WorldWideScience

Sample records for imaging project mi-3

  1. The Multidimensional Integrated Intelligent Imaging project (MI-3)

    International Nuclear Information System (INIS)

    Allinson, N.; Anaxagoras, T.; Aveyard, J.; Arvanitis, C.; Bates, R.; Blue, A.; Bohndiek, S.; Cabello, J.; Chen, L.; Chen, S.; Clark, A.; Clayton, C.; Cook, E.; Cossins, A.; Crooks, J.; El-Gomati, M.; Evans, P.M.; Faruqi, W.; French, M.; Gow, J.

    2009-01-01

    MI-3 is a consortium of 11 universities and research laboratories whose mission is to develop complementary metal-oxide semiconductor (CMOS) active pixel sensors (APS) and to apply these sensors to a range of imaging challenges. A range of sensors has been developed: On-Pixel Intelligent CMOS (OPIC)-designed for in-pixel intelligence; FPN-designed to develop novel techniques for reducing fixed pattern noise; HDR-designed to develop novel techniques for increasing dynamic range; Vanilla/PEAPS-with digital and analogue modes and regions of interest, which has also been back-thinned; Large Area Sensor (LAS)-a novel, stitched LAS; and eLeNA-which develops a range of low noise pixels. Applications being developed include autoradiography, a gamma camera system, radiotherapy verification, tissue diffraction imaging, X-ray phase-contrast imaging, DNA sequencing and electron microscopy.

  2. The Multidimensional Integrated Intelligent Imaging project (MI-3)

    Energy Technology Data Exchange (ETDEWEB)

    Allinson, N.; Anaxagoras, T. [Vision and Information Engineering, University of Sheffield (United Kingdom); Aveyard, J. [Laboratory for Environmental Gene Regulation, University of Liverpool (United Kingdom); Arvanitis, C. [Radiation Physics, University College, London (United Kingdom); Bates, R.; Blue, A. [Experimental Particle Physics, University of Glasgow (United Kingdom); Bohndiek, S. [Radiation Physics, University College, London (United Kingdom); Cabello, J. [Centre for Vision, Speech and Signal Processing, University of Surrey, Guildford (United Kingdom); Chen, L. [Electron Optics, Applied Electromagnetics and Electron Optics, University of York (United Kingdom); Chen, S. [MRC Laboratory for Molecular Biology, Cambridge (United Kingdom); Clark, A. [STFC Rutherford Appleton Laboratories (United Kingdom); Clayton, C. [Vision and Information Engineering, University of Sheffield (United Kingdom); Cook, E. [Radiation Physics, University College, London (United Kingdom); Cossins, A. [Laboratory for Environmental Gene Regulation, University of Liverpool (United Kingdom); Crooks, J. [STFC Rutherford Appleton Laboratories (United Kingdom); El-Gomati, M. [Electron Optics, Applied Electromagnetics and Electron Optics, University of York (United Kingdom); Evans, P.M. [Institute of Cancer Research, Sutton, Surrey SM2 5PT (United Kingdom)], E-mail: phil.evans@icr.ac.uk; Faruqi, W. [MRC Laboratory for Molecular Biology, Cambridge (United Kingdom); French, M. [STFC Rutherford Appleton Laboratories (United Kingdom); Gow, J. [Imaging for Space and Terrestrial Applications, Brunel University, London (United Kingdom)] (and others)

    2009-06-01

    MI-3 is a consortium of 11 universities and research laboratories whose mission is to develop complementary metal-oxide semiconductor (CMOS) active pixel sensors (APS) and to apply these sensors to a range of imaging challenges. A range of sensors has been developed: On-Pixel Intelligent CMOS (OPIC)-designed for in-pixel intelligence; FPN-designed to develop novel techniques for reducing fixed pattern noise; HDR-designed to develop novel techniques for increasing dynamic range; Vanilla/PEAPS-with digital and analogue modes and regions of interest, which has also been back-thinned; Large Area Sensor (LAS)-a novel, stitched LAS; and eLeNA-which develops a range of low noise pixels. Applications being developed include autoradiography, a gamma camera system, radiotherapy verification, tissue diffraction imaging, X-ray phase-contrast imaging, DNA sequencing and electron microscopy.

  3. Projecting Images on a Sphere

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A system for projecting images on an object with a reflective surface. A plurality of image projectors are spaced around the object and synchronized such that each...

  4. Kernel based subspace projection of hyperspectral images

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Nielsen, Allan Aasbjerg; Arngren, Morten

    In hyperspectral image analysis an exploratory approach to analyse the image data is to conduct subspace projections. As linear projections often fail to capture the underlying structure of the data, we present kernel based subspace projections of PCA and Maximum Autocorrelation Factors (MAF......). The MAF projection exploits the fact that interesting phenomena in images typically exhibit spatial autocorrelation. The analysis is based on nearinfrared hyperspectral images of maize grains demonstrating the superiority of the kernelbased MAF method....

  5. Multispectral Panoramic Imaging System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — International Electronic Machines Corporation, a leader in the design of precision imaging systems, will develop an innovative multispectral, panoramic imaging...

  6. Medical imaging projects meet at CERN

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    ENTERVISION, the Research Training Network in 3D Digital Imaging for Cancer Radiation Therapy, successfully passed its mid-term review held at CERN on 11 January. This multidisciplinary project aims at qualifying experts in medical imaging techniques for improved hadron therapy.   ENTERVISION provides training in physics, medicine, electronics, informatics, radiobiology and engineering, as well as a wide range of soft skills, to 16 researchers of different backgrounds and nationalities. The network is funded by the European Commission within the Marie Curie Initial Training Network, and relies on the EU-funded research project ENVISION to provide a training platform for the Marie Curie researchers. The two projects hold their annual meetings jointly, allowing the young researchers to meet senior scientists and to have a full picture of the latest developments in the field beyond their individual research project. ENVISION and ENTERVISION are both co-ordinated by CERN, and the Laboratory hosts t...

  7. Image-projection ion-beam lithography

    International Nuclear Information System (INIS)

    Miller, P.A.

    1989-01-01

    Image-projection ion-beam lithography is an attractive alternative for submicron patterning because it may provide high throughput; it uses demagnification to gain advantages in reticle fabrication, inspection, and lifetime; and it enjoys the precise deposition characteristics of ions which cause essentially no collateral damage. This lithographic option involves extracting low-mass ions (e.g., He + ) from a plasma source, transmitting the ions at low voltage through a stencil reticle, and then accelerating and focusing the ions electrostatically onto a resist-coated wafer. While the advantages of this technology have been demonstrated experimentally by the work of IMS (Austria), many difficulties still impede extension of the technology to the high-volume production of microelectronic devices. We report a computational study of a lithography system designed to address problem areas in field size, telecentricity, and chromatic and geometric aberration. We present a novel ion-column-design approach and conceptual ion-source and column designs which address these issues. We find that image-projection ion-beam technology should in principle meet high-volume-production requirements. The technical success of our present relatively compact-column design requires that a glow-discharge-based ion source (or equivalent cold source) be developed and that moderate further improvement in geometric aberration levels be obtained. Our system requires that image predistortion be employed during reticle fabrication to overcome distortion due to residual image nonlinearity and space-charge forces. This constitutes a software data preparation step, as do correcting for distortions in electron lithography columns and performing proximity-effect corrections. Areas needing further fundamental work are identified

  8. Nuclear Fuel Assembly Assessment Project and Image Categorization

    International Nuclear Information System (INIS)

    Lindsey, C.S.; Lindblad, T.; Waldemark, K.; Hildingsson, Lars

    1998-07-01

    A project has been underway to add digital imaging and processing to the inspection of nuclear fuel by the International Atomic Energy Agency. The ultimate goals are to provide the inspector not only with the advantages of Ccd imaging, such as high sensitivity and digital image enhancements, but also with an intelligent agent that can analyze the images and provide useful information about the fuel assemblies in real time. The project is still in the early stages and several interesting sub-projects have been inspired. Here we give first a review of the work on the fuel assembly image analysis and then give a brief status report on one of these sub-projects that concerns automatic categorization of fuel assembly images. The technique could be of benefit to the general challenge of image categorization

  9. Space-Ready Advanced Imaging System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II effort Toyon will increase the state-of-the-art for video/image systems. This will include digital image compression algorithms as well as system...

  10. Variance in parametric images: direct estimation from parametric projections

    International Nuclear Information System (INIS)

    Maguire, R.P.; Leenders, K.L.; Spyrou, N.M.

    2000-01-01

    Recent work has shown that it is possible to apply linear kinetic models to dynamic projection data in PET in order to calculate parameter projections. These can subsequently be back-projected to form parametric images - maps of parameters of physiological interest. Critical to the application of these maps, to test for significant changes between normal and pathophysiology, is an assessment of the statistical uncertainty. In this context, parametric images also include simple integral images from, e.g., [O-15]-water used to calculate statistical parametric maps (SPMs). This paper revisits the concept of parameter projections and presents a more general formulation of the parameter projection derivation as well as a method to estimate parameter variance in projection space, showing which analysis methods (models) can be used. Using simulated pharmacokinetic image data we show that a method based on an analysis in projection space inherently calculates the mathematically rigorous pixel variance. This results in an estimation which is as accurate as either estimating variance in image space during model fitting, or estimation by comparison across sets of parametric images - as might be done between individuals in a group pharmacokinetic PET study. The method based on projections has, however, a higher computational efficiency, and is also shown to be more precise, as reflected in smooth variance distribution images when compared to the other methods. (author)

  11. Adaptive Computed Tomography Imaging Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The present proposal describes the development of an adaptive Computed Tomography Imaging Spectrometer (CTIS), or "Snapshot" spectrometer which can "instantaneously"...

  12. Synthetic Imaging Maneuver Optimization (SIMO) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space-based interferometry missions have the potential to revolutionize imaging and astrometry, providing observations of unprecedented accuracy. Realizing the full...

  13. [Managing digital medical imaging projects in healthcare services: lessons learned].

    Science.gov (United States)

    Rojas de la Escalera, D

    2013-01-01

    Medical imaging is one of the most important diagnostic instruments in clinical practice. The technological development of digital medical imaging has enabled healthcare services to undertake large scale projects that require the participation and collaboration of many professionals of varied backgrounds and interests as well as substantial investments in infrastructures. Rather than focusing on systems for dealing with digital medical images, this article deals with the management of projects for implementing these systems, reviewing various organizational, technological, and human factors that are critical to ensure the success of these projects and to guarantee the compatibility and integration of digital medical imaging systems with other health information systems. To this end, the author relates several lessons learned from a review of the literature and the author's own experience in the technical coordination of digital medical imaging projects. Copyright © 2012 SERAM. Published by Elsevier Espana. All rights reserved.

  14. Tomographic image reconstruction from continuous projections

    NARCIS (Netherlands)

    J. Cant (Jeroen); W.J. Palenstijn (Willem Jan); G. Behiels; J. Sijbers (Jan)

    2014-01-01

    htmlabstractAn important design aspect in tomographic image reconstruction is the choice between a step-and-shoot protocol versus continuous X-ray tube movement for image acquisition. A step-and-shoot protocol implies a perfectly still tube during X-ray exposure, and hence involves moving the tube

  15. Synthetic Imaging Maneuver Optimization (SIMO) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aurora Flight Sciences (AFS), in collaboration with the MIT Space Systems Laboratory (MIT-SSL), proposed the Synthetic Imaging Maneuver Optimization (SIMO) program...

  16. Miniaturized Airborne Imaging Central Server System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a miniaturized airborne imaging central server system (MAICSS). MAICSS is designed as a high-performance-computer-based electronic backend that...

  17. Miniaturized Airborne Imaging Central Server System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a miniaturized airborne imaging central server system (MAICSS). MAICSS is designed as a high-performance computer-based electronic backend that...

  18. Ge Quantum Dot Infrared Imaging Camera Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations Incorporated proposes to develop a high performance Ge quantum dots-based infrared (IR) imaging camera on Si substrate. The high sensitivity, large...

  19. Airborne Wide Area Imager for Wildfire Mapping and Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An advanced airborne imaging system for fire detection/mapping is proposed. The goal of the project is to improve control and management of wildfires in order to...

  20. The Assessment of Distortion in Neurosurgical Image Overlay Projection.

    Science.gov (United States)

    Vakharia, Nilesh N; Paraskevopoulos, Dimitris; Lang, Jozsef; Vakharia, Vejay N

    2016-02-01

    Numerous studies have demonstrated the superiority of neuronavigation during neurosurgical procedures compared to non-neuronavigation-based procedures. Limitations to neuronavigation systems include the need for the surgeons to avert their gaze from the surgical field and the cost of the systems, especially for hospitals in developing countries. Overlay projection of imaging directly onto the patient allows localization of intracranial structures. A previous study using overlay projection demonstrated the accuracy of image coregistration for a lesion in the temporal region but did not assess image distortion when projecting onto other anatomical locations. Our aim is to quantify this distortion and establish which regions of the skull would be most suitable for overlay projection. Using the difference in size of a square grid when projected onto an anatomically accurate model skull and a flat surface, from the same distance, we were able to calculate the degree of image distortion when projecting onto the skull from the anterior, posterior, superior, and lateral aspects. Measuring the size of a square when projected onto a flat surface from different distances allowed us to model change in lesion size when projecting a deep structure onto the skull surface. Using 2 mm as the upper limit for distortion, our results show that images can be accurately projected onto the majority (81.4%) of the surface of the skull. Our results support the use of image overlay projection in regions with ≤2 mm distortion to assist with localization of intracranial lesions at a fraction of the cost of existing methods. © The Author(s) 2015.

  1. Image reconstruction technique using projection data from neutron tomography system

    Directory of Open Access Journals (Sweden)

    Waleed Abd el Bar

    2015-12-01

    Full Text Available Neutron tomography is a very powerful technique for nondestructive evaluation of heavy industrial components as well as for soft hydrogenous materials enclosed in heavy metals which are usually difficult to image using X-rays. Due to the properties of the image acquisition system, the projection images are distorted by several artifacts, and these reduce the quality of the reconstruction. In order to eliminate these harmful effects the projection images should be corrected before reconstruction. This paper gives a description of a filter back projection (FBP technique, which is used for reconstruction of projected data obtained from transmission measurements by neutron tomography system We demonstrated the use of spatial Discrete Fourier Transform (DFT and the 2D Inverse DFT in the formulation of the method, and outlined the theory of reconstruction of a 2D neutron image from a sequence of 1D projections taken at different angles between 0 and π in MATLAB environment. Projections are generated by applying the Radon transform to the original image at different angles.

  2. Total Variation and Tomographic Imaging from Projections

    DEFF Research Database (Denmark)

    Hansen, Per Christian; Jørgensen, Jakob Heide

    2011-01-01

    or 3D reconstruction from noisy projections. We demonstrate that for a small signal-to-noise ratio, this new approach allows us to compute better (i.e., more reliable) reconstructions than those obtained by classical methods. This is possible due to the use of the TV reconstruction model, which...

  3. Speckle averaging system for laser raster-scan image projection

    Science.gov (United States)

    Tiszauer, Detlev H.; Hackel, Lloyd A.

    1998-03-17

    The viewers' perception of laser speckle in a laser-scanned image projection system is modified or eliminated by the addition of an optical deflection system that effectively presents a new speckle realization at each point on the viewing screen to each viewer for every scan across the field. The speckle averaging is accomplished without introduction of spurious imaging artifacts.

  4. Quantitative imaging studies with PET VI. Project II

    International Nuclear Information System (INIS)

    Copper, M.; Chen, C.T.; Yasillo, N.; Gatley, J.; Ortega, C.; DeJesus, O.; Friedman, A.

    1985-01-01

    This project is focused upon the development of hardware and software to improve PET image analysis and upon clinical applications of PET. In this report the laboratory's progress in various attenuation correction methods for brain imaging are described. The use of time-of-flight information for image reconstruction is evaluated. The location of dopamine D1 and D2 receptors in brain was found to be largely in the basal ganghia. 1 tab. (DT)

  5. Learning linear discriminant projections for dimensionality reduction of image descriptors.

    Science.gov (United States)

    Cai, Hongping; Mikolajczyk, Krystian; Matas, Jiri

    2011-02-01

    In this paper, we present Linear Discriminant Projections (LDP) for reducing dimensionality and improving discriminability of local image descriptors. We place LDP into the context of state-of-the-art discriminant projections and analyze its properties. LDP requires a large set of training data with point-to-point correspondence ground truth. We demonstrate that training data produced by a simulation of image transformations leads to nearly the same results as the real data with correspondence ground truth. This makes it possible to apply LDP as well as other discriminant projection approaches to the problems where the correspondence ground truth is not available, such as image categorization. We perform an extensive experimental evaluation on standard data sets in the context of image matching and categorization. We demonstrate that LDP enables significant dimensionality reduction of local descriptors and performance increases in different applications. The results improve upon the state-of-the-art recognition performance with simultaneous dimensionality reduction from 128 to 30.

  6. Compressed Sensing Inspired Image Reconstruction from Overlapped Projections

    Directory of Open Access Journals (Sweden)

    Lin Yang

    2010-01-01

    Full Text Available The key idea discussed in this paper is to reconstruct an image from overlapped projections so that the data acquisition process can be shortened while the image quality remains essentially uncompromised. To perform image reconstruction from overlapped projections, the conventional reconstruction approach (e.g., filtered backprojection (FBP algorithms cannot be directly used because of two problems. First, overlapped projections represent an imaging system in terms of summed exponentials, which cannot be transformed into a linear form. Second, the overlapped measurement carries less information than the traditional line integrals. To meet these challenges, we propose a compressive sensing-(CS- based iterative algorithm for reconstruction from overlapped data. This algorithm starts with a good initial guess, relies on adaptive linearization, and minimizes the total variation (TV. Then, we demonstrated the feasibility of this algorithm in numerical tests.

  7. Compressed Sensing Inspired Image Reconstruction from Overlapped Projections

    Science.gov (United States)

    Yang, Lin; Lu, Yang; Wang, Ge

    2010-01-01

    The key idea discussed in this paper is to reconstruct an image from overlapped projections so that the data acquisition process can be shortened while the image quality remains essentially uncompromised. To perform image reconstruction from overlapped projections, the conventional reconstruction approach (e.g., filtered backprojection (FBP) algorithms) cannot be directly used because of two problems. First, overlapped projections represent an imaging system in terms of summed exponentials, which cannot be transformed into a linear form. Second, the overlapped measurement carries less information than the traditional line integrals. To meet these challenges, we propose a compressive sensing-(CS-) based iterative algorithm for reconstruction from overlapped data. This algorithm starts with a good initial guess, relies on adaptive linearization, and minimizes the total variation (TV). Then, we demonstrated the feasibility of this algorithm in numerical tests. PMID:20689701

  8. Micro Aerial Projector Stabilizing Projected Images Of An Airborne Robotics Projection Platform

    Science.gov (United States)

    2016-10-09

    Micro Aerial Projector - Stabilizing Projected Images Of An Airborne Robotics Projection Platform Werner Alexander Isop1, Jesus Pestana1, Gabriele...combining augmented reality and mobile robotics into a new form of human-machine interaction. Specifically, we introduce a small semi-autonomous micro aerial...it as a robotic companion, which follows the user and is able to project supportive information in the 3D environment. Fig. 1 shows an example where

  9. A novel augmented reality system of image projection for image-guided neurosurgery.

    Science.gov (United States)

    Mahvash, Mehran; Besharati Tabrizi, Leila

    2013-05-01

    Augmented reality systems combine virtual images with a real environment. To design and develop an augmented reality system for image-guided surgery of brain tumors using image projection. A virtual image was created in two ways: (1) MRI-based 3D model of the head matched with the segmented lesion of a patient using MRIcro software (version 1.4, freeware, Chris Rorden) and (2) Digital photograph based model in which the tumor region was drawn using image-editing software. The real environment was simulated with a head phantom. For direct projection of the virtual image to the head phantom, a commercially available video projector (PicoPix 1020, Philips) was used. The position and size of the virtual image was adjusted manually for registration, which was performed using anatomical landmarks and fiducial markers position. An augmented reality system for image-guided neurosurgery using direct image projection has been designed successfully and implemented in first evaluation with promising results. The virtual image could be projected to the head phantom and was registered manually. Accurate registration (mean projection error: 0.3 mm) was performed using anatomical landmarks and fiducial markers position. The direct projection of a virtual image to the patients head, skull, or brain surface in real time is an augmented reality system that can be used for image-guided neurosurgery. In this paper, the first evaluation of the system is presented. The encouraging first visualization results indicate that the presented augmented reality system might be an important enhancement of image-guided neurosurgery.

  10. Projection Operators and Moment Invariants to Image Blurring

    Czech Academy of Sciences Publication Activity Database

    Flusser, Jan; Suk, Tomáš; Boldyš, Jiří; Zitová, Barbara

    2015-01-01

    Roč. 37, č. 4 (2015), s. 786-802 ISSN 0162-8828 R&D Projects: GA ČR GA13-29225S; GA ČR GAP103/11/1552 Institutional support: RVO:67985556 Keywords : Blurred image * N-fold rotation symmetry * projection operators * image moments * moment invariants * blur invariants * object recognition Subject RIV: JD - Computer Applications, Robotics Impact factor: 6.077, year: 2015 http://library.utia.cas.cz/separaty/2014/ZOI/flusser-0434521.pdf

  11. Discriminating Projections for Estimating Face Age in Wild Images

    Energy Technology Data Exchange (ETDEWEB)

    Tokola, Ryan A [ORNL; Bolme, David S [ORNL; Ricanek, Karl [ORNL; Barstow, Del R [ORNL; Boehnen, Chris Bensing [ORNL

    2014-01-01

    We introduce a novel approach to estimating the age of a human from a single uncontrolled image. Current face age estimation algorithms work well in highly controlled images, and some are robust to changes in illumination, but it is usually assumed that images are close to frontal. This bias is clearly seen in the datasets that are commonly used to evaluate age estimation, which either entirely or mostly consist of frontal images. Using pose-specific projections, our algorithm maps image features into a pose-insensitive latent space that is discriminative with respect to age. Age estimation is then performed using a multi-class SVM. We show that our approach outperforms other published results on the Images of Groups dataset, which is the only age-related dataset with a non-trivial number of off-axis face images, and that we are competitive with recent age estimation algorithms on the mostly-frontal FG-NET dataset. We also experimentally demonstrate that our feature projections introduce insensitivity to pose.

  12. Integrated variable projection approach (IVAPA) for parallel magnetic resonance imaging.

    Science.gov (United States)

    Zhang, Qiao; Sheng, Jinhua

    2012-10-01

    Parallel magnetic resonance imaging (pMRI) is a fast method which requires algorithms for the reconstructing image from a small number of measured k-space lines. The accurate estimation of the coil sensitivity functions is still a challenging problem in parallel imaging. The joint estimation of the coil sensitivity functions and the desired image has recently been proposed to improve the situation by iteratively optimizing both the coil sensitivity functions and the image reconstruction. It regards both the coil sensitivities and the desired images as unknowns to be solved for jointly. In this paper, we propose an integrated variable projection approach (IVAPA) for pMRI, which integrates two individual processing steps (coil sensitivity estimation and image reconstruction) into a single processing step to improve the accuracy of the coil sensitivity estimation using the variable projection approach. The method is demonstrated to be able to give an optimal solution with considerably reduced artifacts for high reduction factors and a low number of auto-calibration signal (ACS) lines, and our implementation has a fast convergence rate. The performance of the proposed method is evaluated using a set of in vivo experiment data. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Object-Image Correspondence for Algebraic Curves under Projections

    Directory of Open Access Journals (Sweden)

    Joseph M. Burdis

    2013-03-01

    Full Text Available We present a novel algorithm for deciding whether a given planar curve is an image of a given spatial curve, obtained by a central or a parallel projection with unknown parameters. The motivation comes from the problem of establishing a correspondence between an object and an image, taken by a camera with unknown position and parameters. A straightforward approach to this problem consists of setting up a system of conditions on the projection parameters and then checking whether or not this system has a solution. The computational advantage of the algorithm presented here, in comparison to algorithms based on the straightforward approach, lies in a significant reduction of a number of real parameters that need to be eliminated in order to establish existence or non-existence of a projection that maps a given spatial curve to a given planar curve. Our algorithm is based on projection criteria that reduce the projection problem to a certain modification of the equivalence problem of planar curves under affine and projective transformations. To solve the latter problem we make an algebraic adaptation of signature construction that has been used to solve the equivalence problems for smooth curves. We introduce a notion of a classifying set of rational differential invariants and produce explicit formulas for such invariants for the actions of the projective and the affine groups on the plane.

  14. A study of images of Projective Angles of pulmonary veins

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jue [Beijing Anzhen Hospital, Beijing (China); Zhaoqi, Zhang [Beijing Anzhen Hospital, Beijing (China)], E-mail: zhaoqi5000@vip.sohu.com; Yu Wei; Miao Cuilian; Yan Zixu; Zhao Yike [Beijing Anzhen Hospital, Beijing (China)

    2009-09-15

    Aims: In images of magnetic resonance and computed tomography (CT) there are visible angles between pulmonary veins and the coronary, transversal or sagittal section of body. In this study these angles are measured and defined as Projective Angles of pulmonary veins. Several possible influential factors and characters of distribution are studied and analyzed for a better understanding of this imaging anatomic character of pulmonary veins. And it could be the anatomic base of adjusting correctly the angle of the central X-ray of the angiography of pulmonary veins undergoing the catheter ablation of atrial fibrillation (AF). Method: Images of contrast enhanced magnetic resonance angiography (CEMRA) and contrast enhanced computer tomography (CECT) of the left atrium and pulmonary veins of 137 health objects and patients with atrial fibrillation (AF) are processed with the technique of post-processing, and Projective Angles to the coronary and transversal sections are measured and analyzed statistically. Result: Project Angles of pulmonary veins are one of real and steady imaging anatomic characteristics of pulmonary veins. The statistical distribution of variables is relatively concentrated, with a fairly good representation of average value. It is possible to improve the angle of the central X-ray according to the average value in the selective angiography of pulmonary veins undergoing the catheter ablation of AF.

  15. Parametric image reconstruction using spectral analysis of PET projection data

    International Nuclear Information System (INIS)

    Meikle, Steven R.; Matthews, Julian C.; Cunningham, Vincent J.; Bailey, Dale L.; Livieratos, Lefteris; Jones, Terry; Price, Pat

    1998-01-01

    Spectral analysis is a general modelling approach that enables calculation of parametric images from reconstructed tracer kinetic data independent of an assumed compartmental structure. We investigated the validity of applying spectral analysis directly to projection data motivated by the advantages that: (i) the number of reconstructions is reduced by an order of magnitude and (ii) iterative reconstruction becomes practical which may improve signal-to-noise ratio (SNR). A dynamic software phantom with typical 2-[ 11 C]thymidine kinetics was used to compare projection-based and image-based methods and to assess bias-variance trade-offs using iterative expectation maximization (EM) reconstruction. We found that the two approaches are not exactly equivalent due to properties of the non-negative least-squares algorithm. However, the differences are small ( 1 and, to a lesser extent, VD). The optimal number of EM iterations was 15-30 with up to a two-fold improvement in SNR over filtered back projection. We conclude that projection-based spectral analysis with EM reconstruction yields accurate parametric images with high SNR and has potential application to a wide range of positron emission tomography ligands. (author)

  16. Functional imaging of cortical feedback projections to the olfactory bulb

    Directory of Open Access Journals (Sweden)

    Markus eRothermel

    2014-07-01

    Full Text Available Processing of sensory information is substantially shaped by centrifugal, or feedback, projections from higher cortical areas, yet the functional properties of these projections are poorly characterized. Here, we used genetically-encoded calcium sensors (GCaMPs to functionally image activation of centrifugal projections targeting the olfactory bulb (OB. The OB receives massive centrifugal input from cortical areas but there has been as yet no characterization of their activity in vivo. We focused on projections to the OB from the anterior olfactory nucleus (AON, a major source of cortical feedback to the OB. We expressed GCaMP selectively in AON projection neurons using a mouse line expressing Cre recombinase (Cre in these neurons and Cre-dependent viral vectors injected into AON, allowing us to image GCaMP fluorescence signals from their axon terminals in the OB. Electrical stimulation of AON evoked large fluorescence signals that could be imaged from the dorsal OB surface in vivo. Surprisingly, odorants also evoked large signals that were transient and coupled to odorant inhalation both in the anesthetized and awake mouse, suggesting that feedback from AON to the OB is rapid and robust across different brain states. The strength of AON feedback signals increased during wakefulness, suggesting a state-dependent modulation of cortical feedback to the OB. Two-photon GCaMP imaging revealed that different odorants activated different subsets of centrifugal AON axons and could elicit both excitation and suppression in different axons, indicating a surprising richness in the representation of odor information by cortical feedback to the OB. Finally, we found that activating neuromodulatory centers such as basal forebrain drove AON inputs to the OB independent of odorant stimulation. Our results point to the AON as a multifunctional cortical area that provides ongoing feedback to the OB and also serves as a descending relay for other neuromodulatory

  17. Detecting image edge from projections using Discrete Radon Transform properties

    International Nuclear Information System (INIS)

    Wang Jing; Li Zheng

    2004-01-01

    The authors studied the distributed 2-D convolution of Discrete Radon Transform, and developed a method of image processing used directly on the projection data in Computerized Tomography. The special case of edge detection and its computer simulated results are demonstrated. The paper also compared the traditional image edge detection method with the new method, analyzed the effecting factors of calculating time. It is proved that the new method is superior to the traditional method in calculating time. The advantage and application potential of the new method are also discussed. (authors)

  18. M2DART: a real image rear-projection display

    Science.gov (United States)

    Best, Leonard G.; Wight, Don R.; Peppler, Philipp W.

    1999-08-01

    The Mobile Modular Display for Advanced Research and Training (M2DART) was designed and fabricated at the Air Force Research Laboratory (AFRL) Warfighter Training Research Facility. The M2DART is part of a long term development goal of AFRL to produce a display and imaging system combination with significantly improved visual acuity in a full field-of- view/field-of-regard environment. The M2DART is an eight- channel, state-of-the-art, real image, rear-projection visual display system. It is a full color, high resolution, wraparound display designed for use with single-seat cockpit simulators. Depending on the number of available image generator channels, the system allows for a wide instantaneous field-of-view, when used in conjunction with a magnetic head tracker and video router combination to provide a full field- of-regard. The display is designed to accommodate a variety of visual image generators and cockpit simulators. The system uses commercial off-the-shelf (COTS) BARCO CRT projectors to display the out-the-window (OTW) visual imagery to the pilot. The M2DART concept demonstrates that a rear-projected, real image approach is a viable means of providing full color imagery to flight simulators with improved brightness and resolution characteristics. The final design of the M2DART represents a balance between such considerations as training requirements, the number of available image generator channels, system resolution, field of view, brightness, image stability and maintainability. This paper will provide a system description, which includes design trade-off considerations, hardware configuration, screen geometry, field of view, and performance specifications.

  19. Measuring Brand Image Effects of Flagship Projects for Place Brands

    DEFF Research Database (Denmark)

    Zenker, Sebastian; Beckmann, Suzanne C.

    2013-01-01

    , which was originally developed for product brands. An experimental design was used to first measure the Hamburg brand as such and then the changes in the brand perceptions after priming the participants (N=209) for one of the three different flagship projects. The findings reveal several important......Cities invest large sums of money in ‘flagship projects’, with the aim of not only developing the city as such, but also changing the perceptions of the city brand towards a desired image. The city of Hamburg, Germany, is currently investing euro575 million in order to build a new symphony hall...... (Elbphilharmonie), euro400 million to develop the ‘International Architectural Fair’ and it is also considering candidature again for the ‘Olympic Games’ in 2024/2028. As assessing the image effects of such projects is rather difficult, this article introduces an improved version of the Brand Concept Map approach...

  20. An adaptive filtered back-projection for photoacoustic image reconstruction

    International Nuclear Information System (INIS)

    Huang, He; Bustamante, Gilbert; Peterson, Ralph; Ye, Jing Yong

    2015-01-01

    Purpose: The purpose of this study is to develop an improved filtered-back-projection (FBP) algorithm for photoacoustic tomography (PAT), which allows image reconstruction with higher quality compared to images reconstructed through traditional algorithms. Methods: A rigorous expression of a weighting function has been derived directly from a photoacoustic wave equation and used as a ramp filter in Fourier domain. The authors’ new algorithm utilizes this weighting function to precisely calculate each photoacoustic signal’s contribution and then reconstructs the image based on the retarded potential generated from the photoacoustic sources. In addition, an adaptive criterion has been derived for selecting the cutoff frequency of a low pass filter. Two computational phantoms were created to test the algorithm. The first phantom contained five spheres with each sphere having different absorbances. The phantom was used to test the capability for correctly representing both the geometry and the relative absorbed energy in a planar measurement system. The authors also used another phantom containing absorbers of different sizes with overlapping geometry to evaluate the performance of the new method for complicated geometry. In addition, random noise background was added to the simulated data, which were obtained by using an arc-shaped array of 50 evenly distributed transducers that spanned 160° over a circle with a radius of 65 mm. A normalized factor between the neighbored transducers was applied for correcting measurement signals in PAT simulations. The authors assumed that the scanned object was mounted on a holder that rotated over the full 360° and the scans were set to a sampling rate of 20.48 MHz. Results: The authors have obtained reconstructed images of the computerized phantoms by utilizing the new FBP algorithm. From the reconstructed image of the first phantom, one can see that this new approach allows not only obtaining a sharp image but also showing

  1. Qualitative and quantitative analysis of reconstructed images using projections with noises

    International Nuclear Information System (INIS)

    Lopes, R.T.; Assis, J.T. de

    1988-01-01

    The reconstruction of a two-dimencional image from one-dimensional projections in an analytic algorithm ''convolution method'' is simulated on a microcomputer. In this work it was analysed the effects caused in the reconstructed image in function of the number of projections and noise level added to the projection data. Qualitative and quantitative (distortion and image noise) comparison were done with the original image and the reconstructed images. (author) [pt

  2. Sparse Nonlinear Electromagnetic Imaging Accelerated With Projected Steepest Descent Algorithm

    KAUST Repository

    Desmal, Abdulla

    2017-04-03

    An efficient electromagnetic inversion scheme for imaging sparse 3-D domains is proposed. The scheme achieves its efficiency and accuracy by integrating two concepts. First, the nonlinear optimization problem is constrained using L₀ or L₁-norm of the solution as the penalty term to alleviate the ill-posedness of the inverse problem. The resulting Tikhonov minimization problem is solved using nonlinear Landweber iterations (NLW). Second, the efficiency of the NLW is significantly increased using a steepest descent algorithm. The algorithm uses a projection operator to enforce the sparsity constraint by thresholding the solution at every iteration. Thresholding level and iteration step are selected carefully to increase the efficiency without sacrificing the convergence of the algorithm. Numerical results demonstrate the efficiency and accuracy of the proposed imaging scheme in reconstructing sparse 3-D dielectric profiles.

  3. Final Project Report: Imaging Fault Zones Using a Novel Elastic Reverse-Time Migration Imaging Technique

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lianjie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chen, Ting [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tan, Sirui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lin, Youzuo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gao, Kai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-10

    Imaging fault zones and fractures is crucial for geothermal operators, providing important information for reservoir evaluation and management strategies. However, there are no existing techniques available for directly and clearly imaging fault zones, particularly for steeply dipping faults and fracture zones. In this project, we developed novel acoustic- and elastic-waveform inversion methods for high-resolution velocity model building. In addition, we developed acoustic and elastic reverse-time migration methods for high-resolution subsurface imaging of complex subsurface structures and steeply-dipping fault/fracture zones. We first evaluated and verified the improved capabilities of our newly developed seismic inversion and migration imaging methods using synthetic seismic data. Our numerical tests verified that our new methods directly image subsurface fracture/fault zones using surface seismic reflection data. We then applied our novel seismic inversion and migration imaging methods to a field 3D surface seismic dataset acquired at the Soda Lake geothermal field using Vibroseis sources. Our migration images of the Soda Lake geothermal field obtained using our seismic inversion and migration imaging algorithms revealed several possible fault/fracture zones. AltaRock Energy, Inc. is working with Cyrq Energy, Inc. to refine the geologic interpretation at the Soda Lake geothermal field. Trenton Cladouhos, Senior Vice President R&D of AltaRock, was very interested in our imaging results of 3D surface seismic data from the Soda Lake geothermal field. He planed to perform detailed interpretation of our images in collaboration with James Faulds and Holly McLachlan of University of Nevada at Reno. Using our high-resolution seismic inversion and migration imaging results can help determine the optimal locations to drill wells for geothermal energy production and reduce the risk of geothermal exploration.

  4. A new framework of image reconstruction from fan beam projections

    International Nuclear Information System (INIS)

    Chen, G.-H.

    2003-01-01

    In this paper, we present a unified framework to reconstruct images for both fan beam and cone beam projections. The important feature of our theoretical framework is that it does not depend on the classical concept of the Radon transform at all. This property allows us to directly generalize the ideas and techniques developed in this paper to the cone beam reconstruction problem. In this paper, we extract such a framework from developing a new image reconstruction scheme from fan beam projections. Our new scheme also provides us new understanding of fan beam reconstruction problem. Our main results for the fan beam reconstruction are the following: First, we derive a general reconstruction scheme, in which the data sufficiency condition is transparently revealed by the reconstruction formula. Specifically, the data sufficiency condition for an accurate reconstruction of a region of interest (ROI) is that all the lines passing through the ROI must intersect the source trajectory at least once. Second, we further simplify the general reconstruction scheme by following three major steps of our new framework: (i) using symmetries of intermediate function; (ii) handling the data redundancy; (iii) changing discrete summation over the possible focal points into an integral along the source trajectory. After these steps, we obtain a new filtered backprojection algorithm. The key characteristic of this new algorithm is to take derivative of measured data with respect to the trajectory parameter. In practice, we can trade this derivative to some other continuous functions. In the configuration of a circular source trajectory with a third generation arc/collinear detector, we demonstrate how to remove the undesirable derivative of measured projection data. It results in a new algorithm for the sequential reconstruction of a ROI with a general normalized weighting function

  5. Image applications for coastal resource planning: Elkhorn Slough Pilot Project

    Science.gov (United States)

    Kvitek, Rikk G.; Sharp, Gary D.; VanCoops, Jonathan; Fitzgerald, Michael

    1995-01-01

    The purpose of this project has been to evaluate the utility of digital spectral imagery at two levels of resolution for large scale, accurate, auto-classification of land cover along the Central California Coast. Although remote sensing technology offers obvious advantages over on-the-ground mapping, there are substantial trade-offs that must be made between resolving power and costs. Higher resolution images can theoretically be used to identify smaller habitat patches, but they usually require more scenes to cover a given area and processing these images is computationally intense requiring much more computer time and memory. Lower resolution images can cover much larger areas, are less costly to store, process, and manipulate, but due to their larger pixel size can lack the resolving power of the denser images. This lack of resolving power can be critical in regions such as the Central California Coast where important habitat change often occurs on a scale of 10 meters. Our approach has been to compare vegetation and habitat classification results from two aircraft-based spectral scenes covering the same study area but at different levels of resolution with a previously produced ground-truthed land cover base map of the area. Both of the spectral images used for this project were of significantly higher resolution than the satellite-based LandSat scenes used in the C-CAP program. The lower reaches of the Elkhorn Slough watershed was chosen as an ideal study site because it encompasses a suite of important vegetation types and habitat loss processes characteristic of the central coast region. Dramatic habitat alterations have and are occurring within the Elkhorn Slough drainage area, including erosion and sedimentation, land use conversion, wetland loss, and incremental loss due to development and encroachnnent by agriculture. Additonally, much attention has already been focused on the Elkhorn Slough due to its status as a National Marine Education and Research

  6. Implementation of GPU-accelerated back projection for EPR imaging.

    Science.gov (United States)

    Qiao, Zhiwei; Redler, Gage; Epel, Boris; Qian, Yuhua; Halpern, Howard

    2015-01-01

    Electron paramagnetic resonance (EPR) Imaging (EPRI) is a robust method for measuring in vivo oxygen concentration (pO2). For 3D pulse EPRI, a commonly used reconstruction algorithm is the filtered backprojection (FBP) algorithm, in which the backprojection process is computationally intensive and may be time consuming when implemented on a CPU. A multistage implementation of the backprojection can be used for acceleration, however it is not flexible (requires equal linear angle projection distribution) and may still be time consuming. In this work, single-stage backprojection is implemented on a GPU (Graphics Processing Units) having 1152 cores to accelerate the process. The GPU implementation results in acceleration by over a factor of 200 overall and by over a factor of 3500 if only the computing time is considered. Some important experiences regarding the implementation of GPU-accelerated backprojection for EPRI are summarized. The resulting accelerated image reconstruction is useful for real-time image reconstruction monitoring and other time sensitive applications.

  7. Multiview Discriminative Geometry Preserving Projection for Image Classification

    Directory of Open Access Journals (Sweden)

    Ziqiang Wang

    2014-01-01

    Full Text Available In many image classification applications, it is common to extract multiple visual features from different views to describe an image. Since different visual features have their own specific statistical properties and discriminative powers for image classification, the conventional solution for multiple view data is to concatenate these feature vectors as a new feature vector. However, this simple concatenation strategy not only ignores the complementary nature of different views, but also ends up with “curse of dimensionality.” To address this problem, we propose a novel multiview subspace learning algorithm in this paper, named multiview discriminative geometry preserving projection (MDGPP for feature extraction and classification. MDGPP can not only preserve the intraclass geometry and interclass discrimination information under a single view, but also explore the complementary property of different views to obtain a low-dimensional optimal consensus embedding by using an alternating-optimization-based iterative algorithm. Experimental results on face recognition and facial expression recognition demonstrate the effectiveness of the proposed algorithm.

  8. Maximum intensity projection MR angiography using shifted image data

    International Nuclear Information System (INIS)

    Machida, Yoshio; Ichinose, Nobuyasu; Hatanaka, Masahiko; Goro, Takehiko; Kitake, Shinichi; Hatta, Junicchi.

    1992-01-01

    The quality of MR angiograms has been significantly improved in past several years. Spatial resolution, however, is not sufficient for clinical use. On the other hand, MR image data can be filled at anywhere using Fourier shift theorem, and the quality of multi-planar reformed image has been reported to be improved remarkably using 'shifted data'. In this paper, we have clarified the efficiency of 'shifted data' for maximum intensity projection MR angiography. Our experimental studies and theoretical consideration showd that the quality of MR angiograms has been significantly improved using 'shifted data' as follows; 1) remarkable reduction of mosaic artifact, 2) improvement of spatial continuity for the blood vessels, and 3) reduction of variance for the signal intensity along the blood vessels. In other words, the angiograms looks much 'finer' than conventional ones, although the spatial resolution is not improved theoretically. Furthermore, we found the quality of MR angiograms dose not improve significantly with the 'shifted data' more than twice as dense as ordinal ones. (author)

  9. The projected and perceived image of the United Republic of Tanzania

    OpenAIRE

    Koerte, Tammy Reiko

    2009-01-01

    While Tanzania has enjoyed increasing popularity as a tourism destination, there is a lack of research on Tanzania's tourism image. Tanzania 's tourism growth, however, depends upon the congruency of its projected and perceived images. This research examines the government's projected image of Tanzania and measures its congruency with the image perceived by past visitors to Tanzania. The study utilized the Tanzania Tourist Board and Tanzania Travel and Tourism Online websites as well as 36...

  10. A Gimbal-Stabilized Compact Hyperspectral Imaging System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Gimbal-stabilized Compact Hyperspectral Imaging System (GCHIS) fully integrates multi-sensor spectral imaging, stereovision, GPS and inertial measurement,...

  11. Image/patient registration from (partial) projection data by the Fourier phase matching method

    International Nuclear Information System (INIS)

    Weiguo Lu; You, J.

    1999-01-01

    A technique for 2D or 3D image/patient registration, PFPM (projection based Fourier phase matching method), is proposed. This technique provides image/patient registration directly from sequential tomographic projection data. The method can also deal with image files by generating 2D Radon transforms slice by slice. The registration in projection space is done by calculating a Fourier invariant (FI) descriptor for each one-dimensional projection datum, and then registering the FI descriptor by the Fourier phase matching (FPM) method. The algorithm has been tested on both synthetic and experimental data. When dealing with translated, rotated and uniformly scaled 2D image registration, the performance of the PFPM method is comparable to that of the IFPM (image based Fourier phase matching) method in robustness, efficiency, insensitivity to the offset between images, and registration time. The advantages of the former are that subpixel resolution is feasible, and it is more insensitive to image noise due to the averaging effect of the projection acquisition. Furthermore, the PFPM method offers the ability to generalize to 3D image/patient registration and to register partial projection data. By applying patient registration directly from tomographic projection data, image reconstruction is not needed in the therapy set-up verification, thus reducing computational time and artefacts. In addition, real time registration is feasible. Registration from partial projection data meets the geometry and dose requirements in many application cases and makes dynamic set-up verification possible in tomotherapy. (author)

  12. Collaborative Tracking of Image Features Based on Projective Invariance

    Science.gov (United States)

    Jiang, Jinwei

    -mode sensors for improving the flexibility and robustness of the system. From the experimental results during three field tests for the LASOIS system, we observed that most of the errors in the image processing algorithm are caused by the incorrect feature tracking. This dissertation addresses the feature tracking problem in image sequences acquired from cameras. Despite many alternatives to feature tracking problem, iterative least squares solution solving the optical flow equation has been the most popular approach used by many in the field. This dissertation attempts to leverage the former efforts to enhance feature tracking methods by introducing a view geometric constraint to the tracking problem, which provides collaboration among features. In contrast to alternative geometry based methods, the proposed approach provides an online solution to optical flow estimation in a collaborative fashion by exploiting Horn and Schunck flow estimation regularized by view geometric constraints. Proposed collaborative tracker estimates the motion of a feature based on the geometry of the scene and how the other features are moving. Alternative to this approach, a new closed form solution to tracking that combines the image appearance with the view geometry is also introduced. We particularly use invariants in the projective coordinates and conjecture that the traditional appearance solution can be significantly improved using view geometry. The geometric constraint is introduced by defining a new optical flow equation which exploits the scene geometry from a set drawn from tracked features. At the end of each tracking loop the quality of the tracked features is judged using both appearance similarity and geometric consistency. Our experiments demonstrate robust tracking performance even when the features are occluded or they undergo appearance changes due to projective deformation of the template. The proposed collaborative tracking method is also tested in the visual navigation

  13. Delta-projection imaging on contrast-enhanced ultrasound to quantify tumor microvasculature and perfusion.

    Science.gov (United States)

    Sehgal, Chandra M; Cary, Theodore W; Arger, Peter H; Wood, Andrew K W

    2009-01-01

    The aim of this study was to assess the Delta-projection image processing technique for visualizing tumor microvessels and for quantifying the area of tissue perfused by them on contrast-enhanced ultrasound images. The Delta-projection algorithm was implemented to quantify perfusion by tracking the running maximum of the difference (Delta) between the contrast-enhanced ultrasound image sequence and a baseline image. Twenty-five mice with subcutaneous K1735 melanomas were first imaged with contrast-enhanced grayscale and then with minimum-exposure contrast-enhanced power Doppler (minexCPD) ultrasound. Delta-projection images were reconstructed from the grayscale images and then used to evaluate the evolution of tumor vascularity during the course of contrast enhancement. The extent of vascularity (ratio of the perfused area to the tumor area) for each tumor was determined quantitatively from Delta-projection images and compared to the extent of vascularity determined from contrast-enhanced power Doppler images. Delta-projection and minexCPD measurements were compared using linear regression analysis. Delta-projection was successfully performed in all 25 cases. The technique allowed the dynamic visualization of individual blood vessels as they filled in real time. Individual tumor blood vessels were distinctly visible during early image enhancement. Later, as an increasing number of blood vessels were filled with the contrast agent, clusters of vessels appeared as regions of perfusion, and the identification of individual vessels became difficult. Comparisons were made between the perfused area of tumors in Delta-projections and in minexCPD images. The Delta-projection perfusion measurements were correlated linearly with minexCPD. Delta-projection visualized tumor vessels and enabled the quantitative assessment of the tumor area perfused by the contrast agent.

  14. From whole-body counting to imaging: The computer aided collimation gamma camera project (CACAO)

    International Nuclear Information System (INIS)

    Jeanguillaume, C.; Begot, S.; Quartuccio, M.; Douiri, A.; Ballongue, P.

    2000-01-01

    Whole-body counting is the method of choice for in vivo detection of contamination. To extend this well established method, the possible advantages of imaging radiocontaminants are examined. The use of the CACAO project is then studied. A comparison of simulated reconstructed images obtained by the CACAO project and by a conventional gamma camera used in nuclear medicine follows. Imaging a radionuclide contaminant with a geometrical sensitivity of 10 -2 seems possible in the near future. (author)

  15. Projecting Benevolent Power: Transforming America’s Image from Superpower to Superhero

    Science.gov (United States)

    2010-03-01

    St ra te gy R es ea rc h Pr oj ec t PROJECTING BENEVOLENT POWER: TRANSFORMING AMERICA’S IMAGE FROM SUPERPOWER TO SUPERHERO BY COLONEL...AND SUBTITLE Projecting Benevolent Power: Transforming America’s Image from Superpower to Superhero 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM... SUPERHERO by Colonel Kenneth D’Alfonso United States Air Force Dr. Craig Nation Project Adviser This SRP is

  16. EUV Doppler Imaging for CubeSat Platforms Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Mature the design and fabricate the Flare Initiation Doppler Imager (FIDI) instrument to demonstrate low-spacecraft-resource EUV technology (most notably,...

  17. Intelligent and interactive computer image of a nuclear power plant: The ImagIn project

    International Nuclear Information System (INIS)

    Haubensack, D.; Malvache, P.; Valleix, P.

    1998-01-01

    The ImagIn project consists in a method and a set of computer tools apt to bring perceptible and assessable improvements in the operational safety of a nuclear plant. Its aim is to design an information system that would maintain a highly detailed computerized representation of a nuclear plant in its initial state and throughout its in-service life. It is not a tool to drive or help driving the nuclear plant, but a tool that manages concurrent operations that modify the plant configuration in a very general was (maintenance for example). The configuration of the plant, as well as rules and constraints about it, are described in a object-oriented knowledge database, which is built using a generic ImagIn meta-model based on the semantical network theory. An inference engine works on this database and is connected to reality through interfaces to operators and captors on the installation; it verifies constantly in real-time the consistency of the database according to its inner rules, and reports eventual problems to concerned operators. A special effort is made on interfaces to provide natural and intuitive tools (using virtual reality, natural language, voice recognition and synthesis). A laboratory application on a fictive but realistic installation already exists and is used to simulate various tests and scenarii. A real application is being constructed on Siloe, an experimental reactor of the CEA. (author)

  18. Adaptive fringe-pattern projection for image saturation avoidance in 3D surface-shape measurement.

    Science.gov (United States)

    Li, Dong; Kofman, Jonathan

    2014-04-21

    In fringe-projection 3D surface-shape measurement, image saturation results in incorrect intensities in captured images of fringe patterns, leading to phase and measurement errors. An adaptive fringe-pattern projection (AFPP) method was developed to adapt the maximum input gray level in projected fringe patterns to the local reflectivity of an object surface being measured. The AFPP method demonstrated improved 3D measurement accuracy by avoiding image saturation in highly-reflective surface regions while maintaining high intensity modulation across the entire surface. The AFPP method can avoid image saturation and handle varying surface reflectivity, using only two prior rounds of fringe-pattern projection and image capture to generate the adapted fringe patterns.

  19. Research interface for experimental ultrasound imaging - the CFU grabber project

    DEFF Research Database (Denmark)

    Pedersen, Mads Møller; Hemmsen, Martin Christian; Jensen, Jørgen Arendt

    PC aquires pre processed data from the scanner in real time. Further post processing is required to create the final images. In house software (CFU Grabber tool) was developed to review and store the pre processed data. Using MatLab image processing with a new post post processing method the final...

  20. Fluorescence guided lymph node biopsy in large animals using direct image projection device

    Science.gov (United States)

    Ringhausen, Elizabeth; Wang, Tylon; Pitts, Jonathan; Akers, Walter J.

    2016-03-01

    The use of fluorescence imaging for aiding oncologic surgery is a fast growing field in biomedical imaging, revolutionizing open and minimally invasive surgery practices. We have designed, constructed, and tested a system for fluorescence image acquisition and direct display on the surgical field for fluorescence guided surgery. The system uses a near-infrared sensitive CMOS camera for image acquisition, a near-infra LED light source for excitation, and DLP digital projector for projection of fluorescence image data onto the operating field in real time. Instrument control was implemented in Matlab for image capture, processing of acquired data and alignment of image parameters with the projected pattern. Accuracy of alignment was evaluated statistically to demonstrate sensitivity to small objects and alignment throughout the imaging field. After verification of accurate alignment, feasibility for clinical application was demonstrated in large animal models of sentinel lymph node biopsy. Indocyanine green was injected subcutaneously in Yorkshire pigs at various locations to model sentinel lymph node biopsy in gynecologic cancers, head and neck cancer, and melanoma. Fluorescence was detected by the camera system during operations and projected onto the imaging field, accurately identifying tissues containing the fluorescent tracer at up to 15 frames per second. Fluorescence information was projected as binary green regions after thresholding and denoising raw intensity data. Promising results with this initial clinical scale prototype provided encouraging results for the feasibility of optical projection of acquired luminescence during open oncologic surgeries.

  1. Kernel based subspace projection of near infrared hyperspectral images of maize kernels

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Arngren, Morten; Hansen, Per Waaben

    2009-01-01

    In this paper we present an exploratory analysis of hyper- spectral 900-1700 nm images of maize kernels. The imaging device is a line scanning hyper spectral camera using a broadband NIR illumi- nation. In order to explore the hyperspectral data we compare a series of subspace projection methods...... including principal component analysis and maximum autocorrelation factor analysis. The latter utilizes the fact that interesting phenomena in images exhibit spatial autocorrelation. However, linear projections often fail to grasp the underlying variability on the data. Therefore we propose to use so......- tor transform outperform the linear methods as well as kernel principal components in producing interesting projections of the data....

  2. CT Image Reconstruction from Sparse Projections Using Adaptive TpV Regularization

    Directory of Open Access Journals (Sweden)

    Hongliang Qi

    2015-01-01

    Full Text Available Radiation dose reduction without losing CT image quality has been an increasing concern. Reducing the number of X-ray projections to reconstruct CT images, which is also called sparse-projection reconstruction, can potentially avoid excessive dose delivered to patients in CT examination. To overcome the disadvantages of total variation (TV minimization method, in this work we introduce a novel adaptive TpV regularization into sparse-projection image reconstruction and use FISTA technique to accelerate iterative convergence. The numerical experiments demonstrate that the proposed method suppresses noise and artifacts more efficiently, and preserves structure information better than other existing reconstruction methods.

  3. Optimized image acquisition for breast tomosynthesis in projection and reconstruction space

    International Nuclear Information System (INIS)

    Chawla, Amarpreet S.; Lo, Joseph Y.; Baker, Jay A.; Samei, Ehsan

    2009-01-01

    Breast tomosynthesis has been an exciting new development in the field of breast imaging. While the diagnostic improvement via tomosynthesis is notable, the full potential of tomosynthesis has not yet been realized. This may be attributed to the dependency of the diagnostic quality of tomosynthesis on multiple variables, each of which needs to be optimized. Those include dose, number of angular projections, and the total angular span of those projections. In this study, the authors investigated the effects of these acquisition parameters on the overall diagnostic image quality of breast tomosynthesis in both the projection and reconstruction space. Five mastectomy specimens were imaged using a prototype tomosynthesis system. 25 angular projections of each specimen were acquired at 6.2 times typical single-view clinical dose level. Images at lower dose levels were then simulated using a noise modification routine. Each projection image was supplemented with 84 simulated 3 mm 3D lesions embedded at the center of 84 nonoverlapping ROIs. The projection images were then reconstructed using a filtered backprojection algorithm at different combinations of acquisition parameters to investigate which of the many possible combinations maximizes the performance. Performance was evaluated in terms of a Laguerre-Gauss channelized Hotelling observer model-based measure of lesion detectability. The analysis was also performed without reconstruction by combining the model results from projection images using Bayesian decision fusion algorithm. The effect of acquisition parameters on projection images and reconstructed slices were then compared to derive an optimization rule for tomosynthesis. The results indicated that projection images yield comparable but higher performance than reconstructed images. Both modes, however, offered similar trends: Performance improved with an increase in the total acquisition dose level and the angular span. Using a constant dose level and angular

  4. Recent advances and future projections in clinical radionuclide imaging

    International Nuclear Information System (INIS)

    Peters, A.M.

    1990-01-01

    This outline review of recent advances in radionuclide imaging draws attention to developments in nuclear medicine of the urinary tract such as Captopril renography and the introduction of MAG-3, the technetium-99m labelled mimic of hippuran, the use of radionuclides for infection diagnosis, advances in lung perfusion scanning, new radiopharmaceuticals for cardiac imaging, and developments in radiopharmaceuticals for imaging tumours, including gallium-67, thallium-201, and the development of radiolabelled monoclonal antibodies. Attention is drawn to the wider use of nuclear medicine in child care. (author)

  5. Recent advances and future projections in clinical radionuclide imaging

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.M. (Royal Postgraduate Medical School, London (UK))

    1990-06-01

    This outline review of recent advances in radionuclide imaging draws attention to developments in nuclear medicine of the urinary tract such as Captopril renography and the introduction of MAG-3, the technetium-99m labelled mimic of hippuran, the use of radionuclides for infection diagnosis, advances in lung perfusion scanning, new radiopharmaceuticals for cardiac imaging, and developments in radiopharmaceuticals for imaging tumours, including gallium-67, thallium-201, and the development of radiolabelled monoclonal antibodies. Attention is drawn to the wider use of nuclear medicine in child care. (author).

  6. Pre-analytic process control: projecting a quality image.

    Science.gov (United States)

    Serafin, Mark D

    2006-09-26

    Within the health-care system, the term "ancillary department" often describes the laboratory. Thus, laboratories may find it difficult to define their image and with it, customer perception of department quality. Regulatory requirements give laboratories who so desire an elegant way to address image and perception issues--a comprehensive pre-analytic system solution. Since large laboratories use such systems--laboratory service manuals--I describe and illustrate the process for the benefit of smaller facilities. There exist resources to help even small laboratories produce a professional service manual--an elegant solution to image and customer perception of quality.

  7. Applied noncentral Chi-squared distribution in CFAR detection of hyperspectral projected images

    Science.gov (United States)

    Li, Zhiyong; Chen, Dong; Shi, Gongtao; Yang, Guopeng; Wang, Gang

    2015-10-01

    In this paper, the noncentral chi-squared distribution is applied in the Constant False Alarm Rate (CFAR) detection of hyperspectral projected images to distinguish the anomaly points from background. Usually, the process of the hyperspectral anomaly detectors can be considered as a linear projection. These operators are linear transforms and their results are quadratic form which comes from the transform of spectral vector. In general, chi-squared distribution could be the proper choice to describe the statistical characteristic of this projected image. However, because of the strong correlation among the bands, the standard central chi-squared distribution often cannot fit the stochastic characteristic of the projected images precisely. In this paper, we use a noncentral chi-squared distribution to approximate the projected image of subspace based anomaly detectors. Firstly, the statistical modal of the projected multivariate data is analysed, and a noncentral chi-squared distribution is deduced. Then, the approach of the parameters calculation is introduced. At last, the aerial hyperspectral images are used to verify the effectiveness of the proposed method in tightly modeling the projected image statistic distribution.

  8. High Resolution, Range/Range-Rate Imager Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Visidyne proposes to develop a design for a small, lightweight, high resolution, in x, y, and z Doppler imager to assist in the guidance, navigation and control...

  9. Rapid Acquisition Imaging Spectrograph (RAISE) Renewal Proposal Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The optical design of RAISE is based on a new class of UV/EUV imaging spectrometers that use  only two reflections to provide quasi-stigmatic performance...

  10. Low-Mass Planar Photonic Imaging Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a revolutionary electro-optical (EO) imaging sensor concept that provides a low-mass, low-volume alternative to the traditional bulky optical telescope...

  11. Gamma-Ray Imager Polarimeter for Solar Flares Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose here to develop the Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS), the next-generation instrument for high-energy solar observations. GRIPS will...

  12. Using Heliospheric Imager Data to Improve Space Weather Forecasting Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this project is to test a new approach for selecting the optimal solar wind model from an ensemble of model runs.Because of the paucity of...

  13. Enhanced Reliability MEMS Deformable Mirrors for Space Imaging Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this project is to develop and demonstrate a reliable, fault-tolerant wavefront control system that will fill a critical technology gap in NASA's vision...

  14. A portable image overlay projection device for computer-aided open liver surgery.

    Science.gov (United States)

    Gavaghan, Kate A; Peterhans, Matthias; Oliveira-Santos, Thiago; Weber, Stefan

    2011-06-01

    Image overlay projection is a form of augmented reality that allows surgeons to view underlying anatomical structures directly on the patient surface. It improves intuitiveness of computer-aided surgery by removing the need for sight diversion between the patient and a display screen and has been reported to assist in 3-D understanding of anatomical structures and the identification of target and critical structures. Challenges in the development of image overlay technologies for surgery remain in the projection setup. Calibration, patient registration, view direction, and projection obstruction remain unsolved limitations to image overlay techniques. In this paper, we propose a novel, portable, and handheld-navigated image overlay device based on miniature laser projection technology that allows images of 3-D patient-specific models to be projected directly onto the organ surface intraoperatively without the need for intrusive hardware around the surgical site. The device can be integrated into a navigation system, thereby exploiting existing patient registration and model generation solutions. The position of the device is tracked by the navigation system's position sensor and used to project geometrically correct images from any position within the workspace of the navigation system. The projector was calibrated using modified camera calibration techniques and images for projection are rendered using a virtual camera defined by the projectors extrinsic parameters. Verification of the device's projection accuracy concluded a mean projection error of 1.3 mm. Visibility testing of the projection performed on pig liver tissue found the device suitable for the display of anatomical structures on the organ surface. The feasibility of use within the surgical workflow was assessed during open liver surgery. We show that the device could be quickly and unobtrusively deployed within the sterile environment.

  15. THE IMAGE REGISTRATION OF FOURIER-MELLIN BASED ON THE COMBINATION OF PROJECTION AND GRADIENT PREPROCESSING

    Directory of Open Access Journals (Sweden)

    D. Gao

    2017-09-01

    Full Text Available Image registration is one of the most important applications in the field of image processing. The method of Fourier Merlin transform, which has the advantages of high precision and good robustness to change in light and shade, partial blocking, noise influence and so on, is widely used. However, not only this method can’t obtain the unique mutual power pulse function for non-parallel image pairs, even part of image pairs also can’t get the mutual power function pulse. In this paper, an image registration method based on Fourier-Mellin transformation in the view of projection-gradient preprocessing is proposed. According to the projection conformational equation, the method calculates the matrix of image projection transformation to correct the tilt image; then, gradient preprocessing and Fourier-Mellin transformation are performed on the corrected image to obtain the registration parameters. Eventually, the experiment results show that the method makes the image registration of Fourier-Mellin transformation not only applicable to the registration of the parallel image pairs, but also to the registration of non-parallel image pairs. What’s more, the better registration effect can be obtained

  16. The Image Registration of Fourier-Mellin Based on the Combination of Projection and Gradient Preprocessing

    Science.gov (United States)

    Gao, D.; Zhao, X.; Pan, X.

    2017-09-01

    Image registration is one of the most important applications in the field of image processing. The method of Fourier Merlin transform, which has the advantages of high precision and good robustness to change in light and shade, partial blocking, noise influence and so on, is widely used. However, not only this method can't obtain the unique mutual power pulse function for non-parallel image pairs, even part of image pairs also can't get the mutual power function pulse. In this paper, an image registration method based on Fourier-Mellin transformation in the view of projection-gradient preprocessing is proposed. According to the projection conformational equation, the method calculates the matrix of image projection transformation to correct the tilt image; then, gradient preprocessing and Fourier-Mellin transformation are performed on the corrected image to obtain the registration parameters. Eventually, the experiment results show that the method makes the image registration of Fourier-Mellin transformation not only applicable to the registration of the parallel image pairs, but also to the registration of non-parallel image pairs. What's more, the better registration effect can be obtained

  17. Radon transform based automatic metal artefacts generation for 3D threat image projection

    Science.gov (United States)

    Megherbi, Najla; Breckon, Toby P.; Flitton, Greg T.; Mouton, Andre

    2013-10-01

    Threat Image Projection (TIP) plays an important role in aviation security. In order to evaluate human security screeners in determining threats, TIP systems project images of realistic threat items into the images of the passenger baggage being scanned. In this proof of concept paper, we propose a 3D TIP method which can be integrated within new 3D Computed Tomography (CT) screening systems. In order to make the threat items appear as if they were genuinely located in the scanned bag, appropriate CT metal artefacts are generated in the resulting TIP images according to the scan orientation, the passenger bag content and the material of the inserted threat items. This process is performed in the projection domain using a novel methodology based on the Radon Transform. The obtained results using challenging 3D CT baggage images are very promising in terms of plausibility and realism.

  18. Multidisciplinary Collaboration and the Development of Multimedia Resources: The Images for Teaching Education Project.

    Science.gov (United States)

    Dillon, Patrick; Coupland, Jon; Edwards, Tony; Hudson, Alison; Tearle, Penni

    1998-01-01

    Describes the management of the University of Exeter (England) Images for Teaching Education Project, the design and use of educational materials, the production and use of images and sound, and the evaluation of teaching and learning. Discusses processes and outcomes of collaboration and the importance of a multidisciplinary approach. (PEN)

  19. Image restoration by the method of convex projections: part 2 applications and numerical results.

    Science.gov (United States)

    Sezan, M I; Stark, H

    1982-01-01

    The image restoration theory discussed in a previous paper by Youla and Webb [1] is applied to a simulated image and the results compared with the well-known method known as the Gerchberg-Papoulis algorithm. The results show that the method of image restoration by projection onto convex sets, by providing a convenient technique for utilizing a priori information, performs significantly better than the Gerchberg-Papoulis method.

