信息时代的机械工程学外文文献翻译、中英文翻译、外文翻译

外文翻译 信息时代的机械工程学 早在 20 世纪 80 年代，工程师认为需要进行大量实验因为缩短的产品开发循环促使工程师使用有效的技术。开发一种用于新产品中的革命性技术是冒险且易于失败的，采取短的进程对产品开发来讲是安全且更易成功的途径。 短的产品开发循环在工程领域也是有利的，这个领域里，资本和劳动力都是整体的。可以设计并制造不同产品的人在世界的任何地方都能够找到，但有新思想的人就很难找到了。地理上的距离已经不再是那些想在 6 个月内将发明付诸于实践的人的障碍了，如果你已经获得短的开发循环，只要你保持领先形势就不会是灾 难性的，但如果你已经处于六年的开发的过程并且竞争者已经赶上你，那么这个项目就处于更严峻的麻烦中。 工程师们在解决任何问题时都需要进行新的设计这种观念很快就过事了。在现代设计中的第一步是浏览英特网或者其他信息系统，看其他人是否设计了一种类似于你所需要的产品，诸如传动装置或者换热器等。通过这些信息系统，你可能发现有些人已经有了制造图纸，数控纸带和制造你的产品所需要的其他所有东西。这样，工程师们就可以把他们的职业技能集中在尚未解决的问题上。 在解决这类问题时，利用工作站和进入信息高速公路可以大大增强工程小组的能力 和效率。这些信息时代的工具可使工程小组利用大规模的数据库。数据库中有材料性能、标准、技术和成功的设计方案等信息。这些经过验证的设计可以通过下载直接应用，或者通过对其进行快速、简单的改进来满足特定的要求。将产品的技术要求通过网络送出去的远程制造也是可行的。你可以建立一个没有任何加工设备的虚拟公司，可以指示制造商，在产品加工往常后，将其直接送给你的客户。定期访问你的客户可以保证你设计的产品按照设计要求进行工作。尽管这些研制开发方式不可能对每个公司都完全适用，但是这种可能性是存在的。 传统设计通常用于小公司，大公 司嘲讽这种做法，他们讨厌处理服务市场成为少量主顾解决问题的思想：“这是我的产品”。一家大公司的人会说：“这是我能做的最好的产品了，你一定会喜欢它的，但如果你不喜欢的话。这条街下边有一家更小的公司可以解决你的问题。” 当今，几乎每家市场都是服务市场，因为顾客是有选择性的。如果你忽视了修改产品来满足顾客要求的潜在可能性。你将失去市场的主要部分甚至全部，尽管这些服务市场是临时的，但你的公司需要以一定的时间尽快答复他们所需要的。 瞄准机会的市场和根据客户要求尽心干涉机这种现象的出现，改变了工程师们进行研究工作的方式 。今天，研究工作通常是针对解决特定问题进行的。许多由政府资助或者由大公司出资开发的技术可以在非常低成本下被自由使用，尽管这种情况可能是暂时的。在对这些技术进行适当改进后，它们通常能够被直接用于产品开发，这使得许多公司可以节省昂贵的研究经费。在主要的技术障碍被克服后，研究工作应该主要致力于产品的商品化方面，而不是开发新的，有趣的，不确定的替换产品。 当涉及远景的时候，采用上述观点看问题，工程研究应该致力于消除将已知技术快速商品化的障碍。工作的重点是产品的自量和可靠性，这些在当今的顾客的头脑中是最重要的。很明显 ，一个自量差的声誉是一个不好的企业的同义词。企业应该尽最大努力来保证顾客得到合格的产品，这个努力包括在生产线的终端对产品进行严格的检验和自动更换有缺陷的产品。 研究必须考虑到可靠性等因素的成本利益 当可靠性提高时，制造成本和次同的最终成本内将会降低。如果在生产线的终端生产 30%的废品，这不仅会浪费金钱，也会给你的竞争对手创造一个利用你的想法制造产品，而且也为竞争者提供了采用你的设计卖给顾客的机会。 提高可靠性并且降低成本这个过程的关键是深入、广泛地利用设计软件。设计软件可以使工程师们加快每个阶段的设计工作。然 而，仅仅缩短每个阶段的设计时间，可能不会显著的缩短整个设计过程的时间。因而，必须致力于采用并行工程软件，这样可以使所设计组的成员都能使用共同的数据库。 随着我们更加完全的进入信息时代，成功需要工程师掌握一些有关发明和技术管理的独特知识和经验。 成功的工程师们不但应该具有宽广的知识和技能，而且还应该是某些关键技术或学科的专家，他们还应该在社会因素对市场的影响方面有敏锐的洞察能力。将来，花在解决日常工程问题上的花费将会减少，工程师们将会在一些更富有挑战，更亟待解决的问题上协同工作，大大缩短解决这些问题所需要的时 间。我们已经开始了工程实践的新阶段。计算机和网络使工程师们具有越来越强的解决问题的能力，这也给他们的工作带来很大的希望和喜悦。为了确保成功，我们使用的工具的性能和对更好的产品与系统的不断要求，应该与标志着在工程方面所有巨大努力的创新工作所带来的喜悦相适应。机械工程是一个伟大的行业，在我们尽可能多地利用了信息时代所提供的机遇后，它将变得更加美好。 微处理器系统可以在许多复杂程度不同的层次上进行描述。最简单复杂形式是描述不同功能上调解信息的相互作用和流动的简单的素描简图并且会用于测试微处理系统的操作。 所有微机 系统包含一个中央处理单元（ CPU）、程序和数据存储器以及输入、输出（ I/O）设备。 存储部分包含了用作程序存储器的掉电不易失信息的只读存储器（ ROM）和用作读 /写的掉电易失的随机访问数据存储器（ RAM），每种存储器都有许多不同类型的元件，如可写的 ROM 以及静态或动态的 RAM，应用时根据价格、功能来选择应用的。 微处理器的模拟输入路线是由模拟数字转化器提供的，并且可用于连接，如模拟感应元件的装置，模拟输出路线是又数字模拟转化器提供的并且可用于控制，像电动机一样的输出换能器，平行 I/O 装置提供了大量单独的路线。 在输出模型中这些可以编成程序来提供逻辑符 1 或 0 采用激活电平装置，例如灯在输入模型中允许微处理器度曲转变状况和其他电平装置，串行的 I/O 装置用来提供。同其他微处理系统或用于不同操作模型的成型系统中的操作控制台的对话。微处理系统的接口信号的等级和能量规格通常和与之接口的装置的信号规格不相匹配，例如 D/A 转换器所输出电压一般在 0-5V 范围内，反能提高小伏安电流，而电机需要在范围（ -12V-12V）控制电压最大电流安培。因此，附加的模拟接口电路系统通常有必要发挥功能，例如信号平转化扩大和过滤。 所有这些装置都通过系 统总线与 CPU 连接，用一种系统母线的方法。系统母线本身由地址母线，数据母线和控制母线组成的。实际上，母线是两个或多个装置间平行线的简单连接。每条母线中包括的线条数是根据用于系统中的微处理器类型和母线功能决定的。我们假设地址母线有十六条线，数据母线有八条线，控制母线包括 CPU 提供的控制功能而定的一定数量的线路。 地址和数据是运行计算机储存的程序、形成所有微处理器和计算机特征的基础。存储器由许多能由 CPU 通过数据总线写如数据的存储单元构成。每个存储单元具体位置由 CPU 用地址来唯一标识。为了从存储器或 I/O 设备中 写或读信息， CPU控制着地址和控制总线， CPU 希望将二进制信息写入地址的存储单元， CPU 首先将该地址送到地址总线上，然后作为数据送到数据总线上，控制总线中的控制线激活，启动数据写入适当的存储单元。相类似的情况用于 CPU 只读存储单元的地址送到地址的过程，这时数据流不是从存储器到 CPU，那么在 CPU 将要求的存储单元的地址送到地址总线上后， CPU 通过启动控制总线相关的控制线，指示存储器要读数据，存储器则做出反应，将该存储单元的内容当作数据，送上数据总线，然后 CPU读取到该数据。 在系统总线中，地址总线对 CPU 来 说是输出总线，但对其他设备是输入总线，控制总线包含许多线或者是 CPU 输出控制线，或者是输入控制线。数据总线既当作输入总线，又作输出总线，这要看 CPU 是读还是写数据，系统中所有元件都通过数据总线连接在一起，这意味着，最低限度上存储器和 I/O 设备的输出是连在一起的。例如感实际情况就是这样，则将引起所有连接的元件中几个或全部元件破坏，因为一些元件将试图驱动总线到逻辑 1 状态，而其他一些则试图驱动其为逻辑 0 状态。为了避免这个问题，连接到每个元件的数据总线有第三种状态即高阻态，在这种状态下元件对总线不再有负载的影响，这 就使连接到数据总线上的其他元件在需要时能将数据送上数据总线，这也就意味着在某一时刻仅有一个元件与数据总线相通。