• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.3
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• pp.427-438
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• 2012

The SCADA(Supervisory Control and Data Acquisition) systems are used to control some critical national infrastructures such as electricity, gas, and water distribution systems. Recently, there are many researches on key management scheme for secure communication due to change to the open network environment. We propose a new key management method which is established on ID-based cryptosystem using pairing on MTU(Master Terminal Unit), Sub-MTU, and RTU(Remote Terminal Unit). Furthermore, we present a redistribution protocol of private key of each device and a system recovery protocol as a countermeasure of exposure of KMS(Key Management System) master key which is occurred by some unexpected accidents or malicious attacks.

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.293-294
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• 2007

• The Journal of Asian Finance, Economics and Business
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• v.6 no.2
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• pp.203-212
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• 2019

A system Integrator (SI) makes a consortium with multiple providers of hardware and software solutions to sell an information system. The success of information systems (IS) mainly depends on establishing a trustful relationship between SI supplier and client, and delivering high-quality system. However, the determinants of trust and system quality have been investigated mostly from the perspective of s ystem buyers rather than system sellers. This study examines the influence of key variables that SI can handle to improve trust and system quality which finally leads to user satisfaction toward SI. This study adopts resource complementarity, user participation and information sharing as the key variable then builds a research model to explain their relationships to user satisfaction. Respondents are recruited from 251 firms that have built any information system in recent two years in South Korea. Results of partial least square (PLS) modeling analysis show that both resource complementarity and information sharing have positive relationships with trust. Also the relationships between trust, system quality and user satisfaction toward S.I are supported. In addition, the mediating roles of trust and system quality are identified. We discussed some of the key managerial and theoretical implications of the paper and suggested further research directions.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.329-334
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• 2012

The distribution submarine cables are normally used for power supply at island, which are mostly installed in the southern coast of KOREA, and partially installed in the west coast and Jeju-Island. There are two way of submarine cable burying system, buried and unburied type. Since 2003, KEPCO is entirely being constructing the distribution submarine cable by buried type. In this case, 'burial depth' is key index for evaluating the suitability of the buried situation. Therefore, the measurement accuracy of 'burial depth' is a big issue for burying system in the distribution submarine cable. This paper demonstrates the measurement error of burial depth that is affected by electrical factor such as grounding type of submarine cable in case of magnetic field detection method, and indicates the method to reduce the measurement error in buried type of distribution submarine cable system.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.173-180
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• 2008

In this paper, we proposed an algorithm for an effective public key and private key generation to implement a secure asymmetric watermarking system against the public key attack. The public key and private key generation is based on the linear transformation using a special matrix and the keys are designed to be able to have high correlation value. We also proposed a counter plan of public key attack. This method uses a multiple public key generation and distribution. As the results, the correlation value between the public key and the private key is high in the watermarked image. After the public key attack. this can detect the correlation by using other public key.

• Interaction and multiscale mechanics
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• v.1 no.3
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• pp.369-379
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• 2008

A combined stochastic diffusion and mean-field model is developed for a systematic study of the grain growth in a pure single-phase polycrystalline material. A corresponding Fokker-Planck continuity equation is formulated, and the interplay/competition of stochastic and curvature-driven mechanisms is investigated. Finite difference results show that the stochastic diffusion coefficient has a strong effect on the growth of small grains in the early stage in both two-dimensional columnar and three-dimensional grain systems, and the corresponding growth exponents are ~0.33 and ~0.25, respectively. With the increase in grain size, the deterministic curvature-driven mechanism becomes dominant and the growth exponent is close to 0.5. The transition ranges between these two mechanisms are about 2-26 and 2-15 nm with boundary energy of 0.01-1 J $m^{-2}$ in two- and three-dimensional systems, respectively. The grain size distribution of a three-dimensional system changes dramatically with increasing time, while it changes a little in a two-dimensional system. The grain size distribution from the combined model is consistent with experimental data available.

• The Journal of Industrial Distribution & Business
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• v.13 no.3
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• pp.1-12
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• 2022

Purpose: The revenue sharing contract has been widely used in industries, and its ability to coordinate the supply chain system has been studied by numerous researchers. By reviewing the representative studies on the revenue sharing contract, this study intends to analyze the key features of this coordinating contract and identify its potential to be a more advanced coordination program than the original contract. Research design, data, and methodology: This study reviews past studies on the revenue sharing contract. The selected studies are investigated with a focus on how this contract is described to realize the supply chain coordination and the key issues that they address. Results: The literature review reveals that the revenue sharing contract requires standardized details about what and how to share. This study also finds additional issues that need to be addressed by researchers to improve this coordinating contract. Conclusions: Future researchers are advised to unify the detailed contents of the revenue sharing contract to confirm that it successfully coordinates the supply chain system. In addition, this study proposes key research issues that would enhance the role of revenue sharing contract as a supply chain coordination program.

• Journal of the Korea Society of Computer and Information
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• v.21 no.3
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• pp.17-23
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• 2016

In this paper, we propose a model of the collaborative authoring tool and its implementation results. In the 'collaborative authoring and automatic distribution system,' users can create eBooks by using partial works (primary and edited sources) on the basis of copyright information registered by the primary author. The Collaborative Authoring Tool is a part of "the collaborative authoring and automatic distribution system" developed through research on "the development of key technologies of social work protection and content mashup tools" as an R&D project granted by the Korea Copyright Commission from 2013. In the collaborative authoring and automatic distribution system, authors of primary sources such as images, audio clips and video clips for eBooks can register them together with the copyright information; users can edit the primary sources to produce secondary sources and in turn register the secondary sources on the system; and users can create and distribute eBooks by using the sources registered in the system.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.555-557
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• 1997

This paper discusses a set of critical requirements in building and using a shared, integrated information management system for power distribution management and control. It then proposes a modem, object-oriented information system model for building such a system based on the current state of arts in database, GIS, and WWW technologies. The key of the proposal is that the shared database system should be the basis of integration efforts in power distribution management and control. A small-scale prototype is being developed to demonstrate the effectiveness of the proposed model.

• Journal of Power Electronics
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• v.17 no.5
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• pp.1317-1326
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• 2017

The cascaded H-bridge (CHB) multilevel converter is a promising topology for large-scale photovoltaic (PV) systems. The output voltage over-modulation derived by the inter-module active power imbalance is one of the key issues for CHB PV systems. This paper proposed a dynamic power distribution strategy to eliminate the over-modulation in a CHB PV system by suitably redistributing the reactive power among the inverter modules of the CHB PV system. The proposed strategy can effectively extend the operating region of the CHB PV system with a simple control algorithm and easy implementation. Simulation and experimental results carried out on a seven-level CHB grid-connected PV system are shown to validate the proposed strategy.