• 전기학회논문지
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• 제65권1호
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• pp.40-50
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• 2016

In order to recover the power system during the wide power outage or power failure in the power plant, black start system should be properly operated without any problem. Especially power for black start in the geographically isolated areas of electric island is supplied from small emergency start-up generator, and loads are aux systems of gas turbines such as SFC(Static frequency converter). This paper introduces the international practices to overcome the voltage drop problem with harmonics of the system having the DC output such as SFC during black start in weak feed system and analyzes the relationship between house load inputs and harmonics. By varying the house load and input of power supply, this paper identified boundaries between weak feed and strong feed power. In order to verify the theory of stable condition in weak feed power system with DC output, house load is simulated using ETAP. Additionally MATLAB was used for harmonic analysis between the load inertia moment and non load inertia moment.

• The International Journal of Costume Culture
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• 제9권1호
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• pp.77-81
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• 2006

From the viewpoint of color perspective, black has more obvious effects to impart images than dress itself This study aims to examine black dress through the fashion history to highlight the aesthetic value of black and to make better use of black in designing. Black in fashion, particularly in the guise of the little black dress, became an indispensable feature of cosmpolitan style after World War I. Designers harnessed the power of black, drawn irresistibly to its innate qualities of drama and strength of line. For the past five hundred years, aside from the use of black for mourning as well as for religious, academic, legal and ceremonial dress, black with a greater or lesser dominance has been a fashion constant. Since then black has been an important color in fashion. How to use black in formative designs should be studied continuously.

• 전기학회논문지
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• 제65권12호
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• pp.2119-2126
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• 2016

In this paper, we developed a smart black box that can monitor and record the information of the sensor from subsystem in the smart grid system. The plant is the complex power system which is integrated by solar power system, grid-connected power systems, and BESS(battery energy storage system). The black box with the web-server application can connect and synchronize to an external monitoring system and a smart phone. We hope that this system is to contribute to improve operational efficiency, reliability, and stability for the smart grid power system.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.229-230
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• 2012

Platinum (Pt) has been commonly used as a counter electrode material in dye-sensitized solar cells, because it has high catalytic activity and electric conductivity as well as chemical inertness with iodide electrolyte. However, Pt is too expensive to be commercialized. Therefore, in the present study, carbon black counter electrode with Pt and carbon nano tube (CNT) was investigated. The power conversion efficiency with Pt added carbon black electrode was lower than hat of pure Pt electrode which was 6.47 %. By adding 3 wt% Pt to the carbon black counter electrode, the power conversion efficiency was maximized at 5.88 %. On them, additional adding of 1 wt % CNT, the power conversion efficiency (${\eta}$)wasincreasedupto6.21%. The reason of power conversion efficiency improvement with a proper amount of Pt and CNT was examined by comparing the impedance properties measured using EIS.

• 전기학회논문지P
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• 제67권3호
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• pp.160-167
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• 2018

In this paper, a black box, which is provided the reliability and user safety of home battery energy storage system connected with solar energy generation, is developed. In the developed scheme, a status and diagnosis data of battery management system, power conditioning system, solar energy generation and grid is measured. This status and diagnosis data is stored and displayed in the developed black box. In addition, this status and diagnosis data is stored and displayed in a monitoring system and a smart phone of user. A performance evaluation of the developed black box is carried out using emulator of home battery energy storage system connected with solar energy generation. Consequently, the developed black box is proved its superiority of the reliability and user safety.

• 한국콘텐츠학회논문지
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• 제21권1호
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• pp.210-226
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• 2021

이 글의 목적은 미국의 흑인 청년감독 라이언 쿠글러의 작품과 영화세계를 분석하는데 있다. 쿠글러 감독은 독립영화에서 출발하여 현재 할리우드에서 활동 중인 흑인 청년감독으로, 자신의 문화정체성을 바탕으로 흑인의 가치관과 내면의식을 영화로 재현하며 미국 '흑인영화'의 계보를 잇고 있는 청년감독이다. 이 글에서는 대표작 <오스카 그랜트의 어떤 하루>(2013), <크리드>(2015), <블랙 팬서>(2018)를 중심으로 그의 작품세계와 영화철학을 분석하고, 당대 미국 사회현실과의 사회맥락적 의미를 규명한다. 이 연구를 통해 쿠글러 감독은 흑인의 정체성과 흑인성(blackness)을 자기반영하는 '흑인영화'의 전통을 충실히 계승하고 있으며, 동시에 할리우드에서 내면화해 온 백인 남성가부장제 이데올로기를 전복하는 21세기 '새로운 할리우드 흑인영화 파워(New Hollywood Black Film Power)'를 상징하는 청년감독임을 확인할 수 있다.

