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1.
本文介绍了新媒体技术的主要应用模式:数字电视、IPTV网络电视和移动电视,以及其中涉及的关键技术——信源编码技术、信道编码技术、调制技术、数字版权管理技术、IP组播技术、内容分发网络技术、电子节目指南技术、机顶盒技术等。  相似文献   

2.
阐述物联网通信系统中的感知控制层通信技术和网络传输层通信技术,包括RFID射频识别技术、蓝牙技术、ZigBee技术、NFC近距离无线通信技术、Wi-Fi技术、UWB超宽带技术。  相似文献   

3.
本文从船舶电气的发展现状入手,着重分析了船舶综合自动化技术、驾驶导航技术、海上遇险安全技术、全球定位技术、自动识别技术、航行数据记录技术、综合通讯技术等主要技术,并探索了船舶电气主要技术的发展趋势。  相似文献   

4.
《信息与电子工程》主要围绕信息化新军事变革中电子信息技术发展的需要,及时传播信息与电子工程领域的新理论、新技术、新成果。重点报道内容:信息工程技术、无线电测控通信技术、雷达技术、自动控制技术、天线技术、微波毫米波技术、高功率微波技术、电子信息对抗技术、微电子与微机电技术、引信技术、电  相似文献   

5.
本文以标准化技术为基础,通过自动控制技术、数字信息技术、网络传输技术、网络安全技术、数据库技术、数据传输技术、数据压缩和解压缩技术等多方面的技术相融合,建立一个功能齐全、技术先进、统一调度、集中监控发射机、电力、环境和安防等的智能化、网络化管控平台。  相似文献   

6.
虚拟现实技术是一项新兴技术,结合了多种技术如多媒体技术、计算及图形技术、网络技术、人机交互技术、仿真技术以及立体显示技术等等,前景非常的广阔。文章结合了虚拟现实技术国内外的研究现状对虚拟现实技术的发展趋势进行了分析。  相似文献   

7.
仪器仪表产品的高科技化,必将成为日后仪器仪表科技与产业的发展主流世界近二十年来,微电子技术、计算机技术、精密机械技术、高密封技术、特种加工技术、集成技术、薄膜技术、网络技术、纳米技术、激光  相似文献   

8.
跨世纪的通信技术是先进的数字技术、计算机技术、微电子与光电子技术相结合的高新技术,本文就跨世纪技术的几个主要方面:通信网络技术、光纤通信技术、卫星通信技术、移动通信技术、现代军事通信技术的发展趋势作了概要分析。  相似文献   

9.
概述了国内外半导体设备技术动态,介绍了光刻技术、CMP技术、膜生长技术、刻蚀技术、离子注入技术、清洗技术及封装技术的发展现状和技术趋势,预测了全球半导体制造设备未来市场变化,并提出了国产半导体设备技术创新的途径。  相似文献   

10.
光开关研究新进展   总被引:6,自引:0,他引:6  
文章比较全面地综述了近几年来各种光开关技术的研究进展,包括微光机电系统(MOEMS)技术、气泡技术、液晶技术、全息光栅技术、热光技术及声光技术等,并详细分析了各种技术相应的发展状况、技术特点和发展趋势。  相似文献   

