During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil d...During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is located.The monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction areas.The former is the gathering point of the entire urban population.There are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation cover.Several existing items requiremonitoring.However,monitoring distance is long,and providing early warning is difficult.This study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence deformation.Then,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway operation.Results show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 mm.And FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation.展开更多
This research focuses on the seismic responses of the historic masonry minarets,conducted through the creation of a digital twin model using finite element methods.The study initiated the development of a comprehensiv...This research focuses on the seismic responses of the historic masonry minarets,conducted through the creation of a digital twin model using finite element methods.The study initiated the development of a comprehensive model in the ANSYS Workbench,supplemented by operational modal analysis(OMA),to ascertain the dynamic characteristics of the minaret.The alignment of numerical and experimental frequency data was achieved using the response surface method(RSM)within ANSYS Workbench DesignXplorer.This process resulted in the establishment of a digital twin,accurately representing the physical minaret in a virtual environment.Blender^(■)software was then used to simulate the effects of two consecutive earthquakes in Türkiye that occurred on February 6,2023.The simulations highlighted the heightened susceptibility of the minaret,especially in its upper sections,to consecutive seismic activities,culminating in significant damage and collapse.This innovative approach,merging traditional engineering methods with a cutting-edge digital simulation,provides a profound insight into the seismic behavior of historical structures.The research underscores the importance of advanced seismic modeling for the effective preservation and resilience of architectural heritage sites against earthquake risks.展开更多
Metal-oxide-semiconductor field effect transistor(MOSFET) intrinsic gain degradation caused by channel length modulation(CLM) effect is examined.A simplified model based on Berkeley short-channel insulator-gate field ...Metal-oxide-semiconductor field effect transistor(MOSFET) intrinsic gain degradation caused by channel length modulation(CLM) effect is examined.A simplified model based on Berkeley short-channel insulator-gate field effect transistor model version 4(BSIM4) current expression for sub-100 nm MOSFET intrinsic gain is deduced,which only needs a few technology parameters.With this transistor intrinsic gain model,complementary metal-oxide-semiconductor(CMOS) operational amplifier(op amp) DC gain could be predicted.A two-stage folded cascode op amp is used as an example in this work.Non-minimum length device is used to improve the op amp DC gain.An improvement of 20 dB is proved when using doubled channel length design.Optimizing transistor bias condition and using advanced technology with thinner gate dielectric thickness and shallower source/drain junction depth can also increase the op amp DC gain.After these,a full op amp DC gain scaling roadmap is proposed,from 130 nm technology node to 32 nm technology node.Five scaled op amps are built and their DC gains in simulation roll down from 69.6 to 41.1 dB.Simulation shows transistors biased at higher source-drain voltage will have more impact on the op amp DC gain scaling over technology.The prediction based on our simplified gain model agrees with SPICE simulation results.展开更多
基金financial supports for this research project by the National Natural Science Foundation of China(Nos.41602308,41967037)supported by Zhejiang Provincial Natural Science Foundation of China under Grant No.LY20E080005+1 种基金funded by National Key Research and Development Projects of China(No.2019YFC507502)Guangxi Science and Technology Plan Project(No.RZ2100000161).
文摘During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is located.The monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction areas.The former is the gathering point of the entire urban population.There are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation cover.Several existing items requiremonitoring.However,monitoring distance is long,and providing early warning is difficult.This study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence deformation.Then,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway operation.Results show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 mm.And FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation.
基金product of the research project titled,Video Camera Based Structural Health Monitoring of Historic Masonry Minarets and Development of a Long-Term Decision-Making Model Based on Deep Learning Method(Project No.222M140)supported by TÜBİTAK 1001-Scientific and the Technological Research Projects Support Program.
文摘This research focuses on the seismic responses of the historic masonry minarets,conducted through the creation of a digital twin model using finite element methods.The study initiated the development of a comprehensive model in the ANSYS Workbench,supplemented by operational modal analysis(OMA),to ascertain the dynamic characteristics of the minaret.The alignment of numerical and experimental frequency data was achieved using the response surface method(RSM)within ANSYS Workbench DesignXplorer.This process resulted in the establishment of a digital twin,accurately representing the physical minaret in a virtual environment.Blender^(■)software was then used to simulate the effects of two consecutive earthquakes in Türkiye that occurred on February 6,2023.The simulations highlighted the heightened susceptibility of the minaret,especially in its upper sections,to consecutive seismic activities,culminating in significant damage and collapse.This innovative approach,merging traditional engineering methods with a cutting-edge digital simulation,provides a profound insight into the seismic behavior of historical structures.The research underscores the importance of advanced seismic modeling for the effective preservation and resilience of architectural heritage sites against earthquake risks.
文摘Metal-oxide-semiconductor field effect transistor(MOSFET) intrinsic gain degradation caused by channel length modulation(CLM) effect is examined.A simplified model based on Berkeley short-channel insulator-gate field effect transistor model version 4(BSIM4) current expression for sub-100 nm MOSFET intrinsic gain is deduced,which only needs a few technology parameters.With this transistor intrinsic gain model,complementary metal-oxide-semiconductor(CMOS) operational amplifier(op amp) DC gain could be predicted.A two-stage folded cascode op amp is used as an example in this work.Non-minimum length device is used to improve the op amp DC gain.An improvement of 20 dB is proved when using doubled channel length design.Optimizing transistor bias condition and using advanced technology with thinner gate dielectric thickness and shallower source/drain junction depth can also increase the op amp DC gain.After these,a full op amp DC gain scaling roadmap is proposed,from 130 nm technology node to 32 nm technology node.Five scaled op amps are built and their DC gains in simulation roll down from 69.6 to 41.1 dB.Simulation shows transistors biased at higher source-drain voltage will have more impact on the op amp DC gain scaling over technology.The prediction based on our simplified gain model agrees with SPICE simulation results.
