搜档网
当前位置:搜档网 › PLC 外文文献+翻译

PLC 外文文献+翻译

PLC 外文文献+翻译
PLC 外文文献+翻译

Programmable logic controller

A programmable logic controller (PLC) or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or lighting fixtures. PLCs are used in many industries and machines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.

1.History

The PLC was invented in response to the needs of the American automotive manufacturing industry. Programmable logic controllers were initially adopted by the automotive industry where software revision replaced the re-wiring of hard-wired control panels when production models changed.

Before the PLC, control, sequencing, and safety interlock logic for manufacturing automobiles was accomplished using hundreds or thousands of relays, cam timers, and drum sequencers and dedicated closed-loop controllers. The process for updating such facilities for the yearly model change-over was very time consuming and expensive, as electricians needed to individually rewire each and every relay.

In 1968 GM Hydramatic (the automatic transmission division of General Motors) issued a request for proposal for an electronic replacement for hard-wired relay systems. The winning proposal came from Bedford Associates of Bedford, Massachusetts. The first PLC, designated the 084 because it was Bedford Associates' eighty-fourth project, was the result. Bedford Associates started a new company dedicated to developing, manufacturing, selling, and servicing this new product: Modicon, which stood for MOdular DIgital CONtroller. One of the people who worked on that project was Dick Morley, who is considered to be the "father" of the PLC. The Modicon brand was sold in 1977 to Gould Electronics, and later acquired by German Company AEG and then by French Schneider Electric, the current owner. One of the very first 084 models built is now on display at Modicon's headquarters in North Andover, Massachusetts. It was presented to Modicon by GM, when the unit was retired after nearly twenty years of uninterrupted service. Modicon used the 84

moniker at the end of its product range until the 984 made its appearance.

The automotive industry is still one of the largest users of PLCs.

2.Development

Early PLCs were designed to replace relay logic systems. These PLCs were programmed in "ladder logic", which strongly resembles a schematic diagram of relay logic. This program notation was chosen to reduce training demands for the existing technicians. Other early PLCs used a form of instruction list programming, based on a stack-based logic solver.

Modern PLCs can be programmed in a variety of ways, from ladder logic to more traditional programming languages such as BASIC and C. Another method is State Logic, a very high-level programming language designed to program PLCs based on state transition diagrams.

Many early PLCs did not have accompanying programming terminals that were capable of graphical representation of the logic, and so the logic was instead represented as a series of logic expressions in some version of Boolean format, similar to Boolean algebra. As programming terminals evolved, it became more common for ladder logic to be used, for the aforementioned reasons. Newer formats such as State Logic and Function Block (which is similar to the way logic is depicted when using digital integrated logic circuits) exist, but they are still not as popular as ladder logic.

A primary reason for this is that PLCs solve the logic in a predictable and repeating sequence, and ladder logic allows the programmer (the person writing the logic) to see any issues with the timing of the logic sequence more easily than would be possible in other formats.

2.1Programming

Early PLCs, up to the mid-1980s, were programmed using proprietary programming panels or special-purpose programming terminals, which often had dedicated function keys representing the various logical elements of PLC programs. Programs were stored on cassette tape cartridges. Facilities for printing and documentation were very minimal due to lack of memory capacity. The very oldest PLCs used non-volatile magnetic core memory.

More recently, PLCs are programmed using application software on personal computers. The computer is connected to the PLC through Ethernet, RS-232, RS-485 or RS-422 cabling. The programming software allows entry and editing of the ladder-style logic. Generally the software provides functions for debugging and

troubleshooting the PLC software, for example, by highlighting portions of the logic to show current status during operation or via simulation. The software will upload and download the PLC program, for backup and restoration purposes. In some models of programmable controller, the program is transferred from a personal computer to the PLC though a programming board which writes the program into a removable chip such as an EEPROM or EPROM.

3.Functionality

The functionality of the PLC has evolved over the years to include sequential relay control, motion control, process control, distributed control systems and networking. The data handling, storage, processing power and communication capabilities of some modern PLCs are approximately equivalent to desktop computers. PLC-like programming combined with remote I/O hardware, allow a general-purpose desktop computer to overlap some PLCs in certain applications. Regarding the practicality of these desktop computer based logic controllers, it is important to note that they have not been generally accepted in heavy industry because the desktop computers run on less stable operating systems than do PLCs, and because the desktop computer hardware is typically not designed to the same levels of tolerance to temperature, humidity, vibration, and longevity as the processors used in PLCs. In addition to the hardware limitations of desktop based logic, operating systems such as Windows do not lend themselves to deterministic logic execution, with the result that the logic may not always respond to changes in logic state or input status with the extreme consistency in timing as is expected from PLCs. Still, such desktop logic applications find use in less critical situations, such as laboratory automation and use in small facilities where the application is less demanding and critical, because they are generally much less expensive than PLCs.

