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对于圆检测，许多研究人员已经研究出使用改性羟色胺的方法分解参数和/或圆的一些几何性质，以减少复杂性。元朗等。 （1990年）已经进行了几羟色胺为基础的循环寻找技术的比较研究。参数分解为基础的方法通常是先从对检测中心的圆圈，然后确定半径。这些属性之一是正常的一个点上一圆通过圆（戴维斯，1987A的;伊林沃思和Kittler，1987）的中心通行证。业等。 （1992年）所使用的财产上的两个圆的切线平行是圆的直径的端点点。上述方法需要的边缘轮廓对噪声非常敏感（戴维斯，1987年b）梯度信息。关于边缘的方向等信息噪音é€一般大于边缘位置。有没有使用边缘方向信息的几种途径。陈和小（1990）提出了基于快速椭圆检测的水平和垂直平分弦。同样，何和陈（1995）提出了一种快速检测算法界使用一个全局的几何对称性。它计算出来的对称轴和垂直轴对称水平圆心。许等人。 （1997年），用于在整个过程中，信息对称轴计算所有五个参数。 Goneid等。 （1997年）制定的和弦二分法使用一维数组。戴维斯（1999）研究了椭圆形的快速精确定位的简单和弦二分法。约安努等人的方法。 （1999年）已在该行的财产垂直平分一圆的弦穿过其中心的基础。雷和黄（1999）检测，发现对称轴的交点的两个中心是正交轴对候选人。其缺点是图像中的直线可以使检测复杂的对称轴。
什么意思没完全看懂，翻译你就看看吧Detection algorithm and initial laboratory results using V-BLAST space-time communication architecture . Golden, . Foschini, . Valenzuela . Wolniansky 和最初的实验室检测算法 结果运用V-BLAST时空 通讯构架 .金、蔡雯君、Foschini,. Valenzuela和 . WolnianskyELECTRONICS LETTERS 7th January 1999 Vol. 35 No. I 新年第一篇 1999年1月7日第35号。Detection algorithm and initial laboratory results using V-BLAST space-time communication architecture 最初的实验室检测算法和V-BLAST结果运用时空 通讯构架作者.金、蔡雯君、Foschini Valenzuela,.
本翻译符合专业要求，请明鉴，不过赏分有点少了。Spatial Compressive Sensing Approach For FieldDirectionality Estimation.用于场方向性估计的空间压缩传感方法I. INTRODUCTION1. 引言Variety of techniques for field directionality estimation werestudied in literature [1]-[5]. Thus, a theoretical analysis ofthe relationship between the hydrophone array output and thenoise field was conducted in [1]-[5]. 用于场方向性估计的多种技术在文献中做了研究[1]-[5]。因此，对水听器阵列输出和噪声场之间的关系进行了理论的分析[1]-[5]。The developed techniques were based on the array beamformer output or the cross spectralmatrix between outputs of array elements [4]-[5]. 所开发的技术是基于阵列波束形成器的输出或阵列单元输出之间的互功率谱矩阵[4]-[5]。The problem of a field directionality estimation in ocean, using horizontal line towed array was also addressed in literature [5]-[8]. 用水平线拖曳阵列在海洋中的场方向性估计问题，在文献中也用水平线拖曳阵列着重做了研究[5]-[8]。Recently, problems of direction of arrival and field directionalityestimation for moving sensors arrays have attractedrenewed interest [9]-[12]. 近年来，移动的传感器阵列的到达方向问题和场方向性估计问题已重新引起人们的兴趣[9]-[12]。It was shown that an array motioncan improve an array performance assuming temporal coherenceof successive samples [10]-[11]. 已经证明，假设相继的样本的时间相干性，那么一个阵列的运动可以改善一个阵列的性能[10]-[11]。In [12], the wavefieldsampling method that exploits the linear relationship betweenthe noise field and the collection of beamformer outputs overvarious array orientations was proposed.在文献[12]中，提出了探索噪声场和在各个不同阵列取向上采集波束形成器输出之间线性关系的波场取样方法。 It was shown thatthe wavefield sampling (WS) method outperforms other tested methods. This algorithm was implemented via the recursive estimation method and its convergence to the unique solution was promised for a specific set of array orientations and beamformer look directions. 已经证明，波长取样方法（WS）胜过其他被试验的方法。这一算法通过递推估计法实施，并且它对唯一解的收敛有望用于一组特定阵列取向和波束形成器观察方向。