• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.481-489
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• 2009

The objective of this research is to provide more reliable and accurate unit factor of water amount by investigating of informations related to various educational institutions such as elementary, middle, high schools and university. In order to estimate the water demand of educational institutions, first of all, the informations such as building area, site area, total school population, and water amount of various educational institutions are investigated to estimate the water unit factor. In this research, we used the total population of students and teachers to estimate the water demand of educational institutions. The results of unit factors of this research are as follows: 1) The elementary school is $0.027983m^3/person{\cdot}day$, 2) middle school: $0.024106m^3/person{\cdot}day$, 3) high school: $0.041415m^3/person{\cdot}day$, 4) specialized high school (science high school and foreign language high school): $0.156938m^3/person{\cdot}day$ and 5) university: $0.033766m^3/person{\cdot}day$. Finally, these water amounts calculated by unit factors were compared with real water amount of educational institutions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.4
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• pp.59-66
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• 2020

In this study, we consider the problem of forecasting the number of inbound foreigners visiting Korea. Forecasting tourism demand is an essential decision to plan related facilities and staffs, thus many studies have been carried out, mainly focusing on the number of inbound or outbound tourists. In order to forecast tourism demand, we use a seasonal ARIMA (SARIMA) model, as well as a SARIMAX model which additionally comprises an exogenous variable affecting the dependent variable, i.e., tourism demand. For constructing the forecasting model, we use a search procedure that can be used to determine the values of the orders of the SARIMA and SARIMAX. For the exogenous variable, we introduce factors that could cause the tourism demand reduction, such as the 9/11 attack, the SARS and MERS epidemic, and the deployment of THAAD. In this study, we propose a procedure, called Measuring Impact on Demand (MID), where the impact of each factor on tourism demand is measured and the value of the exogenous variable corresponding to the factor is determined based on the measurement. To show the performance of the proposed forecasting method, an empirical analysis was conducted where the monthly number of foreign visitors in 2019 were forecasted. It was shown that the proposed method can find more accurate forecasts than other benchmarks in terms of the mean absolute percentage error (MAPE).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.5843-5849
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• 2015

This study analyzes the factor demand structure of sweet persimmon as a part of finding out cost cutting measures. Income and cost data from 2001~2013 Agricultural Income Survey are used for placing the translog cost function and estimating price elasticies and cross elasticities of labor, capital and intermediate input. The result shows that own price elasticities of all factors are small in absolute terms. Additionally the result indicates capital and intermediate input cannot be a substitution for labor, which is a top-line cost-share. It means that the demand for labor cconstitutionally can't be reduced in a short time. This implies that cost reduction should be done focusing on intermediate input, particularly on fertilizer and materials which have higher price elasticity of demand.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.3
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• pp.203-212
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• 2009

The bullwhip effect refers to the phenomenon where demand variability is amplified when one moves upward a supply chain. In this paper, we exactly quantify the bullwhip effect for cases of seasonal demand processes in a two-echelon supply chain with a single retailer and a single supplier. In most of the previous research, some measures of performance for the bullwhip effect are developed for cases of non-seasonal demand processes. The retailer performs demand forecast with a multiplicative seasonal mixed model by using the minimum mean square error forecasting technique and employs a base stock policy. With the developed bullwhip effect measure, we investigate the impact of seasonal factor on the bullwhip effect. Then, we prove that seasonal factor plays an important role on the occurrence of the bullwhip effect.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.6
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• pp.74-79
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• 2002

This paper shows a reasonable design standard factor in commercial buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, electric power consumption, load characteristic, etc., for 23 commercial buildings. With a rapid growth of national economics with the development of intelligence society , electrical energy consumption markedly increased Expecially, it is increased electrical energy consumption in the commercial buildings and thus an energy conservation through efficient use of electricity became more important In our country, the estimation of demand factor and electric equipment capacity are not properly and thus the application of these factors are confusing and different in each electric design of the field.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.36-46
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• 2010

The purpose of this research was to derive political suggestion to increase the demand for forest visit by analyzing the demand of forest visitors, focusing on the residents of Seoul and capital areas. The determinants of demand, which is the number of forest visit in a year, were analyzed by independent variables; six factors from factor analysis on selective attributes, demographic characteristics, and other variables related with the general matters when visiting a forest. As a result, among the independent variables, selective attribute (tourism resource factor), gender (male), and residency (Seoul) were found out to have positive(+) effect on demand for forest visit. However, other selective attribute (external factor of forestry), occupation (white-collar employee), and level of education (over college graduate) were found out to have negative(-) effect on demand for forest visit. Based on these results, implications for the expansion of demand for forest visits were derived.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.331-336
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• 2005

It is increased electrical energy consumption with the development of intelligence society in the office buildings and thus an energy conservation through efficient use of electricity became more important. This paper shows a reasonable design demand factor in office buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, peak power consumption, demand factor, etc., for 54 office buildings and 34 electrical design offices. In this dissertation, it is necessary to analyse the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried linear and nonlinear regression analysis.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.289-291
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• 2000

In a competitive electricity power market, the price of electricity changes instantly, that of conventional market is predetermined and hardly changes. In such a new environment, customers' behaviors change instantly according to the changing electricity prices. If we develop a electricity load model that well describes the behavior of electricity consumers, we can utilize that model in forecasting the amount of future load, solving the load flow problem and finding the weak point of the system. In this paper new electricity model that considers the price of electricity and power factor of the load is presented. While conventional load model, which is demand function of electricity, uses the price of real and reactive power as the independent variable of the demand function. this new load model uses price of real power and penalty factor according to the power factor for the calculation of amount of electricity demand.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.6 no.3
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• pp.57-62
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• 1992

In this paper, the reasonable design standard of Demand Factor for large office buildings is introduced that was made by the statistical way considering actual conditions, such as investigated electrical equipment capacity, electrical power consumption, etc. The results are as follows. 1) It is shown that th saving of electrical equipment investment, the decrease of power loss, the improvement of facilities utilization and the decrease of electrical power rates can be contributed by the application of the design standard. 2) The effect of reduction is showed to confirm the practical use of the proposed reference Demand Factor, and also, it is believed that this proposed reference Demand Factor will be useful in electrical equipment operation and planning.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.15 no.1
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• pp.78-83
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• 2001

To establish the optimized capacity of power transformer, this paper proposed the total demand factor of power supply facility. For this purpose, it was measured and analysed the operating pattern of power supply acility Installed in the apartment. As a result, it is found that the demand factor of each facility is following that : i) In case of [Xlwer water suwly facility ; 47[%], ii) In case of waste water facility ; 44[%]. Also, it was analysed that the optimized total demand factor of power load is proper 42[%1 than 52[%] to lead the efficiency operation.ration.