• Journal of the Korean Data and Information Science Society
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• 제13권1호
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• pp.165-175
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• 2002

We consider the problem of estimating the change-point in mean change model with the one change-point. Lombard (1987) suggested change-point estimation based on score functions. Gombay and Huskova (1998) derived a class of change-point estimators with the score function of rank. Various change-point estimators with the log score functions of ranks are suggested and compared via simulation.

• 산업공학
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• 제24권4호
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• pp.314-322
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• 2011

This study analyzes a relationship between Data Envelopment Analysis(DEA) efficiency scores and a normalization index in order to examine the validity of DEA models. A normalization index concerned in this study is 'sales per R&D project fund' which is regarded as a crucial R&D project performance evaluation index in practice. For this correlation analysis, three distinct DEA models are selected such as DEA basic model, DEA/AR-I revised model(i.e. DEA basic model with Acceptance Region Type I constraints) and Super-Efficiency(SE) model. Especially, SE model is adopted where efficient R&D projects(i.e. Decision Making Units, DMU's) with DEA efficiency score of unity from DEA basic model can be further differentiated in ranks. Considering the non-normality and outliers, two rank correlation coefficients such as Spearman's ${\rho}_s$ and Kendall's ${\tau}_B$ are investigated in addition to Pearson's ${\gamma}$. With an up-to-date empirical massive dataset of n = 482 R&D projects associated with R&D Loan Program of Korea Information Communication Promotion Fund in the year of 2011, statistically significant (+) correlations are verified between the normalization index and every model's DEA efficiency scores with all three correlation coefficients. Especially, the congruence verified in this empirical analysis can be a useful reference for enhancing the practitioner's acceptability onto DEA efficiency scores as a real-world R&D project performance evaluation index.

• 한국정보과학회논문지:소프트웨어및응용
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• 제36권7호
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• pp.580-589
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• 2009

오늘날, 대부분의 웹 페이지는 블로그영역에서 생성되고 기존의 웹 페이지 또한 블로그영역으로 전환되어가고 있다. 블로그 페이지는 트랙백연결, 블로거, 태그, 댓글과 같은 기폰 웹 페이지에는 존재 하지 않는 특징이 있다. 따라서 이러한 차이를 반영하지 않는 전통적인 웹 페이지 랭킹 알고리즘을 블로그 페이지에 단순히 적용하는 것은 효율적인 검색을 위해 적절하지 않다. 본 논문에서는 이러한 문제를 해결하기 위해 블로그 검색을 위한 "블로그-랭크" 알고리즘을 제안한다. 제안하는 알고리즘은 블로그의 구조적특징들을 활용하여 트랙백 연결성, 블로거의 명성, 사용자 반응성을 평가하고 이를 기반으로 블로그 페이지를 랭크 한다. 우리는 알고리즘의 검색효율성을 증명하기 위해 제안한 알고리즘을 적용한 블로그 검색 시스템을 구현하고 기존의 블로그 검색시스템과 검색효율성을 비교하였으며, 그 결과 블로그 랭크 알고리즘을 적용한 검색시스템이 기존의 검색시스템보다 더욱 뛰어난 검색효율성을 보임을 확인하였다.

• 재활치료과학
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• 제11권2호
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• pp.53-62
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• 2022

