A Synthetic Generation of Streamflows by ARMA(1, 1) Multiseason Model

ARMA(1, 1) 다계절모형에 의한 하천유량의 모의발생

The applicability of ARMA(1, 1) multiseason model, which is in the beginning stage of active researches in the field of synthetic generation is evaluated with the streamflow data at the Nakdong stage gauging station on the main stem of the Nakdong River. The method of parameter estimation for the modelis reviewed and the statistical analysis of the generated seasonal streamflows such as corrlogram analysis and the computation of moments is made. The results obtained by ARMA(1, 1) multiseason model are compared with the historical streamflow data and also with those by two other multiseason models, namely, Thomas-Fiering model and Matalas AR(1) multiseason model. The seasonal streamflows grnerated by three multiseason models were annually summed up to form respective annual flow series whose statistics were compared with those of the annual flow series generated by three annual models, namely, AR(1), Matalas AR(1), and ARMA(1, 1) annual models. The possibility of ARMA(1, 1) multiseason model for the simultaneous generation of seasonal and annual streamflows is also evaluated.

초기연구단계에 있는 ARMA(1, 1) 다계절모형에 의해 계절유량을 발생시키기 위한 모형의 변수결정방법과 유량발생 및 발생유량계열의 통계학적분석을 실시하였으며 타모형과의 비교를 위해 Thomas-Fiering 모형, Matalas AR(1) 다계절모형도 사용하였다. 다계절모형에 의해 발생시킨 계절유량을 연도별로 합산하여 얻은 연유량계열의 통계학적 특성치를 년모의발생모형에 의해 발생시킨 년유량계열의 통계특성치와 비교함으로써 ARMA(1, 1) 다계절모형에 의해 계절 및 년유량자료계열을 한꺼번에 모의발생시킬 수 있는 가능성을 평가하였다.