11.
Towards Mobile Ubiquitous Service Environment   总被引:2,自引:0,他引:2  
In this article we present a perspective on future vision of mobile communications and services which is referred to as Mobile Ubiquitous Service Environment (MUSE). Based on analysis of wireless communications and services, we exploit a conceptual model for MUSE via a top-down approach. The conceptual model consists of three major elements: Terminal Service Environment (TSE), Network Service Environment (NSE) and User Identity (UID). The concept of Always the Best Experience (ABE) is addressed as the hinge in design and development such that the user-centric services could be provided automatically and intelligently in the future diverse wireless world Based on these, we further discuss the issues on design and implementation of architecture of future wireless communication system. Requirements for architecture brought by the new features of MUSE are listed. Moreover, we also address several tradeoffs that should be taken into consideration in design. Finally, the deployment challenges for MUSE, such as reflectiveness of system, security and privacy, as well as peer-to-peer AAA are predicted.Ji Yang received PhD degree on Circuit and System, Bachelor degree on Telecommunication Engineering from Beijing University of Posts and Telecommunications (BUPT) in 2002 and 1993 respectively. Currently, he is an associate professor of BUPT, chief technical supervisor of Wireless Technology Innovation Institute, and vice manager of MTlab of Sino-Germany Software Institute. He leads the research on service and application in Future Forum in China. He also made much contribution to the China Communication Standardization Association (CCSA), including the vision of future Mobile Ubiquitous Service Environment, architecture of future B3G mobile terminal, etc. His research interests include architecture design for mobile ubiquitous networks, theory of self-organization, etc.Zhang Ping is now the professor of Beijing University of Posts and Telecommunications and director of Wireless Technology Innovation (WTI) Institute, BUPT. He has also served on the senior member of C3G Group, China MOST 863 future mobile communication FuTURE project, vice-chairman of China FuTURE Forum, and member of Vision Committee of World Wireless Research Forum(WWRF), he was vice chair of WWRF in 2005. He is also invited as the consultants for many domestic and oversea communication companies. He is very active on the international research activity on Beyond 3G area. He also participated in several European projects such as E2R and MOCCA. Until now, he has published 6 books, around 400 publications in journals and conferences in the area of telecommunications. His main research interests are theory and applications in wireless communication area. He was awarded by government, city of Beijing and Ministry of Information Industry several times for his great contribution to the industry and research activity in China.Hu Zheng is a PH.D candidate in mobile communications engineering in Wireless Technology Innovation Institute (WTI) at Beijing University of Posts and Telecommunications (BUPT). He received B.S degree from Nanjing University of Posts and Telecommunications in 2002, majoring in computer communications engineering. He currently works on serivce aspects of mobile ubiquitous communication system with focus on design and performance evaluation of interaction protocols and services in self-organized service environment.Wang Xu received the B.Tech. degree in electronic engineering from Beijing Polytechnic University (now named as Beijing University of Technology), Beijing, China, in 2002. Now he is working for his Ph.D. degree in Wireless Technology Innovation (WTI) Institute, Beijing University of Posts and Telecommunications (BUPT). His current interests include wireless communications in personal area, ad hoc networks and peer-to-peer system.Li Yinong received the BS degree major in Telecommunication Engineering in 1993 from Beijing University of Posts and Telecommunications, the MS degree and PhD degree major in Telecommunication and Electronic System in 1995 and 2003 from the Beijing University of Posts and Telecommunications. He is currently a lecture of STE (School of Telecommunication Engineering) of BUPT. His main research interests include service modeling, service composition approach, and intelligent service. In BUPT, he has given several lectures to both graduate and undergraduate students such as Information Theory, Speech Recognition, Pattern Recognition and Artificial Intelligence.  相似文献   

12.
空间互联网技术是人类进行航天测控、导航定位、远洋航行等空间应用的基础支撑,是实现全球互联互通的关键手段。首先介绍了空间互联网的概念及内涵、组成及结构、特点及优势等相关基础知识,接着总结了空间互联网的关键技术,然后阐述了空间互联网的发展现状和面临的问题,最后结合互联网技术发展趋势和航天应用的发展要求,对空间互联网技术的发展趋势进行了展望和预测。  相似文献   

13.
This paper presents a unified treatment of various important signal processing techniques for the extraction of the instantaneous envelope and phase of a real signal. These techniques include Complex Demodulation, Hilbert Transformation, In-Phase and In-Quadrature Filtering, Phase-Locked Loop Demodulation, and Peak Amplitude and Zero-Crossing Detection. The salient points in the mathematical theory and implementation of these techniques are outlined, as well as their interrelationships via the theory of analytic signals. The advantages and limitations of each of these techniques are elaborated upon, and Complex Demodulation is shown to be the most effective and flexible method from an implementation point of view. The relation of the above techniques to Fourier spectrum analysis is elucidated, and an example is presented of applying Complex Demodulation for the quantification of time nonstationarities in the electrographic morphology of an EEG waveform.  相似文献   

