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竞技跆拳道腿法技术体系家族图谱及其衍生分类研究 被引量:2
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作者 龚循谦 赖江萍 龚循磊 《景德镇学院学报》 2016年第3期91-94,98,共5页
传统的跆拳道教材或资料都认为跆拳道的腿法技术由7种基本腿法构成,它们由前踢、横踢、下劈、推踢、后踢、旋转踢、后旋踢组成。笔者认为传统的跆拳道腿法技术体系的分类存在许多不足,比如各种腿法之间的关系不清楚,脉络也不清晰等。笔... 传统的跆拳道教材或资料都认为跆拳道的腿法技术由7种基本腿法构成,它们由前踢、横踢、下劈、推踢、后踢、旋转踢、后旋踢组成。笔者认为传统的跆拳道腿法技术体系的分类存在许多不足,比如各种腿法之间的关系不清楚,脉络也不清晰等。笔者通过十五年的一线带队训练的总结,查阅了大量的资料,访谈了许多跆拳道专家,发现跆拳道各种腿法技术之间存在着联系,而且是家族式的关系。本文将通过表格的形式将跆拳道腿法的家族图谱清晰地展现给大家,并且尽可能地描述各腿法家族的特征。 展开更多
关键词 跆拳道 腿法分类 腿法分类图谱
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基于放电图谱仿真的局部放电检测仪性能评估方法及系统研制 被引量:3
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作者 胡岳 Chiampi M +1 位作者 Crotti G 张千千 《电气工程学报》 2015年第5期87-93,共7页
提出了一种基于放电图谱物理仿真的局部放电检测仪性能评估方法,并开发了一套评估系统。系统从现场检测、模拟试验和数字仿真三种途径收集典型放电图谱并形成数据库。参考局部放电校准仪结构,基于可编程波形发生模块构建了局部放电脉冲... 提出了一种基于放电图谱物理仿真的局部放电检测仪性能评估方法,并开发了一套评估系统。系统从现场检测、模拟试验和数字仿真三种途径收集典型放电图谱并形成数据库。参考局部放电校准仪结构,基于可编程波形发生模块构建了局部放电脉冲序列物理仿真系统,仿真输出数据库中的典型局部放电图谱,用以评估数字局放仪诸如放电类型模式识别等高级功能。本文对所研发系统的结构和其产生脉冲序列的特征进行了详细阐述,系统在数字式局部放电测量仪器上的应用案例表明了该评估系统的应用前景。 展开更多
关键词 性能评估系统 校准 局部放电 数字式局放仪 图谱分类
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特征图谱时频信号放电识别算法研究与现场应用 被引量:6
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作者 周雄 周泽民 +2 位作者 彭彦军 滕本科 唐明 《电气技术》 2020年第6期63-68,87,共7页
高压电气设备局部放电检测通常夹杂干扰信号,造成分析与判断困难,干扰信号抑制是局部放电识别和故障判断的前提。基于局部放电信号时频分布特征,采用等效持续时间T和等效频率带宽F来表征局部放电宽带脉冲波形的时频特征,构建等效时频特... 高压电气设备局部放电检测通常夹杂干扰信号,造成分析与判断困难,干扰信号抑制是局部放电识别和故障判断的前提。基于局部放电信号时频分布特征,采用等效持续时间T和等效频率带宽F来表征局部放电宽带脉冲波形的时频特征,构建等效时频特征图谱(T-F谱图),再进行聚类分析即可实现不同放电类型和噪声的分离。利用特征图谱分类法对高压开关柜局部放电信号进行噪声抑制与脉冲分类,验证该方法对局部放电混合信号分离的有效性。 展开更多
关键词 局部放电 特征提取 特征图谱分类
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焊缝缺陷超声相控阵全聚焦图谱敏感辨识特征集研究
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作者 刘文婧 成博 +1 位作者 王建国 王少锋 《内蒙古科技大学学报》 CAS 2022年第3期237-243,共7页
针对焊缝超声相控阵检测全聚焦图谱中特征描述能力较弱的问题,提出一种基于敏感辨识特征集的缺陷表示方法.该方法首先结合焊缝缺陷特点和超声相控阵全聚焦图谱生成原理,从图谱颜色分布、缺陷形貌和区域纹理细节三方面构建特征描述集合;... 针对焊缝超声相控阵检测全聚焦图谱中特征描述能力较弱的问题,提出一种基于敏感辨识特征集的缺陷表示方法.该方法首先结合焊缝缺陷特点和超声相控阵全聚焦图谱生成原理,从图谱颜色分布、缺陷形貌和区域纹理细节三方面构建特征描述集合;然后将传统缺陷识别中五分类模型转化为多个二分类模型,采用缺陷特征敏感度和特征相关性作为评价准则,构建缺陷的敏感辨识特征集.实验结果表明:敏感辨识特征集对缺陷特征的描述能力更强,有效降低了单一特征集中冗余特征的影响,具有良好的可区分性,有助于缺陷分类识别. 展开更多
关键词 超声相控阵 全聚焦图谱 敏感特征集 图谱分类
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Genetic Diversity Analysis and Fingerprint Construction of Major Mango Cultivars in China 被引量:1
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作者 王明 应东山 +2 位作者 王琴飞 李莉萍 张如莲 《Agricultural Science & Technology》 CAS 2016年第6期1289-1294,共6页
[Objective] The genetic diversity of major mango cultivars in China was analyzed by using SSR markers, and their fingerprints were constructed so as to provide theoretical basis for germplasm innovation and breeding o... [Objective] The genetic diversity of major mango cultivars in China was analyzed by using SSR markers, and their fingerprints were constructed so as to provide theoretical basis for germplasm innovation and breeding of mango. [Method] With 115 pairs of SSR primers, genetic diversity analysis and cluster analysis were performed for 30 mango cultivars, among which the genetic relationships were analyzed. [Result] Total 64 pairs of polymorphic primers were screened out from the 115 pairs of primers, and total 343 bands were amplified from the 30 cultivars with 73.2% of polymorphic bands. On average, 3.9 allelic loci were detected for each pair of primers with genetic diversity index of 0.5, Shannon's diversity index of 1.00 and polymorphism information content of 0.49, indicating higher genetic diversity. The cluster analysis showed that the 30 major cultivars could be classified into four categories. The first category included 14 cultivars; the second category included 11 cultivars, most of which were introduced from abroad; the third category included 4 cultivars, Le., Miansan, Parayinda, Baiyu and Hongxiangya: the fourth category included only one cultivar Maqiesu.By using 7 pairs of SSR markers, i.e., M42, M49, M54, M55, M96, M99 and M103, digital fingerprints were constructed for the 30 mango cultivars. [Conclusion] The 30 mango cultivars present more complex genomic genetics and abundant genetic information, and they have higher genetic diversity. 展开更多
