a new output structure for class e power amplifier (pa) is proposed in this paper. a series lc resonator circuit, tuned near the second harmonic of the operating frequency is added to the output circuit. this resonator causes low impedance at the second harmonic. the output circuit is designed to shape the switch voltage of the class e amplifier and lower the voltage stress of the transistor. t...

We evaluated friction fatigue-induced changes in the microstructure and residual stress of carburized steel. By eddy current testing (ET) x-ray diffractometry (XRD), voltage rate (after/before fatigue testing) obtained by ET had a strong correlation with retained austenite phase full width at half maximum XRD. The results are useful for analysis damage

Vibrations of a fixed–fixed narrow microbeam electrostatically actuated by applying a voltage difference to it and a parallel rigid conductor are analyzed. For gaps between the two conductors that are comparable to the beam’s thickness, the fundamental frequency of the beam may first increase with increasing applied voltage, before suddenly dropping at the pull-in voltage. Available models fail...

Random energisation of power transformers often causes significant inrush currents and steep switching voltage wave fronts that are responsible for several adverse effects like huge current forces in the transformer windings, dielectric stress of the transformer winding insulation and temporary overvoltages. Controlled switching taking into account the residual flux is able to eliminate these i...

purpose: to evaluate residual refractive errors after cataract surgery and its determinant factors at farabi eye hospital, tehran. methods: simple random sampling was done among cataract surgery scheduled patients over a 4 year period (2003-2006). exclusion criteria were uveitis, previous intraocular surgery and ocular trauma. after applying the exclusion criteria, 423 patients were studied. le...

background: induction chemotherapy for acute lymphoblastic leukemia achieves complete remis sion in over 90% of children. it is apparent therefore that many patients in clinical remission and with out residual disease detectable by conventional light microscopy of peripheral blood or bone marrow films still harbor viable cells of the original disease mrd analysis does have a useful role to play...

The implementation of each function a battery management system (BMS) depends on sensor data. Efficient fault diagnosis is essential to the durability and safety systems. In this paper, model-based scheme fault-tolerant control strategy for voltage current are proposed with recursive least-square (RLS) unscented Kalman filter (UKF) algorithms. uses an open-circuit residual generator capacity ge...

The technically pure copper is being replaced by aluminium as conductive material in electrical transformers for power systems. This evolution brings new manufacturing challenges. One major difficulty is the limited weld ability and non-acceptable residual deformations of the aluminium, when welded by fusion arc welding processes. The Friction Stir Welding (FSW) was selected for evaluation cons...

this paper presents a control strategy for fuel cell/energy storage power generation system during voltage sag conditions. the hybrid dc power sources are connected to grid using power electronic converters include dc-dc converter and grid connected voltage source inverter. the power from hybrid power sources is controlled during voltage sag by designing of control strategy for dc-dc converter....

Research on the secondary arc has long been important in development of ultrahigh-voltage (UHV) transmission technology. Predicting arcing time is for single-phase automatic reclosing circuit breaker to protect power system. In response this problem, study uses a multifactor variance model select factors that significantly influence and verifies its validity through residual analysis. The resul...