外文资料翻译
淮阴工学院
毕业设计(论文)外文资料翻译
系（院）：电子信息工程系
专业：测控技术与仪器
姓名：马宇
学号：1061203228
外文出处：Download from IEEE xplore of
(用外文写)huaiyin institute of technology library
附件： 1.外文资料翻译译文；2.外文原文。
指导教师评语：
所选内容与课题相关，对课题设计参考有一定的帮助；翻译难度一般，工作量适中；译文基本正确，语句通顺，但也存在部分错误。
总体评价：中
签名：
2010 年 4 月20 日注：请将该封面与附件装订成册。
附件1：外文资料翻译译文
数字式转速测量仪
摘要介绍了一种以MCS-51系列单片机8032为控制主体的数字式转速测量仪。该测量仪具有设计合理、精度高、测速范围宽、功能强、可靠性好、使用灵活方便等特点。文中详细介绍了该仪表的工作原理，给出了它的硬件原理图和软件流程图。关键词：数字式测量仪器；转速；单片机
转动体的速度是工业测控系统中的重要参数之一。机械式转速表在测量转速时，必须将转轴接触被测物体，以获得同步转速，通过内部齿轮变速后用表头指针指示转速大小。使用机械式转速表会干扰被测物体的运动，特别是当被测转动体质量很小时，测速表对转动体施加的压力就是一个不小的附加负载，这影响测量的准确性。本文介绍一种以8032单片微机为核心的测速仪。
1 转速测量仪原理
本测速仪的测速敏感器件采用红外线传感器，由专门的探测装置发射红外线，同时接受从被测物体反射回来的红外线，通过光电转换变为电脉冲信号，不影响物体的转动。发射管和接受管都固定在探测架上，通过透镜聚焦，半透明膜既能使反射的红外光线射向转动物体，又能使由转动物体反射回来的红外线通过半透明膜射向接受管。在转动体上沿圆周均匀贴上若干反射纸，它能定向反射红外线，使接受管接受到反射回来的红外线。
光电转换原理见图1。在光电三极管3DU5C上加一适当偏压，当3DU5C受红外线照射时，处于导通状态，A点为低压电平，3DG6截止，B点为高电平；当没有红外线照射时，光电三极管截止，A点呈现高电平，使3DG6集电极B点为低电平，B点的脉冲信号经过反相器1、2的整形，再经门3反相，便得到频率与转速大小相应成比例变化的转速脉冲信号。转速脉冲信号送入8032单片机的定时/计数器，经过单片机的软件处理计算出转速。
图1 光电转换原理图
本机在测量转速时采用了M/T法和定时法两种方法。M/T法是在检测时间Tc 内，根据转速脉冲m1和计时脉冲m2来计算转速。如在固定周期Tc内，计取转动脉冲fp和计时脉冲fc的脉冲个数分别为m1和m2，计时脉冲的频率为f，转动体每转输出的脉冲数为p，则转速n=60fm1/pm2(r/min)。定时法是在给定的时间间隔1 s内，对转速脉冲进行计数。如在1 s内测得的转速脉冲数为m1，转动体每转输出的脉冲个数，即极数为p，则转速n=60m1/p(r/min)。
2 转速测量仪的硬件结构
图2为由8032单片机构成的转速测量仪电路图。8032属于MCS-51系列单片机，与常用的8031芯片相比，8032多了一个功能较强的T2定时/计数器和128字节内部RAM，其中T2计数器具有16位自动重载和捕获能力，既可作定时/计数用，又可作为波特率发生器用。本系统T2用于定时，即计取定时脉冲信号，定时脉冲信号直接从8032芯片的地址锁存信号端ALE引出，并经过74LS74双D触发器两分频后获得。当晶振采用6 MHz时，定时脉冲的频率fc为0.5 MHz。T0计数器计取转速脉冲fp，T1计数器用于计取定时脉冲fc，触发器DFF1，DFF2和与门1,2,3,4组成计数控制电路，能使T0和T1计数器同时启停。系统采用动态显示方式。P0口通过带允许控制端的8D锁存器74LS377扩展了一个8位输出口，作为5位LED 数码管显示的段选码数据线。P1.3-P1.75根口线作为五位LED显示的位选线。P3.0、P3.1接S1和S4开关，S1为极数P设定选择开关，S4为极数输入脉冲键。P3.2和P3.3分别接S2和S3开关，S2开关为测速方法选择键，选择用M/T法测速，还是用定时法测速。S3为转速/频率选择开关，用来选择测转速还是测频率。当用定时法测转速时，系统可以很方便地测出所测频率。
3 软件设计及抗干扰措施
系统的程序设计主要包括主程序、中断程序、代码转换子程序、显示子程序等。两种测速方法硬件结构完全相同，只是软件流程不同，通过P3.2口来设定测速方法。下面分别论述两种测速方法的工作原理。
