• KEPCO Journal on Electric Power and Energy
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• v.5 no.4
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• pp.275-286
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• 2019

This paper presents real-time Direct Current (DC) network analysis applications for operation of DC distribution system or DC microgrid. These applications are installed on central Energy Management System (EMS) and provide solutions of DC network operation. To analysis DC distribution network, this paper proposes composition and sequence of applications. Algorithm of applications is presented in this paper. Demonstration tests are performed on DC distribution site in Gochang Power Testing Center of Korea Electric Power Corporation (KEPCO). To verify the performance, developed DC applications installed on EMS. Scenarios for demonstration test of voltage control are presented. Finally, measured data, application output data and simulation data (by PSCAD/EMTDC) are compared and analyze accuracy of applications.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.32-45
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• 2013

Globally, intelligent vehicles and telematics research and development through the integration of IT technology in the vehicle are significant increasing. Real-time data communication for intelligent transportation system (ITS) is very important. It collects real-time data from the vehicle and provides the information collected from ITS center. We propose an effective and secure communication scheme for these communication procedures. In particular, our proposed SIP-based MVPN reduces signaling cost and has many advantages in security aspects. In addition, our proposed scheme performs the mobility management applying NEMO (Network Mobility) for the communication between the vehicles. In other words, we propose an ITS communication mechanism of SIP-based mobile VPN and V2V NEMO. Finally, our performance analysis show that the ITS of SIP-based MVPN is significantly reducing the handoff signaling cost.

• International Commerce and Information Review
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• v.3 no.2
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• pp.93-111
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• 2001

The purpose of this paper is to study the mechanism of Acquisition of Customer Knowledge through Web Site at Global Electronic Commerce Times in Korea. The major findings of this paper is that the models of inter-business alliance network for EC based on contents, types of participating company, categories of business of participating company, modes of alliances, and concentrated industry or function are various and complex. Therefore all companies should know this result and reflect in their business strategy.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.258-266
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• 2018

The purpose of this study was to investigate the current status and the perception of hospice and palliative care program coordinators regarding the use of music in bereavement care in Korea. Both on-line and off-line questionnaires were distributed to program coordinators in 91 institutions, and 54 responses were analyzed by descriptive statistics and Mann-Whitney U test. Even though 92.6% of the participants currently provide a form of bereavement care and 51.9% utilize music as a part of their bereavement program, only 20.3% indicated that their bereavement programs were adequate to address the issues involved, suggesting a need for improvement. As the perceived necessity of bereavement care(4.52) and music therapy based bereavement care(4.20) were generally high, this study supports the need for further development of both forms of bereavement care in Korea.

• Journal of The Korean Association of Information Education
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• v.25 no.2
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• pp.387-403
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• 2021

The purpose of this study is to design a community-based career education app for college students. Currently, career education in universities has various problems. First, career education is not systemized, second, satisfaction of participating students is not high, and third, competency-based career education is not conducted. Designing a community-based career education app for college students will solve the problem of lack of college career education instructors and increase the satisfaction of students participating in career education. To this end, core values were derived through the results of demand surveys, literature analysis, and network text analysis for college students, and a prototype of the app was devised according to the design of the rapid prototype. The career education program to be used in the app was designed by dividing online and offline activities so that university students can execute them in units of learning communities. Through the first and second usability evaluation and expert evaluation, the final prototype was designed and the app screen was designed.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.789-802
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• 2022

The purpose of this study is to present implications for effective operation of domestic school-based mental health services by comparing those in Singapore the United States, Australia. Based on reviewing the public data and previous article, researchers conducted a comparative study on the background, history, goal, and managing process of overseas and domestic organizations. The result of comparison in overseas cases suggests that the foundation of school-based mental health project was laid with the national health plan and detailed frame work for implementation. It was also discussed that domestic school-based mental health project is still in introduction stage, while foreign services were delivered efficiently through the leading agency and the cooperation between government ministries and institutions were active. It suggests that cooperation between government ministries, preparation of an effective operating system, and various approaches for students, guardians and teachers are need for domestic school-based mental health project.