However, a method for a proper array orientation and beamformer look direction sequence selection remains an open question. 然而，一种用于完美阵列取向和波束形成器观察方向顺序选择的方法仍然是一个公开的问题。The quality of the field directionality estimation is determined by the angular resolution. The higher angular resolution is, the more accurate estimation of the far field sources,and better detection performance can be achieved. 场方向性估计的质量由角度分辨率决定。角度分辨率越高，远场源的估计精度就越高，并能达到越好的检测性能。One offundamental relations in the array signal processing is that the angular resolution is directly proportional to the number of the array elements [13]. 在阵列信号处理中的基本关系之一就是角度分辨率与阵列元件数成正比[13]。This relation motivates the desirefor longer arrays that can achieve higher resolution. Unfortunately,the requirement contradicts the implementation and installation limitations that motivate shorter arrays. 这一关系激发了采用能达到较高分辨率的较长阵列的欲望。不幸的是，这一要求与促进较短阵列的实施和敷设是矛盾的。Moreover, implementation of longer arrays for maneuvering platforms such as unmanned underwater vehicles (UUV) can even beimpossible [14]. 而且，对操纵平台（例如无人潜水器（UUV））实施较长阵列甚至会是不可能的[14]。These contradictions motivate the quest for alternative array signal processing methods. Usually, the field directionality is modeled as a finite set of strong far-field narrow-band sources and an isotropic lowpower noise [1]. 这些矛盾激发了人们对可供选择的阵列信号处理方法的寻找。通常，场方向性被建模为一组有限的强远场窄带源和一个各向同性的低功率噪声[1]。In this work, the model of the field directionalityis adopted in the following way. 在本文中，场方向性的模型以以下方式被采用。First, the bearing angle space is uniformly sampled into a large number of discreteangles. 首先，象限角空间被均匀取样成大量分离的角度。Next, it is assumed that ether the high energy that corresponds to the far-field strong sources or the low-energythat corresponds to the isotropic noise is received at the sensorarray from every of these discrete azimuth angles. 其次，假设与远场强源相应的高能量及与各向同性噪声相应的低能量都在传感器阵列处被从这些分离的方位角的每一个角度被接收。（译注：这里的ether漏字了，现按either翻译，如实neither则意思相反）
对于圆检测，许多研究人员已经运用参数分解和/或圆的一些几何性质，搞出了霍夫变换的变体以减少计算的复杂性。Yuen等人在1990年的论文中已经对圆的识别的集中霍夫变换的技术进行了比较研究。以参数分解为基础的方法通常是先检测圆心，然后确定半径。这样做的特点的其中之一是圆上一点的方向向量经过圆心(Davies, 1987a; Illingworth and Kittler, 1987). 叶等人在1992年的论文中用到一个性质：圆上两点的切线平行，那么这两点就是圆的直径的两个端点。上述方法需要有对干扰因素十分敏感的边缘等级线的梯度的信息(Davies, 1987b). 干扰因素对边的方向的作用通常要比对边的位置的作用大。不使用边缘方向信息的几种途径包括：陈和Siu（1990）提出了基于水平和垂直弦的中分线的快速椭圆检测法。同样，Ho和陈（1995）提出了一种使用全局几何对称性的快速检测圆的算法，通过水平和垂直对称轴计算出圆心。Sheu等人在1997年的论文中，在整个过程中运用了对称轴的信息来计算所有五个参数。 Goneid等人在1997年的论文中使用一维数组创建了弦的中分线法。Davies（1999）研究了一个用于椭圆的快速精确定位的简单的弦的中垂线法。 Ioannou 等人（1999年）的方法是基于垂径定理。Lei和王（1999）发现了对称轴，继而发现了几对交点是圆心的可选值的正交轴。其缺点是图像中的直线会让对称轴的检测更复杂。
多家比较价格和服务涵盖项目，然后根据自己的实际需求，选择一家最适合自己的服务，这才是明智之举。找北京译顶科技，性价比高，我就是在那边做的。你可以统一去知道了解下
