A double sampling circuit to eliminating fixed pattern noise(FPN) in CMOS image sensor (CIS) is presented. Double sampling is implemented by column switch capacitor amplifier directly, and offset compensation is added...A double sampling circuit to eliminating fixed pattern noise(FPN) in CMOS image sensor (CIS) is presented. Double sampling is implemented by column switch capacitor amplifier directly, and offset compensation is added to the amplifier to suppress column FPN. The amplifier is embedded in a 64×64 CIS and successfully fabricated with chartered 0.35 μm process. Theory analysis and circuit simulation indicate that FPN can be suppressed from millivolt to microvolt. Test results show that FPN is smaller than one least-significant bit of 8 bit ADC. FPN is reduced to an acceptable level with double sampling technique implemented with switch capacitor amplifier.展开更多
Understanding and controlling phase separation in nonequilibrium colloidal systems are of both fundamental and applied importance.In this article,we investigate the spatiotemporal control of phase separation in chemic...Understanding and controlling phase separation in nonequilibrium colloidal systems are of both fundamental and applied importance.In this article,we investigate the spatiotemporal control of phase separation in chemically active immotile colloids.We show that a population of silver colloids can spontaneously phase separate into dense clusters in hydrogen peroxide(H_(2)O_(2))due to phoretic attraction.The characteristic length of the formed pattern was quantified and monitored over time,revealing a growth and coarsening phase with different growth kinetics.By tuning the trigger frequency of light,the lengths and growth kinetics of the clusters formed by silver colloids in H_(2)O_(2)can be controlled.In addition,structured light was used to precisely control the shape,size,and contour of the phase-separated patterns.This study provides insight into the microscopic details of the phase separation of chemically active colloids induced by phoretic attraction,and presents a generic strategy for controlling the spatiotemporal evolution of the resulting mesoscopic patterns.展开更多
At least 13 active fault zones have developed in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,and there have been undergone 17 MS≥7.0 earthquakes,the largest earthquake is 1950 Chayu MS 8.5 ea...At least 13 active fault zones have developed in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,and there have been undergone 17 MS≥7.0 earthquakes,the largest earthquake is 1950 Chayu MS 8.5 earthquake,which has very strong seismic activity.Therefore,carrying out engineering construction in the Sichuan-Tibet transport corridor is a huge challenge for geological technological personnel.To determining the spatial geometric distribution,activity of active faults and geological safety risk in the Sichuan-Tibet transport corridor.Based on remote sensing images,ground surveys,and chronological tests,as well as the deep geophysical and current GPS data,we investigated the geometry,segmentation,and paleoearthquake history of five major active fault zones in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,namely the Xianshuihe,Litang,Batang,Jiali-Chayu and Lulang-Yigong.The five major fault zones are all Holocene active faults,which contain strike-slip components as well as thrust or normal fault components,and contain multiple branch faults.The Selaha-Kangding segment of the Xianshuihe fault zone,the Maoyaba and Litang segment of the Litang fault zone,the middle segment(Yigong-Tongmai-Bomi)of Jiali-Chayu fault zone and Lulang-Yigong fault zone have the risk of experiencing strong earthquakes in the future,with a high possibility of the occurrence of MS≥7.0 earthquakes.The Jinsha River and the Palong-Zangbu River,which is a high-risk area for geological hazard chain risk in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor.Construction and safe operation Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,need strengthen analysis the current crustal deformation,stress distribution and fault activity patterns,clarify active faults relationship with large earthquakes,and determine the potential maximum magnitude,epicenters,and risk range.This study provides basic data for understanding the activity,seismicity,and tectonic deformation patterns of the regional fa展开更多
文摘采用野外定点调查的方法,研究了红火蚁Solenopsis invicta多蚁后型种群婚飞新形成蚁巢的局域空间分布规律.结果表明,短期内婚飞形成的活动蚁巢在局域平面空间上呈均匀分布,分布的基本成分为单个蚁巢,且蚁巢间相互排斥.在平面空间上不同间隔距离间该类型蚁巢半方差值呈明显规律性变化,具有空间相关性.建立了5个球状模型,其变程分别为12.6、14.1、9.7、13.3和14.5 m,平均为12.8 m.
