• 해양환경안전학회지
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• 제28권7호
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• pp.1209-1215
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• 2022

선택적 촉매 환원법(SCR)은 질소산화물(NO_x)을 저감하는 매우 효율적인 방법으로 알려져 있으며 발생된 질소산화물(NO_x)을 질소(N₂)와 수증기(H₂O)로 환원시키는데 촉매 작용을 한다. 질소산화물(NO_x) 저감 성능을 결정하는 요소 중 하나인 촉매는 셀 밀도가 증가하면 촉매효율이 증가하는 것으로 알려져 있다. 본 연구에서는 실습선 세계로호에 설치되어 있는 발전 기관의 배기가스 조건을 모사한 실험장치를 통하여 100CPSI(60Cell)촉매의 부하에 따른 질소산화물(NO_x) 저감 성능을 확인하고 세계로호에 설치되어 있는 25.8CPSI(30Cell) 촉매의 기존 연구 자료와의 비교를 통해, 셀 밀도가 질소산화물(NO_x)의 저감에 미치는 영향에 대하여 고찰하였다. 실험용 촉매는 셀 밀도만 변화를 주었고 형태는 벌집형(honeycomb), 조성물질은 V₂O₅-WO₃-TiO₂를 동일하게 사용하여 제작하였다. 실험결과 100CPSI(60Cell) 촉매의 질소산화물(NO_x) 농도 저감율은 평균적으로 88.5%이며 IMO specific NOx 배출량은 0.99g/kwh로 IMO Tier III NOx 배출기준을 만족하였다. 25.8CPSI(30Cell) 촉매의 경우, 질소산화물(NO_x) 농도 저감율은 78%, IMO specific NOx 배출량은 2.00g/kwh 이었다 두 촉매의 NOx 농도 저감율과 IMO specific NOx 배출량을 비교하였을 때, 100CPSI(60Cell)촉매가 25.8CPSI(30Cell) 촉매보다, NOx 농도 저감율은 10.5% 높고 IMO specific NOx 배출량은 약 2배 적은 것을 확인하였다. 따라서 촉매의 셀 밀도를 높임으로써 효율적인 탈질효과를 기대할 수 있으며 향후 실선 테스트를 통하여 검증한다면 촉매의 부피 저감을 통한 제작 비용을 줄이고 협소한 선박 기관실을 효율적으로 사용하기 위한 실용적인 자료로서 기대된다.

• 셀메드
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• 제1권1호
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• pp.4.1-4.4
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• 2011

Excessive stress is harmful to academic performance in children and may lead to dropping out of school. To meet the demands of a modern life-style which is full of speed, stress and tension, an all-round child health program is crucial. The use of yoga for children has diverse applications in maintaining and developing their physical, mental, intellectual, emotional and spiritual levels. Yoga, through its physical postures (asana), breathing practices (pranayama), cleansing techniques (kriya), meditation therapies (dhyana) and relaxation training (yoga nidra) yields a positive effect in the management of stress in children. Yoga practice benefited children by improving their eye-hand coordination, attention span, levels of concentration, competitive performance and relaxation. Visually impaired children showed a significant decrease in their abnormal anxiety levels when they practiced yoga for three weeks, while a program of physical activity had no such effect. Socially disadvantaged children in a remand home showed significant improvements in sleep, appetite and general well being, as well as a decrease in physiological arousal after yoga. In one study, it is found that a 4-week program of asana and meditation lowers the aggressive behavior of children. Meditation helped to reduce problems related to maladaptive behavior, increase emotional and physical health and psychological well-being in children. Finally, the possible role of yoga in improving the mental state and general well-being of children with cancer is being explored.

