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A Quantitative DFA Method Based on Neural Network and Function Analysis
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作者 顾廷权 高国安 卞瑞花 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第4期15-18,共4页
In this paper, a new systematic methed of quantitative DFA is presented based on the function analysis.The reduction of the number of components forming product is realized by incorporating some parts as the features ... In this paper, a new systematic methed of quantitative DFA is presented based on the function analysis.The reduction of the number of components forming product is realized by incorporating some parts as the features of others. In order to evaluate assemblability of a product objectively, accurately and completely, the factors affecting assembability have been identified in terms of the production mode used to assemble product, and neural network and fuzzy set theory are adopted to quantify the effect of factors on assemblability. A case study is given, and the results demonstrate the effectiveness and validity of the method. 展开更多
关键词 dfa ASSEMBLABILITY NEURAL network function analysis FUZZY SET theory
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SPEECH EMOTION RECOGNITION USING MODIFIED QUADRATIC DISCRIMINATION FUNCTION 被引量:9
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作者 Zhao Yan Zhao Li Zou Cairong Yu Yinhua 《Journal of Electronics(China)》 2008年第6期840-844,共5页
Quadratic Discrimination Function (QDF) is commonly used in speech emotion recognition, which proceeds on the premise that the input data is normal distribution. In this paper, we propose a transformation to normali... Quadratic Discrimination Function (QDF) is commonly used in speech emotion recognition, which proceeds on the premise that the input data is normal distribution. In this paper, we propose a transformation to normalize the emotional features, emotion recognition. Features based on prosody then derivate a Modified QDF (MQDF) to speech and voice quality are extracted and Principal Component Analysis Neural Network (PCANN) is used to reduce dimension of the feature vectors. The results show that voice quality features are effective supplement for recognition, and the method in this paper could improve the recognition ratio effectively. 展开更多
关键词 Speech emotion recognition Principal Component analysis Neural Network (PCANN) Modified Quadratic discrimination function (MQDF)
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Functional Data Analysis of Spectroscopic Data with Application to Classification of Colon Polyps
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作者 Ying Zhu 《American Journal of Analytical Chemistry》 2017年第4期294-305,共12页
