• Journal of the Korean Data and Information Science Society
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• 제15권2호
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• pp.423-430
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• 2004

We provide the exact form of a Rao-Robson version of the chi-squared test of multivariate normality suggested by Park(2001). This test is easy to apply in practice since it is easily computed and has a limiting chi-squared distribution under multivariate normality. A self-contained formal argument is provided that it has the limiting chi-squared distribution. A simulation study is provided to study the accuracy, in finite samples, of the limiting distribution. Finally, a simulation study in a nonnormal distribution is conducted in order to compare the power of our test with those of other popular normality tests.

• Journal of applied mathematics & informatics
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• 제1권1호
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• pp.43-48
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• 1994

There are some difficulties in applying the Pearson's Chi-Square Test for the continuous distribution. The problems include how to form class intervals for the test of fit how to employ in the test when the estimators of parameters are obtained from the ungrouped sample so on. In order to solve these problems we use the generalized minimum Chi-Square technique which is a test free of the complications associated with the Peason's Chi-Square test. This paper show how to apply the goodness of fit tests based on generalized minimum Chi-Square technique to the extreme values.

• 전자공학회논문지CI
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• 제42권4호
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• pp.51-58
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• 2005

본 논문에서는 비디오 시퀀스의 자동분류를 지원하기 위한 기반기술로서, 변형된 $\chi^2$-테스트와 자동 임계치-결정 알고리즘을 이용한 장면전환 검출 기법을 제안하였다. 변형된 $\chi^2$-테스트는 기존의 컬러 히스토그램에서 컬러의 각 채널공간(RGB)에 NTSC표준에 따른 명암도 등급을 따로 계산하여 채널의 차이 값을 보다 세분화 할 수 있으며, 인접한 두 프레임사이의 상대적인 컬러 값의 차이를 강조하는$\chi^2$- 테스트를 결합하여 보다 강건한 장면전환 곁출을 시도하고 있다. 자동 임계치-결정 알고리즘은 변형된 $\chi^2$-테스트를 통하여 획득된 인접한 프레임들 사이의 차이 값들을 이용한다. 먼저, 차이 값들에 대한 전체 평균값을 계산한 후, 이 평균값을 만족하는 차이 값들만을 이용하여 다시 평균값을 계산하며, 이러한 평균값의 연속적인 계산 및 누적을 통하여 분산된 차이 값들로부터 가장 최적의 중간 평균값을 취하여 임계치로 설정하는 방법이다. 실험결과 제안된 장면전환 검출 방법과 자동 임계치-결정 알고리즘은 기존의 접근방법보다 효과적이며, 그 우수성을 보여주었다.

• 근관절건강학회지
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• 제18권2호
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• pp.147-157
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• 2011

Purpose: The purpose of this study was to determine the effect of Tai Chi exercise program (Sun style 12 forms) on anxiety, powerlessness, self-esteem in community-dwelling elderly women. Methods: With a quasi-experimental design, a nonequivalent control group pretest-post test was used. Elderly women who agreed to participate in the study were assigned into an experimental group (n=23), or a control group (n=23). The experimental group participated in Tai Chi exercise program for 50 minutes per session, 2 times a week for 11 weeks. Tai Chi exercise program consisted of 10 minutes for warm-up, 35 minutes for main session, and 5 minutes for cooling down exercises. Anxiety, powerlessness, and self-esteem were measured with questionnaires to evaluate the effect of Tai Chi exercise program. The data were analyzed by using Chi-square test, Fisher's exact test, and Mann-Whitney test by a SPSS WIN 12.0 program. Results: The experimental group showed significant improvement for self-esteem (z=-3.130, p=.002), powerlessness(z=-3.267, p=.001), and anxiety (z=-2.932, p=.003) when compared to control group, Conclusions: Tai chi exercise program may be an effective nursing intervention to improve self-esteem and to reduce powerlessness and anxiety in community-dwelling elderly women.

• Journal of the Korean Data and Information Science Society
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• 제16권2호
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• pp.227-236
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• 2005

A chi-squared test of spherical symmetry is suggested. This test is easy to apply in practice since it is easy to compute and has a limiting chi-squared distribution under spherical symmetry. The result of Park(1998) can be used to show that it has the limiting chi-squared distribution. A simulation study is conducted to study the accuracy, in finite samples, of the limiting distribution. Finally, a simulation study that compares the power of our test with those of other tests of spherical symmetry is performed.

• Journal of the Korean Statistical Society
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• 제27권2호
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• pp.197-203
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• 1998

To test the hypothesis of complete or total independence for a multi-way contingency table, the Pearson chi-squared test statistic is usually employed under Poisson or multinomial models. It is well known that, under the hypothesis, this statistic follows an asymptotic chi-squared distribution. We consider the case where all marginal sums of the contingency table are fixed. Using conditional limit theorems, we show that the chi-squared test statistic has the same limiting distribution for this case.

