第一篇:电子专业英语最终翻译
1G..site20世纪70年代,1g模拟制式的无线通信系统见证了两项重要的技术改进,微处理器的发明及无线电话和小区之间控制链路的数字化
An important..point有理想运放的特性可以得出一个重要的结论,级放大器的反向输入端无电流流过
Another example..eath另一个例子就是将由太空船拍摄的火星图片传送至地球上的地面工作站
A rugged..individually成像问题要求能识别个体目标,采用粗糙的分割方法似的距离要求有很大差距
A television..network电视网关是一个通信设备,他讲电视媒体服务器接收的音视频转换成收看者或不同网络能使用的形式
a lot..variables具体说明随笔变量的精确分布需要大量信息,说明两个或者两个以上的变量的联合分布甚至需要更多的信息
although it is虽然运算放大器看成一个具有理想输入输出特性的黑盒子是实用且简单的但是了解他北部工作原理仍是很重要的,这样的话,人们能够处理由其内部寄生电容引起的等
a signa..phenomenonl一个信号正式定义为:一个承载着一个物理现象本质信息的单变量或多变量函数
a basic..theory 这本书最基本的前提是多数实际的dsp技术可以学习和使用为不存在传统的关于详细的数学和理论的障碍
although large尽管大规模的图像处理系统仍然被出售用于大量的图像应用,例如卫星图像的处理,继续趋向于小型化,并且混合通用的电脑带有专门的图像处理 All of the新的蜂窝系统都是数字化的,即采用二进制接口,这样原则上可以用于声音或数据。由于这些蜂窝系统和他们的标准与案件集中在通话上,蜂窝系统中当前的数据比率和延迟基本上是有声音需要决定的。
Connection with..make切换时用户先断开和旧的nodeb之间的链接,再与新的nodeb建立连接,因此这样的切换也被称为先开后合Central to压缩系统基于一个视频广播网络,他的工作是用于小量网络带宽传输高质量的视频和音频给终端用户。IPTV压缩系统主要的任务是减少信息的存储量,同时保持视频流和音频流的质量。
Description,also图像描述也称为特征选取,是指从图像中提取某些特征,这些特征或者产生人们感兴趣的定量信息,或者作为区别不同目标类别的基础 Digital media..content数字媒体压缩对数字信号进行分析,并且利用分析信息将表示真是信号形状的高速数字信号转换为表示真实内容的低速数字信号 digital signal..matching关于声音问题的数字信号处理的一般方法有两步。特征匹配和特征提取
dsp is Dsp是种数学算法,这项技术用于处理真是信号有他们转化位数字形式之后其中包括许多目标,例如增强视图,识别和产生语言,压缩存储数据的传输等 Each cell每一部小区电话,当他拨打时会通过它的天线和电磁辐射与有最好交流路径的基站相连。给定区域内的基站通过高速电缆、光线或者微波联络的方式与移动电话交换中心连接
For engineering….theory对于工科学生,学习概率论时应谨记,概率就是理想的比例
Frequency response…amplifier对于理想放大器而言,交流只不过是快速变化的直流,所以其频率响应是一条水平直线,带宽无限
For any…whatsoever对任意线性时不变系统t,只要已知冲力响应h(t)(即系统对单位冲力函数的响应)就可以不用考虑t将经过缩放和位移变换的h(t)相加,即可得到系统t对任意输入的响应
For convenience..design由于在电路实现时必须将离散时间信号转换位数字信号,围在分析与设计过程中则将数字信号看作是离散时间信号,为方便起见,我们不加区别的使用数字信号与离散信号
for any对于任何随机变量来说,分布函数两点间的差值等于这个随机变量落在两点之间的概率值
Fiber cable线缆和分光器是无源的光学元件。在引导光波通过网络上对无源元件的使用,消除了远程功率的需要,这样减少了远程的费用。
It seems that…to be consistent看来,人们对这种不确定性陷入了自己的主管判断中,但是由此产生的概率必须遵循某些准则以保持一致
if a small voltage…small假如在反向输入端测得与相同输入端之间存在一小电压,这放大器的输出电压与该输入电压极性相反且其数字会一直增加(可以是无穷大)直至输入电压变为无穷小为止
in control and..circuitry在控制与仪器仪表应用中,反响放大器的实际价值在于,利用它可以很容易地调整多虚的输入阻抗和争议一直影响管电路的要求 instead,we must measured因此,必须找到一些方法,通过一定数量的测量就能推断出系统对其他未经测量的输入如何影响
In quantization..occur量化时,如果离散时间信号的幅度与量化电平不一致,那么就应采用截断或四舍五入的方式将它近似为某个量化电平,两种情况会产生误差 Iptv is..reliabilityiptv是指ip网络上传送注入电视视频文本图形和数据的多媒体业务,他可提供所需的服务质量,保证安全性交互性和可靠性
in general 通常。随机事件的概率p可以解释为:如果一个实验重复最大量次,这个结果能被观察到百分之100p次
in the case对于理想运算放大器,电路可以通过在反向输入端零电压和零电流的理想求和点约束来简化
if the input如果一个线性系统的输入是正弦波,则输出也是正弦波,确切的说频率也相同
in fact..w实际上,如果一个离散时间序列是绝对可加的,那么和现在连续时间序列情况下一样,它的频谱是一个关于w的又接连续函数
interestin在过去的几年里,随着用于网络应用的数字图像的增长,彩色图像处理的兴趣也增加了
image restoration图像恢复可以用于恢复一个已知的失真图像。有一个客观的标准可以使用
mass大的存储容量在图像处理的应用中是必须的,一个图像尺寸是1024x1204像素,其中每个密集的像素是八个比特,需要一兆的存储空间如果图像不压缩 in archeology在考古学中,图像处理地方法已经成功的回复模糊的画面,并且是唯一可以利用的关于稀少的丢失破坏的人工制品的记录在他们被破坏之后 interest in..perception数字图像处理方法的兴趣起源于两个主要的领域,提高人类对有图像信息的解释,用于存储的图像数据的处理。代表自制机器的感觉
It appears看起来许多无线的点,尤其是那些在蜂窝或当地区域网络中的位置,包含了相对少数有意义的协调的波形,如果带宽足够大能够包含这些波形,那增益会远大于上个例子所提到的J just as正如我们可以将任何信号表示为一系列经过平移缩放的脉冲之和一样,我们也可以把任意一个信号表示层一系列不同频率正弦信号之和
Multicast transmission,.receivers多播传输是一到多的媒体传送过程,他发送单个消息或信息传输,其中包含一个指定的地址以允许网络中的多个分散节点能接收及把 的信号重传给过个接收者
more generally多数情况信号处理是一个提取增强存储和传送有用信息的操作,有用和不需要信息的区别既有主观的也有客观的O operational 运算放大器可以有闭环操作或者开环操作,操作取决与是否使用了反馈
One approach信道测量的一种方法是为每一个传输包分配一定的份额来满足这个目的。在这期间,一个已知的探通序列已被传输,接受者用这个已知序列估计当前信道中的离散时间基带模型的值,或者用于测量连续时间基带模型上的实际波形
Owing to由于近两年在设备和组网费用上的减少,引人瞩目的光线网络的使用有显著增加,他用来传输新兴的基于ip的服务,例如IPTV。另外光线链路提供终端专用的很好的适于IPTV内容传输的链接
On the..inputs另一方面,其他领域如计算机视觉,其最终目的是用计算机来模仿人类视觉,即根据视觉输入来进行学习。推理及出响应
systems are如果每一个有界的输入引起一个有界输出则定义系统达到稳定,离散时间系统达到稳定的条件是h(x)的所有几点都位于z平面的单位圆内 system using系统使用dsp的方法可以开发有用的软件运行在一般的计算机上,因此dps是相对方便的用于开发和测试,并且软件是轻便的This concept…class概率的这种定义是客观的,它应用于每次观测,并以一种相对的方式度量其结果归入相应类别的可能性
This may seem..hardware由于计算机程序是在确定的硬件上运行的指令,这似乎是个奢求
The successive..in practice序列{}中的元素看似互不相关,尽管在序列中存在某些结构(该序列最终的确会重复)但这并不影响实际应用
Though the ideal…cases尽管模型与实际电路相差甚远,比如,理想运放具有无线宽带和无穷大的增益,但需要明白的是,本节利用理想运放推导出的闭环增益公式可直接应用于实际电路,多数情况下两者相差仅为千分之几
The type of…x(t).time称取决于某一独立变量,即时间t的这类信号为一维信号,用x(t)表示
This type..disturbancesa不过,不过这种表示法易受噪声,电源起伏及其他干扰的影响而位于采用
To process..singnal要以数字化的方式处理模拟信号,应先对模拟信号在时间上离散化以生产离散时间信号然后对其幅值量化以生产数字信号
The roots..available数字信号处理始于二十世纪六七十年代,当时数字计算机刚问世
Thus what..book因此,书中所说的数字图像处理既包括输入输出都是图像的过程,也包括从图像中提取特征其他过程,直至对个体目标进行识别也属于本书的范畴
