• Bulletin of the Korean Chemical Society
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• 제28권7호
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• pp.1151-1155
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• 2007

In a previous study, a catalyst (A) was discovered for oxidative decarboxylation of melanin-concentrating hormone (MCH). To explain the catalytic action and to predict the structure of a new catalyst with improved activity, docking simulations were carried out for the complex formed between A and MCH. The simulations suggested that the three terminal groups of A form a hydrophobic pocket and that van der Waals interactions between the hydrophobic pocket and MCH play a role in stabilizing the MCH-A complex. Consequently, a new catalyst (B) was designed and synthesized in expectation of improved catalytic activity resulting from enhanced van der Waals interactions. The new catalyst, however, showed slightly lower catalytic activity. Lack of the accurate solution structure of MCH may be one of the factors associated with difficulties in prediction of improvement in catalytic activity by purely theoretical means. The results, however, revealed that variation of the acyl portion of the hydroxyproline portion may lead to improved catalysts.

• 한국정밀공학회지
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• 제30권12호
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• pp.1327-1333
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• 2013

Air bearings are widely used in precision stages because of low friction and high motion accuracy, however, they suffer from low stiffness in comparison with rolling bearings or hydrostatic bearings. So, several preloading methods using weight, magnet and vacuum force, and opposing pads have been used to increase the stiffness of the air bearings. In this paper, pressure distributions of the vacuum preloaded porous air bearings are calculated using the proposed method. And then, the load capacity and stiffness are analyzed. For the vacuum preloaded air bearings, the stiffness is increased owing to reduced bearing clearance by vacuum force. The simulation results indicate that variation of vacuum pressure with clearance in the vacuum pocket gives rise to low stiffness, so the vacuum pocket should be designed for pressure to be constantly maintained regardless of the bearing clearance by means of large effective pumping speed.

• 한국해양공학회지
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• 제23권1호
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• pp.67-73
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• 2009

This study presents the results of a slamming experiment using a pneumatic cylinder. The employment of the pneumatic cylinder showed a relatively good repeatability when the results were compared with those of other slamming devices. The experiment was done for various incident angles. An air pocket was believed to cause a reduction in the magnitude of the impact pressure with an incident angle of $0^{\circ}$ for the water entry. A high speed camera was used in an attempt to locate the time of the contact between the bottom of the specimen and the free surface. It seemed that the maximum pressure occurred before the water contacted the bottom of the specimen.

• Journal of Periodontal and Implant Science
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• 제27권2호
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• pp.305-315
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• 1997

The purpose of this study was to investigate the effects of smoking on adult periodontitis after non-surgical periodontal therapy. The study population consisted of 40 patients with moderate to advanced periodontitis. Smokers(n=20) were defined as individuals smoking at least twenty cigarettes per day at the time of the initial examination. The non-smoking group(n=20) consisted of individuals who were not smoking at the initial examination. The average age was 42.4 years for the smoking and non-smoking group. Examination regarding plaque index, gingival index, pocket depth and contrast phase microscope were performed. Evaluation were made at the first, the second and the fourth weeks after periodontal non-surgical therapy. The results were as follows: 1. Clinical indices including plaque index, gingival index, and pocket depth were decreased in both smoking and non-smoking group at the first, the second, and the fourth weeks. Especially, clinical indices of non-smokers were more significantly decreased than those of smokers. 2. Non-motile rods were increased and motile rods were reduced at the fourth week. spirochetes were reduced significantly in the non-smoking group at the fourth week. These results suggest that smoking play a minor role in adult periodontitis after non-surgical periodontal therapy.

