염료감응형 태양전지의 전자재결합 방지를 위한 균일한 TiO₂ 차단층의 제조

배주원,구본율,이태근,안효진,Bae, Ju-won,Koo, Bon-Ryul,Lee, Tae-Kuen,Ahn, Hyo-Jin 한국분말야금학회 2018 한국분말재료학회지 (KPMI) Vol.25 No.1

Uniform $TiO_2$ blocking layers (BLs) are fabricated using ultrasonic spray pyrolysis deposition (USPD) method. To improve the photovoltaic performance of dye-sensitized solar cells (DSSCs), the BL thickness is controlled by using USPD times of 0, 20, 60, and 100 min, creating $TiO_2$ BLs of 0, 40, 70, and 100 nm, respectively, in average thickness on fluorine-doped tin oxide (FTO) glass. Compared to the other samples, the DSSC containing the uniform $TiO_2$ BL of 70 nm in thickness shows a superior power conversion efficiency of $7.58{\pm}0.20%$ because of the suppression of electron recombination by the effect of the optimized thickness. The performance improvement is mainly attributed to the increased open-circuit voltage ($0.77{\pm}0.02V$) achieved by the increased Fermi energy levels of the working electrodes and the improved short-circuit current density ($15.67{\pm}0.43mA/cm^2$) by efficient electron transfer pathways. Therefore, optimized $TiO_2$ BLs fabricated by USPD may allow performance improvements in DSSCs.

엣지 컴퓨팅 환경에서 적용 가능한 딥러닝 기반 라벨 검사 시스템 구현

배주원,한병길,Bae, Ju-Won,Han, Byung-Gil 대한임베디드공학회 2022 대한임베디드공학회논문지 Vol.17 No.2

In this paper, the two-stage object detection approach is proposed to implement a deep learning-based label inspection system on edge computing environments. Since the label printed on the products during the production process contains important information related to the product, it is significantly to check the label information is correct. The proposed system uses the lightweight deep learning model that able to employ in the low-performance edge computing devices, and the two-stage object detection approach is applied to compensate for the low accuracy relatively. The proposed Two-Stage object detection approach consists of two object detection networks, Label Area Detection Network and Character Detection Network. Label Area Detection Network finds the label area in the product image, and Character Detection Network detects the words in the label area. Using this approach, we can detect characters precise even with a lightweight deep learning models. The SF-YOLO model applied in the proposed system is the YOLO-based lightweight object detection network designed for edge computing devices. This model showed up to 2 times faster processing time and a considerable improvement in accuracy, compared to other YOLO-based lightweight models such as YOLOv3-tiny and YOLOv4-tiny. Also since the amount of computation is low, it can be easily applied in edge computing environments.

Sn-Doped In₂O₃ 나노잉크를 위한 나노로드의 복합화에 따른 용액기반 투명 전도성 산화물의 저온성능

배주원,구본율,이태근,안효진,Bae, Ju-Won,Koo, Bon-Ryul,Lee, Tae-Kun,Ahn, Hyo-Jin 한국재료학회 2017 한국재료학회지 Vol.27 No.3

Transparent conducting oxides (TCOs) were fabricated using solution-based ITO (Sn-doped $In_2O_3$) nanoinks with nanorods at an annealing temperature of $200^{\circ}C$. In order to optimize their transparent conducting performance, ITO nanoinks were composed of ITO nanoparticles alone and the weight ratios of the nanorods to nanoparticles in the ITO nanoinks were adjusted to 0.1, 0.2, and 0.5. As a result, compared to the other TCOs, the ITO TCOs formed by the ITO nanoinks with weight ratio of 0.1 were found to exhibit outstanding transparent conducting performance in terms of sheet resistance (${\sim}102.3{\Omega}/square$) and optical transmittance (~80.2 %) at 550 nm; these excellent properties are due to the enhanced Hall mobility induced by the interconnection of the composite nanorods with the (440) planes of the short lattice distance in the TCOs, in which the presence of the nanorods can serve as a conducting pathway for electrons. Therefore, this resulting material can be proposed as a potential candidate for solution-based TCOs for use in optoelectronic devices requiring large-scale and low-cost processes.

안티몬 도핑된 주석 산화물 투명전도막의 몰 농도에 따른 치밀한 표면 구조 제조

배주원,구본율,안효진,Bae, Ju-Won,Koo, Bon-Ryul,Ahn, Hyo-Jin 한국분말야금학회 2018 한국분말재료학회지 (KPMI) Vol.25 No.1

Sb-doped $SnO_2$ (ATO) transparent conducting films are fabricated using horizontal ultrasonic spray pyrolysis deposition (HUSPD) to form uniform and compact film structures with homogeneously supplied precursor solution. To optimize the molar concentration and transparent conducting performance of the ATO films using HUSPD, we use precursor solutions of 0.15, 0.20, 0.25, and 0.30 M. As the molar concentration increases, the resultant ATO films exhibit more compact surface structures because of the larger crystallite sizes and higher ATO crystallinity because of the greater thickness from the accelerated growth of ATO. Thus, the ATO films prepared at 0.25 M have the best transparent conducting performance ($12.60{\pm}0.21{\Omega}/{\square}$ sheet resistance and 80.83% optical transmittance) and the highest figure-of-merit value ($9.44{\pm}0.17{\times}10^{-3}{\Omega}^{-1}$). The improvement in transparent conducting performance is attributed to the enhanced carrier concentration by the improved ATO crystallinity and Hall mobility with the compact surface structure and preferred (211) orientation, ascribed to the accelerated growth of ATO at the optimized molar concentration. Therefore, ATO films fabricated using HUSPD are transparent conducting film candidates for optoelectronic devices.

