• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.9
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• pp.1521-1526
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• 2007

This paper presents the application of Adaptive Evolutionary Algorithm (AEA) to search an optimal setting of overcurrent relay coordination to protect ring distribution systems. The AEA takes the merits of both a genetic algorithm (GA) and an evolution strategy (ES) in an adaptive manner to use the global search capability of GA and the local search capability of ES. The overcurrent relay settings and coordination requirements are formulated into a set of constraint equations and an objective function is developed to manage the overcurrent relay settings by the Time Coordination Method. The domain of overcurrent relays coordination for the ring-fed distribution systems is a non-linear system with a lot of local optimum points and a highly constrained optimization problem. Thus conventional methods fail in searching for the global optimum. AEA is employed to search for the optimum relay settings with maximum satisfaction of coordination constraints. The simulation results show that the proposed method can optimize the overcurrent relay settings, reduce relay mis-coordinated operations, and find better optimal overcurrent relay settings than the present available methods.

• Knowledge Management Research
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• v.10 no.4
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• pp.93-114
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• 2009

This paper presents a knowledge-based view of the multi-business firm. The multi-business firm has advantages in technological innovation and knowledge creation to the extent that it embodies various ideas and resources, and recombines them more effectively and efficiently than market contracts. The purpose of this paper is to identify how to organize the multidivisional form (M-form) structure to realize such advantages. We first differentiate within-division innovation and cross-division innovation, and explain why cross-division innovation, despite its higher performance potential, would be more difficult to achieve, compared to within-division innovation. Then, we offer the propositions about how to promote cross-division innovation with references to resource capability and coordination capability that is, in turn, composed of structural and control system, social capital, and human resource management system. We conclude by discussing theoretical and practical implications.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2668-2671
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• 2010

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.345-346
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• 2015

In this paper, we study the generator capability curve about the relay coordination on the basis of generator protection and control developed by NERC.

• Industrial Engineering and Management Systems
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• v.12 no.3
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• pp.224-233
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• 2013

In supply chain management, the supply contract can induce collaboration and coordination among the supply chain members in order to optimize supply chain performance. Numerous supply contracts have been examined; however, some difficulties related to the application of these contracts still occur. One of the solutions is to apply the composite supply contract which can assist in the supply chain coordination. This research examines the composite contract of the revenue sharing and quantity flexibility contracts in a two-stage supply chain, which comprises a retailer and a supplier. In this research, a mathematical model of the composite contract is developed; then, the applicability of the proposed composite contract is examined by investigating its capability in terms of supply chain coordination and profit allocation. In the numerical experiments, the composite revenue sharing-quantity flexibility contract showed that it is superior to both component contracts in terms of supply chain coordination and profit allocation among supply chain members.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1556-1570
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• 2016

In the process of virtual inertia control (VIC), the frequency regulation capability of the directly-driven wind turbine with permanent-magnet synchronous generator (D-PMSG) on wind farm is related to its rotor kinetic energy and capacity margin. This paper proposes the method for assessing the D-PMSG frequency regulation capability and defining its coefficient according to the operating state of wind power generators. In addition, the calculating method of parameters in VIC is also discussed according to the principles of primary frequency regulation and inertia response of synchronous generators. Then, by introducing the capability coefficient into the proportion-differential virtual inertia control (PD-VIC) for power coordination, a coordinated virtual inertia control (C-VIC) strategy is developed, with the consideration of the difference in frequency regulation capability between wind power generators. The proposed control method can not only give full play to the frequency regulation capability of wind power generators, decrease the movements of the pitch angle control system but also bring some self-coordination capability to different wind power generators thus to avoid a secondary drop in system frequency. The simulations and experiments prove the proposed method to be effective and practicable.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.125-128
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• 1990

A program for the protection coordination of distribution systems is reported. The developed program nailed DISCO, consisting of two modules has a capability of selling the overcurrent relays, reclosers, sectionalizers, fuses which are commonly used in the primary feeder systems. Setting is performed in a downstream fashion starting from the substation, and coordination rules are applied identifying the pattern of the primary-backup devices based on the depth-first search. T/C curves of various devices are handled by digitization for accuracy and various graphics and windows are adopted for user-friendly interface.

• Journal of the Korea Society of Computer and Information
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• v.28 no.1
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• pp.151-159
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• 2023

In the digital age, innovation is at the heart of information technology development. This paper explores the differences of regional innovation capabilities from within the innovation system from a new perspective. By applying the coupling coordination degree model, the coupling coordination degree analysis is conducted for the three systems of innovation (innovation input, innovation output, and innovation environment) in 31 provinces, municipalities, and autonomous regions of China. The results show that: the overall level of coupling coordination degree in China is low, and the number of provinces in good coordination and quality coordination is low number, but they are all distributed in the eastern economically developed regions, showing a high correlation between regional innovation and regional economic development. The overall trend of China's innovation coordination is on the rise. The research results of this paper can provide a new perspective for the evaluation of innovation capability, and also provide an important impact of innovation on promoting the development of ICT industry.

• Journal of the Ergonomics Society of Korea
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• v.30 no.2
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• pp.365-373
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• 2011

The existing GOMS model overestimates the performance time of mouse activities because it describes them in a serial sequence. However, parallel movements of eye and hand(eye-hand coordination) have been dominant in mouse activities and this eye-hand coordination is the main factor for the overestimation of performance time. In this study, therefore, the revised CGOMSL model was developed to implement eye-hand coordination to the mouse activity to overcome one of the limitations of GOMS model, the lack of capability for parallel processing. The suggested revised CGOMSL model for drag activity, as an example for one of mouse activities in this study, begins visual search processing before a hand movement but ends the visual search processing with the hand movement in the same time. The results show that the revised CGOMSL model made the prediction of human performance more accurately than the existing GOMS model. In other words, one of the limitations of GOMS model, the incapability of parallel processing, could be overcome with the revised CGOMSL model so that the performance time should be more accurately predicted.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.9
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• pp.1822-1830
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• 2002

The paper describes the development of a decomposition based multidisciplinary design optimization (MDO) method that coordinates each of disciplinary subspace optimization (DSO). A multidisciplinary design system considered in the present study is decomposed into a number of subspaces based on their own design objective and constraints associated with engineering discipline. The coupled relations among subspaces are identified by interdisciplinary design variables. Each of subsystem level optimization, that is DSO would be performed in parallel, and the system level coordination is determined by the first order optimal sensitivities of subspace objective functions with respect to interdisciplinary design variables. The central of the present work resides on the formulation of system level coordination strategy and its capability in decomposition based MDO. A fluid-structure coupled design problem is explored as a test-bed to support the proposed MDO method.