期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
The Principal Component Analysis of Element Contents in Chinese Herbs of the Caine Kidney Mixture
1
作者 Shurong Su Xiaoxi Yang +2 位作者 Yi Xie Weiqun Tian Shirley Z Shen 《Engineering(科研)》 2012年第10期39-42,共4页
Objective: This research compares the nature of 11 kinds of Chinese herbs in the caine kidney mixture, and provides a theoretical way to concentrated prescriptions. Methods: Based on the principal component analysis o... Objective: This research compares the nature of 11 kinds of Chinese herbs in the caine kidney mixture, and provides a theoretical way to concentrated prescriptions. Methods: Based on the principal component analysis of element contents in Chinese herbs, the effects of 25 chemical elements in the 11 kinds of Chinese herbs in the caine kidney mixture have been analyzed. Results: The traditional Chinese medicines of rehmannia, astragalus, mulberry, salvia miltiorrhiza, rhubarb in the caine kidney mixture play a major role in the treatment of chronic renal failure. Conclusion: The principal component analysis is very practical in the compatibility of medicines and concentrated prescriptions. 展开更多
关键词 Chemical ELEMENT Principal com- ponent Analysis the Caine KIDNEY MIXTURE Concentrated PRESCRIPTIONS
暂未订购
孕穗期干旱胁迫对寒地粳稻干物质积累、转运及产量形成影响 被引量:9
2
作者 赵宏伟 田雪飞 +3 位作者 于美芳 沙汉景 贾琰 李艳玲 《东北农业大学学报》 CAS CSCD 北大核心 2016年第11期1-8,共8页
干旱缺水是限制水稻产量主要环境因素之一。为探讨孕穗期干旱胁迫对寒地粳稻干物质积累规律及产量形成影响,选用耐旱型品种东农425和干旱敏感型品种松粳6号为试验材料。通过盆栽结合人工控水方式于孕穗期控制土壤水势至0、-10、-25和-40... 干旱缺水是限制水稻产量主要环境因素之一。为探讨孕穗期干旱胁迫对寒地粳稻干物质积累规律及产量形成影响,选用耐旱型品种东农425和干旱敏感型品种松粳6号为试验材料。通过盆栽结合人工控水方式于孕穗期控制土壤水势至0、-10、-25和-40 k Pa,处理21 d后恢复正常灌溉。研究孕穗期不同程度干旱胁迫对寒地粳稻干物质积累分配转运、产量及产量构成因素影响。结果表明,孕穗期干旱胁迫导致地上部干物质积累量、转运量均随土壤水势降低而下降。成熟期不同器官干物质分配表现为籽粒>茎鞘>叶,茎鞘干物质和源器官干物质分配比例及源/库随干旱程度上升而增加,而籽粒干物质分配比例与其相反。抗旱性强品种在干旱胁迫条件下有较强物质积累优势,贮藏物质转运能力明显高于抗旱性较弱品种。干旱胁迫使枝梗性状下降,对枝梗性状影响表现为二次枝梗>一次枝梗。干旱胁迫下寒地粳稻由于每穴穗数、穗粒数和结实率显著降低造成产量显著下降,降幅随土壤水势降低而逐渐上升。 展开更多
关键词 干旱胁迫 干物质积累 干物质转运 产量 产量构成因素
在线阅读 下载PDF
Genetic Parameters Evaluation of Main Reproductive Traits for the New Yorkshire Dam Line with High Prolificacy
3
作者 宋忠旭 孙华 +3 位作者 彭先文 李良华 董斌科 梅书棋 《Agricultural Science & Technology》 CAS 2013年第10期1465-1467,共3页
The genetic parameters of main reproductive traits for the new Yorkshire line with high prolificacy were evaluated by multiple animal model DFREML The re- suits showed that the heritability evaluates of the total numb... The genetic parameters of main reproductive traits for the new Yorkshire line with high prolificacy were evaluated by multiple animal model DFREML The re- suits showed that the heritability evaluates of the total number of born (TNB), alive number of born (ANB), litter weigh at birth (LWB) and litter weight at age of 21 days were 0.10, 0.15, 0.09 and 0.14, respectively. The genetic correlations between these traits, for example, the correlations between TNB/ANB, NB/LWB, TNB/LW21, ANB/LWB, ANB/LW21 and LWB/LW21 were 0.87, 0.74, 0.43, 0.69, 0.59 and 0.51, respectively. 展开更多
关键词 New Yorkshire dam line with high prolificacy DFREML Variance com- ponent Genetic parameter
在线阅读 下载PDF
Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Stepwise Discriminant Analysis
4
作者 詹军 周芳芳 +5 位作者 董石飞 饶智 朱海滨 资文华 蒋美红 罗华元 《Agricultural Science & Technology》 CAS 2014年第9期1550-1557,共8页
[Objective] The aim of this study was to establish mathematical models for judging the aroma types of middle and upper flue-cured tobacco leaves according to the contents and proportions of aroma compositions. [Method... [Objective] The aim of this study was to establish mathematical models for judging the aroma types of middle and upper flue-cured tobacco leaves according to the contents and proportions of aroma compositions. [Method] The aroma types of tobacco leaves were judged based on stepwise discriminant analysis, using 63 C3F and 65 B2F tobacco leaf samples from 13 tobacco producing regions in 11 provinces of China (Huili in Sichuan, Baokang in Hubei, Wulong in Chongqing, Lu- oyang in Henan, Zhucheng in Shandong, Wuyi Mountain in Fujian, Malong in Yun- nan, Chuxiong in Yunnan, Bijie in Guizhou, Liuyang in Hunan, Suiyang in Guizhou, Kaiyuan in Liaoning, Nanxiong in Guangdong) as calibration samples, and 67 aroma components as indices. And the Fisher discriminant functions were verified using 21 C3F and 19 B2F tobacco