• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.151-153
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• 2003

This paper was studied on using data of the protective relay by Power Quality Monitor. The protective relay will have problem to save data for PQM(Power Qualify Monitoring) analysis because the protective relay memory is limited. So this paper was proposed new data compression of the data was get from the protective relay. The scheme is compared each cycle after DFT(Discrete Fourier Transform). And scheme is verified through simulation of protective relay data was from real distribution system.

• Journal of Electrical Engineering and Technology
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• 제2권1호
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• pp.1-9
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• 2007

This paper presents the effects of an increase or a decrease of a power reserve by load flow calculations under the seasonal load patterns of each country for the future power shortages faced by the metropolitan areas or by the southeastern area of South Korea in North-East Asia. In this paper, the various cases of the power system interconnections in Far-East Asia are presented, and the resulting interconnected power systems are simulated by means of a power flow analysis performed with the PSS/E 28 version tool. Data for simulation were obtained from the 2-th long term plan of electricity supply and demand in KEPCO. The power flow map is drawn from simulated data and the comparative study is done. In the future, a power flow analysis will be considered to reflect the effects of seasonal power exchanges. And the plan of assumed scenarios will be considered with maximum or minimum power exchanges during summer or winter in North-East Asian countries.

• Journal of Radiation Protection and Research
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• 제26권3호
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• pp.215-224
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• 2001

In order to comply with revised national regulationson radiological protection and to implement recent nuclear data and dose conversion factors, KOPEC developed a new point kernel gamma and beta ray shielding analysis computer program. This new code, named VisualShield, adopted mass attenuation coefficient and buildup factors from recent ANSI/ANS standards and flux-to-dose conversion factors from the International Commission on Radiological Protection (ICRP) Publication 74 for estimation of effective/equivalent dose recommended in ICRP 60. VisualShieid utilizes graphical user interfaces and 3-D visualization of the geometric configuration for preparing input data sets and analyzing results, which leads users to error free processing with visual effects. Code validation and data analysis were performed by comparing the results of various calculations to the data outputs of previous programs such as MCNP 4B, ISOSHLD-II, QAD-CGGP, etc.

• 대한원격탐사학회지
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• 제37권1호
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• pp.97-110
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• 2021

Fog can cause large-scale human and economic damages, including traffic systems and agriculture. So, Korea Meteorological Administration is operating about 290 visibility meters to improve the observation level of fog. However, it is still insufficient to detect very localized fog. In this study, high-resolution grid-type visibility data were retrieved from irregularly distributed visibility data across the country. To this end, three objective analysis techniques (Inverse Distance Weighting (IDW), Ordinary Kriging (OK) and Universal Kriging (UK)) were used. To find the best method and parameters, sensitivity test was performed for the effective radius, power parameter and variogram model that affect the level of objective analysis. Also, the effect of data distribution characteristics (level of normality) on the performance level of objective analysis was evaluated. IDW showed a relatively high level of objective analysis in terms of bias, RMSE and correlation, and the performance is inversely proportional to the effective radius and power parameter. However, the two Krigings showed relatively low level of objective analysis, in particular, greatly weakened the variability of the variables, although the level of output was different depending on the variogram model used. As the level of objective analysis is greatly influenced by the distribution characteristics of data, power, and models used, care should be taken when selecting objective analysis techniques and parameters.

• 조명전기설비학회논문지
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• 제23권3호
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• pp.30-37
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• 2009

The majority of the causes for the failures of power transformers in operation are mechanical defects due to vibration. The vibration phenomenon was measured from the power transformers in operation in the substations. The vibration measurement was performed in a $6{\times}4$ structure on one side of each transformer. The vibrations of the measured points were presented in two and three dimensions and analyzed. The results, according to the elapsed year of the transformer and the load capacity to the transformer, were analyzed. These results could be used as basic data with which to establish vibration standards for power transformers. In addition, the load capacity-vibration phenomenon correlation was examined and regression analysis was performed to derive the estimation function. The vibration phenomenon according to the elapsed yeah was also estimated to derive the function. Then the analysis of the power transformers was used to set vibration standards for them based on the vibration data.

• 전기학회논문지
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• 제62권10호
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• pp.1361-1367
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• 2013

This paper describes and suggests the data visualization for real time power system operation based on energy management system. Because real time power system operation performs analysis of the vast amount of on-line data, the operators need intuitive data visualization to find out useful information in the big data. Especially, in emergency situation, the data visualization is able to assist the operators in handling the crisis quickly and efficiently. Therefore, this paper aims to improve displays of output of real time power system operation by visualizing on-line big data. Through this study, we can develop improved visualization technique for real time power system operation, which has highly readable displays of output and intuitive information.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권7호
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• pp.703-707
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• 2008

본 논문에서는 리눅스 기반 임베디드 시스템 상에서 하드웨어적으로 측정된 소모 전력 데이타를 기반으로 보다 효율적인 분석 기능을 제공하기 위한 소프트웨어 프로버를 설계하고 구현한다. 제안된 소프트웨어 프로버는 타겟 시스템에 모듈형태로 포함되어 전력 데이타를 수집하고, 하드웨어적으로 측정된 시간별 소모전력 데이타와의 동기화를 통하여 유저 어플리케이션 내의 유저 함수 흑은 커널함수 중에서 전력소모가 많은 부분을 찾는 기능을 제공한다. 또한, 구현된 소프트웨어 프로버의 유용성을 타겟 시스템 상에서 유저 어플리케이션 실행을 통하여 검증하였다.

• KIEE International Transactions on Power Engineering
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• 제4A권4호
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• pp.254-261
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• 2004

Traditionally, electrical power systems had formed the vertically integrated industry structures based on the economics of scale. However, power systems have been recently reformed to increase their energy efficiency. According to these trends, the Korean power industry underwent partial reorganization and competition in the generation market was initiated in 2001. In competitive electric markets, accurate load data is one of the most important issues to maintaining flexibility in the electric markets as well as reliability in the power systems. In practice, the measuring load data can be uncertain because of mechanical trouble, communication jamming, and other issues. To obtain reliable load data, an efficient evaluation technique to adjust the missing load data is required. This paper analyzes the load pattern of historical real data and then the tuned ARIMA (Autoregressive Integrated Moving Average), PCHIP (Piecewise Cubic Interpolation) and Branch & Bound method are applied to seek the missing parameters. The proposed method is tested under a variety of conditions and also tested against historical measured data from the Korea Energy Management Corporation (KEMCO).

• ETRI Journal
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• 제32권1호
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• pp.166-168
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• 2010

We investigate the possibility of using adiabatic logic as a countermeasure against differential power analysis (DPA) style attacks to make use of its energy efficiency. Like other dual-rail logics, adiabatic logic exhibits a current dependence on input data, which makes the system vulnerable to DPA. To resolve this issue, we propose a symmetric adiabatic logic in which the discharge paths are symmetric for data-independent parasitic capacitance, and the charges are shared between the output nodes and between the internal nodes, respectively, to prevent the circuit from depending on the previous input data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.275-277
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• 2003

This paper deals with Object-oriented Database(OODB) which is designed for power system analysis, and describes load flow analysis using OODB. Database management systems are widely used and achieve high reliability of data management in the engineering fields. However conventional database systems, relational database system, have disadvantages in application to power system analysis. This paper presents advantages of OODB for modeling complex data of a power system analysis. The OODB supports data modeling requirements of GUI applications and the performance is well acceptable for GUI applications.