一个元件处于数据总线的逻辑 1、逻辑 0 或处于有关于数据母线的高电阻条件下的能力被称为 tristate 条件。这是共享相同的数据总线的设备重要的特性。 数据总线为 8 根因此能得到的单个数据被 8 位二进制数所限制，八位指一个字节，能代表从 0 到 255 的十进制；同样地，地址总线包含 16 根线，能代表的地址范围从 0 到 216-1 或 65535，这个数字常常被缩写成与二进制等价的十进制数，表示成 16K， 1K 在二进制系统中等于 1024，对于 CPU 而言，系统就像一连串的 64K的连续的存储单元，每个单元可存放 8 位二进制数。 CPU 包含许多寄存器，它们用语处理数据和地址，在所选择的例子中，这些数据寄存器为 8 位的寄存器，所有的数据操作都上都是 8 位，因此 CPU 就指 8 位CPU，但是支持地址操作的寄存器需 16 位，因为地址总线是 16 位的。地址总线的宽度与数据总线的宽度是独立的，因此 16 位或 32 位 CPU 典型的有 16 位， 24 位或32 位地址总线。 通常对微处理操作时用十六进制（基于 16）值代表二进制数，因为一个十六进制数与四位连续的二进制数相对应。 十六进制数比相等的二进制数量易读学，并且只需简单的换算就能将十六进制数与二进制数互译，十六进制数在文本中是用前缀 OX 标识，这是在 C 变成语言中所采用的。 硬件设计者没有必要使用整个 CPU 的地址空间，所要求的存储器可以在 CPU地址空间的任何地方执行，另外 I/O 装置可以成型，并且可以提供地址，通过这个地址 CPU 可以读取和记录进出系统的数据。这些存储器是以普通存储点出现于CPU。并占据地址空间的位置。地址空间中存储排雷和 I/O 地址通过系统存储图描述。 存储图是为了满足设计应用的要求，并且被硬件设计者用来分割 空间以便 使系统中存储设备的地址范围与存储映象图详细列出的地址相一致 ，所以系统中存储装置的地址域相当于存储图中的地址域。其可以作为输入通过地址母线获得并且为每个贡献于系统存储图的芯片分割出独立的良好的芯片信号。 英文原文 Mechanical Engineering in the Information Age In the early 1980s, engineers thought that massive research would be needed because shortened product development cycles encourage engineers to use available technology. Developing a revolutionary technology for use in a new product is risky and prone to failure. Taking short steps is a safer and usually more successful approach to product development. Shorter product development cycles are also beneficial in an engineering world in which both capital and labor are global. People who can design and manufacture various products can be found anywhere in the world, but containing a new idea is hard. Geographic distance is no longer a barrier to others finding out about your development six months into the process. If youve got a short development cycle, the situation is not catastrophic as long as you maintain your lead. But if youve in the midst of a six-year development process and a competitor gets wind of your work, the project coud be in more serious trouble. The idea that engineers need to create a new design to solve every problem is quickly becoming obsolete. The first step in the modern design process is to browse the Internet or other information systems to see if someone else has already designed a transmission, or a heat exchanger that is close to what you need. Through these information systems, you may discover that someone already has manufacturing drawings, numerical control tapes, and everything else required to manufacture your product. Engineers can then focus their professional competence on unsolved problems. In tackling such problems, the availability of workstations and access to the information highway dramatically enhance the capability of the engineering team and its productivity. These information age tools can give the team access to massive databases of material properties, standards, technologies, and successful designs. Such pretested designs can be downloaded for direct use or quickly modified to meet specific needs. Remote manufacturing, in which product instructions are sent out over a network, is also possible. You could end up with a virtual company where you dont have to see any hardware. When the product is to the customer can be made to ensure that the product you designed is working according to the specifications. Although all of these developments wont apply equally to every company, the potential is there. Custom design used to be left to small companies. Big