• 한국의류산업학회지
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• 제3권3호
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• pp.249-256
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• 2001

This study was to investigate difference across socioeconomic groups in factors of purchase intention of apparel in internet shopping mall and in satisfaction were internet shopping mall. A questionnaire was administered to collage students majoring in fashion design during May of 2001. Data was analyzed by using Factor analysis, T-test, one-way ANOVA, Duncan test, ${\chi}^2$-test. Factor analysis yield three factors of purchase intention, purchase stimulus, convenience and economic and rationality. Significant differences were found across levels of monthly pocket money and types of payment for purchase apparel of internet shopping mall purchase stimulus (factor 1). In convenience and economics (factor 2), differences were also significant across levels of purchase frequency, product price and payment ways of internet sopping mall. Significant difference was identified across sex type and levels of product price purchased in internet shopping mall (factor 3). Regarding internet shopping mall satisfaction, differences were significant across levels monthly pocket money and apparel purchase frequency of in internet shopping mall.

• 한국해양공학회지
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• 제23권4호
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• pp.12-18
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• 2009

The present study focused on the compressibility of partially filled fluids in a sloshing tank. Filling ratios ranging from 18% to 26% were used to find compressible impact on a vertical wall. The model test was for 1/25 scale of a 138 K LNGC cargo tank. To investigate the two dimensional phenomenon of sloshing, a longitudinal slice model was tested. A high speed camera was used to capture the flow field, as well as the air pocket deformation. The pressure time history synchronized with the video images revealed the entire compressible process. Three typical impact phenomena were observed: hydraulic jump, flip through, and plunging breaker. In particular, the pressure time history and flow pattern details for flip through and plunging breaker are presented.

• 한국의류학회지
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• 제29권11호
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• pp.1498-1506
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• 2005

This study intended to identify the effects of consumer ethnocentrism and fashion leadership on purchasing attitude toward luxury brands. This study also identified differences in consumer ethnocentrism and fashion leadership according to demographic characteristics and the relationship between ethnocentrism and fashion leadership. The data used in this study were gathered through surveying university students living in Seoul using convenient sampling method, and 325 questionnaires were used in t test, F test, and regression analysis. The results showed significant differences in consumer ethnocentrism according to age, clothing expenditure, monthly pocket money and in fashion leadership according to age, major, clothing expenditure, monthly pocket money, and monthly household income. There was no significant relationship between consumer ethnocentrism and fashion leadership. Consumer ethnocentrism negatively influenced the purchasing attitude whereas fashion leadership influenced positively. The results of this study provide insights into young consumers' increasing demands toward luxury brands and suggest some promotional tools that might prove effective.

• 한국융합학회논문지
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• 제9권4호
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• pp.303-311
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• 2018

장애인과 보호자와의 관계 유형에 따른 장애인의 구강건강상태의 관련성을 알아보고자 장애인 보호자에게 장애인과 보호자의 응집력과 의사소통과정을 자기기입식으로 설문 조사하였고, 장애인의 구강건강상태는 DMFT index, 제1대구치 건강도, Pocket depth로 평가표를 작성하여 총 78부를 분석하였다. 통계프로그램은 SPSS win. 24.0을 이용하였으며 유의수준은 .05에서 검증하였다. 장애인과 보호자와의 관계 유형에 따른 장애인과 보호자의 응집력(p<.01), 의사소통과정(p<.01)에서 유의한 결과를 보였다. 장애인의 구강건강상태에서는 DMFT index(p<.01), 제1대구치 건강도(p<.01), Pocket depth(p<.01)에서 유의한 결과를 보였다. 따라서 장애인에게 어머니는 응집력, 의사소통과정, 구강건강상태 등 대부분의 항목에서 긍정적인 영향을 미치는 것으로 나타났다. 반면 장애인과의 응집력, 의사소통과정 등에서 낮은 영향을 미친 활동보조인력과 장애인의 구강건강상태에 낮은 영향을 미친 배우자에게는 장애인과 보호자의 관계 중요성을 제시함으로써 장애인 구강건강관리법 및 관심도를 높일 수 있는 정책적 지원 및 연구가 필요할 것으로 사료된다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권9호
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• pp.916-920
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• 2008

