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- 离心机毕业设计
2013-07-03 12:22:04
598
1
- 毕业设计数字频率计设计
2012-11-27 14:46:56
466
1
- 机械类毕业设计题目
- 求偏向于机械设计方面的毕业设计题目~
2018-01-14 21:19:23
282
1
- 函数信号发生器毕业设计
2018-12-01 10:12:31
306
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- 音频信号发生器毕业设计
- 1.频率范围(带宽):200HZ~20KHZ2.输出电压(连续可调)3.非线性失真(在频率范围内)4.负载电阻为30我不知道从何下手.................. 1.频率范围(带宽):200HZ~20KHZ 2.输出电压 (连续可调) 3.非线性失真(在频率范围内) 4.负载电阻 为30 我不知道从何下手............... 展开
2010-03-13 14:25:28
399
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- 半导体激光器可以做什么毕业设计
2016-10-15 17:23:04
316
3
- 数字式频率计的毕业设计
- 我要做的是数字式频率计的毕业设计(用CPLD),谁有相关论文,给我介绍介绍啊,要是有以前的论文,给我点啊,我都不明白CPLD,还需要VHDL语言编程,我更是不会了
2008-03-05 20:39:05
399
1
- Dcs与组态软件毕业设计
- 求毕业论文,利用组态软件和集散系统实现工厂电能使用量的监测,报警显示,趋势曲线。具体怎么设计的那种可以发我邮箱axy1211@126.com... 求毕业论文,利用组态软件和集散系统实现工厂电能使用量的监测,报警显示,趋势曲线。 具体怎么设计的那种 可以发我邮箱axy1211@126.com 展开
2009-04-27 13:35:29
467
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- 求函数信号发生器毕业设计
- 设计要求:1.正弦波、三角波、方波输出频率范围:1kHz~10MHz;2.具有频率设置功能,频率步进:100Hz;3.输出信号频率稳定度:优于10-4;4.输出电压幅度:在负载电阻上的电压峰-峰值V... 设计要求:1.正弦波、三角波、方波输出频率范围:1kHz~10MHz; 2.具有频率设置功能,频率步进:100Hz; 3.输出信号频率稳定度:优于10-4; 4.输出电压幅度:在 负载电阻上的电压峰-峰值Vopp≥1V; 5.失真度:用示波器观察时无明显失真。 展开
2008-11-25 12:26:58
331
1
- 毕业设计: 车流量监测 红外技术
- 这个要做实物 ,不用很复杂,简单点就行希望可以有个电路图 和程序
2018-03-06 10:39:34
407
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- 发酵罐的PLC控制(毕业设计)
- 毕业设计,题目为“发酵罐的PLC控制系统设计”。急求相关方面的资料。 及综述论文的写法,Z好推荐一篇范文。谢 资料资料!
2010-03-15 23:35:58
384
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- 超声波传感器可以用作哪些毕业设计
2015-09-08 14:14:37
386
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- ZEMAX,小白求助做毕业设计。
- 这张2Dlayout的图,我想知道蓝色绿色红色各表示是什么意义,然后第12光阑面实际作用是什么?
2015-05-11 00:17:44
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- 电气毕业设计选什么好
2017-01-19 07:43:39
390
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- 手机射频方面的毕业设计
- 求一个手机射频方面的毕业设计的题目
2010-03-26 09:56:07
351
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- 有没有能做plc毕业设计仿真的
2018-11-13 08:05:53
236
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- 倒车测距仪毕业设计参考什么书籍
2018-11-21 08:19:06
273
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- 哪有计算机嵌入式 linux毕业设计论文范文?
2013-12-21 06:01:48
341
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- 基于AT89C51单片机的数字频率计毕业设计
- AT89C51单片机 测频范围10HZ-10MHZ 多种波形 ZD是需要添加其他功能 比如测幅值 之类的 (添加功能任意 保证毕业设计的工作量不会太简单) 不支持私下交易,求淘宝链接之类的
2015-11-09 03:36:40
514
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- 毕业设计外文翻译,高手请进,感激不尽!
- ResearchonIntegrationofCoalMineMonitoringandControlSystemwithFieldBusControlSystemAbstract:AccordingtotheconstructionofcurrentcoalminemonitoringandcontrolsystemsinChina,t... Research on Integration of Coal Mine Monitoring and Control System with Field Bus Control System Abstract:According to the construction of current coal mine monitoring and control systems in China,the paper proposes three kinds of applicable schemes of integrating PLC and DCS systems with field bus technology to digitize the system and to improve the flexibility and extent of the system.Essentially,the paper introduces the integration of FCS on I/O layers.Based on a real coal mine safety-monitoring and control system applied with a CAN field bus,the major technology of system relays and extensions is discussed.We believe that one of the most applicable methods is currently replacing the connection between function-stations and field-sensors with a CAN bus on I/O layers for system integration. Key words:monitor and control;field bus control system;CAN;integration 1 Coal Mine Monitoring and Control System and Field Bus Technology As one of the most important methods to improve modern management and production efficiency in coal mines,monitoring and control technology have been widely adopted to maintain safety in coal production.Taking advantage of foreign technologies from the 1980’s,coal mine monitoring and control systems have expanded rapidly in China.At present, automatic control has come into use in most large-scale coal mines,which greatly improved production efficiency and safety and lowered costs. In China,most sub-systems of coal mine systems work independently.They follow a DCS system structure of three layers(center layer,sub-station layer and sensor layer)which consists of a tree to-pology.They are composed of sensors,sub-stations on or under the ground,center stations,multiple controllers and display terminals(Fig.1).They work with analogue signals of 4–20 mA or 200–1000 Hz. Each coupled cable can only act as one line for transmission[1]. Currently control networks have been developed for digitalization and networking.Because traditional analogue signals of 4–20 mA or 200–1000 Hz can only carry simple measurement information and con-trol signals,the communication rate is restricted. Therefore,it is necessary to digitalize and network the entire monitoring and control system. Fig.1 Traditional Structure of Coal Mine Monitoring and Control System 展开
2018-11-22 17:28:40
465
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