in this paper, the operation of helix traveling wave tube in interaction region is investigated by using a three dimensional large signal lagrangian model in frequency domain. the complete simulation of these tubes is essential for optimum design and minimum manufacturing cost. this 3d code can compute interception current (or current losses ), beam radius changes in interaction region and the ...

The main feature of the Fast-Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) power supplies is to drive a controlled current fulfilling the requirements of this technique. This feature allows fast switching the current of the FFC magnet and performing accurate and repetitive current cycles. When designing this equipment the power losses is not a fundamental parameter of the optimization pr...

Power supply units (PSUs) with an equally shared load current are widely employed for data processing equipment like servers due to their advantages such as easy extension of power processing capability and simple thermal management. This paper presents a method to improve light-load efficiency by reducing load-independent losses such as capacitive turn-on and core losses and reduce the THD of ...

We examined the distress level of 102 Holocaust survivors in Israel during a recent period of continuous exposure of the Israeli population to terror and the threat of missile attack. Based on the Conservation of Resources (COR) theory, we explored the contribution of losses suffered during the Holocaust and of current loss of resources due to terror attacks on their distress level. Twenty one ...

Department of Electrical Power and Machines Faculty of Engineering Cairo University Giza, Egypt Abstract The quality of the current waveform generated by a current controlled, voltage source shunt active power filter depends basically on three factors: (i) The reference signal being generated; (ii) the modulation method used and (iii) the switching frequency of the PWM modulator. A new adaptiv...

The way in which electric power depends on the topology of circuits with mixed voltage and current sources is examined. The power flowing in any steady-state DC circuit is shown to depend on a minimal set of key variables called fundamental node voltages and fundamental edge currents. Every steady-state DC circuit can be decomposed into a voltage controlled subcircuit and a current controlled s...

overview Porcine epidemic diarrhoea virus (PEDv) was first recognized in the United Kingdom of Great Britain and Northern Ireland in 1971. Since then, PEDv has become endemic in many European and Asian countries, where PEDv infection typically results in minor outbreak incidents with relatively low mortality (Pan et al., 2012; Li et al., 2012b). In 2010, despite vaccination programmes, a virule...

The quality of the current waveform generated by a current controlled, voltage source shunt active power filter depends basically on three factors: (i) The reference signal being generated; (ii) the modulation method used and (iii) the switching frequency of the PWM modulator. A new adaptive hysteresis band modulation method is proposed. In this paper, the periodical sampling constant hysteresi...

Abstract This is the first of a series papers on novel methods for calculation eddy current losses in permanent magnets (PMs) and shortcomings previously conducted analyses. Eddy PMs their mitigation are significant factors when designing inverter-fed electric drives. Especially with need drives high power density, trend toward increased rotational speeds and, therefore, higher fundamental freq...

The assessment of crop yield losses is needed for the improvement of production systems that contribute to the incomes of rural families and food security worldwide. However, efforts to quantify yield losses and identify their causes are still limited, especially for perennial crops. Our objectives were to quantify primary yield losses (incurred in the current year of production) and secondary ...