• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.163-170
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• 2023

The user-based collaborative filtering technique, one of the implementation methods of the recommendation system, recommends the preferred items of neighboring users based on the calculations of neighboring users with similar rating histories. However, it fundamentally has a data scarcity problem in which the quality of recommendations is significantly reduced when there is little common rating history. To solve this problem, many existing studies have proposed various methods of combining Jaccard index with a similarity measure. In this study, we introduce a time-aware concept to Jaccard index and propose a method of weighting common items with different weights depending on the rating time. As a result of conducting experiments using various performance metrics and time intervals, it is confirmed that the proposed method showed the best performance compared to the original Jaccard index at most metrics, and that the optimal time interval differs depending on the type of performance metric.

• Journal of the Institute of Convergence Signal Processing
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• v.5 no.3
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• pp.173-180
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• 2004

In this paper we provide a new image restoration method based on the multiscale regularization in the redundant wavelet transform domain. The proposed method uses the redundant wavelet transform to decompose the single-scale image restoration problem to multiscale ones and applies scale dependent regularization to the decomposed restoration problems. The proposed method recovers sharp edges by applying rather less regularization to wavelet related restorations, while suppressing the resulting noise magnification by the wavelet shrinkage algorithm. The improved performance of the proposed method over more traditional Wiener filtering is shown through numerical experiments.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.3
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• pp.343-347
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• 2010

This paper presents an efficient image recognition method using the hybrid coefficient measure of correlation and distance. The correlation coefficient is applied to measure the statistical similarity by using Pearson coefficient, and distance coefficient is also applied to measure the spacial similarity by using city-block. The total similarity among images is calculated by extending the similarity between the feature vectors, then the feature vectors can be extracted by PCA and ICA, respectively. The proposed method has been applied to the problem for recognizing the 960(30 persons * 4 expressions * 2 lights * 4 poses) facial images of 40*50 pixels. The experimental results show that the proposed method of ICA has a superior recognition performances than the method using PCA, and is affected less by the environmental influences so as lighting.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.9 no.2
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• pp.198-208
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• 1998

The purpose of this study was to develop a 'Korean Child Rearing Attitudes Inventory', in order to understand the effects of parents rearing attitudes on social phobia. The total subjects were 392 high school students in Seoul. The scales wwereadministered to the subjects and we examined the reliability and validity. The results were as follows. According to the factor analysis, six factors abstracted from the father's rearing attitudes：rejection, high expectation, anxious, control, emotional care and overconcern of other's opinion. By the method of reliability analysis and factor analysis, finally selected items were 60. The reliability of the factors ranged from .76 to .90 by Cronbach ${\alpha}$. Five factors abstracted from the mother's rearing attitudes：anxious, high expectation, rejection, emotional care and overconcern of other's opinion. And total selected items of mother's rearing attitudes were 61. The reliability of the factors ranged from .72 to .91 by Cronbach ${\alpha}$. The construct validity and reliability of this inventory were supported.

• Korean Journal of Social Welfare
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• v.61 no.3
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• pp.55-76
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• 2009

This study tested the psychometric properties of the Korean version of the Capacity-to-Consent Screen: K-CCS) scale. A total of 404 South Korean older adults were e Cruited using the purposive sampling method. The participants were asked to res-Cod to a structured questiConaire which included older adults' characteristics, ADLs, IADLs, cognitive impairments and creen: K-CCS) scale. A total of. Item analysis, explonalory factor analysis(EFA), and ) sfirmalory factor analysis(CFA) were cCoducted to verifK-Che psychometric properties of the Korean Version of CCS. The sample was divided into two groups: one group for EFA(n=202) alysis(Eois(r group for CFA(n=202). The totults revealeysisae. he final version of the 8-item K-CCS with two dimensions had a excellent internof. Itemstencyonofpha value=.f) alysa CFA) sfirmed the acceptaas diviof the modef.fdi(RMSEA=.057, NNFI=.f4, IFI=.f6, CFI=.f6) to twaddition, claims for the convergent and criterion-related validdiviwere demItetnaled. Ity-tnclusion, the K-CCS can be rmed for professi sams to asersioolder participants' capacity to consent to clinical or survey research.

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.393-406
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• 2018

The depression and anxiety are the most popular mental disorders and not easy to distinguish because of their lots of similarities in the diagnostic criteria, related theories, and clinical symptoms. In this article, we developed the affect scale for distinguishable diagnosis, utilized the relationships between the Positive and Negative affect, and the depression and anxiety. We made up the seed scale of the items which selected by partial correlation, and set the scoring up by multiple regression method. The Multi-dimentional affect scale is reliable and working similarly as the scales used before, but less correlated to each other. We conclude that the affect scale achieved the diagnosis for distinguish between depression and anxiety. Our suggestions for the further study are to redeem the cultural differences, modify by the elaborate methods, and validate by the actual clinical data.