M/T法中，首先由8032的P1.1端输出启动脉冲信号，该启动脉冲清零DFF1和DFF2两个触发器，使Q1端输出低电平，封锁门2、3、4，Q-1端为高电平打开门1，而触发器DFF2的Q-2端输出为高电平，为启动工作做好准备。当接受到转速脉冲信号fp的上升沿时，触发器DFF1翻转，Q-1为低电平，封锁门1，Q1为高电平，打开门2、3、4，从而使T2开始定时，m1，m2同时开始计数。当T2定时到100 ms时，向8032申请中断。在中断程序中，8032的P1.2端输出停止脉冲信号，置位触发器DFF2，Q-2端输出低电平，封锁门2、3、4，T0、T1同时停止计数。同时在中断程序中读出转速信号脉冲数m1和定时信号脉冲数m2，在主程序中根据m1、m2，P和f算出转速n=60fm1/pm2，并转换为BCD码，查表送至数码管显示，完成一次数据的采集和显示。
在定时法中，由于要产生1 s的定时信号，而本系统中定时最大值为131 ms，故在定时法中，采取连续定时10次100 ms的方法，当到了100 ms定时时，定时器T2溢出向8032申请中断。在中断程序中对中断次数进行累计，如果累计中断次数未到10次，则不作任何运算就返回，T2继续下一次的100ms的定时，T0继续计数转速脉冲，当中断次数达到10次时，在中断程序中，置位P1.2，停止计数，并且读出T0的计数值m1，在主程序中进行相应运算算出转速，并转换为BCD码，送LED显示。这里定时计数器采用了具有16位自动重装载功能的T2计数器，当T2溢出产生中断的同时，计数器自动重载计数初值，继续定时。因此它的定时是连续的，不受响应中断和处理中断程序的影响。而如果采用没有重载功能的定时器如T0或T1，则当定时器溢出时，须在响应中断后，在中断程序中重置定时器初值。定时器的定时是断续的，影响定时精度，继而影响测速精度。可见采用8032中的T2计数器定时是本系统一个特点，它能显著提高测速精度。本测速仪在0-49r/min范围内，精度可达±0.1 r/min,在50-99 999r/min范围内，精度可达±1 r/min。
本测速仪可以测量不同极数的脉冲发生器发生的脉冲，如前述的红外线探测器，当改变贴在转动体上反射纸的数量时，转动体每转发出的脉冲数p也相应改变，此时如果仍按照程序中原定的p值进行计算，就会运算出错。因此本系统提供了现
场设置极数的功能：P3.0口接极数设定选择开关，当P3.0高电平时，表明需要设置极数，此时系统等待由P3.1口输进的脉冲信号，每一个脉冲信号可使系统的极数寄存器数值加1，并显示在LED数码管上。
在定时法测速时，当不进行n=60m1/p的运算，直接将1 s内的转速脉冲数m1变换为BCD码显示，所得的数值显然就是输入脉冲信号的频率。因此系统设置了转速/频率选择功能。P3.3口接转速/频率选择开关S3，当P3.3为高电平时，表示测频率。
同时，系统软件还设置了一些逻辑错误诊断功能，如当转速超过99 999 r/min，系统将显示PPPPP，表示超出本测速仪所测范围，又如当在M/T法测速时，选择了测频率，则显示EEEEE，提示用户出错等。
由于测速仪一般都在工业生产现场工作，工作环境干扰来源多，因此在设计中，采用了抗干扰措施，如电源滤波、去耦、注意地线的走向，接地点的安排等硬件抗干扰办法，以CPU、RAM自检、软件冗余、软件陷阱等软件抗干扰技术。
图2 数字式转速测量仪电路图
参考文献
[1] Yurish S.Y., Kirianaki N.V. Design of High Performances Digital Tachometers and Tachometric Systems Based on the Method of the Depended Count, In Proceedings of the VII-th International Conference CADSM’ 2003, Lviv-Slavsko, UKRAINE, 18-22
February, 2003
[2] Kirianaki N.V., Deynega V.P., Yurish S.Y., Microprocessor Tachometers of New Generation for Turbogenerators of Thermal and Nuclear Electric Power Stations, Automatic, Measurements and Control, 1995, No. 292, pp. 52-60.
[3] Yurish S.Y., Kirianaki N.V., Shpak N.O., Novel Rotation Speed Measurement Concept for ABS Appropriated for Microsystem Creation. In: Advanced Microsystems for Automotive Applications 99 (Ed. by Ricken D.E. and Gesner W., Springer, 1999, pp.215-223.
