• Journal of Electrical Engineering and Technology
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• 제8권4호
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• pp.840-849
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• 2013

This paper presents a statistical approach to analyze electrical tree inception voltage, electrical tree breakdown voltage and tree breakdown time of unsaturated polyester resin subjected to AC voltage. The aim of this work was to show that Weibull and lognormal distribution may not be the most suitable distributions for analysis of electrical treeing data. In this paper, an investigation of statistical distributions of electrical tree inception voltage, electrical tree breakdown voltage and breakdown time data was performed on 108 leaf-like specimen samples. Revelations from the test results showed that Johnson SB distribution is the best fit for electrical tree inception voltage and tree breakdown time data while electrical tree breakdown voltage data is best suited with Wakeby distribution. The fitting step was performed by means of Anderson-Darling (AD) Goodness-of-fit test (GOF). Based on the fitting results of tree inception voltage, tree breakdown time and tree breakdown voltage data, Johnson SB and Wakeby exhibit the lowest error value respectively compared to Weibull and lognormal.

• 대한간호학회지
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• 제39권5호
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• pp.700-708
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• 2009

Purpose: This study was done to test the validity and reliability of the Adolescent Mental Problem Questionnaire (AMPQ) for Korean high school students. Methods: The AMPQ was designed to assess adolescents', mental health status and problem behavior (Ahn, 2006). A methodological study design was used with exploratory factor analysis, Pearson's correlation coefficients, and a fitness of the modified model for validity. Also, Cronbach's alpha coefficients and alternative-form method for reliability were used. AMPQ was tested with a sample of 36,313 high school students. The participants consisted of 18,701 males and 17,612 females. Results: Seven factors were extracted through factor analysis: 'Psychiatric problems', 'Delinquency', 'Academic troubles', 'Family problems', 'Hazardous behavior', 'Harmful circumstance', 'Eating problems'. These factors explained 51.1% of the total variance. The fitness of the modified model was good ($X^2$=38,413.76, Goodness of Fit Index [GFI]=.94, Adjusted Goodness of Fit Index [AGFI]=.93, Comparative Fit Index [CFI]=.95, Root Mean Square Error of Approximation [RMSEA]=.05), and concurrent validity with Korea-Youth Self-Report [K-YSR] was .63. Cronbach's alpha coefficient of the 31 items was .85. Conclusion: The results of present study suggest that the modified AMPQ instrument may be useful for efficiently assessing mental health status and problem behavior in late adolescent, high school students.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.331-335
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• 1999

The present study describes the analysis of the multiphasic growth function (MGF) to body weight in laboratory and wild mice. Three genetic groups of laboratory mice (Mus musculus domesticus) designated $CF_{{\sharp}1}$, C3H/HeNCrj and C57BL/6NCrj, and a genetic group of Yonakuni wild mice (Mus musculus molossinus yonakuni, Yk) were used. Mean body weights of each genetic group-sex subclass from birth to 69 days of age taken at 3-day intervals were analyzed by a monophasic, diphasic and triphasic functions for describing growth patterns. A comparison among the three functions of the MGF was based on the goodness-of-fit criteria: residual standard deviation (RSD), adjusted R-square (Adj $R^2$) and Akaike's information criterion (AIC). Result of this study indicated that body weight averaged heavier for males than for females. Among the four genetic groups within both sexes, $CF_{{\sharp}1}$ showed the highest, subsequent followed by C3H/HeNCrj, C57BL/6NCrj and Yk. Comparison among the three functions revealed that the triphasic function was the best fit to growth data, with the lowest RSD, the highest Adj $R^2$ and the lowest AIC, for the four genetic groups. For the triphasic function, RSD within each genetic group-sex subclass was similar for males and females. Adj $R^2$ was 0.999 for all genetic group-sex subclasses. AIC for laboratory mice males and females ranged from -70.48 to 66.50 and from -92.81 to -68.64, respectively; whereas for Yk wild mice males was -74.29 and females -78.42.

