• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 A
• /
• pp.530-532
• /
• 2002

The contracted electric power and the demand factor of customers are used to predict the peak load in distribution transformers. The conventional demand factor was determined more than ten years ago. The contracted electric power and power demand have been increased. Therefore, we need to prepare the novel demand factor that appropriates at present. In this paper, we modify the demand factor to improve the peak load prediction of distribution transformers. To modify the demand factor, we utilize the 169 data acquisition devices for sample distribution transformers. The peak load currents were measured by the case studies using the actual load data, through which we verified that the proposed demand factors were correct than the conventional factors. A newly demand factor will be used to predict the peak load of distribution transformers.

• 상하수도학회지
• /
• 제28권4호
• /
• pp.377-389
• /
• 2014

In recent years, Smart Water Grid (SWG) concept has globally emerged over the last decade and also gained significant recognition in South Korea. Especially, there has been growing interest in water demand forecast and this has led to various studies regarding energy saving and improvement of water supply reliability. In this regard, this study aims to develop a nonlinear ensemble model for hourly water demand forecasting which allow us to estimate uncertainties across different model classes. The concepts was demonstrated through application to observed from water plant (A) in the South Korea. Various statistics (e.g. the efficiency coefficient, the correlation coefficient, the root mean square error, and a maximum error rate) were evaluated to investigate model efficiency. The ensemble based model with an cross-validate prediction procedure showed better predictability for water demand forecasting at different temporal resolutions. In particular, the performance of the ensemble model on hourly water demand data showed promising results against other individual prediction schemes.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2021년도 춘계학술대회
• /
• pp.35-37
• /
• 2021

외래 관광객 수요를 분석하고 예측하는 것은 관광 정책을 수립하고 기획하는데 지대한 영향을 미치기 때문에 관광 산업 분야에서 매우 중요하다. 외래 관광객 데이터는 여러 외적 요인들에 의해 영향을 받기 때문에, 시간에 따른 미세한 변화가 많다는 특징을 갖는다. 따라서, 최근에는 관광객 입국자 수요를 예측하기 위해 경제 변수 등 여러 외적 요인들도 함께 반영하여 예측 모델을 설계하는 연구를 진행하고 있다. 그러나 기존의 시계열 예측에 주로 사용되는 회귀분석 모델과 순환신경망 모델은 여러 변수들을 반영하는 시계열 예측에 있어 좋은 성능을 보이지 못했다. 따라서 우리는 합성곱 신경망을 활용하여 이러한 한계점들을 보완한 외래 관광객 수요 예측 모델을 소개한다. 본 논문에서는 한국관광공사에서 제공한 과거 10개년 외래 관광객 데이터와 추가적으로 수집한 여러 외적 요인들을 입력 변수로 반영하는 1차원 합성곱 신경망을 설계하여 외래 관광객 수요를 예측하는 모델을 제시한다.

• 인터넷정보학회논문지
• /
• 제21권5호
• /
• pp.39-48
• /
• 2020

Recently, the study and development of environment-friendly energy technique have increased in worldwide due to environmental pollution and energy resources problems. In vehicle industry, the development of electric vehicle(EV) is now on progress, and also, many other governments support the study and development and make an effort for EV to become widely available. In addition, though they strive to construct the EV infra such as a charge station for EV, the techniques related to managing charge demand and peak power are not enough. The standard of EV communication has been already established as ISO/IEC 15118, however, most of implemented EVs and EV charge stations do not support any communication between each of them. In this paper, an improved slow charge scheme for non-communication EVs is proposed and designed by using predicting charge demand. The proposed scheme consists of distributed charge model and charge demand prediction. The distributed charge model is designed to manage to distribute charge power depending on available charge power and charge demand. The charge demand prediction is designed to be used in the distributed charge model. The proposed scheme is based on the collected data which were from EV slow charge station in business building during the past 1 year. The system-level simulation results show that the waiting time of EV and the charge fee of the proposed scheme are better than those of the conventional scheme.

