自动化外文翻译
电气工程与自动化学院
本科毕业设计专业翻译资料（中文读书报告）
学生姓名：王超杰
专业班级：自动化12-06班
学号：311208002219
2016 年 6 月11 日
原文：
Design of Combustible Gas Detection system using Wireless
Transmission Technology
Shijiazhuang Universities of Economics, Hebei, China
zkzhlp@https://www.360docs.net/doc/2012150029.html,
Keywords:TGS813, AT89S52, DS18B20, nRF905, TC35i
Abstract.The detection device of combustible gas are designed in the presented work,using wireless transceiver and GSM network.The system realize the wireless transmission of the gas concentration,and also can send alarm information to user’s mobile when an exception occurs.
The system consists of two parts: a master and slave. The function of the slave is to collect data, process data and transffer the data to the master.The taskof the master is to receive data and display it by LED.
The signal acquisition is completed by sensor TGS813 and A/D converter TLC2543. The wireless transmission is achieved through wireless transceiver nRF905. Since the accuracy of the sensor is affected by the environment,using DS18B20 to achieve temperature compensation.
And with wireless communication module TC35i and GSM network platform, we can send the alarm information to user’s mobile promptly.
Introduction
Gas detection is widely used in petroleum, chemical, metallurgy, family, shopping malls,
gas stations and other places. Currently, how to monitor the hazardous gas fast and accurately
are the important issues. Although the gas detection technology is relatively mature, but most products has many shortcomings, such as single function, operating complex, bulky, expensive
and low sensitivity. Wireless communication technology applied to the gas monitoring field, can resolve the problem of remote monitoring in special environment, such as high temperature, low temperature, toxic gas.and unable to wiring .
In the presented work, the combustible gas detectoris fully functional (with wireless transceiver), simple, small size, low cost, and has high sensitivity. The equipment can greatly improve the system's detection capability and accuracy with temperature compensation algorithm, and also can send alarm information to the user's mobile phone promptly through the
GSM network.
System design
The system consists of two parts as shown in Figure 1.
Fig. 1 Overall system block diagram
The slave part mainly complete data collection and wireless transmission. The master part mainly complete receiving data, displaying and sending alarm message.
The signal of gas concentration is collected by combustible gas sensor which generates a weak electrical signal. The signal can be amplified and stabilized by conditioning circuit. And then A/D circuit converts the analog signal to digital signal which microcontroller can process. In order to improve the measurement accuracy, and reduce the impact of temperature, design a temperature compensation circuit to collect tempreture data. AT89S52 process the collected data and send data to the master by wireless transceiver.
The master receives the data and displays it by LED. And if the gas concentration being abnormal,the system will drive speaker for an alarm signal and use TC35i module to send alarm information to user’s mobile.
Hardware design
Signal acquisition and conditioning circuit. Figure 2 shows data acquisition circuit. TGS813 is a Gas sensing resistive sensor. The conductivity of TGS813 is influenced by the concentration of combustible gases in air, the greater the concentration, the higher conductivity. In system R0, R9, R10 and RS (in
TGS813) form a bridge circuit to convert resistance to voltage signal. Operational amplifier A connected as a voltage follower with resistors R7 and regulator D1 make up the voltage regulator circuit to supply power for the bridge. In order to the voltage adapt to the A/D converter, the voltage is amplified by opamp B, and the magnification can be adjusted through resistor R11.
Fig. 2 Gas concentration signal acquisition circuit
Fig. 3 Temperature compensation circuit
Temperature compensation circuit. The resistance of Rs is greatly affected by temperature. In order to improve system accuracy, the results must be temperature compensated or temperature correction.In system, using temperature sensor DS1820 to collect temperature signal, and using software method for temperature correction.
