• 통합자연과학논문집
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• 제10권4호
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• pp.209-215
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• 2017

CXC chemokine receptor 2 (CXCR2) is a prominent chemokine receptor on neutrophils. CXCR2 antagonist may reduce the neutrophil chemotaxis and alter the inflammatory response because the neutrophilic inflammation in the lung diseases is found to be largely regulated through CXCR2 receptor. Hence, in the present study, Topomer based Comparative Molecular Field Analysis (Topomer CoMFA) was performed on a series of CXCR2 antagonist named pyrimidine-5-carbonitrile-6-alkyl derivatives. The best Topomer COMFA model was obtained with significant cross-validated correlation coefficient ($q^2$ = 0.487) and non cross-validated correlation coefficients ($r^2$ = 0.980). The model was evaluated with six external test compounds and its $r^2{_{pred}}$ was found to be 0.616. The steric and electrostatic contribution map show that presence of bulkier and electropositive group around cyclopropyl ring may contribute more for improving the biological activities of these compounds. The generated Topomer CoMFA model could be helpful for future design of novel and structurally related CXCR2 antagonists.

• 통합자연과학논문집
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• 제10권4호
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• pp.192-196
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• 2017

Xanthine Oxidase is an enzyme, which oxidizes hypoxanthine to xanthine, and xanthine to uric acid. It is widely distributed throughout various organs including the liver, gut, lungs, kidney, heart, brain and plasma. It is involved in gout pathogenesis. Hence, in the present study, topomer based Comparative Molecular Field Analysis (topomer CoMFA) was performed on a series of Xanthine oxidase antagonist named 2-(indol-5-yl) thiazole derivatives. The best topomer CoMFA model was obtained with significant cross-validated correlation coefficient ($q^2$ = 0.572) and non cross-validated correlation coefficients ($r^2$ = 0.937). The model was evaluated with six external test compounds and its $r^2{_{pred}}$ was found to be 0.553. The steric and electrostatic contribution map show that presence of bulky and electropositive group in indole thiazole ring is necessary for improving the biological activities of the compounds. The generated topomer CoMFA model could be helpful for future design of novel and structurally related xanthine oxidase antagonists.

• Clinical Nutrition Research
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• 제12권4호
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• pp.293-303
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• 2023

Patients with chronic renal failure, many of which treated with hemodialysis, present a high prevalence of impaired muscle strength which suggest that muscle mass parameters may be used as markers for changes in muscle in these patients. Measurement of handgrip strength (HGS) is a common, simple, and quick measure of muscle function an indicator of overall muscle strength which has been associated with physical activity and several anthropometric traits. Intercellular adhesion molecule-1 (ICAM-1) and insulin-like growth factor-1 (IGF-1) are biochemical markers associated with inflammatory processes which are a common consequence of dialysis. Additionally, hemodialysis patients frequently present signs of malnutrition and depression. This cross-sectional study aimed to evaluate if muscle and biochemical markers could be used to predict the risk of depression in hemodialysis patients. Several anthropometric parameters, nutrient intake, depression state and the serum levels of ICAM-1 and IGF-1 were determined and Pearson's correlation coefficient and/or Spearman's correlation coefficient were used to test the correlation between them. Our results do not show a correlation between HGF, IGF-1 and ICAM-1 with the depression status of the patients, but mid-arm muscle circumference (MAMC) was statistically and positively correlated with depression. Additionally, ICAM-1 levels were negatively correlated with HGS, MAMC, and IGF-1. Overall, the results of the present study suggest that HGS may be used as an indicator of cardiovascular diseases and MAMC may be a good predictor of the level of depression in hemodialysis patients, although further studies are required.

• 지역사회간호학회지
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• 제12권3호
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• pp.609-619
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• 2001

This cross-sectional study is to measure the distribution of self-reported health by income, house type, level of education, income satisfaction and self reported social class in an effort to compare the level of health inequality in Korea. The data used in the research are the Social Statistics Survey undertaken in 1999. The correlation coefficient was used to measure the association between inequalities in health and inequalities in socioeconomic status. The correlation coefficient was the most significant between self-reported health and the level of education and income satisfaction. As for the health-related behavior, hypertension, smoking, overweight and drinking were shown to be highly correlated with self-reported health.

• International Journal of Computer Science & Network Security
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• 제22권10호
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• pp.11-16
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• 2022

Applying predictive analytics to predict software defects has improved the overall quality and decreased maintenance costs. Many supervised and unsupervised learning algorithms have been used for defect prediction on publicly available datasets. Most of these datasets suffer from an imbalance in the output classes. We study the impact of class imbalance in the defect datasets on the efficiency of the defect prediction model and propose a CPP method for handling imbalances in the dataset. The performance of the methods is evaluated using measures like Matthew's Correlation Coefficient (MCC), Recall, and Accuracy measures. The proposed sampling technique shows significant improvement in the efficiency of the classifier in predicting defects.

