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该系统主要由单片机最小系统、红外遥控电路、振动检测电路、控制电路以及报警电路组成。当报警系统启动,有振动时,通过振动传感器接受检测电路发出信号,经过单片微型计算机处理后,输出报警信号,再由报警电路实现报警。报警电路主要由声和光报警两部分组成,在报警电路关闭的情况下,汽车可以发动,在报警电路开启的情况下,汽车是不能发动的。 相似文献
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张晓晖 《信息技术与信息化》2011,(4):68-70,78
本文基于数字电子技术设计出一种数控直流稳压电源.该电源通过拨码开关、按键操作,实现输出电压的预置、递增或递减步进调节,步进电压精度为0.1V,电压调节范围为0-9.9V,通过数码管直观显示输出电压值. 相似文献
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利用光电池的光电转换特性,把光信号的强弱转变成电信号的强弱.根据硅光电池的光照短路电流的特性(即短路电流与光照度成线性关系),把硅光电池接受到的光信号转换成电流信号,再利用电流电压转换电路,把电流信号转换成电压信号输出.电压信号的变化反映出光信号强度的变化,利用这一特性可以实现光强度自动报警控制系统.当电压信号输出到数码显示电路(数字电压表)时,设定适当的参数,可以直接在显示器上显示光强度的大小.当传输给报警电路时,可以制成光强度自动报警控制系统. 相似文献
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针对驾驶员酒后驾车,量刑标准不明确的问题。本文利用MQ-3酒精浓度传感器能很好的解决该问题。MQ-3乙醇气体传感器以驾驶员呼出的气体为采集对象,输出随乙醇浓度变化的电压信号,该电压信号经ADC0832转换,送入STC89C52单片机系统,通过AT24C02与设定的醉酒阈值进行比较,并在LCD1602液晶上显示酒精浓度值,当酒精浓度超过设定值时,通过单片机驱动蜂鸣器进行报警。从而为交警检测驾驶员是否酒后驾车提供了可靠的依据。 相似文献
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该电流检测传感器专门用于检测电源和负载的交直流电流。它直接串联在电路和负载中,一旦负载接入或有微弱电流流过,该传感器就可以提供报警和控制输出,驱动继电器和其它控制电路。它的检测电路与控制输出端绝缘电阻高达109kΩ,隔离电压可以到3×103V以上,空载电流在50μA以下,使用起来非常方便可靠。电流检测传感器可以自动连动其它设备,起到自动检测开关的作用。经过继电器扩流后可以启动或关闭变压器、逆变器、电源等感性、容性及其它负载,其功能与普通负载传感器相似,但成本却很低。工作原理电路原理如图1所示。这里以220V交流供电为例… 相似文献
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对于天然气的研究,各级学者已经进行了很多研究,也得出了不少的研究结果,本文针对这些已经有的研究结果进行了阅读,作者重点对使用气相色谱法来对天然气的成分进行测定进行了研究,从而确定天然气的成分,得到了一个较好的实验数据。 相似文献
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A digital principle is described which permits a linear regulation of gas flow rate. The regulator unit consists of a set of on-off valves connected to parallel flow resistors. The conductivities of the resistors are 1, 2, 4, 8,...,n and combinations of the resisters give the flow rates 1, 2, 3, 4,..., 2n -1. thus a stepwise regulation with a unit step of less then 1 percent of the maximal flow rate can be obtained by a step of 7 values and resisters. By using two ways valus and complementing with a second gas, binary mixtures of controlled composition (molor fraction) are produced. An apparatus is described which utilizes the above principle for mixing oxygen and nitrogen. The flow resisters are made of plastic tubing, and magentic values are used to permit electric control. The limitations of the applicability of tubler resistors due to nonlinear phenomena are discussed. 相似文献
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Sensor nodes in ubiquitous sensor networks require autonomous replacement of deteriorated gas sensors with reserved sensors, which has led us to develop an encapsulation technique to avoid poisoning the reserved sensors and an autonomous activation technique to replace a deteriorated sensor with a reserved sensor. Encapsulations of In2O3 nanoparticles with poly(ethylene‐co‐vinyl alcohol) (EVOH) or polyvinylidene difluoride (PVDF) as gas barrier layers are reported. The EVOH or PVDF films are used for an encapsulation of In2O3 as a sensing material and are effective in blocking In2O3 from contacting formaldehyde (HCHO) gas. The activation process of In2O3 by removing the EVOH through heating is effective. However, the thermal decomposition of the PVDF affects the property of the In2O3 in terms of the gas reactivity. The response of the sensor to HCHO gas after removing the EVOH is 26%, which is not significantly different with the response of 28% in a reference sample that was not treated at all. We believe that the selection of gas barrier materials for the encapsulation and activation of In2O3 should be considered because of the ill effect the byproduct of thermal decomposition has on the sensing materials and other thermal properties of the barrier materials. 相似文献
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分析了气体光谱吸收基本原理,研究了一套光纤传感瓦斯系统,应用于某超化煤矿试验,并取得良好效果.指出基于光谱吸收的煤矿瓦斯光纤传感器,可用于对煤矿瓦斯气体进行大范围监测,也可在线连续监测井下瓦斯气体,其具有广阔的应用前景. 相似文献
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Information not available?Mainuddin M. T.?Beg Information not available?Moinuddin R. K.?Tyagi R.?Rajesh G.?Singhal A. L.?Dawar
The composition of various gas effluents and their flow parameters viz. flow rate, pressure and Mach number are very crucial in determining the output of high power infrared gas lasers. PC based real time gas Flow Control and Analysis (FCA) System which is the heart of the high power infrared gas lasers such as CO2 Gas Dynamic Laser (10.6μm), Hydrogen Fluoride-Deuterium Fluoride (2.7–3.4μm) and Chemical Oxygen Iodine Laser (1.315μm) has been developed and successfully tested for its applications in Chemical Oxygen Iodine Laser (COIL). The system has been realized using the state of the art PCI bus based high-speed data processing electronics, a personal computer and electro-pneumatic components. The system has demonstrated its capability of controlling the flow rates in the range of 1-6500 lpm (in case of nitrogen) with a response time of 50 msec which is mainly limited by the response of the electro-pneumatic valves and pressure reducers used in the present system. The developed system also has the potential to monitor, estimate and display various flow parameters at critical locations of the laser system. More than 600 successful power runs of the COIL have been given using the developed FCA system. 相似文献
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逐线积分气体吸收模型及其在FTIR气体检测中的应用 总被引:1,自引:0,他引:1
介绍了一种精确的逐线积分痕量气体吸收模型,该模型适用于中红外波段大气环境中痕量气体和污染气体检测的理论研究和工程应用。该模型利用HITRAN光谱数据库,考虑了展宽、线翼截断、温度修正及光谱分辨率变化等情况,可以有效地模拟大气环境中多种气体的红外吸收特征。文中详细描述了模型的算法细节,并给出了模型计算的结果与傅里叶变换光谱仪(FTIR)实测数据的对比,还举例介绍了吸收模型在FTIR气体探测技术中的实际应用,并使用该模型对测量的红外傅里叶变换光谱进行了定量分析,模拟了计算校准谱,并与实测光谱进行了非线性最小二乘拟合,实现了在无需测量校准气体的情况下同时对多种气体进行浓度的反演。 相似文献
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