关键词 MANGO Major cultivar SSR marker Cluster analysis FINGERPRINT
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肠道微生物测序研究中不同实验来源差异的综合评价以及应用 被引量:1
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作者 徐珂琳 庄悦 +8 位作者 朱嗣博 薛江莉 蒋艳峰 袁子宇 王久存 索晨 张铁军 吕明 陈兴栋 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2022年第7期959-970,共12页
肠道微生物测序研究具有将微生物结果转化为人类健康的巨大潜力。16S扩增子测序和宏基因组鸟枪测序(whole-metagenome shotgun,WMS)是微生物组研究中的两大主要方法,各具优势。然而,研究样品的异质性、测序仪和文库制备方法的差异如何... 肠道微生物测序研究具有将微生物结果转化为人类健康的巨大潜力。16S扩增子测序和宏基因组鸟枪测序(whole-metagenome shotgun,WMS)是微生物组研究中的两大主要方法,各具优势。然而,研究样品的异质性、测序仪和文库制备方法的差异如何影响肠道微生物测序结果的可重复性仍有待深入研究。该研究旨在通过比较粪便样本中微生物组成的差异,为测序技术的选择提供参考标准。3种广泛采用的测序仪的结果显示,WMS法中技术重复相关性(r=0.94)较高,而生物学重复相关性(r=0.69)较低。Bray-Curtis距离表明,生物学重复的差异大于技术重复(P<0.001)。此外,16S和WMS数据集间具有明显的分类学图谱差异。研究结果表明,同质化是样品DNA提取前的一个必要步骤;测序仪对分类学变异的贡献小于文库制备方法。我们开发了经验贝叶斯方法,即在计算中“借用信息”,利用标准化数据和(非)参数先验分布分析批次效应参数,提高了16S和WMS之间的群体可比性,为进一步应用于融合分析已发表的16S和微生物数据集提供了依据。 展开更多
关键词 肠道微生物测序 16S扩增子测序 宏基因组鸟枪测序 分类图谱 经验贝叶斯
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美军作战仿真系统综述 被引量:20
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作者 唐忠 薛永奎 刘丽 《航天电子对抗》 2014年第4期45-48,52,共5页
电子信息装备是武器装备体系的中枢,作战仿真技术是评估装备作战效能、提升部队作战训练效果的重要手段。以处于世界领先地位的美军作战仿真系统为研究对象,从介绍美军仿真的分类图谱、分析其技术体系发展过程入手,重点阐述了美军典型... 电子信息装备是武器装备体系的中枢,作战仿真技术是评估装备作战效能、提升部队作战训练效果的重要手段。以处于世界领先地位的美军作战仿真系统为研究对象,从介绍美军仿真的分类图谱、分析其技术体系发展过程入手,重点阐述了美军典型联合作战仿真系统的功能定位、组成及应用情况,介绍了美军作战仿真系统的成功经验及其技术局限性。 展开更多
关键词 仿真 仿真分类图谱 作战仿真系统 电子战
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Feature extraction for target identification and image classification of OMIS hyperspectral image 被引量:7
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作者 DU Pei-jun TAN Kun SU Hong-jun 《Mining Science and Technology》 EI CAS 2009年第6期835-841,共7页
In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree alg... In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree algorithm,spectral absorption index (SAI),continuum-removal and derivative spectral analysis were employed to discover characterized spectral features of different targets,and decision trees for identifying a specific class and discriminating different classes were generated. By combining support vector machine (SVM) classifier with different feature extraction strategies including principal component analysis (PCA),minimum noise fraction (MNF),grouping PCA,and derivate spectral analysis,the performance of feature extraction approaches in classification was evaluated. The results show that feature extraction by PCA and derivate spectral analysis are effective to OMIS (operational modular imaging spectrometer) image classification using SVM,and SVM outperforms traditional SAM and MLC classifiers for OMIS data. 展开更多
关键词 hyperspectral remote sensing feature extraction decision tree SVM OMIS
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Classification of hyperspectral remote sensing images based on simulated annealing genetic algorithm and multiple instance learning 被引量:3
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作者 高红民 周惠 +1 位作者 徐立中 石爱业 《Journal of Central South University》 SCIE EI CAS 2014年第1期262-271,共10页