Two chapters..well我们将用两章的篇幅来介绍图像增强,并不是因为它比书中其他的内容更重要,二十把它作为引领读者学习其他章节的一个途径
The manner..sigal花圃中耙的拾草方式与rake接收机中各耙指协同工作以恢复多路发送信号相似
The interference..control当允许新的呼叫时,干扰就会增加。为了避免由于干扰增加而带来的小区覆盖下降,系统引入了准入控制机制
The admission.quality由于系统能未申请了不同容量和质量的业务提供服务,因此在上行链路和下行链路中都是用准入控制
This example..users这个例子示意性地画出了正在观看电影的终端用户,他所看的片源最初是由离终端用户一定距离,而且相隔几个交换设备的媒体中心所提供的 The ubiquity..world宽带连接无处不在,这意味着每个人都能从家里或者办公室一ip多播的形式向其互联网服务提供商直播视频流,使全世界的人都能访问到 the binomial在所有的离散随机变量中,二项式和泊松分布是应用最广泛的离散分布,由于概率分布在统计质量控制中的重要性,它对于工程师们来说特别有用 the operational。design运算放大器是非常有效的多功能的设备,他的应用跨越了广阔的电子工业领域以适应信号调节整形,特殊转移函数,模拟仪器,模拟计
算和特殊系统设计的需求
the fouruer傅里叶级数分解是数字领域傅里叶分析的基础,或是高级的拉布拉斯变换,多数极重要的都dsp算法都是以这些方面的技术为基础的the resulting作为结果的二进制码流再添加长的为噪声序列后会处在1.228Mbps。这个码流被复制成两个在余弦波和正选搬移上优先于正交调制的码流。
The mechanism这个机制通过并发式的IPTV包运行,这些IPTV包跨越了某些信道。通过多个信道的包的分布会为调制解调器带来困难,因为信道受抖动和等得时间的影响,如果是这种情况,报将无法到达。
The backbone一个IPTV联网的底成结构的核心是要求在该IPTV数据中心和最后一英里的中区分布网络之间以高速度驱动大量的视屏内容。有一些不同类型的中区传输标准证实对于保证高可靠性、多路径和链路是必要的。
When the responses…system如果系统对经时移后的相统计里产生的具有相应时移的相同响应,我们就得到一种特殊的线性系统称为是不变系统
While this…high尽管该结论并非严格的数学证明,但有理由相信其可信度很高
WhileSuperposition and..inputs叠加与卷积听起来可能有些抽象,但具体可等效解释为:当且仅当系统的响应克表示为输入信号的加权时,该系统才实现形式不变系统
when feedback 当反馈被用于运算放大器时,电路的闭环增益取决于起作用的输入与反馈阻抗的比例
第二篇:机械电子专业英语翻译
Quality Control Fundamentals质量控制基本原理 Quality质量
Quality has become one of the most important consumer decision factors in the selection among competing products and services.The phenomenon is widespread, regardless of whether the consumer is an individual, an industrial organization, a retail store, a bank or financial institution, or a military defense program.Consequently, understanding and
improving quality are key factors leading to business success, growth, and enhanced competitiveness.There is a substantial return on investment from improved quality and from successfully employing quality as an integral part of overall business strategy.质量是消费者在激烈的产品和服务竞争中进行选择的一个重要因素.不管这个消费者是个人、产业组织、零售店或防务工程,这个想象是普遍存在的.因此,关注并提升质量是取得成功、发展并强化竞争力的关键因素.投资质量的提升并把质量作为经营策略的主要部分将会得到极大地回报.We may define quality in many ways.Most people have a conceptual understanding of quality as relating to one or more desirable characteristics that a product or service should possess.Although this conceptual understanding is certainly a useful starting point, we will give a more precise and useful definition.我们对质量有很多种定义.许多人在观念上把质量理解为产品或服务拥有一个或更多满意的性能.尽管这种概念性理解是有效地,我们将给出更精确、有效地定义.Quality----characteristic or property consisting of several well-defined technical and aesthetic, hence subjective, considerations;conformance to design(customer)requirement.质量-特性或性能中包含几种明确定义的技术的美学的,因此主观考虑;满足设计(顾客)需求.Quality control------detecting poor quality(nonconformance)in manufactured products and taking corrective action to eliminate it.质量控制-检测在工业产品中检测不合格的质量(不合格品)并采取纠正措施去避免.The traditional definition of quality is based on the viewpoint that products and services must meet the requirement of those who use them.Therefore, Quality means fitness for use.传统的质量定义是产品或服务必须满足使用者的需求.因此,质量就是适用度
There are two general aspects of fitness for use: quality of design and quality of conformance.适用度一般有两个方面:设计质量和一致性的质量。
Quality by design intent refers to the various grades or levels of quality that are intentionally determined by design.All goods and services are produced in various grades or levels of quality.These variations in grades or levels of quality are intentional, and, consequently, the appropriate technical term is quality of design.设计意图的质量指的是设计中故意设计的各种等级或质量等级。所有的商品和服务都是在不同的等级或质量等级中产生的。这些变化的等级或质量水平是故意的,因此,适当的技术术语称之为设计质量。
Quality of conformance refers to how well the product conforms to specifications required by design.产品质量的一致性是指如何符合规范设计的要求。
Quality of conformance is influenced by a number of factors, including the choice of manufacturing processes, the training and supervision of the workforce, the types of process controls, tests, and inspection activities that are employed, the extent to which these procedures are followed, and the motivation of the workforce to achieve quality.一致性质量受到很多因素的影响,包括生产流程的选择、员工的培训和监督,所采用的过程控制,测试,和检查活动的类型,这些程序被遵循的程度 ,激励员工来实现质量。