附件2：外文原文（复印件）
Digital Meter for Measuring Rotational Speed
Abstract A digital meter for measuring the rotational speed is introduced in this paper. It is controlled by an MCS-51 series single-chip microcomputer 8032. It contains the following features: rational design, high accuracy, wide measurability range and powerful function and dependability. Moreover, it is very nimble and convenient to use. The work principle is presented in detail in the paper and the block diagram and program flowchart are given as well.
Key works: digital measuring apparatus; rotation speed; single-chip micro-computer The rotor speed control system of industry is one of the important parameters. Mechanical tachometer measuring speed, the rotor contact with the measured object must be to get the synchronous speed, through the internal gear shift instruction after the pointer speed with the size of the header. Use of mechanical tachometer measured object can interfere with movement, especially when measured rotor mass is very small, speed tables on the rotor pressure is not a small additional load, which affects the measurement accuracy. This paper describes a 8032 single-chip microcomputer as the core to the non-contact Digital Tachometer.
1 speed measuring principle
The gun speed-sensitive devices with infrared sensors, launched by the specialized infrared detection devices, while receiving reflected back from the measured object infrared, photoelectric conversion into electrical pulses through the signal, does not affect the rotation of the object. Tubes and pipes are fixed in the detection of acceptable shelf, through the lens focus, semi-transparent film not only to the reflected infrared light fired rotating objects, they can rotate the object by the reflected infrared light through the translucent membrane back fired for management. Along the circumference of a rotating body even paste some reflection paper, it directed reflection infrared to receive the reflected acceptance of the infrared control.
Photovoltaic conversion shown in Figure In the optical triode 3DU5C adding an appropriate bias, when 3DU5C by infrared irradiation, at the conduction state, A point for
the low level, 3DG6 end, B point is high; when no infrared radiation, the photoelectric transistor closed A high point presentation, so 3DG6 low collector point B, B point of the pulse signal through the inverter 1,2 plastic, and then the door 3 RP, frequency and speed will be proportional to the size of the corresponding changes The speed pulse signal. Speed pulse signal into the 8032 microcontroller timer / counter, through the microcontroller to calculate speed software processing.
Figure 1 Schematic photoelectric conversion
When the machine used in the measurement speed M / T method and timing method were used. M/T M / T method is the detection time Tc, the time according to speed pulse m1 and m2 to calculate the speed pulse. If a fixed period Tc, the total time taken and pulse rotation pulse fp fc's Pulse on m1 and m2, timing pulse frequency f, rotor output pulses per revolution for the p, the speed n = 60fm1 / pm2 (r / min). Such as the speed measured over 1 s pulses for the m1, rotor output pulse number per revolution, that great number of p, the speed n = 60m1 / p (r / min).
2 hardware speed measurement instrument
Figure 2 constitute the grounds of speed 8032 MCU measuring circuit. 8032 is MCS-51 series single chip, compared with the common 8031 chip, a feature more than 8032 strong T2 timer / counters and 128 bytes of internal RAM, which T2 counter with 16-bit auto-reload and capture, can for timer / counter with, but also used as a baud rate generator. The system used for time T2, which take into account regular pulse, regular pulse signal directly from the 8032 chip address latch signal ALE client leads, and through the 74LS74 dual D flip-flop frequency, was two points. When using 6 MHz
crystal oscillator, the time pulse frequency fc is 0.5 MHz. T0 accrual speed pulse counter fp, T1 time pulse counter for taking into account fc, trigger DFF1, DFF2 and 1,2,3,4 component count and gate control circuit, can also start and stop counters T0 and T1. P0 port to allow control through the end of 8D with latch 74LS377 extends an 8-bit output, as a five segment LED digital display of the data line selection code. P3.0, P3.1 access switches S1 and S4, S1 for the very few P set selector switch, S4 input pulse for the very few keys. P3.2 and P3.3 are connected S2 and S3 switch, S2 switch method for the speed selection key; select the use of M / T method speed, or velocity measurement with time. S3 for the speed frequency select switch, to select the measuring speed or frequency measurements. When using regular method to measure the speed, the system can be easily measured by measuring the frequency.
3 software design and anti-interference measures
System programming includes the main program, interrupt procedures, code conversion routines, display routines, etc. The hardware structure of two measurement methods are identical, but different software process, to set the speed through the P3.2 port approach. The following two measurement methods were discussed works.
M / T method, first of all by the end of 8032 the P1.1 output start pulse signal, the start pulse cleared DFF1 and DFF2 two triggers, so that Q1 ended output low, blocking the door 2,3,4, Q- 1 side open the door for the high one, and trigger DFF2 the Q-2-ended output is high, ready for the start of work. When the speed pulse signal fp receives the rising edge, the flip-flop DFF1 turn, Q-1 is low, blocking the door 1, Q1 is high, open the door 2,3,4, so that start time T2, m1, m2 and started counting. In the interrupt program, the P1.2 8032 ended output pulse signal to stop, set bit trigger DFF2, Q-2 low-side outputs, blocking the door 2,3,4, T0, T1 and stop counting. Interrupt the program while reading speed signal pulses and timing signal pulses m1 m2, in the main program, in accordance with m1, m2, P and f calculated speed n = 60fm1/pm2, and converted to BCD code sent to the digital look-up table display, complete a data collection and display.
