• Journal of Communications and Networks
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• v.16 no.2
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• pp.217-226
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• 2014

In this research, we study the problem of opportunistic spectrum access (OSA) in a time-varying environment with fading channels, where the channel state is characterized by both channel quality and the occupancy of primary users (PUs). First, a finite-state Markov channel model is introduced to represent a fading channel. Second, by probing channel quality and exploring the activities of PUs jointly, a two-dimensional partially observable Markov decision process framework is proposed for OSA. In addition, a greedy strategy is designed, where a secondary user selects a channel that has the best-expected data transmission rate to maximize the instantaneous reward in the current slot. Compared with the optimal strategy that considers future reward, the greedy strategy brings low complexity and relatively ideal performance. Meanwhile, the spectrum sensing error that causes the collision between a PU and a secondary user (SU) is also discussed. Furthermore, we analyze the multiuser situation in which the proposed single-user strategy is adopted by every SU compared with the previous one. By observing the simulation results, the proposed strategy attains a larger throughput than the previous works under various parameter configurations.

• 대한공업교육학회지
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• v.31 no.1
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• pp.129-145
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• 2006

The purpose of this study was to develop and apply the project-based learning strategy in blended learning environment to raise and enhance scientific thinking skill, creativity, and problem solving skills to students who would be teachers of an elementary school in the future. This study was conducted as an action research based on an educational university. The study included 25 participants in a class. Data were collected through observation, surveys, interview and students' artifacts. Results indicated the project-based learning strategy in blended learning environment allowed students to raise problem solving skill, critical thinking skill, and creativity. Finally implications of this study, obstacles to conduct this study, and recommendations to implement this strategy more effectively and efficiently were presented.

• International Journal of Aerospace System Engineering
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• v.5 no.2
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• pp.1-7
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• 2018

This study examines the history of Korean aviation industry and presents the investment strategy based on the evidence and the 4th industrial revolution. Looking at the evolution of the Korean aviation industry and its technological development will be a great help to support industrial and technological innovation in the future. The modern aviation industry is divided into stages of development, focusing on maintenance of equipment introduced in advanced countries, localization through license assembly, production of products based on technology, and international joint development. The development of aeronautics technology has been progressing towards a general improvement of economic efficiency, aircraft safety efficiency through environmental-friendliness, unmanned operation, and downsizing. The Korea Aerospace Research Institute has secured key technologies through development of several aircrafts such as Experimental Aircraft Kachi, EXPO Unmanned Airship, Twin-engine Composite Aircraft, Canard Aircraft, Multi-Purpose Stratosphere unmanned-airship, Medium Aerostats, Smart UAV, Surion, EAV-2H, KC-100, and OPV. The development strategy is discussed at the level of the evidence-based investment strategy that is currently being discussed, and so the investment priorities in aircraft is high. Current drone usage and development direction are not only producing parts using 3D printer, but also autonomous flight, communication (IoT, 5G), information processing (big data, machine learning). Therefore, the aviation industry is expected to lead the fourth industrial revolution.

• East Asian Journal of Business Economics (EAJBE)
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• v.10 no.4
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• pp.39-45
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• 2022

Purpose - This short paper reviews the debate dealing with the relationship between strategy and traditional strategy approach on the one hand, and business models and new business model approach on the other hand and tries to offer useful direction to be more helpful to theoretical discussions. Research design, data, and methodology - This paper makes a theoretical analysis to explain the confusion surrounding the debate, reviewing mainly literature survey papers and finds theoretical conjecture and its limitations in order to present useful direction to the future theoretical work. Result - In order to comprise its diversity, business model studies should consider the characteristics of each firm, sector, and market. Adding further elements which are related to each sector or market, theoretical studies can capture the diverse phenomena related to business model and business model innovation. Conclusion - The traditional strategy perspective can be utilized to the Business model phenomenon in the case of incumbent firms and non-digital sector and existing markets. Meanwhile the new business model perspective can be utilized to business model phenomena in case of start-ups and digital sector and emerging markets. Reconciling two perspectives, the studies dealing with the business model should focus on the characteristics of firms, markets, and knowledge from the perspective of business model innovation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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• pp.115-122
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• 2022