Unfortunately, this definition has become associated more with the conformance aspect of quality than with design.This is in part due to the lack of formal education most designers and engineers receive in quality engineering methodology.This also leads to much less focus on the customer and more of a ―conformance-to-specifications‖ approach to quality, regardless of whether the product, even when produced to standards, was actually ―fit-foruse‖ by the customer.Also, there is still a widespread belief that quality is a problem that can be dealt with solely in manufacturing, or that the only way quality can be improved is by ―gold-plating‖ the product.不幸的是,相对于设计,这个定义更多的关于质量的一致性。这部分是由于大多数设计师和工程师缺乏质量工程方法的正规教育。这也导致更少地关注客户和更多关注质量与规格一致, 无论产品,即使生产标准,实际上是“适合使用”的客户。同时,普遍仍认为,在生产制造中质量问题完全可以解决, 或者唯一的可以提高质的方式是给产品“镀金”。
We prefer a modern definition of quality: Quality is inversely proportional to variability.Note that this definition implies that if variability in the important characteristics of a product decreases, the quality of the product increases.As an example of the operational effectiveness of this definition, a few years ago, one of the automobile companies in the United States performed a comparative study of a transmission that was manufactured in a domestic plant and by a Japanese supplier.我们倾向于质量的现代定义:质量与变化成反比。请注意,这个定义意味着如果产品的重要特征的变化减少,产品的质量就会提高。举一个这个定义的操作效益的例子,几年前, 美国的一个汽车公司进行了一个在国内工厂制造过程的传输和由日本供应商制造过程的传输的比较研究。
An analysis of warranty claims and repair costs indicated that there was a striking difference between the two sources of production, with the Japanese-produced transmission having much lower costs, as shown in Fig.5.1.As part of the study to discover the cause of this difference in cost and performance, the company selected random samples of transmissions from each plant, disassembled them, and measured several critical quality characteristics.保修索赔和维修费用的分析表明,两者的生产有着显着的区别,如图5.1所示,日本制造的运输成本很低。这项研究的一部分是发现成本和表现中这种差异的原因,公司从每个工厂随机选择抽样,拆卸样本,并测量了几个关键的质量特性。
Figure 5.2 is generally representative of the results of this study.Note that the distribution of the critical characteristics for the transmissions manufactured in the United States takes up about 75% of the width of the specifications, implying that very few nonconforming units would be produced.In fact, the plant was producing at a quality level that was quite good, based on the generally accepted view of quality within the company.However, the Japanese plant produced transmissions for which the same critical characteristics take up only about 25% of the specification band.As a result, there is considerably less variability in the critical quality characteristics of the Japanese-built transmissions in comparison to those built in the United States.图5.2通常是这项研究的结果的代表。注意的是美国生产传输的临界特征的分布 占宽度规格的75%左右,这意味着不相容的产品很少。事实上, 根据公司内部的质量标准,工厂生产的质量水平很好,然而,日本工厂的生产传输的相同的临界特征规范只占用约25%的规格带。因此,日本建立的生产传输中的关键质量特征的变化要比美国的少很多。
There are two obvious questions here: Why did the Japanese do this? How did they do this? The answer to the ―why‖ question is obvious from examination of Fig.5.1.Reduced variability has directly translated into lower costs。Furthermore, the Japanese-built transmissions shifted gears more smoothly, ran more quietly, and were generally perceived by the customer as superior to those built domestically.Fewer repairs and warranty claims means less rework and the reduction of wasted time, effort, and money.Thus, quality truly is inversely proportional to variability.How did the Japanese do this? The answer lies in the systematic and effective use of the methods described in this text.这里有两个明显的问题:为什么日本人这样做呢?他们是如何做到这一点呢? 再看图5.1,“为什么”的问题的答案是显而易见的。减少的变化直接转化为低成本。此外,日本造的变速齿轮更顺畅,更安静,客户通常认为日本的变速齿轮要比国内的好。更少的维修和保修索赔意味着很少的返工,节约时间 ,精力,和金钱。因此,质量真的是与变化成反比。日本人是怎么做的呢?答案就在于系统和有效地使用本文中描述的方法。
Dimensions of Quality质量维度 The quality of a product can be described and evaluated in several ways.It is often very important to differentiate these different dimensions of quality.Garvin provides an excellent discussion of eight components or dimensions of quality.We summarize his key points concerning these dimensions of quality as follows: 一个产品的质量可以用几种方法来描述和评价。区分这些不同维度的质量往往是很重要的。加文 对于质量的八种要素做了一个很好的讨论。我们总结了他的关键点,这些尺寸的质量如下:
Performance –product does intended job
表现—产品满足特定功能 Reliability—product is available 可靠性----产品是可用的