  20. Traumatic Brain Injury Diffusion Magnetic Resonance Imaging Research Roadmap Development Project

    Science.gov (United States)

    2012-10-01

    optical imaging methods, PET/SPECT with radioisotope agents, and other technologies are less generally available or have known limitations. No “one...Brain Injury D-MRI Research Roadmap Development Project. Product Line Review (PLR) meeting, Medical Imaging Technologies. 12 June 2012. 11. Xia...meeting, Medical Imaging Technologies. Presentation slides. 12 June 2012. 1 Product Line Traumatic Brain Injury Diffusion Magnetic Resonance

  1. A projection graphic display for the computer aided analysis of bubble chamber images

    International Nuclear Information System (INIS)

    Solomos, E.

    1979-01-01

    A projection graphic display for aiding the analysis of bubble chamber photographs has been developed by the Instrumentation Group of EF Division at CERN. The display image is generated on a very high brightness cathode ray tube and projected on to the table of the scanning-measuring machines as a superposition to the image of the bubble chamber. The display can send messages to the operator and aid the measurement by indicating directly on the chamber image the tracks which are measured correctly or not. (orig.)

  2. Research on binary CT image reconstruction of steel tube section from three projections

    International Nuclear Information System (INIS)

    Peng Shuaijun; Wu Zhifang

    2008-01-01

    Fast online inspection technology is a difficult problem in the manufacture of steel tube. Radiographic CT imaging technology can reconstruct the image of steel tube section and acquire its most dimension parameters, which is quite appropriate for its inspection and quality control. A scan mode with immobile ray sources and detectors is proposed to reduce the inspection time. It can obtain projection data quickly and meet the need of online inspection. Maximum a posteriori (MAP) reconstruction algorithm is modified based on the space domain and pixel value domain characters of steel tube sections in order to reconstruct its image from few projections. The results of simulation experiment indicate that the modified MAP algorithm can reconstruct the image of steel tube section from at least three projections. The precision of acquired dimension parameters meets the requirement of national standard and the technology is expected to be widely used in practice. (authors)

  3. Projection domain denoising method based on dictionary learning for low-dose CT image reconstruction.

    Science.gov (United States)

    Zhang, Haiyan; Zhang, Liyi; Sun, Yunshan; Zhang, Jingyu

    2015-01-01

    Reducing X-ray tube current is one of the widely used methods for decreasing the radiation dose. Unfortunately, the signal-to-noise ratio (SNR) of the projection data degrades simultaneously. To improve the quality of reconstructed images, a dictionary learning based penalized weighted least-squares (PWLS) approach is proposed for sinogram denoising. The weighted least-squares considers the statistical characteristic of noise and the penalty models the sparsity of sinogram based on dictionary learning. Then reconstruct CT image using filtered back projection (FBP) algorithm from the denoised sinogram. The proposed method is particularly suitable for the projection data with low SNR. Experimental results show that the proposed method can get high-quality CT images when the signal to noise ratio of projection data declines sharply.

  4. Design and Development of a New Multi-Projection X-Ray System for Chest Imaging

    Science.gov (United States)

    Chawla, Amarpreet S.; Boyce, Sarah; Washington, Lacey; McAdams, H. Page; Samei, Ehsan

    2009-02-01

    Overlapping anatomical structures may confound the detection of abnormal pathology, including lung nodules, in conventional single-projection chest radiography. To minimize this fundamental limiting factor, a dedicated digital multi-projection system for chest imaging was recently developed at the Radiology Department of Duke University. We are reporting the design of the multi-projection imaging system and its initial performance in an ongoing clinical trial. The system is capable of acquiring multiple full-field projections of the same patient along both the horizontal and vertical axes at variable speeds and acquisition frame rates. These images acquired in rapid succession from slightly different angles about the posterior-anterior (PA) orientation can be correlated to minimize the influence of overlying anatomy. The developed system has been tested for repeatability and motion blur artifacts to investigate its robustness for clinical trials. Excellent geometrical consistency was found in the tube motion, with positional errors for clinical settings within 1%. The effect of tube-motion on the image quality measured in terms of impact on the modulation transfer function (MTF) was found to be minimal. The system was deemed clinic-ready and a clinical trial was subsequently launched. The flexibility of image acquisition built into the system provides a unique opportunity to easily modify it for different clinical applications, including tomosynthesis, correlation imaging (CI), and stereoscopic imaging.

  5. Augmented reality-guided neurosurgery: accuracy and intraoperative application of an image projection technique.

    Science.gov (United States)

    Besharati Tabrizi, Leila; Mahvash, Mehran

    2015-07-01

    An augmented reality system has been developed for image-guided neurosurgery to project images with regions of interest onto the patient's head, skull, or brain surface in real time. The aim of this study was to evaluate system accuracy and to perform the first intraoperative application. Images of segmented brain tumors in different localizations and sizes were created in 10 cases and were projected to a head phantom using a video projector. Registration was performed using 5 fiducial markers. After each registration, the distance of the 5 fiducial markers from the visualized tumor borders was measured on the virtual image and on the phantom. The difference was considered a projection error. Moreover, the image projection technique was intraoperatively applied in 5 patients and was compared with a standard navigation system. Augmented reality visualization of the tumors succeeded in all cases. The mean time for registration was 3.8 minutes (range 2-7 minutes). The mean projection error was 0.8 ± 0.25 mm. There were no significant differences in accuracy according to the localization and size of the tumor. Clinical feasibility and reliability of the augmented reality system could be proved intraoperatively in 5 patients (projection error 1.2 ± 0.54 mm). The augmented reality system is accurate and reliable for the intraoperative projection of images to the head, skull, and brain surface. The ergonomic advantage of this technique improves the planning of neurosurgical procedures and enables the surgeon to use direct visualization for image-guided neurosurgery.

  6. WE-G-BRF-04: Robust Real-Time Volumetric Imaging Based On One Single Projection

    International Nuclear Information System (INIS)

    Xu, Y; Yan, H; Ouyang, L; Wang, J; Jiang, S; Jia, X; Zhou, L

    2014-01-01

    Purpose: Real-time volumetric imaging is highly desirable to provide instantaneous image guidance for lung radiation therapy. This study proposes a scheme to achieve this goal using one single projection by utilizing sparse learning and a principal component analysis (PCA) based lung motion model. Methods: A patient-specific PCA-based lung motion model is first constructed by analyzing deformable vector fields (DVFs) between a reference image and 4DCT images at each phase. At the training stage, we “learn” the relationship between the DVFs and the projection using sparse learning. Specifically, we first partition the projections into patches, and then apply sparse learning to automatically identify patches that best correlate with the principal components of the DVFs. Once the relationship is established, at the application stage, we first employ a patchbased intensity correction method to overcome the problem of different intensity scale between the calculated projection in the training stage and the measured projection in the application stage. The corrected projection image is then fed to the trained model to derive a DVF, which is applied to the reference image, yielding a volumetric image corresponding to the projection. We have validated our method through a NCAT phantom simulation case and one experiment case. Results: Sparse learning can automatically select those patches containing motion information, such as those around diaphragm. For the simulation case, over 98% of the lung region pass the generalized gamma test (10HU/1mm), indicating combined accuracy in both intensity and spatial domain. For the experimental case, the average tumor localization errors projected to the imager are 0.68 mm and 0.4 mm on the axial and tangential direction, respectively. Conclusion: The proposed method is capable of accurately generating a volumetric image using one single projection. It will potentially offer real-time volumetric image guidance to facilitate lung

  7. Image reconstruction for digital breast tomosynthesis (DBT) by using projection-angle-dependent filter functions

    International Nuclear Information System (INIS)

    Park, Yeonok; Park, Chulkyu; Cho, Hyosung; Je, Uikyu; Hong, Daeki; Lee, Minsik; Cho, Heemoon; Choi, Sungil; Koo, Yangseo

    2014-01-01

    Digital breast tomosynthesis (DBT) is considered in clinics as a standard three-dimensional imaging modality, allowing the earlier detection of cancer. It typically acquires only 10-30 projections over a limited angle range of 15 - 60 .deg. with a stationary detector and typically uses a computationally-efficient filtered-backprojection (FBP) algorithm for image reconstruction. However, a common FBP algorithm yields poor image quality resulting from the loss of average image value and the presence of severe image artifacts due to the elimination of the dc component of the image by the ramp filter and to the incomplete data, respectively. As an alternative, iterative reconstruction methods are often used in DBT to overcome these difficulties, even though they are still computationally expensive. In this study, as a compromise, we considered a projection-angle dependent filtering method in which one-dimensional geometry-adapted filter kernels are computed with the aid of a conjugate-gradient method and are incorporated into the standard FBP framework. We implemented the proposed algorithm and performed systematic simulation works to investigate the imaging characteristics. Our results indicate that the proposed method is superior to a conventional FBP method for DBT imaging and has a comparable computational cost, while preserving good image homogeneity and edge sharpening with no serious image artifacts.

  8. Image reconstruction for digital breast tomosynthesis (DBT) by using projection-angle-dependent filter functions

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yeonok; Park, Chulkyu; Cho, Hyosung; Je, Uikyu; Hong, Daeki; Lee, Minsik; Cho, Heemoon; Choi, Sungil; Koo, Yangseo [Yonsei University, Wonju (Korea, Republic of)

    2014-09-15

    Digital breast tomosynthesis (DBT) is considered in clinics as a standard three-dimensional imaging modality, allowing the earlier detection of cancer. It typically acquires only 10-30 projections over a limited angle range of 15 - 60 .deg. with a stationary detector and typically uses a computationally-efficient filtered-backprojection (FBP) algorithm for image reconstruction. However, a common FBP algorithm yields poor image quality resulting from the loss of average image value and the presence of severe image artifacts due to the elimination of the dc component of the image by the ramp filter and to the incomplete data, respectively. As an alternative, iterative reconstruction methods are often used in DBT to overcome these difficulties, even though they are still computationally expensive. In this study, as a compromise, we considered a projection-angle dependent filtering method in which one-dimensional geometry-adapted filter kernels are computed with the aid of a conjugate-gradient method and are incorporated into the standard FBP framework. We implemented the proposed algorithm and performed systematic simulation works to investigate the imaging characteristics. Our results indicate that the proposed method is superior to a conventional FBP method for DBT imaging and has a comparable computational cost, while preserving good image homogeneity and edge sharpening with no serious image artifacts.

  9. Coalescence measurements for evolving foams monitored by real-time projection imaging

    International Nuclear Information System (INIS)

    Myagotin, A; Helfen, L; Baumbach, T

    2009-01-01

    Real-time radiographic projection imaging together with novel spatio-temporal image analysis is presented to be a powerful technique for the quantitative analysis of coalescence processes accompanying the generation and temporal evolution of foams and emulsions. Coalescence events can be identified as discontinuities in a spatio-temporal image representing a sequence of projection images. Detection, identification of intensity and localization of the discontinuities exploit a violation criterion of the Fourier shift theorem and are based on recursive spatio-temporal image partitioning. The proposed method is suited for automated measurements of discontinuity rates (i.e., discontinuity intensity per unit time), so that large series of radiographs can be analyzed without user intervention. The application potential is demonstrated by the quantification of coalescence during the formation and decay of metal foams monitored by real-time x-ray radiography

  10. Computerized mass detection for digital breast tomosynthesis directly from the projection images

    International Nuclear Information System (INIS)

    Reiser, I.; Nishikawa, R.M.; Giger, M.L.; Wu, T.; Rafferty, E.A.; Moore, R.; Kopans, D.B.

    2006-01-01

    Digital breast tomosynthesis (DBT) has recently emerged as a new and promising three-dimensional modality in breast imaging. In DBT, the breast volume is reconstructed from 11 projection images, taken at source angles equally spaced over an arc of 50 degrees. Reconstruction algorithms for this modality are not fully optimized yet. Because computerized lesion detection in the reconstructed breast volume will be affected by the reconstruction technique, we are developing a novel mass detection algorithm that operates instead on the set of raw projection images. Mass detection is done in three stages. First, lesion candidates are obtained for each projection image separately, using a mass detection algorithm that was initially developed for screen-film mammography. Second, the locations of a lesion candidate are backprojected into the breast volume. In this feature volume, voxel intensities are a combined measure of detection frequency (e.g., the number of projections in which a given lesion candidate was detected), and a measure of the angular range over which a given lesion was detected. Third, features are extracted after reprojecting the three-dimensional (3-D) locations of lesion candidates into projection images. Features are combined using linear discriminant analysis. The database used to test the algorithm consisted of 21 mass cases (13 malignant, 8 benign) and 15 cases without mass lesions. Based on this database, the algorithm yielded a sensitivity of 90% at 1.5 false positives per breast volume. Algorithm performance is positively biased because this dataset was used for development, training, and testing, and because the number of algorithm parameters was approximately the same as the number of patient cases. Our results indicate that computerized mass detection in the sequence of projection images for DBT may be effective despite the higher noise level in those images

  11. Fluorescence In Situ Hybridization (FISH Signal Analysis Using Automated Generated Projection Images

    Directory of Open Access Journals (Sweden)

    Xingwei Wang

    2012-01-01

    Full Text Available Fluorescence in situ hybridization (FISH tests provide promising molecular imaging biomarkers to more accurately and reliably detect and diagnose cancers and genetic disorders. Since current manual FISH signal analysis is low-efficient and inconsistent, which limits its clinical utility, developing automated FISH image scanning systems and computer-aided detection (CAD schemes has been attracting research interests. To acquire high-resolution FISH images in a multi-spectral scanning mode, a huge amount of image data with the stack of the multiple three-dimensional (3-D image slices is generated from a single specimen. Automated preprocessing these scanned images to eliminate the non-useful and redundant data is important to make the automated FISH tests acceptable in clinical applications. In this study, a dual-detector fluorescence image scanning system was applied to scan four specimen slides with FISH-probed chromosome X. A CAD scheme was developed to detect analyzable interphase cells and map the multiple imaging slices recorded FISH-probed signals into the 2-D projection images. CAD scheme was then applied to each projection image to detect analyzable interphase cells using an adaptive multiple-threshold algorithm, identify FISH-probed signals using a top-hat transform, and compute the ratios between the normal and abnormal cells. To assess CAD performance, the FISH-probed signals were also independently visually detected by an observer. The Kappa coefficients for agreement between CAD and observer ranged from 0.69 to 1.0 in detecting/counting FISH signal spots in four testing samples. The study demonstrated the feasibility of automated FISH signal analysis that applying a CAD scheme to the automated generated 2-D projection images.

  12. An accelerated threshold-based back-projection algorithm for Compton camera image reconstruction

    International Nuclear Information System (INIS)

    Mundy, Daniel W.; Herman, Michael G.

    2011-01-01

    Purpose: Compton camera imaging (CCI) systems are currently under investigation for radiotherapy dose reconstruction and verification. The ability of such a system to provide real-time images during dose delivery will be limited by the computational speed of the image reconstruction algorithm. In this work, the authors present a fast and simple method by which to generate an initial back-projected image from acquired CCI data, suitable for use in a filtered back-projection algorithm or as a starting point for iterative reconstruction algorithms, and compare its performance to the current state of the art. Methods: Each detector event in a CCI system describes a conical surface that includes the true point of origin of the detected photon. Numerical image reconstruction algorithms require, as a first step, the back-projection of each of these conical surfaces into an image space. The algorithm presented here first generates a solution matrix for each slice of the image space by solving the intersection of the conical surface with the image plane. Each element of the solution matrix is proportional to the distance of the corresponding voxel from the true intersection curve. A threshold function was developed to extract those pixels sufficiently close to the true intersection to generate a binary intersection curve. This process is repeated for each image plane for each CCI detector event, resulting in a three-dimensional back-projection image. The performance of this algorithm was tested against a marching algorithm known for speed and accuracy. Results: The threshold-based algorithm was found to be approximately four times faster than the current state of the art with minimal deficit to image quality, arising from the fact that a generically applicable threshold function cannot provide perfect results in all situations. The algorithm fails to extract a complete intersection curve in image slices near the detector surface for detector event cones having axes nearly

  13. Deuteron injector for Peking University Neutron Imaging Facility project

    Energy Technology Data Exchange (ETDEWEB)

    Ren, H. T.; Chen, J. E. [Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); SKLNPT, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Peng, S. X.; Lu, P. N.; Zhou, Q. F.; Yuan, Z. X.; Zhao, J.; Zhang, M.; Song, Z. Z.; Yu, J. X.; Guo, Z. Y. [SKLNPT, Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China)

    2012-02-15

    The deuteron injector developed for the PKUNIFTY (Peking University Neutron Imaging Facility) has been installed and commissioned at Peking University (PKU). The injector system must transfer 50 keV 50 mA of D{sup +} ion beam to the entrance of the 2 MeV radio frequency quadrupole (RFQ) with 10% duty factor (1 ms, 100 Hz). A compact 2.45 GHz permanent magnet electron cyclotron resonance (PMECR) ion source and a 1.36 m long low energy beam transport (LEBT) line using two solenoids was developed as the deuteron injector. A {phi}5 mm four-quadrant diaphragm was used to simulate the entrance of RFQ electrodes. The beam parameters are measured after this core with an emittance measurement unit (EMU) and a bending magnet for ion fraction analysis at the end of injector. During the commissioning, 77 mA of total deuteron beam was extracted from PMECR and 56 mA of pure D{sup +} beam that passed through the {phi}5 mm four-quadrant diaphragm was obtained at the position of RFQ entrance with the measured normalized rms emittance 0.12-0.16{pi} mm mrad. Ion species analysis results show that the deuteron fraction is as high as 99.5%. All of the parameters satisfy PKUNIFTY's requirements. In this paper, we will describe the deuteron injector design and report the commissioning results as well as the initial operation.

  14. JPEG2000-coded image error concealment exploiting convex sets projections.

    Science.gov (United States)

    Atzori, Luigi; Ginesu, Giaime; Raccis, Alessio

    2005-04-01

    Transmission errors in JPEG2000 can be grouped into three main classes, depending on the affected area: LL, high frequencies at the lower decomposition levels, and high frequencies at the higher decomposition levels. The first type of errors are the most annoying but can be concealed exploiting the signal spatial correlation like in a number of techniques proposed in the past; the second are less annoying but more difficult to address; the latter are often imperceptible. In this paper, we address the problem of concealing the second class or errors when high bit-planes are damaged by proposing a new approach based on the theory of projections onto convex sets. Accordingly, the error effects are masked by iteratively applying two procedures: low-pass (LP) filtering in the spatial domain and restoration of the uncorrupted wavelet coefficients in the transform domain. It has been observed that a uniform LP filtering brought to some undesired side effects that negatively compensated the advantages. This problem has been overcome by applying an adaptive solution, which exploits an edge map to choose the optimal filter mask size. Simulation results demonstrated the efficiency of the proposed approach.

  15. Comparison of polar formatting and back-projection algorithms for spotlight-mode SAR image formation

    Science.gov (United States)

    Jakowatz, Charles V., Jr.; Doren, Neall

    2006-05-01

    The convolution/back-projection (CBP) algorithm has recently once again been touted as the "gold standard" for spotlight-mode SAR image formation, as it is proclaimed to achieve better image quality than the well-known and often employed polar formatting algorithm (PFA). In addition, it has been suggested that PFA is less flexible than CBP in that PFA can only compute the SAR image on one grid and PFA cannot add or subtract pulses from the imaging process. The argument for CBP acknowledges the computational burden of CBP compared to PFA, but asserts that the increased image accuracy and flexibility of the formation process is warranted, at least in some imaging scenarios. Because CBP can now be sped up by the proper algorithm design, it becomes, according to this line of analysis, the clear algorithm of choice for SAR image formation. In this paper we reject the above conclusion by showing that PFA and CBP achieve the same image quality, and that PFA has complete flexibility, including choice of imaging plane, size of illuminated beam area to be imaged, resolution of the image, and others. We demonstrate these claims via formation of both simulated and real SAR imagery using both algorithms.

  16. Projection correction for the pixel-by-pixel basis in diffraction enhanced imaging

    International Nuclear Information System (INIS)

    Huang Zhifeng; Kang Kejun; Li Zheng

    2006-01-01

    Theories and methods of x-ray diffraction enhanced imaging (DEI) and computed tomography of the DEI (DEI-CT) have been investigated recently. But the phenomenon of projection offsets which may affect the accuracy of the results of extraction methods of refraction-angle images and reconstruction algorithms of the DEI-CT is seldom of concern. This paper focuses on it. Projection offsets are revealed distinctly according to the equivalent rectilinear propagation model of the DEI. Then, an effective correction method using the equivalent positions of projection data is presented to eliminate the errors induced by projection offsets. The correction method is validated by a computer simulation experiment and extraction methods or reconstruction algorithms based on the corrected data can give more accurate results. The limitations of the correction method are discussed at the end

  17. Tomographic mammography using a limited number of low-dose cone-beam projection images

    International Nuclear Information System (INIS)

    Wu Tao; Stewart, Alexander; Stanton, Martin; McCauley, Thomas; Phillips, Walter; Kopans, Daniel B.; Moore, Richard H.; Eberhard, Jeffrey W.; Opsahl-Ong, Beale; Niklason, Loren; Williams, Mark B.

    2003-01-01

    A method is described for using a limited number (typically 10-50) of low-dose radiographs to reconstruct the three-dimensional (3D) distribution of x-ray attenuation in the breast. The method uses x-ray cone-beam imaging, an electronic digital detector, and constrained nonlinear iterative computational techniques. Images are reconstructed with high resolution in two dimensions and lower resolution in the third dimension. The 3D distribution of attenuation that is projected into one image in conventional mammography can be separated into many layers (typically 30-80 1-mm-thick layers, depending on breast thickness), increasing the conspicuity of features that are often obscured by overlapping structure in a single-projection view. Schemes that record breast images at nonuniform angular increments, nonuniform image exposure, and nonuniform detector resolution are investigated in order to reduce the total x-ray exposure necessary to obtain diagnostically useful 3D reconstructions, and to improve the quality of the reconstructed images for a given exposure. The total patient radiation dose can be comparable to that used for a standard two-view mammogram. The method is illustrated with images from mastectomy specimens, a phantom, and human volunteers. The results show how image quality is affected by various data-collection protocols

  18. New Watermarking Scheme for Security and Transmission of Medical Images for PocketNeuro Project

    Directory of Open Access Journals (Sweden)

    M. S. Bouhlel

    2007-12-01

    Full Text Available We describe a new Watermarking system of medical information security and terminal mobile phone adaptation for PocketNeuro project. The later term refers to a Project created for the service of neurological diseases. It consists of transmitting information about patients "Desk of Patients" to a doctor's mobile phone when he is visiting or examining his patient. This system is capable of embedding medical information inside diagnostic images for security purposes. Our system applies JPEG Compression to Watermarked images to adapt them to the doctor's mobile phone. Experiments performed on a database of 30-256x256 pixel-sized neuronal images show that our Watermarking scheme for image security is robust against JPEG Compression. For the purpose of increasing the image Watermarking robustness against attacks for an image transmission and to perform a large data payload, we encode with Turbo-Code image-embedded bits information. Fidelity is improved by incorporation of the Relative Peak Signal-to-Noise Ratio (RPSNR as a perceptual metric to measure image degradation.

  19. Intensity-based bayesian framework for image reconstruction from sparse projection data

    International Nuclear Information System (INIS)

    Rashed, E.A.; Kudo, Hiroyuki

    2009-01-01

    This paper presents a Bayesian framework for iterative image reconstruction from projection data measured over a limited number of views. The classical Nyquist sampling rule yields the minimum number of projection views required for accurate reconstruction. However, challenges exist in many medical and industrial imaging applications in which the projection data is undersampled. Classical analytical reconstruction methods such as filtered backprojection (FBP) are not a good choice for use in such cases because the data undersampling in the angular range introduces aliasing and streak artifacts that degrade lesion detectability. In this paper, we propose a Bayesian framework for maximum likelihood-expectation maximization (ML-EM)-based iterative reconstruction methods that incorporates a priori knowledge obtained from expected intensity information. The proposed framework is based on the fact that, in tomographic imaging, it is often possible to expect a set of intensity values of the reconstructed object with relatively high accuracy. The image reconstruction cost function is modified to include the l 1 norm distance to the a priori known information. The proposed method has the potential to regularize the solution to reduce artifacts without missing lesions that cannot be expected from the a priori information. Numerical studies showed a significant improvement in image quality and lesion detectability under the condition of highly undersampled projection data. (author)

  20. Results Of The IMAGES Project 1986-1989; Facts And Fallacies

    Science.gov (United States)

    Ottes, Fenno P.; de Valk, Jan P.; Lodder, Herman; Stut, W. J.; van der Horst-Bruinsma, I.; Hofland, Paul L.; van Poppel, Bas M.; Ter Haar Romeny, Bart M.; Bakker, Albert R.

    1989-05-01

    A concise overview is presented on the results of the total IMAGIS (IMAGe Information System) research as carried out by BAZIS. This paper is intended as a continuation of the IMAGIS presentation at the 'Dutch PACS session' during the SPIE Medical Imaging H Conference 1988. That session was jointly organized by the Utrecht University Hospital (AZU), BAZIS and Philips Medical Systems, the partners within the Dutch PACS project. The HIS-PACS coupling/integration project has resulted in a HIS-PACS coupling that is used to transfer data from the BAZIS HIS to the prototype Philips PACS. The modelling and simulation project has resulted in a modelling and simulation package (MIRACLES), which has been used to suggest performance improvements of existing and future PACS's. To support the technology assessment project a PC program has been developed that calculates the financial consequences of the introduction of a PACS (CAPACITY). The diagnostic image quality evaluation project has provided research protocols and a software package (FEASIBLE) that have been used as an aid to execute observer performance studies. A software package (FRACTALS) has been developed so that a standard computer (113M RT PC) can be used as a simple image workstation for radiological research. Furthermore, a number of general issues concerning the development, the acceptance and the introduction of PACS are discussed.

  1. Reconstruction of tomographic image from x-ray projections of a few views

    International Nuclear Information System (INIS)

    Kobayashi, Fujio; Yamaguchi, Shoichiro

    1982-01-01

    Computer tomographs have progressed rapidly, and in the latest high performance types, the photographing time has been shortened to less than 5 sec, but the clear images of hearts have not yet been obtained. The X-ray tomographs used so far irradiate X-ray from many directions and measure the projected data, but by limiting projection direction to a small number, it was planned to shorter the X-ray photographing time and to reduce X-ray exposure as the objective of this study. In this paper, a method is proposed, by which tomographic images are reconstructed from projected data in a small number of direction by generalized inverse matrix penalty method. This method is the calculation method newly devised by the authors for this purpose. It is a kind of the nonlinear planning method added with the restrictive condition using a generalized inverse matrix, and it is characterized by the simple calculation procedure and rapid convergence. Moreover, the effect on reconstructed images when errors are included in projected data was examined. Also, the simple computer simulation to reconstruct tomographic images using the projected data in four directions was performed, and the usefulness of this method was confirmed. It contributes to the development of superhigh speed tomographs in future. (Kako, I.)

  2. Polarization Imaging Apparatus for Cell and Tissue Imaging and Diagnostics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This work proposes to capitalize on our Phase I success in a novel visible-near infrared Stokes polarization imaging technology based on high performance fast...

  3. Twin image removal in digital in-line holography based on iterative inter-projections

    Science.gov (United States)

    Chen, Bing Kuan; Chen, Tai-Yu; Hung, Shau Gang; Huang, Sheng-Lung; Lin, Jiunn-Yuan

    2016-06-01

    A simple and efficient phase retrieval method based on the iterative inter-projections of the recorded Fourier modulus between two effective holographic planes is developed to eliminate the twin image in digital in-line holography. The proposed algorithm converges stably in phase extraction procedures without requiring any prior knowledge or sophisticated support of the object and is applicable to lensless Gabor and Fourier holography as well as holographic microscopy with imaging lenses. Numerical and experimental results suggest that the spatial resolution enhancement on the reconstructed image can be achieved with this technique due to the capability of recovering the diffraction phases of low-intensity signals.

  4. Automatic content extraction of filled-form images based on clustering component block projection vectors

    Science.gov (United States)

    Peng, Hanchuan; He, Xiaofeng; Long, Fuhui

    2003-12-01

    Automatic understanding of document images is a hard problem. Here we consider a sub-problem, automatically extracting content from filled form images. Without pre-selected templates or sophisticated structural/semantic analysis, we propose a novel approach based on clustering the component-block-projection-vectors. By combining spectral clustering and minimal spanning tree clustering, we generate highly accurate clusters, from which the adaptive templates are constructed to extract the filled-in content. Our experiments show this approach is effective for a set of 1040 US IRS tax form images belonging to 208 types.

  5. Improvement of image quality of holographic projection on tilted plane using iterative algorithm

    Science.gov (United States)

    Pang, Hui; Cao, Axiu; Wang, Jiazhou; Zhang, Man; Deng, Qiling

    2017-12-01

    Holographic image projection on tilted plane has an important application prospect. In this paper, we propose a method to compute the phase-only hologram that can reconstruct a clear image on tilted plane. By adding a constant phase to the target image of the inclined plane, the corresponding light field distribution on the plane that is parallel to the hologram plane is derived through the titled diffraction calculation. Then the phase distribution of the hologram is obtained by the iterative algorithm with amplitude and phase constrain. Simulation and optical experiment are performed to show the effectiveness of the proposed method.

  6. EISCAT Aperture Synthesis Imaging (EASI _3D) for the EISCAT_3D Project

    Science.gov (United States)

    La Hoz, Cesar; Belyey, Vasyl

    2012-07-01

    Aperture Synthesis Imaging Radar (ASIR) is one of the technologies adopted by the EISCAT_3D project to endow it with imaging capabilities in 3-dimensions that includes sub-beam resolution. Complemented by pulse compression, it will provide 3-dimensional images of certain types of incoherent scatter radar targets resolved to about 100 metres at 100 km range, depending on the signal-to-noise ratio. This ability will open new research opportunities to map small structures associated with non-homogeneous, unstable processes such as aurora, summer and winter polar radar echoes (PMSE and PMWE), Natural Enhanced Ion Acoustic Lines (NEIALs), structures excited by HF ionospheric heating, meteors, space debris, and others. The underlying physico-mathematical principles of the technique are the same as the technique employed in radioastronomy to image stellar objects; both require sophisticated inversion techniques to obtain reliable images.

  7. Optical projection tomography via phase retrieval algorithms for hidden three dimensional imaging

    Science.gov (United States)

    Ancora, Daniele; Di Battista, Diego; Giasafaki, Georgia; Psycharakis, Stylianos; Liapis, Evangelos; Zacharopoulos, Athanasios; Zacharakis, Giannis

    2017-02-01

    Optical tomography in biomedical imaging is a highly dynamic field in which non-invasive optical and computational techniques are combined to obtain a three dimensional representation of the specimen we are interested to image. Although at optical wavelengths scattering is the main obstacle to reach diffraction limited resolution, recently several studies have shown the possibility to image even objects fully hidden behind a turbid layer exploiting the information contained in the speckle autocorrelation via an iterative phase retrieval algorithm. In this work we explore the possibility of blind three dimensional reconstruction approach based on the Optical Projection Tomography principles, a widely used tool to image almost transparent model organism such as C. Elegans and D. Rerio. By using autocorrelation information rather than projections at each angle we prove, both numerically and experimentally, the possibility to perform exact three dimensional reconstructions via a specifically designed phase retrieval algorithm, extending the capability of the projection-based tomographic methods to image behind scattering curtains. The reconstruction scheme we propose is simple to implement, does not require post-processing data alignment and moreover can be trivially implemented in parallel to fully exploit the computing power offered by modern GPUs, further reducing the need for costly computational resources.

  8. Direct image reconstruction with limited angle projection data for computerized tomography

    International Nuclear Information System (INIS)

    Inouye, T.

    1980-01-01

    Discussions are made on the minimum angle range for projection data necessary to reconstruct the complete CT image. As is easily shown from the image reconstruction theorem, the lack of projection angle provides no data for the Fourier transformed function of the object on the corresponding angular directions, where the projections are missing. In a normal situation, the Fourier transformed function of an object image holds an analytic characteristic with respect to two-dimensional orthogonal parameters. This characteristic enables uniquely prolonging the function outside the obtained region employing a sort of analytic continuation with respect to both parameters. In the method reported here, an object pattern, which is confined within a finite range, is shifted to a specified region to have complete orthogonal function expansions without changing the projection angle directions. These orthogonal functions are analytically extended to the missing projection angle range and the whole function is determined. This method does not include any estimation process, whose effectiveness is often seriously jeopardized by the presence of a slight fluctuation component. Computer simulations were carried out to demonstrate the effectiveness of the method

  9. Locality Preserving Projection Based on Endmember Extraction for Hyperspectral Image Dimensionality Reduction and Target Detection.

    Science.gov (United States)

    Wang, Yiting; Huang, Shiqi; Liu, Zhigang; Wang, Hongxia; Liu, Daizhi

    2016-09-01

    In order to reduce the effect of spectral variability on calculation precision for the weighted matrix in the locality preserving projection (LPP) algorithm, an improved dimensionality reduction method named endmember extraction-based locality preserving projection (EE-LPP) is proposed in this paper. The method primarily uses the vertex component analysis (VCA) method to extract endmember spectra from hyperspectral imagery. It then calculates the similarity between pixel spectra and the endmember spectra by using the spectral angle distance, and uses it as the basis for selecting neighboring pixels in the image and constructs a weighted matrix between pixels. Finally, based on the weighted matrix, the idea of the LPP algorithm is applied to reduce the dimensions of hyperspectral image data. Experimental results of real hyperspectral data demonstrate that the low-dimensional features acquired by the proposed methods can fully reflect the characteristics of the original image and further improve target detection accuracy. © The Author(s) 2016.

  10. Survey of on-road image projection with pixel light systems

    Science.gov (United States)

    Rizvi, Sadiq; Knöchelmann, Marvin; Ley, Peer-Phillip; Lachmayer, Roland

    2017-12-01

    HID, LED and laser-based high resolution automotive headlamps, as of late known as `pixel light systems', are at the forefront of the developing technologies paving the way for autonomous driving. In addition to light distribution capabilities that outperform Adaptive Front Lighting and Matrix Beam systems, pixel light systems provide the possibility of image projection directly onto the street. The underlying objective is to improve the driving experience, in any given scenario, in terms of safety, comfort and interaction for all road users. The focus of this work is to conduct a short survey on this state-of-the-art image projection functionality. A holistic research regarding the image projection functionality can be divided into three major categories: scenario selection, technological development and evaluation design. Consequently, the work presented in this paper is divided into three short studies. Section 1 provides a brief introduction to pixel light systems and a justification for the approach adopted for this study. Section 2 deals with the selection of scenarios (and driving maneuvers) where image projection can play a critical role. Section 3 discusses high power LED and LED array based prototypes that are currently under development. Section 4 demonstrates results from an experiment conducted to evaluate the illuminance of an image space projected using a pixel light system prototype developed at the Institute of Product Development (IPeG). Findings from this work can help to identify and advance future research work relating to: further development of pixel light systems, scenario planning, examination of optimal light sources, behavioral response studies etc.

  11. Fan-beam and cone-beam image reconstruction via filtering the backprojection image of differentiated projection data

    International Nuclear Information System (INIS)

    Zhuang Tingliang; Leng Shuai; Nett, Brian E; Chen Guanghong

    2004-01-01

    In this paper, a new image reconstruction scheme is presented based on Tuy's cone-beam inversion scheme and its fan-beam counterpart. It is demonstrated that Tuy's inversion scheme may be used to derive a new framework for fan-beam and cone-beam image reconstruction. In this new framework, images are reconstructed via filtering the backprojection image of differentiated projection data. The new framework is mathematically exact and is applicable to a general source trajectory provided the Tuy data sufficiency condition is satisfied. By choosing a piece-wise constant function for one of the components in the factorized weighting function, the filtering kernel is one dimensional, viz. the filtering process is along a straight line. Thus, the derived image reconstruction algorithm is mathematically exact and efficient. In the cone-beam case, the derived reconstruction algorithm is applicable to a large class of source trajectories where the pi-lines or the generalized pi-lines exist. In addition, the new reconstruction scheme survives the super-short scan mode in both the fan-beam and cone-beam cases provided the data are not transversely truncated. Numerical simulations were conducted to validate the new reconstruction scheme for the fan-beam case

  12. Block matching sparsity regularization-based image reconstruction for incomplete projection data in computed tomography

    Science.gov (United States)

    Cai, Ailong; Li, Lei; Zheng, Zhizhong; Zhang, Hanming; Wang, Linyuan; Hu, Guoen; Yan, Bin

    2018-02-01

    In medical imaging many conventional regularization methods, such as total variation or total generalized variation, impose strong prior assumptions which can only account for very limited classes of images. A more reasonable sparse representation frame for images is still badly needed. Visually understandable images contain meaningful patterns, and combinations or collections of these patterns can be utilized to form some sparse and redundant representations which promise to facilitate image reconstructions. In this work, we propose and study block matching sparsity regularization (BMSR) and devise an optimization program using BMSR for computed tomography (CT) image reconstruction for an incomplete projection set. The program is built as a constrained optimization, minimizing the L1-norm of the coefficients of the image in the transformed domain subject to data observation and positivity of the image itself. To solve the program efficiently, a practical method based on the proximal point algorithm is developed and analyzed. In order to accelerate the convergence rate, a practical strategy for tuning the BMSR parameter is proposed and applied. The experimental results for various settings, including real CT scanning, have verified the proposed reconstruction method showing promising capabilities over conventional regularization.

  13. Learning binary code via PCA of angle projection for image retrieval

    Science.gov (United States)

    Yang, Fumeng; Ye, Zhiqiang; Wei, Xueqi; Wu, Congzhong

    2018-01-01

    With benefits of low storage costs and high query speeds, binary code representation methods are widely researched for efficiently retrieving large-scale data. In image hashing method, learning hashing function to embed highdimensions feature to Hamming space is a key step for accuracy retrieval. Principal component analysis (PCA) technical is widely used in compact hashing methods, and most these hashing methods adopt PCA projection functions to project the original data into several dimensions of real values, and then each of these projected dimensions is quantized into one bit by thresholding. The variances of different projected dimensions are different, and with real-valued projection produced more quantization error. To avoid the real-valued projection with large quantization error, in this paper we proposed to use Cosine similarity projection for each dimensions, the angle projection can keep the original structure and more compact with the Cosine-valued. We used our method combined the ITQ hashing algorithm, and the extensive experiments on the public CIFAR-10 and Caltech-256 datasets validate the effectiveness of the proposed method.

  14. A method for volumetric imaging in radiotherapy using single x-ray projection

    International Nuclear Information System (INIS)

    Xu, Yuan; Yan, Hao; Ouyang, Luo; Wang, Jing; Jiang, Steve B.; Jia, Xun; Zhou, Linghong; Cervino, Laura

    2015-01-01

    Purpose: It is an intriguing problem to generate an instantaneous volumetric image based on the corresponding x-ray projection. The purpose of this study is to develop a new method to achieve this goal via a sparse learning approach. Methods: To extract motion information hidden in projection images, the authors partitioned a projection image into small rectangular patches. The authors utilized a sparse learning method to automatically select patches that have a high correlation with principal component analysis (PCA) coefficients of a lung motion model. A model that maps the patch intensity to the PCA coefficients was built along with the patch selection process. Based on this model, a measured projection can be used to predict the PCA coefficients, which are then further used to generate a motion vector field and hence a volumetric image. The authors have also proposed an intensity baseline correction method based on the partitioned projection, in which the first and the second moments of pixel intensities at a patch in a simulated projection image are matched with those in a measured one via a linear transformation. The proposed method has been validated in both simulated data and real phantom data. Results: The algorithm is able to identify patches that contain relevant motion information such as the diaphragm region. It is found that an intensity baseline correction step is important to remove the systematic error in the motion prediction. For the simulation case, the sparse learning model reduced the prediction error for the first PCA coefficient to 5%, compared to the 10% error when sparse learning was not used, and the 95th percentile error for the predicted motion vector was reduced from 2.40 to 0.92 mm. In the phantom case with a regular tumor motion, the predicted tumor trajectory was successfully reconstructed with a 0.82 mm error for tumor center localization compared to a 1.66 mm error without using the sparse learning method. When the tumor motion

  15. Calibration, Projection, and Final Image Products of MESSENGER's Mercury Dual Imaging System

    Science.gov (United States)

    Denevi, Brett W.; Chabot, Nancy L.; Murchie, Scott L.; Becker, Kris J.; Blewett, David T.; Domingue, Deborah L.; Ernst, Carolyn M.; Hash, Christopher D.; Hawkins, S. Edward; Keller, Mary R.; Laslo, Nori R.; Nair, Hari; Robinson, Mark S.; Seelos, Frank P.; Stephens, Grant K.; Turner, F. Scott; Solomon, Sean C.

    2018-02-01

    We present an overview of the operations, calibration, geodetic control, photometric standardization, and processing of images from the Mercury Dual Imaging System (MDIS) acquired during the orbital phase of the MESSENGER spacecraft's mission at Mercury (18 March 2011-30 April 2015). We also provide a summary of all of the MDIS products that are available in NASA's Planetary Data System (PDS). Updates to the radiometric calibration included slight modification of the frame-transfer smear correction, updates to the flat fields of some wide-angle camera (WAC) filters, a new model for the temperature dependence of narrow-angle camera (NAC) and WAC sensitivity, and an empirical correction for temporal changes in WAC responsivity. Further, efforts to characterize scattered light in the WAC system are described, along with a mosaic-dependent correction for scattered light that was derived for two regional mosaics. Updates to the geometric calibration focused on the focal lengths and distortions of the NAC and all WAC filters, NAC-WAC alignment, and calibration of the MDIS pivot angle and base. Additionally, two control networks were derived so that the majority of MDIS images can be co-registered with sub-pixel accuracy; the larger of the two control networks was also used to create a global digital elevation model. Finally, we describe the image processing and photometric standardization parameters used in the creation of the MDIS advanced products in the PDS, which include seven large-scale mosaics, numerous targeted local mosaics, and a set of digital elevation models ranging in scale from local to global.

  16. Development of an image reconstruction algorithm for a few number of projection data

    International Nuclear Information System (INIS)

    Vieira, Wilson S.; Brandao, Luiz E.; Braz, Delson

    2007-01-01

    An image reconstruction algorithm was developed for specific cases of radiotracer applications in industry (rotating cylindrical mixers), involving a very few number of projection data. The algorithm was planned for imaging radioactive isotope distributions around the center of circular planes. The method consists of adapting the original expectation maximization algorithm (EM) to solve the ill-posed emission tomography inverse problem in order to reconstruct transversal 2D images of an object with only four projections. To achieve this aim, counts of photons emitted by selected radioactive sources in the plane, after they had been simulated using the commercial software MICROSHIELD 5.05, constitutes the projections and a computational code (SPECTEM) was developed to generate activity vectors or images related to those sources. SPECTEM is flexible to support simultaneous changes of the detectors's geometry, the medium under investigation and the properties of the gamma radiation. As a consequence of the code had been followed correctly the proposed method, good results were obtained and they encouraged us to continue the next step of the research: the validation of SPECTEM utilizing experimental data to check its real performance. We aim this code will improve considerably radiotracer methodology, making easier the diagnosis of fails in industrial processes. (author)

  17. Development of an image reconstruction algorithm for a few number of projection data

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Wilson S.; Brandao, Luiz E. [Instituto de Engenharia Nuclear (IEN-CNEN/RJ), Rio de Janeiro , RJ (Brazil)]. E-mails: wilson@ien.gov.br; brandao@ien.gov.br; Braz, Delson [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programa de Pos-graduacao de Engenharia (COPPE). Lab. de Instrumentacao Nuclear]. E-mail: delson@mailhost.lin.ufrj.br

    2007-07-01

    An image reconstruction algorithm was developed for specific cases of radiotracer applications in industry (rotating cylindrical mixers), involving a very few number of projection data. The algorithm was planned for imaging radioactive isotope distributions around the center of circular planes. The method consists of adapting the original expectation maximization algorithm (EM) to solve the ill-posed emission tomography inverse problem in order to reconstruct transversal 2D images of an object with only four projections. To achieve this aim, counts of photons emitted by selected radioactive sources in the plane, after they had been simulated using the commercial software MICROSHIELD 5.05, constitutes the projections and a computational code (SPECTEM) was developed to generate activity vectors or images related to those sources. SPECTEM is flexible to support simultaneous changes of the detectors's geometry, the medium under investigation and the properties of the gamma radiation. As a consequence of the code had been followed correctly the proposed method, good results were obtained and they encouraged us to continue the next step of the research: the validation of SPECTEM utilizing experimental data to check its real performance. We aim this code will improve considerably radiotracer methodology, making easier the diagnosis of fails in industrial processes. (author)

  18. Project Blue: Optical Coronagraphic Imaging Search for Terrestrial-class Exoplanets in Alpha Centauri

    Science.gov (United States)

    Morse, Jon; Project Blue team

    2018-01-01

    Project Blue is a coronagraphic imaging space telescope mission designed to search for habitable worlds orbiting the nearest Sun-like stars in the Alpha Centauri system. With a 45-50 cm baseline primary mirror size, Project Blue will perform a reconnaissance of the habitable zones of Alpha Centauri A and B in blue light and one or two longer wavelength bands to determine the hue of any planets discovered. Light passing through the off-axis telescope feeds into a coronagraphic instrument that forms the heart of the mission. Various coronagraph designs are being considered, such as phase induced amplitude apodization (PIAA), vector vortex, etc. Differential orbital image processing techniques will be employed to analyze the data for faint planets embedded in the residual glare of the parent star. Project Blue will advance our knowledge about the presence or absence of terrestrial-class exoplanets in the habitable zones and measure the brightness of zodiacal dust around each star, which will aid future missions in planning their observational surveys of exoplanets. It also provides on-orbit demonstration of high-contrast coronagraphic imaging technologies and techniques that will be useful for planning and implementing future space missions by NASA and other space agencies. We present an overview of the science goals, mission concept and development schedule. As part of our cooperative agreement with NASA, the Project Blue team intends to make the data available in a publicly accessible archive.

  19. Benchtop and Animal Validation of a Projective Imaging System for Potential Use in Intraoperative Surgical Guidance.

    Science.gov (United States)

    Gan, Qi; Wang, Dong; Ye, Jian; Zhang, Zeshu; Wang, Xinrui; Hu, Chuanzhen; Shao, Pengfei; Xu, Ronald X

    2016-01-01

    We propose a projective navigation system for fluorescence imaging and image display in a natural mode of visual perception. The system consists of an excitation light source, a monochromatic charge coupled device (CCD) camera, a host computer, a projector, a proximity sensor and a Complementary metal-oxide-semiconductor (CMOS) camera. With perspective transformation and calibration, our surgical navigation system is able to achieve an overall imaging speed higher than 60 frames per second, with a latency of 330 ms, a spatial sensitivity better than 0.5 mm in both vertical and horizontal directions, and a projection bias less than 1 mm. The technical feasibility of image-guided surgery is demonstrated in both agar-agar gel phantoms and an ex vivo chicken breast model embedding Indocyanine Green (ICG). The biological utility of the system is demonstrated in vivo in a classic model of ICG hepatic metabolism. Our benchtop, ex vivo and in vivo experiments demonstrate the clinical potential for intraoperative delineation of disease margin and image-guided resection surgery.

  20. A study on projection angles for an optimal image of PNS water's view on children

    International Nuclear Information System (INIS)

    Son, Sang Hyuk; Song, Young Geun; Kim, Sung Kyu; Hong, Sang Woo; Kim, Je Bong

    2007-01-01

    This study is to calculate the proper angle for the optimal image of PNS Water's view on children, comparing and analyzing the PNS Water's projection angles between children and adults at every age. This study randomly selected 50 patients who visited the Medical Center from January to May in 2005, and examined the incidence path of central ray, taking a PNS Water's and skull trans-Lat. view in Water's filming position while attaching a lead ball mark on the Orbit, EAM, and acanthion of the patient's skull. And then, we calculated the incidence angles (angle A) of the line connected from OML and the petrous ridge to the inferior margin of maxilla on general (random) patient's skull image, following the incidence path of central ray. Finally, we analyzed two pieces of the graphs at ages, developing out the patient's ideal images at PNS Water's filming position taken by a digital camera, and calculating the angle (angle B) between OML and IP(Image Plate). The angle between OML and IP is about 43 .deg. in 4-years-old children, which is higher than 37 .deg. as age increases the angle decreases, it goes to 37 .deg. around 30 years of age. That is similar result to maxillary growth period. We can get better quality of Water's image for children when taking the PNS Water's view if we change the projection angles, considering maxillary growth for patients in every age stage

  1. Rigid motion correction of dual opposed planar projections in single photon imaging

    Science.gov (United States)

    Angelis, G. I.; Ryder, W. J.; Gillam, J. E.; Boisson, F.; Kyme, A. Z.; Fulton, R. R.; Meikle, S. R.; Kench, P. L.

    2017-05-01

    Awake and/or freely moving small animal single photon emission imaging allows the continuous study of molecules exhibiting slow kinetics without the need to restrain or anaesthetise the animals. Estimating motion free projections in freely moving small animal planar imaging can be considered as a limited angle tomography problem, except that we wish to estimate the 2D planar projections rather than the 3D volume, where the angular sampling in all three axes depends on the rotational motion of the animal. In this study, we hypothesise that the motion corrected planar projections estimated by reconstructing an estimate of the 3D volume using an iterative motion compensating reconstruction algorithm and integrating it along the projection path, will closely match the true, motion-less, planar distribution regardless of the object motion. We tested this hypothesis for the case of rigid motion using Monte-Carlo simulations and experimental phantom data based on a dual opposed detector system, where object motion was modelled with 6 degrees of freedom. In addition, we investigated the quantitative accuracy of the regional activity extracted from the geometric mean of opposing motion corrected planar projections. Results showed that it is feasible to estimate qualitatively accurate motion-corrected projections for a wide range of motions around all 3 axes. Errors in the geometric mean estimates of regional activity were relatively small and within 10% of expected true values. In addition, quantitative regional errors were dependent on the observed motion, as well as on the surrounding activity of overlapping organs. We conclude that both qualitatively and quantitatively accurate motion-free projections of the tracer distribution in a rigidly moving object can be estimated from dual opposed detectors using a correction approach within an iterative reconstruction framework and we expect this approach can be extended to the case of non-rigid motion.

  2. Neural network CT image reconstruction method for small amount of projection data

    International Nuclear Information System (INIS)

    Ma, X.F.; Fukuhara, M.; Takeda, T.

    2000-01-01

    This paper presents a new method for two-dimensional image reconstruction by using a multi-layer neural network. Though a conventionally used object function of such a neural network is composed of a sum of squared errors of the output data, we define an object function composed of a sum of squared residuals of an integral equation. By employing an appropriate numerical line integral for this integral equation, we can construct a neural network which can be used for CT image reconstruction for cases with small amount of projection data. We applied this method to some model problems and obtained satisfactory results. This method is especially useful for analyses of laboratory experiments or field observations where only a small amount of projection data is available in comparison with the well-developed medical applications

  3. Neural network CT image reconstruction method for small amount of projection data

    CERN Document Server

    Ma, X F; Takeda, T

    2000-01-01

    This paper presents a new method for two-dimensional image reconstruction by using a multi-layer neural network. Though a conventionally used object function of such a neural network is composed of a sum of squared errors of the output data, we define an object function composed of a sum of squared residuals of an integral equation. By employing an appropriate numerical line integral for this integral equation, we can construct a neural network which can be used for CT image reconstruction for cases with small amount of projection data. We applied this method to some model problems and obtained satisfactory results. This method is especially useful for analyses of laboratory experiments or field observations where only a small amount of projection data is available in comparison with the well-developed medical applications.

  4. Kinematic Measurement of Knee Prosthesis from Single-Plane Projection Images

    Science.gov (United States)

    Hirokawa, Shunji; Ariyoshi, Shogo; Takahashi, Kenji; Maruyama, Koichi

    In this paper, the measurement of 3D motion from 2D perspective projections of knee prosthesis is described. The technique reported by Banks and Hodge was further developed in this study. The estimation was performed in two steps. The first-step estimation was performed on the assumption of orthogonal projection. Then, the second-step estimation was subsequently carried out based upon the perspective projection to accomplish more accurate estimation. The simulation results have demonstrated that the technique archived sufficient accuracies of position/orientation estimation for prosthetic kinematics. Then we applied our algorithm to the CCD images, thereby examining the influences of various artifacts, possibly incorporated through an imaging process, on the estimation accuracies. We found that accuracies in the experiment were influenced mainly by the geometric discrepancies between the prosthesis component and computer generated model and by the spacial inconsistencies between the coordinate axes of the positioner and that of the computer model. However, we verified that our algorithm could achieve proper and consistent estimation even for the CCD images.

  5. THE USE OF PUBLIC RELATIONS IN PROJECTING AN ORGANIZATION'S POSITIVE IMAGE

    Directory of Open Access Journals (Sweden)

    Ioana Olariu

    2017-07-01

    Full Text Available This article is a theoretical approach on the importance of using public relations in helping an organization to project a positive image. The study of the impact information has on the image of organisations seems to be an interesting research topic. Practice has proved that the image of institutions has a patrimonial value and it is sometimes essential in raising their credibility. It can be said that an image is defined as the representation of certain attitudes, opinions or prejudices concerning a person, a group of persons or the public opinion concerning an institution. In other words, an image is the opinion of a person, of a group of persons or of the public opinion regarding that institution. All specialists agree that a negative image affects, sometimes to an incredible extent, the success of an institution. In the contemporary age, we cannot speak about public opinion without taking into consideration the mass media as a main agent in transmitting the information to the public, with unlimited possibilities of influencing or forming it. The plan for the PR department starts with its own declaration of principles, which describes its roles and contribution to the organisation.

  6. Neural network algorithm for image reconstruction using the grid friendly projections

    International Nuclear Information System (INIS)

    Cierniak, R.

    2011-01-01

    Full text: The presented paper describes a development of original approach to the reconstruction problem using a recurrent neural network. Particularly, the 'grid-friendly' angles of performed projections are selected according to the discrete Radon transform (DRT) concept to decrease the number of projections required. The methodology of our approach is consistent with analytical reconstruction algorithms. Reconstruction problem is reformulated in our approach to optimization problem. This problem is solved in present concept using method based on the maximum likelihood methodology. The reconstruction algorithm proposed in this work is consequently adapted for more practical discrete fan beam projections. Computer simulation results show that the neural network reconstruction algorithm designed to work in this way improves obtained results and outperforms conventional methods in reconstructed image quality. (author)

  7. Stereoscopic versus monoscopic detection of masses on breast tomosynthesis projection images

    Science.gov (United States)

    Muralidhar, Gautam S.; Ganapathi, Tejaswini; Bovik, Alan C.; Markey, Mia K.; Haygood, Tamara M.; Stephens, Tanya W.; Whitman, Gary J.

    2012-02-01

    The goal of this study was to assess if stereoscopic viewing of breast tomosynthesis projection images impacted mass detection performance when compared to monoscopic viewing. The dataset for this study, provided by Hologic, Inc., contained 47 craniocaudal cases (23 biopsy proven malignant masses and 24 normals). Two projection images that were separated by 8 degrees were chosen to form a stereoscopic pair. The images were preprocessed to enhance their contrast and were presented on a stereoscopic display. Three experienced breast imagers participated in a blinded observer study as readers. Each case was shown twice to each reader - once in the stereoscopic mode, and once in the monoscopic mode in a random order. The readers were asked to make a binary decision on whether they saw a mass for which they would initiate a diagnostic workup or not, and also report the location of the mass and provide a confidence score in the range of 0-100. The binary decisions were analyzed using the sensitivity-specificity measure, while the confidence scores were analyzed using the Receiver Operating Characteristic curve (ROC). We also report a statistical analysis of the difference in partial AUC values greater than 95% sensitivity between the stereoscopic and monoscopic modes.

  8. The Ilac-Project Supporting Ancient Coin Classification by Means of Image Analysis

    Science.gov (United States)

    Kavelar, A.; Zambanini, S.; Kampel, M.; Vondrovec, K.; Siegl, K.

    2013-07-01

    This paper presents the ILAC project, which aims at the development of an automated image-based classification system for ancient Roman Republican coins. The benefits of such a system are manifold: operating at the suture between computer vision and numismatics, ILAC can reduce the day-to-day workload of numismatists by assisting them in classification tasks and providing a preselection of suitable coin classes. This is especially helpful for large coin hoard findings comprising several thousands of coins. Furthermore, this system could be implemented in an online platform for hobby numismatists, allowing them to access background information about their coin collection by simply uploading a photo of obverse and reverse for the coin of interest. ILAC explores different computer vision techniques and their combinations for the use of image-based coin recognition. Some of these methods, such as image matching, use the entire coin image in the classification process, while symbol or legend recognition exploit certain characteristics of the coin imagery. An overview of the methods explored so far and the respective experiments is given as well as an outlook on the next steps of the project.

  9. THE ILAC-PROJECT: SUPPORTING ANCIENT COIN CLASSIFICATION BY MEANS OF IMAGE ANALYSIS

    Directory of Open Access Journals (Sweden)

    A. Kavelar

    2013-07-01

    Full Text Available This paper presents the ILAC project, which aims at the development of an automated image-based classification system for ancient Roman Republican coins. The benefits of such a system are manifold: operating at the suture between computer vision and numismatics, ILAC can reduce the day-to-day workload of numismatists by assisting them in classification tasks and providing a preselection of suitable coin classes. This is especially helpful for large coin hoard findings comprising several thousands of coins. Furthermore, this system could be implemented in an online platform for hobby numismatists, allowing them to access background information about their coin collection by simply uploading a photo of obverse and reverse for the coin of interest. ILAC explores different computer vision techniques and their combinations for the use of image-based coin recognition. Some of these methods, such as image matching, use the entire coin image in the classification process, while symbol or legend recognition exploit certain characteristics of the coin imagery. An overview of the methods explored so far and the respective experiments is given as well as an outlook on the next steps of the project.

  10. The Salton Seismic Imaging Project (SSIP): Rift Processes and Earthquake Hazards in the Salton Trough (Invited)

    Science.gov (United States)

    Hole, J. A.; Stock, J. M.; Fuis, G. S.; Rymer, M. J.; Murphy, J. M.; Sickler, R. R.; Criley, C. J.; Goldman, M.; Catchings, R. D.; Ricketts, J. W.; Gonzalez-Fernandez, A.; Driscoll, N.; Kent, G.; Harding, A. J.; Klemperer, S. L.

    2009-12-01

    The Salton Seismic Imaging Project (SSIP) and coordinated projects will acquire seismic data in and across the Salton Trough in southern California and northern Mexico, including the Coachella, Imperial, and Mexicali Valleys. These projects address both rifting processes at the northern end of the Gulf of California extensional province and earthquake hazards at the southern end of the San Andreas Fault system. In the central Salton Trough, North American lithosphere appears to have been rifted completely apart. Based primarily on a 1979 seismic refraction project, the 20-22 km thick crust is apparently composed entirely of new crust added by magmatism from below and sedimentation from above. The new data will constrain the style of continental breakup, the role and mode of magmatism, the effects of rapid Colorado River sedimentation upon extension and magmatism, and the partitioning of oblique extension. The southernmost San Andreas Fault is considered at high risk of producing a large damaging earthquake, yet structures of the fault and adjacent basins are poorly constrained. To improve hazard models, SSIP will image the geometry of the San Andreas and Imperial Faults, structure of sedimentary basins in the Salton Trough, and three-dimensional seismic velocity of the crust and uppermost mantle. SSIP and collaborating projects have been funded by several different programs at NSF and the USGS. These projects include seven lines of land refraction and low-fold reflection data, airguns and OBS data in the Salton Sea, coordinated fieldwork for onshore-offshore and 3-D data, and a densely sampled line of broadband stations across the trough. Fieldwork is tentatively scheduled for 2010. Preliminary work in 2009 included calibration shots in the Imperial Valley that quantified strong ground motion and proved lack of harm to agricultural irrigation tile drains from explosive shots. Piggyback and complementary studies are encouraged.

  11. New K-edge-balanced contrast phantom for image quality assurance in projection radiography

    Science.gov (United States)

    Cresens, Marc; Schaetzing, Ralph

    2003-06-01

    X-ray-absorber step-wedge phantoms serve in projection radiography to assess a detection system's overall exposure-related signal-to-noise ratio performance and contrast response. Data derived from a phantom image, created by exposing a step-wedge onto the image receptor, are compared with predefined acceptance criteria during periodic image quality assurance (QA). For contrast-related measurements, in particular, the x-ray tube potential requires accurate setting and low ripple, since small deviations from the specified kVp, causing energy spectrum changes, lead to significant image signal variation at high contrast ratios. A K-edge-balanced, rare-earth-metal contrast phantom can generate signals that are significantly more robust to the spectral variability and instability of exposure equipment in the field. The image signals from a hafnium wedge, for example, are up to eight times less sensitive to spectral fluctuations than those of today"s copper phantoms for a 200:1 signal ratio. At 120 kVp (RQA 9), the hafnium phantom still preserves 70% of the subject contrast present at 75 kVp (RQA 5). A copper wedge preserves only 7% of its contrast over the same spectral range. Spectral simulations and measurements on prototype systems, as well as potential uses of this new class of phantoms (e.g., QA, single-shot exposure response characterization) are described.

  12. Respiratory compensation in projection imaging using a magnification and displacement model

    International Nuclear Information System (INIS)

    Crawford, C.R.; King, K.F.; Ritchie, C.J.; Godwin, J.D.

    1996-01-01

    Respiratory motion during the collection of computed tomography (CT) projections generates structured artifacts and a loss of resolution that can render the scans unusable. This motion is problematic in scans of those patients who cannot suspend respiration, such as the very young or incubated patients. In this paper, the authors present an algorithm that can be used to reduce motion artifacts in CT scans caused by respiration. An approximate model for the effect of respiration is that the object cross section under interrogation experiences time-varying magnification and displacement along two axes. Using this model an exact filtered backprojection algorithm is derived for the case of parallel projections. The result is extended to generate an approximate reconstruction formula for fan-beam projections. Computer simulations and scans of phantoms on a commercial CT scanner validate the new reconstruction algorithms for parallel and fan-beam projections. Significant reduction in respiratory artifacts is demonstrated clinically when the motion model is satisfied. The method can be applied to projection data used in CT single photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance imaging (MRI)

  13. Methods of X-ray CT image reconstruction from few projections

    International Nuclear Information System (INIS)

    Wang, H.

    2011-01-01

    To improve the safety (low dose) and the productivity (fast acquisition) of a X-ray CT system, we want to reconstruct a high quality image from a small number of projections. The classical reconstruction algorithms generally fail since the reconstruction procedure is unstable and suffers from artifacts. A new approach based on the recently developed 'Compressed Sensing' (CS) theory assumes that the unknown image is in some sense 'sparse' or 'compressible', and the reconstruction is formulated through a non linear optimization problem (TV/l1 minimization) by enhancing the sparsity. Using the pixel (or voxel in 3D) as basis, to apply the CS framework in CT one usually needs a 'sparsifying' transform, and combines it with the 'X-ray projector' which applies on the pixel image. In this thesis, we have adapted a 'CT-friendly' radial basis of Gaussian family called 'blob' to the CS-CT framework. The blob has better space-frequency localization properties than the pixel, and many operations, such as the X-ray transform, can be evaluated analytically and are highly parallelizable (on GPU platform). Compared to the classical Kaisser-Bessel blob, the new basis has a multi-scale structure: an image is the sum of dilated and translated radial Mexican hat functions. The typical medical objects are compressible under this basis, so the sparse representation system used in the ordinary CS algorithms is no more needed. 2D simulations show that the existing TV and l1 algorithms are more efficient and the reconstructions have better visual quality than the equivalent approach based on the pixel or wavelet basis. The new approach has also been validated on 2D experimental data, where we have observed that in general the number of projections can be reduced to about 50%, without compromising the image quality. (author) [fr

  14. Simulations of Aperture Synthesis Imaging Radar for the EISCAT_3D Project

    Science.gov (United States)

    La Hoz, C.; Belyey, V.

    2012-12-01

    EISCAT_3D is a project to build the next generation of incoherent scatter radars endowed with multiple 3-dimensional capabilities that will replace the current EISCAT radars in Northern Scandinavia. Aperture Synthesis Imaging Radar (ASIR) is one of the technologies adopted by the EISCAT_3D project to endow it with imaging capabilities in 3-dimensions that includes sub-beam resolution. Complemented by pulse compression, it will provide 3-dimensional images of certain types of incoherent scatter radar targets resolved to about 100 metres at 100 km range, depending on the signal-to-noise ratio. This ability will open new research opportunities to map small structures associated with non-homogeneous, unstable processes such as aurora, summer and winter polar radar echoes (PMSE and PMWE), Natural Enhanced Ion Acoustic Lines (NEIALs), structures excited by HF ionospheric heating, meteors, space debris, and others. To demonstrate the feasibility of the antenna configurations and the imaging inversion algorithms a simulation of synthetic incoherent scattering data has been performed. The simulation algorithm incorporates the ability to control the background plasma parameters with non-homogeneous, non-stationary components over an extended 3-dimensional space. Control over the positions of a number of separated receiving antennas, their signal-to-noise-ratios and arriving phases allows realistic simulation of a multi-baseline interferometric imaging radar system. The resulting simulated data is fed into various inversion algorithms. This simulation package is a powerful tool to evaluate various antenna configurations and inversion algorithms. Results applied to realistic design alternatives of EISCAT_3D will be described.

