• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.318-320
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• 1999

Electric motor transforms electric power into mechanical power. It is important to increase efficiency of motor to save energy and to decrease operating cost. In this paper, some parameters and losses of high-efficiency induction motor and standard induction motor are measured by blocked-rotor test and no-load test. Operational parameters of high-efficiency induction motor that are compared with those of standard motor.

• 수산경영론집
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• 제34권1호
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• pp.45-67
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• 2003

Main target of fishing policy was enlargement of fishing catches in Korea after 1960s. This has caused sustainable decrease of the amount on the fisheries resource. In the result, fishing managements in Korea have suffered from aggravation of management. In this research, it is estimated the technical efficiency on Korean Off-shore Stow Nets Fishery that was made publication by Farrel in 1957. According to the analysis, Its were excessive to the gap of technical efficiency among Korean Off-shore Stow Nets Fishing boats. The gaps were excessive not only among each fishing managements but also by tonnage class and by region. Then we can recognize we need the change of Fishing Policy. That is, we should change for main target of fishing policy from enlargement of fishing catches to the policy of Price. And we should consider the supply of standard tonnage boats and specialization of fisheries by regions.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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• pp.99-102
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• 1999

The object of this paper is design and to make a high efficiency magnetic ballast for high pressure sodium lamp. The results show the efficiency is 10[%] up compared with standard ballast in best case.

• 한국산림과학회지
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• 제102권3호
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• pp.390-397
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• 2013

본 연구는 비모수추정 방법인 자료포락 기법을 이용하여 청양, 공주, 부여 등 충남지역의 밤나무 재배임가를 대상으로 경영효율성을 평가하였다. 분석자료는 2012년 3월부터 10월까지 실시한 '|밤나무 경영에 관한 실태조사'결과 중에서 20개 임가의 투입요소(관리비, 수확비, 재료비, 간접비, 재배면적)와 산출요소(조수입액)를 대상으로 하였다. 그리고 DEA 기법중 CCR 모형과 BCC 모형을 이용하여 기술효율성, 순수기술효율성, 규모효율성을 분석하였고 비효율성 임가의 개선방안도 제시하였다. 추가적으로 DEA 분석결과의 검증을 위하여 기술효율성과 표준진단표 결과를 비교하였다. 연구결과, 기술효율성은 평균값이 0.667로 전체적으로 비효율적으로 분석되었고 그 원인은 순수기술효율성이 평균 0.944, 규모효율성이 평균 0.703으로 나타나 재배기술적인 측면에서는 순수기술효율성이 높았지만 규모의 효율성에서는 비효율성이 존재하였다. 효율성이 1인 임가는 기술효율성 6개, 순수기술효율성 13개, 규모효율성이 6개 임가로 나타났고, 3개 모두 1인 임가는 6개로 나타났다. 표준진단표 점수와 비교한 결과 80점이상 고득점을 기록한 임가는 5개로 나타났고 이 중 기술효율성이 1로 분석된 임가는 3개로 나타났다. 또한 기술효율성과 표준진단표의 최저점수와 최고점수를 기록한 임가도 동일하게 나타났다. 이것은 DEA를 이용한 경영 효율성 평가가 표준진단표와 함께 현장에 적용 가능하다는 것을 나타낸다.

• 한국실내디자인학회논문집
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• 제25권6호
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• pp.40-51
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• 2016

The aim of this study is to quantitatively deduce the circulation efficiency and space arrangements of the outpatient department in geriatric hospitals in terms of spatial structure and to find a methodology that could promote the improvement of accessibility and spatial cognition while using the facilities. All space units of the selected twelve geriatric hospitals were located on the first floor. The study adopted the psychological distance concept of space syntax to the unitized spaces, and presented a set of indices, such as TD, PN, RF, PNT and TRF. These indices were calculated according to the standard clinical use procedures. The study evaluated the effectiveness of circulation. The analysis of circulation was based on the four major geriatric illnesses that were selected in this study. The study established the standard clinical use procedure with consideration of the medical treatment, examinations and space units of outpatient departments. The results are as follows: 1) Based on the statistical data, four major geriatric illnesses are examined, and space requirement and standard procedures are established. Development indicators are applied in order to quantitatively deduce the efficiency of spatial cognition. 2) The percentage of the risk of cognitive decline(TRF) has an inversely proportional correlation to the circulation efficiency(PNT) at a certain point. TRF is more influenced by the clinical use procedure than the scale. 3) The arrangement of the waiting space and types of corridor greatly affect the percentage of the risk of cognitive decline. 4) Vulnerable facilities are selected on the basis of the evaluation, and two alternatives that could promote the circulation efficiency are presented. The result of the reanalysis showed that cognitive efficiency had much improved compared to the existing facilities.

• 농업과학연구
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• 제33권2호
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• pp.179-193
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• 2006

Technical efficiency of semiforcing watermelon growers is 0.8248 on average, and distributed between 0.6744 and 0.9268. The result showed that semiforcing watermelon growers had by 18% of technical inefficiency and could be assumed that increasing technical efficiency could induce watermelon production more increase. Consequently, if growers' technical efficiency were improved while other environments were constant, watermelon production could be increased. Following the results from the inefficiency effect model, all assumption coefficient such as growers age etc, are significant at 10% level. Estimate of dispersion parameter ${\gamma}$ is 0.89, which confirms those differences between practical output and frontier output were derived from the technical efficiencies among growers. Differences of production system between high and low level growers in production efficiency were showed at side altitude, ventilation and heat-retaining in section of facilities and automation, soil test and calcium application in section of environment management, transplant preparation and duration of pollination in section of crop management and shipment place, sorting degree and management record analysis in section of business management respectively. As a result of analyzing consulting data by using standard diagnosis table of watermelon cultivation under structure which cultivated on semi-forced watermelon growers, gap between high and low level growers was 7.0 points in facility automation section, 7.1 points in environment section, 8.8 points in crop management section and 13.6 points in business management section, respectively, which were the biggest one among them. In case of excluding information-related items from the evaluation index of business management section, changes of business achievement are to occur. Therefore, it is recommended for us to review the standard diagnostic table of watermelon cultivation under structure by dividing evaluation index of management section into management and information.

