• Journal of Korean Society of Transportation
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• v.11 no.1
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• pp.87-103
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• 1993

The subject this paper is the signal control strategy under oversaturated conditions. The nature of traffic control for oversaturation is essentially different from the standard control modes. While under non-saturated situation traffic control is needed for the sake of safety and efficiency, the throughput is essential under oversaturated conditions. Therefore berth objective and strategies differ. For an oversaturated stream the cycle time and the signal offset are thought to be of rather secondary importance. For this case the green split may well be the most important control variable to serve the excessive demand. Up to now, however, most efforts have concentrated on the strategy with the concept which lies just on the extension of Webster's. "Green-split Coordination Strategy for Over-Saturated Networks", presents newly contrived three types of strategies named Forward-coordination, Backward-coordination and Network-coordination respectively and describes the algorithms with the evaluations. The forward coordination strategy treats the forward wave of flow between two signals. The aim is to prevent the outbreak of queue due to the accumulation of temporary excess of demand in near-saturation or saturation flow. The backward coordination strategy treats the backward rave of flow between two signals. The goal is to prevent the waste of green time caused by the exit block at the upstream signal. for this purpose a feedback regulation is provided of the upstream green-split so that the inflow-outflow balance is kept zero. The resultant surplus of green time is alloted to other signal stages. Also here the examination is made of the appropriate value of the feedback control parameter. The network coordination strategy is operated to maximize the network throughput in a specific direction applying a bang-bang control at the bottleneck intersection. This is a type of intervenient control for policy reasons. For this strategy the green-split coordinations, particuarly the backward coordination, are essential as the tactical elements. In order to evaluate the preposed strategies those are compared with the latest existing strategy called saturation-degree-ratio control by the simulation experiments in an assumed 4$\times$4 grid network. The results are satisfactory showing a 10-15% reduction in delays and a 15% increase in network capacity.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1781-1790
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• 2016

This study focuses on the coordination control problem of multiple electrical excited synchronous motor systems. A robust coordination controller is designed on the basis of cross coupling and an interval matrix. The proposed control strategy can deal with load uncertainty. In addition, the proposed control strategy is applied to a high-power metal-rolling system. Simulation and experiment results demonstrate that the proposed control strategy achieves good dynamic and static performance. It also shows better coordination performance than traditional proportional-integral controllers.

• Korean Institute of Interior Design Journal
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• v.20 no.1
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• pp.51-60
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• 2011

Analysis of trend by various information is systematically approached by strategy differentiating in Interior Design. At the present, trend is approached by intuitive viewpoint without systematic strategy and analysis system about interior coordination activity. And, it is not still established specific systematic architecture of the interior coordination by logical and academical approach. This Study set the goal at overall understanding about the Trend that shifting fast and offering objective data. Therefore, I approached the semiology-oriented process as the most suitable academical system on analysis of interior coordination trend. Object target of analysis was investigated to three domestic and overseas exhibitions announced from 2007 to 2008. These analysis was based on the context and text from the life style and the major determinant theme of the age of each exhibition. Also, it was arranged color, material and texture by the related expression system with topics and theme keywords. And it'll be considered as utilizing the code of specific application in interior coordination which is from the investigating about exhibition. Therefore, this study will be expected to help in meaning transmission and methodology establishment by more beneficial objective system, when designer work the interior coordination practically through the establishment of systematic viewpoint about interior coordination.

• Journal of Digital Convergence
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• v.11 no.3
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• pp.73-83
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• 2013

Effective policy coordination is necessary function for successful policy implementation. Korean government, for effective policy coordination, had developed the policy coordination system in the Prime Minister's Office. The Prime Minister's Office had successfully implemented policy coordination tasks during 35 years. The Prime Minister's Office had systemized policy coordination institutions and developed organizational capacity for effective coordination, and utilized various strategies, such as power, persuasion, and technical strategy. Based on the system, capacity, and various strategies, ]the Prime Minister's Office had achieved 90% of the asked policy conflict problems and completed 85% of coordination tasks within 6 months. The purpose of this study is for reviewing the performance of successful coordination of Prime Minister's Office and searching for some implications. For the study, the author analyzed the 429 policy conflict problems which had been recorded in 8 Policy Coordination White Papers.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.2
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• pp.279-284
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• 2011

Harmonic distortions in current waveform may cause significant problems in electric power system facility and operation. This paper presents an adaptive parameter estimation method to detect harmonic current components caused by nonlinear loads. In addition, a coordination strategy for multiple inverter-interfaced distributed generators to compensate the harmonic currents is discussed. The coordination strategy is realized by distributing the harmonic compensation participation index to individual distributed generators. The harmonic compensation participation index can be determined by the amount of remaining power generation capacity of each distributed generator. Simulation results based on switching-level inverter models show that the proposed harmonic detection method has good performance and the coordination strategy can improve harmonic problems efficiently.

