Publications by authors named "Jeongdae Ha"
System-level wearable electronics require to be flexible to ensure conformal contact with the skin, but they also need to integrate rigid and bulky functional components to achieve system-level functionality. As one of integration methods, folding integration offers simplified processing and enhanced functionality through rigid-soft region separation, but so far, it has mainly been applied to modality of electrical sensing and stimulation. This paper introduces a vialess heterogeneous skin patch with multi modalities that separates the soft region and strain-robust region through folded structure.
View Article and Find Full Text PDFStructures such as 3D buckling have been widely used to impart stretchability to devices. However, these structures have limitations when applied to piezoelectric devices due to the uneven distribution of internal strain during deformation. When strains with opposite directions simultaneously affect piezoelectric materials, the electric output can decrease due to cancellation.
View Article and Find Full Text PDFA stealthy neural recorder for the study of behaviour in primates.
Nat Biomed Eng
June 2025
Article Synopsis
- Researchers have developed a stealthy neural recorder designed to monitor brain signals in non-human primates, allowing for the study of their natural behaviors.
- The device features a fully implantable, wireless, battery-free module that records brain activity and movement, along with a flexible 32-electrode neural probe.
- Successfully tested on a freely moving monkey, the recorder gathered data for over a month, which was then used to train an AI model to classify the animal's eating behaviors.
Various strain isolation strategies that combine rigid and stretchable regions for stretchable electronics were recently proposed, but the vulnerability of inorganic materials to mechanical stress has emerged as a major impediment to their performance. We report a strain-isolation system that combines heteropolymers with different elastic moduli (i.e.
View Article and Find Full Text PDFTaste Bud-Inspired Single-Drop Multitaste Sensing for Comprehensive Flavor Analysis with Deep Learning Algorithms.
ACS Appl Mater Interfaces
October 2023
Article Synopsis
- - The electronic tongue (E-tongue) system attempts to mimic human taste perception but struggles with complex taste interactions and maintaining accurate results in variable conditions.
- - A new artificial E-tongue system has been developed, using multiple taste sensors and a deep-learning algorithm to identify four tastes (saltiness, sourness, astringency, sweetness) and obtain taste profiles for different wines.
- - The E-tongue system has achieved high accuracy in distinguishing between wines (about 95%) and effectively proposed a recommendation system, which improves user experience while addressing some taste assessment discrepancies.
Article Synopsis
- Transfer printing is a method to combine different materials by transferring functional components from one surface to another for use in electronic devices.
- Traditional wet transfer printing faces issues like unwanted movements and distortions because of fluid dynamics and slow chemical reactions.
- This study introduces a dry transfer printing technique that uses thermal expansion differences for better efficiency and reliability, showing promise for a wide range of applications beyond what's possible with older methods.