• 대한조선학회논문집
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• 제47권2호
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• pp.113-121
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• 2010

Recently, as container ships become larger and faster, rudder cavitations are more frequently observed near the gap between the horn and rudder plates of the ships to cause serious damages to the rudder surface of the ship. The authors already have suggested through a series of model experiments and numerical computations that employment of an appropriate blocking device for gap flow may retard the gap cavitation. For examples, a cam device installed near the outer edges of the vertical gap or a water-injection device combined with a pair of half-round bars installed inside the gap can considerably reduce the gap cavitation. However, it is also found that effective blocking of the flow through the vertical gap results in growth of the cavitation near the horizontal gap instead. In the present study, effectiveness of the simultaneous blocking of the flow through the horizontal and vertical gaps of a horn type rudder in minimizing the damage by gap cavitation is studied. Additional blocking disks are inserted inside the horizontal gaps on the top and bottom of the pintle block and numerical computations are carried out to confirm the combined effect of the blocking devices.

• 한국안광학회지
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• 제11권2호
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• pp.85-89
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• 2006

렌즈 절삭공구의 기계적 특성을 향상시키는 기구에 관한 연구를 하기 위해, 탄화규소와 탄화티타늄을 주재료로 사용되었다. 또한, 소결첨가제로 알루미나와 이트리아를 첨가하였다. 첨가제 조성비는 알루미나와 이트리아비를 1:1로 유지하였다. 이를 $1810^{\circ}C$에서 1시간 일축가압 소결 후 $1860^{\circ}C$에서 3, 6 그리고 12시간 동안 열처리하였다. 열처리 시간이 길어질수록 입자크기는 점점 증가하였다. 미세구조는 주사전자현미경으로 관찰하였으며 이미지프로그램(Image-Pro Plus, Media Cybernetics, Maryland, U.S.A.)으로 상분석 하였다. 파괴기구는 주로 길게 자란 탄화규소 입자에 의한 균열회절에서 일어나고 있음을 알 수 있다. 균열회절기구에 영향을 미친 SiC입자들은 대부분 두께가 $2.3{\mu}m$ 이하였고, 장경비는 2.5 이상이었다. 균열가교도 일부 파괴인성 증진기구에 기여함을 알 수 있다.

• 한국콘텐츠학회논문지
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• 제14권9호
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• pp.463-475
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• 2014

21세기의 신성장 동력으로 여겨지고 있으며 최근에 급격한 양적 및 질적 성장을 하고 있는 의료관광이나 우리나라가 제공하는 의료관광 상품이 아직 의료 관광객의 필요에 충분히 부응하지 못하는 측면이 있다. 이의 해법을 의료관광속성에 관한 연구에서 찾고자 한다. 여기에 2000년 이후 꾸준히 성장세를 유지하고 있는 한류에 대한 관심의 정도가 의료관광에 영향을 미치는지도 확인한다. 이를 위해 5가지 가설이 설정되었고 가설검증을 위해 설문을 통한 실증분석을 실시하였다. 실증분석을 위해 SPSS 20.0 통계프로그램을 활용하였고, 설정된 가설은 검증결과 모두 채택되었다. 가설검증결과 한류에 대한 관여도는 의료관광속성, 만족도 및 행동의도에 영향을 미쳤으며 의료관광속성도 만족도 및 행동의도에 영향을 미침을 확인하였다.

• 유통과학연구
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• 제1권1호
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• pp.1-24
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• 1999

CALS/EC is about doing business electronically. It is based on the electronic processing and transmission of data, including text, sound and video. It encompasses many diverse activities including electronic trading of goods and services, online delivery of digital content, electronic fund transfers, electronic share trading, electronic bills of lading, commercial auctions, collaborative design and engineering, online sourcing, public procuremet, direct consumer marketing, and after-sales service. It involves both products(e.g. consumer goods, specialised medical equipment) and services(e.g. information services, financial and legal services); traditional activities(e.g. healthcare, education) and new activities (e.g. virtual malls). CALS/EC will be emerging to replace and substitute the role of the conventional market. By changing and eliminating some processes of the transactions, the electronic market and the electronic commerce will redistribute the power and hence the benefits of the market activities. Traditional way of doing business may enter into the new electronic market because the role and function of trust and established reputation will be reinforced in the electronic market. The CALS/EC through the Internet has been in the spotlight in the shopping behavior of the consumers. Accordingly Corporates are trying to adapt themselves to those rapidly changing environments being affected by the Internet. Among others, particularly to be noted is the CALS/EC between corporations and consumers whose potential growth can be considered very substantial. This report, focusing on the introduction of CALS/EC for the logistics of SMEs, will allow us to prepare more efficiently for the coming 21st Century. It is obvious that CALS/EC is fast becoming the useful way of exchanging not only information but products in business between firm-to-firm and firm-to-customer.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2016년도 추계학술대회 논문집
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• pp.105-105
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• 2016

