• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.9 s.114
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• pp.904-911
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• 2006

A modified energy method for the fretting wear of the steam generator tube is proposed to calculate the wear-out depth between the nuclear steam generator tube and its support. Estimation of fretting-wear damage typically requires a non-linear dynamic analysis with the information of the gap velocity and the flow density around the tube. This analysis is very complex and time consuming. The basic concept of the energy method is that the volume wear rate due to the fretting-wear phenomena Is related to work rate which is time rate of the product of normal contact force and sliding distance. The wearing motion is due to dynamic interaction between vibrating tube and its support structure, such as tube support plate and anti-vibration bar. It can be assumed that the absorbed work rate would come from turbulent flow energy around the vibrating tube. This study also numerically obtains the wear-out depth with various wear topologies. A new dissection method is applied to the multi-span tubes to represent the vibrational mode. It turns out that both the secondary side density and the normal gap velocity are important parameters for the fretting-wear phenomena of the steam generator tube.

• Korean Journal of Human Ecology
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• v.19 no.5
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• pp.873-882
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• 2010

Knitwear has become a part of fashion since aristocratic trend-setters of Medieval Spain and France began wearing luxurious silk stockings. However, in more recent times knitwear emerged as a fashion item in the early 20th century when jersey two-piece Channel dresses became popular amongst the French upper classes. Knitwear then evolved into genuine going out clothes through Sonia Rykiel in the 1970s. Sonia Rykiel has made a great contribution to developing knitwear, which she transformed from being used only in informal dresses or clothes for home wear, to a boarder in use in high-quality dresses such as those worn at parties. Unlike most designers who tend to make very different styles each year, she has restricted her clothes to those made with knitwear. The study examined the designs and formative characteristics of her knitwear in order to clarify why Sonia Rykiel's knitwear fashion is apparently so timeless. Results showed that her garments consistently used black oriented color combination, strife patterns, intarsia techniques and application of diversified subordinate materials and other materials that overcome earlier limitations of knitwear. In addition, her designs consistently express the typically Parisian sophisticated urban femininity through practicality, sensuality and playfulness. Overall, her fashion has shown that it exists for women in action through practical design within the scope of demode, the philosophy in her early days, and it has led her to hold great power over knitwear fashion for the past 40 years.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.3
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• pp.63-74
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• 2017

This study aims to contribute to the development of male incontinence underwear with an anti-aging effect that meets customer requirements by examining the types, sorts, sizes and specifications of male incontinence underwear currently sold on the market. The results of an analysis of a total of eight commercial products are as follows. 1) Among the samples, six types of incontinence underwear were of a pull-on style like regular underwear; two types were of a pad insertion style. With respect to the underwear design, four (50%) types of incontinence underwear were brief style. The rest were drawers (3, 37.5%). Only one was of a trunk (12.5%) style. 2) With respect to size, the percentage of Size 3 was 50%, followed by Size 4 (50%). Most of the size of the underwear uses hip measurement whereas Japanese products (3, 37.5 %) use waist circumference. 3) With respect to the materials of the incontinence underwear, natural fibers such as cotton were mostly used and a polyurethane or polyester was mixed to enhance the wearing sensation and stretchability of the underwear. Finally, for the structure of the pad area, a napping finish was the largest (3, 37.5%), single knit 2(25%), twill weave 2(25%), and rib weave 1.

• Journal of Environmental Health Sciences
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• v.48 no.2
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• pp.116-122
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• 2022

