Results 221 to 230 of about 406,491 (258)

Accuracy of approximate inversion schemes in quantitative photoacoustic imaging

SPIE Proceedings, 2014
Five numerical phantoms were developed to investigate the accuracy of approximate inversion schemes in the reconstruction of oxygen saturation in photoacoustic imaging. In particular, two types of inversion are considered: Type I, an inversion that assumes fluence is unchanged between illumination wavelengths, and Type II, a method that assumes known ...
Roman Hochuli, Paul C. Beard, Ben Cox
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Detection accuracy of in vitro approximal caries by cone beam computed tomography images

European Journal of Radiology, 2011
To evaluate the diagnostic accuracy of approximal carious lesions among five CBCT systems and to assess the effect of detector types employed by different CBCT systems on the accuracy of approximal caries diagnosis.Thirty-nine extracted non-cavitated human permanent teeth were employed in the study.
Xingmin, Qu, Gang, Li, Zuyan, Zhang, Xuchen, Ma   +3 more
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Accuracy of the Bethe approximation for hyperparameter estimation in probabilistic image processing

Journal of Physics A: Mathematical and General, 2004
After an outline of the Bayesian approach to image processing, one presents both the mean-field and the Bethe approximation for a special class of probabilistic models based on Gaussian distribution. The parameters are estimated by maximizing marginal likelihood.
Tanaka, Kazuyuki, Shouno, Hayaru, Okada, Masato, Titterington, D. M.   +3 more
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Accuracy of statistical image estimates under approximations to Poisson log-likelihood functions

1998 Midwest Symposium on Circuits and Systems (Cat. No. 98CB36268), 2002
Emission Computed Tomography (ECT) is widely applied in medical diagnostic imaging. The available set of measurements is, however, often incomplete and corrupted, and the quality of image reconstruction is enhanced by the computation of a statistically optimal estimate.
J.-B. Thibault, K. Sauer, C. Bouman
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Scale uncertainty compensation for the problem of object's geometry estimations by means of its optical image approximation with subpixel accuracy

2017 XX IEEE International Conference on Soft Computing and Measurements (SCM), 2017
A solution for the estimation of an unknown scale of the optical image is presented. The method does not require any scale reference or additional depth sensing apparatus other than a conventional digital camera. The estimation is performed by the multiparametric model approximation of the image acquired.
Fedor M. Inochkin, Sergey K. Kruglov, Vladimir B. Vasiliev, Igor G. Bronshtein   +3 more
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The Quantitative Accuracy and Efficiency of the Dual Reconstruction Scheme Including a Practical Scatter/Random Approximation in Dynamic PET Imaging

2006 IEEE Nuclear Science Symposium Conference Record, 2006
We describe a time-efficient reconstruction scheme with a practical approximate scatter and random correction for dynamic PET imaging on scanners with large data sets such as the High Resolution Research Tomograph (HRRT). This dual (histogram/list-mode) reconstruction scheme makes use of the efficiency advantage of both histogram and list-mode ...
Ju-Chieh Cheng, Arman Rahmim, Stephan Blinder, Katherine Dinelle, Vesna Sossi   +4 more
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A comparison of the diagnostic accuracy of bitewing, periapical, unfiltered and filtered digital panoramic images for approximal caries detection in posterior teeth

Dentomaxillofacial Radiology, 2008
The aim of this study was to investigate the diagnostic accuracy of conventional bitewing, periapical radiographs, unfiltered and filtered digital panoramic images for the assessment of approximal carious lesions in posterior teeth.20 patients who required bitewing, periapical and panoramic radiographs participated in the study.
Gungor, KAHRAMAN, Erten, H., Akdevelioglu, M., Akarslan, ZÜHRE   +3 more
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ASSESSMENT OF IMAGE SURFACE APPROXIMATION ACCURACY GIVEN BY TRIANGULAR MESHES

2006
Image quality assessment plays an important role in several image processing applications, including data approximation by triangular meshes. The determi- nation of adequate metrics is essential for constructing algorithms that generate high quality models. This paper evaluates a number of different image measures used to refine a given triangular mesh
Oliver Matias van Kaick, Hélio Pedrini
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Accuracy of Spherical Harmonic Approximations for Images of Lambertian Objects under Far and Near Lighting

2004
Various problems in Computer Vision become difficult due to a strong influence of lighting on the images of an object. Recent work showed analytically that the set of all images of a convex, Lambertian object can be accurately approximated by the low-dimensional linear subspace constructed using spherical harmonic functions.
Darya Frolova, Denis Simakov, Ronen Basri   +2 more
openaire   +1 more source