In this study, two functional logistic regression models with functional principal component basis (FPCA) and functional partial least squares basis (FPLS) have been developed to distinguish precancerous adenomatous p... In this study, two functional logistic regression models with functional principal component basis (FPCA) and functional partial least squares basis (FPLS) have been developed to distinguish precancerous adenomatous polyps from hyperplastic polyps for the purpose of classification and interpretation. The classification performances of the two functional models have been compared with two widely used multivariate methods, principal component discriminant analysis (PCDA) and partial least squares discriminant analysis (PLSDA). The results indicated that classification abilities of FPCA and FPLS models outperformed those of the PCDA and PLSDA models by using a small number of functional basis components. With substantial reduction in model complexity and improvement of classification accuracy, it is particularly helpful for interpretation of the complex spectral features related to precancerous colon polyps. 展开更多
关键词 functionAL Principal COMPONENT analysis functionAL PARTIAL Least SQUARES functionAL Logistic Regression Principal COMPONENT discriminANT analysis PARTIAL Least SQUARES discriminANT analysis
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Functional Analysis of Chemometric Data
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作者 Ana M. Aguilera Manuel Escabias +1 位作者 Mariano J. Valderrama M. Carmen Aguilera-Morillo 《Open Journal of Statistics》 2013年第5期334-343,共10页
The objective of this paper is to present a review of different calibration and classification methods for functional data in the context of chemometric applications. In chemometric, it is usual to measure certain par... The objective of this paper is to present a review of different calibration and classification methods for functional data in the context of chemometric applications. In chemometric, it is usual to measure certain parameters in terms of a set of spectrometric curves that are observed in a finite set of points (functional data). Although the predictor variable is clearly functional, this problem is usually solved by using multivariate calibration techniques that consider it as a finite set of variables associated with the observed points (wavelengths or times). But these explicative variables are highly correlated and it is therefore more informative to reconstruct first the true functional form of the predictor curves. Although it has been published in several articles related to the implementation of functional data analysis techniques in chemometric, their power to solve real problems is not yet well known. Because of this the extension of multivariate calibration techniques (linear regression, principal component regression and partial least squares) and classification methods (linear discriminant analysis and logistic regression) to the functional domain and some relevant chemometric applications are reviewed in this paper. 展开更多
关键词 functionAL Data analysis B-SPLINES functionAL Principal Component Regression functionAL Partial Least SQUARES functionAL LOGIT Models functionAL Linear discriminANT analysis Spectroscopy NIR Spectra
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基于改进DFA和LDA的永磁同步电机机械故障检测 被引量:7
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作者 赵嗣芳 宋强 +1 位作者 张艳明 张伟 《北京理工大学学报》 EI CAS CSCD 北大核心 2023年第1期61-69,共9页
