Epitaxial high-crystallization film semiconductor heterostructures has been proved to be an effective method to prepare single-crystal films for different functional devices in modern microelectronics,electro-optics,a...Epitaxial high-crystallization film semiconductor heterostructures has been proved to be an effective method to prepare single-crystal films for different functional devices in modern microelectronics,electro-optics,and optoelectronics.With superior semiconducting properties,halide perovskite materials are rising as building blocks for heterostructures.Here,the conformal vapor phase epitaxy of CsPbBr3 on PbS single-crystal films is realized to form the CsPbBr3/PbS heterostructures via a two-step vapor deposition process.The structural characterization reveals that PbS substrates and the epilayer CsPbBr3 have clear relationships:CsPbBr3(110)//PbS(100),CsPbBr3[001]//PbS[001]and CsPbBr3[001]//PbS[010].The absorption and photoluminescence(PL)characteristics of CsPbBr3/PbS heterostructures show the broadband light absorption and efficient photogenerated carrier transfer.Photodetectors based on the heterostructures show superior photoresponsivity of 15 A/W,high detectivity of 2.65×10^(11) Jones,fast response speed of 96 ms and obvious rectification behavior.Our study offers a convenient method for establishing the high-quality CsPbBr3/PbS single-crystal film heterostructures and providing an effective way for their application in optoelectronic devices.展开更多
To predict renewable energy sources such as solar power in microgrids more accurately,a hybrid power prediction method is presented in this paper.First,the self-attention mechanism is introduced based on a bidirection...To predict renewable energy sources such as solar power in microgrids more accurately,a hybrid power prediction method is presented in this paper.First,the self-attention mechanism is introduced based on a bidirectional gated recurrent neural network(BiGRU)to explore the time-series characteristics of solar power output and consider the influence of different time nodes on the prediction results.Subsequently,an improved quantum particle swarm optimization(QPSO)algorithm is proposed to optimize the hyperparameters of the combined prediction model.The final proposed LQPSO-BiGRU-self-attention hybrid model can predict solar power more effectively.In addition,considering the coordinated utilization of various energy sources such as electricity,hydrogen,and renewable energy,a multi-objective optimization model that considers both economic and environmental costs was constructed.A two-stage adaptive multi-objective quantum particle swarm optimization algorithm aided by a Lévy flight,named MO-LQPSO,was proposed for the comprehensive optimal scheduling of a multi-energy microgrid system.This algorithm effectively balances the global and local search capabilities and enhances the solution of complex nonlinear problems.The effectiveness and superiority of the proposed scheme are verified through comparative simulations.展开更多
