Jimin Lee

Dr. Jimin Lee

Georgia Institute of Technology, Atlanta, Georgia, USA
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2020 in Sensors and Actuators B: Chemical
Verified
Journal Article
Closed access
KPKee-Ryung Park
Kee-Ryung Park
HCHong-Baek Cho
Hong-Baek Cho
Jimin LeeJimin Lee
Jimin Lee
YSYoseb Song
Yoseb Song
WKWoo-Byoung Kim
Woo-Byoung Kim
YCYong-Ho Choa
Yong-Ho Choa

10 February 2024 in npj Flexible Electronics
Verified
Journal Article
Open access
PDF file
JLJinwoo Lee
Jinwoo Lee
KKKangkyu Kwon
Kangkyu Kwon
ISIra Soltis
Ira Soltis
JMJared Matthews
Jared Matthews
Yoon Jae LeeYoon Jae Lee
Yoon Jae Lee
Woon-Hong YeoWoon-Hong Yeo
Woon-Hong Yeo
The age and stroke-associated decline in musculoskeletal strength degrades the ability to perform daily human tasks using the upper extremities. Here, we introduce an intelligent upper-limb exoskeleton system that utilizes deep learning to predict human intention for strength augmentation. The embedded soft wearable sensors provide sensory feedback by collecting real-time muscle activities, which are simultaneously computed to determine the user’s intended movement. Cloud-based deep learning predicts four upper-limb joint motions with an average accuracy of 96.2% at a 500–550 ms response rate, suggesting that the exoskeleton operates just by human intention. In addition, an array of soft pneumatics assists the intended movements by providing 897 newtons of force while generating a displacement of 87 mm at maximum. The intent-driven exoskeleton can reduce human muscle activities by 3.7 times on average compared to the unassisted exoskeleton.

28 September 2020 in Scientific Reports
Verified
Journal Article
Open access
PDF file
Jimin LeeJimin Lee
Jimin Lee
ELEun Jae Lee
Eun Jae Lee
THTae-Yeon Hwang
Tae-Yeon Hwang
JKJongryoul Kim
Jongryoul Kim
YCYong-Ho Choa
Yong-Ho Choa
Recent studies on next-generation permanent magnets have focused on filling in the gap between rare-earth magnets and rare-earth-free magnets, taking into account both the cost-effectiveness and magnetic performance of the magnetic materials. As an improved rare-earth-free magnet candidate, here, Ca-substituted M-type Sr-lean hexaferrite particles within a nano- to micro-scale regime, produced using an ultrasonic spray pyrolysis method, are investigated. Theoretically, the maximum coercivity (Hc) can be achieved in submicron Sr-ferrite crystals (i.e., 0.89 μm). The plate-like resultants showed a significant enhancement in Hc, up to a record high of 7880.4 Oe, with no deterioration in magnetization (M: 71–72 emu/g). This resulted in more favorable magnetic properties than those of the traditional Sr–La–Co ferrites. On the basis of microstructural analysis and fitting results based on the law of approach to saturation method, the Ca-substitution effects on the change in size and anisotropic characteristics of the ferrite particles, including pronounced lateral crystal growth and a strong increase in magnetocrystalline anisotropy, are clearly demonstrated. The cost-effective, submicron, and Ca-substituted Sr-ferrite is an excellent potential magnet and moreover may overcome the limitations of traditional hard magnetic materials.

