• The Transactions of the Korean Institute of Power Electronics
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• v.18 no.4
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• pp.403-411
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• 2013

This paper proposes an isolated bidirectional three-phase push-pull dc-dc converter for high power application such as eco-friendly vehicles, renewable energy systems, energy storage systems, and solid-state transformers. The proposed converter achieves ZVS turn-on of all switches and volume of passive components is small by an effect of three-phase interleaving. The proposed converter has identical switching pattern for both boost and buck mode, and therefore can provide seamless characteristic at the mode transition. A 3kW prototype of the proposed converter has been built and tested to verify the validity of the proposed operation.

• Journal of the Korean Society of Costume
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• v.54 no.5
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• pp.1-12
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• 2004

This Study has examined characteristics of the popular culture of the contemporary fashion show by each element as follows The fashion show place expanded its area when It moved its center because of not only the use of ordinary and public friendly place but also adjacent places post-modernism thought. The installation stage was produced by organic combination with the stage using object: The technology for the stage has produced dynamic variability and variety enough to expand the stage. The dramatic element of production technique was introduced to the fashion show to shorten gap with ordinary life and transfer a theme by facial expressions, gesture and pose. etc of a model In addition. its performance element combines other genre freely to be one time and viewers' participating type technique. At the minimalism element, clothing functions moderately as main factor of the fashion show: Technical elements are added to emphasize future Images. At sound tracks and sound effects, the show's overall atmosphere has been revived to remake various genre of music and improve images. At the fashion model, objective appearance boundary is collapsed to expand model concept and make tools of their own. The fashion show has external values of active movement of associated industry as well as economic boost enough to produce jobs, and internal values to provide aesthetic rest and satisfactions to let the ones. who are isolated from recreation values and the society, establish friendly relations with the society

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.132-134
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• 2007

하이브리드 차량 및 전기차량 구동 모터의 권선저항에 의한 손실 및 모터의 크기를 줄이기 위해 고효율, 고승압형 DC-DC 컨버터 사용이 요구된다. 기존의 부스트 컨버터는 기생저항 성분에 의해 고승압이 불가능하여 변압기를 사용하여 승압비를 향상시킨 current-fed push-pull, current-fed full bridge, dual inductor-fed 부스트 컨버터 등으로 변형되어 사용되어 왔다. dual inductor-fed 부스트 컨버터의 경우 동일조건하에서 앞서 기술된 2가지 컨버터보다 2배의 승압비를 얻을 수 있으며 1차측 전류 스트레스가 낮은 장점을 가지고 있어 대전력, 고승압 응용에 적합하다. 하지만 변압기의 누설인덕턴스에 의한 써지성 전류/전압을 제한하기 위한 부가적인 snubber회로의 사용으로 효율을 떨어뜨리게 되는 단점을 가지고 있다. 본 논문에서는 이러한 단점을 보완할 수 있는 새로운 2개의 인덕터와 1개의 변압기를 갖는 DC-DC 컨버터를 제안한다. 제안된 컨버터의 동작원리와 모드해석을 실시하고 최종적으로 400W, 42Vdc (Battery)/400Vdc (Electric Motor) 실험결과를 통해 이를 검증한다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.4
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• pp.21-28
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• 2006

In this paper, the proposed full-bridge high frequency isolated zoo voltage and zero current switching phase shifted pulse width modulation(ZVZCS PS-PWM)DC-DC converter among fuel cell generation system consist of 1.2[kW] fuel cell of Nexa Power Module, full-bridge DC-DC converter to boost the fuel cell low voltage($28{\sim}43[%]$) to 380[VDC] and a single phase full-bridge inverter is implemented to produce AC output(220[VAC], 60[Hz]). A tapped inductor filter with freewheeling diode is newly implemented in the output filter of the proposed full-bridge high frequency isolated ZVZCS PS-PWM DC-DC converter to suppress circulating current under the wide output voltage regulation range, thus to eliminate the switching and transformer turn-on/off over-short voltage or transient phenomena. Besides the efficiency of $93{\sim}97[%]$ is obtained over the wide output voltage regulation ranges and load variations.

• Archives of Plastic Surgery
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• v.45 no.2
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• pp.128-134
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• 2018

Background Non-syndromic craniosynostosis causes craniofacial asymmetry and may persist after cranioplasty. These postoperative asymmetries are primarily depressions. In some cases, patients may be subjected to pranks and harassment by their peers, affecting their psychosocial development. We propose lipoinjection enriched with adipose stem cells (ASCs) to treat the sequelae of craniosynostosis in the fronto-orbital and temporal complex in cranioplasty patients, with the goal of improving the appearance of the upper third of the face. Methods Twelve children (four boys and eight girls) between 4 and 8 years of age (mean age, 6 years) in the postoperative period after treatment for plagiocephaly, brachycephaly, and trigonocephaly were included, with a follow-up period of 1 to 18 months. Fat tissue was obtained from the lower abdomen, and ASCs were isolated using the Yoshimura technique. Lipoinjection was performed using several mini-approaches to ensure adequate distribution. Results Two different scales were used to evaluate the aesthetic outcomes. At 6 months, three plastic surgeons independent of the study classified the results using a Likert scale. The patients' parents categorized the results using a visual analog scale at 6, 9, and 18 months. R esults were favorable on both scales, as the patients' facial appearance improved and they reported increased happiness and self-esteem due to their remodeled facial appearance. Conclusions We suggest that lipoinjection enriched with ASCs is a good alternative for correcting asymmetry of the fronto-orbital and temporal contour in patients with sequelae of craniosynostosis. This treatment will help boost patients' self-esteem starting at an early age.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.61-68
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• 2004

