• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.1
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• pp.56-69
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• 2012

Objectives: This study was conducted to investigate the relationship between menstrual conditions and items of health checkup examinations in female university students for prediction of reproductive health. Methods: Data from the 2011's medical examination participants(990 students among total 1,699 students) of ${\bigcirc}{\bigcirc}$ University University in Korea were analyzed for this study. Menstrual condition, Sa-sang constitution and other surveys were checked through self-administered questionnaire, health checkup were measured anthropometric variables, CBC, B/C and U/A. Results: In the 46.4% of total participants appeared menstrual disorder of menstrual cycle or menstrual amount, the irregular period of menstrual cycle have a influence on menstrual amount. stress was relatively heavy factor of causing irregularity of menstrual cycle and amount, RBC, cholesterol, ABO type and Sa-sang constitution had some connection with menstrual amount. Conclusions: Among the items of health checkup examinations, stress, RBC, cholesterol, ABO type and Sa-sang constitution were related with the change of menstrual cycle and amount.

• Journal of the Korean Society for Heat Treatment
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• v.31 no.6
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• pp.300-306
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• 2018

In the present study we proposed new equations to predict the liquidus temperature curve for hypoeutectic Al-Si-Cu-Mg alloy. A thermodynamic simulation was carried out to calculate the liquidus temperature, eutectic temperature and eutectic Si concentration with different Si, Cu, and Mg contents in hypoeutectic Al-Si alloys. Regressed equations were derived using the thermodynamic simulation results by multiple regression analysis. The proposed equations were compared with the equations reported previously by other researchers and agreed better with the experimental data. The addition of Cu and Mg lowered the eutectic temperature. The eutectic Si concentration was decreased by adding Cu whereas that was increased by adding Mg. Al-Si binary phase diagram was successfully predicted with a consideration of the effect of Cu and Mg addition by using the proposed equations.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.513-525
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• 2020

Purpose: The purpose of this study is to analyze the characteristics of local factors affecting number of tuberculosis death by urban and rural areas. Method: The Partial Least Square(PLS) Regression analysis was used to solve the problem of multicollinearity and number of samples. Result: As a result of analysis, The number of tuberculosis deaths in urban and rural areas is about three times as large. As a result of analysis about Regional Characteristics Factor, In general, children, elderly people, and economically vulnerable populations are more likely to be exposed to tuberculosis. In differential results, it shows that environmental factors such as ultrafine dust and sulfur dioxide have a significant impact on the number of tuberculosis deaths in urban areas and social factors such as depression experience rate in rural areas. Conclusion: The Tuberculosis prevention and management policies that reflect the characteristics of urban and rural areas are needed in the future.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.130-140
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• 2009

Raising the competitive power of the enterprise to recently, all resources integration it is a tendency which it manages with the method for, the reasoning being caused by system is professionalized and chief executive officer complicated becoming gets off the decision-making being difficult, it is following. The management technique which is BPR with solution plan will be presented, it will reach and ERP systems which it comes true concretely appeared. From the research which it sees in order to apply at the governmental under the influence public enterprise as ERP systems which it develops it provided ERP information to the customer at real-time and the web environmental ERP system from business site it will be able to control a company internal business at real-time it constructed. The evaluation which is fixed quantity it led in about the system which is constructed and improvement and expense curtailment of solution and business productivity of customer dissatisfaction, the system effectiveness and customer satisfaction index etc. improving, it verified.

• Composites Research
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• v.28 no.5
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• pp.265-269
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• 2015

Development of simple and efficient method for large-scale production of mechanically strong and electrically conductive graphene fiber is highly desirable for practical applications, such as fiber-reinforced composites, wearable electronics, and electromagnetic irradiation shielding. Here, we present a facile approach for the preparation of amine-functionalized graphene fibers by simple wet-spinning of diamine-functionalized graphene oxide (GO-$NH_2$), which is used because of its synthetic convenience, good dispersity, and scalable production with low cost. The amine-functionalized graphene fiber shows high electrical and mechanical properties compared to pristine graphene oxide fiber due to the electrostatic interaction between amine groups and electronegative functional groups of graphene oxide.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.1
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• pp.70-78
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• 2012

