• 한국의류학회지
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• 제23권5호
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• pp.745-756
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• 1999

The purpose of this study is to investigate the characteristics of the clothing consumption expenditures by the business cycles in Korea during the period of first quarter of 1979 to second quarter of 1998. Business cycles were examined using data GNP from the National Accounts published by the Bank of Korea and clothing expenditures from the monthly statistics of Korea published by the National Statistical Office of Korea. Data were analyzed by regression analysis standard deviation sample cross-correlation coefficient and skewness statistics. The main results are as follows. 1. During the period of 1979.I-1998.II GNP and per-person consumption expenditures for clothing and shoes have continuously increased except during 1980 and the recent depression of the national economy. Clothing expenditures dropped severely during the two recent depression of the national economy. Clothing expenditure dropped severely during the two depression periods. Clothing expenditures were the highest in the fourth quarter and the lowest in the third quarter of the year. 2. According to the results of the regression analysis the business cycles had a significant influence on the clothing expenditures. the volatility of the clothing expenditure was 2.60 times higher than that of the business cycles. 3. Clothing expenditures displayed procyclical fluctuation and coincident movement to the business cycles. Also clothing expenditures showed an unsymmetric behavior over the expansion phases and contraction phases of the business cycles. That is the clothing expenditures increased slowly in the expansion phases and decreased quickly and severely in the contraction phases of the business cycles.

• 한국농공학회지
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• 제41권3호
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• pp.41-50
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• 1999

Derivatio of reasonable design floods was attempted by comparative analysis of design floods derived by Generalized Extreme Value(GEV) distribution using methods of L-moments and LH-moments for the annual maximum series at ten watersheds along Han, Nagdong. Geum, Yeongsan and Seomjin river systems, LH-coefficient of variation, LH-skewness and Lh-kurtosis were calcualted by KH-moment ration respectively. Paramenters were estimated by the Method of LH-Moments, Design floods obtained by Method of LH-Moments using different methods for plotting positionsi n GEV distribution and design floods were compared with those obtained using the Method of L-Moments by the Relative Mean Errors(RME) and Relative Absolute Errors(RAE). The results was found that design floods derived by the method of L-Moments and LH-Moments using Cunnane plotting position formula in the GEV distribution are much closer to those of the observed data in comparison with those obtained by methods of L-moments and LH-moments using the other formula for plotting positions from the viewpoint of Relative Mean Errors and Relative Absolute Errors. In viewpoint of the fact that hydrqulic structures including dams and levees are genrally using design floods with the return period of two hundred years or so, design floods derived by LH-Moments are seemed to be more reasonable than those of L-Moments in the GEV distribution.

• 유통과학연구
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• 제19권1호
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• pp.27-35
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• 2021

Purpose: This study is to investigate the effect of managerial ownership level in distribution and service companies on the stock price crash. The managerial ownership level affects the firm's information disclosure policy. If managers conceal or withholds business-related unfavorable factors over a long period, the firm's stock price is likely to plummet. In a similar vein, management's equity affects information opacity, and information asymmetry affects stock price collapse. Research design, data, and methodology: A regression analysis is conducted using the data on companies listed on the Korea Composite Stock Price Index (KOSPI) between 2012-2017 to examine the effect of the managerial ownership level on stock price crash risks. Results: Logistic and regression results indicate that the stock price crash risk was reduced as managerial ownership levels are increased. The managerial ownership level has a significant negative coefficient on stock price crash risk, negative conditional return skewness of firm-specific weekly return distribution, and asymmetric volatility between positive and negative price-to-earnings ratios. Conclusions: As the ownership and management align, the likeliness of withholding business-related information is reduced. This study's results imply that the stock price crash risk reduces as the managerial ownership level increases because shareholder and manager interests coincide, thereby reducing information asymmetry.

• 한국과학교육학회지
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• 제41권6호
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• pp.533-542
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• 2021

이 연구의 목적은 고등학생의 기후변화 대응 실천역량을 진단하는 검사도구를 개발하는 데 있다. 내용타당도 검증과 두 차례의 조사를 바탕으로 검사도구를 개발하였고, 본조사는 전국의 고등학생 1~2학년 528명을 대상으로 실시하였다. 기후변화 대응 실천역량 검사도구의 신뢰도와 타당도를 확보하기 위해 문항 분석(평균, 왜도, 첨도, 문항-전체 상관), 신뢰도 분석, 확인적 요인분석을 활용하였다. 기후변화 대응 실천역량 검사도구는 7가지 영역의 총 35개 문항으로 구성되어 있으며, 검사에 소요되는 시간은 약 15분 내외이다. 이 검사도구의 영역별 구성은 기후변화 관련 지식, 기후변화 감수성, 성찰능력, 통합적 사고, 의사소통능력, 의사결정능력, 실천 의지이다. 이 검사도구는 자기보고식의 5점 리커트 척도(1=전혀 그렇지 않다, 2=그렇지 않다, 3=보통이다, 4=그렇다, 5=매우 그렇다)로 응답하도록 되어있으며, Cronbach-α 값은 전체 0.953, 하위요소의 경우 0.786~0.862의 범위로 나타났다.