• International Journal of Air-Conditioning and Refrigeration
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• 제9권4호
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• pp.27-36
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• 2001

A new two-phase non-boiling convective heat transfer correlation for turbulent flow $(Re_{SL}>4000)$ in vertical tubes with different fluid flow patterns and fluid combinations was developed using experimental data available from the literature. The correlation presented herein originates from a careful analysis of the major non-dimensional parameters affecting two-phase heat transfer. This model takes into account the appropriate contributions of both the liquid and gas phases using the respective cross-sectional areas occupied by the two phases. A total of 255 data points from three available studies (which included the four sets of data) were used to determine the curve-fitted constants in the improved correlation. The performance of the new correlation was compared with two-phase correlations from the literature, which were developed for specific fluid combinations.

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.35.1-35.11
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• 2023

Background: Cardio-cerebrovascular diseases (CVDs) are the most common cause of death worldwide. Various CVD risk assessment tools have been developed. In South Korea, the Korea Occupational Safety & Health Agency (KOSHA) and the National Health Insurance Service (NHIS) have provided CVD risk assessments with health checkups. Since 2018, the KOSHA guide has stated that NHIS CVD risk assessment tool could be used as an alternative of KOSHA assessment tool for evaluating CVD risk of workers. The objective of this study was to determine the correlation and agreement between the KOSHA and the NHIS CVD risk assessment tools. Methods: Subjects of this study were 17,485 examinees aged 20 to 64 years who had undergone medical examinations from January 2021 to December 2021 at a general hospital. We classified subjects into low-risk, moderate-risk, high-risk, and highest-risk groups according to KOSHA and NHIS's CVD risk assessment tools. We then compared them with cross-analysis, Spearman correlation analysis, and linearly weighted kappa coefficient. Results: The correlation between KOSHA and NHIS tools was statistically significant (p-value < 0.001), with a correlation coefficient of 0.403 and a kappa coefficient of 0.203. When we compared risk group distribution using KOSHA and NHIS tools, CVD risk of 6,498 (37.1%) participants showed a concordance. Compared to the NHIS tool, the KOSHA tool classified 9,908 (56.7%) participants into a lower risk category and 1,079 (6.2%) participants into a higher risk category. Conclusions: In this study, KOSHA and NHIS tools showed a moderate correlation with a fair agreement. The NHIS tool showed a tendency to classify participants to higher CVD risk group than the KOSHA tool. To prevent CVD more effectively, a higher estimation tool among verified CVD risk assessment methods should be selected and managements such as early intervention and treatment of risk factors should be performed targeting the high-risk group.

• 한국멀티미디어학회논문지
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• 제3권6호
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• pp.604-610
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• 2000

스테레오 음향 반향 제거기는 각 채널 신호 사이의 상호상관(cross-correlation)이 크기 때문에 수신실의 반향경로를 추정하는 적 응필터 계수가 반향경로를 잘못 추정하거나 수렴이 느려진다. 본 논문에서는 스테레오 신호의 차성분(difference factor)의 절대값을 이용하여 전처리기를 구성함으로써 스테레오 신호의 상호상관을 줄여 스테레오 음향 반향 제거 성능을 향상시키는 방법을 제안한다 기존의 반파 정류 필터를 이용한 전처리기와 비교하여 제안하는 전처리기가 반향 제거 성능이 우수함을 컴퓨터 시뮬레이션을 통해서 확인한다. 그리고 전송실의 경로변화에도 성능이 저하되지 않는 것을 확인하였다.

• 한국ITS학회 논문지
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• 제13권2호
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• pp.50-56
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• 2014

본 논문에서는 LTE 700MHz(Band12, 13, 14, 17, 28, 44) 대역에서 동작 가능한 4개의 포트를 가진 펨토셀(Femtocell) MIMO 안테나를 설계 제작하였다. 마이크로스트립 패치 안테나를 기반으로 임피던스 매칭을 위하여 쇼트핀을 이용하였고, 한정된 크기에서 충분한 안테나 격리도를 얻기 위해 십자형 디커플러를 이용하였다. 시뮬레이션에 의한 최적화된 파라미터를 가지고 제작하였으며, 제작된 안테나는 VSWR${\leq}2$에서 105MHz(0.698~0.803) 대역폭을 만족하고 1.97dBi의 이득과 격리도는 13dB이상의 값을 얻었다. MIMO 안테나의 성능을 판단하는 주요 파라미터인 안테나간 상관계수는 0.2 이하의 결과를 얻었다.

• Nuclear Engineering and Technology
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• 제27권4호
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• pp.491-502
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• 1995

핵연료집합체 부수로 유동장에 대한 상세한 정보에 기초해 교차류를 정확히 예측하는 것은 핵연료의 성능을 해석하는데 중요한 요소이다. 본 연구에서는 저-Reynolds 수 k-$\varepsilon$ 난류모형을 채택하여 인접한 두 부수로 사이에 발생하는 교차류를 해석하였다 또한, 2차유동을 정확히 모사하기 위해서 비등방성 대수응력모형을 사용하였다. 이상의 난류 모형은 유한요소법을 통해 해석되었으며 가용한 실험자료와 비교하여 검증하였다. 그리고, 부수로 유동장에 대한 수치해석 결과를 이용하여 횡방향 합력손실계수의 상관식을 구성하였다. 상관식은 교차류를 제공하는 부수로의 축방향 속도에 대한 교차류의 속도비, 제공받는 부수로의 Reynolds 수 그리고 Pitch-to-diameter의 함수로 구성되었다.