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两种光谱混合分析模型的比较 被引量:2
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作者 王钦军 蔺启忠 +1 位作者 黎明晓 王黎明 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2009年第10期2602-2605,共4页
为了分析与对比线性光谱混合分析模型(LSMA)和约束线性光谱混合分析模型(CLSMA)在光谱混合分解中的优势与劣势,我们设计了混合光谱分解实验。反演结果表明,当利用所有光谱数据进行端元百分含量反演时,LSMA的总误差比CLSMA小0.075。当利... 为了分析与对比线性光谱混合分析模型(LSMA)和约束线性光谱混合分析模型(CLSMA)在光谱混合分解中的优势与劣势,我们设计了混合光谱分解实验。反演结果表明,当利用所有光谱数据进行端元百分含量反演时,LSMA的总误差比CLSMA小0.075。当利用波段选择后的数据进行端元百分含量反演时,前者的总误差比后者小0.017。这样,不论是利用所有光谱波段数据还是利用波段选择后的数据,LSMA在混合光谱分解的效果上都优于CLSMA;此外,LSMA利用波段选择数据反演端元百分含量的总误差比它利用所有波段数据的总误差小0.02,CLSMA利用波段选择数据反演端元百分含量的总误差比它用所有波段数据的总误差小0.077。这主要是因为波段选择大大减少了端元光谱间的相关性,所以,利用波段选择数据进行混合光谱分解优于不加选择的光谱混合分解。 展开更多
关键词 线性光谱混合分析模型 约束线性光谱混合分析模型 遥感
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影响课堂教学质量评价因素的混合线性模型分析 被引量:1
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作者 刘宾 段涛 闫秀娟 《中医药管理杂志》 2019年第7期19-21,共3页
目的:运用数据挖掘技术对学生评教信息进行分析,探讨影响教学质量的关键因素,为正确评估教学行为、分析教学状态,制定正确的教学管理政策提供依据。方法:采集2016年6月406位教师的学生评教数据,运用混合线性模型,探求影响评教结果的关... 目的:运用数据挖掘技术对学生评教信息进行分析,探讨影响教学质量的关键因素,为正确评估教学行为、分析教学状态,制定正确的教学管理政策提供依据。方法:采集2016年6月406位教师的学生评教数据,运用混合线性模型,探求影响评教结果的关键因素。结果:不同部门教师的评教成绩存在聚集性;年龄结构是教师评教成绩在"所属部门"中存在聚集性的主要因素。结论:年轻教师的教学质量总体较好,但年轻教师之间的教学质量存在显著差异。应进一步强化年轻教师对教学基本技能的掌握,提高年轻教师的教学组织能力,提高教学质量。 展开更多
关键词 学生评教 混合线性模型分析 教学质量评价
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桑枝粗细对枝条叶片养分分配比例的影响
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作者 王谢 张建华 +5 位作者 林超文 庞良玉 姚莉 刘海涛 朱永群 许文志 《中国蚕业》 2018年第3期1-4,共4页
通过探明新生桑树叶片和枝条内的养分分配比例与桑枝粗细之间的关系,揭示不同粗细桑树枝条的叶片和枝条的干物质、矿物质养分分配规律,为桑叶或桑枝原材料的选择利用提供参考依据。以农桑14号为研究材料,在雾化栽培的条件下研究叶片和... 通过探明新生桑树叶片和枝条内的养分分配比例与桑枝粗细之间的关系,揭示不同粗细桑树枝条的叶片和枝条的干物质、矿物质养分分配规律,为桑叶或桑枝原材料的选择利用提供参考依据。以农桑14号为研究材料,在雾化栽培的条件下研究叶片和枝条间干物质和N、P、K、Ca、Mg、Cu、Zn、Fe、Mn、S、B、Mo和Cl等13种矿物质养分对桑树枝条粗细的响应情况。试验结果表明:桑树K、Ca、Mg、Zn和Mn在叶片和枝条的分配比例不受桑树枝条粗细的影响,而细枝条上的叶片在干物质和N、P、Cu、Fe、S、B、Mo与Cl等矿物质养分的分配上具有显著的优势。 展开更多
关键词 桑树 桑枝 微量元素 干物质 相关性分析 线性混合模型分析 药理作用
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Improvement of Urban Impervious Surface Estimation in Shanghai Using Landsat7 ETM+ Data 被引量:7
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作者 YUE Wenze 《Chinese Geographical Science》 SCIE CSCD 2009年第3期283-290,共8页
This paper explores the potential to improve the impervious surface estimation accuracy using a multi-stage approach on the basis of vegetation-impervious surface-soil (V-I-S) model. In the first stage of Spectral Mix... This paper explores the potential to improve the impervious surface estimation accuracy using a multi-stage approach on the basis of vegetation-impervious surface-soil (V-I-S) model. In the first stage of Spectral Mixture Analysis (SMA) process, pixel purity index, a quantitative index for defining endmember quality, and a 3-dimensional endmember selection method were applied to refining endmembers. In the second stage, instead of obtaining impervious surface fraction by adding high and low albedo fractions directly, a linear regression model was built between impervious surface and high/low albedo using a random sampling method. The urban impervious surface distribution in the urban central area of Shanghai was predicted by the linear regression model. Estimation accuracy of spectral mixture analysis and impervious surface fraction were assessed using root mean square (RMS) and color aerial photography respectively. In comparison with three different research methods, this improved estimation method has a higher overall accuracy than traditional Linear Spectral Mixture Analysis (LSMA) method and the normalized SMA model both in root mean square error (RMSE) and standard error (SE). However, the model has a tendency to overestimate the impervious surface distribution. 展开更多
