In this paper a tool for synthetic generation of scanning laser radar data is described and its performance is evaluated. By analyzing data from the system, we will recognize objects on ground. In the measurement system it is possible to add several design parameters, which make it possible to test an estimation scheme under different types of system design. The measurement system model include...

The most commonly used polarimetric radar measurements in rainfall estimation are the reflectivity factor, usually at horizontal polarization (Zh), differential reflectivity (Zdr) and specific differential propagation phase (Kdp). Based on the above three measurements, a number of algorithms have been derived in the literature to estimate rainfall (see Bringi and Chandrasekar, 2001 for a summar...

introduction: attenuation correction is a useful process for improving myocardial perfusion spect and is dependent on activity and distribution of attenuation coefficients in the body (attenuation map). attenuation artifacts are a common problem in myocardial perfusion spect. the aim of this study was to compare the effect of attenuation correction using different attenuation maps and different...

Samples of concrete contain various waste materials, such as iron particulates, steel balls of used ball bearings and slags from steel industry were assessed for their anti-radiation attenuation coefficient properties. The attenuation measurements were performed using gamma spectrometer of NaI (Tl) detector. The utilized radiation sources comprised 137Cs and ⁶⁰Co radioactive elements with photo...

In this paper we describe and evaluate an image-based spectral CT method. Its central formula expresses measured CT data as a spectral integration of the spectral attenuation coefficient multiplied by a Local Weighting Function (LWF). The LWF represents the local energy weighting in the image domain, taking into account the system and reconstruction properties and the object self attenuation. A...

Broadband ultrasound attenuation (BUA) was measured at the calcaneum in 367 healthy white schoolchildren (193 girls and 174 boys) aged 6-15 years. The mean calcaneal BUA increased with age and was significantly related to age, height, and weight. Measurement of calcaneal BUA may be helpful in the radiation free assessment of childhood disorders associated with increased fracture risk.

The relationship between incident sound level and acoustic attenuation for four types of earplug and four types of earmuff have been investigated using freshly prepared and instrumented cadaver ears. Pure tones and 1/3-octave bands of random noise in the frequency range 125-8000 Hz were employed as steady-state stimuli with sound pressure levels between 75 and 125 dB. Impulses with peak sound l...

The measurement of the acoustic properties of highly attenuative materials such as bitumen is very difficult. One possibility is to use measurements of the extent to which filling a cylindrical waveguide with the material affects the dispersion relationship of the cylinder. Torsional modes have been excited using piezoelectric transducers placed at one end of the cylinder, while the phase veloc...

We report our experimental results of measurements of x-ray attenuation coefficients of aqueous solutions of a light absorbing dye, indocyanine green, and an immunoadjuvant, glycated chitosan. In the treatment of metastatic tumors in rats using a novel laser immunotherapy these solutions were administered in situ. The x-ray attenuation data of the solutions are essential to development of an x-...

The campaign to collect rain attenuation data on terrestrial links had commenced in Malaysian tropical climates for almost two decades. The terrestrial data so far collected have been greatly utilized to derive useful statistics for various microwave applications, such as frequency scaling, rain rate conversion factor, 1-min rain rate contour maps, wet antenna losses, and fade slope duration an...