• The Korean Journal of Applied Statistics
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• v.16 no.1
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• pp.55-69
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• 2003

In this article, we propose the weighted LAD (least absolute deviations) estimators for multi-dimensional contingency tables and drive an estimation method to estimate the proposed estimators. To illustrate the robustness of the estimators, simulation results are presented for several models Including log-linear models and models for ordinal variables in multidimensional contingency tables. Examples were also introduced.

• KIEE International Transactions on Power Engineering
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• v.2A no.4
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• pp.131-135
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• 2002

This paper describes a new ultra-fast contingency screening algorithm for on-line TSA without time simulation. All machines are represented in a classical model and the stability index is defined as the ratio between acceleration power during a fault and deceleration power after clearing the fault. Critical clustering of machines is done based on the stability index, and the power-angle curve of the critical machines is drawn assuming that the angles of the critical machines increase uniformly, while those of the non-critical ones remain constant. Finally, the critical clearing time (CCT) is computed using the power-angle curve. The proposed algorithm is tested on the KEPCO system comprised of 900-bus and 230-machines. The CCT values computed with the screening algorithm are in good agreement with those computed using the detailed model and the SIME method. The computation time for screening about 270 contingencies is 17 seconds with 1.2 GHz PC.

• Journal of Information Technology Applications and Management
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• v.21 no.4
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• pp.225-245
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• 2014

ICT based convergence application is one of the most prevalent industrial issue these days. Despite of criticalness and potential economic opportunities of the ICT based convergence, theoretical research to analyze the feasibility and estimate the economic impact of the application is rather limited. This paper is intended to fill this research gap. In this respect, we develop theoretical framework to quantitatively estimate the differential benefits of convergent applications, which necessarily include underling ICT technology's contribution attributes extractions, and resulting value increments engendered from user's process effectiveness when ICT based service application is adopted. The research model to assess the differential value of the ICT based service application is developed, grounded on theoretical framework of TPC (Technology-to-performance chain) and contingency fit theories. Scenario based survey method is adopted, and SmartPLS 2.0. is used for statistical analysis of the structural equation model using 312 questionnaire. Valid statistical results are presented to provide useful insight.

• Asia pacific journal of information systems
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• v.4 no.2
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• pp.131-164
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• 1994

A contingency model of outsourcing is developed from the information systems (IS) literature and strategic management literature in order to assess the following question: What factors influence change in the extent to which an organization outsources IS functions? Based on the literature, this study identifies four IS factors-gaps in information quality, IS support quality, IS staff quality, and IS cost effectiveness-and three organizational factors-the gap in financial performance, strategic orientation, and the role of information technology in an organization-that influence the change in degree of outsourcing. These factors are hypothesized to influence the change in the extent of an organization's outsourcing of IS functions. From a mail survey of 188 top IS executives in U.S. companies, the results of analysis of covariance and bivariate correlational and multivariate regression analyses provide the following major findings: (a) This study found support for the proposed research model. (b) The change in the degree of IS outsourcing is determined by gaps in information quality, IS support quality, IS cost effectiveness, and financial performance and by the role of IT among IS and organizational factors.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.403-418
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• 2012

In this paper, we attempted to theorize the synergy effect between the value creating attributes for digital convergence model in the service industry. Our investigation is based upon contingency fit theory to understand the strategic fit for the two inherent value attributes of fixed and mobile value, as well as resolving fundamental limitations of service processes. Empirical validation of the derived research model is analyzed using hierarchical regression method. The results indicate that the relative advantage of each value creating attributes are strongly associated with the characteristics of domain service industries, and compatibility is critical to user adoption of convergent service model. Moreover, the less significant statistical impact of the synergy between mobile and fixed value attributes and others implies that each value attribute uniquely contributes to particular IT convergence model, which thereby offers critical insight that focusing the convergent value in conjunction with specific application domain is the most appealing managerial focus. The findings provide useful insight for the further research in IT based industry convergent business model areas.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.1
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• pp.17-24
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• 2019

In this paper, we analyzed the effect of power system load model on the short-term voltage stability analysis results. First, we introduced common load models. We also confirmed that some load models can not represent actual system phenomena even if the model parameters are optimized. Also, we studied about the influences of load parameters and regional characteristics of load model on the sort-term voltage stability of KEPCO power system considering the contingency. The results showed that the importance of selecting a load model was confirmed again. And we recognized about it can be understood that it should reflect the load characteristics of the area near the assumed contingency more accurately.

• Journal of Electrical Engineering and Technology
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• v.12 no.6
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• pp.2196-2207
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• 2017

This paper presents a two-stage market auction model in a pool-based electricity market, which explicitly takes into account the system network security. The security network-constrained market auction model considers the use of corrective control to yield economically efficient actions in the post-contingency state, while ensuring a certain security level. Under this framework, the proposed model shows not only for quantifying the correlation between secure system operation and efficient market operation, but also for providing transparent information on the pricing system security for market participants. The two-stage market auction procedure is formulated using Benders decomposition (BD). In the first stage, the market participants bid in the market for maximizing their profit, and the independent system operator (ISO) clears the market based on social welfare maximization. System network constraints incorporating post-contingency control actions are described in the second stage of the market auction procedure. The market solutions, along with the BD, yield nodal spot prices (NSPs) and nodal congestion prices (NCPs) as byproducts of the proposed two-stage market auction model. Two benchmark systems are used to test and demonstrate the effectiveness of the proposed model.

• Communications for Statistical Applications and Methods
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• v.19 no.3
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• pp.495-500
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• 2012

We consider a Bayesian test of independence in a two-way contingency table that has some zero cells. To do this, we take a three-stage hierarchical Bayesian model under each hypothesis. For prior, we use Dirichlet density to model the marginal cell and each cell probabilities. Our method does not require complicated computation such as a Metropolis-Hastings algorithm to draw samples from each posterior density of parameters. We draw samples using a Gibbs sampler with a grid method. For complicated posterior formulas, we apply the Monte-Carlo integration and the sampling important resampling algorithm. We compare the values of the Bayes factor with the results of a chi-square test and the likelihood ratio test.

• Journal of Agricultural Extension & Community Development
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• v.8 no.2
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• pp.235-244
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• 2001

The objectives of this study were to inquire the theories associated with YLD (Youth Leadership Development), and to draw implications for improving youth leadership abilities, The results of the inquiry revealed the theories associated with YLD as follows; 1. All youth have leadership potential and abilities, but there were few programs to improve it. 2. Activity-Observation-Reflection model of Hughes, Ginnett & Curphy(1993) and Awareness-Interaction-Mastery model of Linden & Fertman(1998) were the best effective YLD models. 3. Situational contingency approach was very appropriate theory associated with YLD. 4. The learning of leadership skills had occurred within an educational context known as experiential learning, so it was the best method of YLD.

• Korea Journal of Hospital Management
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• v.13 no.2
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• pp.1-19
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• 2008

BSC(balanced scorecard) is expected of the effective integrated tool of the management problem such as links of the management vision, the strategy, and the business scheme. This study discusses the recent development and problems of hospital BSC practices in in several countries. First, the article discuss the recent development and problems of hospital BSC implementation. Second, we review the links of strategic alignment with hospital's strategy and BSC on weight design, organizational culture and hospital performance. Finally, we explore hospital BSC framework that clarified easy to understand integrative approach to hospital BSC research using contingency theory model.