In more recent years, small products called PLRs (programmable logic relays), and also by similar names, have become more common and accepted. These are very much like PLCs, and are used in light industry where only a few points of I/O (i.e. a few signals coming in from the real world and a few going out) are involved, and low cost is desired. These small devices are typically made in a common physical size and shape by several manufacturers, and branded by the makers of larger PLCs to fill out their low end product range. Popular names include PICO Controller, NANO PLC, and other names implying very small controllers. Most of these have between 8 and 12 digital inputs, 4 and 8 digital outputs, and up to 2 analog inputs. Size is usually

about 4" wide, 3" high, and 3" deep. Most such devices include a tiny postage stamp sized LCD screen for viewing simplified ladder logic (only a very small portion of the program being visible at a given time) and status of I/O points, and typically these screens are accompanied by a 4-way rocker push-button plus four more separate push-buttons, similar to the key buttons on a VCR remote control, and used to navigate and edit the logic. Most have a small plug for connecting via RS-232 or RS-485 to a personal computer so that programmers can use simple Windows applications for programming instead of being forced to use the tiny LCD and push-button set for this purpose. Unlike regular PLCs that are usually modular and greatly expandable, the PLRs are usually not modular or expandable, but their price can be two orders of magnitude less than a PLC and they still offer robust design and deterministic execution of the logic.

4.PLC Topics

4.1.Features

The main difference from other computers is that PLCs are armored for severe conditions (such as dust, moisture, heat, cold) and have the facility for extensive input/output (I/O) arrangements. These connect the PLC to sensors and actuators. PLCs read limit switches, analog process variables (such as temperature and pressure), and the positions of complex positioning systems. Some use machine vision. On the actuator side, PLCs operate electric motors, pneumatic or hydraulic cylinders, magnetic relays, solenoids, or analog outputs. The input/output arrangements may be built into a simple PLC, or the PLC may have external I/O modules attached to a computer network that plugs into the PLC.

4.2System scale

A small PLC will have a fixed number of connections built in for inputs and outputs. Typically, expansions are available if the base model has insufficient I/O.

Modular PLCs have a chassis (also called a rack) into which are placed modules with different functions. The processor and selection of I/O modules is customised for the particular application. Several racks can be administered by a single processor, and may have thousands of inputs and outputs. A special high speed serial I/O link is used so that racks can be distributed away from the processor, reducing the wiring costs for large plants.

4.3User interface

PLCs may need to interact with people for the purpose of configuration, alarm

reporting or everyday control.

A simple system may use buttons and lights to interact with the user. Text displays are available as well as graphical touch screens. More complex systems use a programming and monitoring software installed on a computer, with the PLC connected via a communication interface.

4.4Communications

PLCs have built in communications ports, usually 9-pin RS-232, but optionally EIA-485 or Ethernet. Modbus, BACnet or DF1 is usually included as one of the communications protocols. Other options include various fieldbuses such as DeviceNet or Profibus. Other communications protocols that may be used are listed in the List of automation protocols.

Most modern PLCs can communicate over a network to some other system, such as a computer running a SCADA (Supervisory Control And Data Acquisition) system or web browser.

PLCs used in larger I/O systems may have peer-to-peer (P2P) communication between processors. This allows separate parts of a complex process to have individual control while allowing the subsystems to co-ordinate over the communication link. These communication links are also often used for HMI devices such as keypads or PC-type workstations.

4.5Programming

PLC programs are typically written in a special application on a personal computer, then downloaded by a direct-connection cable or over a network to the PLC. The program is stored in the PLC either in battery-backed-up RAM or some other non-volatile flash memory. Often, a single PLC can be programmed to replace thousands of relays.

Under the IEC 61131-3 standard, PLCs can be programmed using standards-based programming languages. A graphical programming notation called Sequential Function Charts is available on certain programmable controllers. Initially most PLCs utilized Ladder Logic Diagram Programming, a model which emulated electromechanical control panel devices (such as the contact and coils of relays) which PLCs replaced. This model remains common today.

IEC 61131-3 currently defines five programming languages for programmable control systems: FBD (Function block diagram), LD (Ladder diagram), ST (Structured text, similar to the Pascal programming language), IL (Instruction list,

similar to assembly language) and SFC (Sequential function chart). These techniques emphasize logical organization of operations.

While the fundamental concepts of PLC programming are common to all manufacturers, differences in I/O addressing, memory organization and instruction sets mean that PLC programs are never perfectly interchangeable between different makers. Even within the same product line of a single manufacturer, different models may not be directly compatible.

5.PLC compared with other control systems

PLCs are well-adapted to a range of automation tasks. These are typically industrial processes in manufacturing where the cost of developing and maintaining the automation system is high relative to the total cost of the automation, and where changes to the system would be expected during its operational life. PLCs contain input and output devices compatible with industrial pilot devices and controls; little electrical design is required, and the design problem centers on expressing the desired sequence of operations. PLC applications are typically highly customized systems so the cost of a packaged PLC is low compared to the cost of a specific custom-built controller design. On the other hand, in the case of mass-produced goods, customized control systems are economic due to the lower cost of the components, which can be optimally chosen instead of a "generic" solution, and where the non-recurring engineering charges are spread over thousands or millions of units.

For high volume or very simple fixed automation tasks, different techniques are used. For example, a consumer dishwasher would be controlled by an electromechanical cam timer costing only a few dollars in production quantities.

