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Dynamics of a Stochastic Epidemic Model with Age-group
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作者 LAN Xiaomin CHEN Guangmin +5 位作者 ZHOU Ruiyang ZHENG Kuicheng CAI Shaojian WEI Fengying JIN Zhen MAO Xuerong 《应用数学》 北大核心 2025年第1期294-307,共14页
A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t... A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases. 展开更多
关键词 Epidemic model Age groups PERSISTENCE EXTINCTION
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A Sparse Optimal Scoring Model with Adherent Penalty
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作者 Hou Dandan Liu Yongjin 《数学理论与应用》 2024年第4期100-115,共16页
We consider the task of binary classification in the high-dimensional setting where the number of features of the given data is larger than the number of observations.To accomplish this task,we propose an adherently p... We consider the task of binary classification in the high-dimensional setting where the number of features of the given data is larger than the number of observations.To accomplish this task,we propose an adherently penalized optimal scoring(APOS)model for simultaneously performing discriminant analysis and feature selection.In this paper,an efficient algorithm based on the block coordinate descent(BCD)method and the SSNAL algorithm is developed to solve the APOS approximately.The convergence results of our method are also established.Numerical experiments conducted on simulated and real datasets demonstrate that the proposed model is more efficient than several sparse discriminant analysis methods. 展开更多
关键词 Sparse discriminant analysis Optimal scoring Feature selection BCD method SSNAL algorithm
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改良式冰袋在踝关节骨折患者中的早期应用
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作者 钟美玉 邱宇彤 《福建医药杂志》 CAS 2023年第2期144-146,共3页
踝关节骨折后肢体的肿胀疼痛是骨科最常见的临床症状之一,踝关节周围软组织比较薄弱,骨折肿胀消退需要1~2周,这将决定手术的选择时机.骨折处在血液和水肿液共同作用下可能形成纤维瘢痕,肌肉、肌腱和关节囊等软组织发生纤维化,可造成肢... 踝关节骨折后肢体的肿胀疼痛是骨科最常见的临床症状之一,踝关节周围软组织比较薄弱,骨折肿胀消退需要1~2周,这将决定手术的选择时机.骨折处在血液和水肿液共同作用下可能形成纤维瘢痕,肌肉、肌腱和关节囊等软组织发生纤维化,可造成肢体活动功能受限,长时间的肿胀可能造成骨折患者残疾,进而影响患者的生活质量.尽早消除患肢肿胀能缩短手术时间,提高解剖复位效果[1]. 展开更多
关键词 踝关节骨折 关节囊 患肢肿胀 水肿液 早期应用 纤维瘢痕 临床症状 纤维化
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