Deok-Joo Lee

A dynamic competition analysis on the Korean mobile phone market using competitive diffusion model

The purpose of this paper is to estimate the demand function of mobile phone subscription in Korea, with an explicit consideration of market competition effects, and to empirically clarify the dynamic competitive relationship between the cellular and PCS services. The demand function was estimated using the Lotka-Volterra model, a famous competitive diffusion model. In addition, the characteristics of the dynamic competitive relationship in the Korean mobile phone market are empirically examined, including the existence of an equilibrium point and its stability with the estimated demand function. The results show that competitive relationship in the Korean mobile phone market exhibits a kind of commensalisms, in which the PCS market benefits from the existence of the cellular market, while the number of cellular subscribers is hardly affected by the PCS market. Furthermore, it is shown that the competition between the cellular and PCS services has a dynamic equilibrium point that is partially stable.

Is HAPS viable for the next-generation telecommunication platform in Korea?

HAPS is a promising technology capable of providing broadband multimedia services as an alternative to the satellite communication system or terrestrial network. In this study, economic aspects of HAPS service are analyzed, HAPS services are defined, and revenues from the defined services are forecasted assuming nine scenarios. Capital expenditure as well as operating expenditure is estimated. To evaluate the profitability of HAPS service, the net present value (NPV), payback period, and the internal rate of return (IRR) are calculated. The results show that HAPS is economically justifiable in all the scenarios. Assuming that ARPU for the service is

Measuring the Efficiency of Investment in the Deployment and Technology Development of Renewable Energy in Korea Using the DEA

35 per month in the average scenario, NPV is calculated as

Optimal Energy Consumption Scheduling in Smart-Grid Considering Storage Appliance : A Game-Theoretic Approach

2964 million, IRR becomes 31.9%, and payback occurs in 2017, which implies that HAPS service is profitable in Korea. In addition, the results of the sensitivity analysis show that the results are fairly robust.

Technological forecasting at the Korean stock market: A dynamic competition analysis using Lotka–Volterra model

Hong-Hee Kim․Deok-Joo Lee․Kyung-Taek Kim ․Sung-Joon ParkDepartment of Industrial and Management Systems Engineering, Kyung Hee UniversityThe purpose of this paper is to analyze the efficiency of government investment in the deployment and technological development of three technological areas - wind power, photovoltaic and fuel cell - of renewable energy in Korea using the DEA (data envelopment analysis). The efficiencies of government investment in renewable energies are measured and compared among three kinds of technologies using the actual data during 2007~2009. In the present DEA model, R&D investment and government subsidies for renewable energy usage promotion are selected as input variables, and the number of patents, supply level, and the production cost as output variable. As a result, it is found that the wind power is the most efficient renewable energy in Korea in the perspective of the efficiency of government investment.

Evaluation of R&D investments in wind power in Korea using real option

In this research, we consider a smart grid network of electricity with multiple consumers connected to a monopolistic provider. Each consumer can be informed the real time price changes through the smart meter and updates his consumption schedule to minimize the energy consumption expenditures by which the required power demand should be satisfied under the given real time pricing scheme. This real-time decision making problem has been recently studied through game-theoretic approach. The present paper contributes to the existing literature by incorporating storage appliance into the set of available household appliances which has somewhat distinctive functions compared to other types of appliances and would be regarded to play a significant role in energy consumption scheduling for the future smart grid. We propose a game-theoretic algorithm which could draw the optimal energy consumption scheduling for each household appliances including storage. Results on simulation data showed that the storage contributed to increase the efficiency of energy consumption pattern in the viewpoint of not only individual consumer but also whole system.