• 환경영향평가
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• 제10권1호
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• pp.1-8
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• 2001

Detection of red tides by satellite remote sensing can be done either by detecting enhanced level of chlorophyll pigment or by detecting changes in the spectral composition of pixels. Using chlorophyll concentration, however, is not effective currently due to the facts: 1) Chlorophyll-a is a universal pigment of phytoplankton, and 2) no accurate algorithm for chlorophyll in case 2 water is available yet. Here, red band algorithm, classification and PCA (Principal Component Analysis) techniques were applied for detecting patches of Cochlodinium polykrikoides red tides which occurred in Korean waters in 1995. This dinoflagellate species appears dark red due to the characteristic pigments absorbing lights in the blue and green wavelength most effectively. In the satellite image, the brightness of red tide pixels in all the three visible bands were low making the detection difficult. Red band algorithm is not good for detecting the red tide because of reflectance of suspended sediments. For supervised classification, selecting training area was difficult, while unsupervised classification was not effective in delineating the patches from surrounding pixels. On the other hand, PCA gave a good qualitative discrimination on the distribution compared with actual observation.

• 한국수학교육학회지시리즈A:수학교육
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• 제52권4호
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• pp.517-529
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• 2013

The purpose of this study is to investigate pre-service teachers' perceptions and their difficulties of mathematics instruction. Pre-service teachers have positive perceptions about teaching students and teaching profession through teaching practicum. In addition, they have perceived that teaching practicum can enhance teaching methods for their students. Especially, they suggested that cooperating teachers' instruction and mathematics teachers and their colleagues' classroom observation are important factors to improve their teaching methods. In other hands, they have difficulties in application of questions encouraging mathematical thinking, attention concentration considering students' interest and planning and performing for mathematics instruction class according to levels of students' study abilities. Based upon this study's findings, teacher education institutes should make efforts to alleviate difficulties in mathematics instruction through effective teaching practicum such as regular reflection activities for their classes, programs development associated with schools, pre-training and education programs for guidance teachers.

• 한국병원경영학회지
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• 제7권3호
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• pp.25-43
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• 2002

This study focuses on the factors that make the financing decision of private hospitals in Korea. Data used in this study were collected from 98 hospitals with complete general data of current status as well as financial statements. They were chosen from the 138 hospitals that passed the accreditation process by the Korean Hospital Association from 1996 to 2000 for the purpose of accrediting training hospitals. The dependent variables in this study consist of total liabilities to total assets, borrowings to total assets. The independent variables are ownership, hospital type, teaching status, location, bed size, period of establishment, asset structure, profitability, growth, tax shields, volatility of profit, competition(market concentration), and other factors. The major findings of this study are as follows. The factors found to have significant effect on liabilities to total assets are teaching status(-), asset structure(-), profitability(-), tax shields(+), and business risk(-). University hospitals have less liabilities than the non-university hospitals. It was also confirmed that high profitability, high fixed asset, high volatility of profit and low tax shields results in decrease in liabilities. The factors that significantly affect on borrowings to total assets are teaching status(-), period of establishment(-), volatility of profit(-) and competition(+).

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2002년도 춘계학술대회 논문집
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• pp.21-29
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• 2002

가스계 소화약제시스템의 인명안전 또는 기타 안전관련으로 CO2 시스템과 청정약제시스템을 중심으로 기술해보았습니다. 인명에 대한 위험을 최소화하면서 CO2 소화시스템의 혜택을 얻기 위해서는 설계, 시공, 유지관리면에서의 인명안전에 대해 상당한 관심을 기울여야한다. 청정 소화약제를 통상의 거주구역에 사용할 경우의 주요요소는 독성문제이다. 할로겐화탄소약제 테스트에서의 주요 관점은 급성효과, 즉 단기간 노출의 경우이다. 주요급성효과에는 마취성과 심장감작성이 있다. 불활성가스약제의 경우 주요 신체적 영향으로는 산소농도의 저하문제를 들 수 있다.