• Korean Management Science Review
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• v.12 no.2
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• pp.1-14
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• 1995

Recently Korean textile industry has been in the phase that requires its strategy change from the less-develped country style of the labor-intensive products to the developed country style of the technology-intensive products. It needs to make more efforts to develop the value-added products to meet the customer's various needs. In addition, development of technology, equipment, and design is required to implement its corporate strategy successfully. Although Korean textile companies have currently kept skillful labor and advanced equipments, they are losing their share in the international textile markets. This is mainly because corporate management has not been involved with efficient strategy. Strategy is an adoption of a company to environment by its corporate members, thus leading to the requirement of coordination of the main functions such as manufacturing and marketing. In fact, the coordination of the two departments toward reaching the corporate goal is not easy since the two are interested in different areas, respectively. Manufacturing people show their interests in production capacity, equipment layout, process technology, quality, purchasing, and labor while marketing people, target customer, product mix, advertisement, product specification, and customer service. For this reason, conflicts sometimes happen between the two departments. There are, however, many area that need a horizontal cooperation, for instance, in layout, process technology, product mix, and potential demand. Therefore, reciprocal coordination is necessary for achieving the firm's common objectives. This study was concerned with determining the factors that enhance the competitiveness of textile firms so that they could reach the common goal of the two departments with a horizontal collaboration.

• 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.

• Korean Journal of Applied Biomechanics
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• v.24 no.3
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• pp.229-238
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• 2014

This study comparatively analyzed the speed and segment coordination characteristics of Taekwondo hand techniques, while different attention focusing strategies were utilized. Ten elite Taekwondo poomsae athletes participated, and three different strategies (no focus, target focus, body focus) were utilized in random order. The hand velocity and upper body segment coordination characteristics were analyzed, with the following results. First, the maximum magnitudes of the hand velocity differed between the focus conditions for the Araenaereomakgi and Momtongjireugi techniques. Second, the angular velocity and kinetic energy transfer patterns of the segments differed between the focus conditions, and in the case of the body focus condition, the movement was more correct according to the theory. Third, the shoulder and elbow joint coordination patterns differed between the focus conditions, with more efficient movement shown with the body focus condition. In conclusion, we confirmed the potential of effectively using an attention focusing strategy in a taekwondo teaching situation. However, the effect on the movement coordination and results of the movement could be changed by a difference in the cue provided or the type of the task. In addition, depending on the task, the attention focusing strategy could affect the efficiency of the movement. Therefore, coaches and masters of Taekwondo will have to constitute determine the appropriate attention focusing cues based on the task.

• Transactions on Electrical and Electronic Materials
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• v.18 no.3
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• pp.169-175
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• 2017

A safe and reliable protection system in distribution networks, specifically, those hosting distribution generation units, needs a robust over-current protection scheme. To avoid unintentional DG disconnection during fault conditions, a protection system should operate quickly and selectively. Therefore, to achieve this aim, satisfying coordination constraints are important for any protection scheme in distribution networks; these pose a challenging task in interconnected and large-scale networks. In this paper, a new coordination strategy, based on the same non-standard time-current curve for all relays, in order to find optimal coordination of directional over-current relays, is proposed. The main aim is to reduce violations, especially miscoordination between pair relays. Besides this, the overall time of operation of relays during primary and backup operations should be minimized concurrently. This work is being tackled based on genetic algorithms and motivated by the heuristic algorithm. For the numerical analysis, to show the superiority of this coordination strategy, the IEEE 30-bus test system, with a mesh structure and supplemented with distributed generation, is put under extensive simulations, and the obtained results are discussed in depth.

• STI Policy Review
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• v.2 no.1
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• pp.1-12
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• 2011

Korea is examining how to coordinate its S&T policies and solidify its position as a leader of infrastructure innovation policy that forms the foundation for many different policies. A number of questions have been raised, such as whether to install a superior coordinating body like the National Science and Technology Council (NSTC) or separate the budget allocation and coordination authority from the budget-planning ministry. Korea has tried using various institutional coordination devices and functions such as reorganizing its administrative ministries based on related functions and installing or reinforcing a superior coordinating body. In line with these discussions, the strengthening of the S&T policy coordination function through the NSTC is currently under review. In order to design an effective S&T coordination system in step with changing political and social demands, it is important to have a clear recognition of the current context as well as the unique institutional characteristics of Korea. This study examines the evolution of Korea's S&T policy coordination systems and analyzes its features.