비지도 학습 기반 Anomaly Detection을 위한 Autoencoder 모델의 손실 함수 적용에 대한 연구

배주원(Ju-Won Bae),정윤수(Yun-Su Chung),남승우(Seung-Woo Nam),한병길(Byung-Gil Han) 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.6

공장에서 생산된 제품의 정상 상태와 이상 상태를 구분하기 위해 Autoencoder를 사용한 비지도 학습에 대한 연구가 많이 이루어지고 있다. 비지도 학습은 데이터 수집에 필요한 시간과 비용을 크게 줄일 수 있다는 장점이 있으나, 일반적으로 비정상 데이터를 학습하지 않기 때문에 지도 학습 기반의 이상 탐지보다는 정확도가 낮은 편이다. 비지도 학습의 성능을 높이기 위해 본 논문에서는 Autoencoder를 사용하여 CE(Cross Entropy), MSE(Mean Squared Error), SSIM(Structural Similarity Index Map)과 같은 다양한 손실 함수(Loss Function)를 적용해서 이상 탐지 모델의 학습 성능을 비교한다. 비교 결과 CE 함수를 사용할 때 가장 정확한 출력 이미지를 만들어냈음을 확인했으며, SSIM의 경우 입력 이미지의 구조적인 특징에 집중하여 이미지를 생성하기 때문에 이상 검출을 위한 기준값 설정을 쉽게 수행할 수 있다는 점을 확인하였다.

전기변색 성능 향상을 위한 바나듐산화물 막의 결정성 제어 효과

김규호,배주원,이태근,안효진,Kim, Kue-Ho,Bae, Ju-Won,Lee, Tae-Kuen,Ahn, Hyo-Jin 한국재료학회 2019 한국재료학회지 Vol.29 No.6

In the present study, vanadium oxide($V_2O_5$) films for electrochromic(EC) application are fabricated using sol-gel spin coating method. In order to optimize the EC performance of the $V_2O_5$ films, we adjust the amounts of polyvinylpyrrolidone(PVP) added to the solution at 0, 5, 10, and 15 wt%. Due to the effect of added PVP on the $V_2O_5$ films, the obtained films show increases of film thickness and crystallinity. Compared to other samples, optimum weight percent(10 wt%) of PVP led to superior EC performance with transmittance modulation(45.43 %), responding speeds(6.0 s at colored state and 6.2 s at bleached state), and coloration efficiency($29.8cm^2/C$). This performance improvement can be mainly attributed to the enhanced electrical conductivity and electrochemical activity due to the increased crystallinity and thickness of the $V_2O_5$ films. Therefore, $V_2O_5$ films fabricated with optimized amount of PVP can be a promising EC material for high-performance EC devices.

초음파 분무 열분해법을 이용한 NiCrAl 합금 폼에 코팅된 불소 도핑된 주석 산화물의 영향

신동요,배주원,구본율,안효진,Shin, Dong-Yo,Bae, Ju-Won,Koo, Bon-Ryul,Ahn, Hyo-Jin 한국재료학회 2017 한국재료학회지 Vol.27 No.7

Fluorine-doped tin oxide (FTO) coated NiCrAl alloy foam is fabricated using ultrasonic spray pyrolysis deposition (USPD). To confirm the influence of the FTO layer on the NiCrAl alloy foam, we investigated the structural, chemical, and morphological properties and chemical resistance by using USPD to adjust the FTO coating time (12, 18, and 24 min). As a result, when an FTO layer was coated for 24 min on NiCrAl alloy foam, it was found to have an enhanced chemical resistance compared to those of the other samples. This improvement in the chemical resistance of using USPD NiAlCr alloy foam can be the result of the existence of an FTO layer, which can act as a protection layer between the NiAlCr alloy foam and the electrolyte and also the result of the increased thickness of the FTO layer, which enhances the diffusion length of the metal ion.

Japanism을 반영한 패션 디자인 전개에 관한 비교 연구

이은령(Lee Eun Lyeong),배주원(Bae Ju Won),이경희(Lee Gyeong Hui) 한국복식학회 2004 服飾 Vol.54 No.2

The purpose of this comparative study what is the way to express difference fashion design between The design data were 422 pictures of contemporary fashion designs which represented the Japanism Japanese fashion designers and Western fashion designers in the 1990s. style design from fashion collections and analyzed by literature study and classification categories. The results were as follows : 1) Early general Japanism expression was directly borrowed from traditional fashion design elements and has changed indirectly with fashion trend. 2) Japanese fashion designers have used color. fabric, and pattern than shape to express Japanese traditional images. 3) Western fashion designers have directly borrowed aesthetic elements of Kimono design, that is, layering, bending, neck-line, sleeve, and traditional Japanese men`s wear to express Japanism.