• Advances in Energy Research
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• v.7 no.2
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• pp.85-100
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• 2020

Distributed energy resources (DERs) are essential for coping with growing multiple energy demands. A microgrid (MG) is a small-scale version of the power system which makes possible the integration of DERs as well as achieving maximum demand-side management utilization. Hence, this study focuses on the analysis of optimal power dispatch considering economic aspects in a multi-carrier microgrid (MCMG) with price-responsive loads. This paper proposes a novel time-based demand-side management in order to reshape the load curve, as well as preventing the excessive use of energy in peak hours. In conventional studies, energy consumption is optimized from the perspective of each infrastructure user without considering the interactions. Here, the interaction of energy system infrastructures is considered in the presence of energy storage systems (ESSs), small-scale energy resources (SSERs), and responsive loads. Simulations are performed using GAMS (General Algebraic modeling system) to model MCMG, which are connected to the electricity, natural gas, and district heat networks for supplying multiple energy demands. Results show that the simultaneous operation of various energy carriers, as well as utilization of price-responsive loads, lead to better MCMG performance and decrease operating costs for smart distribution grids. This model is examined on a typical MCMG, and the effectiveness of the proposed model is proven.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.279-281
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• 2000

In this paper, we propose that the security-constrined optimal power flow (SCOPF) be solved in a decentralized framework, consisting of regions, using a price-based mechanism. We first solve the distributed OPF problem to determine the maximum secure simultaneous transfer capability of each tie-line between adjacent regions by taking only the security constraints imposed on the tie-lines into account. And then, the regional SCOPF is performed using the conventional LP approach. A description on the inclusion of security constraints with distributed OPF algorithm will be given, followed by a case study for Korea power system.

• Journal of Electrical Engineering and Technology
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• v.5 no.3
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• pp.415-422
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• 2010

The distributed flexible alternative current transmission system (D-FACTS) is a recently developed FACTS technology. Distributed Static Series Compensator (DSSC) is one example of DFACTS devices. DSSC functions in the same way as a Static Synchronous Series Compensator (SSSC), but is smaller in size, lower in price, and possesses more capabilities. Likewise, DSSC lies in transmission lines in a distributed manner. In this work, we designed a fuzzy logic controller to use the DSSC for enhancing transient stability in a two-machine, two-area power system. The parameters of the fuzzy logic controller are varied widely by a suitable choice of membership function and parameters in the rule base. Simulation results demonstrate the effectiveness of the fuzzy controller for transient stability enhancement by DSSC.

• The Research Journal of the Costume Culture
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• v.19 no.3
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• pp.565-578
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• 2011

The purpose of this study was to examine the emotional experience dimension on the brand of the low price cosmetics and to empirically investigate the effect of emotional experience on the relationship between customers and brand. Data were collected for 10 days starting on March $2^{nd}$ 2009. Questionnaires were distributed to 517 female college students who experienced to purchase the products of the low price cosmetic brand and answers were collected. The results of analysis on collected data showed that the emotional experience was classified into sense, spatial environmental emotion, sales promotion emotion, salesperson emotion and visual/verbal identity, and emotional experience on low price cosmetic brand had a positive effect on the relationship between customer and brand. Specifically, it was showed that emotional experience on low price cosmetic brand significantly affected the customer satisfaction, brand trust and brand attachment. In terms of effect of emotional experience on customer satisfaction, the orders in the degree of influence were following: the sense, spatial environmental emotion, sale promotion emotion and salesperson emotions. In terms of effect of emotional experience on brand trust, the orders in the degree of influence were following: the sense, salesperson emotions, sale promotion emotion and spatial environmental emotion. In terms of effect of emotional experience on brand attachment, the orders in the degree of influence were following: the sense, spatial environmental emotion, salesperson emotions, visual/verbal identity and sale promotion emotion.

• The Journal of Information Systems
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• v.26 no.3
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• pp.119-147
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• 2017

Purpose In an online e-commerce environment without face-to-face contact between the seller and the buyer, the attitudes of consumers differ greatly depending on which framing strategy is applied, even in cases when the benefits of the deals represent the same value. The purpose of this study is to explore the effects of price-framing and message-framing strategies on consumer attitudes through an experimental analysis in the context of online travel product purchasing. This study suggests a research model based on prospect theory and prior literature on price-framing and message-framing strategies. Design/methodology/approach The experiment was structured as a 2 (discount price presentation: 'Won' vs. '%') ${\times}$ 2 (discount level: low vs. high) ${\times}$ 2 (time-limit message: none vs. one) mixed design. The research hypotheses were tested in a study of 200 undergraduate and graduate students assigned randomly and distributed evenly to each of the eight cells. Findings The findings indicate that consumer attitudes become more favorable when the '%' discount, higher discount rate, and time-limit message are presented. However, no significant interaction effect is found between the discount price presentation and the discount level/time-limit message. This study has a theoretical implication in that it extends the scope of research by examining the influence of framing strategies on experience goods such as online travel products. Moreover, this study can provide managers with more specific guidelines when establishing framing strategies in the context of purchasing online travel products.

• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.251-268
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• 2009

This study analyzes price competition between two ports theoretically using a game model. We considered two cases: in Case I, consignors are located in a given position, and in Case II, consignors are distributed uniformally between two ports. The results are as follows. In Case I, the higher consignors' preferences for quality are, the more two ports' prices increase. As the locations of consignors are closer to Port H, the price of Port H increases and that of the low quality port(Port L) decreases. In addition, when transportation cost increases, the price of Port L decreases and the price of Port H tends to increase. If the quality of Port H improves, the price of the port H increases but the price of Port L is not clearly determined. In Case II, the higher consignors' preferences for quality are, the more two ports' prices increase. As transportation cost increases, the prices of both ports decrease but the price of Port L decreases twice as fast as that of Port H. In addition, if the quality of Port H improves, the price of Port H increases but the price of Port L decreases when transportation cost is high.

• Environmental and Resource Economics Review
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• v.23 no.2
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• pp.187-224
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• 2014

We present key issues to consider in estimating damages from price-fixing cases and then apply the procedure addressing those issues to a transportation fuel market. Among the five methods of overcharge calculation, the regression analysis incorporating the yardstick method is the best. If the price equation relates the domestic price to the foreign price and the exchange rate as in the transportation fuel market, the functional form satisfying both logical consistency and modeling flexibility is the log-log functional form. If the data under analysis is of time series in nature, then the ARDL model should be the base model for each market and the regression analysis incorporating the yardstick method combines these ARDL equations to account for inter-market correlation and arrange constant terms and collusion-period dummies across component equations appropriately so as to identify the overcharge parameter. We propose a two-step test for the benchmarked market: (a) conduct market-by-market Spearman or Kendall test for randomness of the individual market price series first and (b) then conduct across-market Friedman test for homogeneity of the market price series. Statistical significance is the minimal requirement to establish the alleged proposition in the world of uncertainty. Between the sensitivity analysis and the model selection process for the best fitting model, the latter is far more important in the economic analysis of damage in price-fixing litigation. We applied our framework to a transportation fuel market and could not reject the null hypothesis of no overcharge.

• Transactions on Electrical and Electronic Materials
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• v.18 no.6
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• pp.350-358
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• 2017

Recently, owing to increased interest in low-carbon energy supplies, renewable energy sources such as photovoltaics and wind turbines in distribution networks have received considerable attention for generating clean and unlimited energy. The presence of energy storage systems (ESSs) in the promising field of active distribution networks (ADNs) would have direct impact on power system problems such as encountered in probabilistic distributed generation (DG) model studies. Hence, the optimal procedure is offered herein, in which the simultaneous placement of an ESS, photovoltaic-based DG, and wind turbine-based DG in an ADN is taken into account. The main goal of this paper is to maximize the net present value of the loss reduction benefit by considering the price of electricity for each load state. The proposed framework consists of a scenario tree method for covering the existing uncertainties in the distribution network's load demand as well as DG. The collected results verify the considerable effect of concurrent installation of probabilistic DG models and an ESS in defining the optimum site of DG and the ESS and they demonstrate that the optimum operation of an ESS in the ADN is consequently related to the highest value of the loss reduction benefit in long-term planning as well. The results obtained are encouraging.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.7
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• pp.1150-1156
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• 2008

This paper introduces the PC clustering of the SIMD structure for a distributed processing of on-line contingency to assess a static security of a power system. To execute on-line contingency analysis of a large-scale power system, we need to use high-speed execution device. Therefore, we constructed PC-cluster system using PC clustering method of the SIMD structure and applied to a power system, which relatively shows high quality on the high-speed execution and has a low price. SIMD(single instruction stream, multiple data stream) is a structure that processes are controlled by one signal. The PC cluster system is consisting of 8 PCs. Each PC employs the 2 GHz Pentium 4 CPU and is connected with the others through ethernet switch based fast ethernet. Also, we consider N-1 line contingency that have high potentiality of occurrence realistically. We propose the distributed process algorithm of the SIMD structure for reducing too much execution time on the on-line N-1 line contingency analysis in the large-scale power system. And we have verified a usefulness of the proposed algorithm and the constructed PC cluster system through IEEE 39 and 118 bus system.

• The Journal of the Korea Contents Association
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• v.17 no.8
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• pp.162-174
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• 2017

Product Certification Marks can be used as reliable information in terms of product quality to consumers. This study focuses on how each product attitude of consumers in Korea and China can be changed depending on attachment of product certification mark. Based on nations, product certification marks, and price levels, eight types of questionnaire are distributed and collected where the respondents are allowed to answer product attitudes of two different products in oder to minimize the effect of the product characteristic. As a result, the product attitude of Korean consumers has been showed to more depend on product certification mark than that of Chinese consumers does. The moderating effect of price has been stronger on Chinese consumers than on Korean consumers, and in the case of high price there has been a distinct gap between two countries. This study has its meaning in the way of that the product certification mark has been considered in relation to price level and differently affected product attitude between two countries.