• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.185-190
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• 1996

RFSP is a computer program to do fuel management calculations for CANDU reactors. Its main function is to calculate neutron flux and power distributions using two-energy-group, three dimensional neutron diffusion theory. However, up to now the treatment has not been true two-group but actually "one-and-half groups". In other words, the previous (1.5-group) version of RFSP lumps the fast fission term into the thermal fission term. This is based on the POWDERPUFS-V Westcott convention. Also, there is no up-scattering term or bundle power over cell flux (H1 factor) for the fast group. While POWDERPUFS-V provides only 1.5 group properties, true two-group cross sections for the design and analysis of CAUDU reactors can be obtained from WIMS-AECL. To treat the full two-group properties, the previous RFSP version was modified by adding the fast fission, up-scatter terms, and H1 factor. This two-group version of RFSP is a convenient tool to accept lattice properties from any advanced lattice code (e.g. WIMS-AECL DRAGON, HELIOS...) and to apply to advanced fuel cycles. In this study, the modification to implement the true two-group treatment was performed only in the subroutines of the ＊SIMULATE module of RFSP. This module is the appropriate one to modify first, since it is used for the tracking of reactor operating histories. The modified two-group RFSP was evaluated with true two-group cross sections from WIMS-AECL. Some tests were performed to verify the modified two-group RFSP and to evaluate the effects of fast fission and up-scatter for three core conditions and four cases corresponding to each condition. The comparisons show that the two-group results are quite reasonable and serve as a verification of the modifications made to RFSP. To assess the long-term impact of the full 2-group treatment, it is necessary to simulate a long period (several months) of reactor history. It will also be necessary to implement the full two-group treatment of reactivity devices and assess the reactivity-device worths.ce worths.

• 조명전기설비학회논문지
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• 제25권11호
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• pp.113-122
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• 2011

This paper introduces and develops an efficient method for measuring power factor (PF) and its nature under nonlinear load current situations. The method is based on generating a pulse width modulated signal whose width correlates to the value of PF. This signal can then be employed as a feedback signal for controlling PF related power quantities in a system. This method has the advantages of its simple implementation, less computational complexity, and its allowable error of less than 4[%], which is justified by the computer simulation results.

• 대한의용생체공학회:의공학회지
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• 제12권4호
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• pp.309-314
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• 1991

This paper describes the results of study on the measurement method of TRMS (true root mean square value) In electrosurgical unit. We used three type (direct computing type, indirect computing type, thermal converting type) in the measurement of TRMS. Three types of measurement method were compared with respect to power level, frequencey and crest factor in addition to environmental temperature. In three of them, the thermal converting type was the best for th electrosurgical unit analyzer

• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.207-216
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• 2017

Wind energy conversion systems (WECS) which consist of wind turbines with permanent magnet synchronous generator (PMSG) and full-power converters have become widespread in the field of renewable power systems. Generally, conventional diode bridge rectifiers have used to obtain a constant DC bus voltage from output of PMSG based wind generator. In recent years, together advanced power electronics technology, Pulse Width Modulation (PWM) rectifiers have used in WECS. PWM rectifiers are used in many applications thanks to their characteristics such as high power factor and low harmonic distortion. In general, L, LC and LCL-type filter configurations are used in these rectifiers. These filter configurations are not exactly compensate current and voltage harmonics. This study proposes a hybrid passive filter configuration for PWM rectifiers instead of existing filters. The performance of hybrid passive filter was tested via MATLAB/Simulink environment under various operational conditions and was compared with LCL filter structure. In addition, neuro-fuzzy controller (NFC) was preferred to increase the performance of PWM rectifier in DC bus voltage control against disturbances because of its robust and nonlinear structure. The study demonstrates that the hybrid passive filter configuration proposed in this study successfully compensates current and voltage harmonics, and improves total harmonic distortion and true power factor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.444-445
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• 2006

