• 한국항공우주학회지
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• 제33권10호
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• pp.98-103
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• 2005

해상도 2.5m 급 지구관측 카메라인 MAC(Medium-sized Aperture Camera)의 비행모델이 정렬 및 조립되었다. 본 논문에서는 지상에서 측정한 MAC의 시스템 MTF 성능, MTF를 이용한 초점면부의 정렬 등에 대해 논의한다. 칼날주사방식을 이용하여 MAC의 시스템 MTF를 측정하였고, 이를 위해 회절한계 성능의 구경 450 mm 급의 카세그레인 시준기를 만들어 사용하였다. 시스템 MTF를 이용하여 CCD 검출기 초평면부의 최적의 초점에 정렬하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.419-423
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• 2005

2차원 하천흐름. 유사이동, 오염확산 해석을 위해서는 유한요소법(FEM) 등을 활용한 수치해석 모델이 사용되며, 이 때 모델링을 위해서 모의영역은 2차원의 요소망으로 구성하게 된다. 기존 국내 연구에서는 이러한 2차원 요소망 생성 및 수치해석을 위해 SMS 및 CCHE2D와 같은 외국의 상용 프로그램을 이용하였으나, "수자원의 지속적 확보기술개발 사업"의 일환으로 수행중인 "RAMS(River Analysis and Modeling System) 개발" 과제를 통해 순수 국산 2차원 수리해석 소프트웨어가 개발 중에 있다. 본 연구에서는 RAMS를 비롯한 기타 수리해석 모델에서 사용 가능한 2차원 범용 요소망 생성 프로그램을 개발하고자 다양한 요소망 생성 기법 및 국외 상용 2차원 수리해석 모델 프로그램에서의 메쉬 생성방법 등을 분석하여 프로토타입 메쉬 생성기를 개발하였다. 현재 개발 중인 요소망 생성 프로그램은 요소망 생성을 위한 기본 기능 외에도 생성된 요소망 데이터를 RAMS에 포함되어 있는 다양한 2차원 유한요소 모형의 입력자료 형태로 변환함으로써 수리해석에 적용가능하다. 이러한 범용 2차원 요소망 생성 프로그램의 개발은 안정적인 수치해석의 기반을 제공하고 다양한 하천흐름, 유사, 수질 해석 모델과 연계함으로써 하천의 수리학적인 거동을 보다 정확히 모의할 수 있을 것으로 기대된다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2003년도 추계학술대회 및 정기총회
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• pp.129-132
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• 2003

본 연구에서는 사이버 교육(e-Learning)에서 컨텐츠 정보특성, 인터페이스 특성, 브랜드인지도, 부가서비스 제공 여부, 강사의 능력, 기술인프라 정도, 놀이성, 지각위험 등이 전반적인 만족도, 신뢰, 몰입 및 재구매 의도에 미치는 영향에 관하여 연구하고자 한다. 연구의 대상은 세 가지로 나누어 기업의 사내교육대상자, 학원 등 사교육대상자 및 대학교육대상자 등의 사이버 교육의 피교육자 유형에 따라 어떠한 e-Learning의 특성이 전반적인 만족도, 신뢰, 몰입 및 재구매 의도에 영향을 미치는가를 조사하기 위한 것이다. 연구모형에 포함된 변수는 기존의 연구에 근거하되 e-Learning의 특성적 요인을 포함하여 선정하였다. 사이버 공간에서 구매행위에 관한 연구는 다수의 연구자들(Jarvenpaa 등, 1997; Eugene 등, 1995; Parasuraman 등 1996; Spiller 등, 1998; O'keefs 등, 1998, Li, 등, 1999; Donthu 등, 1999; Macintosh 등, 1997; Garbarino 등, 1999)에 의해 다양한 방법으로 연구가 진행되었지만 본 연구에서는 e-Loaming의 환경적 특성에서 종합적 연구를 하고자 한다. 따라서 기존의 인터넷 환경 하에서 행해진 인터넷 컨텐츠의 특성에 관한 연구를 기반으로 사이버 교육(e-Loaming)의 특성과 부합하는 변수들을 연구 모형에 포함하였으며, 또한 사이버 교육에서 새롭게 부각되는 요인들을 부가하여(이승희, 2001; 박광태 등, 2002; Bonk, 2002; Learning Decisions, 2001) 연구모형을 설정하고 이를 근거로 실증연구를 수행 중에 있다.