Wireless transmission module. Wireless transceiver is achieved by a single-chip RF transceiver nRF905. MCU and nRF905 realize data and commands interaction through the SPI interface.The typical applica tion schematic is shown in Figure 4. The antenna part is 50Ω single-ended antenna.The communication frequency is 433MHz, and operating voltage is
3.3V. The value of resistors,capacitors and inductor is determined by the datasheet of nRF905. GSM short message unit. The interface circuit of TC35i and MCU is shown in Figure 5. The communication between MCU and TC35i is via serial, and the rate is 9600bps. Communicationsmode is 8-bit asynchronous with a start bit, 8 data bits, and 1 stop bit. But the serial input of TC35i requires CMOS level, and serial output of 89C52 requires TTL level. In order to achieve the voltage conversion the system use the way of resistors sharing voltage. Fig. 4 nRF905 Application Schematic
Fig. 5 TC35i and MCU interface circuit
Software Design
The software system includes data acquisition module, temperature compensation module, and wireless transceiver module
Wireless sending program. NRF905 data sending process is as follows:
1) When having data to send, the microcontroller send the receiver's address and the data to nRF905 chronologically by the SPI interface.Then placed the data to be transmitted into TxBuf register, send WTP command to write the data to TX-Payload register, and send WTA command to write TX address to the TX-Address register.
2) The microcontroller set TRX_CE=1 and TX_EN=1 to stimulate nRF905 ShockBurstTM sending mode. When data transmission completed, the data ready pin is set high;
3) Beacause of AUTO_RETRAN being high, the data of nRF905 is constantly re-issued until TRX_CE=0.
4) when TRX_CE pin is set low, means the data transmission completed and nRF905 enter idlemode.
Wireless receiving program. NRF905 data receiving process is as follows:
1)When TRX_CE = 1 and TX_EN = 0, nRF905 enters ShockBurstTM receive mode
checking constantly and waiting for receiving data.
2)When nRF905 detect the carrier having same frequency band, the carrier detect pin will be
set high.
3)When nRF905 receive a matched address, the address matches pin will be set high.
4) When packet correctly received, the word head, address and CRC bits will automatically be removed, and the data ready pin will be set high.
5) MCU set TRX_CE to "0", and nRF905 enter to idle mode.
6) When all the data received, nRF905 set data ready pin and address matching pin to "0", and nRF905 turn to shutdown mode or ShockBurstTM transmitmode and receive mode.
Fig.6 Wireless data transmission flow chart
Fig.7 Wireless data receiving flow chart
Summary
Designed an equipment to detect the concentration of combustible gas, which has wireless transceiver functions and can send the alarm information to user’s mobile promptly through GSM.Experimental results show that the devices have high precision, stability and reliability. It can meet most applications which need real-time monitoring of combustible gas concentration.
References
[1] Liu S, Chen Q, Wang H G, eat. Electrical capacitance tomography for gas solids flow measurement for circulating fluidized beds [J].Flow Measurement and Instrumentation，2005，16(2-3):135-144.
[2] TGS 813-for the Detection of Combustible Gases [DB/OL].2009-08-12.
[3] Liu Wei, Chen HeXin，Zhang JunWei，etc. Intelligent control and alarm system based on TC35i. IEEE.2008 International Symposium on Computer Science and Computational Technology
