Variable-weight optical orthogonal code (OOC) was introduced by G. C. Yang [IEEE Trans. Commun., 1996, 44: 47-55] for multimedia optical CDMA systems with multiple quality of service (QoS) requirements. In this p...Variable-weight optical orthogonal code (OOC) was introduced by G. C. Yang [IEEE Trans. Commun., 1996, 44: 47-55] for multimedia optical CDMA systems with multiple quality of service (QoS) requirements. In this paper, seven new infinite classes of optimal (v, {3,4,6}, 1, Q)-OOCs are constructed.展开更多
准确提取海岸水边线是海岸线变迁研究中必不可少的基本工作。本文以海南省陵水黎族自治县2016年的GF-2影像为数据源,在大气校正和正射校正等预处理的基础上,结合数学形态学处理等方法,采用NDWI(Normalized Difference Water Index)阈值...准确提取海岸水边线是海岸线变迁研究中必不可少的基本工作。本文以海南省陵水黎族自治县2016年的GF-2影像为数据源,在大气校正和正射校正等预处理的基础上,结合数学形态学处理等方法,采用NDWI(Normalized Difference Water Index)阈值法、ISOADTA(Iterative Self-Organizing Data Analysis Technique Algorithm)、SVM(Support Vector Machine)和面向对象法(Object-Oriented Classification,OOC)等4种不同方法来对海岸水边线进行提取,并对其提取结果进行定性和定量评估,进而分析比较了这4种方法在提取人工海岸、砂质海岸和基岩海岸等3种不同海岸类型的水边线时的提取效果和提取精度。结果表明,SVM方法在3种海岸水边线上的总体提取效果最好,总体提取精度最高。展开更多
基金The authors wish to thank the anonymous referees for their comments and suggestions that improved the quality of this paper. This work was supported in part by the National Natural Science Foundation of China (Crant No. 11271089), Guangxi Science Foundation (Crant No. 2012GXNSFAA053001), and the Foundation of Cuangxi Education Department (No. 201202ZD012).
文摘Variable-weight optical orthogonal code (OOC) was introduced by G. C. Yang [IEEE Trans. Commun., 1996, 44: 47-55] for multimedia optical CDMA systems with multiple quality of service (QoS) requirements. In this paper, seven new infinite classes of optimal (v, {3,4,6}, 1, Q)-OOCs are constructed.