Durability—product lasts for a reasonable time 持久性---产品能使用一个合理的时间 Serviceability—product is easy to repair/service
维护性---产品维修维护方便
Aesthetics—product has acceptable/appealing appearance
美观---产品具有可接受或吸引人的外观
Features—product has capabilities beyond basic performance 功能性---产品具有超越基本功能的功能
Perceived Quality—product & company have good reputation;measured by customer loyalty 感知质量—产品和公司在消费者中具有良好的声誉。
Conformance to Standards—product made consistent with designer intent(and consistent with industry & national standards)标准一致---制造的产品符合设计师的意图(并符合行业和国家标准)。
Quality Improvement质量的提升 Quality improvement is the reduction of variability in processes and products.Excessive variability in process performance often results in waste.For example, consider the wasted money, time, and effort that is associated with the repairs represented in Figure 5.1.Therefore, an alternate and frequently very useful definition is that quality improvement is the reduction of waste.质量改进是减少过程和产品中的变化。过程性能的过度变化往往导致浪费。例如,图5.1所反映的维修中浪费的金钱,时间和精力。因此,一个替代的,通常是非常有用的定义是,质量改进是减少浪费。
Implementing quality improvement: management must 实施质量改进:管理
Evaluate dimensions of quality as they pertain to their business objectives(assuming the objectives are defined);评估质量维度与他们的业务目标(假设定义了目标); Think strategically about quality;战略性地考虑质量;
Recognize critical role of suppliers in quality management strategies;认识到供应商在质量管理战略中的重要作用;
Recognize that everyone in the organization is responsible for quality;认识到组织中的每个人都对质量富有责任;
Recognize that statistical quality control techniques communicate both problems & solution;认识到统计质量控制技术,沟通问题和解决方案;
Implement effective quality improvement programs tailored to their business;针对他们的业务实施有效的质量改进方案;
Total quality management;全面质量管理;
Quality improvement benefits—business growth;enhanced competition;cost reduction;reduced product liability;improved productivity.质量改进的效益----业务增长;增强竞争;降低成本;减少产品债务;提高生产率。
Quality Engineering Terminology质量工程术语
Every product possesses a number of elements that jointly describe what the user or consumer thinks of as quality.These parameters are often called quality characteristics.Quality characteristics –-Physical;Sensory;Time Orientation;can be attributes or variable.每个产品都有许多描述用户或消费者心目中的质量的要素。这些参数通常被称为质量特性。
品质特性–身体;感官;时间方向;可以是属性或变量。
Quality engineering—the set of operational, managerial and engineering activities used to ensure that quality characteristics of a product are at nominal or the required levels.质量工程---一套确保产品的质量特性是在名义或所需的水平操作,管理和工程活动。
Statistical methods—applied to measurements for product’s quality characteristics, they are usually the result of the engineering design process for the product.统计方法---用于测量产品的质量特性,通常是产品的工程设计过程的结果。Quality measurement---compare measured value to nominal or target value for characteristic;values bounded by allowable limits, namely, upper specification limit(USL)and low specification limit(LSL)(determined by design engineer);values outside limits are considered to be nonconforming, hence, product is defective.质量测量——将质量的测量值与真值相比较,特征值被范围所限制,即规范上限(USL)和规范下极限(LSL)(由设计工程师决定);特征值外部限制被认为是不一致的,因此,产品是有缺陷的。
Concurrent engineering---multi-disciplinary, team-based approach to design(early in design process).并行工程---多学科,以团队为基础的设计方法(多在早期的设计过程)。
History of Quality Methodology质量方法学史
Quality always has been an integral part of virtually all products and services.However, our awareness of its importance and the introduction of formal methods for quality control and improvement have been an evolutionary development.Table 5.1 presents a timeline of some the important milestones in this evolutionary process.质量几乎一直是所有产品和服务的一个组成部分。然而,我们意识到它的重要性,并介绍了正式的质量控制和改进的方法,一直是一个进化的发展。表5.1给出了一些在这个进化过程中的重要里程碑的时间线。
A Timeline of Quality Methods质量测量方法的时间线
1700—1900 Quality was largely determined by the efforts of an individual craftsman.Eli Whitney introduces standardized, interchangeable parts to simplify assembly.质量在很大程度上取决于个人的努力。伊莱·惠特尼介绍标准化,可互换的零件以简化装配。1875 Frederick W.Taylor introduces principles of Scientific Management;division of labor &work standards;improved productivity.1875年弗雷德里克·W·泰勒 介绍了科学管理的原则;劳动分工和劳动标准;提高生产率。