基金Supported by National Natural Science Foundation of China (No.60576025).
文摘A double sampling circuit to eliminating fixed pattern noise(FPN) in CMOS image sensor (CIS) is presented. Double sampling is implemented by column switch capacitor amplifier directly, and offset compensation is added to the amplifier to suppress column FPN. The amplifier is embedded in a 64×64 CIS and successfully fabricated with chartered 0.35 μm process. Theory analysis and circuit simulation indicate that FPN can be suppressed from millivolt to microvolt. Test results show that FPN is smaller than one least-significant bit of 8 bit ADC. FPN is reduced to an acceptable level with double sampling technique implemented with switch capacitor amplifier.
基金supported by the Shenzhen Science and Technology Program(RCYX20210609103122038 and JCYJ20210324121408022)the National Natural Science Foundation of China(T2322006,T2325027,12274448,12225410 and 12074243)
文摘Understanding and controlling phase separation in nonequilibrium colloidal systems are of both fundamental and applied importance.In this article,we investigate the spatiotemporal control of phase separation in chemically active immotile colloids.We show that a population of silver colloids can spontaneously phase separate into dense clusters in hydrogen peroxide(H_(2)O_(2))due to phoretic attraction.The characteristic length of the formed pattern was quantified and monitored over time,revealing a growth and coarsening phase with different growth kinetics.By tuning the trigger frequency of light,the lengths and growth kinetics of the clusters formed by silver colloids in H_(2)O_(2)can be controlled.In addition,structured light was used to precisely control the shape,size,and contour of the phase-separated patterns.This study provides insight into the microscopic details of the phase separation of chemically active colloids induced by phoretic attraction,and presents a generic strategy for controlling the spatiotemporal evolution of the resulting mesoscopic patterns.
基金supported by the National Natural Science Foundation of China(42177184)the Balance Research Funds of the Chinese Academy of Geological Sciences(60)the China Geological Survey(DD20221816)。
文摘At least 13 active fault zones have developed in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,and there have been undergone 17 MS≥7.0 earthquakes,the largest earthquake is 1950 Chayu MS 8.5 earthquake,which has very strong seismic activity.Therefore,carrying out engineering construction in the Sichuan-Tibet transport corridor is a huge challenge for geological technological personnel.To determining the spatial geometric distribution,activity of active faults and geological safety risk in the Sichuan-Tibet transport corridor.Based on remote sensing images,ground surveys,and chronological tests,as well as the deep geophysical and current GPS data,we investigated the geometry,segmentation,and paleoearthquake history of five major active fault zones in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,namely the Xianshuihe,Litang,Batang,Jiali-Chayu and Lulang-Yigong.The five major fault zones are all Holocene active faults,which contain strike-slip components as well as thrust or normal fault components,and contain multiple branch faults.The Selaha-Kangding segment of the Xianshuihe fault zone,the Maoyaba and Litang segment of the Litang fault zone,the middle segment(Yigong-Tongmai-Bomi)of Jiali-Chayu fault zone and Lulang-Yigong fault zone have the risk of experiencing strong earthquakes in the future,with a high possibility of the occurrence of MS≥7.0 earthquakes.The Jinsha River and the Palong-Zangbu River,which is a high-risk area for geological hazard chain risk in the Ya'an-Linzhi section of the Sichuan-Tibet transport corridor.Construction and safe operation Ya'an-Linzhi section of the Sichuan-Tibet transport corridor,need strengthen analysis the current crustal deformation,stress distribution and fault activity patterns,clarify active faults relationship with large earthquakes,and determine the potential maximum magnitude,epicenters,and risk range.This study provides basic data for understanding the activity,seismicity,and tectonic deformation patterns of the regional fa