• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2008년도 추계학술발표논문집
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• pp.101-104
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• 2008

일반적으로 연속경간을 가지는 강합성 I-형강 교량에 있어서 내부 지점 부근에서 상대적으로 큰 부모멘트가 발생하므로, 이에 경제적인 단면 활용을 위하여 변단면을 적용하여 휨강도를 증가시킨다. 본 연구에서는 기존 강도계산식에 관한 연구를 토대로 하여 비탄성 구간에 있는 변단면 I형보의 횡-비틀림 좌굴강도를 유한요소해석프로그램 ABAQUS(2007)를 이용하여 산정하고, 간편한 설계식을 제안하고 있다. 지간 한쪽 끝에 계단식 단면변화를 가지는 보에 대해서 고려하였으며, 플랜지 길이방향 비, 너비방향 비, 두께의 비로 계단식 I형보를 나타내었다. 해석에 사용된 단면매개변수는 36가지 조합이며, 비탄성 횡-비틀림 거동을 고려하기위하여 잔류응력 및 초기결함을 고려한 비선형해석을 실시하였는데, Pi(1995)등이 고려한 잔류응력의 형상과 국내 I형강 표준 치수 허용치에 근거하여 부재 길이의 0.1%를 초기제작오차로 고려하였다. 해석모델의 양쪽 끝단에는 모멘트하중을 재하하였다. 개발 제한된 식은 선형 모멘트 하중이 작용할 때 적용가능한 식으로 경제적이고 합리적인 설계에 적극 활용될 수 있을 것이다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Proceedings of Pre-symposium of the 10th ISWPC
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• pp.61-69
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• 1999

Contaminants such as fatty acids, triglycerides, resin acids and foam collected from a high yield sulfite weak liquor storage tank lowered the water surface tension and reduced inter-fibre bonding but also tended to benefit sheet opacity. Some common wet end additives such as defoamers and dispersants gave similar results. Lignosulfonate and naphthalene sulfonate showed little if any negative effect on both surface tension and sheet strength properties. Among the natural wood extractives. fatty acids were identified to be most detrimental followed by triglycerides and then resin acids. In order to alleviate the detrimental impact of these contaminants, membrane separation, air floatation and ozone treatment were carried out on paper machine white water samples. The effect of these treatments on removal of fatty and resin acids was quantified by a GC-Mass analysis. Reverse osmosis with a 1000 molecular weight cut off membrane failed to totally reject fatty and resin acids, but markedly reduced losses of sheet properties due to contaminants. Ozone treatment resulted in a significant increase of the surface tension and air floatation was considered to be a practical and useful method for removing fatty and resin acids from the machine white water.

• 한국지반공학회논문집
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• 제28권8호
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• pp.65-78
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• 2012

탄성계수값은 퇴적암의 일축압축시험을 통하여 응력수준에 따라 넓은 범위로 변하며 거동특성도 다양하게 발현되고 있다. 즉 탄성계수는 정수가 아닌 변수로 볼 수 있는 것이다. 실무에서는 참고자료 및 실험값으로 사용하고 있으나 그 값은 사용하중 수준에서는 매우 큰 값을 채용하고 있다. 설계 및 시공과정에서는 재하-재(再)재하(loading-reloading) 시험을 통한 값을 사용하여 적절하고 합리적인 결과가 도출되어야 할 것이다. 또한 사용하중의 낮은 응력수준에서 발현되는 탄성계수값의 거동특성 역시 유의하여 보아야 할 점이다.

• 한국지반신소재학회논문집
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• 제4권1호
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• pp.17-25
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• 2005

본 논문에서는 옹벽 시공 완료 후 여름철 집중강우로 인해 붕괴된 보강토 옹벽 사고사례에 대한 원인 분석을 실시하였다. 사고 원인의 명확한 규명을 위해 붕괴된 옹벽의 현장조사 및 실내시험, 현 설계법에 근거한 안정성평가, 강우의 침투해석 및 suction을 고려한 사면안정해석을 실시하였고, 그 결과 현장조건을 제대로 반영하지 못한 부적합한 설계와 불량한 뒤채움 흙의 사용, 단기간의 집중호우로 인한 suction의 감소 및 전단강도의 감소가 붕괴의 주원인인 것으로 나타났다.

• 한국과학교육학회지
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• 제32권6호
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• pp.1072-1086
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• 2012

Science, Technology, Engineering, and Mathematics (STEM) education in the U.S. has been identified as a significant national reform in K-16 education and curriculum in order to prepare students for the global economy of the 21st century. Korea has been facing very similar challenges to improve science, technology and mathematics education, in particular, the affective aspect of learning science and mathematics. Science, Technology, Engineering, Arts, and Mathematics (STEAM) education has become a crucial issue in Korean education system. The major purpose of this exploratory study is to inform the exemplary framework of STEAM education in the U.S. for Korea and to provide descriptive and analytical accounts on STEAM teaching and learning as an innovative integrated convergence education. This study integrates the outcomes of research papers on STEM education and recent literature. It employs content analysis methodology qualitatively by analyzing and synthesizing the findings, conclusions, discussions, and recommendations of accumulated research works related to STEM/STEAM education. This study will help gain a stronger sense of the STEAM framework and will guide to develop the educational programs for Korea.

