• 품질경영학회지
• /
• 제22권2호
• /
• pp.41-50
• /
• 1994

Consider a canning process where cans are filled with an expensive ingredient. Cans weighting above the specified limit are sold in a regular market for a fixed price, and underfilled cans are emptied and refilled at the expense of a reprocessing cost. In this paper, the effect of measurement error on the determination of the optimal process mean for a canning process is examined. It is assumed that the quantity X of ingredient in a can is normally distributed with unknown mean and known variance, and the observed value Y of X is also normally distributed with known mean and variance. A profit model is constructed which involves selling price. cost of ingredients, reprocessing cost. and cost from an accepted nonconforming can, and methods of finding the optimal process mean and the cutoff value on Y are presented. It is shown that the optimal process mean increases. and the expected profit decreases when the measurement error is relatively large in comparison to the process variance.

• Advances in Energy Research
• /
• 제7권2호
• /
• pp.85-100
• /
• 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.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2000년도 하계학술대회 논문집 A
• /
• pp.279-281
• /
• 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
• /
• 제5권3호
• /
• pp.415-422
• /
• 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.

• 복식문화연구
• /
• 제19권3호
• /
• pp.565-578
• /
• 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.

• 한국정보시스템학회지:정보시스템연구
• /
• 제26권3호
• /
• pp.119-147
• /
• 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.

• 한국항만경제학회지
• /
• 제25권3호
• /
• pp.251-268
• /
• 2009

본 논문은 서비스 품질이 서로 다른 두 항만의 가격경쟁을 게임모형을 이용해 이론적으로 분석하고 있다. 화주들의 위치를 두 가지로 가정하였다. 하나는 두 항만의 한곳에 화주들이 밀집된 경우이고, 다른 하나는 두 항만 사이에 화주들이 고루 배치된 경우이다. 분석결과를 요약하면, 다음과 같다. 화주가 두 항만 사이의 특정 위치에 밀집되어 있을 경우, 화주들의 고품질 서비스에 대한 선호도가 커질수록 두 항만의 가격이 높아지나, 고품질 항만의 가격이 저품질 항만의 가격보다 2배 이상 빠르게 증가한다. 화주들의 위치가 고품질 항만쪽에 가까울수록 고품질 항만의 가격은 올라가고, 저품질 항만의 가격은 떨어진다. 또한, 운송비가 올라가면 저품질 항만의 가격은 낮아지나, 고품질 항만의 가격은 올라갈 가능성이 높다. 고품질 항만의 서비스가 상대적으로 더 높아지면, 고품질 항만의 가격은 올라가고, 저품질 항만의 가격 변화는 불확실하다. 다음으로 화주가 두 항만사이에 균질하게 분포할 경우, 화주들의 고품질 항만 서비스에 대한 선호도가 커질수록 두 항만의 가격이 높아지고, 고품질 항만의 가격이 저품질 항만의 가격보다 2배 이상 빠르게 증가하며, 운송비가 커질수록 두 항만의 가격이 함께 작아지나, 저품질 항만의 가격이 고품질 항만의 가격보다 2배 정도 빠르게 감소해 간다. 또한, 고품질 항만 서비스가 상대적으로 높아지면, 고품질 항만의 가격은 올라가지만, 저품질 항만의 가격은 운송비 수준이 높으면 내려간다.

• 자원ㆍ환경경제연구
• /
• 제23권2호
• /
• pp.187-224
• /
• 2014

본 연구에서는 담합의 경제분석에서 고려해야 할 쟁점들을 논의한 후, 이러한 쟁점들을 반영한 방법론을 특정 수송용 연료시장의 분석에 적용하였다. 가상 경쟁가격과 과잉징수를 산정하는 5가지 방법 중 표준시장비교방법에 기반한 회귀분석방법이 최선이다. 수송용 연료시장에서와 같이 국제가격과 환율이 국내가격에 영향을 미치는 제품의 실거래가격을 분석하는 경우 논리에 부합하면서 유연한 함수형태는 로그-로그 함수형태이다. 경제분석의 대상이 되는 자료가 시계열자료인 경우에 ARDL 모형을 시장별 회귀분석모형의 근간으로 채택하는 것이 필요하며, 표준시장비교방법에 기반한 회귀분석방법에서는 구성 회귀식 간에 모수제약이 포함된 ARDL 회귀식 체계를 구축하고 system FGLS로 추정하여야 한다. Friedman 동질성 검정을 통하여 표준시장 여부를 판별할 수 있다. 통계적 유의성은 불확실성 하에서 입증하고자 하는 명제를 확립하는데 요구되는 최소의 요건이다. 담합관련 소송의 경제분석에서는 민감도 분석은 그다지 유용성이 없으며, 최적모형 선별과정이 더 중요한 절차이다. 위 방법론을 특정 수송용 연료시장의 분석에 적용한 결과, 해당 시장에서는 담합에 기인하는 손해액이 없다는 귀무가설을 기각할 수 없었다.

• Transactions on Electrical and Electronic Materials
• /
• 제18권6호
• /
• pp.350-358
• /
• 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.

• 전기학회논문지
• /
• 제57권7호
• /
• pp.1150-1156
• /
• 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.