Pressure ulcers remain a persistent challenge in healthcare,particularly for individuals with limited mobility or compromised sensation.Early detection is critical to prevent ischemic damage leading to necrosis,infect...Pressure ulcers remain a persistent challenge in healthcare,particularly for individuals with limited mobility or compromised sensation.Early detection is critical to prevent ischemic damage leading to necrosis,infections,and prolonged hospital stays.Conventional sensing technologies that integrate into the mattress,while effective in gathering data on pressure distributions,are restricted to stationary environments,and they can miss significant periods when patients leave their beds or shift positions.Furthermore,these systems do not offer consistent information on the specific spatial distribution of pressure across the body,because the sensors integrate with the mattress and not the body.Recent research establishes capabilities in soft,skin-interfaced wireless alternatives,but in designs that require specialized processes and materials that might not scale effectively for practical production and use.Here,we present a wireless,skin-integrated pressure monitoring system that mounts on the skin,in anatomically matched forms and with soft mechanical interfaces,for continuous data collection.This platform,built on manufacturable components and designs,features an array of soft,elastomer-encapsulated pressure sensors that minimize discomfort,with wireless communications and an independent power management system to enable operation across diverse healthcare settings,including homes,outpatient facilities,and operating rooms,all without physical tethers.Additionally,an external alarm satellite device delivers vibratory and visual alerts if predefined pressure thresholds are exceeded,guiding caregivers or patients to take timely action.Experimental and finite element analysis support the design principles,and deployments on patients in hospital settings illustrate modes for practical use.展开更多
This study presents dual-mode memory transistor that accommodates memory and synaptic operations utilizing photoinduced charge trapping at the interface between poly(1,4-butanediol diacrylate)(pBDDA)and Parylene diele...This study presents dual-mode memory transistor that accommodates memory and synaptic operations utilizing photoinduced charge trapping at the interface between poly(1,4-butanediol diacrylate)(pBDDA)and Parylene dielectric layer.Memory characteristics were implemented based on the photoresponsivity of dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene(DNTT),enabling instantaneous electron storage under combined optical and electrical inputs,with retention times up to 10,000 s.Meanwhile,synaptic characteristics were induced by gradual charge trapping via optical pulse stimulation.Synaptic plasticity was confirmed via the potentiation-depression curve,emulating key features of biological nervous system,namely short-term memory(STM)and long-term memory(LTM).Furthermore,the fingerprint recognition tasks highlighted identification and authentication abilities by incorporating our synaptic function into an artificial neural network(ANN).The dual-mode memory transistor,fabricated on a business card,showed excellent compatibility with flexible optoelectronics,maintaining stable memory and synaptic performance over 500 bending cycles with minimal changes in memory window,memory ratio,and potentiation-depression behavior.展开更多
Various core memory devices have been proposed for utilization in future inmemory computing technology featuring high energy efficiency.Flash memory is considered as a viable choice owing to its high integration densi...Various core memory devices have been proposed for utilization in future inmemory computing technology featuring high energy efficiency.Flash memory is considered as a viable choice owing to its high integration density,stability,and reliability,which has been verified by commercialized products.However,its high operating voltage and slow operation speed issues caused by the tunneling mechanism make its adoption in in-memory computing applications difficult.In this paper,we introduce a dual-mode memory device named“ferro-floating memory”,fabricated using van der Waals(vdW)materials(h-BN,MoS2,andα-In2Se3).The vdW material,α-In2Se3,acts as a polarization control layer for the ferroelectric memory operation and charge storage layer for the conventional flash memory operation.Compared to the tunnelingbased memory operation,the ferro-floating memory operates 1.9 and 3.3 times faster at 6.7 and 5.8 times lower operating voltages for programming and erasing operations,respectively.The dual-mode operation improves the linearity of conductance change by 5 times and the dynamic range by 48%through achieving conductance variation regions.Furthermore,we assess the effects of the variation in device operating voltage on neural networks and suggest a memory array operating scheme for maximizing the networks'performance through various training/inference simulations.展开更多
Variations in parameters associated with the ambient environment can introduce noise in soft,body-worn sensors.For example,many piezoresistive pressure sensors exhibit a high degree of sensitivity to fluctuations in t...Variations in parameters associated with the ambient environment can introduce noise in soft,body-worn sensors.For example,many piezoresistive pressure sensors exhibit a high degree of sensitivity to fluctuations in temperature,thereby requiring active compensation strategies.The research presented here addresses this challenge with a multilayered 3D microsystem design that integrates four piezoresistive sensors in a full-Wheatstone bridge configuration.An optimized layout of the sensors relative to the neutral mechanical plane leads to both an insensitivity to temperature and an increased sensitivity to pressure,relative to previously reported devices that rely on similar operating principles.Integrating this 3D pressure sensor into a soft,flexible electronics platform yields a system capable of real-time,wireless measurements from the surface of the skin.Placement above the radial and carotid arteries yields high-quality waveforms associated with pulsatile blood flow,with quantitative correlations to blood pressure.The results establish the materials and engineering aspects of a technology with broad potential in remote health monitoring.展开更多
基金supported by the Querrey Simpson Institute for Bioelectronics at Northwestern University.S.Y.acknowledges support from the National Research Foundation of Korea(NRF)grant(No.RS-2025-23525124)funded by the Korea government(MSIT)+4 种基金the BK21 FOUR program(Digital Anti-aging Convergence Research Group,Inje University)support from the National NaturalScience Foundation of China(12202241)support from the National Research Foundation of Korea(NRF)grant(Nos.RS-2022-NR072054 and RS-2020-NR049568)the Institute of Information&Communications Technology Planning&Evaluation(IITP)under the Graduate School of Artificial Intelligence Semiconductor(IITP-2025-RS-2023-00256472)grantfunded by the Korea government(MSIT),and the BK21 FOUR program(Connected AI Education&Research Program for Industry and Society Innovation,KAIST EE,No.4120200113769).
