• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.20-21
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• 2016

In this study, the shielding properties of concrete with conductive materials as shielding material for electromagne- tic pulse(EMP) within 10kHz~18GHz were investigated. The shielding effectiveness of specimens were compared with different entrained materials. The shielding effectiveness were determined according to MIL-STD-188-125-1, IEEE-STD-299 at 28 days of concrete curing. The results of shielding effectiveness did not meet the criteria(80dB) severely.

• Journal of the Korean Society of Clothing and Textiles
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• v.1 no.2
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• pp.89-94
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• 1977

This is a study of the history and the changes of methods of making shroud from Koryo up to present. Korea is Known as a country of East with its courtious people, and naturally the people observed the proprieties, especially on the funeral, in performing religious services and worshiping of the ancestors. Since Koryo and Yi Dynasty, because of the complexcity of the formalities under the confucianism, the shroud also became very complex. The process of making shroud was various according to the classes and economical circumstances. They made shroud of fine textured hemp cloth or silk, selecting one of 'good days' in leap year. As they believed the shroud should be rotten as soon as possible, fine textured hemp cloth was common as for the material. The color of the shroud was either plain or colored as the casual wears. In sewing shroud, the thread shouldn't be knotted nor connected in each seam and the strips should not be even numbered. These methods of making shroud have been changed variously and symplified according to the economical circumstances up to now.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.255-257
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• 2018

본 논문은 리튬폴리머 배터리를 입력 전압원으로 High-Altitude Electomagnetic Pulse (HEMP) 구동용 고밀도 고전압 충전기의 설계를 다루며, 제안하는 충전기는 독특한 3상 델타-와이 변압기 구조를 갖는 5.4kW 용량의 LCC 공진 컨버터로 제작 되었다. 풀브릿지 형태로 4개의 스위치를 사용하는 단상 충전기는 동일 용량을 설계하는 경우, 입력 전류량이 높아 소자의 발열로 충전기의 동작 시간이 제한되고 누설 인덕턴스에 의한 스파이크성 전압이 크게 발생하여 충전기의 안정적인 구동이 어려운 문제점이 있다. 이를 해결하기 위해 6개의 스위치를 사용하는 삼상 충전기를 HEMP 구동용 고밀도 고전압 충전기에 적용하였다. 동일 용량의 단상과 삼상 충전기 설계과정과 시뮬레이션 결과를 분석해 각 충전기의 차이점을 비교하고, 저항 및 커패시터 부하 실험으로 제안하는 삼상 충전기의 동작과 성능을 검증하였다.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1121-1128
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• 2011

The HEMP has very short rising time with several tens of kV/m, and very dangerous to almost of the electronics. And the certain level of EMP shielding effectiveness is necessary for mos t of the systems andequipment. In EMP shielding effectiveness, the peak value and the rising time in the system are the most considerable parameters. In order to find out these parameters, we need to estimate the pulse shape in time domain. In this paper, we propose the methods to estimate the penetrated pulse in time domain using measured shielding effectiveness and digital filter modeling technique. The validity of the Digital filter modeling technique is verified by the HFSS.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.482-484
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• 2006

대마에 대한 분석 결과, 인피 섬유의 경우 리그닌 함량은 7.6%로 다른 목질계 바이오매스나 일년생 초본류와 비교하여 매우 낮은 리그닌 함량을 나타냈으며 탄수화물 함량은 65.4%로 목질계 바이오매스와 유사하고, 초본류보다는 오히려 높았다. 목부는 리그닌 및 탄수화물 함량이 활엽수와 유사한 경향을 나타내었는데 특히 높은 자일란의 함량이 확인되었다. 또한 회분 함량이 인피섬유와 목부에서 각각 5.0%와 2.3%로 낮은 값을 나타내어 당화 및 발효 공정에 적용될 때 회분에 의한 공정 장애(스케일링 등)의 가능성을 낮추어 줄 것으로 사료되었다. 최종적으로 이러한 화학적 분석을 통해 대체에너지 생산을 위한 자원으로서 대마의 가능성을 확인할 수 있었다.