• Nuclear Engineering and Technology
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• 제52권11호
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• pp.2601-2606
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• 2020

In this study, we expanded the performance of the existing EXVol code and performed empirical experiments and calculations. A high-resolution gamma spectroscopy system was constructed, and a standard point source and a standard volume source were measured with an HPGe detector with 43.1% relative efficiency. EXVol was verified by quantitative comparison of the detection efficiencies determined by measurements and calculations. To introduce the concept of the detector scanning that occurs in the actual measurement into the EXVol code, a collimator was placed between the source and detector. The detection efficiency was determined in the asymmetric arrangement of the source and detector with a collimator. A collimator made of lead with a diameter of 15 mm and a thickness of 50 mm was installed between the source and the detector to determine the detection efficiency at a specific location. The calculation result was contour plotted so that the distribution of detection efficiency could be visually confirmed. The relative deviation between the measurements and calculations for the coaxial and asymmetric structures was 10%, and that for the collimation structure was 20%. The results of this study can be applied to research using γ-ray measurements.

• 한국태양에너지학회 논문집
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• 제28권6호
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• pp.70-77
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• 2008

The purpose of this study evaluates a feasibility and economical efficiency of new renewable energy. According as weather change is serious problem now days, every people make attention to the reduction of greenhouse gas. The revitalization of new renewable energy creates the variety of energy source, stability of energy supply and reduction of greenhouse gas. In this study evaluates a feasibility and economical efficiency from new renewable energy of various photo voltaics, wind power, small hydro and biogas. Feasibility does in standard of technical characteristic, politic support, marketability, establishment present condition and development aim. Economical efficiency does in standard of developmental unit cost, utilization factor, equipment life, politic support cost, interest ratio. The results of this study were as follows photo voltaics, wind, small hydropower, biogas in order feasibility is high. Developmental unit cost, utilization factor, equipment life, politic support cost and analyzed the relationship of interest ratio fluctuation and economical efficiency. From all new renewable energy the utilization factor most is important in economical efficiency but necessary utilization factor is difficult because environmental problem.

• 청정기술
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• 제23권2호
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• pp.181-187
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• 2017

반도체 및 디스플레이 산업에서 배출되는 과불화합물은 연소, 열, 플라즈마, 촉매 등의 다양한 방법이 적용된 스크러버에 의해 분해 과정을 거친 후 배출되나, 운영 스크러버의 대부분이 과도한 에너지의 사용, 낮은 저감 효율을 보임으로써 이러한 단점의 극복이 요구된다. 압력순환흡착법과 다공성 매체 연소법의 두 가지 기술이 연계된 새로운 형태의 과불화합물 저감 스크러버를 개발하고 특성을 알아보았다. 분해 대상인 $CF_4$의 흡착비와 손실계수는 흡착 컬럼의 입구와 출구에서 농도 측정을 통해 계산하였으며, 연소기의 입구와 출구의 유량과 농도 측정을 통해 처리 효율을 계산하였다. 기존 스크러버와의 에너지 사용량 및 처리효율 비교를 위하여 다양한 유량에 대한 성능 평가가 진행되었다. 1412 ppm, 204 LPM의 $CF_4$가 유입된 흡착 컬럼에서의 흡착비는 1.65였으며, 유입되는 $CF_4$의 손실 계수는 8.2%였다. 이때 연소기로 유입되는 $CF_4$의 유량과 농도는 각각 91 LPM과 2335 ppm이었으며, $CF_4$ 19 LPM, $O_2$ 40 LPM을 사용한 연소 반응시 약 96%의 저감 효율을 나타내었다. 상용 스크러버와의 동일 운전 조건에서의 다공성 매체 연소에서의 $CF_4$ 저감 효율과 전체 에너지 사용 효율 비교시 각각 16%, 41% 이상의 저감 효율 상승과 에너지 절감 효과를 보였다.

• 한국산업보건학회지
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• 제32권1호
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• pp.53-63
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• 2022

Objectives: This study was designed to evaluate the filtration efficiency, inhalation resistance, and liquid resistance of commercial reusable masks in comparison to the performance of KF-AD masks (reference masks). Methods: Thirty-six masks were purchased from an online market. Filtration efficiency and inhalation resistance were determined in the same manner as in MFDS certification testing, respectively using TIL/IL & Filter Test 1300S (SFP Services, UK) and Breathing Resistance Analyzer DA2001 (Lambda Ray, South Korea). Results: Most of the filtration efficiencies found for the 19 masks were far lower than the test standard for KF-certified masks. Four masks met KF94 and three masks even met KF80. Most inhalation resistances were also much lower than the standard, with many almost one-half of the standard. In addition, all the masks except KF-AD masks did not pass the liquid resistance test. Conclusions: Although most of the filtration efficiency performance results found in this study for the reusable masks, which emerged as an alternative, were lower than the standard for health masks, multi-use masks can be used with a replacement filter inserted.