WorldWideScience

Sample records for surface projection images

  1. 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.

  2. 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...

  3. The Stellar Imager (SI) Project: Resolving Stellar Surfaces, Interiors, and Magnetic Activity

    Science.gov (United States)

    Carpenter, Kenneth G.; Schrijver, K.; Karovska, M.

    2007-01-01

    The Stellar Imager (SI) is a UV/Optical. Space-Based Interferometer designed to enable 0.1 milli-arcsec (mas) spectral imaging of stellar surfaces and, via asteroseismology, stellar interiors and of the Universe in general. The ultra-sharp images of SI will revolutionize our view of many dynamic astrophysical processes by transforming point sources into extended sources, and snapshots into evolving views. The science of SI focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. Its prime goal is to enable long-term forecasting of solar activity and the space weather that it drives. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in the Universe. In this paper we discuss the science goals, technology needs, and baseline design of the SI mission.

  4. 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.

  5. GOATS Image Projection Component

    Science.gov (United States)

    Haber, Benjamin M.; Green, Joseph J.

    2011-01-01

    When doing mission analysis and design of an imaging system in orbit around the Earth, answering the fundamental question of imaging performance requires an understanding of the image products that will be produced by the imaging system. GOATS software represents a series of MATLAB functions to provide for geometric image projections. Unique features of the software include function modularity, a standard MATLAB interface, easy-to-understand first-principles-based analysis, and the ability to perform geometric image projections of framing type imaging systems. The software modules are created for maximum analysis utility, and can all be used independently for many varied analysis tasks, or used in conjunction with other orbit analysis tools.

  6. Nonlaser-based 3D surface imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shin-yee; Johnson, R.K.; Sherwood, R.J. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    3D surface imaging refers to methods that generate a 3D surface representation of objects of a scene under viewing. Laser-based 3D surface imaging systems are commonly used in manufacturing, robotics and biomedical research. Although laser-based systems provide satisfactory solutions for most applications, there are situations where non laser-based approaches are preferred. The issues that make alternative methods sometimes more attractive are: (1) real-time data capturing, (2) eye-safety, (3) portability, and (4) work distance. The focus of this presentation is on generating a 3D surface from multiple 2D projected images using CCD cameras, without a laser light source. Two methods are presented: stereo vision and depth-from-focus. Their applications are described.

  7. Fluorescence Imaging Reveals Surface Contamination

    Science.gov (United States)

    Schirato, Richard; Polichar, Raulf

    1992-01-01

    In technique to detect surface contamination, object inspected illuminated by ultraviolet light to make contaminants fluoresce; low-light-level video camera views fluorescence. Image-processing techniques quantify distribution of contaminants. If fluorescence of material expected to contaminate surface is not intense, tagged with low concentration of dye.

  8. 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...

  9. Uranium Mill Tailings Remedial Action Project surface project management plan

    International Nuclear Information System (INIS)

    1994-09-01

    This Project Management Plan describes the planning, systems, and organization that shall be used to manage the Uranium Mill Tailings Remedial Action Project (UMTRA). US DOE is authorized to stabilize and control surface tailings and ground water contamination at 24 inactive uranium processing sites and associated vicinity properties containing uranium mill tailings and related residual radioactive materials

  10. Photoacoustic projection imaging using an all-optical detector array

    Science.gov (United States)

    Bauer-Marschallinger, J.; Felbermayer, K.; Berer, T.

    2018-02-01

    We present a prototype for all-optical photoacoustic projection imaging. By generating projection images, photoacoustic information of large volumes can be retrieved with less effort compared to common photoacoustic computed tomography where many detectors and/or multiple measurements are required. In our approach, an array of 60 integrating line detectors is used to acquire photoacoustic waves. The line detector array consists of fiber-optic MachZehnder interferometers, distributed on a cylindrical surface. From the measured variation of the optical path lengths of the interferometers, induced by photoacoustic waves, a photoacoustic projection image can be reconstructed. The resulting images represent the projection of the three-dimensional spatial light absorbance within the imaged object onto a two-dimensional plane, perpendicular to the line detector array. The fiber-optic detectors achieve a noise-equivalent pressure of 24 Pascal at a 10 MHz bandwidth. We present the operational principle, the structure of the array, and resulting images. The system can acquire high-resolution projection images of large volumes within a short period of time. Imaging large volumes at high frame rates facilitates monitoring of dynamic processes.