关键词 vegetation-impervious surface-soil model spectral mixture analysis impervious surface SHANGHAI
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Comparison of wrist motion classification methods using surface electromyogram 被引量:1
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作者 JEONG Eui-chul KIM Seo-jun +1 位作者 SONG Young-rok LEE Sang-min 《Journal of Central South University》 SCIE EI CAS 2013年第4期960-968,共9页
The Gaussian mixture model (GMM), k-nearest neighbor (k-NN), quadratic discriminant analysis (QDA), and linear discriminant analysis (LDA) were compared to classify wrist motions using surface electromyogram (EMG). Ef... The Gaussian mixture model (GMM), k-nearest neighbor (k-NN), quadratic discriminant analysis (QDA), and linear discriminant analysis (LDA) were compared to classify wrist motions using surface electromyogram (EMG). Effect of feature selection in EMG signal processing was also verified by comparing classification accuracy of each feature, and the enhancement of classification accuracy by normalization was confirmed. EMG signals were acquired from two electrodes placed on the forearm of twenty eight healthy subjects and used for recognition of wrist motion. Features were extracted from the obtained EMG signals in the time domain and were applied to classification methods. The difference absolute mean value (DAMV), difference absolute standard deviation value (DASDV), mean absolute value (MAV), root mean square (RMS) were used for composing 16 double features which were combined of two channels. In the classification methods, the highest accuracy of classification showed in the GMM. The most effective combination of classification method and double feature was (MAV, DAMV) of GMM and its classification accuracy was 96.85%. The results of normalization were better than those of non-normalization in GMM, k-NN, and LDA. 展开更多
关键词 Gaussian mixture model k-nearest neighbor quadratic discriminant analysis linear discriminant analysis electromyogram (EMG) pattern classification feature extraction
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Linear Mixed Model Analysis of Worldwide Longitudinal Infant Mortality Rate Data and Association with Human Development Index
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作者 Serpil Aktas 《Journal of Mathematics and System Science》 2013年第4期173-179,共7页
A linear mixed model is used to determine the explaining infant mortality rate data of United Nations countries. The HDI (human development index) has a significant negative linear relationship with infant mortality... A linear mixed model is used to determine the explaining infant mortality rate data of United Nations countries. The HDI (human development index) has a significant negative linear relationship with infant mortality rate. United Nations data shows that the infant mortality rate has a descending trend over the period 1990-2010. This study aims to assess the value of the HDI as a predictor of infant mortality rate. Findings in the paper suggest that significant percentage reductions in infant mortality might be possible for countries for controlling the HDI. 展开更多
关键词 Infant mortality rate human development index linear mixed models
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