• 한국식품영양학회지
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• 제30권1호
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• pp.175-180
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• 2017

To enhance the physiological activities and reduce the off-flavor of garlic in the Kimchi, we manufactured the Kimchi seasoning replaced with 25~75% black garlic instead of raw garlic and measured the contents of antioxidants and antioxidant activities. The polyphenol compound content was $270.91{\mu}g/mL$ in the control and $278.18{\sim}305.75{\mu}g/mL$ in the Kimchi seasoning with black garlic. The polyphenol compound content increased by increasing the amount of black garlic in the Kimchi seasoning. The polyphenol compound contents gradually decreased during storage period. The flavonoid compound content was 26.18 mg% in the control and 26.80~38.72 mg% in the Kimchi seasoning replaced with 25~75% black garlic. The flavonoid compound contents increased by increasing the amount of black garlic. The flavonoid contents were different from those of polyphenol compounds during storage periods. In the case of DPPH electron donating abilities, DPPH electron donating ability of the control was 84.82%, which showed a lower antioxidative activity than the Kimchi seasoning replaced with black garlic. The electron donating abilities of the Kimchi seasoning replaced with black garlic were increased as the amount of black garlic was increased. In the lipid peroxidation test, the control showed no lipid peroxidation during the storage period. The Kimchi seasoning replaced with black garlic also inhibited lipid peroxidation during storage as in the control. However, it showed lower activity than the control. Reducing power was higher in the Kimchi seasoning replaced with black garlic than in the control. The higher the ratio of black garlic, the higher the reducing power.

• 전기학회논문지
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• 제58권2호
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• pp.256-263
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• 2009

For the power system to keep in a stable operating state, sufficient ancillary services must be available to respond to credible contingency events and return the power system to a satisfactory operating state in the case of contingencies as well as blackout events within specified predefined limits. The logical and reasonable bases of valuing and pricing the ancillary services are required to reach the common ground among market participants. The total amount of black start service transactions is quite small compared to the total ancillary service transactions as well as energy market transactions. Black start services must be provided as one of the ancillary services in the deregulated electricity market. In order to procure and remunerate black start services, it is necessary to quantify the value of the black start sources within the power system. In this paper, an approach to assess the value of the black start service is presented based on the cost-of-service solution. Financial simulation of the influence on market participants for the proposed approach on the service is carried out. The cost of the black start service is allocated in accordance with the principle of "causer pays", and the cost is shared by the producers and consumers equally that created the requirement for the service. Under the present electricity market, the mechanism to recover the cost is not implemented, a new approach to the ancillary services to provide incentive for the service providers has to be studied in the near future.

• 센서학회지
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• 제30권4호
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• pp.267-272
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• 2021

In this study, Ag was deposited to investigate its applicability as a surface-enhanced Raman scattering substrate after forming a grass-type black silicon structure through maskless reactive ion etching. Grass-structured black silicon with heights of 2 - 7 ㎛ was formed at radio-frequency (RF) power of 150 - 170 W. The process pressure was 250 mTorr, the O₂/SF₆ gas ratio was 15/37.5, and the processing time was 10 - 20 min. When the processing time was increased by more than 20 min, the self-masking of Si_xO_yF_z did not occur, and the black silicon structure was therefore not formed. Raman response characteristics were measured based on the Ag thickness deposited on a black silicon substrate. As the Ag thickness increased, the characteristic peak intensity increased. When the Ag thickness deposited on the black silicon substrate increased from 40 to 80 nm, the Raman response intensity at a Raman wavelength of 1507 / cm increased from 8.2 × 10³ to 25 × 10³ cps. When the Ag thickness was 150 nm, the increase declined to 30 × 10³ cps and showed a saturation tendency. When the RF power increased from 150 to 170 W, the response intensity at a 1507/cm Raman wavelength slightly increased from 30 × 10³ to 33 × 10³ cps. However, when the RF power was 200 W, the Raman response intensity decreased significantly to 6.2 × 10³ cps.

• 한국광학회지
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• 제12권3호
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• pp.205-211
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• 2001

본 논문에서는 최근 주목받고 있는 장파장 EDFA(Erbium-Doped Fiber Amplifer)에서의 성능 분석, 특히 전력변환률(Power Conversion Efficiency)의 예측을 위한 밀도반전이 고정된 상태에서의 black box 모델을 유도하고 이득이 평탄화된 장파장 EDFA의 요구되는 펌프파워측면에서 수치해석과 실험을 통하여 유도된 모델의 유용성을 증명하였다. 모델을 통한 펌프파워의 예측치는 실험오차 범위내에서 1.9%이내의 정확성을 보였다. 밀도반전이 고정된 상태에서의 black box 모델은 일반적으로 980nm, 1480m, 펌핑의 경우 모두 적용이 가능하며 EDF의 3가지 이상의 길이에 대하여 입력 펌프파워와 입력/출력 신호파워의 관계를 측정하여 밀도반전이 일정한 상태에서 다른 동작점의 성능을 예측할 수 있었다. 또한 단파장 EDFA에서는 손실의 효과가 크게 나타나지 않아 해석적인 해와 일치하는 결과가 알려져 있었으나 이에 비해 장파장 EDFA에서는 여러 가지 손실의 효과가 더욱 크게 작용하게 되며 특히 paired ion의 효과로 인한 손실로써 비선형적인 관계식이 유도됨을 보였다.