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英文文献和中文翻译{RTP-实时软件传输协议}

RTP: A Transport Protocol for Real-Time Applications

1 Introduction

This memorandum specifies the real-time transport protocol (RTP), which provides end-to-end delivery services for data with real-time characteristics, such as interactive audio and video. Those services include payload type identification, sequence numbering, times tamping and delivery monitoring. Applications typically run RTP on top of UDP to make use of its multiplexing and checksum services; both protocols contribute parts of the transport protocol functionality. However, RTP may be used with other suitable underlying network or transport protocols (see Section 10). RTP supports data transfer to multiple destinations using multicast distribution if provided by the underlying network.

Note that RTP itself does not provide any mechanism to ensure timely delivery or provide other quality-of-service guarantees, but relies on lower-layer services to do so. It does not guarantee delivery or prevent out-of-order delivery, nor does it assume that the underlying network is reliable and delivers packets in sequence. The sequence numbers included in RTP allow the receiver to reconstruct the sender's packet sequence, but sequence numbers might also be used to determine the proper location of a packet, for example in video decoding, without necessarily decoding packets in sequence.

While RTP is primarily designed to satisfy the needs of multi- participant multimedia conferences, it is not limited to that particular application. Storage of continuous data, interactive distributed simulation, active badge, and control and measurement applications may also find RTP applicable.

This document defines RTP, consisting of two closely-linked parts:

[1].The real-time transport protocol (RTP), to carry data that has real-time properties.

[2]. The RTP control protocol (RTCP), to monitor the quality of service and to convey information about the participants in an on-going session. The latter aspect of RTCP may be sufficient for "loosely controlled" sessions, i.e., where there is no explicit membership control and set-up, but it is not necessarily intended to support all of an application's control communication requirements. This functionality may be fully or partially subsumed by a separate session control protocol, which is beyond the scope of this document.

RTP represents a new style of protocol following the principles of application level framing and integrated layer processing proposed by Clark and Tennenhouse [1]. That is, RTP is intended to be malleable to provide the information required by a particular application and will often be integrated into the application processing rather than being implemented as a separate layer. RTP is a protocol framework that is deliberately not complete. This document specifies those functions expected to be common across all the applications for which RTP would be appropriate. Unlike conventional protocols in which additional functions might be accommodated by making the protocol more general or by adding an option mechanism that would require parsing, RTP is intended to be tailored through modifications and/or additions to the headers as needed. Examples are given in Sections 5.3 and 6.3.3.

Therefore, in addition to this document, a complete specification of RTP for a particular application will require one or more

companion documents (see Section 12):

[1].A profile specification document, which defines a set of payload type codes and their mapping to payload formats (e.g., media encodings). A profile may also define extensions or modifications to RTP that are specific to a particular class of applications. Typically an application will operate under only one profile. A profile for audio and video data may be found in the companion RFC TBD.

[2].Payload format specification documents, which define how a particular payload, such as an audio or video encoding, is to be carried in RTP.

A discussion of real-time services and algorithms for their implementation as well as background discussion on some of the RTP design decisions can be found in [2].

Several RTP applications, both experimental and commercial, have already been implemented from draft specifications. These applications include audio and video tools along with diagnostic tools such as traffic monitors. Users of these tools number in the thousands. However, the current Internet cannot yet support the full potential demand for real-time services. High-bandwidth services using RTP, such as video, can potentially seriously degrade the quality of service of other network services. Thus, implementors should take appropriate precautions to limit accidental bandwidth usage. Application documentation should clearly outline the limitations and possible operational impact of high-bandwidth real- time services on the Internet and other network services.

2 RTP Use Scenarios

The following sections describe some aspects of the use of RTP. The examples were chosen to illustrate the basic operation of applications using RTP, not to limit what RTP may be used for. In these examples, RTP is carried on top of IP and UDP, and follows the conventions established by the profile for audio and video specified in the companion Internet-Draft draft-ietf-avt-profile

2.1 Simple Multicast Audio Conference

A working group of the IETF meets to discuss the latest protocol draft, using the IP multicast services of the Internet for voice communications. Through some allocation mechanism the working group chair obtains a multicast group address and pair of ports. One port is used for audio data, and the other is used for control (RTCP) packets. This address and port information is distributed to the intended participants. If privacy is desired, the data and control packets may be encrypted as specified in Section 9.1, in which case an encryption key must also be generated and distributed. The exact details of these allocation and distribution mechanisms are beyond the scope of RTP.

The audio conferencing application used by each conference participant sends audio data in small chunks of, say, 20 ms duration. Each chunk of audio data is preceded by an RTP header; RTP header and data are in turn contained in a UDP packet. The RTP header indicates what type of audio encoding (such as PCM, ADPCM or LPC) is contained in each packet so that senders can change the encoding during a conference, for example, to accommodate a new participant that is connected through a low-bandwidth link or react to indications of network congestion.