  11. MR imaging of brain surface structures: Surface anatomy scanning

    International Nuclear Information System (INIS)

    Katada, K.; Koga, S.; Asahina, M.; Kanno, T.; Asahina, K.

    1987-01-01

    Preoperative evaluation of brain surface anatomy, including cortical sulci and veins, relative to cerebral and cerebellar lesions is an important subject for surgeons. Until now, no imaging modality existed that allowed direct visualization of brain surface anatomy. A new MR imaging technique (surface anatomy scanning) was developed to visualize brain surface structures. The technique uses a spin-echo pulse sequence with long repetition and echo times, thick sections and a surface coil. Cortical sulci, fissures, veins, and intracranial lesions were clearly identified with this technique. Initial clinical results indicate that surface anatomy scanning is useful for lesion localization and for detailed evaluation of cortical and subcortical lesions

  12. Whole surface image reconstruction for machine vision inspection of fruit

    Science.gov (United States)

    Reese, D. Y.; Lefcourt, A. M.; Kim, M. S.; Lo, Y. M.

    2007-09-01

    Automated imaging systems offer the potential to inspect the quality and safety of fruits and vegetables consumed by the public. Current automated inspection systems allow fruit such as apples to be sorted for quality issues including color and size by looking at a portion of the surface of each fruit. However, to inspect for defects and contamination, the whole surface of each fruit must be imaged. The goal of this project was to develop an effective and economical method for whole surface imaging of apples using mirrors and a single camera. Challenges include mapping the concave stem and calyx regions. To allow the entire surface of an apple to be imaged, apples were suspended or rolled above the mirrors using two parallel music wires. A camera above the apples captured 90 images per sec (640 by 480 pixels). Single or multiple flat or concave mirrors were mounted around the apple in various configurations to maximize surface imaging. Data suggest that the use of two flat mirrors provides inadequate coverage of a fruit but using two parabolic concave mirrors allows the entire surface to be mapped. Parabolic concave mirrors magnify images, which results in greater pixel resolution and reduced distortion. This result suggests that a single camera with two parabolic concave mirrors can be a cost-effective method for whole surface imaging.

  13. Discriminative Projection Selection Based Face Image Hashing

    Science.gov (United States)

    Karabat, Cagatay; Erdogan, Hakan

    Face image hashing is an emerging method used in biometric verification systems. In this paper, we propose a novel face image hashing method based on a new technique called discriminative projection selection. We apply the Fisher criterion for selecting the rows of a random projection matrix in a user-dependent fashion. Moreover, another contribution of this paper is to employ a bimodal Gaussian mixture model at the quantization step. Our simulation results on three different databases demonstrate that the proposed method has superior performance in comparison to previously proposed random projection based methods.

  14. Color correction of projected image on color-screen for mobile beam-projector

    Science.gov (United States)

    Son, Chang-Hwan; Sung, Soo-Jin; Ha, Yeong-Ho

    2008-01-01

    With the current trend of digital convergence in mobile phones, mobile manufacturers are researching how to develop a mobile beam-projector to cope with the limitations of a small screen size and to offer a better feeling of movement while watching movies or satellite broadcasting. However, mobile beam-projectors may project an image on arbitrary surfaces, such as a colored wall and paper, not on a white screen mainly used in an office environment. Thus, color correction method for the projected image is proposed to achieve good image quality irrespective of the surface colors. Initially, luminance values of original image transformed into the YCbCr space are changed to compensate for spatially nonuniform luminance distribution of arbitrary surface, depending on the pixel values of surface image captured by mobile camera. Next, the chromaticity values for each surface and white-screen image are calculated using the ratio of the sum of three RGB values to one another. Then their chromaticity ratios are multiplied by converted original image through an inverse YCbCr matrix to reduce an influence of modulating the appearance of projected image due to spatially different reflectance on the surface. By projecting corrected original image on a texture pattern or single color surface, the image quality of projected image can be improved more, as well as that of projected image on white screen.