• 한국빅데이터학회지
• /
• 제1권1호
• /
• pp.9-17
• /
• 2016

본 연구에서는 상수관망에 설치된 유량, 압력 센서를 통해 취득한 빅데이터에 대해 데이터마이닝 기법을 활용하여 해당 공급권역의 특성을 파악하고 그 정보에 기반하여 상수 공급에 있어서 유의할 점 등을 도출해보고자 하였다. 또한, 상수 사용에 대한 단기 수요예측을 수행하는데 있어서도 통계적 방법인 다중회귀분석과 데이터마이닝의 인공신경망 기법을 비교하여 좀 더 정확한 수요예측을 할 수 있는 모델을 제시해보고자 하였다. 데이터 수집과 테스트를 위하여 지자체 한 군의 소블록 지역을 대상으로 선정하였다. 해당 지역은 가정용 수요 외에도 관공서, 병원 등의 대형 업무용 수요도 일부 존재하고 있는 지역이다. 해당 지역의 센서를 통해 취득되는 연속 발생 데이터를 수집하였다. 이런 방식을 통해 취득된 데이터는 총 2,728건이며 이 중 2,632건은 예측모델을 생성하는데 96건은 예측모델의 예측력을 테스트 하는 데에 활용하였다. 이러한 테스트를 수행한 결과 상수 수요예측에 있어서 인공신경망이 다중회귀분석에 비교하여 더 좋은 예측율을 보였다.

• KEPCO Journal on Electric Power and Energy
• /
• 제5권3호
• /
• pp.157-163
• /
• 2019

현재까지 피크완화 및 에너지 절감을 위해 한국전력공사 120여개 사옥에 K-BEMS (KEPCO Building Energy Management System)가 운영 중이다. 이 시스템은 PV, PCS, BESS, EMS 등으로 구성되어 있으며 건물에너지 수요예측을 기반으로 BESS, PV 등을 활용하여 에너지 관리를 도모하고 있다. 이 시스템은 단기 과거데이터에 신경망기법을 단순 적용하여 수요를 예측함에 따라 예측 정확도가 높지 않고 운영자 수작업을 통한 BESS 충방전으로 피크 저감이 곤란하며 운영 경제성 제고가 어려운 실정이다. 이러한 문제를 해결하기 위해 전력연구원에서는 2016년부터 3년간 연구과제를 수행하였는데 이를 통해 에러를 최소화하며 높은 신뢰도를 가지는 실시간 수요예측기법과 이에 기반한 BESS충방전 최적화 자동화 기술 개발, 성능을 검증하였기에 이를 본 논문에서 소개하고자 한다.

• Structural Engineering and Mechanics
• /
• 제54권4호
• /
• pp.741-754
• /
• 2015

This study evaluates prediction models for three EDPs (engineering demand parameters) using data from three symmetrical structures with RC walls designed according to the currently enforced Romanian seismic design code P100-1/2013. The three analyzed EDPs are: the maximum interstorey drift, the maximum top displacement and the maximum shear force at the base of the RC walls. The strong ground motions used in this study consist of three pairs of recordings from the Vrancea intermediate-depth earthquakes of 1977, 1986 and 1990, as well as two other pairs of recordings from significant earthquakes in Turkey and Greece (Erzincan and Aigion). The five pairs of recordings are rotated in a clockwise direction and the values of the EDPs are recorded. Finally, the relation between various IMs (intensity measures) of the strong ground motion records and the EDPs is studied and two prediction models for EDPs are also evaluated using the analysis of residuals.

• 한국항공운항학회지
• /
• 제26권4호
• /
• pp.101-109
• /
• 2018

In order to predict the future needs of the aircraft repair parts, each military group develops and applies various techniques to their characteristics. However, the aircraft and the equipped weapon systems are becoming increasingly advanced, and there is a problem in improving the hit rate by applying the existing demand prediction technique due to the change of the aircraft condition according to the long term operation of the aircraft. In this study, we propose a new prediction model based on the conventional time-series analysis technique to improve the prediction accuracy of aircraft repair parts by using machine learning model. And we show the most effective predictive method by demonstrating the change of hit rate based on actual data.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 B
• /
• pp.646-648
• /
• 1999

Kalman Filter model of demand for residental water and consumption pattern were tested for their ability to explain the hourly residental demand for water in metropolitan distribution system. The hourly residental demand for water is calculated from the daily residental demand and consumption pattern. The consumption pattern which has 24 time rates is characterized by data granulization in accordance with season kind, weather and holiday. The proposed approach is applied to water distribution system of metropolitan areas in Korea and its effectiveness is checked.

• 전기학회논문지
• /
• 제58권1호
• /
• pp.1-6
• /
• 2009

The traditional demand prediction was based on the technique wherein electric power corporations made monthly or seasonal estimation of electric power consumption for each area and subscription type for the next one or two years to consider both seasonally generated and local consumed amounts. Note, however, that techniques such as pricing, power generation plan, or sales strategy establishment were used by corporations without considering the production, comparison, and analysis techniques of the predicted consumption to enable efficient power consumption on the actual demand side. In this paper, to calculate the predicted value of electric power consumption on a short-term basis (15 minutes) according to the amount of electric power actually consumed for 15 minutes on the demand side, we performed comparison and analysis by applying a 15-minute interval prediction technique to the average and that to the time series analysis to show how they were made and what we obtained from the simulations.