Publications by authors named "K S Pyun"

Radiative thermal management technologies that utilize thermal radiation from nano/microstructure for cooling and heating have gained significant attention in sustainable energy research. Passive radiative cooling and solar heating operate continuously, which may lead to additional heating or cooling energy consumption due to undesired cooling or heating during cold nighttime/winters or hot daytime/summers. To overcome the limitation, recent studies have focused on developing radiative thermal management technologies that can toggle radiative cooling on and off or possess switchable dual cooling and heating modes to realize sustainable and efficient thermal management.

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Liquid crystal elastomers hold promise in various fields due to their reversible transition of mechanical and optical properties across distinct phases. However, the lack of local phase patterning techniques and irreversible phase programming has hindered their broad implementation. Here we introduce laser-induced dynamic crosslinking, which leverages the precision and control offered by laser technology to achieve high-resolution multilevel patterning and transmittance modulation.

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Soft electromechanical sensors have led to a new paradigm of electronic devices for novel motion-based wearable applications in our daily lives. However, the vast amount of random and unidentified signals generated by complex body motions has hindered the precise recognition and practical application of this technology. Recent advancements in artificial-intelligence technology have enabled significant strides in extracting features from massive and intricate data sets, thereby presenting a breakthrough in utilizing wearable sensors for practical applications.

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Article Synopsis
  • Radiative thermoregulation is an energy-efficient thermal management technique, and this study explores a new polydimethylsiloxane (PDMS) micro-nanofiber matrix that enables both cooling and heating.
  • The electrospun PDMS fibers reflect 93% of solar energy while allowing for effective infrared emission, achieving a daytime cooling effect of about 3.8°C.
  • The material's ability to change its structural properties under mechanical stress allows for adjustable solar reflectivity, supporting flexible thermoregulation that could help combat climate change and energy shortages.
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Recent advancements in wearable electronics offer seamless integration with the human body for extracting various biophysical and biochemical information for real-time health monitoring, clinical diagnostics, and augmented reality. Enormous efforts have been dedicated to imparting stretchability/flexibility and softness to electronic devices through materials science and structural modifications that enable stable and comfortable integration of these devices with the curvilinear and soft human body. However, the optical properties of these devices are still in the early stages of consideration.

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