(ISCSCT), Shanghai, 2008:80-83
Manufacturing Process and Equipment
10.4028/https://www.360docs.net/doc/2012150029.html,/AMR.694-697
Design of Combustible Gas Detection System Using Wireless Transmission Technology 10.4028/https://www.360docs.net/doc/2012150029.html,/AMR.694-697.1321
译文
使用无线的可燃气体检测系统的设计
传输技术
石家庄大学的经济学，河北，中国
zkzhlp@https://www.360docs.net/doc/2012150029.html,
关键词：TGS813，AT89S52单片机，DS18B20，nRF905，TC35i
摘要；可燃气体检测装置是在所提出的工作设计，使用无线收发器和GSM网络。该系统实现了气体浓度的无线传输，也可以发送报警信息到用户的移动发生异常时。该系统由两部分组成：一个主和奴隶。奴隶的功能是收集数据，处理数据和过渡到主数据。主的任务是接收数据并通过LED显示。信号采集由传感器TGS813和A/D转换器TLC2543完成。无线传输是通过无线收发芯片nRF905实现。由于传感器的精度受环境的影响，采用DS18B20实现温度补偿。与无线通信模块TC35i模块和GSM网络平台，我们可以发送报警信息到用户的移动迅速。
简介；
气体检测广泛应用于石油，化工，冶金，家庭，商场，加油站和其他地方。目前，如何快速、准确地监测有害气体是一个重要的问题。虽然气体检测技术已经比较成熟，但大多数产品有许多不足之处，如功能单一，操作复杂，笨重，昂贵的和低灵敏度。无线通信技术在气体检测领域的应用，可以解决在特殊环境下的远程监控问题，如高温，低温，有毒气体无法布线。
在工作中，可燃气体detectoris全功能（无线），简单，体积小，成本低，具有很高的灵敏度。该设备具有温度补偿算法，大大提高了系统的检测能力和精度，并能及时发送报警信息通过GSM网络到用户的手机上。
系统的设计
该系统由两部分组成，如图1所示
图1系统总体框图
下位机部分主要完成数据采集和无线传输。主控部分主要完成数据接收，显示和报警信息。
气体浓度信号是由可燃气体传感器产生微弱电信号采集。信号可以被放大和调理电路的稳定。然后A/D转换电路将模拟信号转换为数字信号，单片机可以处理。为了提高测量精度，降低了温度的影响，设计了温度补偿电路采集温度数据。AT89S52处理收集到的数据和发送通过无线收发模块的主数据。
主机接收数据并将其显示在LED。如果气体浓度异常，系统会发出报警信号并利用TC35I模块发送报警信息到用户的手机扬声器驱动。
硬件设计
信号采集和调理电路；图2显示了数据采集电路。是一个气敏电阻传感器TGS813。的电导率是由TGS813在空气中的可燃气体浓度的影响，浓度越大，较高的电导率。在系统R0，R9，R10和RS（在TGS813）形成一个桥电路将电阻的电压信号。运算放大器连接一个电阻R7和调节D1的电压跟随器组成的稳压电路为桥式供电。为了电压适应A/D转换器，电压通过运放B扩增和放大，可以通过调整电阻R11。
图2气体浓度信号采集电路
图3温度补偿电路
温度补偿电路；RS电阻受温度的影响较大。为了提高系统的精度，结果必须进行温度补偿和温度校正。在系统中，利用温度传感器DS1820采集温度信号，和用于温度校正软件的方法。
无线传输模块；无线收发器是单片射频收发器nRF905实现。单片机和nRF905实现数据和命令的交互通过SPI接口。典型应用示意图如图4所示。天线部分50Ω单端天线。通信频率为433MHz，运行电压为3.3V。的电阻值，电容器和电感器是由nRF905芯片的数据表确定
GSM短消息单元；TC35i和单片机的接口电路如图5所示。的
单片机与TC35I之间的通信是通过串行，和速率是9600。communicationsmode是8位异步一个起始位，8位数据位，1位停止。但TC35i串行输入要求的CMOS电平，和
89C52单片机的串行输出需要TTL电平。为了实现电压转换系统使用电阻共享电压的方式
图4 nRF905应用示意图
图5 TC35i模块与单片机的接口电路
软件设计
软件系统包括数据采集模块、温度补偿模块和无线收发模块
无线发送程序，nRF905发送数据的过程如下：
1）当有数据要发送，单片机把收信人的地址和数据以nRF905按时间顺序的SPI接口。然后把要发送的数据发送到发送缓冲器寄存器，WTP命令写入数据寄存器和发送TX的有效载荷，WTA命令写德克萨斯州TX地址寄存器地址。
2）微控制器设置trx_ce = 1和tx_en = 1刺激shockbursttm nRF905发送方式。当数据传输完成后，数据准备好引脚设置高；
3）的auto_retran高因为，nRF905芯片的数据是不断地重新发布到trx_ce = 0。
4）当trx_ce引脚设置低，意味着数据传输完成，进入idlemode nRF905。
无线接收程序，nRF905接收数据的过程如下：
1）当TRX _这= 1和TX _ = 0，nRF905 enters shockbursttm receive模式不断和等待接收数据的检查
2）当nRF905检测载体具有相同的频段，载波检测引脚将被设置高。
3）当nRF905接收相匹配的地址，地址匹配引脚将被设置高。
4）当分组正确接收，字头，地址和CRC比特将自动
除去，和数据准备好引脚将被设置高。
5）设置为“0”trx_ce单片机和nRF905，进入空闲模式。
6）当接收的所有数据集，nRF905的数据准备好引脚和地址匹配引脚到“0”，和
nRF905转向模式或关机shockbursttm transmitmode和接收模式。
图6无线数据传输的流程图
图7无线接收数据流程图
摘要
设计了一种检测可燃气体浓度的装置，具有无线收发器功能，可以发送报警信息到用户的移动迅速通过GSM实验结果表明，该装置具有较高的精度，稳定性和可靠性。它可以满足大多数这需要可燃气体浓度的实时监测中的应用。
工具书类
【1】刘氏，陈王Q，H G，吃。电容层析成像技术对气固两相流循环流化床的研究[J]测量。流量测量仪表，2005,16（3）：135-144。
[ 2 ] TGS 813的可燃气体检测2009-08-12 [分贝/ OL ]。
[ 3 ]刘薇，陈合新，张玮，基于智能控制及报警系统等ieee.2008 TC35i。计算机科学国际会议和计算技术（iscsct），上海，2008:80-83
机械制造工艺与设备
10.4028/https://www.360docs.net/doc/2012150029.html,/amr.694-697设计
使用无线传输技术的可燃气体检测系统的设计
10.4028/https://www.360docs.net/doc/2012150029.html,/amr.694-697.1321