1900–1930 Henry Ford—the assembly line—further refinement of work methods to improve productivity and quality;Ford developed mistake-proof assembly concepts, self-checking, and in-process inspection.亨利福特的装配线进一步细化工作方法以提高生产率和质量;福特开发的防误装配的概念,自我检查和中间验收,1924 Walter.A.Shewhart introduces the control chart concept in a Bell Laboratories technical memorandum.沃尔特在贝尔实验室的技术备忘录介绍了控制图的概念。1928 Acceptance sampling methodology is developed and refined by H.F.Dodge and H.G.Roming at Bell Labs.H.F.道奇和H.G.漫游在贝尔实验室开发和总结了验收抽样方法。1940 The U.S.War Department publishes a guide for using control charts to analyze process data.美国战争部出版了一份使用控制图来分析处理数据指南。
1946 ASQC formed to promote use of quality improvement methods for products & service.建立美国质量控制协会以促进使用产品与服务质量改进方法。
1946–1949 Deming is invited to japan by the Economic and Scientific Services Section of the U.S.War Department to help occupation forces in rebuilding Japanese industry.He was invited to give statistical quality control seminars to Japanese industry.戴明被美国国防部的经济和科学服务部邀请到日本帮助占领军重建日本工业。他被邀请给日本工业的统计质量控制开研讨会。
1951 Dr.A.V.Feigenbaum publishes the first edition of his book, Total Quality Control.G.E.P.Box & Wilson published work on designed experiments & process optimization methods.在1951年,费根鲍姆博士出版了他的第一本书---全面质量控制。威尔逊发明了工作流程优化设计和在线实验的方法。
1960s Courses in statistical quality control become widespread in industrial engineering academic programs.Zero defects(ZD)programs are introduced in certain U.S.industries.在20世纪60年代的统计质量控制的广泛的课程成为工业工程学术课程。零缺陷(ZD)计划被美国工业产业引进。
1989 Motorola’s six-sigma initiative began.摩托罗拉开始倡议六西格玛。
1990s ISO 9000 certification activities increase in U.S.industry;applicants for the Baldrige award grow steadily;many states sponsor quality awards based on the Baldrige criteria.上世纪90年代,在美国工业行业,ISO 9000认证活动增加;对波多里奇奖的申请稳步增长;许多国家赞助基于波多里奇标准的质量奖。
1995 Many undergraduate engineering programs require formal courses in statistical techniques, focusing on basic methods for process characterization and improvement.许多本科工程项目需要专注于过程特性和改进的基本方法 统计技术的正式课程。
1997 Motorola’s six-sigma approach spreads to other industries.1997年,摩托罗拉的六西格玛方法扩展到其他行业。
1998 The American Societies for Quality Control becomes the
American Society for quality, attempting to indicate the broader aspects of the quality improvement field.1998年,美国质量控制协会成为美国质量学会,其试图表明更广泛的质量改善领域。
Statistical Methods统计方法 Statistical process control(SPC): use control charts to reduce variability & maintain measure of process quality within acceptable limits, namely, upper control limit(UCL)and lower control limit(LCL).统计过程控制(SPC):使用控制图来减少变化及维持质量测量在可接受的范围内,即控制上限(UCL)和控制下限(LCL)。
Statistically designed experiment: used to discover key variables that influence quality characteristics of interest;systematically vary process controllable input factors to determine their effects on output product parameters.统计学设计的实验:用于发现影响质量特性的关键变量,系统变化的过程可控的输入因素,以确定其对输出产品参数的影响。
Process modeling: captures the relationship between input and output variable of process;statistical such as regression or time-series analyses, also, neural network techniques, used to determine the nature &magnitude of adjustments required to bring process back into control.过程建模:捕捉过程中的输入和输出变量之间的关系;统计,如回归或时间序列分析,神经网络技术,用于确定控制过程中所需调整的性质和幅度。
Acceptance sampling: inspection & classification of sampled units, selected at random, from larger batch of product(lot)for the purpose of determining disposition of lot;decision may be to accept, reject, or rework lot;emphasizes conformance to requirements approach to quality control.验收抽样: 从大批产品(很多)检查和分类抽样单位,随机选择以确定处置方式, 决定可能是接受,拒绝,或返工;强调符合要求的质量控制方法。
Manufacturing Process Characteristics制造工艺特点
Random variations----caused by variability among operators, Raw materials, machine vibrations, and environmental changes;usually uncontrollable;regarded as process noise;no particular pattern or trend.随机变化--由操作者,原材料,机器振动,和环境改变中的变化造成;通常无法控制的;被视为过程噪声;没有特定的模式或趋势。
Assignable variations---exception from normal operating conditions, e.g, operator mistakes;defective raw materials;tool failures;machine malfunctions, can be traced to specific causes.可分配的变化---从正常工作条件下,例如,操作者错误的异常;有缺陷的原料;工具失效;机器故障,都可以追溯到具体原因。
Machining processes are capable of tolerances of +_0.002 in(+_0.05), e.g, sand castings generally have tolerances of 10 to 20 times those used for machined parts.加工过程能够在(+_0.05)公差允许+-0.002,比如沙铸件的公差通常是用于加工零件的公差的10至20倍。
Total Quality Management(TQM)全面质量管理