A microcontroller-based design would be appropriate where hundreds or thousands of units will be produced and so the development cost (design of power supplies, input/output hardware and necessary testing and certification) can be spread over many sales, and where the end-user would not need to alter the control. Automotive applications are an example; millions of units are built each year, and very few end-users alter the programming of these controllers. However, some specialty vehicles such as transit busses economically use PLCs instead of custom-designed controls, because the volumes are low and the development cost would be uneconomic.

Very complex process control, such as used in the chemical industry, may require algorithms and performance beyond the capability of even high-performance PLCs. Very high-speed or precision controls may also require customized solutions; for

example, aircraft flight controls.

Programmable controllers are widely used in motion control, positioning control and torque control. Some manufacturers produce motion control units to be integrated with PLC so that G-code (involving a CNC machine) can be used to instruct machine movements.

PLCs may include logic for single-variable feedback analog control loop, a "proportional, integral, derivative" or "PID controller". A PID loop could be used to control the temperature of a manufacturing process, for example. Historically PLCs were usually configured with only a few analog control loops; where processes required hundreds or thousands of loops, a distributed control system (DCS) would instead be used. As PLCs have become more powerful, the boundary between DCS and PLC applications has become less distinct.

PLCs have similar functionality as Remote Terminal Units. An RTU, however, usually does not support control algorithms or control loops. As hardware rapidly becomes more powerful and cheaper, RTUs, PLCs and DCSs are increasingly beginning to overlap in responsibilities, and many vendors sell RTUs with PLC-like features and vice versa. The industry has standardized on the IEC 61131-3 functional block language for creating programs to run on RTUs and PLCs, although nearly all vendors also offer proprietary alternatives and associated development environments.

6.Digital and analog signals

Digital or discrete signals behave as binary switches, yielding simply an On or Off signal (1 or 0, True or False, respectively). Push buttons, limit switches, and photoelectric sensors are examples of devices providing a discrete signal. Discrete signals are sent using either voltage or current, where a specific range is designated as On and another as Off. For example, a PLC might use 24 V DC I/O, with values above 22 V DC representing On, values below 2VDC representing Off, and intermediate values undefined. Initially, PLCs had only discrete I/O.

Analog signals are like volume controls, with a range of values between zero and full-scale. These are typically interpreted as integer values (counts) by the PLC, with various ranges of accuracy depending on the device and the number of bits available to store the data. As PLCs typically use 16-bit signed binary processors, the integer values are limited between -32,768 and +32,767. Pressure, temperature, flow, and weight are often represented by analog signals. Analog signals can use voltage or current with a magnitude proportional to the value of the process signal. For example,

an analog 0 - 10 V input or 4-20 mA would be converted into an integer value of 0 - 32767.

外文翻译 外文文献 英文文献 胜任力模型研究

Research on Competency Model:A Literature Review and Empirical Studies Abstract Western countries have applied competency models to addressing problems existed in their administrative and managerial systems since 1970s,and the findings is positine and promising. However, competency model hasn’t been introduced to China until 1990s and it is still unknown and mysterious to many Chinese managers. This paper aims to uncover the mysterious veil of competency model in order to broaden the horizon of Chinese managers and boost China's human resource development as well as management. Keywords:Competency,Competency Models,Empirical Studies of Competency Models It has been more than 30 years since competency model was utilized to human resource management.In western countries,competency model first displayed its effectiveness in government administration, meanwhile many multinationals and their branch companies applied the competency model to their daily business management and their business was a great success. As the notion of competency is gradually come to light and accepted by people all around the world,more and more enterprises have been trying to build their own competency model under the help of professional consultant firms. As a result,competency model has gradually been a very fashionable phrase in the field of management and quite a few enterprises are thus benefited from it. In recent years, competency model has become a hot spot in the Chinese academia as well as big-,middle- and small-sized enterprises alike,many relevant writings and books have also been translated and published. However, competency and competency model are still mysterious to many Chinese scholars, business managers as well as government administrators. Purpose and Significance of the Study The purpose of the study aims to make a critical literature review of the competency model,clarify some confusion related to it and explore its application. The following questions are employed to guide this study:What is competency? What is competency model? What are the theoretical and empirical findings related to competency model? The study illustrates how we could take advantage of competency model in our harmonious society building. On one hand,the study will delineate competency and competency model in order to clarify confusions related to it since it is still strange and mysterious to many Chinese managers and administrators;on the other hand,the