In the regular method, due to the timing signal generated 1 s, while the maximum time the system 131 ms, it is the law in time to take 10 consecutive 100 ms time method, when the time to 100 ms, the timer T2 overflow interrupt to the 8032 application.
Interrupt in the interrupt process of the cumulative number of times, if the cumulative number of times until they break 10, not to make any operation on the return, T2 to the next 100ms the time, T0 to count speed pulse, when the interrupt when the number reached 10 in interrupt the program, set bit P1.2, stop counting, and reading the count value T0 m1, corresponding in the main program to calculate the speed of operation, and converted to BCD code, send LED display. Time here with 16-bit counter with auto-loading feature of the T2 counter, when T2 overflow interrupt the same time, the counter counts automatically reload the initial value, continue to regularly. So it's time is continuous, without interruption and response procedures for dealing with the impact of disruption. If not overloaded by features such as timers T0 or T1, then when the timer overflow, it should be in response to failure, reset the timer interrupt program, the initial value. Timer timing is intermittent, the impact of timing accuracy, thereby affecting measurement precision. Visible by 8032 in the T2 counter timer is a feature of the system, it can significantly improve measurement precision. The guns range in 0-49r/min accuracy up to ± 0.1 r / min, at 50-99 999r/min range of accuracy up to ± 1 r / min.
The gun can measure the number of different pole pulse generator pulse occurs, such as infrared detectors above, when changing the rotating body attached to the amount of reflection paper, issued by the rotor per revolution pulse number p is also changed accordingly, At this point, if still in accordance with the procedures in the original p value calculation, calculation error will be. Therefore, the system provides very few of the features set the scene: P3.0 I take very few set selector switch, when P3.0 is high time that need to set the pole, then the system waiting for input into the mouth by the P3.1 pulse signal, each pulse makes the system very few register value plus 1, and displayed in the LED digital tube.
Velocity measurement at the time, and when not to n = 60m1 / p the operators directly to the speed of 1 s pulses m1 transformed into BCD code shows that the value obtained is obviously the input pulse frequency. Therefore, the system set up speed frequency options. P3.3 port access speed frequency select switch S3, when P3.3 is high time that test frequency.
Meanwhile, the system software has set a number of logical fault diagnosis
functions, such as speeds above 99 999 r / min, the system will display PPPPP, that go beyond the scope of this gun is measured, and as if the M / T velocity measurement, the Select the measurement frequency, it shows EEEEE, prompts the user error and so on.
As the gun is generally in the industrial field in the working environment of sources of interference, so in the design, using anti-jamming measures, such as power supply filtering, decoupling, pay attention to the trend of ground, then the locations and other hardware interference approach to CPU, RAM self-test, software redundancy, software, software such as anti-jamming technology trap.
Figure 2 Circuit Digital Speed Meter
References
[1] Yurish S.Y., Kirianaki N.V. Design of High Performances Digital Tachometers and Tachometric Systems Based on the Method of the Depended Count, In Proceedings of the VII-th Int ernational Conference CADSM’ 2003, Lviv-Slavsko, UKRAINE, 18-22 February, 2003
[2] Kirianaki N.V., Deynega V.P., Yurish S.Y., Microprocessor Tachometers of New Generation for Turbogenerators of Thermal and Nuclear Electric Power Stations, Automatic, Measurements and Control, 1995, No. 292, pp. 52-60.
[3] Yurish S.Y., Kirianaki N.V., Shpak N.O., Novel Rotation Speed Measurement
Concept for ABS Appropriated for Microsystem Creation. In: Advanced Microsystems for Automotive Applications 99 (Ed. by Ricken D.E. and Gesner W., Springer, 1999, pp.215-223.