Objective:To reveal the distribution characteristics and demographic factors of traditional Chinese medicine(TCM)constitution among elderly individuals in China.Methods: Elderly individuals from seven regions in China...Objective:To reveal the distribution characteristics and demographic factors of traditional Chinese medicine(TCM)constitution among elderly individuals in China.Methods: Elderly individuals from seven regions in China were selected as samples in this study using a multistage cluster random sampling method.The basic information questionnaire and Constitution in Chinese Medicine Questionnaire(Elderly Edition)were used.Descriptive statistical analysis,chi-squared tests,and binary logistic regression analysis were used.Results: The single balanced constitution(BC)accounted for 23.9%.The results of the major TCM constitution types showed that BC(43.2%)accounted for the largest proportion and unbalanced constitutions ranged from 0.9%to 15.7%.East China region(odds ratio[OR]=2.097;95%confidence interval[CI],1.912 to 2.301),married status(OR=1.341;95%CI,1.235 to 1.457),and managers(OR=1.254;95%CI,1.044 to 1.505)were significantly associated with BC.Age>70 years was associated with qi-deficiency constitution and blood stasis constitution(BSC).Female sex was significantly associated with yang-deficiency constitution(OR=1.646;95%CI,1.52 to 1.782).Southwest region was significantly associated with phlegm-dampness constitution(OR=1.809;95%CI,1.569 to 2.086).North China region was significantly associated with inherited special constitution(OR=2.521;95%CI,1.569 to 4.05).South China region(OR=2.741;95%CI,1.997 to 1.3.763),Central China region(OR=8.889;95%CI,6.676 to 11.835),senior middle school education(OR=2.442;95%CI,1.932 to 3.088),and managers(OR=1.804;95%CI,1.21 to 2.69)were significantly associated with BSC.Conclusions: This study defined the distribution characteristics and demographic factors of TCM constitution in the elderly population.Adjusting and improving unbalanced constitutions,which are correlated with diseases,can help promote healthy aging through the scientific management of these demographic factors.展开更多
为提高小麦条锈病的遥感监测精度,该研究利用分数阶微分能够突出光谱的细微信息以及描述光谱数据间微小差异的优势,在对条锈病胁迫下小麦冠层光谱数据进行分数阶微分处理的基础上,构建了两波段和三波段分数阶微分光谱指数,并将其应用于...为提高小麦条锈病的遥感监测精度,该研究利用分数阶微分能够突出光谱的细微信息以及描述光谱数据间微小差异的优势,在对条锈病胁迫下小麦冠层光谱数据进行分数阶微分处理的基础上,构建了两波段和三波段分数阶微分光谱指数,并将其应用于小麦条锈病的遥感探测。研究结果表明,1.2阶次微分光谱与小麦条锈病冠层病情严重度的相关性最高,较原始反射率光谱、一阶微分光谱和二阶微分光谱分别提高了20.9%、3.9%和20.5%;基于分数阶微分光谱指数的最优分数阶次及其对应波长构建的三波段分数阶微分光谱指数对小麦条锈病的探测能力优于两波段分数阶微分光谱指数,其中分数阶微分光化学指数与冠层病情严重度的相关系数达到0.875;以分数阶微分光谱指数为自变量构建的高斯过程回归(Gaussian Process Regression,GPR)模型对小麦条锈病冠层病情严重度的预测精度优于反射率光谱指数,其训练数据集及验证数据集病情指数(Disease Index,DI)预测值和实测值间的决定系数较反射率光谱指数分别提高了3.8%和19.1%。研究结果可为进一步实现作物健康状况大面积高精度遥感监测提供参考。展开更多
为实现冬小麦条锈病早期探测、提高冬小麦产量和品质,研究了日光诱导叶绿素荧光(Solar-induced chlorophyll fluorescence,SIF)对冬小麦条锈病早期探测的可行性。基于3波段夫琅和费暗线(3-band Fraunhofer line discrimination,3FLD)和...为实现冬小麦条锈病早期探测、提高冬小麦产量和品质,研究了日光诱导叶绿素荧光(Solar-induced chlorophyll fluorescence,SIF)对冬小麦条锈病早期探测的可行性。基于3波段夫琅和费暗线(3-band Fraunhofer line discrimination,3FLD)和反射率荧光指数2种方法提取了冠层SIF数据,计算了对小麦条锈病敏感的光谱指数(Spectral index,SI),通过相关性分析优选了遥感探测小麦条锈病早期的特征参量,利用偏最小二乘(Partial least squares,PLS)算法构建冬小麦条锈病早期光谱探测模型。研究结果表明:O2-A波段的荧光强度(SIF-A)以及反射率荧光指数ρ440/ρ690、ρ675ρ690/ρ2683、ρ690/ρ655、ρ690/ρ600、DλP/D744、D705/D722均与小麦条锈病早期病情指数(Disease index,DI)达到了极显著相关,相关系数分别为-0.793、-0.523、-0.539、-0.497、0.541、0.446、0.490,可作为冬小麦条锈病早期光谱探测的荧光特征参量;基于3组SIF数据构建的PLS-SIF检验模型的决定系数分别为0.801、0.772、0.807,均方根误差分别为3.3%、3.1%、3.2%,较反射率光谱指数构建的SI-PLS模型决定系数至少提高了27%,均方根误差至少减少了24%。因此,冠层SIF数据更适于冬小麦条锈病的早期探测。本研究结果对及时进行冬小麦条锈病防控具有重要应用价值,可为利用卫星荧光遥感数据对小麦条锈病早期大面积、无损探测提供参考依据。展开更多
基金This work was supported by the Natural Science Foundation of China(Grant No.11704389)Scientific Equipment Development Project and Youth Innovation Promotion Association Project of Chinese Academy of Sciences.
