• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.103-109
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• 2009

Aircraft fuel cost is the largest airline expenses in airlines who play a major role in air transportation system. Airlines have been making a great effort to save fuel as much as they can. Among these efforts, the systematic fueling strategy has been taken a growing attention since it is recognized as a very cost-effective fuel management strategy. The systematic fueling strategy is the fuel saving strategy in which extra amount of fuel is loaded to utilize the fueling cost differentiation among the cities where the aircraft operate. In this paper, the aircraft fueling optimization model is proposed. The proposed model is to calculate precise amount of loaded fuel to minimize overall fuel cost assuming that the aircraft routing for all aircrafts and fueling cost in all airports where the aircraft fly are given. Compared with heuristic fueling strategy, the result of the proposed model is promising. Therefore, it is expected that the proposed model plays a major role in fuel management strategy in airline operation.

• Journal of Korean Elementary Science Education
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• v.34 no.1
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• pp.32-45
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• 2015

The purpose of this study is to further develop the strategies using EBS clipbank service and investigate the their effects of the science academic emotion on the student's attitude toward science. Clipbank is service for educational purpose. EBS provides clipbank that holds about 210,000 video clips made from EBS programs. Two class of 6th grade were selected and instructed. Implementing and using the teaching strategies, a test was administered to examine the science academic emotion of the students effects using clipbank teaching. It had two rounds for inspection about operation of the strategies with curriculum. In the second research, by re-supplying a more sophisticated program strategy from first in putting feedback. The result of analyzing the test was as follows. First, elementary teachers can be used in class to take advantage of a variety of educational materials clipbank contents. Result of teachers survey, clipbank teaching was effective and teachers who using clipbank service will be the continue utilize clipbank. Second, the strategy for using clipbank teaching was effective on student's science academic emotion. And strategy was effective significantly different depending on gender. In conclusion, the strategy for using clipbank teaching, made students feel that learning science was interesting. A lot of reseaches give that science can provide the ideas as a metheod to educational web-sites, educational web-sites can provide creative ideas to science learning strategy, but it is still lacking that research can be applied to education specifically on how to. This study will help elementary teachers adjust teaching to help students learn science with positive emotions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.3C
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• pp.267-276
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• 2012

In this paper, we propose the future strategy of convergence IT workforce program through the question analysis of convergence IT promising area. We analyzed the future strategy of convergence IT workforce program from different angles in the aspects of convergence IT promising area, workforce model operation, and infrastructure & system support. Based on this analysis, we suggest the key strategy of each area. As a result, we concluded that the outcome of the proposed strategy is visible when the upper three aspects are efficiently coordinated and the strategy is effectively proceeded. Also, we concluded that selection of promising areas through overall analysis, the necessity of efficient correlation plan establishment among state-industry-university, and the necessity of state-run systematic support and state policy establishment are very important.

• Journal of Korean Society of Transportation
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• v.33 no.1
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• pp.1-13
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• 2015

This study aims to develop a mainline metering strategy considering queue imbalance among lanes that can reduce congestion at a toll plaza section by managing queue caused by mainline metering. The suggested strategy considers simultaneously optimizing the number of cars in merging area and managing queue by lane. This study analyzes the effectiveness of the strategy with respect to the average travel time and the occurrence rate of spillback using the PARAMICS. The results show that the suggested strategy has an effect on reducing congestion and improving operation efficiency at toll plaza. In particular, the congestion become more intensified when the length of waiting space is shorter; however, this study shows that the suggested strategy can relieve the congestion in that condition.

• 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.

• Maritime Security
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• v.1 no.1
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• pp.149-173
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• 2020

While the United States and other Western states are in trouble with COVID-19 crisis, China is continuing its aggressive ocean expansion with its Gray-zone strategy. The Gray-zone strategy, which China uses around the South China Sea, refers to a strategy that promotes a change in international politics by creating an unclear state, neither war or peace. China, which is trying to expand its influence across East Asia, will also try to project a Gray zone strategy on the Korean Peninsula. The possible scenarios are as follows: 1) South Korea is accidentally involved in a dispute in the South China Sea, 2) Military conflicts between South Korea and China is caused by illegal fishing of Chinese boats in Yellow Sea, 3) China tries to interfere with Socotra Rock, 4) Unlikely, but possible in the future that China induce the military conflicts between Korea and Japan on the Dokdo issue. In order to cope with these scenarios, Korea should prepare the following measures from a long-term perspective: the creation of an Asian maritime safety fleet, the integ rated operation of the navy and the coast guard in the framework of the national fleet, and strengthening the conflict control system for China's provocations.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.351-357
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• 2021

At the time when interest in the use of big data is rising in the face of the technological paradigm shift of the 4th industrial revolution, interest in the use of patented big data is increasing, especially as the proportion of intangible assets of companies increases. In addition to quantitative information, patent data contains various information such as unstructured text such as title, abstract, claim, citation and citation relations, drawings, and technology classification. It is judged that the use of treatment is important. Therefore, in this study, in order to systematically operate the innovative patent strategy framework and to secure a competitive advantage by strengthening the fundamental technological competitiveness of the company, we propose a method of using patent big data centering on the case of Company A, and verify its validity. I would like to suggest some implications. Through this, it is intended to raise awareness of the use of patent big data, and to suggest ways to use patent big data in connection with the company's company-wide strategy, business strategy, and functional strategy.

• Industry Promotion Research
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• v.8 no.1
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• pp.35-45
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• 2023

This paper addressed the analysis of the trend and direction of the US defense strategy based on their third offset strategy and presented the practical policy implication of ensuring the security of South Korea appropriately in the future national defense environment. The countermeasures for the development ability of advanced weapon systems and secure core technologies for Korea were presented in consideration of the US third offset strategy for the future national defense environment. First, to carry out the innovation of national defense in Korea based on artificial intelligence(AI), the long-term basis strategy for the operation of the unmanned robot and autonomous weapon system should be suggested. Second, the platform for AI has to be developed to obtain the development of algorithms and computing abilities for securing the collection/storage/management of national defense data. Lastly, advanced components and core technologies are identified, which the Korean government can join to develop with the US on a basis of the Korea-US alliance, and the technical cooperation with the US should be stronger.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.4
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• pp.661-668
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• 2024

Based on the topology of the direct-drive permanent magnet synchronous wind power grid-connected system based on the power electronics full-power converter, the wind turbine model and the grid-side inverter model were studied, and the machine-side rectifier control based on current and speed double closed loops was designed. strategy, as well as a grid-side inverter control strategy based on current and voltage double closed loops, implementing a two-level back-to-back double closed-loop full control strategy. A system simulation model was built using Matlab/Simulink, and the operation of the unit was simulated when the wind speed changed step by step. The grid-connected current with the same phase and good sinusoidal nature of the grid voltage was output. The grid-connected system ran stably and efficiently. The simulation results The validity and rationality of the model, as well as the correctness and feasibility of the control strategy were verified.

• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.10-22
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• 2022

According to the Space Development Promotion Basic Plan, more than 110 satellites are expected to be deployed by 2031. Accordingly, the operation concept and technology for satellites constellation are required, compared to the existing few multi-satellite operations. It is essential to automate and optimize the mission operation system, for efficient operation of the satellite constellation, and preparations are urgently needed for the operation of satellite constellation in domestic as well. In this study, the development direction and strategy of the mission operation system applying automation and optimization for efficient operation of the satellite constellation are proposed. The framework for evaluating the automation level and priority of the mission operation system was developed, to identify the tasks to which automation should be applied preferentially.