为提高故障检测的精度,研究了变转速工况下永磁同步电机的机械故障检测方法.首先,分析了电机轴承、转子偏心及其复合故障的振动特性;其次,采用Vold-Kalman算法对故障特征分量进行跟踪提取,并通过信号重构消除转速变化对故障特征分量的影... 为提高故障检测的精度,研究了变转速工况下永磁同步电机的机械故障检测方法.首先,分析了电机轴承、转子偏心及其复合故障的振动特性;其次,采用Vold-Kalman算法对故障特征分量进行跟踪提取,并通过信号重构消除转速变化对故障特征分量的影响;提出一种基于改进去趋势波动分析和线性判别式分析的机械故障检测方法,实现对重构信号的故障特征提取和故障检测;最后,对所提出故障检测方法的有效性进行实验验证.实验结果表明文中所提出方法的故障检测精度为88%. 展开更多
关键词 永磁同步电机 机械故障 故障检测 去趋势波动分析 线性判别式分析
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Wave height statistical characteristic analysis 被引量:4
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作者 LIU Guilin CHEN Baiyu +3 位作者 WANG Liping ZHANG Shuaifang ZHANG Kuangyuan LEI Xi 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期448-460,共13页
When exploring the temporal and spatial change law of ocean environment, the most common method used is using smaller-scale observed data to derive the change law for a larger-scale system. For instance, using 30-year... When exploring the temporal and spatial change law of ocean environment, the most common method used is using smaller-scale observed data to derive the change law for a larger-scale system. For instance, using 30-year observation data to derive 100-year return period design wave height. Therefore, the study of inherent self-similarity in ocean hydrological elements becomes increasingly important to the study of multi-year return period design wave height derivation. In this paper, we introduced multifractal to analyze the statistical characteristics of wave height series data observed from oceanic hydrological station. An improvement is made to address the existing problems of the multifractal detrended fluctuation analysis (MF-DFA) method, where trend function showed a discontinuity between intervals. The improved MFDFA method is based on signal mode decomposition, replacing piecewise polynomial fitting used in the original method. We applied the proposed method to the wave height data collected at Chaolian Island, Shandong, China, from 1963 to 1989 and was able to conclude the wave height sequence presented weak multi-fractality. This result provided strong support to the past research on the derivation of multi-year return period design wave height with observed data. Moreover, the new method proposed in this paper also provides a new perspective to explore the intrinsic characteristic of data. 展开更多
关键词 wave HEIGHT PARTITION function MULTIFRACTAL spectrum MULTIFRACTAL detrended FLUCTUATION analysis (MF-dfa) signal mode DECOMPOSITION
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Morphometric discrimination between females of two isomorphic sand fly species, Phlebotomus caucasicus and Phlebotomus mongolensis(Diptera:Phlebotominae) in endemic and non-endemic foci of zoonotic cutaneous leishmaniasis in Iran
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作者 Azad Absavaran Mehdi Mohebali +5 位作者 Vahideh Moin-Vaziri Alireza Zahraei-Ramazani Amir Ahmad Akhavan Fariba Mozaffarian Sayena Rafizadeh Yavar Rassi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2019年第4期153-162,共10页
