This paper summarizes recently developed soft-switching inverters and proposes two alternative options for electric propulsion drives. The newly developed soft-switching inverter employs an auxiliary switch and a resonant inductor per phase to produce a zero voltage across the main switch so that the main switch can turn on at the zero-voltage condition. Both the auxiliary switch and the resona...

conclusions the study indicated advantages of this modified bier's block compared to the traditional one including ability to perform surgery on upper limb bones and considerable pain relief at surgical and tourniquet sites during the operation until one hour thereafter. results this study showed the presence of analgesia at surgical and tourniquet sites during the operation in 96% of patients,...

In recent years, a lot of research has been done in the field of producing soft magnetic nano composites by means of mechanical alloying. These materials indicate more electrical resistance and permeability in comparison with soft magnetic composites (SMCs). In this research, reduction of silicothermal mixed powder (Nickel-oxide, Silicon and Iron) was carried out by mechanical alloying to form ...

We demonstrate the generation of a highly polarized soft-x-ray beam with a compact high-repetition-rate tabletop soft-x-ray laser. The radiation emitted by a high-average-power discharge-pumped tabletop Ne-like Ar soft-x-ray laser operating at 46.9 nm was polarized with a pair of Si/Sc multilayer mirrors designed for 45° operation. A degree of polarization greater than 0.96 was obtained. The po...

A major problem in an isolated DC/DC converters operating at high switching frequencies is the attendant switching losses in the semiconductor devices. This can be reduced by introducing either zero-voltage switching (ZVS) or zero-current switching (ZCS) of the semiconductor switches. This paper deals with the simulation, design, fabrication and experimental evaluation of a novel soft-switching...

In this study, dynamic behavior of safety mechanism of a mechanical controller is investigated using 3D-FE simulation. This paper is concentrated on controller of a high acceleration projectile. The controller is located in the top of the projectile. Safety mechanism is divided to deformable and rigid parts. Deformable and rigid parts are simulated in Abaqus and Adams commercial soft wares; res...

Surgical intervention at the cervical spine bear a high risk of neurological deficits for the patient while the size of the operation field decrease, because of the trend towards minimal invasive surgery. Although conventional intraoperative imaging techniques, such as fluoroscopy have proven useful, they are limited in that they do not provide information continuously. Because of the intraoper...

A recent move by the UK government to purchase two new railway vehicle fleets from the provider offering the lowest whole-life, whole-system cost creates significant challenges to traditional manufacturers and their extended enterprises. This paper describes the work of a collaborative academic-industry research project; applying systems engineering to enable the optimisation of the operation a...