Total quality management(TQM)is a strategy for implementing and managing quality improvement activities on an organization wide basis.TQM began in the early 1980s, with the philosophies of Deming and Juran as the focal point.It evolved into a broader spectrum of concepts and ideas, involving participative organizations and work culture, customer focus, supplier quality improvement, integration of the quality system with business goals, and many other activities to focus all elements of the organization around the quality improvement goal.Typically, organizations that have implemented a TQM approach to quality improvement have quality councils or high-level teams that deal with strategic quality initiatives, workforce-level teams that focus on routine production or business activities, and cross-functional teams that address specific quality improvement issues.全面质量管理(TQM)在组织基础中是一种实现和管理质量改进活动的战略。全面质量管理始于上世纪80年代初,随着戴明和朱兰的理念为焦点。它演变成一个涉及参与组织和工作文化,关注客户,供应商的质量改进,质量体系与业务目标的整合,以及许多其他的围绕质量改进目标的组织的所有元素的活动的概念。通常情况下,已经实施了全面质量管理方法以提升质量的组织具有处理质量的战略举措的质量委员会或者高层团队,聚焦日常生产、经营活动的劳动力水平的队伍,解决具体的质量改进问题的跨 职能团队。
机械专业词汇
Manufacturing process 制造工艺 Serviceability 维护性
Conformance to standards 标准一致 Quality engineering 质量工程 Measured value 测量值 Nominal value 真值 Multi-disciplinary 多学科的 Concurrent engineering 并行工程 Standardized parts 标准件 Six-sigma 六西格玛 LSL 下限 USL 上限
ISO9000 质量保证体系9000 Process modeling 过程建模 Process control 过程控制 TQM全面质量管理 Sand casting 沙铸件
Acceptance sampling 进料抽样实验 Assignable variation 系统变差 Critical dimension 临界大小 科技特殊句式 1.动名词做主语
Understanding and improving quality are key factors leading to business success, growth, and enhanced competitiveness.2.非谓语动词做定语
Quality----characteristic or property consisting of several well-defined technical and aesthetic, hence subjective, considerations;conformance to design(customer)requirement.3.复杂长句
This also leads to much less focus on the customer and more of a ―conformance-to-specifications‖ approach to quality, regardless of whether the product, even when produced to standards, was actually ―fit-for use‖ by the customer.4.名词短语
There are two general aspects of fitness for use: quality of design and quality of conformance.5.复杂长句 Organizations that have implemented a TQM approach to quality improvement have quality councils or high-level teams that deal with strategic quality initiatives, workforce-level teams that focus on routine production or business activities, and cross-functional teams that address specific quality improvement issues.典型句式
1.定义句式
Quality by design intent refers to the various grades or levels of quality that are intentionally determined by design.Paradigm refers to models of inquiry that guides scientific work
2.满足标准
The traditional definition of quality is based on the viewpoint that products and services must meet the requirement of those who use them.All structural steel, plate and sheet meet the requirements of certain specifications.3.比例关系
Quality is inversely proportional to variability.Al Most objects are big in proportion to the size of an atom but small in proportion to the size of the sun.4.图表所占比例
The Japanese plant produced transmissions for which the same critical characteristics take up only about 25% of the specification band.Girl students accounted for 47.3 percent of total primary school enrollment.Figure 4.2 gives the results of the experiment.5.研究表明
An analysis of warranty claims and repair costs indicated that there was a striking difference between the two sources of production.A study indicated that the successful language learners are same at many aspects.6.结论
Therefore, an alternate and frequently very useful definition is that quality improvement is the reduction of waste.It can be concluded that baud rate is very important to the telephone engineer.7.举例
For example, consider the wasted money, time, and effort that is associated with the repairs represented in Figure 5.1.For example, consultants and freelancers interviewed for this article set targets from$ 50 to$ 300 per hour.8.相关性
This definition has become associated more with the conformance aspect of quality than with design.The density of a soil is directly associated to its bearing capability.9.图表引用
