• 한국응용과학기술학회지
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• 제35권3호
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• pp.702-708
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• 2018

하이드로겔은 다량의 물과 화장품용 성분들을 함유할 수 있는 천연고분자 구조를 가지고 있으며 내부의 친수성기들이 활성성분을 다량 함유하고 효과적으로 전달할 수 있는 구조체를 형성할 수 있어 화장품 소재로 즐겨 사용되고 있다. 화장품용 하이드로겔에 첨가하는 소재로 셀룰로오스가 많이 이용되고 있는데 파우더 형태의 셀룰로오스와 면섬유 및 셀룰라아제를 처리한 면섬유와 같이 다양한 형태의 셀룰로오스를 하이드로겔에 적용했을 경우 하이드로겔의 물성변화 및 외관변화를 조사해 보았다. 일반적으로 사용되는 셀룰로오스 파우더를 하이드로겔에 첨가하였을 경우 예상과 달리 하이드로겔의 인장강도가 상당히 저하되는 결과를 보였다. 첨가하지 않았을 때 대비 0.1%와 0.3%의 셀룰로오스 파우더를 첨가한 시료는 각각 10%, 14%의 인장강도 저하현상을 보였다. 이와는 다르게 면섬유를 0.1 ~ 0.3% 첨가하였을 경우 하이드로겔의 강도가 약 20% 증가함을 보였다. 그러나 길이가 긴 면섬유는 뻣뻣하여 하이드로겔에 혼합시 분산성에 문제를 보였다. 이를 해결하기 위하여 면에 셀룰라아제를 처리함으로써 효소-분해 반응을 통해 섬유의 유연성을 증가시킬 수 있었다. 또한 효소 처리된 면섬유를 하이드로겔에 첨가하여 보습성의 변화를 조사한 결과 셀룰라아제를 처리한 면섬유를 함유한 하이드로겔은 처리하지 않은 면섬유-하이드로겔 대비 380% 증가된 보습성을 보였으며 또한 혼합 가공시 우수한 분산성을 보였다.

• 대한의생명과학회지
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• 제28권4호
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• pp.317-321
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• 2022

Due to COVID-19 pandemic, wearing face masks is obligatory to prevent respiratory virus transmissions in the community. However, there are few studies of the desirable number of wearing a face mask, and how to store them for reuse. Therefore, in this study, a survey was conducted among 208 healthy adults, and 27 kf-94 masks worn for 1, 2, and 3 days were collected. To estimate the risk of bacterial contamination, we analyzed the extent of bacterial contamination of the BHI medium and 16S rRNA gene sequencing. With an increase in the number of days of using the mask, the degree of bacterial contamination of the used mask gradually increased. As a result of 16S rRNA PCR performed for strain identification, Staphylococcus, known as a pathogenic bacterium, was identified the most. In conclusion, we found that wearing a cotton KF mask provides an optimal environment for microbes, which are related to the skin and respiratory system, to thrive. Therefore, it is also important to reduce the risk of bacterial infection of the face mask with appropriate sterilization methods.

• 한국응용과학기술학회지
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• 제33권1호
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• pp.30-40
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• 2016

본 연구는 2단계 발효된 달팽이 추출물을 5% 사용한 시트 마스크 팩 (2F-SEM)을 개발하였다. 이에 대한 피부미용학적 연구를 수행하기 위하여 순면 100%의 시트를 사용하여 얼굴모양으로 커팅하여 사용하였다. 플라세보 마스크 팩 (placebo mask pack; PM)과 일반 용매추출에 의한 달팽이 추출물을 사용한 마스크 팩 (Gene-SEM)에 대하여 피부 개선효과를 측정한 결과를 보고한다. 첫째; 2F-SEM의 보습효과는 PM 보다 11%, Gene-SEM는 PM 보다 4.7%가 상승되었다. 둘째; 2차 발효달팽이 추출물이 함유된 마스크 팩의 탄력도는 PM 보다 13.8%, Gene-SEM PM 보다 6.7% 이상 개선하는 효과를 보였다. 셋째; 2F-SEM의 피부 거칠기는 PM 보다 6.80%, Gene-SEM는 PM 보다 2.3%가 개선되었다. 넷째; 2F-SEM의 멜라닌감소효과는 PM 보다 15.0%, Gene-SEM는 PM 보다 8.7%이상 개선되었다. 다섯째; 2F-SEM의 잔주름개선효과는 PM보다 8.0%정도 우수하였다. Gene-SEM는 PM 보다 5.1%이상 개선되었다. 여섯째; 2차 발효 물을 이용한 2F-SEM의 관능 평가는 부드러움(softness), 보습 감(moisture), 주름개선효과(fine wrinkle improvement)에서 유의 차 있는 사용감촉을 보였다.