The Internet, like other packet networks, occasionally loses and

reorders packets and delays them by variable amounts of time. To cope with these impairments, the RTP header contains timing information and a sequence number that allow the receivers to reconstruct the timing produced by the source, so that in this example, chunks of audio are contiguously played out the speaker every 20 ms. This timing reconstruction is performed separately for each source of RTP packets in the conference. The sequence number can also be used by the receiver to estimate how many packets are being lost.

Since members of the working group join and leave during the conference, it is useful to know who is participating at any moment and how well they are receiving the audio data. For that purpose, each instance of the audio application in the conference periodically multicasts a reception report plus the name of its user on the RTCP (control) port. The reception report indicates how well the current speaker is being received and may be used to control adaptive encodings. In addition to the user name, other identifying information may also be included subject to control bandwidth limits. A site sends the RTCP BYE packet (Section 6.5) when it leaves the conference. 2.2 Audio and Video Conference

If both audio and video media are used in a conference, they are transmitted as separate RTP sessions RTCP packets are transmitted for each medium using two different UDP port pairs and/or multicast addresses. There is no direct coupling at the RTP level between the audio and video sessions, except that a user participating in both sessions should use the same distinguished (canonical) name in the RTCP packets for both so that the sessions can be associated.

One motivation for this separation is to allow some participants in the conference to receive only one medium if they choose. Further

explanation is given in Section 5.2. Despite the separation, synchronized playback of a source's audio and video can be achieved using timing information carried in the RTCP packets for both sessions.

2.3 Mixers and Translators

So far, we have assumed that all sites want to receive media data in the same format. However, this may not always be appropriate. Consider the case where participants in one area are connected through a low-speed link to the majority of the conference participants who enjoy high-speed network access. Instead of forcing everyone to use a lower-bandwidth, reduced-quality audio encoding, an RTP-level relay called a mixer may be placed near the low-bandwidth area. This mixer resynchronizes incoming audio packets to reconstruct the constant 20 ms spacing generated by the sender, mixes these reconstructed audio streams into a single stream, translates the audio encoding to a lower-bandwidth one and forwards the lower- bandwidth packet stream across the low-speed link. These packets might be unicast to a single recipient or multicast on a different address to multiple recipients. The RTP header includes a means for mixers to identify the sources that contributed to a mixed packet so that correct talker indication can be provided at the receivers.

Some of the intended participants in the audio conference may be connected with high bandwidth links but might not be directly reachable via IP multicast. For example, they might be behind an application-level firewall that will not let any IP packets pass. For these sites, mixing may not be necessary, in which case another type of RTP-level relay called a translator may be used. Two translators

are installed, one on either side of the firewall, with the outside one funneling all multicast packets received through a secure connection to the translator inside the firewall. The translator inside the firewall sends them again as multicast packets to a multicast group restricted to the site's internal network.

Mixers and translators may be designed for a variety of purposes. An example is a video mixer that scales the images of individual people in separate video streams and composites them into one video stream to simulate a group scene. Other examples of translation include the connection of a group of hosts speaking only IP/UDP to a group of hosts that understand only ST-II, or the packet-by-packet encoding translation of video streams from individual sources without resynchronization or mixing. Details of the operation of mixers and translators are given in Section 7.

中文翻译

RTP-----------实时软件传输协议

1 介绍

实时传输协议RTP，可以对于那些具有实时特征的数据，比如交互式的音频、视频提供端到端的传输服务。提供的服务包括对传输数据类型的鉴别，顺序的排列以及传输时间及过程的监控。一般应用程序运行RTP多与UDP来实现多路传输和checksum的服务，虽然两种协议都提供了传输功能，但是RTP 可以用在某些与之相适配的底层网络和传输协议中。RTP可以在网络的允许下利用多点传送功能向多个目标发送数据。

但是要注意到，RTP本身不能对传输的及时性及传输的质量提供保证，这些是依靠它的下层服务来实现的。它也不能保证在传输过程中传输顺序都是有序的，就像他不能确定基层的网络是可靠的，其在网络上传送的包是按顺序的一样。RTP中对包都进行了编号，那样就允许接受者重建包的顺序，而且这些编码可以用来测定包所在的位子，比如一个视频，完全依次进行编码是没有必要的。

RTP最初设计是为了满足多人视频会议，但现在已经不仅仅局限在这个方面了，数据的连续存储，互动的分布式模拟，以及控制和测量部门都能找RTP的身影。

本文对RTP的定义包括两个方面：

[1].实时传输协议，用来传输具有实时特征的数据；

[2].实施传输控制协议RTCP，用来监测服务的质量以及传达某个正在进行的会议中各个成员的信息。对于RTCP第二个方面的应用，在一些不是非常严格的会议我们已经得到了应用：一般这些会议没有复杂的成员控制和建立，那么对所有应用程序控制的交流是没有必要的。这种情况也许会被部分或者全部的包含在一个独立的会议控制中，这个已经超出了本文的讨论范围。