1外文文献翻译原文及译文汇总
华北电力大学科技学院 毕业设计（论文）附件 外文文献翻译 学号：121912020115姓名：彭钰钊 所在系别：动力工程系专业班级：测控技术与仪器12K1指导教师：李冰 原文标题：Infrared Remote Control System Abstract 2016 年 4 月 19 日
红外遥控系统 摘要 红外数据通信技术是目前在世界范围内被广泛使用的一种无线连接技术，被众多的硬件和软件平台所支持。红外收发器产品具有成本低，小型化，传输速率快，点对点安全传输，不受电磁干扰等特点，可以实现信息在不同产品之间快速、方便、安全地交换与传送，在短距离无线传输方面拥有十分明显的优势。红外遥控收发系统的设计在具有很高的实用价值，目前红外收发器产品在可携式产品中的应用潜力很大。全世界约有1亿5千万台设备采用红外技术，在电子产品和工业设备、医疗设备等领域广泛使用。绝大多数笔记本电脑和手机都配置红外收发器接口。随着红外数据传输技术更加成熟、成本下降，红外收发器在短距离通讯领域必将得到更广泛的应用。 本系统的设计目的是用红外线作为传输媒质来传输用户的操作信息并由接收电路解调出原始信号，主要用到编码芯片和解码芯片对信号进行调制与解调，其中编码芯片用的是台湾生产的PT2262，解码芯片是PT2272。主要工作原理是：利用编码键盘可以为PT2262提供的输入信息，PT2262对输入的信息进行编码并加载到38KHZ的载波上并调制红外发射二极管并辐射到空间，然后再由接收系统接收到发射的信号并解调出原始信息，由PT2272对原信号进行解码以驱动相应的电路完成用户的操作要求。 关键字：红外线；编码；解码；LM386；红外收发器。 1 绪论
计算机专业外文文献及翻译
微软Visual Studio 1微软Visual Studio Visual Studio 是微软公司推出的开发环境，Visual Studio可以用来创建Windows平台下的Windows应用程序和网络应用程序，也可以用来创建网络服务、智能设备应用程序和Office 插件。Visual Studio是一个来自微软的集成开发环境IDE，它可以用来开发由微软视窗，视窗手机，Windows CE、.NET框架、.NET精简框架和微软的Silverlight支持的控制台和图形用户界面的应用程序以及Windows窗体应用程序，网站，Web应用程序和网络服务中的本地代码连同托管代码。 Visual Studio包含一个由智能感知和代码重构支持的代码编辑器。集成的调试工作既作为一个源代码级调试器又可以作为一台机器级调试器。其他内置工具包括一个窗体设计的GUI应用程序，网页设计师，类设计师，数据库架构设计师。它有几乎各个层面的插件增强功能，包括增加对支持源代码控制系统（如Subversion和Visual SourceSafe）并添加新的工具集设计和可视化编辑器，如特定于域的语言或用于其他方面的软件开发生命周期的工具（例如Team Foundation Server的客户端：团队资源管理器）。 Visual Studio支持不同的编程语言的服务方式的语言，它允许代码编辑器和调试器（在不同程度上）支持几乎所有的编程语言，提供了一个语言特定服务的存在。内置的语言中包括C/C + +中（通过Visual C++）,https://www.wendangku.net/doc/72627655.html,（通过Visual https://www.wendangku.net/doc/72627655.html,），C＃中（通过Visual C＃）和F＃（作为Visual Studio 2010），为支持其他语言，如M,Python,和Ruby等，可通过安装单独的语言服务。它也支持的 XML/XSLT,HTML/XHTML ,JavaScript和CSS.为特定用户提供服务的Visual Studio也是存在的：微软Visual Basic，Visual J＃、Visual C＃和Visual C++。 微软提供了“直通车”的Visual Studio 2010组件的Visual Basic和Visual C＃和Visual C + +，和Visual Web Developer版本，不需任何费用。Visual Studio 2010、2008年和2005专业版，以及Visual Studio 2005的特定语言版本（Visual Basic、C++、C＃、J＃），通过微软的下载DreamSpark计划，对学生免费。 2架构 Visual Studio不支持任何编程语言，解决方案或工具本质。相反，它允许插入各种功能。特定的功能是作为一个VS压缩包的代码。安装时，这个功能可以从服务器得到。IDE提供三项服务：SVsSolution，它提供了能够列举的项目和解决方案; SVsUIShell，它提供了窗口和用户界面功能（包括标签，工具栏和工具窗口）和SVsShell，它处理VS压缩包的注册。此外，IDE还可以负责协调和服务之间实现通信。所有的编辑器，设计器，项目类型和其他工具都是VS压缩包存在。Visual Studio 使用COM访问VSPackage。在Visual Studio SDK中还包括了管理软件包框架(MPF)，这是一套管理的允许在写的CLI兼容的语言的任何围绕COM的接口。然而，MPF并不提供所有的Visual Studio COM 功能。
外文翻译
Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the
外文资料及其翻译
A Wavelet Based Approach for Fast Detection of Internal Fault in Power Transformers The power transformer is one of the most expensive elements of power system and its protection is an essential part of the overall system protection strategy. The differential protection provides the best protection for power transformer. Its operation principle is based on this point that the differential current during an internal fault is higher than normal condition. But, a large transient current (inrush current) can cause mal-operation of differential relays. Then, studies for the improvement of the transformer protection have focused on discrimination between internal short circuit faults and inrush currents in transformers. The magnetizing inrush current has a large second order harmonic component in comparison to internal faults. Therefore , some transformer protection systems are designed to halt operating during the inrush current by sensing this large second order harmonic. The second harmonic component in the magnetizing inrush currents tend to be relatively small in modern large power transformers because of improvements in the power transformer core materials. Also , it has been seen that the fault current can contain higher second order harmonics than the inrush current due to nonlinear fault resistance, CT saturation .the distributed capacitance in the transmission line, which transformer is connected to, or due to the use of extra high voltage underground cables. Various methods have been suggested for overcoming this protection system mal-operation. This paper presents a wavelet based method for discrimination