Objective: To delineate reliable morphological characteristics for identifying and separating female Phlebotomus caucasicus and Phlebotomus mongolensis which exist sympatrically in the main foci of zoonotic cutaneous ... Objective: To delineate reliable morphological characteristics for identifying and separating female Phlebotomus caucasicus and Phlebotomus mongolensis which exist sympatrically in the main foci of zoonotic cutaneous leishmaniasis in Iran.Methods: Sand flies were collected using sticky trap papers from active colonies of rodent burrows installed from 16 catching sites. Morphometric measurements were analyzed of 87 Phlebotomus caucasicus and 156 Phlebotomus mongolensis. Univariate and multivariate analysis were carried out to determine significant morphometric variables for discrimination of the two species. Finally, seven morphological characteristics of 65 female Phlebotomus caucasicus and 124 female Phlebotomus mongolensis were described.Results: Univariate and multivariate analyses of 10 morphometric variables via Discriminant Function Analysis(DFA) and Principal Component Analysis(PCA) showed that five morphometric variables had an accuracy of 100% for discriminating female Phlebotomus caucasicus and Phlebotomus mongolensis. Moreover, PCA revealed that the five morphometric variables with the highest loadings separated these two species. Morphological studies on antennal flagellum(and its associated structures) and mouth-parts of female specimens demonstrated significant differences in several structures.Conclusions: The results show that morphological and morphometrical features can be used to discriminate two female isomorphic species, Phlebotomus caucasicus and Phlebotomus mongolensis accurately. 展开更多
关键词 LEISHMANIASIS PHLEBOTOMUS caucasicus PHLEBOTOMUS mongolensis Morphometry discriminant functional analysis Principal Component analysis Iran
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脑卒中患者跌倒风险的相关因素研究
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作者 段林茹 郑洁皎 +1 位作者 陈茜 李燕 《中国康复理论与实践》 CSCD 北大核心 2024年第7期811-817,共7页
目的 探索影响脑卒中患者跌倒风险的相关因素,预测跌倒风险等级。方法 回顾性分析2022年7月至2024年1月在华东医院就诊的脑卒中患者64例,记录患者就诊时的人口学资料性别、年龄、身高、体质量、卒中类型、病程,功能指标世界卫生组织残... 目的 探索影响脑卒中患者跌倒风险的相关因素,预测跌倒风险等级。方法 回顾性分析2022年7月至2024年1月在华东医院就诊的脑卒中患者64例,记录患者就诊时的人口学资料性别、年龄、身高、体质量、卒中类型、病程,功能指标世界卫生组织残疾评定量表2.0 (WHODAS 2.0)、Fugl-Meyer评定量表(FMA)、功能性前伸测试(FRT)、多方向伸展测试(MDRT)、蒙特利尔认知评估量表(MoCA),行走指标计时起立行走试验等。以脑卒中患者跌倒风险等级为因变量,先采用单因素分析,再采用判别分析对脑卒中患者跌倒风险因素进行观察。结果 纳入患者平均年龄约66岁,男性多于女性,脑梗死患者多于脑出血患者,平均病程(4.50±6.02)个月,跌倒风险等级轻度、中度、重度的脑卒中患者分别为19例、26例、19例。单因素分析显示,不同跌倒风险等级脑卒中患者间WHODAS 2.0、FMA、FMA-上肢部分(FMA-UE)、FMA-下肢部分(FMA-LE)、FRT、MDRT-向前(MDRT-F)、MDRT-向右(MDRT-R)、MoCA评分有显著性差异(F> 2.277, P <0.05)。判别分析显示,不同跌倒风险等级患者的功能参数方程不同,采用回顾法验证Fisher判别函数、Bayes判别函数正确率分别为75%、78.1%,误判率分别为25%、21.9%。结论 活动参与能力、上下肢运动功能、向前向右方向的稳定极限及认知功能影响脑卒中患者跌倒风险等级,通过功能指标建立判别函数可对跌倒风险等级进行预测。 展开更多
关键词 脑卒中 跌倒 国际功能、残疾和健康分类 世界卫生组织残疾评定量表 活动和参与 运动功能 判别分析
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Acupuncture enhances brain function in patients with mild cognitive impairment: evidence from a functional-near infrared spectroscopy study 被引量:11
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作者 M.N.Afzal Khan Usman Ghafoor +1 位作者 Ho-Ryong Yoo Keum-Shik Hong 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第8期1850-1856,共7页