• 한국해안해양공학회지
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• 제18권2호
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• pp.112-123
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• 2006

우리나라 연안 비조석 성분자료의 확률밀도함수 형태로 쌍봉형 정규분포 함수 형태를 제안하였다. 비조석 성분 자료는 국립해양조사원에서 제공하는 인천, 군산, 목포, 제주, 여수, 마산, 가덕도, 부산, 포항, 속초 검조소의 1시간 간격 조위자료에서 64개 분조성분을 이용하여 합성된 성분을 제외한 잔차성분이다. 제안된 분포함수와 비조석 성분자료 분포함수의 RMS 오차 및 결정계수(R2) 값을 비교·분석한 결과, 비조석 성분자료의 확률밀 도함수로 본 연구에서 제안한 쌍봉형 함수가 기존에 사용하던 정규분포형 함수보다 더 적합한 함수로 파악되었다. 본 연구에서 제안된 확률밀도함수의 매개변수는 Newton 방법을 수정한 Levenberg-Marquardt 방법으로 추정 하였으며, 비조석 성분 자료의 표준편차 및 왜곡도 계수는 목포, 제주, 속초 지점을 제외하고는 분석지점 검조소 자료의 비조화 상수와 밀접한 관계가 있는 것으로 파악되었다.

• 대한영상의학회지
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• 제83권1호
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• pp.112-126
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• 2022

목적 연조직 육종의 종양 가장자리 침윤을 예측하기 위한 3T 자기공명영상 텍스처 분석의 가치를 규명한다. 대상과 방법 3T 자기공명영상을 시행하고, 병리학적으로 연조직 육종으로 확인된 31명의 환자를 대상으로 하고, 병리학적인 가장자리 침윤을 표준으로 사용하였다. 연조직 육종에 대한 텍스처 분석은 축상 T1 강조영상, T2 강조영상, 지방억제 조영증강 T1 강조영상, 확산강조영상(b = 800 sec/mm²) 및 현성확산계수 지도 영상에서 이루어졌다. 텍스처 분석에서 얻어진 정량적 변수가 침윤성(infiltrative) 육종과 국한성(circumscribed) 육종에서 차이가 있는지 비교하였다. 결과 총 23명의 연조직 육종에서 병리학적인 가장자리 침윤을 보였다. 침윤성 육종과 국한성 육종은, T1 강조영상 공간 스케일 인자(spatial scaling factor; 이하 SSF) 0, 6에서의 첨도(kurtosis), 조영증강 T1 강조영상(SSF, 0)에서의 첨도, 확산강조영상(SSF, 0)에서의 왜도(skewness), 현성확산계수 지도(SSF 2, 4)에서의 왜도에서 유의한 차이가 있었다(p ≤ 0.046). 자기공명영상 텍스처 소견을 이용한 종양 가장자리 침윤을 예측하는 정확도는 수신자운영특성곡선(receiver operating characteristic; 이하 ROC)의 곡선하 면적(area under the ROC curve) 0.951 (p < 0.001)이었다. 결론 자기공명영상 텍스처 분석은 연조직 육종의 침윤성 가장자리를 예측하는 데 있어 신뢰 할 수 있으며 정확하다.

• 대기
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• 제24권3호
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• pp.317-329
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• 2014

Eddy covariance data have been analyzed to investigate the influence of surface heterogeneity on turbulent transfer over farmland and industrial sites near Nakdong river, Korea, where both large and small scale heterogeneities co-exist. For this purpose, basic turbulent statistics, quadrant analysis and multi-resolution decomposition have been analyzed during the daytime. Basic turbulent statistics were compared with typical turbulent statistics in the surface layer. Such comparisons were in close agreement for momentum and heat at both sites but not for water vapor at industrial site. The correlation coefficient between water vapor and vertical velocity ($r_{wq}$) is relatively low and skewness of water vapor ($sk_q$) is very low at industrial site, possibly due to limited water source. For heat at both sites and water vapor at farmland, the quadrant analysis show similar behavior to that over homogeneous site but for water vapor at industrial site, the presence of river and limited water source at industrial site seems to influence on water vapor transfer by coherent eddy motion by increasing sweep contribution and decreasing ejection contribution. Multi-resolution decomposition analysis shows that large scale heterogeneity leads to low $r_{Tq}$ at large averaging time regardless of season at both sites and there are seasonal changes of $r_{Tq}$ in mid-averaging times at industrial site, possibly due to seasonal change of trees and grasses near the site.