• Journal of the Korea Society of Computer and Information
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• v.29 no.5
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• pp.143-153
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• 2024

This study aims to analyze both the current utilization of e-learning in the scuba diving education sector and the possible improvements by using Delphi analysis. The study administered three rounds of Delphi surveys with 25 specialists, including business executives and educational leaders from scuba diving centers and resorts affiliated with organizations that conduct scuba diving education through e-learning. The comparative analysis of the state of e-learning utilization and factors for improvement revealed significant insights. In terms of expected benefits, the analysis highlighted an increase in user convenience, temporal flexibility in learning activities, and easy access to products. However, it identified major issues such as the simplistic mandatory exams, inadequate professional depth in the feedback provided, and a lack of bidirectional communication between learners and instructors. Recommendations for improvements included enhancing communication through various online communities, conducting mandatory exams offline, and developing a variety of content. Conducting regular program quality evaluations, integrating with various diving communities, and assigning dedicated tutors were deemed crucial factors for future development.

• Geophysics and Geophysical Exploration
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• v.26 no.2
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• pp.52-61
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• 2023

The use of ultra-high-resolution (UHR) seismic surveys to preceisly characterize coastal and shallow structures have increased recently. UHR surveys derive a spatial resolution of 3.125 m using a high-frequency source (80 Hz to 1 kHz). A digital streamer system is an essential module for acquiring high-quality UHR seismic data. Localization studies have focused on reducing purchase costs and decreasing maintenance periods. Basic performance verification and application tests of the developed streamer have been successfully carried out; however, a comparative analysis with the existing benchmark model was not conducted. In this study, we characterized data obtained by using a developed streamer and a benchmark model simultaneously. Tamhae 2 and auxiliary equipment of the Korea Institute of Geoscience and Mineral Resources were used to acquire 2D seismic data, which were analyzed from different perspectives. The data obtained using the developed streamer differed in sensitivity from that obtained using benchmark model by frequency band.However, both type of data had a very high level of similarity in the range corresponding to the central frequency band of the seismic source. However, in the low frequency band below 60 Hz, data obtained using the developed streamer showed a lower signal-to-noise ratio than that obtained using the benchmark model.This lower ratio can hinder the quality in data acquisition using low-frequency sound sources such as cluster air guns. Three causes for this difference were, and streamers developed in future will attempt to reflect on these improvements.

• Journal of the Institute of Convergence Signal Processing
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• v.2 no.3
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• pp.16-23
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• 2001

In this paper, we propose the pseudo n-gram language models for speech recognition with middle size vocabulary compared to large vocabulary speech recognition using the statistical n-gram language models. The proposed method is that it is very simple method, which has the standard structure of ARPA and set the word probability arbitrary. The first, the 1-gram sets the word occurrence probability 1 (log likelihood is 0.0). The second, the 2-gram also sets the word occurrence probability 1, which can only connect the word start symbol and WORD, WORD and the word end symbol . Finally, the 3-gram also sets the ward occurrence probability 1, which can only connect the word start symbol , WORD and the word end symbol . To verify the effectiveness of the proposed method, the word recognition experiments are carried out. The preliminary experimental results (off-line) show that the word accuracy has average 97.7% for 452 words uttered by 3 male speakers. The on-line word recognition results show that the word accuracy has average 92.5% for 20 words uttered by 20 male speakers about stock name of 1,500 words. Through experiments, we have verified the effectiveness of the pseudo n-gram language modes for speech recognition.

• Journal of Practical Engineering Education
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• v.5 no.2
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• pp.139-149
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• 2013

In this paper, we proposed a new Korean Dual system, K-Dual System, and discussed the concepts and details about three sub-models of the system, IPP, W3 and corporate university models. Propose K-Dual system is a new and unique educational model that combines academic study and industrial work in order to solve the various problems of existing work-study parallel educational systems in Korea. K-Dual System has two tracks, Academic and Vocational tracks. Academic track has a long-term field experience training program, IPP program. On the other hands, Vocational track can be divided into two sub-models and those are $W^3$ and corporate university. Finally, we summarized several key points for the successful setup and operation of K-Dual system.