This study proposes two metrics using the nearest neighbors method to improve the accuracy of time-series forecasting. These two metrics can be treated as a hybrid forecasting approach to combine linear and non-linear...This study proposes two metrics using the nearest neighbors method to improve the accuracy of time-series forecasting. These two metrics can be treated as a hybrid forecasting approach to combine linear and non-linear forecasting techniques. One metric redefines the distance in k-nearest neighbors based on the coefficients of autoregression (AR) in time series. Meanwhile, an improvement to Kulesh's adaptive metrics in the nearest neighbors is also presented. To evaluate the performance of the two proposed metrics, three types of time-series data, namely deterministic synthetic data, chaotic time-series data and real time-series data, are predicted. Experimental results show the superiority of the proposed AR-enhanced k-nearest neighbors methods to the traditional k-nearest neighbors metric and Kulesh's adaptive metrics.展开更多
In this paper, an improved weighted least squares （WLS）, together with autoregressive （AR） model, is proposed to improve prediction accuracy of earth rotation parameters（ERP）. Four weighting schemes are develope...In this paper, an improved weighted least squares （WLS）, together with autoregressive （AR） model, is proposed to improve prediction accuracy of earth rotation parameters（ERP）. Four weighting schemes are developed and the optimal power e for determination of the weight elements is studied. The results show that the improved WLS-AR model can improve the ERP prediction accuracy effectively, and for different prediction intervals of ERP, different weight scheme should be chosen.展开更多
目的:通过整合数据库信息,筛选并明确藤梨根在肿瘤转移各主要途径中起关键作用的蛋白与分子通路,进而比较分析其在各类转移途径中的作用差异,以确定藤梨根主要干预的核心转移途径,从而为后续深入开展藤梨根抗肿瘤转移研究提供理论基础...目的:通过整合数据库信息,筛选并明确藤梨根在肿瘤转移各主要途径中起关键作用的蛋白与分子通路,进而比较分析其在各类转移途径中的作用差异,以确定藤梨根主要干预的核心转移途径,从而为后续深入开展藤梨根抗肿瘤转移研究提供理论基础并指明具体方向。方法:通过中药数据分析平台(TCMSP)筛选藤梨根的活性成分及对应靶点,再通过Gene Cards,OMIM和Uniprot三个数据库分别整合淋巴转移和骨转移的相关靶点,将靶点数据导入jvenn做出韦恩图,对韦恩图进行分析,评价两类癌转移途径,优选途径导入String平台得到蛋白质-蛋白质相互作用(protein-protein interaction,PPI),导入Metascape中进行基因本体论(gene ontology,GO)功能富集分析和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)通路富集分析,根据KEGG富集得到的通路绘制相关气泡图。整理国内外对藤梨根及其在癌症作用过程中的有效成分、蛋白等在实验中的发现,结合数据库对内容分析整理。整理总结国内关于藤梨根及其复方在临床使用过程中的数据,结合蛋白及分子通路研究为藤梨根及其复方在临床使用提供基础性研究。结果:藤梨根在干预肿瘤转移时,对不同转移途径的效能存在差异。具体而言,其在抑制骨转移方面的效果显著优于淋巴转移。针对淋巴转移途径,藤梨根并非首选治疗药物;相反,在骨转移途径中,藤梨根表现出突出的干预潜力。机制探究显示,这一作用主要与其调控相关转录过程有关。结论:藤梨根对多种癌症的骨转移都是有效的,不仅限于乳腺癌的骨转移。展开更多
基金the National Natural Science Foundation of China(No.61203337)the Natural Science Foundation of Shanghai(No.12ZR1440200)
文摘This study proposes two metrics using the nearest neighbors method to improve the accuracy of time-series forecasting. These two metrics can be treated as a hybrid forecasting approach to combine linear and non-linear forecasting techniques. One metric redefines the distance in k-nearest neighbors based on the coefficients of autoregression (AR) in time series. Meanwhile, an improvement to Kulesh's adaptive metrics in the nearest neighbors is also presented. To evaluate the performance of the two proposed metrics, three types of time-series data, namely deterministic synthetic data, chaotic time-series data and real time-series data, are predicted. Experimental results show the superiority of the proposed AR-enhanced k-nearest neighbors methods to the traditional k-nearest neighbors metric and Kulesh's adaptive metrics.
基金supported by the Foundation for the Author of National Excellent Doctoral Dissertation of China (2007B51)Natural Science Foundation of China (41174008)
文摘In this paper, an improved weighted least squares （WLS）, together with autoregressive （AR） model, is proposed to improve prediction accuracy of earth rotation parameters（ERP）. Four weighting schemes are developed and the optimal power e for determination of the weight elements is studied. The results show that the improved WLS-AR model can improve the ERP prediction accuracy effectively, and for different prediction intervals of ERP, different weight scheme should be chosen.
文摘目的:通过整合数据库信息,筛选并明确藤梨根在肿瘤转移各主要途径中起关键作用的蛋白与分子通路,进而比较分析其在各类转移途径中的作用差异,以确定藤梨根主要干预的核心转移途径,从而为后续深入开展藤梨根抗肿瘤转移研究提供理论基础并指明具体方向。方法:通过中药数据分析平台(TCMSP)筛选藤梨根的活性成分及对应靶点,再通过Gene Cards,OMIM和Uniprot三个数据库分别整合淋巴转移和骨转移的相关靶点,将靶点数据导入jvenn做出韦恩图,对韦恩图进行分析,评价两类癌转移途径,优选途径导入String平台得到蛋白质-蛋白质相互作用(protein-protein interaction,PPI),导入Metascape中进行基因本体论(gene ontology,GO)功能富集分析和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)通路富集分析,根据KEGG富集得到的通路绘制相关气泡图。整理国内外对藤梨根及其在癌症作用过程中的有效成分、蛋白等在实验中的发现,结合数据库对内容分析整理。整理总结国内关于藤梨根及其复方在临床使用过程中的数据,结合蛋白及分子通路研究为藤梨根及其复方在临床使用提供基础性研究。结果:藤梨根在干预肿瘤转移时,对不同转移途径的效能存在差异。具体而言,其在抑制骨转移方面的效果显著优于淋巴转移。针对淋巴转移途径,藤梨根并非首选治疗药物;相反,在骨转移途径中,藤梨根表现出突出的干预潜力。机制探究显示,这一作用主要与其调控相关转录过程有关。结论:藤梨根对多种癌症的骨转移都是有效的,不仅限于乳腺癌的骨转移。
