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1.
采用自制的低压金属有机化学气相淀积设备,用三甲基镓、三甲基铟作为Ⅲ族源,三甲基锑和砷烷作为Ⅴ族源在(100)面GaSb和GaAs单晶衬底上分别外延生长了InAsSb材料.用X射线双晶衍射、原子力显微镜、扫描电镜和电子探针能谱仪等对材料特性进行了表征,研究了生长温度、Ⅴ/Ⅲ比、过渡层等生长参数对外延层质量的影响.获得了与GaSb衬底晶格失配度为0.4%的表面光亮且晶体质量较好的InAs0.85Sb0.15外延层.  相似文献   

2.
"本土厂商的败退,导致外资品牌平板电视在国内市场的整体销售额比重增至59%,外资品牌再次超越国产品牌"<涨或降?国产平板价格走向两难>,"商业",2007年8月20日).现在看来,贵刊这篇文章借用的德国人提供的数据,并未对国产品牌彩电提供商的现状故到准确了解.而笔者在参观了今年高交会的家电展厅后,更加认识到外资品牌已被国内同行甩在了身后.  相似文献   

3.
提出了一种基于ARM的嵌入式VoIP终端平台.接入PSTN和家庭宽带,可以实现拨打IP电话和普通PSTN电话的功能.与现有VoIP设备相比,具有成本低,方便易用等优点.给出了该平台的硬件和软件构成.  相似文献   

4.
拥有一套血统纯正的欧陆音响器材,是很多发烧友梦寐以求的.原因无他,但求高贵醇厚的音乐味而已.不管你对欧洲品牌的看法如何,在音乐味表现上,相近的价位带里面,相对来讲源自欧洲的品牌器材的确要更有优势、更讨好一些,也难怪发烧友们情有独钟.  相似文献   

5.
胡平生 《半导体技术》2006,31(9):662-665
问:丁总,您好!十分有幸能有机会采访您.3M是一家国际知名的多元化公司,作为3M中国有限公司电子、电力及通讯事业部总经理,您能为我们简单介绍一下3M产品在半导体领域的一些应用吗?  相似文献   

6.
江西电信基于专业GIS创新应用   总被引:1,自引:0,他引:1  
一、前言中国电信作为通信企业,拥有众多的管线资源和通讯设备,如管线、人手井、管孔、电缆、光缆,这些设备分布区域广,种类繁多,多年来一直采用图纸  相似文献   

7.
编者按:1月11日下午国家发改委和信息产业部公布,"降低手机国内漫游通话费上限标准听证会"拟于1月22日在北京召开.这一消息的发布引起了社会各届人士的关注,<通信世界>周刊委托北京信索信息咨询有限公司特针对相关话题进行调查,以了解民众对于此事的反应和态度.  相似文献   

8.
赵雪芹 《今日电子》2005,(6):118-119
4月23日,德国菲尼克斯电气集团在其亚太地区总部中国南京举行新闻发布会,公布菲尼克斯电气全球TNC CoC战略中国决策(TNC是跨国公司Trans Nation Company的简称,CoC是竞争力中心Center of Competence的简称),并正式推出全球首套自动化控制软件PCWORX中文版,同时宣布在中国推出划时代的工业以太网技术标准—PROFINET.  相似文献   

9.
本文对大型UPS使用现状提出两点建议:一是提供独立的主路输入和旁路输入电源,提高供电环节的可靠性;二是设置外置开关组,解决UPS系统使用的"灵活性"问题.  相似文献   

10.
几个月前,我针对航空系统的一些技术发展发表了评论.而在最近几星期,这个领域似乎出现了快速的进展,不是在技术方面,而是有关于法规和作业规定,这是源自于英国电信传播管理局(UK telecommunications regulator Ofcom)和欧盟执行委员会(European commission)所发表的声明.  相似文献   

11.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

12.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

15.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

16.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

17.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

18.
正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first  相似文献   

19.
20.
LI Shaoqian 《中国通信》2014,(6):I0001-I0002
The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave (ram-wave) frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.  相似文献   

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