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1、 外文原文 A: Fundamentals of Single-chip Microcomputer Th e si ng le -c hi p m ic ro co mp ut er i s t he c ul mi na ti on of both t h e de ve lo pm en t o f t he d ig it al co m pu te r an d th e i n te gr at ed c i rc ui t a rg ua bl y t h e to w m os t s ig ni f ic an t i nv en ti on s o f t he 20th c e nt ur y [1]. Th es e t ow ty pe s of ar ch it ec tu re a re fo un d i n s in g le -ch i p m i cr oc om pu te r. So m e em pl oy t he spl i t pr og ra m/da ta m e mo ry o f th e H a rv ar d ar ch it ect u re , sh ow n in Fi g.3-5A -1, o th ers fo ll ow t he p h il os op hy , wi del y a da pt ed f or ge n er al -p ur po se co m pu te rs a nd m i cr op ro ce ss o r s, o f ma ki ng n o log i ca l di st in ct ion be tw ee n p r og ra m an d d at a m e mo ry a s i n t he P r in ce to n ar ch ite c tu re , sh ow n i n F ig.3-5A-2. In g en er al te r ms a s in gl e -chi p m ic ro co mp ut er i s c h ar ac te ri ze d b y t h e i nc or po ra ti on o f a ll t he un it s of a co mp uter i n to a s in gl e d ev i ce , as s ho wn in Fi g3-5A -3. Fig.3-5A-1 A Harvard type Program memory Data memory CPU Input& Output unit memory CPU Input& Output unit
农业产业化组织的营销策略分析-外文翻译
外文翻译 原文 Title:Agricultural Industrialization Organization of Marketing Strategy Analysis Material source:2010 International Conference on Industry Engineering and Management Author:Zhao Yanhong, Ren Aihua Abstraet:Agricultural industrialization is the development direction of world agriculture, it is also the main form of the agricultural operation in developed countries. Vigorously develop the industrialization of agriculture is to enhance the competitiveness of China’s agricultu re is an effective means of marketing innovation in agriculture. It is related to the industrialization of agriculture an important factor in business success. In this paper, product, place, promotion, three organizations, the face of the industrialization of agriculture marketing innovation of the corresponding development proposals. Keywords:Product;Channel Innovation;Promotion 1 Introduction Although China has already established a number of agricultural industrialization organization, but very few successful cases, reason, the product can not sell that influence their development, an important factor. At present the industrialization of agriculture organizations in product development, sales channels and marketing methods. There are many ways to solve urgent problems, we can say, marketing has become a bottleneck restricting development of the organization. In this Paper, the development of marketing concept, mainly based on the content of the theory of 4P, from development to meet consumer demand for products. Innovation in the channel, flexible use of marketing mix and so the organization seeking to promote the industrialization of agriculture marketing of innovative measures. 2 Development of Products to Meet Consumer Demand 4C theory holds that companies should give top priority to the pursuit of customer satisfaction, then theagricultural industry of the organization must first develop a customer satisfaction products. Marketing believes that demand for the
模具毕业设计外文翻译(英文+译文)
Injection Molding The basic concept of injection molding revolves around the ability of a thermoplastic material to be softened by heat and to harden when cooled .In most operations ,granular material (the plastic resin) is fed into one end of the cylinder (usually through a feeding device known as a hopper ),heated, and softened(plasticized or plasticized),forced out the other end of the cylinder, while it is still in the form of a melt, through a nozzle into a relatively cool mold held closed under pressure.Here,the melt cools and hardens until fully set-up. The mold is then opened, the piece ejected, and the sequence repeated. Thus, the significant elements of an injection molding machine become: 1) the way in which the melt is plasticized (softened) and