力,能将获取的信息经过簇头的融合后,通过RS 232接口直接将数据传送给监控中心。  相似文献   

4.
为了实现对ZigBee网络远程监控,讨论了在ZigBee网络中采集的物品信息如何用GPRS接入Internet的方式,从而实现远程对ZigBee无线局域网络的信息监测与控制。  相似文献   

5.
物联网网关作为连接传感网与传统通信网络的纽带,在即将到来的物联网时代将发挥重要的作用。文章设计了一种基于嵌入式系统的物联网网关,针对ZigBee无线传感网通信距离短、通信速率低的困扰,将ZigBee通信协议与以太网、GPRS等通信协议进行转换,实现对ZigBee节点的远程监控。系统以ARM9系列的S3C2440为主控芯片,采用模块化的设计思路,围绕主控制器搭建了相应的外围功能模块。软件方面,移植了Linux嵌入式操作系统,在网关节点上搭建web服务器,编写了相应的应用程序来实现物联网网关的功能。经测试,该网关功能稳定可靠,实现了无线传感网与传统通信网络之间的数据通信。  相似文献   

6.
基于ZigBee和WLAN的智能家居监控系统的设计   总被引:4,自引:0,他引:4  
综合zigBee无线传感器网络和无线局域网(WLAN),设计了集多传感、分布式处理和事件触发监视于一体的具有双层网络结构的智能家居多媒体监控系统.ZigBee网络由标量传感节点和多媒体传感节点(网关)基于IEEE 802.15.4/ZigBee协议构建.负责采集标量数据上传到WLAN或执行来自上层的指令.多媒体传感节点基于WLAN连接到远程监控中心形成远程视频监控网络,将ZigBee网络上汇聚来的传感数据、报警信号和压缩视音频流等多媒体数据发送到监控中心及用户.利用此系统,为用户提供家居环境参数监测、报警、事件触发或持续的远程家居监控功能.  相似文献   

7.
基于ZigBee的温室环境监控系统的设计   总被引:1,自引:0,他引:1  
针对现有温室环境监控系统的安装成本问题,文章提出并实现了基于ZigBee的温室环境监控系统。该系统由智能感知系统和智能网关两部分构成。智能感知系统由分布在温室内的四个感知节点和一个一体化控制器构成,自组织形成ZigBee无线传感网。智能网关由协调器和嵌入式Web服务器两部分构成。协调器通过ZigBee无线传感网获取四个感知节点的温度、湿度、光照度和气压等数据,并通过串口与嵌入式Web服务器实现数据交互。实现了温度、湿度、光照度和气压等数据的远程Web访问,以及遮阳系统、通风系统和喷淋系统的远程控制。  相似文献   

8.
随着无线网络技术和传感技术的发展,物联网时代促进了无线传感网络监控系统的发展,监控系统已经从视频监控的传统模式被无线传感网络的监控模式所取代.无线传感网络监控系统中最主要的技术是ZigBee技术,ZigBee技术可以实现多个传感器之间的相互通信.本文对无线传感器网络的特点和功能进行了分析,在ZigBee技术的基础之上对无线传感器网络监控系统的硬件和软件进行了设计和研究.  相似文献   

9.
为实现互联网与无线传感网络ZigBee互通,提出了一种基于嵌入式系统网关设计方案。介绍了ZigBee与TCP/IP协议的分层结构及作用,网关硬件以TI AM335X与CC2530F256芯片为核心组成,模块间以串口进行通讯。在网关中TCP/IP与ZigBee协议的解析由各自模块实现,网关通信采用C/S结构,通过串口实现在应用层互联网信息与ZigBee信息交互。该方案具有实现结构简单、对用户透明,但无线传感网络规模受限。  相似文献   

10.
为提高传统仓库管理方法的时效性和测控精度,设计了基于3G-ZigBee技术的远程仓库实时监控系统。ZigBee无线传感网络对仓库内的环境信息进行采集,将数据汇聚至3G-ZigBee网关,网关利用3G网络传送至远端监控中心。该系统不仅能实现多点数据采集和远程数据传输,还能大幅减少工作量,具有较高的时效性和可扩展性。  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

17.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

18.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

19.
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.  相似文献   

20.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

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