김용성 교수

We report transmissive color filters based on subwavelength dielectric gratings that can replace conventional dye-based color filters used in backside-illuminated CMOS image sensor (BSI CIS) technologies. The filters are patterned in an 80 nm-thick poly silicon film on a 115 nm-thick SiO₂ spacer layer. They are optimized for operating at the primary RGB colors, exhibit peak transmittance of 60-80%, and have an almost insensitive response over a ± 20° angular range. This technology ena

BACKGROUND AND PURPOSE: Previous studies have reported that early hospital arrival improves clinical outcomes in patients with acute ischemic stroke; however, whether early arrival is associated with favorable outcomes regardless of reperfusion therapy and the type of stroke onset time is unclear. Thus, we investigated the impact of onset-to-door time on outcomes and evaluated the predictors of pre-hospital delay after ischemic stroke. METHODS: Consecutive acute ischemic stroke patients who arri

This paper presents a uniform micro/nano double-roughened superhydrophobic surface with a high static contact angle (CA) and low contact angle hysteresis (CAH). The proposed micro/nano complex structured surfaces were self-fabricated simply and efficiently using a very simple and low-cost nonlithographic sequential process, which consists of aluminum (Al) sputtering, anodization of the Al layer and pore widening, without specific equipment and additional subsequent processes. The wetting propert

Currently, Internet of medical things-based technologies provide a foundation for remote data collection and medical assistance for various diseases. Along with developments in computer vision, the application of Artificial Intelligence and Deep Learning in IOMT devices aids in the design of effective CAD systems for various diseases such as melanoma cancer even in the absence of experts. However, accurate segmentation of melanoma skin lesions from images by CAD systems is necessary to carry out

BACKGROUND: Elevated metabolic activity of amygdala is known to be related to atherosclerotic cardiovascular event by increasing inflammatory cell production from bone marrow. We tried to identify the factors of metabolic activity in the amygdala, vertebrae, liver, spleen, and internal carotid artery related to the future vascular events after stroke. METHODS: F-fluorodeoxyglucose (FDG) positron emission tomography between August 1, 2015 and February 28, 2020. We compared the FDG uptake in the a

BACKGROUND: Spontaneous disease stabilization of desmoid-type fibromatosis (DF) has been demonstrated in many reports, and the watchful waiting approach without any frontline treatment is becoming popular as an initial management strategy. In this study, we aimed to assess the disease stabilization rate and identify predictive factors for disease stabilization of DF in patients with conservative treatment. METHODS: We reviewed 76 patients with sporadic extra-abdominal DF who were managed with fr

Abstract Controlling defect states in a buffer layer for organic photo devices is one of the vital factors which have great influence on the device performance. Defect states in silicon oxynitride (SiO x N y ) buffer layer for organic photo devices can be controlled by introducing appropriate dopant materials. We performed ab initio simulations to identify the effect on doping SiO x N y with carbon (C), boron (B), and phosphorous (P) atoms. The results unveil that hole defects in the SiO x N y l

By promoting anabolism, MTORC1 is critical for muscle growth and maintenance. However, genetic MTORC1 upregulation promotes muscle aging and produces age-associated myopathy. Whether MTORC1 activation is sufficient to produce myopathy or indirectly promotes it by accelerating tissue aging is elusive. Here we examined the effects of muscular MTORC1 hyperactivation, produced by simultaneous depletion of TSC1 and DEPDC5 (CKM-TD). CKM-TD mice produced myopathy, associated with loss of skeletal muscl

Addressing the direct control of surface wettability has been a significant challenge for a variety of applications from self-cleaning surfaces to phase-change applications. Surface wettability has been traditionally modulated by installing surface nanostructures or changing their chemistry. Among numerous nanofabrication efforts, the chemical oxidation method is considered a promising approach because it allows cost-effective, quick, and direct control of the morphologies and chemical compositi

본 연구에서는 벤토나이트 슬러리의 전기적 특성에 대한 영향인자와 전기전도 메커니즘을 규명하고자 하였다. 벤토나이트 및 흙-벤토나이트 슬러리의 전기전도도는 벤토나이트 함량이 증가함에 따라 뚜렷한 선형적 증가 경향을 나타내어 전기전도도 측정기법이 슬러리에서의 벤토나이트 함량 평가에 적용될 수 있음을 확인하였다. 이때 슬러리의 전기전도도 변화는 주로 벤토나이트에 존재하는 양이온이 용해되어 용액의 전기전도도를 변화시키기 때문에 나타나는 결과로 확인되었다. 슬러리에서 벤토나이트 함량에 따른 전기전도도의 선형적 관계는 용액의 초기 전기전도도와 세립토 함량에 영향을 받는 것으로 나타났으며 이들의 영향을 고려하여 슬러리에서 벤토나이트 함량과 전기전도도와의 관계식을 도출하였다. 본 연구에서 제시된 관계식을 토대로 다양한 조건의 벤토나이트 및 흙-벤토나이트 슬러리에서 전기전도도 측정을 통하여 벤토나이트 함량에 대한 정량적인 평가가 가능할 것으로 기대된다.

Abstract A low-temperature laser crystallization is newly devised for producing polycrystalline silicon (poly-Si) thin films of low-loss, low surface roughness enough for nanoscale patterning, applicable to practical Si metasurface elements on complementary metal-oxide semiconductor (CMOS) electronic architectures in visible lights. The method is based on dielectric encapsulation of an amorphous Si film and subsequent laser-induced local crystallization. Such poly-Si thin film yields order-of-ma

Over the past decade, direct-push geotechnical sensors or penetration probes have earned widespread acceptance in the geoenvironmental fields of study as a more viable and cost-effective solution for the assessment of soil and groundwater contamination. Of these, resistance cone penetrometer (RCPT) devices equipped with electrical sensors have been successful in qualitatively locating contaminated areas. While the RCPT method has proved to be successful for delineating inorganic contaminants in

전기비저항콘은 현장에서 지반의 오염대를 조사하는데 상대적으로 경제적인 비용으로 적용될 수 있다. 그러나, 전기비저항 결과만에 의한 해석은 정량적 데이터베이스의 부족과 함수비 등의 다른 지반공학적 영향인자들에 의해 모호한 결과를 나타낼 수 있다. 본 연구에서는 지반오염조사에서의 전기비저항 측정기법을 보완하기 위하여 정전용량 측정기법을 도입하여 중금속과 유류로 오염된 지반에서의 적용성을 평가하고자 하였다. 함수비와 오염물질의 종류에 따른 전기비저항과 정전용량의 변화를 평가하기 위하여 실내모형시험을 수행하였으며, 그 결과 전기비저항과 유전상수를 동시에 측정하여 분석함으로써 오염대의 감지에 신뢰도를 높일 수 있는 것으로 나타났다. 전기비저항과 정전용량 측정기법은 중금속으로 오염된 포화지반과 지하수대 상부에 존재하는 디젤유 오염층을 감지하는 데 적용성이 높은 것으로 나타났다.

A column testing device capable of measuring the electrical resistivity of soil at 3 different locations was developed to verify applicability of bulk electrical conductivity (BEC) breakthrough curves in monitoring contaminant transport. Tracer injection tests were conducted with three different types of saturated sands to obtain average linear velocities and longitudinal hydrodynamic dispersion coefficients based on BEC breakthrough curves and effluent solute breakthrough curves. Comparative an