• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.1
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• pp.85-98
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• 1994

The distribution of random sum of i. i. d. exponential random variables is called GHP (Generalized Phase-Type) distribution. The class of GPH distributions is large enough to include PH (Phase-Type) distributions and has several properties which can be applied conveniently for computational purposes. In this paper, we show that any distribution difined on R$^{+}$ can be app-roximated by the GPH distribution and demonstrate the accuracy of the approximation through various numerical examples. Also, we introduce an efficient way to compute the delay and waiting various numerical examples. Also, we introduce an efficient way to compute the delay and waiting time distributions of the GPH/GPH/1 queueing system which can be used as an approximation model for the GI/G/1 system, and validate its accuracy through numerical examples. The theoretical and experimental results of this paper help us accept the usefulness of the approximations based on GPH distribution.n.

• Communications for Statistical Applications and Methods
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• v.7 no.1
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• pp.225-232
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• 2000

The linear and quadratic discrimination functions based on normal theory are widely used to classify an observation to one of predefined groups. But the discriminant functions are sensitive to outliers. A high breakdown procedure to estimate location and scatter of multivariate data is the minimum volume ellipsoid or MVE estimator To obtain high breakdown classifiers outliers in multivariate data are detected by using the robust Mahalanobis distance based on MVE estimators and the weighted estimators are inserted in the functions for classification. A samll-sample MOnte Carlo study shows that the high breakdown robust procedures perform better than the classical classifiers.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.1045-1054
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• 1996

Tissue culture, or micropropagation , is being used for the vegetative multiplication of several hundred millions of superior plants annually for horticulture and forestry. It is often more expensive than other forms of propagation using cuttings or seeds, because it is labor intensive and more specialized . The aim of automation is to reduce the cost per plantlet by reducing labor input, and finally, to yield profit, as business activity . Labor usually account for 70-80% of th ein vitro and ex vitro cost. This paper aspects of tissue culture automization , such as technical and economical approaches in view of automization.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.1
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• pp.148-155
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• 2014

The purpose of this research was to analyze the effects of smart learning. By using meta analysis method, twenty MA and Ph.D degree papers published from 2006 to 2013 were analyzed and 104 effect sizes were calculated. Followings were the results of the research: (a) Smart learning turned out to be more statistically effective comparing to traditional education. The total mean effect size was .886 and the value of U3 was 66.53%. (b) All effect size of sub dependent variables(ie, academic achievement, learning satisfaction, learning attitude) were also effective by adapting smart learning. (c) The moderated variables likes learner characteristics, learning content, and interaction had high effect sizes. Operation system variable had a low effect size but it was not significant.

• Communications for Statistical Applications and Methods
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• v.4 no.3
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• pp.833-845
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• 1997

Fourier expansion is considered for the deconvolution problem of estimating a probability density function when the sample observations are contaminated with random noise. In the log-Fourier method of density estimation for data without noise, the logarithm of the unknown density function is approximated by a trigonometric function, the unknown parameters of which are estimated by maximum likelihood. The log-Fourier density estimation method, which has been considered theoretically by Koo and Chung (1997), is studied for the finite-sample case with noise. Numerical examples using simulated data are given to show the performance of the log-Fourier deconvolution.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.97-102
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• 2002

Life Science Research Center of SK Chemicals has developed a 3rd-generation anticancer platinum drug for the first time in the nation′s 100-year-old pharmaceutical industry. The Korea Food and Drug Administration (KFDA) approved the sale of "Sunpla" (code name SKI 2053R, general name : Heptaplatin) on July 14, 1999 for the treatment of advance, metastatic gastric cancer. Cisplatin, the 1 st-generation anticancer drug, which was developed by Bristol-Myers of the United States in 1976, is one of the most potent anticancer drugs and is a major component of combination chemotherapy for a variety of human cancers. However its clinical usefulness has frequently been limited not only by undesirable side effects such as severe renal toxicity, nausea, vomiting, ototoxicity, and neurotoxicity but also by the development of resistance. Carboplatin, the 2nd-generation anticancer platinum drug, which was also developed by Bristol-Myers in 1986, has modified the problems of the renal and gastrointestinal toxicities of cisplatin. Carboplatin, however, has no enhanced therapeutic efficacy over cisplatin and does not possess the property to overcome cross-resistance to cisplatin.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.263-266
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• 2001

본 연구는 전력품질을 평가할 수 있는 DSP기반 3상 전력품질 분석장치의 국산화 개발을 목표로 하고 있다. 전력분석 알고리즘은 시간영역의 간단한 평균전력이론을 사용하였고, 독립형 TMS320C31 DSP 보드에 의해 전력을 실시간으로 분석하여 LCD와 D/A 변환기로 출력하였다. 2PH의 모터와 그 구동장치 (인버터)의 전력품질을 분석함으로서 외국산 제품과 비교하여 그 성능과 정밀도 등을 검토하였다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.1 no.2
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• pp.1-15
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• 1995

Almost of all impediments to enhancing ship safety and preventing vessel-source marine pollution arise from the interaction between direct and indirect factors. The direct factors come from human errors and failure in compliance with the international convention standards for the operation of cessel. The indirect factors derive from the will and attitudes of the countries taking little responsibilities with appropriate seriousness for policing their fleets. By focusing on these aspects, this paper reviews the effectiveness of existing countermasures adopted by IMO and intends to propose a new paradigm to improve the implementation capability of each nation by suggesting frameworks of maritime administration models.

• Asian review of World Histories
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• v.1 no.1
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• pp.117-149
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• 2013

The purpose of this essay is threefold. First, to highlight research of Seonmin KIM, whose 2006 Ph.D. dissertation elucidates complex relationships among Ming China, Choson Korea, Tokugawa Japan, and mountainous ginseng-producing "borderlands" between Korea and China; her story concludes with the remarkable rise of a borderlands power that overthrew Ming China, there-by establishing dominance that lasted into the $20^{th}$ century - the Qing Dynasty. A second purpose is to showcase application of a non-standard-model - the Hydraulic Metaphor - that elucidates economic components of Professor KIM's history via visual and intuitive mechanisms designed to be understandable for non-specialists. Last, an outline of East Asian history is placed within context of centuries of monetary evolution that eventually yielded the late-$16^{th}$-century birth of globalization.

• Asian Journal of Innovation and Policy
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• v.3 no.1
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• pp.72-93
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• 2014

This study analyzed the factors that influence the research productivity of 236 graduate students who are funded by the Global Ph.D. Fellowship Program of the National Research Foundation of Korea. Research productivity was measured by the number of SCI publications, and the explanatory factors are the demographic factor, the financial factor, the reputation of institutions and the supervisor factor. This study included 2 indices such as the reputation of institutions and the research productivity of supervisors to check the halo effect unlike other studies. Results are as follows: 1) no gender difference, 2) better performance by younger age group, 3) no difference even if the students are additionally funded by other research support programs, 4) no halo effect by the reputation of institution but rather better performance from low ranked universities, 5) and a positive halo effect by supervisors.