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为了满足汽车道路疲劳试验的数据远程采集与实时监控的要求,开发了基于WinCE系统和GPRS通讯网络的远程车载数据采集监控系统。车载终端采用嵌入式PC作为核心,利用外围电路接口连接A\D模块、CAN总线模块及GPS\GPRS模块;在WinCE系统上开发软件,协调车载终端内部各个模块工作、运算、及数据处理与存储,通过GPRS通讯模块将关键数据发送到监控中心,实现了汽车道路疲劳试验的远程数据采集与监控。 相似文献
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基于无线传感器网络的农田灌溉远程监控系统 总被引:2,自引:0,他引:2
为了实现自动灌溉控制,节约农田灌溉用水,设计了一套集农田土壤温湿度监测、泵和电磁阀控制、远程管理的灌溉远程监控系统.该系统以433 MHz频率为核心开发无线传感器网络节点,完成农田土壤温湿度实时监测.基于ARM9微处理器S3C2410构建基站,对比已存储在数据库中的限值,由基站控制泵和电磁阀的启闭,并通过GPRS无线传输方式进行灌溉系统的远程实时监控,远程监控中心采用Citect组态软件实现数据、人机界面管理.试验中,选用4组无线传感器网络节点,分别测得25 cm深度土壤的温度和湿度,数据采样时间间隔为30 min,基站根据土壤信息控制泵与阀门的开闭,并通过GPRS无线网络传输至远程监控中心.试验表明系统使用灵活、功耗低、人机界面友好,能较好地满足农田灌溉远程监控的应用需求. 相似文献
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针对目前雪野水库闸门控制仍然采用现场人工操作的问题,提出了一种基于GPRS和PLC的闸门远程监控系统设计方案。首先概述了系统中应用到的一些先进技术,然后介绍了系统的总体结构及工作原理。该系统采用GPRS技术实现了现地控制层设备与中央控制层设备之间的无线网络连接,为水库闸门的远程监控提供了一种新的技术手段。 相似文献
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该文介绍了基于GPRS网络的电力负荷远程智能监控系统。该系统利用GPRS的无线通信及Internet接入功能,实现了分散电力大用户的数据实时采集、传输、存储、事件报警以及WEB发布等功能,并集管理、负荷监控、远程抄表和防窃电于一体,可满足现代电力管理的要求。还详细论述了系统的主要功能、结构原理以及软硬的实现,给出了系统框图以及软件流程。 相似文献
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针对目前雪野水库闸门控制仍然采用现场人工操作的问题,提出了一种基于GPRS和PLC的闸门远程监控系统设计方案。首先概述了系统中应用到的一些先进技术;然后介绍了系统的总体结构及工作原理。该系统采用GPRS技术实现了现地控制层设备与中央控制层设备之间的无线网络连接,为水库闸门的远程监控提供了一种新的技术手段。 相似文献
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工程机械远程监控系统的实现 总被引:1,自引:0,他引:1
移动通信与监控技术的结合,可以将用户的监控数据以便捷的方式传送至目的地而几乎不必考虑实际距离的限制,因此在施工分散的工程机械中得到了广泛的应用。它把移动通信中的GPRS应用于沥青洒布车工作状态的远程监控,重点介绍了该系统的总体结构和设计方案。 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献