• Journal of the Korean Statistical Society
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• v.23 no.2
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• pp.349-365
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• 1994

We develop in this paper the likelihood ratio test (LRT) for testing $H_1 : F_1 \preceq F_2$ against $H_2 - H_1$ where $H_2$ imposes no restriction on $F_1$ and $F_2$ and '$\preceq$' means failure rate ordering. Both one and two-sample problems will be considered. In the one-sample case, one of the two distributions is known, while we assume in the other case both are unknown. We derive the asymptotic null distribution of the LRT statistic which will be of chi-bar-square type. The main issue here is to determine the least favorable distribution which is stochastically largest within the class of null distributions.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.151-156
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• 2012

In this paper robust nonlinear image denoising algorithms are introduced for the distribution which is Gaussian in the center and Laplacian in the tails. The distribution is known as the least favorable ${\epsilon}$-contaminated normal distribution that maximizes the asymptotic variance. The proposed filter proves to be the maximum likelihood estimator under the heavy-tailed Gaussian noise environments. It is optimal in the respect of maximizing the efficacy under the above noise environment. Another filter for reducing impulsive noise is proposed by mixing with the myriad filter to propose an amplitude-limited myriad filter. Extensive experiment is conducted with images corrupted with ${\alpha}$-stable noise to analyze the behavior and performance of the proposed filters.

• Journal of the Korean Statistical Society
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• v.27 no.2
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• pp.205-220
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• 1998

Dependence concepts for ordered two-way contingency tables have been of considerable interest. We consider a dependence concept which is less restrictive than likelihood ratio dependence and more restrictive than regression dependence. Maximum likelihood estimation of cell probability under this dependence restriction is studied. The likelihood ratio statistics for and against this dependence are proposed and their large sample distributions are derived. A real data is analyzed to illustrate the estimation and testing procedures.

• Communications of the Korean Mathematical Society
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• v.13 no.3
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• pp.629-634
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• 1998

As most of distributions appearing in applications are finite but with the unknown domain of finiteness, we propose to use the robust minimax approach for the determination of the boundaries of this domain. The obtained least favorable distribution minimizing Fisher information over the class of the approximately Gaussian finite distributions gives the reasonable sizes of the domain of finiteness and the thresholds of truncation.

• Journal of Distribution Science
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• v.11 no.2
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• pp.57-70
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• 2013

Purpose - The objective of this paper is to explain the successful methods for the revitalization of distribution and logistics of the least developed FEZs (Saemangum, Yellow-sea, and Deagu-Kyengbuk) in Korea. With the recent changes in the economic terrain of Northeast Asia as with the rise of China, Korea has developed a logistics hub concept for improving the efficiency of logistics and distribution industry and its distribution and logistics policy has received positive worldwide evaluation. Therefore, we face severe competition and must always look for ways to address these problems. Research design, Data, Methodology - This study adopts two methods to propose successful revitalization of distribution and logistics in the least developed FEZ. The first method investigates the limitation of these FEZs by analyzing the statutes, and the second one follows comparable cases. Thus, we first reviewed the efficient strategic political alternatives for the least developed FEZ, Yellow-sea, Seamangum-Gunsan, and Deagu-Kyeongbuk, through the relative institution system, law, and future plans. Next, we studied the Bin-hai Economic Free Section (Zone) in China as a comparable example. In order to analyze the competitiveness of logistics in the three FEZs (Yellow-sea, Seamangum-Gunsan, and Deagu-Kyeongbuk), the total factor productivity growth of regional manufacturing industries is divided into three sources: the external trade effect, scale effect, and technical change effect. However, this paper does not test for a positive contribution of external trade, which is a reason of non-building on these FEZs. A FEZ that shows a larger external trade effect than the others will have a comparative advantage in the logistics infrastructure and policy support. This study presented the newly applied Bin-hai FEZ in China, in order to make the studied FEZ as successful by applying the strategy of its distribution and logistics center. Results - In Korea, there is an increased focus on the benefit of the regional development of regions such as the Free Economic Zones (FEZ). We have six FEZs, Inchon, Busan-Jinhae, Guangyang, Yellow-sea, Seamangum-Gunsan, and Deagu-Kyeongbuk. However, our FEZs do not have various supporting factors needed for the logistics and distribution industry. Korea designated the above six places as FEZ and has operated to enhance national competitiveness and ensure a balanced regional development since 2003. However, most FEZs did not receive favorable feedback in the first business performance evaluation and it is necessary to take action for substantial improvements. Conclusions - Especially, over the past 10 years, even though the FEZ policy has been implemented in an effort to promote success in distribution and logistics, there are still many underdeveloped industries in logistics. The main problem is the absence of revitalization of the high value added performance in the distribution and logistics industry. However, there is a limitation to this study. We have used non-empirical method based on a case study to arrive at our findings. Future studies should use appropriate statistical methods to supplement our results and provide a solution to this problem.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.324-328
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• 1992

The $^1H$ NMR chemical shifts and coupling constants for ${\alpha}$-, permethyl-${\alpha}$-, ${\beta}$-and permethyl-${\beta}$-cyclodextrins in neutral aqueous media were assigned based on the 470MHz spectra. In order to obtain accurate chemical shifts and coupling constants the experimental spectra were analyzed with the Raccoon spin simulation program. The rotamer distribution around the$C_{5-}C_6$ bond of the cyclodextrins evaluated from the coupling constants of $J_{56a}$ and $J_{56b}$. In our calculation of the ${\alpha}$-, and ${\beta}$-cycliodextrin showed that gg conformers were most favorable form and tg conformers were least favorable form. It is very interesting to note the changes in $J_{56a}$, $J_{56b}$ coupling constants of permethylated ${\alpha}$- and ${\beta}$-cyclodextrins from unmodified one. The gg conformers were more increased than unmodified one and instead of tg conformers gt conformers were least favorable one upon methylation.