The proposed site selection for transmission system construction is applied by KEPCO's regulation of the site selection criteria and it is confirmed through the deliberation of site selection committee and talking with local authority, by means of study on Present status and site survey, to verify impediment of national land use and development plan. Therefore, it is true that KEPCO has difficulty in timely completion of power facility construction because of civil appeals due to insufficiently evaluate resistance factor of stakeholder and stubborn resistance of inhabitants. This paper describes the PEES(power effect estimation system) which contributed to timely completion of transmission system construction to solve the above difficulty by utilizing IT(Information Technology) such as GIS(Geographic Information System) and LiDAR for the proposed site section. PIES evaluates project impacts on commencement of construction and finds out counter measures then makes public construction information after prediction and analysis of stakeholder's resistance factor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1432-1434
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• 2005

Single-stage converters are simpler and less expensive than convention two-stage converters. It can be a challenge, however, to design single-stage converters to satisfy certain key criteria such as input power factor, primary-side do bus voltage, and output voltage ripple. This is especially true for higher power single-stage AC/DC TTFC(Two-Transistor Forward Converter).

• 대한한의학회지
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• 제16권2호
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• pp.225-247
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• 1995

Using Bi-Digital O-Ring Test which was developed by Ohmura Toshiaki, constiution classification by the vegetables' was Measured by various muscle power measurement meters and the results are as follow: 1. Pinch Gauge (Model:pc5030HPG, Japan) is the gauge to measure finger power between the thumb and the second finger, Grip Strength Dynamometer (Model: T.K.K. 5101, Japan) is to measure the hand power (hand dynamometer), Back Strength Dynamometer (Model: T.K.K. 5102, Japan) is to measure back muscle strength, Vertical jump Meter (Model: T.K.K. 5106, Japan) is to measure the height of jump. The above gauges were and its result found that the radish, potato, carrot and cucumber can influence to muscle strength was not true. 2. When the physical constitution is distinguished by the O-Ring Test method, Taeyangin's rate appeared as average 21% although it was insisted that there will be only 0.03-0.1%. This means that the physical constitution but it appears accidently according to the examinee's emotion about the material such as vegetable etc. as favor or unfavor. 3. It was found that the result of O-Ring Test is the same at any time and at any place was not true. there is no reemergence character. 4. The import of O-Ring Test mehtod to the physical discrimination disregarded that the mental factor influences absolutely to the physical heath in the ideological physi cal constitution medical science. 5. 'O-Ring Test method is a objective judgement method.' is wrong judgement. As you see on the above result, Bi-Digital O-Ring Test set the changeable voluntary muscle as the standard of the judgument, that was first mistake logically, second in spite of leass influence of mental influence by the examiner and examinee than the vegetable discrimination influence, the test disregarded the influence. Third, only grasp of some material on hand can influence to the voluntary muscle was a wrong theory disregarding the physiology. Finally the misunderstaning his subjective view as an objective view in spite of examiner and examinee's strong influence. Therefore such kind of physical descrimination method must be sublated.

• Journal of the Optical Society of Korea
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• 제18권6호
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• pp.777-782
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• 2014

This paper proposes an RGB to RGBY color conversion algorithm for liquid crystal display (LCD) using RGW pixel structure with two-field (yellow and blue) sequential driving method. The proposed algorithm preserves the hue and saturation of the original color by maintaining the RGB ratio, and it increases the luminance. The performance of the proposed RGBY conversion algorithm is verified using the MATLAB simulation with 24 images of Kodak lossless true color image suite. The simulation results of average color difference CIEDE2000 (${\delta}E^*_{00}$) and scaling factor are 0.99 and 1.89, respectively. These results indicate that the average brightness is increased 1.89 times compared to LCD using conventional RGB pixel structure, without increasing the power consumption and degrading the image quality.

