• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.5
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• pp.494-501
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• 1999

In this research, ANN modeling method of SMES unit is developed for stability analysis, and the optimal site is selected to maximize stabilization effect of SMES unit. The ANN is trained by learning data which is obtained through the application of complex test function into the traditional mathematical mode. In order to verify the validity of proposed modeling method, fault data of sample power system is applied to both the traditional and the ANN models. When the response of traditional and proposed models are compared, the average error for the active and reactive power are 2.51[%], and 0.24[%], respectively. From the comparison, the relevance of proposed method is validated. For the transient stability analysis, an application method of the proposed model is presented, and the transient stability performance index, which describes system stabilization effect of SMES at disturbance, is also suggested, and optimal site selection method of SMES is presented. In the viewpoint of the voltage stability, system stabilization criterion of local bus is presented from P­V curve, and then optimal site which can maximize the voltage stabilization of the whole power system, is decided from the proposed voltage stability performance index.

• Asia-Pacific Journal of Business
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• v.13 no.2
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• pp.79-94
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• 2022

Purpose - The purpose of this study is to examine firm-level attributes related to Korean manufacturing small and medium-sized enterprises' (SMEs') decisions to implement smart factories. Design/methodology/approach - This study uses the provided by the Ministry of SMEs and Startups of Korea and the Korea Federation of SMEs. Manufacturing SMEs' decisions to implement smart factories in 2018-2019 were analyzed using multinomial logit and ordered logit models. Findings - The findings of this study suggest that firms' decisions to implement smart factories were positively related to firm size, R&D intensity, international market scope, and transactional relationships with customers. However, smart factory implementation decisions were not related to firm age and CEO gender. Research implications or Originality - This study illuminates firm-level attributes that may drive organizational innovation in the era of Industry 4.0 and thus contributes to the innovation adoption literature. This study also contributes to growing research on smart factories by analyzing the actual, progressive decisions to implement smart factories, as opposed to perceived intentions to implement them.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.2
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• pp.77-84
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• 2014

The purpose of this research is to identify and develop technology protection plans for small and medium-sized enterprises (SMEs) by analyzing past technology leakage patterns which were experienced by SMEs. We identified factors which affect the technology leakage, and analyzed patterns of the influences using a data mining algorithms. A decision tree analysis showed several significant factors which lead to technology leakage, so we conclude that preemptive actions must be put in place for prevention. We expect that this research will contribute to determining the priority of activities necessary to prevent technology leakage accidents in Korean SMEs. We expect that this research will help SMEs to determine the priority of preemptive actions necessary to prevent technology leakage accidents within their respective companies.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.1959-1963
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• 2007

SMES systems need cryogenic cooling systems. Conduction cooling system has more effective, compact structure than cryogen. In general, 2 stage GM cryocoolers are used for conduction cooling of HTS SMES system. 1st stages of cryocoolers are used for the cooling of current leads and radiation shields, and 2nd stages of cryocoolers for HTS coil. For the effective conduction cooling of the HTS SMES system, the temperature difference between the cryocooler and HTS coil should be minimized. In this paper, a cryogenic conduction cooling system for HTS SMES is analyzed to evaluate the performance of the cooling system. The analysis is carried out for the steady state with the heat generation of the HTS coil and effects of the thermal contact resistance. The results show the effects of the heat generation and thermal contact resistance on the temperature distribution.

• Journal of Electrical Engineering and Technology
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• v.3 no.1
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• pp.1-7
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• 2008

Superconducting Magnetic Energy Storage (SMES) can inject or absorb real and reactive power to or from a power system at a very fast rate on a repetitive basis. These characteristics make the application of SMES ideal for transmission grid control and stability enhancement. The purpose of this paper is to introduce the SMES model and scheme to control the active and reactive power through the power electronic device. Furthermore, an optimal priority scheme is proposed for the combination of active and reactive power control to be able to stabilize power transient swings.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.4
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• pp.328-332
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• 2007

A superconducting magnetic energy storage (SMES) system has shorter response time and longer life time, and is more economical, and environment-friendly than other uninterruptible power supply (UPS). A conduction cooling system is well answer for the high temperature superconductor (HTS) SMES system. Because the conduction cooling system is simple, light and small structure. The purpose of this paper is to design and verify the effective conduction cooling system for the HTS SMES system. The analysis of heat loads in cryostat is performed. Thermal shield heat loads, temperatures of HTS coil surface and conduction Cu plate are estimated and measured.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.794-796
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• 1997

The superconducting magnetic energy storage (SMES) system is considered to be useful to charge or release an energy in power system because of the high efficiency and quick response. But we need much capital to construct and to operate a SMES. A site and capacity of SMES are important elements for effective operating and planning. In this paper, we proposed a performance function to determine an optimal site and capacity of SMES according to variety condition of power system such as fault point. In addition, to demonstrate the validity of a proposed method, the simulations were carried out on two-machine 5-bus system.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1153-1155
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• 1998

Super-conducting Magnetic Energy Storage(SMES) system is considered to be useful unit to power system stabilizer because of high efficiency and quick response. For effective operating of SMES, we need much studies on accurate modeling and interface characteristics of SMES. In this paper, we propose useful method to SMES, modeling using Artificial Neural Network. Interface technique of proposed model and criterion of stabilization effect is presented. In addition, to demonstrate the validity of proposed method. the simulations were carried out on 3-machine 9-bus system.

• 한국벤처창업학회:학술대회논문집
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• 2022.04a
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• pp.129-134
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• 2022

This research investigates the effect of SMEs' digital transformation (DX) efforts in O2O platforms on customer engagement. Among the three DX stages (i.e., digitization, digitalization, and DX), this study focuses on digitalization, a practically viable DX phase for SMEs using O2O platforms. This study categorizes the DX efforts of SMEs into three: information diversity, responsiveness to customers, and the degree of functional use. To analyze the impact of these efforts on customer engagement, we conduct the zero-inflated negative binomial regression using the dataset of Naver Smartplace, one of the representative O2O platforms in South Korea. The analysis result confirms that all three factors have positive impacts on customer engagement. Therefore, this study demonstrates that employing O2O platforms can be an effective strategy for SMEs lacking resources to achieve successful DX.

• Journal of Korea Trade
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• v.26 no.2
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• pp.84-99
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• 2022

Purpose - This study carried out an empirical study of the impact of sustainability - which has been gaining attention as challenges are arising in supply chains based on existing trade networks due to the impact of the COVID-19 pandemic - on SCM performance and financial performance of Korean SMEs. The study seeks to propose a measurement model to enhance the SCM performance and financial performance of Korean SMEs and to identify the relationship between sustainability, SCM performance and financial performance to suggest implications to SMEs, governments, and relevant organizations. Design/methodology - Our Analysis established hypotheses that economic sustainability, environmental sustainability, and other factors related to sustainability have a positive impact on SCM performance and financial performance as well as SCM performance has a positive impact on financial performance, making empirical validations by utilizing Structural Equation Modeling based on data collected through survey from Korean SMEs. Findings - According to an empirical study, although environmental sustainability and economic sustainability among factors of sustainability had a positive influence on SCM performance, social sustainability did not have a statistically significant influence. Furthermore, it was learned that only economic sustainability had a positive influence on financial performance while SCM performance has a positive influence on financial performance. Originality/value - This empirical study explored the relationship between SCM performance and financial performance of Korean SMEs with a high tendency to depend on specific supply chains when the international trade network is in confusion and/or the global supply chain has collapsed. If Korean SMEs allocate management resources to the factors deducted from this study, they would be able to build more efficient supply chains and improve financial performance to improve sustainability.