• 한국멀티미디어학회논문지
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• 제19권8호
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• pp.1386-1394
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• 2016

Pyramid fusion usually adjusts the Laplacian weights of pixels of the input images by evaluating predefined criteria. This has advantages that it can selectively express intense color and enhance the contrast when applied to HDR exposure fusion. But it may cause noise because the weights are determined by pixel importance without considering the interdependent pixel relationship that constitutes a scene. This paper proposes a fusion method using simple weight criteria generated from the gray pixel values, which is expected to preserve the interdependent relationship and improve execution speed. In order to evaluate the performance of the proposed method we examine a homogeneity measure, H and compare the execution time for both methods. The proposed method is found to be more advantageous with respect to homogeneity and execution speed.

• 한국초전도ㆍ저온공학회논문지
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• 제23권4호
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• pp.39-43
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• 2021

This study deals with the ferromagnetic shims design based on the spherical harmonic coefficient reduction method. The design method using the sequential search method is an intuitive method and has the advantage of quickly reaching the optimal result. The study was conducted for a 400 MHz all-REBCO magnet, which had difficulty in shimming due to the problem of SCF (screening current induced field). The initial field homogeneity of the magnet was measured to be 233.76 ppm at 20 mm DSV (Diameter Spherical Volume). In order to improve the field homogeneity of the magnet, the ferromagnetic shim with a thickness of 1 mil to 11 mil was constructed by a design method in which sequential search algorithm was applied. As a result, the field homogeneity of the magnet could be significantly improved to 0.24 ppm at 20 mm DSV and 0.05 ppm at 10 mm DSV.

• Advances in concrete construction
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• 제11권4호
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• pp.315-321
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• 2021

In this article, an analytical solution of the dynamical behavior in an orthotropic non-homogeneity elastic material using for elastodynamics equations is investigated. The effects of the magnetic field, the initial stress, and the non-homogeneity on the radial displacement and the corresponding stresses in an orthotropic material are investigated. The analytical solution for the elastodynamic equations has solved regarding displacements. The variation of the stresses, the displacement, and the perturbation magnetic field have shown graphically. Comparisons are made with the previous results in the absence of the magnetic field, the initial stress, and the non-homogeneity. The present study has engineering applications in the fields of geophysical physics, structural elements, plasma physics, and the corresponding measurement techniques of magneto-elasticity.

• 한국지방자치학회보
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• 제25권1호
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• pp.91-116
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• 2013

The purpose of this paper is to find out the set of the factors influencing on the successful voluntary consolidation among local governments. This paper considers the voluntary consolidation as a kind of coordination mechanism and institutional collective action process between local governments, and identifies the configurations of the causal factors influencing the voluntary consolidations by applying the fuzzy-set analysis. It is found that the sets of the causal factors which include political and economic homogeneity factors in the region, and interlocal political, economic, and social homogeneity factors, and prior consolidation experience between regions have positive effects on the consolidations. Also, it turns out that interlocal homogeneity and conformity between regions should be considered significantly for institutionalization which supports the consolidation between local entities.

• 정보처리학회논문지B
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• 제17B권5호
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• pp.363-374
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• 2010

본 논문에서는 영상의 동질성 영역 분할을 위한 동질성 문턱 값(Homogeneity Threshold: $H_T$)의 자동 추출과 USRG(Unseeded Region Growing) 기반의 동질성 영역 자동 분할 방법을 제안한다. $H_T$는 인접한 화소들 간에 동질성을 구분하는 기준이 되며, 제안한 방법에 의하여 원본영상으로부터 자동 계산된다. 제안한 방법의 이론적 배경은 Otsu의 단일수준 문턱 값(single level threshold) 방법인데, 이것은 원본 영상의 작은 국소영역을 두 클래스로 분할하기 위하여 사용되고, 두 클래스가 서로 다른 영역으로 구별되는 조건을 만족할 때의 각 클래스의 표준편차의 합($\sigma_c$)을 $H_T$를 계산하기 위한 요소로 사용한다. 제안한 방법의 타당성을 보이기 위해 분할된 동질성 영역들만을 가지고 새롭게 생성한 영상과 원본 영상과의 비교를 통해 시각적으로 차이가 없음을 보이고, 분할된 동질성 영역의 크기순과 화소수가 많은 명암도 순으로 분할된 영역들을 결합한 영상들과 자동 추출된 문턱 값($H_T$)에 범위조정계수 ${\alpha}$을 적용한 값($H^*_T$)를 가지고 분할한 결과 영상들의 제시를 통해 제안한 방법에 대한 타당성을 보였다. 제안한 방법은 해부학이나 생물학의 연구 및 자연 영상의 시각화와 애니메이션 등 다양한 분야에서 활용될 수 있으리라 기대한다.

