• Communications for Statistical Applications and Methods
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• v.4 no.3
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• pp.903-909
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• 1997

The ordinary least squares estimator and the corresponding pivotal statistics have been widely used for the unit test. Recently several test criteria based on maximum likelihood estimators and weighted symmetric estimator have been proposed for testing the unit root hypothesis in the autoregressive processes. Pantula at el. (1994) showed that the weighted symmetric estimator has good power properties. In this article we use an adjusted estimator for mean in the model when we use weighted symmetric estimator. A simulation study shows that for the small samples, this new test criterion has better power properties than the weighted symmetric estimator.

• Communications for Statistical Applications and Methods
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• v.2 no.1
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• pp.122-136
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• 1995

The objective of this research is to investigate the problem of goodness-of-fit testing based on nonparametric density estimation with a data-driven smoothing parameter. The small and large sample properties of a new test statistic $\hat{\lambda_a}$ is investigated. The test statistic $\hat{\lambda_a}$ is itself a smoothing parameter which is selected to minimize an estimated MISE for a truncated series estimator of the comparison density function. Therefore, this test statistic leads immediately to a point estimate of the density function th the event that $H_0$ is rejected. The limiting distribution of $\hat{\lambda_a}$ is obtained under the null hypothesis. It is also shown that this test is consistent against fixed alternatives.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2096-2098
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• 2002

In this paper, the optimal evasive maneuver strategies for typical subsonic ASM(anti-ship missile) to reach its target ship with high survivability against CIWS(close in weapon system) are studied. The optimal evasive maneuver input is defined by the homing command optimizing the cost function which takes aiming errors of CIWS into account. The optimization problem for the effective evasive maneuver is formulated based on a simple missile dynamics model and a CIWS model. By means of solving the problem, a multiple hypotheses testing method is proposed. Since this method requires generation of too many hypotheses, the hypothesis-pruning technique is adopted. The solution shows that the optimal evasive maneuver is a bang-bane shaped command whose frequency is varied by the aimpoint determination strategy in CIWS.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.504-509
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• 1987

In this paper a characteristics of image which can be segmented based on the thresholding technique using a histogram was investigated employing 3 parameters: the variance of pixel value, the average mean difference between target and background and the target size. The threshold value for the histogram segmentation was determined by applying the hypothesis testing theory. The performance of the selected threshold was evaluated by computing a probability of error. Since a priori probability can be easily obtained from the histogram, it was found that the Bayes decision rule which theoretically guarantees the minimum probability of error works better than the minimax criterion rule.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.3
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• pp.135-149
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• 2007

This paper investigates the relative effect of each ISO 9001 : 2000 quality management system's requirement and business performance. The empirical tests are conducted in ISO 9001 certification companies. As a result, the $1^{st}$, it shows the requirements positively affect performance of financial. The $2^{nd}$, also it shows the requirements positively affect non-financial performance. The $3^{rd}$ also it show the non-financial performance positively effect performance of financial performance.

• Journal of Digital Convergence
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• v.6 no.1
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• pp.75-82
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• 2008

This paper is aimed to exam factors in the perceived service quality of web portal site and to analyze their effects on customer satisfaction. And this paper analysis satisfaction effects on revisit intention. To accomplish this purpose, this study examined previous studies and summarized core factors of service quality. Form literature survey, we drawn core factors. They are convenience, technologies, valuable of contents and service, communication, positioning. These core factors will affect on customer trust, satisfaction and satisfaction will affect on revisit intention. This study examined previous studies and summarized core factor in perceived service quality of web portal site. Fourteenth hypothesis were developed. Data for empirical testing were collected through survey to portal sites user. The results of this study are as follows; First, we find that service, communication and positioning have positive influence on the trust. Second, convenience, valuable of contents and postioning factors have a positive influence on the satisfaction. Third, it is shown that satisfaction have a positive influence on the revisit intention.

• Journal of Veterinary Clinics
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• v.26 no.3
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• pp.189-199
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• 2009

With the growing importance of evidence-based medicine, clinical or biomedical research relies critically on the validity and reliability of data, and the subsequent statistical inferences for medical decision-making may lead to valid conclusion. Despite widespread use of analytical techniques in papers published in the Journal of Veterinary Clinics statistical errors particularly in design of experiments, research methodology or data analysis methods are commonly encountered. These flaws often leading to misinterpretation of the data, thereby, subjected to inappropriate conclusions. This article is the first in a series of nontechnical introduction designed not to systemic review of medical statistics but intended to provide the journal readers with an understanding of common statistical concepts, including data scale, selection of appropriate statistical methods, descriptive statistics, data transformation, confidence interval, the principles of hypothesis testing, sampling distribution, and interpretation of results.

• Honam Mathematical Journal
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• v.31 no.4
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• pp.541-558
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• 2009

Anecdotes can produce an emotional and simple response that decreases stress and anxiety in a classroom. The use of anecdotes in building concepts of statistics can support an effective way of teaching and learning statistics. Particularly, we demonstrate several anecdotes including pictures as the medium of image that are designed to motivate statistical ideas by placing them at the beginning of a lecture and by appealing to prospective teachers weighed down. Our purpose is that under the constructivist view, prospective teachers have an opportunity effectively to teach statistical concepts using humorous anecdotes and to experience significant beliefs on identifying some frequent misconceptions in statistics. At this procedure, the anecdotal teaching practice is concerned with describing and evaluating many humorous anecdotes we have found useful in teaching introductory statistics. We hope that this paper can be helpful to prospective teachers who will teach students such topics as descriptive statistics, sampling, and hypothesis testing.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.215-218
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• 2002

The edges of an image hold much of the information in that image. The edges tell where objects are, their shape and size, and something about their texture. An edge is where the intensity of an image moves from a low value to a high value. We introduce the edge detection using the differential operator with Sobel operator and describe a nonparametric Wilcoxon test based on statistical hypothesis testing for the detection of edges. This paper proposes an efficient edge detection using Van der Waerden's statistic in original and noisy images. We use the threshold determined by specifying significance level a and an edge-height parameter. Comparison with our statistical test and Sobel operator shows that Van der Waerden method perform more effectively in both noisy and noise-free images.

• Journal of Digital Convergence
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• v.7 no.1
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• pp.149-156
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• 2009

Enterprise Resource Planning (ERP) system is one of key information technology to shape doing business. ERP adoption characteristics like IS planning and change management before ERP implementation are rising in importance, because of gaining competitive advantage. The purpose of this study is to analyze the impact of the characteristics of ERP adoption on ERP implementation success. From previous researches on ERP adoption and implementation, two characteristics of ERP adoption such as IS planning and change management, and 2 dependent variables such as process innovation and business performance, are identified. From data collection processes, 122 samples are collected. The results of hypothesis testing show that organizations with IS plan have higher implementation performance than organizations without IS plan. Also, organizations with the process of change management have higher implementation performance than organizations without the process of change management. Also, The interaction effect between IS planning and change management shows bigger impact in ERP implementation success.