A note of hybrid GR-SVM for prediction of surface roughness in abrasive water jet machining

The paper attempts at reviewing a previous research entitled “Hybrid GR-SVM for prediction of surface roughness in abrasive water jet (AWJ) machining” and some problems were found in its reducing parameters process and prediction model. The authors presented a hybrid of grey relation analysis (GRA) and support vector machine (SVM) to estimate the roughness surface in a certain dataset of AWJ machining. Their proposed method may not work in real case of AWJ machining as it is claimed. This paper gives a counter model in order to illustrate these remarks.