During the course of calculating the rice evapotranspiration using weather factors,we often find that some independent variables have multiple correlation.The phenomena can lead to the traditional multivariate regress...During the course of calculating the rice evapotranspiration using weather factors,we often find that some independent variables have multiple correlation.The phenomena can lead to the traditional multivariate regression model which based on least square method distortion.And the stability of the model will be lost.The model will be built based on partial least square regression in the paper,through applying the idea of main component analyze and typical correlation analyze,the writer picks up some component from original material.Thus,the writer builds up the model of rice evapotranspiration to solve the multiple correlation among the independent variables (some weather factors).At last,the writer analyses the model in some parts,and gains the satisfied result.展开更多
偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)是一种线性分类方法,不能充分表达数据之间的非线性关系,难以适应非线性数据的分类识别。针对该问题,结合softmax回归能够表达非线性特征,提出融合softmax回归...偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)是一种线性分类方法,不能充分表达数据之间的非线性关系,难以适应非线性数据的分类识别。针对该问题,结合softmax回归能够表达非线性特征,提出融合softmax回归的偏最小二乘判别分析算法(PLS-S-DA)。为了验证PLS-S-DA对非线性数据的有效性,以准确率、运行时间、查准率、查全率和F1-score为评价指标,采用四组UCI数据集和中药寒热药性数据集测试PLS-S-DA的性能,并与PLS-DA等五种分类算法对比。结果表明,对具有非线性特征的数据,PLS-S-DA相比于其他算法有更高的准确率,并对寒药和热药有更强的识别能力。展开更多
Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laborat...Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laboratories under a controlled environment.There is an increasing need to measure fiber maturity using low-cost(in general less than $20000)and small portable systems.In this study,a laboratory feasibility was performed to assess the ability of the shortwave infrared hyperspectral imaging(SWIR HSI)technique for determining the conditioned fiber maturity,and as a comparison,a bench-top commercial and expensive(in general greater than $60000)near infrared(NIR)instrument was used.Results Although SWIR HSI and NIR represent different measurement technologies,consistent spectral characteristics were observed between the two instruments when they were used to measure the maturity of the locule fiber samples in seed cotton and of the well-defined fiber samples,respectively.Partial least squares(PLS)models were established using different spectral preprocessing parameters to predict fiber maturity.The high prediction precision was observed by a lower root mean square error of prediction(RMSEP)(<0.046),higher R_(p)^(2)(>0.518),and greater percentage(97.0%)of samples within the 95% agreement range in the entire NIR region(1000-2500 nm)without the moisture band at 1940 nm.Conclusion SWIR HSI has a good potential for assessing cotton fiber maturity in a laboratory environment.展开更多
文摘During the course of calculating the rice evapotranspiration using weather factors,we often find that some independent variables have multiple correlation.The phenomena can lead to the traditional multivariate regression model which based on least square method distortion.And the stability of the model will be lost.The model will be built based on partial least square regression in the paper,through applying the idea of main component analyze and typical correlation analyze,the writer picks up some component from original material.Thus,the writer builds up the model of rice evapotranspiration to solve the multiple correlation among the independent variables (some weather factors).At last,the writer analyses the model in some parts,and gains the satisfied result.
文摘偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)是一种线性分类方法,不能充分表达数据之间的非线性关系,难以适应非线性数据的分类识别。针对该问题,结合softmax回归能够表达非线性特征,提出融合softmax回归的偏最小二乘判别分析算法(PLS-S-DA)。为了验证PLS-S-DA对非线性数据的有效性,以准确率、运行时间、查准率、查全率和F1-score为评价指标,采用四组UCI数据集和中药寒热药性数据集测试PLS-S-DA的性能,并与PLS-DA等五种分类算法对比。结果表明,对具有非线性特征的数据,PLS-S-DA相比于其他算法有更高的准确率,并对寒药和热药有更强的识别能力。
基金supported partially by the USDA-ARS Research Project#6054-44000-080-00D.
文摘Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laboratories under a controlled environment.There is an increasing need to measure fiber maturity using low-cost(in general less than $20000)and small portable systems.In this study,a laboratory feasibility was performed to assess the ability of the shortwave infrared hyperspectral imaging(SWIR HSI)technique for determining the conditioned fiber maturity,and as a comparison,a bench-top commercial and expensive(in general greater than $60000)near infrared(NIR)instrument was used.Results Although SWIR HSI and NIR represent different measurement technologies,consistent spectral characteristics were observed between the two instruments when they were used to measure the maturity of the locule fiber samples in seed cotton and of the well-defined fiber samples,respectively.Partial least squares(PLS)models were established using different spectral preprocessing parameters to predict fiber maturity.The high prediction precision was observed by a lower root mean square error of prediction(RMSEP)(<0.046),higher R_(p)^(2)(>0.518),and greater percentage(97.0%)of samples within the 95% agreement range in the entire NIR region(1000-2500 nm)without the moisture band at 1940 nm.Conclusion SWIR HSI has a good potential for assessing cotton fiber maturity in a laboratory environment.