摘要：进入本世纪以来，以互联网为核心的的网络通信技术已经得到飞速的发展和广泛的应用，世界经济的全球化趋势不可逆转。 Abstract: in the since the turn of the century, the Internet as the core in the network communication technology has been rapid development and the widespread application, the globalization trend of the world economy is irreversible. 在二十一世纪第二个十年的今天，我们已经走入网络经济时代，企业利用互联网有效开展网络营销活动，寻找新的商机，已经成为了一种必然的选择。 In the second decade of the 21st century, we had walked into the network today economic times, enterprise use the Internet to effectively develop network marketing activities, looking for new business opportunities, has become a kind of inevitable choice. 本文从网络营销的内涵入手，探讨了加多宝集团王老吉凉茶的经典网络营销案例，对这一案例的营销创新、存在的不足及网络营销细节问题进行了分析，，并针对加多宝集团在我国的发展、实施的障碍，提出了措施和对策。 This article from the network marketing, probes into the connotation of WangLaoJi cool tea add much treasure group the classic network marketing case, the case of marketing innovation, the shortcomings of the details and network marketing, analyzes the problems, and in the light of the stupa group in China with the development, implementation, and puts forward measures and obstacles countermeasures. 关键词：网络营销 加多宝集团 王老吉 营销策略 发展 障碍 措施 Keywords: network marketing WangLaoJi add much treasure group marketing strategy development obstacle measures
问题一：毕业论文外文翻译是什么意思？有什么要求？ 外文翻译要求：（1）选定外文文献后先给指导老师看，得到老师的确认通过后方可翻译。（2）选择外文翻译时一定选择外国作者写的文章，可从学校中知网或者外文数据库下载。（3）外文翻译字数要求3000字以上，从外文互章起始处开始翻译，不允许从文章中间部分开始翻译，翻译必须结束于文章的一个大段落。 问题二：毕业设计的外文翻译有字数要求吗 难道你们的任务书没有要求么？不然问问指导老师啊~不同学校不同专业要求也会不一样。 问题三：外文翻译需要注意的地方和遵守的原则有哪些？ 任何外文翻译不需遵循的三条黄金原则是：1。信：意思是要忠实于原文的信息，不能改变原文的意思，尤其是翻译科技类，经济类文章，这条很重要2。达：就是要通顺，要尊重目标语言的习惯，比如将英文翻译成中文时，要在坚持“信”的原则下，是翻译更加贴近中文的习惯。3。雅：要有文采。当然这也可以称之为翻译的三种境界，它们三者是相互联系而非矛盾的。 问题四：硕士论文对国外文献有数量要求吗？ 学校规定的是外文数量不少于总文献数量的1/3，当然了只是个规定而已，也没有人去专门查查到底占到几分之几，各个学校的规定到不一样。总之尽量多弄点英文文献吧，你懂的！ 参考文献可以在百度学术中找到。 毕业论文参考文献规范格式 一、参考文献的类型 参考文献（即引文出处）的类型以单字母方式标识，具体如下： M――专著 C――论文集 N――报纸文章 J――期刊文章 D――学位论文 R――报告 对于不属于上述的文献类型，采用字母“Z”标识。 对于英文参考文献，还应注意以下两点： ①作者姓名采用“姓在前名在后”原则，具体格式是：姓，名字的首字母. 如： Malcolm Richard Cowley 应为：Cowley, .，如果有两位作者，第一位作者方式不变，&之后第二位作者名字的首字母放在前面，姓放在后面，如：Frank Norris 与Irving Gordon应为：Norris, F. & .； ②书名、报刊名使用斜体字，如：Mastering English Literature，English Weekly。 二、参考文献的格式及举例 1.期刊类 [格式][序号]作者.篇名[J].刊名，出版年份，卷号（期号）：起止页码. [举例] [1] 王海粟.浅议会计信息披露模式[J].财政研究，2004,21(1)：56-58. [2] 夏鲁惠.高等学校毕业论文教学情况调研报告[J].高等理科教育，2004(1):46-52. [3] Heider, . The structure of color space in naming and memory of two languages [J]. Foreign Language Teaching and Research, 1999, (3): 62 C 67. 2.专著类 [格式][序号]作者.书名[M].出版地：出版社，出版年份：起止页码. [举例][4] 葛家澍，林志军.现代西方财务会计理论[M].厦门：厦门大学出版社，2001：42. [5] Gill, R. Mastering English Literature [M]. London: Macmillan, 1985: 42-45. 3.报纸类 [格式][序号]作者.篇名[N].报纸名，出版日期（版次）. [举例] [6] 李大伦.经济全球化的重要性[N]. 光明日报，1998-12-27(3). [7] French, W. Between Silences: A Voice from China[N]. Atlantic Weekly, 1987-8-15(33). 4.论文集 [格式][序号]作者.篇名[C].出版地：出版者，出版年份：起始页码. [举例] [8] 伍蠡甫.西方文论选[C]. 上海：上海译文出版社，1979：12-17. [9] Spivak,G. “Can the Subaltern Speak?”[A]. In & L. Gros *** erg(eds.). Victory in Limbo: Imigi *** [C]. Urbana: University of Illinois Press, 1988, . [10] Almarza, . Student foreign language teacher’s knowledg......>> 问题五：请问本科生毕业论文需要英文翻译吗？？？谢谢…… 每个学校的要求不完全相同。但是摘要和关键词肯定需要翻译成英文的。。 问题六：毕业论文外文文献翻译没有摘要关键词可以吗？ 10分 论文一般由题名、作者、摘要、关键词、正文、参考文献和附录等部分组成，其中部分组成（例如附录）可有可无。