A hybrid feature selection and classification strategy was proposed based on the simulated annealing genetic algonthrn and multiple instance learning (MIL). The band selection method was proposed from subspace decom... A hybrid feature selection and classification strategy was proposed based on the simulated annealing genetic algonthrn and multiple instance learning (MIL). The band selection method was proposed from subspace decomposition, which combines the simulated annealing algorithm with the genetic algorithm in choosing different cross-over and mutation probabilities, as well as mutation individuals. Then MIL was combined with image segmentation, clustering and support vector machine algorithms to classify hyperspectral image. The experimental results show that this proposed method can get high classification accuracy of 93.13% at small training samples and the weaknesses of the conventional methods are overcome. 展开更多
关键词 hyperspectral remote sensing images simulated annealing genetic algorithm support vector machine band selection multiple instance learning
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China's Wetland Databases Based on Remote Sensing Technology 被引量:4
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作者 YAN Fengqin LIU Xingtu +5 位作者 CHEN Jing YU Lingxue YANG Chaobin CHANG Liping YANG Jiuchun ZHANG Shuwen 《Chinese Geographical Science》 SCIE CSCD 2017年第3期374-388,共15页
Wetland databases can provide the basic data that necessary for the protection and management of wetlands. A large number of wetland databases have been established in the world as well as in China. In this paper, we ... Wetland databases can provide the basic data that necessary for the protection and management of wetlands. A large number of wetland databases have been established in the world as well as in China. In this paper, we review China's wetland databases based on remote sensing(RS) technology after introducing the background theory to the application of RS technology in wetland surveys. A key conclusion is that China's wetland databases are far from sufficient in fulfilling protection and management needs. Our recommendations focus on the use of the hyper-spectral imagery, microwave data, multi-temporal images, and automatic classifications in order to improve the accuracy and efficiency of wetland inventory. Further, attention should also be paid to detect major biophysical features of wetlands and build wetland databases in years after the 1980 s in China. Considering that great gap exists between RS experts and wetland experts, further cooperation between wetland scientists and RS scientists are needed to promote the application of RS in the foundation of wetland databases. 展开更多
关键词 wetlands inventory remote sensing mapping China
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Automated Classification of Segmented Cancerous Cells in Multispectral Images
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作者 Alaa Hilal Jamal Charara Ali Al Houseini Walid Hassan Mohamad Nassreddine 《Journal of Life Sciences》 2013年第4期358-362,共5页
Automatic reading procedures in colon cells biopsies allow a faster and precise reading of microscopic biopsies. These procedures implement automatic image segmentation in order to classify cell types as cancerous or ... Automatic reading procedures in colon cells biopsies allow a faster and precise reading of microscopic biopsies. These procedures implement automatic image segmentation in order to classify cell types as cancerous or noncancerous. The authors have developed a new approach aiming to detect colon cancer cells derived from the "Snake" method but using a progressive division of the dimensions of the image to achieve rapid segmentation. The aim of the present paper was to classify different cancerous cell types based on nine morphological parameters and on probabilistic