http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
우리나라 대학생의 비운동성 심폐체력 추정식 개발 및 타당도 검증
이인환,한권석,송문구,강현식 대한스포츠의학회 2022 대한스포츠의학회지 Vol.40 No.1
Purpose: Non-exercise-based estimation of cardiorespiratory fitness (eCRF) is not available for Korean young adults. This study was to develop an eCRF regression equation and to validate its accuracy in Korean college students. Methods: Subjects were undergraduate students (n=1,319; female, 219) who participated in the assessment of physical fitness and risk factors at our institute. Using a random sampling method, 70% of the subjects were selected and used to develop prediction equations for estimating CRF, and 30% of the subjects were used to verify the accuracy of the equations for CRF. Body mass index (BMI), percent body fat, waist circumference (WC), physical activity, smoking, and resting heart rate were measured as covariates. CRF was assessed as minute volume of maximal oxygen consumption (VO2max) with a graded exercise test. Prediction equations for CRF were derived using stepwise linear regressions. The differences between measured and estimated VO2max values were verified by using paired t-test and Bland-Altman plots. Results: The coefficients of determination (R2) of BMI, % body fat, and WC-based regression models were 0.502, 0.514, and 0.518, respectively. The standard errors of estimate for BMI, % body fat, and WC regression models were 5.55, 5.48, and 5.46, respectively. In the validation study, no significant differences between estimated and measured VO2max values were found in BMI (p=0.971), % body fat (p=0.877), and WC (p=0.817)-based regression models. Conclusion: The current findings of the study suggest that CRF can be estimated from non-exercise healthrelated parameters with an acceptable accuracy in Korean college students.
Ellipsometry를 이용한 Low-k SiOCH 박막의 유전특성에 관한 연구
이인환,황창수,김홍배,Yi, In-Hwan,Hwang, Chang-Su,Kim, Hong-Bae 한국전기전자재료학회 2008 전기전자재료학회논문지 Vol.21 No.12
We studied the dielectric characteristics of low-k SiOCH thin films by Ellipsometry. The SiOCH thin films were prepared by deposition of BTMSM precursors on p-Si wafer by CCP-PECVD method. The nano-porous structural organic/inorganic hybrid-type of SiOCH thin films correlated directly to the formation of low dielectrics close to pore(k=1). The structural groups including highly dense pores in SiOCH thin films originated the anisotropic geometry type of network structure directing to complex refractive characteristics of SiOCH single layer on the p-Si wafer. The linearly polarized beam of Xe-ramp in the range from 190 nm to 2100 nm introduced to the surface of SiOCH thin film, and the reflected beam was Elliptically polarized by complex refractive coefficients of SiOCH dipole groups. The amplitude variation $\Psi$ and phase variation $\Delta$ of the relative reflective coefficients between perpendicular and parallel components to the incident plane were measured by Ellipsometry. The complex optical constants n and k as well as the dielectric constant and thickness of SiOCH thin films were driven by the measured value of $\Psi$ and $\Delta$.