• 한국농공학회지
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• 제40권4호
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• pp.45-57
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• 1998

This study was conducted to derive optimal design floods by Generalized Extreme Value (GEV) distribution for the annual maximum series at ten watersheds along Han, Nagdong, Geum, Yeongsan and Seomjin river systems. Adequacy for the analysis of flood data used in this study was established by the tests of Independence, Homogeneity, detection of Outliers. L-coefficient of variation, L-skewness and L-kurtosis were calculated by L-moment ratio respectively. Parameters were estimated by the Methods of Moments and L-Moments. Design floods obtained by Methods of Moments and L-Moments using different methods for plotting positions in GEV distribution were compared by the Relative Mean Errors(RME) and Relative Absolute Errors(RAE). The results were analyzed and summarized as follows. 1. Adequacy for the analysis of flood data was acknowledged by the tests of Independence, Homogeneity and detection of Outliers. 2. GEV distribution used in this study was found to be more suitable one than Pearson type 3 distribution by the goodness of fit test using Kolmogorov-Smirnov test and L-Moment ratios diagram in the applied watersheds. 3. Parameters for GEV distribution were estimated using Methods of Moments and L-Moments. 4. Design floods were calculated by Methods of Moments and L-Moments in GEV distribution. 5. It was found that design floods derived by the method of L-Moments using Weibull plotting position formula in GEV distribution are much closer to those of the observed data in comparison with those obtained by method of moments using different formulas for plotting positions from the viewpoint of Relative Mean Errors and Relative Absolute Errors.

• Nuclear Engineering and Technology
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• 제28권1호
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• pp.56-71
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• 1996

지지격자를 갖는 5$\times$5 핵연료 봉다발부수로내에서 국부 수력특성인자들을 레이저 유속측정장치인 LDV(Laser Doppler Velocimeter)를 이용하여 측정하였다. 이 연구는 지지격자가 봉다발 난류유동구조에 미치는 영향에 관한 연구에 관점을 두었다. 축방향속도, 난류강도, 편이도, 편평도 등의 측정인자들을 측정하였다. 압력강하를 측정하여 지지격자의 손실계수와 봉다발의 마찰계수를 구하였다 실험결과로부터 활발한 난류혼합거리는 지지격자로부터 x/D$_{h}$=10까지이고, 강제 혼합거리는 지지격자로부터 x/D$_{h}$=20까지임이 관찰되었다. 지지격자하류에서의 축방향 난류강도 감쇄거동은 mesh격자나 screen을 통과하는 난류유동과 같은 경향을 보여주었다. 측정된 자료로부터 부수로해석 code에 입력함수로 적용할 수 있는 국부 난류혼합계수상관식을 구하였다. 국부 혼합계수분포 경향을 관찰하여보면 지지격자 근처에서 최대값을 보이고, 하류방향으로 진행하면서 안정된 값을 갖는다.

• 한국식품영양과학회지
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• 제19권3호
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• pp.248-262
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• 1990

General purpose of the study was to understend nutritional status of the Korean farmers and thus provide rural nutrition intervention programs with more useful in formation and data. The data for the study was collected two times from the 603 sample farm households in 1982 and 1987. The main results of the study were as follows ; 1) Food intake of the Korean farmers was highly dependent upon vegetable foods especially on cereals and gains. However the unbalanced food intake pattern was gradually improved as consumption of vegetable foods was decreased from 992.8 grams per person per day in 1982 to 946.4g in 1987 and that of animal foods increased from 54.2g to 91.4g . 2) In mean value analysis on nutrient intake of the farmeres intakes of energy and protein were nearly reached to Recommended Dietary Allowances(RDA) level; intakes of calcium vitamin A and riboflavin were quite deficient whereas iron thiamin niacin and ascorbic acid were well over. From 1982 to 1987 intakes of all nutrients except energy were increased. 3) In distribution analysis on nutrient intake coefficient of variation(CV) of all nutrients except iron was increased. skewness(SK) the coefficients of calcium iron vitamin A riboflavin and ascorbic acid were decreased Kurtosis (Ku) of iron and vitamin A was increased. On the whole distributions of nutrient intake of the farmers were changed in undesirable ways although the mean values of the nutrient intake were improved 4) In relationship analysis among 115 relationships 76 relationships were consistent between 1982 and 1987. Of 76 consistent relationships only 10 relationship were significant at 5% level such as the protein intake level and the balance of food intake calcium intake level and the age etc.