  15. History, current activities and future direction of the IMAGE project the briefing book for the 3rd meeting of the Ad-hoc IMAGE Advisory Board

    NARCIS (Netherlands)

    Leemans R; MNV; CIM

    1999-01-01

    This report presents background material for the third meeting of the Ad-hoc IMAGE-2 Advisory Board. This Board reviews recent developments and applications and give advice on potential future directions of the IMAGE-related climate-change projects at RIVM. The aim of this report is to give an

  16. Processed infrared images of plastic and metallic landmines in an Argentine project

    Science.gov (United States)

    Castro, E. H.; Abbate, H. A.; Costanzo, M.; Mejail, M. E.; Gambini, J.; Jacobo Berlles, J. C.; Santos, J. M.; Borensztejn, P.

    2007-04-01

    A great development of technologies for the detection of buried landmines took place worldwide in the last years. In Argentina, a project for the development of an autonomous robot with sensors for landmines detection was recently approved by the Science and Technology National Agency. Within this project we are studying the detection of landmines by infrared radiation. Metallic and plastic objects with landmines shape and dimension were buried at different depths from 1 to 4 cm in soil and sand. Periodic natural warming by solar radiation or artificial warming by means of electric resistances or flash lamps were applied. Infrared images were obtained in the 8-12 micrometers spectral band with a microbolometer camera. The IR images were processed by different methods to obtain a definition as good as possible of the buried objects. After this a B-Spline method was applied to detect the targets contours and determine shape and dimensions of them so as to distinguish landmines from other objects. We are looking for a landmine detection method as simple and fast possible, with detection capability of metallic and plastic landmines and an acceptable false alarm rate which would be reduced when applied with other detection methods as GPR and electromagnetic induction. We present obtained and processed images and results obtained to distinguish buried landmines from other buried objects.

  17. The effect of compensating filter on image quality in lateral projection of thoraco lumbar radiography

    Science.gov (United States)

    Daud, N. A. A.; Ali, M. H.; Nazri, N. A. Ahmad; Hamzah, N. J.; Awang, N. A.

    2014-11-01

    The aim of this project was to study the effect of compensating filter on image quality in lateral projection of thoraco lumbar radiography. The specific objectives of this study were to verify the relationship between density, contrast and noise of lateral thoraco lumbar radiography using various thickness of compensating filter and to determine the appropriate filter thickness with the thoraco lumbar density. The study was performed by an X- ray unit exposed to the body phantom where different thicknesses of aluminium were used as compensating filter. The radiographs were processed by CR reader and being imported to KPACS software to analyze the pixel depth value, contrast and noise. Result shows different thickness of aluminium compensating filter improved the image quality of lateral projection thoraco lumbar radiography. The compensating filter of 8.2 mm was considered as the optimal filter to compensate the thoraco lumbar junction (T12-L1), 1 mm to compensate lumbar region and 5.9 mm to compensate thorax region. The addition of aluminium compensating filter is advantageous in terms of efficiency which saving radiograph film, workload of the radiographer and radiation dose to patient.

  18. ABrIL - Advanced Brain Imaging Lab : a cloud based computation environment for cooperative neuroimaging projects.

    Science.gov (United States)

    Neves Tafula, Sérgio M; Moreira da Silva, Nádia; Rozanski, Verena E; Silva Cunha, João Paulo

    2014-01-01

    Neuroscience is an increasingly multidisciplinary and highly cooperative field where neuroimaging plays an important role. Neuroimaging rapid evolution is demanding for a growing number of computing resources and skills that need to be put in place at every lab. Typically each group tries to setup their own servers and workstations to support their neuroimaging needs, having to learn from Operating System management to specific neuroscience software tools details before any results can be obtained from each setup. This setup and learning process is replicated in every lab, even if a strong collaboration among several groups is going on. In this paper we present a new cloud service model - Brain Imaging Application as a Service (BiAaaS) - and one of its implementation - Advanced Brain Imaging Lab (ABrIL) - in the form of an ubiquitous virtual desktop remote infrastructure that offers a set of neuroimaging computational services in an interactive neuroscientist-friendly graphical user interface (GUI). This remote desktop has been used for several multi-institution cooperative projects with different neuroscience objectives that already achieved important results, such as the contribution to a high impact paper published in the January issue of the Neuroimage journal. The ABrIL system has shown its applicability in several neuroscience projects with a relatively low-cost, promoting truly collaborative actions and speeding up project results and their clinical applicability.

  19. Engaging stakeholder communities as body image intervention partners: The Body Project as a case example.

    Science.gov (United States)

    Becker, Carolyn Black; Perez, Marisol; Kilpela, Lisa Smith; Diedrichs, Phillippa C; Trujillo, Eva; Stice, Eric

    2017-04-01

    Despite recent advances in developing evidence-based psychological interventions, substantial changes are needed in the current system of intervention delivery to impact mental health on a global scale (Kazdin & Blase, 2011). Prevention offers one avenue for reaching large populations because prevention interventions often are amenable to scaling-up strategies, such as task-shifting to lay providers, which further facilitate community stakeholder partnerships. This paper discusses the dissemination and implementation of the Body Project, an evidence-based body image prevention program, across 6 diverse stakeholder partnerships that span academic, non-profit and business sectors at national and international levels. The paper details key elements of the Body Project that facilitated partnership development, dissemination and implementation, including use of community-based participatory research methods and a blended train-the-trainer and task-shifting approach. We observed consistent themes across partnerships, including: sharing decision making with community partners, engaging of community leaders as gatekeepers, emphasizing strengths of community partners, working within the community's structure, optimizing non-traditional and/or private financial resources, placing value on cost-effectiveness and sustainability, marketing the program, and supporting flexibility and creativity in developing strategies for evolution within the community and in research. Ideally, lessons learned with the Body Project can be generalized to implementation of other body image and eating disorder prevention programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Low-complexity camera digital signal imaging for video document projection system

    Science.gov (United States)

    Hsia, Shih-Chang; Tsai, Po-Shien

    2011-04-01

    We present high-performance and low-complexity algorithms for real-time camera imaging applications. The main functions of the proposed camera digital signal processing (DSP) involve color interpolation, white balance, adaptive binary processing, auto gain control, and edge and color enhancement for video projection systems. A series of simulations demonstrate that the proposed method can achieve good image quality while keeping computation cost and memory requirements low. On the basis of the proposed algorithms, the cost-effective hardware core is developed using Verilog HDL. The prototype chip has been verified with one low-cost programmable device. The real-time camera system can achieve 1270 × 792 resolution with the combination of extra components and can demonstrate each DSP function.

  1. A new EU-funded project for enhanced real-time imaging for radiotherapy

    CERN Multimedia

    KTT Life Sciences Unit

    2011-01-01

    ENTERVISION (European training network for digital imaging for radiotherapy) is a new Marie Curie Initial Training Network coordinated by CERN, which brings together multidisciplinary researchers to carry out R&D in physics techniques for application in the clinical environment.   ENTERVISION was established in response to a critical need to reinforce research in online 3D digital imaging and to train professionals in order to deliver some of the key elements for early detection and more precise treatment of tumours. The main goal of the project is to train researchers who will help contribute to technical developments in an exciting multidisciplinary field, where expertise from physics, medicine, electronics, informatics, radiobiology and engineering merges and catalyses the advancement of cancer treatment. With this aim in mind, ENTERVISION brings together ten academic institutes and research centres, as well as the two leading European companies in particle therapy, IBA and Siemens. &ldq...

  2. Grid Databases for Shared Image Analysis in the MammoGrid Project

    CERN Document Server

    Amendolia, S R; Hauer, T; Manset, D; McClatchey, R; Odeh, M; Reading, T; Rogulin, D; Schottlander, D; Solomonides, T

    2004-01-01

    The MammoGrid project aims to prove that Grid infrastructures can be used for collaborative clinical analysis of database-resident but geographically distributed medical images. This requires: a) the provision of a clinician-facing front-end workstation and b) the ability to service real-world clinician queries across a distributed and federated database. The MammoGrid project will prove the viability of the Grid by harnessing its power to enable radiologists from geographically dispersed hospitals to share standardized mammograms, to compare diagnoses (with and without computer aided detection of tumours) and to perform sophisticated epidemiological studies across national boundaries. This paper outlines the approach taken in MammoGrid to seamlessly connect radiologist workstations across a Grid using an "information infrastructure" and a DICOM-compliant object model residing in multiple distributed data stores in Italy and the UK

  3. Effects of energy space smoothing and projection space normalization on multispectral PET image quality

    International Nuclear Information System (INIS)

    Yao, R.; Msaki, P.; Bentourkia, M.; Lecomte, R.

    1996-01-01

    Independent processing of multispectral positron emission tomography (MSPET) data in individual energy frames has the potential to improve system sensitivity and the accuracy of energy dependent scatter correction. However, statistical fluctuations due to the use of multiple energy windows and low system detection efficiency severely undermine this potential. These limitations have been overcome without resolution loss by smoothing data in the energy space to suppress statistical fluctuations and by normalizing detector efficiency in the spatial domain to minimize systematic errors. The effectiveness of these corrections was evaluated by comparing images acquired in different energy frames with and without energy space smoothing. Smoothing improved the sharpness and contrast and decreased noise of images. The FWHM and FWTM evaluated from line source images confirmed an earlier postulate which stated that smoothing in the energy space has no effect on image resolution since such process does not move counts across lines of response (LORs). It was concluded that smoothing in the energy space in conjunction with normalization in the projection space is a prerequisite for subsequent energy-dependent data processing such as scatter correction

  4. Improved superficial brain hemorrhage visualization in susceptibility weighted images by constrained minimum intensity projection

    Science.gov (United States)

    Castro, Marcelo A.; Pham, Dzung L.; Butman, John

    2016-03-01

    Minimum intensity projection is a technique commonly used to display magnetic resonance susceptibility weighted images, allowing the observer to better visualize hemorrhages and vasculature. The technique displays the minimum intensity in a given projection within a thick slab, allowing different connectivity patterns to be easily revealed. Unfortunately, the low signal intensity of the skull within the thick slab can mask superficial tissues near the skull base and other regions. Because superficial microhemorrhages are a common feature of traumatic brain injury, this effect limits the ability to proper diagnose and follow up patients. In order to overcome this limitation, we developed a method to allow minimum intensity projection to properly display superficial tissues adjacent to the skull. Our approach is based on two brain masks, the largest of which includes extracerebral voxels. The analysis of the rind within both masks containing the actual brain boundary allows reclassification of those voxels initially missed in the smaller mask. Morphological operations are applied to guarantee accuracy and topological correctness, and the mean intensity within the mask is assigned to all outer voxels. This prevents bone from dominating superficial regions in the projection, enabling superior visualization of cortical hemorrhages and vessels.

  5. Image restoration by the method of convex projections: part 1 theory.

    Science.gov (United States)

    Youla, D C; Webb, H

    1982-01-01

    A projection operator onto a closed convex set in Hilbert space is one of the few examples of a nonlinear map that can be defined in simple abstract terms. Moreover, it minimizes distance and is nonexpansive, and therefore shares two of the more important properties of ordinary linear orthogonal projections onto closed linear manifolds. In this paper, we exploit the properties of these operators to develop several iterative algorithms for image restoration from partial data which permit any number of nonlinear constraints of a certain type to be subsumed automatically. Their common conceptual basis is as follows. Every known property of an original image f is envisaged as restricting it to lie in a well-defined closed convex set. Thus, m such properties place f in the intersection E(0) = E(i) of the corresponding closed convex sets E(1),E(2),...EE(m). Given only the projection operators PE(i) onto the individual E(i)'s, i = 1 --> m, we restore f by recursive means. Clearly, in this approach, the realization of the P(i)'s in a Hilbert space setting is one of the major synthesis problems. Section I describes the geometrical significance of the three main theorems in considerable detail, and most of the underlying ideas are illustrated with the aid of simple diagrams. Section II presents rules for the numerical implementation of 11 specific projection operators which are found to occur frequently in many signal-processing applications, and the Appendix contains proofs of all the major results.

  6. Influence of the number of basis images and projection array on caries detection using tuned aperture computed tomography (TACT).

    Science.gov (United States)

    Abreu, M; Tyndall, D A; Ludlow, J B; Nortjé, C J

    2002-01-01

    to determine if the number of basis images and spatial distribution of the projection array used for TACT slice generation influence observer performance in caries detection. In the first experiment, 2, 4, 8 and 12 basis projections of each of 40 teeth were acquired using a CMOS digital radiography sensor. Projections were distributed radially in space using a 20 degree angular disparity. TACT slices were generated from the four subgroups of images, presented to eight observers, and viewed on a high-resolution monitor. Observers scored the presence/absence of caries using a 5-point confidence scale. Gold standard was histological examination of tooth sections. ROC curves measured observer diagnostic performance. ANOVA tested for significant differences between observers and experimental conditions. In the second experiment, the number of basis projections judged to be satisfactory for TACT slice generation was used. Horizontal and vertical linear arrays of projections were compared to the circular projection array. There was a statistically significant difference between the numbers of basis projections in the detection of both occlusal (P=0.006) and proximal caries (P=0.005). No significant difference was found between projection arrays in the detection of either occlusal (P=0.065) or proximal (P=0.515) caries. The number of TACT basis projections significantly influences caries detection. Eight or more images should be used. Either linear-vertical, linear-horizontal or circular arrays of basis projections may be used for TACT slice generation in caries detection tasks.

  7. Landsat Image Analysis of the Rebea Agricultural Project, Mosul Dam and Lake, Northern Iraq

    Science.gov (United States)

    Welsh, W.; Alassadi, F.

    2014-12-01

    An archive of 70 good-to-excellent quality Landsat TM and ETM+ images acquired between 1984 and 2011 were identified through visual examination of the GLOVIS web portal. After careful consideration of factors relevant to agriculture in the region (e.g., crop calendar) and associated image processing needs (e.g., preference for anniversary dates), the images deemed most appropriate were downloaded. Standard preprocessing, including visual quality and statistical inspection, sub-setting to the study area, was performed, and the results combined in a database with available GIS data. The resolution merge spatial enhancement technique was applied to any ETM+ imagery to improve visual clarity and interpretability. The NDVI was calculated for all images in the time series. Unsupervised classification of images was performed for dates ranging from 1987 just before the inception of the Rebea project in 1989 through 2011. In order to reduce uncertainty related to lack of detailed ancillary and/or ground reference data, simple land cover classes were mapped, specifically: surface water, agriculture, and other. Results were able to quantify and track areas of each class over time, and showed a marked decrease in agriculture between the Iraq invasion in 2003 to the end of the study period in 2011, despite massive efforts and capital by the United States and Iraqi governments to improve agriculture in the area. Complications to understanding the role of warfare and conflict on the environment in the Mosul region include severe drought and water shortages, including effects of the Turkish GAP water resource development project in the headwaters of the Tigris-Euphrates, as well as Mosul Dam structural problems associated with geologically-unsuitable conditions upon which the dam is constructed. Now, the Islamic State in Iraq and Syria (ISIS) likely captured the Mosul Dam on the day this abstract was submitted. Our Landsat-based monitoring and analysis of the Rebea Project and

  8. 3D real holographic image movies are projected into a volumetric display using dynamic digital micromirror device (DMD) holograms.

    Science.gov (United States)

    Huebschman, Michael L.; Hunt, Jeremy; Garner, Harold R.

    2006-04-01

    The Texas Instruments Digital Micromirror Device (DMD) is being used as the recording medium for display of pre-calculated digital holograms. The high intensity throughput of the reflected laser light from DMD holograms enables volumetric display of projected real images as well as virtual images. A single DMD and single laser projector system has been designed to reconstruct projected images in a 6''x 6''x 4.5'' volumetric display. The volumetric display is composed of twenty-four, 6''-square, PSCT liquid crystal plates which are each cycled on and off to reduce unnecessary scatter in the volume. The DMD is an XGA format array, 1024x768, with 13.6 micron pitch mirrors. This holographic projection system has been used in the assessment of hologram image resolution, maximum image size, optical focusing of the real image, image look-around, and physiological depth cues. Dynamic movement images are projected by transferring the appropriately sequenced holograms to the DMD at movie frame rates.

  9. Mammography with and without radiolucent positioning sheets: Comparison of projected breast area, pain experience, radiation dose and technical image quality

    NARCIS (Netherlands)

    Timmers, Janine; ten Voorde, Marloes; van Engen, Ruben E.; van Landsveld-Verhoeven, Cary; Pijnappel, Ruud; Droogh-de Greve, Kitty; den Heeten, Gerard J.; Broeders, Mireille J. M.

    2015-01-01

    To compare projected breast area, image quality, pain experience and radiation dose between mammography performed with and without radiolucent positioning sheets. 184 women screened in the Dutch breast screening programme (May-June 2012) provided written informed consent to have one additional image

  10. Fundamental remote sensing science research program. Part 1: Status report of the mathematical pattern recognition and image analysis project

    Science.gov (United States)

    Heydorn, R. D.

    1984-01-01

    The Mathematical Pattern Recognition and Image Analysis (MPRIA) Project is concerned with basic research problems related to the study of the Earth from remotely sensed measurement of its surface characteristics. The program goal is to better understand how to analyze the digital image that represents the spatial, spectral, and temporal arrangement of these measurements for purposing of making selected inference about the Earth.

  11. Using the Mars Student Imaging Project to Integrate Science and English into Middle School Classrooms

    Science.gov (United States)

    Lindgren, C. F.; Troy, M. T.; Valderrama, P.

    2005-12-01

    Bringing science to life in a middle school classroom, and getting students excited about writing an English research paper can be a challenge. We met the challenge by using the exploration of Mars with Arizona State University`s (ASU) Mars Student Imaging Project (MSIP). We replaced individuals writing their own research papers with teams writing scientific proposals for use of the 2001 Mars Odyssey Orbiter. The 126 students on our academic team divided themselves into 26 teams. Each team selected a Leader, Archivist, Publicist, and Bibliographer. I was the Principal Investigator for each team. For twelve weeks the teams formally met once a week to discuss their progress and plan strategies for the following week. We created a website to communicate our progress. During the twelve weeks, the major task was to narrow each general topic such as ``Volcanoes on Mars," to a specific topic that could be answered by an 18km by 60km visible light image such as ``Is it Possible to Find the Relative Age of Volcanic Depressions in a Lava Flow Using a Mars Odyssey Image?" In addition to traditional research methods, we also participated in four teleconferences with ASU scientists chaired by Paige Valderrama, Assistant Director of the Mars Education Program. As the project evolved, I guided the teams with content, while the English teacher provided strategies for writing a meaningful persuasive essay, using citations, and recording bibliographical entries. When the proposals were completed, each team created a PowerPoint presentation to introduce their proposal to everyone for peer review. The students were hard, but fair with their evaluations. In several cases, they did not cast one of their three votes for their own! They decided that ten proposals met the criteria established by ASU. Those teams selected one member to use the JMARS software to target locations on Mars. The imagers spent two intensive days learning the software and targeting the surface. When we received

  12. A study to evaluate the reliability of using two-dimensional photographs, three-dimensional images, and stereoscopic projected three-dimensional images for patient assessment

    OpenAIRE

    Zhu, S; Yang, Y; Khambay, B

    2017-01-01

    Clinicians are accustomed to viewing conventional two-dimensional (2D) photographs and assume that viewing three-dimensional (3D) images is similar. Facial images captured in 3D are not viewed in true 3D; this may alter clinical judgement. The aim of this study was to evaluate the reliability of using conventional photographs, 3D images, and stereoscopic projected 3D images to rate the severity of the deformity in pre-surgical class III patients. Forty adult patients were recruited. Eight rat...

  13. Comparison analysis between filtered back projection and algebraic reconstruction technique on microwave imaging

    Science.gov (United States)

    Ramadhan, Rifqi; Prabowo, Rian Gilang; Aprilliyani, Ria; Basari

    2018-02-01

    Victims of acute cancer and tumor are growing each year and cancer becomes one of the causes of human deaths in the world. Cancers or tumor tissue cells are cells that grow abnormally and turn to take over and damage the surrounding tissues. At the beginning, cancers or tumors do not have definite symptoms in its early stages, and can even attack the tissues inside of the body. This phenomena is not identifiable under visual human observation. Therefore, an early detection system which is cheap, quick, simple, and portable is essensially required to anticipate the further development of cancer or tumor. Among all of the modalities, microwave imaging is considered to be a cheaper, simple, and portable system method. There are at least two simple image reconstruction algorithms i.e. Filtered Back Projection (FBP) and Algebraic Reconstruction Technique (ART), which have been adopted in some common modalities. In this paper, both algorithms will be compared by reconstructing the image from an artificial tissue model (i.e. phantom), which has two different dielectric distributions. We addressed two performance comparisons, namely quantitative and qualitative analysis. Qualitative analysis includes the smoothness of the image and also the success in distinguishing dielectric differences by observing the image with human eyesight. In addition, quantitative analysis includes Histogram, Structural Similarity Index (SSIM), Mean Squared Error (MSE), and Peak Signal-to-Noise Ratio (PSNR) calculation were also performed. As a result, quantitative parameters of FBP might show better values than the ART. However, ART is likely more capable to distinguish two different dielectric value than FBP, due to higher contrast in ART and wide distribution grayscale level.

  14. Prevalence of incidental findings on magnetic resonance imaging: Cuban project to map the human brain

    International Nuclear Information System (INIS)

    Hernandez Gonzalez, Gertrudis de los Angeles; Alvarez Sanchez, Marilet; Jordan Gonzalez, Jose

    2010-01-01

    To determine the prevalence of incidental findings in healthy subjects of the Cuban Human Brain Mapping Project sample, it was performed a retrospective descriptive study of the magnetic resonance imaging (MRI) obtained from 394 healthy subjects that make up the sample of the project, between 2006-2007, with an age range of 18 to 68 years (mean 33,12), of which 269 (68,27 %) are male and 125 (31,73 %) are women. It was shown that 40,36 % had one or more anomaly in the magnetic resonance imaging (MRI). In total, the number of incidental findings was 188, 23,6 % of which were brain findings and 24,11 % were non-brain findings, among the latter, were the sinusopathy with 20,81 % and maxillary polyps with 3,30 %. The most prevalent brain findings were: intrasellar arachnoidocele, 11,93 %, followed by the prominence of the pituitary gland, 5,84 %, ventricular asymmetry, 1,77 % and bone defects, 1,02 %. Other brain abnormalities found with very low prevalence had no pathological significance, except for two cases with brain tumor, which were immediately sent to a specialist. Incidental findings in MRI are common in the general population (40,36 %), being the sinusopathy, and intrasellar arachnoidocele the most common findings. Asymptomatic individuals who have any type of structural abnormality provide invaluable information on the prevalence of these abnormalities in a presumably healthy population, which may be used as references for epidemiological studies

  15. Macro optical projection tomography for large scale 3D imaging of plant structures and gene activity.

    Science.gov (United States)

    Lee, Karen J I; Calder, Grant M; Hindle, Christopher R; Newman, Jacob L; Robinson, Simon N; Avondo, Jerome J H Y; Coen, Enrico S

    2017-01-01

    Optical projection tomography (OPT) is a well-established method for visualising gene activity in plants and animals. However, a limitation of conventional OPT is that the specimen upper size limit precludes its application to larger structures. To address this problem we constructed a macro version called Macro OPT (M-OPT). We apply M-OPT to 3D live imaging of gene activity in growing whole plants and to visualise structural morphology in large optically cleared plant and insect specimens up to 60 mm tall and 45 mm deep. We also show how M-OPT can be used to image gene expression domains in 3D within fixed tissue and to visualise gene activity in 3D in clones of growing young whole Arabidopsis plants. A further application of M-OPT is to visualise plant-insect interactions. Thus M-OPT provides an effective 3D imaging platform that allows the study of gene activity, internal plant structures and plant-insect interactions at a macroscopic scale. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  16. An Inter-Projection Interpolation (IPI) Approach with Geometric Model Restriction to Reduce Image Dose in Cone Beam CT (CBCT).

    Science.gov (United States)

    Zhang, Hong; Kong, Fengchong; Ren, Lei; Jin, Jian-Yue

    2014-09-01

    Cone beam computed tomography (CBCT) imaging is a key step in image guided radiation therapy (IGRT) to improve tumor targeting. The quality and imaging dose of CBCT are two important factors. However, X-ray scatter in the large cone beam field usually induces image artifacts and degrades the image quality for CBCT. A synchronized moving grid (SMOG) approach has recently been proposed to resolve this issue and shows great promise. However, the SMOG technique requires two projections in the same gantry angle to obtain full information due to signal blockage by the grid. This study aims to develop an inter-projection interpolation (IPI) method to estimate the blocked image information. This approach will require only one projection in each gantry angle, thus reducing the scan time and patient dose. IPI is also potentially suitable for sparse-view CBCT reconstruction to reduce the imaging dose. To be compared with other state-of-the-art spatial interpolation (called inpainting) methods in terms of signal-to-noise ratio (SNR) on a Catphan and head phantoms, IPI increases SNR from 15.3dB and 12.7dB to 29.0dB and 28.1dB, respectively. The SNR of IPI on sparse-view CBCT reconstruction can achieve from 28dB to 17dB for undersample projection sets with gantry angle interval varying from 1 to 3 degrees for both phantoms.

  17. Femtosecond few- to single-electron point-projection microscopy for nanoscale dynamic imaging

    Science.gov (United States)

    Bainbridge, A. R.; Barlow Myers, C. W.; Bryan, W. A.

    2016-01-01

    Femtosecond electron microscopy produces real-space images of matter in a series of ultrafast snapshots. Pulses of electrons self-disperse under space-charge broadening, so without compression, the ideal operation mode is a single electron per pulse. Here, we demonstrate femtosecond single-electron point projection microscopy (fs-ePPM) in a laser-pump fs-e-probe configuration. The electrons have an energy of only 150 eV and take tens of picoseconds to propagate to the object under study. Nonetheless, we achieve a temporal resolution with a standard deviation of 114 fs (equivalent to a full-width at half-maximum of 269 ± 40 fs) combined with a spatial resolution of 100 nm, applied to a localized region of charge at the apex of a nanoscale metal tip induced by 30 fs 800 nm laser pulses at 50 kHz. These observations demonstrate real-space imaging of reversible processes, such as tracking charge distributions, is feasible whilst maintaining femtosecond resolution. Our findings could find application as a characterization method, which, depending on geometry, could resolve tens of femtoseconds and tens of nanometres. Dynamically imaging electric and magnetic fields and charge distributions on sub-micron length scales opens new avenues of ultrafast dynamics. Furthermore, through the use of active compression, such pulses are an ideal seed for few-femtosecond to attosecond imaging applications which will access sub-optical cycle processes in nanoplasmonics. PMID:27158637

  18. Femtosecond few- to single-electron point-projection microscopy for nanoscale dynamic imaging

    Directory of Open Access Journals (Sweden)

    A. R. Bainbridge

    2016-03-01

    Full Text Available Femtosecond electron microscopy produces real-space images of matter in a series of ultrafast snapshots. Pulses of electrons self-disperse under space-charge broadening, so without compression, the ideal operation mode is a single electron per pulse. Here, we demonstrate femtosecond single-electron point projection microscopy (fs-ePPM in a laser-pump fs-e-probe configuration. The electrons have an energy of only 150 eV and take tens of picoseconds to propagate to the object under study. Nonetheless, we achieve a temporal resolution with a standard deviation of 114 fs (equivalent to a full-width at half-maximum of 269 ± 40 fs combined with a spatial resolution of 100 nm, applied to a localized region of charge at the apex of a nanoscale metal tip induced by 30 fs 800 nm laser pulses at 50 kHz. These observations demonstrate real-space imaging of reversible processes, such as tracking charge distributions, is feasible whilst maintaining femtosecond resolution. Our findings could find application as a characterization method, which, depending on geometry, could resolve tens of femtoseconds and tens of nanometres. Dynamically imaging electric and magnetic fields and charge distributions on sub-micron length scales opens new avenues of ultrafast dynamics. Furthermore, through the use of active compression, such pulses are an ideal seed for few-femtosecond to attosecond imaging applications which will access sub-optical cycle processes in nanoplasmonics.

  19. Usefulness of 3-dimensional stereotactic surface projection FDG PET images for the diagnosis of dementia.

    Science.gov (United States)

    Kim, Jahae; Cho, Sang-Geon; Song, Minchul; Kang, Sae-Ryung; Kwon, Seong Young; Choi, Kang-Ho; Choi, Seong-Min; Kim, Byeong-Chae; Song, Ho-Chun

    2016-12-01

    To compare diagnostic performance and confidence of a standard visual reading and combined 3-dimensional stereotactic surface projection (3D-SSP) results to discriminate between Alzheimer disease (AD)/mild cognitive impairment (MCI), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD).[F]fluorodeoxyglucose (FDG) PET brain images were obtained from 120 patients (64 AD/MCI, 38 DLB, and 18 FTD) who were clinically confirmed over 2 years follow-up. Three nuclear medicine physicians performed the diagnosis and rated diagnostic confidence twice; once by standard visual methods, and once by adding of 3D-SSP. Diagnostic performance and confidence were compared between the 2 methods.3D-SSP showed higher sensitivity, specificity, accuracy, positive, and negative predictive values to discriminate different types of dementia compared with the visual method alone, except for AD/MCI specificity and FTD sensitivity. Correction of misdiagnosis after adding 3D-SSP images was greatest for AD/MCI (56%), followed by DLB (13%) and FTD (11%). Diagnostic confidence also increased in DLB (visual: 3.2; 3D-SSP: 4.1; P visual: 3.1; 3D-SSP: 3.8; P = 0.002) and FTD (visual: 3.5; 3D-SSP: 4.2; P = 0.022). Overall, 154/360 (43%) cases had a corrected misdiagnosis or improved diagnostic confidence for the correct diagnosis.The addition of 3D-SSP images to visual analysis helped to discriminate different types of dementia in FDG PET scans, by correcting misdiagnoses and enhancing diagnostic confidence in the correct diagnosis. Improvement of diagnostic accuracy and confidence by 3D-SSP images might help to determine the cause of dementia and appropriate treatment.

  20. X-ray CT core imaging of Oman Drilling Project on D/V CHIKYU

    Science.gov (United States)

    Michibayashi, K.; Okazaki, K.; Leong, J. A. M.; Kelemen, P. B.; Johnson, K. T. M.; Greenberger, R. N.; Manning, C. E.; Harris, M.; de Obeso, J. C.; Abe, N.; Hatakeyama, K.; Ildefonse, B.; Takazawa, E.; Teagle, D. A. H.; Coggon, J. A.

    2017-12-01

    We obtained X-ray computed tomography (X-ray CT) images for all cores (GT1A, GT2A, GT3A and BT1A) in Oman Drilling Project Phase 1 (OmanDP cores), since X-ray CT scanning is a routine measurement of the IODP measurement plan onboard Chikyu, which enables the non-destructive observation of the internal structure of core samples. X-ray CT images provide information about chemical compositions and densities of the cores and is useful for assessing sample locations and the quality of the whole-round samples. The X-ray CT scanner (Discovery CT 750HD, GE Medical Systems) on Chikyu scans and reconstructs the image of a 1.4 m section in 10 minutes and produces a series of scan images, each 0.625 mm thick. The X-ray tube (as an X-ray source) and the X-ray detector are installed inside of the gantry at an opposing position to each other. The core sample is scanned in the gantry with the scanning rate of 20 mm/sec. The distribution of attenuation values mapped to an individual slice comprises the raw data that are used for subsequent image processing. Successive two-dimensional (2-D) slices of 512 x 512 pixels yield a representation of attenuation values in three-dimensional (3-D) voxels of 512 x 512 by 1600 in length. Data generated for each core consist of core-axis-normal planes (XY planes) of X-ray attenuation values with dimensions of 512 × 512 pixels in 9 cm × 9 cm cross-section, meaning at the dimensions of a core section, the resolution is 0.176 mm/pixel. X-ray intensity varies as a function of X-ray path length and the linear attenuation coefficient (LAC) of the target material is a function of the chemical composition and density of the target material. The basic measure of attenuation, or radiodensity, is the CT number given in Hounsfield units (HU). CT numbers of air and water are -1000 and 0, respectively. Our preliminary results show that CT numbers of OmanDP cores are well correlated to gamma ray attenuation density (GRA density) as a function of chemical

  1. Image and Diagnosis Quality of X-Ray Image Transmission via Cell Phone Camera: A Project Study Evaluating Quality and Reliability

    OpenAIRE

    Goost, Hans; Witten, Johannes; Heck, Andreas; Hadizadeh, Dariusch R.; Weber, Oliver; Gräff, Ingo; Burger, Christof; Montag, Mareen; Koerfer, Felix; Kabir, Koroush

    2012-01-01

    INTRODUCTION: Developments in telemedicine have not produced any relevant benefits for orthopedics and trauma surgery to date. For the present project study, several parameters were examined during assessment of x-ray images, which had been photographed and transmitted via cell phone. MATERIALS AND METHODS: A total of 100 x-ray images of various body regions were photographed with a Nokia cell phone and transmitted via email or MMS. Next, the transmitted photographs were reviewed on a laptop ...

  2. A study to evaluate the reliability of using two-dimensional photographs, three-dimensional images, and stereoscopic projected three-dimensional images for patient assessment.

    Science.gov (United States)

    Zhu, S; Yang, Y; Khambay, B

    2017-03-01

    Clinicians are accustomed to viewing conventional two-dimensional (2D) photographs and assume that viewing three-dimensional (3D) images is similar. Facial images captured in 3D are not viewed in true 3D; this may alter clinical judgement. The aim of this study was to evaluate the reliability of using conventional photographs, 3D images, and stereoscopic projected 3D images to rate the severity of the deformity in pre-surgical class III patients. Forty adult patients were recruited. Eight raters assessed facial height, symmetry, and profile using the three different viewing media and a 100-mm visual analogue scale (VAS), and appraised the most informative viewing medium. Inter-rater consistency was above good for all three media. Intra-rater reliability was not significantly different for rating facial height using 2D (P=0.704), symmetry using 3D (P=0.056), and profile using projected 3D (P=0.749). Using projected 3D for rating profile and symmetry resulted in significantly lower median VAS scores than either 3D or 2D images (all Pprojection was the preferred method for rating. The reliability of assessing specific characteristics was dependent on the viewing medium. Clinicians should be aware that the visual information provided when viewing 3D images is not the same as when viewing 2D photographs, especially for facial depth, and this may change the clinical impression. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  3. Design of the PET-MR system for head imaging of the DREAM Project

    Science.gov (United States)

    González, A. J.; Conde, P.; Hernández, L.; Herrero, V.; Moliner, L.; Monzó, J. M.; Orero, A.; Peiró, A.; Rodríguez-Álvarez, M. J.; Ros, A.; Sánchez, F.; Soriano, A.; Vidal, L. F.; Benlloch, J. M.

    2013-02-01

    In this paper we describe the overall design of a PET-MR system for head imaging within the framework of the DREAM Project as well as the first detector module tests. The PET system design consists of 4 rings of 16 detector modules each and it is expected to be integrated in a head dedicated radio frequency coil of an MR scanner. The PET modules are based on monolithic LYSO crystals coupled by means of optical devices to an array of 256 Silicon Photomultipliers. These types of crystals allow to preserve the scintillation light distribution and, thus, to recover the exact photon impact position with the proper characterization of such a distribution. Every module contains 4 Application Specific Integrated Circuits (ASICs) which return detailed information of several light statistical momenta. The preliminary tests carried out on this design and controlled by means of ASICs have shown promising results towards the suitability of hybrid PET-MR systems.

  4. Short Project-Based Learning with MATLAB Applications to Support the Learning of Video-Image Processing

    Science.gov (United States)

    Gil, Pablo

    2017-10-01

    University courses concerning Computer Vision and Image Processing are generally taught using a traditional methodology that is focused on the teacher rather than on the students. This approach is consequently not effective when teachers seek to attain cognitive objectives involving their students' critical thinking. This manuscript covers the development, implementation and assessment of a short project-based engineering course with MATLAB applications Multimedia Engineering being taken by Bachelor's degree students. The principal goal of all course lectures and hands-on laboratory activities was for the students to not only acquire image-specific technical skills but also a general knowledge of data analysis so as to locate phenomena in pixel regions of images and video frames. This would hopefully enable the students to develop skills regarding the implementation of the filters, operators, methods and techniques used for image processing and computer vision software libraries. Our teaching-learning process thus permits the accomplishment of knowledge assimilation, student motivation and skill development through the use of a continuous evaluation strategy to solve practical and real problems by means of short projects designed using MATLAB applications. Project-based learning is not new. This approach has been used in STEM learning in recent decades. But there are many types of projects. The aim of the current study is to analyse the efficacy of short projects as a learning tool when compared to long projects during which the students work with more independence. This work additionally presents the impact of different types of activities, and not only short projects, on students' overall results in this subject. Moreover, a statistical study has allowed the author to suggest a link between the students' success ratio and the type of content covered and activities completed on the course. The results described in this paper show that those students who took part

  5. Ultrasonic Flaw Detection and Imaging through Reverberant Layers via Subspace Analysis and Projection

    Directory of Open Access Journals (Sweden)

    Ramazan Demirli

    2012-01-01

    Full Text Available Ultrasonic flaw detection and imaging through reverberant layers are challenging problems owing to the layer-induced reverberations and front surface reflections. These undesired signals present a strong clutter and mask the flaw echoes. In this paper, a subspace-based approach is developed for removing, or significantly reducing, the unwanted reverberations, enabling proper flaw detection and imaging. The technique utilizes a set of independent clutter-only reference measurements of the material through the layer. If these measurements are not available, array measurements of the material with flaws are used instead. The clutter, due to its high strength relative to the flaw reflections, forms a subspace spanned by the eigenvectors corresponding to the dominant eigenvalues of the data covariance matrix. The clutter subspace is estimated and removed using orthogonal subspace projection. The clutter usually occupies multidimension subspace that is dependent on the level of coupling, material inhomogeneity, surface roughness, and the sampling rate of the measurements. When the clutter-only reference is not available, information theoretic techniques are used to estimate the dimension of the clutter subspace so that clutter signals are sufficiently suppressed without distorting the flaw signals. The effectiveness of the proposed approach is demonstrated using simulations and real measurement results.

  6. A 3D Kinematic Measurement of Knee Prosthesis Using X-ray Projection Images

    Science.gov (United States)

    Hirokawa, Shunji; Ariyoshi, Shogo; Hossain, Mohammad Abrar

    We have developed a technique for estimating 3D motion of knee prosthesis from its 2D perspective projections. As Fourier descriptors were used for compact representation of library templates and contours extracted from the prosthetic X-ray images, the entire silhouette contour of each prosthetic component was required. This caused such a problem as our algorithm did not function when the silhouettes of tibio and femoral components overlapped with each other. Here we planned a novel method to overcome it; which was processed in two steps. First, the missing part of silhouette contour due to overlap was interpolated using a free-formed curvature such as Bezier. Then the first step position/orientation estimation was performed. In the next step, a clipping window was set in the projective coordinate so as to separate the overlapped silhouette drawn using the first step estimates. After that the localized library whose templates were clipped in shape was prepared and the second step estimation was performed. Computer model simulation demonstrated sufficient accuracies of position/orientation estimation even for overlapped silhouettes; equivalent to those without overlap.

  7. The Salton Seismic Imaging Project: Investigating Earthquake Hazards in the Salton Trough, Southern California

    Science.gov (United States)

    Fuis, G. S.; Goldman, M.; Sickler, R. R.; Catchings, R. D.; Rymer, M. J.; Rose, E. J.; Murphy, J. M.; Butcher, L. A.; Cotton, J. A.; Criley, C. J.; Croker, D. S.; Emmons, I.; Ferguson, A. J.; Gardner, M. A.; Jensen, E. G.; McClearn, R.; Loughran, C. L.; Slayday-Criley, C. J.; Svitek, J. F.; Hole, J. A.; Stock, J. M.; Skinner, S. M.; Driscoll, N. W.; Harding, A. J.; Babcock, J. M.; Kent, G.; Kell, A. M.; Harder, S. H.

    2011-12-01

    The Salton Seismic Imaging Project (SSIP) is a collaborative effort between academia and the U.S. Geological Survey to provide detailed, subsurface 3-D images of the Salton Trough of southern California and northern Mexico. From both active- and passive-source seismic data that were acquired both onshore and offshore (Salton Sea), the resulting images will provide insights into earthquake hazards, rift processes, and rift-transform interaction at the southern end of the San Andreas Fault system. The southernmost San Andreas Fault (SAF) is considered to be at high-risk of producing a large damaging earthquake, yet the structure of this and other regional faults and that of adjacent sedimentary basins is not currently well understood. Seismic data were acquired from 2 to 18 March 2011. One hundred and twenty-six borehole explosions (10-1400 kg yield) were detonated along seven profiles in the Salton Trough region, extending from area of Palm Springs, California, to the southwestern tip of Arizona. Airguns (1500 and 3500 cc) were fired along two profiles in the Salton Sea and at points in a 2-D array in the southern Salton Sea. Approximately 2800 seismometers were deployed at over 4200 locations throughout the Salton Trough region, and 48 ocean-bottom seismometers were deployed at 78 locations beneath the Salton Sea. Many of the onshore explosions were energetic enough to be recorded and located by the Southern California Seismograph Network. The geometry of the SAF has important implications for energy radiation in the next major rupture. Prior potential field, seismicity, and InSAR data indicate that the SAF may dip moderately to the northeast from the Salton Sea to Cajon Pass in the Transverse Ranges. Much of SSIP was designed to test models of this geometry.

  8. Use of the geometric mean of opposing planar projections in pre-reconstruction restoration of SPECT images

    International Nuclear Information System (INIS)

    Boulfelfel, D.; Rangayyan, R.M.; Hahn, L.J.; Kloiber, R.

    1992-01-01

    This paper presents a restoration scheme for single photon emission computed tomography (SPECT) images that performs restoration before reconstruction (pre-reconstruction restoration) from planar (projection) images. In this scheme, the pixel-by-pixel geometric mean of each pair of opposing (conjugate) planar projections is computed prior to the reconstruction process. The averaging process is shown to help in making the degradation phenomenon less dependent on the distance of each point of the object from the camera. The restoration filters investigated are the Wiener and power spectrum equalization filters. (author)

  9. Reconstruction of computed tomographic image from a few x-ray projections by means of accelerative gradient method

    International Nuclear Information System (INIS)

    Kobayashi, Fujio; Yamaguchi, Shoichiro

    1982-01-01

    A method of the reconstruction of computed tomographic images was proposed to reduce the exposure dose to X-ray. The method is the small number of X-ray projection method by accelerative gradient method. The procedures of computation are described. The algorithm of these procedures is simple, the convergence of the computation is fast, and the required memory capacity is small. Numerical simulation was carried out to conform the validity of this method. A sample of simple shape was considered, projection data were given, and the images were reconstructed from 6 views. Good results were obtained, and the method is considered to be useful. (Kato, T.)

  10. Exact fan-beam image reconstruction algorithm for truncated projection data acquired from an asymmetric half-size detector

    International Nuclear Information System (INIS)

    Leng Shuai; Zhuang Tingliang; Nett, Brian E; Chen Guanghong

    2005-01-01

    In this paper, we present a new algorithm designed for a specific data truncation problem in fan-beam CT. We consider a scanning configuration in which the fan-beam projection data are acquired from an asymmetrically positioned half-sized detector. Namely, the asymmetric detector only covers one half of the scanning field of view. Thus, the acquired fan-beam projection data are truncated at every view angle. If an explicit data rebinning process is not invoked, this data acquisition configuration will reek havoc on many known fan-beam image reconstruction schemes including the standard filtered backprojection (FBP) algorithm and the super-short-scan FBP reconstruction algorithms. However, we demonstrate that a recently developed fan-beam image reconstruction algorithm which reconstructs an image via filtering a backprojection image of differentiated projection data (FBPD) survives the above fan-beam data truncation problem. Namely, we may exactly reconstruct the whole image object using the truncated data acquired in a full scan mode (2π angular range). We may also exactly reconstruct a small region of interest (ROI) using the truncated projection data acquired in a short-scan mode (less than 2π angular range). The most important characteristic of the proposed reconstruction scheme is that an explicit data rebinning process is not introduced. Numerical simulations were conducted to validate the new reconstruction algorithm

  11. Super Resolution Image Enhancement for a Flash Lidar: Back Projection Method

    Science.gov (United States)

    Bulyshev, Alexander; Hines, Glenn; Vanek, Michael; Amzajerdian, Farzin; Reisse, Robert; Pierrottet, Diego

    2010-01-01

    In this paper a new image processing technique for flash LIDAR data is presented as a potential tool to enable safe and precise spacecraft landings in future robotic or crewed lunar and planetary missions. Flash LIDARs can generate, in real-time, range data that can be interpreted as a 3-dimensional (3-D) image and transformed into a corresponding digital elevation map (DEM). The NASA Autonomous Landing and Hazard Avoidance (ALHAT) project is capitalizing on this new technology by developing, testing and analyzing flash LIDARs to detect hazardous terrain features such as craters, rocks, and slopes during the descent phase of spacecraft landings. Using a flash LIDAR for this application looks very promising, however through theoretical and simulation analysis the ALHAT team has determined that a single frame, or mosaic, of flash LIDAR data may not be sufficient to build a landing site DEM with acceptable spatial resolution, precision, size, or for a mosaic, in time, to meet current system requirements. One way to overcome this potential limitation is by enhancing the flash LIDAR output images. We propose a new super-resolution algorithm applicable to flash LIDAR range data that will create a DEM with sufficient accuracy, precision and size to meet current ALHAT requirements. The performance of our super-resolution algorithm is analyzed by processing data generated during a series of simulation runs by a high fidelity model of a flash LIDAR imaging a high resolution synthetic lunar elevation map. The flash LIDAR model is attached to a simulated spacecraft by a gimbal that points the LIDAR to a target landing site. For each simulation run, a sequence of flash LIDAR frames is recorded and processed as the spacecraft descends toward the landing site. Each run has a different trajectory profile with varying LIDAR look angles of the terrain. We process the output LIDAR frames using our SR algorithm and the results show that the achieved level of accuracy and precision of

  12. Multidetector CT evaluation of central airways stenoses: Comparison of virtual bronchoscopy, minimal-intensity projection, and multiplanar reformatted images

    Directory of Open Access Journals (Sweden)

    Dinesh K Sundarakumar

    2011-01-01

    Full Text Available Aims: To evaluate the diagnostic utility of virtual bronchoscopy, multiplanar reformatted images, and minimal-intensity projection in assessing airway stenoses. Settings and Design: It was a prospective study involving 150 patients with symptoms of major airway disease. Materials and Methods: Fifty-six patients were selected for analysis based on the detection of major airway lesions on fiber-optic bronchoscopy (FB or routine axial images. Comparisons were made between axial images, virtual bronchoscopy (VB, minimal-intensity projection (minIP, and multiplanar reformatted (MPR images using FB as the gold standard. Lesions were evaluated in terms of degree of airway narrowing, distance from carina, length of the narrowed segment and visualization of airway distal to the lesion. Results: MPR images had the highest degree of agreement with FB (Κ = 0.76 in the depiction of degree of narrowing. minIP had the least degree of agreement with FB (Κ = 0.51 in this regard. The distal visualization was best on MPR images (84.2%, followed by axial images (80.7%, whereas FB could visualize the lesions only in 45.4% of the cases. VB had the best agreement with FB in assessing the segment length (Κ = 0.62. Overall there were no statistically significant differences in the measurement of the distance from the carina in the axial, minIP, and MPR images. MPR images had the highest overall degree of confidence, namely, 70.17% (n = 40. Conclusion: Three-dimensional reconstruction techniques were found to improve lesion evaluation compared with axial images alone. The technique of MPR images was the most useful for lesion evaluation and provided additional information useful for surgical and airway interventions in tracheobronchial stenosis. minIP was useful in the overall depiction of airway anatomy.

  13. Fast polyenergetic forward projection for image formation using OpenCL on a heterogeneous parallel computing platform.

    Science.gov (United States)

    Zhou, Lili; Clifford Chao, K S; Chang, Jenghwa

    2012-11-01

    Simulated projection images of digital phantoms constructed from CT scans have been widely used for clinical and research applications but their quality and computation speed are not optimal for real-time comparison with the radiography acquired with an x-ray source of different energies. In this paper, the authors performed polyenergetic forward projections using open computing language (OpenCL) in a parallel computing ecosystem consisting of CPU and general purpose graphics processing unit (GPGPU) for fast and realistic image formation. The proposed polyenergetic forward projection uses a lookup table containing the NIST published mass attenuation coefficients (μ∕ρ) for different tissue types and photon energies ranging from 1 keV to 20 MeV. The CT images of interested sites are first segmented into different tissue types based on the CT numbers and converted to a three-dimensional attenuation phantom by linking each voxel to the corresponding tissue type in the lookup table. The x-ray source can be a radioisotope or an x-ray generator with a known spectrum described as weight w(n) for energy bin E(n). The Siddon method is used to compute the x-ray transmission line integral for E(n) and the x-ray fluence is the weighted sum of the exponential of line integral for all energy bins with added Poisson noise. To validate this method, a digital head and neck phantom constructed from the CT scan of a Rando head phantom was segmented into three (air, gray∕white matter, and bone) regions for calculating the polyenergetic projection images for the Mohan 4 MV energy spectrum. To accelerate the calculation, the authors partitioned the workloads using the task parallelism and data parallelism and scheduled them in a parallel computing ecosystem consisting of CPU and GPGPU (NVIDIA Tesla C2050) using OpenCL only. The authors explored the task overlapping strategy and the sequential method for generating the first and subsequent DRRs. A dispatcher was designed to drive

  14. Conditions and mechanism for the appearance of interlobar fissures as 5-line signs in axial maximum intensity projection images.

    Science.gov (United States)

    Yu, Anle; Li, Qun; He, Jinlong; Zhan, Yuefu

    2014-01-01

    To assess the conditions and mechanism for the 5-line sign of normal interlobar fissures revealed on axial maximum intensity projection (MIP). Fifty subjects (32 males and 18 females aged 16 to 76 years) whose conditions were diagnosed as normal on computed tomography (CT) of the chest were presented. Images for the fissures with a slice thickness of 1.25 mm, a space thickness of 1.25 mm, and an MIP slab thickness of 6.25 mm were reconstructed. A 5-line shadow of normal interlobar fissures was shown on axial MIP imaging using a slab thickness of 6.25 mm. On axial MIP imaging, 93% of interlobar fissure parts were manifested as clear or barely clear. On axial MIP imaging using a slab thickness of 6.25 mm, normal interlobar fissures were displayed as 5-line signs, which, similar to the beaded small lung vessels shown on MIP imaging, might be a partial volume-averaging phenomenon.

  15. Physics meets fine arts: a project-based learning path on infrared imaging

    Science.gov (United States)

    Bonanno, A.; Bozzo, G.; Sapia, P.

    2018-03-01

    Infrared imaging represents a noninvasive tool for cultural heritage diagnostics, based on the capability of IR radiation to penetrate the most external layers of different objects (as for example paintings), revealing hidden features of artworks. From an educational viewpoint, this diagnostic technique offers teachers the opportunity to address manifold topics pertaining to the physics and technology of electromagnetic radiation, with particular emphasis on the nature of color and its physical correlates. Moreover, the topic provides interesting interdisciplinary bridges towards the human sciences. In this framework, we present a hands-on learning sequence, suitable for both high school students and university freshmen, inspired by the project-based learning (PBL) paradigm, designed and implemented in the context of an Italian national project aimed at offering students the opportunity to participate in educational activities within a real working context. In a preliminary test we involved a group of 23 high school students while they were working as apprentices in the Laboratory of Applied Physics for Cultural Heritage (ArcheoLab) at the University of Calabria. Consistently with the PBL paradigm, students were given well-defined practical goals to be achieved. As final goals they were asked (i) to construct and to test a low cost device (based on a disused commercial camera) appropriate for performing educational-grade IR investigations on paintings, and (ii) to prepare a device working as a simple spectrometer (recycling the optical components of a disused video projector), suitable for characterizing various light sources in order to identify the most appropriate for infrared imaging. The proposed learning path has shown (in the preliminary test) to be effective in fostering students’ interest towards physics and its technological applications, especially because pupils perceived the context (i.e. physics applied to the protection and restoration of cultural

  16. High Resolution Mineral Mapping of the Oman Drilling Project Cores with Imaging Spectroscopy: Preliminary Results

    Science.gov (United States)

    Greenberger, R. N.; Ehlmann, B. L.; Kelemen, P. B.; Manning, C. E.; Teagle, D. A. H.; Harris, M.; Michibayashi, K.; Takazawa, E.

    2017-12-01

    The Oman Drilling Project provides an unprecedented opportunity to study the formation and alteration of oceanic crust and peridotite. Key to answering the main questions of the project are a characterization of the primary and secondary minerals present within the drill core and their spatial relationships. To that end, we used the Caltech imaging spectrometer system to scan the entire 1.5-km archive half of the core from all four gabbro and listvenite boreholes (GT1A, GT2A, GT3A, and BT1B) at 250 µm/pixel aboard the JAMSTEC Drilling Vessel Chikyu during the ChikyuOman core description campaign. The instrument measures the visible and shortwave infrared reflectance spectra of the rocks as a function of wavelength from 0.4 to 2.6 µm. This wavelength range is sensitive to many mineral groups, including hydrated minerals (phyllosilicates, zeolites, amorphous silica polytypes), carbonates, sulfates, and transition metals, most commonly iron-bearing mineralogies. To complete the measurements, the core was illuminated with a halogen light source and moved below the spectrometer at 1 cm/s by the Chikyu's Geotek track. Data are corrected and processed to reflectance using measurements of dark current and a spectralon calibration panel. The data provide a unique view of the mineralogy at high spatial resolution. Analysis of the images for complete downhole trends is ongoing. Thus far, a variety of minerals have been identified within their petrologic contexts, including but not limited to magnesite, dolomite, calcite, quartz (through an Si-OH absorption due to minor H2O), serpentine, chlorite, epidote, zeolites, mica (fuchsite), kaolinite, prehnite, gypsum, amphibole, and iron oxides. Further analysis will likely identify more minerals. Results include rapidly distinguishing the cations present within carbonate minerals and identifying minerals of volumetrically-low abundance within the matrix and veins of core samples. This technique, for example, accurately identifies

  17. Mammography with and without radiolucent positioning sheets : Comparison of projected breast area, pain experience, radiation dose and technical image quality

    NARCIS (Netherlands)

    Timmers, Janine; ten Voorde, Marloes; van Engen, Ruben E.; van Landsveld-Verhoeven, Cary; Pijnappel, Ruud; Droogh-de Greve, Kitty; den Heeten, Gerard J.; Broeders, Mireille J. M.

    2015-01-01

    Purpose: To compare projected breast area, image quality, pain experience and radiation dose between mammography performed with and without radiolucent positioning sheets. Methods: 184 women screened in the Dutch breast screening programme (May-June 2012) provided written informed consent to have

  18. False-color images from observations by the Supernova Cosmology Project of one of the two most dista

    Science.gov (United States)

    2002-01-01

    TFalse-color images from observations by the Supernova Cosmology Project of one of the two most distant spectroscopically confirmed supernova. From the left: the first two images, from the Cerro Tololo Interamerican Observatory 4-meter telescope, show a small region of sky just before and just after the the appearance of a type-Ia supernova that exploded when the universe was about half its present age. The third image shows the same supernova as observed with the Hubble Space Telescope. This much sharper picture allows a much better measurement of the apparent brightness and hence the distance of this supernova. Because their intrinsic brightness is predictable, such supernovae help to determine the deceleration, and so the eventual fate, of the universe. Credit: Perlmutter et al., The Supernova Cosmology Project

  19. Primary care provider and imaging technician satisfaction with a teledermatology project in rural Veterans Health Administration clinics.

    Science.gov (United States)

    McFarland, Lynne V; Raugi, Gregory J; Reiber, Gayle E

    2013-11-01

    Assessment of a multisite rural teledermatology project between 2009 and 2012 in four Pacific Northwest states that trained primary care providers and imaging technicians in state-of-the-art techniques of telemedicine. In 2012, we assessed provider and imaging technician acceptability and satisfaction with a 32-item survey instrument based on the Patient Satisfaction Questionnaire developed by Ware et al. (Eval Program Plann 1983;6:247-63) and modified for telemedicine by Kraai et al. (J Card Fail 2011;17:684-690). Survey questions covered eight satisfaction domains: interpersonal manner, technical quality, accessibility, finances, efficacy, continuity, physical environment, and availability. Overall, 71% of the primary care providers and 94% of the imaging technicians reported being satisfied or extremely satisfied with the teledermatology project. Most (95%) providers found the continuing education classes on dermatology diagnosis and treatment topics useful, and 86% reported teledermatology was a good addition to regular patient services. Most (97%) of the imaging technicians were satisfied with the ability of teledermatology to improve the description of dermatology conditions using images of the lesions or rashes, and 91% were satisfied with the convenience of teledermatology. Challenges reported by both providers and imaging technicians include an increase in workload due to more patient visits related to dermatology care and limited information technology support. Given the Veterans Health Administration's initiatives to promote accessible health care to underserved Veterans using telehealth, these findings can inform future program designs for teledermatology.

  20. The Yosemite Extreme Panoramic Imaging Project: Monitoring Rockfall in Yosemite Valley with High-Resolution, Three-Dimensional Imagery

    Science.gov (United States)

    Stock, G. M.; Hansen, E.; Downing, G.

    2008-12-01

    Yosemite Valley experiences numerous rockfalls each year, with over 600 rockfall events documented since 1850. However, monitoring rockfall activity has proved challenging without high-resolution "basemap" imagery of the Valley walls. The Yosemite Extreme Panoramic Imaging Project, a partnership between the National Park Service and xRez Studio, has created an unprecedented image of Yosemite Valley's walls by utilizing gigapixel panoramic photography, LiDAR-based digital terrain modeling, and three-dimensional computer rendering. Photographic capture was accomplished by 20 separate teams shooting from key overlapping locations throughout Yosemite Valley. The shots were taken simultaneously in order to ensure uniform lighting, with each team taking over 500 overlapping shots from each vantage point. Each team's shots were then assembled into 20 gigapixel panoramas. In addition, all 20 gigapixel panoramas were projected onto a 1 meter resolution digital terrain model in three-dimensional rendering software, unifying Yosemite Valley's walls into a vertical orthographic view. The resulting image reveals the geologic complexity of Yosemite Valley in high resolution and represents one of the world's largest photographic captures of a single area. Several rockfalls have already occurred since image capture, and repeat photography of these areas clearly delineates rockfall source areas and failure dynamics. Thus, the imagery has already proven to be a valuable tool for monitoring and understanding rockfall in Yosemite Valley. It also sets a new benchmark for the quality of information a photographic image, enabled with powerful new imaging technology, can provide for the earth sciences.

  1. Image quality and dose in mammography in 17 countries in Africa, Asia and Eastern Europe: Results from IAEA projects

    International Nuclear Information System (INIS)

    Ciraj-Bjelac, Olivera; Avramova-Cholakova, Simona; Beganovic, Adnan; Economides, Sotirios; Faj, Dario; Gershan, Vesna; Grupetta, Edward; Kharita, M.H.; Milakovic, Milomir; Milu, Constantin; Muhogora, Wilbroad E.; Muthuvelu, Pirunthavany; Oola, Samuel; Setayeshi, Saeid

    2012-01-01

    Purpose: The objective is to study mammography practice from an optimisation point of view by assessing the impact of simple and immediately implementable corrective actions on image quality. Materials and methods: This prospective multinational study included 54 mammography units in 17 countries. More than 21,000 mammography images were evaluated using a three-level image quality scoring system. Following initial assessment, appropriate corrective actions were implemented and image quality was re-assessed in 24 units. Results: The fraction of images that were considered acceptable without any remark in the first phase (before the implementation of corrective actions) was 70% and 75% for cranio-caudal and medio-lateral oblique projections, respectively. The main causes for poor image quality before corrective actions were related to film processing, damaged or scratched image receptors, or film-screen combinations that are not spectrally matched, inappropriate radiographic techniques and lack of training. Average glandular dose to a standard breast was 1.5 mGy (mean and range 0.59–3.2 mGy). After optimisation the frequency of poor quality images decreased, but the relative contributions of the various causes remained similar. Image quality improvements following appropriate corrective actions were up to 50 percentage points in some facilities. Conclusions: Poor image quality is a major source of unnecessary radiation dose to the breast. An increased awareness of good quality mammograms is of particular importance for countries that are moving towards introduction of population-based screening programmes. The study demonstrated how simple and low-cost measures can be a valuable tool in improving of image quality in mammography

  2. SU-C-209-05: Monte Carlo Model of a Prototype Backscatter X-Ray (BSX) Imager for Projective and Selective Object-Plane Imaging

    International Nuclear Information System (INIS)

    Rolison, L; Samant, S; Baciak, J; Jordan, K

    2016-01-01

    Purpose: To develop a Monte Carlo N-Particle (MCNP) model for the validation of a prototype backscatter x-ray (BSX) imager, and optimization of BSX technology for medical applications, including selective object-plane imaging. Methods: BSX is an emerging technology that represents an alternative to conventional computed tomography (CT) and projective digital radiography (DR). It employs detectors located on the same side as the incident x-ray source, making use of backscatter and avoiding ring geometry to enclose the imaging object. Current BSX imagers suffer from low spatial resolution. A MCNP model was designed to replicate a BSX prototype used for flaw detection in industrial materials. This prototype consisted of a 1.5mm diameter 60kVp pencil beam surrounded by a ring of four 5.0cm diameter NaI scintillation detectors. The imaging phantom consisted of a 2.9cm thick aluminum plate with five 0.6cm diameter holes drilled halfway. The experimental image was created using a raster scanning motion (in 1.5mm increments). Results: A qualitative comparison between the physical and simulated images showed very good agreement with 1.5mm spatial resolution in plane perpendicular to incident x-ray beam. The MCNP model developed the concept of radiography by selective plane detection (RSPD) for BSX, whereby specific object planes can be imaged by varying kVp. 10keV increments in mean x-ray energy yielded 4mm thick slice resolution in the phantom. Image resolution in the MCNP model can be further increased by increasing the number of detectors, and decreasing raster step size. Conclusion: MCNP modelling was used to validate a prototype BSX imager and introduce the RSPD concept, allowing for selective object-plane imaging. There was very good visual agreement between the experimental and MCNP imaging. Beyond optimizing system parameters for the existing prototype, new geometries can be investigated for volumetric image acquisition in medical applications. This material is

  3. PLÉIADES PROJECT: ASSESSMENT OF GEOREFERENCING ACCURACY, IMAGE QUALITY, PANSHARPENING PERFORMENCE AND DSM/DTM QUALITY

    Directory of Open Access Journals (Sweden)

    H. Topan

    2016-06-01

    Full Text Available Pléiades 1A and 1B are twin optical satellites of Optical and Radar Federated Earth Observation (ORFEO program jointly running by France and Italy. They are the first satellites of Europe with sub-meter resolution. Airbus DS (formerly Astrium Geo runs a MyGIC (formerly Pléiades Users Group program to validate Pléiades images worldwide for various application purposes. The authors conduct three projects, one is within this program, the second is supported by BEU Scientific Research Project Program, and the third is supported by TÜBİTAK. Assessment of georeferencing accuracy, image quality, pansharpening performance and Digital Surface Model/Digital Terrain Model (DSM/DTM quality subjects are investigated in these projects. For these purposes, triplet panchromatic (50 cm Ground Sampling Distance (GSD and VNIR (2 m GSD Pléiades 1A images were investigated over Zonguldak test site (Turkey which is urbanised, mountainous and covered by dense forest. The georeferencing accuracy was estimated with a standard deviation in X and Y (SX, SY in the range of 0.45m by bias corrected Rational Polynomial Coefficient (RPC orientation, using ~170 Ground Control Points (GCPs. 3D standard deviation of ±0.44m in X, ±0.51m in Y, and ±1.82m in Z directions have been reached in spite of the very narrow angle of convergence by bias corrected RPC orientation. The image quality was also investigated with respect to effective resolution, Signal to Noise Ratio (SNR and blur coefficient. The effective resolution was estimated with factor slightly below 1.0, meaning that the image quality corresponds to the nominal resolution of 50cm. The blur coefficients were achieved between 0.39-0.46 for triplet panchromatic images, indicating a satisfying image quality. SNR is in the range of other comparable space borne images which may be caused by de-noising of Pléiades images. The pansharpened images were generated by various methods, and are validated by most common

  4. Lossless and lossy compression of images from the OMC experiment of integral project

    Czech Academy of Sciences Publication Activity Database

    Bernas, M.; Páta, P.; Hudec, René

    1999-01-01

    Roč. 39, - (1999), s. 429-432 ISSN 0888-6512 Institutional research plan: CEZ:AV0Z1003909 Keywords : image processing * image compression * astronomical images Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 1.392, year: 1998

  5. Fundamental remote science research program. Part 2: Status report of the mathematical pattern recognition and image analysis project

    Science.gov (United States)

    Heydorn, R. P.

    1984-01-01

    The Mathematical Pattern Recognition and Image Analysis (MPRIA) Project is concerned with basic research problems related to the study of he Earth from remotely sensed measurements of its surface characteristics. The program goal is to better understand how to analyze the digital image that represents the spatial, spectral, and temporal arrangement of these measurements for purposing of making selected inferences about the Earth. This report summarizes the progress that has been made toward this program goal by each of the principal investigators in the MPRIA Program.

  6. Image and diagnosis quality of X-ray image transmission via cell phone camera: a project study evaluating quality and reliability.

