• Title/Summary/Keyword: linear recurrent formulae

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A Study of Short Term Forecasting of Daily Water Demand Using SSA (SSA를 이용한 일 단위 물수요량 단기 예측에 관한 연구)

  • Kwon, Hyun-Han;Moon, Young-Il
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.6
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    • pp.758-769
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    • 2004
  • The trends and seasonalities of most time series have a large variability. The result of the Singular Spectrum Analysis(SSA) processing is a decomposition of the time series into several components, which can often be identified as trends, seasonalities and other oscillatory series, or noise components. Generally, forecasting by the SSA method should be applied to time series governed (may be approximately) by linear recurrent formulae(LRF). This study examined forecasting ability of SSA-LRF model. These methods are applied to daily water demand data. These models indicate that most cases have good ability of forecasting to some extent by considering statistical and visual assessment, in particular forecasting validity shows good results during 15 days.

A Study of the Forecasting of Hydrologic Time Series Using Singular Spectrum Analysis (Singular Spectrum Analysis를 이용한 수문 시계열 예측에 관한 연구)

  • Kwon, Hyun-Han;Moon, Young-Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.2B
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    • pp.131-137
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    • 2006
  • We have investigated the properties of the Singular Spectrum Analysis (SSA) coupled with the Linear Recurrent Formula which made it possible to complement the parametric time series model. The SSA has been applied to extract the underlying properties of the principal component of hydrologic time series, which can often be identified as trends, seasonalities and other oscillatory series, or noise components. Generally, the prediction by the SSA method can be applied to hydrologic time series governed (may be approximately) by the linear recurrent formulae. This study has examined the forecasting ability of the SSA-LRF model. These methods were applied to monthly discharge and water surface level data. These models indicated that two of the time series have good abilities of forecasting, particularly showing promising results during the period of one year. Thus, the method presented in this study suggests a competitive methodology for the forecast of hydrologic time series.