among inrush current, internal short circuit ,external short circuit and energizing and it is not affected by CT saturation and it is able to detect internal faults while transformer energization. Unlike Artificial Neural Network and Fuzzy logic based algorithms. This approach is not system dependent. The operating time of the scheme is less than 10ms. The Daubechies mother wavelet is used with a sample rate of 5 kHz. Then , the differential currents of the three phases are decomposed into two details and only the second level will be considered by using db5 mother wavelet. Discrete Wavelet Transform The wavelet transform is a powerful tool to extract information from the non-stationary signals simultaneously in both time and frequency domains. The ability of the wavelet transform to focus on short time intervals for high-frequency components and long intervals for low-frequency components improves the analysis
土木外文翻译原文和译文
A convection-conduction model for analysis of the freeze-thaw conditions in the surrounding rock wall of a tunnel in permafrost regions Abstract Based on the analyses of fundamental meteorological and hydrogeological conditions at the site of a tunnel in the cold regions, a combined convection-conduction model for air flow in the tunnel and temperature field in the surrounding has been constructed. Using the model, the air temperature distribution in the Xiluoqi No. 2 Tunnel has been simulated numerically. The simulated results are in agreement with the data observed. Then, based on the in situ conditions of sir temperature, atmospheric pressure, wind force, hydrogeology and engineering geology, the air-temperature relationship between the temperature on the surface of the tunnel wall and the air temperature at the entry and exit of the tunnel has been obtained, and the freeze-thaw conditions at the Dabanshan Tunnel which is now under construction is predicted. Keywords: tunnel in cold regions, convective heat exchange and conduction, freeze-thaw. A number of highway and railway tunnels have been constructed in the permafrost regions and their neighboring areas in China. Since the hydrological and thermal conditions changed after a tunnel was excavated，the surrounding wall rock materials often froze, the frost heaving caused damage to the liner layers and seeping water froze into ice diamonds，which seriously interfered with the communication and transportation. Similar problems of the freezing damage in the tunnels also appeared in other countries like Russia, Norway and Japan .Hence it is urgent to predict the freeze-thaw conditions in the surrounding rock materials and provide a basis for the design，construction and
毕业设计外文翻译资料
外文出处： 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题： JDBC接口技术 译文： JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface应用程序设计接口）。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC，很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢？如果有，那么它们之间又是怎样的关系呢？ ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的，用C语言实现的，标准应用程序数据接口。通过ODBCAPI，应用程序可以存取保存在多种不同数据库管理系统（DBMS）中的数据，而不论每个DBMS使用了何种数据存储格式和编程接口。 1．ODBC的结构模型 ODBC的结构包括四个主要部分：应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口：屏蔽不同的ODBC数据库驱动器之间函数调用的差别，为用户提供统一的SQL编程接口。 驱动器管理器：为应用程序装载数据库驱动器。 数据库驱动器：实现ODBC的函数调用，提供对特定数据源的SQL请求。如果需要，数据库驱动器将修改应用程序的请求，使得请求符合相关的DBMS所支持的文法。 数据源：由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器，以便ODBC函数调用，但是数据库驱动器本身也执行ODBC函数调用，并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时，数据库驱动器能管理通信协议。当建立起与数据源的连接时，数据库驱动器便能处理应用系统向DBMS发出的请求，对分析或发自数据源的设计进行必要的翻译，并将结果返回给应用系统。 2．JDBC的诞生 自从Java语言于1995年5月正式公布以来，Java风靡全球。出现大量的用java语言编写的程序，其中也包括数据库应用程序。由于没有一个Java语言的API，编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥，比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱，越来越多的公司在Java程序开发上投入的精力日益增加，对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处，比如它并不容易使用，没有面向对象的特性等等，SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1．x 版本中，JDBC只是一个可选部件，到了JDK1．1公布时，SQL类包（也就是JDBCAPI）
毕业设计外文资料翻译译文
