和电路

A dynamic monitoring and identifying system of Fe2O3 series gas sensors for the research of electronic nose is introduced. The system has 6 channels to input 0~2.5V voltage signals, measures system temperature, makes thermoregulation for sensor with hardware and has LCD screen and voice function. The heating circuit using TL494 chip and PWM mode is realized. Offline and online identification is realized. The hardware design is based on 16 bits MSP430F149 microcontroller. The software design for digital acquisition and identification based on Windows operating system is compiled by Visual Basic 6.0. The test results show that friendly interface, simple operation, accurate data, reliability and stability are obtained. The real-time monitoring for all of the sensors in aerometry or identification can be realized by BP ANN.

介绍了一种用于电子鼻研究的Fe2O3系列气敏传感器阵列动态测试、控制和识别系统；该系统能够同时采集6路0~2.5V的模拟电压信号，测量系统温度、硬件对传感器进行温度补偿，同时具有液晶显示和语音功能；加热电路用TL494芯片采用PWM方式实现，能实现脱机和联机两种不同的识别模式；以16位单片机MSP430F149为核心设计了硬件系统，用Visual Basic 6.0设计了基于Windows操作系统下的数据采集与模式识别软件；该软件界面友好，操作简单，数据结果准确，运行可靠、稳定，既可以长时间实时显示各传感器的全部动态响应过程，又可以用BP神经网络进行模式识别。

There are some information about the development of soft switch and welding machine. There are also introduce some methods about the athwart invert current and how to realize it. At last we introduced the structure of DSP and how to design the module by software.

在本论文中首先介绍了软开关技术和电焊机的一些发展，然后介绍了几种典型的逆变电路和实现逆变的方法，最后讲述了DSP的硬件结构和模块以及控制软件的设计方法了软件中的模块。

And from the development of automatic block both at home and abroad, the frequency type automatic block and cab signal seem to be the best.

从满足轨道电路的四条基本要求出发，作者提出使用不同信号周率时的比较标准和计算公式，列出计算结果和曲线，说明频率式自动闭塞和机车信号采用亚音频的周率范围最为合宜。

In the paper,connection of bridge rectifier in rotor,arrangement of winding in the stator and the rotor,analysis of performance of the generator nonloaded and fully-loaded and design characteristic of the generator series are discussed respectively.Some considerable problems in design and m...

着重介绍了该发电机转子旋转整流电路的接线方式和定、转子绕组结构，分析了发电机在空载和负载2种情况下的运行特性以及该系列发电机的设计特点，指出了采用该励磁方式的单相交流同步发电机在设计和制造过程应注意的问题。

This can also be divided into two categories: one is to discuss the influence of power factor by way of dividing power circuit into capacitive and emotional under the circumstance of unchangeable voltage and frequency of output power, and the other is discussed the influence from voltage and frequency of power to power factor with the situation of constant component parameters.

具体又分为两种情况：一种是在电源的输出电压和频率都不变的条件下，把电路分为容性和感性，讨论了元件参数对功率因数的影响，另一种是讨论了在元件参数不变的条件下，电源的频率和电压对功率因数的影响。

Firstly, oscilloscope control system based on GPIB technique is presented with friendly operation environment to the HIFU system, and it uses multithreading technique in programming to realize real-time recording and display of the signal; Secondly, temperature collection and data recording system is designed, which also could get real-time recording and display of the 16 channel temperature signal, and it's believed to be of great use for further experiments of the HIFU system; Thirdly, multiple ultrasonic phased array's phase shifter is designed,which could provide 8-bit phase control in a range of frequency where the centrical frequency is 1MHZ. Fourthly, the module of serial communication is realized to insure the communication between devices and computer, including both synchronous and asynchronous communication, which enables the system to transfer data reliably and stably; Finally, the module of digital quantity control is accomplished, which provide for upper application the consistent solution to the control of exterior devices via digital interface. It can get or set the devices state using interrupt mode to receive input signal or send output signal.

主要有以下几个方面：设计了基于GPIB的示波器控制系统，给课题的研究工作提供了一个良好的环境，它采用了多线程编程的方法，能够较好的实时显示当前波形并记录数据；设计了温度采集和数据记录系统，能够对16路温度信号进行并行同步的实时采集，用于HIFU剂量学研究中温度场检测和医疗评价；设计了相控阵相位延时电路并且通过调试，满足了课题的相位控制的要求，在中心频率为1MHZ左右的频率范围内都能够达到8-bit相位控制；实现了串口通讯模块，为各项设备与计算机之间的通讯提供保证，它提供同步和异步的通讯能力，使系统能够可靠稳定的传输数据；建立了数字量控制模块，为上层应用程序提供一致的方法使用数字接口控制外部仪器，它使用中断的方式来接收输入或输出设定的开关量信号，从而得到或设定各种仪器的状态。

This paper introduces the research results of techniques of testing PC pump oil well through one-year efforts. Which covers the mathematical models of a number of force characteristics strength analysis, and resonance critical problems of rotation rod-string in PC pump wells: resulting of testing method of polish-rod load and rotation rate on the basis of feasible demonstration and technical requirement analysis; study and manufacture of system of testing PC pump well, which involves sensor, collector ring, acquisition circuit and computer; research and determination of assistant technology of testing force on rotation polish-rod and formulation of testing force on polish-rod. A spot testing has been carried out by means of the above research fruit and good results have been achieved.The success testing results in has laid a strong foundation for the oil well diagnosis.

本论文介绍了对螺杆泵采油井的研究成果，其内容包括，对螺杆泵采油井中的旋转杆柱的若干受力特征、强度分析方法及共振临界问题进行数学建模；在可行性论证和技术需求分析的基础上，研究产生了对油井进行光杆负载和旋转速度测试的办法；研究制作了螺杆泵采油井测试系统，它包括传感器、集流环、采集电路和计算机等；研究确定了对实施旋转光杆测力的辅助工艺；制定了对光杆受力进行测试作法，利用以上研究成果实施了现场测试，并取得了理想的结果。

UL60950 requires minimum creepage and clearances distances be maintained between the Tip and Ring traces and all other circuits.

符合UL60950最低要求的爬电距离和间隙之间的小费和环痕迹和所有其他电路维持。

A sidestream CO2 concentration measurement device using infrared method for medical is researched and developed in this paper. The module uses a detecter based on infrared absorption, and obtains gas sample from patient respiratory route through sidestream airway. A microprocessor is used to collect and process data, and to communicate with patient monitor, receiving commands, transmitting wavedata and parameters.

本文研制了一种医用旁流式红外吸收CO2浓度检测装置，利用红外吸收气体检测原理设计CO2浓度探头和信号放大电路，使用旁流式采样气路获取病人呼吸气体的样本，以32位微控制器为核心的信息处理系统负责对信号进行采集、处理，以及与主机通讯接受控制命令和传输波形数据和计算参数。

The change and the distribution of magnetic field in magnetic core are described with system state equations of magnetic switch and Jiles-Atherton model so that whole operation of magnetic switch and its application circuit can be obtained, meanwhile total loss, eddy current loss and magnetic hysteresis loss of magnetic switch can be calculated.

利用磁开关的系统状态方程和Jiles-Atherton磁滞回线模型描述磁芯中磁场的变化和分布，从而得到磁开关及其应用电路的整体工作特性，同时计算出磁开关的总损耗、涡流损耗和磁滞损耗。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。