PLC外文翻译

外文翻译 原文:The open system merit of Computer Numerical Control The open system merit is the system simple, the cost low, but the shortcoming is the precision is low. The reverse gap, the guide screw pitch error, stop inferiorly can affect the pointing accuracy by mistake. Following several kind of improvements measure may cause the pointing accuracy distinct improvement. 1. reverse gap error compensates The numerical control engine bed processing cutting tool and the work piece relative motion is depends upon the drive impetus gear,the guide screw rotation, thus the impetus work floor and so on moves the part to produce moves realizes. As traditional part gear, guide screw although the manufacture precision is very high, but always unavoidably has the gap. As a result of this kind of gap existence, when movement direction change, starts the section time to be able to cause inevitably actuates the part wasting time, appears the instruction pulse to push the motionless functional element the aspect. This has affected the engine bed processing precision, namely the instruction pulse and actual enters for the step does not tally,has the processing error therefore, the split-ring numerical control system all establishes generally has the reverse gap error compensatory function, with by makes up which wastes time the step reverse gap difference compensates is first actual reverse enters for the error, converts the pulse equivalent number it, compensates the subroutine as the gap the output, when the computer judgment appears when instruction for counter motion, transfers the gap to compensate the subroutine immediately, compensates the pulse after the output to eliminate the reverse gap to carry on again normally inserts makes up the movement. 2. often the value systematic characteristic position error compensates A kind of storehouse by transfers for the designer. Like this in the components design stage, the designer only must input the characteristic the parameter, the system direct production characteristic example model: We must save the related characteristic class in the database the structure information, the database table collection are use in saving this part of related information. According to the characteristic type definition need, we defined the characteristic class code table, the

PLC外文文献翻译

Programmable logic controller A programmable logic controller (PLC) or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or lighting fixtures. PLCs are used in many industries and machines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result. 1.History The PLC was invented in response to the needs of the American automotive manufacturing industry. Programmable logic controllers were initially adopted by the automotive industry where software revision replaced the re-wiring of hard-wired control panels when production models changed. Before the PLC, control, sequencing, and safety interlock logic for manufacturing automobiles was accomplished using hundreds or thousands of relays, cam timers, and drum sequencers and dedicated closed-loop controllers. The process for updating such facilities for the yearly model change-over was very time consuming and expensive, as electricians needed to individually rewire each and every relay. In 1968 GM Hydramatic (the automatic transmission division of General Motors) issued a request for proposal for an electronic replacement for hard-wired relay systems. The winning proposal came from Bedford Associates of Bedford, Massachusetts. The first PLC, designated the 084 because it was Bedford Associates' eighty-fourth project, was the result. Bedford Associates started a new company dedicated to developing, manufacturing, selling, and servicing this new product: Modicon, which stood for MOdular DIgital CONtroller. One of the people who worked on that project was Dick Morley, who is considered to be the "father" of the PLC. The Modicon brand was sold in 1977 to Gould Electronics, and later acquired by German Company AEG and then by French Schneider Electric, the current owner. One of the very first 084 models built is now on display at Modicon's headquarters in North Andover, Massachusetts. It was presented to Modicon by GM, when the unit was retired after nearly twenty years of uninterrupted service. Modicon used the 84

论文外文文献翻译3000字左右

南京航空航天大学金城学院 毕业设计(论文)外文文献翻译 系部经济系 专业国际经济与贸易 学生姓名陈雅琼学号2011051115 指导教师邓晶职称副教授 2015年5月

Economic policy,tourism trade and productive diversification (Excerpt) Iza Lejárraga,Peter Walkenhorst The broad lesson that can be inferred from the analysis is that promoting tourism linkages with the productive capabilities of a host country is a multi-faceted approach influenced by a variety of country conditions.Among these,fixed or semi-fixed factors of production,such as land,labor,or capital,seem to have a relatively minor influence.Within the domain of natural endowments,only agricultural capital emerged as significant.This is a result that corresponds to expectations,given that foods and beverages are the primary source of demand in the tourism economy.Hence,investments in agricultural technology may foment linkages with the tourism market.It is also worth mentioning that for significant backward linkages to emerge with local agriculture,a larger scale of tourism may be important. According to the regression results,a strong tourism–agriculture nexus will not necessarily develop at a small scale of tourism demand. It appears that variables related to the entrepreneurial capital of the host economy are of notable explanatory significance.The human development index(HDI), which is used to measure a country's general level of development,is significantly and positively associated with tourism linkages.One plausible explanation for this is that international tourists,who often originate in high-income countries,may feel more comfortable and thus be inclined to consume more in a host country that has a life-style to which they can relate easily.Moreover,it is important to remember that the HDI also captures the relative achievements of countries in the level of health and education of the population.Therefore,a higher HDI reflects a healthier and more educated workforce,and thus,the quality of local entrepreneurship.Related to this point,it is important to underscore that the level of participation of women in the host economy also has a significantly positive effect on linkages.In sum, enhancing local entrepreneurial capital may expand the linkages between tourism and other sectors of the host country.