附件1：外文资料翻译译文 包装对食品发展的影响 一个消费者对某个产品的第一印象来说包装是至关重要的，包括沟通的可取性，可接受性，健康饮食形象等。食品能够提供广泛的产品和包装组合，传达自己加工的形象感知给消费者，例如新鲜包装/准备，冷藏，冷冻，超高温无菌，消毒（灭菌），烘干产品。 食物的最重要的质量属性之一，是它的味道，其影响人类的感官知觉，即味觉和嗅觉。味道可以很大程度作退化的处理和/或扩展存储。其他质量属性，也可能受到影响，包括颜色，质地和营养成分。食品质量不仅取决于原材料，添加剂，加工和包装的方法，而且其预期的货架寿命（保质期）过程中遇到的分布和储存条件的质量。越来越多的竞争当中，食品生产商，零售商和供应商；和质量审核供应商有显着提高食品质量以及急剧增加包装食品的选择。这些改进也得益于严格的冷藏链中的温度控制和越来越挑剔的消费者。 保质期的一个定义是：在食品加工和包装组合下，在食品的容器和条件，在销售点分布在特定系统的时间能保持令人满意的食味品质。保质期，可以用来作为一个新鲜的概念，促进营销的工具。延期或保质期长的产品，还提供产品的使用时间，方便以及减少浪费食物的风险，消费者和/或零售商。包装产品的质量和保质期的主题是在第3章中详细讨论。 包装为消费者提供有关产品的重要信息，在许多情况下，使用的包装和/或产品，包括事实信息如重量，体积，配料，制造商的细节，营养价值，烹饪和开放的指示，除了法律准则的最小尺寸的文字和数字，有定义的各类产品。消费者寻求更详细的产品信息，同时，许多标签已经成为多语种。标签的可读性是为视障人士的问题，这很可能成为一个对越来越多的老年人口越来越重要的问题。 食物的选择和包装创新的一个主要驱动力是为了方便消费者的需求。这里有许多方便的现代包装所提供的属性，这些措施包括易于接入和开放，处置和处理，产品的知名度，再密封性能，微波加热性，延长保质期等。在英国和其他发达经济体显示出生率下降和快速增长的一个相对富裕的老人人口趋势，伴随着更加苛
【最新推荐】应急法律外文文献翻译原文+译文
文献出处：Thronson P. Toward Comprehensive Reform of America’s Emergency Law Regime [J]. University of Michigan Journal of Law Reform, 2013, 46(2). 原文 TOWARD COMPREHENSIVE REFORM OF AMERICA’S EMERGENCY LAW REGIME Patrick A. Thronson Unbenownst to most Americans, the United States is presently under thirty presidentially declared states of emergency. They confer vast powers on the Executive Branch, including the ability to financially incapacitate any person or organization in the United States, seize control of the nation’s communications infrastructure, mobilize military forces, expand the permissible size of the military without congressional authorization, and extend tours of duty without consent from service personnel. Declared states of emergency may also activate Presidential Emergency Action Documents and other continuity-of-government procedures, which confer powers on the President—such as the unilateral suspension of habeas corpus—that appear fundamentally opposed to the American constitutional order.
外文文献及翻译
文献翻译 原文 Combining JSP and Servlets The technology of JSP and Servlet is the most important technology which use Java technology to exploit request of server, and it is also the standard which exploit business application .Java developers prefer to use it for a variety of reasons, one of which is already familiar with the Java language for the development of this technology are easy to learn Java to the other is "a preparation, run everywhere" to bring the concept of Web applications, To achieve a "one-prepared everywhere realized." And more importantly, if followed some of the principles of good design, it can be said of separating and content to create high-quality, reusable, easy to maintain and modify the application. For example, if the document in HTML embedded Java code too much (script), will lead the developed application is extremely complex, difficult to read, it is not easy reuse, but also for future maintenance and modification will also cause difficulties. In fact, CSDN the JSP / Servlet forum, can often see some questions, the code is very long, can logic is not very clear, a large number of HTML and Java code mixed together. This is the random development of the defects. Early dynamic pages mainly CGI (Common Gateway Interface, public Gateway Interface) technology, you can use different languages of the CGI programs, such as VB, C / C + + or Delphi, and so on. Though the technology of CGI is developed and powerful, because of difficulties in programming, and low efficiency, modify complex shortcomings, it is gradually being replaced by the trend. Of all the new technology, JSP / Servlet with more efficient and easy to program, more powerful, more secure and has a good portability, they have been many people believe that the future is the most dynamic site of the future development of technology. Similar to CGI, Servlet support request / response model. When a customer submit a request to the server, the server presented the request Servlet, Servlet responsible for handling requests and generate a response, and then gave the server, and then from the server sent to
