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The Generalized Contrast-to-Noise Ratio
2018 IEEE International Ultrasonics Symposium (IUS), 2018Many adaptive algorithms claim to provide higher contrast than delay-and-sum (DAS). These claims are often backed by estimations of the contrast-to-noise ratio (CNR). Intuitively, we assume that higher CNR leads to higher probability of lesion detection, and this is indeed the case for DAS.
Alfonso Rodriguez-Molares +5 more
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Contrast ratios of polymer-dispersed liquid crystal films
Applied Optics, 1987Contrast ratio is an important measure of the performance of an electrooptic display. From measurements of film brightness and transmittance, we determined contrast ratios of thin polymer films containing microdroplets of liquid crystalline material. Contrast ratios based on brightness were typically ~3 for all samples studied, whereas contrast ratios ...
G P, Montgomery, N A, Vaz
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Improved contrast to tissue ratio at higher harmonics
Ultrasonics, 2002The challenge in ultrasound contrast imaging is a better discrimination between the perfused tissue and the contrast bubbles, which is usually expressed by contrast to tissue ratio (CTR). Imaging based on the second harmonic frequency showed a higher CTR than imaging at the fundamental frequency.
Bouakaz, A +3 more
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Contrast Ratio of Six Zirconia‐Based Dental Ceramics
Journal of Prosthodontics, 2014AbstractPurposeThe objective of this study was to determine the effect of thickness and brands on the contrast ratio of six zirconia dental ceramics.Materials and MethodsSix brands of yttria‐stabilized tetragonal zirconia polycrystalline (Y‐TZP) ceramics (ZENO® Translucent, Lava™ Plus High Translucency, inCoris TZI, Cercon® Base, Zeno®Zr, Lava™) were ...
Widchaya, Kanchanavasita +4 more
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An analysis of elastographic contrast-to-noise ratio
Ultrasound in Medicine & Biology, 1998We present a theoretical formalism and simulation results that allow the incorporation of the elastic contrast properties of tissues with simple geometries into the elastographic noise models developed previously. This analysis results in the computation of the elastographic contrast-to-noise ratio (CNRe).
T, Varghese, J, Ophir
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Contrast and Signal-to-Noise Ratio
1996In an MR image, information is contained in the variation across the image of one single parameter: the grey level, which is a proportional to the signal level at that position. This parameter, called contrast, is the result of three properties of the imaged tissue: the proton density, p; the spin-lattice relaxation time, T 1; and the spin-spin ...
Marinus T. Vlaardingerbroek +1 more
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Contrast-to-noise ratio optimization for a prototype phase-contrast computed tomography scanner
Review of Scientific Instruments, 2015In the field of biomedical X-ray imaging, novel techniques, such as phase-contrast and dark-field imaging, have the potential to enhance the contrast and provide complementary structural information about a specimen. In this paper, a first prototype of a preclinical X-ray phase-contrast CT scanner based on a Talbot-Lau interferometer is characterized ...
Mark Müller +8 more
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Content-aware contrast ratio measure for images
Signal Processing: Image Communication, 2018Abstract In image fidelity assessment it is often necessary to quantify the level of visibility between a structure of interest or foreground and its surrounding background, i.e., the contrast ratio. Today, there is no standard procedure to measure the contrast ratio in digital images.
B. Ortiz-Jaramillo +3 more
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Orthogonal Contrasts in Slope Ratio Investigations
Biometrics, 1959It is customary in the analysis of variance of balanced experimenlts to partition sums of squares into nmean squares corresponding with linear, quadratic, and other components of regression of response on the various independent variables. Undoubtedly this is a reasonable approach if the overall fornm of the regression line is the object of study, but ...
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1000:1 Contrast Ratio Transmissive Electrowetting Displays
Journal of Display Technology, 2011Transmissive electrowetting display pixels are reported with ~1000:1 contrast ratio and >; 50% optical transmission. This high performance is enabled by improved optical density of a black oil layer, and through use of an integrated metal reflector.
A. Schultz +3 more
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