RTP是继应用层框架原理以后新的协议类型，他整合层的处理。也就是说RTP对于一个应用程序所要求得信息处理已经不再

是作为一个单独的层去进行，而是随着整合进该程序的进行过程中，同时处理。RTP有意成为一个不完整的协议框架。本文阐述这些功能，希望在那些适合RTP的应用程序中RTP能得到充分的发挥。而不像一些传统的协议那样，需要通过推广或者是机构的授权来增加附加功能。此外，如果想要知道对于某一个特定程序的RTP的描述，你可以在一些相关的书中寻找（见12章）：[1].一个概括地说明文档，定义一系列载荷类型编码和相对应的载荷格式。同时也说明了在某些特定的类型的应用程序中RTP的扩展和修改。以及各一个具有代表性的应用程序的炒作过程。一个为视频和音频数据做的概要说明可以在RFC TBD里找到。[2].在和类型的描述文档，定义了一个特定的载荷，比如音频和视频编码是如何通过RTP来传输的。

对于实时服务的讨论，对于RTP设计及其运行时所遵循的算法和背景的讨论我们可以在第二节找到。

一些RTP程序，不管是试验性质的还是商业性质的从设计阶段上升到了实践阶段。这些程序包括音频和视频工具以及一些诊断工具比如交通监视器。这些工具的用户数量已有成千上万。但是现在的英特网还无法支持实时服务全部潜在的需求，利用RTP 的高速宽带服务，比如视频，将会严重的降低网络其他服务的质量。所以，执行者应该采取合适的防范措施来限制那些次要的宽带利用。应用程序文件会清楚的略述这些限制以及在英特网和其他网络服务中高速宽带的实时服务可能会带来的影响。

2 RTP 使用环境

这个章节我们将讨论RTP的使用方面。我们将会通过实例来说明使用RTP程序的一些基本操作，但不限制使用的是什么样的RTP。在这些举例中，RTP运载于IP和UDP之上，在其之后是

一些为了视频和音频而已经确立的协议，这些协议可以在同类书籍中找到。

2.1 简单的多点音频会议

一个工作组要讨论一个最近的工作草案，他们可以通过英特网的多点服务来进行语音交流。通过一些机制分配，工作组组长获得一个多点传送的地址以及两个端口，一个是用来传输语音数据，一个是用来控制包的传输，这个地址同时也被分送到每个成员那里。如果有保密的需要，数据及控制包可以被加密（详见9.1章），当然这样的话解密钥匙也必须要发布出去，关于机制的具体分布与安排不在RTP的讨论范围之内。

参加音频会议的人以包的形式传输语音数据，平均20毫秒一个。每个包有一个RTP报头。RTP 报头及其数据依次放入UDP包中。RTP报头用来说音频编码的类型（比如PCM ,ADPCM, LPC）,这样的方式可以让数据发送者在会议中改变编码方式，这样的话，我们可以单独的为一个低速会议成员安排接入方式，同时我们也可以对网络的拥堵做出反应。

英特网，和其他的封宝试的网络一样，有时候会丢失包或者发生不可预知的时间延迟，为了处理这种情况，RTP报头包含了一个时间信息，和一个序列号码，那样就允许接受者重新排序，在这个例子中，音频包每隔20毫秒发出一个，会议中对于这些RTP包时序的重组一直在独立的进行着。序列号码还可以用来估计有多少包在传输中丢失了。

鉴于工作组成员会在开会时进入或者离开，那么清楚的知道到底谁在参加会议以及到底他们接受的音频数据质量如何是很有用的。于是每一个远程应用程序会定时的往RTCP发送一个接收报告，报告里会附上他们的名字。这个报告会指出现在对于讲话者数据接收如何从而用来控制合适的编码。除了用户的名字之外，

我们还会用到其他的鉴别信息来控制款待限制。一个节点会发送一个“BYE”包（见6.5章）当他离开的时候。

2.2音频和视频会议

如果在一个会议中同时要用到视频和音频的话，他们在传输的过程中，用的是互相独立的RTP层，两种媒体的RTCP包也是用不同的UDP端口或者是不同的多点传送地址。

在音频和视频两个层之间没有直接的连接。除非是一个成员要以同一个规范化的名字参加两个会议层，这种情况下连个层会被连在一起。

把两种媒体分割开来可以使会议成员自由的选择一种或两种媒体。尽管是分割的，但是通过RTCP包中的时间信息，我们完全可以是两种媒体同步起来。

2.3混频和翻译

到目前为止，我们一直假定所有的网站都是接受相同类型的媒体数据，但事实上，这种假定是不合理的。考虑到有些成员，以低速网络接入一个大部分成员是高速网络的会议中，我们可以在低速网络的区域放一个混频器那样我们就不用要求每一个成员都要以低速，低质的音频方式接入了。这个混频器重新同步音频包，以恒定的20毫秒的间隔重建发送者的音频信号。把这些改造过的音频流混合成一个单独的流，这样就把这些音频编码转化成了适用于低速宽带面下低速连接的数据包流。这些包可以被断点传送给一个用户也可以被多点传送给不同用户的不同地址。RTP 报头包含了混合器的方法，这样即使包被混合了，接受者还是可以正确的确认谁在发言。

