• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.1-10
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• 2017

With the current global need for eco-friendly energies, the large scale use of Electric Vehicles (EVs) is predicted. However, the need to frequently charge EVs to an electrical power system involves risks such as rapid increase of demand power. Therefore, in this paper, we propose a practical smart EV charging scheme considering a Time-of-Use (ToU) price to prevent the rapid increase of demand power and provide load leveling function. For a more practical analysis, we conduct simulations based on the actual distribution system and driving patterns in the Republic of Korea. Results show that the proposed method provides a proper load leveling function while preventing a rapid increase of demand power of the system.

• IE interfaces
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• v.18 no.2
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• pp.126-135
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• 2005

Since the alcohol involves a wide variety of adverse health and social consequences, there is a strong need for improved estimates on economic costs and benefits of alcohol drinking to reduce the social alcohol abuse and to obtain some useful informations for targeting programs. However, there is no research for the intangible costs and benefits so far that are essential to estimate the real overall costs and benefits incurred by alcohol use. Thus this paper finds out and represents a general model for estimating the intangible costs and benefits by use of alcohol demand curve. The calculated monetary values, as a example, of them in 2002 show as big as 7,900 billion won and 4,200 billion won respectively.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.245-248
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• 1998

In this paper, as a forecasting method, the market survey for forecasting demand is introduced for the estimation of subscriber line demand in the optical access networks. The market survey method for the new multimedia services is attempted to collect information directly from customers using the questionnaires for home-users and business-users in local loops. Analysis rationale of questionnaires is suggested to estimate the number of subscriber lines. Also, two measures are presented to quantify the credibility on survey responses; one is the probability that the customer will use the multimedia services and the other is the rate that the subscriber line demand will be actually realized. The former measure is calculated based on the information on customers and the Logit analysis. The latter is obtained by the degree of customer's knowledge about specific services and the customer's willingness to use the services. Based on the values of two measures, the number of subscriber line demand can be developed for installing the optical access networks.

• Journal of Korean Society of Transportation
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• v.24 no.3 s.89
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• pp.157-165
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• 2006

The Purpose of this study is to analyze telecommunications impacts on travel in a comprehensive system, considering demand, supply, costs, and land use. This study first Presents a conceptual model, considering causal relationships among travel, telecommunications, land use, economic activity, and socio-demographics. Then, based on the conceptual model, the aggregate causal relationships between telecommunications (local telephone calls, toll calls, and mobile phone subscribers) and travel (vehicle-miles traveled and number of transit Passengers) are explored in a comprehensive framework, using structural equation modeling of national time series data spanning 1950-2000 in the U.S. The model results suggest that as telecommunications demand increases, travel demand increases, and vice versa. Additionally. transportation infrastructure and land use significantly affect travel demand.

• Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
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• v.12 no.6
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• pp.627-640
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• 2018

Submetering electricity consumption data enables more detail input of end use components, such as lighting, plug, HVAC, and occupancy in building energy modeling. However, such an modeling efforts and results are rarely tried and published in terms of the estimation accuracy of electricity demand. In this research, actual submetering data obtained from a university building is analyzed and provided for building energy modeling practice. As alternative modeling cases, conventional modeling method (Case-1), using reference schedule per building usage, and main metering data based modeling method (Case-2) are established. Detail efforts are added to derive prototypical schedules from the metered data by introducing variability index. The simulation results revealed that Case-1 showed the largest error as we can expect. And Case-2 showed comparative error relative to Case-3 in terms of total electricity estimation. But Case-2 showed about two times larger error in CV (RMSE) in lighting energy demand due to lack of End Use consumption information.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.833-843
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• 2022

Since the supply and demand of agricultural products are unstable, which causes instability in farm income and consumer prices, the government has sought to mitigate the problems caused by unstable supply and demand by generating and providing agricultural outlook information. However, research should be carried out to increase the quality and utilization of agricultural observation information, because the value of agricultural observation information increases only when more users use this information and apply it to their decisions. In this study, a survey was conducted targeting producers and experts who are users or potential users of agricultural outlook information, and the results were analyzed through quantitative model, specifically importance-performance analysis (IPA) and analytic hierarchy process (AHP). The results show that improvement of promptness was required among the seven items evaluated with regard to agricultural outlook. Also, measures for dissemination of agricultural outlook information and the contents of outlook information should be improved to increase its use. If the quality level and use of agricultural observation information are increased by reflecting the results of the above analysis, decision-making on the supply and demand of agricultural products in Korea will be improved, and it is thought that it will be possible to increase farm household income and stabilize consumer prices through stabilization of supply and demand of agricultural products.

• Proceedings of the KIEE Conference
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• 2007.11c
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• pp.97-100
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• 2007

There are regulations on each building for its classification and It is corresponding determined contract demand. For transformer's capability calculation algorithm, cumulated power information of each customer is used to analysis the correlation between power usage and Demand Rate. By modeling this using Least Square Method, it can be targeted to recognize the pattern of transformer use in the past and make a prediction on it in the future.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.97.1-103
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• 2001

Railway passenger demand forecasts may be used directly, or as inputs to other optimization model which is use the demand forecasts to produce estimates of other activities. The optimization models require demand forecasts at the most detailed level. In this environment exponential smoothing forecasting methods such as Holt-Winters are appropriate because it is simple and inexpensive in terms of computation. There are several initialization methods for Holt-Winters Model. The purpose of this paper is to compare the initialization methods for Holt-Winters model.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.65-67
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• 2003

This paper proposes the cost analysis on the energy efficient equipment when this equipment is participated in the demand-side bidding. Conventional demand-side bidding is exercised through load re-distribution. However if this load reduction is exercised by the use of high efficient equipment, its effect will be assumed to be more economical. This paper analyses this cost-benefit effect of high efficient equipment in the demand-side bidding.

• (The)Korea Educational Review
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• v.14 no.1
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• pp.45-69
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• 2008

Using a sample from Korea Education Employment Panel(KEEP), this study attempts to ascertain determinants of demand for alternative education in Korea. It found that children's gender and duration of computer use exert a strong effect on demand for alternative education. Also, those parents, who show more interest in government's education policy; are less content with the schools their children are attending; and exhibit the higher likelihood of migration for children's education, appear to have the stronger tendency to seek alternative education for their children. Meanwhile, there was a significant difference between male and female students in the factors that influence demand for alternative education. For male students, duration of computer use and the parents' interest in government's education policy tend to matter. For female students, however, health condition seems to be associated with demand for alternative education. For both male and female students, those parents' who are more discontent with the schools their children are attending and/or have the higher likelihood of migration for children's education seem more likely to send their children to alternative schools.