文摘Epitaxial high-crystallization film semiconductor heterostructures has been proved to be an effective method to prepare single-crystal films for different functional devices in modern microelectronics,electro-optics,and optoelectronics.With superior semiconducting properties,halide perovskite materials are rising as building blocks for heterostructures.Here,the conformal vapor phase epitaxy of CsPbBr3 on PbS single-crystal films is realized to form the CsPbBr3/PbS heterostructures via a two-step vapor deposition process.The structural characterization reveals that PbS substrates and the epilayer CsPbBr3 have clear relationships:CsPbBr3(110)//PbS(100),CsPbBr3[001]//PbS[001]and CsPbBr3[001]//PbS[010].The absorption and photoluminescence(PL)characteristics of CsPbBr3/PbS heterostructures show the broadband light absorption and efficient photogenerated carrier transfer.Photodetectors based on the heterostructures show superior photoresponsivity of 15 A/W,high detectivity of 2.65×10^(11) Jones,fast response speed of 96 ms and obvious rectification behavior.Our study offers a convenient method for establishing the high-quality CsPbBr3/PbS single-crystal film heterostructures and providing an effective way for their application in optoelectronic devices.
基金supported by the National Natural Science Foundation of China under Grant 51977004the Beijing Natural Science Foundation under Grant 4212042.
文摘To predict renewable energy sources such as solar power in microgrids more accurately,a hybrid power prediction method is presented in this paper.First,the self-attention mechanism is introduced based on a bidirectional gated recurrent neural network(BiGRU)to explore the time-series characteristics of solar power output and consider the influence of different time nodes on the prediction results.Subsequently,an improved quantum particle swarm optimization(QPSO)algorithm is proposed to optimize the hyperparameters of the combined prediction model.The final proposed LQPSO-BiGRU-self-attention hybrid model can predict solar power more effectively.In addition,considering the coordinated utilization of various energy sources such as electricity,hydrogen,and renewable energy,a multi-objective optimization model that considers both economic and environmental costs was constructed.A two-stage adaptive multi-objective quantum particle swarm optimization algorithm aided by a Lévy flight,named MO-LQPSO,was proposed for the comprehensive optimal scheduling of a multi-energy microgrid system.This algorithm effectively balances the global and local search capabilities and enhances the solution of complex nonlinear problems.The effectiveness and superiority of the proposed scheme are verified through comparative simulations.
基金supported by the National Key R&D Program of China(2020YFC2003102).