Background: The recent COVID-19 pandemic is one of the worst disease outbreaks of the 21th century. Due to a lack of reliable antiviral therapeutics, wearing face masks is recommended to prevent airborne infection originating from virus-contaminated bioaerosols. Objectives: The aim of this study was to evaluate the filtration efficiencies of face masks that are commercially available in South Korea for a biological aerosol of Staphylococcus aureus (S. aureus) and murine coronavirus, a well-known surrogate for human coronaviruses. Methods: We collected six different kinds of commercial masks: two Korea Filter (KF)94 (KF94-1, KF94-2) masks, one surgical (Surgical-1) mask, one anti-droplet (KF-AD-1) mask, and two dust (Dust-1, Dust-2) face masks. S. aureus (ATCC 6538), a well-performing test bacteria and murine coronavirus (ATCC VR-764) were prepared under a suitable culture condition. Then, a mask biological filtration tester was used to examine the microbial filtration efficiencies of masks. Test microorganisms were quantitatively measured via cultivation methods and microbial filtration efficiencies were calculated appropriately. Results: All face masks showed over 99.6% filtration efficiency for S. aureus or murine coronavirus. There were no significant differences among the bacterial filtration efficiencies of the face masks. KF94-1 (99.97±0.08%) and Dust-1 mask (99.97±0.07%) showed the highest (over 99.9%) filtration efficiency for murine coronavirus. KF94-1 or Dust-1 masks showed a significant virus filtration efficiency compared to Surgical-1 mask (p<0.05; Mann-Whitney U test). Conclusions: All the commercially available face masks used in this study can filter S. aureus or murine coronavirus in bioaerosols efficiently, regardless of the mask type. Therefore, our results suggest that wearing a certified face mask is a reliable means to prevent the transmission of infectious airborne diseases via biological aerosols.

• Journal of the Korean Society of Costume
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• v.63 no.8
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• pp.14-26
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• 2013

The purpose of this study is to compare and analyze Jacqueline Kennedy and Michelle Obama's fashion style from a perspective of modernism and postmodernism. The method utilized in this study was first, to examine the properties of modernism and postmodernism. Next, we explored the types of role performance of the first ladies and the application of their fashion as an aid to their roles through the precedents of the research concerning modernism and postmodernism. The results of the study are as follows. First, there was a trend of formalism and anti-formalism. Jacqueline Kennedy made her public appearances wearing a formal dress in order to express the first lady's authoritarian figure of restrained elegance. The fashion of the first lady aspired to formalism. Meanwhile, Michelle Obama followed more of a free style by eschewing the typical formality of the first lady. She created diverse styles utilizing a variety of items, which were not interrupted by form or by using heterogeneous items. Second, there is a trend of elitism and populism. While Jacqueline Kennedy preferred only haute couture designers' costume in order to show the prestige and dignity of the upper class, Michelle Obama patronized unknown designers' clothing or mid-level casual brand goods that the public favors in order to interact with the public through her fashion. Third, while modernism regards totality or unity to be important, postmodernism puts an emphasis on the eclecticism by pursuing complexity and diversity through the deconstruction of an indigenous genre. In case of Jacqueline Kennedy, this tendency featured monotone clothing color, which presented a unified full set dress that excluded decoration. Michelle Obama, in contrast, mixed and matched formal dresses and a casual cardigan or felicitously mixed luxury brand or low to middle priced brand goods.

• Fashion & Textile Research Journal
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• v.17 no.4
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• pp.646-656
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• 2015

This study investigates the conditions of Korean naval duty and combat uniforms to develop a new design. Survey participants consisted of, 723 Sailors ($25.3{\pm}6.9yr$ in age, $43{\pm}53$ months in work experience, $174{\pm}6cm$ in height, $71{\pm}9kg$ in body mass) serving in the Korean Navy for over 12 months. The questionnaire consisted of 72 questions about anthropometric characteristics, preferred design, textiles, wear mobility, and subjective perceptions. The results showed that the preferred colors for future naval duty uniforms were blue in summer (69%) and black in winter (62%). Digital camouflage pattern (60%) and darker colors on the inside of shirt collar (87%) and the edge of sleeves (84%) were preferred. They favored more than one pocket on the upper arm and chest of the shirts (58%), narrower width around pant legs and hems than the current clothing (63%), self-controlled elastic waist (55%) and no cargo type pocket on the pants (45%). There were requirements to alleviate excessive heat stress in summer and to protect from the cold and wind in winter. Wrinkle-free (85%), anti-bacterial (78%), water-proof (75%), oil-proof (90%), and elastic (67%) textiles were preferred for Korean navy uniforms. These results will be applied to develop the next generation Korean navy uniforms.