    Directory of Open Access Journals (Sweden)

    Hans Goost

    Full Text Available INTRODUCTION: Developments in telemedicine have not produced any relevant benefits for orthopedics and trauma surgery to date. For the present project study, several parameters were examined during assessment of x-ray images, which had been photographed and transmitted via cell phone. MATERIALS AND METHODS: A total of 100 x-ray images of various body regions were photographed with a Nokia cell phone and transmitted via email or MMS. Next, the transmitted photographs were reviewed on a laptop computer by five medical specialists and assessed regarding quality and diagnosis. RESULTS: Due to their poor quality, the transmitted MMS images could not be evaluated and this path of transmission was therefore excluded. Mean size of transmitted x-ray email images was 394 kB (range: 265-590 kB, SD ± 59, average transmission time was 3.29 min ± 8 (CI 95%: 1.7-4.9. Applying a score from 1-10 (very poor - excellent, mean image quality was 5.8. In 83.2 ± 4% (mean value ± SD of cases (median 82; 80-89%, there was agreement between final diagnosis and assessment by the five medical experts who had received the images. However, there was a markedly low concurrence ratio in the thoracic area and in pediatric injuries. DISCUSSION: While the rate of accurate diagnosis and indication for surgery was high with a concurrence ratio of 83%, considerable differences existed between the assessed regions, with lowest values for thoracic images. Teleradiology is a cost-effective, rapid method which can be applied wherever wireless cell phone reception is available. In our opinion, this method is in principle suitable for clinical use, enabling the physician on duty to agree on appropriate measures with colleagues located elsewhere via x-ray image transmission on a cell phone.

  7. Image and diagnosis quality of X-ray image transmission via cell phone camera: a project study evaluating quality and reliability.

    Science.gov (United States)

    Goost, Hans; Witten, Johannes; Heck, Andreas; Hadizadeh, Dariusch R; Weber, Oliver; Gräff, Ingo; Burger, Christof; Montag, Mareen; Koerfer, Felix; Kabir, Koroush

    2012-01-01

    Developments in telemedicine have not produced any relevant benefits for orthopedics and trauma surgery to date. For the present project study, several parameters were examined during assessment of x-ray images, which had been photographed and transmitted via cell phone. A total of 100 x-ray images of various body regions were photographed with a Nokia cell phone and transmitted via email or MMS. Next, the transmitted photographs were reviewed on a laptop computer by five medical specialists and assessed regarding quality and diagnosis. Due to their poor quality, the transmitted MMS images could not be evaluated and this path of transmission was therefore excluded. Mean size of transmitted x-ray email images was 394 kB (range: 265-590 kB, SD ± 59), average transmission time was 3.29 min ± 8 (CI 95%: 1.7-4.9). Applying a score from 1-10 (very poor - excellent), mean image quality was 5.8. In 83.2 ± 4% (mean value ± SD) of cases (median 82; 80-89%), there was agreement between final diagnosis and assessment by the five medical experts who had received the images. However, there was a markedly low concurrence ratio in the thoracic area and in pediatric injuries. While the rate of accurate diagnosis and indication for surgery was high with a concurrence ratio of 83%, considerable differences existed between the assessed regions, with lowest values for thoracic images. Teleradiology is a cost-effective, rapid method which can be applied wherever wireless cell phone reception is available. In our opinion, this method is in principle suitable for clinical use, enabling the physician on duty to agree on appropriate measures with colleagues located elsewhere via x-ray image transmission on a cell phone.

  8. Teaching strategies for using projected images to develop conceptual understanding: Exploring discussion practices in computer simulation and static image-based lessons

    Science.gov (United States)

    Price, Norman T.

    The availability and sophistication of visual display images, such as simulations, for use in science classrooms has increased exponentially however, it can be difficult for teachers to use these images to encourage and engage active student thinking. There is a need to describe flexible discussion strategies that use visual media to engage active thinking. This mixed methods study analyzes teacher behavior in lessons using visual media about the particulate model of matter that were taught by three experienced middle school teachers. Each teacher taught one half of their students with lessons using static overheads and taught the other half with lessons using a projected dynamic simulation. The quantitative analysis of pre-post data found significant gain differences between the two image mode conditions, suggesting that the students who were assigned to the simulation condition learned more than students who were assigned to the overhead condition. Open coding was used to identify a set of eight image-based teaching strategies that teachers were using with visual displays. Fixed codes for this set of image-based discussion strategies were then developed and used to analyze video and transcripts of whole class discussions from 12 lessons. The image-based discussion strategies were refined over time in a set of three in-depth 2x2 comparative case studies of two teachers teaching one lesson topic with two image display modes. The comparative case study data suggest that the simulation mode may have offered greater affordances than the overhead mode for planning and enacting discussions. The 12 discussions were also coded for overall teacher student interaction patterns, such as presentation, IRE, and IRF. When teachers moved during a lesson from using no image to using either image mode, some teachers were observed asking more questions when the image was displayed while others asked many fewer questions. The changes in teacher student interaction patterns suggest

  9. Digital tomosynthesis parallel imaging computational analysis with shift and add and back projection reconstruction algorithms.

    Science.gov (United States)

    Chen, Ying; Balla, Apuroop; Rayford II, Cleveland E; Zhou, Weihua; Fang, Jian; Cong, Linlin

    2010-01-01

    Digital tomosynthesis is a novel technology that has been developed for various clinical applications. Parallel imaging configuration is utilised in a few tomosynthesis imaging areas such as digital chest tomosynthesis. Recently, parallel imaging configuration for breast tomosynthesis began to appear too. In this paper, we present the investigation on computational analysis of impulse response characterisation as the start point of our important research efforts to optimise the parallel imaging configurations. Results suggest that impulse response computational analysis is an effective method to compare and optimise imaging configurations.

  10. Fast, accurate, and robust automatic marker detection for motion correction based on oblique kV or MV projection image pairs

    International Nuclear Information System (INIS)

    Slagmolen, Pieter; Hermans, Jeroen; Maes, Frederik; Budiharto, Tom; Haustermans, Karin; Heuvel, Frank van den

    2010-01-01

    Purpose: A robust and accurate method that allows the automatic detection of fiducial markers in MV and kV projection image pairs is proposed. The method allows to automatically correct for inter or intrafraction motion. Methods: Intratreatment MV projection images are acquired during each of five treatment beams of prostate cancer patients with four implanted fiducial markers. The projection images are first preprocessed using a series of marker enhancing filters. 2D candidate marker locations are generated for each of the filtered projection images and 3D candidate marker locations are reconstructed by pairing candidates in subsequent projection images. The correct marker positions are retrieved in 3D by the minimization of a cost function that combines 2D image intensity and 3D geometric or shape information for the entire marker configuration simultaneously. This optimization problem is solved using dynamic programming such that the globally optimal configuration for all markers is always found. Translational interfraction and intrafraction prostate motion and the required patient repositioning is assessed from the position of the centroid of the detected markers in different MV image pairs. The method was validated on a phantom using CT as ground-truth and on clinical data sets of 16 patients using manual marker annotations as ground-truth. Results: The entire setup was confirmed to be accurate to around 1 mm by the phantom measurements. The reproducibility of the manual marker selection was less than 3.5 pixels in the MV images. In patient images, markers were correctly identified in at least 99% of the cases for anterior projection images and 96% of the cases for oblique projection images. The average marker detection accuracy was 1.4±1.8 pixels in the projection images. The centroid of all four reconstructed marker positions in 3D was positioned within 2 mm of the ground-truth position in 99.73% of all cases. Detecting four markers in a pair of MV images

  11. A Visual Database System for Image Analysis on Parallel Computers and its Application to the EOS Amazon Project

    Science.gov (United States)

    Shapiro, Linda G.; Tanimoto, Steven L.; Ahrens, James P.

    1996-01-01

    The goal of this task was to create a design and prototype implementation of a database environment that is particular suited for handling the image, vision and scientific data associated with the NASA's EOC Amazon project. The focus was on a data model and query facilities that are designed to execute efficiently on parallel computers. A key feature of the environment is an interface which allows a scientist to specify high-level directives about how query execution should occur.

  12. The myImageAnalysis Project: A Web-Based Application for High-Content Screening

    OpenAIRE

    Szafran, Adam T.; Mancini, Michael A.

    2014-01-01

    A major challenge faced by screening centers developing image-based assays is the wide range of assays needed compared to the limited resources that are available to effectively analyze and manage them. To overcome this limitation, we have developed the web-based myImageAnalysis (mIA) application, integrated with an open database connectivity compliant database and powered by Pipeline Pilot (PLP) that incorporates dataset tracking, scheduling and archiving, image analysis, and data reporting....

  13. Imaging Seafloor Massive Sulphides at the TAG hydrothermal fields, from the Blue Mining seismic project

    Science.gov (United States)

    Gil de la Iglesia, Alba; Vardy, Mark; Bialas, Jörg; Dannowski, Anke; Schröder, Henning; Minshull, Tim; Chidlow, Kasia; Murton, Bramly

    2017-04-01

    The Trans-Atlantic Geotraverse (TAG) hydrothermal field, located at the Mid-Atlantic Ridge (26°N), is known for the existence of Seafloor Massive Sulphides (SMS) discovered by the Trans-Atlantic Geotraverse cruise (Rona et al., 1986). The TAG comprises a low-temperature alteration zone, five inactive, high-temperature hydrothermal deposits, and the hydrothermal active TAG mound. TAG is also known for being one of the eight known SMS with a size larger than 2M tones (Hannington et al., 2011). The known SMS deposits do not have the same dimensions as the Massive Sulphides (MS) found on land, covering areas from 10s-100s m2 and their accessibility is more complicated, being located at 800-6000 m water depth. Although they do not seem to be economically exploitable at present, those deep-sea mineral resources could be important targets in the near future. One of the aims of the European-funded Blue Mining project is to identify the SMS deposit dimensions for the future environmentally sustainable and clean deep-sea mining. The Blue Mining project is focused on the extinct Seafloor Massive Sulphides (eSMS) in the TAG hydrothermal field, in particular Shinkai, Southern and Shimmering mounds. In May/June 2016 the German RV METEOR carried out a seismic refraction/reflection wide-angle (WA) experiment acquiring thirty multichannel seismic (MCS) profiles crossing the TAG hydrothermal field. GEOMAR's 2-unit air-gun array with a total volume of 760 cubic-inches was used, triggering seismic pulses every 12 s along the MCS profiles. Reflected and refracted events from the shallow-towed sources were recorded by 20 Ocean Bottom Seismometers (OBS) and 5 Ocean Bottom Hydrophones (OBH). To obtain the internal velocities and gross geometries of these deposits, 10 of 20 OBS were located on top of the eSMS, Shinaki and Southern mounds, while the other 10 instruments were located in extension of the profiles, covering Shimmering mounds and regional targets. In this presentation, we

  14. Final report on LDRD project : single-photon-sensitive imaging detector arrays at 1600 nm.

    Energy Technology Data Exchange (ETDEWEB)

    Childs, Kenton David; Serkland, Darwin Keith; Geib, Kent Martin; Hawkins, Samuel D.; Carroll, Malcolm S.; Klem, John Frederick; Sheng, Josephine Juin-Jye; Patel, Rupal K.; Bolles, Desta; Bauer, Tom M.; Koudelka, Robert

    2006-11-01

    The key need that this project has addressed is a short-wave infrared light detector for ranging (LIDAR) imaging at temperatures greater than 100K, as desired by nonproliferation and work for other customers. Several novel device structures to improve avalanche photodiodes (APDs) were fabricated to achieve the desired APD performance. A primary challenge to achieving high sensitivity APDs at 1550 nm is that the small band-gap materials (e.g., InGaAs or Ge) necessary to detect low-energy photons exhibit higher dark counts and higher multiplication noise compared to materials like silicon. To overcome these historical problems APDs were designed and fabricated using separate absorption and multiplication (SAM) regions. The absorption regions used (InGaAs or Ge) to leverage these materials 1550 nm sensitivity. Geiger mode detection was chosen to circumvent gain noise issues in the III-V and Ge multiplication regions, while a novel Ge/Si device was built to examine the utility of transferring photoelectrons in a silicon multiplication region. Silicon is known to have very good analog and GM multiplication properties. The proposed devices represented a high-risk for high-reward approach. Therefore one primary goal of this work was to experimentally resolve uncertainty about the novel APD structures. This work specifically examined three different designs. An InGaAs/InAlAs Geiger mode (GM) structure was proposed for the superior multiplication properties of the InAlAs. The hypothesis to be tested in this structure was whether InAlAs really presented an advantage in GM. A Ge/Si SAM was proposed representing the best possible multiplication material (i.e., silicon), however, significant uncertainty existed about both the Ge material quality and the ability to transfer photoelectrons across the Ge/Si interface. Finally a third pure germanium GM structure was proposed because bulk germanium has been reported to have better dark count properties. However, significant

  15. Topography improvements in MEMS DMs for high-contrast, high-resolution imaging Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop and demonstrate an innovative microfabrication process to substantially improve the surface quality achievable in high-resolution...

  16. Reflections from a Creative Community-Based Participatory Research Project Exploring Health and Body Image with First Nations Girls

    Directory of Open Access Journals (Sweden)

    Jennifer M. Shea PhD

    2013-02-01

    Full Text Available In Canada, Aboriginal peoples often experience a multitude of inequalities when compared with the general population, particularly in relation to health (e.g., increased incidence of diabetes. These inequalities are rooted in a negative history of colonization. Decolonizing methodologies recognize these realities and aim to shift the focus from communities being researched to being collaborative partners in the research process. This article describes a qualitative community-based participatory research project focused on health and body image with First Nations girls in a Tribal Council region in Western Canada. We discuss our project design and the incorporation of creative methods (e.g., photovoice to foster integration and collaboration as related to decolonizing methodology principles. This article is both descriptive and reflective as it summarizes our project and discusses lessons learned from the process, integrating evaluations from the participating girls as well as our reflections as researchers.

  17. Three-dimensional atomic models from a single projection using Z-contrast imaging: verification by electron tomography and opportunities.

    Science.gov (United States)

    De Backer, A; Jones, L; Lobato, I; Altantzis, T; Goris, B; Nellist, P D; Bals, S; Van Aert, S

    2017-06-29

    In order to fully exploit structure-property relations of nanomaterials, three-dimensional (3D) characterization at the atomic scale is often required. In recent years, the resolution of electron tomography has reached the atomic scale. However, such tomography typically requires several projection images demanding substantial electron dose. A newly developed alternative circumvents this by counting the number of atoms across a single projection. These atom counts can be used to create an initial atomic model with which an energy minimization can be applied to obtain a relaxed 3D reconstruction of the nanoparticle. Here, we compare, at the atomic scale, this single projection reconstruction approach with tomography and find an excellent agreement. This new approach allows for the characterization of beam-sensitive materials or where the acquisition of a tilt series is impossible. As an example, the utility is illustrated by the 3D atomic scale characterization of a nanodumbbell on an in situ heating holder of limited tilt range.

  18. The utility of three-dimensional optical projection tomography in nerve injection injury imaging

    Czech Academy of Sciences Publication Activity Database

    Cvetko, E.; Čapek, Martin; Damjanovska, M.; Reina, M. A.; Eržen, I.; Stopar-Pintarič, T.

    2015-01-01

    Roč. 70, č. 8 (2015), s. 939-947 ISSN 0003-2409 R&D Projects: GA ČR(CZ) GA13-12412S; GA MŠk(CZ) LH13028 Institutional support: RVO:67985823 Keywords : optical projection tomography * 3D nerve visualization * nerve disruption Subject RIV: EA - Cell Biology Impact factor: 3.794, year: 2015

  19. The Lunar Student Imaging Project (LSIP): Bringing the Excitement of Lunar Exploration to Students Using LRO Mission Data

    Science.gov (United States)

    Taylor, W. L.; Roberts, D.; Burnham, R.; Robinson, M. S.

    2009-12-01

    In June 2009, NASA launched the Lunar Reconnaissance Orbiter (LRO) - the first mission in NASA's Vision for Space Exploration, a plan to return to the Moon and then to travel to Mars and beyond. LRO is equipped with seven instruments including the Lunar Reconnaissance Orbiter Camera (LROC), a system of two narrow-angle cameras and one wide-angle camera, controlled by scientists in the School of Earth and Space Exploration at Arizona State University. The orbiter will have a one-year primary mission in a 50 km polar orbit. The measurements from LROC will uncover much-needed information about potential landing sites and will help generate a meter scale map of the lunar surface. With support from NASA Goddard Space Flight Center, the LROC Science Operations Center and the ASU Mars Education Program, have partnered to develop an inquiry-based student program, the Lunar Student Imaging Project (LSIP). Based on the nationally recognized, Mars Student Imaging Project (MSIP), LSIP uses cutting-edge NASA content and remote sensing data to involve students in authentic lunar exploration. This program offers students (grades 5-14) immersive experiences where they can: 1) target images of the lunar surface, 2) interact with NASA planetary scientists, mission engineers and educators, and 3) gain access to NASA curricula and materials developed to enhance STEM learning. Using a project based learning model, students drive their own research and learn first hand what it’s like to do real planetary science. The LSIP curriculum contains a resource manual and program guide (including lunar feature identification charts, classroom posters, and lunar exploration time line) and a series of activities covering image analysis, relative age dating and planetary comparisons. LSIP will be based upon the well-tested MSIP model, and will encompass onsite as well as distance learning components.

  20. System and technique for retrieving depth information about a surface by projecting a composite image of modulated light patterns

    Science.gov (United States)

    Hassebrook, Laurence G. (Inventor); Lau, Daniel L. (Inventor); Guan, Chun (Inventor)

    2010-01-01

    A technique, associated system and program code, for retrieving depth information about at least one surface of an object, such as an anatomical feature. Core features include: projecting a composite image comprising a plurality of modulated structured light patterns, at the anatomical feature; capturing an image reflected from the surface; and recovering pattern information from the reflected image, for each of the modulated structured light patterns. Pattern information is preferably recovered for each modulated structured light pattern used to create the composite, by performing a demodulation of the reflected image. Reconstruction of the surface can be accomplished by using depth information from the recovered patterns to produce a depth map/mapping thereof. Each signal waveform used for the modulation of a respective structured light pattern, is distinct from each of the other signal waveforms used for the modulation of other structured light patterns of a composite image; these signal waveforms may be selected from suitable types in any combination of distinct signal waveforms, provided the waveforms used are uncorrelated with respect to each other. The depth map/mapping to be utilized in a host of applications, for example: displaying a 3-D view of the object; virtual reality user-interaction interface with a computerized device; face--or other animal feature or inanimate object--recognition and comparison techniques for security or identification purposes; and 3-D video teleconferencing/telecollaboration.

  1. Deployment of a Prototype Plant GFP Imager at the Arthur Clarke Mars Greenhouse of the Haughton Mars Project

    Directory of Open Access Journals (Sweden)

    Robert J. Ferl

    2008-04-01

    Full Text Available The use of engineered plants as biosensors has made elegant strides in the past decades, providing keen insights into the health of plants in general and particularly in the nature and cellular location of stress responses. However, most of the analytical procedures involve laboratory examination of the biosensor plants. With the advent of the green fluorescence protein (GFP as a biosensor molecule, it became at least theoretically possible for analyses of gene expression to occur telemetrically, with the gene expression information of the plant delivered to the investigator over large distances simply as properly processed fluorescence images. Spaceflight and other extraterrestrial environments provide unique challenges to plant life, challenges that often require changes at the gene expression level to accommodate adaptation and survival. Having previously deployed transgenic plant biosensors to evaluate responses to orbital spaceflight, we wished to develop the plants and especially the imaging devices required to conduct such experiments robotically, without operator intervention, within extraterrestrial environments. This requires the development of an autonomous and remotely operated plant GFP imaging system and concomitant development of the communications infrastructure to manage dataflow from the imaging device. Here we report the results of deploying a prototype GFP imaging system within the Arthur Clarke Mars Greenhouse (ACMG an autonomously operated greenhouse located within the Haughton Mars Project in the Canadian High Arctic. Results both demonstrate the applicability of the fundamental GFP biosensor technology and highlight the difficulties in collecting and managing telemetric data from challenging deployment environments.

  2. Hyperspectral Imaging for Presymptomatic Detection of Tobacco Disease with Successive Projections Algorithm and Machine-learning Classifiers.

    Science.gov (United States)

    Zhu, Hongyan; Chu, Bingquan; Zhang, Chu; Liu, Fei; Jiang, Linjun; He, Yong

    2017-06-23

    We investigated the feasibility and potentiality of presymptomatic detection of tobacco disease using hyperspectral imaging, combined with the variable selection method and machine-learning classifiers. Images from healthy and TMV-infected leaves with 2, 4, and 6 days post infection were acquired by a pushbroom hyperspectral reflectance imaging system covering the spectral range of 380-1023 nm. Successive projections algorithm was evaluated for effective wavelengths (EWs) selection. Four texture features, including contrast, correlation, entropy, and homogeneity were extracted according to grey-level co-occurrence matrix (GLCM). Additionally, different machine-learning algorithms were developed and compared to detect and classify disease stages with EWs, texture features and data fusion respectively. The performance of chemometric models with data fusion manifested better results with classification accuracies of calibration and prediction all above 80% than those only using EWs or texture features; the accuracies were up to 95% employing back propagation neural network (BPNN), extreme learning machine (ELM), and least squares support vector machine (LS-SVM) models. Hence, hyperspectral imaging has the potential as a fast and non-invasive method to identify infected leaves in a short period of time (i.e. 48 h) in comparison to the reference images (5 days for visible symptoms of infection, 11 days for typical symptoms).

  3. 3D palmprint and hand imaging system based on full-field composite color sinusoidal fringe projection technique.

    Science.gov (United States)

    Zhang, Zonghua; Huang, Shujun; Xu, Yongjia; Chen, Chao; Zhao, Yan; Gao, Nan; Xiao, Yanjun

    2013-09-01

    Palmprint and hand shape, as two kinds of important biometric characteristics, have been widely studied and applied to human identity recognition. The existing research is based mainly on 2D images, which lose the third-dimensional information. The biological features extracted from 2D images are distorted by pressure and rolling, so the subsequent feature matching and recognition are inaccurate. This paper presents a method to acquire accurate 3D shapes of palmprint and hand by projecting full-field composite color sinusoidal fringe patterns and the corresponding color texture information. A 3D imaging system is designed to capture and process the full-field composite color fringe patterns on hand surface. Composite color fringe patterns having the optimum three fringe numbers are generated by software and projected onto the surface of human hand by a digital light processing projector. From another viewpoint, a color CCD camera captures the deformed fringe patterns and saves them for postprocessing. After compensating for the cross talk and chromatic aberration between color channels, three fringe patterns are extracted from three color channels of a captured composite color image. Wrapped phase information can be calculated from the sinusoidal fringe patterns with high precision. At the same time, the absolute phase of each pixel is determined by the optimum three-fringe selection method. After building up the relationship between absolute phase map and 3D shape data, the 3D palmprint and hand are obtained. Color texture information can be directly captured or demodulated from the captured composite fringe pattern images. Experimental results show that the proposed method and system can yield accurate 3D shape and color texture information of the palmprint and hand shape.

  4. Image quality in thoracic 4D cone-beam CT: A sensitivity analysis of respiratory signal, binning method, reconstruction algorithm, and projection angular spacing

    International Nuclear Information System (INIS)

    Shieh, Chun-Chien; Kipritidis, John; O’Brien, Ricky T.; Keall, Paul J.; Kuncic, Zdenka

    2014-01-01

    Purpose: Respiratory signal, binning method, and reconstruction algorithm are three major controllable factors affecting image quality in thoracic 4D cone-beam CT (4D-CBCT), which is widely used in image guided radiotherapy (IGRT). Previous studies have investigated each of these factors individually, but no integrated sensitivity analysis has been performed. In addition, projection angular spacing is also a key factor in reconstruction, but how it affects image quality is not obvious. An investigation of the impacts of these four factors on image quality can help determine the most effective strategy in improving 4D-CBCT for IGRT. Methods: Fourteen 4D-CBCT patient projection datasets with various respiratory motion features were reconstructed with the following controllable factors: (i) respiratory signal (real-time position management, projection image intensity analysis, or fiducial marker tracking), (ii) binning method (phase, displacement, or equal-projection-density displacement binning), and (iii) reconstruction algorithm [Feldkamp–Davis–Kress (FDK), McKinnon–Bates (MKB), or adaptive-steepest-descent projection-onto-convex-sets (ASD-POCS)]. The image quality was quantified using signal-to-noise ratio (SNR), contrast-to-noise ratio, and edge-response width in order to assess noise/streaking and blur. The SNR values were also analyzed with respect to the maximum, mean, and root-mean-squared-error (RMSE) projection angular spacing to investigate how projection angular spacing affects image quality. Results: The choice of respiratory signals was found to have no significant impact on image quality. Displacement-based binning was found to be less prone to motion artifacts compared to phase binning in more than half of the cases, but was shown to suffer from large interbin image quality variation and large projection angular gaps. Both MKB and ASD-POCS resulted in noticeably improved image quality almost 100% of the time relative to FDK. In addition, SNR

  5. In-Situ / In-Flight Detection of Fluorescent Proteins Using Imaging Spectroscopy Sensors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposal addresses technologies relevant to NASA's new Vision for Space Explorations in the areas of robotics, teleoperations, and macro and micro imaging...

  6. High Spectral Resolution, High Cadence, Imaging X-ray Microcalorimeters for Solar Physics - Phase 2 Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcalorimeter x-ray instruments are non-dispersive, high spectral resolution, broad-band, high cadence imaging spectrometers. We have been developing these...

  7. US Participation in the Solar Orbiter Multi Element Telescope for Imaging and Spectroscopy (METIS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Multi Element Telescope for Imaging and Spectroscopy, METIS, investigation has been conceived to perform off-limb and near-Sun coronagraphy and is motivated by...

  8. Thin Silicon Detector Technology for Use in Imaging Solar ENAs Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Top Level Objective: To enable capabilities for imaging and spectral measurements of energetic neutral hydrogen atoms (ENAs) produced with energies ∼1MeV/nuc in...

  9. An Ultra-Compact High-Definition Hyperspectral Imaging System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a powerful Ultra-Compact High-Definition Hyperspectral Imaging System (UC-HDHIS) for UAV deployment. UC-HDHIS concurrently acquires pushbroom...

  10. Aircraft Based Imaging Probe for the Study of Icing Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Icing environments are of great concern in commercial and military aviation. An aircraft-based, imaging probe is being proposed for the reliable and accurate...

  11. Images

    Data.gov (United States)

    National Aeronautics and Space Administration — Images for the website main pages and all configurations. The upload and access points for the other images are: Website Template RSW images BSCW Images HIRENASD...

  12. Virtual autopsy using imaging: bridging radiologic and forensic sciences. A review of the Virtopsy and similar projects

    International Nuclear Information System (INIS)

    Bolliger, Stephan A.; Thali, Michael J.; Ross, Steffen; Buck, Ursula; Naether, Silvio; Vock, Peter

    2008-01-01

    The transdisciplinary research project Virtopsy is dedicated to implementing modern imaging techniques into forensic medicine and pathology in order to augment current examination techniques or even to offer alternative methods. Our project relies on three pillars: three-dimensional (3D) surface scanning for the documentation of body surfaces, and both multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) to visualise the internal body. Three-dimensional surface scanning has delivered remarkable results in the past in the 3D documentation of patterned injuries and of objects of forensic interest as well as whole crime scenes. Imaging of the interior of corpses is performed using MSCT and/or MRI. MRI, in addition, is also well suited to the examination of surviving victims of assault, especially choking, and helps visualise internal injuries not seen at external examination of the victim. Apart from the accuracy and three-dimensionality that conventional documentations lack, these techniques allow for the re-examination of the corpse and the crime scene even decades later, after burial of the corpse and liberation of the crime scene. We believe that this virtual, non-invasive or minimally invasive approach will improve forensic medicine in the near future. (orig.)

  13. Virtual autopsy using imaging: bridging radiologic and forensic sciences. A review of the Virtopsy and similar projects.

    Science.gov (United States)

    Bolliger, Stephan A; Thali, Michael J; Ross, Steffen; Buck, Ursula; Naether, Silvio; Vock, Peter

    2008-02-01

    The transdisciplinary research project Virtopsy is dedicated to implementing modern imaging techniques into forensic medicine and pathology in order to augment current examination techniques or even to offer alternative methods. Our project relies on three pillars: three-dimensional (3D) surface scanning for the documentation of body surfaces, and both multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) to visualise the internal body. Three-dimensional surface scanning has delivered remarkable results in the past in the 3D documentation of patterned injuries and of objects of forensic interest as well as whole crime scenes. Imaging of the interior of corpses is performed using MSCT and/or MRI. MRI, in addition, is also well suited to the examination of surviving victims of assault, especially choking, and helps visualise internal injuries not seen at external examination of the victim. Apart from the accuracy and three-dimensionality that conventional documentations lack, these techniques allow for the re-examination of the corpse and the crime scene even decades later, after burial of the corpse and liberation of the crime scene. We believe that this virtual, non-invasive or minimally invasive approach will improve forensic medicine in the near future.

  14. The myImageAnalysis project: a web-based application for high-content screening.

    Science.gov (United States)

    Szafran, Adam T; Mancini, Michael A

    2014-01-01

    A major challenge faced by screening centers developing image-based assays is the wide range of assays needed compared to the limited resources that are available to effectively analyze and manage them. To overcome this limitation, we have developed the web-based myImageAnalysis (mIA) application, integrated with an open database connectivity compliant database and powered by Pipeline Pilot (PLP) that incorporates dataset tracking, scheduling and archiving, image analysis, and data reporting. For system administrators, mIA provides automated methods for managing and archiving data. For the biologist, this application allows those without any programming or image analysis experience to quickly develop, validate, and share results of complex image-based assays. Further, the structure of the application within PLP allows those with experience in PLP programming to easily add additional analysis tools as required. The tools within mIA allow users to assess basic (cell count, protein per cell, protein subcellular localization) and more advanced (engineered cell lines analysis, cell toxicity) biological image-based assays that employ advanced statistics and provides key assay performance metrics.

  15. Reduce blurring and distortion in a projection type virtual image display using integrated small optics

    Science.gov (United States)

    Hasegawa, Tatsuya; Yendo, Tomohiro

    2015-03-01

    Head Up Display (HUD) is being applied to automobile. HUD displays information as far virtual image on the windshield. Existing HUD usually displays planar information. If the image corresponding to scenery on the road like Augmented Reality (AR) is displayed on the HUD, driver can efficiently get the information. To actualize this, HUD covering large viewing field is needed. However existing HUD cannot cover large viewing field. Therefore we have proposed system consisting of projector and many small diameter convex lenses. However observed virtual image has blurring and distortion . In this paper, we propose two methods to reduce blurring and distortion of images. First, to reduce blurring of images, distance between each of screen and lens comprised in lens array is adjusted. We inferred from the more distant the lens from center of the array is more blurred that the cause of blurring is curvature of field of lens in the array. Second, to avoid distortion of images, each lens in the array is curved spherically. We inferred from the more distant the lens from center of the array is more distorted that the cause of distortion is incident angle of ray. We confirmed effectiveness of both methods.

  16. High-dynamic range image projection using an auxiliary MEMS mirror array.

    Science.gov (United States)

    Hoskinson, Reynald; Stoeber, Boris

    2008-05-12

    We introduce a new concept to improve the contrast and peak brightness of conventional data projectors. Our method provides a non-homogenous light source by dynamically directing fractions of the light from the projector lamp before it reaches the display mechanism. This will supply more light to the areas that need it most, at the expense of the darker parts of the image. In effect, this method will produce a low resolution version of the image onto the image-forming element. To manipulate the light in this manner, we propose using an intermediate array of microelectromechanical system (MEMS) mirrors. By directing the light away from the dark parts earlier in the display chain, the amount of light that needs to be blocked will be reduced, thus decreasing the black level of the final image. Moreover, the ability to dynamically allocate more light to the bright parts of the image will allow for peak brightness higher than the average maximum brightness of display.

  17. Reconstruction of 4-D dynamic SPECT images from inconsistent projections using a Spline initialized FADS algorithm (SIFADS).

    Science.gov (United States)

    Abdalah, Mahmoud; Boutchko, Rostyslav; Mitra, Debasis; Gullberg, Grant T

    2015-01-01

    In this paper, we propose and validate an algorithm of extracting voxel-by-voxel time activity curves directly from inconsistent projections applied in dynamic cardiac SPECT. The algorithm was derived based on factor analysis of dynamic structures (FADS) approach and imposes prior information by applying several regularization functions with adaptively changing relative weighting. The anatomical information of the imaged subject was used to apply the proposed regularization functions adaptively in the spatial domain. The algorithm performance is validated by reconstructing dynamic datasets simulated using the NCAT phantom with a range of different input tissue time-activity curves. The results are compared to the spline-based and FADS methods. The validated algorithm is then applied to reconstruct pre-clinical cardiac SPECT data from canine and murine subjects. Images, generated from both simulated and experimentally acquired data confirm the ability of the new algorithm to solve the inverse problem of dynamic SPECT with slow gantry rotation.

  18. Reconstruction of tomographic images from projections of a small number of views by means of mathematical programming

    International Nuclear Information System (INIS)

    Kobayashi, Fujio; Yamaguchi, Shoichiro

    1985-01-01

    Fundamental studies have been made on the application of mathematical programming to the reconstruction of tomographic images from projections of a small number of views without requiring any circular symmetry nor periodicity. Linear programming and quadratic programming were applied to minimize the quadratic sum of the residue and to finally obtain optimized reconstruction images. The mathematical algorithms were verified by the method of computer simulation, and the relationship between the number of picture elements and the number of iterations necessary for convergence was also investigated. The methods of linear programming and quadratic programming require fairly simple mathematical procedures, and strict solutions can be obtained within a finite number of iterations. Their only draw back is the requirement of a large quantity of computer memory. But this problem will be desolved by the advent of large fast memory devices in the near future. (Aoki, K.)

  19. Pulse X-ray device for stereo imaging and few-projection tomography of explosive and fast processes

    Science.gov (United States)

    Palchikov, E. I.; Dolgikh, A. V.; Klypin, V. V.; Krasnikov, I. Y.; Ryabchun, A. M.

    2017-10-01

    This paper describes the operation principles and design features of the device for single pulse X-raying of explosive and high-speed processes, developed on the basis of a Tesla transformer with lumped secondary capacitor bank. The circuit with the lumped capacitor bank allows transferring a greater amount of energy to the discharge circuit as compared with the Marks-surge generator for more effective operation with remote X-ray tubes connected by coaxial cables. The device equipped with multiple X-ray tubes provides simultaneous X-raying of extended or spaced objects, stereo imaging, or few-projection tomography.

  20. 3D Prior Image Constrained Projection Completion for X-ray CT Metal Artifact Reduction

    NARCIS (Netherlands)

    Mehranian, Abolfazl; Ay, Mohammad Reza; Rahmim, Arman; Zaidi, Habib

    2013-01-01

    The presence of metallic implants in the body of patients undergoing X-ray computed tomography (CT) examinations often results insevere streaking artifacts that degrade image quality. In this work, we propose a new metal artifact reduction (MAR) algorithm for 2D fan-beam and 3D cone-beam CT based on

  1. Neutron imaging: A non-destructive tool for materials testing. Report of a coordinated research project 2003-2006

    International Nuclear Information System (INIS)

    2008-09-01

    The enhancement of utilization of research reactors is one of the major objectives of the IAEA's project on Effective Utilization of Research Reactors. In particular, the improvement of existing installations for neutron imaging and the effective utilization of such facilities are intended. From the experience of Type A facilities, it is obvious that some investment is required to come from simple neutron imaging methods (film, track-etch foils) to the more enhanced ones. Related to the installation and operation of the whole reactor system, the volume of the investment for an imaging device is minor. Also compared to the installations for neutron scattering research, neutron imaging systems are relatively cheap, but very efficient in the use of the neutrons. Therefore, one of the aims of the CRP was to look for adapted solutions for the individual reactor installation and beam line. Specific Research Objectives: To optimize the neutron beams for imaging purpose using modern simulation techniques; To enhance the beam intensity using modern layout principles, neutron optics, like focusing and beam guides and filters; To develop a standardized, low cost, neutron image grabber and analyzer for efficient data collection that can be used with low intensity sources; To improve signal processing techniques used in neutron imaging applications. Expected Research Outputs: Neutron radiography is used at research reactor centres in many Member States, but the facilities are not optimized for attractive potential applications. This fact has been brought out at various discussion meetings. The CRP is aimed at improving the design of beam lines in terms of neutron collimation and intensity; Improvements in resolution are normally achieved at a cost in intensity. For an instrument exhibiting good resolution, one needs to employ a fast counting system. It is proposed to work along these lines to develop an optimised detection system. Many facilities, at present, have small CCD

  2. Induced Polarization with Electromagnetic Coupling: 3D Spectral Imaging Theory, EMSP Project No. 73836

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, F. Dale; Sogade, John

    2004-12-14

    This project was designed as a broad foundational study of spectral induced polarization (SIP) for characterization of contaminated sites. It encompassed laboratory studies of the effects of chemistry on induced polarization, development of 3D forward modeling and inversion codes, and investigations of inductive and capacitive coupling problems. In the laboratory part of the project a physico-chemical model developed in this project was used to invert laboratory IP spectra for the grain size and the effective grain size distribution of the sedimentary rocks as well as the formation factor, porosity, specific surface area, and the apparent fractal dimension. Furthermore, it was established that the IP response changed with the solution chemistry, the concentration of a given solution chemistry, valence of the constituent ions, and ionic radius. In the field part of the project, a 3D complex forward and inverse model was developed. It was used to process data acquired at two frequencies (1/16 Hz and 1/ 4Hz) in a cross-borehole configuration at the A-14 outfall area of the Savannah River Site (SRS) during March 2003 and June 2004. The chosen SRS site was contaminated with Tetrachloroethylene (TCE) and Trichloroethylene (PCE) that were disposed in this area for several decades till the 1980s. The imaginary conductivity produced from the inverted 2003 data correlated very well with the log10 (PCE) concentration derived from point sampling at 1 ft spacing in five ground-truth boreholes drilled after the data acquisition. The equivalent result for the 2004 data revealed that there were significant contaminant movements during the period March 2003 and June 2004, probably related to ground-truth activities and nearby remediation activities. Therefore SIP was successfully used to develop conceptual models of volume distributions of PCE/TCE contamination. In addition, the project developed non-polarizing electrodes that can be deployed in boreholes for years. A total of 28

  3. Projections onto Convex Sets Super-Resolution Reconstruction Based on Point Spread Function Estimation of Low-Resolution Remote Sensing Images.

    Science.gov (United States)

    Fan, Chong; Wu, Chaoyun; Li, Grand; Ma, Jun

    2017-02-13

    To solve the problem on inaccuracy when estimating the point spread function (PSF) of the ideal original image in traditional projection onto convex set (POCS) super-resolution (SR) reconstruction, this paper presents an improved POCS SR algorithm based on PSF estimation of low-resolution (LR) remote sensing images. The proposed algorithm can improve the spatial resolution of the image and benefit agricultural crop visual interpolation. The PSF of the highresolution (HR) image is unknown in reality. Therefore, analysis of the relationship between the PSF of the HR image and the PSF of the LR image is important to estimate the PSF of the HR image by using multiple LR images. In this study, the linear relationship between the PSFs of the HR and LR images can be proven. In addition, the novel slant knife-edge method is employed, which can improve the accuracy of the PSF estimation of LR images. Finally, the proposed method is applied to reconstruct airborne digital sensor 40 (ADS40) three-line array images and the overlapped areas of two adjacent GF-2 images by embedding the estimated PSF of the HR image to the original POCS SR algorithm. Experimental results show that the proposed method yields higher quality of reconstructed images than that produced by the blind SR method and the bicubic interpolation method.

  4. Projections onto Convex Sets Super-Resolution Reconstruction Based on Point Spread Function Estimation of Low-Resolution Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Chong Fan

    2017-02-01

    Full Text Available To solve the problem on inaccuracy when estimating the point spread function (PSF of the ideal original image in traditional projection onto convex set (POCS super-resolution (SR reconstruction, this paper presents an improved POCS SR algorithm based on PSF estimation of low-resolution (LR remote sensing images. The proposed algorithm can improve the spatial resolution of the image and benefit agricultural crop visual interpolation. The PSF of the highresolution (HR image is unknown in reality. Therefore, analysis of the relationship between the PSF of the HR image and the PSF of the LR image is important to estimate the PSF of the HR image by using multiple LR images. In this study, the linear relationship between the PSFs of the HR and LR images can be proven. In addition, the novel slant knife-edge method is employed, which can improve the accuracy of the PSF estimation of LR images. Finally, the proposed method is applied to reconstruct airborne digital sensor 40 (ADS40 three-line array images and the overlapped areas of two adjacent GF-2 images by embedding the estimated PSF of the HR image to the original POCS SR algorithm. Experimental results show that the proposed method yields higher quality of reconstructed images than that produced by the blind SR method and the bicubic interpolation method.

  5. Breast tissue image classification based on Semi-supervised Locality Discriminant Projection with Kernels.

    Science.gov (United States)

    Li, Jun-Bao; Yu, Yang; Yang, Zhi-Ming; Tang, Lin-Lin

    2012-10-01

    Breast tissue classification is an important and effective way for computer aided diagnosis of breast cancer. We present Semi-supervised Locality Discriminant Projections with Kernels for breast cancer classification. The contributions of this work lie in: 1) Semi-supervised learning is used into Locality Preserving Projections (LPP) to enhance its performance using side-information together with the unlabelled training samples, while current algorithms only consider the side-information but ignoring the unlabeled training samples. 2) Kernel trick is applied into Semi-supervised LPP to improve its ability in the nonlinear classification. 3) The framework of breast cancer classification with Semi-supervised LPP with kernels is presented. Many experiments are implemented on four breast tissue databases to testify and evaluate the feasibility and affectivity of the proposed scheme.

  6. Magnetic resonance imaging: project planning and management of a superconductive M.R.I. installation

    International Nuclear Information System (INIS)

    Condon, P.M.; Robertson, A.R.

    1989-01-01

    The planning and installation of a Superconductive Magnetic Resonance Imaging installation at the Royal Adelaide Hospital, Adelaide, South Australia is described. Tender specification, assessment of offers via criteria weighted analysis of technical and economic factors and the final recommendation for a 1.0 Tesla unit are discussed. Building and installation considerations are noted including fringe field effects, magnetic shielding, radiofrequency shielding, cryogens, metallic screening and specific considerations in the Magnet room. 9 refs., 7 figs

  7. MAD ADAPTIVE OPTICS IMAGING OF HIGH-LUMINOSITY QUASARS: A PILOT PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Liuzzo, E. [Osservatorio di Radioastronomia, INAF, via Gobetti 101, I-40129 Bologna (Italy); Falomo, R.; Paiano, S.; Baruffolo, A.; Farinato, J.; Moretti, A.; Ragazzoni, R. [Osservatorio Astronomico di Padova, INAF, vicolo dell’Osservatorio 5, I-35122 Padova (Italy); Treves, A. [Università dell’Insubria (Como) (Italy); Uslenghi, M. [INAF-IASF, via E. Bassini 15, I-20133 Milano (Italy); Arcidiacono, C.; Diolaiti, E.; Lombini, M. [Osservatorio Astronomico di Bologna, INAF, Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Brast, R. [Dipartimento di Fisica e Astronomia, Università di Bologna, Via Irnerio, 46, I-40126, Bologna (Italy); Donaldson, R.; Kolb, J.; Marchetti, E.; Tordo, S., E-mail: liuzzo@ira.inaf.it [European Southern Observatory, Karl-Schwarschild-Strasse 2, D-85748 Garching bei München (Germany)

    2016-08-01

    We present near-IR images of five luminous quasars at z ∼ 2 and one at z ∼ 4 obtained with an experimental adaptive optics (AO) instrument at the European Southern Observatory Very Large Telescope. The observations are part of a program aimed at demonstrating the capabilities of multi-conjugated adaptive optics imaging combined with the use of natural guide stars for high spatial resolution studies on large telescopes. The observations were mostly obtained under poor seeing conditions but in two cases. In spite of these nonoptimal conditions, the resulting images of point sources have cores of FWHM ∼ 0.2 arcsec. We are able to characterize the host galaxy properties for two sources and set stringent upper limits to the galaxy luminosity for the others. We also report on the expected capabilities for investigating the host galaxies of distant quasars with AO systems coupled with future Extremely Large Telescopes. Detailed simulations show that it will be possible to characterize compact (2–3 kpc) quasar host galaxies for quasi-stellar objects at z = 2 with nucleus K -magnitude spanning from 15 to 20 (corresponding to absolute magnitude −31 to −26) and host galaxies that are 4 mag fainter than their nuclei.

  8. Black Heart Detection in White Radish by Hyperspectral Transmittance Imaging Combined with Chemometric Analysis and a Successive Projections Algorithm

    Directory of Open Access Journals (Sweden)

    Dajie Song

    2016-09-01

    Full Text Available Radishes with black hearts will lose edible value and cause food safety problems, so it is important to detect and remove the defective ones before processing and consumption. A hyperspectral transmittance imaging system with 420 wavelengths was developed to capture images from white radishes. A successive-projections algorithm (SPA was applied with 10 wavelengths selected to distinguish defective radishes with black hearts from normal samples. Pearson linear correlation coefficients were calculated to further refine the set of wavelengths with 4 wavelengths determined. Four chemometric classifiers were developed for classification of normal and defective radishes, using 420, 10 and 4 wavelengths as input variables. The overall classifying accuracy based on the four classifiers were 95.6%–100%. The highest classification with 100% was obtained with a back propagation artificial neural network (BPANN for both calibration and prediction using 420 and 10 wavelengths. Overall accuracies of 98.4% and 97.8% were obtained for calibration and prediction, respectively, with Fisher's linear discriminant analysis (FLDA based on 4 wavelengths, and was better than the other three classifiers. This indicated that the developed hyperspectral transmittance imaging was suitable for black heart detection in white radishes with the optimal wavelengths, which has potential for fast on-line discrimination before food processing or reaching storage shelves.

  9. THE PERIGEO PROJECT: INERTIAL AND IMAGING SENSORS PROCESSING, INTEGRATION AND VALIDATION ON UAV PLATFORMS FOR SPACE NAVIGATION

    Directory of Open Access Journals (Sweden)

    P. Molina

    2014-03-01

    Full Text Available The PERIGEO R&D project aims at developing, testing and validating algorithms and/or methods for space missions in various field of research. This paper focuses in one of the scenarios considered in PERIGEO: navigation for atmospheric flights. Space missions heavily rely on navigation to reach success, and autonomy of on-board navigation systems and sensors is desired to reach new frontiers of space exploration. From the technology side, optical frame cameras, LiDAR and inertial technologies are selected to cover the requirements of such missions. From the processing side, image processing techniques are developed for vision-based relative and absolute navigation, based on point extraction and matching from camera images, and crater detection and matching in camera and LiDAR images. The current paper addresses the challenges of space navigation, presents the current developments and preliminary results, and describes payload elements to be integrated in an Unmanned Aerial Vehicle (UAV for in-flight testing of systems and algorithms. Again, UAVs are key enablers of scientific capabilities, in this case, to bridge the gap between laboratory simulation and expensive, real space missions.

  10. Fast 3D ultrashort echo-time spiral projection imaging using golden-angle: A flexible protocol for in vivo mouse imaging at high magnetic field.

    Science.gov (United States)

    Castets, Charles R; Lefrançois, William; Wecker, Didier; Ribot, Emeline J; Trotier, Aurélien J; Thiaudière, Eric; Franconi, Jean-Michel; Miraux, Sylvain

    2017-05-01

    To develop a fast three-dimensional (3D) k-space encoding method based on spiral projection imaging (SPI) with an interleaved golden-angle approach and to validate this novel sequence on small animal models. A disk-like trajectory, in which each disk contained spirals, was developed. The 3D encoding was performed by tilting the disks with a golden angle. The sharpness was first calculated at different T2* values. Then, the sharpness was measured on phantom using variable undersampling ratios. Finally, the sampling method was validated by whole brain time-of-flight angiography and ultrasmall superparamagnetic iron oxide (USPIO) enhanced free-breathing liver angiography on mouse. The in vitro results demonstrated the robustness of the method for short T2* and high undersampling ratios. In vivo experiments showed the ability to properly detect small vessels in the brain with an acquisition time shorter than 1 min. Free-breathing mice liver angiography showed the insensitivity of this protocol toward motions and flow artifacts, and enabled the visualization of liver motion during breathing. The method implemented here allowed fast 3D k-space sampling with a high undersampling ratio. Combining the advantages of center-out spirals with the flexibility of the golden angle approach could have major implications for real-time imaging. Magn Reson Med 77:1831-1840, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  11. Synchrotron microCT imaging of soft tissue in juvenile zebrafish reveals retinotectal projections

    Science.gov (United States)

    Xin, Xuying; Clark, Darin; Ang, Khai Chung; van Rossum, Damian B.; Copper, Jean; Xiao, Xianghui; La Riviere, Patrick J.; Cheng, Keith C.

    2017-02-01

    Biomedical research and clinical diagnosis would benefit greatly from full volume determinations of anatomical phenotype. Comprehensive tools for morphological phenotyping are central for the emerging field of phenomics, which requires high-throughput, systematic, accurate, and reproducible data collection from organisms affected by genetic, disease, or environmental variables. Theoretically, complete anatomical phenotyping requires the assessment of every cell type in the whole organism, but this ideal is presently untenable due to the lack of an unbiased 3D imaging method that allows histopathological assessment of any cell type despite optical opacity. Histopathology, the current clinical standard for diagnostic phenotyping, involves the microscopic study of tissue sections to assess qualitative aspects of tissue architecture, disease mechanisms, and physiological state. However, quantitative features of tissue architecture such as cellular composition and cell counting in tissue volumes can only be approximated due to characteristics of tissue sectioning, including incomplete sampling and the constraints of 2D imaging of 5 micron thick tissue slabs. We have used a small, vertebrate organism, the zebrafish, to test the potential of microCT for systematic macroscopic and microscopic morphological phenotyping. While cell resolution is routinely achieved using methods such as light sheet fluorescence microscopy and optical tomography, these methods do not provide the pancellular perspective characteristic of histology, and are constrained by the limited penetration of visible light through pigmented and opaque specimens, as characterizes zebrafish juveniles. Here, we provide an example of neuroanatomy that can be studied by microCT of stained soft tissue at 1.43 micron isotropic voxel resolution. We conclude that synchrotron microCT is a form of 3D imaging that may potentially be adopted towards more reproducible, large-scale, morphological phenotyping of optically

  12. Astro-imaging projects for amateur astronomers a maker’s guide

    CERN Document Server

    Chung, Jim

    2015-01-01

    This is the must-have guide for all amateur astronomers who double as makers, doers, tinkerers, problem-solvers, and inventors. In a world where an amateur astronomy habit can easily run into the many thousands of dollars, it is still possible for practitioners to get high-quality results and equipment on a budget by utilizing DIY techniques. Surprisingly, it's not that hard to modify existing equipment to get new and improved usability from older or outdated technology, creating an end result that can outshine the pricey higher-end tools. All it takes is some elbow grease, a creative and open mind and the help of Chung's hard-won knowledge on building and modifying telescopes and cameras. With this book, it is possible for readers to improve their craft, making their equipment more user friendly. The tools are at hand, and the advice on how to do it is here. Readers will discover a comprehensive presentation of astronomical projects that any amateur on any budget can replicate – projects that utilize lead...

  13. The Exploration, Discovery, Recovery, and Preservation of Endangered Electronic Scientific Records, the Lunar Orbiter Image Recovery Project

    Science.gov (United States)

    Wingo, D. R.; Harper, M.

    2017-12-01

    In 1966 and 1967 NASA sent five photo reconnaissance satellites to the Moon to scout out sites for the first Apollo landings. This was the first mission in human history to extensively map the Moon to one meter resolution. The Lunar Orbiter spacecraft obtained photographs via 70 millimeter film in high resolution (one meter), and medium resolution (7-8) meter. Each mission took approximately 200 medium and high resolution photographs. These were processed in an on board film laboratory and then scanned via a 6.5 micron light beam.. These images were then transmitted to the Earth as analog waveforms double modulated as a vestigial sideband (VSB) and Frequency Modulation With Feedback (FMFB). The spacecraft transmissions were received at NASA's Deep Space Network at Goldstone (DSS-12), Madrid (DSS-61) and Woomera (DSS-41). The signals received were shifted to a 10 MHz intermediate frequency spectrum which was then written to 2"analog instrumentation tape drives (Ampex-FR-900's). In parallel the signals were demodulated and displayed on a kinescope, which then was photographed using a 35mm camera, and the 35mm film was then rephotographed, processed, and printed for initial analysis by the landing site selection team. The magnetic tape based analog sigals preserved the higher dynamic range of the spacecraft 70mm film, and this was then digitized utilizing digitizer and fed to a Univac 1170 computer for analysis of rock height, slope angles, and geologic context. After the Apollo missions these tapes were largely forgotten. In 2007, retired NASA archivist Nancy Evans, who had saved the last surviving Ampex FR-900's donated the drives to the Lunar Orbiter Image Recovery Project. The project obtained the 1474 hours of original tapes from NASA JPL, and at NASA Ames refurbished the drives. Additionally, the demodulator system was recreated from archived documentation using modern techniques. The project digitized the 1474 tapes, processed the 20 terabyes of raw data. The

  14. Project of the planetary terrain analogs research for technology development and education in geodesy and image processing.

    Science.gov (United States)

    Semenov, Mikhail; Gavrushin, Nikolay; Bataev, Mikhail; Kruzhkov, Maxim; Oberst, Juergen

    2013-04-01

    The MIIGAiK Extraterrestrial Laboratory (MExLab) is currently finalizing the development the robotic mobile science platform MExRover, designed for simulating rover activities on the surface of earth-type planets and satellites. In the project, we develop a hardware and software platform for full rover operation and telemetry processing from onboard instruments, as a means of training undergraduate and postgraduate students and young scientists working in the field of planetary exploration. 1. Introduction The main aim of the project is to provide the research base for image processing development and geodesy survey. Other focus is the development of research programs with participation of students and young scientists of the University, for digital terrain model creation for macro- and microrelief surveying. MExRover would be a bridge from the old soviet Lunokhod experience to the new research base for the future rover technology development support. 2. Rover design The design of the rover and its instrument suite allows acquiring images and navigation data satisfying the requirements for photogrammetric processing. The high-quality color panoramas as well as DTMs (Digital Terrain Models) will be produced aboard and could be used for the real-time track correction and environment analysis. A local operator may control the rover remotely from a distance up to 3 km and continuously monitor all systems. The MExRover has a modular design, which provides maximum flexibility for accomplishing different tasks with different sets of additional equipment weighing up to 15 kg. The framework can be easily disassembled and fit into 3 transport boxes, which allows transporting them on foot, by car, train or plane as a the ordinary luggage. The imaging system included in the present design comprises low resolution video cameras, high resolution stereo camera, microphone and IR camera. More instruments are planned to be installed later as auxiliary equipment, such as

  15. Multiple source associated particle imaging for simultaneous capture of multiple projections

    Science.gov (United States)

    Bingham, Philip R; Hausladen, Paul A; McConchi, Seth M; Mihalczo, John T; Mullens, James A

    2013-11-19

    Disclosed herein are representative embodiments of methods, apparatus, and systems for performing neutron radiography. For example, in one exemplary method, an object is interrogated with a plurality of neutrons. The plurality of neutrons includes a first portion of neutrons generated from a first neutron source and a second portion of neutrons generated from a second neutron source. Further, at least some of the first portion and the second portion are generated during a same time period. In the exemplary method, one or more neutrons from the first portion and one or more neutrons from the second portion are detected, and an image of the object is generated based at least in part on the detected neutrons from the first portion and the detected neutrons from the second portion.

  16. Image quality improvement in a hard X-ray projection microscope using total reflection mirror optics.

    Science.gov (United States)

    Mimura, Hidekazu; Yamauchi, Kazuto; Yamamura, Kazuya; Kubota, Akihisa; Matsuyama, Satoshi; Sano, Yasuhisa; Ueno, Kazumasa; Endo, Katsuyoshi; Nishino, Yoshinori; Tamasaku, Kenji; Yabashi, Makina; Ishikawa, Tetsuya; Mori, Yuzo

    2004-07-01

    A new figure correction method has been applied in order to fabricate an elliptical mirror to realize a one-dimensionally diverging X-ray beam having high image quality. Mutual relations between figure errors and intensity uniformities of diverging X-ray beams have also been investigated using a wave-optical simulator and indicate that figure errors in relatively short spatial wavelength ranges lead to high-contrast interference fringes. By using a microstitching interferometer and elastic emission machining, figure correction of an elliptical mirror with a lateral resolution close to 0.1 mm was carried out. A one-dimensional diverging X-ray obtained using the fabricated mirror was observed at SPring-8 and evaluated to have a sufficiently flat intensity distribution.

  17. Three-dimensional sparse electromagnetic imaging accelerated by projected steepest descent

    KAUST Repository

    Desmal, Abdulla

    2016-11-02

    An efficient and accurate scheme for solving the nonlinear electromagnetic inverse scattering problem on three-dimensional sparse investigation domains is proposed. The minimization problem is constructed in such a way that the data misfit between measurements and scattered fields (which are expressed as a nonlinear function of the contrast) is constrained by the contrast\\'s first norm. The resulting minimization problem is solved using nonlinear Landweber iterations accelerated using a steepest descent algorithm. A projection operator is applied at every iteration to enforce the sparsity constraint by thresholding the result of that iteration. Steepest descent algorithm ensures accelerated and convergent solution by utilizing larger iteration steps selected based on a necessary B-condition.

  18. Characterization of new FPS (Focus Projection and Scale) vidicons for scientific imaging applications

    Science.gov (United States)

    Yates, G. J.; Jaramillo, S. A.; Holmes, V. H.; Black, J. P.

    1988-06-01

    Several new photoconductors now commercially available as targets in Type 7803 FPS (Focus Projection and Scan) electrostatically focussed vidicons have been characterized for use as radiometric sensors in transient illumination and single frame applications. These include Saticon (Se + Te + As), Newvicon (ZnSe), Pasecon (CdSe), and Plumbicon (PbO). Samples from several domestic and foreign manufacturers have been evaluated for photoconductive response time and responsivity at selected narrow wavelength bands, including 410 nm, 560 nm, and 822 nm. These data are compared with performance data from older target materials including antimony trisulfide (Sb2S3) and silicon. Dynamic range and resolution trade-offs as functions of read-beam aperture diameter and raster size are also presented. The point spread functions for standard 1-mil vidicons and for increased apertures of 1.5, 2.0, 3.0, and 4.0-mil are also discussed.

  19. URBAN TREE CROWN PROJECTION AREA MAPPING WITH OBJECT BASED IMAGE ANALYSIS FOR URBAN ECOSYSTEM SERVICE INDICATOR DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    TAKÁCS ÁGNES

    2014-03-01

    Full Text Available The continuous expansion of built-up areas in the urban environment at the expense of green spaces brings up numerous environmental problems, for which accurate and efficient solutions should be found. The assessment of ecosystem services developed within the field of landscape ecology is playing an ever more important role in environmental sciences and thus may offer suitable answers. Such assessments can be carried out by developing indicators. Accordingly, in the case of urban trees, an accurate quantitative characterization of their services (such as e.g. carbon sequestration, pollutant removal and microclimate regulation is also needed. The aim of this study is to establish a generally applicable method based on indicator development, using widely available data. In the case of urban green spaces there are several services for which the development of proper indicators and evaluation methods requires a delineation of tree crowns, or at least the crown projection area. Accordingly, in our work, we map the crown projection area of a large and popular urban park of Szeged, Széchenyi square, using object-based image analysis on UltraCamD digital orthophotos. Following a multiresolution segmentation the classification of the resulting objects was carried out, using the eCognition image analysis software. Besides fulfilling the policy objectives related to the evaluation of urban ecosystem services, the produced crown base can also be used in several other types of urban ecological and urban climatological studies (e.g. urban climate modelling, human-comfort assessment. In this paper the first results are presented.

  20. Electric field conjugation for ground-based high-contrast imaging: robustness study and tests with the Project 1640 coronagraph

    Science.gov (United States)

    Matthews, Christopher T.; Crepp, Justin R.; Vasisht, Gautam; Cady, Eric

    2017-10-01

    The electric field conjugation (EFC) algorithm has shown promise for removing scattered starlight from high-contrast imaging measurements, both in numerical simulations and laboratory experiments. To prepare for the deployment of EFC using ground-based telescopes, we investigate the response of EFC to unaccounted for deviations from an ideal optical model. We explore the linear nature of the algorithm by assessing its response to a range of inaccuracies in the optical model generally present in real systems. We find that the algorithm is particularly sensitive to unresponsive deformable mirror (DM) actuators, misalignment of the Lyot stop, and misalignment of the focal plane mask. Vibrations and DM registration appear to be less of a concern compared to values expected at the telescope. We quantify how accurately one must model these core coronagraph components to ensure successful EFC corrections. We conclude that while the condition of the DM can limit contrast, EFC may still be used to improve the sensitivity of high-contrast imaging observations. Our results have informed the development of a full EFC implementation using the Project 1640 coronagraph at Palomar observatory. While focused on a specific instrument, our results are applicable to the many coronagraphs that may be interested in employing EFC.

  1. Successive Projections Algorithm-Multivariable Linear Regression Classifier for the Detection of Contaminants on Chicken Carcasses in Hyperspectral Images

    Science.gov (United States)

    Wu, W.; Chen, G. Y.; Kang, R.; Xia, J. C.; Huang, Y. P.; Chen, K. J.

    2017-07-01

    During slaughtering and further processing, chicken carcasses are inevitably contaminated by microbial pathogen contaminants. Due to food safety concerns, many countries implement a zero-tolerance policy that forbids the placement of visibly contaminated carcasses in ice-water chiller tanks during processing. Manual detection of contaminants is labor consuming and imprecise. Here, a successive projections algorithm (SPA)-multivariable linear regression (MLR) classifier based on an optimal performance threshold was developed for automatic detection of contaminants on chicken carcasses. Hyperspectral images were obtained using a hyperspectral imaging system. A regression model of the classifier was established by MLR based on twelve characteristic wavelengths (505, 537, 561, 562, 564, 575, 604, 627, 656, 665, 670, and 689 nm) selected by SPA , and the optimal threshold T = 1 was obtained from the receiver operating characteristic (ROC) analysis. The SPA-MLR classifier provided the best detection results when compared with the SPA-partial least squares (PLS) regression classifier and the SPA-least squares supported vector machine (LS-SVM) classifier. The true positive rate (TPR) of 100% and the false positive rate (FPR) of 0.392% indicate that the SPA-MLR classifier can utilize spatial and spectral information to effectively detect contaminants on chicken carcasses.

  2. A PET reconstruction formulation that enforces non-negativity in projection space for bias reduction in Y-90 imaging

    Science.gov (United States)

    Lim, Hongki; Dewaraja, Yuni K.; Fessler, Jeffrey A.

    2018-02-01

    Most existing PET image reconstruction methods impose a nonnegativity constraint in the image domain that is natural physically, but can lead to biased reconstructions. This bias is particularly problematic for Y-90 PET because of the low probability positron production and high random coincidence fraction. This paper investigates a new PET reconstruction formulation that enforces nonnegativity of the projections instead of the voxel values. This formulation allows some negative voxel values, thereby potentially reducing bias. Unlike the previously reported NEG-ML approach that modifies the Poisson log-likelihood to allow negative values, the new formulation retains the classical Poisson statistical model. To relax the non-negativity constraint embedded in the standard methods for PET reconstruction, we used an alternating direction method of multipliers (ADMM). Because choice of ADMM parameters can greatly influence convergence rate, we applied an automatic parameter selection method to improve the convergence speed. We investigated the methods using lung to liver slices of XCAT phantom. We simulated low true coincidence count-rates with high random fractions corresponding to the typical values from patient imaging in Y-90 microsphere radioembolization. We compared our new methods with standard reconstruction algorithms and NEG-ML and a regularized version thereof. Both our new method and NEG-ML allow more accurate quantification in all volumes of interest while yielding lower noise than the standard method. The performance of NEG-ML can degrade when its user-defined parameter is tuned poorly, while the proposed algorithm is robust to any count level without requiring parameter tuning.

  3. Sleep paralysis and "the bedroom intruder": the role of the right superior parietal, phantom pain and body image projection.

    Science.gov (United States)

    Jalal, Baland; Ramachandran, Vilayanur S

    2014-12-01

    Sleep paralysis (SP) is a common condition occurring either at sleep onset or sleep offset. During SP the sleeper experiences gross motor paralysis while the sensory system is clear. Hypnogogic and hypnopompic hallucinations are common during SP and may involve seeing, hearing, and sensing the presence of menacing intruders in one's bedroom. This "intruder" is often perceived as a shadowy humanoid figure. Supernatural accounts of this hallucinated intruder are common across cultures. In this paper, we postulate that a functional disturbance of the right parietal cortex explains the shadowy nocturnal bedroom intruder hallucination during SP. This hallucination may arise due to a disturbance in the multisensory processing of body and self at the temporoparietal junction. We specifically propose that this perceived intruder is the result of a hallucinated projection of the genetically "hard-wired" body image (homunculus), in the right parietal region; namely, the same circuits that dictate aesthetic and sexual preference of body morphology. One way to test this hypothesis would be to study clinical populations who may have genetically acquired "irregularities" in their internal hard-wired body image in the right superior parietal lobule (SPL); for example, individuals with apotemnophilia or anorexia nervosa. If such individuals experience SP (e.g., induced in a sleep lab), and they hallucinate this shadowy figure, one would predict that they would see humanoid shadows and shapes with body irregularities, mirroring their own internal body image morphology. If correct, our hypothesis will offer a neurological explanation for this nocturnal bedroom intruder that has been a source of controversy, and striking and implausible cultural interpretations throughout history. Indeed, if our proposed hypothesis is tested and corroborated, dissemination of such findings would provide great relief to SP experiencers worldwide and could potentially be used in a therapeutic context

  4. Critical Elements for Successful Implementation and Adoption of Authentic Scientific Research Programs: Lessons Learned from NASA's Mars Student Imaging Project

    Science.gov (United States)

    Klug Boonstra, S.; Swann, J.; Boonstra, D.; Manfredi, L.; Christensen, P. R.

