• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.10
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• pp.27-36
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• 2014

Network analysis applications in energy management systems play a key role in the economic and reliable operation of power systems. In order to provide operators with useful network information, the accurate results of topology processing, state estimation, power flow, and contingency analysis must be simulated. This paper proposes a validation methodology of network analysis applications in energy management systems. The energy management systems was checked to ensure that it meets the originally specified functions based on the proposed methodology. In addition, the performance of state estimation is evaluated with the reference of the proposed methodology. The proposed methodology is being conducted by energy management systems and the Korean power systems have been utilized for the test systems.

• Knowledge Management Research
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• v.9 no.1
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• pp.23-38
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• 2008

This study develops a framework and instruments to diagnose the current knowledge management(KM) status of an organization and to suggest future KM implementation directions. Based on the comprehensive review of KM literature and KM case studies, we derive three main aspects(strategic, social and technical aspect) and seven critical factors(KM strategy, knowledge worker, organizational strucuture, organizational culture, KM processe, organizational knowledge, and information technology) for the successful KM implementation. The instruments developed in this study include every specific measurement items of each critical success factor, which are expected to help not only suggest a context-sensitive KM strategy but also evaluate current KM status of a designated organization. By introducing two dimensions of KM evaluation(effectiveness and necessity), a more holistic and contingent view of KM can be assured. Academic contributions as well as practical implications are discussed. Study limitations and future research directions are also provided.

• Communications for Statistical Applications and Methods
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• v.3 no.2
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• pp.69-76
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• 1996

In a two-way contingency table, the analyst is most interested in the hypotheses of either homogeneity or independence. For testing this as a null hypothesis, Pearson's ${\chi}^2$ statistic is most commonly used in practice. Once the null Hypothesis is rejected, he will further search forcells which caused the rejection of the null hypothesis. For this purpose, so called cell${\chi}^2$ components are used. In this paper, we derive the influence function of an obsevation to the ${\chi}^2$ statistic, with which cells with high influence can be identified.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.4
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• pp.208-213
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• 2018

In this paper, we studied the control strategy of applying STATCOM(static synchronous compensator) to mitigate the FIDVR(fault induced delayed voltage recovery) phenomenon. The proportion of motor loads is gradually increasing which might affect power system stability. Excessive reactive power consumption by the stall of the motor loads causes FIDVR phenomenon. In addition, the low inertia of the small HVAC(heating, ventilation and air conditioner) unit will not separate itself in the event of a contingency, causing system instability. For this reason, we have developed a control strategy that utilizes STATCOM efficiently through static and dynamic analysis. Case studies on a Korean power system have validated the performance of the proposed scheme under severe contingency scenarios. The results have verified that the proposed strategy can effectively mitigate FIDVR and improve the stability and reliability of the system.

• The Journal of Society for e-Business Studies
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• v.20 no.2
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• pp.167-174
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• 2015

Information security organization has normally been organized under the IT department. However, as the importance of information security has gradually increased, the way of information security organized for enterprise security management has become a noteworthy issue. The need for separation of Information security organization from IT department is growing, such as restriction on the concurrent positions in CIO and CISO. Nowadays there are many studies about Information security organization while relatively there has been minimal research regarding a departmentalization. For these reasons this study proposes a Information Security Departmentalization Model which is based on business risk and reliance on the IT for effectively organizing Information security organization, using Contingency theory. In addition, this study classified the position of Information security organization into Planning & Coordination, Internal Control, Management and IT and analyze the strengths and weaknesses of each case.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.5
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• pp.841-846
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• 2010

Reliability in electrical power system refers to normal operation for schedule time in some system that action consists. It means that if there is no contingency of electric power supply decrease or load curtailment, reliability of the system is high. In this paper, a method for evaluation of transmission capability is proposed considering reliability standards. Deterministic and probabilistic methods for evaluation of transmission capability has been studied. These researches considered uncertainty of system components or N-1 contingency only. However, the proposed method can inform customers and system operators more suitable transmission capability. Well-being method using state probabilities of system components proves to be a more effective method in this paper comparing with calculation of LOLE(Loss of Load Expectation). The length of calculation is shorter but it can give more practical information to the exact system operators. Well-being method is applied to IEEE-RTS 24bus system to evaluate reliability in case study. The result is compared with a existing way to evaluate reliability with LOLE and it shows that transmission capability connected with adjacent networks. This paper informs system operators and power suppliers of reliable information for operating power system.

