• 대기
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• 제21권2호
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• pp.151-162
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• 2011

One-layer solar radiation(GWNU; Gangneung-Wonju National University) model is developed in order to resolve the lack of vertical observations and fast calculation with high resolution. GWNU model is based on IQBAL(Iqbal, 1983) and NREL(National Renewable Energy Laboratory) methods and corrected by precise multi-layer LBL(Line-by-line) model. Input data were used 42 atmospheric profiles from Garand et al.(2001) for calculation of global radiation by the Multi-layer and one-layer solar radiation models. GWNU model has error of about -0.10% compared with LBL model while IQBAL and NREL models have errors of about -3.92 and -2.57%, respectively. Global solar radiation was calculated by corrected GWNU solar model with satellites(MODIS, OMI and MTSAT-1R), RDPS model prediction data in Korea peninsula in 2009, and the results were compared to surface solar radiation observed by 22 KMA solar sites. All models have correlation($R^2$) of 0.91 with the observed hourly solar radiation, and root mean square errors of IQBAL, NREL and GWNU models are 69.16, 69.74 and $67.53W/m^2$, respectively.

• 천문학회보
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• 제36권2호
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• pp.74.1-74.1
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• 2011

To probe the connection between starburst and AGN activity, we investigate the relation between the 3.3 micron~PAH emission and AGN properties based on the new AKARI observations and the data collected from the literature. Using a sample of low-z Type I AGN, we measure the global 3.3 micron PAH luminosity from the AKARI slit-less spectroscopy. The 3.3 ${\backslash}$micron~PAH emissions are detected for 7 out of 26 target galaxies, but we find no strong correlation between the 3.3 ${\backslash}$micron~PAH emission and AGN luminosity, suggesting that global star formation may not be tightlyrelated with AGN activity. In contrast the to global star formation, the nuclear 3.3 micron~PAH emission luminosity, which are measured from ground-based long slit spectroscopy with a narrow slit, correlates with AGN luminosity. These results imply that starburst and AGN activity are directly connected at the nuclear region.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.232-235
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• 2011

Radiation data are the best source of information for estimating average incident radiation. Lacking this or data from nearby locations of similar climate, it is possible to use empirical relationships to estimate radiation from days of cloudiness. It is necessary to estimate the regression coefficients in order to predict the daily global radiation on a horizontal surface. There fore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for 16 different areas over Korea by estimating the regression coefficients taking into account cloud cover. Particularly, the straight line regression model proposed shows reliable results for estimating the global radiation on a horizontal surface with monthly average deviation of-0.26 to +0.53% and each station annual average deviation of -1.61 to +1.7% from measured values.

• 한국통신학회논문지
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• 제35권1C호
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• pp.123-129
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• 2010

본 논문에서는 안정된 다중경로환경에서 동기 (coherent) 단일 및 이중 이른-늦은 상관차 판별기로 범역위성항법시스템 민간용 신호의 부호동기를 결정했을 때 잔존하는 오차인 부호동기추적편이를 분석한다. 이를 위해 중심 주파수 1575.42MHz의 대표적인 위성항법신호대역에서 이진위상천이 및 이진천이반송파 변조된 민간용신호 및 그 처리과정을 모형화하고, 이 모형을 바탕으로 다양한 경우에 대해 각 부호동기추적편이를 비교 분석한다.

• Structural Engineering and Mechanics
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• 제6권3호
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• pp.259-274
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• 1998

The test results from non-destructive and destructive field testing of a three-span deteriorated reinforced concrete slab bridge are used as a vehicle to examine the reliability of available tools for finite-element analysis of in-situ structures. Issues related to geometric modeling of members and connections, material models, and failure criteria are discussed. The results indicate that current material models and failure criteria are adequate, although lack of inelastic out-of-plane shear response in most nonlinear shell elements is a major shortcoming that needs to be resolved. With proper geometric modeling, it is possible to adequately correlate the measured global, regional, and local responses at all limit states. However, modeling of less understood mechanisms, such as slab-abutment connections, may need to be finalized through a system identification technique. In absence of the experimental data necessary for this purpose, upper and lower bounds of only global responses can be computed reliably. The studies reaffirm that success of finite-element models has to be assessed collectively with reference to all responses and not just a few global measurements.

