In order to tailor dereverberation approaches to automatic speech recognition (ASR) systems, it is important to thoroughly understand the effect of reverberation on ASR performance. In this work, the effect is analyzed by varying the shape of the room impulse response (RIR) using two design parameters that are useful for defining the target response of typical dereverberation algorithms. The pa...

The ultrasound attenuation coefficient and dispersion from 0-70 MHz in whole human blood and its components (red blood cells and plasma) at 37°C is reported. The measurements are made using a fixed path substitution technique that exploits optical mechanisms for the generation and detection of ultrasound. This allows the measurements to cover a broad frequency range with a single source and rec...

The link between the spectral shape of the beam attenuation spectrum and the shape of the particle size distribution (PSD) of oceanic particles is revisited to evaluate the extent to which one can be predicted from the other. Assuming a hyperbolic (power-law) PSD, N(D) ? D(-xi), past studies have found for an infinite distribution of nonabsorbing spheres with a constant index of refraction that...

Recent research has demonstrated the value of polarimetric measurements for the correction of rain-path attenuation at X-band radar frequency and the estimation of rain parameters including drop-size distributions (DSD). The standard remotely-sensed precipitation products, from large operational Sor C-band network radars, have spatial resolutions that are often too coarse to reveal hydrological...

Transversely isotropic (TI) media with the frequency-independent quality-factor elements (also called “constant- Q” transverse isotropy) are often used to describe attenuation anisotropy in sedimentary rocks. The coefficients constant- Q TI models can be conveniently defined terms of Thomsen-type attenuation-anisotropy parameters. Recent research indicates that not all those parameters for such...

PURPOSE To evaluate the influence of the body mass index (BMI) on coronary artery opacification in 64-slice CT. MATERIAL AND METHODS Sixty-two patients retrospectively underwent ECG-gated 64-slice CT coronary angiography (tube potential 120 kV, tube current time product 650 mAs) after intravenous injection of 80 ml of iodinated contrast agent (320 mg/ml, 5 ml/s). Attenuation values (HU) were ...