• Asian-Australasian Journal of Animal Sciences
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• 제26권8호
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• pp.1119-1126
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• 2013

The objective of this study was to compare the goodness of fit of four lactation curve models: Wood's Gamma model (WD), Wilmink (WL), and Pollott's multiplicative two (POL2) and three parameters (POL3) and to determine the environmental factors affecting the complete lactation curve of F1 dairy sheep under organic management. A total of 5,382 weekly milk yields records from 150 ewes, under organic management were used. Residual mean square (RMS), determination coefficients ($R^2$), and correlation (r) analysis were used as an indicator of goodness of fit for each model. WL model best fitted the lactation curves as indicated by the lower RMS values (0.019), followed by WD (0.023), POL2 (0.025) and POL3 (0.029). The four models provided total milk yield (TMY) estimations that were highly correlated (0.93 to 0.97) with observed TMY (89.9 kg). The four models under estimated peak yield (PY), whereas POL2 and POL3 gave nearer peak time lactation estimations. Ewes lambing in autumn had higher TMY and showed a typical curve shape. Higher TMY were recorded in second and third lambing. Season of lambing, number of lambing and type of lambing had a great influenced over TMY shaping the complete lactation curve of F1 dairy sheep. In general terms WL model showed the best fit to the F1 dairy sheep lactation curve under organic management.

• 한국치위생학회지
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• 제12권4호
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• pp.675-684
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• 2012

Objectives : The purpose of this study was to develop an instrument for Korean Scaling Fear (KSF)-1.1 in scaling patients. Methods : 402 sample size for scaling patients was studied in Daegu city in July and August of 2011. Mean and standard deviation was calculated in 3 dimensions(FWS: fear while scaling, DDH: distrust on dental hygienist, FAS: fear after scaling). Results : Age of 402 subjects was 36.5 years. In analyzing reliability for item-level, a range of correlation coefficient(${\alpha}$) on item-internal consistency(FWS, DDH, and FAS) was 0.58~0.88(${\alpha}$=0.90), 0.40~0.71(${\alpha}$=0.82), and 0.54~0.63(${\alpha}$=0.82), respectively. Floor(%) and ceiling(%) value on 3 dimensions were also 9.2% and 4.0%, 12.4% and 0.5%, and 17.7% and 1.2%, respectively, therefore, we found statistically high reliability for those(p<0.001). With explanatory factor analysis, this study could generate 3 dimensions(factor 1, eigenvalue 5.41, proportion 0.49; factor 2, eigenvalue 1.50, proportion 0.14; factor 3, eigenvalue 1.04, proportion 0.09) and 11 sub-scales. Also confirmatory factor analysis results showed that the KSF1.1 model was fitted very well in analysis of model fit($x^2$=112.94, df=41, p=0.000; goodness of fit index=0.95; adjusted goodness of fit index=0.92; root mean square residual=0.057). Conclusions : In conclusion, The findings of this study showed that developed reliable and valid instrument for measuring the KSF1.1 in the scaling patients.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.178-180
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• 2016

군 무기체계에 사용되는 정밀측정장비는 수명주기 동안 측정신뢰성을 유지하기 위해 주기적으로 교정을 수행하고 있으며, 기관들은 장비 신뢰성을 향상시키면서 비용을 최소화하기 위한 증가하는 압력에 직면하고 있다. 이전 연구들은 샘플의 크기와 장비 특성을 고려하여 측정신뢰성 모델을 결정하도록 추천하고 있으나, 다양한 장비의 정비 데이터에 대해 단일 모델을 적용하는 것은 적합하지 않을 수 있다. 본 논문에서는 정비 데이터 기반 주요 측정신뢰성 모델들에서 계산된 교정주기를 통계적인 유의수준 검증을 통한 적합성 검정으로 추천하도록 제안하고자 한다. 실제 제안된 방법으로 다양한 종류의 장비에 대해 교정주기 분석방법을 적용한 결과, 교정주기 만료까지 신뢰도가 유지됨을 확인하였다.