英语学术论文写作实践作业

英语学术论文写作实践作业 作者 系(院)外国语学院 专业英语 年级2xxx级 学号 写作意向 旅游的快速发展以及随着中国融入全球化经济,中国与世界各国的交流不断增多,例如,加入WTO、2008年北京成功举办奥运会及上海世博会等,这些显示了中国在国际舞台上扮演越来越重要的角色。近些年来,越来越多的国家希望了解中国,许多外国朋友纷至沓来。特别是中国旅游风景名胜区,每年接待的外国游客越来越多。为了方便外国友人,我国旅游景区就必须提供英语景点导游词。旅游景点导游词主要指的是旅游景区公开和面对旅游者的告示、指示、提示、警示、标示等文字及图形信息,涉及到食、宿、行、游、娱、购等日常生活的方方面面。在旅游景区内,游客最为集中,与旅游宣传册、地图、宣传单等相比,景点导游词更加引人注目集中,更加直截了当地发挥其信息指示功能。由于旅游景点导游词需要及时满足的是社会公众和旅游者的直接社会、行为和心理需求,也反映了生活在这个社会群体的整体文化素质、道德修养和精神面貌,是一个国家对外交流水平和人文环境的具体体现。因此其翻译质量将会响到游客的旅游线路、兴致、感受及印象,进而间接影响我国旅游业的发展。因此,对旅游景点导游词的特点、翻译策略进行探讨具有一定的现实意义。 资料的初步整理 对于英语景点导游词,许多中外学者都做出自己的研究,提出自己的观点。以下是中外学术界的众多研究和观点。 蔡媛媛(2007)《英语景点导游词的语言特点》一文中指出,英语景点导游词具有相应的功能特点。(1)指示性。指示性景点导游词主要是提供给公众一些信息服务,没有任何限制或强制在内,同时也不强制要求公众采取任何行动,其功能只是指示服务内容。因此,指示性景点导游词也被称为指导性或引导性景点导游词。这也是景点导游词最基本、最主要的功能。例如:One Way (单行线)、Tickets (售票处)、Department Store (百货商场)。(2)提示性。提示性景点导游词提示性景点导游词提醒公众注意某些事情,同时提示性景点导游词也并不针对特殊或个别人群。这类景点导游词应用非常广泛,通过提示性景点导游词可以了解什么该做什么不该做,但是这种提示性景点导游词并不具有强制性,公众可根据实际情况来选择执行或不执行。例如:Caution!Radiation(当心射线)、Watch Your Hand(当心夹手)、Don’t Touch(请勿手扶)。(3)限制性。限制性景点导游词对有关公众提出限制或约束的要求,希望有关公众为了大众的利益遵守一定的规则。多数情况下限制性景点导游词语气较为直接,一目了然,但不会让人感到强硬、粗暴或无理。例如:Athletes Only (运动员专用通道)、Large Vehicles Keep Right (大型车靠右)。(4)强制性。强制性景点导游词对有关公众有较大约束力,要求有关公众必须或不得采取任何行动或严格遵守规则。这类景点导游词的语言直接、强制,没有任何商量的余地。例如:No Parking (禁止停车)。 上面是学者对景点导游词特点的研究,对于翻译,颜莉(2008)《英语景点导游词的文体特点及汉英翻译》一文中说到,在进行景点导游词的汉英翻译前,应先了解英语景点导游词的文体特点,这样才能更加准确地将汉语景点导游词译为地道的英语表达方式。代博君(2010)在《景点导游词的语言特征及翻译策略》一文中指出,景点导游词的翻译应属于实用翻译,也称语用翻译。法国翻译理论家Jean Delisle 将语用翻译界定为:运用语用学知识对语用文

外文文献翻译助手

五分钟搞定5000字-外文文献翻译 在科研过程中阅读翻译外文文献是一个非常重要的环节,许多领域高水平的文献都是外文文献,借鉴一些外文文献翻译的经验是非常必要的。由于特殊原因我翻译外文文献的机会比较多,慢慢地就发现了外文文献翻译过程中的三大利器:Google“翻译”频道、金山词霸(完整版本)和CNKI“翻译助手"。 具体操作过程如下: 1.先打开金山词霸自动取词功能,然后阅读文献; 2.遇到无法理解的长句时,可以交给Google处理,处理后的结果猛一看,不堪入目,可是经过大脑的再处理后句子的意思基本就明了了; 3.如果通过Google仍然无法理解,感觉就是不同,那肯定是对其中某个“常用单词”理解有误,因为某些单词看似很简单,但是在文献中有特殊的意思,这时就可以通过CNKI的“翻译助手”来查询相关单词的意思,由于CNKI的单词意思都是来源与大量的文献,所以它的吻合率很高。 另外,在翻译过程中最好以“段落”或者“长句”作为翻译的基本单位,这样才不会造成“只见树木,不见森林”的误导。 注: 1、Google翻译:https://www.sodocs.net/doc/9c13703473.html,/language_tools google,众所周知,谷歌里面的英文文献和资料还算是比较详实的。我利用它是这样的。一方面可以用它查询英文论文,当然这方面的帖子很多,大家可以搜索,在此不赘述。回到我自己说的翻译上来。下面给大家举个例子来说明如何用吧 比如说“电磁感应透明效应”这个词汇你不知道他怎么翻译, 首先你可以在CNKI里查中文的,根据它们的关键词中英文对照来做,一般比较准确。

