• Title/Summary/Keyword: Forecasting accuracy

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Development of a Runoff Forecasting Model Using Artificial Intelligence (인공지능기법을 이용한 홍수량 선행예측 모형의 개발)

  • Lim Kee-Seok;Heo Chang-Hwan
    • Journal of Environmental Science International
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    • v.15 no.2
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    • pp.141-155
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    • 2006
  • This study is aimed at the development of a runoff forecasting model to solve the uncertainties occurring in the process of rainfall-runoff modeling and improve the modeling accuracy of the stream runoff forecasting, The study area is the downstream of Naeseung-chun. Therefore, time-dependent data was obtained from the Wolpo water level gauging station. 11 and 2 out of total 13 flood events were selected for the training and testing set of model. The model performance was improved as the measuring time interval$(T_m)$ was smaller than the sampling time interval$(T_s)$. The Neuro-Fuzzy(NF) and TANK models can give more accurate runoff forecasts up to 4 hours ahead than the Feed Forward Multilayer Neural Network(FFNN) model in standard above the Determination coefficient$(R^2)$ 0.7.

Farming Expert System using intelligent (지능을 이용한 농사 전문가 시스템)

  • Hong You-Sik
    • Journal of the Korea Computer Industry Society
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    • v.6 no.2
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    • pp.241-248
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    • 2005
  • Conventional estimating methods forecast the future that it usually using the past statistical numerical value. In order to forecast the farming price, it must need many effort and accuracy knowledge. Therefore, to solve the these problems, this paper to improve forecasting farming price using fuzzy rules and neural network as a preprocessing. Also, we developed an intelligent farming expert system for real time forecasting as a postprocessing about unexpectable conditions. Computer simulation results proved reducing pricing error which proposed farming price expecting system better than conventional demand forecasting system does not using fuzzy rules.

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An Innovative Application Method of Monthly Load Forecasting for Smart IEDs

  • Choi, Myeon-Song;Xiang, Ling;Lee, Seung-Jae;Kim, Tae-Wan
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.984-990
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    • 2013
  • This paper develops a new Intelligent Electronic Device (IED), and then presents an application method of a monthly load forecasting algorithm on the smart IEDs. A Multiple Linear Regression (MLR) model implemented with Recursive Least Square (RLS) estimation is established in the algorithm. Case Study proves the accuracy and reliability of this algorithm and demonstrates the practical meanings through designed screens. The application method shows the general way to make use of IED's smart characteristics and thereby reveals a broad prospect of smart function realization in application.

Real Time Flood Forecasting Using Artificial Neural Networks (인공신경망 이론을 이용한 실시간 홍수량 예측 및 해석)

  • Kang, Moon-Seong;Park, Seung-Woo
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2002.10a
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    • pp.277-280
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    • 2002
  • An artificial neural network model was developed to analyze and forecast real time river runoff from the Naju watershed, in Korea. Model forecasts are very accurate (i.e., relative error is less than 3% and $R^2$ is great than 0.99) for calibration data sets. Increasing the time horizon for validation data sets, thus making the model suitable for flood forecasting, decreases the accuracy of the model. The resulting optimal EBPN models for forecasting real time runoff consists of ten rainfall and four and ten runoff data (ANN0410 and ANN1010 models). Performances of the ANN0410 and ANN1010 models remain satisfactory up to 6 hours (i.e., $R^2$ is great than 0.92).

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한국과 미국간 항공기 탑승객 수 예측을 위한 뉴럴네트웍의 응용

  • 남경두
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1995.09a
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    • pp.334-343
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    • 1995
  • In recent years, neural networks have been developed as an alternative to traditional statistical techniques. In this study, a neural network model was compared to traditional forecasting models in terms of their capabilities to forecast passenger traffic for flights between U.S. and Korea. The results show that the forecasting ability of the neural networks was superior to the traditional models. In terms of accuracy, the performance of the neural networks was quite encouraging. Using mean absolute deviation, the neural network performed best. The new technique is easy to learn and apply with commercial neural network software. Therefore, airline decision makers should benefit from using neural networks in forecasting passenger loads.