• 대한간호학회지
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• 제28권4호
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• pp.941-957
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• 1998

The purpose of this study was to use meta-analysis to analyze result of 17 studies which investigated the effects of integrated programs, and 11 studies which examined the effects of exercise programs on pain, depression, and disability. The 28 studies analyzed in this work were selected from the following sources. MEDLINE Search, bibliographies of related studies, main academic journals of nursing in Korea, and journals on arthritis issues. For the analysis of the data, homogeniety of effect sizes which were calculated based on data in the 28 studies was tested and its average effect size was computed by using meta analysis software package which was developed by Song(1992, 1998). The results can be summarized as follows : 1) Homogeneity tests were conducted on integrated programs on pain. In the prelimiary homogeneity tests on effect size of all 17 studies, no homogeneity was found. When homogeneity tests on the effect size of the remaining 15 studies were performed, excluding two studies which had extremely larger effect size compared to other studies, the 15 studies were found to be homogeneous(Q=16.38, p=.23). The obtained average effect size, D(Mean Standardized Difference Between Means), was .25. When homogeneity tests on effect size on pain was conducted for the excercise programs, effect size for all nine studies were found to be homogeneous (Q=7.42, p=.49) and the average effect size D=.30. Therefore, Hypothesis 1 was rejected from the results, that an average effect size of the integrated programs on pain was not significantely different from that of the exercise programs on pain. 2) Since only two studies investigated the effect of exercise programs on depression, comparison between the average effect size of integrated programs and that of exercise programs on depression could not be conducted, and hypothesis 2 could not be tested. Thereby, only the average effect size of integrated programs on depression was obtained. Eight studies were tested to be positive on the homogeneity of effect sizes(Q=18.31, p=.02) at $\alpha$<.01 and its average effect size was D=.11. 3) For the analysis of integrated program on disability, 13 studies, except for four which had an extremely large effect size compared to the others were found to be homogeneous at $\alpha$<.01 (Q=22.30, p=.04) and the average effect size on disability was D=.16. For analysis of the exercize programs on disability, eight studies, except for one which had an extremely large effect size compared to others, were found to be homo geneous(Q=7.87, p=.34) and the average effect size on disability was D=.60. Therefore, Hypothesis 3 was accepted from the results that an average effect size of exercise programs on disability was significantly larger than that of integrated programs on disability.

• Communications for Statistical Applications and Methods
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• 제9권3호
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• pp.853-864
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• 2002

In the analysis of categorical data subject to misclassification errors, the observed cell proportions are adjusted by a misclassification probabilities and estimates of variances are adjusted accordingly. In this case, it is important to determine the extent to which misclassification probabilities are homogeneous within a population. This paper considers methods to evaluate the power of chi-squared tests for homogeneity with complex survey data subject to misclassification errors. Two cases are considered: adjustment with homogeneous misclassification probabilities; adjustment with heterogeneous misclassification probabilities. To estimate misclassification probabilities, logistic regression method is considered.

• Journal of the Korean Data and Information Science Society
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• 제21권1호
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• pp.163-172
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• 2010

In this paper, we deal with the problem for testing homogeneity of coecients of variation in several normal distributions. We propose Bayesian hypothesis testing procedures based on the Bayes factor under noninformative prior. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be dened up to a multiplicative constant. So we propose the objective Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference prior. Simulation study and a real data example are provided.

• Korean Journal of Mathematics
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• 제22권3호
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• pp.407-417
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• 2014

We present some proofs of the classical integral Hardy inequality. Our approach makes use of continuous functions with compact support in (0, ${\infty}$), homogeneity of the norm and Schur's criterion for integral operators.

• Journal of the Korean Statistical Society
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• 제34권3호
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• pp.185-195
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• 2005

This article is concerned with the intraclass correlation in survey sampling. From a design-based viewpoint the intraclass correlation is generalized to a finite population with unequal sized clusters. Under simple random cluster sampling the intraclass correlation is given in an explicit form, which is a generalization of the usual one. The range of it is found and the design effect is expressed by means of it. An example is given to compare the intraclass correlation with the homogeneity measure numerically, which shows that two measures are not the same except some limited cases.