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101.
以舰载雷达的综合保障为研究对象,分析了部队现行的保障体制。在此基础上,结合未来综合保障的发展方向,从远程支持保障、物资保障、精确化保障、可视化保障和人力资源保障等方面探讨了舰载雷达综合保障的新方法和新设想。 相似文献
102.
烟气轮机机组是利用余热发电的原理回收高温热能再生电能,但是由于多方面的原因,烟气轮机机组时常发生故障,对生产的经济性和安全性造成巨大损失。为了保障设备正常运行,对设备进行实时监测,及时判断故障发生的可疑点,减少故障发生的频率,同时保护环境,采用对原始信号的3层小波分解,提取信号的特征向量,再采用C-SVC和V参数支持向量机二种方法进行分类实验,得到V参数的支持向量机分类效果最佳。 相似文献
103.
针对突发自适应调制信号中的PSK和QAM调制方式识别问题,本文提出了一种能够识别BPSK、QPSK、8PSK以及16QAM、32QAM、64QAM、128QAM、256QAM八种信号类型的盲识别算法。该算法首先对信号的循环平稳性进行了分析和讨论,给出了利用循环高阶累积量的特征实现信号识别分类的理论依据。然后,提出了三种基于循环累积量的特征分别实现了QAM和PSK类间识别、MPSK类内识别以及方形QAM与十字形QAM的识别。最后通过对MQAM信号的瞬时幅度分布特性的深入研究和分析,提出了一种基于瞬时包络平方的方差的特征实现了QAM的类内识别。该算法选择了二叉树支持向量机作为识别分类器,并设计了一种新的识别流程完成了对上述信号调制方式的识别。该算法无需精确同步,对载波相位具有较好的鲁棒性,并能够对中频信号进行识别。仿真实验表明,该算法能够实现在较低信噪比条件下突发信号的识别。 相似文献
104.
Integration of different kinds of wireless networks to provide people seamless and continuous network access services is a
major issue in the B3G network. In this paper, we propose and implement a novel Heterogeneous network Integration Support
Node design (HISN) and a distributed HISN network architecture for the integration of heterogeneous networks, under which
the Session Mobility, Personal Mobility, and Terminal Mobility for mobile users can be maintained through the Session Management
mechanism. Thus, the HISN node can serve as an agent for the user to access Internet services independent of underlying communication
infrastructure. Our design is transparent to the bearer networks and the deployment of the HISN network does not need to involve
the operators of the heterogeneous wireless networks.
This paper is an extension of the work that won the championship of the Mobile Hero contest sponsored by Industrial Development
Bureau of Ministry of Economic Affairs, Taiwan, R.O.C., and was awarded USD 30,000. The work of Lin, Chang and Cheng was supported
in part by the National Science Council (NSC), R.O.C, under the contract number NSC94-2213-E-002-083 and NSC94-2213-E-002-090,
and NSC 94-2627-E-002-001, Ministry of Economic Affairs (MOEA), R.O.C., under contract number 93-EC-17-A-05-S1-0017, the Computer
and Communications Researches Labs/Industrial Technology Research Institute (CCL/ITRL), Chunghwa Telecom Labs, Telcordia Applied
Research Center, Taiwan Network Information Center (TWNIC), and Microsoft Corporation, Taiwan. The work of Fang was supported
in part by the US National Science Foundation Faculty Early Career Development Award under grant ANI-0093241 and US National
Science Foundation under grant DBI-0529012.
Phone Lin (M’02-SM’06) received his BSCSIE degree and Ph.D. degree from National Chiao Tung University, Taiwan, R.O.C. in 1996 and
2001, respectively. From August 2001 to July 2004, he was an Assistant Professor in Department of Computer Science and Information
Engineering (CSIE), National Taiwan University, R.O.C. Since August 2004, he has been an Associate Professor in Department
of CSIE and Graduate Institute of Networking and Multimedia, National Taiwan University, R.O.C. His current research interests
include personal communications services, wireless Internet, and performance modeling. Dr. Lin is an Associate Editor for
IEEE Transactions on Vehicular Technology, a Guest Editor for IEEE Wireless Communications special issue on Mobility and Resource
Management, and a Guest Editor for ACM/Springer MONET special issue on Wireless Broad Access. He is also an Associate Editorial
Member for the WCMC Journal. P. Lin’s email and website addresses are plin@csie.ntu.edu.tw and http://www.csie.ntu.edu.tw/∼plin,
respectively.