Mild cognitive impairment(MCI)is a precursor to Alzheimer’s disease.It is imperative to develop a proper treatment for this neurological disease in the aging society.This observational study investigated the effects ... Mild cognitive impairment(MCI)is a precursor to Alzheimer’s disease.It is imperative to develop a proper treatment for this neurological disease in the aging society.This observational study investigated the effects of acupuncture therapy on MCI patients.Eleven healthy individuals and eleven MCI patients were recruited for this study.Oxy-and deoxy-hemoglobin signals in the prefrontal cortex during working-memory tasks were monitored using functional near-infrared spectroscopy.Before acupuncture treatment,working-memory experiments were conducted for healthy control(HC)and MCI groups(MCI-0),followed by 24 sessions of acupuncture for the MCI group.The acupuncture sessions were initially carried out for 6 weeks(two sessions per week),after which experiments were performed again on the MCI group(MCI-1).This was followed by another set of acupuncture sessions that also lasted for 6 weeks,after which the experiments were repeated on the MCI group(MCI-2).Statistical analyses of the signals and classifications based on activation maps as well as temporal features were performed.The highest classification accuracies obtained using binary connectivity maps were 85.7%HC vs.MCI-0,69.5%HC vs.MCI-1,and 61.69%HC vs.MCI-2.The classification accuracies using the temporal features mean from 5 seconds to 28 seconds and maximum(i.e,max(5:28 seconds))values were 60.6%HC vs.MCI-0,56.9%HC vs.MCI-1,and 56.4%HC vs.MCI-2.The results reveal that there was a change in the temporal characteristics of the hemodynamic response of MCI patients due to acupuncture.This was reflected by a reduction in the classification accuracy after the therapy,indicating that the patients’brain responses improved and became comparable to those of healthy subjects.A similar trend was reflected in the classification using the image feature.These results indicate that acupuncture can be used for the treatment of MCI patients. 展开更多
关键词 ACUPUNCTURE Alzheimer’s disease COGNITION convolutional neural network functional connectivity functional-near infrared spectroscopy hemodynamic response linear discriminant analysis mild cognitive impairment
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Predictive Models for Functional MRI Data
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作者 Guenadie Nibbs Peter Bajorski 《Open Journal of Statistics》 2020年第1期1-9,共9页
In this study, we analyze brain activity data describing functional magnetic resonance imaging (MRI) imaging of 820 subjects with each subject being scanned at 4 different times. This multiple scanning gives us an opp... In this study, we analyze brain activity data describing functional magnetic resonance imaging (MRI) imaging of 820 subjects with each subject being scanned at 4 different times. This multiple scanning gives us an opportunity to observe the consistency of imaging characteristics within the subjects as compared to the variability across the subjects. The most consistent characteristics are then used for the purpose of predicting subjects’ traits. We concentrate on four predictive methods (Regression, Logistic Regression, Linear