In the paper, results on theoretical and experimental stability analysis of a milling process for small radial immersion and corresponding chatter phenomena are presented. Besides the known instability that resembles Hopf bifurcation and causes the onset of quasi-periodic chatter, a new instability resembling flip bifurcation that causes onset of periodic chatter with a 2T period has been observed, numerically and experimentally. In the stability diagram, the periodic chatter lobes are closed curves distributed within the stability region.
COBISS.SI-ID: 8345627
A method for non-destructive machine fault detection based on the evaluation of acoustic machine signatures is proposed. For the purpose of machine fault detection, a gamma-tone filter bank is applied in the pre-processing of acoustic signals and features are then extracted to represent the machine signature. The proposed approach is illustrated by a case study where the quality of commercially produced compressors is estimated. Results show that major faults which occur in production can be reliably detected.
COBISS.SI-ID: 9744923
In the paper, a phenomenological description of a novel method for laser droplet formation from a metal wire is presented. A method for and consideration of the LDF process in two phases is proposed: formation of a pendant droplet and droplet detachment. Based on the heat and force balance, parameters of the laser pulse and wire-feeding parameters for the LDF process have been estimated, and have been experimentally verified.
COBISS.SI-ID: 8981275
Efficient operation of modern energy distribution systems often requires the forecasting of future energy demand. This paper proposes a strategy to estimate forecasting risk. The strategy combines an energy demand forecasting model, an economic incentive model and a risk model. Based on the forecasting model and the economic model, the development of a risk model is proposed. The risk model is applicable to estimating the daily forecasting risk based on the influencing parameters. The proposed approach is illustrated by a case study of a Slovenian natural gas distribution company.
COBISS.SI-ID: 10005531
Efficient control of a machining process requires the reliable prediction of process behaviour. In this article, a prediction method based on statistical modelling of fields was introduced. The method was applied to a laser welding process, where the quality of weld depends strongly on welding parameters. Comparison of the predicted field distributions with testing field distributions revealed an excellent correspondence between the two patterns.
COBISS.SI-ID: 10007835