音频会议中，一些用户虽然是通过高速宽带连接，但他们有可能依然不可以直接通过IP被多点传送。比如，他们运行了一个应用层的防火墙，就会阻止任何IP包通过。对于这些站点，混频

可能会失败，这种情况下我们可以利用另一个方法,翻译。防火墙的两端都装上翻译器，这样防火墙的两端好像形成了一个相连的漏斗，多点传送包，就可以安全的从外面传到里面，然后防火墙内部的翻译器再一次对网络内部进行多点传送。

关于力的外文文献翻译、中英文翻译、外文翻译

五、外文资料翻译 Stress and Strain 1.Introduction to Mechanics of Materials Mechanics of materials is a branch of applied mechanics that deals with the behavior of solid bodies subjected to various types of loading. It is a field of study that i s known by a variety of names, including “strength of materials” and “mechanics of deformable bodies”. The solid bodies considered in this book include axially-loaded bars, shafts, beams, and columns, as well as structures that are assemblies of these components. Usually the objective of our analysis will be the determination of the stresses, strains, and deformations produced by the loads; if these quantities can be found for all values of load up to the failure load, then we will have obtained a complete picture of the mechanics behavior of the body. Theoretical analyses and experimental results have equally important roles in the study of mechanics of materials . On many occasion we will make logical derivations to obtain formulas and equations for predicting mechanics behavior, but at the same time we must recognize that these formulas cannot be used in a realistic way unless certain properties of the been made in the laboratory. Also , many problems of importance in engineering cannot be handled efficiently by theoretical means, and experimental measurements become a practical necessity. The historical development of mechanics of materials is a fascinating blend of both theory and experiment, with experiments pointing the way to useful results in some instances and with theory doing so in others①. Such famous men as Leonardo da Vinci(1452-1519) and Galileo Galilei (1564-1642) made experiments to adequate to determine the strength of wires , bars , and beams , although they did not develop any adequate theo ries (by today’s standards ) to explain their test results . By contrast , the famous mathematician Leonhard Euler(1707-1783) developed the mathematical theory any of columns and calculated the critical load of a column in 1744 , long before any experimental evidence existed to show the significance of his results ②. Thus , Euler’s theoretical results remained unused for many years, although today they form the basis of column theory. The importance of combining theoretical derivations with experimentally determined properties of materials will be evident theoretical derivations with experimentally determined properties of materials will be evident as we proceed with

七年级下册英语短文带中文翻译(1-12单元)

Unit 1 (sectionB 3a) Dear Student, My name is Bob . I live in Toronto , Canada , and I want a pen pal in China . I think China is a interesting country . I’m 14 years old and my brithday is in November . I can sperk English and a littie Frenth . I have a brother , Paul , and a sister , Sarah . They have pen pals in the United Kingdom and Australia . I like going to the movies with my friends and playing sports . My favorite subject in school is P.E . It’s fun . But I don’t like math. It’s too difficult! Can you wtite to me soon? Bob 亲爱的同学，我的名字叫鲍勃，我住在加拿大的多伦多。我想在中国找个笔友。我认为中国是个非常有趣的国家。我十四岁，我的生日在九月。我能说英语和一点法语。我有一个哥哥 Paul, 和一个姐姐Sarah。他们在英国和澳大利亚有笔友。我喜欢和我的朋友们看电影和做运动。在学校我最喜欢的科目是体育。它很有趣。但我不喜欢数学。它太难了。你能尽快给我写信吗 Bob 3b PEN PAL WANTED My name is Tom King . I’m 14 years old and I’m from Australia . I sperk English . I have a brother , Sam , and a sister , Lisa . I play soccer on weekengs . It’s my favorite sport . I like music at school . It’s fun! My favorite movte is The Long Weekend . Do you know it ? It’s an action movie . Please write and tell me about yoursrlf. 征集笔友我的名字是汤姆~金。我14岁,我来自澳大利亚。我讲英语。我有一个哥哥, 萨姆,和一个妹妹,莉莎。我在周末踢足球，那是我最喜欢的运动。我喜欢学校的音乐课。它是有趣的!我最喜欢的电影是《这个长周末》。你知道它吗?它是一部动作片。请写信给我,告诉我有关你的一些情况。 Unit 2 (sectionB 3a) Welcome to the Garden District Turn left on First Avenue and enjoy the city’s quiet streets and smail parks . Take a walk through the park on Center Avenue . Across from the park is an old hotel . Next to the hotel is a small house with an interesting garden . This is the benginning of the garden tour. 欢迎来到这个花园区在第一大街左转并享受这个城市的安静街道和小公园。在中心大道上散步穿过这个公园。在公园对面是一个老旅馆。紧靠这个旅馆旁边是一个带着有趣花园的小房子。开始游历这个花园。

