共查询到20条相似文献，搜索用时 62 毫秒
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传统模拟式温度、湿度传感器通常存在复杂的校准和标定问题。使用DHT11数字型温湿度复合型传感器,设计了一种基于AT89C52单片机温湿度监控和报警系统。系统可以实时将当前环境温湿度数字显示在液晶LCD上,实现温湿度的监控功能,并且可以设定温度和湿度的上下限,当系统检测到当前温湿度超出界限时可以通过蜂鸣器智能报警。研制出来的系统精度高、功耗低、使用方便,可以满足日常生活和工厂环境等的温湿度监控需要。 相似文献
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《实验室研究与探索》2017,(12)
为有效减少道路交通事故发生率,最大限度保护驾驶员和乘客,以Arduino Mega 2560单片机为核心,结合HC-SR04超声波测距模块设计了一种汽车并线辅助系统。该系统在运行过程中模拟真实路况,利用超声波原理,当驾驶员开始拨动转向灯杆准备做并线或者超车的动作时,系统启动检测汽车后视镜盲区及相邻车道后方是否有正在行驶的车辆;当超声波测距模块检测到相邻车道后方有行驶的车辆,并且与该车辆的车距小于设定的安全值时,系统启动报警模块,主动对驾驶员发出危险报警,驾驶员根据报警系统的提示以及后视镜的情况判断是否可以安全并线。该系统具有测量精度高、性价比高、改装方便的优点,对汽车安全驾驶有着良好的辅助作用。 相似文献
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王宁 《赤峰学院学报(自然科学版)》2007,23(4):30-31,33
单片微型计算机控制技术是计算机应用领域中一个重要的组成部分.本文介绍MCS-51单片机应用于船舶监测报警系统,是适应现代船舶管理自动化的要求.重点介绍了该系统的硬件设计、软件设计,突出了该系统的设计特点,即多路报警,声音和闪光报警及自检功能. 相似文献
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火灾自动报警系统是多功能酒店自动消防设施的一个重要组成部分,本文就该系统在设计、使用过程中需注意的问题,如火灾自动报警系统各构件的设计、选择,构件之间联动功能的实现等方面进行探讨。 相似文献
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超声波水位监测仪是基于STC89C52单片机进行设计的.硬件电路部分主要由主控制器模块、超声波发射模块、超声波接收模块、显示模块及报警模块等5个模块构成.软件部分采用单片机C语言程序编程,主要由键盘扫描、定时器/计数器初始化、超声波发射子程序、中断服务子程序和LCD动态显示子程序构成.实验证明,该系统能够用于衡水湖水位监测. 相似文献
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依据超声波液位检测原理及方法,设计了以单片机和上位机为核心的多点液位远程监测系统.设计了基于单片机的超声波发射和接收电路,在发射和接收电路上均采用程控增益放大,利用新型STC单片机的捕捉功能提高时间测量的精度.上位机软件采用组态王6.51开发,实现了罐区内各油罐液位的集中显示和存储. 相似文献
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房颖 《河北软件职业技术学院学报》2010,12(1):50-54
设计并实现了一种基于PIC单片机、以太网通信技术的智能家居安防监控报警系统,给出了系统的功能和结构以及硬件原理框图和软件设计思路。该系统主要采用Mi-crochip 16位单片机与以太网控制器ENC28J60芯片组成的硬件电路。经过调试与检测证明,该系统性能可靠,易于使用,不仅有效地实现了快速报警、远程监控功能,还提高了家庭安防报警的可靠性,具有广泛的实用价值。 相似文献
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根据现场总线系统的结构和技术特点,论述了在船舶机舱监测报警系统中采用现场总线技术的优越性,探讨了利用CAN总线的可行性,提出了基于CAN总线的船舶机舱监测报警模拟系统构造方案,并对该监测报警系统的组成、功能等进行了论述。 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献