• 조명전기설비학회논문지
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• 제12권2호
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• pp.121-128
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• 1998

새로운 형태의 자기식 형광등 안정기를 설계 개발하여 고효율화 성능시험을 수행하였다. 새로운 철심재료인 고성능의 G-9 재료를 사용하고, 철심구조와 모양을 개선하였고 코일의 동선을 짧고 굵은 것으로 대체하여 직류저항 성분을 줄여서 안정기 자체의 에너지 손실을 감소시켰다. 반도체형 점등회로를 대폭 개선하여 순간 점등을 가능하게 하고 형광램프의 사용수명연장, 화재방지 등을 할 수 있게 하였다. 안정기 자체의 에너지 감소가 1.7Watt, 형광등 조명광 향상이 7.6[%] 증가 등 큰 에너지 절약을 보였다. 본 연구결과는 형광등 안정기의 기술 향상과 국가 전력소비 절감효과 등 중요한 의미가 있다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권5호
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• pp.352-357
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• 2000

This paper presents about an example of circuit design and characteristics of inverter according to the variable capacitance of the DC voltage source separation capacitor used in ZVS-HB type high frequency resonant inverter. The soft switching technology known as ZVS is used to reduce turn off loss at switching. In the event the capacitance of the DC voltage source separation capacitor is varied, the analysis of inverter circuit has generally described by using normalized parameter and operating characteristics have been evaluated in terms of switching frequency and parameters. According to the calculated characteristics value, a method of the circuit designs and operating characteristic of the inverter is also presented in this paper. In addition, this paper proves the validity of theoretical analysis through the experiment. This proposed inverter shows that it can be practically used in future as power source system for the lighting equipment of discharge lamp, DC-DC converter etc.

• 조명전기설비학회논문지
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• 제26권10호
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• pp.95-101
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• 2012

Typically, large scale power generation facilities are linked to 345kV transmission line through a step-up transformer. If the value of transient voltage by generating lightning stroke is large more than electric equipment's BIL, devices insulation is destroyed. LA(Lighting Arrester) is used as a main means of prevention. However, the installation of LA takes the constraints of installation place and expensive installation costs. Therefore, we need to carefully study whether installation of installation can be omitted and the most efficient place of installation. In this paper, we simulated the transient voltage detected by lightning stroke at each equipments in the 345kV transmission power grid by using EMTP-RV program.

• 조명전기설비학회논문지
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• 제12권4호
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• pp.55-61
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• 1998

일반적으로 접지시스템에서 접지저항계산은 저주파수의 전원이 대지에 인가될 때 발새외는 대지전위상승을 측정하여 계산한다. 그러나 뇌격과 써지 엄펄스와 같은 고주파수에 해당하는 전원에 대해서는 현재의 접지 시스템에서 고려하고 있지 않기 때문에 전기설비에 매우 큰 영향을 미칠 우려가 있다. 그래서 이 논문에 서는 뇌격이 전극봉에 인가되었을 때 발생되는 접지 임피던스의 과도현상을 실험하였다. 그리고 이 실험 결과는 이론적 해석과 잘 일치하였으며 지중방전현상이 임펄스 임피던스 저감에 영향올 미친다는 사실을 확인 할 수 있었다.

• 한국태양에너지학회 논문집
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• 제34권3호
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• pp.1-11
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• 2014

The Korean government plans to introduce the building energy performance standard which regulates the annual energy consumption of buildings. This paper aimed to set up the reference building from database based on the building design trends for non-residential buildings. We surveyed the design data of 435 non-residential buildings which were granted building permission from 2007 to 2011. And we conducted estimation on the heating & cooling load and the energy consumption of the reference building using ECO2 program. From results, the reference building of non-residential buildings was office building which had a total 7 floors and $20,838m^2$ gross floor area. And it suggests the design reference data of building envelope, HAVC, heat source equipment and lighting system for the reference building. The total annual energy use of the reference building was $151.9kWh/m^2yr$.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.277-290
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• 2019

The demand for indoor positioning is increasing day by day. However, the widely used positioning methods today cannot satisfy the requirements of the indoor environment in terms of the positioning accuracy and deployment cost. In the existing research domain, the localization algorithm based on three-dimensional space is less accurate, and its robustness is not high. Visible light communication technology (VLC) combines lighting and positioning to reduce the cost of equipment deployment and improve the positioning accuracy. Further, it has become a popular research topic for telecommunication and positioning in the indoor environment. This paper proposes a surface centroid TOA localization algorithm based on the VLC system. The algorithm uses the multiple solutions estimated by the trilateration method to form the intersecting planes of the spheres. Then, it centers the centroid of the surface area as the position of the unknown node. Simulation results show that compared with the traditional TOA positioning algorithm, the average positioning error of the surface centroid TOA algorithm is reduced by 0.3243 cm and the positioning accuracy is improved by 45%. Therefore, the proposed algorithm has better positioning accuracy than the traditional TOA positioning algorithm, and has certain application value.