Discriminant Analysis and Random Forest) in order to predict subjects’ traits such as gender and age based on the brain activities observed between brain regions. Those predictions are done based on the adjusted communication activity among the brain regions, as assessed from 4 scans of each subject. Due to a large number of such communications among the 116 brain regions, we performed a preliminary selection of the most promising pairs of brain regions. Logistic Regression performed best in classifying the subject gender based on communication activity among the brain regions. The accuracy rate was 85.6 percent for an AIC step-wise selected Logistic Regression model. On the other hand, the Logistic Regression model maintaining the entire set of ranked predictor was capable of getting an 87.7 percent accuracy rate. It is interesting to point out that the model with the AIC selected features was better classifying males, whereas the complete ranked model was better classifying females. The Random Forest technique performed best for prediction of age (grouped within five categories as provided by the original data) with 48.8 percent accuracy rate. Any set of predictors between 200 and 1600 was presenting similar rates of accuracy. 展开更多
关键词 functionAL Magnetic RESONANCE Imaging Regression LOGISTIC Regression Linear discriminANT analysis RANDOM FOREST
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小学中年级汉语阅读障碍儿童的家庭阅读兴趣特征及其判别分析
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作者 黄爽 张玉平 +1 位作者 董琼 张雅新 《贵州师范大学学报(自然科学版)》 CAS 2023年第6期118-124,共7页
为比较不同阅读能力汉语儿童的家庭阅读兴趣特征及探讨影响阅读障碍儿童形成的家庭阅读兴趣变量。从191名小学三年级儿童中筛选出阅读障碍者14名,并匹配控制组儿童14名;使用探索性因子分析探索问卷维度,方差分析比较两组儿童的差异,以... 为比较不同阅读能力汉语儿童的家庭阅读兴趣特征及探讨影响阅读障碍儿童形成的家庭阅读兴趣变量。从191名小学三年级儿童中筛选出阅读障碍者14名,并匹配控制组儿童14名;使用探索性因子分析探索问卷维度,方差分析比较两组儿童的差异,以判别分析探明影响阅读障碍儿童形成的家庭阅读兴趣变量。结果显示:探索性因子分析结果显示问卷共包括4个维度(儿童积极阅读兴趣、儿童消极阅读兴趣、父母的阅读观念及父母的阅读行为);方差分析显示阅读障碍儿童在儿童消极阅读情绪上得分显著高于控制组儿童,在其余维度上得分均低于控制组儿童;判别分析结果显示总体模型分类正确率达92.9%,儿童消极阅读兴趣是判别阅读障碍儿童和控制组儿童最高的预测变量,父母阅读行为判别力高于父母阅读观念。结论:家庭阅读兴趣是影响儿童阅读能力发展的重要因素。 展开更多
关键词 阅读障碍 家庭阅读兴趣 判别分析
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Predicting the non-breeding distributions of the two Asian subspecies of Black-tailed Godwit using morphological information
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作者 Bing-Run Zhu Mo A.Verhoeven +10 位作者 Chris J.Hassell Katherine K-S Leung Dmitry Dorofeev Qiang Ma Krairat Eiamampai Jonathan T.Coleman Uchrakhzaya Tserenbat Gankhuyag Purev-Ochir David Li Zhengwang Zhang Theunis Piersma 《Avian Research》 SCIE CSCD 2023年第1期1-6,共6页
Until recently,Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway.For this reason,all previous occurrences and counts of Black-tailed Godwits ... Until recently,Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway.For this reason,all previous occurrences and counts of Black-tailed Godwits in the flyway have been assigned to melanuroides.However,a larger-bodied subspecies,bohaii,has recently been discovered in the flyway.As a result,the occurrence of Black-tailed Godwits in the flyway needs to be reconsidered such that the specific distribution of each subspecies becomes known.To this end,we developed