개인 컴퓨팅 환경은 사용자에 특화된 응용프로그램 및 설정, 사용자 데이타 등을 총칭하는 개념으로써, 노트북, UMPC 등의 휴대용 컴퓨팅 H/W는, 어떤 곳에서도 항상 개인에게 특화된 컴퓨팅 환경에서 작업 가능하도록 소형화, 경량화가 진행되고 있다. 그러나, 최근 가상화 기술 및 휴대용 스토리지 기술을 이용한 다양한 개인 컴퓨팅 환경 이동성 지원 기술이(c.f. VMWare Pocket ACE[1], Mojopac[2], u-PC[3] 등) 등장함으로써, 공용 PC 상에 자신의 컴퓨팅 환경을 로딩하여 사용할 수 있도록 지원하는 기술이 주목받고 있다. 특히, 본 논문의 이전 연구로써, u-PC[3]에서는 UPnP 및 iSCSI 프로토콜을 이용하여 사용자 영역 네트워크(PAN)상에서 자동 검색 및 구성이 가능한 무선 스토리지 기술과, Windows 운영체제 상에서 구동 가능한 개인 컴퓨팅 환경 이동성지원 기술을 제안하였다. 그러나, 기존의 u-PC 기술에서는, Windows 운영체제 상 Filter Driver 계층에서 IRP(I/O Request Packet) forwarding을 이용하여 개인 컴퓨팅 환경의 이동성 지원 기술을 구현함으로써, 제한적인 응용 프로그램만 구동 가능한 한계점이 있었다. 본 논문에서는 Windows 운영체제 상 System Call Hooking 기법을 이용하여 운영체제 가상화 기술을 구현하고, 개인 컴퓨팅 환경의 이동성을 지원함으로써, 기존 논문에서의 한계성을 극복하였으며, VMWare Pocket ACE, Mojopac 등의 단점인 개인 컴퓨팅 환경의 구동 초기화 오버 헤드를 극복하였다. 또한, Ultra Wide Band (UWB) 기반 고속 무선 네트워크 상 적용 가능한 무선스토리지 기술을 개발하고, 개선된 u-PC 플랫폼을 연동하여 다양한 형태의 개인 컴퓨팅 환경 사용 모델을 제시함으로써 기술의 적용성을 검증하였다.

• Journal of Periodontal and Implant Science
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• 제28권1호
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• pp.37-56
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• 1998

The purpose of this study was to evaluate the clinical and microbiological outcomes following the use of 30% minocycline-loaded polycaprolacton film and 2% minocycline-loaded gel that was applied locally into pockets combined with scaling and root planing. 25 human subjects who were non-pregnant, non-lactating, aged 20-50 and diagnosed as moderate to advanced adult periodontitis were enrolled. Subjects were excluded if they had a history of severe acute or chronic systemic disease, if they required antibiotic prophylaxis for dental treatment for any reason, or if they reported a history suggestive of hypersensitivity reactions to minocycline or tetracycline. 4quadrants that had several teeth with a 5-8mm probing pocket depth and radiographic evidence of alveolar bone loss for each patient were selected and divided into test sites and control sites according to the split-mouth design. Scaling and root planing was done for each site at baseline(0week). Test sites received the minocycline gel and strip and control sites had saline irrigation. The patients received both treatments simyltaneously. Subgingival irrigation of sterile saline was applied to the control sites for approximately 30 seconds. Minocycline strip and gel was applied into the periodontal pocket at 1, 2, 3, 4 weeks each after scaling and root planing in the test sites. The clinical and microbiological measurements were made at baseline and at the follow-up visits 6, 10, 14, 20 weeks. The results of this study were as follows; 1. The sulcular bleeding index, probing pocket depth and Periocheck test was significantly reduced and the relative proportions of spirochetes and motile rods were significantly reduced and the proportion of cocci was correspondingly increased, in locally delivered minocycline strip group compared to saline irrigation group. 2. In locally delivered minocycline gel group, The effect was the same with minocycline strip group as compared with saline irrigation therapy. 3. There was no significant differences between minocycline strip group and minocycline gelgroup. In conclusion, minocycline HCl local drug delivery combined with scaling and root planing may provide added improvement of clinical and microbiological responses by inhibiting bacterial recolonization of treated sites. It is suggested that the local administration of minocycline-HCl in the periodontal pocket is effective when combined with subgingival mechanical debridement.