• Asia pacific journal of information systems
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• v.17 no.4
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• pp.133-163
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• 2007

Growth in the outsourcing market signals that firms of all sizes believe outsourcing will ultimately deliver many benefits and conveniences. But there are not many firms satisfied with the results of outsourcing. What is more, previous researches were fragmentary analyses focused on specific variables of outsourcing such as sourcing decisions, partnership rather than comprehensive analysis. Thus, they could not propose general systematic methodologies applicable to the real situation. To solve these problems, we developed an integrated theoretical framework that considered both contract with the hard side and trust with the soft side from a contingency viewpoint and tested this model using 143 data of Korean companies executing outsourcing. In addition, we examined how situational factors(outsourcing task complexity and outsourcing management competence) affects each path in the research model. The results of this study are as follows. First, it was proved the theory that trust is not a substitute for contract but its complement. Previous empirical studies on outsourcing success factors were focused on the establishment of successful partnership on the assumption that trust can replace contract in many situations. According to the results of our empirical analysis, however, contract and trust were in a mutually complementary relation with each other and their emphasis was different. Furthermore, different from previous researches, it was found effective to use trust as a supplementary tool and contract as a main means in outsourcing management strategy. Second, this study provided an integrated view that sees both contract and trust from a contingency viewpoint in theoretically reestablishing the relationship between contract and trust. Previous researches leaned to specific variables or theory-centered fragmentary analysis, but this study proposed a more practical and integrated research model and tested its effectiveness. Based on the results, with the model, decision makers are expected to scrutinize outsourcing situation more closely and to have a practical insight to the situation. Third, it was found that contract mechanism and trust building do not have a direct effect on outsourcing performance but relationship management intensity mediates the effect of contract mechanism and trust building. This is considered significantly meaningful to outsourcing partners who have believed that outsourcing would be successful if a contract is made properly or trust is built. Lastly, the path from trust building to relationship management intensity was moderated by informed buying, as the path coefficients from trust building to relationship management intensity varied by the degree of informed buying competence.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.453-463
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• 2013

The probabilistic nature of renewable energy, especially wind energy, increases the needs for new forms of planning and operating with electrical power. This paper presents a novel approach for determining the short-term generation schedule for optimal operations of wind energy-integrated power systems. The proposed probabilistic security-constrained optimal power flow (P-SCOPF) considers dispatch, network, and security constraints in pre- and post-contingency states. The method considers two sources of uncertainty: power demand and wind speed. The power demand is assumed to follow a normal distribution, while the correlated wind speed is modeled by the Weibull distribution. A Monte Carlo simulation is used to choose input variables of power demand and wind speed from their probability distribution functions. Then, P-SCOPF can be applied to the input variables. This approach was tested on a modified IEEE 30-bus system with two wind farms. The results show that the proposed approach provides information on power system economics, security, and environmental parameters to enable better decision-making by system operators.

• Journal of the Korean Data and Information Science Society
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• v.10 no.2
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• pp.457-464
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• 1999

In this paper, we propose an overlapped mosaic plot which proposed by Hartigan and Kleiner(1981) represents the counts in $2{\times}2$ contingency table directly by tiles whose area is proportional to the cell frequency. Overlapped mosaic plot provides some measurements of association including dynamic graphics for mosaic plots. Dynamic graphics for mosaic plots give some useful informations when one gets some measurements of association and selects a model, and current statistical software does not provide this feature. We can see the deviations between observation and estimate of independence from overlapped mosaic plot. This dynamic graphics give some useful informations how far this data are apart from independence.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.5
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• pp.239-256
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• 2009

The major issues of managing an organization and its environments are on how to establish a community for their co-survival and collaboration. This study is on the principles and management practices for establishing the community of organization and its environments based on the power circulatory approach, so that it contributes to creation of the social orders for co-survival and collaboration. In order to do this I discussed the theories and practices of the power circulatory approach, and then suggest their application to establishment of the co-survival community for organization and its environment. According to results the power circulatory approach offers theoretical and managerial tools which establish the co-survival community for organization and its environments, so that it increases likelihood of their co-survival and collaboration. Furthermore I discussed the position of the power circulatory approach to co-survival and collaboration in a manner that displays similarities and differences with exiting approaches such as the contingency and population ecology model.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.411-420
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• 2013

Recently, Korean system operating conditions have gradually approached an upper limit. When a contingency occurs, the power system may have no solutions. Different from the cases of bad initial guesses or the solutions are too close to the solvability boundary in which numerical methods can be applied, for unsolvable cases, the only way to restore solvability would be structure modifications. In this paper, a new approach for corrective and preventive control to such cases is proposed in two steps: (i) finding any solution regardless its feasibility; (ii) for the infeasible solution, make it feasible with additional modifications at load buses having Distributed Energy Resources. The test case built based on the peak load profile of 2008 by KEPCO including 1336 buses is analyzed. Since reactive power compensation is optimized to restore solvability, all demands are met, therefore no blackouts happen. The proposed method was integrated in the LP program designed by power21 Corporation.