companies sneered at it they hated the idea of dealing with niche markets or small-volume custom solutions. “Here is my product,” one of the big companies would say. “This is the best we can make it you ought to like it. If you dont, theres a smaller company down the street that will work on your problem.” Today, nearly every market is a niche market, because customers are selective. If you ignore the potential for tailoring your product to specific customers needs, you will lose the major part of your market share perhaps all of it. Since these niche markets are transient, your company needs to be in a position to respond to them quickly. The emergence of niche markets and design on demand has altered the way engineers conduct research.Today, research is commonly directed toward solving particular problems. Although this situation is probably temporary, much uncommitted technology, developed at government expense or written off by major corporations, is available today at very low cost. Following modest modifications, such technology can often be used directly in product development, which allows many organizations to avoid the expense of an extensive research effort. Once the technology is free of major obstacles, the research effort can focus on overcoming the barriers to commercialization rather than on pursuing new and interesting, but undefined, alternatives. When viewed in this perspective, engineering research must focus primarily on removing the barriers to rapid commercialization of known technologies, Much of this effort must address quality and reliability concerns, which are foremost in the minds of todays consumers. Clearly, a reputation for poor quality is synonymous with bad business. Everything possible including thorough inspection at the end of the manufacturing line and automatic replacement of defective productsmust be done to assure that the customer receives a properly functioning product. Research has to focus on the cost benefit of factors such as reliability. As reliability increases, manufacturing costs and the final cost of the system will decrease. Having 30percent junk at the end of a production line not only costs a fortune but also creates an opportunity for a competitor to take your idea an sell it to your customers. Central to the process of improving reliability and lowering costs is the intensive and widespread use of design software, which allows engineers to speed up every stage of the design process. Shortening each stage, however, may not sufficiently reduce the time required for the entire process. Therefore, attention must also be devoted to concurrent engineering software with shared databases that can be accessed by all members of the design team. As we move more fully into the Information Age, success will require that the engineer possess some unique knowledge of and experience in both the development and the management of technology. Success will require broad knowledge and skills as well as expertise in some key technologies and disciplines； it will also require a keen awareness of the social and economic factors at work in the marketplace. Increasingly, in the future, routine problems will not justify heavy engineering expenditures, and engineers will be expected to work cooperatively in solving more challenging, more demanding problems in substantially less time, We have begun a new phase in the practice of engineering. It offers