Trends in the Development of Machinery and Associated Technology

ABSTRACT This paper shows the analysis of using different kernel function for development of optimal Support Vector Machine (SVM) model which could be applied for prediction of wear rate of casting parts. Development of SVM model is designed with the three kernel functions: Radial Basis Kernel Function (RBF), Exponential Radial Basis Kernel Function (ERBF) and Polynomial Kernel Function (POLY). For the development of Improved Support Vector Machine (ISVM) model mixture of kernels RBF+POLY from the real operating conditions. In order to select the optimal model the statistical indicators for all models are presented. Results show that the ISVM using ERBF+POLY mixed kernel function show the best results for the practical purposes. The proposed ISVM model with a mixture of kernels is able to accurately predict the wear rate of casting parts. Keywords: Support Vector Machine, Kernel functions, wear rate INTRODUCTION SVM is based on statistical learning theory and is a new achievement in the field of data-driven modelling and has been successfully implemented in classification, regression and function estimatio

Casting process optimization by the regression analysis applied on the wear resistant parts molding

Provodeći sveobuhvatno istraživanje procesa lijevanja dijelova otpornih na habanje (lijevanje bijelog željeza), uspostavljena je značajna korelacija između tehnoloških parametara (temperatura, vrijeme starenja u kalupu i protok rashladnog sredstva) i tvrdoće finalnog proizvoda. Osnovna teorija Box-Wilsonove metode gradijenta činila je osnovu za predviđena istraživanja. Ta metoda definira koherentnost parametara procesa budući da je njihova disperzija u ispitivanom procesu relativno mala. Glavni je cilj eksperimenta bila definicija optimalnih uvjeta lijevanja. Stoga su identificirane različite tehnološke rute i modifikacije u procesu lijevanja dok se nije postigao najbolji rezultat. Ciljna je funkcija u početku imala oblik hipoteze, ali je kasnije dobila konzistentan oblik primjenom statističkih podataka dobivenih eksperimentom, optimizacijom procesa i upravljanjem procesom na bazi empirijske povratne veze.Conducting a comprehensive research of the casting process of wear resistant parts (white hard casting), a significant correlation is established between the technological parameters (temperature, aging time in the mold and coolant flow) and the final product hardness. The fundamental theory of Box-Wilson\u27s gradient method marked the baseline for the foreseen researches. The method defines the coherence of the process parameters, since their dispersion in the examined process is relatively small. Main target of the experiment was a definition of the optimal casting conditions. Therefore the different technological routes are identified and the casting process is modified until the best outcome is achieved. Target function was initially in a hypothesized form, while later on evolved into a consistent form due to the application of experiment-statistics, process optimization and process management based on empirical feedback