• Title/Summary/Keyword: 박종화

검색결과 393건 처리시간 0.024초

노이즈 차폐 변압기의 주파수 특성 분석 (A analysis of frequency characteristics for the noise cut transformer)

  • 김명석;오준식;조현길;한규환;박종화
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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    • pp.957-959
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    • 2005
  • A noise reduction equipment in power systems was device combined in a passive element such as the form of L, R and C. A analysis of frequency characteristics for the transformer models shall be considered the additional capacitance between the windings($C_{ps}$), terminals($C_s$), and winding-ground($C_g$). A noise in transformer is modeled by take account into the different frequency. In case of the high frequency, transformer windings with stray capacitance have lower impedance. Therefore a noise is transferred from primary winding to secondary winding. Noise Cut Transformer(NCT) was the noise reduction device and was normally single phase two-winding type transformer. We analyzed frequency characteristics using the nodal network analysis with the equivalent circuit and the simulation of the MATLAB.

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단락시험 회로정수 계산용 어플리케이션 개발 (The Development of Assistant Application for Short-circuit Tests)

  • 오승렬;나칠봉;박지훈;박종화
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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    • pp.131-133
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    • 2004
  • A improving method of the time efficiency to be necessary during the short-circuit tests that use high-priced equipment. Minimizing a human error through the database of relevant standards prospects a reliable tests. This paper describes the design concept and overall process of the development of the application that is developed in order to realize these functions.

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도시철도 지능형 카메라에 요구되는 성능 및 관련기술 연구 (Analysis of the Requirement on the Intelligent CCTV Camera in Subway Environment)

  • 장일식;박종화;김주선;김형민;박구만
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.1151-1156
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    • 2008
  • 본 논문에서는 복잡한 환경을 감시해야 하는 도시철도 서비스 구간 내 각종 사고를 예방하고, 사고 및 재난 발생 시 신속한 상황파악 및 대처를 통하여 피해를 최소화할 수 있는 능동적인 감시체계로 변환하기 위한 지능화된 종합감시 시스템을 개발하는데 있어, 요구되는 지능형 감시 카메라의 성능 및 관련기술을 분석하였다.

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제조산업 업무 능력 향상을 위한 가변적 시나리오 기반 XR 교육훈련 콘텐츠 제안 (Proposal of Variable Scenario-based XR Education and Training Content to Improve Manufacturing Industry Work Ability)

  • 길영익;박종화;임현규;김재희;전지혜
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2021년도 제64차 하계학술대회논문집 29권2호
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    • pp.627-628
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    • 2021
  • 본 논문은 제조 산업 현장에서의 업무 능력 향상을 위한 XR 교육훈련 콘텐츠의 가변적 시나리오를 제안한다. 가변적 시나리오를 적용한 XR 교육훈련 콘텐츠는 교육훈련 관리자가 자유롭게 시나리오를 가감할 수 있어 동일한 콘텐츠 내에서 다양한 시나리오로 콘텐츠를 구성할 수 있는 특징을 가진다. 이는 기존 하나의 시나리오로 반복되는 교육훈련의 한계를 해결할 수 있으며, 현장에서 발생할 수 있는 돌발적 상황 및 변화되는 업무 프로세스를 효과적으로 진행할 수 있을 것이다.

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딥러닝 기반 개인 보호장비 검출에 관한 연구 (A Study on Deep Learning Based Personal Protective Equipment Detection)

  • 박종화;전소연;전지혜;김재희
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2020년도 하계학술대회
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    • pp.650-651
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    • 2020
  • 본 논문은 YOLO v4 알고리즘을 이용하여 산업 현장에서 근로자의 개인 보호장비를 검출하는 방법을 제시한다. 학습데이터 주석은 사람 영역, 안전모, 안전 조끼 혹은 벨트 영역을 검출하도록 처리하였으며, 학습데이터 2,198개, 검증데이터 275개를 학습하는 데 이용하였다. 실험 결과 학습 반복 수 10,000번을 기준으로 81.81%의 mAP가 나옴을 확인하였다. 추후 정확도 개선을 위해 학습데이터 구축 및 전·후처리 알고리즘 관련 연구를 수행할 예정이다.

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프라이버시 보호를 갖는 확장된 역할기반 접근제어 모델 (An Extended Role-based Access Control Model with Privacy Enforcement)

  • 박종화;김동규
    • 한국통신학회논문지
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    • 제29권8C호
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    • pp.1076-1085
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    • 2004
  • 최근 프라이버시 적용이 IT분야의 가장 중요한 문제의 하나로 대두되고 있다. 프라이버시 보호는 조직의 데이터 처리 시스템에 프라이버시 정책을 적용함으로써 달성 될 수 있다. 전통적인 보안 모델은 다소간 프라이버시 바인딩과 같은 기본적인 프라이버시 요구를 적용하기에 부적절하다. 본 논문은 조직에 프라이버시 정책을 적용할 수 있는 하나의 확장된 역할기반 접근제어 모델을 제안한다. 이 모델은 RBAC과 도메인-타입 적용, 그리고 프라이버시 정책을 결합함으로써 프라이버시 보호와 함께 문맥기반 접근제어를 제공한다. 프라이버시 정책은 역할에 프라이버시 등급을, 데이터에 고객의 프라이버시 선호에 따른 데이터 프라이버시 등급을 부여하는 데이터 사용 정책을 적용함으로써 달성한다. 또 이 모델을 응용에 적용하기 위하여 작은 병원 모델이 사용되었다.