9 July 2024 in ACS Applied Materials & Interfaces
Verified
Journal Article
Open access
MSMaria Sattar
Maria Sattar
Yoon Jae LeeYoon Jae Lee
Yoon Jae Lee
HKHyeonseok Kim
Hyeonseok Kim
MAMichael Adams
Michael Adams
MGMatthew Guess
Matthew Guess
Woon-Hong YeoWoon-Hong Yeo
Woon-Hong Yeo
Continuous monitoring of physiological signals from the human body is critical in health monitoring, disease diagnosis, and therapeutics. Despite the needs, the existing wearable medical devices rely on either bulky wired systems or battery-powered devices needing frequent recharging. Here, we introduce a wearable, self-powered, thermoelectric flexible system architecture for wireless portable monitoring of physiological signals without recharging batteries. This system harvests an exceptionally high open circuit voltage of 175-180 mV from the human body, powering the wireless wearable bioelectronics to detect electrophysiological signals on the skin continuously. The thermoelectric system shows long-term stability in performance for 7 days with stable power management. Integrating screen printing, laser micromachining, and soft packaging technologies enables a multilayered, soft, wearable device to be mounted on any body part. The demonstration of the self-sustainable wearable system for detecting electromyograms and electrocardiograms captures the potential of the platform technology to offer various opportunities for continuous monitoring of biosignals, remote health monitoring, and automated disease diagnosis.

31 January 2025 in ACS Nano
Verified
Journal Article
Open access
TKTae Woog Kang
Tae Woog Kang
Yoon Jae LeeYoon Jae Lee
Yoon Jae Lee
BRBruno Rigo
Bruno Rigo
ISIra Soltis
Ira Soltis
Jimin LeeJimin Lee
Jimin Lee
Woon-Hong YeoWoon-Hong Yeo
Woon-Hong Yeo
Sensory rehabilitation in pediatric patients with traumatic spinal cord injury is challenging due to the ongoing development of their nervous systems. However, these sensory problems often result in nonuse of the impaired limb, which disturbs impaired limb rehabilitation and leads to overuse of the contralateral limb and other physical or psychological issues that may persist. Here, we introduce a soft nanomembrane sensor-enabled wearable glove system that wirelessly delivers a haptic sensation from the hand with tactile feedback responses for sensory impairment assistance. The smart glove system uses gold nanomembranes, copper-elastomer composites, and laser-induced graphene for the sensitive detection of pressure, temperature, and strain changes. The nanomaterial sensors are integrated with low-profile tactile actuators and wireless flexible electronics to offer real-time sensory feedback. The wearable system's thin-film sensors demonstrate 98% and 97% accuracy in detecting pressure and finger flexion, respectively, along with a detection coverage of real-life temperature changes as an effective rehabilitation tool. Collectively, the upper-limb sensory impairment assistance system embodies the latest in soft materials and wearable technology to incorporate soft sensors and miniaturized actuators and maximize its compatibility with human users, offering a promising solution for patient sensory rehabilitation.

16 February 2024 in Science Advances
Verified
Journal Article
Open access
Jimin LeeJimin Lee
Jimin Lee
HKHojoong Kim
Hojoong Kim
HLHyo-Ryoung Lim
Hyo-Ryoung Lim
Yun Soung KimYun Soung Kim
Yun Soung Kim
TTThai Thanh Hoang Thi
Thai Thanh Hoang Thi
Woon-Hong YeoWoon-Hong Yeo
Woon-Hong Yeo
Achieving large-scale, cost-effective, and reproducible manufacturing of stem cells with the existing devices is challenging. Traditional single-use cell-bag bioreactors, limited by their rigid and single-point sensors, struggle with accuracy and scalability for high-quality cell manufacturing. Here, we introduce a smart bioreactor system that enables multi-spatial sensing for real-time, wireless culture monitoring. This scalable system includes a low-profile, label-free thin-film sensor array and electronics integrated with a flexible cell bag, allowing for simultaneous assessment of culture properties such as pH, dissolved oxygen, glucose, and temperature, to receive real-time feedback for up to 30 days. The experimental results show the accurate monitoring of time-dynamic and spatial variations of stem cells and myoblast cells with adjustable carriers from a plastic dish to a 2-liter cell bag. These advances open up the broad applicability of the smart sensing system for large-scale, lower-cost, reproducible, and high-quality engineered cell manufacturing for broad clinical use.