论文各组成的排序为：题名、作者、摘要、关键词、英文题名、英文摘要、英文关键词、正文、参考文献和附录和致谢。 下面按论文的结构顺序依次叙述。 题目 (一)论文――题目科学论文都有题目，不能“无题”。论文题目一般20字左右。题目大小应与内容符合，尽量不设副题，不用第1报、第2报之类。论文题目都用直叙口气，不用惊叹号或问号，也不能将科学论文题目写成广告语或新闻报道用语。 署名 (二)论文――署名科学论文应该署真名和真实的工作单位。主要体现责任、成果归属并便于后人追踪研究。严格意义上的论文作者是指对选题、论证、查阅文献、方案设计、建立方法、实验操作、整理资料、归纳总结、撰写成文等全过程负责的人，应该是能解答论文的有关问题者。往往把参加工作的人全部列上，那就应该以贡献大小依次排列。论文署名应征得本人同意。学术指导人根据实际情况既可以列为论文作者，也可以一般致谢。行政领导人一般不署名。 引言 (三)论文――引言是论文引人入胜之言，很重要，要写好。一段好的论文引言常能使读者明白你这份工作的发展历程和在这一研究方向中的位置。要写出论文立题依据、基础、背景、研究目的。要复习必要的文献、写明问题的发展。文字要简练。 材料方法 (四)论文――材料和方法按规定如实写出实验对象、器材、动物和试剂及其规格，写出实验方法、指标、判断标准等，写出实验设计、分组、统计方法等。这些按杂志对论文投稿规定办即可。 实验结果 (五)论文――实验结果应高度归纳，精心分析，合乎逻辑地铺述。应该去粗取精，去伪存真，但不能因不符合自己的意图而主观取舍，更不能弄虚作假。只有在技术不熟练或仪器不稳定时期所得的数据、在技术故障或操作错误时所得的数据、不符合实验条件时所得的数据才能废弃不用。而且必须在发现问题当时就在原始记录上注明原因，不能在总结处理时因不合常态而任意剔除。废弃这类数据时应将在同样条件下、同一时期的实验数据一并废弃，不能只废弃不合己意者。 实验结果的整理应紧扣主题，删繁就简，有些数据不一定适合于这一篇论文，可留作它用，不要硬行拼凑到一篇论文中。论文行文应尽量采用专业术语。能用表的不要用图，可以不用图表的最好不要用图表，以免多占篇幅，增加排版困难。文、表、图互不重复。实验中的偶然现象和意外变故等特殊情况应作必要的交代，不要随意丢弃。 讨论 (六)论文――讨论是论文中比较重要，也是比较难写的一部分。应统观全局，抓住主要的有争议问题，从感性认识提高到理性认识进行论说。要对实验结果作出分析、推理，而不要重复叙述实验结果。应着重对国内外相关文献中的结果与观点作出讨论，表明自己的观点，尤其不应回避相对立的观点。论文的讨论中可以提出假设，提出本题的发展设想，但分寸应该恰当，不能写成“科幻”或“畅想”。 问题七：你们有什么问题要问我的吗 英文翻译 答案Do you have any questions you would like to ask me采纳我吧！ 问题八：文献综述有字数要求吗.... 有，4000字左右，一般要看期刊的要求！ 问题九：英文翻译：我们应该提交哪些资料？ What data should we submit?问句应该用疑问句语序。
服务价格设定方面，考虑了不同文稿类型的差异性，以保证可以更加合理地安排不同编辑、根据不同文稿提供相应的最为专业的润色服务。找北京译顶科技做，那边这块做的很好⌄
毕业论文外文翻译：将外文参考文献翻译成中文版本。
翻译要求：
1、选定外文文献后先给指导老师看，得到老师的确认通过后方可翻译。
2、选择外文翻译时一定选择外国作者写的文章，可从学校中知网或者外文数据库下载。
3、外文翻译字数要求3000字以上，从外文文章起始处开始翻译，不允许从文章中间部分开始翻译，翻译必须结束于文章的一个大段落。
参考文献是在学术研究过程中，对某一著作或论文的整体的参考或借鉴。征引过的文献在注释中已注明,不再出现于文后参考文献中。外文参考文献就是指论文是引用的文献原文是国外的，并非中国的。
原文就是指原作品,原件，即作者所写作品所用的语言。如莎士比亚的《罗密欧与朱丽叶》原文是英语。
译文就是翻译过来的文字，如在中国也可以找到莎士比亚《罗密欧与朱丽叶》的中文版本，这个中文版本就称为译文。
主要标准
翻译是语际交流过程中沟通不同语言的桥梁。一般来说，翻译的标准主要有两条：忠实和通顺。
忠实
是指忠实于原文所要传递的信息，也就是说，把原文的信息完整并且准确地表达出来，使译文读者得到的信息与原文读者得到的信息大致相同。
通顺
是指译文规范、明白易懂，没有文理不通、结构混乱、逻辑不清的现象。
你现在在学校么？建议你到学校的图书馆去查（一般每个学校都会买网站使用权，这些特定的网站才有学术型的论文或者期刊的，一般我们自己网进不去这些网站），上中国知网，你将你论文题目输入，选择相似查找，和你论文题目一样或者相似的论文就会罗列出来了，然后你根据自己需要选择就可以。
CS方向sci三区的一个小刊，之前也是major revision，大四毕业了才中了。。所以在我心目中MV几乎约等于AC，虽然这辈子只投过一篇文章。北京译顶科技做的不错，可以联系他们一下 统一查下。
掌桥网站翻译与目前市场上面的翻译有所差别，掌桥的翻译工具就是专注于学术翻译服务，利用先进的解析技术，可以高效快速的翻译文献。虽然是收费服务，个人觉得比较专业。
？ 妈妈，你那么久， 即可连接没机会开奖号就离开咯及经历了来临了了路口
随着手机的普及，新一代移动通信系统的研究正如火如荼地进行中，从1995年问世的第一代(1G)模拟制式手机，到1996到1997年出现的第二代(2G)GSM、TDMA等数字制式手机，在经历了前两代的发展之后第三代(3G)移动通信技术手机，技术已经变得越来越成熟。中国的3G牌照在2009年1月7日正式下发，分别是移动(TD-SCDMA),联通(WCDMA)电信(CDMA2000),标明了中国正式进入3G时代！而3G网络也代表着这一技术的发展方向，而这一技术的研究并不是只言片语可以阐明，而这一技术的研究也显得非常地重要。 本论文完整的介绍了TD-SCDMA,WCDMA,CDMA2000三种不同的3G移动通信国际主流标准，覆盖了3G系统整体架构和相关知识点，对基础原理，无线接口技术，3G网络的特点，以及通信系统双工方式进行了阐述。 