文摘Pressure ulcers remain a persistent challenge in healthcare,particularly for individuals with limited mobility or compromised sensation.Early detection is critical to prevent ischemic damage leading to necrosis,infections,and prolonged hospital stays.Conventional sensing technologies that integrate into the mattress,while effective in gathering data on pressure distributions,are restricted to stationary environments,and they can miss significant periods when patients leave their beds or shift positions.Furthermore,these systems do not offer consistent information on the specific spatial distribution of pressure across the body,because the sensors integrate with the mattress and not the body.Recent research establishes capabilities in soft,skin-interfaced wireless alternatives,but in designs that require specialized processes and materials that might not scale effectively for practical production and use.Here,we present a wireless,skin-integrated pressure monitoring system that mounts on the skin,in anatomically matched forms and with soft mechanical interfaces,for continuous data collection.This platform,built on manufacturable components and designs,features an array of soft,elastomer-encapsulated pressure sensors that minimize discomfort,with wireless communications and an independent power management system to enable operation across diverse healthcare settings,including homes,outpatient facilities,and operating rooms,all without physical tethers.Additionally,an external alarm satellite device delivers vibratory and visual alerts if predefined pressure thresholds are exceeded,guiding caregivers or patients to take timely action.Experimental and finite element analysis support the design principles,and deployments on patients in hospital settings illustrate modes for practical use.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean Government(MSIT)(RS-2023-00210194,RS-2024-00438999,RS-2024-00442020,RS-2024-00454508)supported by Institute of Information&communications Technology Planning&Evaluation(IITP)under the artificial intelligence semiconductor support program to nurture the best talents(IITP-(2025)-RS-2023-00253914)grant funded by the Korea government(MSIT)and the research fund of Hanyang University(HY-2024-2696).
文摘This study presents dual-mode memory transistor that accommodates memory and synaptic operations utilizing photoinduced charge trapping at the interface between poly(1,4-butanediol diacrylate)(pBDDA)and Parylene dielectric layer.Memory characteristics were implemented based on the photoresponsivity of dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene(DNTT),enabling instantaneous electron storage under combined optical and electrical inputs,with retention times up to 10,000 s.Meanwhile,synaptic characteristics were induced by gradual charge trapping via optical pulse stimulation.Synaptic plasticity was confirmed via the potentiation-depression curve,emulating key features of biological nervous system,namely short-term memory(STM)and long-term memory(LTM).Furthermore,the fingerprint recognition tasks highlighted identification and authentication abilities by incorporating our synaptic function into an artificial neural network(ANN).The dual-mode memory transistor,fabricated on a business card,showed excellent compatibility with flexible optoelectronics,maintaining stable memory and synaptic performance over 500 bending cycles with minimal changes in memory window,memory ratio,and potentiation-depression behavior.
基金National Research Foundation of Korea,Grant/Award Numbers:2020M3F3A2A02082436,2020R1A4A2002806,2021R1A2C2010026,2022M3F3A2A01072215Samsung Electronics Co.Ltd.,Grant/Award Number:IO201210-07994-01。
文摘Various core memory devices have been proposed for utilization in future inmemory computing technology featuring high energy efficiency.Flash memory is considered as a viable choice owing to its high integration density,stability,and reliability,which has been verified by commercialized products.However,its high operating voltage and slow operation speed issues caused by the tunneling mechanism make its adoption in in-memory computing applications difficult.In this paper,we introduce a dual-mode memory device named“ferro-floating memory”,fabricated using van der Waals(vdW)materials(h-BN,MoS2,andα-In2Se3).The vdW material,α-In2Se3,acts as a polarization control layer for the ferroelectric memory operation and charge storage layer for the conventional flash memory operation.Compared to the tunnelingbased memory operation,the ferro-floating memory operates 1.9 and 3.3 times faster at 6.7 and 5.8 times lower operating voltages for programming and erasing operations,respectively.The dual-mode operation improves the linearity of conductance change by 5 times and the dynamic range by 48%through achieving conductance variation regions.Furthermore,we assess the effects of the variation in device operating voltage on neural networks and suggest a memory array operating scheme for maximizing the networks'performance through various training/inference simulations.
基金supported by a grant from Kyung Hee University in 2022(KHU-20220916)。
文摘Variations in parameters associated with the ambient environment can introduce noise in soft,body-worn sensors.For example,many piezoresistive pressure sensors exhibit a high degree of sensitivity to fluctuations in temperature,thereby requiring active compensation strategies.The research presented here addresses this challenge with a multilayered 3D microsystem design that integrates four piezoresistive sensors in a full-Wheatstone bridge configuration.An optimized layout of the sensors relative to the neutral mechanical plane leads to both an insensitivity to temperature and an increased sensitivity to pressure,relative to previously reported devices that rely on similar operating principles.Integrating this 3D pressure sensor into a soft,flexible electronics platform yields a system capable of real-time,wireless measurements from the surface of the skin.Placement above the radial and carotid arteries yields high-quality waveforms associated with pulsatile blood flow,with quantitative correlations to blood pressure.The results establish the materials and engineering aspects of a technology with broad potential in remote health monitoring.
