• 설비공학논문집
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• 제20권9호
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• pp.581-589
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• 2008

The pulverized coal combustion behavior in the utility boiler is very complex since so many physical and chemical processes happen in it, simultaneously. The mixing of pulverized coal with combustion air plays an important role in achieving the efficient combustion and stable boiler operation. The distribution of combustion air supplied to the furnace through the windbox damper system has not been clearly known since the individual measurements of air flow for each air nozzle were not possible, yet. The present study describes the CFD modelling of windbox damper system and aims to obtain the air flow rates and pressure loss coefficients across the present five damper systems, respectively. The one dimensional flow network model has been also established to get air flow distributions across the windbox damper, and applied to the actual plant operation condition. Compared with the designed air flow distribution, the modelled one gives a reasonable agreement. For the actual plant operation, the predicted air flow distribution at each air nozzle is differed with the designed data and strongly affected by the individual opening angle.

• Korean Chemical Engineering Research
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• 제45권3호
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• pp.234-241
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• 2007

공장의 안정적인 운전과 경제성을 위해서는 유틸리티의 수급을 정확히 파악하고 공급하는 것이 중요하다. 모터/터빈 공정은 유틸리티 플랜트에서 수증기와 전력의 균형을 조절하여 주며 이의 최적 운전은 유틸리티 플랜트의 경제성에 지대한 영향을 미친다. 모터/터빈 공정의 분석을 위해서는 먼저 수증기 발생장치와 수증기 분배장치 전반에 대한 모델의 규명이 요구됨은 물론 제반 상황에 대한 운전지식이 필요하다. 유틸리티 관련 장치의 모델과 운전지식 베이스를 기반으로 구성되는 모터/터빈 운전 최적화 시스템에서는 다양한 등급의 수증기 헤더에서 요구되는 수증기 양이 변할 때 각 유틸리티 설비의 최적 운전조건을 제시하여 주며 수증기 요구량의 변화에 따라 유틸리티 펌프의 구동원이 적절하게 선택되고 이에 따라 전체 유틸리티 플랜트의 조업 경비도 절감할 수 있다.

• 전기학회논문지
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• 제56권3호
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• pp.491-497
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• 2007

As dispersed generators was driven in condition interconnecting with utility, it could cause a variety of new effects to the original distribution system that was running as considered only the one-way power flow. Therefore, the protection devices that is builted in distribution system should be designed to be able to operate with disposing of not only a fault of the generator, but also utility condition. Especially, the fault of the feeder interconnected with Dispersed Generator can cause the islanding phenomenon of open DG(Dispersed Generators). This phenomenon has many problems such as a machinery damage, electricity qualify degradation and a difficulty of the system recovery. In the fault therefore, we must separate Dispersed Generator from the system quickly. In this paper, for the fault classification of the interconnected DG and the outside feeder we judge the fault of the interconnected DG and the outside feeder in HMI through data provided by IED(Intelligent Electronic Device) on the network and decide whether it operates or not by sending the result to each relay.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.418-419
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• 2011

Recently, the korea power quality standard has been established based on the IEC Std. By IEC Std., the power quality assessment point is measured in PCC. In this case, the utility has to construct PQM system in all customer PCC point and the PQ meter cost would be very high in order to acquire the suitable data. Accordingly the utilities could not apply to PQM system in the distribution power system by the cost and communication problem. In this paper, the proposed economical PQMS(Power quality monitoring system) of Utility.

• 유통과학연구
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• 제16권2호
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• pp.67-81
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• 2018

Purpose - Recently the importance of green consumption and corporate social responsibility has been increasing, thereby enhancing the importance of green consumption space as well. The retail space, as a representative consumption space, is now consuming more energy by introducing bigger retail space, 24-hour operation, cutting-edge equipment, and manless checkout system. Especially for retailers, who are constantly interacting with consumers, not only the economic consideration but also the consumer experience via retail service and physical retail space is crucial for their success. Therefore, this study intends to understand the main factors of motivating consumer perception about green retail space. In addition, we further investigate the mediating and moderating variables to encourage revisit intention and green retail space image. Research design, data, and methodology - In order to test our hypotheses with two models, we conducted a survey using questionnaires. In model 1, 356 respondents were surveyed to determine whether consumers' green attitudes and behaviors enhance environmentally friendly perception on retail space properties. In model 2, a questionnaire survey was conducted on 69 consumers who have experience in green retail space. Questionnaire surveys were conducted with on-line panels in Korea and analyzed using regression model and Hayes' PROCESS macro. Results - We found that consumers with green attitude put more importance on the attributes of green retail space. Also, the utility of the green retail space was found to be significant in emotional and social benefits. And, the consumers, who perceived the importance of green retail space, show higher revisit intentions. The emotional and social utilities have significant positive effects on revisit intention through green retail space image. Conclusions - This study demonstrates that a green retail space can induce positive consumer utility, thereby increasing green retail space image and revisit intention. Thus, in order to increase the image and revisit, retailers should communicate green messages with consumers, enhance green attributes of retail space, and target green consumers. To do so, we suggest that various marketing efforts such as publicity and education are needed to appeal experiential green products and retail space to consumers.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 한국생물과학협회 학술발표대회
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• pp.162.1-162
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• 1998

No Abstract, See Full Text

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2001년도 추계학술대회 논문집
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• pp.271-279
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• 2001

• 전기학회논문지
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• 제60권2호
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• pp.266-272
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• 2011

Real Time Pricing(RTP) is used not only to stabilize the price volatility in electricity market, but to hedge the price risk for Load Serving Entity(LSE). This paper presents an efficient method to reduce the risk of the price volatility in real-time electricity market. For designing the RTP, load patterns of customer are calculated by applying the demand elasticity and customer's utility is also analyzed to compute the RTP revenue through the risk-attribute of the LSE. In the end, the distribution of the LSE's profits can be evaluated to lead the optimal RTP value, depending on the level of customer's participation. Results from the case study based on PJM data are reported to illustrate the proposed method.

• 전기학회논문지
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• 제56권12호
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• pp.2059-2064
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• 2007

This paper analyzed distribution network reliability related with the increment of outages and duration time according to distribution facilities increasing. KEPCO introduced distribution automation system in 1998 which could recognize outage section by remotely monitoring the fault current and reduce the blackout area by remotely controlling distribution switches. As the result of this outage time reduction using distribution automation system, the minimum distribution automation rate was fined out in this paper on the base of analyzing diverse data and how many switches were used in distribution system to improve distribution network reliability at the situation of distribution facilities increasing. This result can be used as the model that an overseas utility company applies distribution automation system in the future.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.489-491
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• 2000

A DAS(Distribution Automation System) enhances the efficiency and productivity of a utility. It also provides intangible benefits such as improved public image and market adventages. This paper discusses an approach to the integration of NDIS(New Distribution Information System) and DAS that will allow benefits from both technologies to support a common database and distributed computing architecture, thereby improving the ability of many functions to justify implementation of integrated systems based on transferring' data comparisons.