• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.1
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• pp.87-99
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• 2004

In this paper, we have developed a technology-service relationship model which describes the diffusion process of a group of services and relevant technologies, and have applied the developed model to the prediction of the number of subscribers to the next generation mobile service. The technology-service relationship model developed in this paper incorporates the developing process of relevant technologies, a supply-side factor, into the diffusion process of specific services, while many diffusion models and multi-generation diffusion models in previous researches are mainly reflect the demand-side factors. So, the proposed model could effectively applied to the telecommunication services where the developing of the relevant technologies are very essential to the service Penetration. In our application, the Proposed model provides a competitive substitution between the next generation mobile service and the traditional mobile service.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1007-1012
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• 2008

Demand for the highly efficient and high performance urban energy supply system having been continuously increased according to the rise of quality of life and continuously increased energy cost all over the world. The district heating and cooling system is very effective way for energy saving, cost reduction, and demand side management of energy. There are several district cooling supply technologies such as chilled water direct transportation, installation of absorption type chiller in the user side, and desiccant cooling. This study investigates the advantage and technical problems of each district cooling technology. Also, it is necessary political and financial support system for the extension of district cooling system.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.8
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• pp.387-394
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• 2005

This paper deals with the grid-interactive small battery energy storage system, which aims at the integration o( power quality improvement and demand side management. The main purpose of the proposed system is to achieve the peak power cutting and to compensate the current harmonics and reactive power at the point of installation on power distribution for residential homes. paper deals with the grid-interactive small battery energy storage system, In this paper, the basic principle and control algorithm is analyzed, theoretically and the design methodology of the system is discussed. To verify the proposed system, a comprehensive evaluation with theoretical analysis, simulation and experimental results for 1 KVA load capacity is presented.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.340-352
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• 2017

In This study, we examined the gap between supply and demand of forest policy by year through big data analysis for macroscopic evaluation of the 5th Basic Forest Plan. We collected unstructured data based on keywords related to the projects mentioned in the news, SNS and so on in the relevant year for the policy demand side; and based on the documents published by the Korea Forest Service for the policy supply side. based on the collected data, we specified the network structure through the social network analysis technique, and identified the gap between supply and demand of the Korea Forest Service's policies by comparing the network of the demand side and that of the supply side. The results of big data analysis indicated that the network of the supply side is less radial than that of the demand side, implying that various keywords other than forest could considerably influence on the network. Also we compared the trends of supply and demand for 33 keywords related to 27 major projects. The results showed that 7 keywords shows increasing demand but decreasing supply: sustainable, forest management, forest biota, forest protection, forest disease and pest, urban forest, and North Korea. Since the supply-demand gap is confirmed for the 7 keywords, it is necessary to strengthen the forest policy regarding the 7 keywords in the 6th Basic Plan.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2117-2123
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• 2008

This paper describes the portal system architecture of large consumers for ESP(Energy Service Provider) to provide customers with various value added services such as monitoring and controlling a wide variety of electric devices in consumer's premises for optimal energy management from both consumer side and ESP side, and the prototype implementation of 2 kinds of value added services. The architecture is composed of the device portal which gathers the information from electric devices and controls them and the consumer portal which can make ESP operate the optimal energy management with two-way communications. The demand side management and energy management functions was chosen and implemented for the prototype system as value added services. The prototype was designed to create, manage, and trace the events about services between ESP and customers.

• Journal of Communications and Networks
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• v.14 no.6
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• pp.662-671
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• 2012

Plug-in hybrid electric vehicles (PHEVs) will be widely used in future transportation systems to reduce oil fuel consumption. Therefore, the electrical energy demand will be increased due to the charging of a large number of vehicles. Without intelligent control strategies, the charging process can easily overload the electricity grid at peak hours. In this paper, we consider a smart charging and discharging process for multiple PHEVs in a building's garage to optimize the energy consumption profile of the building. We formulate a centralized optimization problem in which the building controller or planner aims to minimize the square Euclidean distance between the instantaneous energy demand and the average demand of the building by controlling the charging and discharging schedules of PHEVs (or 'users'). The PHEVs' batteries will be charged during low-demand periods and discharged during high-demand periods in order to reduce the peak load of the building. In a decentralized system, we design an energy cost-sharing model and apply a non-cooperative approach to formulate an energy charging and discharging scheduling game, in which the players are the users, their strategies are the battery charging and discharging schedules, and the utility function of each user is defined as the negative total energy payment to the building. Based on the game theory setup, we also propose a distributed algorithm in which each PHEV independently selects its best strategy to maximize the utility function. The PHEVs update the building planner with their energy charging and discharging schedules. We also show that the PHEV owners will have an incentive to participate in the energy charging and discharging game. Simulation results verify that the proposed distributed algorithm will minimize the peak load and the total energy cost simultaneously.

• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.65-65
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• 2005

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.05a
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• pp.183-188
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• 2001

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.64-64
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• 2007

• Journal of Digital Convergence
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• v.8 no.2
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• pp.103-114
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• 2010

People generally focus on the supply side when conducting a study on the movie industry. However, to understand the movie industry better, one needs to analyze both sides - the demand and supply of movies. This paper analyzes demand-side factors that have long been taken for granted in Korea's movie industry. The study used data for 1991~2008 on the following demand-factors : the average ticket prices, the number of working days and hours, the average personal income, the number of spectators for the two major professional sports, cable TV, the number of movies released each year and the number of movie screens. This study shows that ticket prices do not conform to the law of demand. According to the law of demand, increasing price leads to a decline in demand. However, in reality, the number of viewers went up along with ticket prices. The study found that demand for movies was correlated to income levels and leisure time. An increase in the number of leisure hours and income levels pushed up demand. Contrary to general belief, a growth in the availability of substitutes, such as professional sports(soccer and baseball), did not result in a fall in demand for movies. The audiences for both sports and movies grew simultaneously as the amount of leisure time increased. Contrary to the general expectations that more diversified genres of movies will draw larger audiences by satisfying different individual tastes, the diversification had little impact, but the number of movie screens was positively correlated with audience size. In sum, changes in ticket prices and the quantity of substitutes had little influence on demand in the movie industry. Rather, it was the supply side of the industry that induced demand.