• 대한인간공학회지
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• 제35권6호
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• pp.473-492
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• 2016

Objective: This paper discusses the recent challenges to human factors engineering due to the safety culture. Background: As incidents occurring in specific fields such as logistics, plant, energy and medical sectors in Korea, as well as in the public sectors including railway, road, aviation and shipping, are recently raised as social issues from the disaster dimension, those incidents are dealt with as man-made disasters in many cases. The trend regarding all accidents as man-made disasters has been expanded in the active perspective that the controllability of all incidents should be ensured in technology development, due to change from a fatal point of view regarding disasters as random occurrence of uncertainties in the past. Method: Man-made disasters are concluded as human errors, and safety culture stands out as a cause of human errors or a new cause item recently. Because safety culture, however, is a very comprehensive term, of which true nature is obscure, although many definitions of safety culture have been presented, the safety culture may make avoid the true nature and responsibility of an incident, or make the main player and subject obscure. Raising safety culture as a cause without presenting a specific countermeasure will be just a wisdom of hindsight. Results and Conclusion: This study reviews the fundamental discussions on "Is safety culture a task of human factors engineering?" and the existing approach carried out from various perspectives in order to seek an effective approach on the new task of safety culture in the human factors engineering field. This study discusses an engineering approach to meet a precondition that safety culture is not just an added factor through a review of the approaches in the proactive fields such as nuclear power and aviation, and the traditional approaches of human factors engineering. Application: This study especially defines the perspective of socio-technological system that has expanded the existing man-machine system, and discusses a systemic approach embracing various interactions, and several overriding tasks.

• 대한전자공학회논문지TC
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• 제40권1호
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• pp.24-36
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• 2003

IMT-2000 서비스의 전송제한은 3GPP에 규정하고 있다. IS-95A 서비스보다 IMT-2000 서비스는 3배의 대역폭을 가짐으로 해서 Peak to Average가 높아졌고, 이 때문에 인접채널에 대한 영향을 줄이는 쪽으로 더 주위 깊게 설계하여야 하는 어려움이 발생하였다. 이러한 요소에 가장 민감하게 동작하는 모듈이 이동통신 시스템에 최종단에 위치하여 멀리까지 서비스를 가능케 하는 HPA(High Power Amplifier)이다. HPA는 Pl㏈ 근처에 동작시킴으로 인해 3차 5차 신호로 인해 인접채널에 영향을 미치며, 신호가 포화됨으로 인해 왜곡이 발생한다. 이에 HPA를 어떻게 선형화 시킬 수 있을 것이냐가 중요한 요소로써 작용하는데, 본 논문에서는 가장 복잡한 구조로 이루어져 있지만 선형화 방법에 있어 탁월한 개선 능력을 갖는 Feed-forward 방식을 설계 제작하였다. 본 논문은 Feed-forward의 1차 궤환부인 신호 제거 궤환부에서 얻어진 전류를 검출하여 알고리즘을 수행케 함으로써 환경변화에서도 무리 없이 동작하는 적응형 40Watt Feed-forward 선형화 증폭기가 되도록 하였다. 일반적인 RF 출력 신호를 검출하는 방식은 회로가 복잡하며, 합성기 출력에서 검출을 하기 때문에 신호검출의 정확성에서도 떨어지는 단점이 있다. 또한 선형화 증폭기의 최종 출력에서의 에러 신호를 감지하여 최적화시키는 알고리즘 역시 기존 방식인 Pilot 신호를 이용하지 않고 에러량 검출 방식을 적용하셔 W-CDMA용 선형화 증폭기가 되도록 하였다. 결과적으로 54㏈의 이득특성을 얻으면서 IW에서 40W 출력시까지 어느 동작에서도 30㎑ 대역폭 내에서 -26㏈m Max@3.515㎒ ACPR(Adjacent Channel Power Ratio) 특성, 48㏈c Max@±5㎒ ACLR (Adjacent Channel Leakage Power Ratio) 특성을 모두 만족하여 3GPP의 국제규격을 만족하는 선형화 증폭기가 되도록 하였다.