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The use of permanent magnet-assisted synchronous reluctance motor (PMA-SynRM) is increasing due to its advantages and superiority over induction motors. The undesirable effects of the encoder measurement error on the drive systems especially during low-range speeds may cause disorder in drive performance and sometimes its instability. For the low-cost application that requires a low-resolution encoder, this problem is felt obviously. This article presents a mathematical solution in order to compensate for the instability problem of a PMA-SynRM control at low speeds based on an augmented state unscented Kalman filter (ASUKF). First, a mathematical analysis for the effect of encoder error on the speed control instability is performed, and then an augmented nonlinear dynamical model for the PMA-SynRM is derived. Using an ASUKF on the presented augmented model of the PMA-SynRM, the error of the encoder is detected and accurately estimated. Using the estimated errors and pure motor state variables, the accuracy and robustness of the control are increased and its stability is guaranteed. The experiments performed for a 0.35 kW PMA-SynRM confirm the performance validity of the proposed method. [ABSTRACT FROM AUTHOR]

Background: The use of DOX as an anticancer agent is associated with serious side effects on normal cells especially in cardiovascular tissue., Objective: Here, it is proposed that the combination of a low dose of DOX with AgNPs provides ideal cytotoxicity against cancer cells and decreases side effects on normal human cells. This study evaluates the cytotoxic effects of green-synthetized AgNPs (GS-AgNPs) in combination with DOX in cancerous cells (MCF7) and investigates its influences on cell growth and apoptosis in a normal cell line of the heart (H9c2)., Methods: We used coffee extracts, as a reducing and stabilizing agent for the green-synthesis of AgNPs. GSAgNPs were characterized by using various analytical methods. MTT assay was used for cell toxicity analysis in cancerous and normal cells. Moreover, Annexin-V /PI staining and mRNA expression of Bax, Bcl2 and p53 were performed for apoptosis measurement in heart normal cell line., Results: GS-AgNPs showed more biocompatibility for normal cells and higher cytotoxicity for cancerous cells compared to that reported for chemically synthesized nanoparticles. Our results also demonstrated that a selected combination of DOX and AgNPs, 20 μM AgNPs / 0.3 μM DOX, had a suitable cytotoxic effect against cancerous cells with a minimum toxic effect on normal cells. So, no significant alteration was observed in cell migration capacity, apoptosis and gene expression of BAX, Bcl-2 and P53 when H9c2 cells were treated with 20 μM AgNPs / 0.3 μM DOX relative to the non-treated control., Conclusion: Finally, it seems that the combination of GS-AgNPs and DOX could be a potent strategy to combat cancer., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)