• 의학교육논단
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• 제17권2호
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• pp.60-68
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• 2015

The majority of medical educators agree that scientific education is critical to the development of physician-scientists. However, the proportion of physicians interested or engaged in research has been decreasing. To overcome this deficit of research oriented physicians, many medical schools in the United States have introduced scholarly concentration (SC) programs into their medical curricula since 2000. In contrast, Korea has very few medical schools with such programs. Research programs at American medical schools were surveyed and investigated in order to better design and develop SC programs appropriate for Korean medical schools. Information on SC programs was gathered by reviewing medical school web sites and related articles. The SC programs of Brown Alpert Medical School, University of Pittsburgh School of Medicine, Duke University School of Medicine, and Stanford University School of Medicine are discussed in depth. The characteristics of each program were organized into seven parts: program description, administrative structure, orientation, curricular content, mentors and mentoring, student evaluation, and challenges. For a successful SC program in Korea we must consider providing guaranteed time for SC programs with necessary modifications in the core medical curriculum, educating and training of mentors, providing orientation and motivating students to pursue research, developing curricula for SC programs, and evaluating the progress of SC projects.

• 생약학회지
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• 제47권1호
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• pp.18-23
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• 2016

This study was conducted to investigate the tyrosinase inhibitory and melanin production inhibitory activity of the distilled water extract of Dendropanax morbifera leaf (DMW) and the fermented extract by Lactobacillus plantarum (DMF). DMF was prepared by inoculation of L. plantarum after the extraction procedure with distilled water. Fermentation for 48 hours at $37^{\circ}C$ is the most effective condition in this study. In DPPH radical scavenging ability, $SC_{50}$ values of the fermented DMF was $37.9{\mu}g/ml$ as a result of more effective than DMW extract ($52.6{\mu}g/ml$). Moreover, tyrosinase inhibitory activity of DMF showed higher activity than DMW. In nontoxic concentration range, DMF showed strong melanin production inhibitory effect in ${\alpha}$-melanocyte stimulating hormone-stimulated B16F10 cell. As a result, the fermentation of the distilled water extract of D. morbifera leaf by L. plantarum could be applicable to functional materials production for skin-whitening agents.

• 보건의료산업학회지
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• 제5권1호
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• pp.133-145
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• 2011

The purpose of this study is to analyze the influence of external environment, organizational characteristics on informatization level in hospital settings, and to provide suggestions to improve the informatizaiton level of strategic information system of hospitals. In order to achieve study purpose, causal model was developed and empirically tested. Data were collected from 716 managers of 89 hospitals keeping information system in Busan and KyungNam Province using self-administered structured questionnaire. Major results of this study were as follows; First, among hospitals which had information training programs, informatization capacity was significantly higher. Moreover, informatization capacity was significantly varied by ownership type, institutional level, and number of beds of hospitals. Second, environmental uncertainty, intra-industry competition intensity, decision-making concentration, work standardization variables and perceived benefits were found to be significant affecting factors on informatization capacity as a result of path analysis. Third, support of top-management and perceived benefits were found to be significant affecting factors on informatization capability as a result of path analysis. Especially, informatization capability was positively affected by informatization capacity. Finally, perceived benefits was found to be significant affecting factors on informatization competency as a result of path analysis. Especially, informatization competency was positively affected by informatization capability.

• 간호행정학회지
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• 제20권3호
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• pp.281-291
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• 2014

Purpose: The purpose of this study was to identify employment experiences of nurses caring for hospitalized foreign patients. Methods: For this study, 10 nurses caring for foreign patients for more than 6 months were chosen purposively. Data were collected through in-depth individual interviews from July to September 2013 and analyzed in terms of Giorgi's phenomenological methodology. Results: Five themes-clusters were identified from fifteen themes; 1) Awesome challenges; 2) Laborious dealing with barriers; 3) Acceptance of cultural differences; 4) Complete concentration of personal energy; 5) Taking a powerful step towards tomorrow. Conclusion: Results of this study reveal the significance of nurses' experiences in caring for foreign patients for the first time in Korea. The following are suggested: First, facilitation and training is necessary for language proficiency, communication skills and ability to understand cultural traits of foreign patients. Second, manuals and international guidelines for caring for foreign patients should be systematically developed to improve quality of healthcare services.