• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.6
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• pp.946-954
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• 2016

Energy industry is undergoing a paradigm shift in customer participation in the smartgrid. Customers traditionally consume electrical power. But nowadays not only do they generate electricity from private distributed generations, they can participate in demand response programs with their negawatt power which means a theoretical unit of power representing an amount of energy saved. Therefore development of decision-making criteria for electric load aggregation becomes a greater consideration as an amount of energy saved from demand response resources increases. This paper proposes load aggregators' decision-making criteria in the industrial sector where it made up the largest portion in demand response portfolio in order to assure reliability performance for demand response resources.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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• pp.75-82
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• 2007

When one forecasts urban water demand in a long-term, multivariate model can give more benefits than per capita requirement model. However, the former has shortcomings in that statistically high explanatory power cannot be obtained well, and change in customer behavior cannot be considered. If the past water consumption effects the future water demand, dynamic model may describe real water consumption data better than static model, i.e. the existing multivariate model. On these grounds, this study built dynamic model using system dynamics. From a case study in Seoul and Busan city, dynamic model was expected to forecast water demand more descriptively and reliably.

• Journal of the Korea Safety Management & Science
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• v.8 no.3
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• pp.115-123
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• 2006

The main focus of this study is to investigate the performance of a clark-scarf type multi-echelon serial supply chain operating with a base-stock policy and to optimize the inventory levels in the supply chains so as to minimize the systemwide total inventory cost, comprising holding and backorder costs as all the nodes in the supply chain. The source of supply of raw materials to the most upstream node, namely supplier, is assumed to have an infinite raw material availability. Retailer faces random customer demand, which is assumed to be stationary and normally distributed. If the demand exceeds on-hand inventory, the excess demand is backlogged. Using the echelon stock and demand quantile concepts and an efficient simulation technique, we derive near optimal inventory policy. Additionally we discuss the derived results through the extensive experiments for different supply chain settings.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.856-857
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• 2007

For the sake of a stable power supply, an electric power company must have power generation facilities that can generate more electricity than the maximum demand of the year. Due to the fact that the maximum electricity demand will also continue to increase, enormous investments are needed annually to build power plants. For that reason, electric power companies are propelling 'Demand Side Management' which improve the form of electrical usage for the customer in a positive way. This paper presents the concept of 'Cool Storage System' which is the most representative program, which lowers the peak demand during the on-peak time periods in a day and creates a base load simultaneously during the night time hours among the DSM programs.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.638-644
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• 2008

Mungyeng line(Jupyung${\sim}$Mungyeng) was closed due to a rapid decrease in demand in 1995. However, as the rail transportation demand is expected to increase with the plan to develop a tourist resort and a traffic network in Mungyeng area, it is required to forecast future demand to meet the change of transportation environment in this region. This study predicts the rail transportation demand and analyzes financial benefit in operator's side in case of reopening this line, based on nation-wide traffic volume data from Korean Transportation Database(KTDB). The results of this research can be applied to not only establishing a train operation plan also improving customer service. Moreover, Korail will have an opportunity to develop new business by linking train service to tourist attractions around the Mungyeng area.

• Journal of Korean Society for Quality Management
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• v.35 no.4
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• pp.26-37
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• 2007

The demand of ubiquitous home network system is rapidly increasing in Korea as each construction enterprise makes a huge effort to introduce it to apartment complex. However, the design of home network system is rather technology oriented than the customer focused. Lack of knowledge about customer needs is an obstacle in spreading the ubiquitous home network system to the market regardless of technology development. In this paper, we propose a HCSI(customer satisfaction index for home network system) using an SEM(structural equation model) where structural relationship among several factors influential on users' satisfaction is considered. This model enables to calculate the satisfaction index for target customer group so that one can provide necessary feedback information for improvement of the home network system used for each group.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.4
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• pp.45-60
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• 2005

We consider a vehicle routing problem with time window and dock capacity constraints (VRPTD). In most traditional models of vehicle routing problems with time window (VRPTW), each customer must be assigned to only one vehicle route. However demand of a customer may exceed the capacity of one vehicle, hence at least two vehicles may need to visit the customer We assume that each customer has Its own dock capacity. Hence, the customer can be served by only a limited number of vehicles simultaneously. Given a depot, customers, their demands, their time windows and dock capacities, VRPTD is to get a set of feasible routes which pass the depot and some customers such that all demands of each customer are satisfied Since VRPTD is NP-hard, a meta-heuristic algorithm is developed. The algorithm consists of two Procedures : the route construction procedure and the route scheduling procedure. We tested the algorithm on a number of instances and computational results are reported.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.485-491
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• 2022

The traditional economic order quantity (EOQ) model is analyzed under the basic assumption that the purchase price is paid immediately upon receiving the product. However, product suppliers may allow a certain period of deferral of payment for product purchase costs in order to differentiate themselves from competitors. From the distributor's point of view, such a credit transaction can temporarily divert product purchase costs, resulting in a reduction in inventory investment costs, and ultimately, a factor that lowers the selling price for the purpose of increasing end-customer demand can be. In addition, in that credit transactions are provided for the purpose of increasing the demand of suppliers as a means of differentiation from competitors, it is more general to be allowed flexibly according to the transaction volume. In this regard, assuming that the end customer's demand is represented by a linear decreasing function of the distributor's selling price, this study analyzes a model for determining the distributor's pricing and ordering policies under order-size-dependent delay in payments. For the analysis, we also assume that the inventory is depleted not only by customer's demand but also by decaying.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.3
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• pp.163-172
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• 2019

The paper aims to investigate the impact of the gap between domestic and international gold price on money demand in Vietnam, an emerging economy in the Asian region. We use a quarterly database collected from the first quarter of 2004 to the fourth quarter of 2016. The time-series database includes 52 observations. The money demand is represented by M2; Domestic income is the Gross domestic product at the constant prices of 1994; Inflation rate is calculated by the Customer Price Index from the General Statistics Office of Vietnam. The result confirms the existence of a long-term cointegration relationship between the money demand and the gap between domestic and international gold price as well as some variables including domestic income, inflation, and real exchange rate. The regression results also show that the gap between domestic and international gold price has a positive impact on money demand in the Vietnamese economy. Besides, the domestic income and international gold price have positive impacts on money demand while the inflation and real exchange rate are negatively related in the long run. This proves that the gap between the domestic and international gold price really has a positive impact on money demand in Vietnam during the study period.

• Human Ecology Research
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• v.53 no.3
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• pp.279-291
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• 2015

Fair trade is international trade that pays just wages, supplies stable and eco-friendly products, and supports the sustainable development of economies. This study examined consumers 'cognition of fair trade, product intention of fair trade products, and consumer demand for fair trade education. We compare these variables between Korean and Chinese consumers and explored variables that affect consumers' cognition, purchase intentions and consumer education demand. This study randomly targeted 428 adult consumers in Seoul (219) and Beijing (209) to grasp the demand of customer education and a purchasing intention for fair trade products. The results of this study are as follows. First, participants showed a low cognition of fair trade and purchase intention, while consumer demand for fair trade education on concept, campaign and effect had a comparatively higher level. Chinese consumers showed a higher level of purchase intention, but a lower level of consumer education demand for fair trade concepts. Second, a higher education level resulted in a higher cognition of fair trade by Korean consumers and more experienced Chinese consumers had a higher cognition. Third, the cognition of fair trade affected the purchase intentions positively for both in Korean and Chinese consumers. Finally, cognition and purchase intention showed positive effects of the consumer demand for fair trade education on concept, campaign, and effect.