As cable TV, which has been leading the paid broadcasting market, has given the lead to IPTV, which has huge communication capital, its competitiveness is gradually weakening. This study examines the operation status of local cable TV and seeks ways to strengthen competitiveness for survival. To this end, we conducted data analysis such as related statistics, broadcasting industry survey reports, IPTV growth reports, CMB management indicators, paid broadcasting literature data, marketing reports, industry success stories, and marketing mix and SWOT analysis. As a result, four strategies for strengthening the survival competitiveness of local cable TV, namely joint purchase apartment marketing strategy, influencer marketing strategy, relationship marketing strategy, and digital marketing strategy were derived. Therefore, the results of this study can contribute to the improvement of the competitiveness of local cable TV, which has been with local residents through close content, and can be used as basic data for establishing marketing strategies for local cable TV in the future.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.9
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• pp.1535-1542
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• 2007

HTS (High Temperature Superconducting) Power devices has the several useful characteristics from the technical and economical viewpoint. Possible application to the utility industry have been widely discussed in various research projects. For the successful introduction of HTS power devices into power system, establishing a proper R&D and marketing strategies through estimating the future market size are necessary. However, quantitative estimates of how well HTS power devices will serve their markets have been lacking. In this paper, we propose a estimation methodology of future market size for HTS power divices such as cable, transformer, generator, and motor, and also evaluate the future international and domestic market size by using proposed methodology.

• Asian Journal of Innovation and Policy
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• v.5 no.3
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• pp.330-342
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• 2016

This is an interview with Professor Kwang-Hyung Lee, founding Dean of KAIST Moon Soul Graduates School of Future Strategy and founder of the Department of Bio and Brain Engineering of the same university casting two questions about academics. The first question is what pattern is desirable in the evolution of research topics of an academics. While traditional researchers in science and engineering tend to focus on one subject in ever greater depth over time, Professor Lee's research agenda has spanned several new topics by gradually changing the content of the study: from artificial intelligence to bio and brain research, and to creativity development method, further to future study. The second question is about researchers' social responsibility. He has devoted to contributes to industry fields and the nation through academic activities as well as educating several successful business people, founding a new academic department and graduate school of future studies.

• Journal of Distribution Science
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• v.3 no.1
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• pp.91-111
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• 2005

As the environments of world economy have been changed so rapidly, the conditions of marketing and distribution also have been altered. In korea distribution industry has been changed according to the introduction of various patterns of distribution and marketing. Among them the emerging of network marketing, same meaning with multi-level marketing in this research, is a important phenomenon of distribution industry in Korea. Not only it contributes the progress of national economy, especially distribution industry, but also it includes some limitations and criticism from the dissenters. In this paper, the clear definitions and characteristics of network marketing are suggested. And the current situations of network marketing in this country has been analyzed and compared, The future perspectives and problems of this network marketing have been diagnosed and classified for the future development and contribution for national economy. The various alternatives for the future development of network marketing have been studied and suggested in terms of each role of this industry such as distributers, consumers and government. Though this paper has a small contribution, it contains many limitations for research. Therefore it suggest future directions for further research.

• International Journal of Advanced Culture Technology
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• v.12 no.2
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• pp.286-298
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• 2024

The rapid advancement of drone technology has significantly altered the landscape of modern warfare, presenting both opportunities and challenges for military forces worldwide. As drones become increasingly sophisticated, capable of performing complex missions such as reconnaissance, surveillance, and precision strikes, the development of effective air defense systems has become a critical priority. This study examines the current state of drone and air defense technologies, analyzing their impact on military strategies, tactics, and the future battlefield environment. By exploring the patterns of technological evolution, the limitations of existing air defense systems, and the potential consequences of drone proliferation, this research highlights the need for adaptive, innovative approaches to counter emerging threats. The findings underscore the importance of investing in advanced detection and interception capabilities, developing comprehensive counter-drone doctrines, and fostering international cooperation to address the ethical and legal challenges posed by the military use of drones. As the competition between drone and air defense technologies continues to intensify, policymakers and military leaders must proactively engage in shaping the future of warfare to ensure national security and stability in an increasingly complex world.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.163-168
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• 2017

This study empirically examines the differences in attitude and memory effect according to the product knowledge (high knowledge / low knowledge) and temporal distance (near future / far future) in the new product preannouncing strategy of companies through Facebook Respectively. Experiments were conducted by inserting the experiment into a virtual web browser using Facebook 's actual brand fan page and then connecting the experiment to the experimental banner site. As a result of research, when preannouncing new products are released in the near future, low knowledge consumers have made judgments of purchasing decisions because GRM judgments are more favorable than property information (ARM) judgments, but preannouncing is a new product At the time of launch, highly-knowledgeable consumers had a positive effect on the property information (ARM) judgment of the product rather than the comprehensive information (GRM) judgment. In addition, when preannouncing was introduced in the near future, the attitudes of the products between the low-knowledge consumers and the high-knowledge consumers were all positive, but when the new products were launched in the distant future, Product attitude was negative.