• Journal of Oral Medicine and Pain
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• v.21 no.1
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• pp.141-152
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• 1996

Oral Lichen Planus(OLP) is a idiopathic chronic inflammatory disease with more difficult to clear and higher recurrent rate than cutaneous lesions. But, there has been no estabilished theories about the proper treatment for OLP. The purpose of this study is to examine the clinical feature, relationship with systemic disease and dental treatment of OLP patients of Korea and to gain helpful information about clinical characteristics and treatment of OLP. The subjects chosen for the study were 54 patients who had visited Department of Oral Diagnosis & Oral Medicine at Yonsei University Dental Hospital Dental Hospital and diagnosed as OLP. Previous clinical records has been reviewed and questionnaires, oral examination, laboratory examination were done and recorded. The following results were obtained : 1. Of the 54 patients, 21 were men and 33 were women with an average age of 47.8 years. 2. The most common intraoral site was bilateral buccal mucosa, followed by unilateral buccal mucosa, gingiva, vesibule, lip mucosa, glossal mucosa, palatal mucosa and mouth floor. 3. The mixed, erosive and reticular form of OLP was most frequent(83.3%) clinical form. 4. OLP patients with liver disease were 5, and drug medication patients were 7. But, we could not find its evidence of association with OLP. 5. Associated events on onset of symptom were stress, denture wearing, dental treatemtn, and common cold. 6. Associated symptoms were dry mouth, tingling, sore throat, and altered taste perception. 30.8% of patients had no specific associated symptoms. 7. Aggravating factors of symptom were peppery food, hot food, fatigue, toothpaste, salty food, sour food, tension, and conversation. Reducing factors were cold food, sleeping. 69.2% of patients had no specific reducing factors. 8. There were no significant differences between normal papulation and OLP patients in CBC, SGOT< SGPT, Serum iron, Total iron binding capacity. 66.7% of subjects were positive response to fungus study for Candida Albicans. The incidence of stress and dental treatment on onset of symptom appeared high in OLP patients. Especially, high incidence of positive response to fungus study for Candida albicans, prescription of anti-fungal agents and dental treatment considerations may be helpful to treatment of OLP.

• Fashion & Textile Research Journal
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• v.16 no.3
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• pp.469-475
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• 2014

This study's goal was to obtain basic data about the functional gowns of health care providers. 828 health care providers, including 150 doctors, 224 dentists, 202 nurses, 61 physical therapists and 191 medical technicians, living in Seoul and Daejeon areas, participated in this survey. A questionnaire was created using 15 items about the current health care providers' gowns. 15 items were consisted of 3 parts; satisfaction rate and activity (part 1), preference the details of medical gown (part 2), and personal information (part 3). In this study, "wearer activity" was the main concern for them and the majority of respondents, regardless of their age and type of work, preferred the V neckline, short gown length (waist line), loose sleeves and anti-bacterial textiles. Only the doctors preferred the full sleeves, whereas, the others preferred short sleeves. The younger health care providers showed a slightly higher preference for the slim type gown, while the older providers preferred the straight type. In this study, most health care providers were not satisfied with their current gowns, except dentists. Physical therapist answered the highest score of dissatisfied for current wearing medical gown among the all health care professionals. The 20's answered the highest score of dissatisfaction among the all generation.

• Journal of Environmental Health Sciences
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• v.47 no.3
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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.

• Fashion & Textile Research Journal
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• v.25 no.2
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• pp.199-209
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• 2023

This study identified design elements of the functions required for children's ski pants. Data for this study were collected through questionnaire surveys conducted among children's ski instructors and children's sportswear developers. Five functionalities of children's skiwear were evaluated: mobility, stability, comfort, protection, and convenience. A total of 25 functional design elements related to the patterns, design details, and physical characteristics of fabrics for ski garments, were evaluated. The results of this study are as follows. First, children's sportswear developers evaluated that the pattern elements were important. Most of the pattern design elements highly related to mobility. Children's ski instructors' appraisal was that the height of the back waist was the important feature. Second, regarding the design details, children's ski instructors evaluated the size adjustment function and ventilation system as important elements. Many design detail elements were highly related in respect of stability, comfort, protection, and convenience. Third, the physical characteristics of fabric were strongly associated with mobility, comfort, and protection. As regards the physical characteristics of fabric, children's ski instructors valued anti-fouling highly, but children's sportswear developers attached more importance to the weight of the fabric. The results of this study will be useful in designing functional ski pants for children of elementary and intermediate ski levels. Since there may be limitations related to the ski level and age of children wearing ski pants, it is suggested that follow-up studies according to various groups of the ski pant wearers should be done.