LANDSAT과 KOMPSAT-2 데이터를 이용한 청주지역 도시열섬효과의 평가 (Assessment of the Urban Heat Island Effects with LANDSAT and KOMPSAT-2 Data in Cheongju)

  • 나상일;박종화
    • 농업과학연구
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    • 제39권1호
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    • pp.87-95
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    • 2012
  • Land surface temperature (LST) is an important factor in human health, thermal environment, heat balance, global change studies, and as control for climate change. The objective of this study was to assess the influence of Urban Heat Island (UHI) Effects on the LST and NDVI in Cheongju, Korea. The aim was to evaluate the effect of urban thermal environment for LST comparison of satellite-derived and in situ measured temperature. In this study, LANDSAT TM and KOMPSAT scene were used. The results indicated that the minimum LST is observed over dense forest as about $21{\sim}25^{\circ}C$ and maximum LST is observed over industrial area of about $28{\sim}32^{\circ}C$. The estimated LST showed that industrial area, bare soils and built-up areas exhibit higher surface temperatures, while forest, water bodies, agricultural croplands, and dense vegetations have lower surface temperatures during the summer daytime. Result corroborates the fact that LST over land use/land cover (LULC) types are greatly influenced by the amount of vegetation and water bodies present. The LST of industrial area and urban center is higher than that of suburban area, so it is clearly proved that there are obvious UHIE in Cheongju.

원격탐사(RS) 기법을 이용한 충북지역 5개 토양과 갯벌토양의 분광반사특성 (Spectral Reflectance Characteristics for Five Soils at Chungbuk Prefecture and Tideland Soil Using Remote Sensing Technology)

  • 박종화;신용희;이상혁
    • 한국환경복원기술학회지
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    • 제6권1호
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    • pp.34-40
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    • 2003
  • The deterioration of agricultural environment, which is characterized by dryness and desertification of land, is one of the main reasons which explain the recent decrease of land productivity. To solve these environmental problems, it is very important to make clear the mechanism between soil, water, vegetation and temperature. The main objective of this study is to provide a soil surface information, which represent a soil reflectance spectrum, by remote sensing technology. The soil reflectance of the soil was measured using a spectro-radiometer in the wavelength range from 300nm to 1100nm. The results suggest that the reflectance properties of soils are related to their mineral composition and soil moisture. Increasing soil moisture resulted in an decrease in the rate of reflectance which leads to parallel curves of soil reflectance spectra.

자연형 소하천의 호안공법별 식생분포 조사 (Vegetation survey in nature-friendly small streams for each protection method)

  • 이강석;박진기;연규방;박종화
    • 농업과학연구
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    • 제38권2호
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    • pp.315-324
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    • 2011
  • Riparian vegetation distribution patterns and diversity relative to various fluvial geomorphic channel patterns, stream bank stabilization methods, and stream flow processes are described and interpreted for selected nature-friendly small stream bank protection of Goesan, central Korea. Idong Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods which was nature-friendly stream bank protection. The project aim to maintain or increase stream bank stabilization ecosystem goods and services while protecting downstream and stream bank ecosystem. A number of protecting methods which were a Flight of fieldstone, Vegetation block, Green river block, Stone net, Green environment block, Eco friendly cobble, Vegetation mat and Geo-green cell and Firefly block were applied on the bank of Idong stream. The stream sites have been monitored about vegetation conditions each method in 2007. We selected six points to separately investigate in left and right bank. The main purpose of this study was to find out suitable methods and to improve stream restoration techniques for ecosystem. On the stream bank, H environment block method (9.7) was the highest average of vegetation coverage and Firefly block method (3.87) was the lowest average in applied methods.

대도시에 있어 냉섬의 유형별 온도완화 효과 -대구광역시의 사례 연구- (Effect of Cool Islands on the Thermal Mitigation in Urban Area -Case Study of Taegu Metropolitan City-)

  • 박인환;장갑수;김종용;박종화;서동조
    • 한국조경학회지
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    • 제28권1호
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    • pp.11-18
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    • 2000
  • Taegu is notorious as hot and dry summer among Korea cities. One of the most important goals of the open space planning is to ameliorate urban climate of the city. The objective of this research is to evaluate the thermal mitigation effect of the cool islands in Taegu metropolitan city. Cool islands of this paper includes parks and rivers surrounded by or adjacent to urbanized areas. Based on the analysis of the thermal band of Landsat TM at May 17, 1997, the thermal mitigation effect of open spaces in the city could be summarized as follows ; Kumho river showed the largest mitigation effect in terms of the width of mitigation zone and temperature difference. Evaporation from wide water surface and evapo-transpiration from riparian grass land could bring into results. Significant mitigation effect of parks covered with forest can be observed. The temperature range of such parks were between 19.05$^{\circ}C$ and 19.44$^{\circ}C$ However, the thermal mitigation effect of Dalsung park and Apsan park was insignificant. The small size and high percentage of hard paving of the former and the relative low density of the residential areas adjacent to the latter could be the main reason. In conclusion, the thermal mitigation effect in urban ope spaces could be detectedby the employment of thermal band data of Landsat TM and GIS buffering technique.

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