Publications by authors named "H B Choi"

Non-destructive color sensors are widely applied for rapid analysis of various biological and healthcare point-of-care applications. However, existing red, green, blue (RGB)-based color sensor systems, relying on the conversion to human-perceptible color spaces like hue, saturation, lightness (HSL), hue, saturation, value (HSV), as well as cyan, magenta, yellow, key (CMYK) and the CIE L*a*b* (CIELAB) exhibit limitations compared to spectroscopic methods. The integration of machine learning (ML) techniques presents an opportunity to enhance data analysis and interpretation, enabling insights discovery, prediction, process automation, and decision-making.

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Colloidal quantum dots (QDs) are solution-processable semiconductor nanocrystals with favorable optoelectronic characteristics, one of which is their multi-excitonic behavior that enables broadband polychromatic light generation and amplification from monodisperse QDs. However, the practicality of this has been limited by the difficulty in achieving spatial separation and patterning of different colors as well as the high pumping intensity required to excite the multi-excitonic states. Here, we have addressed these issues by integrating monodisperse QDs in multi-excitonic states into a specially designed cavity, in which the QDs exhibit an anisotropic polychromatic emission (APE) characteristic that allows for tuning the emission from green to red by shifting the observation direction from perpendicular to lateral.

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Mechanoluminescence platforms, combining phosphors with elastic polymer matrix, have emerged in smart wearable technology due to their superior elasticity and mechanically driven luminescent properties. However, their luminescence performance often deteriorates under extreme elastic conditions owing to a misinterpretation of polymer matrix behavior. Here, we unveil the role of the polymer matrices in mechanoluminescence through an interface-triboelectric effect driven by elasticity, achieving both high elasticity and brightness.

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Alzheimer's disease (AD) is a devastating neurodegenerative condition characterized by progressive cognitive decline with currently no effective treatment available. One of the most critical areas in AD research is the identification of reliable biomarkers, which are essential for accurate diagnosis, prognostic assessment, and the development of targeted therapies. In this study, we introduce two novel reactive EEG (rEEG) biomarkers aimed at enhancing the diagnosis of AD and mild cognitive impairment (MCI).

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Stable H-O and radiogenic Sr isotopic compositions of bottled water in South Korea were investigated to trace water origins and to elucidate hydrogeochemical water-rock interactions within aquifers. Eighty-one bottled water samples were collected across the country. The δD and δO values, and Sr/Sr ratios and Sr contents of groundwater-sourced bottled water samples were in the ranges of -68 to -40 ‰, -10 to -7 ‰, 0.

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