关键词：3G，移动通信，无线接口技术，双工方式 With the popularity of mobile phones, next-generation mobile communication system is in the middle of the study carried out in 1995 came from the first generation (1G) analog mobile phone system to the years 1996-1997 the second generation (2G) GSM, TDMA, etc. the number of standard mobile phones, after the first two generations after the development of third generation (3G) mobile communications technology mobile phones, technology has become more and more mature. China's 3G license in January 7, 2009 issued a formal, namely mobile (TD-SCDMA), Unicom (WCDMA) telecommunications (CDMA2000), marked China's formal entry into the 3G era! The 3G network also represents the direction of development of this technology, and this technology is not a word or two can be clarified, and this technology is also very important. This paper describes a complete TD-SCDMA, WCDMA, CDMA2000 three different international mainstream 3G mobile communications standard, covering the overall framework of 3G systems and related knowledge, the basic principle of the wireless interface technology, 3G network characteristics, as well as communication duplex mode system are described. Keywords: 3G, mobile communications, wireless interface technology, duplex mode
Although the twentieth Century 90 time metaphase, network community has begun to put the next generation network (NGN) or the next generation of Internet (NGI), but the researches focus on the IPv6 based technology. Until 2005, American global network of innovation environment (GENI) bodies in relevant documents publicly acknowledged that IPv6 failed to resolve the Internet challenge, we must re-examine the existing network system structure. So far, research on issues related to network architecture that has attracted wide attention from the academia and the industry at home and abroad, put forward many NGI/NGN architecture. Communication network is increasingly huge, advanced and complex, so it is difficult to describe the network structure with a structure chart, and according to the application demand of network architecture from more than one side design. Aiming at a series of challenges to deal with Internet, introduces a new network architecture: hierarchical switching network technology. With this technology, completely lost to the network router; regression simple; let the path packets can be predicted, the reasonable application of network channel resources; failure to change, the topology of the network, network equipment and communication lines and recovery, network management personnel misoperation incidents localization; let fast self-healing ability does not depend on another set of complex networks (such as SDH/SONET); let the multicast tree formed naturally; let the backbone network address space and the user address space separation of user behavior is easy to track. At the same time with the progress of related research situation at home and abroad, further analysis of the characteristics of the hierarchical network architecture, and builds a typical hierarchical network using Packet 。Tracer, to show the remarkable superiority.