Figure 5.2 is generally representative of the results of this study.Figure 4.2 gives the results of the experiment.10.It---that语句
It is often very important to differentiate these different dimensions of quality.It is evident that a well lubricated bearing turns more easily than a dry one.
第三篇:专业英语翻译
Freeways,especially those built to Interstate standardsare the safest of the various classes of highways.高速公路,尤其是那些按照州际公路标准建造的是各种公路里面最安全的.While control of access, which limits vehicle conflicts(车辆冲突), isa primary factor in relatively low accident, injury,and fatality rates(事故,死亡率), other design features, such as wide medians and shoulders roadsides clear of obstructions, and the extensive use of protective barriers(护栏), are key factors as well.出入口控制减少车辆冲突,是获得较低的交通事故率和伤亡率的一个主 要因素。另外,其他的设计特性,如较宽的中央分隔带和较宽的路肩、路边无障碍物、大量采用防护栏等也是关键要素。
The higher design speeds(设计速度)used for freeways result in long sight distances(视距)due to long radiushorizontal curves and long vertical curves, and otherdesirable design features that create a safe drivingenvironment.高速公路采用较高的设计速度导致的长视距是由于大半径水平曲线和长的竖曲线,以及其他创造安全的驾驶环境的适宜的设计特性.Although most of the nation’s freeways enjoy this
relatively high level of design and safety, there are many opportunities for further enhancements.尽管全国绝大部分高速公路最喜欢这样的设计和安全性比较高的水平,但还是有很多地方需要进一步增强。
Safety improvements on freeways can also result in substantial savings in life and property(生命和财产)because freeways carry 25 percent of the nation’s total traffic.高速公路安全方面的改善,还会节约大量的生命财产资源,因为高速公路流量占了全国的总流量的25﹪。
Selecting the design speed for a freeway is an important safety element because most geometric criteria(准则,标准)related to or depend on it.选择高速公路的设计速度是一件重要的安全因素因为大部分的几何设计标准都是与它相关或者取决于它
In general, 110 kilometers per hour(km/h)should be the design speed for the mainline of a freeway , but it may need to be lower in areas of severe terrain or heavy development.一般来说,110千米每小时应该作为高速公路主干道的设计速度,但是在崎岖的地区或者施工难度大的地区可能需要降低。
For reconstruction, rehabilitation, and resurfacing(3R)
projects, the design speed should not be less than the original design speed or the current legal speed limit of that highway section.对于重建,恢复铺新路面工程,设计速度不应该低于平时设计速度或者那块交通干线区域的目前规定的速度限制。Design speeds for interchange ramps(立交匝道)depend on the type of ramp selected, for example , loop,diamond, or direct, and the low-volume(低交通量), running speed(行驶速度)of the intersecting highway.立交匝道的设计速度取决于砸到的选择类型,例如,环形、菱形、直线型以及低交通量,相交交通干线的运行速度。Usually, the design speed is established by the most restrictive element of the ramp, typically, the sharpest curve(小半径曲线).通常,这个设计速度被匝道的最限制的范围,典型的是小半径曲线。
Whatever design speed is selected, adequate transitions(转变、过渡)from the freeway proper and at the ramp terminal(末端、末尾)or merge point(合流点)should be developed.无论选择多大的设计速度,都应该发展来自高速公路本身的和在匝道末尾或者合流点的合适的过渡。
Safe and efficient traffic operations depend on adequate lane
and shoulder widths as outlined in A Police on Geometric Design of Highways and Streets.安全及高效的交通运作取决于按照《道路的几何尺寸的规定》设计的适当的行车线和路肩宽度。
The need to accommodate more traffic within existing or limited additional right-of-way on high-volume urban freeway has led some agencies to increase capacity by exchange full-lane or shoulder widths for additional travel lanes with reduced widths.在高交通量的城市高速公路上,在已有的或者额外有限的公路用地条件下,容纳更多的交通的需求,导致许多机构通过减小车道宽度或者路肩宽度来腾出额外的车道来提高通行能力。
Any proposed use of less-than-full-standard cross-section must be analyzed carefully on a site-by-site basis.Experience indicates that 3.3-m lane can operate safely if there are no other less-than-standard features;however, combined with shoulder-width reductions, substandard sight distance, and other features, 3.3-m lanes may not provide the same safe operation.任何少于全标准道路横截面的提议都必须建立在充分论证的基础上。经验表明,不考虑其他低于标准的因素,3.3
米得行车道宽足够保证安全。但是结合路肩宽度的减少,视距不足及其他因素,3.3米得行车道宽不能提供足够的安全度。Converting shoulder to travel lanes for additional capacity through a short bottleneck section has been shown to significantly reduce congestion-related accidents on some projects.Removing shoulders for several kilometers, however, has not had the same result.在某些项目中,在短程的瓶颈路段为了额外的通行能力,将路肩转变成行车道能显著减少由道路拥挤导致的交通事故。然而减少几公里长的路肩宽度,得不到同样的的结果。
Pavement marking, such as lane lines, edge lines, channelizing lines at interchanges and ramps, and word symbol markings, provide important information to the drivers.路面标记,像在立体交道和斜坡处的车道线,边缘线,通道线以及文字和符号标记,为驾驶员提供重要信息
