OBJECTIVES SPECT/slow-rotation low-output CT systems can produce streak artifacts in filtered backprojection (FBP) attenuation maps, impacting attenuation correction (AC) in myocardial perfusion imaging. This paper presents an adaptive Bayesian iterative transmission reconstruction (ABITR) algorithm for more accurate AC. METHODS In each iteration, ABITR calculated a three-dimensional prior co...

We propose a feasible waveguide design optimized for harnessing Stimulated Brillouin Scattering with long-lived phonons. The consists of fully suspended ridge surrounded by 1D phononic crystal that mitigates losses to the substrate while providing needed homogeneity build-up optomechanical interaction. coupling factor these structures was calculated be G B / Q m = 0.54 (W m) −1 intramodal backw...

By modeling synthetic Pn amplitudes in 2007, my colleagues and I proposed a Pn geometric-spreading model (Y2007) that takes into account the spherical shape of the Earth. In this study, we used a set of observed Pn amplitudes from the tectonically active regions of Asia to evaluate the performance of Y2007 and to develop new, observation-based Pn spreading models. Even though Y2007 provides imp...

We present and discuss the results of new multiple-scattering radiative transfer calculations for three representative types of galactic environments, filled with either homogeneous or two-phase clumpy dust distributions. Extinction and scattering properties for two types of interstellar dust, similar to those found in the average diffuse medium of the Milky Way Galaxy (MW) and the Bar of the S...

The enhancement of skin image in optical coherence tomography (OCT) imaging can help dermatologists to investigate tissue layers more accurately, hence the more efficient diagnosis. In this paper, we propose an image enhancement technique including speckle reduction, attenuation compensation and cleaning to improve the quality of OCT skin images. A weighted median filter is designed to reduce t...

We propose to use optical correlation to measure the quality of an optical link in real time, staying completely within the optical domain. We transmit a test signal of 010 and correlate the received (degraded) signal with 010. The strength and shape of the output measure dispersion and attenuation in just 3 bit periods (75 ps at 40 Gb/s) compared with minutes by traditional methods. Correlatio...

Bolted connections are widely used in the machine tool manufacturing and equipment. As it is well known, bolt preload will be attenuated by vibration of tools, which degenerate working life tools. In this paper, a new experimental design method introduced into study on attenuation: quadratic general rotary unitized design. The dynamic analysis bolted connection carried out based finely fragment...

In the flat panel detector-based cone beam CT system, the scatter photons which reach the flat panel detector increase the detected signal, produce the image cupping artifact and reduce the image contrast. To conquer the X-Ray scatter problem, this study proposes the beam attenuation grid -based scatter correction algorithm that needs to add a beam attenuation grid (BAG) between the X-Ray sourc...