    2016-12-01

    Recent research identifies the most effective learning as active, engaged learning in which students interact with phenomena, other students, and the teacher/leader to derive meaning and construct understanding of their surroundings. "Similarly, an engaging and effective science education goes well beyond the low-level factual recall that is emphasized in many science classes. It must develop the skills that students need to solve complex problems, work in teams, make and recognize evidence-based arguments, and interpret and communicate complex information" (emphasis added). Authentic science research projects provide active, engaged learning in which students interact with authentic science data in an authentic problem-solving context to derive meaning and construct understanding of the world. In formal (and many informal) settings, the teacher/leader is effectively the gatekeeper who determines the learning experiences in which the students will participate. From our experience of nearly a decade and a half of authentic science programming for 5thgrade through early college students working with NASA Mars data, supporting and enabling the teacher is perhaps the most critical and foundational element for designing a successful authentic research experience. Yet, a major barrier to this type of learning are teacher/leaders who are too often not equipped or who lack confidence to succeed in facilitating authentic research projects. The Mars Student Imaging Project has implemented an iterative process of design, testing, and redesign that has identified and implemented critical teacher/leader-enabling elements that have led to increasingly successful adoptions within formal and informal educational settings - allowing more students to gain the benefits of immersive research experience.

  5. Cone beam CT imaging with limited angle of projections and prior knowledge for volumetric verification of non-coplanar beam radiation therapy: a proof of concept study

    International Nuclear Information System (INIS)

    Meng, Bowen; Xing, Lei; Han, Bin; Koong, Albert; Chang, Daniel; Li, Ruijiang; Cheng, Jason

    2013-01-01

    Non-coplanar beams are important for treatment of both cranial and noncranial tumors. Treatment verification of such beams with couch rotation/kicks, however, is challenging, particularly for the application of cone beam CT (CBCT). In this situation, only limited and unconventional imaging angles are feasible to avoid collision between the gantry, couch, patient, and on-board imaging system. The purpose of this work is to develop a CBCT verification strategy for patients undergoing non-coplanar radiation therapy. We propose an image reconstruction scheme that integrates a prior image constrained compressed sensing (PICCS) technique with image registration. Planning CT or CBCT acquired at the neutral position is rotated and translated according to the nominal couch rotation/translation to serve as the initial prior image. Here, the nominal couch movement is chosen to have a rotational error of 5° and translational error of 8 mm from the ground truth in one or more axes or directions. The proposed reconstruction scheme alternates between two major steps. First, an image is reconstructed using the PICCS technique implemented with total-variation minimization and simultaneous algebraic reconstruction. Second, the rotational/translational setup errors are corrected and the prior image is updated by applying rigid image registration between the reconstructed image and the previous prior image. The PICCS algorithm and rigid image registration are alternated iteratively until the registration results fall below a predetermined threshold. The proposed reconstruction algorithm is evaluated with an anthropomorphic digital phantom and physical head phantom. The proposed algorithm provides useful volumetric images for patient setup using projections with an angular range as small as 60°. It reduced the translational setup errors from 8 mm to generally <1 mm and the rotational setup errors from 5° to <1°. Compared with the PICCS algorithm alone, the integration of rigid

  6. Classification of projection images of proteins with structural polymorphism by manifold: A simulation study for x-ray free-electron laser diffraction imaging

    Science.gov (United States)

    Yoshidome, Takashi; Oroguchi, Tomotaka; Nakasako, Masayoshi; Ikeguchi, Mitsunori

    2015-09-01

    Coherent x-ray diffraction imaging (CXDI) enables us to visualize noncrystalline sample particles with micrometer to submicrometer dimensions. Using x-ray free-electron laser (XFEL) sources, two-dimensional diffraction patterns are collected from fresh samples supplied to the irradiation area in the "diffraction-before-destruction" scheme. A recent significant increase in the intensity of the XFEL pulse is promising and will allow us to visualize the three-dimensional structures of proteins using XFEL-CXDI in the future. For the protocol proposed for molecular structure determination using future XFEL-CXDI [T. Oroguchi and M. Nakasako, Phys. Rev. E 87, 022712 (2013), 10.1103/PhysRevE.87.022712], we require an algorithm that can classify the data in accordance with the structural polymorphism of proteins arising from their conformational dynamics. However, most of the algorithms proposed primarily require the numbers of conformational classes, and then the results are biased by the numbers. To improve this point, here we examine whether a method based on the manifold concept can classify simulated XFEL-CXDI data with respect to the structural polymorphism of a protein that predominantly adopts two states. After random sampling of the conformations of the two states and in-between states from the trajectories of molecular dynamics simulations, a diffraction pattern is calculated from each conformation. Classification was performed by using our custom-made program suite named enma, in which the diffusion map (DM) method developed based on the manifold concept was implemented. We successfully classify most of the projection electron density maps phase retrieved from diffraction patterns into each of the two states and in-between conformations without the knowledge of the number of conformational classes. We also examined the classification of the projection electron density maps of each of the three states with respect to the Euler angle. The present results suggest

  7. Effects of defect pixel correction algorithms for x-ray detectors on image quality in planar projection and volumetric CT data sets

    International Nuclear Information System (INIS)

    Kuttig, Jan; Steiding, Christian; Hupfer, Martin; Karolczak, Marek; Kolditz, Daniel

    2015-01-01

    In this study we compared various defect pixel correction methods for reducing artifact appearance within projection images used for computed tomography (CT) reconstructions.Defect pixel correction algorithms were examined with respect to their artifact behaviour within planar projection images as well as in volumetric CT reconstructions. We investigated four algorithms: nearest neighbour, linear and adaptive linear interpolation, and a frequency-selective spectral-domain approach.To characterise the quality of each algorithm in planar image data, we inserted line defects of varying widths and orientations into images. The structure preservation of each algorithm was analysed by corrupting and correcting the image of a slit phantom pattern and by evaluating its line spread function (LSF). The noise preservation was assessed by interpolating corrupted flat images and estimating the noise power spectrum (NPS) of the interpolated region.For the volumetric investigations, we examined the structure and noise preservation within a structured aluminium foam, a mid-contrast cone-beam phantom and a homogeneous Polyurethane (PUR) cylinder.The frequency-selective algorithm showed the best structure and noise preservation for planar data of the correction methods tested. For volumetric data it still showed the best noise preservation, whereas the structure preservation was outperformed by the linear interpolation.The frequency-selective spectral-domain approach in the correction of line defects is recommended for planar image data, but its abilities within high-contrast volumes are restricted. In that case, the application of a simple linear interpolation might be the better choice to correct line defects within projection images used for CT. (paper)

  8. a Modified Projective Transformation Scheme for Mosaicking Multi-Camera Imaging System Equipped on a Large Payload Fixed-Wing Uas

    Science.gov (United States)

    Jhan, J. P.; Li, Y. T.; Rau, J. Y.

    2015-03-01

    In recent years, Unmanned Aerial System (UAS) has been applied to collect aerial images for mapping, disaster investigation, vegetation monitoring and etc. It is a higher mobility and lower risk platform for human operation, but the low payload and short operation time reduce the image collection efficiency. In this study, one nadir and four oblique consumer grade DSLR cameras composed multiple camera system is equipped on a large payload UAS, which is designed to collect large ground coverage images in an effective way. The field of view (FOV) is increased to 127 degree, which is thus suitable to collect disaster images in mountainous area. The synthetic acquired five images are registered and mosaicked as larger format virtual image for reducing the number of images, post processing time, and for easier stereo plotting. Instead of traditional image matching and applying bundle adjustment method to estimate transformation parameters, the IOPs and ROPs of multiple cameras are calibrated and derived the coefficients of modified projective transformation (MPT) model for image mosaicking. However, there are some uncertainty of indoor calibrated IOPs and ROPs since the different environment conditions as well as the vibration of UAS, which will cause misregistration effect of initial MPT results. Remaining residuals are analysed through tie points matching on overlapping area of initial MPT results, in which displacement and scale difference are introduced and corrected to modify the ROPs and IOPs for finer registration results. In this experiment, the internal accuracy of mosaic image is better than 0.5 pixels after correcting the systematic errors. Comparison between separate cameras and mosaic images through rigorous aerial triangulation are conducted, in which the RMSE of 5 control and 9 check points is less than 5 cm and 10 cm in planimetric and vertical directions, respectively, for all cases. It proves that the designed imaging system and the proposed scheme

  9. Techniques for virtual lung nodule insertion: volumetric and morphometric comparison of projection-based and image-based methods for quantitative CT

    Science.gov (United States)

    Robins, Marthony; Solomon, Justin; Sahbaee, Pooyan; Sedlmair, Martin; Choudhury, Kingshuk Roy; Pezeshk, Aria; Sahiner, Berkman; Samei, Ehsan

    2017-09-01

    Virtual nodule insertion paves the way towards the development of standardized databases of hybrid CT images with known lesions. The purpose of this study was to assess three methods (an established and two newly developed techniques) for inserting virtual lung nodules into CT images. Assessment was done by comparing virtual nodule volume and shape to the CT-derived volume and shape of synthetic nodules. 24 synthetic nodules (three sizes, four morphologies, two repeats) were physically inserted into the lung cavity of an anthropomorphic chest phantom (KYOTO KAGAKU). The phantom was imaged with and without nodules on a commercial CT scanner (SOMATOM Definition Flash, Siemens) using a standard thoracic CT protocol at two dose levels (1.4 and 22 mGy CTDIvol). Raw projection data were saved and reconstructed with filtered back-projection and sinogram affirmed iterative reconstruction (SAFIRE, strength 5) at 0.6 mm slice thickness. Corresponding 3D idealized, virtual nodule models were co-registered with the CT images to determine each nodule’s location and orientation. Virtual nodules were voxelized, partial volume corrected, and inserted into nodule-free CT data (accounting for system imaging physics) using two methods: projection-based Technique A, and image-based Technique B. Also a third Technique C based on cropping a region of interest from the acquired image of the real nodule and blending it into the nodule-free image was tested. Nodule volumes were measured using a commercial segmentation tool (iNtuition, TeraRecon, Inc.) and deformation was assessed using the Hausdorff distance. Nodule volumes and deformations were compared between the idealized, CT-derived and virtual nodules using a linear mixed effects regression model which utilized the mean, standard deviation, and coefficient of variation (Mea{{n}RHD} , ST{{D}RHD} and C{{V}RHD}{) }~ of the regional Hausdorff distance. Overall, there was a close concordance between the volumes of the CT-derived and

  10. Techniques for virtual lung nodule insertion: volumetric and morphometric comparison of projection-based and image-based methods for quantitative CT.

    Science.gov (United States)

    Robins, Marthony; Solomon, Justin; Sahbaee, Pooyan; Sedlmair, Martin; Roy Choudhury, Kingshuk; Pezeshk, Aria; Sahiner, Berkman; Samei, Ehsan

    2017-08-22

    Virtual nodule insertion paves the way towards the development of standardized databases of hybrid CT images with known lesions. The purpose of this study was to assess three methods (an established and two newly developed techniques) for inserting virtual lung nodules into CT images. Assessment was done by comparing virtual nodule volume and shape to the CT-derived volume and shape of synthetic nodules. 24 synthetic nodules (three sizes, four morphologies, two repeats) were physically inserted into the lung cavity of an anthropomorphic chest phantom (KYOTO KAGAKU). The phantom was imaged with and without nodules on a commercial CT scanner (SOMATOM Definition Flash, Siemens) using a standard thoracic CT protocol at two dose levels (1.4 and 22 mGy CTDI vol ). Raw projection data were saved and reconstructed with filtered back-projection and sinogram affirmed iterative reconstruction (SAFIRE, strength 5) at 0.6 mm slice thickness. Corresponding 3D idealized, virtual nodule models were co-registered with the CT images to determine each nodule's location and orientation. Virtual nodules were voxelized, partial volume corrected, and inserted into nodule-free CT data (accounting for system imaging physics) using two methods: projection-based Technique A, and image-based Technique B. Also a third Technique C based on cropping a region of interest from the acquired image of the real nodule and blending it into the nodule-free image was tested. Nodule volumes were measured using a commercial segmentation tool (iNtuition, TeraRecon, Inc.) and deformation was assessed using the Hausdorff distance. Nodule volumes and deformations were compared between the idealized, CT-derived and virtual nodules using a linear mixed effects regression model which utilized the mean, standard deviation, and coefficient of variation ([Formula: see text], [Formula: see text] and [Formula: see text] of the regional Hausdorff distance. Overall, there was a close concordance between the volumes of

  11. Techniques for virtual lung nodule insertion: volumetric and morphometric comparison of projection-based and image-based methods for quantitative CT

    Science.gov (United States)

    Robins, Marthony; Solomon, Justin; Sahbaee, Pooyan; Sedlmair, Martin; Choudhury, Kingshuk Roy; Pezeshk, Aria; Sahiner, Berkman; Samei, Ehsan

    2017-01-01

    Virtual nodule insertion paves the way towards the development of standardized databases of hybrid CT images with known lesions. The purpose of this study was to assess three methods (an established and two newly developed techniques) for inserting virtual lung nodules into CT images. Assessment was done by comparing virtual nodule volume and shape to the CT-derived volume and shape of synthetic nodules. 24 synthetic nodules (three sizes, four morphologies, two repeats) were physically inserted into the lung cavity of an anthropomorphic chest phantom (KYOTO KAGAKU). The phantom was imaged with and without nodules on a commercial CT scanner (SOMATOM Definition Flash, Siemens) using a standard thoracic CT protocol at two dose levels (1.4 and 22 mGy CTDIvol). Raw projection data were saved and reconstructed with filtered back-projection and sinogram affirmed iterative reconstruction (SAFIRE, strength 5) at 0.6 mm slice thickness. Corresponding 3D idealized, virtual nodule models were co-registered with the CT images to determine each nodule’s location and orientation. Virtual nodules were voxelized, partial volume corrected, and inserted into nodule-free CT data (accounting for system imaging physics) using two methods: projection-based Technique A, and image-based Technique B. Also a third Technique C based on cropping a region of interest from the acquired image of the real nodule and blending it into the nodule-free image was tested. Nodule volumes were measured using a commercial segmentation tool (iNtuition, TeraRecon, Inc.) and deformation was assessed using the Hausdorff distance. Nodule volumes and deformations were compared between the idealized, CT-derived and virtual nodules using a linear mixed effects regression model which utilized the mean, standard deviation, and coefficient of variation (MeanRHD, and STDRHD CVRHD) of the regional Hausdorff distance. Overall, there was a close concordance between the volumes of the CT-derived and virtual nodules

  12. Projection-type integral imaging system using a three-dimensional screen composed of a lens array and a retroreflector film.

    Science.gov (United States)

    Kim, Young Min; Song, Byoungsub; Min, Sung-Wook

    2017-05-01

    We propose an improved projection-type integral imaging system using a three-dimensional (3D) screen consisting of a lens array and a retroreflector film in this paper. The projection-type integral imaging system suffers from the disadvantage of low-visibility images because of the inherently small exit pupil size of the projector. In order to resolve this problem, we adopt a 3D screen to avoid the demerits of a diffuser screen, such as off-screen image blur and loss of parallax. To determine the appropriate configuration of the 3D screen in the system, a simulation based on a ray transfer matrix analysis method was performed. The results show that the 3D screen should be located near the central depth plane of the integral imaging system, which leads to the conclusion that only the real mode is available for the proposed system. Experiments to verify this configuration and the feasibility of the proposed system were conducted using a system constructed with a real mode integral imaging system including a convex mirror array, which can fundamentally eliminate the pseudoscopic problem.

  13. Exoplanet Direct Imaging Project

    Data.gov (United States)

    National Aeronautics and Space Administration — "We propose to develop high contrast coronagraphic techniques for segmented telescopes, providing an integrated solution for wavefront control and starlight...

  14. Hyperspectral Imager - Tracker Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address the NASA need for innovative optical technique for visualization and tracking of space vehicles during launch and landing operations, Light Prescriptions...

  15. Utilization of multiparametric prostate magnetic resonance imaging in clinical practice and focal therapy: report from a Delphi consensus project.

    Science.gov (United States)

    Scheltema, M J; Tay, K J; Postema, A W; de Bruin, D M; Feller, J; Futterer, J J; George, A K; Gupta, R T; Kahmann, F; Kastner, C; Laguna, M P; Natarajan, S; Rais-Bahrami, S; Rastinehad, A R; de Reijke, T M; Salomon, G; Stone, N; van Velthoven, R; Villani, R; Villers, A; Walz, J; Polascik, T J; de la Rosette, J J M C H

    2017-05-01

    To codify the use of multiparametric magnetic resonance imaging (mpMRI) for the interrogation of prostate neoplasia (PCa) in clinical practice and focal therapy (FT). An international collaborative consensus project was undertaken using the Delphi method among experts in the field of PCa. An online questionnaire was presented in three consecutive rounds and modified each round based on the comments provided by the experts. Subsequently, a face-to-face meeting was held to discuss and finalize the consensus results. mpMRI should be performed in patients with prior negative biopsies if clinical suspicion remains, but not instead of the PSA test, nor as a stand-alone diagnostic tool or mpMRI-targeted biopsies only. It is not recommended to use a 1.5 Tesla MRI scanner without an endorectal or pelvic phased-array coil. mpMRI should be performed following standard biopsy-based PCa diagnosis in both the planning and follow-up of FT. If a lesion is seen, MRI-TRUS fusion biopsies should be performed for FT planning. Systematic biopsies are still required for FT planning in biopsy-naïve patients and for patients with residual PCa after FT. Standard repeat biopsies should be taken during the follow-up of FT. The final decision to perform FT should be based on histopathology. However, these consensus statements may differ for expert centers versus non-expert centers. The mpMRI is an important tool for characterizing and targeting PCa in clinical practice and FT. Standardization of acquisition and reading should be the main priority to guarantee consistent mpMRI quality throughout the urological community.

  16. The German Dunkelfeld project: a pilot study to prevent child sexual abuse and the use of child abusive images.

    Science.gov (United States)

    Beier, Klaus M; Grundmann, Dorit; Kuhle, Laura F; Scherner, Gerold; Konrad, Anna; Amelung, Till

    2015-02-01

    Sexual interest toward prepubescents and pubescents (pedophilia and hebephilia) constitutes a major risk factor for child sexual abuse (CSA) and viewing of child abusive images, i.e., child pornography offenses (CPO). Most child sexual exploitation involving CSA and CPO are undetected and unprosecuted in the "Dunkelfeld" (German: "dark field"). This study assesses a treatment program to enhance behavioral control and reduce associated dynamic risk factors (DRF) in self-motivated pedophiles/hebephiles in the Dunkelfeld. Between 2005 and 2011, 319 undetected help-seeking pedophiles and hebephiles expressed interest in taking part in an anonymous and confidential 1-year-treatment program using broad cognitive behavioral methodology in the Prevention Project Dunkelfeld. Therapy was assessed using nonrandomized waiting list control design (n=53 treated group [TG]; n=22 untreated control group [CG]). Self-reported pre-/posttreatment DRF changes were assessed and compared with CG. Offending behavior characteristics were also assessed via self-reporting. No pre-/postassessment changes occurred in the control group. Emotional deficits and offense-supportive cognitions decreased in the TG; posttherapy sexual self-regulation increased. Treatment-related changes were distributed unequally across offender groups. None of the offending behavior reported for the TG was identified as such by the legal authorities. However, five of 25 CSA offenders and 29 of 32 CPO offenders reported ongoing behaviors under therapy. Therapy for pedophiles/hebephiles in the Dunkelfeld can alter child sexual offending DRF and reduce-related behaviors. Unidentified, unlawful child sexual exploitative behaviors are more prevalent in this population than in officially reported recidivism. Further research into factors predictive of problematic sexual behaviors in the Dunkelfeld is warranted. © 2014 International Society for Sexual Medicine.

  17. A general approach to flaw simulation in castings by superimposing projections of 3D models onto real X-ray images

    International Nuclear Information System (INIS)

    Hahn, D.; Mery, D.

    2003-01-01

    In order to evaluate the sensitivity of defect inspection systems, it is convenient to examine simulated data. This gives the possibility to tune the parameters of the inspection method and to test the performance of the system in critical cases. In this paper, a practical method for the simulation of defects in radioscopic images of aluminium castings is presented. The approach simulates only the flaws and not the whole radioscopic image of the object under test. A 3D mesh is used to model a flaw with complex geometry, which is projected and superimposed onto real radioscopic images of a homogeneous object according to the exponential attenuation law for X- rays. The new grey value of a pixel, where the 3D flaw is projected, depends only on four parameters: (a) the grey value of the original X-ray image without flaw; (b) the linear absorption coefficient of the examined material; (c) the maximal thickness observable in the radioscopic image; and (d) the length of the intersection of the 3D flaw with the modelled X-ray beam, that is projected into the pixel. A simulation of a complex flaw modelled as a 3D mesh can be performed in any position of the castings by using the algorithm described in this paper. This allows the evaluation of the performance of defect inspection systems in cases where the detection is known to be difficult. In this paper, we show experimental results on real X-ray images of aluminium wheels, in which 3D flaws like blowholes, cracks and inclusions are simulated

  18. Undersampled radial MR acquisition and highly constrained back projection (HYPR) reconstruction: potential medical imaging applications in the post-Nyquist era.

    Science.gov (United States)

    Mistretta, Charles A

    2009-03-01

    During the past several years there has been extensive study of alternative MR acquisition strategies such as spiral and radial. Vastly undersampled imaging with projections (VIPR) is a three-dimensional (3D) radial acquisition that provides acceptable images while violating the Nyquist theorem by factors of up to several hundred. For applications like magnetic resonance angiography (MRA), VIPR provides sparse data sets with incoherent artifacts that satisfy the requirements of emerging reconstruction approaches like iterative image norm minimization (compressed sensing) and highly constrained back projection (HYPR). All of these tools can be used in combination with parallel imaging to provide extremely high acceleration factors in MRI. In this review we do not attempt to do justice to the many exciting developments in the general field of constrained reconstruction but focus on preliminary results using VIPR and HYPR for non-Cartesian, Nyquist-violating MRI and the extension of HYPR processing to a broad range of medical imaging applications in which the acquisitions satisfy the Nyquist theorem but lack sufficient signal-to-noise ratio (SNR), leading to the possibility of radiation reduction, increased ultrasound resolution and field-of-view, and improved dynamic display of radiotracers. Copyright (c) 2009 Wiley-Liss, Inc.

  19. MaRIE 1.0: The Matter-Radiation Interactions in Extremes Project, and the Challenge of Dynamic Mesoscale Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, Cris William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Barber, John L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kober, Edward Martin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lookman, Turab [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sandberg, Richard L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Shlachter, Jack S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sheffield, Richard L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-23

    The Matter-Radiation Interactions in Extremes project will build the experimental facility for the time-dependent control of dynamic material performance. An x-ray free electron laser at up to 42-keV fundamental energy and with photon pulses down to sub-nanosecond spacing, MaRIE 1.0 is designed to meet the challenges of time-dependent mesoscale materials science. Those challenges will be outlined, the techniques of coherent diffractive imaging and dynamic polycrystalline diffraction described, and the resulting requirements defined for a coherent x-ray source. The talk concludes with the role of the MaRIE project and science in the future.

  20. Teaching Strategies for Using Projected Images to Develop Conceptual Understanding: Exploring Discussion Practices in Computer Simulation and Static Image-Based Lessons

    Science.gov (United States)

    Price, Norman T.

    2013-01-01

    The availability and sophistication of visual display images, such as simulations, for use in science classrooms has increased exponentially however, it can be difficult for teachers to use these images to encourage and engage active student thinking. There is a need to describe flexible discussion strategies that use visual media to engage active…

  1. Images.

    Science.gov (United States)

    Barr, Catherine, Ed.

    1997-01-01

    The theme of this month's issue is "Images"--from early paintings and statuary to computer-generated design. Resources on the theme include Web sites, CD-ROMs and software, videos, books, and others. A page of reproducible activities is also provided. Features include photojournalism, inspirational Web sites, art history, pop art, and myths. (AEF)

  2. Evaluation of radiological workstations and web-browser-based image distribution clients for a PACS project in hands-on workshops

    International Nuclear Information System (INIS)

    Boehm, Thomas; Handgraetinger, Oliver; Voellmy, Daniel R.; Marincek, Borut; Wildermuth, Simon; Link, Juergen; Ploner, Ricardo

    2004-01-01

    The methodology and outcome of a hands-on workshop for the evaluation of PACS (picture archiving and communication system) software for a multihospital PACS project are described. The following radiological workstations and web-browser-based image distribution software clients were evaluated as part of a multistep evaluation of PACS vendors in March 2001: Impax DS 3000 V 4.1/Impax Web1000 (Agfa-Gevaert, Mortsel, Belgium); PathSpeed V 8.0/PathSpeed Web (GE Medical Systems, Milwaukee, Wis., USA); ID Report/ID Web (Image Devices, Idstein, Germany); EasyVision DX/EasyWeb (Philips Medical Systems, Eindhoven, Netherlands); and MagicView 1000 VB33a/MagicWeb (Siemens Medical Systems, Erlangen, Germany). A set of anonymized DICOM test data was provided to enable direct image comparison. Radiologists (n=44) evaluated the radiological workstations and nonradiologists (n=53) evaluated the image distribution software clients using different questionnaires. One vendor was not able to import the provided DICOM data set. Another vendor had problems in displaying imported cross-sectional studies in the correct stack order. Three vendors (Agfa-Gevaert, GE, Philips) presented server-client solutions with web access. Two (Siemens, Image Devices) presented stand-alone solutions. The highest scores in the class of radiological workstations were achieved by ID Report from Image Devices (p<0.005). In the class of image distribution clients, the differences were statistically not significant. Questionnaire-based evaluation was shown to be useful for guaranteeing systematic assessment. The workshop was a great success in raising interest in the PACS project in a large group of future clinical users. The methodology used in the present study may be useful for other hospitals evaluating PACS. (orig.)

  3. Adaptive iterative dose reduction algorithm in CT: Effect on image quality compared with filtered back projection in body phantoms of different sizes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Milim; Lee, Jeong Min; Son, Hyo Shin; Han, Joon Koo; Choi, Byung Ihn [College of Medicine, Seoul National University, Seoul (Korea, Republic of); Yoon, Jeong Hee; Choi, Jin Woo [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-04-15

    To evaluate the impact of the adaptive iterative dose reduction (AIDR) three-dimensional (3D) algorithm in CT on noise reduction and the image quality compared to the filtered back projection (FBP) algorithm and to compare the effectiveness of AIDR 3D on noise reduction according to the body habitus using phantoms with different sizes. Three different-sized phantoms with diameters of 24 cm, 30 cm, and 40 cm were built up using the American College of Radiology CT accreditation phantom and layers of pork belly fat. Each phantom was scanned eight times using different mAs. Images were reconstructed using the FBP and three different strengths of the AIDR 3D. The image noise, the contrast-to-noise ratio (CNR) and the signal-to-noise ratio (SNR) of the phantom were assessed. Two radiologists assessed the image quality of the 4 image sets in consensus. The effectiveness of AIDR 3D on noise reduction compared with FBP were also compared according to the phantom sizes. Adaptive iterative dose reduction 3D significantly reduced the image noise compared with FBP and enhanced the SNR and CNR (p < 0.05) with improved image quality (p < 0.05). When a stronger reconstruction algorithm was used, greater increase of SNR and CNR as well as noise reduction was achieved (p < 0.05). The noise reduction effect of AIDR 3D was significantly greater in the 40-cm phantom than in the 24-cm or 30-cm phantoms (p < 0.05). The AIDR 3D algorithm is effective to reduce the image noise as well as to improve the image-quality parameters compared by FBP algorithm, and its effectiveness may increase as the phantom size increases.

  4. An optimization algorithm for 3D real-time lung tumor tracking during arc therapy using kV projection images.

    Science.gov (United States)

    Zhuang, Ling; Liang, Jian; Yan, Di; Zhang, Tiezhi; Marina, Ovidiu; Ionascu, Dan

    2013-10-01

    To develop a real-time markerless 3D tumor tracking using kilovoltage (kV) cone-beam CT (CBCT) projection images during volumetric modulated arc therapy (VMAT) treatment of lung tumors. The authors have developed a method to identify the position of lung tumors during VMAT treatment, where the current mean 3D position is detected and subsequently the real time 3D position is obtained. The mean position is evaluated by iteratively minimizing an observation error function between the tumor coordinate detected in the imaging plane and the coordinate of the corresponding projection of the estimated mean position. The 3D trajectory is reconstructed using the same optimization formalism, where an observation error function is minimized for tumor positions confined within a predefined amplitude bin as determined from the superior-inferior tumor motion. Dynamic phantom experiments were performed and image data acquired during patient treatment were analyzed to characterize the reconstruction ability of the proposed method. The proposed algorithm needs to acquire kV projection data until a certain gantry angle is passed through, termed the black-out angle, before accurate estimation mean 3D tumor position is possible. The black-out angle for the mean position method is approximately 20°, while for the 3D trajectory reconstruction an additional ≈ 15° is required. The mean 3D position and 3D trajectory reconstruction are accurate within ± 0.5 mm. The authors present a real-time tracking framework to locate lung tumors during VMAT treatment using an optimization algorithm applied to CBCT kV projection images taken concomitantly with the treatment delivery. The authors' technique does not introduce significant additional dose and can be used for real-time treatment monitoring.

  5. Accuracy of Dual-Energy Virtual Monochromatic CT Numbers: Comparison between the Single-Source Projection-Based and Dual-Source Image-Based Methods.

    Science.gov (United States)

    Ueguchi, Takashi; Ogihara, Ryota; Yamada, Sachiko

    2018-03-21

    To investigate the accuracy of dual-energy virtual monochromatic computed tomography (CT) numbers obtained by two typical hardware and software implementations: the single-source projection-based method and the dual-source image-based method. A phantom with different tissue equivalent inserts was scanned with both single-source and dual-source scanners. A fast kVp-switching feature was used on the single-source scanner, whereas a tin filter was used on the dual-source scanner. Virtual monochromatic CT images of the phantom at energy levels of 60, 100, and 140 keV were obtained by both projection-based (on the single-source scanner) and image-based (on the dual-source scanner) methods. The accuracy of virtual monochromatic CT numbers for all inserts was assessed by comparing measured values to their corresponding true values. Linear regression analysis was performed to evaluate the dependency of measured CT numbers on tissue attenuation, method, and their interaction. Root mean square values of systematic error over all inserts at 60, 100, and 140 keV were approximately 53, 21, and 29 Hounsfield unit (HU) with the single-source projection-based method, and 46, 7, and 6 HU with the dual-source image-based method, respectively. Linear regression analysis revealed that the interaction between the attenuation and the method had a statistically significant effect on the measured CT numbers at 100 and 140 keV. There were attenuation-, method-, and energy level-dependent systematic errors in the measured virtual monochromatic CT numbers. CT number reproducibility was comparable between the two scanners, and CT numbers had better accuracy with the dual-source image-based method at 100 and 140 keV. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  6. The Advanced Rapid Imaging and Analysis (ARIA) Project: Status of SAR products for Earthquakes, Floods, Volcanoes and Groundwater-related Subsidence

    Science.gov (United States)

    Owen, S. E.; Yun, S. H.; Hua, H.; Agram, P. S.; Liu, Z.; Sacco, G. F.; Manipon, G.; Linick, J. P.; Fielding, E. J.; Lundgren, P.; Farr, T. G.; Webb, F.; Rosen, P. A.; Simons, M.

    2017-12-01

    The Advanced Rapid Imaging and Analysis (ARIA) project for Natural Hazards is focused on rapidly generating high-level geodetic imaging products and placing them in the hands of the solid earth science and local, national, and international natural hazard communities by providing science product generation, exploration, and delivery capabilities at an operational level. Space-based geodetic measurement techniques including Interferometric Synthetic Aperture Radar (InSAR), differential Global Positioning System, and SAR-based change detection have become critical additions to our toolset for understanding and mapping the damage and deformation caused by earthquakes, volcanic eruptions, floods, landslides, and groundwater extraction. Up until recently, processing of these data sets has been handcrafted for each study or event and has not generated products rapidly and reliably enough for response to natural disasters or for timely analysis of large data sets. The ARIA project, a joint venture co-sponsored by the California Institute of Technology and by NASA through the Jet Propulsion Laboratory, has been capturing the knowledge applied to these responses and building it into an automated infrastructure to generate imaging products in near real-time that can improve situational awareness for disaster response. In addition to supporting the growing science and hazard response communities, the ARIA project has developed the capabilities to provide automated imaging and analysis capabilities necessary to keep up with the influx of raw SAR data from geodetic imaging missions such as ESA's Sentinel-1A/B, now operating with repeat intervals as short as 6 days, and the upcoming NASA NISAR mission. We will present the progress and results we have made on automating the analysis of Sentinel-1A/B SAR data for hazard monitoring and response, with emphasis on recent developments and end user engagement in flood extent mapping and deformation time series for both volcano

  7. The body project 4 all: A pilot randomized controlled trial of a mixed-gender dissonance-based body image program.

    Science.gov (United States)

    Kilpela, Lisa Smith; Blomquist, Kerstin; Verzijl, Christina; Wilfred, Salomé; Beyl, Robbie; Becker, Carolyn Black

    2016-06-01

    The Body Project is a cognitive dissonance-based body image improvement program with ample research support among female samples. More recently, researchers have highlighted the extent of male body dissatisfaction and disordered eating behaviors; however, boys/men have not been included in the majority of body image improvement programs. This study aims to explore the efficacy of a mixed-gender Body Project compared with the historically female-only body image intervention program. Participants included male and female college students (N = 185) across two sites. We randomly assigned women to a mixed-gender modification of the two-session, peer-led Body Project (MG), the two-session, peer-led, female-only (FO) Body Project, or a waitlist control (WL), and men to either MG or WL. Participants completed self-report measures assessing negative affect, appearance-ideal internalization, body satisfaction, and eating disorder pathology at baseline, post-test, and at 2- and 6-month follow-up. Linear mixed effects modeling to estimate the change from baseline over time for each dependent variable across conditions were used. For women, results were mixed regarding post-intervention improvement compared with WL, and were largely non-significant compared with WL at 6-month follow-up. Alternatively, results indicated that men in MG consistently improved compared with WL through 6-month follow-up on all measures except negative affect and appearance-ideal internalization. Results differed markedly between female and male samples, and were more promising for men than for women. Various explanations are provided, and further research is warranted prior to drawing firm conclusions regarding mixed-gender programming of the Body Project. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2016; 49:591-602). © 2016 Wiley Periodicals, Inc.

  8. Imaging

    International Nuclear Information System (INIS)

    Kellum, C.D.; Fisher, L.M.; Tegtmeyer, C.J.

    1987-01-01

    This paper examines the advantages of the use of excretory urography for diagnosis. According to the authors, excretory urography remains the basic radiologic examination of the urinary tract and is the foundation for the evaluation of suspected urologic disease. Despite development of the newer diagnostic modalities such as isotope scanning, ultrasonography, CT, and magnetic resonsance imaging (MRI), excretory urography has maintained a prominent role in ruorradiology. Some indications have been altered and will continue to change with the newer imaging modalities, but the initial evaluation of suspected urinary tract structural abnormalities; hematuria, pyuria, and calculus disease is best performed with excretory urography. The examination is relatively inexpensive and simple to perform, with few contraindictions. Excretory urography, when properly performed, can provide valuable information about the renal parenchyma, pelvicalyceal system, ureters, and urinary bladder

  9. AquaScan: A miniaturized UV/VIS/IR hyperspectral imager for autonomous airborne and underwater imaging spectroscopy of coastal & oceanic environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The AquaScan, a miniaturized UV/VIS/NIR hyperspectral imager will be built for deployment on a UAV or small manned aircraft for ocean coastal remote sensing...

  10. A simple method for 3D lesion reconstruction from two projected angiographic images: implementation to a stereotactic radiotherapy treatment planning system

    International Nuclear Information System (INIS)

    Theodorou, K.; Kappas, C.; Gaboriaud, G.; Mazal, A.D.; Petrascu, O.; Rosenwald, J.C.

    1997-01-01

    Introduction: The most used imaging modality for diagnosis and localisation of arteriovenous malformations (AVMs) treated with stereotactic radiotherapy is angiography. The fact that the angiographic images are projected images imposes the need of the 3D reconstruction of the lesion. This, together with the 3D head anatomy from CT images could provide all the necessary information for stereotactic treatment planning. We have developed a method to combine the complementary information provided by angiography and 2D computerized tomography, matching the reconstructed AVM structure with the reconstructed head of the patient. Materials and methods: The ISIS treatment planning system, developed at Institute Curie, has been used for image acquisition, stereotactic localisation and 3D visualisation. A series of CT slices are introduced in the system as well as two orthogonal angiographic projected images of the lesion. A simple computer program has been developed for the 3D reconstruction of the lesion and for the superposition of the target contour on the CT slices of the head. Results and conclusions: In our approach we consider that the reconstruction can be made if the AVM is approximated with a number of adjacent ellipses. We assessed the method comparing the values of the reconstructed and the actual volumes of the target using linear regression analysis. For treatment planning purposes we overlapped the reconstructed AVM on the CT slices of the head. The above feature is to our knowledge a feature that the majority of the commercial stereotactic radiotherapy treatment planning system could not provide. The implementation of the method into ISIS TPS shows that we can reliably approximate and visualize the target volume

  11. The land-use projections and resulting emissions in the IPCC SRES scenarios as simulated by the IMAGE 2.2 model

    International Nuclear Information System (INIS)

    Strengers, B.; Eickhout, B.; De Vries, B.; Bouwman, L.; Leemans, R.

    2005-01-01

    The Intergovernmental Panel on Climate Change (IPCC) developed a new series of emission scenarios (SRES). Six global models were used to develop SRES but most focused primarily on energy and industry related emissions. Land-use emissions were only covered by three models, where IMAGE included the most detailed, spatially explicit description of global land-use and land-cover dynamics. To complement their calculations the other models used land-use emission from AIM and IMAGE, leading to inconsistent estimates. Representation of the land-use emissions in SRES is therefore poor. This paper presents details on the IMAGE 2.1 land-use results to complement the SRES report. The IMAGE SRES scenarios are based on the original IPCC SRES assumptions and narratives using the latest version of IMAGE (IMAGE 2.2). IMAGE provides comprehensive emission estimates because not only emissions are addressed but also the resulting atmospheric concentrations, climate change and impacts. Additionally, in SRES the scenario assumptions were only presented and quantified for 4 'macro-regions'. The IMAGE 2.2 SRES implementation has been extended towards 17 regions. We focus on land-use aspects and show that land-related emissions not only depend on population projections but also on the temporal and spatial dynamics of different land-related sources and sinks of greenhouse gases. We also illustrate the importance of systemic feed backs and interactions in the climate system that influence land-use emissions, such as deforestation and forest regrowth, soil respiration and CO2-fertilisation

  12. Two-view digital breast tomosynthesis screening with synthetically reconstructed projection images: comparison with digital breast tomosynthesis with full-field digital mammographic images.

    Science.gov (United States)

    Skaane, Per; Bandos, Andriy I; Eben, Ellen B; Jebsen, Ingvild N; Krager, Mona; Haakenaasen, Unni; Ekseth, Ulrika; Izadi, Mina; Hofvind, Solveig; Gullien, Randi

    2014-06-01

    To compare the performance of two versions of reconstructed two-dimensional (2D) images in combination with digital breast tomosynthesis (DBT) versus the performance of standard full-field digital mammography (FFDM) plus DBT. This trial had ethical committee approval, and all participants gave written informed consent. Examinations (n = 24 901) in women between the ages of 50 and 69 years (mean age, 59.2 years) were interpreted prospectively as part of a screening trial that included independent interpretations of FFDM plus DBT and reconstructed 2D images plus DBT. Reconstructed 2D images do not require radiation exposure. Using analyses for binary data that accounted for correlated interpretations and were adjusted for reader-specific volume, two versions (initial and current) of reconstructed 2D images used during trial periods 1 (from November 22, 2010, to December 21, 2011; 12 631 women) and 2 (from January 20, 2012, to December 19, 2012; 12 270 women) were compared in terms of cancer detection and false-positive rates with the corresponding FFDM plus DBT interpretations. Cancer detection rates were 8.0, 7.4, 7.8, and 7.7 per 1000 screening examinations for FFDM plus DBT in period 1, initial reconstructed 2D images plus DBT in period 1, FFDM plus DBT in period 2, and current reconstructed 2D images plus DBT in period 2, respectively. False-positive scores were 5.3%, 4.6%, 4.6%, and 4.5%, respectively. Corresponding reader-adjusted paired comparisons of false-positive scores revealed significant differences for period 1 (P = .012) but not for period 2 (ratio = 0.99; 95% confidence interval: 0.88, 1.11; P = .85). The combination of current reconstructed 2D images and DBT performed comparably to FFDM plus DBT and is adequate for routine clinical use when interpreting screening mammograms.

  13. 3D SPECT/CT fusion using image data projection of bone SPECT onto 3D volume-rendered CT images: feasibility and clinical impact in the diagnosis of bone metastasis.

    Science.gov (United States)

    Ogata, Yuji; Nakahara, Tadaki; Ode, Kenichi; Matsusaka, Yohji; Katagiri, Mari; Iwabuchi, Yu; Itoh, Kazunari; Ichimura, Akira; Jinzaki, Masahiro

    2017-05-01

    We developed a method of image data projection of bone SPECT into 3D volume-rendered CT images for 3D SPECT/CT fusion. The aims of our study were to evaluate its feasibility and clinical usefulness. Whole-body bone scintigraphy (WB) and SPECT/CT scans were performed in 318 cancer patients using a dedicated SPECT/CT systems. Volume data of bone SPECT and CT were fused to obtain 2D SPECT/CT images. To generate our 3D SPECT/CT images, colored voxel data of bone SPECT were projected onto the corresponding location of the volume-rendered CT data after a semi-automatic bone extraction. Then, the resultant 3D images were blended with conventional volume-rendered CT images, allowing to grasp the three-dimensional relationship between bone metabolism and anatomy. WB and SPECT (WB + SPECT), 2D SPECT/CT fusion, and 3D SPECT/CT fusion were evaluated by two independent reviewers in the diagnosis of bone metastasis. The inter-observer variability and diagnostic accuracy in these three image sets were investigated using a four-point diagnostic scale. Increased bone metabolism was found in 744 metastatic sites and 1002 benign changes. On a per-lesion basis, inter-observer agreements in the diagnosis of bone metastasis were 0.72 for WB + SPECT, 0.90 for 2D SPECT/CT, and 0.89 for 3D SPECT/CT. Receiver operating characteristic analyses for the diagnostic accuracy of bone metastasis showed that WB + SPECT, 2D SPECT/CT, and 3D SPECT/CT had an area under the curve of 0.800, 0.983, and 0.983 for reader 1, 0.865, 0.992, and 0.993 for reader 2, respectively (WB + SPECT vs. 2D or 3D SPECT/CT, p images were 241 ± 75, 225 ± 73, and 182 ± 71 s for reader 1 and 207 ± 72, 190 ± 73, and 179 ± 73 s for reader 2, respectively. As a result, it took shorter time to read 3D SPECT/CT images than 2D SPECT/CT (p images (p reading time compared to 2D SPECT/CT fusion.

  14. The ATLAS3D project - XXIX. The new look of early-type galaxies and surrounding fields disclosed by extremely deep optical images

    Science.gov (United States)

    Duc, Pierre-Alain; Cuillandre, Jean-Charles; Karabal, Emin; Cappellari, Michele; Alatalo, Katherine; Blitz, Leo; Bournaud, Frédéric; Bureau, Martin; Crocker, Alison F.; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Emsellem, Eric; Khochfar, Sadegh; Krajnović, Davor; Kuntschner, Harald; McDermid, Richard M.; Michel-Dansac, Leo; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Paudel, Sanjaya; Sarzi, Marc; Scott, Nicholas; Serra, Paolo; Weijmans, Anne-Marie; Young, Lisa M.

    2015-01-01

    Galactic archaeology based on star counts is instrumental to reconstruct the past mass assembly of Local Group galaxies. The development of new observing techniques and data reduction, coupled with the use of sensitive large field of view cameras, now allows us to pursue this technique in more distant galaxies exploiting their diffuse low surface brightness (LSB) light. As part of the ATLAS3D project, we have obtained with the MegaCam camera at the Canada-France-Hawaii Telescope extremely deep, multiband images of nearby early-type galaxies (ETGs). We present here a catalogue of 92 galaxies from the ATLAS3D sample, which are located in low- to medium-density environments. The observing strategy and data reduction pipeline, which achieve a gain of several magnitudes in the limiting surface brightness with respect to classical imaging surveys, are presented. The size and depth of the survey are compared to other recent deep imaging projects. The paper highlights the capability of LSB-optimized surveys at detecting new prominent structures that change the apparent morphology of galaxies. The intrinsic limitations of deep imaging observations are also discussed, among those, the contamination of the stellar haloes of galaxies by extended ghost reflections, and the cirrus emission from Galactic dust. The detection and systematic census of fine structures that trace the present and past mass assembly of ETGs are one of the prime goals of the project. We provide specific examples of each type of observed structures - tidal tails, stellar streams and shells - and explain how they were identified and classified. We give an overview of the initial results. The detailed statistical analysis will be presented in future papers.

  15. One-Sided 3D Imaging of Non-Uniformities in Non-Metallic Space Flight Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II project, we propose to develop, construct, and deliver to NASA a prototype single-sided computed tomography time-domain terahertz (single-sided CT...

  16. "Anatomy and imaging": 10 years of experience with an interdisciplinary teaching project in preclinical medical education - from an elective to a curricular course.

    Science.gov (United States)

    Schober, A; Pieper, C C; Schmidt, R; Wittkowski, W

    2014-05-01

    Presentation of an interdisciplinary, interactive, tutor-based preclinical teaching project called "Anatomy and Imaging". Experience report, analysis of evaluation results and selective literature review. From 2001 to 2012, 618 students took the basic course (4 periods per week throughout the semester) and 316 took the advanced course (2 periods per week). We reviewed 557 (return rate 90.1 %) and 292 (92.4 %) completed evaluation forms of the basic and the advanced course. Results showed overall high satisfaction with the courses (1.33 and 1.56, respectively, on a 5-point Likert scale). The recognizability of the relevance of the course content for medical training, the promotion of the interest in medicine and the quality of the student tutors were evaluated especially positively. The "Anatomy and Imaging" teaching project is a successful concept for integrating medical imaging into the preclinical stage of medical education. The course was offered as part of the curriculum in 2013 for the first time. "Anatomia in mortuis" and "Anatomia in vivo" are not regarded as rivaling entities in the delivery of knowledge, but as complementary methods. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Alternative Imaging Modalities in Ischemic Heart Failure (AIMI-HF) IMAGE HF Project I-A: study protocol for a randomized controlled trial

    OpenAIRE

    O?Meara, Eileen; Mielniczuk, Lisa M; Wells, George A; deKemp, Robert A; Klein, Ran; Coyle, Doug; Mc Ardle, Brian; Paterson, Ian; White, James A; Arnold, Malcolm; Friedrich, Matthias G; Larose, Eric; Dick, Alexander; Chow, Benjamin; Dennie, Carole

    2013-01-01

    This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Ischemic heart disease (IHD) is the most common cause of heart failure (HF); however, the role of revascularization in these patients is still unclear. Consensus on proper use of cardiac imaging to help determ...

  18. The Mircen project, neuro-degenerative disease: mechanisms, therapeutics and imaging research Unit URA Cea Cnrs 2210

    International Nuclear Information System (INIS)

    Hantraye, Ph.

    2006-01-01

    During the post-genomic era, significant advances in our understanding of the molecular basis of disease have been made. The power of functional and molecular imaging in translating this knowledge into effective therapy is now being more and more recognized. Thus, molecular imaging plays a vital role in the early identification of disease-related molecular markers, in the development of molecular-targeted therapies, and in monitoring phenotypic response to therapy both in experimental animals and in human patients. In this context, MIRCen (acronym for Molecular Imaging Research Center ) provides a comprehensive resource available to empower basic, translational, and clinical research through the application of imaging and drug, cell, and gene based technologies. The MIR center will be dedicated to the development of pre-clinical trials for the treatment of various seriously debilitating diseases such as neuro-degenerative diseases, cardiac and hepatic disorders, and infectious diseases (AIDS). Despite the fact that many of these pathologies are still incurable, recent advances in drug, cell and gene therapy point to the feasibility of new therapeutic approaches. The long term goals of MIRCen are therefore to develop and validate: - pertinent animal models for neuro-degenerative, hepatic, cardiac and infectious diseases in rodents as well as non-human primates, - novel technologies for in vivo sensing and imaging of disease-related molecular events,- drug, gene and cell based palliative and or curative therapeutic strategies aiming at protecting and /or restoring damaged or lost functions. (author)

  19. Mitigating artifacts in back-projection source imaging with implications for frequency-dependent properties of the Tohoku-Oki earthquake

    Science.gov (United States)

    Meng, Lingsen; Ampuero, Jean-Paul; Luo, Yingdi; Wu, Wenbo; Ni, Sidao

    2012-12-01

    Comparing teleseismic array back-projection source images of the 2011 Tohoku-Oki earthquake with results from static and kinematic finite source inversions has revealed little overlap between the regions of high- and low-frequency slip. Motivated by this interesting observation, back-projection studies extended to intermediate frequencies, down to about 0.1 Hz, have suggested that a progressive transition of rupture properties as a function of frequency is observable. Here, by adapting the concept of array response function to non-stationary signals, we demonstrate that the "swimming artifact", a systematic drift resulting from signal non-stationarity, induces significant bias on beamforming back-projection at low frequencies. We introduce a "reference window strategy" into the multitaper-MUSIC back-projection technique and significantly mitigate the "swimming artifact" at high frequencies (1 s to 4 s). At lower frequencies, this modification yields notable, but significantly smaller, artifacts than time-domain stacking. We perform extensive synthetic tests that include a 3D regional velocity model for Japan. We analyze the recordings of the Tohoku-Oki earthquake at the USArray and at the European array at periods from 1 s to 16 s. The migration of the source location as a function of period, regardless of the back-projection methods, has characteristics that are consistent with the expected effect of the "swimming artifact". In particular, the apparent up-dip migration as a function of frequency obtained with the USArray can be explained by the "swimming artifact". This indicates that the most substantial frequency-dependence of the Tohoku-Oki earthquake source occurs at periods longer than 16 s. Thus, low-frequency back-projection needs to be further tested and validated in order to contribute to the characterization of frequency-dependent rupture properties.

  20. Considering a pedagogy of adress through the time image: a philosophical, curational and pedagogic project centered on artium’s collection

    Directory of Open Access Journals (Sweden)

    Laura Trafí-Prats

    2013-06-01

    Full Text Available The article analyzes the foundations and research process of a curatorial-pedagogic project centered on reactivating ARTIUM’s Collection (Vitoria, Spain. In this process art and pedagogy are seen as scenes of address, or spaces of production of difference between the positions that the cultural, museum, curricular text offers, and the responses given by its interpreters, students, viewers. Different moments of this research process are discussed, including: 1 The reactivation of the expressive languages of ARTIUMartworks through a Deleuzian image theory and a pedagogy of address, 2 the production of a dilemmatic museum space centered on producing knowledge from visitors’ memories, experiences and subjectivities, 3 the activation of this space through a Laboratory of Logics of Vision, 4 the production of visual narratives experimenting with the concept of image-time by the participants in such Laboratory.

  1. Improvement in image quality. Results of a pilot project coordinated by the International Atomic Energy Agency in the Republic of Moldova

    International Nuclear Information System (INIS)

    Kaplanis, P.A.; Rehani, M.M.; Chupov, A.; ); Bahnarel, I.; Roshka, A.; Catrinici, V.; Rabovila, E.; Donos, V.; Guzun, E.; Crivoi, V.

    2005-01-01

    The objective of this Pilot Project was to perform reanalysis and image quality checks, pin point problems, suggest methods of improvement. Seven departments/rooms participated in the study. The work was conducted in two phases. A total of 1538 films were evaluated over the period of May, 12-23 2003. The films were first evaluated by a radiographer and the reject rate at radiographer level was estimated. After the data of the analysis was collected, the experts of the IAEA evaluated the results. They identified suggestions for each department, based on the results and the aim of improvement of the image quality. This was called the Quality Control (QC) step and required different levels of emphasis to parameters i different hospitals. After each department adopted the QC actions, the image quality analysis was performed once again to investigate whether or not the suggestions helped towards the improvement of image quality. In this phase 1411 films were evaluated during the period of 09.22.2003-10.03.2003. Review of the first phase results indicated that the following causes contributed to poor quality films: kVp error, improper collimation, radiation output problems, scratchers due to hanger, intensifying screen problems, improper processing, finger marks and darkroom light leak. Corrective actions, qualitative control steps, were suggested on these factors. (authors)

  2. Portable Wideband Microwave Imaging System for Intracranial Hemorrhage Detection Using Improved Back-projection Algorithm with Model of Effective Head Permittivity

    Science.gov (United States)

    Mobashsher, Ahmed Toaha; Mahmoud, A.; Abbosh, A. M.

    2016-02-01

    Intracranial hemorrhage is a medical emergency that requires rapid detection and medication to restrict any brain damage to minimal. Here, an effective wideband microwave head imaging system for on-the-spot detection of intracranial hemorrhage is presented. The operation of the system relies on the dielectric contrast between healthy brain tissues and a hemorrhage that causes a strong microwave scattering. The system uses a compact sensing antenna, which has an ultra-wideband operation with directional radiation, and a portable, compact microwave transceiver for signal transmission and data acquisition. The collected data is processed to create a clear image of the brain using an improved back projection algorithm, which is based on a novel effective head permittivity model. The system is verified in realistic simulation and experimental environments using anatomically and electrically realistic human head phantoms. Quantitative and qualitative comparisons between the images from the proposed and existing algorithms demonstrate significant improvements in detection and localization accuracy. The radiation and thermal safety of the system are examined and verified. Initial human tests are conducted on healthy subjects with different head sizes. The reconstructed images are statistically analyzed and absence of false positive results indicate the efficacy of the proposed system in future preclinical trials.

  3. Subsurface geometry of the San Andreas fault in southern California: Results from the Salton Seismic Imaging Project (SSIP) and strong ground motion expectations

    Science.gov (United States)

    Fuis, Gary S.; Bauer, Klaus; Goldman, Mark R.; Ryberg, Trond; Langenheim, Victoria; Scheirer, Daniel S.; Rymer, Michael J.; Stock, Joann M.; Hole, John A.; Catchings, Rufus D.; Graves, Robert; Aagaard, Brad T.

    2017-01-01

    The San Andreas fault (SAF) is one of the most studied strike‐slip faults in the world; yet its subsurface geometry is still uncertain in most locations. The Salton Seismic Imaging Project (SSIP) was undertaken to image the structure surrounding the SAF and also its subsurface geometry. We present SSIP studies at two locations in the Coachella Valley of the northern Salton trough. On our line 4, a fault‐crossing profile just north of the Salton Sea, sedimentary basin depth reaches 4 km southwest of the SAF. On our line 6, a fault‐crossing profile at the north end of the Coachella Valley, sedimentary basin depth is ∼2–3  km">∼2–3  km and centered on the central, most active trace of the SAF. Subsurface geometry of the SAF and nearby faults along these two lines is determined using a new method of seismic‐reflection imaging, combined with potential‐field studies and earthquakes. Below a 6–9 km depth range, the SAF dips ∼50°–60°">∼50°–60° NE, and above this depth range it dips more steeply. Nearby faults are also imaged in the upper 10 km, many of which dip steeply and project to mapped surface fault traces. These secondary faults may join the SAF at depths below about 10 km to form a flower‐like structure. In Appendix D, we show that rupture on a northeast‐dipping SAF, using a single plane that approximates the two dips seen in our study, produces shaking that differs from shaking calculated for the Great California ShakeOut, for which the southern SAF was modeled as vertical in most places: shorter‐period (TTfault.

  4. Education, Politics and Sino-Japanese Relations: Reflections on a Three-Year Project on "East Asian Images of Japan"

    Science.gov (United States)

    Vickers, Edward

    2014-01-01

    Drawing on a recent collaborative and interdisciplinary study of East Asian Images of Japan, this article discusses contemporary Chinese portrayals of Japan, their political context, and their significance for Sino-Japanese relations. It questions some widely-held assumptions concerning the extent of "thought control" in an authoritarian…

  5. Three-dimensional imaging analysis of Yersinia ruckeri infected rainbow trout (Oncorhynchus mykiss) gills by optical projection tomography

    DEFF Research Database (Denmark)

    Otani, Maki; Raida, Martin Kristian

    incubated whole with rabbit anti-Y. ruckeri polyclonal antibody and Alexa Fluor®594 conjugated goat anti-rabbit IgG. After embedding in 1% low melting point agarose, specimens were dehydrated in 100% methanol and cleared in BABB (benzyl alcohol: benzyl benzoate) for OPT scanning. 3D imaging results showed...

  6. ''Augmented reality'' in conventional simulation by projection of 3-D structures into 2-D images. A comparison with virtual methods

    International Nuclear Information System (INIS)

    Deutschmann, H.; Nairz, O.; Zehentmayr, F.; Fastner, G.; Sedlmayer, F.; Steininger, P.; Kopp, P.; Merz, F.; Wurstbauer, K.; Kranzinger, M.; Kametriser, G.; Kopp, M.

    2008-01-01

    Background and purpose: in this study, a new method is introduced, which allows the overlay of three-dimensional structures, that have been delineated on transverse slices, onto the fluoroscopy from conventional simulators in real time. Patients and methods: setup deviations between volumetric imaging and simulation were visualized, measured and corrected for 701 patient isocenters. Results: comparing the accuracy to mere virtual simulation lacking additional X-ray imaging, a clear benefit of the new method could be shown. On average, virtual prostate simulations had to be corrected by 0.48 cm (standard deviation [SD] 0.38), and those of the breast by 0.67 cm (SD 0.66). Conclusion: the presented method provides an easy way to determine entity-specific safety margins related to patient setup errors upon registration of bony anatomy (prostate 0.9 cm for 90% of cases, breast 1.3 cm). The important role of planar X-ray imaging was clearly demonstrated. The innovation can also be applied to adaptive image-guided radiotherapy (IGRT) protocols. (orig.)

  7. Short Project-Based Learning with MATLAB Applications to Support the Learning of Video-Image Processing

    Science.gov (United States)

    Gil, Pablo

    2017-01-01

    University courses concerning Computer Vision and Image Processing are generally taught using a traditional methodology that is focused on the teacher rather than on the students. This approach is consequently not effective when teachers seek to attain cognitive objectives involving their students' critical thinking. This manuscript covers the…

  8. Generation of biomechanics three-dimensional image for development of projects of custom implants in titanium alloy

    International Nuclear Information System (INIS)

    Gregolin, Rafael Ferreira; Zavaglia, Cecilia Amelia de Camargo; Tokimatsu, Ruis Camargo; Joao Antonio Pereira

    2014-01-01

    Three-dimensional modeling is an indispensable tool in manufacturing biomodels. Only after the development of a 3D design can be produced, by rapid prototyping, CNC machining, identical models of the areas of the human body. To perform computational numerical analysis is essential the creation of three-dimensional models. To Custom prostheses the use of the image of the deployment region for the development of customized implant is extremely important because it assists in the process. Only with the 3D design of the deployment region is achieved by testing and improving the designer of the prosthesis with great perfection. In the study presented here was developed a three-dimensional modeling of the jaw of a patient by computed tomography (CT) of the skull of the same . The Invesalius software was used, from the files generated by CT, to create a 3D picture of the skull. This image was exported in STL format for Rhinoceros® software to be cleaned, smoothed and separate the region of interest. After working in Rhinoceros® the image was transformed into a NURBS solid and saved in IGES format. This extension (IGES) was chosen to export the image to the Ansys Workbench® software and thus perform a static structural finite element analysis by applying own forces and fixations of human anatomy. The greatest stress found in the mandible was 213.59 MPa. (author)

  9. Role of multiparametric magnetic resonance imaging (MRI) in focal therapy for prostate cancer: a Delphi consensus project

    NARCIS (Netherlands)

    Muller, Berrend G.; van den Bos, Willemien; Brausi, Maurizio; Cornud, Francois; Gontero, Paolo; Kirkham, Alexander; Pinto, Peter A.; Polascik, Thomas J.; Rastinehad, Ardeshir R.; de Reijke, Theo M.; de la Rosette, Jean J.; Ukimura, Osamu; Villers, Arnauld; Walz, Jochen; Wijkstra, Hessel; Marberger, Michael

    2014-01-01

    To define the role of multiparametric MRI (mpMRI) for treatment planning, guidance and follow-up in focal therapy for prostate cancer based on a multidisciplinary Delphi consensus project. An online consensus process based on a questionnaire was circulated according to the Delphi method. Discussion

  10. Image quality of ct angiography using model-based iterative reconstruction in infants with congenital heart disease: Comparison with filtered back projection and hybrid iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Qianjun, E-mail: jiaqianjun@126.com [Southern Medical University, Guangzhou, Guangdong (China); Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Department of Catheterization Lab, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Zhuang, Jian, E-mail: zhuangjian5413@tom.com [Department of Cardiac Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Jiang, Jun, E-mail: 81711587@qq.com [Department of Radiology, Shenzhen Second People’s Hospital, Shenzhen, Guangdong (China); Li, Jiahua, E-mail: 970872804@qq.com [Department of Catheterization Lab, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Huang, Meiping, E-mail: huangmeiping_vip@163.com [Department of Catheterization Lab, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Southern Medical University, Guangzhou, Guangdong (China); Liang, Changhong, E-mail: cjr.lchh@vip.163.com [Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong (China); Southern Medical University, Guangzhou, Guangdong (China)

    2017-01-15

    Purpose: To compare the image quality, rate of coronary artery visualization and diagnostic accuracy of 256-slice multi-detector computed tomography angiography (CTA) with prospective electrocardiographic (ECG) triggering at a tube voltage of 80 kVp between 3 reconstruction algorithms (filtered back projection (FBP), hybrid iterative reconstruction (iDose{sup 4}) and iterative model reconstruction (IMR)) in infants with congenital heart disease (CHD). Methods: Fifty-one infants with CHD who underwent cardiac CTA in our institution between December 2014 and March 2015 were included. The effective radiation doses were calculated. Imaging data were reconstructed using the FBP, iDose{sup 4} and IMR algorithms. Parameters of objective image quality (noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR)); subjective image quality (overall image quality, image noise and margin sharpness); coronary artery visibility; and diagnostic accuracy for the three algorithms were measured and compared. Results: The mean effective radiation dose was 0.61 ± 0.32 mSv. Compared to FBP and iDose{sup 4}, IMR yielded significantly lower noise (P < 0.01), higher SNR and CNR values (P < 0.01), and a greater subjective image quality score (P < 0.01). The total number of coronary segments visualized was significantly higher for both iDose{sup 4} and IMR than for FBP (P = 0.002 and P = 0.025, respectively), but there was no significant difference in this parameter between iDose{sup 4} and IMR (P = 0.397). There was no significant difference in the diagnostic accuracy between the FBP, iDose{sup 4} and IMR algorithms (χ{sup 2} = 0.343, P = 0.842). Conclusions: For infants with CHD undergoing cardiac CTA, the IMR reconstruction algorithm provided significantly increased objective and subjective image quality compared with the FBP and iDose{sup 4} algorithms. However, IMR did not improve the diagnostic accuracy or coronary artery visualization compared with iDose{sup 4}.

  11. The use of 3D contrast-enhanced CT reconstructions to project images of vascular rings and coarctation of the aorta.

    Science.gov (United States)

    Di Sessa, Thomas G; Di Sessa, Peter; Gregory, Bill; Vranicar, Mark

    2009-01-01

    Aortic arch and pulmonary artery anomalies make up a group of vascular structures that have complex three-dimensional (3D) shapes. Tortuosity as well as hypoplasia or atresia of segments of the aortic arch or pulmonary artery makes the conventional two-dimensional (2D) imaging difficult. Nine patients with native coarctation or recoarctation and 4 patients with a vascular ring had a CT scan as a part of their clinical evaluation. There were 7 males. The mean age was 11.7 years. (range 19 days to 29 years) The mean weight was 22.7 kg (range 3.3-139.0 kg). The dicom data from contrast CT scans were converted by the Amira software package into a 3D image. The areas of interest were selected. The images were then projected in 3D on a standard video monitor and could be rotated 360 degrees in any dimension. Adequate CT scans and 3D reconstructions were obtained in 12 of 13 patients. There were 85-1,044 slices obtained in the adequate studies. We could not reconstruct a 3D image from a patient's CT scan that had only 22 slices. The anatomy defined by 3D was compared to 2D CT imaging and confirmed by cardiac catheterization or direct visualization in the operating room in the 12 patients with adequate 3D reconstructions. In 5 of 12 patients, 3D reconstructions provided valuable spatial information not observed in the conventional 2D scans. We believe that 3D reconstruction of contrast-enhanced CT scans of these complex structures provides additional valuable information that is helpful in the decision-making process.

