• Communications for Statistical Applications and Methods
• /
• 제27권2호
• /
• pp.189-199
• /
• 2020

This paper studies a Bayesian ordered multiple linear regression model with skew normal error. It is reasonable that the kind of inherent information available in an applied regression requires some constraints on the coefficients to be estimated. In addition, the assumption of normality of the errors is sometimes not appropriate in the real data. Therefore, to explain such situations more flexibly, we use the skew-normal distribution given by Sahu et al. (The Canadian Journal of Statistics, 31, 129-150, 2003) for error-terms including normal distribution. For Bayesian methodology, the Markov chain Monte Carlo method is employed to resolve complicated integration problems. Also, under the improper priors, the propriety of the associated posterior density is shown. Our Bayesian proposed model is applied to NZAPB's apple data. For model comparison between the skew normal error model and the normal error model, we use the Bayes factor and deviance information criterion given by Spiegelhalter et al. (Journal of the Royal Statistical Society Series B (Statistical Methodology), 64, 583-639, 2002). We also consider the problem of detecting an influential point concerning skewness using Bayes factors. Finally, concluding remarks are discussed.

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

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

• 기본간호학회지
• /
• 제9권2호
• /
• pp.190-200
• /
• 2002

Purpose; The purpose of this study was to develop an instrument to measure sexual satisfaction in Korean adults. Method: Development of items for the instrument was done by a collecting, reorganizing, reducing and selecting process based on the literature. A total of 19 items were selected in this process. For evaluation of the appropriateness of the 19 items, questionnaires were given to an expert group consisting of 18 professionals (7 men and 11 women). Eighteen items having a response of 70% in 'very good' item or 'good' item were included as items for the instrument. With these 18 items, a 5 point Likert scale was developed, and reliability and validity tests of the scale were done. The subjects for the test were 1,127 Korean adults living in 11 areas in Korea, Data were collected from Dec. 1, 2000 to Feb. 28, 2001 and analyzed with SPSS/PC+ 10.0 program. Item analysis and factor analysis were used to assess the reliability and validity of the scale. Chronbach alpha and corrected item-total correlation were obtained to verify internal consistency, and principal component analysis with the varimax rotation was used to identify structure validity of the developed tool. Result: Reliability of the scale was .9503 and corrected item-total correlations of the items were distributed from .5208 to 7899. As a result of the factor analysis, the items were categorized into three factors. The cumulative variance of the three factors was 67.1%, and all of the variances of the factors were above 5%. Because factor 1 (8 items) indicated a special feeling of psychological satisfaction with sexual activity, it was named 'psychological factor'. Factor 2 (8 items) indicated a feeling of satisfaction in the interaction with sexual partner through communication and variation, therefore it was named 'interactional factor'. Factor 3 (2 items) was about the frequency and duration of sexual intercourse and indicated physical dimensions of satisfaction, so it was named 'physical factor'. The average score for sexual satisfaction of the 1,127 subjects was 65.32 (${\pm}12.71$), and histogram of the score showed a normal distribution with skewness - .425. Conclusion: Finally, a Korean Sexual Satisfaction Scale(KSSS) was accepted as a 5 point Likert scale with 18 items after the statistical test for reliability and validity. In conclusion, KSSS is a useful instrument which is valid and reliable can be used to understand the sexuality of Korean adults.