neural network. Three types of cells were used to assess the efficiency of our classifications models, including BH (Benign Hyperplasia), IN (Intraepithelial Neoplasia) that is a precursor state for cancer, and Ca (Carcinoma) that corresponds to abnormal tissue proliferation (cancer). Results showed that among the nine parameters used to classify cells, only three morphologic parameters (area, Xor convex and solidity) were found to be effective in distinguishing the three types of cells. In addition, classification of unknown cells was possible using this method. 展开更多
关键词 Multispectral image CLASSIFICATION morphologic parameters probabilistic neural network.
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基于意图和情感的南海学术论文引用特征研究 被引量:3
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作者 齐小英 李昕尉 杨海平 《数据分析与知识发现》 CSSCI CSCD 北大核心 2022年第12期53-69,共17页
【目的】分析南海学术论文的引用意图和引用情感,揭示学者的引用行为与学术思想涌现过程。【方法】建立引文分类体系,采用基于特征的支持向量机实现引文自动分类,基于知识图谱构建引文分类图谱,从总体分布、国家差异、引用主题三个方面... 【目的】分析南海学术论文的引用意图和引用情感,揭示学者的引用行为与学术思想涌现过程。【方法】建立引文分类体系,采用基于特征的支持向量机实现引文自动分类,基于知识图谱构建引文分类图谱,从总体分布、国家差异、引用主题三个方面分析南海学术论文的引用特征。【结果】引用意图和引用情感自动分类的F1宏平均值分别为0.75和0.72。中国学者倾向从历史视角维护南海主权,引用的意图主要作为“使用”和“背景”引用,引用的情感主要作为“中性”引用。【局限】语料数据规模较小,数据源的全面性有待加强。【结论】中国学者从历史视角维护南海主权的同时,也要加强从法理视角论证南海争议主题。 展开更多
关键词 引用意图 引用情感 引文分类 引文分类图谱 南海
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High-resolution remote sensing mapping of global land water 被引量:26
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作者 LIAO AnPing CHEN LiJun +6 位作者 CHEN Jun HE ChaoYing CAO Xin CHEN Jin PENG Shu SUN FangDi GONG Peng 《Science China Earth Sciences》 SCIE EI CAS 2014年第10期2305-2316,共12页
Land water, one of the important components of land cover, is the indispensable and important basic information for climate change studies, ecological environment assessment, macro-control analysis, etc. This article ... Land water, one of the important components of land cover, is the indispensable and important basic information for climate change studies, ecological environment assessment, macro-control analysis, etc. This article describes the overall study on land water in the program of global land cover remote sensing mapping. Through collection and processing of Landsat TM/ETM+, China's HJ-1 satellite image, etc., the program achieves an effective overlay of global multi-spectral image of 30 m resolution for two base years, namely, 2000 and 2010, with the image rectification accuracy meeting the requirements of 1:200000 mapping and the error in registration of images for the two periods being controlled within 1 pixel. The indexes were designed and selected reasonably based on spectral features and geometric shapes of water on the scale of 30 m resolution, the water information was extracted in an elaborate way by combining a simple and easy operation through pixel-based classification method with a comprehensive utilization of various rules and knowledge through the object-oriented classification method, and finally the classification results were further optimized and improved by the human-computer interaction, thus realizing high-resolution remote sensing mapping of global water. The completed global land water data results, including Global Land 30-water 2000 and Global Land 30-water 2010, are the classification results featuring the highest resolution on a global scale, and the overall accuracy of self-assessment is 96%. These data are the important basic data for developing relevant studies, such as analyzing spatial distribution pattern of global land water, revealing regional difference, studying space-time fluctuation law, and diagnosing health of ecological environment. 展开更多
关键词 global land cover land surface water 30 m resolution classification method remote sensing mapping