Although the mid -1990s , the network industry has begun to raise the next generation network (NGN) or the next generation Internet (NGI), but focused on the research focus to IPv6 -based technologies. Until 2005 , the . Global Network Innovation Environment (GENI) institutions in the relevant documents publicly acknowledged IPv6 failed to solve the challenges facing the Internet , you must re-examine the existing network architecture. So far, the research questions about the network architecture was attracted wide attention in academia and industry , domestic and presented numerous NGI / NGN architecture. Growing communication network of giant , Advancement and complex, making it difficult to depict the structure of a network structure , and the needs of the network architecture should be applied from the plurality of side design . In this paper, a series of challenges to deal with the current Internet is difficult to introduce a new network architecture : hierarchical switching network technology. With this technique, completely lost router ; let network regression concise ; let the packet path predictable network channel resources to obtain reasonable application ; make changes in the network topology information , failure and recovery network equipment and communication lines , network management personnel localized incidents of misuse ; allow rapid healing ability is not dependent on another set of complex networks ( such as SDH / SONET); allow multicast tree formed naturally ; let backbone network address space separate from the user address space ; user bad behavior is easy to trace . Combined with domestic and foreign research progress of work -related cases, further analysis of hierarchical network architecture features and using Packet Tracer construct a typical hierarchical network , to demonstrate its significant advantages.
蓝牙技术允许信息存储在手机上可以显示在电视上，也可以变换分析的信息，以便在电脑上听声。 蓝牙技术的传输速率设计到1MHz。实现全双工通信的时间的协议是区为基础的电路交换和分组交换的组合。 通过无线芯片接收器与蓝牙技术的电子产品能够在十公尺，可连接传输速度可以达到每秒1万亿字节。 蓝牙技术是一种新的无线传输，在1998年推出。它实际上取代数据电缆的短距离无线通信技术，通过实现低带宽的点至点广播，或点对多点链路之间的信息交流。 点，以点传输，无线红外传输是一种，它是必要的，在准确的方向，而不是很远的地方。如果在中间有障碍物时，它不能穿过墙壁，且无法控制信息传输的速度。
基于WIN CE的ADSL线路参数研究ADSL line parameters research based on WIN CE CE (also known officially as Windows Embedded CE since version [2][3], and sometimes abbreviated WinCE) is a variation of Microsoft's Windows operating system for minimalistic computers and embedded systems. Windows CE is a distinctly different kernel, rather than a trimmed-down version of desktop Windows. It is not to be confused with Windows XP Embedded which is NT-based. It is supported on Intel x86 and compatibles, MIPS, ARM, and Hitachi SuperH CE is optimized for devices that have minimal storage—a Windows CE kernel may run in under a megabyte of memory. Devices are often configured without disk storage, and may be configured as a “closed” system that does not allow for end-user extension (for instance, it can be burned into ROM). Windows CE conforms to the definition of a real-time operating system, with a deterministic interrupt latency. It supports 256 priority levels and uses priority inheritance for dealing with priority inversion. The fundamental unit of execution is the thread. This helps to simplify the interface and improve execution has stated that the ‘CE’ is not an intentional initialism, but many people believe CE stands for ‘Consumer Electronics’ or ‘Compact Edition’; users often disparagingly called it “Wince”.[4] Microsoft says it implies a number of Windows CE design precepts, including “Compact, Connectable, Compatible, Companion, and Efficient.”[5] The first version, known during development under the codename “Pegasus”, featured a Windows-like GUI and a number of Microsoft's popular applications, all trimmed down for smaller storage, memory, and speed of the palmtops of the then, Windows CE has evolved into a component-based, embedded, real-time operating system. It is no longer targeted solely at hand-held computers. Many platforms have been based on the core Windows CE operating system, including Microsoft's AutoPC, Pocket PC 2000, Pocket PC 2002, Windows Mobile 2003, Windows Mobile 2003 SE, Windows Mobile , Windows Mobile 6, Smartphone 2002, Smartphone 2003 and many industrial devices and embedded systems. Windows CE even powered select games for the Sega Dreamcast, was the operating system of the controversial Gizmondo handheld, and can partially run on modified Microsoft Xbox game distinctive feature of Windows CE compared to other Microsoft operating systems is that large parts of it are offered in source code form. First, source code was offered to several vendors, so they could adjust it to their hardware. Then products like Platform Builder (an integrated environment for Windows CE OS image creation and integration, or customized operating system designs based on CE) offered several components in source code form to the general public. However, a number of core components that do not need adaptation to specific hardware environments (other than the CPU family) are still distributed in binary form toolsVisual StudioLate versions of Microsoft Visual Studio support projects for Windows CE / Windows Mobile, producing executable programs and platform images either as an emulator or attached by cable to an actual mobile device. A mobile device is not necessary to develop a CE program. The .NET Compact Framework supports a subset of the .NET Framework with projects in C# and , but not Managed C++.Platform BuilderThis programming tool is used for building the platform (BSP + Kernel), device drivers (shared source or custom made) and also the application. This is a one step environment to get the