  15. An inflatable surface coil for rectal imaging

    International Nuclear Information System (INIS)

    Martin, J.F.; Hajek, P.C.; Baker, L.L.; Gylys-Morin, V.; Mattrey, R.F.

    1986-01-01

    Surface coils have become ubiquitous in MR imaging of the body because of substantial gains in signal-to-noise ratio. Unfortunately, there are some anatomic regions, such as the prostate, for which surface coils have insufficient depth sensitivity. The authors have developed an inflatable, distributed capacitance, passively decoupled surface coil which is collapsed for insertion and reinflated for imaging. Images of the prostate are dramatically improved due to proximity of the coil. Lesions in cadaver specimens were observed which were not seen with body coil imaging. Clinical trials are expected to begin in September

  16. Egypt satellite images for land surface characterization

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay

    images used for mapping the vegetation cover types and other land cover types in Egypt. The mapping ranges from 1 km resolution to 30 m resolution. The aim is to provide satellite image mapping with land surface characteristics relevant for roughness mapping.......Satellite images provide information on the land surface properties. From optical remote sensing images in the blue, green, red and near-infrared part of the electromagnetic spectrum it is possible to identify a large number of surface features. The report briefly describes different satellite...

  17. Multiple interpretations of a pair of images of a surface

    Science.gov (United States)

    Longuet-Higgins, H. C.

    1988-07-01

    It is known that, if two optical images of a visually textured surface, projected from finitely separated viewpoints, allow more than one three-dimensional interpretation, then the surface must be part of a quadric passing through the two viewpoints. It is here shown that this quadric is either a plane or a ruled surface of a type first considered by Maybank (1985) in a study of ambiguous optic flow fields. In the latter case, three is the maximum number of distinct interpretations that the two images can sustain.

  18. Wireless Multiplexed Surface Acoustic Wave Sensors Project

    Science.gov (United States)

    Youngquist, Robert C.

    2014-01-01

    Wireless Surface Acoustic Wave (SAW) Sensor is a new technology for obtaining multiple, real-time measurements under extreme environmental conditions. This project plans to develop a wireless multiplexed sensor system that uses SAW sensors, with no batteries or semiconductors, that are passive and rugged, can operate down to cryogenic temperatures and up to hundreds of degrees C, and can be used to sense a wide variety of parameters over reasonable distances (meters).

  19. 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...

  20. Projection x-space magnetic particle imaging.

    Science.gov (United States)

    Goodwill, Patrick W; Konkle, Justin J; Zheng, Bo; Saritas, Emine U; Conolly, Steven M

    2012-05-01

    Projection magnetic particle imaging (MPI) can improve imaging speed by over 100-fold over traditional 3-D MPI. In this work, we derive the 2-D x-space signal equation, 2-D image equation, and introduce the concept of signal fading and resolution loss for a projection MPI imager. We then describe the design and construction of an x-space projection MPI scanner with a field gradient of 2.35 T/m across a 10 cm magnet free bore. The system has an expected resolution of 3.5 × 8.0 mm using Resovist tracer, and an experimental resolution of 3.8 × 8.4 mm resolution. The system images 2.5 cm × 5.0 cm partial field-of views (FOVs) at 10 frames/s, and acquires a full field-of-view of 10 cm × 5.0 cm in 4 s. We conclude by imaging a resolution phantom, a complex "Cal" phantom, mice injected with Resovist tracer, and experimentally confirm the theoretically predicted x-space spatial resolution.

  1. Projective and superconformal structures on surfaces

    International Nuclear Information System (INIS)

    Harvey, W.J.

