• Structural Engineering and Mechanics
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• 제68권3호
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• pp.299-312
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• 2018

In this paper, an extended finite element method is proposed to analyze both geometric and material non-linear behavior of general Functionally Graded Material (FGM) plate-shell type structures. A user defined subroutine (UMAT) is developed and implemented in Abaqus/Standard to study the elastoplastic behavior of the ceramic particle-reinforced metal-matrix FGM plates-shells. The standard quadrilateral 4-nodes shell element with three rotational and three translational degrees of freedom per node, S4, is extended in the present study, to deal with elasto-plastic analysis of geometrically non-linear FGM plate-shell structures. The elastoplastic material properties are assumed to vary smoothly through the thickness of the plate-shell type structures. The nonlinear approach is based on Mori-Tanaka model to underline micromechanics and locally determine the effective FGM properties and self-consistent method of Suquet for the homogenization of the stress-field. The elasto-plastic behavior of the ceramic/metal FGM is assumed to follow Ludwik hardening law. An incremental formulation of the elasto-plastic constitutive relation is developed to predict the tangent operator. In order to to highlight the effectiveness and the accuracy of the present finite element procedure, numerical examples of geometrically non-linear elastoplastic functionally graded plates and shells are presented. The effects of the geometrical parameters and the volume fraction index on nonlinear responses are performed.

• 한국산학기술학회논문지
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• 제14권8호
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• pp.3897-3906
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• 2013

본 연구의 목적은 임신 여성을 대상으로 산전우울의 발생 정도와 이와 관련된 영향요인을 파악하기 위함이다. D광역시 소재 종합병원 및 산부인과 병원 외래를 방문하거나 원내 특강을 받는 160명의 임부를 연구대상으로 하였으며, 우울을 측정하기 위한 도구로 한국형 EPDS(Edinburgh Postnatal Depression Scale)를 사용하였다. 자료분석은 서술적 통계, t-test, ANOVA, Pearson's correlation coefficients와 stepwise multiple regression을 사용하였다. 연구결과, 임신 여성의 우울점수는 평균 $7.80{\pm}4.86$점(0-30점)이었으며, 대상자의 56.3%가 정상(0-8점), 23.1%가 경계선(9-12점), 20.6%는 심각한 수준(13점 이상)인 것으로 나타났다. 임신 여성의 산전우울 영향요인으로는 주관적 건강상태, 임부스트레스, 자아존중감 순이었으며, 이 변수들은 산전우울을 36.7% 설명하는 것으로 나타났다. 따라서 산전우울을 예방하기 위해 이러한 변수들이 충분히 고려되어야 할 것으로 생각된다.

• 대한간호학회지
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• 제47권1호
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• pp.133-141
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• 2017

Purpose: The aim of this study was to identify the relationship between awareness of nutrition labeling and menstrual cycle irregularity in women from a nationally representative sample of the Korean population. Methods: A cross-sectional analysis was performed using hierarchical multi-variable logistic regression analysis models. A total of 4,324 women aged 19~54 years from the 2010~2012 Korean National Health and Nutrition Examination Survey participated in the study. The participants were classified into three groups based on self-report responses to a questionnaire about their awareness of nutrition labels: Reading, Not-Reading, and Not-Knowing Groups. Results: The Reading, Not-Reading, and Not-Knowing Groups comprised 46.4%, 44.9%, and 8.7% of the participants, respectively, and 53.6% of the participants had never used nutrition labels. In the Not-Knowing Group, irregular menstrual cycles for more than 3 months were significantly more common than women with irregular menstrual cycles for up to 3 months and women with regular menstrual cycles. Women in the Not-Knowing Group were more likely to exhibit menstrual cycle irregularity (adjusted odds ratio: 1.63, 95% confidence interval: 1.10~2.41) compared to women in the Reading Group after adjusting for age, body mass index, smoking status, alcohol intake, exercise regularity, stress, depression, suicidal ideation, metabolic syndrome, age at menarche, parity, and use of oral contraceptives. Conclusion: No awareness of nutrition labeling appears to be associated with a higher prevalence of menstrual cycle irregularity in a nationally representative group of Korean women.