목적 : 본 연구는 뇌졸중 환자를 대상으로 한 인지기능 평가 도구 간의 상관성을 알아봄으로써 임상에서 평가 도구를 선정하거나 사용하는데 도움이 될 수 있는 기초자료를 제공하고자 하였다. 연구방법 : 본 연구는 병원 등 의료기관에 입원하여 작업치료를 받는 뇌졸중 환자 51명을 대상으로 실시하였다. 평가 도구는 인지선별검사(Cognitive Impairment Screening Test: CIST), 한국판 간이정신상태검사 2판(Korean-Mini Mental State Examination, 2nd Edition: K-MMSE~2)과 임상치매척도(Clinical Dementia Rating: CDR)를 사용하였다. 평가 도구 점수 간 상관관계는 Spearman's rank correlation coefficient를, 전체 CDR 점수에 따른 CIST와 K-MMSE~2의 총점 비교는 Wilcoxon signed rank test를 이용하여 분석하였다. 결과 : CIST와 K-MMSE~2의 총점 및 전체 CDR 점수 간 상관관계는 CIST와 K-MMSE~2(ρ=.956), CIST와 CDR(ρ=-.957), K-MMSE~2와 CDR(ρ=-.971)에서 통계학적으로 유의미한 상관관계를 보였다(p<.01). CIST와 K-MMSE~2의 하위영역별 점수 간 상관관계는 모든 하위영역에서 통계학적으로 유의미한 상관관계를 보였다(p<.01). 전체 CDR 점수에 따른 CIST와 K-MMSE~2의 총점 비교는 모든 전체 CDR 점수에서 통계학적으로 유의미한 차이를 보이지 않았다(p>.05). 결론 : 본 연구를 통해 뇌졸중 환자를 대상으로 한 CIST, K-MMSE~2 및 CDR 간에 상관성이 있다는 점을 알 수 있었다. 향후에는 다른 대상자를 통한 연구가 진행되기를 바라며, 본 연구의 결과가 병원 등의 임상에서 인지기능 평가 도구를 선정 또는 사용함에 있어 참고자료로 활용되기를 기대한다.

• Communications for Statistical Applications and Methods
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• 제9권1호
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• pp.75-86
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• 2002

We consider the problem of estimating the change-point in mean change model with one change-point. Gombay and Huskova(1998) derived a class of change-point estimators with the score function of rank. A change-point estimator with the log score function of rank is suggested and is shown to be involved in the class of Gombay and Huskova(1988). The simulation results show that the proposed estimator has smaller rose, larger proportion of matching the true change-point than the other estimators considered in the experiment when the change-point occurs in the middle of the sample.

• Safety and Health at Work
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• 제9권4호
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• pp.381-387
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• 2018

Background: Physician behaviors that undermine a culture of safety have gained increasing attention as health-care organizations strive to create a culture of safety and reduce medical errors. We developed, implemented, and assessed a course to teach physicians skills regarding effective coping and interpersonal communication skills and present our results regarding outcomes. Methods: We examined a professional development program specifically designed to address unprofessional or distressed behaviors of physicians, and we evaluated the impact on burnout, quality of life, and emotional flooding scores of the physicians. Assessments of burnout, quality of life, and emotional flooding were assessed preintervention and postintervention. Results: Results demonstrated statistically significant reductions over time in physicians' emotional flooding and emotional exhaustion (EE). Specifically, using a Wilcoxon Signed-Rank test, results revealed that flooding scores at follow-up were statistically significantly lower than at baseline, V = 590, p < 0.05, and EE and personal accomplishment distributions were found to significantly deviate from normal as indicated by Shapiroe-Wilks tests (p < 0.05). A Wilcoxon signed-rank test indicated that EE scores were significantly higher at baseline compared to follow-up 1, V = 285, p < 0.05. Conclusion: We conclude that the physician participants who enrolled in the educational skills training program improved scores on emotional flooding and EE and that this may be indicative of improved skills related to their experiences and learning in the program. These improved skills in physicians may have a positive impact on the overall culture of safety in the health system setting.

• Child Health Nursing Research
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• 제18권1호
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• pp.1-8
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• 2012

Purpose: The purpose of this study was to identify the effects of an empowerment program on nicotine dependency, temptation, self-esteem, and depression for adolescents who smoke. Methods: The study design was a quasi-experimental study with a nonequivalent control group, pre-post design. The participants were 49 adolescents who smoked. Twenty-six adolescents were assigned to the experimental group and 23 to the control group. The intervention was conducted twice a week for 6 weeks. Chi-square test, t-test, paired-test, Wilcoxon rank sum test and Wilcoxon signed rank test were used to analyze the data. Results: After program, scores for self-esteem (t=5.560, p=.014), were significantly higher and scores for depression (t=-2.111, p=.040) were significantly lower for adolescents in the experimental group compared to adolescents in the control group. Conclusion: The finding indicate that the empowerment group training program was effective in improving self-esteem, and decreasing depression and could be considered as a positive program for smoking cessation for adolescents who smoke.

