• Journal of Power Electronics
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• v.18 no.1
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• pp.251-265
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• 2018

To enable a master-slave control independent microgrid system (MSCIMGS) to supply electricity continuously, the microgrid inverter should perform mode transfer between grid-connected and islanding operations. Transient oscillations should be reduced during transfer to effectively conduct a seamless mode transfer. This study uses a typical MSCIMGS as an example and improves the mode transfer strategy in three aspects: (1) adopts a status-tracking algorithm to improve the switching strategy of the outer loop, (2) uses the voltage magnitude and phase pre-synchronization algorithm to reduce transient shock at the time of grid connection, and (3) applies the hybrid-sensitivity $H_{\infty}$ robust controller instead of the current inner loop to improve the robustness of the controller. Simulations and experiments show that the proposed strategy is more practical than the traditional proportional-derivative control mode transfer and effective in reducing voltage and current oscillations during the transfer period.

• Journal of The Korean Association of Information Education
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• v.13 no.2
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• pp.127-134
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• 2009

As wireless-internet and mobile computer revitalizes, various teaching and learning strategies are appearing. In this study, we suggest a new integrated teaching method in u-learning environment effectively. First of all, to apply information technique to education effectively, we grasped various educational factors centered on learners. And then, we categorized them into contents, time and space as three vital factors and analyzed. Next, by combining the important factors, we suggested the new integrated teaching and learning strategy. We also operated personalized the integrated teaching for elementary school students and verified the effect. As a result, we learned that the integrated teaching was effective in the area of higher-level thinking presented as an effectiveness index, learning motivation and self-directed learning. That is, this study will promote excellence in education centered on learners in the hereafter u-learning environment and support general integrated education effectively.

• International Journal of Advanced Culture Technology
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• v.9 no.3
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• pp.8-15
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• 2021

This study was conducted with the purpose of exploring the dilemma and improvement strategies for the integrated management of extracurricular education programs at Duksung Women's University. The research method was finally composed of a procedure with a meeting of experts based on the procedure of collecting and analyzing the previous research literature. As for the contents of the study, the dilemma of the integrated management of the extracurricular education program at Duksung Women's University was presented first. Examples of dilemmas include difficulties in organizing and operating programs from the perspective of a roadmap customized for each grade level, difficulties in establishing a foundation for balanced mapping of core competencies and cultivating programs, difficulties in managing the performance of regular program monitoring and feedback improvement, and activating the linkage system between subjects and extracurricular education programs difficulties and difficulties in establishing a support system for the operation of the extracurricular education integrated management system were reflected. In addition, a strategy to complement and improve this dilemma was presented in a linkage. As a result of the study, the integrated management dilemma of Duksung Women's University's extracurricular education programs needs to be resolved in the long term through formal infrastructure such as external expert advice and expert exchange, and the development and use of related manuals should be considered aspects were analyzed. In addition, the content of this study was analyzed not only in the educational case of Duksung Women's University, but also in that it deals with cases that can be usefully referenced in most universities that develop and operate extracurricular education programs. Finally, this study presents an evidence-based practices that can be referenced in promoting the integrated management of extracurricular education programs in university sites, and the position and identity of extracurricular education throughout the university curriculum. It is judged that the significance and expected effect of the study can be obtained in that it provides an opportunity to improve from the management point of view.