Huan-Ming Chang received the BSCSIE degree and Master CSIE degree from National Taiwan University, R.O.C. in 2003 and 2005, respectively.
His current research interest includes wireless Internet. H.-M. Chang’s email address is r91114@csie.ntu.edu.tw.
Yuguang Fang received a Ph.D. degree in Systems and Control Engineering from Case Western Reserve University in January 1994, and a Ph.D.
degree in Electrical Engineering from Boston University in May 1997. From June 1997 to July 1998, he was a Visiting Assistant
Professor in Department of Electrical Engineering at the University of Texas at Dallas. From July 1998 to May 2000, he was
an Assistant Professor in the Department of Electrical and Computer Engineering at New Jersey Institute of Technology. In
May 2000, he joined the Department of Electrical and Computer Engineering at University of Florida where he got the early
promotion to Associate Professor with tenure in August 2003 and to Full Professor in August 2005. He has published over 180
papers in refereed professional journals and conferences. He received the National Science Foundation Faculty Early Career
Award in 2001 and the Office of Naval Research Young Investigator Award in 2002. He is currently serving as an Editor for
many journals including IEEE Transactions on Communications, IEEE Transactions on Wireless Communications, IEEE Transactions
on Mobile Computing, and ACM Wireless Networks. He is also actively participating in conference organization such as the Program
Vice-Chair for IEEE INFOCOM’2005, Program Co-Chair for the Global Internet and Next Generation Networks Symposium in IEEE
Globecom’2004 and the Program Vice Chair for 2000 IEEE Wireless Communications and Networking Conference (WCNC’2000).
Shin-Ming Cheng received the BSCSIE degree in 2000 from National Taiwan University, Taiwan, R.O.C., where he is currently working toward
the Ph.D. degree in the Department of Computer Science and Information Engineering, National Taiwan University. His current
research interests include mobile computing, personal communications services, and wireless Internet. S.-M. Cheng’s email
and website addresses are shimi@pcs.csie.ntu.edu.tw and http://www.pcs.csie.ntu.edu.tw/∼shimi, respectively. 相似文献
105.
为了解决单样本掌纹识别的困难,研究了基于最近相关性分类器(NCC)的单样本掌纹识别方法。首先对掌纹图像进行分块,划分为若干个子图像;然后运用统计特征、傅里叶变换、离散余弦变换(DCT)和Gabor变换4种方法对子图像进行特征提取,将所有子图像的特征向量组合在一起形成该图像的特征向量;最后应用NCC进行分类识别。运用PolyU掌纹图像库,对本文算法进行测试。实验结果表明:与最近邻分类器(NNC)和支持向量机(SVM)相比,在不同大小的子图像上,运用不同的特征提取算法,NCC均提高了识别率;分类时间在0.3~0.7s之间,满足实时系统的需求。 相似文献
106.
从面向对象教学面临的困境入手,结合学生的学习心理和认知规律,分析了产生问题的主客观原因,提出了"先过程,后对象"的教学理念,从教材建设、教学内容安排上阐述了教学内容的具体组织实施过程;从教学思路、教学观念、教学手段几方面探讨了教学方法的改革。 相似文献
107.
108.
地理空间信息网格基础底层的相关技术主要有地理空间信息网格计算结点的构建技术、传统网络协议技术、下一代网络协议技术、接口技术等。作为创新技术,地理空间信息网格必须依托已有技术,加之相关领域及更先进的技术支持,才会有发展和前途。 相似文献
109.
基于交通问卷调查结果,首先分析了交通电子执法环境下设置提示标志的必要性及原则,其次分析了交通提示标志在提升电子执法威慑力时发挥的作用,最后结合我国国情,对交通提示标志在应用过程中存在的问题进行了剖析,并提出了相应的改善建议,以期降低电子执法环境下交通违法率、提高道路交通安全水平。 相似文献
110.
针对装备保障和现代战争的特点,分析了传统维修保障模式的不足,有针对性地从保障人员队伍建设、保障设备配置,以及保障资料整理、备品备件的管理和保障运作流程等方面提出了一些优化思路、基本途径及优化后的效果,对提高保障效率、降低保障成本有参考意义。 相似文献