• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.77-85
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• 2015

In this paper, we present a new method that can detect forged color region using color pattern decomposition and hypothesis testing approach. On the basis of the fact that the variance of the interpolated pixel is smaller than that of the original pixel, we use a statistical test method to judge the statistical inconsistency of variance. For this, we calculate the variance adopting a color pattern decomposition according to the demosaicking pattern. In addition, we apply high-pass filtering to enlarge the difference between the variances of original and interpolated pixel. Through experimental simulations, we can see that our proposed method can effectively detect forged color regions and shows superior detection performance compared to the conventional method.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.5
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• pp.365-372
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• 2019

We propose a method to estimate unknown parameters(e.g., target amplitude and clutter parameters) in the generalized likelihood ratio test(GLRT) using maximum likelihood estimation and the Newton-Raphson method. When detecting targets in a clutter environ- ment, it is important to establish a modular model of clutter similar to the actual environment. These correlated clutter models can be generated using spherically invariant random vectors. We obtain the GLRT of the generated clutter model and check its detection probability using estimated parameters.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.3
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• pp.147-153
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• 2004

This paper proposes an efficient edge detection using Van der Waerden statistic in original and noisy images. An edge is where the intensity of an image moves from a low value to a high value or vice versa. We describe a nonparametric Wilcoxon test and a parametric T test based on statistical hypothesis testing for the detection of edges. We use the threshold determined by specifying significance level $\alpha$, while Bovik, Huang and Munson consider the range of possible values of test statistics for the threshold. From the experimental results of edge detection, the T and Wilcoxon method perform sensitively to the noisy image, while the proposed Waerden method is robust over both noisy and noise-free images under $\alpha$=0.0005. Comparison with our statistical test and Sobel, LoG, Canny operators shows that Waerden method perform more effectively in both noisy and noise-free images.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.859-867
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• 2016

Bunker oil is an essential expense, and it is a high cost in ships' operations. Therefore, it forms an important part of the work shipowners do to minimize losses during operations. With bunkering disputes consistently occurring, bunker surveyors could be employed by shipowners through them and bunker survey companies signing a contract for a bunker surveyor service. Bunker surveyors could play the role of independent contractors and issue statements of fact in relation to bunkering. However, it would be impossible for bunker surveyors to immediately resolve a bunkering dispute since their role and the legal status is not clear while bunker surveys are being conducted on ships. Thus, this study sets out to define the legal status and liability of bunker surveyors and to seek an additional role for them when bunkering disputes occur.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2813-2827
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• 2018

Progressive censoring schemes have become quite popular in reliability study. Under progressive censored data, however, some units can be failed between two points of observation with exact times of failure of these units unobserved. For example, loss may arise in life-testing experiments when the failure times of some units were not observed due to mechanical or experimental difficulties. Therefore, multiply progressive censoring scheme was introduced. So, we derives a maximum likelihood estimator of the parameter of exponential distribution. And we introduced the goodness-of-fit test statistics using order statistic and Lorenz curve. We carried out Monte Carlo simulation to compare the proposed test statistics. In addition, real data set have been analysed. In Weibull and chi-squared distributions, the test statistics using Lorenz curve are more powerful than test statistics using order statistics.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.87-92
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• 2017

The Samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Platygasteridae) is recognized as a solitary parasitoid on eggs of the stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an economic pest causing severe damage to fruits, in South Korea. The wasp appears to be a potential biological agent of the pest. In addition, T. itoi Ryu and T. nigripedius (Nakagawa) were found to parasitize eggs of Eurydema gebleri Kolenati and Dolycoris baccarum Linnaeus, respectively. Diagnostic characters and photographs are provided for identification, and host records of Korean Trissolcus species are also given.

• Journal of the Korean Data and Information Science Society
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• v.21 no.6
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• pp.1243-1251
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• 2010

For clinical trials, it is common to compare the placebo and new drug. The method of calculating a sample size for two independent populations are the t-test that is used for parametric methods, and the Wilcoxon rank-sum test that is used in the non-parametric methods. In this paper, we propose a method that is using Kim's (1994) statistic power based on the linear placement statistic, which was proposed by Orban and Wolfe (1982). We also compare the sample size for the proposed method with that for using Wang et al. (2003)'s sample size formula which is based on Wilcoxon rank-sum test, and with that of t-test for parametric methods.

• The Korean Journal of Applied Statistics
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• v.28 no.2
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• pp.189-200
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• 2015

Stationary bootstrapping is applied to a Lagrangian multiplier (LM) test to test market microstructure noise (MMN) in financial asset prices. A Monte-Carlo experiment shows that the bootstrapping method improves the size of the original LM test which has some size distortion for conditional heteroscedastic models. The proposed test is illustrated for real data sets like KOSPI index and Won-Dollar exchange rate.

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.124-127
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• 2008

A new orange-colored, cut flower gerbera (Gerbera hybrida Hort.) cultivar 'Sweety' was developed from a cross between 'Grandeur' and 'Songsongee', followed by selections of seedlings and lines at the Flower Breeding Research Institute, Gyeongnam Agricultural Research and Extension Services (ARES) from 1999 to 2004. Three time evaluations were conducted from 2003 for the detailed characteristics of the new cultivar. 'Sweety' has semi-double type mini- or medium-sized flowers in good harmony with orange(RHS, 38-A) ray florets and a green center. It has good, stable flower shape and strong peduncle, and its vase life was 10.4 days. The average flower yield was about 51.0 stems per plant/year in greenhouse trails during 2003 and 2004. This cultivar was registered to the Korea Seed and Variety Service for commercialization in 2006. Year-round production of this cultivar is possible in the greenhouse condition in Korean climate.

• Korean Journal of Breeding Science
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• v.40 no.1
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• pp.80-83
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• 2008

A new pink gerbera (Gerbera hybrida Hort.) cultivar 'Summer Ring' was developed from a cross between 'Grandeur' and 'Nova Zembla' followed by seedling and line selections at the Flower Breeding Research Institute, Gyeongnam Agricultural Research and Extension Services (ARES) in 2005. Characteristics of the new cultivar were evaluated three times from 2003 to 2004. 'Summer Ring' has semi-double type mini flower in good harmony with pink (RHS, 56-D) ray floret and green center. It has good stable flower shape and strong peduncle, and its vase life was 14.7 days. The average yield of 'Summer Ring' flower was 69 per plant/year in greenhouse yield trails during 2003 and 2004. This cultivar was registered for commercialization in 2005. Commercial production of 'Summer Ring' could be possible throughout the country under greenhouse condition.