This study presents a practical design strategy for a large-size Submerged Floating Tunnel(SFT)under different target environments through global-performance simulations.A coupled time-domain simulation model for SFT ...This study presents a practical design strategy for a large-size Submerged Floating Tunnel(SFT)under different target environments through global-performance simulations.A coupled time-domain simulation model for SFT is established to check hydro-elastic behaviors under the design random wave and earthquake excitations.The tunnel and mooring lines are modeled with a finite-element line model based on a series of lumped masses connected by axial,bending,and torsional springs,and thus the dynamic/structural deformability of the entire SFT is fully considered.The dummy-connection-mass method and constraint boundary conditions are employed to connect the tunnel and mooring lines in a convenient manner.Wave-and earthquake-induced hydrodynamic forces are evaluated by the Morison equation at instantaneous node positions.Several wave and earthquake conditions are selected to evaluate its global performance and sensitivity at different system parameters.Different BuoyancyWeight Ratios(BWRs),submergence depths,and tunnel lengths(and mooring intervals)are chosen to establish a design strategy for reducing the maximum mooring tension.Both static and dynamic tensions are critical to find an acceptable design depending on the given target environmental condition.BWR plays a crucial role in preventing snap loading,and the corresponding static tension is a primary factor if the environmental condition is mild.The tunnel length can significantly be extended by reducing BWR when environmental force is not that substantial.Dynamic tension becomes important in harsh environmental conditions,for which high BWR and short mooring interval are required.It is underscored that the wet natural frequencies with mooring are located away from the spectral peaks of design waves or earthquakes.展开更多
The peripheral nervous system(PNS)is a fascinatingly complex and crucial component of the human body,responsible for transmitting vital signals throughout the body's intricate network of nerves.Its efficient funct...The peripheral nervous system(PNS)is a fascinatingly complex and crucial component of the human body,responsible for transmitting vital signals throughout the body's intricate network of nerves.Its efficient functioning is paramount to our health,with any dysfunction often resulting in serious medical conditions,including motor disorders,neurological diseases,and psychiatric disorders.Recent strides in science and technology have made neuromodulation of the PNS a promising avenue for addressing these health issues.Neuromodulation involves modifying nerve activity using a range of techniques,such as electrical,chemical,optical,and mechanical stimulation.Bioelectronics plays a critical role in this effort,allowing for precise,controlled,and sustained stimulation of the PNS.This paper provides an overview of the PNS,discusses the current state of neuromodulation devices,and presents emerging trends in the field,including advances in wireless power transfer and materials,that are shaping the future of neuromodulation.展开更多
基金This work was supported by the National Research Foundation of Korea(NRF)Grant funded by the Korean Government(MSIT)(No.2017R1A5A1014883).
文摘This study presents a practical design strategy for a large-size Submerged Floating Tunnel(SFT)under different target environments through global-performance simulations.A coupled time-domain simulation model for SFT is established to check hydro-elastic behaviors under the design random wave and earthquake excitations.The tunnel and mooring lines are modeled with a finite-element line model based on a series of lumped masses connected by axial,bending,and torsional springs,and thus the dynamic/structural deformability of the entire SFT is fully considered.The dummy-connection-mass method and constraint boundary conditions are employed to connect the tunnel and mooring lines in a convenient manner.Wave-and earthquake-induced hydrodynamic forces are evaluated by the Morison equation at instantaneous node positions.Several wave and earthquake conditions are selected to evaluate its global performance and sensitivity at different system parameters.Different BuoyancyWeight Ratios(BWRs),submergence depths,and tunnel lengths(and mooring intervals)are chosen to establish a design strategy for reducing the maximum mooring tension.Both static and dynamic tensions are critical to find an acceptable design depending on the given target environmental condition.BWR plays a crucial role in preventing snap loading,and the corresponding static tension is a primary factor if the environmental condition is mild.The tunnel length can significantly be extended by reducing BWR when environmental force is not that substantial.Dynamic tension becomes important in harsh environmental conditions,for which high BWR and short mooring interval are required.It is underscored that the wet natural frequencies with mooring are located away from the spectral peaks of design waves or earthquakes.
基金Institute for Basic Science,Grant/Award Number:IBS-R026-D1Korea Medical Device Development Fund,Grant/Award Number:RMS 2022-11-1209/KMDF RS-2022-00141392+1 种基金National Research Foundation of Korea,Grant/Award Numbers:2020R1A5A1019131,2021M3D1A2049914,2022R1A5A6000846,2023R1A2C2006257Korea Evaluation Institute of Industrial Technology,Grant/Award Number:20013621。
文摘The peripheral nervous system(PNS)is a fascinatingly complex and crucial component of the human body,responsible for transmitting vital signals throughout the body's intricate network of nerves.Its efficient functioning is paramount to our health,with any dysfunction often resulting in serious medical conditions,including motor disorders,neurological diseases,and psychiatric disorders.Recent strides in science and technology have made neuromodulation of the PNS a promising avenue for addressing these health issues.Neuromodulation involves modifying nerve activity using a range of techniques,such as electrical,chemical,optical,and mechanical stimulation.Bioelectronics plays a critical role in this effort,allowing for precise,controlled,and sustained stimulation of the PNS.This paper provides an overview of the PNS,discusses the current state of neuromodulation devices,and presents emerging trends in the field,including advances in wireless power transfer and materials,that are shaping the future of neuromodulation.