• 한국컴퓨터정보학회논문지
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• 제27권2호
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• pp.179-185
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• 2022

연구의 목적은 신종 코로나바이러스 감염증(코로나-19) 예방을 위한 마스크 사용에 따른 마스크 속 구강건강의 부정적 요인과 구강건강관리의 중요성에 대한 기초자료를 제공하고자 한다. 2021년 5월 3일부터 31일까지 전국에 있는 20~59세의 성인 232명을 대상으로 설문조사 후 통계분석 하였다. 마스크 선택은 남자 63.9%, 여자 61.3%로 남녀 모두 KF_94 마스크를 높게 선택하였으며 연령이 높을수록 KF_94 마스크를 선택하는 것으로 나타났다. 마스크 착용에 의한 자가 구강건조감과 구취에 대한 인식은 면 마스크 착용하는 군에서 구강건조를 높게 느끼는 것으로 나타났으며 통계적으로 유의한 차이가 있었다. 마스크 종류는 구강건조감(r=.142, p<.05), 연령(r=.234, p<.01)과 유의한 정적 상관관계가 있었다. 마스크 착용시간은 연령(r=.158, p<.05)과 유의한 정적 상관관계가 있었고, 직업에 따라서는 부적상관관계로 나타났으며 통계적으로 유의하였다(r=-.472, p<.01). 구강건조감은 구취(r=3.04, p<.01), 연령(r=.224, p<.01)과 통계적으로 유의한 정적상관관계를 보였다.

• 한국환경보건학회지
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• 제47권3호
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• pp.292-301
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• 2021

Objectives: Wearing medical masks has been recommended since the declaration of coronavirus disease-19 (COVID-19) as a pandemic disease. Certified medical masks are evaluated according to filtration efficiency and facial inhalation resistance. However, some people use non-certified common masks. This study aimed to evaluate various non-certified commercial masks based on the certification criteria for medical masks. Methods: Twenty mask products (three anti-droplet, three disposable dental, eight fashion, three cotton, and three children's masks) were selected. For performance evaluation, filtration efficiency and facial inhalation resistance tests were conducted. The evaluation method followed the certification method for KF-certified masks of the Ministry of Food and Drug Safety (MFDS) and the N95 respirator of the National Institute for Occupational Safety and Health (NIOSH). Results: None of the 20 masks met the KF94 certification standard set by the MFDS. Four and three masks respectively met the KF80 certification standard and the N95 standard of NIOSH. Filtration efficiency was significantly higher in three-layer masks than in single layer masks. Pleated-type masks had higher filtration efficiency than cone-type masks. There was no correlation between the structure of masks and facial inhalation resistance. Conclusion: While no masks complied with the KF94 certification standard, a few masks met the KF80 and the N95 certification standards of NIOSH. Although some people wear non-certified commercial masks, protection from aerosols is not guaranteed by such masks. Evaluation of the protection efficiency of non-certified mask against microbiological infection is needed for the prevention of infectious disease.

• 한국의류학회지
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• 제34권2호
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• pp.291-302
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• 2010

This study details the actual wearing conditions and favored design of ready-made pants for obese women, particularly for those in their twenties and thirties. The actual problems that customers feel and the preferred design of pants were suggested based on the survey and from the standpoint of consumers. The findings of the survey are as follows. The actual wearing conditions in the survey, 80.5% like wearing pants. The main reason to prefer pants is that pants are more convenient for social or professional work activities. The main reason to avoid wearing pants is that the pants (in general) do not mask an obese body shape. The most favored was Denim/Elastic and the second most favored was Cotton/Elastic from the survey. On average, elastic materials are preferred over non-elastic materials. The reason was the comfort in wearing and convenience in social or professional activities that could mask obesity. In terms of the style, the most favored was blue jeans and the second favored was semi-formal. A straight-silhouette is the most favored as it was able to help mask obesity. The most favored position for the waistline is 4 cm lower than the natural waistline. The most favored pant length is where the pants slightly touch the floor when they stand with shoes on. For obese women the pants development that covers the weak points of the body shape giving, which is comfortable and active are desired.

• Journal of Medicine and Life Science
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• 제16권1호
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• pp.23-26
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• 2019

Total scalp irradiation is a challenging treatment because of unique concave target volume and difficulty with bolus applying. There are few reports about bolus applying methods to the entire scalp in detail. Application of conventional bolus (wax or superflab) is widely used, and it is considered effective. However, the curvature and irregularity of the scalp can produce significant air gap, resulting in inadequate radiation dose distribution. We describe a new method to applying the bolus to the entire scalp. We sutured 1 cm thickness superflab bolus on the thermoplastic mask using cotton string. This method can reduce the air gap between the bolus and scalp and be reproducible.