• Communications for Statistical Applications and Methods
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• 제2권2호
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• pp.330-335
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• 1995

The rebustness of one sample Chi-square test for multivariate normal mean vector is investigated when the multivariate normal population is mixed with another multivariate normal population with differing in the mean vector. Explicit expressions for the level of significance and power of the test are derived. Some numerical results indicate that the Chi-square test procedure is quite robust against slight mixtures of multivariate normal populations differing in location parameters.

• 재활간호학회지
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• 제7권2호
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• pp.159-168
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• 2004

Purpose: The purpose of this study was to examine effect of Tai-Chi exercise program on joint flexibility for osteoarthritis patients. To evaluate the effects, quasi-experimental study was used for pre and post test with a nonequivalent control group. Method: Fifty-tow subjects participated in the experiment(twenty-seven for experimental group and twenty-five for control group) and they were from two different senior citizen centers in J city. The experiment period was from April 2002 through August 2002. The experiment group took part in Tai-Chi exercise program for eighteen weeks(three times a week for four weeks and five times a week for fourteen week). The exercise was performed for 50 minutes at every time (15 minutes for warm-up, 30 minutes for Tai-Chi exercise, and 5 minutes for ending). In order to pursue study purpose, the SPSS/WIN 8.0 program was chosen for the statistical analysis; ANCOVA was employed in examining test hypothesis; t-test and $x^2$-test were used to examine homogeneity between experimental and control group. Result: The study results were as follows :Score of vertebral joint flexibility increased significantly after of Tai-Chi exercise program. Score of wrist joint extension increased significantly after of Tai-Chi exercise program. Score of wrist joint flexion increased significantly after of Tai-Chi exercise program. Score of elbow joint extension increased significantly after of Tai-Chi exercise program. Score of elbow joint flexion increased significantly after of Tai-Chi exercise program. There was a slight increase of knee joint extension in the Tai-Chi exercise group compared to control group, but without statistical significance. Score of knee joint flexion increased significantly after of Tai-Chi exercise program. Score of ankle plantar flexion increased significantly after of Tai-Chi exercise program. Score of ankle dorsiflexion increased significantly after of Tai-Chi exercise program. Conclusion: As shown in the results, Tai-Chi exercise program can be effective nursing intervention for osteoarthritis patient to improve joint flexibility.

• 근관절건강학회지
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• 제17권2호
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• pp.151-161
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• 2010

Purpose: The purpose of this study was to identify the effect of Tai Chi exercise on loneliness, sleep pattern, and instrumental activities of daily living in elderly women. Methods: A quasi-experimental design, a nonequivalent control group pretest-posttest was used. Elderly women who agreed to participated in the study were assigned into an experimental group (n=20) or a control group (n=20). The experimental group participated in Tai Chi exercise program (Sun-style 12 forms) for 50 minutes per session, 2 times a week for 8 weeks. Tai Chi exercise program consisted of 10 minutes for warm-up, 35 minutes for main session, and 5 minutes for cooling down. Study outcomes were measured through study questionnaires. Data were analyzed using Chi-square test, t-test and Mann-Whitney test by SPSS WIN 14.0 program. Results: Compared with the control group, the experimental group showed significant improvement in loneliness (t=-2.733, p=.009), sleep pattern (t=2.552, p=.015), and instrumental activities of daily living (z=-2.171, p=.030). Conclusion: Tai Chi exercise program may be an effective nursing intervention for elderly women.

• 컴퓨터교육학회논문지
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• 제8권6호
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• pp.103-111
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• 2005

본 논문에서는 연속된 프레임들의 차이 값으로부터 획득된 평균과 표준편차를 이용한 새로운 자동 임계치-결정 알고리즘을 제안하였다. 먼저, 연속된 프레임사이의 차이 값들에 대한 계산은 기존의 컬러 히스토그램과 ${\chi}^2$-테스트를 병합한 변형된 ${\chi}^2$-테스트 알고리즘을 이용하였다. 변형된 ${\chi}^2$-테스트는 각 컬러공간에 명암도 등급에 따른 가중치를 적용하여 보다 세분화된 값들에 의한 장면전환 검출을 시도할 수 있는 장점이 있다. 제안된 자동 임계치 결정 알고리즘은 획득된 전체 차이값들의 분포로부터 1차 평균과 표준편차를 구한 후, 이를 다시 주어진 차이 값들에 적용하여 1차 평균을 만족하는 차이 값들로부터 2차 평균과 표준편차를 구하며, 이러한 연속적인 평균과 표준편차의 계산으로부터 표준편차가 최대지점으로부터 작아지는 시점의 평균을 기준으로 임계치를 결정하는 방법이다. 제안된 방법은 다양한 비디오 데이터에서 실험되었으며, 실험결과 자동 임계치 결정에 효율적이며, 신뢰할만한 장면들을 검출하였다.