forced into the mold (called the injection unit); 2) the system for opening the mold and closing it under pressure (called the clamping unit);3) the type of mold used;4) the machine controls. The part of an injection-molding machine, which converts a plastic material from a sold phase to homogeneous seni-liguid phase by raising its temperature .This unit maintains the material at a present temperature and force it through the injection unit nozzle into a mold .The plunger is a combination of the injection and plasticizing device in which a heating chamber is mounted between the plunger and mold. This chamber heats the plastic material by conduction .The plunger, on each stroke; pushes unbelted plastic material into the chamber, which in turn forces plastic melt at the front of the chamber out through the nozzle The part of an injection molding machine in which the mold is mounted, and which provides the motion and force to open and close the mold and to hold the mold close with force during injection .This unit can also provide other features necessary for the effective functioning of the molding operation .Moving
自动化外文翻译
景德镇陶瓷学院 毕业设计(论文)有关外文翻 译 院系：机械电子工程学院 专业：自动化 姓名：肖骞 学号： 201010320116 指导教师：万军 完成时间： 2014.5.8 说明
1、将与课题有关的专业外文翻译成中文是毕业设计（论文）中的一个不可缺少的环节。此环节是培养学生阅读专业外文和检验学生专业外文阅读能力的一个重要环节。通过此环节进一步提高学生阅读专业外文的能力以及使用外文资料为毕业设计服务，并为今后科研工作打下扎实的基础。 2、要求学生查阅与课题相关的外文文献3篇以上作为课题参考文献，并将其中1篇（不少于3000字）的外文翻译成中文。中文的排版按后面格式进行填写。外文内容是否与课题有关由指导教师把关，外文原文附在后面。 3、指导教师应将此外文翻译格式文件电子版拷给所指导的学生，统一按照此排版格式进行填写，完成后打印出来。 4、请将封面、译文与外文原文装订成册。 5、此环节在开题后毕业设计完成前完成。 6、指导教师应从查阅的外文文献与课题紧密相关性、翻译的准确性、是否通顺以及格式是否规范等方面去进行评价。 指导教师评语： 签名： 年月日
TMS320LF2407, TMS320LF2406, TMS320LF2402 TMS320LC2406, TMS320LC2404, MS320LC2402 DSP CONTROLLERS The TMS320LF240x and TMS320LC240x devices, new members of the ‘24x family of digital signal processor (DSP) controllers, are part of the C2000 platform of fixed-point DSPs. The ‘240x devices offer the enhanced TMS320 architectural design of the ‘C2xx core CPU for low-cost, low-power, high-performance processing capabilities. Several advanced peripherals, optimized for digital motor and motion control applications, have been integrated to provide a true single chip DSP controller. While code-compatible with the existing ‘24x DSP controller devices, the ‘240x offers increased processing performance (30 MIPS) and a higher level of peripheral integration. See the TMS320x240x device summary section for device-specific features. The ‘240x family offers an array of memory sizes and different peripherals tailored to meet the specific price/performance points required by various applications. Flash-based devices of up to 32K words offer a reprogrammable solution useful for: ◆Applications requiring field programmability upgrades. ◆Development and initial prototyping of applications that migrate to ROM-based devices. Flash devices and corresponding ROM devices are fully pin-to-pin compatible. Note that flash-based devices contain a 256-word boot ROM to facilitate in-circuit programming. All ‘240x devices offer at least one event manager module which has been optimized for digital motor control and power conversion applications. Capabilities of this module include centered- and/or edge-aligned PWM generation, programmable deadband to prevent shoot-through faults, and synchronized analog-to-digital conversion. Devices with dual event managers enable multiple motor and/or converter
电气自动化专业毕业论文英文翻译