• 수산경영론집
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• 제46권2호
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• pp.111-125
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• 2015

This study is to analyze the efficiency of Korean sea food manufacturing using Data Envelopment Analysis. Firstly, based on an output oriented traditional CCR, BCC model, the study estimated the efficiency scores. The average estimates of technical, pure technical, and scale efficiency turned out 0.6517, 0.7184, 0.9074 respectively, which are separated for 50 marine corporations. The 10 DMUs were efficient under CCR model while the 17 DMUs under BCC model. Also, the study suggested that the operating profit of the two output factors should be more increased relatively and averagely from the viewpoint of efficiency improvement. Secondly, super efficiency scores are estimated under super efficiency and SBM model. As a result, it came to be possible to distinguish and rank the efficiency of the efficient DMUs. The highest score was 4.2975 under Super-CCR, was 2.4947 under Super-BCC, was 2.7160 under SBM-Super-CCR, and was 1.5319 under SBM-Super-BCC model. The average estimates of super efficiency were 0.76 and 0.82 under Super-CCR and Super-BCC model respectively, and were 0.61 and 0.67 under SBM-Super-CCR and SBM-Super-BCC model. Finally, the study conducted a rank-sum test, Wilcoxon-Mann-Whitney test, to find a statistical significance of heterogeneity existing in efficiencies among the sample corporations. The result showed that there was a significant difference in average efficiency between Dried, Salted product manufacturing and Frozen product manufacturing under BCC-Super efficiency model at 10% level of significance. Furthermore, TOBIT model was applied to find out the potential factors that might influence the efficiency, Wilcoxonand the results showed debt and sales cost influenced all of the technical, pure technical, and scale efficiency, while net profit influenced only the technical efficiency.

• Journal of the Korean Data and Information Science Society
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• 제23권3호
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• pp.495-504
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• 2012

이 연구에서는 면접 점수가 발생되는 통계적 모형을 사영에 근거하여 제시하였다. 이 모형은 피면접자의 개인별 참값과 이와 관련된 변수값이 2차원 평면의 X와 Y축의 값으로 주어졌을 때, 심사위원의 시각을 X축과의 각도로 생각하여 이 축에 사영된 값으로서 심사위원의 면접 점수의 평균으로 잡는 방법이다. 이 값에 개인적 편향과 관측 오차를 더해져 심사위원의 관측 면접 점수가 얻어지게 된다. 이 통계적 모형을 사용하여 흔히 사용되고 있는 면접 점수 표준화 방법인 절사평균법, 순위평균법, z-점수평균법을 비교하였다. 이 모의실험에서는 두 가지 면접 형태, 두 가지 면접자 수, 두 가지 면접자의 전문성 정도, 실제 점수와 관련된 변수 간의 분포 두 가지와 세 가지 상관계수가 고려되었다.

• 한국식품위생안전성학회지
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• 제24권3호
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• pp.200-203
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• 2009

우리나라 식품공전상에 수록된 식품군 및 식품유형에 대한 위해순위(risk ranking) 결정은 식품안전관련 위생관리 우선순위 적용 등에 있어 중요한 수단으로 작용할 수 있다. 하지만 세계적인 관심의 증대에도 불구하고 아직까지 국내에서는 체계적으로 수행된 적이 없었다. 본 연구는 식품공전에 포함되어 있는 101개의 식품유형에 대하여 상대적인 위해 순위를 결정하였다. 상대위해도는 노출평가, 심각성평가 및 섭취량 추정부분으로 구성된 위해평가모델을 이용하였다. 추정결과, 즉석섭취식품(RTE)이 가장 높은 위해수준을 나타내었고, 다음이 어육가공품, 빵류 등의 순으로 나타났다. 이러한 식품공전상의 식품유형에 대한 과학적인 위해순위 결과는 식품안전에 있어 가장 많은 영향을 미치는 식품과 이들 식품에 대한 관리목표를 설정하는데 크게 활용될 수 있을 것이다.