• Journal of Industrial Technology
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• v.22 no.A
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• pp.49-57
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• 2002

The accurate wind speed information at the hub height of a wind turbine is very essential to the exact estimation of the wind turbine power performance testing. Several methods on the site calibration, which is a technique to estimate the wind speed at the wind turbine's hub height based on the measured wind data using a reference meteorological mast, are introduced. A site calibration result and the wind resource assessment for the Taekwanryung test site are presented using a one-month wind data from a reference meteorological mast and a temporal mast installed at the site of wind turbine. From this analysis, it turns out that the current location of the reference meteorological mast is wrongly determined, and the self-developed codes for the site calibration are working properly. Besides, an analysis on the uncertainty allocation for the wind speed correction using site calibration is performed.

• Journal of Information Technology Applications and Management
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• v.27 no.1
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• pp.111-123
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• 2020

This paper aims to highlight the importance of employee participation in green management in hotel firms. In particular, the study examined the role of employee participation in green management on cost saving as a hotel's performance indicator. We collected data from senior and general managers in Korean and US hotels. The results of the study supported our hypotheses, showing that the employee participation had a significantly positive relationship with cost savings in hotels. The results of the study also supported other hypotheses, showing that resource conservation and green building management had positive relationships with cost savings in hotels. Therefore, it can be predicted that green management can save cost in hotel firms. Such managerial implications are discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.300-302
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• 2008

For the evaluation of wind resources, numerical simulation was carried out as a tool for establishing wind map around the korean peninsula. Initial and boundary condition are given by 3 hourly RDAPS(Regional Data Assimilation and Prediction System) data of KMA(Korea Meteorology Administration) and high resolution terrain elevation land cover(30 seconds) data from USGS(United States Geological Survey). Furthermore, Data assimilation was adopted to improve initial meteorological data with buoy and QuikSCAT seawinds data. The simulation was performed from 2003 to 2006 year. To understand wind data correctly in complex terrain as the korean peninsula, at this research, Wind map was classified 4 categories by distance from coastline and elevation.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1672_1673
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• 2009

전력계통의 전지역 또는 광역 정전시 빠른 시간내 다시 전력을 공급할 수 있도록 조치를 취하여야 한다. 그러나 시송전에 있어 가장 중요한 자체기동발전소의 무인화로 인해 복구 시간이 지연되고 이 문제점을 해결하고자 자체기동발전소의 원격제어시스템을 완성하였다. 자체기동발전소 비상발전기의 원격제어, 자동동기투입장치의 도입, MMI 설계등과 기존 발전통합시스템과의 연계를 통하여 무인 자체기동발전소의 모든 감시 및 제어를 통합센터에서 가능하도록 구현하였다.

• Environmental and Resource Economics Review
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• v.23 no.4
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• pp.553-581
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• 2014

This paper analyzes competition among service stations in the Korean gasoline market. We consider spatial differentiation as a source of product differentiation as well as the characteristics of the stations and vertical contracts between refiners and retailers as factors causing changes in equilibrium prices in the Korean gasoline retail market. The effect of the government's price disclosure policy on the retail market competition is also analyzed. Moran's I test indicates that the prices of neighboring gas stations are spatially correlated in the market. It is also found that gasoline prices for vertically integrated stations are much lower than those for independent stations. In addition, unbranded stations charge lower prices than branded stations but also induce branded stations to price more competitively. Meanwhile, the government's price disclosure policy did intensify price competition in the retail gasoline market. It is inferred that the price disclosure policy contributed to retailers gaining more bargain power in price negotiation with refiners, causing an eventual increase in retail prices.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.8
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• pp.1074-1079
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• 2013

Demand response(DR) is potential generation alternative to improve the reliability indices of system and load points. However, when demand resources scheduled in DR market fail to reduce demand, it can create new problems associated with maintaining a reliable supply. In this paper, a reliability model of demand resource is constructed considering customers' behaviors in the same form as conventional generation units, where availability and unavailability are associated with the simple two-state model. As a result, the generalized reliability model of demand resources is represented by multi-state model.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.352-354
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• 2011

