OBJECTIVE The objective of this study was to compare the conversion degree of six different composite materials (Filtek Z 250, Filtek P60, Spectrum TPH, Pertac II, Clearfil AP-X, and Clearfil Photo Posterior) using three different light sources (blue light-emitting diode [LED], plasma arc curing [PAC], and conventional halogen lamp [QTH]). METHODS Composites were placed in a 2 mm thick and 5 ...

Reducing the number of components power electronic converters has been an important research topic over past few decades. This paper introduces a new structure for multi-level inverter based on reduced switch basic modules. The proposed module requires fewer switches and auxiliary devices. In addition, lesser on-state synthesis each voltage level results in less conduction losses, which enhance...

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Cascaded H-bridge multilevel power electronic converters generally require several dc sources. An alternative option is to replace all the separate dc sources feeding the H-bridge cells with capacitors, leaving only one H-bridge cell with a real dc voltage source. This will yield a cost-effective converter. However, the required capacitor voltage balancing is challenging. In this paper, using t...

The mechanism of differentiation with asymmetrical and symmetrical reinforcement was analysed on the basis of different impairments after medial and lateral prefrontal lesions. The medial prefrontal lesions impaired the retention of asymmetrical differentiation whereas the symmetrical differentiation was slightly or not impaired at all. The lateral prefrontal lesions impaired moderately the asy...

This paper presents the design and analysis and of the proposed zero voltage zero current switching (ZVZCS) full bridge dc-dc converter with transformer isolation and current doubler rectifier for high power and high performance by introducing ZVS for lagging leg and ZCS for leading leg operation It has a simple and robust structure with asymmetrical shifted pulse width modulation technique. Th...

For battery-powered electronic products, one way to extend battery life is to use a versatile step-up/step-down DC-DC converter. A new versatile step-up/step-down switched-capacitor-based converter structure is proposed, and its efficiency is analyzed. In the step-down case, the efficiency is the same as, or even better than the efficiency of linear regulators. key words: DC-DC converter, switc...