Investigation on Application of Grey Cognate Analysis for Snowmelt Runoff Forecast
Lan Yongchao(Lanzhou Institute of Glaciology and Geoeryology, Academia Sinica)
Grey system Theory (GST) belongs to the category of System Theory. Grey means that the information is not complete. So Grey is a kind of system in which the information is not complete. Cognate Analysis is a measuring method which is used for judging the intimate degree of mutual relation between various factors in GST, that is this method is used for forming a whole comprison mechanism to get rid of the limitation of mutual comprison between various factors. It absorbs the measuring characteristic of distance space and whole comprison connotation of point topology space, and they are sublimated into grey cognatesapce, in which the weight and the sequence relation of each factor can be identified and determined respectively, the main behaviour in the system can also be divided. In this article,Grey Cognate Analysis was first applied for Judging the cognate degree between each affecting factor and snowmelt runoff in the upper Yellow River above the Longyang Gorge and determining the proper forecasters, which are used for developing the forecast model of the flow into the Longyang Gorge Reservoir, the largest reservoir on the Yellow River at present, during the spring snowmelt period (from March 20 to June 10).