  12. Bringing Authentic Research into the Classroom with the Mars Student Imaging Project: Comparison of the PBL Gold Standards to the Scientific Methods

    Science.gov (United States)

    Pounder, Jean

    2017-04-01

    The goal of Project Based Learning (PBL) is to actively engage students through authentic, real word study to increase content knowledge, understanding, and skills for everyday success. The essential design of PBL is very similar in nature to the scientific method and therefore easy to adapt to the science classroom. In my classroom, students use these essential elements when engaging in the study of the processes that affect the surface of a planet such as weathering and erosion. Studying Mars is a hook to getting students to learn about the same processes that occur on Earth and to contrast the differences that occur on another planetary body. As part of the Mars Student Imaging Project (MSIP), students have the opportunity to engage and collaborate with NASA scientists at Arizona State University and get feedback on their work. They research and develop their own question or area of focus to study. They use images of Mars taken using the THEMIS camera onboard the Mars Odyssey Satellite, which has been orbiting Mars since 2001. Students submit a proposal to the scientists at ASU and, if accepted, they are given the opportunity to use the THEMIS camera in orbit to photograph a new region on Mars that will hopefully contribute to their research. Students give a final presentation to the faculty, staff, community, and other students by presenting their work in a poster session and explaining their work to the audience.

  13. Live image processing does not increase adenoma detection rate during colonoscopy: a randomized comparison between FICE and conventional imaging (Berlin Colonoscopy Project 5, BECOP-5).

    Science.gov (United States)

    Aminalai, Alireza; Rösch, Thomas; Aschenbeck, Jens; Mayr, Michael; Drossel, Rolf; Schröder, Andreas; Scheel, Matthias; Treytnar, Doris; Gauger, Ulrich; Stange, Gabriela; Simon, Frank; Adler, Andreas

    2010-11-01

    Fujinon intelligent chromoendoscopy (FICE) is a post-processing imaging technique for increasing contrast of mucosa and mucosal lesions that might lead to improvement in colonic adenoma detection during colonoscopy. Previous studies on similar contrast-enhancing techniques as well as on dye staining have yielded variable and conflicting results. This large randomized trial was undertaken to determine whether FICE technology enhances adenoma detection rate (ADR). In a prospective study performed in a multicenter private practice and hospital setting, involving 8 examiners with substantial lifetime experience (>10,000 colonoscopies each), 1,318 patients (men 46.7%, women 53.3%; mean age 59.05 years) were randomly assigned to colonoscopy with either FICE or white light imaging on instrument withdrawal. Of the colonoscopies, 68% were screening and 32% were diagnostic examinations. The primary outcome measure was the ADR (i.e., number of adenomas/total number of patients). There was no difference between the two groups in terms of general ADR (0.28 in both groups), the total number of adenomas (184 vs. 183), or detection of subgroups of adenomas. The rate of identification of hyperplastic polyps was also the same in both groups (127 vs. 121; P=0.67). The results were the same for both the screening and the diagnostic colonoscopy subgroups. Withdrawal time was the same in both groups (8.4 vs. 8.3 min, P=0.55). This large randomized trial could not show any objective advantage of the FICE technique over conventional high-resolution endoscopy in terms of improved ADR.

  14. The Advanced Rapid Imaging and Analysis (ARIA) Project: Providing Standard and On-Demand SAR products for Hazard Science and Hazard Response

    Science.gov (United States)

    Owen, S. E.; Hua, H.; Rosen, P. A.; Agram, P. S.; Webb, F.; Simons, M.; Yun, S. H.; Sacco, G. F.; Liu, Z.; Fielding, E. J.; Lundgren, P.; Moore, A. W.

    2017-12-01

    A new era of geodetic imaging arrived with the launch of the ESA Sentinel-1A/B satellites in 2014 and 2016, and with the 2016 confirmation of the NISAR mission, planned for launch in 2021. These missions assure high quality, freely and openly distributed regularly sampled SAR data into the indefinite future. These unprecedented data sets are a watershed for solid earth sciences as we progress towards the goal of ubiquitous InSAR measurements. We now face the challenge of how to best address the massive volumes of data and intensive processing requirements. Should scientists individually process the same data independently themselves? Should a centralized service provider create standard products that all can use? Are there other approaches to accelerate science that are cost effective and efficient? The Advanced Rapid Imaging and Analysis (ARIA) project, a joint venture co-sponsored by California Institute of Technology (Caltech) and by NASA through the Jet Propulsion Laboratory (JPL), is focused on rapidly generating higher level geodetic imaging products and placing them in the hands of the solid earth science and local, national, and international natural hazard communities by providing science product generation, exploration, and delivery capabilities at an operational level. However, there are challenges in defining the optimal InSAR data products for the solid earth science community. In this presentation, we will present our experience with InSAR users, our lessons learned the advantages of on demand and standard products, and our proposal for the most effective path forward.

  15. Adequacy of source to image receptor distance with chest postero-anterior projection in digital radiology system

    International Nuclear Information System (INIS)

    Joo, Young Cheol; Lim, Cheong Hwan; Jung, Hong Ryang; You, In Gyu; Lee, Sang Ho

    2016-01-01

    The purpose of this study is to evaluate propriety of using SID 180cm at Chest PA examination and to find effect of geometrical cause to the image. XGEO-GC80, INNOVISION-SH, CXDI-40EG detector and a chest phantom designed self-production was used for this study. Images were acquired at SID 180cm with changing the factor OID as 0, 75 and 83mm and were analyzed by Centricity Radiography RA1000 PACS system. Statistical program was used the SPSS (Version 22.0, SPSS, Chicago, IL, USA), p-value(under 0.05) was considered to be statistically significant. In OID 0 mm was enlarged about 2.7⁓3.5 mm than the actual degree of the HS, BS of phantom in all equipments. Compared with the calculated magnification has been expanded 1.6⁓2.8% when viewed. The OID 75 mm with OID 83 mm was extended from the CS and BS 6⁓8 mm range. Compared to the calculated values, the measured values are expanded from 6.1 to 7.9%. CS and BS according to the OID change showed a statistically significant difference (p<0.05) among each group, the post-analysis only OID 0 mm group appeared as an independent group, 75 mm and 83 mm are separated in the same group It was. But had no statistically significant difference could change depending on the OID (p>0.05), post-mortem analysis showed, both in the same group. Heart sizes appears larger than actual size 6⁓8 mm at chest PA examination which is enlarged 6.1~7.9% more than the actual theoretical value. We can find magnification of the image because of the increase of the OID due to technical limitations between cover of standing detector and the image plate. so we suggest to have occurred between them when considering the need to adjust the equipment installed by the SID to match the characteristics of the equipment

  16. Adequacy of source to image receptor distance with chest postero-anterior projection in digital radiology system

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Cheol [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Lim, Cheong Hwan; Jung, Hong Ryang [Dept. of Radiology, Science, Hanseo University, Seosan (Korea, Republic of); You, In Gyu [Dept. of Radiology, Hallym University Hospital, Chuncheon (Korea, Republic of); Lee, Sang Ho [Dept. of Radiology, Science, Seonam University, Namwon (Korea, Republic of)

    2016-06-15

    The purpose of this study is to evaluate propriety of using SID 180cm at Chest PA examination and to find effect of geometrical cause to the image. XGEO-GC80, INNOVISION-SH, CXDI-40EG detector and a chest phantom designed self-production was used for this study. Images were acquired at SID 180cm with changing the factor OID as 0, 75 and 83mm and were analyzed by Centricity Radiography RA1000 PACS system. Statistical program was used the SPSS (Version 22.0, SPSS, Chicago, IL, USA), p-value(under 0.05) was considered to be statistically significant. In OID 0 mm was enlarged about 2.7⁓3.5 mm than the actual degree of the HS, BS of phantom in all equipments. Compared with the calculated magnification has been expanded 1.6⁓2.8% when viewed. The OID 75 mm with OID 83 mm was extended from the CS and BS 6⁓8 mm range. Compared to the calculated values, the measured values are expanded from 6.1 to 7.9%. CS and BS according to the OID change showed a statistically significant difference (p<0.05) among each group, the post-analysis only OID 0 mm group appeared as an independent group, 75 mm and 83 mm are separated in the same group It was. But had no statistically significant difference could change depending on the OID (p>0.05), post-mortem analysis showed, both in the same group. Heart sizes appears larger than actual size 6⁓8 mm at chest PA examination which is enlarged 6.1~7.9% more than the actual theoretical value. We can find magnification of the image because of the increase of the OID due to technical limitations between cover of standing detector and the image plate. so we suggest to have occurred between them when considering the need to adjust the equipment installed by the SID to match the characteristics of the equipment.

  17. Image-Based Virtual Tours and 3d Modeling of Past and Current Ages for the Enhancement of Archaeological Parks: the Visualversilia 3d Project

    Science.gov (United States)

    Castagnetti, C.; Giannini, M.; Rivola, R.

    2017-05-01

    The research project VisualVersilia 3D aims at offering a new way to promote the territory and its heritage by matching the traditional reading of the document and the potential use of modern communication technologies for the cultural tourism. Recently, the research on the use of new technologies applied to cultural heritage have turned their attention mainly to technologies to reconstruct and narrate the complexity of the territory and its heritage, including 3D scanning, 3D printing and augmented reality. Some museums and archaeological sites already exploit the potential of digital tools to preserve and spread their heritage but interactive services involving tourists in an immersive and more modern experience are still rare. The innovation of the project consists in the development of a methodology for documenting current and past historical ages and integrating their 3D visualizations with rendering capable of returning an immersive virtual reality for a successful enhancement of the heritage. The project implements the methodology in the archaeological complex of Massaciuccoli, one of the best preserved roman site of the Versilia Area (Tuscany, Italy). The activities of the project briefly consist in developing: 1. the virtual tour of the site in its current configuration on the basis of spherical images then enhanced by texts, graphics and audio guides in order to enable both an immersive and remote tourist experience; 2. 3D reconstruction of the evidences and buildings in their current condition for documentation and conservation purposes on the basis of a complete metric survey carried out through laser scanning; 3. 3D virtual reconstructions through the main historical periods on the basis of historical investigation and the analysis of data acquired.

  18. IMAGE-BASED VIRTUAL TOURS AND 3D MODELING OF PAST AND CURRENT AGES FOR THE ENHANCEMENT OF ARCHAEOLOGICAL PARKS: THE VISUALVERSILIA 3D PROJECT

    Directory of Open Access Journals (Sweden)

    C. Castagnetti

    2017-05-01

    Full Text Available The research project VisualVersilia 3D aims at offering a new way to promote the territory and its heritage by matching the traditional reading of the document and the potential use of modern communication technologies for the cultural tourism. Recently, the research on the use of new technologies applied to cultural heritage have turned their attention mainly to technologies to reconstruct and narrate the complexity of the territory and its heritage, including 3D scanning, 3D printing and augmented reality. Some museums and archaeological sites already exploit the potential of digital tools to preserve and spread their heritage but interactive services involving tourists in an immersive and more modern experience are still rare. The innovation of the project consists in the development of a methodology for documenting current and past historical ages and integrating their 3D visualizations with rendering capable of returning an immersive virtual reality for a successful enhancement of the heritage. The project implements the methodology in the archaeological complex of Massaciuccoli, one of the best preserved roman site of the Versilia Area (Tuscany, Italy. The activities of the project briefly consist in developing: 1. the virtual tour of the site in its current configuration on the basis of spherical images then enhanced by texts, graphics and audio guides in order to enable both an immersive and remote tourist experience; 2. 3D reconstruction of the evidences and buildings in their current condition for documentation and conservation purposes on the basis of a complete metric survey carried out through laser scanning; 3. 3D virtual reconstructions through the main historical periods on the basis of historical investigation and the analysis of data acquired.

  19. Radiology resident MR and CT image analysis skill assessment using an interactive volumetric simulation tool - the RadioLOG project.

    Science.gov (United States)

    Gondim Teixeira, Pedro Augusto; Cendre, Romain; Hossu, Gabriela; Leplat, Christophe; Felblinger, Jacques; Blum, Alain; Braun, Marc

    2017-02-01

    Assess the use of a volumetric simulation tool for the evaluation of radiology resident MR and CT interpretation skills. Forty-three participants were evaluated with a software allowing the visualisation of multiple volumetric image series. There were 7 medical students, 28 residents and 8 senior radiologists among the participants. Residents were divided into two sub-groups (novice and advanced). The test was composed of 15 exercises on general radiology and lasted 45 min. Participants answered a questionnaire on their experience with the test using a 5-point Likert scale. This study was approved by the dean of the medical school and did not require ethics committee approval. The reliability of the test was good with a Cronbach alpha value of 0.9. Test scores were significantly different in all sub-groups studies (p radiological practice (3.9 ± 0.9 on a 5-point scale) and was better than the conventional evaluation methods (4.6 ± 0.5 on a 5-point scale). This software provides a high quality evaluation tool for the assessment of the interpretation skills in radiology residents. • This tool allows volumetric image analysis of MR and CT studies. • A high reliability test could be created with this tool. • Test scores were strongly associated with the examinee expertise level. • Examinees positively evaluated the authenticity and usability of this tool.

  20. Endoscopic third ventriculocisternostomies in the infant: Pre- and post-operative Magnetic resonance imaging evaluation elective project undergraduate prize 2000

    Energy Technology Data Exchange (ETDEWEB)

    Sharman, Anna

    2000-12-01

    PURPOSE: To determine whether it is possible to select patients with obstructive hydrocephalus, in the under 1 age group for endoscopic third ventriculocisternostomy (ETV) using pre-operative T2 weighted turbo spin echo (T2W-TSE) sagittal sequence Magnetic Resonance (MR) imaging; and to assess ventriculocisternostomy patency using post-operative T2W-TSE MR. PATIENTS AND METHODS: A retrospective review of MR examinations and clinical notes of 11 patients under 1 year of age who had ETV, was performed. The post-operative flow MR images were divided into the presence or absence of flow-related signal changes. RESULTS: In 6 of the 11 patients, ETV was successful (54.5%) i.e. no VP shunt or revision of the ETV was required. 9 patients had post-operative T2W-TSE MR examinations -- 8 of these 9 MR studies correlated to the clinical situation (89%). The remaining MR examination showed a CSF flow void but the ETV failed at 3 weeks. CONCLUSION: Pre-operative MR using T2W-TSE to select suitable candidates for ETV improves the success rate from < 40% to 54.5%. Post-operatively MRI is a good predictor of whether the ETV has been successful or not. Sharman, A. (2000)

  1. TU-G-213-02: IEC Subcommittee 62B (Diagnostic Imaging Equipment): Recent and Active Projects

    International Nuclear Information System (INIS)

    Supanich, M.

    2015-01-01

    The International Electrotechnical Commission (IEC) writes standards that manufacturers of electrical equipment must comply with. Medical electrical equipment, such as medical imaging, radiation therapy, and radiation dosimetry devices, fall under Technical Committee 62. Of particular interest to medical physicists are the standards developed within Subcommittees (SC) 62B, which addresses diagnostic radiological imaging equipment, and 62C, which addresses equipment for radiation therapy, nuclear medicine and dosimetry. For example, a Working Group of SC 62B is responsible for safety and quality assurance standards for CT scanners and a Working Group of SC 62C is responsible for standards that set requirements for dosimetric safety and accuracy of linacs and proton accelerators. IEC standards thus have an impact on every aspect of a medical physicist’s job, including equipment testing, shielding design, room layout, and workflow. Consequently, it is imperative that US medical physicists know about existing standards, as well as have input on those under development or undergoing revision. The structure of the IEC and current standards development work will be described in detail. The presentation will explain how US medical physicists can learn about IEC standards and contribute to their development. Learning Objectives: Learn about the structure of the IEC and the influence that IEC standards have on the design of equipment for radiology and radiation therapy. Learn about the mechanisms by which the US participates in the development and revision of standards. Understand the specific requirements of several standards having direct relevance to diagnostic and radiation therapy physicists

  2. THE PROJECT: FROM THE IDEA AND APPLICATION OF THE DESIGNER TO RECEPTION A PRAGMATIC STUDY OF IMAGES ON FOOD WASTE

    Directory of Open Access Journals (Sweden)

    Mona Junger Aghababaie

    2017-02-01

    Full Text Available DOI: 10.12957/periferia.2015.18838Social posters and visual communication regarding concepts such as " public health", " civil responsibility", "responsible action" and practices connected to the reception of non commercial advertising images are the focus point of this article. Designers conceptualize and produce designs hoping that these become integrated into the cultural and social practices of their receivers. In the case of posters on food waste, our questioning is as follows: How does the designer conceptualize and create his final version? How do receivers appropriate these posters? Do these designs have the capacity to influence the receiver to a change of attitude? In an attempt to answer these questions, we met with two French designers, Axelle Roue and Hélène Petit and we questioned them on their designs on food waste, exhibited in July, 2013 in Parisian subway stations. We interviewed them on their design process, on their first versions (rough copies up to their final version. In parallel, we also questioned the receivers (the passers-by in the Parisian subway on how they felt about these posters. The objective was to discover if the meaning of the image sent to the receiver was identical to what the designer had planned in his design.

  3. Comparison of applied dose and image quality in staging CT of neuroendocrine tumor patients using standard filtered back projection and adaptive statistical iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Böning, G., E-mail: georg.boening@charite.de [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Schäfer, M.; Grupp, U. [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Kaul, D. [Department of Radiation Oncology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Kahn, J. [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Pavel, M. [Department of Gastroenterology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany); Maurer, M.; Denecke, T.; Hamm, B.; Streitparth, F. [Department of Radiology, Charité, Humboldt-University Medical School, Charitéplatz 1, 10117 Berlin (Germany)

    2015-08-15

    Highlights: • Iterative reconstruction (IR) in staging CT provides equal objective image quality compared to filtered back projection (FBP). • IR delivers excellent subjective quality and reduces effective dose compared to FBP. • In patients with neuroendocrine tumor (NET) or may other hypervascular abdominal tumors IR can be used without scarifying diagnostic confidence. - Abstract: Objective: To investigate whether dose reduction via adaptive statistical iterative reconstruction (ASIR) affects image quality and diagnostic accuracy in neuroendocrine tumor (NET) staging. Methods: A total of 28 NET patients were enrolled in the study. Inclusion criteria were histologically proven NET and visible tumor in abdominal computed tomography (CT). In an intraindividual study design, the patients underwent a baseline CT (filtered back projection, FBP) and follow-up CT (ASIR 40%) using matched scan parameters. Image quality was assessed subjectively using a 5-grade scoring system and objectively by determining signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNRs). Applied volume computed tomography dose index (CTDI{sub vol}) of each scan was taken from the dose report. Results: ASIR 40% significantly reduced CTDI{sub vol} (10.17 ± 3.06 mGy [FBP], 6.34 ± 2.25 mGy [ASIR] (p < 0.001) by 37.6% and significantly increased CNRs (complete tumor-to-liver, 2.76 ± 1.87 [FBP], 3.2 ± 2.32 [ASIR]) (p < 0.05) (complete tumor-to-muscle, 2.74 ± 2.67 [FBP], 4.31 ± 4.61 [ASIR]) (p < 0.05) compared to FBP. Subjective scoring revealed no significant changes for diagnostic confidence (5.0 ± 0 [FBP], 5.0 ± 0 [ASIR]), visibility of suspicious lesion (4.8 ± 0.5 [FBP], 4.8 ± 0.5 [ASIR]) and artifacts (5.0 ± 0 [FBP], 5.0 ± 0 [ASIR]). ASIR 40% significantly decreased scores for noise (4.3 ± 0.6 [FBP], 4.0 ± 0.8 [ASIR]) (p < 0.05), contrast (4.4 ± 0.6 [FBP], 4.1 ± 0.8 [ASIR]) (p < 0.001) and visibility of small structures (4.5 ± 0.7 [FBP], 4.3 ± 0.8 [ASIR]) (p < 0

  4. Damage methodology approach on a composite panel based on a combination of Fringe Projection and 2D Digital Image Correlation

    Science.gov (United States)

    Felipe-Sesé, Luis; Díaz, Francisco A.

    2018-02-01

    The recent improvement in accessibility to high speed digital cameras has enabled three dimensional (3D) vibration measurements employing full-field optical techniques. Moreover, there is a need to develop a cost-effective and non-destructive testing method to quantify the severity of damages arising from impacts and thus, enhance the service life. This effect is more interesting in composite structures since possible internal damage has low external manifestation. Those possible damages have been previously studied experimentally by using vibration testing. Namely, those analyses were focused on variations in the modal frequencies or, more recently, mode shapes variations employing punctual accelerometers or vibrometers. In this paper it is presented an alternative method to investigate the severity of damage on a composite structure and how the damage affects to its integrity through the analysis of the full field modal behaviour. In this case, instead of punctual measurements, displacement maps are analysed by employing a combination of FP + 2D-DIC during vibration experiments in an industrial component. In addition, to analyse possible mode shape changes, differences between damaged and undamaged specimens are studied by employing a recent methodology based on Adaptive Image Decomposition (AGMD) procedure. It will be demonstrated that AGMD Image decomposition procedure, which decompose the displacement field into shape descriptors, is capable to detect and quantify the differences between mode shapes. As an application example, the proposed approach has been evaluated on two large industrial components (car bonnets) made of short-fibre reinforced composite. Specifically, the evolution of normalized AGMD shape descriptors has been evaluated for three different components with different damage levels. Results demonstrate the potential of the presented approach making it possible to measure the severity of a structural damage by evaluating the mode shape based in

  5. Borehole-explosion and air-gun data acquired in the 2011 Salton Seismic Imaging Project (SSIP), southern California: description of the survey

    Science.gov (United States)

    Rose, Elizabeth J.; Fuis, Gary S.; Stock, Joann M.; Hole, John A.; Kell, Annie M.; Kent, Graham; Driscoll, Neal W.; Goldman, Mark; Reusch, Angela M.; Han, Liang; Sickler, Robert R.; Catchings, Rufus D.; Rymer, Michael J.; Criley, Coyn J.; Scheirer, Daniel S.; Skinner, Steven M.; Slayday-Criley, Coye J.; Murphy, Janice M.; Jensen, Edward G.; McClearn, Robert; Ferguson, Alex J.; Butcher, Lesley A.; Gardner, Max A.; Emmons, Iain; Loughran, Caleb L.; Svitek, Joseph R.; Bastien, Patrick C.; Cotton, Joseph A.; Croker, David S.; Harding, Alistair J.; Babcock, Jeffrey M.; Harder, Steven H.; Rosa, Carla M.

    2013-01-01

    The Imperial and Coachella Valleys are being formed by active plate-tectonic processes. From the Imperial Valley southward into the Gulf of California, plate motions are rifting the continent apart. In the Coachella Valley, the plates are sliding past one another along the San Andreas and related faults (fig. 1). These processes build the stunning landscapes of the region, but also produce damaging earthquakes. Rupture of the southern section of the San Andreas Fault (SAF), from the Coachella Valley to the Mojave Desert, is believed to be the greatest natural hazard that California will face in the near future. With an estimated magnitude between 7.2 and 8.1, such an event would result in violent shaking, loss of life, and disruption of infrastructure (freeways, aqueducts, power, petroleum, and communication lines) that might bring much of southern California to a standstill. As part of the nation’s efforts to avert a catastrophe of this magnitude, a number of projects have been undertaken to more fully understand and mitigate the effects of such an event. The Salton Seismic Imaging Project (SSIP), funded jointly by the National Science Foundation (NSF) and the U.S. Geological Survey (USGS), seeks to understand, through seismic imaging, the structure of the Earth surrounding the SAF, including the sedimentary basins on which cities are built. The principal investigators (PIs) of this collaborative project represent the USGS, Virginia Polytechnic Institute and State University (Virginia Tech), California Institute of Technology (Caltech), Scripps Institution of Oceanography (Scripps), University of Nevada, Reno (UNR), and Stanford University. SSIP will create images of underground structure and sediments in the Imperial and Coachella Valleys and adjacent mountain ranges to investigate the earthquake hazards posed to cities in this area. Importantly, the images will help determine the underground geometry of the SAF, how deep the sediments are, and how fast

  6. Modified Projective Synchronization between Different Fractional-Order Systems Based on Open-Plus-Closed-Loop Control and Its Application in Image Encryption

    Directory of Open Access Journals (Sweden)

    Hongjuan Liu

    2014-01-01

    Full Text Available A new general and systematic coupling scheme is developed to achieve the modified projective synchronization (MPS of different fractional-order systems under parameter mismatch via the Open-Plus-Closed-Loop (OPCL control. Based on the stability theorem of linear fractional-order systems, some sufficient conditions for MPS are proposed. Two groups of numerical simulations on the incommensurate fraction-order system and commensurate fraction-order system are presented to justify the theoretical analysis. Due to the unpredictability of the scale factors and the use of fractional-order systems, the chaotic data from the MPS is selected to encrypt a plain image to obtain higher security. Simulation results show that our method is efficient with a large key space, high sensitivity to encryption keys, resistance to attack of differential attacks, and statistical analysis.

  7. MO-G-17A-07: Improved Image Quality in Brain F-18 FDG PET Using Penalized-Likelihood Image Reconstruction Via a Generalized Preconditioned Alternating Projection Algorithm: The First Patient Results

    Energy Technology Data Exchange (ETDEWEB)

    Schmidtlein, CR; Beattie, B; Humm, J [Memorial Sloan Kettering Cancer Center, New York, NY (United States); Li, S; Wu, Z; Xu, Y [Sun Yat-sen University, Guangzhou, Guangdong (China); Zhang, J; Shen, L [Syracuse University, Syracuse, NY (United States); Vogelsang, L [VirtualScopics, Rochester, NY (United States); Feiglin, D; Krol, A [SUNY Upstate Medical University, Syracuse, NY (United States)

    2014-06-15

    Purpose: To investigate the performance of a new penalized-likelihood PET image reconstruction algorithm using the 1{sub 1}-norm total-variation (TV) sum of the 1st through 4th-order gradients as the penalty. Simulated and brain patient data sets were analyzed. Methods: This work represents an extension of the preconditioned alternating projection algorithm (PAPA) for emission-computed tomography. In this new generalized algorithm (GPAPA), the penalty term is expanded to allow multiple components, in this case the sum of the 1st to 4th order gradients, to reduce artificial piece-wise constant regions (“staircase” artifacts typical for TV) seen in PAPA images penalized with only the 1st order gradient. Simulated data were used to test for “staircase” artifacts and to optimize the penalty hyper-parameter in the root-mean-squared error (RMSE) sense. Patient FDG brain scans were acquired on a GE D690 PET/CT (370 MBq at 1-hour post-injection for 10 minutes) in time-of-flight mode and in all cases were reconstructed using resolution recovery projectors. GPAPA images were compared PAPA and RMSE-optimally filtered OSEM (fully converged) in simulations and to clinical OSEM reconstructions (3 iterations, 32 subsets) with 2.6 mm XYGaussian and standard 3-point axial smoothing post-filters. Results: The results from the simulated data show a significant reduction in the 'staircase' artifact for GPAPA compared to PAPA and lower RMSE (up to 35%) compared to optimally filtered OSEM. A simple power-law relationship between the RMSE-optimal hyper-parameters and the noise equivalent counts (NEC) per voxel is revealed. Qualitatively, the patient images appear much sharper and with less noise than standard clinical images. The convergence rate is similar to OSEM. Conclusions: GPAPA reconstructions using the 1{sub 1}-norm total-variation sum of the 1st through 4th-order gradients as the penalty show great promise for the improvement of image quality over that

  8. MO-G-17A-07: Improved Image Quality in Brain F-18 FDG PET Using Penalized-Likelihood Image Reconstruction Via a Generalized Preconditioned Alternating Projection Algorithm: The First Patient Results

    International Nuclear Information System (INIS)

    Schmidtlein, CR; Beattie, B; Humm, J; Li, S; Wu, Z; Xu, Y; Zhang, J; Shen, L; Vogelsang, L; Feiglin, D; Krol, A

    2014-01-01

    Purpose: To investigate the performance of a new penalized-likelihood PET image reconstruction algorithm using the 1 1 -norm total-variation (TV) sum of the 1st through 4th-order gradients as the penalty. Simulated and brain patient data sets were analyzed. Methods: This work represents an extension of the preconditioned alternating projection algorithm (PAPA) for emission-computed tomography. In this new generalized algorithm (GPAPA), the penalty term is expanded to allow multiple components, in this case the sum of the 1st to 4th order gradients, to reduce artificial piece-wise constant regions (“staircase” artifacts typical for TV) seen in PAPA images penalized with only the 1st order gradient. Simulated data were used to test for “staircase” artifacts and to optimize the penalty hyper-parameter in the root-mean-squared error (RMSE) sense. Patient FDG brain scans were acquired on a GE D690 PET/CT (370 MBq at 1-hour post-injection for 10 minutes) in time-of-flight mode and in all cases were reconstructed using resolution recovery projectors. GPAPA images were compared PAPA and RMSE-optimally filtered OSEM (fully converged) in simulations and to clinical OSEM reconstructions (3 iterations, 32 subsets) with 2.6 mm XYGaussian and standard 3-point axial smoothing post-filters. Results: The results from the simulated data show a significant reduction in the 'staircase' artifact for GPAPA compared to PAPA and lower RMSE (up to 35%) compared to optimally filtered OSEM. A simple power-law relationship between the RMSE-optimal hyper-parameters and the noise equivalent counts (NEC) per voxel is revealed. Qualitatively, the patient images appear much sharper and with less noise than standard clinical images. The convergence rate is similar to OSEM. Conclusions: GPAPA reconstructions using the 1 1 -norm total-variation sum of the 1st through 4th-order gradients as the penalty show great promise for the improvement of image quality over that currently

  9. Final Report on LDRD project 130784 : functional brain imaging by tunable multi-spectral Event-Related Optical Signal (EROS).

    Energy Technology Data Exchange (ETDEWEB)

    Speed, Ann Elizabeth; Spahn, Olga Blum; Hsu, Alan Yuan-Chun

    2009-09-01

    Functional brain imaging is of great interest for understanding correlations between specific cognitive processes and underlying neural activity. This understanding can provide the foundation for developing enhanced human-machine interfaces, decision aides, and enhanced cognition at the physiological level. The functional near infrared spectroscopy (fNIRS) based event-related optical signal (EROS) technique can provide direct, high-fidelity measures of temporal and spatial characteristics of neural networks underlying cognitive behavior. However, current EROS systems are hampered by poor signal-to-noise-ratio (SNR) and depth of measure, limiting areas of the brain and associated cognitive processes that can be investigated. We propose to investigate a flexible, tunable, multi-spectral fNIRS EROS system which will provide up to 10x greater SNR as well as improved spatial and temporal resolution through significant improvements in electronics, optoelectronics and optics, as well as contribute to the physiological foundation of higher-order cognitive processes and provide the technical foundation for miniaturized portable neuroimaging systems.

  10. Radiology resident MR and CT image analysis skill assessment using an interactive volumetric simulation tool - the RadioLOG project

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto; Leplat, Christophe [CHRU-Nancy Hopital Central, Service d' Imagerie Guilloz, Nancy (France); Universite de Lorraine, IADI U947, Nancy (France); Cendre, Romain [INSERM, CIC-IT 1433, Nancy (France); Hossu, Gabriela; Felblinger, Jacques [Universite de Lorraine, IADI U947, Nancy (France); INSERM, CIC-IT 1433, Nancy (France); Blum, Alain [CHRU-Nancy Hopital Central, Service d' Imagerie Guilloz, Nancy (France); Braun, Marc [CHRU-Nancy Hopital Central, Service de Neuroradiologie, Nancy (France)

    2017-02-15

    Assess the use of a volumetric simulation tool for the evaluation of radiology resident MR and CT interpretation skills. Forty-three participants were evaluated with a software allowing the visualisation of multiple volumetric image series. There were 7 medical students, 28 residents and 8 senior radiologists among the participants. Residents were divided into two sub-groups (novice and advanced). The test was composed of 15 exercises on general radiology and lasted 45 min. Participants answered a questionnaire on their experience with the test using a 5-point Likert scale. This study was approved by the dean of the medical school and did not require ethics committee approval. The reliability of the test was good with a Cronbach alpha value of 0.9. Test scores were significantly different in all sub-groups studies (p < 0.0225). The relation between test scores and the year of residency was logarithmic (R{sup 2} = 0.974). Participants agreed that the test reflected their radiological practice (3.9 ± 0.9 on a 5-point scale) and was better than the conventional evaluation methods (4.6 ± 0.5 on a 5-point scale). This software provides a high quality evaluation tool for the assessment of the interpretation skills in radiology residents. (orig.)

  11. The application of total vertical projections for the unbiased estimation of the length of blood vessels and other structures by magnetic resonance imaging.

    Science.gov (United States)

    Roberts, N; Howard, C V; Cruz-Orive, L M; Edwards, R H

    1991-01-01

    A new stereological method has recently been developed to estimate the total length of a bounded curve in 3D from a sample of projections about a vertical axis. Unlike other methods based on serial section reconstructions, the new method is unbiased (i.e., it has zero systematic error). A basic requirement, not difficult to fulfill in many cases, is that the masking of one structure by another is not appreciable. The application of the new method to real curvilinear structures using a clinical magnetic resonance (MR) imager is illustrated. The first structure measured was a twisted water-filled glass tube of known length. The accuracy of the method was assessed: With six vertical projections, the tube length was measured to within 2% of the true value. The second example was a living bonsai tree, and the third was a clinical application of MR angiography. The possibility of applying the method to other scientific disciplines, for example, the monitoring of plant root growth, is discussed.

  12. Development of kits for 99mTc radiopharmaceuticals for infection imaging. Report of a co-ordinated research project 2000-2003

    International Nuclear Information System (INIS)

    2004-09-01

    establishment of a Co-ordinated Research Project (CRP) by the IAEA. The CRP could investigate alternate biochemical pathways, promising recent advances in 99 mTc labelling methodologies and recent progress in evaluation methods. Based on recommendations of two consultants meetings, the IAEA initiated a CRP entitled Development of Kits for 99 mTc Radiopharmaceuticals for Infection Imaging in 2000. Twelve laboratories from Asia, Europe, North America, and South America participated in the CRP, which was concluded in 2003. Among the objectives of this CRP was the development of different 99 mTc labelling strategies in participating laboratories that would be useful in the development of 99 mTc labelled infection imaging agents. In addition, techniques were to be developed for the in vitro and in vivo testing of label stability. Finally, it was hoped that one or more of the identified agents would prove to localize in infection by a specific mechanism. The CRP may be said to be successful in all three measures. Finally, with the identification of 99 mTc ubiquicidine fragment (UBI 29-41) as a radiolabelled agent with potential clinical utility, this CRP can be considered to have made a major contribution by providing the first validated specific 99 mTc labelled infection imaging agent

  13. Project 2010 Project Management

    CERN Document Server

    Happy, Robert

    2010-01-01

    The ideal on-the-job reference guide for project managers who use Microsoft Project 2010. This must-have guide to using Microsoft Project 2010 is written from a real project manager's perspective and is packed with information you can use on the job. The book explores using Project 2010 during phases of project management, reveals best practices, and walks you through project flow from planning through tracking to closure. This valuable book follows the processes defined in the PMBOK Guide, Fourth Edition , and also provides exam prep for Microsoft's MCTS: Project 2010 certification.: Explains

  14. Rupture imaging of the Mw 7.9 12 May 2008 Wenchuan earthquake from back projection of teleseismic P waves

    Science.gov (United States)

    Xu, Yan; Koper, Keith D.; Sufri, Oner; Zhu, Lupei; Hutko, Alexander R.

    2009-04-01

    The Mw 7.9 Wenchuan earthquake of 12 May 2008 was the most destructive Chinese earthquake since the 1976 Tangshan event. Tens of thousands of people were killed, hundreds of thousands were injured, and millions were left homeless. Here we infer the detailed rupture process of the Wenchuan earthquake by back-projecting teleseismic P energy from several arrays of seismometers. This technique has only recently become feasible and is potentially faster than traditional finite-fault inversion of teleseismic body waves; therefore, it may reduce the notification time to emergency response agencies. Using the IRIS DMC, we collected 255 vertical component broadband P waves at 30-95° from the epicenter. We found that at periods of 5 s and greater, nearly all of these P waves were coherent enough to be used in a global array. We applied a simple down-sampling heuristic to define a global subarray of 70 stations that reduced the asymmetry and sidelobes of the array response function (ARF). We also considered three regional subarrays of seismometers in Alaska, Australia, and Europe that had apertures less than 30° and P waves that were coherent to periods as short as 1 s. Individual ARFs for these subarrays were skewed toward the subarrays; however, the linear sum of the regional subarray beams at 1 s produced a symmetric ARF, similar to that of the groomed global subarray at 5 s. For both configurations we obtained the same rupture direction, rupture length, and rupture time. We found that the Wenchuan earthquake had three distinct pulses of high beam power at 0, 23, and 57 s after the origin time, with the pulse at 23 s being highest, and that it ruptured unilaterally to the northeast for about 300 km and 110 s, with an average speed of 2.8 km/s. It is possible that similar results can be determined for future large dip-slip earthquakes within 20-30 min of the origin time using relatively sparse global networks of seismometers such as those the USGS uses to locate

  15. Rupture imaging of the Mw 7.9 12 May 2008 Wenchuan earthquake from back projection of teleseismic P waves

    Science.gov (United States)

    Xu, Y.; Koper, K.D.; Sufri, O.; Zhu, L.; Hutko, Alexander R.

    2009-01-01

    [1] The Mw 7.9 Wenchuan earthquake of 12 May 2008 was the most destructive Chinese earthquake since the 1976 Tangshan event. Tens of thousands of people were killed, hundreds of thousands were injured, and millions were left homeless. Here we infer the detailed rupture process of the Wenchuan earthquake by back-projecting teleseismic P energy from several arrays of seismometers. This technique has only recently become feasible and is potentially faster than traditional finite-fault inversion of teleseismic body waves; therefore, it may reduce the notification time to emergency response agencies. Using the IRIS DMC, we collected 255 vertical component broadband P waves at 30-95?? from the epicenter. We found that at periods of 5 s and greater, nearly all of these P waves were coherent enough to be used in a global array. We applied a simple down-sampling heuristic to define a global subarray of 70 stations that reduced the asymmetry and sidelobes of the array response function (ARF). We also considered three regional subarrays of seismometers in Alaska, Australia, and Europe that had apertures less than 30?? and P waves that were coherent to periods as short as 1 s. Individual ARFs for these subarrays were skewed toward the subarrays; however, the linear sum of the regional subarray beams at 1 s produced a symmetric ARF, similar to that of the groomed global subarray at 5 s. For both configurations we obtained the same rupture direction, rupture length, and rupture time. We found that the Wenchuan earthquake had three distinct pulses of high beam power at 0, 23, and 57 s after the origin time, with the pulse at 23 s being highest, and that it ruptured unilaterally to the northeast for about 300 km and 110 s, with an average speed of 2.8 km/s. It is possible that similar results can be determined for future large dip-slip earthquakes within 20-30 min of the origin time using relatively sparse global networks of seismometers such as those the USGS uses to locate

  16. Hepatic hydro thorax: patient with pleural effusion to the right presenting tracer migration to the contralateral thorax projection on early scintigraphic images

    International Nuclear Information System (INIS)

    Ichiki, W.A.; Ribeiro, V.P.B.; Gusman, L.; Coura Filho, G.B.; Sapienza, M.T.; Ono, C.R; Watanabe, T.; Costa, P.L.A.; Hironaka, F.; Cerri, G.G.; Buchpiguel, C.A.

    2008-01-01

    capacity are important factors to hepatic hydrothorax pathophysiology. Only the presence of pleural diaphragm fenestrations or imperfections may not be enough to explain the effusion, if the pleural absorptive capacity works to balance the fluid volume in the pleural space. Radiotracer migration to the contralateral thorax projection to the pleural effusion could be clarified in delayed complementary images, as in this case. Conclusion: The assessment of peritoneo-pleural shunt with radioisotopes is a useful methodology to confirm communication between peritoneum and pleura. The delayed complementary image after 24 hours of injection was important to the correct characterization of pleural effusion origin. (author)

  17. Evaluation of the RB-RB/LB-LB mnemonic rule for recording optimally projected intraoral images of dental implants: an in vitro study.

    Science.gov (United States)

    Schropp, L; Stavropoulos, A; Spin-Neto, R; Wenzel, A

    2012-05-01

    The aim of this study was to evaluate a simple mnemonic rule (the RB-RB/LB-LB rule) for recording intra-oral radiographs with optimal projection for the control of dental implants. 30 third-year dental students received a short lesson in the RB-RB/LB-LB mnemonic rule. The rule is as follows: if right blur then raise beam (RB-RB), i.e. if implant threads are blurred at the right side of the implant, the X-ray beam direction must be raised towards the ceiling to obtain sharp threads on both implant sides; if left blur then lower beam (LB-LB), i.e. if implant threads are blurred at the left side of the implant, the X-ray beam direction must be lowered towards the floor to obtain sharp threads on both implant sides. Intra-oral radiographs of four screw-type implants placed with different inclination in a Frasaco upper or lower jaw dental model (Frasaco GmbH, Tettnang, Germany) were recorded. The students were unaware of the inclination of the implants and were instructed to re-expose each implant, implementing the mnemonic rule, until an image of the implant with acceptable quality (subjectively judged by the instructor) was obtained. Subsequently, each radiograph was blindly assessed with respect to sharpness of the implant threads and assigned to one of four quality categories: (1) perfect, (2) not perfect, but clinically acceptable, (3) not acceptable and (4) hopeless. For all implants, from one non-perfect exposure to the following, a higher score was obtained in 64% of the cases, 28% received the same score and 8% obtained a lower score. Only a small variation was observed among exposures of implants with different inclination. On average, two exposures per implant (range: one to eight exposures) were needed to obtain a clinically acceptable image. The RB-RB/LB-LB mnemonic rule for recording intra-oral radiographs of dental implants with a correct projection was easy to implement by inexperienced examiners.

  18. The induced earthquake sequence related to the St. Gallen deep geothermal project (Switzerland): Fault reactivation and fluid interactions imaged by microseismicity

    Science.gov (United States)

    Diehl, T.; Kraft, T.; Kissling, E.; Wiemer, S.

    2017-09-01

    In July 2013, a sequence of more than 340 earthquakes was induced by reservoir stimulations and well-control procedures following a gas kick at a deep geothermal drilling project close to the city of St. Gallen, Switzerland. The sequence culminated in an ML 3.5 earthquake, which was felt within 10-15 km from the epicenter. High-quality earthquake locations and 3-D reflection seismic data acquired in the St. Gallen project provide a unique data set, which allows high-resolution studies of earthquake triggering related to the injection of fluids into macroscopic fault zones. In this study, we present a high-precision earthquake catalog of the induced sequence. Absolute locations are constrained by a coupled hypocenter-velocity inversion, and subsequent double-difference relocations image the geometry of the ML 3.5 rupture and resolve the spatiotemporal evolution of seismicity. A joint interpretation of earthquake and seismic data shows that the majority of the seismicity occurred in the pre-Mesozoic basement, hundreds of meters below the borehole and the targeted Mesozoic sequence. We propose a hydraulic connectivity between the reactivated fault and the borehole, likely through faults mapped by seismic data. Despite the excellent quality of the seismic data, the association of seismicity with mapped faults remains ambiguous. In summary, our results document that the actual hydraulic properties of a fault system and hydraulic connections between its fault segments are complex and may not be predictable upfront. Incomplete knowledge of fault structures and stress heterogeneities within highly complex fault systems additionally challenge the degree of predictability of induced seismicity related to underground fluid injections.

  19. Preliminary study of time maximum intensity projection computed tomography imaging for the detection of early ischemic change in patient with acute ischemic stroke.

    Science.gov (United States)

    Murayama, Kazuhiro; Suzuki, Shigetaka; Matsukiyo, Ryo; Takenaka, Akinori; Hayakawa, Motoharu; Tsutsumi, Takashi; Fujii, Kenji; Katada, Kazuhiro; Toyama, Hiroshi

    2018-03-01

    Noncontrast computed tomography (NCCT) has been used for the detection of early ischemic change (EIC); however, correct interpretation of NCCT findings requires much clinical experience. This study aimed to assess the accuracy of time maximum intensity projection computed tomography technique (tMIP), which reflects the maximum value for the time phase direction from the dynamic volume data for each projected plane, for detection of EIC, against that of NCCT.Retrospective review of NCCT, cerebral blood volume in CT perfusion (CTP-CBV), and tMIP of 186 lesions from 280 regions evaluated by Alberta Stroke Program Early CT Score (ASPECTS) in 14 patients with acute middle cerebral artery stroke who had undergone whole-brain CTP using 320-row area detector CT was performed. Four radiologists reviewed EIC on NCCT, CTP-CBV, and tMIP in each ASPECTS region at onset using the continuous certainty factor method. Receiver operating characteristic analysis was performed to compare the relative performance for detection of EIC. The correlations were evaluated.tMIP-color showed the best discriminative value for detection of EIC. There were significant differences in the area under the curve for NCCT and tMIP-color, CTP-CBV (P < .05). Scatter plots of ASPECTS showed a positive significant correlation between NCCT, tMIP-gray, tMIP-color, and the follow-up study (NCCT, r = 0.32, P = .0166; tMIP-gray, r = 0.44, P = .0007; tMIP-color, r = 0.34, P = .0104).Because tMIP provides a high contrast parenchymal image with anatomical and vascular information in 1 sequential scan, it showed greater accuracy for detection of EIC and predicted the final infarct extent more accurately than NCCT based on ASPECTS.

  20. Solar ENA Imaging Coronagraph Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Measurements of energetic neutral atoms (ENAs) are a new tool to improve our understanding of energy release and particle acceleration in solar eruptive events....

  1. Cardiac Imager Project Mechanical Design

    CERN Document Server

    Pepato, Adriano

    2000-01-01

    La nota riporta i criteri principali di progetto di una camera proporzionale a multianodi a filo, sviluppata per la scintigrafia del cuore, nell¹ambito di un progetto finanziato dalla Comunità Europea. I rivelatori ad alto counting rate risultano di grande interesse nell¹ambito della medicina nucleare, perchè garantiscono immagini dinamiche ad alta risoluzione statistica, pur a fronte di una consistente riduzione dell¹intensità della dose radiogena minima e del conseguente tempo di esposizione. E¹ stata svilupppata quindi una gamma camera ad elevata velocità riempita di una miscela di Xenon gas ultrapuro ed Etano; il sistema è utilizzato ad una pressione di esercizio compresa tra i 5 ed 10 bar abs. La superficie attiva è di $250x250 mm^{2}$. Al fine di garantire condizioni di esercizio stabili per tempi lunghi, senza degradazione dell¹efficienza, è stato progettato un sistema di purificazione in continua del gas, integrato a bordo del rivelatore. E¹ stato realizzato un prototipo funzionante da or...

  2. SU-C-18C-02: Specifcation of X-Ray Projection Angles Which Are Aligned with the Aortic Valve Plane From a Planar Image of a Valvuloplasty Balloon Inflated Across the Aortic Valve

    International Nuclear Information System (INIS)

    Fetterly, K; Mathew, V

    2014-01-01

    Purpose: Transcatheter aortic valve replacement (TAVR) procedures provide a method to implant a prosthetic aortic valve via a minimallyinvasive, catheter-based procedure. TAVR procedures require use of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane to minimize prosthetic valve positioning error due to x-ray imaging parallax. The purpose of this work is to calculate the continuous range of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane from a single planar image of a valvuloplasty balloon inflated across the aortic valve. Methods: Computational methods to measure the 3D angular orientation of the aortic valve were developed. Required inputs include a planar x-ray image of a known valvuloplasty balloon inflated across the aortic valve and specifications of x-ray imaging geometry from the DICOM header of the image. A-priori knowledge of the species-specific typical range of aortic orientation is required to specify the sign of the angle of the long axis of the balloon with respect to the x-ray beam. The methods were validated ex-vivo and in a live pig. Results: Ex-vivo experiments demonstrated that the angular orientation of a stationary inflated valvuloplasty balloon can be measured with precision less than 1 degree. In-vivo pig experiments demonstrated that cardiac motion contributed to measurement variability, with precision less than 3 degrees. Error in specification of x-ray geometry directly influences measurement accuracy. Conclusion: This work demonstrates that the 3D angular orientation of the aortic valve can be calculated precisely from a planar image of a valvuloplasty balloon inflated across the aortic valve and known x-ray geometry. This method could be used to determine appropriate c-arm angular projections during TAVR procedures to minimize x-ray imaging parallax and thereby minimize prosthetic valve positioning errors

  3. SU-C-18C-02: Specifcation of X-Ray Projection Angles Which Are Aligned with the Aortic Valve Plane From a Planar Image of a Valvuloplasty Balloon Inflated Across the Aortic Valve

    Energy Technology Data Exchange (ETDEWEB)

    Fetterly, K; Mathew, V [Mayo Clinic, Rochester, MN (United States)

    2014-06-01

    Purpose: Transcatheter aortic valve replacement (TAVR) procedures provide a method to implant a prosthetic aortic valve via a minimallyinvasive, catheter-based procedure. TAVR procedures require use of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane to minimize prosthetic valve positioning error due to x-ray imaging parallax. The purpose of this work is to calculate the continuous range of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane from a single planar image of a valvuloplasty balloon inflated across the aortic valve. Methods: Computational methods to measure the 3D angular orientation of the aortic valve were developed. Required inputs include a planar x-ray image of a known valvuloplasty balloon inflated across the aortic valve and specifications of x-ray imaging geometry from the DICOM header of the image. A-priori knowledge of the species-specific typical range of aortic orientation is required to specify the sign of the angle of the long axis of the balloon with respect to the x-ray beam. The methods were validated ex-vivo and in a live pig. Results: Ex-vivo experiments demonstrated that the angular orientation of a stationary inflated valvuloplasty balloon can be measured with precision less than 1 degree. In-vivo pig experiments demonstrated that cardiac motion contributed to measurement variability, with precision less than 3 degrees. Error in specification of x-ray geometry directly influences measurement accuracy. Conclusion: This work demonstrates that the 3D angular orientation of the aortic valve can be calculated precisely from a planar image of a valvuloplasty balloon inflated across the aortic valve and known x-ray geometry. This method could be used to determine appropriate c-arm angular projections during TAVR procedures to minimize x-ray imaging parallax and thereby minimize prosthetic valve positioning errors.

  4. 99mTc labelled peptides for imaging of peripheral receptors. Final report of a co-ordinated research project. 1995-1999

    International Nuclear Information System (INIS)

    2001-04-01

    99m Tc radiopharmaceuticals have remained the workhorse of diagnostic nuclear medicine over the last three decades ever since the introduction of the gamma camera as the main imaging instrument. Due to the near ideal nuclear properties such as gamma energy, half-life, lack of beta radiation and easy availability as a convenient generator system at an affordable cost of 99m Tc, it can be reasonably anticipated that 99m Tc will continue to retain this position in the foreseeable future. To a large extent this has been possible because of the successful development, over the years, of 99m Tc radiopharmaceuticals as substitutes for other clinically well established agents. Examples of these success stories are 99m Tc substitutes for 131 I hippuran and rose bengal 201 Tl and 123 I brain perfusion agents, which have come to be known collectively as 'second generation 99m Tc radiopharmaceuticals'. It should be acknowledged that each one of these developments was a result of innovative and sustained research and development efforts by scientists from different parts of the world. Concurrently these research efforts have made significant contributions to better understanding of the radiochemistry and co-ordination chemistry of 99m Tc. The radiopharmaceutical scientists are now in a much better position to design, prepare and evaluate 99m Tc complexes for specific applications. Building on this capability, the next step is development of 99m Tc substitutes for receptor specific radiopharmaceuticals, which have established clinical potential. Efforts in this direction are already ongoing and the work during the last decade on 99m Tc labelling of monoclonal antibodies can be considered the beginning of these 'third generation 99m Tc radiopharmaceuticals'. The International Atomic Energy Agency (IAEA) had organized two co-ordinated research projects (CRPs) in the past covering 99m Tc second generation agents and 99m Tc monoclonal antibodies, and the results were published in

  5. The Seismogenic Coupling Zone in Southern Central Chile, 38° S: A Reflection seismic image of the subduction zone (Project TIPTEQ)

    Science.gov (United States)

    Schulze, A.; Micksch, U.; Krawczyk, C. M.; Ryberg, T.; Stiller, M.

    2006-12-01

    The multi-disciplinary project TIPTEQ (from The Incoming Plate to mega-Thrust EarthQuake processes) investigates the seismogenic coupling zone in Southern Central Chile and the associated subduction zone processes between the Pacific Ocean and the volcanic arc. The reflection seismic component of TIPTEQ includes a 110 km long profile which spans from the coast over the down-dip end of the seismogenic coupling zone, crossing the 1960 Valdivia earthquake hypocentre. 180 three-component geophones were deployed (100 m spacing) along an 18 km wide spread whereof 4.5 km were shifted in a daily roll-along. With 100 borehole shots, 1.5 km apart, this up to 8-fold covered line delivers a high-resolution image of the seismogenic coupling zone. 15 additional shots in an expanding spread profiling configuration focussed on the seismogenic coupling zone. SH wave source signals were generated to yield an improved picture of the petrophysical contrasts within the system. The SPOC-South wide-angle data velocity model is combined with a first-break tomography velocity model to get an advanced migration image. The subducting Nazca plate can be traced from a depth of 25 km below the coast down to a depth of 50 km at the eastern end of the profile. Structural evidence suggests that material is transported down in a subduction channel. From slow uplift of the Coastal Cordillera we conclude that basal accretion of parts of this material controls the seismic architecture and growth of the south Chilean crust. Between depths of 5 to 25 km several bright reflectivity spots can be seen in the upper plate, which may suggest fluid traps in the accretionary wedge. The tomographic p-wave velocity model reaches approximately 10 km depth. Its segmentation corresponds to the geological units mapped at surface. The sediment thickness in the Central Valley is approx. 3 km, and we see prominent fault systems like the Lanalhue fault zone also in the tomographic model. At present, almost no seismicity

  6. A novel approach to imaging extinct seafloor massive sulphides (eSMS) by using ocean bottom seismometer data from the Blue Mining project

    Science.gov (United States)

    Gil, A.; Chidlow, K. L.; Vardy, M. E.; Bialas, J.; Schroeder, H.; Stobbs, I. J.; Gehrmann, R. A. S.; North, L. J.; Minshull, T. A.; Petersen, S.; Murton, B. J.

    2017-12-01

    Seafloor massive sulphide (SMS) deposits have generated great interest regarding their formation and composition, since their discovery in 1977. SMS deposits form through hydrothermal circulation and are therefore commonly found near hydrothermal vent sites. The high base (Cu, Zn) and precious metal (Au, Ag) content has interested mining companies, due to their potentially high economic value. Currently, the possibility of mining extinct seafloor massive sulphides (eSMS) deposits has opened a debate about their environmentally and economically sustainable exploitation. A major goal is the rapid exploration and assessment of deposit structure and volume. This is challenging due to their small dimensions (100s m diameter) and typically great water depths (> 3000 mbsl). Here we present a novel approach combining seismic reflection/refraction forward modelling to data acquired from the TAG hydrothermal field (26ºN, Mid-Atlantic Ridge, 3500mbsl) to image deep-water eSMS deposits. In May 2016, the RV METEOR shot 30, short (<10km) MSC profiles across the TAG area. The data were recorded on a dense cluster (<75 m apart) of ocean bottom seismometers (OBS) and were able to image the subsurface of several 300m diameter eSMS deposits. The results show that the eSMS deposits present high velocities (5.4-6.6 km/s) to depths 200m below the seafloor where they are hosted in a 500m thick low-velocity (3.0-3.7 km/s) layer of altered basalt. In contrast to active hydrothermal systems, we see no evidence in the eSMS of a low-velocity anhydrite layer. The velocity-depth models obtained from this innovative method have been combined with other methods to study these eSMS deposits, such as electromagnetics, rocks physics and drilling technics, and the results are shown to concur, yielding information about deposit structure at depth. For example, the high-velocity layer extends deeper than the conductive layer, indicating a deep stock work of low-connectivity sulphides beneath a main

  7. Investigation of the 27 February 2010 Mw 8.8 Chilean earthquake integrating aftershock analysis, back-projection imaging and cGPS results

    Science.gov (United States)

    Clévédé, E.; Satriano, C.; Bukchin, B.; Lancieri, M.; Fuenzalida, A.; Vilotte, J.; Lyon-Caen, H.; Vigny, C.; Socquet, A.; Aranda, C.; Campos, J. A.; Scientific Team of the Lia Montessus de Ballore (Cnrs-Insu, U. Chile)

    2010-12-01

    The Mw 8.8 earthquake in central Chile ruptured more than 400 km along the subduction bound between the Nazca and the South American plates. The aftershock distribution clearly shows that this earthquake filled a well-known seismic gap, corresponding to rupture extension of the 1835 earthquake. The triggered post-seismic activity extends farther north of the gap, partially overlapping the 1985 and the 1960 Valparaiso earthquakes. However, the analysis of continuous GPS (cGPS) recordings, and back projection imaging of teleseismic body wave energy, indicate that the rupture stopped south of Valparaiso, around -33.5 degrees of latitude. An important question is how far the rupture actually extended to the north and the potential relation between the northernmost aftershock activity and remaining asperities within the ruptured zone of the previous Valparaiso earthquakes. The extension of the rupture offshore, towards west, also deserves further investigation. The aftershock distribution and the back propagation analysis support the hypothesis that, in the northern part, the rupture may have reached the surface at the trench. In this work, we performed a CMT and depth location study for more than 10 of the immediate largest aftershocks using teleseismic surface wave analysis constrained by P-wave polarity. In parallel, a detailed analysis of aftershocks in the northern part of the rupture, between 2010-03-11 and 2010-05-13, have been performed using the data from the station of the Chilean Servicio Sismológico Nacional (SSN), and of the post-seismic network, deployed by the French CNRS-INSU, GFZ, IRIS, and Caltech. We accurately hand-picked 153 larger events, which have been located using a non-linear probabilistic code, with improved depth location. Focal mechanisms have been computed for the larger events. Those results have been integrated with the analysis of cGPS and teleseismic back projection, and the overall kinematic of the Maule earthquake is discussed as

  8. Comparison of image quality and visibility of normal and abnormal findings at submillisievert chest CT using filtered back projection, iterative model reconstruction (IMR) and iDose{sup 4}™

    Energy Technology Data Exchange (ETDEWEB)

    Laqmani, Azien, E-mail: a.laqmani@uke.de [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Avanesov, Maxim; Butscheidt, Sebastian; Kurfürst, Maximilian [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Sehner, Susanne [Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Schmidt-Holtz, Jakob; Derlin, Thorsten; Behzadi, Cyrus [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Nagel, Hans D. [Science & Technology for Radiology, Fritz-Reuter-Weg 5f, 21244 Buchholz, Germany, (Germany); Adam, Gerhard; Regier, Marc [Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

    2016-11-15

    Objective: To compare both image quality and visibility of normal and abnormal findings at submillisievert chest CT (smSv-CT) using filtered back projection (FBP) and the two different iterative reconstruction (IR) techniques iterative model reconstruction (IMR) and iDose{sup 4}™. Materials and methods: This institutional review board approved study was based on retrospective interpretation of clinically indicated acquired data. The requirement to obtain informed consent was waived. 81 patients with suspected pneumonia underwent smSv-CT (Brilliance iCT, Philips Healthcare; mean effective dose: 0.86 ± 0.2 mSv). Data were reconstructed using FBP and two different IR techniques iDose{sup 4}™ and IMR (Philips Healthcare) at various iteration levels. Objective image noise (OIN) was measured. Two experienced readers independently assessed all images for image noise, image appearance and visibility of normal anatomic and abnormal findings. A random intercept model was used for statistical analysis. Results: Compared to FBP and iDose{sup 4}™, IMR reduced OIN up to 88% and 72%, respectively (p < 0.001). A mild blotchy image appearance was seen in IMR images, affecting diagnostic confidence. iDose{sup 4}™ images provided satisfactory to good image quality for visibility of normal and abnormal findings and were superior to FBP (p < 0.001). IMR images were significantly inferior for visibility of normal structures compared to iDose{sup 4}™, while being superior for visibility of abnormal findings except for reticular pattern (p < 0.001). Conclusion: IMR results for visibility of normal and abnormal lung findings are heterogeneous, indicating that IMR may not represent a priority technique for clinical routine. iDose{sup 4}™ represents a suitable method for evaluation of lung tissue at submillisievert chest CT.

  9. Comparison of image quality and visibility of normal and abnormal findings at submillisievert chest CT using filtered back projection, iterative model reconstruction (IMR) and iDose4™.

    Science.gov (United States)

    Laqmani, Azien; Avanesov, Maxim; Butscheidt, Sebastian; Kurfürst, Maximilian; Sehner, Susanne; Schmidt-Holtz, Jakob; Derlin, Thorsten; Behzadi, Cyrus; Nagel, Hans D; Adam, Gerhard; Regier, Marc

    2016-11-01

    To compare both image quality and visibility of normal and abnormal findings at submillisievert chest CT (smSv-CT) using filtered back projection (FBP) and the two different iterative reconstruction (IR) techniques iterative model reconstruction (IMR) and iDose 4 ™. This institutional review board approved study was based on retrospective interpretation of clinically indicated acquired data. The requirement to obtain informed consent was waived. 81 patients with suspected pneumonia underwent smSv-CT (Brilliance iCT, Philips Healthcare; mean effective dose: 0.86±0.2mSv). Data were reconstructed using FBP and two different IR techniques iDose 4 ™ and IMR (Philips Healthcare) at various iteration levels. Objective image noise (OIN) was measured. Two experienced readers independently assessed all images for image noise, image appearance and visibility of normal anatomic and abnormal findings. A random intercept model was used for statistical analysis. Compared to FBP and iDose 4 ™, IMR reduced OIN up to 88% and 72%, respectively (p<0.001). A mild blotchy image appearance was seen in IMR images, affecting diagnostic confidence. iDose 4 ™ images provided satisfactory to good image quality for visibility of normal and abnormal findings and were superior to FBP (p<0.001). IMR images were significantly inferior for visibility of normal structures compared to iDose 4 ™, while being superior for visibility of abnormal findings except for reticular pattern (p<0.001). IMR results for visibility of normal and abnormal lung findings are heterogeneous, indicating that IMR may not represent a priority technique for clinical routine. iDose 4 ™ represents a suitable method for evaluation of lung tissue at submillisievert chest CT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Image, Image, Image

    Science.gov (United States)

    Howell, Robert T.

    2004-01-01

    With all the talk today about accountability, budget cuts, and the closing of programs in public education, teachers cannot overlook the importance of image in the field of industrial technology. It is very easy for administrators to cut ITE (industrial technology education) programs to save school money--money they might shift to teaching the…

  11. IMAGES, IMAGES, IMAGES

    Energy Technology Data Exchange (ETDEWEB)

    Marcus, A.

    1980-07-01

    The role of images of information (charts, diagrams, maps, and symbols) for effective presentation of facts and concepts is expanding dramatically because of advances in computer graphics technology, increasingly hetero-lingual, hetero-cultural world target populations of information providers, the urgent need to convey more efficiently vast amounts of information, the broadening population of (non-expert) computer users, the decrease of available time for reading texts and for decision making, and the general level of literacy. A coalition of visual performance experts, human engineering specialists, computer scientists, and graphic designers/artists is required to resolve human factors aspects of images of information. The need for, nature of, and benefits of interdisciplinary effort are discussed. The results of an interdisciplinary collaboration are demonstrated in a product for visualizing complex information about global energy interdependence. An invited panel will respond to the presentation.

  12. Time-Encoded Imagers.

    Energy Technology Data Exchange (ETDEWEB)

    Marleau, Peter; Brubaker, Erik

    2014-11-01

    This report provides a short overview of the DNN R&D funded project, Time-Encoded Imagers. The project began in FY11 and concluded in FY14. The Project Description below provides the overall motivation and objectives for the project as well as a summary of programmatic direction. It is followed by a short description of each task and the resulting deliverables.

  13. A Novel Passive Millimeter Imager for Broad-Area Search - Final Report on Project PL09-NPMI-PD07 (PNNL-55180)

    Energy Technology Data Exchange (ETDEWEB)

    Tedeschi, Jonathan R.; Bernacki, Bruce E.; Kelly, James F.; Sheen, David M.; Harris, Robert V.; Hall, Thomas E.; Hatchell, Brian K.; Knopik, Clint D.; Lechelt, Wayne M.; McMakin, Douglas L.; Mendoza, Albert; Severtsen, Ronald H.; Valdez, Patrick LJ

    2011-12-31

    This report describes research and development efforts toward a novel passive millimeter-wave (mm-wave) electromagnetic imaging device for broad-area search. It addresses the technical challenge of detecting anomalies that occupy a small fraction of a pixel. The purpose of the imager is to pinpoint suspicious locations for cuing subsequent higher-resolution imaging. The technical basis for the approach is to exploit thermal and polarization anomalies that distinguish man-made features from natural features.

  14. Medical imaging technology

    CERN Document Server

    Haidekker, Mark A

    2013-01-01

    Biomedical imaging is a relatively young discipline that started with Conrad Wilhelm Roentgen’s discovery of the x-ray in 1885. X-ray imaging was rapidly adopted in hospitals around the world. However, it was the advent of computerized data and image processing that made revolutionary new imaging modalities possible. Today, cross-sections and three-dimensional reconstructions of the organs inside the human body is possible with unprecedented speed, detail and quality. This book provides an introduction into the principles of image formation of key medical imaging modalities: X-ray projection imaging, x-ray computed tomography, magnetic resonance imaging, ultrasound imaging, and radionuclide imaging. Recent developments in optical imaging are also covered. For each imaging modality, the introduction into the physical principles and sources of contrast is provided, followed by the methods of image formation, engineering aspects of the imaging devices, and a discussion of strengths and limitations of the modal...