• Korean Journal of Psychosomatic Medicine
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• v.19 no.2
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• pp.92-100
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• 2011

Objectives：We developed a Korean version of the Brief Measure of Worry Severity(BMWS), and examined its reliability, validity, and factor structures. We also explored the associations of pathological worry with depression and anxiety. Methods：Three hundreds fifty-two subjects including community population and college students completed the BMWS, and 27 subjects repeated the scale three weeks later. Reliability was assessed by Cronbach's coefficient ${\alpha}$ and test-retest correlation. The external validity was examined by the correlation of the BMWS score with the scores of Beck Depression Inventory(BDI), Patient Health questionnaire-2(PHQ-2), State Anxiety Inven-tory(SAI), and Trait Anxiety Inventory(TAI). And principal component analysis was performed to evaluate the construct validity. The associations of pathological worry with depression and anxiety were explored using partial correlation analysis. Results：Cronbach's coefficient ${\alpha}$ for the BMWS was 0.904 and test-retest correlation was 0.56(P<0.01). The Spearman correlation coefficients of the BMWS score with the scores of BDI, PHQ-2, SAI, and TAI were 0.60(P<0.01), 0.42(P<0.01), 0.36(P<0.01), and 0.59(P<0.01), respectively. The BMWS showed unifactorial construct. When controlling for TAI score, the correlation coefficient between the BMWS score and the BDI score was 0.357(P<0.01), and when controlling for BDI score the correlation coefficient between the BMWS score and the TAI score was 0.446(P<0.01). Conclusion：The Korean version of the BMWS was found to be a reliable and valid questionnaire for measuring pathological worry. And we could identify the associations of the pathological worry with depression as well as anxiety.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.1405-1408
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• 2011

소프트웨어 품질 측정은 소프트웨어 공학의 필수적인 요소이다. 소프트웨어 품질 척도 중 하나인 결합도는 모듈간의 얼마나 강하게 연결되어있는지를 나타낸다. 결합도는 소프트웨어의 결함-경향성, 모듈화, 재사용성, 변경-경향성 등 다양한 목적으로 사용된다. 기존의 결합도 척도들은 메소드호출 횟수에 의해서 결정되는데, 이는 메소드의 가중치를 고려하지 않기 때문에 결합도를 정확히 측정 하지 못한다. 본 논문은 페이지랭크 알고리즘을 이용하여 메소드의 가중치를 측정하고, 이를 이용한 결합도 척도 개선 방법에 대해 제안한다. 본 논문의 유효성을 검증하기 위하여, 4 개의 오픈 소스 프로젝트를 대상으로 기존의 방법과 개선된 방법으로 결합도 척도 3 개를 측정하였다. 개선된 결합도 3 개는 유지보수의 척도로 사용되는 변경-경향성(Change-Proneness)과의 상관계수가 기존의 결합도 척도에 비하여 눈의 띄게 향상되었다. 따라서 개선된 결합도 척도는 소프트웨어 품질을 더 정확하게 측정할 수 있다.

• Proceedings of the Korean Association for Survey Research Conference
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• 2007.06a
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• pp.139-149
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• 2007

사회조사를 위한 표본설계를 할 때 표본의 크기를 얼마로 할 것인지를 결정하는 문제는 조사연구자에게 고민거리가 된다. 사회조사 중에서 4점 또는 5점 척도로 된 여러 개의 개별 문항들로 구성된 설문지를 사용하는 경우가 많다. 이런 경우 개개의 문항 자체를 직접적으로 하나의 변수로 사용하지 않고 여러 개 문항들을 결합하여 새로운 척도를 만들어 사용하는 것이 일반적이다. 본 연구의 목적은 리커트 척도가 관심변수인 조사연구에서 표본크기를 결정하는 방법을 제공하는 것이다. 리커트 척도를 만들고자 할 때 4점 혹은 5점 척도로 구성된 여러 문항변수들은 일반적으로 서로 양의 상관관계를 가지게 된다. 본 연구에서는 개별 문항변수들은 각각 동일한 분포를 가지며, 각각의 변수들은 서로 동일한 크기의 상관관계를 갖는다는 가정을 한다. 주어진 가정 하에서 새로운 척도의 표본분포를 유도한 후 이를 이용하여 다양한 상황에서의 표본의 크기를 계산한 결과를 표로 제시하게 되는데 표본이론을 잘 모르는 조사연구자들은 이 표를 이용하여 원하는 표본크기를 결정 할 수 있을 것이다.

• Proceedings of the Korean Statistical Society Conference
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• 2000.11a
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• pp.141-146
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• 2000

Shapiro와 Wilk(1972)는 위치모수와 척도모수가 미지인 경우 지수분포의 검정통계량을 제안하였다. 그것은 척도모수의 일반화 최소제곱추정량과 표본분산의 비로 구성되었다. 그러나 이 검정통계량은 일치성을 갖지 않는다. 본 논문에서는 척도모수의 두개의 점근유효추정량으로 구성된 통계량을 고려하고 이의 극한분포를 구하였다. 또한 두 개의 통계량의 검정력을 비교한 결과 제안된 통계량이 변동계수가 1보다 크거나 같은 분포에서 더 좋은 검정력을 가짐을 볼 수 있었다.