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Short-Term Load Forecasting of Pole-Transformer Using Artificial Neural Networks (신경회로망을 이용한 배전용 변압기의 단기부하예측)

  • Kim, Byoung-Su;Shin, Ho-Sung;Song, Kyung-Bin;Park, Jung-Do
    • Proceedings of the KIEE Conference
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    • 2005.07a
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    • pp.810-812
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    • 2005
  • In this paper, the short-term load forecasting of pole-transformer is performed by artificial neural networks. Input parameters of the Nosed algorithm are peak loads of pole-transformer of previous days and their temperatures. The proposed algorithm is tested for ore of the pole-transformers in seoul, korea. Test results show that the proposed algorithm improves the accuracy of the load forecasting of pole-transformer compared with the conventional algorithm.

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Forecasting uranium prices: Some empirical results

  • Pedregal, Diego J.
    • Nuclear Engineering and Technology
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    • v.52 no.6
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    • pp.1334-1339
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    • 2020
  • This paper presents an empirical and comprehensive forecasting analysis of the uranium price. Prices are generally difficult to forecast, and the uranium price is not an exception because it is affected by many external factors, apart from imbalances between demand and supply. Therefore, a systematic analysis of multiple forecasting methods and combinations of them along repeated forecast origins is a way of discerning which method is most suitable. Results suggest that i) some sophisticated methods do not improve upon the Naïve's (horizontal) forecast and ii) Unobserved Components methods are the most powerful, although the gain in accuracy is not big. These two facts together imply that uranium prices are undoubtedly subject to many uncertainties.

A Study on Estimation of Wind Power Generation using Weather Data in Jeju Island (기상관측자료를 이용한 제주도 풍력단지의 풍력발전량 예측에 관한 연구)

  • Ryu, Goo-Hyun;Kim, Ki-Su;Kim, Jae-Chul;Song, Kyung-Bin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.12
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    • pp.2349-2353
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    • 2009
  • Due to high oil price and global warming of the earth, investments for renewable energy have been increased a lot continuously. Specially, wind power has been received a great attention in the world. In order to construct a new wind farm, forecasting of wind power generation is essential for a feasibility test. This paper investigates wind velocity measurement data of Gosan weather station which located in Hankyung of Jeju island. This paper presents results of estimation of wind power generation using digital weather forecast provided from Korea meteorological administration, and the accuracy of the wind power forecasting by comparison between forecasted data and actual wind power data.

Error Forecasting Using Linear Regression Model

  • Ler, Lian Guey;Kim, Byung-Sik;Choi, Gye-Woon;Kang, Byung-Hwa;Kwang, Jung-Jae
    • Journal of Wetlands Research
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    • v.13 no.1
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    • pp.13-23
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    • 2011
  • In this study, Mike11 will be used as the numerical model where a data assimilation method will be applied to it. This paper aims to gain an insight and understanding of data assimilation in flood forecasting models. It will start with a general discussion of data assimilation, followed by a description of the methodology and discussion of the statistical error forecast model used, which in this case is the linear regression. This error forecast model is applied to the water level forecast simulated by MIKE11 to produced improved forecast and validated against real measurements. It is found that there exists a phase error in the improved forecasts. Hence, 2 general formula are used to account for this phase error and they have shown improvement to the accuracy of the forecasts, where one improved the immediate forecast of up to 5 hours while the other improved the estimation of the peak discharge.

Supramax Bulk Carrier Market Forecasting with Technical Indicators and Neural Networks

  • Lim, Sang-Seop;Yun, Hee-Sung
    • Journal of Navigation and Port Research
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    • v.42 no.5
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    • pp.341-346
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    • 2018
  • Supramax bulk carriers cover a wide range of ocean transportation requirements, from major to minor bulk cargoes. Market forecasting for this segment has posed a challenge to researchers, due to complexity involved, on the demand side of the forecasting model. This paper addresses this issue by using technical indicators as input features, instead of complicated supply-demand variables. Artificial neural networks (ANN), one of the most popular machine-learning tools, were used to replace classical time-series models. Results revealed that ANN outperformed the benchmark binomial logistic regression model, and predicted direction of the spot market with more than 70% accuracy. Results obtained in this paper, can enable chartering desks to make better short-term chartering decisions.