a simple discriminant function to assign individuals to subspecies based on their bill and wing length.Cross-validation with individuals known to be bohaii or melanuroides,based on molecular analysis,showed the developed function to be 97.7%accurate.When applied to measurements of godwits captured at 22 sites across 9 countries in East-Southeast Asia and Australia,we found that bohaii and melanuroides occurred at most sites and overlapped in their distribution from Kamchatka to Australia.We examined photos from all along the flyway to verify this surprising result,confirming that both subspecies co-occur in most locations.Based on these results,we hypothesise that bohaii and melanuroides from the west of their breeding ranges mostly migrate over Chinese mainland.Birds of both subspecies from the east of their ranges are expected to migrate along the Pacific Ocean.We encourage ringing groups in East-Southeast Asia and Australia to use this simple method to keep adding knowledge about Black-tailed Godwits in the East Asian-Australasian Flyway. 展开更多
关键词 dfa discriminant function analysis East Asian-Australasian Flyway Limosa limosa
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基于熵权-逼近理想解排序法结合体外模拟消化评价功能性水稻品质
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作者 聂晓兵 袁高阳 +4 位作者 余安安 秦心睿 金文芳 余磊 范宝磊 《食品安全质量检测学报》 CAS 北大核心 2023年第16期170-178,共9页
目的探究不同品种功能性水稻的品质差异性指标,并进行综合品质评价。方法以来源于咸宁市农业科学院的7种功能性水稻为研究对象,对其7项基本营养成分、9种矿物质元素含量、3类淀粉含量和1种血糖预测指数共计20项营养品质指标进行对比分析... 目的探究不同品种功能性水稻的品质差异性指标,并进行综合品质评价。方法以来源于咸宁市农业科学院的7种功能性水稻为研究对象,对其7项基本营养成分、9种矿物质元素含量、3类淀粉含量和1种血糖预测指数共计20项营养品质指标进行对比分析,在利用正交偏最小二乘法-判别分析(orthogonal partial least-squares discrimination analysis,OPLS-DA)筛选重要差异性指标的基础上,建立熵权-逼近理想解排序法(technique for order preference by similarity to ideal solution,TOPSIS)模型对7种功能性水稻的综合品质进行评价。结果不同品种功能性水稻的基本营养成分在较小范围内波动,但钾元素含量和淀粉含量的变化范围较大,其中水稻GN 7、GN 5、GN 6在钾元素含量方面表现较好,水稻GN 4、GN 1、GN 3抗性淀粉含量最高,预估血糖生成指数(estimated glycemic index,eGI)值更低,抗消化能力优于其他品种。OPLS-DA分析筛选出锌、钠、钾、抗性淀粉、钙、镁、灰分、支链淀粉、砷、硒、直链淀粉、镉12项指标为品质差异重要性指标,结合熵权-TOPSIS模型评价出7种功能性水稻品质的优劣顺序:GN 4、GN 1、GN 3、GN 2、GN 6、GN 5、GN 7。结论该研究建立的品质评价模型科学、合理,可广泛用于各类粮食果蔬的综合品质评价,为水稻培育、种质筛选提供理论参考。 展开更多
关键词 功能性水稻 抗性淀粉 综合品质评价 熵权-逼近理想解排序法 正交偏最小二乘法-判别分析
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电子舌对啤酒的区分识别研究 被引量:28
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作者 贾洪锋 梁爱华 +3 位作者 何江红 周凌洁 张淼 郑景洲 《食品科学》 EI CAS CSCD 北大核心 2011年第24期252-255,共4页
采用电子舌对不同品牌的啤酒及其混合样品进行识别,对所获得的数据进行主成分分析、判别因子分析和偏最小二乘回归分析。结果表明:电子舌能够有效识别不同品牌的啤酒及不同品牌啤酒的混合样品;对不同品牌啤酒的混合样品建立了偏最小二... 采用电子舌对不同品牌的啤酒及其混合样品进行识别,对所获得的数据进行主成分分析、判别因子分析和偏最小二乘回归分析。结果表明:电子舌能够有效识别不同品牌的啤酒及不同品牌啤酒的混合样品;对不同品牌啤酒的混合样品建立了偏最小二乘回归分析预测模型,电子舌响应信号和啤酒混合比例之间有很好的相关性(相关系数为0.9436),偏最小二乘回归分析模型预测误差在1.43%~3.00%之间。证明电子舌可用于啤酒的识别。 展开更多
关键词 电子舌 主成分分析 判别因子分析 偏最小二乘回归分析 啤酒
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应用电子鼻判别不同储藏条件下粳稻谷品质的研究 被引量:24
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作者 宋伟 谢同平 +1 位作者 张美玲 马宁 《中国粮油学报》 EI CAS CSCD 北大核心 2012年第5期92-96,共5页