great promise and excitement as more and more problem-solving capability is p；aced in the hands of the computerized and wired engineer. To assure success, the capability of our tools and the unquenched thirst for better products and systems must be matched by the joy of creation that marks all great engineering endeavors. Mechanical engineering is a great profession, and it will become even greater as we make the most of the opportunities offered by the Information Age. A microprocessor system can be described at a number of different levels of complexity. The least complex form is that of a simple block diagram describing the interconnection and flow of information between functional blocks and will be used to examine the operation of a microprocessor system. All microprocessor systems contain a central processing uniy (CPU),program and data memory and input and output(I/O) devices. The memory section contains both non-volatile read only memory (ROM) as program memory and volatile random access memory (RAM) as read/write data memory. For each type of memory there are a number of different types of devices, such as erasable ROMs and static or dynamic RAMs, each of which is chosen for an application based on its cost and function. An analogue input channel to the microprocessor system is provided by the analogue to digital (A/D) converter and may be used to connect a device such as an analogue sensor. An analogue output channel is provided by the digital to analogue (D/A) converter and could be used to control an output transducer such as an electric motor. The parallel I/O device provides a number of individual lines. In output mode these can be programmed to provide logic levels 1 or 0 to activate binary (on/off) devices such as lamps. In input mode it allows the microprocessor to read the state of switches and other binary devices. The serial I/O device is used to provide communications with other microprocessor systems or with an operator console used to configure the system for various operational modes. The level and power specifications of the interfacing signals of the microprocessor system are frequently incompatible with the signal specifications of the devices which are to be interfaced to it. For example, the output voltage of a D/A converter may typically be in the range 0-5 volts and be capable of supplying only a few milliamperes of current, while the electric motor may require a control voltage range of plus and minus 12 volts at a maximum current of 1 ampere. Consequently, additional analogue interface circuitry is often necessary to perform functions such as signal level shifting, amplification and filtering. All these devices are interfaced to the CPU by means of a system bus which is itself made up form an address bus , a data bus and a control bus. Physically, a bus is simply a collection of parallel interconnections between two or more devices. The number of lines contained in each bus is dependent on the type of microprocessor used in the system and the function of the bus. we assume that the address bus has sixteen lines, the data bus has eight lines, and the control bus contains an arbitrary number of lines depending on the control functiojs provided by the CPU. The concepts of address and data are fundamental to the operation of a stored program computer and form a feature of all microprocessors and computes. The memory will consist of a number