• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.502-512
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• 2017

The presence of DGs in power system networks tends to negatively affect the protective relays coordination. The proposed method introduces an approach to minimize the numbers of relays that acquire new settings on contrary to their original settings (case without DG), to achieve relays coordination in case of adding DG, since relays coordination with minimum number of relays of re-adjusted settings represents economical target, especially in networks containing mixture of electromechanical and adaptive digital relays. The scheme decides the possible minimum number of re-adjusted relays and their locations in an optimum manner to achieve proper relays coordination in case of adding DGs. The proposed approach is divided into two successive phases; the first phase is stopped when the first relays coordination solution is achieved. The second phase increases the possibility to keep higher number of relays at their original settings than that obtained in first phase through achieving multi solutions of relays coordination. The proposed approach is implemented and effectively tested on the well-known IEEE-39 bus test system.

• 한국시스템다이내믹스연구
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• 제11권4호
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• pp.5-23
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• 2010

The competition between hospitals has become an issue for many hospitals because of the sudden increased number of health providers. As the marketing or customer management have become important factors as means of competition, a number of hospital have been considered or already adopted the coordination system. A system dynamics model is developed to see the effect of the hospital coordination system. This paper after briefly explaining the structure of the system dynamics model, discusses the roles of the hospital coordination system with examples. The system dynamics model quantifies through simulations the process of effects of coordination system on the number of customers, productivities of employees (nurses and doctors), and finally the financial status. As a conclusions of the simulations and their analysis, it is concluded that coordination system could be more effective than the investment to the facilities. Since the study is based on only one hospital case, it is limited. However, it explains the mechanism of the coordination system quantitatively as well as qualitatively.

• 대한화학회지
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• 제53권5호
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• pp.609-612
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• 2009

• Bulletin of the Korean Chemical Society
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• 제9권6호
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• pp.365-368
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• 1988

Coordination chemistry of organotin(IV) dithiocarbamate complexes has been examined in terms of far infrared and $^{119}Sn$-NMR spectroscopies. Although the Sn-S stretching vibrational bands of the complex could not be correlated with the bonding nature of the dithiocarbamate ligand, $^{119}Sn$ chemical shifts were sensitive enough to distinguish clearly the coordination number of tin, and as such the bonding mode of the dithiocarbamate ligand could be indentified to be monodentate or bidentate. Thus the $^{119}Sn$-NMR study on new cyclohexyltin(IV) dithiocarbamate complexes along with the known complexes suggests that the bonding mode of the dithiocarbamate ligands and the consequent coordination number of tin are determined mainly by the inductive effects of the organic groups attached to the tin atom.

• STI Policy Review
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• 제2권1호
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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.

• 대한전기학회논문지:전력기술부문A
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• 제48권9호
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• pp.1103-1111
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• 1999

STACOM will be utilized to control substation voltage in the near future. Although STACOM shows good voltage regulation performance owing to its rapid and continuous response, it needs additional reactive power compensation device to keep control margin for emergency such as fault. ULTC transformer is one of good candidates. This paper presents a Kohonen Neural Network (KNN) based coordination control scheme of ULTC transformer and STACOM. In this paper, the objective function of the coordination control is minimization of both STACOM output and the number of switchings of ULTC transformer while maintaining substation voltage magnitude to the predefined constant value. This coordination, control is performed based on reactive load trend of the substation and KNN which offers optimal tap position in view of STACOM output minimization. The input variables of KNN are active and reactive power of the substation, current tap position, and current STACOM output. The KNN is trained by effective Iterative Condensed Nearest Neighbor (ICNN) rule. This coordination control applied to IEEE 14 bus system and shows satisfactory results.

• 한국컴퓨터정보학회논문지
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• 제28권1호
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• pp.151-159
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• 2023

디지털 시대에 혁신은 정보기술발전의 핵심이다. 본문은 혁신 시스템 내 지역혁신능력의 차이를 새로운 관점에서 분석하고 있다. 본 연구는 커플링조정모델을 이용하여 중국의 31개 성, 시, 자치구의 혁신시스템(혁신투입, 혁신산출, 혁신환경)에 대해 커플링 정도를 비교 분석하고 있다. 분석 결과는 두 가지로 요약할 수 있다. 첫째, 중국의 전반적인 커플링 조정 수준은 낮다. 그리고 양호한 커플링과 높은 수준의 커플링 단계에 있는 지역의 수는 많지 않다. 둘째, 커플링의 전반적인 추세는 상승하고 있으나, 상대적으로 양호한 커플링 단계에 있는 지역은 대부분이 지역경제발전 수준이 높은 동부 연해안 지역에 분포되어 있다. 본문의 연구 결과는 혁신 능력 평가에 대한 새로운 관점을 제공할 수 있으며, ICT 산업의 발전을 촉진하는 데 혁신이 중요한 영향을 미칠 수 있음을 강조하고 있다.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.409-411
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• 2014

Based on the first-principles computations, the nature of the microscopic geometry of the molecule-electrode contacts was addressed. The single-molecule junction was prepared by connecting hexanediothiolate (HDT) to Au(111) electrodes via one, two, and three Au adatoms having coordination number of one (CN1), two (CN2), and, three (CN3), respectively. The contact atomic structure and energy of the stretched Au-HDT-Au junction was observed. The analysis revealed that the contact geometry with lowest coordination number (CN1) is energetically more stable than CN2 and CN3.

• Journal of Electrical Engineering and Technology
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• 제11권6호
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• pp.1590-1599
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• 2016

The installation of distributed generation (DG) in the electrical networks has numerous advantages. However, connecting and disconnecting of DGs (CADD) leads to some problems in coordination of protection devices due to the changes in the short circuit levels in the different points of network. In this paper, an adaptive method is proposed based on available setting groups (SG) of relays. Since the number of available SG is less than possible CADD states, a classifying index (CI) is defined to categorize the several states in restricted setting groups. Genetic algorithm (GA) with a suitable objective function (OF) is used as an optimization method for the classification. After grouping, a modified coordination method is applied to achieve optimal coordination for each group. The efficiency of the proposed technique is demonstrated by simulation results.

• 한국언어정보학회지:언어와정보
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• 제7권2호
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• pp.59-79
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• 2003

Coordination in natural language is often syntactically explained by the rule schema X \longrightarrow X′ and X", where X′ and X" refer to expressions of a like syntactic type. While this schema does explain a lot of instances of coordination, it is well known that this schema also gives rise to serious structural ambiguity, leading not only to numerous unintended interpretations but also to a high degree of unnecessary computational complexity. In order to identify intended interpretations, we need to take into account a number of clues at all the levels of morphology, syntax, semantics, and pragmatics/discourse. In this paper, we propose, with an accompanying data analysis, principles of symmetry and coherency for an effective and reasonable identification of intended interpretations from coordination-bearing sentences.