  15. Radiology Architecture Project Primer.

    Science.gov (United States)

    Sze, Raymond W; Hogan, Laurie; Teshima, Satoshi; Davidson, Scott

    2017-12-19

    The rapid pace of technologic advancement and increasing expectations for patient- and family-friendly environments make it common for radiology leaders to be involved in imaging remodel and construction projects. Most radiologists and business directors lack formal training in architectural and construction processes but are expected to play significant and often leading roles in all phases of an imaging construction project. Avoidable mistakes can result in significant increased costs and scheduling delays; knowledgeable participation and communication can result in a final product that enhances staff workflow and morale and improves patient care and experience. This article presents practical guidelines for preparing for and leading a new imaging architectural and construction project. We share principles derived from the radiology and nonradiology literature and our own experience over the past decade completely remodeling a large pediatric radiology department and building a full-service outpatient imaging center. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  16. Preliminary images from an adaptive imaging system

    NARCIS (Netherlands)

    Griffiths, J.A.; Metaxas, M.G.; Pani, S.; Schulerud, H.; Esbrand, C.; Royle, G.J.; Price, B.; Rokvic, T.; Longo, R.; Asimidis, A.; Bletsas, E.; Cavouras, D.; Fant, A.; Gasiorek, P.; Georgiou, H.; Hall, G.; Jones, J.; Leaver, J.; Li, G.; Machin, D.; Manthos, N.; Matheson, J.; Noy, M.; Østby, J.M.; Psomadellis, F.; van der Stelt, P.F.; Theodoridis, S.; Triantis, F.; Turchetta, R.; Venanzi, C.; Speller, R.D.

    2008-01-01

    I-ImaS (Intelligent Imaging Sensors) is a European project aiming to produce real-time adaptive X-ray imaging systems using Monolithic Active Pixel Sensors (MAPS) to create images with maximum diagnostic information within given dose constraints. Initial systems concentrate on mammography and

  17. ENVISION Project

    CERN Multimedia

    Ballantine, A; Dixon-Altaber, H; Dosanjh, M; Kuchina, L

    2011-01-01

    Hadrontherapy is a highly advanced technique of cancer radiotherapy that uses beams of charged particles (ions) to destroy tumour cells. While conventional X-rays traverse the human body depositing radiation as they pass through, ions deliver most of their energy at one point. Hadrontherapy is most advantageous once the position of the tumour is accurately known, so that healthy tissues can be protected. Accurate positioning is a crucial challenge for targeting moving organs, as in lung cancer, and for adapting the irradiation as the tumour shrinks with treatment. Therefore, quality assurance becomes one of the most relevant issues for an effective outcome of the cancer treatment. In order to improve the quality assurance tools for hadrontherapy, the European Commission is funding ENVISION, a 4-year project that aims at developing solutions for: real-• time non invasive monitoring • quantitative imaging • precise determination of delivered dose • fast feedback for optimal treatment planning • real-t...

  18. Optimization of the radiological protection of patients: Image quality and dose in mammography (co-ordinated research in Europe). Results of the coordinated research project on optimization of protection mammography in some eastern European States

    International Nuclear Information System (INIS)

    2005-05-01

    Mammography is an extremely useful non-invasive imaging technique with unparalleled advantages for the detection of breast cancer. It has played an immense role in the screening of women above a certain age or with a family history of breast cancer. The IAEA has a statutory responsibility to establish standards for the protection of people against exposure to ionizing radiation and to provide for the worldwide application of those standards. A fundamental requirement of the International Basic Safety Standards for Protection Against Ionizing Radiation (BSS) and for the Safety of Radiation Sources, issued by the IAEA and co-sponsored by FAO, ILO, WHO, PAHO and NEA, is the optimization of radiological protection of patients undergoing medical exposure. In keeping with its responsibility on the application of standards, the IAEA programme on Radiological Protection of Patients attempts to reduce radiation doses to patients while balancing quality assurance considerations. IAEA-TECDOC-796, Radiation Doses in Diagnostic Radiology and Methods for Dose Reduction (1995), addresses this aspect. The related IAEA-TECDOC-1423 on Optimization of the Radiological Protection of Patients undergoing Radiography, Fluoroscopy and Computed Tomography, (2004) constitutes the final report of the coordinated research in Africa, Asia and eastern Europe. The preceding publications do not explicitly consider mammography. Mindful of the importance of this imaging technique, the IAEA launched a Coordinated Research Project on Optimization of Protection in Mammography in some eastern European States. The present publication is the outcome of this project: it is aimed at evaluating the situation in a number of countries, identifying variations in the technique, examining the status of the equipment and comparing performance in the light of the norms established by the European Commission. A number of important aspects are covered, including: - quality control of mammography equipment; - imaging

  19. Medical imaging

    CERN Document Server

    Townsend, David W

    1996-01-01

    Since the introduction of the X-ray scanner into radiology almost 25 years ago, non-invasive imaging has become firmly established as an essential tool in the diagnosis of disease. Fully three-dimensional imaging of internal organs is now possible, b and for studies which explore the functional status of the body. Powerful techniques to correlate anatomy and function are available, and scanners which combine anatomical and functional imaging in a single device are under development. Such techniques have been made possible through r ecent technological and mathematical advances. This series of lectures will review both the physical basis of medical imaging techniques using X-rays, gamma and positron emitting radiosiotopes, and nuclear magnetic resonance, and the mathematical methods used to reconstruct three-dimentional distributions from projection data. The lectures will trace the development of medical imaging from simple radiographs to the present-day non-invasive measurement of in vivo biochemistry. They ...

  20. Computed tomography of the cervical spine: comparison of image quality between a standard-dose and a low-dose protocol using filtered back-projection and iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Becce, Fabio [University of Lausanne, Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Universite Catholique Louvain, Department of Radiology, Cliniques Universitaires Saint-Luc, Brussels (Belgium); Ben Salah, Yosr; Berg, Bruno C. vande; Lecouvet, Frederic E.; Omoumi, Patrick [Universite Catholique Louvain, Department of Radiology, Cliniques Universitaires Saint-Luc, Brussels (Belgium); Verdun, Francis R. [University of Lausanne, Institute of Radiation Physics, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Meuli, Reto [University of Lausanne, Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland)

    2013-07-15

    To compare image quality of a standard-dose (SD) and a low-dose (LD) cervical spine CT protocol using filtered back-projection (FBP) and iterative reconstruction (IR). Forty patients investigated by cervical spine CT were prospectively randomised into two groups: SD (120 kVp, 275 mAs) and LD (120 kVp, 150 mAs), both applying automatic tube current modulation. Data were reconstructed using both FBP and sinogram-affirmed IR. Image noise, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were measured. Two radiologists independently and blindly assessed the following anatomical structures at C3-C4 and C6-C7 levels, using a four-point scale: intervertebral disc, content of neural foramina and dural sac, ligaments, soft tissues and vertebrae. They subsequently rated overall image quality using a ten-point scale. For both protocols and at each disc level, IR significantly decreased image noise and increased SNR and CNR, compared with FBP. SNR and CNR were statistically equivalent in LD-IR and SD-FBP protocols. Regardless of the dose and disc level, the qualitative scores with IR compared with FBP, and with LD-IR compared with SD-FBP, were significantly higher or not statistically different for intervertebral discs, neural foramina and ligaments, while significantly lower or not statistically different for soft tissues and vertebrae. The overall image quality scores were significantly higher with IR compared with FBP, and with LD-IR compared with SD-FBP. LD-IR cervical spine CT provides better image quality for intervertebral discs, neural foramina and ligaments, and worse image quality for soft tissues and vertebrae, compared with SD-FBP, while reducing radiation dose by approximately 40 %. (orig.)

  1. NOAA TIFF Image - 1 m Backscatter Mosaic of the St. John Shelf, U.S. Virgin Islands, Project NF-10-03, 2010, UTM 20 WGS84

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the St. John Shelf, US Virgin Islands. NOAA's NOS/NCCOS/CCMA Biogeography Team, in collaboration...

  2. NOAA TIFF Image - 3 m Backscatter Mosaic of the south west shore (La Parguera) of Puerto Rico, Project NF-06-03, 2006, UTM 19 WGS84

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 3 meter resolution backscatter mosaic of the south west shore (La Parguera) of Puerto Rico. NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  3. NOAA TIFF Image - 1 m Backscatter Mosaic of Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD83 (NCEI Accession 0131853)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of Bajo de Cico off the coast of western Puerto Rico, collected using a Kongsberg EM 1002 (95 kHz)...

  4. NOAA TIFF Image- 0.5 meter Backscatter Mosaic of Grammanik Bank - East (St. Thomas), US Virgin Islands, Project NF-05-05, 2005, UTM 20 NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.5 meter resolution backscatter mosaic of Grammanik Bank, south of St. Thomas, US Virgin Islands.NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  5. NOAA TIFF Image- 0.5 meter Backscatter Mosaic of Mid Shelf Reef (St. Thomas), US Virgin Islands, Project NF-05-05, 2005, UTM 20 NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.5 meter resolution backscatter mosaic of the Mid Shelf Reef south of St. Thomas, US Virgin IslandsNOAA's NOS/NCCOS/CCMA Biogeography Team,...

  6. NOAA TIFF Image - 2 m Backscatter Mosaic of Isla de Mona, PR, Project NF-07-06, 2007, UTM 19 NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 2 meter resolution backscatter mosaic of the southern coast of Isla de Mona, collected using a Kongsberg EM 1002 (95 kHz) multibeam...

  7. NOS TIFF Image, 3M Backscatter Mosaic La Parguera, Puerto Rico, 2006 : Project NF-06-03, UTM 19 NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 3 meter resolution backscatter mosaic of the south west shore (La Parguera) of Puerto Rico. NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  8. NOAA TIFF Image - 2 m Backscatter Mosaic of Isla de Mona, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD83 (NCEI Accession 0131853)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 2 meter resolution backscatter mosaic of the southern coast of Isla de Mona, collected using a Kongsberg EM 1002 (95 kHz) multibeam...

  9. Validation and Sensitivity Analysis of 3D Synthetic Aperture Radar (SAR) Imaging of the Interior of Primitive Solar System Bodies: Comets and Asteroids Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To probe the interior of a comet, we are going to employ Radar Reflection Imager (RRI) Instrument on an orbiting platform. While orbiting around the comet at a safe...

  10. HUMN project initiative and review of validation, quality control and prospects for further development of automated micronucleus assays using image cytometry systems

    Czech Academy of Sciences Publication Activity Database

    Fenech, M.; Kirsch-Volders, M.; Rössnerová, Andrea; Šrám, Radim; Romm, H.; Bolognesi, C.; Ramakumar, A.; Soussaline, F.; Schunck, CH.; Elhajouji, A.; Anwar, W.; Bonassi, S.

    2013-01-01

    Roč. 216, č. 5 (2013), s. 541-552 ISSN 1438-4639 R&D Projects: GA ČR GAP503/11/0084 Grant - others:Project NewGenesis(XE) FOOD-CT-2005-016320 Institutional support: RVO:68378041 Keywords : Micronucleus * Cytokinesis-block * Automation Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.276, year: 2013

  11. scikit-image: image processing in Python

    Directory of Open Access Journals (Sweden)

    Stéfan van der Walt

    2014-06-01

    Full Text Available scikit-image is an image processing library that implements algorithms and utilities for use in research, education and industry applications. It is released under the liberal Modified BSD open source license, provides a well-documented API in the Python programming language, and is developed by an active, international team of collaborators. In this paper we highlight the advantages of open source to achieve the goals of the scikit-image library, and we showcase several real-world image processing applications that use scikit-image. More information can be found on the project homepage, http://scikit-image.org.

  12. scikit-image: image processing in Python.

    Science.gov (United States)

    van der Walt, Stéfan; Schönberger, Johannes L; Nunez-Iglesias, Juan; Boulogne, François; Warner, Joshua D; Yager, Neil; Gouillart, Emmanuelle; Yu, Tony

    2014-01-01

    scikit-image is an image processing library that implements algorithms and utilities for use in research, education and industry applications. It is released under the liberal Modified BSD open source license, provides a well-documented API in the Python programming language, and is developed by an active, international team of collaborators. In this paper we highlight the advantages of open source to achieve the goals of the scikit-image library, and we showcase several real-world image processing applications that use scikit-image. More information can be found on the project homepage, http://scikit-image.org.

  13. HBCU/MI: 3D Formable RF Materials and Devices

    Science.gov (United States)

    2016-08-01

    Page 15 of 15 Pioneering 21st Century Electromagnetics and Photonics [2] "DuPont CB028 Silver Conductor . Technical Data Sheet," DuPont, Ed., ed, 2013...R. A. Street, "Thermal cure effects on electrical performance of nanoparticle silver inks," Acta Materialia, vol. 55, pp. 6345-6349, 10// 2007. [6...Awarded Awards Graduate Students Schellenger Professorship in Electrical Engineering, 2015 Star on the Mountain Award, City of El Paso, 2015 2015

  14. Impact of model-based iterative reconstruction on low-contrast lesion detection and image quality in abdominal CT: a 12-reader-based comparative phantom study with filtered back projection at different tube voltages

    Energy Technology Data Exchange (ETDEWEB)

    Euler, Andre; Stieltjes, Bram; Eichenberger, Reto; Reisinger, Clemens; Hirschmann, Anna; Zaehringer, Caroline; Kircher, Achim; Streif, Matthias; Bucher, Sabine; Buergler, David; D' Errico, Luigia; Kopp, Sebastien; Wilhelm, Markus [University Hospital Basel, Clinic of Radiology and Nuclear Medicine, Basel (Switzerland); Szucs-Farkas, Zsolt [Hospital Centre of Biel, Institute of Radiology, Biel (Switzerland); Schindera, Sebastian T. [University Hospital Basel, Clinic of Radiology and Nuclear Medicine, Basel (Switzerland); Cantonal Hospital Aarau, Institute of Radiology, Aarau (Switzerland)

    2017-12-15

    To evaluate the impact of model-based iterative reconstruction (MBIR) on image quality and low-contrast lesion detection compared with filtered back projection (FBP) in abdominal computed tomography (CT) of simulated medium and large patients at different tube voltages. A phantom with 45 hypoattenuating lesions was placed in two water containers and scanned at 70, 80, 100, and 120 kVp. The 120-kVp protocol served as reference, and the volume CT dose index (CTDI{sub vol}) was kept constant for all protocols. The datasets were reconstructed with MBIR and FBP. Image noise and contrast-to-noise-ratio (CNR) were assessed. Low-contrast lesion detectability was evaluated by 12 radiologists. MBIR decreased the image noise by 24% and 27%, and increased the CNR by 30% and 29% for the medium and large phantoms, respectively. Lower tube voltages increased the CNR by 58%, 46%, and 16% at 70, 80, and 100 kVp, respectively, compared with 120 kVp in the medium phantom and by 9%, 18% and 12% in the large phantom. No significant difference in lesion detection rate was observed (medium: 79-82%; large: 57-65%; P > 0.37). Although MBIR improved quantitative image quality compared with FBP, it did not result in increased low-contrast lesion detection in abdominal CT at different tube voltages in simulated medium and large patients. (orig.)

  15. Filmless radiology: The design, integration, implementation, and evaluation of a digital imaging network. Potential investigations to be conducted in conjunction with the Digital-Imaging Network System (DINS) evaluation project. Revision 1. Annual report, 1 March 1987-28 February 1988

    Energy Technology Data Exchange (ETDEWEB)

    Kerlin, B.D.; Cerva, J.R.; Glenn, M.E.; Harrington, M.B.; Nadel, L.D.

    1988-06-01

    This document describes evaluation studies and technical investigations proposed for the three-year Digital Imaging Network System (DINS) prototype project, sponsored by the U.S. Army Medical Research and Development Command, Ft. Detrick, Maryland. The project has three overall goals. The first is to install and operate a prototype DINS at each of two University-based hospitals for test purposes. The second is to evaluate key aspects of each prototype system once it is in full operation. The third is to develop guidelines and specifications for an operational DINS suitable for use by the military and others developing systems of the future. This document defines twelve overall evaluative questions for use in meeting the second and third objectives of the project and proposes studies that will answer these questions.

  16. The handheld multifunctional thermal imager and surveillance instrument of Jena-Optronik within the German project: IDZ-Infanterist der Zukunft

    Science.gov (United States)

    Krause, U.; Zinner, M.; Fiksel, T.; Krellner, I.; Glasser, W.; Heinrich, J.

    2007-04-01

    Today armed forces of a number of countries develop land warrior integrated, modular combat systems the so called Ground Soldier System. The German version is called "IDZ-Infanterist der Zukunft". This high-technically equipped soldier will have some outstanding capabilities which are based on technical components. One of them will be a handheld multifunctional thermal observation instrument. This light weighted instrument includes a thermal imager which detects an object in 4000m, recognizes it in 3000m and identifies it in 1500m. The IR Image channel can be superposed with the visual daylight image what is taken by an integrated CCD-camera. The image is seen trough a biocular viewer on two Organic Light Emmitting Displays. With the laser range finder which works up to 4000m and the Digital Magnetic Compass it is possible to measure distances and angles and so the own and the target object's positions. This information as well as live time video sequences can be transferred wireless to the soldiers C4I-system. The instrument is based on the surveillance platform NYXUS which was developed in close collaboration with the German Bundeswehr. The NYXUS includes additionally GPS, goniometer and northfinding gyroscope which makes it a precise and irreplaceable tool for nowadays armed forces. The instrument is developed and produced by Jena-Optronik GmbH.

  17. Application of electrical resistivity imaging (ERI) to a tailings dam project for artisanal and small-scale gold mining in Zaruma-Portovelo, Ecuador

    Science.gov (United States)

    Zarroca, Mario; Linares, Rogelio; Velásquez-López, Patricio C.; Roqué, Carles; Rodríguez, Roberto

    2015-02-01

    Thanks to advances in geoelectrical resistivity method over the past two decades, researchers can now gather massive geophysical data sets encompassing long distances and depths, at reasonable cost. The enhanced resolution and spatial coverage of these techniques make them, now, very attractive for use in geological engineering applications, an area for which they were previously charged to be unsuitable. The study shows the capability of electrical resistivity imaging (ERI) to identify key subsoil features that might affect a future tailings dam slated for construction at the Zaruma-Portovelo Mining District, Ecuador. The ERI profiles were gathered and processed with the aim of obtaining resistivity images of a sufficiently resolution for geotechnical use. A geophysical model was created based on these images. The resistivity images were calibrated according to geomorphological, hydrogeological and geotechnical data in order to translate geophysical information into rational geological information. The ERI results, supported by the geomorphological and geotechnical work, suggested that the rock massif is composed of weathering horizons of different rock qualities, slopes are affected by sliding surfaces and these features exert a control on the groundwater flow. These results indicated that the original site selected to construct the dam dike was susceptible to land sliding and an alternative construction site was suggested. Based on the same results, a geomorphological-hydrogeological conceptual model for layered weathered granitic massif in mountainous areas was also proposed.

  18. 'Augmented reality' in conventional simulation by projection of 3-D structures into 2-D images. A comparison with virtual methods

    Energy Technology Data Exchange (ETDEWEB)

    Deutschmann, H.; Nairz, O.; Zehentmayr, F.; Fastner, G.; Sedlmayer, F. [Univ. Clinic for Radiotherapy and Radio-Oncology, Salzburg (Austria); radART - Inst. for research and development on Advanced Radiation Technologies at the Paracelsus Medical Univ., Salzburg (Austria); Steininger, P. [radART - Inst. for research and development on Advanced Radiation Technologies at the Paracelsus Medical Univ., Salzburg (Austria); Dept. of Medical Computer Science and Technology, Univ. for Health Sciences, Hall i. T. (Austria); Kopp, P.; Merz, F.; Wurstbauer, K.; Kranzinger, M.; Kametriser, G.; Kopp, M. [Univ. Clinic for Radiotherapy and Radio-Oncology, Salzburg (Austria)

    2008-02-15

    Background and purpose: in this study, a new method is introduced, which allows the overlay of three-dimensional structures, that have been delineated on transverse slices, onto the fluoroscopy from conventional simulators in real time. Patients and methods: setup deviations between volumetric imaging and simulation were visualized, measured and corrected for 701 patient isocenters. Results: comparing the accuracy to mere virtual simulation lacking additional X-ray imaging, a clear benefit of the new method could be shown. On average, virtual prostate simulations had to be corrected by 0.48 cm (standard deviation [SD] 0.38), and those of the breast by 0.67 cm (SD 0.66). Conclusion: the presented method provides an easy way to determine entity-specific safety margins related to patient setup errors upon registration of bony anatomy (prostate 0.9 cm for 90% of cases, breast 1.3 cm). The important role of planar X-ray imaging was clearly demonstrated. The innovation can also be applied to adaptive image-guided radiotherapy (IGRT) protocols. (orig.)

  19. From Brand Image Research to Teaching Assessment: Using a Projective Technique Borrowed from Marketing Research to Aid an Understanding of Teaching Effectiveness

    Science.gov (United States)

    Boddy, Clive Roland

    2004-01-01

    This paper describes how a simple qualitative market research technique using a projective device called a bubble drawing can be used as a useful feedback device to gain an understanding of students' views of the teaching effectiveness of a market research lecture. Comparisons are made with feedback gained from teaching observations and insights…

  20. SISCAL project

    Science.gov (United States)

    Santer, Richard P.; Fell, Frank

    2003-05-01

    ), combining satellite data, evaluation algorithms and value-adding ancillary digital information. This prevents the end user from investing funds into expensive equipment or to hire specialized personnel. The data processor shall be a generic tool, which may be applied to a large variety of operationally gathered satellite data. In the frame of SISCAL, the processor shall be applied to remotely sensed data of selected coastal areas and lakes in Central Europe and the Eastern Mediterranean, according to the needs of the end users within the SISCAL consortium. A number of measures are required to achieve the objective of the proposed project: (1) Identification and specification of the SISCAL end user needs for NRT water related data products accessible to EO techniques. (2) Selection of the most appropriate instruments, evaluation algorithms and ancillary data bases required to provide the identified data products. (3) Development of the actual Near-Real-Time data processor for the specified EO data products. (4) Development of the GIS processor adding ancillary digital information to the satellite images and providing the required geographical projections. (5) Development of a product retrieval and management system to handle ordering and distribution of data products between the SISCAL server and the end users, including payment and invoicing. (6) Evaluation of the derived data products in terms of accuracy and usefulness by comparison with available in-situ measurements and by making use of the local expertise of the end users. (7) Establishing an Internet server dedicated to internal communication between the consortium members as well as presenting the SISCAL project to a larger public. (8) Marketing activities, presentation of data processor to potential external customers, identification of their exact needs. The innovative aspect of the SISCAL project consists in the generation of NRT data products on water quality parameters from EO data. This article mainly deals

  1. Introduction to the EC's Marie Curie Initial Training Network Project: The European Training Network in Digital Medical Imaging for Radiotherapy (ENTERVISION).

    Science.gov (United States)

    Dosanjh, Manjit; Cirilli, Manuela; Navin, Sparsh

    2015-01-01

    Between 2011 and 2015, the ENTERVISION Marie Curie Initial Training Network has been training 15 young researchers from a variety of backgrounds on topics ranging from in-beam Positron Emission Tomography or Single Particle Tomography techniques, to adaptive treatment planning, optical imaging, Monte Carlo simulations and biological phantom design. This article covers the main research activities, as well as the training scheme implemented by the participating institutes, which included academia, research, and industry.

  2. Image-based virtual tours and 3D modeling of past and current ages for the enhancement of archaeological parks: The VisualVersilia 3D project

    OpenAIRE

    Castagnetti, Cristina; Giannini, Martina; Rivola, Riccardo

    2017-01-01

    The research project VisualVersilia 3D aims at offering a new way to promote the territory and its heritage by matching the traditional reading of the document and the potential use of modern communication technologies for the cultural tourism. Recently, the research on the use of new technologies applied to cultural heritage have turned their attention mainly to technologies to reconstruct and narrate the complexity of the territory and its heritage, including 3D scanning, 3D printing and au...

  3. Project Management

    DEFF Research Database (Denmark)

    Project Management Theory Meets Practice contains the proceedings from the 1st Danish Project Management Research Conference (DAPMARC 2015), held in Copenhagen, Denmark, on May 21st, 2015.......Project Management Theory Meets Practice contains the proceedings from the 1st Danish Project Management Research Conference (DAPMARC 2015), held in Copenhagen, Denmark, on May 21st, 2015....

  4. Project Management

    DEFF Research Database (Denmark)

    Pilkington, Alan; Chai, Kah-Hin; Le, Yang

    2015-01-01

    This paper identifies the true coverage of PM theory through a bibliometric analysis of the International Journal of Project Management from 1996-2012. We identify six persistent research themes: project time management, project risk management, programme management, large-scale project management......, project success/failure and practitioner development. These differ from those presented in review and editorial articles in the literature. In addition, topics missing from the PM BOK: knowledge management project-based organization and project portfolio management have become more popular topics...

  5. Project financing

    International Nuclear Information System (INIS)

    Cowan, A.

    1998-01-01

    Project financing was defined ('where a lender to a specific project has recourse only to the cash flow and assets of that project for repayment and security respectively') and its attributes were described. Project financing was said to be particularly well suited to power, pipeline, mining, telecommunications, petro-chemicals, road construction, and oil and gas projects, i.e. large infrastructure projects that are difficult to fund on-balance sheet, where the risk profile of a project does not fit the corporation's risk appetite, or where higher leverage is required. Sources of project financing were identified. The need to analyze and mitigate risks, and being aware that lenders always take a conservative view and gravitate towards the lowest common denominator, were considered the key to success in obtaining project financing funds. TransAlta Corporation's project financing experiences were used to illustrate the potential of this source of financing

  6. A concept for extraction of habitat features from laser scanning and hypersprectral imaging for evaluation of Natura 2000 sites - the ChangeHabitats2 project approach

    Science.gov (United States)

    Székely, B.; Kania, A.; Pfeifer, N.; Heilmeier, H.; Tamás, J.; Szöllősi, N.; Mücke, W.

    2012-04-01

    The goal of the ChangeHabitats2 project is the development of cost- and time-efficient habitat assessment strategies by employing effective field work techniques supported by modern airborne remote sensing methods, i.e. hyperspectral imagery and laser scanning (LiDAR). An essential task of the project is the design of a novel field work technique that on the one hand fulfills the reporting requirements of the Flora-Fauna-Habitat (FFH-) directive and on the other hand serves as a reference for the aerial data analysis. Correlations between parameters derived from remotely sensed data and terrestrial field measurements shall be exploited in order to create half- or fully-automated methods for the extraction of relevant Natura2000 habitat parameters. As a result of these efforts a comprehensive conceptual model has been developed for extraction and integration of Natura 2000 relevant geospatial data. This scheme is an attempt to integrate various activities within ChangeHabitats2 project defining pathways of development, as well as encompassing existing data processing chains, theoretical approaches and field work. The conceptual model includes definition of processing levels (similar to those existing in remote sensing), whereas these levels cover the range from the raw data to the extracted habitat feature. For instance, the amount of dead wood (standing or lying on the surface) is an important evaluation criterion for the habitat. The tree trunks lying on the ground surface typically can be extracted from the LiDAR point cloud, and the amount of wood can be estimated accordingly. The final result will be considered as a habitat feature derived from laser scanning data. Furthermore, we are also interested not only in the determination of the specific habitat feature, but also in the detection of its variations (especially in deterioration). In this approach the variation of this important habitat feature is considered to be a differential habitat feature, that can

  7. Image construction

    International Nuclear Information System (INIS)

    1976-01-01

    An image processing system fitting in an X-ray television circuit for tomography is described. The profiles registered by the X-ray television circuit are projected on the screen of an afterglow cathode ray tube which registration is convoluted in an analogue system with the help of either a one-dimensional or a two-dimensional convolution function after which it is stored or processed further such that a clear tomogram is obtained

  8. Imaging arrangement and microscope

    Science.gov (United States)

    Pertsinidis, Alexandros; Chu, Steven

    2015-12-15

    An embodiment of the present invention is an imaging arrangement that includes imaging optics, a fiducial light source, and a control system. In operation, the imaging optics separate light into first and second tight by wavelength and project the first and second light onto first and second areas within first and second detector regions, respectively. The imaging optics separate fiducial light from the fiducial light source into first and second fiducial light and project the first and second fiducial light onto third and fourth areas within the first and second detector regions, respectively. The control system adjusts alignment of the imaging optics so that the first and second fiducial light projected onto the first and second detector regions maintain relatively constant positions within the first and second detector regions, respectively. Another embodiment of the present invention is a microscope that includes the imaging arrangement.

  9. Hockey Concussion Education Project, Part 1: Susceptibility-weighted imaging study in male and female ice hockey players over a single season

    Science.gov (United States)

    Helmer, Karl G.; Pasternak, Ofer; Fredman, Eli; Preciado, Ronny I.; Koerte, Inga K.; Sasaki, Takeshi; Mayinger, Michael; Johnson, Andrew M.; Holmes, Jeffrey D.; Forwell, Lorie; Skopelja, Elaine N.; Shenton, Martha E.; Echlin, Paul S.

    2015-01-01

    Object Concussion, or mild traumatic brain injury (mTBI), is a commonly occurring sports-related injury, especially in contact sports such as hockey. Cerebral microbleeds (CMBs), which are small, hypointense lesions on T2*-weighted images, can result from TBI. The authors use susceptibility-weighted imaging (SWI) to automatically detect small hypointensities that may be subtle signs of chronic and acute damage due to both subconcussive and concussive injury. The goal was to investigate how the burden of these hypointensities change over time, over a playing season, and postconcussion, compared with subjects who did not suffer a medically observed and diagnosed concussion. Methods Images were obtained in 45 university-level adult male and female ice hockey players before and after a single Canadian Interuniversity Sports season. In addition, 11 subjects (5 men and 6 women) underwent imaging at 72 hours, 2 weeks, and 2 months after concussion. To identify subtle changes in brain tissue and potential CMBs, nonvessel clusters of hypointensities on SWI were automatically identified and a hypointensity burden index was calculated for all subjects at the beginning of the season (BOS) and the end of the season (EOS), in addition to postconcussion time points (where applicable). Results A statistically significant increase in the hypointensity burden, relative to the BOS, was observed for male subjects at the 2-week postconcussion time point. A smaller, nonsignificant rise in the burden for all female subjects was also observed within the same time period. The difference in hypointensity burden was also statistically significant for men with concussions between the 2-week time point and the BOS. There were no significant changes in burden for nonconcussed subjects of either sex between the BOS and EOS time points. However, there was a statistically significant difference in the burden between male and female subjects in the nonconcussed group at both the BOS and EOS time

  10. Imaging correlated three-particle continuum states. Experiment and theory on the non-adiabatic projection of bound triatomic hydrogen into three separated atoms

    Energy Technology Data Exchange (ETDEWEB)

    Fechner, Peer Cornelis

    2015-07-21

    The central topic of this thesis is the experimental observation and the theoretical modeling of non-adiabatic three-body dissociation of H{sub 3} and D{sub 3} neutral triatomic hydrogen molecules. Our goal is to lend a meaning to the observed momentum vector correlation (MVC) of the three emerging ground state hydrogen atoms, for example H{sub 3}→H(1s)+H(1s)+H(1s), in terms of symmetries of the nuclear molecular wave function and of the non-adiabatic coupling which initiates this decay. In many experiments carried out over the years, a wealth of state specific MVCs was collected by different research groups. The MVCs are imaged in form of so-called Dalitz plots which show a rich structure of maxima and nodal lines, depending on the initial state of the triatomic hydrogen neutral. Theory was slow to catch up with experiment and only by this year, 2015, a general agreement was accomplished. Nevertheless, these models lack of an easy understanding of the underlying physics as many numerical calculations are involved. The theoretical model presented in this thesis follows a different approach which is more guided by the imaging character of our experiments. We concentrate on a rather qualitative treatment by limiting ourselves to the essential ingredients only. This proceeding contributes to giving a physical interpretation of the structures in the Dalitz plots in the following form: Three-particle coincident imaging offers a direct view of the emerging spatial continuum wave function of a predissociating triatomic molecule as it evolves from molecular spatial dimensions into the realm of independent free particles. This latter result is discussed in the context of the so-called Imaging Theorem, the second main part of this work. A third major part of this thesis pertains to obtaining molecular momentum wave functions in separated degrees-of-freedom via Fourier transformation. Even for triatomic hydrogen - the most simple polyatomic molecule - this is a challenging

  11. Project financing

    International Nuclear Information System (INIS)

    Alvarez, M.U.

    1990-01-01

    This paper presents the basic concepts and components of the project financing of large industrial facilities. Diagrams of a simple partnership structure and a simple leveraged lease structure are included. Finally, a Hypothetical Project is described with basic issues identified for discussion purposes. The topics of the paper include non-recourse financing, principal advantages and objectives, disadvantages, project financing participants and agreements, feasibility studies, organization of the project company, principal agreements in a project financing, insurance, and an examination of a hypothetical project

  12. Virtual projects

    DEFF Research Database (Denmark)

    Svejvig, Per; Commisso, Trine Hald

    2012-01-01

    that the best practice knowledge has not permeated sufficiently to the practice. Furthermore, the appropriate application of information and communication technology (ICT) remains a big challenge, and finally project managers are not sufficiently trained in organizing and conducting virtual projects....... The overall implications for research and practice are to acknowledge virtual project management as very different to traditional project management and to address this difference.......Virtual projects are common with global competition, market development, and not least the financial crisis forcing organizations to reduce their costs drastically. Organizations therefore have to place high importance on ways to carry out virtual projects and consider appropriate practices...

  13. Cyclic generalized projection MRI.

    Science.gov (United States)

    Sarty, Gordon E

    2015-04-01

    Progress in the development of portable MRI hinges on the ability to use lightweight magnets that have non-uniform magnetic fields. An image encoding method and mathematical procedure for recovering the image from the NMR signal from non-uniform magnets with closed isomagnetic contours is given. Individual frequencies in an NMR signal from an object in a non-uniform magnetic field give rise to integrals of the object along contours of constant magnetic field: generalized projections. With closed isomagnetic field contours a simple, cyclic, direct reconstruction of the image from the generalized projections is possible when the magnet and RF transmit coil are held fixed relative to the imaged object while the RF receive coil moves. Numerical simulations, using the Shepp and Logan mathematical phantom, were completed to show that the mathematical method works and to illustrate numerical limitations. The method is numerically verified and exact reconstruction demonstrated for discrete mathematical image phantoms. Correct knowledge of the RF receive field is necessary or severe image distortions will result. The cyclic mathematical reconstruction method presented here will be useful for portable MRI schemes that use non-uniform magnets with closed isomagnetic contours along with mechanically or electronically moving the RF receive coils. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Computer image processing and recognition

    Science.gov (United States)

    Hall, E. L.

    1979-01-01

    A systematic introduction to the concepts and techniques of computer image processing and recognition is presented. Consideration is given to such topics as image formation and perception; computer representation of images; image enhancement and restoration; reconstruction from projections; digital television, encoding, and data compression; scene understanding; scene matching and recognition; and processing techniques for linear systems.

  15. Project Temporalities

    DEFF Research Database (Denmark)

    Tryggestad, Kjell; Justesen, Lise; Mouritsen, Jan

    2013-01-01

    into account. Design/methodology/approach – The paper is based on a qualitative case study of a project in the building industry. The authors use actor-network theory (ANT) to analyze the emergence of animal stakeholders, stakes and temporalities. Findings – The study shows how project temporalities can...... into account. This may require investments in new project management technologies. Originality/value – This paper adds to the literatures on project temporalities and stakeholder theory by connecting them to the question of non-human stakeholders and to project management technologies.......Purpose – The purpose of this paper is to explore how animals can become stakeholders in interaction with project management technologies and what happens with project temporalities when new and surprising stakeholders become part of a project and a recognized matter of concern to be taken...

  16. Bright eruptive events polarimeter nanosatellite project: definition and performances of a spectro-imaging instrument onboard a nanosatellite payload for solar flares studies

    Science.gov (United States)

    Triou, Henri Emmanuel

    2016-07-01

    Nanosatellites are currently essentially aimed at training students in the frame of university projects or used as technological demonstrators. As for now, less than one fifth of the nanosatellites have a scientific interest. However, due to the standardization and miniaturization of satellite subsystems such as AOCS and RF systems (onboard X and S band antennas), the nanosatellite platforms can reach performances in terms of attitude control, pointing stability and data transfer at the level needed for scientific missions. In this paper, we present the analysis (definition and performances) of a payload for solar flares studies. Based on miniaturized and high performance X-rays pixelated detectors (Caliste HD), this payload is designed for the observation of solar flares of all classes and will allow photometry, spectroscopy and possibly polarimetry on such events. We show that it can be accommodated on a nanosatellite (CubeSat type) and be operated within the constraints associated to this type of satellites.

  17. Project ethics

    CERN Document Server

    Jonasson, Haukur Ingi

    2013-01-01

    How relevant is ethics to project management? The book - which aims to demystify the field of ethics for project managers and managers in general - takes both a critical and a practical look at project management in terms of success criteria, and ethical opportunities and risks. The goal is to help the reader to use ethical theory to further identify opportunities and risks within their projects and thereby to advance more directly along the path of mature and sustainable managerial practice.

  18. Projective Geometry

    Indian Academy of Sciences (India)

    In painting, this point is sometimes referred to as a 'vanishing point'. We will get back to this device called 'central projection' in mathematics a little later. .... The intersection of a curve of degree m and a curve of degree n has ... projective plane, we get a dual theorem on the second projective plane, which for this reason.

  19. Define Project

    DEFF Research Database (Denmark)

    Munk-Madsen, Andreas

    2005-01-01

    "Project" is a key concept in IS management. The word is frequently used in textbooks and standards. Yet we seldom find a precise definition of the concept. This paper discusses how to define the concept of a project. The proposed definition covers both heavily formalized projects and informally...

  20. Uso de imagens orbitais como base de dados para projetos de reforma agrária The use of orbital images as subsidies to agrarian reform projects

    Directory of Open Access Journals (Sweden)

    Marina de Fátima Vilela

    2005-08-01

    Full Text Available Análises técnica e econômica foram realizadas em imagens dos sensores IKONOS, TM/Landsat 5, ETM+/Landsat 7 e CCD/CBERS, objetivando a verificação da viabilidade destas como base de dados em projetos de reforma agrária. Essas análises efetuadas e a situação de mercado indicaram que a imagem IKONOS apresenta excelente desempenho técnico, mas o custo de aquisição inviabiliza sua utilização como base de dados para a reforma agrária. A imagem do Landsat 7, com baixo custo de aquisição, apresentou grande viabilidade técnica para fins de reforma agrária. No entanto, a perda do contato com a plataforma Landsat 7 inviabilizou a compra de novas imagens do sensor ETM+. A imagem CCD/CBERS apresentou a segunda maior similaridade com a verdade de campo e o menor índice Kappa para a classificação. Apesar do baixo índice de exatidão para a classificação, as análises de custo, o lançamento do CBERS-2 e a possibilidade de correção dos problemas de radiometria podem tornar as imagens da plataforma CBERS-2 concorrentes de peso no mercado e, ainda, preencher a lacuna deixada pela perda do Landsat 7. A imagem do Landsat 5 apresentou o mais baixo desempenho técnico nas análises efetuadas. Entretanto, seu potencial como base de dados é amplamente reconhecido pelo INCRA, que ainda utiliza tais imagens. O declínio da vida útil do Landsat-5 atribui mais importância ao lançamento do CBERS-2.Technical and economical analyses were performed on IKONOS, Landsat TM 5 and Landsat ETM+ 7 and CCD/CBERS data in order to verify their feasibilities to subsidy agrarian reform projects. Results showed that IKONOS data presented excellent technical viability but its high cost prevents its use. Landsat ETM+ 7 data, with low cost, presented good technical viability, however due to the problems occurring in the satellite operation, its use was also prevented . CCD/CBERS data presented the second best similarity with the ground truth data, although it

  1. Speckle Reduction in Projection Systems

    OpenAIRE

    Riechert, Falko

    2009-01-01

    A speckle pattern is a quasi-random interference pattern which typically emerges when lasers are used as illumination sources in projection applications and which severely degrades the image quality. Since in most projection applications high speckle disturbance is not tolerable, speckle reduction is a major issue. This work gives an introduction into the theoretical description of speckle and investigates different practical methods for speckle reduction in laser projection systems.

  2. Annotating Fine Art Images

    OpenAIRE

    Isemann, Daniel

    2007-01-01

    The project's objective is to work with art galleries to help them find innovative ways of indexing images, especially by having automatically created and updated thesauri. National Gallery of Ireland Douglas Hyde Gallery Trinity Long Room Hub

  3. Tropical Rainfall Measuring Mission (TRMM) project. VI - Spacecraft, scientific instruments, and launching rocket. Part 3 - The electrically Scanning Microwave Radiometer and the Special Sensor Microwave/Imager

    Science.gov (United States)

    Wilheit, Thomas T.; Yamasaki, Hiromichi

    1990-01-01

    The two microwave radiometers for TRMM are designed to measure thermal microwave radiation upwelling from the earth. The Electrically Scanning Microwave Radiometer (ESMR) scans from 50 deg to the left through nadir to 50 deg to the right in 78 steps with no moving mechanical parts in a band centered at 19.35 GHz. The TRMM concept uses the radar to develop a climatology of rain-layer thickness which can be used for the interpretation of the radiometer data over a swath wider than the radar. The ESMR data are useful for estimating rain intensity only over an ocean background. The Special Sensor Microwave/Imager (SSM/I), which scans conically with three dual polarized channels at 19, 37, and 85 GHz and a single polarized channel at 22 GHz, provides a wider range of rainfall intensities. The SSM/I spins about an axis parallel to the local spacecraft vector and 128 uniformly spaced samples of the 85 GHz data are taken on each scan over a 112-deg scan region simultaneously with 64 samples of the other frequencies.

  4. Images of Stakeholder Groups Based on Their Environmental Sustainability Linked CSR Projects: A Meta-Analytic Review of Korean Sport Literature

    Directory of Open Access Journals (Sweden)

    Hyun-Duck Kim

    2017-09-01

    Full Text Available Achieving sustainability in sports events requires effective management, political leadership, and ensuring that all stakeholders adhere to a sustainable philosophy. In order to stage a mega-event, tremendous infrastructure and construction are required with significant consumption of private and public resources. Multiple stakeholder groups are recognized as key entities responsible for an efficient trigger of a mega-event. The aim of this study is to conduct a systematic review of Korean sport literature with regard to CSR practices (ES-linked of different stakeholder groups and examine through a meta-analytic methodology their impact on the “images” of these groups. The CMA program was utilized as the main analysis tool to calculate the effect sizes from the selected empirical studies. The results indicated that CSR performance of governmental organizations had the highest effect size level on their own image (brand identity as perceived by visitors and participants. Among the stakeholder groups, effect size levels of their CSR performances were followed by those of corporate sponsors and professional teams. It was found that stakeholder groups are pressured to maintain a balance between financial performance, consumer well-being, and brand identity to bring in external investment.

  5. Image reconstruction using neutrongraphy

    International Nuclear Information System (INIS)

    Crispim, V.R.; Lopes, R.T.; Borges, J.C.

    1986-01-01

    Many factors influence the projections determination in the process of image reconstruction utilizing neutrongraphy technique. In this work it was used the Wiener filter in the projections obtained from one object, in order to minimize the effect of the factors in the quality of the imagem reconstructed. The MART (Multiplicative - Algebraic Reconstruction Technique) algorithim was used. Qualitative and quantitative comparison were done with the original images and the one reconstructed using MART algotithim with and without filter. (Author) [pt

  6. Comparison of primary tumour volumes delineated on four-dimensional computed tomography maximum intensity projection and 18F-fluorodeoxyglucose positron emission tomography computed tomography images of non-small cell lung cancer

    International Nuclear Information System (INIS)

    Duan, Yili; Li, Jianbin; Zhang, Yingjie; Wang, Wei; Fan, Tingyong; Shao, Qian; Xu, Min; Guo, Yanluan; Sun, Xiaorong; Shang, Dongping

    2015-01-01

    The study aims to compare the positional and volumetric differences of tumour volumes based on the maximum intensity projection (MIP) of four-dimensional CT (4DCT) and 18 F-fluorodexyglucose ( 18 F-FDG) positron emission tomography CT (PET/CT) images for the primary tumour of non-small cell lung cancer (NSCLC). Ten patients with NSCLC underwent 4DCT and 18 F-FDG PET/CT scans of the thorax on the same day. Internal gross target volumes (IGTVs) of the primary tumours were contoured on the MIP images of 4DCT to generate IGTV MIP . Gross target volumes (GTVs) based on PET (GTV PET ) were determined with nine different threshold methods using the auto-contouring function. The differences in the volume, position, matching index (MI) and degree of inclusion (DI) of the GTV PET and IGTV MIP were investigated. In volume terms, GTV PET2.0 and GTV PET20% approximated closely to IGTV MIP with mean volume ratio of 0.93 ± 0.45 and 1.06 ± 0.43, respectively. The best MI was between IGTV MIP and GTV PET20% (0.45 ± 0.23). The best DI of IGTV MIP in GTV PET was IGTV MIP in GTV PET20% (0.61 ± 0.26). In 3D PET images, the GTVPET contoured by standardised uptake value (SUV) 2.0 or 20% of maximal SUV (SUV max ) approximate closely to the IGTV MIP in target size, while the spatial mismatch is apparent between them. Therefore, neither of them could replace IGTV MIP in spatial position and form. The advent of 4D PET/CT may improve the accuracy of contouring the perimeter for moving targets.

  7. T2-FLAIR Mismatch, an Imaging Biomarker for IDH and 1p/19q Status in Lower-grade Gliomas: A TCGA/TCIA Project.

    Science.gov (United States)

    Patel, Sohil H; Poisson, Laila M; Brat, Daniel J; Zhou, Yueren; Cooper, Lee; Snuderl, Matija; Thomas, Cheddhi; Franceschi, Ana M; Griffith, Brent; Flanders, Adam E; Golfinos, John G; Chi, Andrew S; Jain, Rajan

    2017-10-15

    Purpose: Lower-grade gliomas (WHO grade II/III) have been classified into clinically relevant molecular subtypes based on IDH and 1p/19q mutation status. The purpose was to investigate whether T2/FLAIR MRI features could distinguish between lower-grade glioma molecular subtypes. Experimental Design: MRI scans from the TCGA/TCIA lower grade glioma database ( n = 125) were evaluated by two independent neuroradiologists to assess (i) presence/absence of homogenous signal on T2WI; (ii) presence/absence of "T2-FLAIR mismatch" sign; (iii) sharp or indistinct lesion margins; and (iv) presence/absence of peritumoral edema. Metrics with moderate-substantial agreement underwent consensus review and were correlated with glioma molecular subtypes. Somatic mutation, DNA copy number, DNA methylation, gene expression, and protein array data from the TCGA lower-grade glioma database were analyzed for molecular-radiographic associations. A separate institutional cohort ( n = 82) was analyzed to validate the T2-FLAIR mismatch sign. Results: Among TCGA/TCIA cases, interreader agreement was calculated for lesion homogeneity [ κ = 0.234 (0.111-0.358)], T2-FLAIR mismatch sign [ κ = 0.728 (0.538-0.918)], lesion margins [ κ = 0.292 (0.135-0.449)], and peritumoral edema [ κ = 0.173 (0.096-0.250)]. All 15 cases that were positive for the T2-FLAIR mismatch sign were IDH -mutant, 1p/19q non-codeleted tumors ( P mismatch sign [ κ = 0.747 (0.536-0.958)]; all 10 cases positive for the T2-FLAIR mismatch sign were IDH -mutant, 1p/19q non-codeleted tumors ( P mismatch sign represents a highly specific imaging biomarker for the IDH -mutant, 1p/19q non-codeleted molecular subtype. Clin Cancer Res; 23(20); 6078-85. ©2017 AACR . ©2017 American Association for Cancer Research.

  8. The TOMO-ETNA experiment: an imaging active campaign at Mt. Etna volcano. Context, main objectives, working-plans and involved research projects

    Directory of Open Access Journals (Sweden)

    Jesús M. Ibáñez

    2016-09-01

    Full Text Available The TOMO-ETNA experiment was devised to image of the crust underlying the volcanic edifice and, possibly, its plumbing system by using passive and active refraction/reflection seismic methods. This experiment included activities both on-land and offshore with the main objective of obtaining a new high-resolution seismic tomography to improve the knowledge of the crustal structures existing beneath the Etna volcano and northeast Sicily up to Aeolian Islands. The TOMO ETNA experiment was divided in two phases. The first phase started on June 15, 2014 and finalized on July 24, 2014, with the withdrawal of two removable seismic networks (a Short Period Network and a Broadband network composed by 80 and 20 stations respectively deployed at Etna volcano and surrounding areas. During this first phase the oceanographic research vessel “Sarmiento de Gamboa” and the hydro-oceanographic vessel “Galatea” performed the offshore activities, which includes the deployment of ocean bottom seismometers (OBS, air-gun shooting for Wide Angle Seismic refraction (WAS, Multi-Channel Seismic (MCS reflection surveys, magnetic surveys and ROV (Remotely Operated Vehicle dives. This phase finished with the recovery of the short period seismic network. In the second phase the Broadband seismic network remained operative until October 28, 2014, and the R/V “Aegaeo” performed additional MCS surveys during November 19-27, 2014. Overall, the information deriving from TOMO-ETNA experiment could provide the answer to many uncertainties that have arisen while exploiting the large amount of data provided by the cutting-edge monitoring systems of Etna volcano and seismogenic area of eastern Sicily.

  9. Dynamic Underground Stripping Project

    International Nuclear Information System (INIS)

    Aines, R.; Newmark, R.; McConachie, W.; Udell, K.; Rice, D.; Ramirez, A.; Siegel, W.; Buettner, M.; Daily, W.; Krauter, P.; Folsom, E.; Boegel, A.J.; Bishop, D.; Udell, K.

    1992-01-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation and underground imaging techniques for use in rapid cleanup of localized underground spills. Called ''Dynamic Stripping'' to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first 8 months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques before moving the contaminated site in FY 92

  10. Electron Paramagnetic Resonance Imaging

    Indian Academy of Sciences (India)

    IAS Admin

    principle behind imaging is to generate profiles of EPR spectra in presence of space-encoding linear field gradients oriented in all directions and uniformly distributed over the surface of a sphere centered on the object. We construct the image with filtered back projection, well known in ultrasound and computerized tomogra ...

  11. Images of the Arctic

    DEFF Research Database (Denmark)

    Brincker, Benedikte

    2017-01-01

    This article examines the photo project and exhibition, Isi-Øje-Eye (2014), using nation building and state formation theories to cast light on the national elements of the project. It addresses the question of how visual images (photographs) are employed to unite Greenland across vast geographical...

  12. SU-G-BRA-04: Simulation of Errors in Maximal Intensity Projection (MIP)-Based Lung Tumor Internal Target Volumes (ITV) Using Real-Time 2D MRI and Deformable Image Registration Based Lung Tumor Tracking

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, D; Kishan, A; Santhanam, A; Min, Y; O’Connell, D; Lamb, J; Cao, M; Agazaryan, N; Yang, Y; Lee, P; Low, D [University of California, Los Angeles, Ca (United States)

    2016-06-15

    Purpose: To evaluate the effect of inter- and intra-fractional tumor motion on the error in four-dimensional computed tomography (4DCT) maximal intensity projection (MIP)–based lung tumor internal target volumes (ITV), using deformable image registration of real-time 2D-sagital cine-mode MRI acquired during lung SBRT treatments. Methods: Five lung tumor patients underwent free breathing SBRT treatment on the ViewRay, with dose prescribed to PTV (4DCT MIP-based ITV+3–6mm margin). Sagittal slice cine-MR images (3.5×3.5mm pixels) were acquired through the center of the tumor at 4 frames per second throughout the treatments (3–4 fractions of 21–32 minutes duration). Tumor GTVs were contoured on the first frame of the cine and tracked throughout the treatment using off-line optical-flow based deformable registration implemented on a GPU cluster. Pseudo-4DCT MIP-based ITVs were generated from MIPs of the deformed GTV contours limited to short segments of image data. All possible pseudo-4DCT MIP-based ITV volumes were generated with 1s resolution and compared to the ITV volume of the entire treatment course. Varying pseudo-4DCT durations from 10-50s were analyzed. Results: Tumors were covered in their entirety by PTV in the patients analysed here. However, pseudo-4DCT based ITV volumes were observed that were as small as 29% of the entire treatment-ITV, depending on breathing irregularity and the duration of pseudo-4DCT. With an increase in duration of pseudo-4DCT from 10–50s the minimum volume acquired from 95% of all pseudo-4DCTs increased from 62%–81% of the treatment ITV. Conclusion: A 4DCT MIP-based ITV offers a ‘snap-shot’ of breathing motion for the brief period of time the tumor is imaged on a specific day. Real time MRI over prolonged periods of time and over multiple treatment fractions shows that the accuracy of this snap-shot varies according to inter- and intra-fractional tumor motion. Further work is required to investigate the dosimetric

  13. Imaging system

    International Nuclear Information System (INIS)

    Froggatt, R.J.

    1981-01-01

    The invention provides a two dimensional imaging system in which a pattern of radiation falling on the system is detected to give electrical signals for each of a plurality of strips across the pattern. The detection is repeated for different orientations of the strips and the whole processed by compensated back projection. For a shadow x-ray system a plurality of strip x-ray detectors are rotated on a turntable. For lower frequencies the pattern may be rotated with a Dove prism and the strips condensed to suit smaller detectors with a cylindrical lens. (author)

  14. OMEGA project

    International Nuclear Information System (INIS)

    Shibuya, E.H.

    1989-01-01

    The OMEGA - Observation of Multiple particle production, Exotic Interactions and Gamma-ray Air Shower-project is presented. The project try to associate photosensitive detectors from experiences of hadronic interactions with electronic detectors used by experiences that investigate extensive atmospheric showers. (M.C.K.)

  15. PROJECT REPORT

    African Journals Online (AJOL)

    medakubu

    We here present a very preliminary report on a field project entitled 'Vanishing. Voices from Ghana's Middle Belt', an Endangered Languages Documentation Project funded by the Endangered Languages Documentation Program based at the School of. Oriental and African Studies, University of London. It is being carried ...

  16. Project Games

    NARCIS (Netherlands)

    Estevez Fernandez, M.A.; Borm, P.E.M.; Hamers, H.J.M.

    2005-01-01

    This paper studies situations in which a project consisting of several activities is not executed as planned.It is divided into three parts.The first part analyzes the case where the activities may be delayed; this possibly induces a delay on the project as a whole with additional costs.Associated

  17. LEX Project

    DEFF Research Database (Denmark)

    Damkilde, Lars; Larsen, Torben J.; Walbjørn, Jacob

    This document is aimed at helping all parties involved in the LEX project to get a common understanding of words, process, levels and the overall concept.......This document is aimed at helping all parties involved in the LEX project to get a common understanding of words, process, levels and the overall concept....

  18. Imaging in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Giussani, Augusto [BfS - Federal Office for Radiation Protection, Oberschleissheim (Germany). Dept. of Radiation Protection and Health; Hoeschen, Christoph (eds.) [Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, Neuherberg (Germany). Research Unit Medical Raditation Physics and Diagnostics

    2013-08-01

    Presents the most recent developments in nuclear medicine imaging, with emphasis on the latest research findings. Considers the latest advances in imaging systems, image reconstruction, noise correction, and quality assurance. Discusses novel concepts, including those developed within the framework of the EURATOM FP7 MADEIRA project. Lists rules of thumb for imaging of use to both beginners and experienced researchers. This volume addresses a wide range of issues in the field of nuclear medicine imaging, with an emphasis on the latest research findings. Initial chapters set the scene by considering the role of imaging in nuclear medicine from the medical perspective and discussing the implications of novel agents and applications for imaging. The physics at the basis of the most modern imaging systems is described, and the reader is introduced to the latest advances in image reconstruction and noise correction. Various novel concepts are then discussed, including those developed within the framework of the EURATOM FP7 MADEIRA research project on the optimization of imaging procedures in order to permit a reduction in the radiation dose to healthy tissues. Advances in quality control and quality assurance are covered, and the book concludes by listing rules of thumb for imaging that will be of use to both beginners and experienced researchers.

  19. Imaging in nuclear medicine

    International Nuclear Information System (INIS)

    Giussani, Augusto; Hoeschen, Christoph

    2013-01-01

    Presents the most recent developments in nuclear medicine imaging, with emphasis on the latest research findings. Considers the latest advances in imaging systems, image reconstruction, noise correction, and quality assurance. Discusses novel concepts, including those developed within the framework of the EURATOM FP7 MADEIRA project. Lists rules of thumb for imaging of use to both beginners and experienced researchers. This volume addresses a wide range of issues in the field of nuclear medicine imaging, with an emphasis on the latest research findings. Initial chapters set the scene by considering the role of imaging in nuclear medicine from the medical perspective and discussing the implications of novel agents and applications for imaging. The physics at the basis of the most modern imaging systems is described, and the reader is introduced to the latest advances in image reconstruction and noise correction. Various novel concepts are then discussed, including those developed within the framework of the EURATOM FP7 MADEIRA research project on the optimization of imaging procedures in order to permit a reduction in the radiation dose to healthy tissues. Advances in quality control and quality assurance are covered, and the book concludes by listing rules of thumb for imaging that will be of use to both beginners and experienced researchers.

  20. Watchdog Project

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Rhett [Schweitzer Engineering Laboratories, Inc., Pullman, WA (United States); Campbell, Jack [CenterPoint Energy Houston Electric, TX (United States); Hadley, Mark [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-12-30

    The Watchdog Project completed 100% of the project Statement of Project Objective (SOPO). The Watchdog project was a very aggressive project looking to accomplish commercialization of technology that had never been commercialized, as a result it took six years to complete not the original three that were planned. No additional federal funds were requested from the original proposal and SEL contributed the additional cost share required to complete the project. The result of the Watchdog Project is the world’s first industrial rated Software Defined Network (SDN) switch commercially available. This technology achieved the SOPOO and DOE Roadmap goals to have strong network access control, improve reliability and network performance, and give the asset owner the ability to minimize attack surface before and during an attack. The Watchdog project is an alliance between CenterPoint Energy Houston Electric, Pacific Northwest National Laboratories (PNNL), and Schweitzer Engineering Laboratories, Inc. (SEL). SEL is the world’s leader in microprocessor-based electronic equipment for protecting electric power systems. PNNL performs basic and applied research to deliver energy, environmental, and national security for our nation. CenterPoint Energy is the third largest publicly traded natural gas delivery company in the U.S and third largest combined electricity and natural gas delivery company. The Watchdog Project efforts were combined with the SDN Project efforts to produce the entire SDN system solution for the critical infrastructure. The Watchdog project addresses Topic Area of Interest 5: Secure Communications, for the DEFOA- 0000359 by protecting the control system local area network itself and the communications coming from and going to the electronic devices on the local network. Local area networks usually are not routed and have little or no filtering capabilities. Combine this with the fact control system protocols are designed with inherent trust the control

  1. Freedom Project

    Directory of Open Access Journals (Sweden)

    Alejandra Suarez

    2014-02-01

    Full Text Available Freedom Project trains prisoners in nonviolent communication and meditation. Two complementary studies of its effects are reported in this article. The first study is correlational; we found decreased recidivism rates among prisoners trained by Freedom Project compared with recidivism rates in Washington state. The second study compared trained prisoners with a matched-pair control group and found improvement in self-reported anger, self-compassion, and certain forms of mindfulness among the trained group. Ratings of role-plays simulating difficult interactions show increased social skills among the group trained by Freedom Project than in the matched controls.

  2. Projective geometry

    CERN Document Server

    Faulkner, Thomas Ewan

    1952-01-01

    This text explores the methods of the projective geometry of the plane. Some knowledge of the elements of metrical and analytical geometry is assumed; a rigorous first chapter serves to prepare readers. Following an introduction to the methods of the symbolic notation, the text advances to a consideration of the theory of one-to-one correspondence. It derives the projective properties of the conic and discusses the representation of these properties by the general equation of the second degree. A study of the relationship between Euclidean and projective geometry concludes the presentation. Nu

  3. Local Radon Descriptors for Image Search

    OpenAIRE

    Babaie, Morteza; Tizhoosh, H. R.; Khatami, Amin; Shiri, M. E.

    2017-01-01

    Radon transform and its inverse operation are important techniques in medical imaging tasks. Recently, there has been renewed interest in Radon transform for applications such as content-based medical image retrieval. However, all studies so far have used Radon transform as a global or quasi-global image descriptor by extracting projections of the whole image or large sub-images. This paper attempts to show that the dense sampling to generate the histogram of local Radon projections has a muc...

  4. Web Based Distributed Coastal Image Analysis System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This project develops Web based distributed image analysis system processing the Moderate Resolution Imaging Spectroradiometer (MODIS) data to provide decision...

  5. Geometrical differences in target volumes based on 18F-fluorodeoxyglucose positron emission tomography/computed tomography and four-dimensional computed tomography maximum intensity projection images of primary thoracic esophageal cancer.

    Science.gov (United States)

    Guo, Y; Li, J; Wang, W; Zhang, Y; Wang, J; Duan, Y; Shang, D; Fu, Z

    2014-01-01

    The objective of the study was to compare geometrical differences of target volumes based on four-dimensional computed tomography (4DCT) maximum intensity projection (MIP) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) images of primary thoracic esophageal cancer for radiation treatment. Twenty-one patients with thoracic esophageal cancer sequentially underwent contrast-enhanced three-dimensional computed tomography (3DCT), 4DCT, and 18F-FDG PET/CT thoracic simulation scans during normal free breathing. The internal gross target volume defined as IGTVMIP was obtained by contouring on MIP images. The gross target volumes based on PET/CT images (GTVPET ) were determined with nine different standardized uptake value (SUV) thresholds and manual contouring: SUV≥2.0, 2.5, 3.0, 3.5 (SUVn); ≥20%, 25%, 30%, 35%, 40% of the maximum (percentages of SUVmax, SUVn%). The differences in volume ratio (VR), conformity index (CI), and degree of inclusion (DI) between IGTVMIP and GTVPET were investigated. The mean centroid distance between GTVPET and IGTVMIP ranged from 4.98 mm to 6.53 mm. The VR ranged from 0.37 to 1.34, being significantly (P<0.05) closest to 1 at SUV2.5 (0.94), SUV20% (1.07), or manual contouring (1.10). The mean CI ranged from 0.34 to 0.58, being significantly closest to 1 (P<0.05) at SUV2.0 (0.55), SUV2.5 (0.56), SUV20% (0.56), SUV25% (0.53), or manual contouring (0.58). The mean DI of GTVPET in IGTVMIP ranged from 0.61 to 0.91, and the mean DI of IGTVMIP in GTVPET ranged from 0.34 to 0.86. The SUV threshold setting of SUV2.5, SUV20% or manual contouring yields the best tumor VR and CI with internal-gross target volume contoured on MIP of 4DCT dataset, but 3DPET/CT and 4DCT MIP could not replace each other for motion encompassing target volume delineation for radiation treatment. © 2014 International Society for Diseases of the Esophagus.

  6. Dimensionality reduction with image data

    OpenAIRE

    Peña, Daniel; Benito, Mónica

    2004-01-01

    A common objective in image analysis is dimensionality reduction. The most common often used data-exploratory technique with this objective is principal component analysis. We propose a new method based on the projection of the images as matrices after a Procrustes rotation and show that it leads to a better reconstruction of images.

  7. Project Management

    DEFF Research Database (Denmark)

    Kampf, Constance

    2009-01-01

    In this video Associate Professor Constance Kampf talks about the importance project management. Not only as a tool in implementation, but also as a way of thinking, and as something that needs to be considered from idea conception......In this video Associate Professor Constance Kampf talks about the importance project management. Not only as a tool in implementation, but also as a way of thinking, and as something that needs to be considered from idea conception...

  8. Efficacy on maximum intensity projection of contrast-enhanced 3D spin echo imaging with improved motion-sensitized driven-equilibrium preparation in the detection of brain metastases

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Yun Jung; Choi, Byung Se; Yoon, Yeon Hong; Woo, Leonard Sun; Jung, Cheol Kyu; Kim, Jae Hyoung [Dept. of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Lee, Kyung Mi [Dept. of Radiology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul (Korea, Republic of)

    2017-08-01

    To evaluate the diagnostic benefits of 5-mm maximum intensity projection of improved motion-sensitized driven-equilibrium prepared contrast-enhanced 3D T1-weighted turbo-spin echo imaging (MIP iMSDE-TSE) in the detection of brain metastases. The imaging technique was compared with 1-mm images of iMSDE-TSE (non-MIP iMSDE-TSE), 1-mm contrast-enhanced 3D T1-weighted gradient-echo imaging (non-MIP 3D-GRE), and 5-mm MIP 3D-GRE. From October 2014 to July 2015, 30 patients with 460 enhancing brain metastases (size > 3 mm, n = 150; size ≤ 3 mm, n = 310) were scanned with non-MIP iMSDE-TSE and non-MIP 3D-GRE. We then performed 5-mm MIP reconstruction of these images. Two independent neuroradiologists reviewed these four sequences. Their diagnostic performance was compared using the following parameters: sensitivity, reading time, and figure of merit (FOM) derived by jackknife alternative free-response receiver operating characteristic analysis. Interobserver agreement was also tested. The mean FOM (all lesions, 0.984; lesions ≤ 3 mm, 0.980) and sensitivity ([reader 1: all lesions, 97.3%; lesions ≤ 3 mm, 96.2%], [reader 2: all lesions, 97.0%; lesions ≤ 3 mm, 95.8%]) of MIP iMSDE-TSE was comparable to the mean FOM (0.985, 0.977) and sensitivity ([reader 1: 96.7, 99.0%], [reader 2: 97, 95.3%]) of non-MIP iMSDE-TSE, but they were superior to those of non-MIP and MIP 3D-GREs (all, p < 0.001). The reading time of MIP iMSDE-TSE (reader 1: 47.7 ± 35.9 seconds; reader 2: 44.7 ± 23.6 seconds) was significantly shorter than that of non-MIP iMSDE-TSE (reader 1: 78.8 ± 43.7 seconds, p = 0.01; reader 2: 82.9 ± 39.9 seconds, p < 0.001). Interobserver agreement was excellent (κ > 0.75) for all lesions in both sequences. MIP iMSDE-TSE showed high detectability of brain metastases. Its detectability was comparable to that of non-MIP iMSDE-TSE, but it was superior to the detectability of non-MIP/MIP 3D-GREs. With a shorter reading time, the false-positive results of MIP i

  9. Imaging in nuclear medicine

    CERN Document Server

    Hoeschen, Christoph

    2013-01-01

    This volume addresses a wide range of issues in the field of nuclear medicine imaging, with an emphasis on the latest research findings. Initial chapters set the scene by considering the role of imaging in nuclear medicine from the medical perspective and discussing the implications of novel agents and applications for imaging. The physics at the basis of the most modern imaging systems is described, and the reader is introduced to the latest advances in image reconstruction and noise correction. Various novel concepts are then discussed, including those developed within the framework of the EURATOM FP7 MADEIRA research project on the optimization of imaging procedures in order to permit a reduction in the radiation dose to healthy tissues. Advances in quality control and quality assurance are covered, and the book concludes by listing rules of thumb for imaging that will be of use to both beginners and experienced researchers.