system up and running. One can also use Platform Builder to export an SDK (standard development kit) for the target microprocessor (SuperH, x86, MIPS, ARM etc.) to be used with another associated tool set named Visual C++ (eVC)The Embedded Visual C++ tool is for development of embedded application for Windows CE based devices. This tool can be used standalone using the SDK exported from Platform Builder or using the Platform Builder using the Platform Manager connectivity to Windows Mobile, Pocket PC, and SmartPhoneOften Windows CE, Windows Mobile, and Pocket PC are used interchangeably. This practice is not entirely accurate. Windows CE is a modular/componentized operating system that serves as the foundation of several classes of devices. Some of these modules provide subsets of other components' features (. varying levels of windowing support; DCOM vs COM), others which are mutually exclusive (Bitmap or TrueType font support), and others which add additional features to another component. One can buy a kit (the Platform Builder) which contains all these components and the tools with which to develop a custom platform. Applications such as Excel Mobile/Pocket Excel are not part of this kit. The older Handheld PC version of Pocket Word and several other older applications are included as samples, Mobile is best described as a subset of platforms based on a Windows CE underpinning. Currently, Pocket PC (now called Windows Mobile Classic), SmartPhone (Windows Mobile Standard), and PocketPC Phone Edition (Windows Mobile Professional) are the three main platforms under the Windows Mobile umbrella. Each platform utilizes different components of Windows CE, as well as supplemental features and applications suited for their respective PC and Windows Mobile is a Microsoft-defined custom platform for general PDA use, and consists of a Microsoft-defined set of minimum profiles (Professional Edition, Premium Edition) of software and hardware that is supported. The rules for manufacturing a Pocket PC device are stricter than those for producing a custom Windows CE-based platform. The defining characteristics of the Pocket PC are the digitizer as the primary Human Interface Device and its extremely portable SmartPhone platform is a feature rich OS and interface for cellular phone handsets. SmartPhone offers productivity features to business users, such as email, as well as multimedia capabilities for consumers. The SmartPhone interface relies heavily on joystick navigation and PhonePad input. Devices running SmartPhone do not include a touchscreen interface. SmartPhone devices generally resemble other cellular handset form factors, whereas most Phone Edition devices use a PDA form factor with a larger Mobile 5 supports USB and new devices running this OS will also conform to the USB Mass Storage Class, meaning the storage on PPC can be accessed from any USB-equipped PC, without requiring any extra software, except requiring a compliant host. In other words, you can use it as a flash productsCompetitors to consumer CE based PDA platforms like Pocket PC – the main application of Windows CE – are Java, Symbian OS, Palm OS, iPhone OS and Linux based packages like Qtopia Embedded Linux environment from Trolltech, Convergent Linux Platform from a La Mobile, and Access Linux Platform from Orange and secondary usage of CE is in devices in need of graphical user interfaces, (point of sale terminals, media centers, web tablets, thin clients) as the main selling point CE is the look and feel being similar to desktop Windows. The competition is Windows XP, Linux and graphical packages for simpler embedded operating an RTOS, Windows CE is also theoretically a competitor to any realtime operating system in the embedded space, like VxWorks, ITRON or eCos. The dominating method, however, of mixing Windows look and feel with realtime on the same hardware, is to run double operating systems using some virtualization technology, like TRANGO Hypervisor from TRANGO Virtual Processors or Intime from TenAsys in the case of Windows, and OS Ware from VirtualLogix, Padded Cell from Green Hills Software, OKL4 from Open Kernel Labs, TRANGO Hypervisor from TRANGO Virtual Processors, RTS Hypervisor from Real-Time Systems or PikeOS from Sysgo, in case of the Digital Subscriber Line (ADSL) is a form of DSL, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. It does this by utilizing frequencies that are not used by a voice telephone call. A splitter - or microfilter - allows a single telephone connection to be used for both ADSL service and voice calls at the same time. Because phone lines vary in quality and were not originally engineered with DSL in mind, it can generally only be used over short distances, typically less than 3mi ( km) [William Stallings' book].At the telephone exchange the line generally terminates at a DSLAM where another frequency splitter separates the voice band signal for the conventional phone network. Data carried by the ADSL is typically routed over the telephone company's data network and eventually reaches a conventional internet network. In the UK under British Telecom the data network in question is its ATM network which in turn sends it to its IP network IP distinguishing characteristic of ADSL over other forms of DSL is that the volume of data flow is greater in one direction than the other, . it is asymmetric. Providers usually market ADSL as a service for consumers to connect to the Internet in a relatively passive mode: able to use the higher speed direction for the "download" from the Internet but not needing to run servers that would require high speed in the other are both technical and marketing