• 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.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.77-85
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• 2020

The aim of this study is two-fold. Firstly, it attempts to assess the level of management accounting practices (MAPs) in manufacturing companies in Vietnam. Secondly, it purports to explore the impact of potential contingency factors on the current level of MAPs in the sample of studied companies from the industrial sector in Vietnam. The study examines the hypotheses that MAPs in Vietnamese manufacturing firms are affected by a range of contingent variables. A quantitative research was conducted by sending questionnaires to the target respondents that comprise both accountants and managers in 160 manufacturing enterprises in the north of Vietnam. The first main findings from the study reveal that MAPs in Vietnam are mainly traditional rather than contemporary ones, and oriented toward the short-term rather than the long-term. The second main research findings resulted from multiple regression model show that MAPs in Vietnam are significantly affected by company size, commitment of directors, advanced manufacturing technology, and distinct number of products. However, no significant associations are found between MAPs and intensity of competition from the emerging market as hypothesized in this study. Research findings are bases for recommendations to promote the application of contemporary practices and enhance management accounting functions in manufacturing companies in Vietnam.

• Journal of the Korean Data and Information Science Society
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• v.28 no.6
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• pp.1547-1555
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• 2017

This paper studies Bayesian test of homogeneity in contingency tables made by discretizing a continuous variable. Sometimes when we are considering events of interest in small area setup, we can think of discretization approaches about the continuous variable. If we properly discretize the continuous variable, we can find invisible relationships between areas (groups) and a continuous variable of interest. The proper discretization of the continuous variable can support the alternative hypothesis of the homogeneity test in contingency tables even if the null hypothesis was not rejected through k-sample tests involving one-way ANOVA. In other words, the proportions of variables with a particular level can vary from group to group by the discretization. If we discretize the the continuous variable, it can be treated as an analysis of the contingency table. In this case, the chi-squared test is the most commonly employed method. However, further discretization gives rise to more cells in the table. As a result, the count in the cells becomes smaller and the accuracy of the test becomes lower. To prevent this, we can consider the Bayesian approach and apply it to the setup of the homogeneity test.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.149-155
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• 2004

This paper presents how to find proper operating points of FACTS devices to enhance the steady-state security level considering line contigency analysis. Three generic types of FACTS devices such as series controllers, shunt controllers, and series-shunt controllers are introduced and applied to moximize a security margin and to minimize security indices. Security indices related to line flows and bus voltages are utilized and minimized iteratively in this paper. Contingency analysis is performed to detect the most severe single line fault. In various load conditions, FACTS devices are tested to establish appropriate preventive or corrective action without generation re-dispatching or load shedding. The FACTS operation scheme is verified on the IEEE 57-bus system in a line-faulted contingency.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.325-340
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• 2019

The purpose of this paper is to develop and suggest an integrative leadership contingency framework of leadership that will state the situational and psychological factors under which leadership effect should be maximized. Our leadership model presents that situational factors, including development, circumstances urgency and task structure, proposes which of transformational, transactional, empowering, and authentic leadership solutions. Also, our integrative leadership contingency model in turn results in a combination of the level of follower commitment, intrinsic motivation, and individual creativity based on inductive research method. This integrative leadership model suggested here has significant contributions for leadership effectiveness and future leadership research agenda. Next leadership research could experimentally examine the structural relationships between each of the leadership styles and levels of contingency and psychological factors of followers.

• Communications for Statistical Applications and Methods
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• v.5 no.3
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• pp.905-926
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• 1998

We propose a modified mid P-value method to reduce the conservativeness for the inference of conditional associations in three-way contingency tables. This improves the ordinary mfd P-value method. For $2{\times} 2${\times} K$ tables, we propose confidence intervals for an assumed common odds ratio based on inverting two separate one-sided tests using the modified mid P-value. Also, an alternative and usually even better ways of constructing intervals, based on Inverting a two-sided test, are presented. The actual probability of coverage of a 100($1-\alpha$)% confidence interval is centered about the nominal level, but the modified mid P-value approach gives actual coverage probability even closer to the nominal level than the ordinary mid P-value approach.

• Journal of Information Technology Applications and Management
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• v.23 no.3
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• pp.71-86
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• 2016

This paper proposes a new software quality model composed of a hierarchy of software quality views and three software quality characteristics models. The software view hierarchy is composed of two levels : end view and means view at the first level, contingency view and intrinsic view as sub-views of means view. Three software quality characteristics models are activity quality characteristics model, contingency quality characteristics model, and intrinsic quality characteristics model, which correspond to end view, contingency view, and intrinsic view respectively. This paper also reclassifies characteristics of ISO/IEC 25000 series SQuaRE's software product quality model according to the proposed software quality model. The results illustrate clearly the shortcomings of SQuaRE's product quality model and how to overcome them. First of all, most of SQuaRE's product characteristics should be redefined and conceptually clarified according to the views on which they are really rested. Much more characteristics should be supplemented too. After that, rigorous empirical researches will become relevant. Causal relationships between activity quality characteristics and characteristics of means view should be empirically researched.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.1
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• pp.36-42
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• 2011

This paper mainly proposes the protective coordination scheme of the microgrid system. The microgrid protection is identical to the conventional protection system separating the normal part and contingency part to reduce damage when the contingency occur at power cables, facilities. But they are different in the protection type. The conventional protection system only considers unidirectional current. However the microgrid protection should be considered not only unidirectional current but also backfeed current because various microsources and loads are installed in the microgrid system. In case the contingency occurs in microsource, when microgrid is interconnected to grid, the protection system should be configured to not separate microgrid from grid before the microsource is isolated to microgrid. And in case of fault occur in power system, the microsources should not isolated to microgrid before the static switch at PCC is tripped to separate from power system. Considering these characteristic of microgird, this paper proposes the protective coordination scheme of microgrid and implemented the on-line real time monitoring system. Especially in case the microgrid is connected to low voltage distribution system with 220/380V voltage level, the proposed protection method with power IT technology can solve the problems when the existing protective devices only applied to the microgrid system.

• Journal of the Korean Statistical Society
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• v.25 no.4
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• pp.489-497
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• 1996

Lower bounds for the full level probabilities are derived under order restrictions in weights. Discussions are made on typical isotonic cones such as linear order, simple tree order, and unimodal order cones. We also discuss applications of these results for constructing conditional likelihood ratio tests for ordered hypotheses in a contingency table. A real data set on torus mandibularis will be analyzed for illustrating the testing procedure.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.1
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• pp.125-134
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• 2011

The research is a survey and analysis of female apparel preferences, and recognition of the KS sizing system for adult female garments. The practical surveys in this research are examined by total number of subjects, 200 women who are living in Seoul, South Korea. The homogeneity test using Chi-square statistics, and the analysis of frequencies and ratios of contingency tables were performed with the data which are classified by age, education level, income level and housing modalities. The findings in this study are as follows: 1. Women's preferences for purchasing female garments indicate significant differences between subjects, such as age, education level, income level and housing modalities. Moreover, the following five types of adult female garments were analyzed in this study: upper garment, lower garment, one-piece apparel, sportswear and sleepwear. The results of the preference study show an indirect understanding of the KSK 0051 classification system for subjects of the survey. Therefore the preference study can be used as a pilot study for the sizing recognition survey. 2. Women's recognition of the KSK 0051 sizing system for adult female adult garments do not indicate significant differences based on the characteristics of age, education level, income level and housing modalities. The low recognition of the KS sizing system is due to too many details and complex numbers of application for users. Therefore, the sizing system should be simplified and rearranged to be more effective and have more recognizable categories.