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Genomic landscape of gastric cancer: molecular classification and potential targets 被引量:6
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作者 Jiawei Guo Weiwei Yu +1 位作者 Hui Su Xiufeng Pang 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第2期126-137,共12页
Gastric cancer imposes a considerable health burden worldwide, and its mortality ranks as the second highest for all types of cancers. The limited knowledge of the molecular mechanisms underlying gastric cancer tumori... Gastric cancer imposes a considerable health burden worldwide, and its mortality ranks as the second highest for all types of cancers. The limited knowledge of the molecular mechanisms underlying gastric cancer tumorigenesis hinders the development of therapeutic strategies. However, ongoing collaborative sequencing efforts facilitate molecular classification and unveil the genomic landscape of gastric cancer. Several new drivers and tumorigenic pathways in gastric cancer, including chromatin remodeling genes, Rho A-related pathways, TP53 dysregulation, activation of receptor tyrosine kinases, stem cell pathways and abnormal DNA methylation, have been revealed. These newly identified genomic alterations await translation into clinical diagnosis and targeted therapies. Considering that loss-of-function mutations are intractable, synthetic lethality could be employed when discussing feasible therapeutic strategies. Although many challenges remain to be tackled, we are optimistic regarding improvements in the prognosis and treatment of gastric cancer in the near future. 展开更多
关键词 gastric cancer chromatin remodeling RHOA p53 receptor tyrosine kinase DNA methylation
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Classification of hyperspectral remote sensing images using frequency spectrum similarity 被引量:10
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作者 WANG Ke GU XingFa +3 位作者 YU Tao MENG QingYan ZHAO LiMin FENG Li 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第4期980-988,共9页
An algorithm of hyperspectral remote sensing images classification is proposed based on the frequency spectrum of spectral signature.The spectral signature of each pixel in the hyperspectral image is taken as a discre... An algorithm of hyperspectral remote sensing images classification is proposed based on the frequency spectrum of spectral signature.The spectral signature of each pixel in the hyperspectral image is taken as a discrete signal,and the frequency spectrum is obtained using discrete Fourier transform.The discrepancy of frequency spectrum between ground objects' spectral signatures is visible,thus the difference between frequency spectra of reference and target spectral signature is used to measure the spectral similarity.Canberra distance is introduced to increase the contribution from higher frequency components.Then,the number of harmonics involved in the proposed algorithm is determined after analyzing the frequency spectrum energy cumulative distribution function of ground object.In order to evaluate the performance of the proposed algorithm,two hyperspectral remote sensing images are adopted as experimental data.The proposed algorithm is compared with spectral angle mapper (SAM),spectral information divergence (SID) and Euclidean distance (ED) using the product accuracy,user accuracy,overall accuracy,average accuracy and Kappa coefficient.The results show that the proposed algorithm can be applied to hyperspectral image classification effectively. 展开更多
关键词 hyperspectral image spectral similarity frequency spectrum feature remote sensing CLASSIFICATION
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