采用法国Alpha MOS公司生产的Fox 4000型电子鼻系统对不同储藏条件下的粳稻谷品质进行检测,通过传感器响应值的主成分分析(PCA)、判别因子分析(DFA),结果表明:PCA分析能准确区分出不同储藏时间的粳稻谷样品;基于PCA分析对传感器阵列进... 采用法国Alpha MOS公司生产的Fox 4000型电子鼻系统对不同储藏条件下的粳稻谷品质进行检测,通过传感器响应值的主成分分析(PCA)、判别因子分析(DFA),结果表明:PCA分析能准确区分出不同储藏时间的粳稻谷样品;基于PCA分析对传感器阵列进行优化后重新分析,可显著提高PCA分析的识别指数;选取16个样品作为样品集建立DFA数据分析模型,并随机选取20个样品进行验证性分析,正确判别率高达93%,证明该方法可用于粳稻谷的归属判别分析;用货架寿命分析比较预测不同储藏条件下的粳稻谷品质变化,温度和水分的影响明显,30℃样品比20℃储藏的样品高出0.6~0.8个气味距离,含水量为15.5%、14.5%样品比含水量为12.5%、13.5%样品高出0.4~0.8个气味距离;结合样品霉菌数量变化,利用PLS分析法可以对粳稻谷样品的霉变程度进行预测,正确率可达到100%。 展开更多
关键词 粳稻谷 电子鼻 主成分分析法 判别因子分析法 货架寿命分析 PLS分析
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基于Fisher判别法岩溶塌陷倾向性等级分类预测 被引量:13
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作者 黄仁东 韩明 +3 位作者 张小军 张海彬 金浩 华正阳 《中国安全科学学报》 CAS CSCD 北大核心 2011年第9期70-76,共7页
为准确预测岩溶塌陷倾向性的等级分类,通过分析大量观测实例,选取岩性系数、岩体结构系数、地下水系数、覆盖层系数、地形地貌系数和环境条件系数作为模型判别因素。对12个实际观测样本进行训练,建立了基于Fisher判别分析法(FDA)的岩溶... 为准确预测岩溶塌陷倾向性的等级分类,通过分析大量观测实例,选取岩性系数、岩体结构系数、地下水系数、覆盖层系数、地形地貌系数和环境条件系数作为模型判别因素。对12个实际观测样本进行训练,建立了基于Fisher判别分析法(FDA)的岩溶塌陷倾向性等级分类预测模型。借助SPSS软件工具,得到判别模型的4个判别函数。根据判别函数对训练样本进行回判,并对2个待判样本进行预测。结果显示:第一、第二判别函数的综合判别效率达到100%,大于规定的85%,满足工程实际应用需求;对训练样本进行回判时,误判率为零,同时对待判样本的分类预测准确率为100%。 展开更多
关键词 岩溶塌陷 Fisher判别分析法(FDA) 判别函数 预测 回判
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水稻抗旱性鉴定的形态指标 被引量:83
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作者 程建峰 潘晓云 +2 位作者 刘宜柏 戴廷波 曹卫星 《生态学报》 CAS CSCD 北大核心 2005年第11期3117-3125,共9页
随着全球水资源的日益匮乏和旱灾的日趋严重,水资源短缺正成为制约我国农业发展的重要因素.培育抗旱栽培稻品种并实现水稻旱种,不但可较大程度地节约水资源,且有利于稳产增产、节约能源和减少环境污染,故栽培稻抗旱性研究作为稻作科学... 随着全球水资源的日益匮乏和旱灾的日趋严重,水资源短缺正成为制约我国农业发展的重要因素.培育抗旱栽培稻品种并实现水稻旱种,不但可较大程度地节约水资源,且有利于稳产增产、节约能源和减少环境污染,故栽培稻抗旱性研究作为稻作科学研究的重要课题显得愈来愈重要.水稻抗旱性机制较为复杂,国内外学者提出了一系列与抗旱性有关的形态、发育、生理与生化等的鉴定方法与指标,且有的已利用分子标记对一些指标进行了基因定位;但因大多数指标与产量的关系尚不甚清楚,致使有些指标在抗旱性研究中的应用价值受到质疑.本研究以旱作和淹水试验为处理,采用模糊隶属函数分析,以穗颈节粗为指标进行水稻抗旱性的单因子间接评定和以穗颈节粗、单本株有效穗、实粒数/穗、谷粒宽或结实率为指标进行水稻抗旱性的综合间接评定.以认同的采用产量抗旱系数(旱作下产量与淹水下产量之比)为鉴定指标的直接评定为依据,对上述两种间接评定的结果进行判别分析,从而验证试验中被采用指标和方法的准确性和可靠性.结果表明,以旱作穗颈节粗为指标的水稻抗旱性单一间接评定与以产量抗旱系数为指标的水稻抗旱性直接评定的吻合度为88.2%~100.0%,达极显著水平,即穗颈节粗可作为水稻抗旱性鉴定与评价的单一间接评定指标;且吻合度随品种类型而变,其中以籼型杂交稻的评定为最高(100.0%),其次是常规籼稻(91.7%),常规粳稻稍低(88.2%).以旱作多个抗旱性状为指标的综合间接评定与以产量抗旱系数为指标的水稻抗旱性直接评定的吻合度均达100%,即穗颈节粗、单本株有效穗、实粒数/穗、谷粒宽和结实率可作为水稻抗旱性鉴定与评价的综合间接评定指标,且与品种类型无关.因此,旱作条件下,以穗颈节粗为指标的水稻抗旱性单一间接评定和以穗颈节粗、单本株有效穗、实粒数/穗、谷粒宽和结实率为指标的综合间接评定均是非常客观、简便易行、准确可靠和易被育种者接受的评定指标和方法,可应用于生产实践. 展开更多
关键词 水稻 形态指标 抗旱性鉴定 穗颈节粗 模糊隶属函数分析 判别分析
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稳定湖相沉积物和风成黄土粒度判别函数的建立及其意义 被引量:37
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作者 张平 宋春晖 +7 位作者 杨用彪 高红山 张红艳 刘维明 潘美慧 刘平 胡思虎 夏维民 《沉积学报》 CAS CSCD 北大核心 2008年第3期501-507,共7页
沉积物粒度变化主要受搬运介质、搬运方式、沉积环境和气候等多种因素的控制,通过粒度分析可判别沉积物的成因类型,推断其形成的沉积环境,解释环境演变。利用统计学方法对典型稳定湖相沉积物(罗布泊湖相样品282块,岱海湖相样品123块)和... 沉积物粒度变化主要受搬运介质、搬运方式、沉积环境和气候等多种因素的控制,通过粒度分析可判别沉积物的成因类型,推断其形成的沉积环境,解释环境演变。利用统计学方法对典型稳定湖相沉积物(罗布泊湖相样品282块,岱海湖相样品123块)和典型风成黄土(甘肃兰州榆中样品263块)粒度参数进行定量化分析,并经稳定湖相和风成沉积物验证,获得稳定湖相与风成沉积物的判别公式:F(湖相、风成沉积物)=20.363Mz-56.371Sd-67.922Sk+23.516Kg-55.626,若F>0,为稳定湖相沉积物,反之,F<0,则为风成沉积物。这为研究地史中稳定湖泊与风成环境沉积物的鉴别提供粒度分析定量化判别方法,它对陆相古环境、干旱化事件和尘暴事件等研究具有十分重要的借鉴价值。 展开更多
关键词 稳定湖相沉积物 风成黄土 粒度分析 判别函数
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基于功能分析的定量面向装配的设计方法研究 被引量:11
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作者 顾廷权 高国安 徐向阳 《中国机械工程》 EI CAS CSCD 北大核心 1998年第6期3-6,共4页
提出一种新的基于功能分析的定量面向装配的设计方法.并且给出分析产品可装配性的模糊评价模型和相关的实验数据.分析结果证明了方法的可靠性和有效性。
关键词 功能分析 模糊评价模型 并行设计 面向装配
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