  10. Image Sampling with Quasicrystals

    Directory of Open Access Journals (Sweden)

    Mark Grundland

    2009-07-01

    Full Text Available We investigate the use of quasicrystals in image sampling. Quasicrystals produce space-filling, non-periodic point sets that are uniformly discrete and relatively dense, thereby ensuring the sample sites are evenly spread out throughout the sampled image. Their self-similar structure can be attractive for creating sampling patterns endowed with a decorative symmetry. We present a brief general overview of the algebraic theory of cut-and-project quasicrystals based on the geometry of the golden ratio. To assess the practical utility of quasicrystal sampling, we evaluate the visual effects of a variety of non-adaptive image sampling strategies on photorealistic image reconstruction and non-photorealistic image rendering used in multiresolution image representations. For computer visualization of point sets used in image sampling, we introduce a mosaic rendering technique.

  11. Project mobilisation

    International Nuclear Information System (INIS)

    Clark, J.; Limbrick, A.

    1996-01-01

    This paper identifies and reviews the issues to be addressed and the procedures to be followed during the mobilisation of projects using LFG as an energy source. Knowledge of the procedures involved in project mobilisation, their sequence and probable timescales, is essential for efficient project management. It is assumed that the majority of projects will be situated on existing, licensed landfill sites and, in addition to complying with the relevant conditions of the waste management licence and original planning consent, any proposed developments on the site will require a separate planning consent. Experience in the UK indicates that obtaining planning permission rarely constitutes a barrier to the development of schemes for the utilisation of LFG. Even so, an appreciation of the applicable environmental and planning legislation is essential as this will enable the developer to recognise the main concerns of the relevant planning authority at an early stage of the project, resulting in the preparation of an informed and well-structured application for planning permission. For a LFG utilisation scheme on an existing landfill site, the need to carry out an environmental assessment (EA) as part of the application for planning permission will, in vitually all cases, be discretionary. Even if not deemed necessary by the planning authority, an EA is a useful tool at the planning application stage, to identify and address potential problems and to support discussions with bodies such as the Environment Agency, from whom consents or authorisations may be required. Carrying out an EA can thus provide for more cost-effective project development and enhanced environmental protection. Typically, the principal contractual arrangements, such as the purchase of gas or the sale of electricity, will have been established before the project mobilisation phase. However, there are many other contractural arrangements that must be established, and consents and permits that may be

  12. The High resolution Coronal Imager Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The telescope design is a direct continuation of the development from NIXT to TRACE and AIA: we propose a Ritchey-Chr´etien with plate scale sufficient to...

  13. The BIRN Project: Imaging the Nervous System

    International Nuclear Information System (INIS)

    Ellisman, Mark

    2006-01-01

    The grand goal in neuroscience research is to understand how the interplay of structural, chemical and electrical signals in nervous tissue gives rise to behavior. Experimental advances of the past decades have given the individual neuroscientist an increasingly powerful arsenal for obtaining data, from the level of molecules to nervous systems. Scientists have begun the arduous and challenging process of adapting and assembling neuroscience data at all scales of resolution and across disciplines into computerized databases and other easily accessed sources. These databases will complement the vast structural and sequence databases created to catalogue, organize and analyze gene sequences and protein products. The general premise of the neuroscience goal is simple; namely that with 'complete' knowledge of the genome and protein structures accruing rapidly we next need to assemble an infrastructure that will facilitate acquisition of an understanding for how functional complexes operate in their cell and tissue contexts.

  14. Automated Analysis of Imaging Based Experiments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For many applications involving liquid injection, the ability to predict the details of the breakup process is often limited due to the complexity of the two-phase...

  15. Plenoptic Imager for Automated Surface Navigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous and semi-autonomous robotic systems require information about their surroundings in order to navigate properly. A video camera machine vision system can...

  16. Sparse seismic imaging using variable projection

    NARCIS (Netherlands)

    Aravkin, Aleksandr Y.; Tu, Ning; van Leeuwen, Tristan

    2013-01-01

    We consider an important class of signal processing problems where the signal of interest is known to be sparse, and can be recovered from data given auxiliary information about how the data was generated. For example, a sparse Green's function may be recovered from seismic experimental data using

  17. Mammographic Image Enhancement

    International Nuclear Information System (INIS)

    Md Saion Salikin; Asmaliza Hashim; Wan Hazlinda Ismail; Azuhar Ripin; Norriza Mohd Isa; Mak Chee Hoe

    2005-01-01

    Its main aim is to process an image by utilizing enhancement techniques so that the enhanced image is better and more suitable than the original image for specific application. The objective of the project is to enhance the mammography image by using Interactive Data Language (IDL) software with some of the selected enhancement technique. In order to obtain the best enhanced image, the mammograms with different setting are prepared and the best mammography image is selected by using manual mode with technical factors 28 kV and 56.3 mAs namely 12 mA tube current and 0.45 second time exposure. This paper highlights four enhancement techniques that are chosen and the variables of each algorithm of the techniques are determined. The enhancement techniques used are image clipping technique with image clipped 21% at low ends and 5% at high ends, filtering technique with low pass filter, unsharp masking technique by creating a mask using a low pass filter and global histogram equalization. There are 24 technique permutations produced by the four enhancement techniques chosen, according to order of the enhancement technique applied on a particular mammographic image. These technique permutations are applied to the image using IDL. The enhancement technique permutation of histogram equalization, unsharp masking technique, filtering technique and image clipping technique, that produce the best enhanced image is determined qualitatively. The results of enhancement techniques by using IDL are presented in brief in this presentation. (Author)

  18. Neutron Dark-Field Imaging

    Science.gov (United States)

    Mullins, David

    2017-09-01

    Neutron imaging is typically used to image and reconstruct objects that are difficult to image using X-Ray imaging techniques. X-Ray absorption is primarily determined by the electron density of the material. This makes it difficult to image objects within materials that have high densities such as metal. However, the neutron scattering cross section primarily depends on the strong nuclear force, which varies somewhat randomly across the periodic table. In this project, an imaging technique known as dark field imaging using a far-field interferometer has been used to study a sample of granite. With this technique, interferometric phase images are generated. The dispersion of the microstructure of the sample dephases the beam, reducing the visibility. Collecting tomographic projections at different autocorrelation lengths (from 100 nanometers to 1.74 micrometers) essentially creates a 3D small angle scattering pattern, enabling mapping of how the microstructure is distributed throughout the sample.

  19. Project studies

    DEFF Research Database (Denmark)

    Geraldi, Joana; Söderlund, Jonas

    2018-01-01

    Project organising is a growing field of scholarly inquiry and management practice. In recent years, two important developments have influenced this field: (1) the study and practice of projects have extended their level of analysis from mainly focussing on individual projects to focussing on micro...... of 'organising' filled the field of organisation studies with new ideas and intellectual challenges. To take advantage of such developments, organisational scholars had to consider different forms of organising as part of 'organisation studies', and continuously adapt their frames of reference and forms...... by emancipatory interest and the pragmatic desire for changes in the status quo through the reorganisation of inherent contradictions, giving voice to minorities while addressing major economic and social problems. We termed them type 1, type 2 and type 3, respectively.The juxtaposition of levels of analysis...

  20. Projection displays

    Science.gov (United States)

    Chiu, George L.; Yang, Kei H.

    1998-08-01

    Projection display in today's market is dominated by cathode ray tubes (CRTs). Further progress in this mature CRT projector technology will be slow and evolutionary. Liquid crystal based projection displays have gained rapid acceptance in the business market. New technologies are being developed on several fronts: (1) active matrix built from polysilicon or single crystal silicon; (2) electro- optic materials using ferroelectric liquid crystal, polymer dispersed liquid crystals or other liquid crystal modes, (3) micromechanical-based transducers such as digital micromirror devices, and grating light valves, (4) high resolution displays to SXGA and beyond, and (5) high brightness. This article reviews the projection displays from a transducer technology perspective along with a discussion of markets and trends.

  1. Image processing in medical ultrasound

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian

    This Ph.D project addresses image processing in medical ultrasound and seeks to achieve two major scientific goals: First to develop an understanding of the most significant factors influencing image quality in medical ultrasound, and secondly to use this knowledge to develop image processing...... multiple imaging setups. This makes the system well suited for development of new processing methods and for clinical evaluations, where acquisition of the exact same scan location for multiple methods is important. The second project addressed implementation, development and evaluation of SASB using...... methods for enhancing the diagnostic value of medical ultrasound. The project is an industrial Ph.D project co-sponsored by BK Medical ApS., with the commercial goal to improve the image quality of BK Medicals scanners. Currently BK Medical employ a simple conventional delay-and-sum beamformer to generate...

  2. Greenland Telescope (GLT Project

    Directory of Open Access Journals (Sweden)

    Nakamura M.

    2013-12-01

    Full Text Available The GLT project is deploying a new submillimeter (submm VLBI station in Greenland. Our primary scientific goal is to image a shadow of the supermassive black hole (SMBH of six billion solar masses in M87 at the center of the Virgo cluster of galaxies. The expected SMBH shadow size of 40-50 μas requires superbly high angular resolution, suggesting that the submm VLBI would be the only way to obtain the shadow image. The Summit station in Greenland enables us to establish baselines longer than 9,000 km with ALMA in Chile and SMA in Hawaii as well as providing a unique u–v coverage for imaging M87. Our VLBI network will achieve a superior angular resolution of about 20 μas at 350 GHz, corresponding to ∼ 2.5 times of the Schwarzschild radius of the supermassive black hole in M87. We have been monitoring the atmospheric opacity at 230 GHz since August. 2011; we have confirmed the value on site during the winter season is comparable to the ALMA site thanks to high altitude of 3,200 m and low temperature of −50°C. We will report current status and future plan of the GLT project towards our expected first light on 2015–2016.

  3. Project summary

    Energy Technology Data Exchange (ETDEWEB)

    Dungee, Ryan [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-22

    Telescope surveys have given us a great deal of information about our universe, but the images they capture carry with them an inherent limitation. The question then is how do we take this information to the next level? The answer: the Dark Energy Spectroscopic Instrument (DESI). DESI is an instrument that will measure the distance to tens of millions of galaxies in our night sky. This information can be combined with already existing images to construct a three dimensional map of our universe providing a great deal of new opportunities for cosmological research.

  4. Echo project

    DEFF Research Database (Denmark)

    Gfader, Verina; Carson, Rebecca; Kraus, Chris

    2016-01-01

    Echo project (ed. by Verina Gfader and Ruth Höflich) is an online publication and community board that developed from a visit to the Los Angeles Art Book fair in January 2014. It was on the occasion of a prior book project, titled Prospectus, that the editorial team had been invited by the LAABF...... team to both present the printed matter in the format of running a book stall, and stage a discursive event at the Classroom. Echo reverberates some of the encounters and debates there, with new commissioned chapters propelling a ongoing correspondence across urban environs: An essay on the General...

  5. The Sungrazer Citizen Science Project

    Science.gov (United States)

    Battams, K.

    2016-12-01

    The NASA-funded Sungrazer Project is one of the oldest and most successful Citizen Science projects, having more than doubled the number of officially designated comets since it became public in 2002. The Sungrazer Project has enabled the discovery of more than 3,100 previously unknown near-Sun and Sungrazing comets in images returned by the joint ESA-NASA Solar and Heliospheric Observatory (SOHO), which was launched in 1995, and the NASA Solar Terrestrial Relations Observatories (STEREO), launched in 2006. The Sungrazer Project offers a centralized web site for amateur astronomers ("comet hunters") to report potential comets in SOHO and STEREO data, which the Project PI then confirms/rejects. It is then the task of the Project PI to perform precise astrometric measurements of all new comets, and supply the resulting data to the Minor Planet Center for official orbit determinations and designation. Almost 100 individuals from all over the world have discovered comets via the Project, with successful participants as young as 13-years old. In this talk I will discuss the history of the project, report the current discovery statistics, and highlight a few of the major discoveries enabled by the Project. I will also discuss the logistic of the program, participation requirements, day-to-day operations, and outreach efforts. Finally I will present an outlook for the project with respect to future space-based heliophysics missions.

  6. International Atomic Energy Agency Coordinated Research Project on Application of 3D Neutron Imaging and Tomography in Cultural Heritage Research. Report of the first Research Co-ordination Meeting

    International Nuclear Information System (INIS)

    2012-01-01

    Experts from the participating IAEA Member States presented their individual reports on their activities on Neutron Imaging (NI) as well as on Cultural Heritage (CH) studies. The participants also presented an overview of their facilities, ranging from conventional to advanced, and their plans for implementing or improving NI. From the presentations of the delegates it is evident that the current existing NI technology provides a unique non-destructive bulk analytical capability to the CH community. This technology entails 2-dimensional and 3-dimensional results, and is available at about 16 well equipped facilities throughout the world.The presentations also reported new techniques under development in NI which will be capable to further support the needs expressed by the CH community. These techniques expand the capability of the existing NI technology in the field of structural, chemical and elemental analysis. The CH-community favours non-invasive techniques to characterize their research objects, which include irreplaceable unique findings recovered from Archaeological-, Palaeontologic-, Human evolution- and Historical sites. Answers needed include identification of ancient manufacturing technology, detection of hidden features and objects, mensuration, authentication, provenance and identification of the best ways of conservation, etc. The experts welcome the initiation of a CRP to harmonize selected Neutron-based Imaging techniques in order to provide state-of-the-art end user services in the area of CH research. The CRP promotes NI technology utilization in all Member States, especially those in developing countries in order to encourage exploitation of all types of neutron sources for NI through CH research activities. These activities will establish and strengthen collaborations between the NI specialists and researchers from the CH community beyond the 3-year lifetime of this project. Standardization procedures and methodologies were addressed to achieve

  7. SU-F-J-192: A Quick and Effective Method to Validate Patient’s Daily Setup and Geometry Changes Prior to Proton Treatment Delivery Based On Water Equivalent Thickness Projection Imaging (WETPI) for Head Neck Cancer (HNC) Patient

    Energy Technology Data Exchange (ETDEWEB)

    Liu, G; Qin, A; Zhang, J; Li, X; Zhou, J; Yan, D; Teo, B; Chen, P; Krauss, D; Kabolizadeh, P; Guerrero, T; Stevens, C; Liang, J; Ding, X [Beaumont Health System, Royal Oak, MI (United States); University of Pennsylvania, Philadelphia, PA (United States); Wuhan University, Wuhan (China)

    2016-06-15

    Purpose: With the implementation of Cone-beam Computed-Tomography (CBCT) in proton treatment, we introduces a quick and effective tool to verify the patient’s daily setup and geometry changes based on the Water-Equivalent-Thickness Projection-Image(WETPI) from individual beam angle. Methods: A bilateral head neck cancer(HNC) patient previously treated via VMAT was used in this study. The patient received 35 daily CBCT during the whole treatment and there is no significant weight change. The CT numbers of daily CBCTs were corrected by mapping the CT numbers from simulation CT via Deformable Image Registration(DIR). IMPT plan was generated using 4-field IMPT robust optimization (3.5% range and 3mm setup uncertainties) with beam angle 60, 135, 300, 225 degree. WETPI within CTV through all beam directions were calculated. 3%/3mm gamma index(GI) were used to provide a quantitative comparison between initial sim-CT and mapped daily CBCT. To simulate an extreme case where human error is involved, a couch bar was manually inserted in front of beam angle 225 degree of one CBCT. WETPI was compared in this scenario. Results: The average of GI passing rate of this patient from different beam angles throughout the treatment course is 91.5 ± 8.6. In the cases with low passing rate, it was found that the difference between shoulder and neck angle as well as the head rest often causes major deviation. This indicates that the most challenge in treating HNC is the setup around neck area. In the extreme case where a couch bar is accidently inserted in the beam line, GI passing rate drops to 52 from 95. Conclusion: WETPI and quantitative gamma analysis give clinicians, therapists and physicists a quick feedback of the patient’s setup accuracy or geometry changes. The tool could effectively avoid some human errors. Furthermore, this tool could be used potentially as an initial signal to trigger plan adaptation.

  8. SU-F-T-191: 4D Dose Reconstruction of Intensity Modulated Proton Therapy (IMPT) Based On Breathing Probability Density Function (PDF) From 4D Cone Beam Projection Images: A Study for Lung Treatment

    International Nuclear Information System (INIS)

    Zhou, J; Ding, X; Liang, J; Zhang, J; Wang, Y; Yan, D

    2016-01-01

    Purpose: With energy repainting in lung IMPT, the dose delivered is approximate to the convolution of dose in each phase with corresponding breathing PDF. This study is to compute breathing PDF weighted 4D dose in lung IMPT treatment and compare to its initial robust plan. Methods: Six lung patients were evaluated in this study. Amsterdam shroud image were generated from pre-treatment 4D cone-beam projections. Diaphragm motion curve was extract from the shroud image and the breathing PDF was generated. Each patient was planned to 60 Gy (12GyX5). In initial plans, ITV density on average CT was overridden with its maximum value for planning, using two IMPT beams with robust optimization (5mm uncertainty in patient position and 3.5% range uncertainty). The plan was applied to all 4D CT phases. The dose in each phase was deformed to a reference phase. 4D dose is reconstructed by summing all these doses based on corresponding weighting from the PDF. Plan parameters, including maximum dose (Dmax), ITV V100, homogeneity index (HI=D2/D98), R50 (50%IDL/ITV), and the lung-GTV’s V12.5 and V5 were compared between the reconstructed 4D dose to initial plans. Results: The Dmax is significantly less dose in the reconstructed 4D dose, 68.12±3.5Gy, vs. 70.1±4.3Gy in the initial plans (p=0.015). No significant difference is found for the ITV V100, HI, and R50, 92.2%±15.4% vs. 96.3%±2.5% (p=0.565), 1.033±0.016 vs. 1.038±0.017 (p=0.548), 19.2±12.1 vs. 18.1±11.6 (p=0.265), for the 4D dose and initial plans, respectively. The lung-GTV V12.5 and V5 are significantly high in the 4D dose, 13.9%±4.8% vs. 13.0%±4.6% (p=0.021) and 17.6%±5.4% vs. 16.9%±5.2% (p=0.011), respectively. Conclusion: 4D dose reconstruction based on phase PDF can be used to evaluate the dose received by the patient. A robust optimization based on the phase PDF may even further improve patient care.

  9. Imaging systems in nuclear medicine and image evaluation

    International Nuclear Information System (INIS)

    Beck, R.; Charleston, D.; Metz, C.

    1980-01-01

    This project deals with imaging systems in nuclear medicine and image evaluation and is presented as four subprojects. The goal of the first subproject is to improve diagnositc image quality by development of a general computer code for optimizing collimator design. The second subproject deals with a secondary emission and fluorescence technique for thyroid scanning while the third subproject emphasizes the need for more sophisticated image processing systems such as coherent optical spatial filtering systems and digital image processing. The fourth subproject presents a new approach for processing image data by taking into account the energy of each detected gamma-ray photon

  10. Project Narrative

    Energy Technology Data Exchange (ETDEWEB)

    Driscoll, Mary C. [St. Bonaventure University, St Bonaventure, NY(United States)

    2012-07-12

    The Project Narrative describes how the funds from the DOE grant were used to purchase equipment for the biology, chemistry, physics and mathematics departments. The Narrative also describes how the equipment is being used. There is also a list of the positive outcomes as a result of having the equipment that was purchased with the DOE grant.

  11. Projection Methods

    DEFF Research Database (Denmark)

    Wagner, Falko Jens; Poulsen, Mikael Zebbelin

    1999-01-01

    When trying to solve a DAE problem of high index with more traditional methods, it often causes instability in some of the variables, and finally leads to breakdown of convergence and integration of the solution. This is nicely shown in [ESF98, p. 152 ff.].This chapter will introduce projection...

  12. Hydrology Project

    International Nuclear Information System (INIS)

    Anon.

    Research carried out in the 'Hydrology Project' of the Centro de Energia Nuclear na Agricultura', Piracicaba, Sao Paulo State, Brazil, are described. Such research comprises: Amazon hydrology and Northeast hydrology. Techniques for the measurement of isotope ratios are used. (M.A.) [pt

  13. Project Lifescape

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 8. Project Lifescape – An Invitation. Madhav Gadgil. Classroom Volume 4 Issue 8 August 1999 pp 80-90. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/004/08/0080-0090. Author Affiliations.

  14. Project Avatar

    DEFF Research Database (Denmark)

    Juhlin, Jonas Alastair

    'Project Avatar' tager udgangspunkt i den efterretningsdisciplin, der kaldes Open Source Intelligence og indebærer al den information, som ligger frit tilgængeligt i åbne kilder. Med udbredelsen af sociale medier åbners der op for helt nye typer af informationskilder. Spørgsmålet er; hvor nyttig er...

  15. FLOAT Project

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.; Aarup, Bendt

    The objective of the FLOAT project is to study the reliability of high-performance fibre-reinforced concrete, also known as Compact Reinforced Composite (CRC), for the floats of wave energy converters. In order to reach a commercial breakthrough, wave energy converters need to achieve a lower price...

  16. Project Baltia

    Index Scriptorium Estoniae

    2007-01-01

    Uus arhitektuuriajakiri "Project Baltia" tutvustab Baltimaade, Soome ja Peterburi regiooni arhitektuuri, linnaehitust ja disaini. Ilmub neli korda aastas inglise- ja venekeelsena. Väljaandja: kirjastus Balticum Peterburis koostöös Amsterdami ja Moskva kirjastusega A-Fond. Peatoimetaja Vladimir Frolov

  17. Project COLD.

    Science.gov (United States)

    Kazanjian, Wendy C.

    1982-01-01

    Describes Project COLD (Climate, Ocean, Land, Discovery) a scientific study of the Polar Regions, a collection of 35 modules used within the framework of existing subjects: oceanography, biology, geology, meterology, geography, social science. Includes a partial list of topics and one activity (geodesic dome) from a module. (Author/SK)

  18. Project Success.

    Science.gov (United States)

    Baehr, Rufus F.

    This report reviews the remedial education program--Project Success--at the Urban Education Center, City Colleges of Chicago (Illinois). The major features of the program are outlined and its operation and evaluation are discussed. Student performance and characteristics are then tabularly compared, based on their groupings as…

  19. Radiochemistry Project

    International Nuclear Information System (INIS)

    Anon.

    Researches carried out in the 'Radiochemistry Project' of the Agricultural Nuclear Energy Center, Piracicaba, Sao Paulo State, Brazil, are described. Such researches comprise: dosimetry and radiological protection; development of techniques and methods of chemical analysis and radiochemistry. (M.A.) [pt

  20. THE PROJECT

    Directory of Open Access Journals (Sweden)

    P.M. Latyshev

    2008-09-01

    Full Text Available "Urals Industrial - Urals Polar" is the unique project and thus it will provide the economic security not only of the local territory but of the whole Russia in terms of several courses. This article is devoted to the main courses of these ones and their influence on the economy of the country.

  1. Project Reconstruct.

    Science.gov (United States)

    Helisek, Harriet; Pratt, Donald

    1994-01-01

    Presents a project in which students monitor their use of trash, input and analyze information via a database and computerized graphs, and "reconstruct" extinct or endangered animals from recyclable materials. The activity was done with second-grade students over a period of three to four weeks. (PR)

  2. SDN Project

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Rhett [Schweitzer Engineering Laboratories Inc, Pullman, WA (United States)

    2016-12-23

    The SDN Project completed on time and on budget and successfully accomplished 100% of the scope of work outlined in the original Statement of Project Objective (SOPO). The SDN Project formed an alliance between Ameren Corporation, University of Illinois Urbana- Champaign (UIUC), Pacific Northwest National Laboratories (PNNL), and Schweitzer Engineering Laboratories, Inc. (SEL). The objective of the SDN Project is to address Topic Area of Interest 2: Sustain critical energy delivery functions while responding to a cyber-intrusion under Funding Opportunity Announcement DE-FOA-0000797. The goal of the project is to design and commercially release technology that provides a method to sustain critical energy delivery functions during a cyber intrusion and to do this control system operators need the ability to quickly identify and isolate the affected network areas, and re-route critical information and control flows around. The objective of the SDN Project is to develop a Flow Controller that monitors, configures, and maintains the safe, reliable network traffic flows of all the local area networks (LANs) on a control system in the Energy sector. The SDN team identified the core attributes of a control system and produced an SDN flow controller that has the same core attributes enabling networks to be designed, configured and deployed that maximize the whitelisted, deny-bydefault and purpose built networks. This project researched, developed and commercially released technology that: Enables all field networks be to configured and monitored as if they are a single asset to be protected; Enables greatly improved and even precalculated response actions to reliability and cyber events; Supports pre-configured localized response actions tailored to provide resilience against failures and centralized response to cyber-attacks that improve network reliability and availability; Architecturally enables the right subject matter experts, who are usually the information

  3. Mammography image compression using Wavelet

    International Nuclear Information System (INIS)

    Azuhar Ripin; Md Saion Salikin; Wan Hazlinda Ismail; Asmaliza Hashim; Norriza Md Isa

    2004-01-01

    Image compression plays an important role in many applications like medical imaging, televideo conferencing, remote sensing, document and facsimile transmission, which depend on the efficient manipulation, storage, and transmission of binary, gray scale, or color images. In Medical imaging application such Picture Archiving and Communication System (PACs), the image size or image stream size is too large and requires a large amount of storage space or high bandwidth for communication. Image compression techniques are divided into two categories namely lossy and lossless data compression. Wavelet method used in this project is a lossless compression method. In this method, the exact original mammography image data can be recovered. In this project, mammography images are digitized by using Vider Sierra Plus digitizer. The digitized images are compressed by using this wavelet image compression technique. Interactive Data Language (IDLs) numerical and visualization software is used to perform all of the calculations, to generate and display all of the compressed images. Results of this project are presented in this paper. (Author)

  4. Projective geometry and projective metrics

    CERN Document Server

    Busemann, Herbert

    2005-01-01

    The basic results and methods of projective and non-Euclidean geometry are indispensable for the geometer, and this book--different in content, methods, and point of view from traditional texts--attempts to emphasize that fact. Results of special theorems are discussed in detail only when they are needed to develop a feeling for the subject or when they illustrate a general method. On the other hand, an unusual amount of space is devoted to the discussion of the fundamental concepts of distance, motion, area, and perpendicularity.Topics include the projective plane, polarities and conic sectio

  5. Micromachined Integrated Transducers for Ultrasound Imaging

    DEFF Research Database (Denmark)

    la Cour, Mette Funding

    The purpose of this project is to develop capacitive micromachined ultrasonic transducers (CMUTs) for medical imaging. Medical ultrasound transducers used today are fabricated using piezoelectric materials and bulk processing. To fabricate transducers capable of delivering a higher imaging...

  6. Overview of image reconstruction

    International Nuclear Information System (INIS)

    Marr, R.B.

    1980-04-01

    Image reconstruction (or computerized tomography, etc.) is any process whereby a function, f, on R/sup n/ is estimated from empirical data pertaining to its integrals, ∫f(x) dx, for some collection of hyperplanes of dimension k < n. The paper begins with background information on how image reconstruction problems have arisen in practice, and describes some of the application areas of past or current interest; these include radioastronomy, optics, radiology and nuclear medicine, electron microscopy, acoustical imaging, geophysical tomography, nondestructive testing, and NMR zeugmatography. Then the various reconstruction algorithms are discussed in five classes: summation, or simple back-projection; convolution, or filtered back-projection; Fourier and other functional transforms; orthogonal function series expansion; and iterative methods. Certain more technical mathematical aspects of image reconstruction are considered from the standpoint of uniqueness, consistency, and stability of solution. The paper concludes by presenting certain open problems. 73 references

  7. Hydropower Projects

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-04-02

    The Water Power Program helps industry harness this renewable, emissions-free resource to generate environmentally sustainable and cost-effective electricity. Through support for public, private, and nonprofit efforts, the Water Power Program promotes the development, demonstration, and deployment of advanced hydropower devices and pumped storage hydropower applications. These technologies help capture energy stored by diversionary structures, increase the efficiency of hydroelectric generation, and use excess grid energy to replenish storage reserves for use during periods of peak electricity demand. In addition, the Water Power Program works to assess the potential extractable energy from domestic water resources to assist industry and government in planning for our nation’s energy future. From FY 2008 to FY 2014, DOE’s Water Power Program announced awards totaling approximately $62.5 million to 33 projects focused on hydropower. Table 1 provides a brief description of these projects.

  8. Project Prometheus

    Science.gov (United States)

    Johnson, Steve

    2003-01-01

    Project Prometheus will enable a new paradigm in the scientific exploration of the Solar System. The proposed JIMO mission will start a new generation of missions characterized by more maneuverability, flexibility, power and lifetime. Project Prometheus organization is established at NASA Headquarters: 1.Organization established to carry out development of JIMO, nuclear power (radioisotope), and nuclear propulsion research. 2.Completed broad technology and national capacity assessments to inform decision making on planning and technology development. 3.Awarded five NRA s for nuclear propulsion research. 4.Radioisotope power systems in development, and Plutonium-238 being purchased from Russia. 5.Formulated science driven near-term and long-term plan for the safe utilization of nuclear propulsion based missions. 6.Completed preliminary studies (Pre-Phase A) of JIMO and other missions. 7.Initiated JIMO Phase A studies by Contractors and NASA.

  9. PARTNER Project

    CERN Document Server

    Ballantine, A; Dixon-Altaber, H; Dosanjh, M; Kuchina, L

    2011-01-01

    Hadrontherapy uses particle beams to treat tumours located near critical organs and tumours that respond poorly to conventional radiation therapy. It has become evident that there is an emerging need for reinforcing research in hadrontherapy and it is essential to train professionals in this rapidly developing field. PARTNER is a 4-year Marie Curie Training project funded by the European Commission with 5.6 million Euros aimed at the creation of the next generation of experts. Ten academic institutes and research centres and two leading companies are participating in PARTNER, that is coordinated by CERN, forming a unique multidisciplinary and multinational European network. The project offers research and training opportunities to 25 young biologists, engineers, physicians and physicists and is allowing them to actively develop modern techniques for treating cancer in close collaboration with leading European Institutions. For this purpose PARTNER relies on cutting edge research and technology development, ef...

  10. Project Radon

    International Nuclear Information System (INIS)

    Ekholm, S.

    1988-01-01

    The project started in March 1987. The objective is to perform radon monitoring in 2000 dwellings occupied by people employed by State Power Board and to continue to contribute to the development of radon filters. The project participates in developing methods for radon measurement and decontamination and in adapting the methods to large scale application. About 400 so called radon trace measurements (coarse measurement) and about 10 action measurements (decontamination measurement) have been made so far. Experience shows that methods are fully applicable and that the decontamination measures recommended give perfectly satisfactory results. It is also established that most of the houses with high radon levels have poor ventilation Many of them suffer from moisture and mould problems. The work planned for 1988 and 1989 will in addition to measurements be directed towards improvement of the measuring methods. An activity catalogue will be prepared in cooperation with ventilation enterprises. (O.S.)

  11. Spent Nuclear Fuel project, project management plan

    International Nuclear Information System (INIS)

    Fuquay, B.J.

    1995-01-01

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  12. Project Phaseolus

    International Nuclear Information System (INIS)

    Anon.

    Research carried out through the Phaseolus Project of the 'Centro de Energia Nuclear na Agricultura' (CENA) Piracicaba, Sao Paulo State, Brazil, is described. It comprises the following subject s: plant breeding; nitrogen fixation; tissue cultures; proteins; photosynthetic efficiency; soil-plant interactions; electron microscopy of the golden mosaic virus; pest control; production of 15 N-enriched ammonium sulfate, and determination of elements in the beans plant. (M.A.) [pt

  13. ARTIST Project

    CSIR Research Space (South Africa)

    Ferguson, K

    2012-10-01

    Full Text Available Biennial Conference Presented by: Keith Ferguson Date: 9 October 2012 Mobile IPTV Broadcasting Platform Consortium: CSIR, UCT, ECA Funded by TIA 2008-2011 ARTIST Project Min time - sacrifice quality Max quality - sacrifice time Application Context... delay tolerance network dependency file download and play file streaming live broadcast peer to peer Online Video Shop e.g. Netflix Video-On-Demand e.g. YouTube Videoconferencing e.g. Skype ARTIST ? Adaptive Real-Time Internet Streaming...

  14. CARA project

    International Nuclear Information System (INIS)

    Bergallo, Juan E.; Brasnarof, Daniel O.

    2000-01-01

    The CARA (Advanced Fuels for Argentine Reactors) Project successfully completed its first stage, phase one, last year. The performance of this fuel has been partially examined, using CNEA and CONUAR facilities and personnel. With the results obtained in this stage, determined by the corresponding tests and verification of the fuel behavior, the performance of the second stage started immediately afterwards. Works performed and results obtained during the development of the second stage are generally described in this paper. (author)

  15. SU-F-I-08: CT Image Ring Artifact Reduction Based On Prior Image

    International Nuclear Information System (INIS)

    Yuan, C; Qi, H; Chen, Z; Wu, S; Xu, Y; Zhou, L

    2016-01-01

    Purpose: In computed tomography (CT) system, CT images with ring artifacts will be reconstructed when some adjacent bins of detector don’t work. The ring artifacts severely degrade CT image quality. We present a useful CT ring artifacts reduction based on projection data correction, aiming at estimating the missing data of projection data accurately, thus removing the ring artifacts of CT images. Methods: The method consists of ten steps: 1) Identification of abnormal pixel line in projection sinogram; 2) Linear interpolation within the pixel line of projection sinogram; 3) FBP reconstruction using interpolated projection data; 4) Filtering FBP image using mean filter; 5) Forwarding projection of filtered FBP image; 6) Subtraction forwarded projection from original projection; 7) Linear interpolation of abnormal pixel line area in the subtraction projection; 8) Adding the interpolated subtraction projection on the forwarded projection; 9) FBP reconstruction using corrected projection data; 10) Return to step 4 until the pre-set iteration number is reached. The method is validated on simulated and real data to restore missing projection data and reconstruct ring artifact-free CT images. Results: We have studied impact of amount of dead bins of CT detector on the accuracy of missing data estimation in projection sinogram. For the simulated case with a resolution of 256 by 256 Shepp-Logan phantom, three iterations are sufficient to restore projection data and reconstruct ring artifact-free images when the dead bins rating is under 30%. The dead-bin-induced artifacts are substantially reduced. More iteration number is needed to reconstruct satisfactory images while the rating of dead bins increases. Similar results were found for a real head phantom case. Conclusion: A practical CT image ring artifact correction scheme based on projection data is developed. This method can produce ring artifact-free CT images feasibly and effectively.

  16. SUPERSITE PROJECT

    Directory of Open Access Journals (Sweden)

    Silvia Ferrari

    2010-04-01

    Full Text Available The project is focused on a detailed study of some chemical, physical and toxicological parameters and on health, epidemiological and environmental assessment by interpretative models, in the atmosphere of Emilia-Romagna (Italy. The project rises from the necessity to improve  knowledge about environmental and health aspects of fine and ultrafine particles, in primary and secondary components, in the atmosphere. The project, structured in 7 workpackages, is organized in two measurement programmes: the routine one that has a mainly daily time resolution, and the intensive one with high time resolution and a higher chemical speciation than the routine one. The sampling sites are five: three in urban areas (Bologna, Parma and Rimini, one in a rural area (San Pietro Capofiume and one in a remote area (Monte Cimone. Parallel to outdoor studies, a workpackage  is planned for indoor studies and chemical composition analysis with the  outdoor/indoor ratio for characterizing indoor human exposure to outdoor pollution.

  17. Aspects of optical and digital processing of scintigraphic images

    International Nuclear Information System (INIS)

    Platzer, H.; Wahl, F.; Hofer, J.; Galosi, H.; Langhammer, H.

    1981-01-01

    The Anger camera, which is able to represent three-dimensional radioactivity distributions as two-dimensional projections, has become a standard tool in diagnostic nuclear medicine. The two-dimensional projections are reviewed under the aspects of imaging and image processing. Coherent optical image processing and digital image processing are discussed in particular. (WU) [de

  18. Coloss project

    International Nuclear Information System (INIS)

    2005-01-01

    The COLOSS project was a shared-cost action, co-ordinated by IRSN within the Euratom Research Framework Programme 1998-2002. Started in February 2000, the project lasted three years. The work-programme performed by 19 partners was shaped around complementary activities aimed at improving severe accident codes. Unresolved risk-relevant issues regarding H2 production, melt generation and the source term were studied, through a large number of experiments such as a) dissolution of fresh and high burn-up UO 2 and MOX by molten Zircaloy, b) simultaneous dissolution of UO 2 and ZrO 2 by molten Zircaloy, c) oxidation of U-O-Zr mixtures by steam, d) degradation-oxidation of B 4 C control rods. Significant results have been produced from separate-effects, semi-global and large-scale tests on COLOSS topics. Break-through were achieved on some issues. Nevertheless, more data are needed for consolidation of the modelling on burn-up effects on UO 2 and MOX dissolution and on oxidation of U-O-Zr and B 4 C-metal mixtures. There was experimental evidence that the oxidation of these mixtures can contribute significantly to the large H2 production observed during the reflooding of degraded cores under severe accident conditions. Based on the experimental results obtained on the COLOSS topics, corresponding models were developed and were successfully implemented in several severe accident codes. Upgraded codes were then used for plant calculations to evaluate the consequences of new models on key severe accident sequences occurring in different plants designs involving B 4 C control rods (EPR, BWR, VVER- 1000) as well as in the TMI-2 accident. The large series of plant calculations involved sensitivity studies and code benchmarks. Main severe accident codes in use in the EU for safety studies were used such as ICARE/CATHARE, SCDAP/RELAP5, ASTEC, MELCOR and MAAP4. This activity enabled: a) the assessment of codes to calculate core degradation, b) the identification of main

  19. Image forming apparatus

    DEFF Research Database (Denmark)

    2005-01-01

    An image H(x, y) for displaying a target image G(x, y) is displayed on a liquid-crystal display panel and illumination light from an illumination light source is made to pass therethrough to form an image on a PALSLM. Read light hv is radiated to the PALSLM and a phase-modulated light image alpha...... (x, y) read out of the PALSLM is subjected to Fourier transform by a lens. A phase contrast filter gives a predetermined phase shift to only the zero-order light component of Fourier light image alpha f(x, y). The phase-shifted light image is subjected to inverse Fourier transform by a lens...... to project an output image O(x, y) to an output plane. A light image O'(x, y) branched by a beam sampler is picked up by a pickup device and an evaluation value calculating unit evaluates conformity between the image O(x, y) and the image G(x, y).; A control unit performs feedback control of optical...

  20. Imaging shoulder impingement

    Energy Technology Data Exchange (ETDEWEB)

    Gold, R.H. (Dept. of Radiological Sciences, UCLA School of Medicine, Los Angeles, CA (United States)); Seeger, L.L. (Dept. of Radiological Sciences, UCLA School of Medicine, Los Angeles, CA (United States)); Yao, L. (Dept. of Radiological Sciences, UCLA School of Medicine, Los Angeles, CA (United States))

    1993-11-01

    Appropriate imaging and clinical examinations may lead to early diagnosis and treatment of the shoulder impingement syndrome, thus preventing progression to a complete tear of the rotator cuff. In this article, we discuss the anatomic and pathophysiologic bases of the syndrome, and the rationale for certain imaging tests to evaluate it. Special radiographic projections to show the supraspinatus outlet and inferior surface of the anterior third of the acromion, combined with magnetic resonance images, usually provide the most useful information regarding the causes of impingement. (orig.)

  1. Imaging shoulder impingement

    International Nuclear Information System (INIS)

    Gold, R.H.; Seeger, L.L.; Yao, L.

    1993-01-01

    Appropriate imaging and clinical examinations may lead to early diagnosis and treatment of the shoulder impingement syndrome, thus preventing progression to a complete tear of the rotator cuff. In this article, we discuss the anatomic and pathophysiologic bases of the syndrome, and the rationale for certain imaging tests to evaluate it. Special radiographic projections to show the supraspinatus outlet and inferior surface of the anterior third of the acromion, combined with magnetic resonance images, usually provide the most useful information regarding the causes of impingement. (orig.)

  2. Demonstration projects

    International Nuclear Information System (INIS)

    Robertson, R.F.S.

    1976-01-01

    A discussion of some of the projects in Canada planned to demonstrate the technical and economic feasibility of processes using waste heat. Most of the studies are in the planning stage; few field demonstrations are yet in operation in any of the three arbitrary categories of waste heat - high-grade heat (100-200 deg C), medium-grade heat (30-100 deg C), and low-grade heat (below 30 deg C). The survey indicates that, while there is long-term potential in several of the approaches, the time has arrived to start finding some hard facts. (author)

  3. Projective mapping

    DEFF Research Database (Denmark)

    Dehlholm, Christian; Brockhoff, Per B.; Bredie, Wender Laurentius Petrus

    2012-01-01

    the applied framework, semantic restrictions, the choice of type of assessors and the validation of product separations. The applied framework concerns the response surface as presented to the assessor in different shapes, e.g. rectangular, square or round. Semantic restrictions are a part of the assessor...... instructions and influence heavily the product placements and the descriptive vocabulary (Dehlholm et.al., 2012b). The type of assessors performing the method influences results with an extra aspect in Projective Mapping compared to more analytical tests, as the given spontaneous perceptions are much dependent...

  4. Project Exodus

    Science.gov (United States)

    1990-01-01

    Project Exodus is an in-depth study to identify and address the basic problems of a manned mission to Mars. The most important problems concern propulsion, life support, structure, trajectory, and finance. Exodus will employ a passenger ship, cargo ship, and landing craft for the journey to Mars. These three major components of the mission design are discussed separately. Within each component the design characteristics of structures, trajectory, and propulsion are addressed. The design characteristics of life support are mentioned only in those sections requiring it.

  5. Virtual reality for simulation of radiographic projections: validation of projection geometry.

    Science.gov (United States)

    Nilsson, T; Ahlqvist, J; Johansson, M; Isberg, A

    2004-01-01

    To develop a software for virtual reality (VR) simulation of X-ray images based on perspective projections through a patient model derived from data from a CT examination and to evaluate the accuracy in the projection geometry obtained by the software. A VR software was developed on a personal computer, with models of a patient, an X-ray machine and a detector. The model of the patient was derived from data from a CT examination of a dry skull. Simulated radiographic images of the patient model could be rendered as perspective projections based on the relative positions between the models. The projection geometry of the software was validated by developing an artificial CT data set containing high attenuation points as objects to be imaged. The accuracy in projection geometry was evaluated in a systematic way. The distances between two dots, representing the projected test points in the simulated radiographic images, were measured. They were compared with theoretical calculations of the corresponding distances using traditional mathematical tools. The difference between the simulated and calculated projected distances never exceeded 0.5 mm. The error in simulated projected distances was in most cases within 1%. No systematic errors were revealed. The software, developed for personal computers, can produce simulated X-ray images with high geometric accuracy based on perspective projections through a CT data set. The software can be used for simulation of radiographic examinations.

  6. IMAGE ACQUISITION CONSTRAINTS FOR PANORAMIC FRAME CAMERA IMAGING

    Directory of Open Access Journals (Sweden)

    H. Kauhanen

    2012-07-01

    Full Text Available The paper describes an approach to quantify the amount of projective error produced by an offset of projection centres in a panoramic imaging workflow. We have limited this research to such panoramic workflows in which several sub-images using planar image sensor are taken and then stitched together as a large panoramic image mosaic. The aim is to simulate how large the offset can be before it introduces significant error to the dataset. The method uses geometrical analysis to calculate the error in various cases. Constraints for shooting distance, focal length and the depth of the area of interest are taken into account. Considering these constraints, it is possible to safely use even poorly calibrated panoramic camera rig with noticeable offset in projection centre locations. The aim is to create datasets suited for photogrammetric reconstruction. Similar constraints can be used also for finding recommended areas from the image planes for automatic feature matching and thus improve stitching of sub-images into full panoramic mosaics. The results are mainly designed to be used with long focal length cameras where the offset of projection centre of sub-images can seem to be significant but on the other hand the shooting distance is also long. We show that in such situations the error introduced by the offset of the projection centres results only in negligible error when stitching a metric panorama. Even if the main use of the results is with cameras of long focal length, they are feasible for all focal lengths.

  7. PORTNUS Project

    Energy Technology Data Exchange (ETDEWEB)

    Loyal, Rebecca E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-07-14

    The objective of the Portunus Project is to create large, automated offshore ports that will the pace and scale of international trade. Additionally, these ports would increase the number of U.S. domestic trade vessels needed, as the imported goods would need to be transported from these offshore platforms to land-based ports such as Boston, Los Angeles, and Newark. Currently, domestic trade in the United States can only be conducted by vessels that abide by the Merchant Marine Act of 1920 – also referred to as the Jones Act. The Jones Act stipulates that vessels involved in domestic trade must be U.S. owned, U.S. built, and manned by a crew made up of U.S. citizens. The Portunus Project would increase the number of Jones Act vessels needed, which raises an interesting economic concern. Are Jones Act ships more expensive to operate than foreign vessels? Would it be more economically efficient to modify the Jones Act and allow vessels manned by foreign crews to engage in U.S. domestic trade? While opposition to altering the Jones Act is strong, it is important to consider the possibility that ship-owners who employ foreign crews will lobby for the chance to enter a growing domestic trade market. Their success would mean potential job loss for thousands of Americans currently employed in maritime trade.

  8. FLORAM project

    Energy Technology Data Exchange (ETDEWEB)

    Zulauf, W.E. [Sao Paolos Environmental Secretariat, Sao Paolo (Brazil); Goelho, A.S.R. [Riocell, S.A. (Brazil); Saber, A. [IEA-Instituto de Estudos Avancados (Brazil)] [and others

    1995-12-31

    The project FLORAM was formulated at the `Institute for Advanced Studies` of the University of Sao Paulo. It aims at decreasing the level of carbon dioxide in the atmosphere and thus curbing the green-house effect by way of a huge effort of forestation and reforestation. The resulting forests when the trees mature, will be responsible for the absorption of about 6 billion tons of excess carbon. It represents 5 % of the total amount of CO{sub 2} which is in excess in the earth`s atmosphere and represents 5 % of the available continental surfaces which can be forested as well. Therefore, if similar projects are implemented throughout the world, in theory all the exceeding CO{sub 2}, responsible for the `greenhouse effect`, (27 % or 115 billion tons of carbon) would be absorbed. Regarding this fact, there would be a 400 million hectar increase of growing forests. FLORAM in Brazil aims to plant 20.000.000 ha in 2 years at a cost of 20 billion dollars. If it reaches its goals that will mean that Brazil will have reforested an area almost half as big as France. (author)

  9. Computers in Public Schools: Changing the Image with Image Processing.

    Science.gov (United States)

    Raphael, Jacqueline; Greenberg, Richard

    1995-01-01

    The kinds of educational technologies selected can make the difference between uninspired, rote computer use and challenging learning experiences. University of Arizona's Image Processing for Teaching Project has worked with over 1,000 teachers to develop image-processing techniques that provide students with exciting, open-ended opportunities for…

  10. Portable Ultrasound Imaging

    DEFF Research Database (Denmark)

    di Ianni, Tommaso

    This PhD project investigates hardware strategies and imaging methods for hand-held ultrasound systems. The overall idea is to use a wireless ultrasound probe linked to general-purpose mobile devices for the processing and visualization. The approach has the potential to reduce the upfront costs ...

  11. Images of Women

    DEFF Research Database (Denmark)

    Anderberg, Birgitte

    2016-01-01

    Images of Women, which took place in Copenhagen in March 1970, at the same time as the first political interventions of the feminist movement, the "Redstockings", was the first feminist art exhibition in Scandinavia. The essay analyses the content of this collaborative project and demonstrates ho...

  12. Unsupervised Image Segmentation

    Czech Academy of Sciences Publication Activity Database

    Haindl, Michal; Mikeš, Stanislav

    2014-01-01

    Roč. 36, č. 4 (2014), s. 23-23 R&D Projects: GA ČR(CZ) GA14-10911S Institutional support: RVO:67985556 Keywords : unsupervised image segmentation Subject RIV: BD - Theory of Information http:// library .utia.cas.cz/separaty/2014/RO/haindl-0434412.pdf

  13. Electron Paramagnetic Resonance Imaging

    Indian Academy of Sciences (India)

    IAS Admin

    MRI deals with the in vivo distribution of endogenous protons in water and tissue, whereas for EPRI we have to introduce bio- compatible free radicals before imaging. ..... no spectral information, but only spatial information. We can understand the spectral–spatial projections if we define a pseudo- viewing angle defined by.

  14. Fast Plane Wave Imaging

    DEFF Research Database (Denmark)

    Jensen, Jonas

    This PhD project investigates and further develops methods for ultrasound plane wave imaging and blood flow estimation with the objective of overcoming some of the major limitations in conventional ultrasound systems, which are related to low frame rates and only estimation of velocities along th...

  15. An image scanner for real time analysis of spark chamber images

    International Nuclear Information System (INIS)

    Cesaroni, F.; Penso, G.; Locci, A.M.; Spano, M.A.

    1975-01-01

    The notes describes the semiautomatic scanning system at LNF for the analysis of spark chamber images. From the projection of the images on the scanner table, the trajectory in the real space is reconstructed

  16. Project: Ultracentrifuges

    International Nuclear Information System (INIS)

    Olea C, O.

    1990-07-01

    The trans elastic ultracentrifuge of magnetic suspension, is an instrument that arose of an interdisciplinary group directed by the Dr. James Clark Keith where it was projected, designed and built a centrifuge that didn't exist, to be applied in forced diffusion of uranium, like one of the many application fields. The written present, has as purpose to give to know the fundamental physical principles of this technology, its fundamental characteristics of design, the application of this in the separation process of isotopes, as well as the previous studies and essential control parameters in the experimental processes, the same thing that, the most outstanding results and the detection systems used in the confirmation and finally, the carried out potential applications of the principles of the ultracentrifugation technology. (Author)

  17. EUROTRAC projects

    International Nuclear Information System (INIS)

    Slanina, J.; Arends, B.G.; Wyers, G.P.

    1992-07-01

    The projects discussed are BIATEX (BIosphere-ATmosphere EXchange of pollutants), ACE (Acidity in Clouds Experiment) and GCE (Ground-based Cloud Experiment). ECN also coordinates BIATEX and contributes to the coordination of EUROTRAC. Research in BIATEX is aimed at the development of equipment, by which atmosphere-surface interactions of air pollution can be quantified. A ion chromatograph, connected to a rotating denuder, is developed to be applicated in the field for on-line analysis of denuder extracts and other samples. To investigate dry deposition of ammonia a continuous-flow denuder has been developed. A thermodenuder system to measure the concentrations of HNO 3 and NH 4 NO 3 in the ambient air is optimized to determine depositions and is part of the ECN monitoring station in Zegveld, Netherlands. An aerosol separation technique, based on a cyclone separator, has also been developed. All this equipment has been used in field experiments above wheat and heather. An automated monitoring station for long-term investigations of NH 3 , HNO 3 and SO 2 dry deposition on grassland and the impact of the deposition on the presence and composition of water films has been set up and fully tested. Research in GCE concerns the uptake and conversion of air pollution in clouds (cloud chemistry). Measuring equipment from several collaborative institutes has been specified and calibrated in a cloud chamber at ECN. The ECN contribution is the determination of the gas phase composition and the micro-physical characterization of the clouds. Measurement campaigns were carried out in the Po area (Italy) in fog, and in Kleiner Feldberg near Frankfurt, Germany, in orographic clouds. Estimations are given of the deposition of fog water and cloud water on forests in the Netherlands and the low mountain range in Germany. The project ACE was not started because of financial reasons and will be reconsidered. 26 figs., 1 tab., 3 apps., 34 refs

  18. Data imaging

    International Nuclear Information System (INIS)

    Pepy, G.

    1999-01-01

    After an introduction about data imaging in general, the principles of imaging data collected via neutron scattering experiments are presented. Some computer programs designed for data imaging purposes are reviewed. (K.A.)

  19. Tomographic imaging

    International Nuclear Information System (INIS)

    Newman, M.A.

    1989-01-01

    Tomographic images of an object or scene are produced by an analysis of two or more stereographic images of the scene including shifting one image laterally with respect to another and logically summing the image data sets. Several image processing, edge enhancement and edge extraction algorithms may be applied to the images in digitised video data form to provide wire-frame or skeleton type representations of each of the original images. Tomographic images of planes not parallel with the image plane (or normal to the camera axes) may be produced by changing the magnification of one image prior to logical summing. The images may be generated by three video cameras arranged on two orthogonal axes for elimination of spurious coincidences. The images are preferably produced using X-rays. (author)

  20. Image Statistics

    Energy Technology Data Exchange (ETDEWEB)

    Wendelberger, Laura Jean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-08-08

    In large datasets, it is time consuming or even impossible to pick out interesting images. Our proposed solution is to find statistics to quantify the information in each image and use those to identify and pick out images of interest.

  1. Project Success in IT Project Management

    OpenAIRE

    Siddiqui, Farhan Ahmed

    2010-01-01

    The rate of failed and challenged Information Technology (IT) projects is too high according to the CHAOS Studies by the Standish Group and the literature on project management (Standish Group, 2008). The CHAOS Studies define project success as meeting the triple constraints of scope, time, and cost. The criteria for project success need to be agreed by all parties before the start of the project and constantly reviewed as the project progresses. Assessing critical success factors is another ...

  2. Quantum Imaging

    CERN Document Server

    Kolobov, Mikhail I

    2007-01-01

    Quantum Imaging is a newly born branch of quantum optics that investigates the ultimate performance limits of optical imaging allowed by the laws of quantum mechanics. Using the methods and techniques from quantum optics, quantum imaging addresses the questions of image formation, processing and detection with sensitivity and resolution exceeding the limits of classical imaging. This book contains the most important theoretical and experimental results achieved by the researchers of the Quantum Imaging network, a research programme of the European Community.

  3. ImageX: new and improved image explorer for astronomical images and beyond

    Science.gov (United States)

    Hayashi, Soichi; Gopu, Arvind; Kotulla, Ralf; Young, Michael D.

    2016-08-01

    The One Degree Imager - Portal, Pipeline, and Archive (ODI-PPA) has included the Image Explorer interactive image visualization tool since it went operational. Portal users were able to quickly open up several ODI images within any HTML5 capable web browser, adjust the scaling, apply color maps, and perform other basic image visualization steps typically done on a desktop client like DS9. However, the original design of the Image Explorer required lossless PNG tiles to be generated and stored for all raw and reduced ODI images thereby taking up tens of TB of spinning disk space even though a small fraction of those images were being accessed by portal users at any given time. It also caused significant overhead on the portal web application and the Apache webserver used by ODI-PPA. We found it hard to merge in improvements made to a similar deployment in another project's portal. To address these concerns, we re-architected Image Explorer from scratch and came up with ImageX, a set of microservices that are part of the IU Trident project software suite, with rapid interactive visualization capabilities useful for ODI data and beyond. We generate a full resolution JPEG image for each raw and reduced ODI FITS image before producing a JPG tileset, one that can be rendered using the ImageX frontend code at various locations as appropriate within a web portal (for example: on tabular image listings, views allowing quick perusal of a set of thumbnails or other image sifting activities). The new design has decreased spinning disk requirements, uses AngularJS for the client side Model/View code (instead of depending on backend PHP Model/View/Controller code previously used), OpenSeaDragon to render the tile images, and uses nginx and a lightweight NodeJS application to serve tile images thereby significantly decreasing the Time To First Byte latency by a few orders of magnitude. We plan to extend ImageX for non-FITS images including electron microscopy and radiology scan

  4. FY 2000 Project of developing international standards for supporting new industries. SMIL tag standard of the three-dimensional image data, based on MXL; 2000 nendo shinki sangyo shiengata kokusai hyojun kaihatsu jigyo seika hokokusho. XML wo base to shita rittai eizo data SMIL tag tsuke kikaku no hyojunka

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    This project is aimed at proposals of the standards for utilizing three-dimensional images for multimedia presentation on the Internet. Described herein are the FY 2000 results for proposal of SMIL (synchronized multimedia integration language) tag standard of the three-dimensional image data, based on XML which is the next generation standard of HTML, and research and development of the generated editor of tag data for the three-dimensional images, three-dimensional QuickTimeVR player and three-dimensional MPEG player. The FY 2000 efforts are directed to the examination/proposal of the tags for three-dimensional images which are not defined by the present XML and SMIL, based on which the tag editor is developed. The other efforts include survey on the latest situations around the standards and trends of the Web and three-dimensional data; and development of the player and browser of SMIL tags, both for three-dimensional images. The efforts for the international standardization include preparation of the three-dimensional standard drafts for displaying various media data in the three-dimensional world, which are submitted to the W3C members to sound their opinions, and collection of related information. (NEDO)

  5. Dynamic Underground Stripping Demonstration Project

    International Nuclear Information System (INIS)

    Aines, R.; Newmark, R.; McConachie, W.; Rice, D.; Ramirez, A.; Siegel, W.; Buettner, M.; Daily, W.; Krauter, P.; Folsom, E.; Boegel, A.J.; Bishop, D.; udel, K.

    1992-03-01

    LLNL is collaborating with the UC Berkeley College of Engineering to develop and demonstrate a system of thermal remediation and underground imaging techniques for use in rapid cleanup of localized underground spills. Called ''Dynamic Stripping'' to reflect the rapid and controllable nature of the process, it will combine steam injection, direct electrical heating, and tomographic geophysical imaging in a cleanup of the LLNL gasoline spill. In the first 8 months of the project, a Clean Site engineering test was conducted to prove the field application of the techniques before moving to the contaminated site in FY 92

  6. Project LASER

    Science.gov (United States)

    1990-01-01

    NASA formally launched Project LASER (Learning About Science, Engineering and Research) in March 1990, a program designed to help teachers improve science and mathematics education and to provide 'hands on' experiences. It featured the first LASER Mobile Teacher Resource Center (MTRC), is designed to reach educators all over the nation. NASA hopes to operate several MTRCs with funds provided by private industry. The mobile unit is a 22-ton tractor-trailer stocked with NASA educational publications and outfitted with six work stations. Each work station, which can accommodate two teachers at a time, has a computer providing access to NASA Spacelink. Each also has video recorders and photocopy/photographic equipment for the teacher's use. MTRC is only one of the five major elements within LASER. The others are: a Space Technology Course, to promote integration of space science studies with traditional courses; the Volunteer Databank, in which NASA employees are encouraged to volunteer as tutors, instructors, etc; Mobile Discovery Laboratories that will carry simple laboratory equipment and computers to provide hands-on activities for students and demonstrations of classroom activities for teachers; and the Public Library Science Program which will present library based science and math programs.

  7. Projection computation based on pixel in simultaneous algebraic reconstruction technique

    International Nuclear Information System (INIS)

    Wang Xu; Chen Zhiqiang; Xiong Hua; Zhang Li

    2005-01-01

    SART is an important arithmetic of image reconstruction, in which the projection computation takes over half of the reconstruction time. An efficient way to compute projection coefficient matrix together with memory optimization is presented in this paper. Different from normal method, projection lines are located based on every pixel, and the following projection coefficient computation can make use of the results. Correlation of projection lines and pixels can be used to optimize the computation. (authors)

  8. Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Sensakovic, William F.; O' Dell, M.C.; Letter, Haley; Kohler, Nathan; Rop, Baiywo; Cook, Jane; Logsdon, Gregory; Varich, Laura [Florida Hospital, Imaging Administration, Orlando, FL (United States)

    2016-10-15

    Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA{sup 2} by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 μSv; P < 0.0001). Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image

  9. Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs

    International Nuclear Information System (INIS)

    Sensakovic, William F.; O'Dell, M.C.; Letter, Haley; Kohler, Nathan; Rop, Baiywo; Cook, Jane; Logsdon, Gregory; Varich, Laura

    2016-01-01

    Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA 2 by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 μSv; P < 0.0001). Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image processing

  10. NOAA TIFF Image - 1 m Backscatter Mosaic of the Virgin Passage and the St. John Shelf, U.S. Virgin Islands, Project NF-10-03, 2010, UTM 20 WGS84

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the Virgin Passage in the US Virgin Islands. NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  11. NOAA TIFF Image- 0.5 meter Backscatter Mosaic of Mid Shelf Reef (St. Thomas), US Virgin Islands, Project NF-05-05, 2005, UTM 20 NAD83 (NCEI Accession 0131860)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.5 meter resolution backscatter mosaic of the Mid Shelf Reef south of St. Thomas, US Virgin IslandsNOAA's NOS/NCCOS/CCMA Biogeography Team,...

  12. NOAA TIFF Image- 0.5 meter Backscatter Mosaic of Grammanik Bank - East (St. Thomas), US Virgin Islands, Project NF-05-05, 2005, UTM 20 NAD83 (NCEI Accession 0131860)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.5 meter resolution backscatter mosaic of Grammanik Bank, south of St. Thomas, US Virgin Islands.NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  13. NOAA TIFF Image - 1 m Backscatter Mosaic of an inshore portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US Virgin Islands, Project NF-05-05, 2005, UTM 20 WGS84 (NCEI Accession 0131860)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the inshore portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US...

  14. NOAA TIFF Image - 1 m Backscatter Mosaic of the Virgin Passage and the St. John Shelf, U.S. Virgin Islands, Project NF-10-03, 2010, UTM 20 WGS84 (NCEI Accession 0131854)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the Virgin Passage in the US Virgin Islands. NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  15. NOAA TIFF Image - 3 m Backscatter Mosaic of the north shore of St. Croix, U.S. Virgin Islands, Project NF-06-03, 2006, UTM 20 WGS84

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 3 meter resolution backscatter mosaic of the north shore of St. Croix, US Virgin Islands. NOAA's NOS/NCCOS/CCMA Biogeography Team, in...

  16. NOAA TIFF Image - 1 m Backscatter Mosaic of the St. John Shelf, U.S. Virgin Islands, Project NF-10-03, 2010, UTM 20 WGS84 (NCEI Accession 0131854)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the St. John Shelf, US Virgin Islands. NOAA's NOS/NCCOS/CCMA Biogeography Team, in collaboration...

  17. NOAA TIFF Image - 1 m Backscatter Mosaic of an offshore portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US Virgin Islands, Project NF-05-05, 2005, UTM 20 WGS84 (NCEI Accession 0131860)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of an offshore portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US...

  18. NOAA TIFF Image - 1 m Backscatter Mosaic of an inshore portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US Virgin Islands, Project NF-05-05, 2005, UTM 20 WGS84

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the inshore portion of the NPS's Virgin Islands Coral Reef National Monument, south of St. John, US...

  19. Phase Contrast Imaging

    International Nuclear Information System (INIS)

    Menk, Ralf Hendrik

    2008-01-01

    All standard (medical) x-ray imaging technologies, rely primarily on the amplitude properties of the incident radiation, and do not depend on its phase. This is unchanged since the discovery by Roentgen that the intensity of an x-ray beam, as measured by the exposure on a film, was related to the relative transmission properties of an object. However, recently various imaging techniques have emerged which depend on the phase of the x-rays as well as the amplitude. Phase becomes important when the beam is coherent and the imaging system is sensitive to interference phenomena. Significant new advances have been made in coherent optic theory and techniques, which now promise phase information in medical imaging. The development of perfect crystal optics and the increasing availability of synchrotron radiation facilities have contributed to a significant increase in the application of phase based imaging in materials and life sciences. Unique source characteristics such as high intensity, monochromaticity, coherence and high collimating provide an ideal source for advanced imaging. Phase contrast imaging has been applied in both projection and computed tomography modes, and recent applications have been made in the field of medical imaging. Due to the underlying principle of X-ray detection conventional image receptors register only intensities of wave fields and not their phases. During the last decade basically five different methods were developed that translate the phase information into intensity variations. These methods are based on measuring the phase shift φ directly (using interference phenomena), the gradient ∇ φ , or the Laplacian ∇ 2 φ. All three methods can be applied to polychromatic X-ray sources keeping in mind that the native source is synchrotron radiation, featuring monochromatic and reasonable coherent X-ray beams. Due to the vast difference in the coefficients that are driven absorption and phase effects (factor 1,000-10,000 in the energy

  20. Ace Project as a Project Management Tool

    Science.gov (United States)

    Cline, Melinda; Guynes, Carl S.; Simard, Karine

    2010-01-01

    The primary challenge of project management is to achieve the project goals and objectives while adhering to project constraints--usually scope, quality, time and budget. The secondary challenge is to optimize the allocation and integration of resources necessary to meet pre-defined objectives. Project management software provides an active…