14.
随着流媒体应用的蓬勃兴起,音频信号的自动分类开始成为工程与学术关注的热点之一。根据音乐信号对乐曲表现的情绪进行分类,由于涉及音乐信号的社会属性和自然属性的综合表征与模糊分类,因此处理方法相应需要在各种传统表征与分类方法的基础上进行机制筛选与架构优化。该文探讨了在AdaBoost算法,K-L变换和GMM模型的基础上构造弱分类器的方法,采用多层分类器结构,成功地实现了对音乐信号进行情绪分类。初步的实验对163首歌曲进行平静(Calm),悲伤(Sad),激动(Exciting)以及愉悦(Pleasant)4种类别的分类,训练集和测试集的分类准确率分别达到97.5%和93.9%,展示了这种方法的可行性和进一步发展的潜在价值。  相似文献   

15.
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   

16.
The anisotropic growth of one-dimensional or filamental crystals in the form of microwires and nanowires constitutes a rich domain of epitaxy and newly enabled applications at different length and size scales. Significant progress has been accomplished in controlling the growth, morphology, and properties of semiconductor nanowires and consequently their device level performance. The objective of this review is two-fold: to highlight progress up to date in nanowire doping and to discuss the remaining fundamental challenges. We focus on the most common semiconductor nanowire growth mechanism, the vapor-liquid-solid growth, and the perturbation of its kinetic and thermodynamic aspects with the introduction of dopants. We survey the origins of dopant gradients in nanowire growth and summarize quantification techniques for dopants and free-carrier concentrations. We analyze the morphological changes due to dopants and the influence of growth droplet seeds on composition and morphology and review growth aspects and alternatives that can mitigate these effects. We then summarize some of the remaining issues pertaining to dopant control in nanowires.  相似文献   

17.
李峰 《长江信息通信》2021,34(2):167-171
数字经济时代,企业面临更加激烈的市场竞争环境,传统的供应链管理模式的问题日趋显现,亟需进行数字化转型。企业的发展需要更加智能、高效的数字化供应链的支撑。针对这一现状和需求,文章着力于研究如何解决传统企业供应链数字化转型的问题,设计了一套基于SAP ERP和EWM系统为核心的企业数字化供应链的解决方案:通过SAP ERP和EWM系统的无缝对接实现了企业物流相关业务的自动流转;通过EWM与WCS系统的无缝对接以及WCS系统与自动化立体仓库硬件设备的集成实现了仓库所有出入库作业的自动传递和执行;通过引入条码技术以及与RF设备的集成实现了全流程作业的自动识别和准确高效的处理。该解决方案的设计与实现,帮助企业极大地提高了供应链各个环节的作业效率,提高了整个供应链的透明度,进而提升了企业的整体运营效率和管理水平,使得企业能在日趋激烈的市场竞争环境中保持竞争优势,并取得长足发展。  相似文献   

18.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

19.
现代通信网络应能满足各种通信业务和通信容量日益发展的需求,实现话音、数据、视频、IP等业务的一体化综合交换和传输。在比较TDM、IP和ATM三种协议的基础上,提出"采用内置RPR和MPLS功能的MSTP平台"建设光纤综合通信网络平台的实现方法。MSTP采用SDH的数据帧结构,保持了SDH标准光接口、灵活分插低速信号、自愈环保护和功能强大的网管等优点,可对TDM、IP和ATM协议进行优化传输。  相似文献   

20.
提供了一种用于安德鲁反射测量样品制备新方法. 该方法采用聚焦粒子束刻蚀和磁控溅射,可以获得可控的、干净的、无应力的纳米接触用于自旋极化探测. 所制备的样品中,磁性和非磁性材料样品的反射谱都表现出复杂的峰和谷结构,这些结构可能源于与界面相关的零偏压反常以及与激发态相关的准离子相互作用. 对另一个Co40Fe40B20合金样品采用简单的钕针尖压针方法进行了对比性测量,反射谱中没有观察到谷结构,但谱结构出现较明显的热扩展,这种热扩展可能来源于界面处的非弹性输运. 所有的反射谱目前还不能由现有的理论给出令人满意的解释. 利用点接触反射方法获得可靠的自旋极化信息还有赖于接触界面特征的进一步分析. 而一个更切合实际的、更完善的理论成为迫切的需要.  相似文献   

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