Recently, high power impulse magnetron sputtering (HIPIMS) has attracted considerable attentions due to its high potential for industrial applications. By pulsing the sputtering target with high power density and short duration pulses, a high plasma density and high ionization of the sputtered species can be obtained. HIPIMS has exhibited several merits such as increased coating density, good adhesion, microparticle-free and smooth surface, which make the HIPIMS technique desirable for synthesizing hard coatings. However, hard coatings present intrinsic defects (columnar structures, pinholes, pores, discontinuities) which can affect the corrosion behavior, especially when substrates are active alloys like steel or in a wear-corrosion process. Atomic layer deposition (ALD), a CVD derived method with a broad spectrum of applications, has shown great potential for corrosion protection of high-precision metallic parts or systems. In ALD deposition, the growth proceeds through cyclic repetition of self-limiting surface reactions, which leads to the thin films possess high quality, low defect density, uniformity, low-temperature processing and exquisite thickness control. These merits make ALD an ideal candidate for the fabrication of excellent oxide barrier layer which can block the pinhole and other defects left in the coating structure to improve the corrosion protection of hard coatings. In this work, CrN/Al2O3/CrN multilayered coatings were synthesized by a hybrid process of HIPIMS and ALD techniques, aiming to improve the CrN hard coating properties. The influence of the Al2O3 interlayer addition, the thickness and intercalation position of the Al2O3 layer in the coatings on the microstructure, surface roughness, mechanical properties and corrosion behaviors were investigated. The results indicated that the dense Al2O3 interlayer addition by ALD lead to a significant decrease of the average grain size and surface roughness and greatly improved the mechanical properties and corrosion resistance of the CrN coatings. The thickness increase of the Al2O3 layer and intercalation position change to near the coating surface resulted in improved mechanical properties and corrosion resistance. The mechanism can be explained by that the dense Al2O3 interlayer acted as an excellent barrier for dislocation motion and diffusion of the corrosive substance.

• 한국식품과학회지
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• 제22권5호
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• pp.533-538
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• 1990

풀루란 발효에서 500rpm에서 통기속도를 0.5vvm, 1.0vvm, 2.0vvm으로 증가시켰을 때 최대 비성장속도는 $0.168(hr^{-1})$에서 $0.192({hr^{-1})$로 증가되었으며 풀루란의 최대 비생산속도는 $0.046({hr^{-1})$에서 $0.093({hr^{-1})$으로 증가되었다. 풀루란 발효액의 물성은 power-law를 따르는 Pseudoplasticity를 나타냈으며 Power-law 변수들과 풀루란 농도 사이에는 $lnK(t)=ln({\tau})_o-n(t)\;ln({\gamma})_o$와 $K(t)=AP(t)^B$의 상관관계를 보였다.

• 컴퓨터교육학회논문지
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• 제19권1호
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• pp.63-76
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• 2016

사이버불링의 피해가 점차 증가하고 있다. 이에 따라 사이버불링에 대한 법률 및 교육적 대응과 더불어, 기술(code)에 의한 대응도 요구되고 있다. 본 연구에서는 이러한 기술적인 해결 방법 중 하나로 가상 체험형 시뮬레이션의 장점을 이용하고자 하였다. 본 연구에서 개발한 적용 모형은 인지${\rightarrow}$판단${\rightarrow}$결정${\rightarrow}$행동의 각 단계 및 수준을 거치며, 사이버불링에 대한 예방 및 학습을 하게 된다. 각 단계의 세부 모형은 프리브리핑${\rightarrow}$시나리오제시${\rightarrow}$반응요구${\rightarrow}$반응참여${\rightarrow}$결과 및 피드백${\rightarrow}$성장${\rightarrow}$디브리핑으로 구성된다. 이와 같이 사이버불링 예방 및 관련 교육을 하고자 가상체험형 시뮬레이션 적용 모형을 개발하고 이를 바탕으로 실제 구현하였다. 본 연구에서 개발한 모형과 시뮬레이션이 사이버불링의 피해를 줄이는데 도움이 되기를 기대한다.

