• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.159-159
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• 2010

We conducted bum-in test by current stress to evaluate acceleration reliability characteristics about p-resistivity influence of GaN-based light-emitting diodes. The LEDs used in this study are the polarization field-induced LED(PF-LED) having low p-resistivity and the highly resistive LED(HR-LED) having high p-resistivity. The result of high stress experiment shows that current crowding phenomenon is occurred from the center of between p-bonding pad and n-bonding pad to either electrodes. In addition, series resistance and optical power decrease dramatically. These results means that the resistance of between p-bonding pad and p-GaN affect reliability. That's why we need to consider the ohmic contact of p-bonding pad when design the high efficiency and high reliability LEDs.

• The Research Journal of the Costume Culture
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• v.29 no.6
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• pp.763-778
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• 2021

The study aims to analyze the mixed characteristics of knit fashion design as demonstrated in Sacai's collection, which promotes hybrid and mesh-up fusion and proposes various knit design ideas. Standards for categorizing mixed phenomena of Sacai's knit design were established through a review of literature and data analysis. The study's data collection period was from 2012 to 2021, and a total of 174 items were analyzed. The following are the results. First is the fusion of traditional knit and contemporary styles expressed through de-constructive design; traditional knit styles are combined with contemporary styles through color, material, and knitting structure mixtures, such as mixing Northern European Aran, Fair Isle, Nordic, and Ropy knit. Second, the Sakai knit design combines male and female styles by mixing materials and details. A deconstructed knit cardigan was matched with androcentric pin-striped shirts worn over layered shirring skirts embellished with chiffon and lace. Third, everyday street fashion style is blended with a formal, elegant fashion style. For example, the front view has a typical everyday appearance, whereas the back view contains florid and decorated details. The style is expressed as a 360-degrees appellation, with one thing in the front and another in the back. Sacai's distinctive expressional characteristics include a mixed and de-constructive style characterized by unexpected design.

• Journal of the Korea Fashion and Costume Design Association
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• v.15 no.3
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• pp.109-118
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• 2013

Fashion icons of 21st century are not only the fashion leaders that show fashion trend but also the typical fashion signs or symbols that show visually changes in sensibility trends. The purpose of this study was to analyze the framework of 21st century fashion by the public to recognize through these changes. In this study, the background of the occurrence of various 21st century fashion icons and their characteristics were investigated and the changes of revealed features and symbolic meanings were examined compared with them of 20th century. The 24 celebrities which have been called as the bests of fashion icons since year 2000 were selected by searching the most popular search engines such as daum, yahoo and google, and 13 of them were picked as the highest in preference and awareness by surveying 50 students majoring in fashion. And then their fashion styles, backgrounds, and influence on the public fashion were studied. As a result, the 21st century fashion icons reflecting the cultural characteristics such as convergence and exaggeration and the sensitivities of fusion, collaboration, hybrid sensibility in art were powerful enough to create innovative styles destroying the era and the standard. Their styles have constantly created new looks. The exposed new individual sensitivities on media-fusion of two or more sensibility and coordination techniques without being tied to the existing anchorage system-were as influential as high fashion and leaded the imitation and reproduction by dazzling the public. As the media become more powerful, the influence of fashion icons interacted more closely with the public and has been evolved through the sensitivity of the reversal, cultural, economic, visual, or temporal fusions. To sum up, it is shown that the outstanding fashion styles suggested by the leading fashion designers have approach to the public more closely by the fashion icons.

• Journal of the Korean Vacuum Society
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• v.16 no.5
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• pp.388-396
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• 2007

KSTAR (Korea Superconducting Tokamak Advanced Research) current lead system (CLS) has a role to interconnect magnet power supply (MPS) in room temperature (300 K) and superconducting (SC) bus-line, electrically. For the first plasma experiments, it should be assembled 4 current leads (CL) on toroidal field (TF) current lead box (CLB) and 14 leads on poloidal field (PF) CLB. Two current leads, with the design currents 17.5 kA, and SC bus-lines are connected in parallel to supply 35 kA DC currents on TF magnet. Whereas, it could supply $20\;{\sim}\;26\;kA$ to each pairs of PF magnets during more than 350 s. At the cold terminals of the leads, there are joined SC bus-lines and it was constructed helium coolant control system, aside from main tokamak system, to protect heat flux through current leads and enhanced Joule heat due to supplied currents. Throughout the establishment processes, it was tested the high vacuum pumping, helium leak of the helium lines and hardwares mounted between the helium lines, flow controls for CL, and liquid nitrogen cool-down of possible parts (current leads, CL helium lines, and thermal shield helium lines for CLB), for the accomplishment of the required performances.