• 대한치과기공학회지
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• 제33권1호
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• pp.93-102
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• 2011

Purpose: The study aimed to evaluate working environment for dental technician by measuring dust level, ventilation conditions and the use of personal protective equipment and to provide basic information required to improve working environment and develop health education programs for dental technician. Methods: A total of 240 dental technician who are registered with the Daegu Association of Dental technician and working at 34 dental laboratories participated in the study. And the dust level was measured at 21 different spots in 16 dental laboratories out of 34. Results: Of 34 dental laboratories, 31 (91.2%) were equipped with a ventilator, but the remaining 3 (8.8%) did not have a ventilator. By the number of ventilator, 1 to 3 ventilators were found in 22 dental laboratories (71.0%), 4 to 6 ventilators were in 7 laboratories (22.5%) and more than 7 ventilators in 2 laboratories(6.5%). According to the frequence of changing filters in dust collector, 20 dental laboratories (58.9%) changed filters every four weeks, 10 laboratories (29.4%) changed them every six weeks and 4 laboratories (11.7%) changed them every eight weeks. Of total respondents, 114 (61.3%) said they wore a mask all the time while working, 56 (29.6%) said they frequently wore a mask, 19 (10.1%) said they did not wear a mask. As for the type of masks, 159 (84.1%) used a disposable mask, 25 (13.2%) used a cotton mask and 5 (2.7%) used an anti-dust mask. For dust sat on their outfits while working, 102 (54.0%) shook their uniforms inside workplace to keep dust off the uniforms, 64 (33.9%) did not anything until they wash their uniforms and 23 (12.1%) shook their uniforms outside workplace to keep dust off the uniforms. Of total respondents, 182 (96.3%) had a particle in their eyes while carrying out grinding work. Based on the measurement of floating dust at workplace, 3 dental laboratories showed dust concentration exceeding the minimum level of 10 mg/$m^3$ allowed under the permit for environment. Of those, 1 laboratory had the dust concentration that was more than 1.5 times higher than the minimum level. Dust concentration was higher in laboratories that used a dust collector with 0.5 horse power and changed filters more than 3 weeks ago. Dust comprised of nickel (more than 70%), chrome (9%) and others. The mean chrome concentration was more than twice higher than the minimum permissible level of 0.5 mg/$m^3$. There were two laboratories that showed chrome concentration exceeding the level of 0.4 mg/$m^3$. Like dust concentration, chrome level was higher in laboratories that used a dust collector with 0.5 horse power and changed filters more than 3 weeks ago. There were six laboratories that had nickel concentration exceeding the minimum permissible level of 1 mg/$m^3$. Of those, one laboratory had nickel concentration that was more than three times higher than the minimum permissible level. Nickel concentration was also higher in laboratories that used a dust collector with 0.5 horse power and changed filters more than 3 weeks ago. Conclusion: It is not likely that heavy metal concentrations found in the study constitute respiratory dust. It is however necessary for health of dental technician to apply the Industrial Safety and Healthy Law to dental laboratories and make recommendations for the use of personal protective equipment, installation of a proper number of ventilators, more frequent change of filters in dust collector and improved ventilation for polishing work. At the same time, dental technician need education on how to use personal protective equipment and how to efficiently remove dust from their uniforms.

• 복식
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• 제53권1호
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• pp.1-15
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• 2003

This study as one of a series of systematic studies about dancing costumes will compare the costumes of the middle age with their normal style of dress. In brief, this study wants people to know about middle a9e dancing costumes and understand the culture in the middle ages. It was found that people's everyday clothes in the middle age such as Surcot. Surcot-ouvert, Pourpoint, Houppelande were used as dancing costumes. They were, however. changed from the public's clothes which were tight and long. Rather than wearing costume over others. dancers wore costumes which had slits on skirt or sleeves to increase motion. With the Wild Man of the Wood's which only nobles used for their dancing costumes. costumers highlighted the beauty of human body There were various costume materials used in the middle ages like silk. cotton fabrics, linen or brocade. These materials were used for Surcot and Pourpoint as dancing costumes. The naturalness of nature or geometric patterns also was expressed on the costumes. Further about those patterns, because the development of stained glass, vivid colors were used especially red, light green, blue etc. As for the hair styles used, dancers let their hair down and put a jeweled crown over their hair. In summation. dancers wore the same clothes that normal People did, but the costumes were different depending on social status and gender. The costumes of ordinary people's were based upon ordinary clothes that moved and emphasized the dynamic motion. On the other side, the court dancers' costumes were very fancy. symbolizing a measurement of nobles' from wealth and authority. as well as an expression of a sense of beauty, The main features of middle ages follows. : To emphasize vitality, there were long slits on the side of skirt. Hair decorations and jewels are more used than in the ancient age's. To hide a dancer's social status. they could use a mask. Wild Man of the Wood's was used for the body makeup. All these features of the dancing costumes must contribute to the progress of the dance in the middle age's.