• Journal of Preventive Medicine and Public Health
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• 제43권6호
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• pp.472-478
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• 2010

Cancer is a leading cause of death around the world. Education is at the core of cancer prevention activities, especially programs targeting empowering existing public health workforce. In the past 10 years, researchers at the University of Pittsburgh have been building the Global Health Network Supercourse project, a library of over 4500 online lectures and a network of nearly 50000 public health professionals in 174 countries. As of November 2010, the overall number of Supercourse participants from Asia exceeds 7000 participants. The Supercourse network has been investigating methods for Internet based recruitment of cancer prevention professionals in order to network cancer experts locally and globally, including the use of mHealth technologies for cancer research education and for NCD registries. Supercourse is a tool that can offer a solution to the challenges of information sharing, especially in the field of NCDs and cancer. In this paper, we highlight the need for the development of Cancer Supercourse with Satellite in Asia and encourage faculty members from Asia to join the network.

• Journal of Trauma and Injury
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• 제18권1호
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• pp.41-46
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• 2005

Background: We evaluated the clinical and the radiological results of treatment for humeral shaft fractures by using an antegrade intramedullary nail. Methods: Thirty-nine (39) cases of humeral shaft fractures treated with antegrade intramedullary nail were evaluated. Bone union was evaluated with simple radiographic findings, and a functional evaluation was done using the American Shoulder and Elbow Surgeons (ASES) score. Results: The average duration until union was 14.1 weeks. On the functional evaluation using the ASES score, 15 cases were excellent, 19 cases good, 3 cases fair, and 2 cases poor. Conclusion: We conclude that antegrade intramedullary nailing has a good clinical and radiological result for treatment of humeral shaft fractures.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.116-122
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• 2007

An efficient enzyme system for the synthesis of L-tyrosine was developed using a fed-batch reactor with continuous feeding of phenol, pyruvate, and ammonia. A thermo- and chemostable tyrosine phenol-lyase from Symbiobacterium toebii was employed as the biocatalyst in this work. The enzyme was produced using a constitutive expression system in Escherichia coli BL21, and prepared as a soluble extract by rapid clarification, involving treatment with 40% methanol in the presence of excess ammonium chloride. The stability of the enzyme was maintained for at least 18 h under the synthesis conditions, including 75 mM phenol at pH 8.5 and $40^{\circ}C$. The fed-batch system (working volume, 0.51) containing 1.0 kU of the enzyme preparation was continuously fed with two substrate preparations: one containing 2.2 M phenol and 2.4 M sodium pyruvate, and the other containing 0.4 mM pyridoxal-5-phosphate and 4M ammonium chloride (pH 8.5). The system produced 130g/I of L-tyrosine within 30h, mostly as precipitated particles, upon continuous feeding of the substrates for 22 h. The maximum conversion yield of L-tyrosine was 94% on the basis of the supplied phenol.

• Journal of Applied Biological Chemistry
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• 제50권2호
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• pp.41-45
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• 2007

Polaromonas naphthalenivorans CJ2, responsible for naphthalene degradation at a coal tar contaminated site, was isolated on MSB agar media supplied with naphthalene vapor as the sole carbon source at $10^{\circ}C$. The strain is not isolated under the same isolation condition using the same soil sediment at $20^{\circ}C$ although its optimum temperature is about $20^{\circ}C$. In this work we explored the reason why strain CJ2 could not have been isolated on MSB agar with naphthalene vapor at $20^{\circ}C$. Dispersed CJ2 cells in PBS buffer formed colonies on MSB agar with naphthalene vapor at $10^{\circ}C$ with low naphthalene vapor pressure, but not at $20^{\circ}C$ with high naphthalene vapor pressure. However, streaked cells without resuspension grew on MSB agar with naphthalene vapor at $10^{\circ}C,\;20^{\circ}C$, and even $25^{\circ}C$. Investigation of scanning electron microscopy showed that CJ2 cells formed extracellular polysaccharide (EPS) capsules, which were released easily from CJ2 cells by just dispersion. Therefore, it is concluded that strain CJ2 is able to overcome the naphthalene toxicity by forming a capsule-type barrier around the cells although it is susceptible to naphthalene toxicity at high temperature.