• 한국전산구조공학회논문집
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• 제29권3호
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• pp.237-244
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• 2016

본 연구는 재료비선형 문제를 다루기 위한 비선형 MLS 차분법의 정식화 과정을 제시한다. MLS 차분법은 절점모델을 기반으로 고속 미분근사식을 활용하여 지배 미분방정식을 직접 이산화 하는데, 변수를 변위로 일원화한 Navier 방정식을 사용하여 탄성재료 문제를 다룬 기존의 MLS 차분법은 재료의 구성방정식을 별도로 고려할 수 없다. 본 연구에서는 비선형 재료의 구성방정식을 반영할 수 있는 강정식화를 위해 1차 미분근사를 반복 사용하는 겹미분근사를 고안했다. 응력의 발산으로 표현되는 평형방정식을 그대로 이산화하고 Newton 방법을 적용하여 반복계산을 통해 수렴해를 찾는 비선형 알고리즘을 제시했다. 응력 계산과 내부변수의 갱신은 return mapping 알고리즘을 활용하였고, 알고리즘 접선계수(algorithmic tangent modulus)의 적용을 통해 빠르고 안정적인 반복계산이 가능하도록 하였다. 재생성 시험을 통해 겹미분근사의 정당성을 검증했고, 비선형재료에 대한 인장문제의 해석을 통해 개발된 비선형 MLS 차분 알고리즘의 정확성과 안정성을 확인하였다.

• 중환자간호학회지
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• 제11권2호
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• pp.75-85
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• 2018

Purpose : The purpose of this study was to examine the possible direction of critical care nursing research in the future by analyzing the trends of recent Korean studies. Method : Using a database search, we selected 263 articles on critical care nursing that were published in Korean journals between 2008 and 2017. Then, we conducted an integrative review of the contents of the selected articles and analyzed the English abstracts using the relevant packages and functions of the R program. Results : The number of studies concerning critical care nursing has increased over the 10-year period, and the specific topic of each study has diversified according to the time at which it was conducted. In terms of quality, the majority of the research was published in high-level academic journals. The key words regularly studied over the past decade were: knowledge, delirium, education, restraint, stress, and infection. Studies related to vancomycin-resistant enterococci infection, compliance, and standards have decreased, while studies related to death, communication, and safety have increased. Conclusion : Randomized controlled trials and protocol research for evidence-based critical care need to be conducted, as does research on family involvement. The key word analysis of unstructured text used in this study is a relatively new method; it is suggested that this method be applied to various critical care nursing research and develop it methodologically.

• Nuclear Medicine and Molecular Imaging
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• 제43권3호
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• pp.159-164
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• 2009

Coronary artery disease is on the rise over the world. Myocardial perfusion SPECT is a well established technique to detect coronary artery disease and to assess left ventricular function. In addition, it has the unique ability to predict the prognosis of the patients. Moreover, the application of ECC-gated images provided the quantitatve data and improved the accuracy. This approach has been proved to be cost-effective and suitable for the emerging economies as well as developed countries. However, the utilization of nuclear cardiology procedures vary widely considering the different countries and region of the world. Korea exits 2-3 times less utilization than Japan, and 20 times than the United States. Recently, with the emerging of new technology, namely cardiac CT, cardiac MR and stress echocardiography, the clinical usefulness of nuclear cardiology has been called in question and its role has been redefined. For the proper promotion of nuclear cardiology, special educations should be conducted since the nuclear cardiology has the contact points between nuclear medicine and cardiology. Several innovations are in horizon which will impact the diagnostic accuracy as well as imaging time and cost savings. Development of new tracers, gamma camera technology and hybrid systems will open the new avenue in cardiac imaging. The future of nuclear cardiology based on molecular imaging is very exciting. The newly defined biologic targets involving atherosclerosis and vascular vulnerability will allow the answers for the key clinical questions. Hybrid techniques including SPECT/CT indicate the direction in which clinical nuclear cardiology may be headed in the immediate future. To what extent nuclear cardiology will be passively absorbed by other modalities, or will actively incorporate other modalities, is up to the present and next generation of nuclear cardiologists.

• 한국식품저장유통학회지
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• 제13권4호
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• pp.495-500
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• 2006

항산화물에 의한 천식 억제 효과를 확인하기 위하여 항산화정도를 알아볼 수 있는 DPPH, FRAP, hydroxyl radical 소거활성 실험을 high throughput-compatible chemical assay로 디자인하여 해바라기씨 추출물에 적용하여 보았다. 해바라기씨 추출물의 용매에 따른 항산화 효과 중 $H_2O_2$에 의한 산화스트레스에 의한 세포사멸을 DW추출물에서 강한 억제능력을 보였다. 이를 이용하여 마우스를 이용한 천식 동물모델에 적용하여 탁월한 천식 억제효과를 $CD4^+$세포, IL-4와 IL-13의 발현정도를 통해 알수 있었다. 해바라기씨 추출물은 천식에 탁월한 효과가 있는 것으로 in vitro 및 in vivo 실험으로 증명하였다.