电厂蒸汽动力的基础和使用 1.1 为何需要了解蒸汽 对于目前为止最大的发电工业部门来说, 蒸汽动力是最为基础性的。 若没有蒸汽动力, 社会的样子将会变得和现在大为不同。我们将不得已的去依靠水力发电厂、风车、电池、太阳能蓄电池和燃料电池,这些方法只能为我们平日用电提供很小的一部分。 蒸汽是很重要的,产生和使用蒸汽的安全与效率取决于怎样控制和应用仪表,在术语中通常被简写成C&I(控制和仪表 。此书旨在在发电厂的工程规程和电子学、仪器仪表以 及控制工程之间架设一座桥梁。 作为开篇,我将在本章大体描述由水到蒸汽的形态变化,然后将叙述蒸汽产生和使用的基本原则的概述。这看似简单的课题实际上却极为复杂。这里, 我们有必要做一个概述:这本书不是内容详尽的论文,有的时候甚至会掩盖一些细节, 而这些细节将会使热力学家 和燃烧物理学家都为之一震。但我们应该了解,这本书的目的是为了使控制仪表工程师充 分理解这一课题,从而可以安全的处理实用控制系统设计、运作、维护等方面的问题。1.2沸腾:水到蒸汽的状态变化 当水被加热时,其温度变化能通过某种途径被察觉(例如用温度计 。通过这种方式 得到的热量因为在某时水开始沸腾时其效果可被察觉,因而被称为感热。 然而,我们还需要更深的了解。“沸腾”究竟是什么含义?在深入了解之前,我们必须考虑到物质的三种状态:固态,液态,气态。 (当气体中的原子被电离时所产生的等离子气体经常被认为是物质的第四种状态, 但在实际应用中, 只需考虑以上三种状态固态,
物质由分子通过分子间的吸引力紧紧地靠在一起。当物质吸收热量,分子的能量升级并且 使得分子之间的间隙增大。当越来越多的能量被吸收,这种效果就会加剧,粒子之间相互脱离。这种由固态到液态的状态变化通常被称之为熔化。 当液体吸收了更多的热量时,一些分子获得了足够多的能量而从表面脱离,这个过程 被称为蒸发(凭此洒在地面的水会逐渐的消失在蒸发的过程中,一些分子是在相当低的 温度下脱离的,然而随着温度的上升,分子更加迅速的脱离,并且在某一温度上液体内部 变得非常剧烈,大量的气泡向液体表面升起。在这时我们称液体开始沸腾。这个过程是变为蒸汽的过程,也就是液体处于汽化状态。 让我们试想大量的水装在一个敞开的容器内。液体表面的空气对液体施加了一定的压 力,随着液体温度的上升,便会有足够的能量使得表面的分子挣脱出去,水这时开始改变 自身的状态,变成蒸汽。在此条件下获得更多的热量将不会引起温度上的明显变化。所增 加的能量只是被用来改变液体的状态。它的效用不能用温度计测量出来,但是它仍然发生 着。正因为如此,它被称为是潜在的,而不是可认知的热量。使这一现象发生的温度被称为是沸点。在常温常压下,水的沸点为100摄氏度。 如果液体表面的压力上升, 需要更多的能量才可以使得水变为蒸汽的状态。 换句话说, 必须使得温度更高才可以使它沸腾。总而言之,如果大气压力比正常值升高百分之十,水必须被加热到一百零二度才可以使之沸腾。
美国农业合作社与农业产业化外文文献翻译中英文
美国农业合作社与农业产业化外文文献翻译中英文最新 （节选重点翻译） 英文 Managing uncertainty and expectations: The strategic response of U.S. agricultural cooperatives to agricultural industrialization Julie Hogeland Abstract The 20th century industrialization of agriculture confronted U.S. agricultural cooperatives with responding to an event they neither initiated nor drove. Agrarian-influenced cooperatives used two metaphors, “serfdom” and “cooperatives are like a family” to manage uncertainty and influence producer expectations by predicting industrialization's eventual outcome and cooperatives’ producer driven compensation. The serfdom metaphor alluded to industrialization's potential to either bypass family farmers, the cornerstone of the economy according to agrarian ideology, or to transform them into the equivalent of piece-wage labor as contract growers. The “family” metaphor reflects how cooperatives personalized the connection between cooperative and farmer-member to position themselves as the exact opposite of serfdom. Hypotheses advanced by Roessl (2005) and Goel (2013) suggest that intrinsic characteristics of family businesses such as a resistance to change and operating according to a myth of unlimited choice and
模具设计与制造外文翻译
The mold designing and manufacturing The mold is the manufacturing industry important craft foundation, in our country, the mold manufacture belongs to the special purpose equipment manufacturing industry. China although very already starts to make the mold and the use mold, but long-term has not formed the industry. Straight stabs 0 centuries 80's later periods, the Chinese mold industry only then drives into the development speedway. Recent years, not only the state-owned mold enterprise had the very big development, the three investments enterprise, the villages and towns (individual) the mold enterprise's development also rapid quietly. Although the Chinese mold industrial development rapid, but compares with the demand, obviously falls short of demand, its main gap concentrates precisely to, large-scale, is complex, the long life mold domain. As a result of in aspect and so on mold precision, life, manufacture cycle and productivity, China and the international average horizontal and the developed country still had a bigger disparity, therefore, needed massively