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1.
针对儿童被诱拐、大学生被拐骗、老年人走失、成人与幼儿溺水等各种突发紧急事件及不法侵害的出现,本系统设计基于Android平台的GPS定位报警系统.在移动端系统使用GPS模块进行定位,将GPS模块采集到的地理位置信息通过GSM网络上传到云服务器,并开发An-droid客户端的程序对云服务器转发的用户位置信息进行接收,再将接收到的数据在地图上进行匹配.同时,当移动端用户发出报警信息时客户端用户可以接收短信并展开定位追踪.本项目设计的个人定位报警系统既具有定位功能,又能实现应急情况实时报警功能,可以有效地保证人身财产安全.  相似文献   

2.
该研究设计的GPS定位信息显示系统使用LabVIEW软件采集GPS模块输出的定位信息。GPS接收模块与计算机的串口相连,LabVIEW程序从计算机串口读取GPS定位信息并实时、准确的显示出来。  相似文献   

3.
为了保障舰船在海上能够快速有效的定位,并且实现全球定位功能,本文介绍了一项利用单片机采集和处理GPS定位信息的设计。该系统以ATMEL公司的AT89C51单片机为核心控制器件,通过串行口与GPS模块HOLUXGR87通信,接收GPS模块输出的时间和定位信息,该输出信息格式采用NMEA-0183标准格式中的GPRCM语句。单片机接收到定位信息和时间信息后,将GPS模块输出的时间信息进行时差调整,再将所获取的位置和时间信息通过显示终端显示。经过调试后,本系统可以接收GPS定位信息和时间信息,并把经度、纬度和时间通过屏幕显示出来。  相似文献   

4.
随着GIS技术的发展和应用,视频多媒体信息在GIS系统中的应用也越来越广泛,提出在嵌入式系统下,基于达芬奇技术,将视频信息与GPS定位信息相融合形成可定位视频的方法。通过在视频帧分包处理中加入GPS定位信息分包,将视频和GPS定位信息有机融合,并通过线性内插的方法解决在采集过程中GPS信息接收频率与视频采集频率不一致的问题,最后在达芬奇技术平台TMS320DM3730上实现可定位视频的采集和传输。  相似文献   

5.
针对汽车防盗及定位需求的日益增长,基于单片机微处理器、GPS、GPRS等技术,采用模块化的设计方案设计了汽车防盗报警系统,实现了实时定位、短信报警的功能,即系统采集到车辆被盗信息后,启动GPS定位模块,接收车辆位置信息(纬度、经度等),单片机对该定位数据分析与处理后,通过GPRS网络以短信形式发送至车主手机。通过软硬件调试,系统运行数据显示,该系统实时性强、准确性高,车辆报警响应时间为秒级延时,定位误差在经纬度0.6度以内。  相似文献   

6.
基于National Instructionals公司的LabVIEW虚拟仪器技术,设计和搭建了车辆监测系统。利用车载GPS/北斗定位接收系统获取定位信息,通过GPRS将定位信息传递至监控台,监控台将信息汇总后返回至每一车辆,将所有车辆的位置信息共享并显示。监测及显示软件通过LabVIEW编写,以期实现车辆运行状况的实时监控。实验结果表明,该系统能够精确有效地监测和显示车辆的运行状况。  相似文献   

7.
主要研究了雷达监控系统通过接收GPS卫星定位信号,获得高精度的时间信息输出,用于整机雷达的时间授时及位置信息锁定的技术,对GPS的数据采集系统进行了深入分析,并重点介绍了该系统的硬件设计及应用程序设计等。上位机监控系统能够实时显示更新经纬度信息,并存储历史数据。研究结果表明,该系统稳定可靠,可以广泛应用于常规地面雷达产品及其它自动控制产品领域中。  相似文献   

8.
GPS具有全天候作业、定位精度高、观测时间短、操作简便等特点,但是其价格昂贵,很难应用在大坝等实际工程中。GPS多天线系统是将微波技术、计算机实时控制技术、大地测量数据处理和定位算法有机的结合起来,仅用一部GPS接收机互不干扰的接收到8个GPS天线传输来的信号,并通过后处理实现精密定位。浦东海塘GPS位移监测系统,实现了海堤自动化的实时位移监测,而且采用GPS一机多天线监测系统,大大降低了监测系统的成本。本文通过对海堤上的实验结果及分析,表明该监测系统成本低、精度高、可靠性高,具有很广的应用前景。  相似文献   

9.
基于GPS一机多天线的大坝形变监测系统   总被引:5,自引:0,他引:5  
何秀凤  王新洲等 《导航》2002,38(3):30-35
GPS多天线系统是将微波技术,计算机实时控制技术,大地测量数据处理和定位算法有机的结合起来,仅用一部GPS接收机互不干扰的接收到8个GPS天线传输来的信号,并通过后处理软件包实现2-3mm定位精度,本文介绍了作者开发的GPS一机多天线控制系统在大坝形变监测中的应用。  相似文献   

10.
主要阐述在Windows操作系统下结合GPS技术和电子地图技术,将用户当前的地理位置在电子地图上准确地表示出来的一种实时GPS定位技术。从开发一个小型GPS/GIS系统所必须涉及到的几个方面入手,遵循从GPS信号的接收、处理开始,到电子地图的开发制作,最后到GPS定位功能的实现的步骤,其思路清晰、浅显易懂,对于初学者和开发复杂的GPS/GIS系统有很好的参考价值。实验表明,以此种方法设计的小型GPS定位系统,精度较高,可以满足一般的民用定位要求。  相似文献   

11.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

12.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

13.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

14.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

15.
The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO>6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.  相似文献   

16.
Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.  相似文献   

17.
We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.  相似文献   

18.
Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources' evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping (266 nm) at power densities of 25-153 kW/cm^2. The full width half maximum (FWHM) of the lasing mode is 0.67 nm  相似文献   

19.
By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.  相似文献   

20.
正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-  相似文献   

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