reasons why ADSL is in many places the most common type offered to home users. On the technical side, there is likely to be more crosstalk from other circuits at the DSLAM end (where the wires from many local loops are close to each other) than at the customer premises. Thus the upload signal is weakest at the noisiest part of the local loop, while the download signal is strongest at the noisiest part of the local loop. It therefore makes technical sense to have the DSLAM transmit at a higher bit rate than does the modem on the customer end. Since the typical home user in fact does prefer a higher download speed, the telephone companies chose to make a virtue out of necessity, hence ADSL. On the marketing side, limiting upload speeds limits the attractiveness of this service to business customers, often causing them to purchase higher cost Digital Signal 1 services instead. In this fashion, it segments the digital communications market between business and home usersHow ADSL worksOn the wireCurrently, most ADSL communication is full duplex. Full duplex ADSL communication is usually achieved on a wire pair by either frequency division duplex (FDD), echo canceling duplex (ECD), or time division duplexing (TDD). FDM uses two separate frequency bands, referred to as the upstream and downstream bands. The upstream band is used for communication from the end user to the telephone central office. The downstream band is used for communicating from the central office to the end user. With standard ADSL (annex A), the band from kHz to 138 kHz is used for upstream communication, while 138 kHz – 1104 kHz is used for downstream communication. Each of these is further divided into smaller frequency channels of kHz. During initial training, the ADSL modem tests which of the available channels have an acceptable signal-to-noise ratio. The distance from the telephone exchange, noise on the copper wire, or interference from AM radio stations may introduce errors on some frequencies. By keeping the channels small, a high error rate on one frequency thus need not render the line unusable: the channel will not be used, merely resulting in reduced throughput on an otherwise functional ADSL may support usage of higher frequencies as a proprietary extension to the standard. However, this requires matching vendor-supplied equipment on both ends of the line, and will likely result in crosstalk issues that affect other lines in the same is a direct relationship between the number of channels available and the throughput capacity of the ADSL connection. The exact data capacity per channel depends on the modulation method used.[edit] ModulationADSL initially existed in two flavours (similar to VDSL), namely CAP and DMT. CAP was the de facto standard for ADSL deployments up until 1996, deployed in 90 percent of ADSL installs at the time. However, DMT was chosen for the first ITU-T ADSL standards, and (also called and respectively). Therefore all modern installations of ADSL are based on the DMT modulation J and M shift the upstream/downstream frequency split up to 276 kHz (from 138 kHz used in the commonly deployed annex A) in order to boost upstream rates. Additionally, the "all-digital-loop" variants of ADSL2 and ADSL2+ (annexes I and J) support an extra 256 kbit/s of upstream if the bandwidth normally used for POTS voice calls is allocated for ADSL the ADSL access utilizes the MHz band, ADSL2+ utilizes the MHz downstream and upstream rates displayed are theoretical maxima. Note also that because Digital subscriber line access multiplexers and ADSL modems may have been implemented based on differing or incomplete standards some manufacturers may advertise different speeds. For example, Ericsson has several devices that support non-standard upstream speeds of up to 2 Mbit/s in ADSL2 and ADSL2+.[edit] Installation issuesDue to the way it uses the frequency spectrum, ADSL deployment presents some issues. It is necessary to install appropriate frequency filters at the customer's premises, to avoid interferences with the voice service, while at the same time taking care to keep a clean signal level for the ADSL the early days of DSL, installation required a technician to visit the premises. A splitter was installed near the demarcation point, from which a dedicated data line was installed. This way, the DSL signal is separated earlier and is not attenuated inside the customer premises. However, this procedure is costly, and also caused problems with customers complaining about having to wait for the technician to perform the installation. As a result, many DSL vendors started offering a self-install option, in which they ship equipment and instructions to the customer. Instead of separating the DSL signal at the demarcation point, the opposite is done: the DSL signal is "filtered off" at each phone outlet by use of a low pass filter, also known as microfilter. This method does not require any rewiring inside the customer side effect of the move to the self-install model is that the DSL signal can be degraded, especially if more than 5 voiceband devices are connected to the line. The DSL signal is now present on all telephone wiring in the building, causing attenuation and echo. A way to circumvent this is to go back to the original model, and install one filter upstream from all telephone jacks in the building, except for the jack to which the DSL modem will be connected. Since this requires wiring changes by the customer and may not work on some household telephone wiring, it is rarely done. It is usually much easier to install filters at each telephone jack that is in use.
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