• Journal of the Korean Ceramic Society
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• v.54 no.1
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• pp.9-22
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• 2017

Many new functional materials have been studied for efficient production and storage of energy. Many new materials such as sodium-based and sulfide-based materials have been proposed for energy storage, but research on Li batteries is still dominant. Due to the influence of environmental concerns regarding nuclear energy, interest in and research on fusion power are steadily increasing. For the commercialization of nuclear fusion, a design standard based on a considerable level of physical analysis and modeling is proposed. Nevertheless, limitations of existing materials in nuclear fusion environments limit practical applications. Tritium propagation material for continuous fusion reaction is one of the core materials, and therefore research on this material is being carried out intermittently. The key material for Li-based energy storage and tritium generation is the functional material Li-M-O. In this review, a structural description of functional Li-M-O system materials and technical trends for its applications are introduced.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.229-232
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• 2006

The Center for Technology Fusion in Construction was established on Sep. 30, 2005, with the support of Korea Ministry of Construction and Transportation and Korea Institute of Construction and Transportation Technology Evaluation and Planning. It aims to develop the next generation of economic growth engine through the fusion of traditional construction technology and cutting-edge emerging technologies. To achieve this vision, the center tries to establish a system for the systematic construction research based on the fusion approach. The scope of the center focuses on improving the performance of construction project, including planning, design, construction, and maintenance. Along with the newly developed Korea Construction Technology Road Map, the center is expected to significantly contribute to the development of innovative construction technologies for the world-class Korean society.

• Bulletin of the Korean Chemical Society
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• v.27 no.2
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• pp.281-285
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• 2006

Microbial fuel cells (MFC) stacked with bipolar plates have been constructed and their performance was tested. In this design, single fuel cell unit was connected in series by bipolar plates where an anode and a cathode were made in one graphite block. Two types of bipolar plate stacked MFCs were constructed. Both utilized the same glucose oxidation reaction catalyzed by Gram negative bacteria, Proteus vulgaris as a biocatalyst in an anodic compartment, but two different cathodic reactions were employed: One with ferricyanide reduction and the other with oxygen reduction reactions. In both cases, the total voltage was the mathematical sum of individual fuel cells and no degradation in performance was found. Electricity from these MFCs was stored in a supercapacitor to drive external loads such as a motor and electric bulb.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.582-582
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• 2012

Characteristics of a fusion-driven transmutation reactor was investigated. A compact reactor concept is desirable from an economic viewpoint. For the optimal design of a reactor, a radial build of reactor components has to be determined by considering the plasma physics and engineering constraints which inter-relate various reactor components. In a transmutation reactor, design of blanket and shield play a key role in determining the size of a reactor; the blanket should produce enough tritium for tritium self-sufficiency, the transmutation rate of waste has to be maximized, and the shield should provide sufficient protection for the superconducting toroidal field (TF) coil. To determine the radial build of the blanket and the shield, not only a radiation transport analysis but also a burnup calculation were coupled with the system analysis and it allowed the self-consistent determination of the design parameters of a transmutation reactor.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2016.11a
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• pp.199-200
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• 2016

전 세계적으로 효율이 높은 LED 조명이 각광 받기 시작하면서 기존의 조명보다 에너지 효율이 높은 LED 조명을 보다 효율적으로 사용하기 위한 다양한 방법들에 대한 관심이 높아지고 있다. 이에 본 논문에서는 기존의 스위치 구조의 제품을 분석하여 한계점을 파악하고, 사용자가 스위치를 교체하는 단순한 방식으로도 스마트 조명을 경험 할 수 있도록 LED조명을 효율적으로 사용하기 위한 벽면형 스위치 구조를 디자인 하고자한다.

• KIEE International Transactions on Power Engineering
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• v.3A no.2
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• pp.100-108
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• 2003

This paper presents the design and performance results of a pair of 6-kA high-temperature superconducting (HTS)-copper current leads, in which, over a short length at the warm end (e.g.,77K) of each HTS section, comprised of paralleled Bi-2223/Ag-Au tapes, is operated in the current-sharing mode. Because of their reliance on vapor cooling, the leads are applicable only to liquid helium cooled superconducting magnets such as those used in high-energy Physics accelerators and fusion machines. The experimental measurements have demonstrated that key performance data of the new 6-kA HTS-Copper leads agree reasonably well with those expected from design.