平面设计中英文对照外文翻译文献

(文档含英文原文和中文翻译) 中英文翻译平面设计任何时期平面设计可以参照一些艺术和专业学科侧重于视觉传达和介绍。采用多种方式相结合，创造和符号，图像和语句创建一个代表性的想法和信息。平面设计师可以使用印刷，视觉艺术和排版技术产生的最终结果。平面设计常常提到的进程，其中沟通是创造和产品设计。共同使用的平面设计包括杂志，广告，产品包装和网页设计。例如，可能包括产品包装的标志或其他艺术作品，举办文字和纯粹的设计元素，如形状和颜色统一件。组成的一个最重要的特点，尤其是平面设计在使用前现有材料或不同的元素。平面设计涵盖了人类历史上诸多领域，在此漫长的历史和在相对最近爆炸视觉传达中的第20和21世纪，人们有时是模糊的区别和重叠的广告艺术，平面设计和美术。毕竟，他们有着许多相同的内容，理论，原则，做法和语言，有时同样的客人或客户。广告艺术的最终目标是出售的商品和服务。在平面

设计，“其实质是使以信息，形成以思想，言论和感觉的经验”。在唐朝（ 618-906 ）之间的第4和第7世纪的木块被切断打印纺织品和后重现佛典。阿藏印在868是已知最早的印刷书籍。在19世纪后期欧洲，尤其是在英国，平面设计开始以独立的运动从美术中分离出来。蒙德里安称为父亲的图形设计。他是一个很好的艺术家，但是他在现代广告中利用现代电网系统在广告、印刷和网络布局网格。于1849年，在大不列颠亨利科尔成为的主要力量之一在设计教育界，该国政府通告设计在杂志设计和制造的重要性。他组织了大型的展览作为庆祝现代工业技术和维多利亚式的设计。从1892年至1896年威廉?莫里斯凯尔姆斯科特出版社出版的书籍的一些最重要的平面设计产品和工艺美术运动，并提出了一个非常赚钱的商机就是出版伟大文本论的图书并以高价出售给富人。莫里斯证明了市场的存在使平面设计在他们自己拥有的权利，并帮助开拓者从生产和美术分离设计。这历史相对论是，然而，重要的，因为它为第一次重大的反应对于十九世纪的陈旧的平面设计。莫里斯的工作，以及与其他私营新闻运动，直接影响新艺术风格和间接负责20世纪初非专业性平面设计的事态发展。谁创造了最初的“平面设计”似乎存在争议。这被归因于英国的设计师和大学教授Richard Guyatt，但另一消息来源于20世纪初美国图书设计师William Addison Dwiggins。伦敦地铁的标志设计是爱德华约翰斯顿于1916年设计的一个经典的现代而且使用了系统字体设计。在20世纪20年代，苏联的建构主义应用于“智能生产”在不同领域的生产。个性化的运动艺术在俄罗斯大革命是没有价值的，从而走向以创造物体的功利为目的。他们设计的建筑、剧院集、海报、面料、服装、家具、徽标、菜单等。 Jan Tschichold 在他的1928年书中编纂了新的现代印刷原则，他后来否认他在这本书的法西斯主义哲学主张，但它仍然是非常有影响力。 Tschichold ，包豪斯印刷专家如赫伯特拜耳和拉斯洛莫霍伊一纳吉，和El Lissitzky 是平面设计之父都被我们今天所知。他们首创的生产技术和文体设备，主要用于整个二十世纪。随后的几年看到平面设计在现代风格获得广泛的接受和应用。第二次世界大战结束后，美国经济的建立更需要平面设计，主要是广告和包装等。移居国外的德国包豪斯设计学院于1937年到芝加哥带来了“大规模生产”极简到美国;引发野火的“现代”建筑和设计。值得注意的名称世纪中叶现代设计包括阿德里安Frutiger ，设计师和Frutiger字体大学;保兰德，从20世纪30年代后期，直到他去世于1996年，采取的原则和适用包豪斯他们受欢迎的广告和标志设计，帮助创造一个独特的办法，美国的欧洲简约而成为一个主要的先驱。平面设计称为企业形象;约瑟夫米勒，罗克曼，设计的海报严重尚未获取1950年代和1960年代时代典型。从道路标志到技术图表，从备忘录到参考手册，增强了平面设计的知识转让。可读性增强了文字的视觉效果。设计还可以通过理念或有效的视觉传播帮助销售产品。将它应用到产品和公司识别系统的要素像标志、颜色和文字。连同这些被定义为品牌。品牌已日益成为重要的提供的服务范围，许多平面设计师，企业形象和条件往往是同时交替使用。