    1990-01-01

    Much attention has recently been given to the study of super Riemann surfaces. Detailed accounts of these objects and their infinitesimal deformation theory are referenced where they are fitted into the framework of complex supermanifolds, superconformal structures and graded sheaves. One difficulty, which seems even more of a barrier than in the case of classical deformations of Riemann surface structure, is the lack of a good global description of super-moduli spaces. In this note, we outline an approach which places the theory in the classical setting of projective structures on variable Riemann surfaces. We explain how to construct a distribution (family of vector subspaces) inside the holomorphic cotangent space to the moduli space M g of Riemann surfaces with genus g and furnished with a level-4 homology structure, such that the corresponding rank-(2g-2) complex vector bundle models the soul deformations of a family of super-Riemann surfaces. The keystone in this construction is the existence of holomorphic sections for the space of non-singular odd theta characteristics on C g the universal curve over M g . (author)

  2. Imaging near-surface heterogeneities by natural migration of backscattered surface waves

    KAUST Repository

    AlTheyab, Abdullah

    2016-02-01

    We present a migration method that does not require a velocity model to migrate backscattered surface waves to their projected locations on the surface. This migration method, denoted as natural migration, uses recorded Green\\'s functions along the surface instead of simulated Green\\'s functions. The key assumptions are that the scattering bodies are within the depth interrogated by the surface waves, and the Green\\'s functions are recorded with dense receiver sampling along the free surface. This natural migration takes into account all orders of multiples, mode conversions and non-linear effects of surface waves in the data. The natural imaging formulae are derived for both active source and ambient-noise data, and computer simulations show that natural migration can effectively image near-surface heterogeneities with typical ambient-noise sources and geophone distributions.

  3. Information and image integration: project spectrum

    Science.gov (United States)

    Blaine, G. James; Jost, R. Gilbert; Martin, Lori; Weiss, David A.; Lehmann, Ron; Fritz, Kevin

    1998-07-01

    The BJC Health System (BJC) and the Washington University School of Medicine (WUSM) formed a technology alliance with industry collaborators to develop and implement an integrated, advanced clinical information system. The industry collaborators include IBM, Kodak, SBC and Motorola. The activity, called Project Spectrum, provides an integrated clinical repository for the multiple hospital facilities of the BJC. The BJC System consists of 12 acute care hospitals serving over one million patients in Missouri and Illinois. An interface engine manages transactions from each of the hospital information systems, lab systems and radiology information systems. Data is normalized to provide a consistent view for the primary care physician. Access to the clinical repository is supported by web-based server/browser technology which delivers patient data to the physician's desktop. An HL7 based messaging system coordinates the acquisition and management of radiological image data and sends image keys to the clinical data repository. Access to the clinical chart browser currently provides radiology reports, laboratory data, vital signs and transcribed medical reports. A chart metaphor provides tabs for the selection of the clinical record for review. Activation of the radiology tab facilitates a standardized view of radiology reports and provides an icon used to initiate retrieval of available radiology images. The selection of the image icon spawns an image browser plug-in and utilizes the image key from the clinical repository to access the image server for the requested image data. The Spectrum system is collecting clinical data from five hospital systems and imaging data from two hospitals. Domain specific radiology imaging systems support the acquisition and primary interpretation of radiology exams. The spectrum clinical workstations are deployed to over 200 sites utilizing local area networks and ISDN connectivity.

  4. Atomic profile imaging of ceramic oxide surfaces

    International Nuclear Information System (INIS)

    Bursill, L.A.; Peng JuLin; Sellar, J.R.

