• 한국전자통신학회논문지
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• 제19권3호
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• pp.531-538
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• 2024

수질 환경의 중요성이 강조되고 있는 가운데 광주광역시 도시 하천의 수질개선을 위한 수질 지표는 수생 생태계에 영향을 미치는 중요한 요소로 정확한 예측이 필요하다. 본 연구에서는 XGBoost와 LightGBM 머신러닝 알고리즘을 활용하여 광주천의 중요한 지점인 하류 평촌교(PyeongchonBr)와 상류 방학교(BangHakBr_Gwangjucheon1) 수계의 수질 검사 항목 중 통계적 검증 결과 유의미한 항목인 질소(TN), 질산염(NO3), 암모니아 양(NH3) 세 가지 수질 지표를 예측하는 연구를 수행하였고, 회귀 모델 평가 지표인 RMSE를 이용하여 예측 모델의 성능을 평가하였다. 수계별 개별적인 모델을 구현하여 교차 검증 후 성능을 비교한 결과, XGBoost 모델이 뛰어난 예측 능력을 보였다

• International Journal of Quality Innovation
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• 제6권1호
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• pp.35-42
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• 2005

The purpose of this paper is to clarify analytically the relation between the characteristics and the pricing of the products of individual manufacturers, so we can offer beneficial information for designing and developing products. Light trucks of 1 ton to 4 ton have been taken up as examples. We carried out analyses based on the information on the evaluations of the functional characteristics by surveying the specifications obtained from light truck catalogues.

• 한국인쇄학회:학술대회논문집
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• 한국인쇄학회 2007년도 추계 학술논문 발표회
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• pp.75-81
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• 2007

As manufacturing the low temperature firing paste applicable flat light source for LCD BLU, this study examined the specific quality. For the phosphor pastes, the low temperature firing acryl resin is used as the binder resin. As the result of thermal decomposition characteristics, residual hydroxylcarbon rested under 0.1wt% on 400$^{\circ}C$. With the manufactured paste in this study, the flat light source device is manufactured through the screen printing and it brought the almost 100% of special quality radiation about the phosphor brightness.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.280-283
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• 2004

Micro-lens patterned micro-mold fabrication method for Light Guiding Plate(LGP), kernel part of LCD-BLU(Back Light Unit), was presented. Instead of erosion dot pattern for LGP optical design, micro-lens pattern, fabricated by LIGA-reflow process, was applied. Optical pattern design method was also developed not only for negative pattern LGP, but also positive pattern LGP. During injection molding process, experimental study was conducted to improve replication quality and brightness of ${\sim}50um$ micro-lens pattern mold. The effect of mold temperature for the replication quality of micro-lens array was studied.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.159-166
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• 1999

In this paper, running performance analyses of an articulated light rail vehicle are carried out using VAMPIRE software package. The stability analysis to determine the critical speed and the safety analysis such as derailment coefficients, lateral forces of wheels and reduction of wheel load are carried for the track conditions of straight, transition and curving range to the operating velocity of 40km/h. Also, ride quality is analyzed. As the results of analysis, the safety of light rail vehicle satisfied with the limit values and the ride quality for tare and full load condition was shown to the "not uncomfortable" level in ISO 2631-1 (1997) criteria.

• 반도체디스플레이기술학회지
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• 제23권2호
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• pp.23-27
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• 2024

Underwater images are typically degraded due to color distortion, light absorption, scattering, and noise from artificial light sources. Restoration of these images is an essential task in many underwater applications. In this paper, we propose a two-phase deep learning-based method, Underwater Deep Curve Estimation (UWDCE), designed to effectively enhance the quality of underwater images. The first phase involves a white balancing and color correction technique to compensate for color imbalances. The second phase introduces a novel deep learning model, UWDCE, to learn the mapping between the color-corrected image and its best-fitting curve parameter maps. The model operates iteratively, applying light-enhancement curves to achieve better contrast and maintain pixel values within a normalized range. The results demonstrate the effectiveness of our method, producing higher-quality images compared to state-of-the-art methods.

