针对现有的波达方向(direction of arrival,DOA)估计方法在低信噪比、小快拍、多信源条件下估计精度较低的问题,提出一种基于并行坐标下降算法的DOA估计方法.首先,对空域等角度均匀划分,构造超完备冗余字典;其次,采用并行坐标下降算法...针对现有的波达方向(direction of arrival,DOA)估计方法在低信噪比、小快拍、多信源条件下估计精度较低的问题,提出一种基于并行坐标下降算法的DOA估计方法.首先,对空域等角度均匀划分,构造超完备冗余字典;其次,采用并行坐标下降算法的思想对稀疏信号进行重构,得到信号在空域的稀疏系数矩阵;最后,将稀疏矩阵行向量的l2-范数映射到空域网格上,得到准确的DOA估计值.仿真实验结果表明:在低信噪比、小快拍、多信源条件下,该方法优于子空间类算法、贪婪类算法以及凸优化类算法,具有更低的均方根误差(RMSE)、更高的DOA估计精度和运行效率.展开更多
Objective:Practice related to the traditional postpartum confinement custom“Zuo Yuezi”vary among individuals,and its relationship with postpartum depression(PPD)remains unclear.This study aims to explore the current...Objective:Practice related to the traditional postpartum confinement custom“Zuo Yuezi”vary among individuals,and its relationship with postpartum depression(PPD)remains unclear.This study aims to explore the current practice and heterogeneity of“Zuo Yuezi”among Chinese women and to analyze its association with PPD.Methods:A cross-sectional study was conducted among 542 women from 3 hospitals between January and February 2016.Data were collected on whether participants practiced“Zuo Yuezi”,their willingness and attitudes toward“Zuo Yuezi”,demographic characteristics,adherence to specific“Zuo Yuezi”practices,emotional experiences during the“Zuo Yuezi”period,and PPD symptoms.Latent profile analysis(LPA)was used to identify heterogeneity in“Zuo Yuezi”practices,and multivariate logistic regression was used to analyze the association between practice patterns and PPD.Results:A total of 542 postpartum women completed the survey.About 98%(531/542)of participants reported practicing“Zuo Yuezi”,among whom 41.2%followed traditional customs and 29.5%followed parental advice.Approximately 95%of women practiced“Zuo Yuezi”for≥30 days,and nearly half strictly followed a 30-day“Zuo Yuezi”period.Significant heterogeneity was observed in practice components and adherence levels,with the greatest heterogeneity in dietary practices and the lowest in hygiene practices.Latent profile analysis identified 4 levels of adherence to“Zuo Yuezi”practices:low,mediumlow,medium,and high.Higher adherence was associated with belief in disease prevention,home-based“Zuo Yuezi”practices,and longer“Zuo Yuezi”duration.Lower adherence was associated with an increased risk of PPD(χ^(2)=16.103,P<0.05).Conclusion:The practice of“Zuo Yuezi”is widespread but heterogeneous.Lower adherence to“Zuo Yuezi”practices may increase the risk of postpartum depression,highlighting the need for culturally sensitive and individualized perinatal care.展开更多
文摘针对现有的波达方向(direction of arrival,DOA)估计方法在低信噪比、小快拍、多信源条件下估计精度较低的问题,提出一种基于并行坐标下降算法的DOA估计方法.首先,对空域等角度均匀划分,构造超完备冗余字典;其次,采用并行坐标下降算法的思想对稀疏信号进行重构,得到信号在空域的稀疏系数矩阵;最后,将稀疏矩阵行向量的l2-范数映射到空域网格上,得到准确的DOA估计值.仿真实验结果表明:在低信噪比、小快拍、多信源条件下,该方法优于子空间类算法、贪婪类算法以及凸优化类算法,具有更低的均方根误差(RMSE)、更高的DOA估计精度和运行效率.
基金supported by the National Natural Science Foundation(82273643 and 81973059)the Hunan Provincial Natural Science Foundation(2023JJ30712)+1 种基金the Youth Science Foundation of Hunan Provincial Natural Science Foundation Committee Class A Project(2025JJ20095)the Nutrition and Care of Maternal&Child Research Fund Project of Biostime Institute of Nutrition&Care(2018BINCMCF31),China.
文摘Objective:Practice related to the traditional postpartum confinement custom“Zuo Yuezi”vary among individuals,and its relationship with postpartum depression(PPD)remains unclear.This study aims to explore the current practice and heterogeneity of“Zuo Yuezi”among Chinese women and to analyze its association with PPD.Methods:A cross-sectional study was conducted among 542 women from 3 hospitals between January and February 2016.Data were collected on whether participants practiced“Zuo Yuezi”,their willingness and attitudes toward“Zuo Yuezi”,demographic characteristics,adherence to specific“Zuo Yuezi”practices,emotional experiences during the“Zuo Yuezi”period,and PPD symptoms.Latent profile analysis(LPA)was used to identify heterogeneity in“Zuo Yuezi”practices,and multivariate logistic regression was used to analyze the association between practice patterns and PPD.Results:A total of 542 postpartum women completed the survey.About 98%(531/542)of participants reported practicing“Zuo Yuezi”,among whom 41.2%followed traditional customs and 29.5%followed parental advice.Approximately 95%of women practiced“Zuo Yuezi”for≥30 days,and nearly half strictly followed a 30-day“Zuo Yuezi”period.Significant heterogeneity was observed in practice components and adherence levels,with the greatest heterogeneity in dietary practices and the lowest in hygiene practices.Latent profile analysis identified 4 levels of adherence to“Zuo Yuezi”practices:low,mediumlow,medium,and high.Higher adherence was associated with belief in disease prevention,home-based“Zuo Yuezi”practices,and longer“Zuo Yuezi”duration.Lower adherence was associated with an increased risk of PPD(χ^(2)=16.103,P<0.05).Conclusion:The practice of“Zuo Yuezi”is widespread but heterogeneous.Lower adherence to“Zuo Yuezi”practices may increase the risk of postpartum depression,highlighting the need for culturally sensitive and individualized perinatal care.