• The Korean Journal of Applied Statistics
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• v.17 no.1
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• pp.89-103
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• 2004

If the given information is exact, though it is the little, we had better use it than not use in analysis. In this article, the problem of independence test in a contingency table is considered when two marginal distributions of a population are given exactly. For that case, a likelihood-ratio chi-squared test statistic and its Pearsonian type chi-squared test statistic are derived. By Monte Carlo Simulations the traditional chi-square tests and the derived tests are compared. And the related some testing problems are synthetically explained on a geometrical viewpoint.

• Management & Information Systems Review
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• v.2
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• pp.47-73
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• 1998

According to the structural contingency theories, organizational structures are determined by such a contingency variables as organizational environment, technology, size, power and strategy. Therefore, many scholor believed that organizational effectiveness will be maximized in the condition of the fit between organizational structure and its contingency variables. But contingency theories have limitations in explaining of the manager's discretion by way of environmental determinism. In 1972, Child introduced strategic choice theory, and this perspective spurred significant, systematic studies of the influence of the managerial voluntary will on the organizational performance. Especially, the question of whether tap managers have an impact on business performance has been addressed by the strategic leadership theory that demonstrates strong associations between the characteristics of top managers, strategic orientation. Therefore, this study has investigated a theoretical literature and an empirical survey that explains the impact of top manger characteristics and organizational characteristics about strategic orientation. In order tn do that, this study develops a research model on the subjects, designed manager's characteristics, strategic typology. Managerial characteristics could be operationalized in terms of demographic measures. In this study, strategic orientation was classified using the Miles & Snow typology. This research model provides hypotheses. Hypotheses H1: The demographic characteristics of the tap manager will differ according to the types of strategic types. H2: The organizational characteristics of the firm will differ according to the types of strategic types. To test these hypotheses, this study conducted questionaire surveys on 108 firms in the Korea national wide. This study has utilized ANOVA, Chi-square analysis, cluster analysis, discriminant analysis for testing the hypotheses. The major findings of this study are summarized as follows. First, this study builds on the central tenent of cotingency theory in provide a comprehensive explanation of the process by which top manager's influence. Second, Manager's characteristics(demographics) are different from each other according to 4 strategic types(Prospector, Defender, Analyzer, Reactor). Third, Organizational characteristics are different from each other according to 4 strategic types. In conclusion, the major contributions of this study are to examine the development of a more comprehensive theoretical framework in the strategic leadership theory and to analyze their contingent relationships among managerial characteristics, organizational characteristics and strategic types in the context of Korea's industry.

• Information Systems Review
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• v.4 no.2
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• pp.81-94
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• 2002

The study employs the conceptual framework of the strategic success paradigm developed by Ansoff (1990). The strategic success paradigm denotes that optimal performance will be attained when the level of environmental turbulence is aligned with the strategic aggressiveness and organizational capability. Based on the paradigm, authors developed the concept of IT (information technology) aggressiveness (IT aggressiveness henceforth) and capability (IT capability henceforth). In order to clarify the different concept of IT aggressiveness and capability, the author brought the concept of IT architecture. The difference of capability and architecture lies in the depth of technical considerations. Where capability refers attitudinal aspects of managers, architecture emphasizes technical capacity of the organization as a whole. The study validated the need for alignment among IT architecture, environmental turbulence and IT aggressiveness. The imbalance between IT strategy and IT architecture (such as a higher level of IT aggressiveness but a lower level of IT architecture, or vice versa) has a marginal contribution to the organizational IT performance. The alignment among organizational environmental turbulence, IT aggressiveness, and IT architecture resulted in an optimal level of IT performance especially in a turbulent environment.

• Communications for Statistical Applications and Methods
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• v.11 no.2
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• pp.419-433
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• 2004

We suggest the modified computing algorithm for raking ratio estimation under the assumption that the population total is partially known, and the sample total is completely known about survey variable in contingency table. We show that the proposed estimation procedure is useful to estimate the population cell count in this situation through an empirical study.