Consider a four-quadrant detector consisting of four circular active regions of area Aq each, placed symmetrically around the sample, as shown schematically in Fig. 1(a). The sample holder is inserted from the right, and the quadrants are 90° apart, oriented symmetrically at ±45° with respect to the primary tilt axis. The specimen tilt angles are labeled  and β, with positive angles correspond...

When in vivo proton dosimetry is performed with a metal-oxide semiconductor field-effect transistor (MOSFET) detector, the response of the detector depends strongly on the linear energy transfer. The present study reports a practical method to correct the MOSFET response for linear energy transfer dependence by using a simplified Monte Carlo dose calculation method (SMC). A depth-output curve f...

The CZT detector on the InFOCμS hard X-ray telescope is a pixellated solid-state device capable of imaging spectroscopy by measuring the position and energy of each incoming photon. The detector sits at the focal point of an 8m focal length multilayered grazing incidence X-ray mirror which has significant effective area between 20–40 keV. The detector has an energy resolution of 4.0 keV at 32 k...

In this paper we justify the need and describe the implementation of a spectral coherence based double-talk detector for line echo cancelers on a 16 bit signal processor. We address specific fixed-point implementation issues and we illustrate the superiority of the solution over the energy/level based Geigel detector, along with a discussion about the use cases.

The aim of this study is the development of a methodology to reconstruct the image of detail defects from a mammographic phantom employed in quality control testing. The MCNP-4c2 code has been used to model the mammography unit and the CIRS 11A (MAMMO PHANTOM SP01) mammographic phantom. This phantom is made of poly-methyl methacrilate and contains a reference point, contrast and resolution deta...

This paper proposes the virtual flux based direct power control for Vienna rectifier. No need for the input voltage sensors, the current regulation loop and PWM voltage modulation block along with the active and reactive power decoupling are some of the salient advantages of this method that make it suitable for controlling the conventional active rectifiers. However, due to the three-level nat...

PURPOSE To compare in an animal model the image quality of multiplanar reformation and three-dimensional (3D) reconstruction images of the central airways by using single-detector row computed tomography (CT) and multi-detector row CT at varied tube currents and to compare radiation dose. MATERIALS AND METHODS Five dogs each underwent five consecutive helical CT examinations (one single-detec...

phase sensitive detector described here has two principal applications: a- to produce a d.c out put proportional to- the amplitude of an incoming a,c signal and indicate, by the outut polarity, the phase of the signal with respect to an internal reference. b- to detect the presence of a signal of known phase and frequency which would otherwise be lost in «background noise» and to measure its am...