定时

By studying the internal structure and working principle of 555 timer, this paper introduces three typical circuits----Schmitt trigger, Bistable multivibrator and Astable multivibrator----which are composed by 555 timer. Furthermore, it explores the various applications of 555 timer in circuit designing through the expansion of the circuits and eventually same experience and methods offers in circuit designing by using 555 timer.

本文通过研究555定时器的内部结构和工作原理，介绍了其组成的施密特触发器，单稳态触发器和多谐振荡器等三个典型电路，并通过这些电路的扩展，探讨了555定时器在电路设计中的各种应用，由此得出用555定时器设计电路的经验和方法。

The timing gear of chain cover, as its name implies, encloses and protects the timing gears or timing chain and sprockets from foreign materials.

定时齿轮的链条，正如其名字意味着盖住并保护定时齿轮或定时链轮链与国外的材料。

Normally, time measure is including time discrimination and time to digital converter.

本文的第二章介绍了前沿定时、过零定时、恒比定时和ARC定时的特点。

First, mathematical foundation of synchronization, i.e. the theory of parameter estimation is introduced. Then, DA/DD or NDA timing synchronization methods based on the ML estimation of timing parameter are presented. They are all widely applied in actual digital communication systems. Interpolation theory in digital signal processing has application in timing synchronization, which makes the sampling clock independent of the timing control so that timing adjustment is realized completely through digital disposal. The issue of interpolation in timing synchronization is discussed.

首先，介绍了定时同步实现的数学基础，即信号参数估计理论；从定时参数的最大似然估计出发，介绍了基于数据辅助的定时同步方法和基于非数据辅助的定时同步方法，他们在实际的数字通信系统中均有广泛应用；论文探讨了数字信号处理中插值理论在定时同步中的应用，它使得接收端的采样时钟独立于定时控制，定时调整完全通过数字处理方法得以实现。

The working principle and the functions of the monostability multivibrator composed of 555 timer are introduced in the paper,and the time switches are designed.

介绍了用555定时器构成的单稳态触发器的工作原理，对其功能作了进一步探讨，在此基础上设计了一种具有实用价值的定时-非定时两用开关。

For example,speaking 555 timer flakes and intergrated operate amplifier CA3140 to control,it is a normal thing that the timer is coming out,But today this timer adopt 555 timer oscillatory circuit as at time base signal pulse input,choise magnificated intergrated flake CA3140 to manger ,make the timing of 555 steady state time lagmay be increase one hundred multiple.

由于集成块集成度高，功能强，功耗低，速度快，价格便宜，实用灵活，开发周期短等优点，从上个世纪开始，随着各种各样的集成芯片的问世，比如说555定时器芯片和CA3140集成运算放大器芯片，定时器的形成已经是很普通的事情，但今天这个定时器采用555定时器振荡电路作为时基信号脉冲输入，选择可放大的集成运算放大器3140控制器，使555的稳态延时范围可以增加100倍。

I just write out, it can be a regular seconds to complete the function, and the use of timers to complete, regular high accurac...

这个东东是我刚写出来的，这可以完成定时1秒的功能，并且使用定时器来完成，定时精度高，可靠性高。

I just write out, it can be a regular seconds to complete the function, and the use of timers to complete, regular high accuracy and high reliability.

这个东东是我刚写出来的，这可以完成定时1秒的功能，并且使用定时器来完成，定时精度高，可靠性高。

Button D is the power and timing key : When plug in the power, the green light on and the machine will be in standby mode, press one time is on and default timing as an hour, and press twice up to two hours, the third time is three hours, followed by cycle, If you want to turn it off,just long press it and last for 2 seconds,the machine is shut down and the returned to the standby mode,if you want to stop here just power take off.

此键为开机和定时键：插上电源按键底有绿色灯光，此时为待机状态，按一次此键为开机，主机默认定时1小时，再第二次定时2小时，按第三次定时3小时，依次循环，长按2秒为关机，整机又返回待机状态。

Specialized introduction: This specialized raise has the electronic technology and the information system elementary knowledge, can be engaged in each kind of electronic installation and the information system research, the design, the manufacture, the application and the development higher project technology talented person Main curriculum: The signal and the system, the digital signal processing, the correspondence principle, the microcomputer principle and the connection technology, the monolithic integrated circuit principle and the application technology, the DSP technology and the application, the EDA technology, the construction of data, embedded Linux using the programming, the feeling measure technical, the electric circuit theory series curriculum, the computer technology series curriculum and so on individual hobby * software and hardware research and development computer correspondence literature ping pong photography The experience and the personal experience * 2006.6.29-7.8 compile the staff management system management system using the C language, its basic service activity includes: The staff information warehousing, the revision, the inquiry, the insertion, deletes the staff information and so on * 2006.7.10-7.20 monolithic integrated circuit curriculum design period completes the stopwatch the design, namely the initialization timer is 99:99, 0 starts using the monolithic integrated circuit timer fixed time, fixed time arrives when 0s to transmit the signal to cause the buzzer bell, and may realize suspends, the continuation and the replacement function * 2007.7.2- 7.8 practises in Luoyang Big dragon Peony Communication facility Limited company, does has liquid crystal display monitor telephone one, simultaneously visited has served under somebody's banner the correspondence company, and studied has simulated the telephone the design electric circuit, had understood its basic principle * 2007.7.4- 7.18 completed the DSP curriculum in the school to design, realizes the FIR numeral filter, namely transmitted 25 from DSPThe height level, after advocates AC01 D/A to transform the simulation square-wave, then passes to again from AC01 carries on A/D to transform, produces the data signal, after the DSP numeral filter, finally produces the sine wave * 2008.8.1-8.15 to practise in the Zhejiang Jiang hua abundant power tool limited company, studies the computer software and hardware maintenance.

专业介绍：本专业培养具备电子技术和信息系统的基础知识，能从事各类电子设备和信息系统的研究、设计、制造、应用和开发的高等工程技术人才主要课程：信号与系统、数字信号处理、通信原理、微机原理与接口技术、单片机原理与应用技术、DSP技术及应用、EDA技术、数据结构、嵌入式Linux应用编程、感测技术、电路理论系列课程、计算机技术系列课程等个人爱好＊软硬件研发计算机通信文学乒乓球摄影实践经验及个人经历＊ 2006.6.29-7.8 利用C语言编写员工管理系统，其基本业务活动包括：员工信息入库，修改、查询、插入、删除员工信息等＊ 2006.7.10-7.20 单片机课程设计期间完成秒表的设计，即初始化定时器为99：99，利用单片机定时器0开始定时，定时到0s时发送信号使蜂鸣器响铃，并可实现暂停、继续和复位功能＊ 2007.7.2- 7.8 在洛阳巨龙牡丹通信设备有限公司实习，做有液晶显示屏电话机一部，同时参观了旗下通信公司，并学习了模拟电话的设计电路，懂得了其基本原理＊ 2007.7.4- 7.18 在校完成DSP课程设计，实现FIR数字滤波，即从DSP发送25个高低电平，经主AC01 D/A 转换成模拟方波，然后再传给从AC01进行A/D转换，生成数据信号，经DSP数字滤波，最后生成正弦波＊ 2008.8.1-8.15 在浙江华丰电动工具有限公司实习，学习电脑软硬件维护。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