نتایج جستجو برای: uniformity correction

تعداد نتایج: 179312  

Journal: :Nihon Hoshasen Gijutsu Gakkai zasshi 2011
Norikazu Matsutomo Hideo Onishi Akio Nagaki

PURPOSE An attenuation correction is necessary to improve quantitative SPECT evaluation. The aim of this study was to evaluate the performance of several different types of commercial attenuation correction algorithms. METHODS We investigated the performance of four attenuation correction algorithms using a simulation phantom with and without scatter. The attenuation correction was performed ...

2004
Daniel Schläpfer Johannes W. Kaiser Jens Nieke Jason Brazile Klaus I. Itten

The Airborne Prism Experiment (APEX) is currently being built as a demonstrator and calibrator for potential future European spaceborne imaging spectrometers (Itten et al., 1997, Schaepman et al., 2003). It allows the retrieval of traditional and new products for vegetation, geological, limnological and atmospheric sciences. The uniformity of pushbroom imaging spectrometers is affected by spect...

2015
Yuya Nakamura Seiji Tomiguchi Masayuki Tanaka

BACKGROUND Generally, attenuation correction is made by incorporating a linear attenuation coefficient, which is based on the attenuation coefficient map (mu-map) created from a computed tomography scan, into the ordered subsets-expectation maximization reconstruction method in non-uniform domains. A non-uniform Chang's attenuation correction method that uses the mu-map created from a computed ...

Journal: :Frontiers in physics 2015
Timothy C. Zhu Xing Liang Michele M. Kim Jarod C. Finlay Andreea Dimofte Carmen Rodriguez Charles B. Simone Joseph S. Friedberg Keith A. Cengel

Pleural photodynamic therapy (PDT) has been used as an adjuvant treatment with lung-sparing surgical treatment for malignant pleural mesothelioma (MPM). In the current pleural PDT protocol, a moving fiber-based point source is used to deliver the light. The light fluences at multiple locations are monitored by several isotropic detectors placed in the pleural cavity. To improve the delivery of ...

2015
Yubing Tong Jayaram K. Udupa Dewey Odhner Shobhit Sharma Drew A. Torigian

Image non-uniformity and intensity non-standardness are two major hurdles encountered in human and computer interpretation and analysis of magnetic resonance (MR) images. Automated methods for image non-uniformity correction (NC) and intensity standardization (IS) may fail because solutions for them require identifying regions representing the same tissue type for several different tissues, and...

Journal: :NeuroImage 2008
Richard G. Boyes Jeffrey L. Gunter Chris Frost Andrew L. Janke Thomas Yeatman Derek L. G. Hill Matt A. Bernstein Paul M. Thompson Michael Weiner Norbert Schuff Gene E. Alexander Ronald J. Killiany Charles DeCarli Clifford R. Jack Nick C. Fox et al.

Measures of structural brain change based on longitudinal MR imaging are increasingly important but can be degraded by intensity non-uniformity. This non-uniformity can be more pronounced at higher field strengths, or when using multichannel receiver coils. We assessed the ability of the non-parametric non-uniform intensity normalization (N3) technique to correct non-uniformity in 72 volumetric...

2009
N. Azzabou P. Loureiro de Sousa P. G. Carlier

Introduction: In this work, we attempted to correct the non-uniformities generated in lower limbs (calf and thigh) NMRI by RF inhomogeneities. Correction techniques are based in general on prior knowledge about the intensity distribution inside tissues (or tissue magnetic properties) which is not straightforward in case of pathological muscles, as in neuro-muscular disorders. For our applicatio...

Journal: :Journal of Institute of Control, Robotics and Systems 2016

2002
Esteban Vera R. Reeves Sergio N. Torres

The non-uniform response in infrared focal plane array (IRFPA) detectors produces corrupted images with a fixed-pattern noise. In this paper we present a new adaptive scene-based non-uniformity correction (NUC) technique. The method simultaneously estimates detector’s parameters and performs the non-uniformity compensation using a neural approach and a Kalman estimator in a frame by frame recur...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید