• 전기학회논문지P
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• 제60권3호
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• pp.110-113
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• 2011

Platform Screen Door, PSD, is a device that seeks to prevent accidents with regards to falling off the platform and getting trapped between the trains, achieve improvements on the cleanliness of the air, address the accessibility issue of the disabled and the elderly and provide fresher environment on the platform in general. This is achieved by preventing health hazards and accidents from occurring through installation of fixed and moving doors between rail, tram and subway platforms and the railway. Domestic firms have achieved domestic production to a large degree in various Control Units including the Overall Control Unit and RF devices through investments in technology. Despite this, full domestic production of the core of the PSD system, Door Control Unit, DCU, is not yet achieved, having to install PSDs in a relatively short period of time. Currently, controllers with DC motors are developed for installation or one is faced with having to import foreign produced controllers. In this research, the control unit prototype using the BLDC motor was domestically produced. The performance of the control unit was rigorously tested through installation on Eun-Ha Rail on Wol-Mi Island.

• Journal of Information Display
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• 제4권3호
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• pp.6-11
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• 2003

We have fabricated a carbon nanotube field emission display (CNT-FED) panel with a 2-inch diagonal size by using a screen printing method and vacuum in-line sealing technology. The sealing temperature of the panel was around 390$^{\circ}C$ and the vacuum level was obtained with 1.4x$10^{-5}$torr at the sealing. When the field emission properties of a fabricated and sealed CNT-FED panel were characterized and compared with those of the unsealed panel which was located in a test chamber of vacuum level similar with the sealed panel. As a result, the sealed panel showed similar I-V characteristics with unsealed one and uniform light emission with very high brightness at a current density of 243 ${\mu}A/cm^2$, obtained at the electric field of 10 V/${\mu}m$.

• Corrosion Science and Technology
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• 제6권5호
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• pp.251-256
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• 2007

Plasma nitriding is a surface treatment process which is increasingly used to improve wear, fatigue and corrosion resistance of industrial parts. Active screen plasma nitriding (ASPN) has both the advantages of the classic cold wall and the hot wall conventional dc plasma nitriding (DCPN) method and the parts to be nitrided are no longer directly exposed to the plasma. In this study, AS plasma nitriding has been used to nitride the UNS S31803 duplex stainless steel, AISI 304 and AISI 316 austenitic stainless steel, and AISI 420 martensitic stainless steel. Treated specimenswere characterized by means of microstructural analysis, microhardness measurements and electrochemical tests in NaCl aerated solutions. Hardness of the nitride cases of AISI 420 stainless steel by Knoop test can get up to 1300 HK0.1. From polarization tests, the corrosion current densities of AISI 420 and UNS S31803specimens ASPN at $420^{\circ}C$ were generally lower than those of their untreated substrates. The corrosion resistance of UNS S31803 duplex stainless steel can be enhanced by plasma nitriding at $420^{\circ}C$ Cowing to the formation of the S-phase.

• 한국산업보건학회지
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• 제20권3호
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• pp.192-202
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• 2010

This study aimed to suggest the severity of indoor air pollutants in screen gold arenas which were not sufficiently investigated in Korea up to now and to help users to enjoy golf in more pleasant indoor environment. The indoor environment survey was conducted with 21 screen gold arenas in Seoul from Oct. 28, 2008 to March 13, 2009. Indoor air quality was measured and analyzed in accordance with the Air Pollution Process Test Method specified bu NIOSH(2005). The screen golf arenas are mostly in the underground floors in this study, 4 on the ground floors(19.0%) and 17 in the underground floors(81.0%). In the air in screen golf arenas, the geometric mean of benzene, toluene, ethylbenzene and xylene were 2.92 ${\mu}g/m^3$, 70.34 ${\mu}g/m^3$, 14.00${\mu}g/m^3$ and 31.43 ${\mu}g/m^3$, respectively, which exceeded the exposure limites. Each arena exceeded the exposure limit for one pollutant each. However, styrene didn't exceed the limit as 8.09 ${\mu}g/m^3$. Furthermore, the geometric mean of formaldehyde was 63.11${\mu}g/m^3$ and 7 arenas exceeded the limit. The geometric mean of volatile organic compounds(VOCs) was 428.41${\mu}g/m^3$ and 10 arenas exceeded the limit. For the density distribution of pollutants by location, benzene, toluene, ethylbenzene, xylene, styrene and formaldehyde showed higher density distribution in underground spaces, for which the statistically significant difference was not found. However, PM10 showed the statistically significant difference (p<0.05). In accordance with the analysis on the correlation between the density of pollutants in the screen golf arenas, Pearson correlation coefficient between ethylbenzene and styrene was 0.980, very significant correlation(p<0.01). The correlation coefficients between the density of toluene, ethylbenzene, xylene and styrene and that of VOCs were 0.543, 0.434, 0.451 and 0.459, respectively, which demonstrated the statistically significant difference (p<0.05).

• 방송공학회논문지
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• 제25권3호
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• pp.325-337
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• 2020

VVC(Versatile Video Coding)는 ISO/IEC/ITU-T의 JVET(Joint Video Experts Team)에서 표준화 중인 새로운 비디오 부호화 표준으로 스크린 콘텐츠 부호화 툴을 포함한 다양한 기술을 채택하고 있다. 스크린 콘텐츠는 문자 영역과 같이 사선 방향 에지가 자주 발생하는 특징을 가지며, 이런 특징을 갖는 영상에 삼각형 형태의 분할 부호화를 적용하면 압축 효율이 증가할 수 있다. 본 논문에서는 스크린 콘텐츠를 위한 VVC 기반 화면내 삼각형 분할 예측 방법을 제안한다. 기존 VVC의 화면간 예측 부호화에서 삼각형 분할 예측을 지원하는 Triangular Prediction Mode 방법과 유사하게, 제안 방법은 화면내 예측 부호화에서 수직과 수평 방향 예측 모드와 주변 복원 참조 라인을 이용하여 두 개의 사각형 예측 블록을 생성하고 삼각형 모양의 마스크로 두 예측 블록을 가중합하여 최종 예측 신호를 만든다. 제안 방법의 실험 결과는 All Intra 스크린 콘텐츠 영상 실험에서 YUV 각각 평균 1.86%, 1.49%, 1.55% 부호화 성능향상을 보이고, 자연 영상 실험 조건에서는 부호화 효율에 미미한 손실을 보였다. 결론적으로, 화면내 예측 부호화 모드에 제안 방법을 적용하여 압축 성능을 향상할 수 있었다.

• 한국철도학회논문집
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• 제9권6호
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• pp.784-791
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• 2006

This paper presents the test results to evaluate the healthiness of the ballast in subway. The test includes the dynamic load test in servicing Line the screen classification test of aggregates and the wear test. From the results, the aspect and the property of the ballast are evaluated. The dynamic load tests explain the relationship between the deterioration of the ballast and the fluctuation of loads. The assessment of impact factor based on the field test results in a good property of test blocks is proposed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.484-493
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• 2006

This paper is presented the test results to evaluate the healthiness of the ballast in subway. The test includes the dynamic load test in servicing Line the screen classification test of aggregates and the wear test. From the results, the aspect and the property of the ballast are evaluated. The dynamic load tests the relationship between the deterioration of the ballast and the fluctuation of loads. The assesexplain sment of impact factor based on the field test results in a good property of test blocks is proposed.

• 컴퓨터교육학회논문지
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• 제17권5호
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• pp.99-106
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• 2014

본 연구는 영어 단어 학습의 핵심 인지기능인 작업기억의 음운고리를 적극적으로 활용하게 하는 영어 단어 제시 방법이 무엇이고 이 방법이 외국어 학습 동기 정도에 따라 효과가 다르게 나타나는지를 두실험을 통해 검증하였다. 실험1에서 학습자에게 음운고리를 최소 3회 사용하게 하는 제시 방법과 1회 사용하게 하는 제시 방법 그리고 자신이 제시 횟수 및 제시 시간을 조정할 수 있는 조건을 제시하였다. 실험1결과 3회 제시 조건이 1회 제시 조건에 비해 학습효과가 더 높게 나타났다. 실험2에서 외국어 학습 동기가 높은 집단과 낮은 집단에게 3회 제시 조건과 자기 조절 조건을 제시하여 학습 효과를 검증하였다. 실험2결과 고-동기 집단의 경우 제시 방법에 따른 학습의 정도는 차이가 없었지만, 저-동기 집단의 경우 자기 조절 조건에서 더 좋은 성과를 보였다. 이에 본 연구는 논의에서 컴퓨터 및 디지털 환경에서 영어 단어를 어떻게 제시해야 학습효과가 증진될 수 있는지를 제안하였다.

• 대한인간공학회지
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• 제35권3호
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• pp.125-133
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• 2016

Objective: The aim of this study is to figure out the level of Functional Movement Screen (FMS) of 122 automobile manufacturing workers and to set the FMS score for predicting risk of musculoskeletal disorders. Background: Although today's industrial sites have been becoming automated rapidly, the risks of work-related musculoskeletal disorders (WMSDs) have been on the rise. In the case of WMSDs, it is important to control WMSDs at the early stage. Early detection of WMSDs is very important for the successful treatment. However, the medical examination puts a great financial burden on most workers. To reduce their burden, there is one test to check the musculoskeletal functional condition and to predict the risk of injury, which is called FMS. Method: This research tested the FMS score of 122 workers at a motor company, and also conducted a questionnaire survey of individual characteristics and job characteristics. Results: For the 122 subjects, the average score of FMS is $14.63{\pm}2.27$. There is a negative correlation between FMS and their ages and BMI (p <0.05). FMS is higher when exercising regularly (p <0.05). The FMS scores of musculoskeletal disorder patients are lower than those of normal workers (p <0.05). While it is more likely to become a musculoskeletal disorder patient when FMS score is less than 14, it is more likely to become a normal worker when FMS score is more than or equal to 14. Conclusion: According to the result of FMS test, there is a score difference between individuals with musculoskeletal disorders and normal ones. FMS scores can also predict and identify workers with risk of the musculoskeletal disorders. Application: According to this study, FMS can be expected to have a positive effect on the prevention of WMSDs in worksites.

• 교육녹색환경연구
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• 제14권2호
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• pp.37-44
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• 2015

2005년 "학교폭력 및 예방에 관한 법률"이 제정되면서 학교에 CCTV가 설치 운영되고 있다. 하지만 실제 학교현장에서는 CCTV 설치보다는 운영상의 모니터링 환경에 있어 문제점들이 발생하고 있다. 본 연구는 상기 문제점들 중 가장 큰 문제점인 CCTV 감시환경에 따른 적합한 모니터의 크기를 산정할 수 있는 모델을 제시함에 있다. 이를 위해 첫째, 선행연구를 통해 CCTV의 기본적 원리 및 적정 모니터링에 대한 기준을 분석한다. 둘째, 실태조사를 실시하여 실제 학교현장에서의 CCTV 모니터링 운영현황을 분석한다. 셋째, 국내 경비인력의 일반적인 시력을 기준으로 CCTV 사양 등에 따른 모니터의 출력크기를 산정할 수 있는 산정식과 적정한 모니터 크기를 산정할 수 있는 모델을 제시한다. 결론적으로 대부분의 학교현장에 설치된 CCTV를 고려하여 4개 분할화면의 모니터링을 적용하기 위해서는 최소 27인치의 모니터가 필요하다는 결과를 도출하였다.