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Mamdani-type inference systems with trapezoidal-shaped fuzzy membership functions play a crucial role in a wide variety of engineering systems, including real-time control, transportation and logistics, network management, etc. The automatic identification or construction of such fuzzy systems input output data is one of the key problems in modeling. In the past years, the authors have investigated several different fuzzy t-norms, among others, algebraic and trigonometric ones, and the Hamacher product by substituting the standard 'min' t-norm operation, in order to achieve better model fitting. In the present paper, the focus is on examining the general parametric Hamacher t-norm, where the free parameter quite essentially influences the quality of modeling and the learning capability of the model identification system. Based on a wide scope of simulation experiments, a quasi-optimal interval for the value of the Hamacher operator is proposed. [ABSTRACT FROM AUTHOR]

Charging behaviour of MNOS structures containing Ge nanocrytals embedded at the SiO2/Si3N4 interface are studied by experiments and by calculating tunnelling probabilities of electrons and holes to the conductance or valence band of the nitride layer, respectively, for structures with and without nanocrystals. It is concluded that the optimal charging behaviour of MNOS structures without nanocrystals can be expected for an oxide thickness of 2-3 nm. The presence of semiconductor nanocrystals at the SiO2/Si3N4 interface enhances strongly the tunnelling probability of electrons and holes for structures with thin oxide layers (2-3 nm) at low electric fields, but they do not influence the charging behaviour of structures at high electric fields. The results of calculations are in agreement with the experimental results obtained on MNOS structures with Ge nanocrystals. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]