• 한국노년학
• /
• 제29권1호
• /
• pp.117-134
• /
• 2009

본 연구의 목적은 노인들에게 맞는 건강한 노후에 관한 안정적인 신뢰도와 적절한 타당도를 갖춘 척도를 개발하는 것이다. 서울에 거주하고 노인복지관을 다니며, 정기적으로 운동을 하고 있는 노인 전체 335명(예비 척도 개발에 65세 이상의 노인 127명, 1차 본 조사 척도 개발에 62명, 2차 본 조사 척도 개발에 146명을 대상)을 대상으로 하였고, 건강한 노후에 관한 개방형 질문지와 개발된 건강한 노후 척도를 통해 설문지의 타당도와 신뢰도를 검증하였다. 조사기간은 2006년 6월 12일부터 2006년 10월 27일까지 실시되었고, 자료처리는 Window용 SPSS 통계 Package 12.0 Version을 이용하여 평균, 표준편차, 첨도, 왜도, 신뢰도 분석, 탐색적 요인 분석, 확인적 요인분석을 실시하였다. 연구의 결과는 다음과 같이 나타났다. 첫째, 구성 개념 틀에 근거하여 만들어진 25개의 문항들에 대해서는 노인관련 전공교수 1명, 노인 여가학 박사 2명 등의 자문집단을 통해 내용타당도를 높였다. 둘째, 탐색적 요인분석 결과 건강한 노후 척도는 신체적 건강(6문항), 인지·정신적 건강(6문항), 사회·지지적 건강(8문항)의 3개의 하위요인으로 추출되었다. 셋째, 신뢰도 검사 결과 전체 문항에 대한 Cronbach's α는 .891로 높은 신뢰도를 보였고, 요인별 설문지의 내적 일관성 검정 결과는 각각 .642에서 .885의 범위를 나타냈다. 넷째, 확인적 요인분석 결과 본 연구에서 적합지수로 판단한 NFI, RFI, CFI, Delta 2 IFI값들 은 1에 가깝게 나타났다. 따라서 본 연구에서 결과로 도출된 타당도와 신뢰도의 결과들을 살펴봤을 때, 개발된 건강한 노후에 대한 설문지는 예비조사, 본 조사의 과정을 거쳐 확인된 신뢰도와 타당도가 이론적 기준에 벗어나지 않은 적절한 도구이며, 특히 노인들의 건강한 노후 생활에 대한 기준과 틀을 제시한다는 점에서 그 의의가 있다고 하겠다.

• 실천공학교육논문지
• /
• 제15권1호
• /
• pp.1-11
• /
• 2023

본 연구는 가상훈련 학습자의 가상훈련 콘텐츠 활용 만족도를 측정하는 도구 개발 및 타당화하는 것이 목적이다. 이를 위해 K대학교 온라인평생교육원에서 2011년부터 2022년까지 가상훈련 만족도로 활용한 문항을 토대로 기초문항을 도출하였다. 이후, K대학교 온라인평생교육원 포털 STEP에 접근한 학습자를 대상으로 온라인 설문조사를 실시하여 성실하게 응답한 총 491부를 최종분석에 사용하였다. 최종 사용한 491부의 자료는 기초문항분석, 탐색적 요인분석, 신뢰도 분석, 확인적 요인분석 등의 방법으로 분석하였다. 첫째, 기초문항분석에서 평균 4점이상, 왜도 ±2, 첨도 ±4이상의 수용기준을 벗어난 문항은 없었다. 둘째, 탐색적 요인분석 실시 후 도출된 가상훈련 콘텐츠 만족도 하위요인별 상관계수는 r=.682 ~ .822(p<.01)로 나타나 양호하였다. 하위요인별 신뢰도 계수는 콘텐츠 내용 .849, 콘텐츠 활용 .922, 시스템 및 운영지원 .841, 활용지속의향 .920, 전체신뢰도는 .956로 매우 높게 나타났다. 셋째, 확인적 요인분석 결과, 구성개념도는 .842 ~ .926로 나타나 추천기준치인 .7보다 높았으며, 평균분산추출도 .640 ~ .796으로 나타나 추천기준치인 .5보다 높아 각각 구성개념에 대한 대표성을 갖고 있다고 볼 수 있다. 가상훈련 학습자의 콘텐츠 만족도 구인 타당성을 검증한 결과로 콘텐츠 내용, 콘텐츠 활용, 시스템 및 운영지원, 활용지속의향 등 4개 요인 모형이 도출되었다. 본 연구는 가상훈련 학습자의 콘텐츠 만족도 측정도구를 실증적으로 개발하여 준거 틀과 기준을 제공했다는데 의의가 있다.