Objectives: The purpose of this article is not until to investigate the changes and types of statistical methods and to point out the statistical errors after analyzing the method of articles that improve the quality of the statistical analysis of papers published in the Journal of Oriental Obstetrics and Gynecology. Methods: Papers published in the Journal of Oriental Obstetrics and Gynecology from 2009 to 2011 were reviewed for methodological and statistical validity using a modified version of Ahn's checklist. A statistician reviewed individual papers and evaluated the list items in the checklist for each paper. To avoid the potential assessment error by the statistician who lacks expertise in the field of Oriental Obstetrics and Gynecology. Results: A total of 190 papers including 64 original articles, 40 reviews article, 58 case report and 28 brief communication were reviewed. Statistics methods used in 121 papers were composed of t-test(58.7%), ANOVA test(19.8%) and ${\chi}^2$- test (14.0%) et al. Whereas only 14.9% of papers were free of statistical errors, the number of omission errors was 58 and the number of commission errors was 149 each. Conclusions: A variety of statistical errors were encountered in papers published in the Journal of Oriental Obstetrics and Gynecology. Accordingly, researchers should be more careful when it comes to describing and applying statistical methods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.508-516
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• 2021

Although scientist have been reporting recently that changes in ocean environment influence the species composition, movements, and growth of fish in Korea waters. Previous studies on fish vulnerability owing to climate changes are insufficient to explain the effect of fluctuating ocean environments on fisheries ground. In this study, we suggested a method for the assessment of fisheries sensitivity to various factors in ocean environments in Korean waters. To evaluate the fisheries sensitivity, catch data (Chub mackerel, Hairtail, Common squid, small yellow croaker) from National federation of fisheries cooperatives in Korea (1991-2017) and oceanographic data from Korea Ocean Data Center (KODC; 1960-2017) were normalized using the z-score method. Thereafter, the fisheries sensitivity was calculated using the difference between the catch data and the oceanographic data. Finally, the fisheries sensitivity was evaluated based on evaluation grade ratings. Result revealed that in the south sea, variability in catch data was obviously higher than environmental fluctuation (evaluation grade 1), indicating that catch variability in response to environmental change is most sensitive in the south sea among Korean waters in 2017. These results would be helpful for fishery management and policy for sustainable yield in Korean waters.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.860-865
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• 2012

Although biomass syngas is very low calorific gas, it is utilized by means of dual fuel combustion technology in the fields of industrial furnace and boiler as a substitute oil technology. The basic structure of duel fuel combustion burner is designed so that low caloric gas fuel is supplied around an oil burner in the middle. In the present study, three types of mixing burners were manufactured to conduct performance experiment. Low caloric gas was evenly distributed around the oil burner and the method of changing the angle of gas nozzle was applied. CO generation decreased according to the increase of the amount of air for combustion. In addition, the shapes and colors of flame changed according to the proportions of gas and oil used. Remained flame after combustion was from the lack of atomization at the exit of oil burner. Although it was difficult to maintain the optimum air ratio due to different required air ratio for oil and syngas, stable combustion was able to maintained within excess oxygen concentration of 4.7~8.2%. From this study, it was shown that the oil atomization at the exit of fuel oil nozzle was promoted by the increased rate of syngas combustion and the CO concentration in flue gas lower than only fuel oil combustion.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.106.2-106.2
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• 2010