英语背诵美文30篇(翻译)

生而为赢（中文翻译） ——新东方英语背诵美文30篇目录： ·第一篇：Y outh 青春 ·第二篇：Three Days to See(Excerpts)假如给我三天光明（节选） ·第三篇：Companionship of Books 以书为伴（节选） ·第四篇：If I Rest, I Rust 如果我休息，我就会生锈 ·第五篇：Ambition 抱负 ·第六篇：What I have Lived for 我为何而生 ·第七篇：When Love Beckons Y ou 爱的召唤 ·第八篇：The Road to Success 成功之道 ·第九篇：On Meeting the Celebrated 论见名人 ·第十篇：The 50-Percent Theory of Life 生活理论半对半 ·第十一篇What is Y our Recovery Rate? 你的恢复速率是多少？ ·第十二篇：Clear Y our Mental Space 清理心灵的空间 ·第十三篇：Be Happy 快乐 ·第十四篇：The Goodness of life 生命的美好 ·第十五篇：Facing the Enemies Within 直面内在的敌人 ·第十六篇：Abundance is a Life Style 富足的生活方式 ·第十七篇：Human Life a Poem 人生如诗 ·第十八篇：Solitude 独处 ·第十九篇：Giving Life Meaning 给生命以意义 ·第二十篇：Relish the Moment 品位现在 ·第二十一篇：The Love of Beauty 爱美 ·第二十二篇：The Happy Door 快乐之门 ·第二十三篇：Born to Win 生而为赢 ·第二十四篇：W ork and Pleasure 工作和娱乐 ·第二十五篇：Mirror, Mirror--What do I see镜子,镜子,告诉我 ·第二十六篇：On Motes and Beams 微尘与栋梁 ·第二十七篇：An October Sunrise 十月的日出 ·第二十八篇：To Be or Not to Be 生存还是毁灭 ·第二十九篇：Gettysburg Address 葛底斯堡演说 ·第三十篇：First Inaugural Address(Excerpts) 就职演讲（节选） 1．青春-------------------------------------------------------------------------- 青春不是人生的一个阶段，而是一种心境；青春不是指粉红的面颊、鲜艳的嘴唇、富有弹性的膝盖，而是指坚定的意志、丰富的想象、充沛的情感；青春，它是清新的生命之泉。青春是一种气质，勇敢胜过怯弱，渴求冒险而不贪图安逸。这样的气息60老者常常有，20青年恰恰无。年岁增添，未必使人垂老；理想不再，终于步入暮年。岁月悠悠，衰微只及肌肤；热忱抛却，颓废必致灵魂。忧烦、惶恐、自卑，使人心灵扭曲，心灰意冷。无论60还是16岁，人人心中都怀着对新奇事物的向往，象孩童般对未来充满憧憬，此情永不消退，在生活的游戏中汲取快乐。在你我的内心深处都有一座无线电台，只要它接收到人间和上帝发出的美好、希望、欢乐、勇气和力量的信号，你就会青春永驻。

