Results 201 to 210 of about 230,662 (251)
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Signal-to-noise ratio improvement in photoacoustic imaging
2020Halbleiterdiodenlaser ermöglichen für die photoakustische Bildgebung kostengünstige, kompakte und gut integrierte Aufbauten, die jedoch unter geringem Rauschabstand leiden. Zwei Möglichkeiten zur Verbesserung des Rauschabstandes wurden untersucht.
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Radiology, 1988
The efficiency and quality of three-dimensional Fourier transform (3DFT) magnetic resonance imaging were evaluated and compared with those of 2DFT imaging. For a fixed imaging time and number of sections, 3DFT imaging with conventional spin echoes always
J. Carlson +4 more
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The efficiency and quality of three-dimensional Fourier transform (3DFT) magnetic resonance imaging were evaluated and compared with those of 2DFT imaging. For a fixed imaging time and number of sections, 3DFT imaging with conventional spin echoes always
J. Carlson +4 more
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High resolution and high signal-to-noise ratio imaging with near-field high-order optical signals
Nano Reseach, 2022Fei Wang +5 more
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Ultimate signal-to-noise-ratio of surface and body antennas for magnetic resonance imaging
, 2000Approximating the human body by a homogeneous half-space or cylinder the electromagnetic fields of surface antennas or wholebody antennas for magnetic resonance imaging (MRI) can analytically be calculated.
W. Schnell +3 more
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Medical Physics (Lancaster), 2005
In hyperpolarized noble gas (HNG) magnetic resonance (MR) imaging, the available polarization is independent of magnetic field strength and for large radiofrequency (rf) coils, such as those used for chest imaging, the body noise becomes the primary ...
J. Parra-Robles, A. Cross, G. Santyr
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In hyperpolarized noble gas (HNG) magnetic resonance (MR) imaging, the available polarization is independent of magnetic field strength and for large radiofrequency (rf) coils, such as those used for chest imaging, the body noise becomes the primary ...
J. Parra-Robles, A. Cross, G. Santyr
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Contrast signal-to-noise ratio for image quality assessment
IEEE International Conference on Image Processing 2005, 2005Peak signal-to-noise ratio (PSNR) is commonly used as an objective quality metric in signal processing. However, PSNR correlates poorly with the subjective quality rating. In this paper, we propose a new metric using contrast signal-to-noise ratio (CSNR), which measures the ratio of the contrast information level of distorted signal to the contrast ...
Zhongkang Lu +3 more
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Coded penumbral imaging for improvements of signal-to-noise ratio
Review of Scientific Instruments, 2004Penumbral imaging is a power imaging technique for radiations with long mean-free path. Since the reconstruction is based on deconvolution, the technique is sensitive to noise contained in penumbral images. In this article, we proposed a uniformly redundant penumbral array (URPA) technique to improve the signal-to-noise (SN) ratio of penumbral images ...
Hiroki Yamamoto +2 more
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Improvement of the signal-to-noise ratio in the acquisition of photoplethysmographic images
SPIE Proceedings, 2012In this work we report the improvement of signal-to-noise ratio in photoplethysmographic images by using a linear polarized filtered light source and the capture of the corresponding scene through a linear polarized analyzer; we also discuss the impact of its use in non-contact reflection photoplethysmographic setups.
Marija Strojnik +2 more
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Imaging through turbulence: Degradation of signal-to-noise ratio
Optics Communications, 1984Abstract In this paper, we formulate the signal-to-noise ratio (SNR) of a direct-detection imaging system in turbulent media. From the formulation, we find that the SNR varies in the image plane and that the object radiation pattern affects SNR dramatically. An example is given to demonstrate the turbulence effect on the degradation of SNR.
Martin A Plonus, S. J. Wang
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Maximizing signal-to-noise and contrast-to-noise ratios in flash imaging
Magnetic Resonance Imaging, 1987This paper presents an analysis of signal-to-noise and contrast-to-noise ratios from small tip angle, gradient reversal (FLASH) imaging. Analytic and numerical techniques are used to determine the delay times and tip angles that maximize signal-to-noise per unit time from a single tissue. Similar procedures are used to determine the delay times and tip
J. Bruce Kneeland +2 more
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