• KCID journal
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• v.11 no.1
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• pp.64-76
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• 2004

For effective development of upland areas, e development model of upland area integrated improvement project are suggested which on standard type and integrated infrastructure improvement type, rural Income raising type and eco-friendly consolidation type

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.196-200
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• 2003

To fulfill the railroad station's duties efficiently, it is essential to view passenger transfer system within the railroad station and in the vicinity of railroad station in the context of broader technological developments in easy access to railroad station. To do the direct service to local station or easy transfer to other mass transportation modes, necessary courses for local govemments and each transportation agency involvement should be taken and long-term integrated transfer strategy must be found. The research designed here was designed to derive a general overview of the integrated transfer patterns with an emphasis on passenger intermodal transportation system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1999.04a
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• pp.174-174
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• 1999

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.3
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• pp.993-1014
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• 2021

This paper proposes a new image retrieval method called the 3D integrated multi-index to fuse SIFT (Scale Invariant Feature Transform) visual words with other features at the indexing level. The advantage of the 3D integrated multi-index is that it can produce finer subdivisions in the search space. Compared with the inverted indices of medium-sized codebook, the proposed method increases time slightly in preprocessing and querying. Particularly, the SIFT, contour and colour features are fused into the integrated multi-index, and the joint cooperation of complementary features significantly reduces the impact of false positive matches, so that effective image retrieval can be achieved. Extensive experiments on five benchmark datasets show that the 3D integrated multi-index significantly improves the retrieval accuracy. While compared with other methods, it requires an acceptable memory usage and query time. Importantly, we show that the 3D integrated multi-index is well complementary to many prior techniques, which make our method compared favorably with the state-of-the-arts.

• Journal of Korea Technology Innovation Society
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• v.15 no.3
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• pp.500-532
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• 2012

This study analyzed the technology innovation strategies of knowledge-based companies in the semiconductor IP industry. The theoretical approaches of this study are to i) the creation, protection and utilization of knowledge and innovation, ii) value creation from innovation, iii) modularity, timing of market entry, and the emergence and competition of standard (dominant design). Based on the theoretical analysis, I presented exploratory research hypotheses. Ultimately, this study examined the proposed hypotheses by conducting case studies on the technology innovation strategy of two leading knowledge-based companies in the semiconductor IP industry: ARM and INTEL. First, knowledge-based companies entering in the early stage of the technology cycle select the vertically-integrated technology strategy because of lower access to complementary knowledge assets, and maintain the vertically-integrated technology strategy despite the environmental change-driven differentiation of industry's value chain. Second, knowledge-based companies entering in the later stage of the technology cycle prefer the contract-based technology strategy because of its increased accessibility to complementary knowledge assets, and choose a different path of innovation strategies depending on whether their asset has the feature of discontinuity or not.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.847-858
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• 2015

Control strategy and corresponding parameters have significant impacts on the overall technical and economic characteristics of composite energy storage systems (CESS). A better control strategy and optimized control parameters can be used to improve the economic and technical characteristics of CESS, and determine the maximum power and stored energy capacity of CESS. A novel coordinated control strategy is proposed considering the coordination of various energy storage systems in CESS. To describe the degree of coordination, a new index, i.e. state of charge coordinated response margin of supercapacitor energy storage system, is presented. Based on the proposed control strategy and index, an optimization model was formulated to minimize the total equivalent cost in a given period for two purposes. The one is to obtain optimal control parameters of an existing CESS, and the other is to obtain the integrated optimal results of control parameters, maximum power and stored energy capacity for CESS in a given period. Case studies indicate that the developed index, control strategy and optimization model can be extensively applied to optimize the economic and technical characteristics of CESS. In addition, impacts of control parameters are discussed in detail.

• Journal of Korean Library and Information Science Society
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• v.51 no.1
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• pp.281-303
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• 2020

The purpose of this study is to structure the system of reading strategy contents and seek a subject linkage method through using it. In order to establish the contents of reading strategy, the 2015 Korean High School Revised National Curriculum's contents system and advanced research were looked at. From that curricula, text areas(the types and fields, meaning structure) and cognitive strategy(reading methods and skills) are deduced and categorized. In addition to reading techniques reorganized by referring to worksheets of advanced researches, the system of reading strategy contents was made. As the result of applying it to the learning activities of "he Integrated Society" and "he Integrated Science" a subject linkage to learn the learning contents proposed providing a variety of reading materials related to the subject and running extended reading programs.