• 지역사회간호학회지
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• 제17권2호
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• pp.210-222
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• 2006

Purpose: This study was performed to identify the health status, healthy behavior, and health promotion program needs of day time and shift time industrial male workers at an workplace. Method: Relevant data were collected from June 20 to August 18, 2005. Questionaries were distributed to all subjects along with their medical records of 2005 and 151 sets of responses were used for the analysis. Collected data were analyzed using SPSS WIN 10.0. Result: 1. Health Status - day time and shift-time workers had significant differences in obesity ($x^2=8.38$, p<.01) and blood pressure ($x^2=-2.17$, p<.05). 2. Healthy Habits - Full-time and part-time workers had significant differences in regular meals (63.83, p<.01), preferred foods ($x^2=7.10$, p<.05), and sleep time (t=-3.55, p<.01). They also had significant differences in exercising ($x^2=13.11$, p<.01), exercising time (minutes) (t=-2.25, p<.01), and use of fitness centers ($x^2=7.02$, p<.05). 3. They also had significant differences in their needs of health programs ($x^2=8.66$, p<.01). Conclusion: This study revealed that day time and shift-time workers had differences in obesity and blood pressure, as well as differences in eating sleeping, and exercising patterns. Both groups needed 'fitness programs' more than any other types of health programs and picked 'weight loss' and 'stress control' programs for other options. Industrial nurses should be able to create appropriate health programs for each group based on the above results and induce the workers' active participation.

• 한국산학기술학회논문지
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• 제21권9호
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• pp.414-423
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• 2020

최근 콘크리트 구조물을 보강하는데 경량이며 높은 강도를 가지고 있는 FRP(Fiber Reinforced Polymer)시트의 사용이 증가하고 있는데 구조물 보강 설계 시 부착 강도가 매우 중요하다. 그래서 FRP시트와 콘크리트 사이의 부착 강도에 대한 정확한 수치 모델을 얻기 위하여 많은 연구자가 다양한 변수(콘크리트 압축강도 및 인장강도, 콘크리트와 FRP의 탄성계수, 콘크리트와 FRP의 폭과 두께, 파괴에너지, 부착 길이, 유효부착길이, 최대 부착 응력과 최대 슬립)를 가지고 실험과 해석 연구를 수행하여 왔다. 결과적으로 많은 모델이 도출되었으나 실무에 쉽게 사용될 수 있는 검증된 모델은 제시되지 않았다. 그래서 본 연구는 현재까지 제안된 23개의 모델(Khalifa 모델, Iso 모델, Maeda 모델, Chen 모델 등)로부터 부착 강도에 미치는 요인을 분석하고 188개의 시험체에 대한 부착 강도 실험값을 각 모델들의 수치 결과 값과 비교하여 수식이 간단하고 높은 정도를 가진 사용하기 쉬운 모델을 제시하고자 하였다. 결과적으로 부착 강도 모델로 Iso 모델과 Holzenkӓmpfer 모델의 유효부착길이에 근거한 실용성 있는 모델을 제안하였다.

• 대한의용생체공학회:의공학회지
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• 제11권2호
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• pp.305-314
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• 1990

In this paper we have implemented and tested TPN which is system to supply sufficent nutrition to nutritionally deficient patient by means of ES (expert system) a kind of A.1 (artificial intelligence) . This system affords to evaluation of nutritional state of patient which is essential to physi- cian. who performs TPN, decision of performing TPN and management of patient-data & calculation of information needing to making TPN fluid. The features were as follolv 1. we input data, take ideal weight of patient and 24hr's creatlnln In urine according to chart in system compare TSF (triceps skin fold), MAC (mid-arm circumference), AMC (arm muscle circumference) to 5th, 15th, 50th percentile and evaluate the nutritional state of patient. 2. Calculation of protein & nonprotein calorie needing to treament of patient can be made exactly by stress factor, activity factor and body temperature. 3. patient's personal recording needing to management of patient date name of chief doc- tor, name of department of admission, chart number, history can by taken very easily. 4. The way of system operating is pull-down Menu one, It can be processing very efficiently. 5. Date processing in system, we can manage memory volume of computer verlr efficiently using of dynamic allocation variables. 6. We can make it very easy to edit & revise the input data, processed data is saved to diskette in 2 files (TDF, THF) , these are semipermanent preservation.