• Journal of Distribution Science
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• v.22 no.1
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• pp.13-23
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• 2024

Purpose: Within the ever-changing realm of modern e-commerce, this study delves into the complex effects of factors like performance expectations, ease of use, social influence, favorable conditions, and enjoyment perception on users' intentions and usage patterns in online marketplace apps. The research centres on Tokopedia app users in Denpasar City, encompassing a wide and varied demographic. Methods: Utilizing a non-probability sampling method, 200 participants were selected for extensive data collection through surveys. Subsequent rigorous analysis of the gathered data was performed using Structural Equation Modeling-Partial Least Squares (SEM-PLS) techniques. Results: This study aims to contribute substantially to theoretical and practical knowledge regarding marketplace app usage. Theoretical contributions involve enhancing the marketing domain, especially in digital marketing, by revealing the intricate factors influencing user conduct in online marketplaces. From a practical standpoint, this research provides valuable insights for entrepreneurs aspiring to join or improve their positions in the Tokopedia app market. Conclusion: Based on the study, we suggest optimising online shopping apps for a more appealing and user-friendly interface. Enhancing the enjoyment and simplicity of finding desired products can prompt heightened usage of online shopping services, thereby reinforcing distribution management strategies and overall market presence.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.482-491
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• 2007

Statement of problem: The screws of dental implant, having various thread types, can be categorized into different classes by their geometrical form, and each type transmits dissimilar amount and form of stress to alveolar bone. Purpose: The purpose of this study was to find an inclination angle of the screw thread that is favorable in distributing the stresses to alveolar bone. Material and methods: In this study, We used three dimensional finite element analysis with modeling having three types of thread inclination angles and fixed pitch-0.8 mm (single thread type with $3.8^{\circ}$ inclination, double thread type with $7.7^{\circ}$ inclination, triple thread type with $11.5^{\circ}$ inclination). Results: The results obtained from this study were as follows; 1. When the number of thread increased, the amount of Von-Mises stress was reduced since the generated stress was effectively distributed. 2. Since the maximum principal stress affects on the alveolar bone can influence deeply on the longevity of the implants when comparing the magnitude of the maximum principal stress double thread had least amount of stress. This shows that the double thread screw gave best result. Conclusion: In conclusion, double, and triple thread screws were found to be more effective on distribution of the stress than the single thread screws. But, increasing in the thread inclination angle such as triple thread screw relate on the magnitude of the maximum principal stress affecting on the alveolar bone can become problematic. Thus, effective combination of thread number and thread inclination angle can help prolonging the longevity of implant.

• The Journal of Asian Finance, Economics and Business
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• v.3 no.4
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• pp.25-37
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• 2016

This study aims to investigate the determinants of dividend payout of Oil and Gas industry of Pakistan using secondary data from published annual reports from 2008 to 2014 listed on KSE (Karachi Stock Exchange). Dividend payout can be affected by profitability, firm size, financial leverage, sales growth, investment opportunities, liquidity, business risk, and ownership structure. Panel data technique used due to panel characteristics of available data with ordinary least square regression model to find out the impact of set of explanatory variables on the dividend payout using the Stata. Financial leverage, sales growth and business risks are the most significant variables of the study where financial leverage and business risk have significant negative effect on dividend payout while sales growth has favorable positive impact on dividend payout. Results revealed significant positive link of profitability and firm size with dividend payout whereas government ownership is negatively associated with dividend payout. Investment opportunities, liquidity and managerial ownership showed insignificant relationship with dividend payout. This Suggests that dividend payout policy is dependent on business strategies including both investment and financing decisions. Financial managers should consider these factors while formulating dividend policy of the firm.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.329-340
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• 2020

This study investigates the effect of capital structure on the financial performance of pharmaceutical enterprises which are listing on Vietnam's stock market. The study builds the regression using ROE as dependent variable and four independent variables, including self-financing, financial leverage, long-term asset and debt to assets ratios. In addition, we use other variables as controlling ones, such as firm size, fixed asset rate and growth. We collect data for the period from 2015 to 2019 of all 30 pharmaceutical enterprises which are currently listing on Vietnam's stock market. The least square regression (OLS) is used to test the effect of capital structure to the firms' financial performance. The analysis results show that the financial leverage ratio (LR), long-term asset ratio (LAR) and debt-to-assets ratio (DR) have positive relationship with firm performance, meanwhile the self-financing (E/C) affects negatively to the return on equity (ROE). Upon the findings we suggest that the Vietnamese government should focus on stabilizing macro environment to create favorable environment for enterprises. And the pharmaceutical enterprises should build more reasonable capital structure with higher debt proportion than equity, diversifying loan mobilization channels such as issuing long-term bonds. Additionally, the firms should expand the scale appropriately to maintain development and ability to pay debts.