    1989-01-01

    Atomic surface profile imaging is an electron optical technique capable of revealing directly the surface crystallography of ceramic oxides. Use of an image-intensifier with a TV camera allows fluctuations in surface morphology and surface reactivity to be recorded and analyzed using digitized image data. This paper reviews aspects of the electron optical techniques, including interpretations based upon computer-simulation image-matching techniques. An extensive range of applications is then presented for ceramic oxides of commercial interest for advanced materials applications: including uranium oxide (UO 2 ); magnesium and nickel oxide (MgO,NiO); ceramic superconductor YBa 2 Cu 3 O 6.7 ); barium titanate (BaTiO 3 ); sapphire (α-A1 2 O 3 ); haematite (α-Fe-2O 3 ); monoclinic, tetragonal and cubic monocrystalline forms of zirconia (ZrO 2 ), lead zirconium titanate (PZT + 6 mol.% NiNbO 3 ) and ZBLAN fluoride glass. Atomic scale detail has been obtained of local structures such as steps associated with vicinal surfaces, facetting parallel to stable low energy crystallographic planes, monolayer formation on certain facets, relaxation and reconstructions, oriented overgrowth of lower oxides, chemical decomposition of complex oxides into component oxides, as well as amorphous coatings. This remarkable variety of observed surface stabilization mechanisms is discussed in terms of novel double-layer electrostatic depolarization mechanisms, as well as classical concepts of the physics and chemistry of surfaces (ionization and affinity energies and work function). 46 refs., 16 figs

  5. 3D surface reconstruction using optical flow for medical imaging

    International Nuclear Information System (INIS)

    Weng, Nan; Yang, Yee-Hong; Pierson, R.

    1996-01-01

    The recovery of a 3D model from a sequence of 2D images is very useful in medical image analysis. Image sequences obtained from the relative motion between the object and the camera or the scanner contain more 3D information than a single image. Methods to visualize the computed tomograms can be divided into two approaches: the surface rendering approach and the volume rendering approach. A new surface rendering method using optical flow is proposed. Optical flow is the apparent motion in the image plane produced by the projection of the real 3D motion onto 2D image. In this paper, the object remains stationary while the scanner undergoes translational motion. The 3D motion of an object can be recovered from the optical flow field using additional constraints. By extracting the surface information from 3D motion, it is possible to get an accurate 3D model of the object. Both synthetic and real image sequences have been used to illustrate the feasibility of the proposed method. The experimental results suggest that the proposed method is suitable for the reconstruction of 3D models from ultrasound medical images as well as other computed tomograms

  6. Invisibility cloak with image projection capability.

    Science.gov (United States)

    Banerjee, Debasish; Ji, Chengang; Iizuka, Hideo

    2016-12-13

    Investigations of invisibility cloaks have been led by rigorous theories and such cloak structures, in general, require extreme material parameters. Consequently, it is challenging to realize them, particularly in the full visible region. Due to the insensitivity of human eyes to the polarization and phase of light, cloaking a large object in the full visible region has been recently realized by a simplified theory. Here, we experimentally demonstrate a device concept where a large object can be concealed in a cloak structure and at the same time any images can be projected through it by utilizing a distinctively different approach; the cloaking via one polarization and the image projection via the other orthogonal polarization. Our device structure consists of commercially available optical components such as polarizers and mirrors, and therefore, provides a significant further step towards practical application scenarios such as transparent devices and see-through displays.

  7. MR imaging of brain surface structures

    International Nuclear Information System (INIS)

    Katada, Kazuhiro; Anno, Hirofumi; Takesita, Gen; Koga, Sukehiko; Kanno, Tetuo; Sakakibara, Tatuo; Yamada, Kazuhiro; Suzuki, Hirokazu; Saito, Sigeki.

    1989-01-01

    An imaging technique that permits direct and non-invasive visualization of brain surface structures was proposed. This technique (Surface anatomy scanning, SAS) consists of long TE-long TR spin echo sequence, thick slice and surface coil. Initial clinical trials in 31 patients with various cerebral pathology showed excellent visualization of sulci, gyri and major cortical veins on the lateral surface of the brain together with cortical and subcortical lesions. Our preliminary results indicate that the SAS is an effective method for the diagnosis and localization of cortical and subcortical pathology, and the possible application of SAS to the surgical and the radiation therapy planning is sugessted. (author)

  8. [Surface coils for magnetic-resonance images].