• 한국식품과학회지
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• 제45권6호
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• pp.763-769
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• 2013

본 연구는 전자코를 이용하여 시판 콩기름의 휘발성분이 파장에 영향을 받는지 알아보고자 암실과 형광등 및 파장이 다른 LED 광원을 PE 용기에 조사하면서 12주 동안 변화되는 휘발성분의 패턴 변화를 분석하였다. 콩기름의 휘발성분의 변화는 저장기간동안 암실 처리구에서 가장 적고 천천히 일어났으며, 형광등 처리구에서 가장 크고 급격한 변화가 일어나는 것을 보여주었다. 저장 초기인 4주에는 형광등 처리구를 제외한 모든 처리구에서 미세한 변화가 일어났으며, 저장 12주에는 형광등 처리구 다음으로 파란색과 백색 LED 처리구에서 큰 변화를 보여준 반면 초록색 LED 처리구에서는 변화가 적었다. 파란색과 흰색 LED 처리구는 저장 12주째에서 급격한 휘발성분의 변화가 나타났다. 하지만 빨간색과 초록색 LED 조사 시에는 8주째에 급격한 휘발성분이 생성된 것에 비하여, 저장 12주째에는 휘발성분의 변화가 매우 감소하는 것을 보여주었다. 또한 초록색 LED 처리구에서 가장 적은 변화를 보였다. 이러한 결과를 토대로 볼 때 초록색 LED 광원에서 콩기름을 전시 판매하는 것이 바람직하며, 형광등과 파란색, 백색 LED 광원은 바람직하지 못한 것으로 판단된다. 또한, 전시 판매가 아니라면 암실에서 저장하는 것이 가장 바람직할 것으로 예상되는 바이다.

• Journal of Biosystems Engineering
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• 제34권1호
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• pp.37-43
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• 2009

Hyperspectral reflectance and fluorescence scattering have been researched recently for measuring fruit post-harvest quality and condition. And they are promising for nondestructive detection of fruit quality. The objective of this research was to develop a model, which measure the quality of apple by using hyperspectral reflectance and fluorescence. A violet laser (408 nm) and a quartz tungsten halogen light were used as light sources for generating laser induced fluorescence and reflectance scattering in apples, respectively. The laser induced fluorescence and reflectance of 'Golden Delicious' apples were measured by using a hyperspectral imaging system. Fruit firmness, soluble solids and acid content were measured using standard destructive methods. Principal component analyses were performed to extract critical information from both hyperspectral reflectance and fluorescence data and this information was then related to fruit quality indexes. The fluorescence models had poorer predictions of the three quality indexes than the reflectance models. However, the prediction models of integrating fluorescence and reflectance performed consistently better than the individual models of either reflectance or fluorescence. The correlation coefficient for fruit firmness, soluble solid content, and tillable acidity from the integrated model was 0.86, 0.75, and 0.66 respectively. Also the standard errors were 6.97 N, 1.05%, and 0.07% respectively.

• Journal of Multimedia Information System
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• 제8권2호
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• pp.93-100
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• 2021

Under the time-varying temperature, the high-temperature radiation of forgings and the change of reflection characteristics of oxide skin on the surface of forgings lead to the difficulty of obtaining images to truly reflect the geometric characteristics of forgings. It is urgent to study the clear and reliable acquisition method of hot forging feature image under time-varying temperature to meet the requirements of visual measurement of hot geometric parameters of forgings. Based on this, this chapter first puts forward the quality evaluation method of forging feature image, which provides guarantee for the accurate evaluation of feature image quality. Furthermore, the factors that affect the image quality, such as the radiation characteristics of forgings and the photographic characteristics of cameras, are analyzed, and the imaging spectrum which can effectively suppress the radiation intensity of forgings is determined. Finally, aiming at the problem that the quality of image acquisition is difficult to guarantee due to the drastic change of radiation intensity of forgings under time-varying temperature, an image acquisition method based on minimum signal-to-noise ratio (SNR) based laser light intensity adaptation is proposed, which significantly improves the definition of feature light strips in forging images at high temperature, and finally realizes the clear acquisition of feature images of large-scale hot forging under time-varying temperature.

• 한국작물학회지
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• 제32권4호
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• pp.386-391
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• 1987

재배광도와 재식밀도(40, 56, 90주/칸)가 인삼의 수량과 홍삼의 품질에 미치는 영향을 사양토산지삼포에서 수행하였다. 1. 20%의 광도는 수량이나 홍삼품질에서 5％ 관행광도에 이하여 유의차를 보이지 아니하였다. 2. 고광도는 줄기를 줄이고 엽면적을 적게 했으며 비엽중을 증대시켰으나 경직경이 적은 것으로 보아 조기낙엽의 피해 가능성이 있다. 3. 고광도는 엽록소함량을 적게 하였으나 Chl a /b값은 차이가 없었고 잎의 수분함량에 차이가 없었다(6 월 15일). 4 최대수량과 최대천지삼율을 나타내는 재식밀도는 칸당 64본으로 일치하였다. 5. 외관천지삼율은 천지삼율과 유의(P=0.01) 정 상관을 보였다. 6. 내백은 56 주구에서 유의성 있게 높았으며 백피는 90본에서만 유의성 있게 낮았다 7. 내공은 재식밀도와 유의성 있는 관계가 없어 밀식이 내공방지에 유효하다는 일반의 믿음과 일치하지 아니하였다.