在此主要是说在google里怎么知道这个翻译意思。大家应该都有词典吧,按中国人的办法,把一个一个词分着查出来,敲到google里,你的这种翻译一般不太准,当然你需要验证是否准确了,这下看着吧,把你的那支离破碎的翻译在google里搜索,你能看到许多相关的文献或资料,大家都不是笨蛋,看看,也就能找到最精确的翻译了,纯西式的!我就是这么用的。 2、CNKI翻译:https://www.sodocs.net/doc/9c13703473.html, CNKI翻译助手,这个网站不需要介绍太多,可能有些人也知道的。主要说说它的有点,你进去看看就能发现:搜索的肯定是专业词汇,而且它翻译结果下面有文章与之对应(因为它是CNKI检索提供的,它的翻译是从文献里抽出来的),很实用的一个网站。估计别的写文章的人不是傻子吧,它们的东西我们可以直接拿来用,当然省事了。网址告诉大家,有兴趣的进去看看,你们就会发现其乐无穷!还是很值得用的。https://www.sodocs.net/doc/9c13703473.html, 3、网路版金山词霸(不到1M):https://www.sodocs.net/doc/9c13703473.html,/6946901637944806 翻译时的速度: 这里我谈的是电子版和打印版的翻译速度,按个人翻译速度看,打印版的快些,因为看电子版本一是费眼睛,二是如果我们用电脑,可能还经常时不时玩点游戏,或者整点别的,导致最终SPPEED变慢,再之电脑上一些词典(金山词霸等)在专业翻译方面也不是特别好,所以翻译效果不佳。在此本人建议大家购买清华大学编写的好像是国防工业出版社的那本《英汉科学技术词典》,基本上挺好用。再加上网站如:google CNKI翻译助手,这样我们的翻译速度会提高不少。 具体翻译时的一些技巧(主要是写论文和看论文方面) 大家大概都应预先清楚明白自己专业方向的国内牛人,在这里我强烈建议大家仔

第三方物流外文文献(原文与翻译)

我国第三方物流中存在的问题、原因及战略选择 熊卫 【摘要】我国物流业发展刚刚起步,第三方物流的理论和实践等方面都比较薄弱。本文指出我国第三方物流存在的问题在于国内外第三方物流企业差距、物流效率不高、缺乏系统性管理、物流平台构筑滞后、物流管理观念落后等。分析了产生上述问题的原因,并提出了精益物流、中小型第三方物流企业价值链联盟、大型第三方物流企业虚拟化战略等三种可供选择的第三方物流企业发展战略。 【关键词】第三方物流;精益物流战略;价值链联盟;虚拟化战略 1引言 长期以来,我国国内企业对采购、运输、仓储、代理、包装、加工、配送等环节控制能力不强,在“采购黑洞”、“物流陷井”中造成的损失浪费难以计算。因此,对第三方物流的研究,对于促进我国经济整体效益的提高有着非常重要的理论和实践意义。本文试图对我国策三方物流存在的问题及原因进行分析探讨,并提出第三方物流几种可行的战略选择。 2我国第三方物流业存在的主要问题 (一)我国策三方物流企业与国外第三方物流企业的差距较大,具体表现在以下几个方面: 1、规模经济及资本差距明显。由于国外的大型第三方物流企业从全球经营的战略出发,其规模和资本优势是毫无疑问的,尤其初创时期的我国策三方物流业,本身的规模就很小,国外巨头雄厚的资本令国内企业相形见绌。 2、我国策三方物流业企业提供的物流服务水准及质量控制远不如国外同行。当国内一些企业还在把物流理解成“卡车加仓库“的时候,国外的物流企业早已完成了一系列标准化的改造。同时,国外的物流组织能力非常强大,例如德国一家第三方物流公司,公司各方面的物流专家遍布欧洲各地。如果有客户的货物需要经达不同的国家,那么欧洲各地的这些专家就在网上设计出一个最佳的物流解决方案。这种提供解决方案的能力就是这第三方物流公司的核心能力,而不像国内公司号称拥有多少条船,多少辆车。 3、我国加入WTO后物流产业的门槛降低。在物流服务业方面:我国承诺所有的服务行业,在经过合理过渡期后,取消大部分外国股权限制,不限制外国服务供应商进入

基于PLC相关的毕业设计外文翻译(可编辑修改word版)