10kV小区供配电英文文献及中文翻译

在广州甚至广东的住宅小区电气设计中,一般都会涉及到小区的高低压供配电系统的设计.如10kV高压配电系统图,低压配电系统图等等图纸一大堆.然而在真正实施过程中,供电部门(尤其是供电公司指定的所谓电力设计小公司)根本将这些图纸作为一回事,按其电脑里原有的电子档图纸将数据稍作改动以及断路器按其所好换个厂家名称便美其名曰设计(可笑不?),拿出来的图纸根本无法满足电气设计的设计意图,致使严重存在以下问题:(也不知道是职业道德问题还是根本一窍不通) 1.跟原设计的电气系统货不对板,存在与低压开关柜后出线回路严重冲突,对实际施工造成严重阻碍,经常要求设计单位改动原有电气系统图才能满足它的要求(垄断的没话说). 2.对消防负荷和非消防负荷的供电(主要在高层建筑里)应严格分回路(从母线段)都不清楚,将消防负荷和非消防负荷按一个回路出线(尤其是将电梯和消防电梯,地下室的动力合在一起等等,有的甚至将楼顶消防风机和梯间照明合在一个回路,以一个表计量). 3.系统接地保护接地型式由原设计的TN-S系统竟曲解成"TN-S-C-S"系统(室内的还需要做TN-C,好玩吧?),严格的按照所谓的"三相四线制"再做重复接地来实施,导致后续施工中存在重复浪费资源以及安全隐患等等问题.. ............................(违反建筑电气设计规范等等问题实在不好意思一一例举,给那帮人留点混饭吃的面子算了) 总之吧,在通过图纸审查后的电气设计图纸在这帮人的眼里根本不知何物,经常是完工后的高低压供配电系统已是面目全非了,能有百分之五十的保留已经是谢天谢地了. 所以.我觉得:住宅建筑电气设计,让供电部门走!大不了留点位置,让他供几个必需回路的电,爱怎么折腾让他自个怎么折腾去.. Guangzhou, Guangdong, even in the electrical design of residential quarters, generally involving high-low cell power supply system design. 10kV power distribution systems, such as maps, drawings, etc. low-voltage distribution system map a lot. But in the real implementation of the process, the power sector (especially the so-called power supply design company appointed a small company) did these drawings for one thing, according to computer drawings of the original electronic file data to make a little change, and circuit breakers by their the name of another manufacturer will be sounding good design (ridiculously?), drawing out the design simply can not meet the electrical design intent, resulting in a serious following problems: (do not know or not know nothing about ethical issues) 1. With the original design of the electrical system not meeting board, the existence and low voltage switchgear circuit after qualifying serious conflicts seriously hinder the actual construction, often require changes to the original design unit plans to meet its electrical system requirements (monopoly impress ). 2. On the fire load and fire load of non-supply (mainly in high-rise building in) should be strictly sub-loop (from the bus segment) are not clear, the fire load and fire load of non-qualifying press of a circuit (especially the elevator and fire elevator, basement, etc.

英文文献及中文翻译

毕业设计说明书英文文献及中文翻译学院：专 2011年6月电子与计算机科学技术软件工程

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英语短文中英文翻译

my friend and I are taking a , we are seeing a boy sit on the chair,he is crying,we go and ask him.“what’s the matter with you” he tell us“I can’t find my dog can you help me”.“yes,I can”.And we help him find his dong .oh it stay under the big tree! 今天我和我的朋友一起去散步。突然我们看见一个男孩坐在椅子上，他哭的很伤心。我们走过去问他：“你怎么了”。他告诉我们：“我的狗不见了，你们能帮我找到它吗”。“是的，我们能帮你找到你的狗”然后我们帮助他找到了他的狗，原来是它呆在一棵大树下。 day an old man siselling a big young man comes to the elephant and begins to look at it old man goes up to him and says inhis ear,“Don't sa y anything about the elephant before I sell it,then i'll give you some money.”“All right,”says the young the old man slles the elephant,he gives the young man some money and says,“Now,can you tell me how you find the bad ears of theelephant?”“I don't find the bad ears,”says the young man.“Then why do you look at the elephant slowly?”asks the old young man answers,“Because I never see an elephant before,and I want to know what it looks like.” 一天，一个老的男人正在卖一头大象。一个年轻的男人走向大象然后开始慢慢看着它（大象），这个老的男人走向他对着他的耳朵说，“不要在我卖出它（大象）之前说关于它（大象）的事，然后我会给你一些钱。”“好的”，这个年轻的男人说。在这个老的男人卖出大象后，他给了年轻的男人一些钱并且说，“现在，你可以告诉我你是怎样知道大象的坏的耳朵了吧？”“我不知道坏的耳朵”，这个年轻的男人说。“然后为什么你慢慢的看着大象？”这个老的男人问。这个年轻的男人回答，“因为我在这之前从来没有见过大象，还有我想知道它（大象）是什么样子的。” 3.An old woman had a cat. The cat was very old; she could not run quickly, and she could not bite, because she was so old. One day the old cat saw a mouse; she jumped and caught the mouse. But she could not bite it; so the mouse got out of her mouth and ran away, because the cat could not bite it.? Then the old woman became very angry because the cat had not killed the mouse. She began to hit the cat. The cat said, "Do not hit your old servant. I have worked for you for many years, and I would work for you still, but I am too old. Do not be unkind to the old, but remember what good work the old did when they were young."? 一位老妇有只猫，这只猫很老，它跑不快了，也咬不了东西，因为它年纪太大了。一天，老猫发现一只老鼠，它跳过去抓这只老鼠，然而，它咬不住这只老鼠。因此，老鼠从它的嘴边溜掉了，因为老猫咬不了它。? 于是，老妇很生气，因为老猫没有把老鼠咬死。她开始打这只猫，猫说：“不要打你的老仆人，我已经为你服务了很多年，而且还愿意为你效劳，但是，我实在太老了，对年纪大的不