• 유통과학연구
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• 제16권10호
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• pp.5-21
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• 2018

Purpose - This case study reviews the development history of Lotte Shopping, which has played a key role in modernizing Korea's retail industry. Research design, data, and methodology - Lotte Shopping's expansion to various channel types has been reviewed from the perspective of the resource-based view of strategy. The opening of Lotte Department Store in 1979 signaled the beginning of the modernized distribution system in Korea. Lotte Shopping expanded its business domains to various types of retail channels, such as discount stores, online shopping malls, TV home shopping, convenience stores, supermarkets, home appliances specialty stores and health & beauty stores. Results - Lotte Shopping has been able to maintain high level of customer satisfaction with leading merchandising skills. It has developed mutually beneficial relationship with the partner firms. It has also been a leading firm in implementing corporate social responsibility activities and environment-friendly management. Lotte Shopping has applied advanced information and communication technology to provide customized goods/services. Conclusions - This study summarizes the business environment and new challenges Lotte Shopping faces currently. Lotte Shopping is trying to reinforce the omni-channel strategy, which can create synergy among various distribution channels based on its core competences.

• Journal of Microbiology and Biotechnology
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• 제27권8호
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• pp.1519-1528
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• 2017

Foodborne contamination and salmonellosis caused by Salmonella Enteritidis (S. Enteritidis) are a significant threat to human health and poultry enterprises. Outer membrane vesicles (OMVs), which are naturally secreted by gram-negative bacteria, could be a good vaccine option because they have many biologically active substances, including lipopolysaccharides (LPS), outer membrane proteins (OMPs), and phospholipids, as well as periplasmic components. In the present study, we purified OMVs derived from S. Enteritidis and analyzed their characteristics through silver staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis. In total, 108 proteins were identified in S. Enteritidis OMVs through liquid chromatography tandem mass spectrometry analysis, and OMPs, periplasmic proteins, and extracellular proteins (49.9% of total proteins) were found to be enriched in the OMVs compared with bacterial cells. Furthermore, native OMVs used in immunizations by either the intranasal route or the intraperitoneal route could elicit significant humoral and mucosal immune responses and provide strong protective efficiency against a lethal dose (~100-fold $LD_{50}$) of the wild-type S. Enteritidis infection. These results indicated that S. Enteritidis OMVs might be an ideal vaccine strategy for preventing S. Enteritidis diseases.

• Journal of Welding and Joining
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• 제33권3호
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• pp.40-46
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• 2015

Welding is one of the most fundamental and necessary work in the industry that demand sophistication of skilled workers. This study is to introduce welding simulator as a training tool, to verify its effectiveness and to measure satisfaction of the trainees. A group of freshman students at a Korea Polytechnics College in their twenties with less experience of welding participated in the study. They were divided into two groups and took a traditional training course (comparison group) and a training course with welding simulator applied reality/haptic technology (experimental group) for same hours respectively. To evaluate training effect, a national certificate test and a survey based on Phillips' ROI (Return on Investment) methodology were conducted by the students and the college respectively. And satisfaction survey among the students based on Kirkpatrick's Four-Level Evaluation Model was also carried out. The results showed that all students in the experimental group passed the national certificate test and the ROI of the experimental group for five years were 110% higher than the comparison group. Furthermore, 25% more students in the experimental group replied "very satisfied" about the overall training course and 75% more students in the same group found that the simulation was very similar to the real welding.