• 한국건강관리협회지
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• 제2권2호
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• pp.187-197
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• 2004

Owing to continuous economic growth, an increased standard of living, and improvements to health care in Korea, the life expectancy of Koreans rose from 69.0 years in 1985 to 71.3years in 1990. It continued to rise throughout the 1990s, and, by 2002, had reached 76.5years for the general population and 80.0 years for Korean females. Similarly, the percentage of the Korean population that is 65 years of age or older increased from 3.1 in 1970 to 7.1in 2000, and is expected to reach approximately 14,0 in 2019. Thus, according to this estimate, Korea will have evolved from an "aging society" to an "aged society" in only 19years. In the case of other countries, this same transformation has generally taken 2 to 5times longer. One of the major issues related to Korea's rapidly aging population relates to the health problems of the elderly. According to the 2002 National Health Survey Report, 87,6 percent of the elderly were reported to Have at least one chronic disease. In other words, almost 9out of every 10 elderly persons in Korea were suffering from a chronic illness, This, clearly, places a significant economic burden on Korean society in the form of increased health care Costs. This paper examines the increasing prevalence of chronic diseases within Korea's rapidlv aging population and offers some possible short- and long-term solutions to cope with the increased burden being placed on Korea's health care system. These include the basic services at local health centers for the elderly and the national life-long health promotion programs that aim to correct unhealthy behavior, such as smoking, the excessive use of alcohol, and poor eating and exercise habits.

• 통상정보연구
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• 제1권1호
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• pp.179-201
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• 1999

물류의 흐름을 배제한 CALS/EC는 있을 수 없다. CALS/EC에서도 거래의 최종단계는 고객이 요구하는 상품 또는 서비스를 전달하는 것이기 때문이다. CALS/EC를 이용한 물류정보화가 물류 문제 해결에 도움을 줄 수 있고, 전자상거래의 활성화를 가로막는 물류 문제를 분석하기 위해 새로운 환경에서의 물류 요구의 변화를 분석하였다. 전자상거래와 물류정보화 활성화와 관련하여, 전자상거래 등 산업활동의 정보화 추이를 고려한 물류체계의 고도화, 산업전반의 물류정보화 촉진을 위한 법 제도의 개선, 물류산업전반의 경쟁력 제고를 위한 규제개혁 추진, 전자상거래 활성화률 위한 통관체제의 개선 등이 필요하다.

• 복식문화연구
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• 제20권2호
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• pp.195-207
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• 2012

In South Korea, the growth of online shopping malls that are overtaking traditional offline distributors in sales requires the latter to concentrate on developing a variety of contents amidst the ever-changing and competitive market environment. First of all, attention should be paid to information on fashion item materials. This study examined the current status of online shopping malls with a focus on their three different types-specialized malls, general malls, and open markets-and investigated consumers' hedonic shopping motives and influence on fashion materials in terms of purchasing behavior. In doing so, this study surveyed men and women in their 20s-30s residing in Seoul or its surrounding cities and used a total of 255 questionnaires for statistical analysis. The statistical software program SPSS 15.0 was used to conduct frequency analysis, factor analysis, reliability analysis, and multiple regression analysis. The study results showed that in general and specialized shopping malls, consumers granted greater reliability and importance to fashion materials when their interest in shopping or attention to fashion items/brands was high and when they wanted rare items. In open markets, the more interest consumers had in shopping and the more sensitive they were to fashion information, the more dependent they were on prices; in other words, prices were found to have a greater influence on their purchase decisions than the quality of fashion materials. The findings of this study would be useful to marketers and distributors who are trying to develop their marketing strategies based on fashion material information, according to the different types of online shopping malls.