文摘Objective:To reveal the distribution characteristics and demographic factors of traditional Chinese medicine(TCM)constitution among elderly individuals in China.Methods: Elderly individuals from seven regions in China were selected as samples in this study using a multistage cluster random sampling method.The basic information questionnaire and Constitution in Chinese Medicine Questionnaire(Elderly Edition)were used.Descriptive statistical analysis,chi-squared tests,and binary logistic regression analysis were used.Results: The single balanced constitution(BC)accounted for 23.9%.The results of the major TCM constitution types showed that BC(43.2%)accounted for the largest proportion and unbalanced constitutions ranged from 0.9%to 15.7%.East China region(odds ratio[OR]=2.097;95%confidence interval[CI],1.912 to 2.301),married status(OR=1.341;95%CI,1.235 to 1.457),and managers(OR=1.254;95%CI,1.044 to 1.505)were significantly associated with BC.Age>70 years was associated with qi-deficiency constitution and blood stasis constitution(BSC).Female sex was significantly associated with yang-deficiency constitution(OR=1.646;95%CI,1.52 to 1.782).Southwest region was significantly associated with phlegm-dampness constitution(OR=1.809;95%CI,1.569 to 2.086).North China region was significantly associated with inherited special constitution(OR=2.521;95%CI,1.569 to 4.05).South China region(OR=2.741;95%CI,1.997 to 1.3.763),Central China region(OR=8.889;95%CI,6.676 to 11.835),senior middle school education(OR=2.442;95%CI,1.932 to 3.088),and managers(OR=1.804;95%CI,1.21 to 2.69)were significantly associated with BSC.Conclusions: This study defined the distribution characteristics and demographic factors of TCM constitution in the elderly population.Adjusting and improving unbalanced constitutions,which are correlated with diseases,can help promote healthy aging through the scientific management of these demographic factors.
文摘为提高小麦条锈病的遥感监测精度,该研究利用分数阶微分能够突出光谱的细微信息以及描述光谱数据间微小差异的优势,在对条锈病胁迫下小麦冠层光谱数据进行分数阶微分处理的基础上,构建了两波段和三波段分数阶微分光谱指数,并将其应用于小麦条锈病的遥感探测。研究结果表明,1.2阶次微分光谱与小麦条锈病冠层病情严重度的相关性最高,较原始反射率光谱、一阶微分光谱和二阶微分光谱分别提高了20.9%、3.9%和20.5%;基于分数阶微分光谱指数的最优分数阶次及其对应波长构建的三波段分数阶微分光谱指数对小麦条锈病的探测能力优于两波段分数阶微分光谱指数,其中分数阶微分光化学指数与冠层病情严重度的相关系数达到0.875;以分数阶微分光谱指数为自变量构建的高斯过程回归(Gaussian Process Regression,GPR)模型对小麦条锈病冠层病情严重度的预测精度优于反射率光谱指数,其训练数据集及验证数据集病情指数(Disease Index,DI)预测值和实测值间的决定系数较反射率光谱指数分别提高了3.8%和19.1%。研究结果可为进一步实现作物健康状况大面积高精度遥感监测提供参考。
文摘为实现冬小麦条锈病早期探测、提高冬小麦产量和品质,研究了日光诱导叶绿素荧光(Solar-induced chlorophyll fluorescence,SIF)对冬小麦条锈病早期探测的可行性。基于3波段夫琅和费暗线(3-band Fraunhofer line discrimination,3FLD)和反射率荧光指数2种方法提取了冠层SIF数据,计算了对小麦条锈病敏感的光谱指数(Spectral index,SI),通过相关性分析优选了遥感探测小麦条锈病早期的特征参量,利用偏最小二乘(Partial least squares,PLS)算法构建冬小麦条锈病早期光谱探测模型。研究结果表明:O2-A波段的荧光强度(SIF-A)以及反射率荧光指数ρ440/ρ690、ρ675ρ690/ρ2683、ρ690/ρ655、ρ690/ρ600、DλP/D744、D705/D722均与小麦条锈病早期病情指数(Disease index,DI)达到了极显著相关,相关系数分别为-0.793、-0.523、-0.539、-0.497、0.541、0.446、0.490,可作为冬小麦条锈病早期光谱探测的荧光特征参量;基于3组SIF数据构建的PLS-SIF检验模型的决定系数分别为0.801、0.772、0.807,均方根误差分别为3.3%、3.1%、3.2%,较反射率光谱指数构建的SI-PLS模型决定系数至少提高了27%,均方根误差至少减少了24%。因此,冠层SIF数据更适于冬小麦条锈病的早期探测。本研究结果对及时进行冬小麦条锈病防控具有重要应用价值,可为利用卫星荧光遥感数据对小麦条锈病早期大面积、无损探测提供参考依据。