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河南科技学院新科学院 2013届本科毕业生论文（设计） 英文文献及翻译 Foreign capital inflows and welfare in an economy with imperfect competition 学生姓名：王艳杰 所在院系：经济系 所学专业：国际经济与贸易 导师姓名：侯黎杰 完成时间：2013年4月15日
Foreign capital inflows and welfare in an economy with imperfect competition Abstract:This paper examines the resource allocational and welfare effects of exogenous inflows of foreign capital in a general-equilibrium model with oligopolistic competition and unemployment. Although the welfare impact for the short run is ambiguous and dependent upon the strength of excess profits and scale economies relative to unemployment in manufacturing, in the long run additional inflows of foreign capital always improve national welfare with capital mobility. Hence, attracting foreign capital remains a sound policy for economies characterized by imperfect competition, scale economies,and regional unemployment. Keywords: International capital mobility; Imperfect competition; Welfare 1.Introduction The welfare effects of exogenous inflows of foreign capital in the presence of trade restrictions have been extensively studied. Brecher and Diaz Alejandro (1977) show that when imports are subject to tariffs, an introduction of fo reign capital inflows accentuates the tariff distortion and hence reduces national welfare if the import-competing sector is relatively capital-intensive. In contrast, Dei (1985) shows that when imports are restricted by quotas,foreign capital inflows in the presence of foreign-owned capital always improve welfare by depressing the rental and so lowering the payments to existing foreign-owned capital. Recently, Neary (1981), using a common framework for both tariffs and quotas, obtains more general results of foreign capital inflows; the welfare effect of such inflows depends crucially on whether foreign-owned capital exists initially in the home country. In addition, Khan (1982) and Grinols (1991) have examined the effects of foreign capital inflows for a generalized Harris-Todaro economy under tariff protection. Khan finds that the result by Brecher and Diaz Alejandro is still valid even in the presence of unemployment, whereas Grinols argues that increased foreign capital need not be detrimental to welfare if the opportunity costs of labor are sufficiently low. Noteworthy is that the models used by these authors are all based upon the premise of perfect competition along with constant returns-to-scale technology. Although perfect competition serves as a useful assumption in crystallizing theoretical insights, it nevertheless fails to depict many of the real-world phenomena. The real-world economy is characterized, to a large extent, by imperfect competition and economies of scale. The policy implications of imperfect competition and economies
毕业设计(论文)外文资料翻译〔含原文〕
南京理工大学 毕业设计(论文)外文资料翻译 教学点：南京信息职业技术学院 专业：电子信息工程 姓名：陈洁 学号： 014910253034 外文出处：《 Pci System Architecture 》 (用外文写) 附件： 1.外文资料翻译译文；2.外文原文。 指导教师评语： 该生外文翻译没有基本的语法错误，用词准确，没 有重要误译，忠实原文；译文通顺，条理清楚，数量与 质量上达到了本科水平。 签名： 年月日 注：请将该封面与附件装订成册。
附件1：外文资料翻译译文 64位PCI扩展 1.64位数据传送和64位寻址：独立的能力 PCI规范给出了允许64位总线主设备与64位目标实现64位数据传送的机理。在传送的开始，如果回应目标是一个64位或32位设备，64位总线设备会自动识别。如果它是64位设备，达到8个字节（一个4字）可以在每个数据段中传送。假定是一串0等待状态数据段。在33MHz总线速率上可以每秒264兆字节获取（8字节／传送＊33百万传送字／秒），在66MHz总线上可以528M字节／秒获取。如果回应目标是32位设备，总线主设备会自动识别并且在下部4位数据通道上（AD[31::00]）引导，所以数据指向或来自目标。 规范也定义了64位存储器寻址功能。此功能只用于寻址驻留在4GB地址边界以上的存储器目标。32位和64位总线主设备都可以实现64位寻址。此外，对64位寻址反映的存储器目标（驻留在4GB地址边界上）可以看作32位或64位目标来实现。 注意64位寻址和64位数据传送功能是两种特性，各自独立并且严格区分开来是非常重要的。一个设备可以支持一种、另一种、都支持或都不支持。 2.64位扩展信号 为了支持64位数据传送功能，PCI总线另有39个引脚。 ●REQ64#被64位总线主设备有效表明它想执行64位数据传送操作。REQ64#与FRAME#信号具有相同的时序和间隔。REQ64#信号必须由系统主板上的上拉电阻来支持。当32位总线主设备进行传送时，REQ64#不能又漂移。 ●ACK64#被目标有效以回应被主设备有效的REQ64#（如果目标支持64位数据传送），ACK64#与DEVSEL#具有相同的时序和间隔（但是直到REQ64#被主设备有效，ACK64#才可被有效）。像REQ64#一样，ACK64#信号线也必须由系统主板上的上拉电阻来支持。当32位设备是传送目标时，ACK64#不能漂移。 ●AD[64::32]包含上部4位地址／数据通道。 ●C/BE#[7::4]包含高4位命令/字节使能信号。 ●PAR64是为上部4个AD通道和上部4位C/BE信号线提供偶校验的奇偶校验位。 以下是几小结详细讨论64位数据传送和寻址功能。 3.在32位插入式连接器上的64位卡