• 응용통계연구
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• 제24권6호
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• pp.987-994
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• 2011

모집단이 부도와 정상상태로 구분되는 신용평가 관점에서 부도와 정상 상태의 조건부 누적분포함수를 추정하는 방법으로 정규혼합 분포추정과 kernel density estimation을 이용하는 분포추정을 고려한다. 정규혼합 분포의 모수를 EM 알고리즘을 사용해 추정하고, KDE 방법에서는 많이 사용하는 다섯 종류의 커널 함수와 네가지의 띠폭을 이용한다. 그리고 추정한 분포로부터 구한 각각의 ROC 함수를 구한다. 추정한 분포들의 적합도를 비교 분석하고, 이를 바탕으로 구한 ROC 곡선의 성과를 비교 토론한다. 본 연구에서는 KDE 방법으로 추정한 분포함수가 더 적합하고, 추정한 정규혼합 분포를 이용한 ROC 함수가 더 좋은 성과를 나타내는 것을 발견하였다.

• 한국콘텐츠학회논문지
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• 제12권3호
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• pp.161-170
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• 2012

본 연구는 선행연구에서 도출된 무용영재성 구성요인을 바탕으로 무용영재를 판별할 수 있는 구조화된 평가도구를 개발하는 것이 목적이다. 무용영재의 잠재성을 대변할 수 있는 적합한 문항을 개발하기 위하여 무용영재성 구성요인인 신체적 조건, 동작수행능력, 표현 및 창의성, 무용태도 요인을 바탕으로 초기문항을 개발하였다. 1차 기초조사는 무용을 전공자와 직업무용단 단원 등을 조사 대상자로 선정하여 총 206명에게 실시하였고, 설문조사 결과자료를 바탕으로 기술통계 분석과 신뢰도 분석, 그리고 탐색적 요인분석을 실시하였다. 그 결과, 4요인(신체적요인, 표현 및 창의성, 무용태도, 동작수행능력)과 20개의 문항이 선정되었다. 선정된 모형(4개의 구인과 20개의 문항)의 적합도를 알아보기 위하여 1차 설문조사 대상과는 다른 무용전공생과 직업무용단 단원 등을 선정하여 총 292명에게 2차 기초조사를 실시하였다. 설문조사 결과자료를 바탕으로 확인적 요인분석을 실시한 결과, 모든 적합도 지수가 기준치에 만족하는 것으로 나타났다. 본 결과를 통해 4요인의 20개인 문항에 대한 모형은 적합한 것으로 판명되어 최종으로 채택하였다.

• 한국융합학회논문지
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• 제13권5호
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• pp.129-136
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• 2022

이 연구의 목적은 서퍼의 체험과 러브마크, 몰입, 소비행동의도 간의 구조적 관계를 검증하는데 있다. 설정한 연구모형에서 체험, 러브마크, 몰입, 소비행동의도 간의 관계를 알아보기 위하여 적합도 검증을 진행하였다. 결과는 다음과 같다. 첫째, 연구모형의 적합도 검증 결과 모든 지수가 적합도 기준에 부합하는 것으로 나타나 체험, 러브마크, 몰입, 소비행동의도 간의 관계를 예측하기 적합한 모형으로 나타났다. 둘째, 체험은 러브마크에 통계적으로 유의한 영향력이 있는 것으로 나타났다. 체험은 몰입에 통계적으로 유의한 영향력이 있는 것으로 나타났다. 몰입은 소비행동의도에 정적인 영향을 미치는 것으로 나타났다. 러브마크는 소비행동의도에 통계적으로 유의한 영향력이 있는 것으로 나타났다. 체험은 소비행동의도에 통계적으로 유의한 영향력이 없는 것으로 나타났다.

• 한국군사과학기술학회지
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• 제17권2호
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• pp.204-212
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• 2014

The purpose of this paper is to investigate the effects of calibration rounds on the statistical distribution of the muzzle velocity in acceptance test of propelling charge. It is shown that the normal distribution fits best among statistical distributions from goodness-of fit test. The 3p-Weibull distribution is also acceptable because the shape of the probability density function curve is similar to that of normal distribution and it also has near zero skewness value. Muzzle velocities of test rounds uncompensated by calibration rounds showed high variation and had comparatively higher skewness. Because the skewness of normal distribution is defined to be zero, calibration rounds make the normality of data higher.