동식물성 기름과 메탄올의 전이에스테르화 반응에 의해 생산되는 바이오디젤은 환경친화성과 지속가능성이 인정됨에 따라 그 생산량이 급격히 증가하고 있어 대두유, 유채유, 팜유 등의 원료유 부족과 가격 상승, 수급 불안정 등의 문제가 대두되고 있다. 이를 해결하기 위한 방안으로 유리지방산 함량이 높은 저가유지 자원(폐식용유, 폐돈지, 폐우지, soapstock, trapped grease)과 새로운 오일 작물을 이용한 생산 기술 연구가 활발히 진행되고 있다. 본 연구에서는 비활용 해외 열대작물 씨앗에서 착유한 식물성 오일을 정제하여 바이오디젤 원료유를 생산하는 과정에서 발생하는 폐기물(폐유, 폐수)의 경제적 처리 방안으로 유화유 제조 원료(벙커C유, 물)와 유화유 제조 첨가제(무기계, 유기계)로 활용 가능성을 검토하였다. 열대작물 오일의 물성 분석 결과 고형물, 수분, 인지질(phospholipid), 유리지방산(free fatty acid) 함량이 기존 원료유보다 매우 높게 나타났다. 인지질은 바이오디젤 제조 반응후 에스테르와 글리세린의 층분리를 방해하고 유리지방산은 염기촉매와 결합하여 지방산염을 생성해 생산 수율을 감소시킨다. 고형물과 수분 역시 촉매반응에 악영향을 가지나 여과와 감압증발에 의해 쉽게 제거가 가능하다. 유리지방산은 산촉매 에스테르화 반응에 의해 제거가 가능하다. 인지질은 탈검(degumming) 과정을 통해 제거하며 탈검은 수용성 탈검, 산 탈검, 세정 공정으로 구성된다. 착유한 원료유의 고형물을 제거 후 물과 수세하여 수용성 인지질을 수화하여 층 분리해 제거하고 상층의 오일은 추가적인 산 탈검을 수행한다. 그 뒤 세정을 통해 사용된 탈검제인 산과 추가적으로 수화된 인지질을 제거하게 된다. 이러한 3단계의 탈검 과정에서 하층으로 오일과 물이 폐기물로서 배출되며 본 연구에서는 배출 폐기물을 다시 층분리하여 오일층과 물 층으로 구분하여 유화유 제조에 사용되는 벙커C유, 물, 그리고 기존 유기계 및 무기계 유화제의 대체 가능성을 조사하였다. 유화 연료유는 기름과 물을 균일한 분산상으로 혼합한 연료유로 연소시 오일계 성분의 미연분을 감소시켜 연료 효율 제고와 배출가스 성상을 개선하기 위해 개발되어 왔다. 본 발표에서는 다양한 종류의 상용 첨가제 및 바이오디젤 원료유 생산 폐기물을 활용해 유화 연료유를 제조하였으며 각 유화유의 장시간의 상(phase) 안정성을 비교하였다. 바이오 폐기물 중에는 천연 계면활성제(surfactant)인 인지질이 다량 함유되어 있어 기존의 무기계 및 유기계 유화제보다 상 안정성이 우수하게 나타났으며 바이오디젤 원료유 생산 공정의 폐기물인 폐유과 폐수의 활용이 가능한 것으로 나타났다.

• Progress in Medical Physics
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• v.11 no.1
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• pp.1-18
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• 2000

For wedged photon beams, the variation of the wedge factor with field size was reported by several authors. However, until now such variation with field size had not been explained quantitatively. Therefore, the variation of the wedge factor was investigated by measuring outputs with field sizes increasing from 4 cm $\times$ 4 cm to 25 cm $\times$ 25 cm for open and wedged 6 and 10MV X-ray beams. The relative outputs for wedged fields to 10 cm $\times$ 10 cm have been obtained. The results show the Increase of the wedge factor caused by the change in fluence of high energy Photon beam with field size, up to 8.0% for KD77-6MV X-ray beam. This increase could be explained as a linear function of the irradiated wedge volume except small field size up to about 10 cm. In the cases of the narrow rectangular beam parallel to the wedge direction, the wedge factor decreases slightly with increasing field size up to about 10-15 cm due to a relatively reduced photon fluence from the change of the wedge thickness. We could explain the causes of a wedge factor variation with field size as the fluences of primary photon passed throughout the wedge, contributing to the dose at the central beam axis and that the fluences were affected by the gradient of the wedge with the change of field size. For clinical use, the formula developed to describe the wedge factor variation with field size has been corrected.