• 한국태양에너지학회 논문집
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• 제31권4호
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• pp.72-79
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• 2011

Solar radiation data are the best source of information for estimating average incident radiation. Lacking this or data from nearby locations of similar climate, it is possible to use empirical relationships to estimate radiation from days of hours of bright sunshine. It is necessary to estimate the regression coefficients in order to predict the daily global radiation on a horizontal surface. Therefore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for 16 different areas over Korea by estimating the regression coefficients taking into account hours of bright sunshine. Particularly, the proposed straight line regression model shows reliable results for estimating the global radiation on a horizontal surface with monthly average deviation of -0.2 to +0.5% and each station annual average deviation of -1.6 to +1.7% from measured values.

• Human Ecology Research
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• 제57권1호
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• pp.109-125
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• 2019

Few studies have utilized observational methods in the field of couple research even though using self-report questionnaires is prone to the subjective biases of the reporter. This study validates the Marital Interaction Coding System-Global (MICS-G), a global version of the well-established microanalytic observational coding system, Marital Interaction Coding System (MICS). Participants in the study consisted of 30 married couples with varied levels of marital adjustment who visited one of the Healthy Family and Multicultural Family Support Centers in Seoul, either for couple therapy or the "Marriage Checkup"program. Ten-minute problem-solving discussions were rated by two undergraduate student raters who were trained for 10 hours. Interobserver agreement based on percentage agreement and intraclass correlation coefficients showed a high level of agreement between raters in establishing interrater reliability. Convergent validity was established by: correlations among marital adjustment, psychological aggression, mental health, and MICS-G categories of conflicts, validation, invalidation, facilitation, and withdrawal. MICS-G categories also were successful in discriminating between distressed and nondistressed couples, which provides evidence of discriminant validity for MICS-G. This study showed that MICS-G is a promising method for researchers to observe couple interactions in a more cost-effective way. Methodological issues and practical applications are also discussed.

• Educational Technology International
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• 제19권1호
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• pp.93-122
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• 2018

It is crucial to understand the characteristics of learner questioning due to the effects it has on learning. This study focuses on the effects of middle school students questioning on their academic achievement in an online inquiry learning environment. A survey of 827 middle school students was conducted; the students took part in an online math and science program offered by a center for the gifted. Throughout the survey, learner questioning was analyzed, and its correlation with academic achievement was investigated. An analysis was based on questioning categories of a low- and high-level questions from previous studies. Through the survey, it was found that the number of learner questions asked in the online environment was small, but the number of low- and high-level questions were almost equal. Secondly, the higher the academic achievement level of the student, the higher the possibility they would ask either low- or high-level questions. Lastly the group of students in both low- and high-levels of questioning earned the highest average scores on formative evaluations and inquiry tasks. This indicates that regardless of the level of questions, the act of questioning itself is highly related to the academic achievement. However, in the case of advanced learning projects, the quality of questioning and high-level questioning affected the academic achievement of students. Based on these results, implications for the encouragement of learner questioning and support for asking high-level question are suggested.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.483-486
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• 1999

A series of dynamic and static tests were conducted to observe the actual responses of a 1:5 scale 3-story reinforced concrete (RC) frame which was designed only for gravity loads. One of the major objectives of these experiments are to provide the calibration to the available static and dynamic inelastic techniques. In this study, the experimental results were simulated by using a nonlinear analysis program for reinforced concrete frame, IDARC-2D. The evaluation of the degree of the simulation leads to the conclusion that while the global behaviors such as story drifts and shears can be in general simulated with the limited accuracy in the dynamic nonlinear analysis, it is rather easy and simple to get the fairly high level of accuracy in the prediction of global and local behaviors in the static nonlinear analysis by using IDARC-2D.

• 태양에너지
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• 제9권3호
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• pp.25-36
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• 1989

It is necessary to estimate the regression coefficients in order to predict the monthly mean daily global radiation on a horizontal surface. Therefore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for any area over Korea by estimating the regression coefficients taking into account latitude, percentage of possible sunshine, and cloud cover. Particularly, the single linear equation proposed by Page & Garg shows reliable results for estimating the global radiation with average deviation of -1 to 3% from the measured values.