• 한국전산유체공학회지
• /
• 제17권2호
• /
• pp.42-52
• /
• 2012

Direct Numerical Simulation(DNS) of turbulent mass transfer in fully developed turbulent pipe flow has been performed to study the effect of wall boundary conditions on the concentration fields at $Re_{\tau}$=180 based on friction velocity and pipe radius. Fully developed turbulent pipe flows for Sc=0.71 are studied with two different wall boundary conditions, namely, constant mass flux and constant wall concentration. The mean concentration profiles and turbulent mass fluxes obtained from the present DNS are in good agreement with the previous numerical results currently available. To investigate the effects of wall boundary condition on the turbulent mass transfer, the mean concentration profile, root-mean-square of concentration fluctuation, turbulent mass fluxes and higher-order statistics(Skewness and Flatness factor) are compared for the two cases. Furthermore, the budgets of turbulent mass fluxes and concentration variance were computed and analyzed to elucidate the effects of wall boundary conditions on the turbulent mass transfer.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제49권1호
• /
• pp.19-23
• /
• 2000

Partial discharges(PD)in air insulated electric power apparatus often lead to deterioration of solid insulation by electron bombardments and electrochemical reaction. The PD caused to reduce the life time of power apparatus and to increase power losses. Thus understanding and classification of PD patterns in air are very important to discern sources of PD. In this paper, PD in air by using statistical methods was investigated. We classified air discharges, corona, surface discharges and cavity discharges by Kohonen network. For classification of PD patterns, we used statistical operators and parameters such as skewness$(S^+,\; S^-),\; kurtosis(K^+, K^-),\; mean phase(AP^+, AP^-)$, cross-correlation factor(CC) and asymmetry derived from the mean pulse-height phase distribution$(H_{avg}(\phi))$, the max pulse-height phase distribution $(H_{qmax}(\phi))$, the pulse count phase distribution $(H_n(\phi))$ and the pulse height vs. Repetition rate $(H_q(n))$.

• 가정과삶의질연구
• /
• 제7권2호
• /
• pp.85-94
• /
• 1989

The purpose of the study was to examine the characteristics of the Kansas Marital Satisfaction Scale(KMSS). KMSS was designed as a short and direct assessment of marital satisfaction. The scale consists of three items where respondents are directly asked how satisfied they are with their marriage, with their partner as a spouse, and with their relationship with their spouse. 1) Through item analysis, three items were significant discrimination for husbands and wives. 2) The KMSS consisted of 1 factor for husbands and wives. 3) Cronbach alpha estimates of internal consistency reliability of 93 for husband and of 89 for wives. 4) For wives, the item means between satifaction with their marriage and satisfaction with their relationsphip with their husbands were significantly different, even though the items were highly correlated. For husbands, three item means weren't significantly different. 5) The distribution of responses to the scale for husbands and wives departed si nificantly from normality in terms of skewness and kurtosis. 6) The scale was correlated, in expected directions, with the Marital Comparison Level Index (MCLI) and Marital Instability Index(MII), for husbands and wives. In conclusion, the scale offers promise for use in clinical evaluation and survey research where a brief but reliable measure of marital satisfaction is required.

• 수산해양교육연구
• /
• 제24권5호
• /
• pp.616-626
• /
• 2012

The purpose of this study is to verify career maturity, achievement goal, learning attitude and academic achievement relation with subjects-related career education of middle school students. To achieve these aims, this study used SELS(Seoul education longitudinal study) of Seoul Education Research & Information Institute. Also, analysis as well as descriptive statistics calculation on average, deviation, skewness and kurtosis of variable factor and calculated characteristic item and degree of reliability(Cronbach ${\alpha}$). For goodness of fit test, this study used TLI(Tucker-Lewis index) and RMSEA(Root mean square error of approximation). To achieve the ultimate objects, this study used LMA(latent mean analysis) for analysis of difference career maturity, achievement goal, learning attitude and academic achievement relation with subjects-related career education in middle school students. The results are as follows. First, experience relation with subjects-related career education were influenced on career maturity with career cognition. Second, experience relation with subjects-related career education were influenced on achievement goal, learning attitude, and larger than career maturity and academic achievement. Third, experience relation with subjects-related career education were influenced on middle school students more than inexperienced relation with subjects-related career education.