• 전기전자학회논문지
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• 제23권3호
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• pp.826-831
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• 2019

소형 독립형 태양광 전원장치는 조명장치, CCTV 등에 많이 활용되고 있다. 이러한 장치가 경쟁력을 가지기 위해서는 배터리와 같은 전력저장장치 수명이 매우 중요하다. 하이브리드 커패시터는 고밀도와 장수명의 장점을 가지고 있다. 본 논문에서는 하이브리드 커패시터를 이용한 독립형 태양광 전원장치를 제안한다. 전력변환장치의 구성하기 위해 하이브리드 커패시터의 충방전 특성 및 내부저항을 측정하였다. 일사량 변화에도 안정적인 최대 출력점 추종제어 알고리즘을 제시하였다. 제시한 시스템의 타당성을 검증하기 위해 18W의 하이브리드 커패시터와 10W태양광 전지를 이용하여 시제품을 제작하고 실험하였다.

• 한국산업융합학회 논문집
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• 제26권1호
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• pp.105-112
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• 2023

We analyze the global market for flexible electronic circuits, technical considerations, and analyze the market for application areas and regions. In the market analysis of the application field, the display field has the greatest influence in terms of market size and annual growth rate, and the OLE D lighting market size is expected to grow by nearly 50% in 2026. The multilayer flexible electronics, which dependently requires the semiconductor technology, has a larger market size than other structures and its growth rate is relatively large, leading the market and will be further analyzed in depth. The market size of multilayer flexible electronics applied to display field is expected to show an annual growth rate of 21.1% from $2.7 billion in 2017 to $9.8 billion in 2026, and the OLED market is expected to grow by 75.2% during the same periods. Recently, as electronic products have been miniaturized and advanced, and robust installation in a small space is required, companies that preoccupy multilayer structure or rigid flexible electronic circuit technology have an advantage in competitiveness, so many companies are trying to obtain this technology. These efforts are systematically supported by many countries because they can achieve mutual growth by strengthening the competitiveness of the application field and the same industry. In the case of Korea, a support system is established, but it is required to expand and activate it, and to localize manufacturing equipment and materials.

• 한국산업정보학회논문지
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• 제15권2호
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• pp.69-81
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• 2010

LCD 모니터의 백라이트로 CCFL 형광체를 많이 사용하고 있으나 그 불량여부는 육안에 의존하고 있다. 육안 검사를 함으로써 부품에 대한 일관성 있는 검사가 결여되고, 노동집약적인 검사로 인해 산업적 재해가 발생할 수 있다. 따라서, CCFL 불량유무를 판별하기 위해서 물리적 촬영 환경과 영상처리 알고리즘은 중요하다. 본 논문에서는 CCFL 형광체를 검사하기 위한 촬영환경에 대하여 설명하고, 촬영환경 중 돔 근거리 조명과 점원거리 조명에서의 몇 가지 불량판별 알고리즘을 제시하였다. 불량을 포함한 CCFL 형광체를 사용하여 실험을 수행하였고, 그 결과 제안한 촬영환경과 알고리즘은 불량 판별율 98.32 %와 과검율 4.88 %의 성능을 나타내었다.

• 대한치과기공학회지
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• 제22권1호
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• pp.89-112
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• 2000

Although dental laboratory technicians are prone to be exposed to various work-related health hazardous materials such as dusts, chemicals, etc., the prevalence and nature of work-related health problems of them have not been a matter of great concern in the field of occupational health service in Korea. The purpose of the present investigation was to describe a collected profile of subjective health symptoms and their attributable factors in Korean dental laboratory technicians. A questionnaire listing five groups of health symptoms and five health symptom-related factors was mailed to randomly selected 1,900 dental laboratory technicians. Among them, 1,344 dental laboratory technicians filled out the questionnaires and returnde them. Five groups of health symptoms included musculoskeletal symptom, dermal symptoms, respiratory symptoms, eys symptoms, and ear symptoms. Five health symptom-related factors were occupational environment-related health risk factors, work history, health related habits and status, use of personal protective equipment and general characteristics. Detailed parameters of health risk factors were work posture, vibration, and chemical or physical hazards such as dust, fume, vapor, solvent, light, and noise for occupational environment-related factors; work place, area, number of employees, work hours, career, work part, and work load for work history; Broca's index, hours of sleep, eating, smoking, alcohol, exercise, health examination, and self assessed health status for health habits and status; face masks, goggles, and so on for use of personal protective equipment, and; age, sex, marital status, and education for general characteristics. Before the start of main survey, a pilot survey was carried out for validity and reliability tests of the questionnaire. All the data obtained were coded and analyzed with PC/SAS 6.12 program. The prevalence of health symptoms was the highest in musculoskelton (87.3%), and followde by eyes (78.9%), respiratory organs (64.3%), ears (57.8%), and skin (52.2%) in descending order. Statistically significant risk factors by multiple logistic regression analyses were sex, health examination, self assessed health status, and hand/finger posture in musculoskeletal symptoms; sex, self assessed health status, career, acid gas, and hand contact with resin mixture in deraml symptoms; Broka's smoking, exercise, self assessed health status, and face mask in respiratory symptoms; sex, hours of sleep, self assessed health status, work hours, work load, plaster dust, inadequate lighting, and goggle in eys symptoms, and eating, smoking, self assessed health status, and work load in ear symptoms. With the above considerations in mind, prevalence of subjective symptoms among Korean dental laboratory technicians was relatively high, and they were attributable to most of the occupational environment-related factors, work history, use of personal protective equipment, health habits and status, and general characteristics. Particularly, it is suggested that health promotion programs for promoting self- assessed health status and smoking cessation, preventive measures for protection of the female technicians’health, and reducing work load be necessary, since those factors were associated with more than one subjective symptom.