• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2414-2416
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• 2004

Power Companies worldwide are undergoing tremendous change in the Automation issues. It becomes a worldwide trend that the power utilities focus their attention to the automation of their power plants and substation systems, employing recent advanced communication protocols. In this paper, we discuss the standard communication protocols which can be applied in the automation systems to help utilities reduce their operation and maintenance costs while at the same time meeting new requirements for communications to RTUs and intelligent electronic devices(IEDs). Especially, we introduce EC 61850 protocol which is developing for international standard by IEC.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.222-229
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• 1993

The purpose of this study was investigated kinds and utilities of Jeot-kal(fermented fish products) in 55 different regional area which were classified three temperature zone. The result were as follows ; (1) 95 kinds of jeot-kal found, they were subdivided 4 groups according to types and part of fish used : whole fish(46 kinds), vicera(11 kinds), shellfish(14 kinds), mollusca(4 kinds) and crustaceans(20 kinds). 17 kinds of jeot-kal were found in all area. (2) They were used as side dish, seasoning substitution of soy sauce or vinegar and important materials of kimchi. In Kimchi, 49 kinds of jeot-kal were used and Myeolchi Jeot(self-fermented enchovy) was prefered at southern area, saewoo jeot (self-fermented small shrimp), gonjengi jeot(self-fermented Mysis), hwangsegi jeot(self-fermented Hwangandali) were prefered at nouthern and middle area. Sometimes they were used in sacrified service. (3) Salt content and pH of jeot-kal at southern area were higher than other area.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.10
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• pp.1703-1711
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• 2010

Electric power utilities are facing increasing uncertainties regarding the economic, political, societal, environmental constraints under they operate and plan their future systems. The utilities have to integrate consumers' interruption cost representing reliability worth of electricity into the process of determining the optimum investment level. In order to do so, the estimated outage cost must be included into quantitative index corresponding to system capital and operation investment cost to establish an optimal expansion plan. This paper is a study on the outage cost assessment by using macro approach for calculating IEAR(Interrupted Energy Assessment Rates) and the TRELSS(Transmission Reliability Evaluation for Large-Scale Systems) program was used to calculate EENS(Expected Energy Not Served).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.11
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• pp.76-83
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• 2009

In today's competitive power market, electric power utilities have strived to provide energy at an acceptable level of quality due to increased expectations from customers. For this reason, electric power utilities have invested in electric equipment and new techniques. That is the Distribution Automation System (DAS). A merit of DAS is the ability to reduce outage time because of fast service restoration. However, DAS is usually installed in outdoor environments. Therefore, their efficiency is affected by the external conditions. Lightning creates varying degrees of physical stress on DAS. This paper focuses on the reliability of DAS for lightning. Four application studies were performed to compare the reliability indices.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.296-299
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• 2008

In the present research, the exclusive analysis system based on the CFD method were suggested to predict the fire-suppression performance of water mist fire-suppression equipments for design applications. The computing scope is ranged from starting pump to fire-suppression equipments, composed of three parts that calculation of flow rate and pressure distribution at each nozzle, examining of spray performance and predicting of fire-suppression performance in the fire space. Application were done to the fire-suppression system for electric power generation plants. The results were analyzed by comparison between numerical results and initial design conditions in terms of thermal and fluid mechanics.

• Journal of the Korean Institute of Landscape Architecture
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• v.24 no.3
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• pp.29-41
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• 1996

The purposes of this study were to develope some techniques which can be used in the landscape simulation process using PC based computer grahics. As a result, a couple of utilities were programmed in AutoLISP language. The one(DSLINE.LSP) is to digitize 2-dimensional structuer forms in the interactive mode considering error handling, and the other one (IMPOST.LSP) is for superimposing and visualizing the digitized plan data to 3-dimension solids & surfaces referring to topographic elevations of meshes in digital terrain model. By applying utilities to present site, the followings may be described. 1) The utility DSLINE.LSP for digitizing simplified building structure form were proved to be easy to input data of polygons including orthogonal edges by handling user coordinates system and checking invalid intersection and default colsing. 2) IMPOST.LSP utility for superimposing and visualizing tool were proved to be more complicated and speedy in calculating process compared with a practical application of modeling tool before rendering process in landscape simulation of built environment on topographic relief, on specially mesospace level of assessment.

• Korean Journal of Geomatics
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• v.1 no.1
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• pp.75-83
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• 2001

Due to the fast industrial growth and unplanned urban underground development in Korea, systematic management for water lines could not be accomplished. Unsystematic water line management has resulted in difficulty in finding the exact location and the age of the lines, which has the potential of leading to a disastrous situation. The objective of this study is a development of safety management system for water lines using GIS. This system is constructed to easily estimate water line deterioration by the geographic output system on it, search for damaged objectives near the surrounding area in a situation of destruction, and offer the emergency information by which one can quickly take action. Also, it is constructed to prevent accidents from occurring during work by presenting underground utilities and states of work.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.207-209
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• 2001

Intensive competition in the electricity market and demand for higher quality service force the utilities to change their strategies in setting price and quality combination. As cost-up by homogeneously enhancing the electricity service quality may reduce their competitiveness, differential service is to be taken into consideration. Priority Service, which provides customers with a selection of service options at a range of prices and reliability for all or portions of their loads, has drawn attention from utilities in an increasingly competitive environment. Priority Service is to enlarge service options for customers who have diverse needs for supply reliability. This paper in the light of this point reviews differentiated strategy of power quality in the U.S.A.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.77-82
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• 2001

As electric power systems have been moving from vertically integrated utilities to a deregulated environment, the charging of reactive power management is a new challenging theme for market operators. This paper proposes a new methodology to compute the costs of providing reactive power management service in a competitive electrical power market. The proposed formulation, which is basically different from those shown in the literature, consists of two parts. One is to recover investment capital costs of reactive power supporting equipment based on a reactive power flow tracing algorithm. The other is to recover operational costs based on variable spot prices using the optimal power flow algorithm. The charging shapes resulted from the proposed approach exhibit a quite good meaning viewed from a practical sense. It turns out that reactive power charges are mostly due to recovery of capital costs and slightly due to recovery of operational costs. The method can be useful in providing additional insight into power system operation and can be used to determine tariffs of a reactive power management service.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1153-1155
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• 1997

Electric business all over the world is dramatically changed from vertically integrated monopoly to competition systems. Also, independent power producers(IPPs) will start their commercial operation from the year 2001 in Korea. In this regard, determination of the transaction cost between IPPs and electric utilities will be a hot issue, and electric utilities requires a new framework to support their decision-making. This paper presents the concept of the avoided cost which can be used for economic studies. This paper also describes a novel algorithm to evaluate the avoided cost of a IPP. The case studies are performed on the basis of the official generation expansion plan of Korea by using the Wien Automatic System Planning Package(WASP).