background: patient radiation doses from computed tomography (ct) are increasing due to the number of ct examinations performed every day. the aim of this study was assess and evaluate patient radiation doses for adult’s common ct examinations to derive local diagnostic guidance levels for common ct examinations. materials and methods: volume and weighted computed tomography dose index (ctdivol...

Objective: To develop a CT elastography imaging system useful for part of the human body in which ultrasound is not capable of reaching. The proposed system would measure CT modality through fusion of the stiffness mapping on the images by the tactile sensor system, improving precision of the endoscopic operation. Methods: We made some liver fibrosis phantoms of bovine skin gelatin with various...

In this paper we define a new linearity measure which can be applied to open curve segments. The new measure ranges over the interval (0,1], and produces the value 1 if and only if the measured line is a perfect straight line segment. Also, the new linearity measure is invariant with respect to translations, rotations and scaling transformations.

Metal implants which saturate the CT number scale may require dosimetrist and physicist involvement to manually contour and assign an appropriate value to the metal for accurate dose calculation. This study investigated dose calculation based directly on extended CT scale images for different metals and geometries. The aim was to evaluate extended CT accuracy as a suitable alternative to standa...

BACKGROUND Variability in intracoronary computed tomography (CT) number may influence vessel quantification. We confirmed the feasibility of a novel method for measuring vessel diameter and area using coronary CT angiography (CCTA) with an optimized intracoronary CT number, 350 HU. METHODS We performed intravascular ultrasound (IVUS) imaging in 52 patients with significant stenosis detected b...

Most CT reconstruction system x-ray computed tomography (CT) is a well established visualization technique in medicine and nondestructive testing. However, since CT scanning requires sampling of radiographic projections from different viewing angles, common CT systems with mechanically moving parts are too slow for dynamic imaging, for instance of multiphase flows or live animals. A large numbe...

This paper is focused on a novel design of stepped diaphragm for MEMS capacitive pressure sensor used in tire pressure monitoring system. The structure of sensor diaphragm plays a key role for determining the sensitivity of the sensor and the non-linearity of the output.First the structures of two capacitive pressure sensors with clamped square flatdiaphragms, with different thicknesses are inv...

Using data taken during WFC3's Thermal Vacuum 2 (TV2) testing campaign, we have characterized the non-linearity of the IR-1 detector. Cubic polynomials were used to fit the signal and produce correction coefficients to remove the non-linearity effects. We have also created a mask that identifies pixels with non-nominal behavior. This population of pixels represents 4.1% of the total number of a...