毕业论文(设计)外文翻译 题目:可编程逻辑控制器技术 系部名称:信息工程系专业班级: 学生姓名:学号: 指导教师:教师职称: 2014 年3 月XX 日

译文 可编程逻辑控制器技术 引言 PLC(可编程逻辑控制器)实际是一个工业控制系统(近来我们看到更多的是用处理器来取代微控制器),在软件和硬件都配备的条件下,适合应用于工业环境。PLC 的发明是相当必要的,它代替了传统的依靠由继电接触器电路来控制电机。PLC 的工作原理是根据它的输入信号和工作状态来确定输出。用户通常是通过软件或编程输入一个程序,来输出所需要的结果。 如图 8-1 所示,PLC 是由典型的黑色构件组成。特别需要注意的是它的输入和输出, 因为在这些模块上,工业环境会给 CPU 一个输入线,所以很有必要将 CPU 模块隔离以保护其免遭有害的影响。程序单元通常是用计算机来编写程序(一般是梯形图)。 1.1CPU 的中央处理单元 中央处理单元(CPU)是一个 PLC 的主控制器。一般 CPU 本身是一个微控制器。通常这些都是 8 位微控制器,如 8051 ,现在的这些是 16 位和 32 位微控制器。潜规则是,你会发现用在 PLC 控制器上的微控制器多数是由日本生产的日立和富士通,欧洲的西门子控制器,和美国的摩托罗拉微控制器。CPU 也负责通讯,与 PLC 控制器的其它部分相互联系,如程序执行,内存操作,监督输入和设置输出。PLC 控制器拥有复杂的程序用于内存检查,以确保 PLC 内存不被损坏(内存检查是为了安全原因而作出的)。一般来说,CPU 单元多数用来检查 PLC 控制器本身,所以有可能出现的错误很早就会被发现。你可以简单地看任何 PLC 控制器,查看错误信号在发光二极管上的种种指示形式。 1.2内存 系统内存(今天主要是在 FLASH 技术上实现)用于一台 PLC 的过程控制系统。除了 这个操作系统它还包含用户程序将梯形图翻译成二进制的形式。 FLASH 存储器的内容仅在 用户程序改变下可以改变。PLC 控制器较早被用来代替闪存,EPROM 存储器代替了那些只能依靠紫外线灯等擦除内存并依靠程序员来编程的 FLASH 存储器。在 FLASH 技术的作用下这个过程被大大的缩短了。重组程序内存通过程序中的串行通讯用于应用程序开发。使用内存被划分成多个具有特殊功能的模块。存储器某些部分用来存储输入状态和输出状态。一个 输入信号的实际状态是用 1 或0 存储在一个特定的存储位。每一个输入信号和输出信号在内存里都有一个位与之相对应。内存的其他部分用来存储用户程序中使用的变量以及变量的内容。例如,定时器的值和计数器的值都将被存储在这部分内存里。 1.3PLC 控制器的编程 PLC 控制器可以通过计算机(常用的方式)进行编程,还可以通过手动编程器(控制台)编程。这实际上意味着如果你有需要的编程软件那么每个 PLC 控制器都可以通过计算机进行编程。今天的传输计算机是非常适合在工厂对 PLC 控制器进行编程的。这对工业有着非常重要的意义。一旦系统被刷新,重新读取正确的程序到 PLC 就很重要。还可以定期检查 PLC 中的程序是否改变了。这有助于避免在工厂车间发生危险状况(部分汽车制造商建立了通信网络,定期检查项目中的 PLC 控制器,以确保执行的程序是正确的)。

毕业论文外文文献翻译Android平台上的社交应用和游戏应用来比较学习软件体系结构

毕业设计(论文)外文文献翻译 文献、资料中文题目:通过开发Android平台上的社交应 用和游戏应用来比较学习软件体系结构 文献、资料英文题目: 文献、资料来源: 文献、资料发表(出版)日期: 院(部): 专业: 班级: 姓名: 学号: 指导教师: 翻译日期: 2017.02.14

通过开发Android平台上的社交应用和游戏应用来比较学习软件体系结构 1.引言 电脑游戏和视频游戏非常受儿童和青少年的欢迎,在年轻人的文化发挥了突出的作用[1]。现在游戏可以在技术丰富的配备了笔记本电脑,智能手机,游戏机(移动和固定),机顶盒,和其他数字设备的环境中运行。从这一现象,人们相信将年轻人对游戏的内在动机与教育内容和目标结合就会变成Prensky称之为“以数字游戏为基础的学习”的学习方法[2]。 青年学生生活的游戏中除了丰富的外观,游戏开发技术已经成熟,并且越来越先进[3]。基于现有的各种游戏开发环境,游戏开发过程中的全部责任可以分为几个的专家领域和角色,如游戏程序员,3D模型的创造者,游戏设计师,音乐家,漫画家,剧作家,等等。游戏内容与技术相结合的过程可以通过游戏引擎和使用网络上的各种用户和专家社区的可用信息得到简化。例如,微软的XNA 游戏开发工具包提供的游戏循环函数绘制及更新游戏内容,而且还提供了方便的游戏开发组件来加载不同格式的图形,音频和视频。这使得游戏迷们如无论有没有编程背景的学生修改现有的游戏或开发新游戏。他们可以用这些游戏创作工具实现自己的游戏概念设计,学习发展技能和相关知识,积累相关的实际经验。 在这种情况下,不但游戏可以用于学习而且通过激发任务机制,游戏开发工具可以用来研究计算机科学(CS),软件工程(SE),和游戏编程相关主题。一般来说,游戏可以用三种方式集成在教育中[4,5]。首先,游戏可以用来代替传统的练习,鼓励学生把额外的努力用来做练习,给老师或助教一个实时地监控学生是如何练习的机会[6,7]。第二,游戏可以作为一个讲座的一部分来促进学生的参与,增加学生的动力[8,9]。第三,将要求学生们修改或开发游戏作为使用游戏开发框架(GDF)学习CS和SE方面技能的课程的一部分。我们把后者的学习方法为以游戏开发为基础的学习(GDBL)。GDF表示可以用来开发或修改游戏,例如,该工具包的游戏引擎,游戏编辑器,或游戏(模拟)平台,甚至任何集成开发环境(IDE),如Visual C + +,Eclipse和Android SDK,J2ME,因为所有的人都可以用来开发游戏。 本文重点研究学生通过在Android平台开发游戏应用学习软件体系结构和在Android平台开发社交应用(例如,天气预报,聊天软件)学习软件体系结构的相似点和不同点。将游戏开发放到CS或者SE课程中的动机是利用学生对游戏及游戏开发的迷恋来激发他们通过该项目更多更好的学习课程材料。

