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一种多属性递进网格模型生成算法研究
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作者 聂军洪 张丽艳 +2 位作者 唐杰 周来水 周儒荣 《应用科学学报》 CAS CSCD 2003年第3期302-307,共6页
提出了一种新的多属性递进网格模型生成算法.该算法将表征网格顶点信息的向量由简单的三维几何信息扩展到包含附属信息的多维向量,可生成带有颜色、纹理等附属信息的递进网格模型.递进网格模型由一个简化网格和一个细化序列构成.该算法... 提出了一种新的多属性递进网格模型生成算法.该算法将表征网格顶点信息的向量由简单的三维几何信息扩展到包含附属信息的多维向量,可生成带有颜色、纹理等附属信息的递进网格模型.递进网格模型由一个简化网格和一个细化序列构成.该算法在生成细化序列时,将简化网格模型的顶点局限于初始网格模型的顶点集中,减少了细化序列所包含的信息,降低了所占空间,提高了算法速度.文中的实例说明了算法的有效性. 展开更多
关键词 多属性递进网格模型 生成算法 网格顶点 细化序列 网格简化 层次细节模型 CAD/CAM
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基于小波变换和极限学习机的网络流量预测模型 被引量:10
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作者 穆昌 《微型电脑应用》 2020年第1期138-140,共3页
为了提高网络流量预测准确性,结合网络流量的变化特点,针对当前网络流量预测模型存在的局限性,设计了基于小波变换和极限学习机的网络流量预测模型。首先分析了当前国内外网络流量预测研究现状,找到引起网络流量预测准确性差的原因;然... 为了提高网络流量预测准确性,结合网络流量的变化特点,针对当前网络流量预测模型存在的局限性,设计了基于小波变换和极限学习机的网络流量预测模型。首先分析了当前国内外网络流量预测研究现状,找到引起网络流量预测准确性差的原因;然后采用小波变换对原始网络流量时间序列进行去噪,得到无噪声的网络流量时间序列;最后采用极限学习机对网络流量时间序列进行建模,得到相应的预测结果。与当前经典的网络流量预测模型在相同环境下进行对照测试,测试结果分析表明,小波变换和极限学习机的网络流量预测精度达到了95%以上,网络流量预测误差得到了有效的控制,而且提升了网络流量预测效率,预测结果要远优于当前经典的网络流量预测模型。 展开更多
关键词 网络通信系统 流量预测 极限学习机 时间序列数据细化
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SEQUENCE CONSERVATION OF HUMAN CYTOMEGALOVIRUS UL140 OPEN READING FRAME IN CLINICAL STRAINS 被引量:1
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作者 Ying Qi Yan-ping Ma Rong He Zheng-rong Sun Yao-hua Ji Yu-jing Huang Qiang Ruan 《Chinese Medical Sciences Journal》 CAS CSCD 2008年第1期23-27,共5页
Objective To investigate the variability of human cytomegalovirus (HCMV) UL140 open reading flame (ORF) in clinical strains, and to explore the relationship between the variability of UL140 ORF and different sympt... Objective To investigate the variability of human cytomegalovirus (HCMV) UL140 open reading flame (ORF) in clinical strains, and to explore the relationship between the variability of UL140 ORF and different symptoms of HC-MV infection. Methods HCMV UL140 ORF was amplified by polymerase chain reaction and sequenced selectedly in 30 clinical strains. Results UL140 ORF of all clinical strains was amplified successfully. Compared with that of Toledo strain, the nucleotide and amino acid sequence identities among all strains were 96.5% -100.0% and 95.2% -100. 0%, respectively. All of the nucleotide changes were substitutions. The post-translational modification sites were conserved. The result of phylogenetic tree showed that the strains did not cluster according to different clinical symptoms. Conclusion HCMV UL140 ORF in clinical strains is highly conserved, which may play an important role in HC-MV infection. 展开更多
关键词 human cytomegalovirus UL140 CONSERVATION
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Genetic diversity and population structure of Eleutheronema rhadinum in the East and South China Seas revealed in mitochondrial COI sequences 被引量:4
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作者 孙鑫序 徐冬冬 +4 位作者 楼宝 张涛 辛俭 郭垚示 马世磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第6期1276-1283,共8页
Eleutheronema rhadinum is a potential commercial fisheries species and is subject to intense exploitation in China. Knowledge on the population structure of E. rhadinum in Chinese coastal waters, which is important fo... Eleutheronema rhadinum is a potential commercial fisheries species and is subject to intense exploitation in China. Knowledge on the population structure of E. rhadinum in Chinese coastal waters, which is important for sustainable exploitation and proper resource management, is lacking. In the present study, the genetic diversity and population structure of E. rhadinum were evaluated using a 564-base pair fragment of the mitochondrial cytochrome c oxidase subunit I (COl) gene. A total of 76 specimens were collected from three localities around the East (Qidong and Zhoushan) and South China Seas (Zhuhai). Among these individuals, nine polymorphic sites were detected and 1 l distinct haplotypes were defined. High levels ofhaplotype diversity (h=0.759i0.035) and low levels of nucleotide diversity (re=0.001 98i0.003 26) were observed in these populations, Hierarchical analysis of molecular variance (AMOVA) indicated that 96.72% of the genetic variation occurred within the populations, whereas 3.28% occurred among populations. No significant genealogical branches or clusters were recognized on the neighbor-joining tree. Intra-group variation among populations was significant (~0~t=0.032 85, P〈0.01). These results suggest that E. rhadinum populations in the East and South China Seas have developed divergent genetic structures. Tests of neutral evolution and mismatch distribution suggest that E. rhadinum may have experienced a population expansion. The present study provides basic information for the conservation and sustainable exploitation of this species. 展开更多
关键词 Eleutheronema rhadinum cytochrome c oxidase subtmit I (COl) genetic diversity population structure
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Probabilistic Model-Based Silhouette Refinement for Gait Recognition
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作者 张元元 吴晓娟 阮秋琦 《Journal of Shanghai Jiaotong university(Science)》 EI 2010年第1期24-30,共7页
An algorithm to refine and clean gait silhouette noises generated by imperfect motion detection techniques is developed,and a relatively complete and high quality silhouette is obtained.The silhouettes are sequentiall... An algorithm to refine and clean gait silhouette noises generated by imperfect motion detection techniques is developed,and a relatively complete and high quality silhouette is obtained.The silhouettes are sequentially refined in two levels according to two different probabilistic models.The first level is within-sequence refinement.Each silhouette in a particular sequence is refined by an individual model trained by the gait images from current sequence.The second level is between-sequence refinement.All the silhouettes that need further refinement are modified by a population model trained by the gait images chosen from a certain amount of pedestrians.The intention is to preserve the within-class similarity and to decrease the interaction between one class and others.Comparative experimental results indicate that the proposed algorithm is simple and quite effective,and it helps the existing recognition methods achieve a higher recognition performance. 展开更多
关键词 silhouette refinement probabilistic model gait recognition performance evaluation
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