• Journal of Fashion Business
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• v.13 no.3
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• pp.86-98
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• 2009

The fashion industry saw the emergence of environment-friendly and natural fabric materials recently. The naturalism trend has established sectors in the textile and fashion industry also. Ramie and hemp have long been favored fabric materials in Korea especially for summer. The hand-related mechanical/physical properties of the fabric specimens were analyzed using a fabric objective measurement system, KES(Kawabata Evaluation System). Subjective evaluation was also implemented based on a series of selected adjectives. Studies on natural dyeing methods are important since the establishment of scientific approach is needed in terms of environment and human safety along with the reproduction of traditional natural dyeing methods. In this study, linen, ramie, hemp, and cotton/polyester/linen union fabric specimens were used for the natural dyeing using Rubia akane Nakai with the mordant of gallnut. ${\Delta}E$ values of dyed fabric specimens, mordanted and dyed once using Rubia akane Nakai, increased significantly compared to those of repeatedly dyed fabric specimens without mordanting.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2001.04a
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• pp.63-66
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• 2001

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.6
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• pp.415-423
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• 2018

We herein investigate the E1 pulse for evaluating the conducted performance of transmission lines connected to the electromagnetic pulse protection facilities against a conducted high-altitude electromagnetic pulse threat exposed to an external electromagnetic environment. The existing E1 pulse generator uses the Marx generator high-voltage step-up method; however, in this research, we used the Tesla transformer method to easily change the broadband output voltage(30 to 350 kV). We also analyzed the controller, power supply, high-voltage booster, and pulse-shaping device. The E1 pulse performance using the Tesla transformer was predicted through simulations and validated by measurements.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.4-12
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• 2002

It is well-known method to use Ethylene Oxide (ETO) as a fumigant to preserve cultural heritage from the attack of some bacteria and insects. In this article, we investigated co]or change of some cultural material upon treating ETO. The cultural material was selected from Korean paper (hanji), ancient books, blue prints, pigments (DA, DB, DC, DD, DE and DF). hemp cloths, and colored pictures (DG, DH, Dl, DJ, DK). The $\Delta$E value in chromaticity coordinates for each item was obtained upon treatment with ETO at concentration of 200, 250, 380, 500, 710 g/m$^3$ respectively. The $\Delta$E value was derived from the equation of L*at with the data checked 24 hr, 48 hr, and 72 hrs respectively. The Korean papers(hanji) showed slightly change in color by $\Delta$E 0.8. In the case of ancient books, it showed $\Delta$E 2.91 which was easily distinguishable with the naked eyes. For the almost 73％ of blue prints, the value of $\Delta$E was as much as more than 4.0 that it is recommended not to use. In the case of pigments, the value of $\Delta$E was ranged from 0.15 up to 4.0 so that it should be very careful before use. The hemp cloth dyed with natural indigo showed less than 1.00 in $\Delta$E, while various colored hemp cloth showed wide range of $\Delta$E from 1.00 to 4.00. Finally, from the fact that the color change was as small as less than 1.00 for the colored pictures, it is thought that treatment with ETO is one of method to be used to this purpose.

• Journal of the Korean Society of Costume
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• v.52 no.6
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• pp.25-39
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• 2002

The purpose of this study is to look into dressing practices at the Woinarodo region in terms of ordinary and ritual clothes. Men wore Bqji(trousers) and Jeokori(jackets) as their plain clothes and sometimes Jangsam mid Durumaki(topcoat). During the period of Japanese colony, men wore Western-style clothes. For women it was basic to wear Chima(skirts) and Jeokori. And they preferred Momppe rather when in Japanese rule. In arrangements for their head, men put on gut, and had their hair cut during Japanese nile. Women laid a bundle of their braided hairs on the head or braided their hair, while married women did their hair up in a chignon during the ruling period People of the region put on straw and leather shoes, and then rubber ones since the late 1930s. Hand weaving was a major means of living for women at the region. Ramie, hemp and cotton were mainly weaved by hand. Starching was applied mainly to ramie and cotton. Glues for starching were made of raw rices, cooked rices, wheat flour or gloiopeltis tenax. For ritual clothes, especially in wedding, bridegrooms arranged themselves with Samokwandae and then Put on Baji, Jeokori, Durumaki and Danryung. But they Put on Western-style dresses as the liners of Danryung, and wear Nambawi Rather than the Samo after korean independence from Japanese rule. Bridges wore Chima, Jeokori and Wonsam and Chokdoori and covered their face with Hansam Wonsam did not be worn any longer after Korean independence from the rule. Shrouds for funeral ceremony were manufactured with silks, cotton and hemp, when the chief mourner wore hempen hoods and funeral robes, while women, Chima, made of hemp. and any type of Jeokori.