to import the mold every year . The Chinese mold industry must continue to sharpen the productivity, from now on will have emphatically to the profession internal structure adjustment and the state-of-art enhancement. The structure adjustment aspect, mainly is the enterprise structure to the specialized adjustment, the product structure to center the upscale mold development, to the import and export structure improvement, center the upscale automobile cover mold forming analysis and the structure improvement, the multi-purpose compound mold and the compound processing and the laser technology in the mold design manufacture application, the high-speed cutting, the super finishing and polished the technology, the information direction develops . The recent years, the mold profession structure adjustment and the organizational reform step enlarges, mainly displayed in, large-scale, precise, was complex, the long life, center the upscale mold and the mold standard letter development speed is higher than the common mold product; The plastic mold and the compression casting mold proportion increases; Specialized mold factory quantity and its productivity increase;
自动化外文翻译
电气工程与自动化学院 本科毕业设计专业翻译资料（中文读书报告） 学生姓名：王超杰 专业班级：自动化12-06班 学号：311208002219 2016 年 6 月11 日
原文： Design of Combustible Gas Detection system using Wireless Transmission Technology Shijiazhuang Universities of Economics, Hebei, China zkzhlp@https://www.360docs.net/doc/2012150029.html, Keywords:TGS813, AT89S52, DS18B20, nRF905, TC35i Abstract.The detection device of combustible gas are designed in the presented work,using wireless transceiver and GSM network.The system realize the wireless transmission of the gas concentration,and also can send alarm information to user’s mobile when an exception occurs. The system consists of two parts: a master and slave. The function of the slave is to collect data, process data and transffer the data to the master.The taskof the master is to receive data and display it by LED. The signal acquisition is completed by sensor TGS813 and A/D converter TLC2543. The wireless transmission is achieved through wireless transceiver nRF905. Since the accuracy of the sensor is affected by the environment,using DS18B20 to achieve temperature compensation. And with wireless communication module TC35i and GSM network platform, we can send the alarm information to user’s mobile promptly. Introduction Gas detection is widely used in petroleum, chemical, metallurgy, family, shopping malls, gas stations and other places. Currently, how to monitor the hazardous gas fast and accurately are the important issues. Although the gas detection technology is relatively mature, but most products has many shortcomings, such as single function, operating complex, bulky, expensive and low sensitivity. Wireless communication technology applied to the gas monitoring field, can resolve the problem of remote monitoring in special environment, such as high temperature, low temperature, toxic gas.and unable to wiring . In the presented work, the combustible gas detectoris fully functional (with wireless transceiver), simple, small size, low cost, and has high sensitivity. The equipment can greatly improve the system's detection capability and accuracy with temperature compensation algorithm, and also can send alarm information to the user's mobile phone promptly through the GSM network. System design The system consists of two parts as shown in Figure 1. Fig. 1 Overall system block diagram