• 한국간호교육학회지
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• 제16권2호
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• pp.339-346
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• 2010

Purpose: Bystander cardiopulmonary resuscitation (CPR) improves survival. However, there have been few studies on the performance of bystander CPR in Korea. This study was done to identify the reasons for being unwilling to perform CPR, and to investigate the factors associated with performing CPR on a stranger in an emergency situation. Method: The participants in this study were 444 local residents. Data were collected by using self-reported questionnaires from May 1 to June 30, 2010. For data analysis, descriptive statistics and multiple logistic regression were performed using SAS version 9.1. Result: Only 32.2% of respondents reported being willing to perform CPR on a stranger. The major reason for not being willing to perform CPR on a stranger was "have no confidence to perform CPR well". From multiple logistic regression analysis, statistically significant predictors of CPR performance on a stranger were found to be a higher educational level (OR=6.11, 95% CI 1.46-25.52), neighbors with angina pectoris or myocardial infarction (OR=6.65, 95% CI 3.93-11.24), and having confidence of performing CPR (OR=3.02, 95% CI1.78-5.14). Conclusion: CPR education (including automatic external defibrillator) should be offered to family members and neighbors. In addition, the Good Samaritan Law must be given wider publicity at the national level.

• 대한안전경영과학회지
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• 제16권4호
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• pp.215-227
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• 2014

This paper is to investigate the employees' corresponding types and casual analysis. It proposes the legal and practical measures for improvement of Industrial Accident Compensation Insurance's usability. The results from the empirical analysis indicate that (1) 91.4 percent of the respondents feel the necessity of Industrial Accident Compensation Insurance, (2) 67.4 percent of the respondents perceive that Industrial Accident Compensation Insurance is useful, (3) employers' perceptions of the specific items of Industrial Accident Compensation Insurance appears to be low. (4) 35.9 percent of the respondents deal with industrial accidents through other ways such as health insurance and car insurance. The study ends with discussion of the findings and provides several theoretical and managerial implications and recommendations for future research and applications.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.297-302
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• 2007

Recently, electrical resistivity survey is used in the various fields and applied to urban area with many electrical noises. Therefor it's necessary to observe the electrical noise effect of the geological structure. The physical scale modeling was conducted for measuring the electric noise effect of the two geological models at various distances, depths and diameters of the electric noise objects. The results are as following. 1. When conductive noise object was vertical to the strike of geological structure and moved to the strike direction, the effect of conductive noise object at various separated distances to the measurement line was disappeared at a half distance measurement line length regardless of electrode arrays. 2. When conductive noise object was vertical to the strike of geological structure and moved to the strike direction, the effect of conductive noise object at various depths was disappeared at 4unit apart from the measurement line regardless of electrode arrays. 3. When conductive noise object was vertical to the strike of geological structure and moved to the strike direction, the effect of conductive noise object at various diameters was disappeared at 4unit apart from the measurement line regardless of electrode arrays.

• 대한영양사협회학술지
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• 제9권4호
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• pp.273-277
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• 2003

The purpose of this study was to examine sanitation management practices of restaurant managers for the training needs analysis. A total of 26 restaurant managers participated in this study. A check list was consisted of three parts : facility, personal, and food hygiene. Two observers and one manager evaluated the same check list at same time and the results were compared. The results of this study suggested that most restaurants have needed for re-training programs in the view of facility, personal, food sanitation practices. Specially, proper washing and sanitizing methods for hands and utensils, proper cooking and holding temperature, and proper storing methods were needed to be trained. Based on this study, most independent restaurant managers in Cheonan were aware of training, but they had no effective training program manuals. Results of this study implicated that dietitians have new opportunity for consultants of independent restaurants in the region because they have practiced sanitation management manuals.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.105-110
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• 2011

The objective of this study is to analyze the characteristic of radiation environment in the urban and rural through the field observation in the summer. The radiation balance was compared through the measurement of the shortwave radiation and long-wave radiation in the urban, sub-urban, and rural. The following conclusion could be obtained from this research. (1) In the results of observation including the rain-day, it was found that the short wave radiance in the urban is lower about 10% than the rural. (2) The upper part of atmosphere layers in the urban area absorb much short wave radiation energies compared with the rural relatively. It can increase the temperature of the upper part of atmosphere layers and the emittance of long wave radiation. (3) The ratio of the downward short wave radiation to the downward long wave radiation was 1.24 for the urban, 1.28 for sub-urban and1.35 for rural. It can be estimated that the atmosphere condition of the rural is better than that of other areas.