• Proceedings of the Korean Statistical Society Conference
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• 2005.11a
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• pp.31-36
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• 2005

An identification and characterization of susceptibility genes for common complex multifactorial diseases is a challengeable task, in which the effect of single genetic variation will be likely dependent on other genetic variations(gene-gene interaction) and environmental factors (gene-environment interaction). To address is issue, the multifactor dimensionality reduction (MDR) has been proposed and implemented by Ritchie et al. (2001), Moore et al. (2002), Hahn et al.(2003) and Ritchie et al. (2003). With MDR, multilocus genotypes effectively reduce the dimension of genotype predictors from n to one, which improves the identification of polymorphism combinations associated with disease risk. However, MDR cannot handle missing observations appropriately, in which missing observation is treated as an additional genotype category. This approach may suffer from a sparseness problem since when high-order interactions are considered, an additional missing category would make the contingency table cells more sparse. We propose a new MDR approach with minimum loss of sample sizes by considering missing data over all possible multifactor classes. We evaluate the proposed MDR by using the prediction errors and cross validation consistency.

• Journal of Fashion Business
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• v.6 no.5
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• pp.41-47
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• 2002

Until now, there is a tendency of most textile research focused on the certain specific area of textiles in profound. This paper based on the case study of inspection of manufacturing men's formal wear has been investigated in the relationship between defection of men's formal wear and mechanical properties of textile for fall and winter. As a results of implementing Pearson's Correlation, density, blend rate, bending property, the rate of silk blend, the formality of sewing are correlated with defection of men's formal wear. However, it is required the defection of classification standard in various types of the finished product in a further study. In addition to increase efficiency of production in the manufacture, it is necessary for scholars to investigate the direction of research according to the contingency approach based on the systems approach.

• KIEE International Transactions on Power Engineering
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• v.5A no.3
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• pp.303-308
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• 2005

The restructure of the electrical power industry is accompanied by the extension of the electrical power exchange. One of the key pieces of information used to determine how much power can be transferred through the network is known as available transfer capability (ATC). The traditional ATC deterministic approach is based on the severest case and it involves a complex procedure. Therefore, a novel approach for A TC calculation is proposed using cost optimization in this paper. The Jeju Island interconnected HVDC system has inland KEPCO (Korean Electric Power Corporation) systems, and its demand is increasing at the rate of about $\10[%]$ annually. To supply this increasing demand, the capability of the HVDC system must be enlarged. This paper proposes the optimal transfer capability of the HVDC system between Haenam in the inland and Jeju in Cheju Island through cost optimization. The cost optimization is based on generating cost in Jeju Island, transfer cost through Jeju-Haenam HVDC system and outage cost with one depth (N-1 contingency).

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.3
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• pp.120-130
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• 2001

We present an approach to parallelizing optimal power flow that is suitable for distributed implementation and is applicable to very large interconnected power systems. This approach can be used by utilities to optimize economy interchange without disclosing details of their operating costs to competitors. Recently, it is becoming necessary to incorporate contingency constraints into the formulation, and more rapid updates of telemetered data and faster solution time are becoming important to better track changes in the system. This concern led to a research to develop an efficient algorithm for a distributed optimal power flow based on the Auxiliary Problem Principle and to study the convergence rate improvement of the distributed algorithm. The objective of this paper is to find a set of control parameters with which the Auxiliary Problem Principle (Algorithm - APP) can be best implemented in solving optimal power flow problems. We employed several IEEE Reliability Test Systems, and Korea Power System to demonstrate the alternative parameter sets.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.353-363
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• 2019

This paper presents a comprehensive simulation and assessment of gas dispersion above sea from a subsea release using a Computational Fluid Dynamics (CFD) approach. A 3D CFD model is established to evaluate the behavior of flammable gas above sea, and a jack-up drilling platform is included to illustrate the effect of flammable gas cloud on surface vessels. The simulations include a matrix of scenarios for different surface release rates, distances between surface gas pool and offshore platform, and wind speeds. Based on the established model, the development process of flammable gas cloud above sea is predicted, and the dangerous area generated on offshore platform is assessed. Additionally, the effect of some critical factors on flammable gas dispersion behavior is analyzed. The simulations produce some useful outputs including the detailed parameters of flammable gas cloud and the dangerous area on offshore platform, which are expected to give an educational reference for conducting a prior risk assessment and contingency planning.