英文论文及中文翻译

International Journal of Minerals, Metallurgy and Materials Volume 17, Number 4, August 2010, Page 500 DOI: 10.1007/s12613-010-0348-y Corresponding author: Zhuan Li E-mail: li_zhuan@https://www.sodocs.net/doc/68809075.html, ? University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2010 Preparation and properties of C/C-SiC brake composites fabricated by warm compacted-in situ reaction Zhuan Li, Peng Xiao, and Xiang Xiong State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China (Received: 12 August 2009; revised: 28 August 2009; accepted: 2 September 2009) Abstract: Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) were fabricated by the warm compacted-in situ reaction. The microstructure, mechanical properties, tribological properties, and wear mechanism of C/C-SiC composites at different brake speeds were investigated. The results indicate that the composites are composed of 58wt% C, 37wt% SiC, and 5wt% Si. The density and open porosity are 2.0 g·cm–3 and 10%, respectively. The C/C-SiC brake composites exhibit good mechanical properties. The flexural strength can reach up to 160 MPa, and the impact strength can reach 2.5 kJ·m–2. The C/C-SiC brake composites show excellent tribological performances. The friction coefficient is between 0.57 and 0.67 at the brake speeds from 8 to 24 m·s?1. The brake is stable, and the wear rate is less than 2.02×10?6 cm3·J?1. These results show that the C/C-SiC brake composites are the promising candidates for advanced brake and clutch systems. Keywords: C/C-SiC; ceramic matrix composites; tribological properties; microstructure [This work was financially supported by the National High-Tech Research and Development Program of China (No.2006AA03Z560) and the Graduate Degree Thesis Innovation Foundation of Central South University (No.2008yb019).] 温压-原位反应法制备C / C-SiC刹车复合材料的工艺和性能李专，肖鹏，熊翔粉末冶金国家重点实验室，中南大学，湖南长沙410083，中国（收稿日期：2009年8月12日修订：2009年8月28日;接受日期：2009年9月2日）摘要：采用温压?原位反应法制备炭纤维增强炭和碳化硅双基体(C/C-SiC)复合材

唯美的中文翻译成英文

唯美的中文翻译成英文 Abandon 放弃 Disguise 伪装 Abiding 持久的，不变的~friendship Indifferent 无所谓 Forever 最爱 I know what you want 我知道你想要什么 See you forget the breathe 看见你忘了呼吸 Destiny takes a hand.命中注定 anyway 不管怎样 sunflower high-profile向日葵，高姿态。 look like love 看起来像爱 Holding my hand, eyes closed you would not get lost 牵着我的手，闭着眼睛走你也不会迷路 If one day the world betrayed you, at least I betray the world for you! 假如有一天世界背叛了你，至少还有我为你背叛这个世界! This was spoiled child, do not know the heart hurts, naive cruel. 这样被宠惯了的小孩子，不知道人心是会伤的，天真的残忍。

How I want to see you, have a look you changed recently, no longer said once, just greetings, said one to you, just say the word, long time no see. 我多么想和你见一面，看看你最近的改变，不再去说从前，只是寒暄，对你说一句，只说这一句，好久不见。 In fact, not wine, but when the thought of drinking the unbearable past. 其实酒不醉人，只是在喝的时候想起了那不堪的过去。 The wind does not know clouds drift, day not know rain down, eyes do not understand the tears of weakness, so you don't know me 风不懂云的漂泊，天不懂雨的落魄，眼不懂泪的懦弱，所以你不懂我 Some people a lifetime to deceive people, but some people a lifetime to cheat a person 有些人一辈子都在骗人，而有些人用一辈子去骗一个人 Alone and lonely, is always better than sad together 独自寂寞，总好过一起悲伤 You are my one city, one day, you go, my city, also fell 你是我的一座城，有一天，你离开了，我的城，也就倒了。

中英文翻译与文献

Monolithic integrated circuit history The monolithic integrated circuit was born in the late-1970s, has experienced SCM, MCU, the SOC three big stages. SCM namely monolithic microcomputer (Single Chip Microcomputer) the stage, mainly seeks the best monolithic shape embedded system's best architecture. “the innovation pattern” obtains successfully, has established SCM and the general-purpose calculator completely different development path. In founds on the embedded system independent development path, Intel Corporation has lasting achievements. MCU namely micro controller (Micro Controller Unit) the stage, the main technological development direction is: Expands unceasingly when satisfies the embedded application, the object system request's each kind of peripheral circuit and the interface circuit, underline its object intellectualization control. It involves the domain is related with the object system, therefore, develops the MCU heavy responsibility to fall inevitably on electrical, the electronic technology factory. Looking from this angle, Intel fades out the MCU development also to have its objective factor gradually. Is developing the MCU aspect, the most famous factory family belongings count Philips Corporation. Philips Corporation by it in embedded application aspect huge superiority, MCS-51 from monolithic microcomputer rapidly expand to micro controller. Therefore, when we review the embedded system development path, do not forget Intel and the Philips historical merit. Monolithic integrated circuit is the embedded system's road of independent development, to the MCU stage development's important attribute, seeks application system's on chip maximized solution;