of memory locations capable of storing data written to them by the CPU over the data bus, each memory location is uniquely identified to the CPU by a number called its address. The CPU controls the address and control bus lines in order to write or read information to or from the memory or I/O devices. If the CPU wished to write the binary number into a memory location which had the address, the CPU would first place the address on to the address bus, then place the number as data onto the data bus. Control lines in the control bus would then be activated to cause the data to be loaded into the appropriate memory location. A similar procedure would be used if the CPU was then to read a memory address, except this time the flow of data would be from the memory to the CPU. After the CPU had placed the address of the required memory location on the address bus, it would indicate to the memory would respond by placing the contents of the memory location as data on to the data bus, and this would then be read by the CPU. Within the system bus, the address bus is an output bus from the CPU and an input bus to the other devices. The control bus consists of a number of lines, each of which may be either a control output from the CPU or a control input to the CPU is reading or writing data. All devices in the system are connected together by the data bus and this means that, potentially at least, the outputs of all the memory and I/O devices are connected. If this were in fact to happen it would cause the destruction of several or all of the connected devices, because some devices would be trying to drive the bus to a logic 1 state while others were trying to drive it to a logic 0 state. To avoid this problem, the data bus connections of each device are capable of being placed into a third, high impedance state where the device no longer has any loading effect on the bus. This allows other devices connected to the data bus to output their data on to this bus when they are correctly enabled, which in turn means that only one device should be enabled at any one time to the data bus. The ability of a device to be either at a logic 1 or at a logic 0 or in a high impedance condition in relation to the data bus is called a tristate condition, and is an essential feature of devices which share a common data bus. The data bus has eight lines, and hence the range of values which a single item of data can take is restricted to that which can be represented by 8 binary digits or bits. Eight bits are referred to as a byte, and can represent a decimal number from 0 to 255. likewise the address bus, consisting of sixteen lines, can represent an address number in the range 0 to 216-1 or 65535. this number is usually abbreviated to the binary equivalent of the decimal number and expressed as 64k, where 1k is equal to 1024 in the binary number system. To the CPU, the system appears as a series of 64k consecutive memory locations, each capable of storing an 8 bit binary value. The CPU will contain a number of registers which are used to manipulate the data and its addresses. In the example chosen, these data registers will be 8 bit registers and all data bit CPU, However, registers which support address manipulations will be performed on 8 bit quantities. The CPU is therefore referred to as an 8 bit CPU. However, registers which support address manipulations need to be 16 bit registers because of t