Pavement markings define separate lanes of traffic traveling in the same direction, inform drivers of lane restrictions, and convey certain regulation and warnings that would not otherwise be clearly understand.路面标记定义了单独的车道交通朝同一方向行驶,告诉驾驶员该车道限速,以及传达某些规则和警告,否则,它们不会被驾驶员清楚的明白。
Pavement markings are particularly important at night and during inclement weather, and,therefore, must be retroreflective.While well-maintained painted pavement markings are acceptable, thicker, long-life markings ,such as thermoplastic or performed tapes ,may perform better in wet weather and heavy traffic.同时保养好的涂有油漆的路面标志是可以采用的,厚的,长寿命的标记,像热塑性塑料或预成行的条带,可以在潮湿的空气和交通繁忙时表现得更出色。
Some studies have been made regarding the benefits of wider edge line markings(150 to 200 mm versus the standard 100 mm width).The wider markings may particularly benefit older drivers.一些研究已经取得了有关更宽边缘线方面的好处(150到200毫米相对于100毫米的标准宽度)。更宽的标记对老司机尤为有利。
第四篇:专业英语翻译
桩筏基础的简化设计方法
摘要:在筏板基础本身并不能满足设计要求情况下,可通过在筏板下增加桩来提高其承载力。合理的布置一定量的桩,可以提高桩筏基础的承载力和减少总沉降和差异沉降。本文分析了简化计算方法的过程,对桩筏基础的初步设计提供了有用的依据。它包括两个阶段:
1.桩筏基础整体性能的评价;
2.单柱荷载作用下的性能评价。
第五篇:专业英语翻译
8.Structural Steel Behaviour
土木0704乔荟07231104
静载下的力学性能 最重要的机械结构钢性能的静负荷是表示在理想化的拉伸应力应变Fig.8.1所示图。最初的刚才有一个线性的应力应变曲线的斜率是杨氏弹性模量。钢的弹性,同时保持在这个线性范围,完全恢复。该线弹性特性的限制,通常近似屈服应力约200000MPA,以及相应的范围内。超过这个限制塑性钢的流动没有任何压力,直到应变硬化应变的增加就达到了。这通常是塑料的范围相当大,以及对钢铁延性非常重视。
屈服应力或许是结构钢的最重要的强度特性,它随着钢材化学 不同发生显著的变化,最重要的成分是碳和锰,两者都会引起屈服应力的提高。屈服应力随着热处理方法和压制过程的工作量而变化,在同样的条件下压制次数多的薄板的屈服应力高于较厚的钢板。硬化也可以提高屈服应力,拉伸的速率影响屈服应力,高拉伸速率会提高前期屈服应力,也可以提高下屈服应力Fy.在试验中用到的用来确定特殊钢种屈服应力的拉伸速率比实际结构中经常遇到的几乎不变的速率要明显提高很多。根据设计目的,各个不同的钢级别要确定一个最小屈服应力,在澳大利亚和英格兰,是根据化学组成和热处理方法来分级的,而且各个级别的屈服应力随压制面最大厚度的增加而减小,另一方面,美国的惯例是在个级别内区分化学组成和热处理方法。所应用的屈服应力不随厚度而变化。每种钢材的最小屈服应力是根据一系列的标准拉伸试验的结果确定的。由于成分组成,热处理方法,压制次数,板厚和试验速率的小的变化,在这些试验结果中有种显著的分布,这种分布近似服从正态分布曲线。因此,某种钢材用在设计中的最小屈服应力通常是一个特征值,其在任何标准拉伸试验中会超过某个概率,因而一个独立的试验结果很可能明显高于我们引用的屈服应力。当然,这种区别会更明显的如果试验不再横截面最后的位置进行的话。通常认为,单向拉伸所确定的屈服应力对单向压缩也正确。
重复荷载下的疲劳破坏
结构钢经过多次的循环交变荷载后可能在低水平拉应力条件下发生破
坏。由重复荷载导致的局部损伤会引起这种高周疲劳破坏,它导致了微小裂缝的形成,疲劳裂缝的程度随着后来的重复荷载而逐渐增大,直到最终有效横截面积小以至发生突然破坏,高周疲劳只是当在结构物设计基准期可能出现大量的荷载循环时的一种设计的考虑。这通常是桥梁,起重机,和支撑机械的结构物的问题,而且风和波浪荷载也可能引起疲劳问题。显著影响疲劳强度的因素有荷载循环次数,荷载循环中的应力幅以及局部应力集中的大小。
通常,节点应当布置得使应力集中减少到最小,以使通过节点的‘应力流,尽可能平滑。
焊接细节也应考虑到这一决定,和不必要的'压力聚集者,应避免。它也将有利于限制,如可行,接头的地点,如在接近中性轴点,低应力区。
冲击荷载下的脆性破坏 结构钢不总表现出可塑的特性,在一些情况下可能发生突然破坏,即使名义拉应力很低。脆性破坏由局部高应力区域的微小裂缝的存在或形成而引发。一旦开始,裂纹就会稳定增长因为外力会提供撕裂钢材所需的能量。更严重的是快速不稳定传播的裂缝,因为储存在钢材中的固有的弹性应变能被释放并用来使钢材破坏。只要有足够的应变内能,这种裂缝是自扩展的并且将延伸至被扩展路径中的延性元件破裂。这种延性元件具有足够的变形能力吸收释放的内能。由于钢材的延性,在三向约束条件下,结构对脆性破坏的抵抗由局部应力集中的大小确定。高集中应力促进裂缝开展,所以由不良的几何形状和荷载布置引起的应力集中都很危险,而且材料的裂纹和缺陷也非常重要。不仅会增加局部应力而且有可能成为裂纹扩展区。结构钢的延性取决于钢材的组成,热处理方法和钢材的厚度,并且随温度和应变率的变化而变化。像发生在更厚或者更大颗粒元素的钢材中南,三向的几何约束也会促进脆性,这是因为有更高的局部应力,因为在开裂过程中的更大的能量释放和裂缝传播的减缓。
脆性破坏的危险可以由选择适合温度下延性的钢材类型来降低,或者通
过由减小应力集中和几何约束的观点来设计节点。装配技术应该尽量避免引进潜在的危险裂缝或缺陷。重要结构物的设计细节需要受目的在于探测严重缺陷的检查程序的影响。当然,设计者还必须适当考虑特种钢,制造技术,检测和修正程序的额外费用。
9.Earth Pressures
重力式传播的稳定条件
设计必须考虑的不是最终或使用极限状态,计算表明,必须有足够的经费是对发生不良极限状态有关一个特定类型的墙体了。在挡土墙的失效模式的数目可能对于检查外部稳定,重力墙被视为刚体(即没有内部收益或扭曲)。在某些类型的结构检验中,还需要有内部的稳定,例如钢筋混凝土墙,加固土墙。
上述给出的安全系数的运用是设计的传统方法,在1994年推荐的极限状态方法要求对强度代表值运用一个调节系数来获得设计值,例如,如果墙体位移量要求不超过0.5%的墙高,不排水强度下应用的M之应该小于1.5,承载能力计算时M应该在2到3之间,有效应力参数M应该小于1.2。结构内力和弯矩应该由设计土压力和水压力确定。为方便起见,重力墙壁取决于他们对外部的稳定和极限状态下自身的重量基本上应审查:力量作用在挡土墙中的垂直和水平分量计算。为了方便垂直力量包括墙壁的垂直载荷的重量和任何它可能携带,随土壤以上的L形和T形墙踵重量在一起。也可能是地球的压力造成的垂直分量的支持时,面对的不垂直,地面是倾斜的或在墙上摩擦是包括在内。
挡土墙的土压力
主动土压力对能够阻止土体塌落、滑移和蠕变为自然平衡状态的任何挡土结构施加水平向和竖直向荷载分量,这些结构在土压力的作用下会发生稍微的屈服。当挡土结构挤压墙后土体时,产生被动土压力。静止土压力是土
体施加给不屈服竖直挡土表面的水平压力。静止土压力表示介于主动和被动两种极限状态之间的情况。
每一种土压力都取决于土壤的物理特性以及土壤和结构的相对刚性。土最重要的性质看来是密度、砂土的内摩擦角、黏性土的黏聚力和超固结比。就任意土体材料来说,作用在常见挡土墙上的主动土压力水平分量可由针对墙背竖直、墙后填土面基本水平的一般土压力楔体理论很好地给出。
假定该墙体采用通常的施工方法进行回填,并且能够产生一小的转动(转动大小为0.001倍的墙体高度)引发回填土的内摩擦。该转角等价于土压力作用下20英尺墙体的上表面向外移动1/4英寸。
一般土压力楔体理论的公式(考虑了沿挡土墙墙面的摩擦)也可以用来计算墙体和填土面倾斜等其它所有情况下的水平分力。然而,和试验结果相比则表明计算结果对负超载情况有点偏小,对正超载情况有点偏大,但是相差不超过10%。如果考虑进关于实际坡度的条件的不确定性,将挡土墙简化为墙背垂直填土面水平的情况进行计算,也是足够精确的。
在所有情况下,侧向压力的竖直分量会使土压力合力与墙背的法线形成一个等于墙面摩擦角的角度。然而,该角度在任何情况下都不能超过墙后填土的内摩擦角。
有些土由于缺少排水及他们自身的性质,在任何情况下都可能变为流体(不管形成的流体材料是大面积的还是仅仅靠墙的一条窄层);这些土的压力和与其具有同样密度的流体的静水压力相等。
浸没土的压力可由式(9.1)给出,只不过式中采用的材料容重会由于水的浮力和浸没条件下的内摩擦系数而降低;除此之外,也必须包括完全的静水压力。对于粒状材料来说,水下的浸没对内摩擦系数和墙面摩擦系数的影响非常小。