外文文献翻译——参考格式

广东工业大学华立学院 本科毕业设计(论文) 外文参考文献译文及原文 系部经济学部 专业经济学 年级 2007级 班级名称 07经济学6班 学号 16020706001 学生姓名张瑜琴 指导教师陈锶 2011 年05月

目录 1挑战:小额贷款中的进入和商业银行的长期承诺 (1) 2什么商业银行带给小额贷款和什么把他们留在外 (2) 3 商业银行的四个模型进入小额贷款之内 (4) 3.1内在的单位 (4) 3.2财务子公司 (5) 3.3策略的同盟 (5) 3.4服务公司模型 (6) 4 合法的形式和操作的结构比较 (8) 5 服务的个案研究公司模型:厄瓜多尔和Haiti5 (9)

1 挑战:小额贷款中的进入和商业银行的长期承诺 商业银行已经是逐渐重要的运动员在拉丁美洲中的小额贷款服务的发展2到小额贷款市场是小额贷款的好消息客户因为银行能提供他们一完整类型的财务的服务,包括信用,储蓄和以费用为基础的服务。整体而言,它也对小额贷款重要,因为与他们广泛的身体、财务的和人类。如果商业银行变成重的运动员在小额贷款,他们能提供非常强烈的竞争到传统的小额贷款机构。资源,银行能廉宜地发射而且扩张小额贷款服务rela tively。如果商业广告银行在小额贷款中成为严重的运动员,他们能提出非常强烈的竞争给传统的小额贷款机构。然而,小额贷款社区里面有知觉哪一商业银行进入进入小额贷款将会是短命或浅的。举例来说,有知觉哪一商业银行首先可能不搬进小额贷款因为时候建立小额贷款操作到一个有利润的水平超过银行的标准投资时间地平线。或,在进入小额贷款,银行之后可能移动在-上面藉由增加贷款数量销售取利润最大值-或者更坏的事,退出如果他们是不满意与小额贷款的收益性的水平。这些知觉已经被特性加燃料商业银行的情形进入小额贷款和后来的出口之内。在最极端的,一些开业者已经甚至宣布,”降低尺度死!”而且抛弃了与主意合作的商业银行。 在最 signific 看得到的地方,蚂蚁利益商业银行可能带给小额贷款,国际的ACCION 发展发射而且扩张的和一些商业银行的关系小额贷款操作。在这些情形的大部分方面, ACCION 和它的合伙人正在使用方法,已知的当做服务公司模型,表演早答应当做一个能工作的方法克服真正的。 商业银行的障碍进入和穿越建立长命的小额贷款操作一个商业银行 这论文描述如何服务公司模型、住址商业银行中的主要议题进入进小额贷款,监定成功建立的因素动作井小额贷款服务公司,和礼物结果和小额贷款的课servic e 公司用最长的经验,在海地和审判官席 del 的 SOGEBANK│ SOGESOL 初期结果指出那这服务公司模型表现一重要的突破在促成商业银行进入和留在小额贷款。在厄瓜多尔的 Pichincha│ CREDIFE。初期结果指出服务公司模型在促成商业广告中表现一次重要的突破银行进入而且留在小额贷款。

plc外文翻译

1 Bit Logic In structi ons 1.1 Overview of Bit Logic In structi ons 1.1.1 Description Bit logic in structi ons work with two digits, 1 and 0. These two digits form the base of a nu mber system called the binary system. The two digits 1 and 0 are called binary digits or bits. In the world of con tacts and coils, a 1 in dicates activated or en ergized, and a 0 in dicates not activated or not en ergized. The bit logic in struct ions in terpret sig nal states of 1 and 0 and comb ine them accord ing to Boolea n logic. These comb in ati ons produce a result of 1 or 0 that is called the “result of logic operati on ” (RLO). The logic operations that are triggered by the bit logic instructions perform a variety of fun cti ons. There are bit logic in structio ns to perform the followi ng fun cti ons: ---| |--- Normally Ope n Co ntact (Address) ---| / |--- Normally Closed Con tact (Address) ---(SAVE) Save RLO into BR Memory XOR Bit Exclusive OR ---()Output Coil ---(# )--- Midli ne Output ---|NOT|--- In vert Power Flow The followi ng in structio ns react to an RLO of 1: ---(S ) Set Coil ---(R ) Reset Coil SR Set-Reset Flip Flop RS Reset-Set Flip Flop Other in structi ons react to a positive or n egative edge tran siti on to perform the followi ng functions: ---(N)--- Negative RLO Edge Detectio n ---(P)--- Positive RLO Edge Detectio n NEG Address Negative Edge Detectio n POS Address Positive Edge Detectio n

相关主题