leaf samples. [Result] Variation coefficients of the propor- tions were lower than that of contents of most aroma components in middle and upper leaves of the samples, indicating that the proportions were more stable than contents of aroma components. The proportions of benzyl alcohol, solanone, β-dam- ascone, neophytadiene, farnesylacetone A, palmitic acid, thunbergol, methyl linole- nate and cembratriene-diol were all over 1% in both middle and upper leaves, al- though the dominant aroma components of the same aroma type varied between middle and upper leaves. Moreover, 11, 18, 7 and 11 aroma components were re- spectively introduced into the Fisher discriminant functions established based on the contents and proportions of middle and upper flue-cured tobacco leaves, which ex- hibited accuracy rates of 91.7%, 100%, 91.7% and 91.7% in the judgments of other tobacco leaf samples. The results revealed that the components those determined aroma types in middle leaves were obviously more than in upper leaves. In middle leaves, the accuracy rates of aroma type judgment could be improved by using the proportions rather than the contents of aroma components as indices. However, the functions based on the proportions and the contents of aroma components in upper leaves gave close accuracy rates. [Conclusion] The results of the study will provide references for identifying aroma types of flue-cured tobacco leaves in future work. 展开更多
关键词 Flue-cured tobacco leaves Middle leaves Upper leaves Aroma com- ponents Content PROPORTION Aroma type Discriminant analysis
在线阅读 下载PDF
Optimal Feature Extraction Using Greedy Approach for Random Image Components and Subspace Approach in Face Recognition 被引量:3
5
作者 Mathu Soothana S.Kumar Retna Swami Muneeswaran Karuppiah 《Journal of Computer Science & Technology》 SCIE EI CSCD 2013年第2期322-328,共7页
An innovative and uniform framework based on a combination of Gabor wavelets with principal component analysis (PCA) and multiple discriminant analysis (MDA) is presented in this paper. In this framework, features... An innovative and uniform framework based on a combination of Gabor wavelets with principal component analysis (PCA) and multiple discriminant analysis (MDA) is presented in this paper. In this framework, features are extracted from the optimal random image components using greedy approach. These feature vectors are then projected to subspaces for dimensionality reduction which is used for solving linear problems. The design of Gabor filters, PCA and MDA are crucial processes used for facial feature extraction. The FERET, ORL and YALE face databases are used to generate the results. Experiments show that optimal random image component selection (ORICS) plus MDA outperforms ORICS and subspace projection approach such as ORICS plus PCA. Our method achieves 96.25%, 99.44% and 100% recognition accuracy on the FERET, ORL and YALE databases for 30% training respectively. This is a considerably improved performance compared with other standard methodologies described in the literature. 展开更多
关键词 face recognition multiple discriminant analysis optimal random image component selection principal com- ponent analysis recognition accuracy
原文传递
THE FAST FIXED-POINT ALGORITHM FOR SPECKLE REDUCTION OF POLARIMETRIC SAR IMAGE
6
作者 FuYusheng ChertXiaoning PiYiming HouYinming 《Journal of Electronics(China)》 2005年第3期288-293,共6页
In this letter, a simple and efficient method of image speckle reduction for polari- metric SAR is put forward. It is based on the fast fixed-point ICA (Independent Component Analysis) algorithm of orthogonal and symm... In this letter, a simple and efficient method of image speckle reduction for polari- metric SAR is put forward. It is based on the fast fixed-point ICA (Independent Component Analysis) algorithm of orthogonal and symmetric matrix. Simulation experiment is carried out to separate speckle noise from the polarimetric SAR images, and it indicates that this algorithm has high convergency speed and stability, the image speckle noise is reduced effectively and the speckle index is low, and the image quality is improved obviously. 展开更多
关键词 SAR Fast fixed-point Independent Component Analysis (ICA) Principal com- ponent Analysis (PCA) KURTOSIS SPECKLE
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部