This thesis presents a resonant boost topology suitable for very high frequency (VHF, 30300 MHz) dc-dc power conversion. The proposed design is a fixed frequency, fixed duty ratio resonant converter featuring low device stress, high efficiency over a wide load range, and excellent transient performance. A 110 MHz, 23 W experimental converter has been built and evaluated. The input voltage range...

Recently, dynamic nuclear polarization enhanced nuclear magnetic resonance (DNP/NMR) has emerged as a powerful technique to obtain significant enhancements in spin spectra from biological samples. For DNP in modern NMR systems, a high power continuous-wave source in the submillimeter wavelength range is necessary. Gyrotrons can deliver tens of watts of CW power at submillimeter wavelengths and ...

T   he completed MCI includes three main channels of interest rate, exchange rate and credit rate. In developing countries such as Iran, this indicator, which contains a credit channel, could be better used to illustrate the country’s monetary condition. This study has been done to calculate this index for the period of 1978–2012. For this purpose, the function of the total economy demand ...

Two kinds of automata are introduced, for recognising regular and context-free nominal languages. We compare their expressive power with that of analogous proposals in the literature. Some properties of our languages are proved, in particular that emptiness of a context-free nominal language L is decidable, and that the intersection of L with a regular nominal language is still context-free. Th...

BACKGROUND Root extracts of Withania somnifera (Ashwagandha) are known to possess analgesic, anti-inflammatory and chondroprotective effects. An aqueous extract of roots plus leaves of this plant has shown to yield higher percentages of withanolide glycosides and, accordingly, may possess better analgesic, anti-inflammatory and chondroprotective effects than root alone extracts. OBJECTIVES To...

A complete procedure for the design of W-band low noise amplifier in MMIC technology is presented. The design is based on a simultaneously power and noise matched technique. For implementing the method, scalable bilateral transistor model parameters should be first extracted. The model is also used for transmission line utilized in the amplifier circuit. In the presented method, input/output ma...

unlike traditional power grids, smart grids have the advantage of bidirectional power flow and having distributed generations. distributed generation systems are usually supplied by renewable sources which can cause unpredicted voltage fluctuations as a result of being intermittent. while traditional compensating devices deal with the problem of voltage fluctuation and reduced power quality wit...

The recovery of bioactive products with green processes is a critical topic for the research and industry fields. In this work, application solid–liquid (SLE), microwave-assisted extraction (MAE) aq. ethanol 90% v/v supercritical fluid (SFE) CO2 biocomponents from Scenedesmus obliquus studied. effects examined were temperature (30–60 °C), time (6–24 h), solvent-to-biomass ratio (20–90 mLsolv/gb...

The double and triple Langmuir probe diagnostic systems with their necessary driving circuits are developed successfully for the characterization of laboratory built low pressure inductively coupled nitrogen plasma, generated by 13.56 MHz radio frequency (RF) power supply along with an automatic impedance matching network. Using the DC properties of these two probes, the discharge plasma parame...