Recently, a fuel cell is remarkable for new generation system. The fuel cell is characterized by low voltage and high current. Therefor, for connecting to general load, it needs both a step up converter and an inverter. The proposed system consists of an isolated DC-DC converter to boost the fuel cell voltage to 380[Vdc] and a PWM inverter with LC filter to convert the dc voltage to single phase 220[Vac]. Also, bi-directional DC-DC converter for fuel cell generation system is composed to improve load response characteristic. In this paper, full bridge converter and the single phase inverter are designed and installed for fuel cell. Simulation and experiment verify that fuel cell generation system could be applied for the distributed generation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.1
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• pp.59-68
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• 2009

Fuel cell generators as the distributed generation system with a few hundred watt$\sim$a few hundred kilowatt capacity, can supply the high quality electric power to user as compared with conventional large scale power plants. In this paper, PEMFC(polymer electrolyte membrane fuel cell) generator as micro-source is modelled by using PSIM simulation software and DSP based fuel cell hardware simulator based on the PSIM simulation model is implemented. The relation of fuel cell voltage and current(V-I curve) is linearized by first order function on the ohmic area in voltage-current curve of fuel cell. The implemented system is composed of a PEMFC hardware simulator, an isolated full bridge dc boost converter, and a 60[Hz] voltage source PWM inverter. The voltage-current-power(V-I-P) characteristics of the implemented fuel cell hardware simulator are verified in load variation and transient state and the 60[Hz] output voltage sinusoidal waveform of the PWM inverter is investigated under the resistance load and nonlinear diode load.

• Journal of Microbiology and Biotechnology
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• v.32 no.10
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• pp.1219-1225
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• 2022

Microorganisms involved in food fermentation not only improve the aroma and taste of the food, but also enhance its preservation. Thus, they are added as starter cultures to boost the final product quality of commercial fermented foods. Although these microorganisms originate from fermented foods and have a long history of consumption, the European Union recently applied the concept of Qualified presumption of Safety (QPS), which is a safety evaluation system for microorganisms used in food or feed in Europe. The QPS system is a species-level safety system and shares results with the European Novel Food System, a strain-level safety evaluation system. In the United States, microorganisms added to fermented foods are considered as food additives or Generally Recognized as Safe substance. In Korea, food microbe lists are presented at the species level. Moreover, the nation has established a strain-oriented evaluation system that applies temporary safety evaluation methods for food raw materials as well as new raw materials. However, when it comes to microorganisms isolated from traditional fermented foods and other fermented food products, there is no definition of the term "species," and there is a lack of an evaluation system at the species level. Therefore, such an evaluation system for microbial species used in Korean fermented foods is necessary.

• Clinical and Experimental Reproductive Medicine
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• v.50 no.3
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• pp.143-153
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• 2023

Objective: Men's sexual health plays an important role in male fertility and childbearing, as it is associated with factors such as sexual desire, healthy spermatogenesis, and erectile function. In various cultures, medicinal plants have been utilized to address male sexual issues, including infertility and erectile dysfunction. Despite recent advancements in medical science for treating male impotence, some men opt for herbal supplements as an alternative, given that numerous herbs have the potential to enhance male sexual performance. The Apiaceae family is one of the oldest plant families used for medicinal purposes. Ferula, a genus within this family, comprises approximately 170 different species worldwide. Members of this genus possess numerous therapeutic properties due to the presence of various compounds. This article aims to explore the potential impacts of Ferula plants on the male reproductive system. Methods: This review article was prepared by searching for terms including Ferula and "aphrodisiac," Ferula and "spermatogenesis," and Ferula and "male reproductive system." Relevant information was gathered through electronic databases, including ISI Web of Knowledge, PubMed, and Google Scholar. Results: The findings indicated that relatively comprehensive studies have been conducted in this area, revealing that certain Ferula species have been employed in folk medicine to boost fertility and libido. Recent research has corroborated these effects. Conclusion: It is hoped that new aphrodisiac compounds with fewer side effects can be isolated from Ferula plants in the future.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.6
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• pp.117-125
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• 2007

Recently, a fuel cell with low voltage and high current output characteristics is remarkable for new generation system. It needs both a DC-DC step-up converter and DC-AC inverter to be used in fuel cell generation system. Therefor, this paper, consists of an isolated DC-DC converter to boost the fuel cell voltage 380[VDC] and a PWM inverter with LC filter to convent the DC voltage to single-phase 220[VAC]. Expressly, The fuel cell system which it proposes DC-DC the efficient converter used PWM the phase transient control law and it depended to portion resonance ZVS switching, loss peek voltage and electric current of realization under make schedule, switching frequency anger and the switch reduction. And mind benevolence it sprouted 2 in stop circuit and it added and a direct current voltage and the electric current where the ingredient is reduced in load side ripple stable under make whom it will be able to supply. Besides the efficiency of 92[%]is obtained over the wide output voltage regulation ranges and load variations. Also, under make over together the result leads simulation and test, the propriety confirmation.