The performance of multihop cognitive radio networks (CRN) can be improved significantly by using multiple channels in spectrum underlay fashion. However, interference due to the sharing of common radio channel and congestion due to the contention among those flows that share the same links become an obstacle to meet this challenge. How to control efficiently congestion and allocate power optimally to obtain a high end-to-end throughput is a key objective in this work. We reexamined the Network Utility Maximum (NUM) problem with a new primary outage constraint and proposed a novel resource allocation strategy to solve it effectively and efficiently.

• Environmental and Resource Economics Review
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• v.9 no.5
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• pp.903-924
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• 2000

This paper examines the alternative method to measure the state of overall economic activity. The macroeconomic variables, used for business cycle, take more than a month after a period for collection and aggregation. The electricity generation data is compiled in mechanical ways just after the period. Based on this fact, we develop the two stage estimation method for coincident economic indicators in order to detect the business cycle in an earlier period, using Stock-Watson's Dynamic Factor Model. Using monthly data from 1970 to 1999, it is found that the experimental coincidence economic indicators are well-fitted to data and also that the estimates of two stage estimation method have good explanatory power, equivalent to the experimental coincidence economic indicators. While the RMSE of coincidence economic indicators is found to be 1.27%, that of the experimental coincidence economic indicators is found to be 1.31% and that of the two stage estimation method is around 1.44%. If we take consideration into the fact that it measures the business cycle in one month earlier, we come to the conclusion that the two stage estimation is of great use.

• ETRI Journal
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• v.34 no.4
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• pp.613-616
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• 2012

A multi-spot-beam satellite is an attractive technique for future satellite communications since it can support high data rates by projecting high power density to each spot beam and can reuse a frequency in different cells to increase the total system capacity. In this letter, we propose a resource management technique adjusting the bandwidth of each beam to minimize the difference between the traffic demand and allocated capacity. This represents a reasonable solution for dynamic bandwidth allocation, considering a trade-off between the maximum total capacity and fairness among the spot beams with different traffic demands.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.433-436
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• 1996

최근들어 금융산업에 있어서 중요한 패러다임의 전환은 정치 경제질서의 변화에 수반되는 개방화 '자율화 추세이며, 국내 금융기관들은 이러한 전환기를 극복하고자 다양한 경영전략을 구사하고 있다. 그 중에서 가장 두드러져 보이는 것이 경영변화 모색을 위한 정보기술의 활용 촉진이며, 이는 어느 산업보다도 정보강도가 높은 금융기관 있어 경쟁우위를 확보하는데 결정적인 힘을 가진다 할 것이다. 본 논문에서는 이와 같은 배경과 정보시스템 평가이론을 바탕으로 금융기관의 정보인프라 (Information Infrastructure) 수준을 측정하고 이 수준이 금융기관의 경쟁력에 어느 정도 영향을 미치는지에 대하여 고찰하고자 하였다. 연구대상 기관은 국내 예금은행중 선발시중은행, 후발시중은행, 지방은행 등 3그룹에서 각각 3개은행씩을 선정하였으며, 정보인프라 수준을 독립변수로 그리고 업무 생산성을 나타내는 직원1인당 부가가치및 정보화지수를 각각 종속변수로 활용하였다. 연구결과 분명한 것은 금윤산업에 있어서 정보인프라의 효율적인 구축이 경쟁우위를 확보하는데 있어 매우 중요한 전략으로 제시될 수 있다는 것이며, 특히 생산성 향상을 지속하기 위해서는 유형의 자원 (Visible Resource)과 아울러 조직, 인력, 전략 등 무형의 자원 (Invisible Resource)에 대한 정책지원이 폭넓게 이루어져야 한다는 것이다.