Dear Editor,Infectionw ithsevereacuterespirator ysy ndrome coronavirus2(SARS-CoV-2),whichcausescoronavirus disease 2019 (COVID-19),is initiated by the virus spike (S)glycoprotein binding to its cellular receptor such ...Dear Editor,Infectionw ithsevereacuterespirator ysy ndrome coronavirus2(SARS-CoV-2),whichcausescoronavirus disease 2019 (COVID-19),is initiated by the virus spike (S)glycoprotein binding to its cellular receptor such as angiotensin converting enzyme 2 (ACE2)[1,2].Subsequently,the virus may take two routes for its entry into the host cells,including an endocytic route that ends up in endosomal compartment,and a plasma membrane route on the cell surface.In both routes,fusion between the viral and plasma membrane was required to introduce the viral genome into the cytoplasm[3].Similarly,SARS-CoV-2 infection results in the expression of fusogenic S glycoprotein on the host cell membrane.展开更多
多频管中电流法(Pipeline Current Mapper,PCM)是管线无损检测的常用方法之一。为了满足地下金属管线探测的需求,该文在研究PCM测量金属管线的基础上,确定了“工”字型摆放的线圈接收结构,明确了信号接收系统的总体方案,开发了一款可在...多频管中电流法(Pipeline Current Mapper,PCM)是管线无损检测的常用方法之一。为了满足地下金属管线探测的需求,该文在研究PCM测量金属管线的基础上,确定了“工”字型摆放的线圈接收结构,明确了信号接收系统的总体方案,开发了一款可在强噪声环境下应用的地下金属管线信号接收系统。采用STM32F103RCT6作为系统的主控芯片,对预放大电路、信号调理电路、程控放大电路、A/D采集电路及人机交互界面进行设计。采用卡尔曼滤波对信号进行最优估计,通过管道定位、探伤算法,对地下金属管线的位置及管线的腐蚀程度进行判断。最终经过实验测试,该系统可以有效检测出管线的位置并检测管线腐蚀点,其误差在5%以内。展开更多
Stringent attitude determination accuracy is required for the development of the advanced space technologies and thus the accuracy improvement of digital sun sensors is necessary.In this paper,we presented a proposal ...Stringent attitude determination accuracy is required for the development of the advanced space technologies and thus the accuracy improvement of digital sun sensors is necessary.In this paper,we presented a proposal for measurement error analysis of a digital sun sensor.A system modeling including three different error sources was built and employed for system error analysis.Numerical simulations were also conducted to study the measurement error introduced by different sources of error.Based on our model and study,the system errors from different error sources are coupled and the system calibration should be elaborately designed to realize a digital sun sensor with extra-high accuracy.展开更多
基金supported by the National Key Research&Development Program of China (2018YFA0900804, 2019YFA0903801)the National Natural Science Foundation of China (31970685)。
文摘Dear Editor,Infectionw ithsevereacuterespirator ysy ndrome coronavirus2(SARS-CoV-2),whichcausescoronavirus disease 2019 (COVID-19),is initiated by the virus spike (S)glycoprotein binding to its cellular receptor such as angiotensin converting enzyme 2 (ACE2)[1,2].Subsequently,the virus may take two routes for its entry into the host cells,including an endocytic route that ends up in endosomal compartment,and a plasma membrane route on the cell surface.In both routes,fusion between the viral and plasma membrane was required to introduce the viral genome into the cytoplasm[3].Similarly,SARS-CoV-2 infection results in the expression of fusogenic S glycoprotein on the host cell membrane.
文摘多频管中电流法(Pipeline Current Mapper,PCM)是管线无损检测的常用方法之一。为了满足地下金属管线探测的需求,该文在研究PCM测量金属管线的基础上,确定了“工”字型摆放的线圈接收结构,明确了信号接收系统的总体方案,开发了一款可在强噪声环境下应用的地下金属管线信号接收系统。采用STM32F103RCT6作为系统的主控芯片,对预放大电路、信号调理电路、程控放大电路、A/D采集电路及人机交互界面进行设计。采用卡尔曼滤波对信号进行最优估计,通过管道定位、探伤算法,对地下金属管线的位置及管线的腐蚀程度进行判断。最终经过实验测试,该系统可以有效检测出管线的位置并检测管线腐蚀点,其误差在5%以内。
基金the financial support by the National 863 Project ( No. 2012AA121503 )the China NSF projects ( No. 61377012 , No. 61505094 )China Postdoctoral Science Foundation funded project ( 2015M571034 )
文摘Stringent attitude determination accuracy is required for the development of the advanced space technologies and thus the accuracy improvement of digital sun sensors is necessary.In this paper,we presented a proposal for measurement error analysis of a digital sun sensor.A system modeling including three different error sources was built and employed for system error analysis.Numerical simulations were also conducted to study the measurement error introduced by different sources of error.Based on our model and study,the system errors from different error sources are coupled and the system calibration should be elaborately designed to realize a digital sun sensor with extra-high accuracy.