    Science.gov (United States)

    Rodríguez-González, Alfredo Odón; Amador-Baheza, Ricardo; Rojas-Jasso, Rafael; Barrios-Alvarez, Fernando Alejandro

    2005-01-01

    Since the introduction of magnetic resonance imaging in Mexico, the development of this important medical imaging technology has been almost non-existing in our country. The very first surface coil prototypes for clinical applications in magnetic resonance imaging has been developed at the Center of Research in Medical Imaging and Instrumentation of the Universidad Autónoma Metropolitana Iztapalapa (Metropolitan Autonomous University, Campus Iztapalapa). Two surface coil prototypes were built: a) a circular-shaped coil and b) a square-shaped coil for multiple regions of the body, such as heart, brain, knee, hands, and ankles. These coils were tested on the 1.5T imager of the ABC Hospital-Tacubaya, located in Mexico City. Brain images of healthy volunteers were obtained in different orientations: sagittal, coronal, and axial. Since images showed a good-enough clinical quality for diagnosis, it is fair to say that these coil prototypes can be used in the clinical environment, and with small modifications, they can be made compatible with almost any commercial scanner. This type of development can offer new alternatives for further collaboration between the research centers and the radiology community, in the search of new applications and developments of this imaging technique.

  9. Tablet surface characterisation by various imaging techniques

    DEFF Research Database (Denmark)

    Seitavuopio, Paulus; Rantanen, Jukka; Yliruusi, Jouko

    2003-01-01

    The aim of this study was to characterise tablet surfaces using different imaging and roughness analytical techniques including optical microscopy, scanning electron microscopy (SEM), laser profilometry and atomic force microscopy (AFM). The test materials compressed were potassium chloride (KCl......) and sodium chloride (NaCl). It was found that all methods used suggested that the KCl tablets were smoother than the NaCl tablets and higher compression pressure made the tablets smoother. Imaging methods like optical microscopy and SEM can give useful information about the roughness of the sample surface...

  10. A Toolbox for Imaging Stellar Surfaces

    Science.gov (United States)

    Young, John

    2018-04-01

    In this talk I will review the available algorithms for synthesis imaging at visible and infrared wavelengths, including both gray and polychromatic methods. I will explain state-of-the-art approaches to constraining the ill-posed image reconstruction problem, and selecting an appropriate regularisation function and strength of regularisation. The reconstruction biases that can follow from non-optimal choices will be discussed, including their potential impact on the physical interpretation of the results. This discussion will be illustrated with example stellar surface imaging results from real VLTI and COAST datasets.

  11. Divergent surface and total soil moisture projections under global warming

    Science.gov (United States)

    Berg, Alexis; Sheffield, Justin; Milly, Paul C.D.

    2017-01-01

    Land aridity has been projected to increase with global warming. Such projections are mostly based on off-line aridity and drought metrics applied to climate model outputs but also are supported by climate-model projections of decreased surface soil moisture. Here we comprehensively analyze soil moisture projections from the Coupled Model Intercomparison Project phase 5, including surface, total, and layer-by-layer soil moisture. We identify a robust vertical gradient of projected mean soil moisture changes, with more negative changes near the surface. Some regions of the northern middle to high latitudes exhibit negative annual surface changes but positive total changes. We interpret this behavior in the context of seasonal changes in the surface water budget. This vertical pattern implies that the extensive drying predicted by off-line drought metrics, while consistent with the projected decline in surface soil moisture, will tend to overestimate (negatively) changes in total soil water availability.

  12. 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

  13. Imaging the Surfaces of Stars from Space

    Science.gov (United States)

    Carpenter, Kenneth; Rau, Gioia

    2018-04-01

    Imaging of Stellar Surfacess has been dominated to-date by ground-based observations, but space-based facilities offer tremendous potential for extending the wavelength coverage and ultimately the resolution of such efforts. We review the imaging accomplished so far from space and then talk about exciting future prospects. The earliest attempts from space indirectly produced surface maps via the Doppler Imaging Technique, using UV spectra obtained with the International Ultraviolet Explorer (IUE). Later, the first direct UV images were obtained with the Hubble Space Telescope (HST), of Mira and Betelgeuse, using the Faint Object Camera (FOC). We will show this work and then investigate prospects for IR imaging with the James Webb Space Telescope (JWST). The real potential of space-based Imaging of Stellar Surfacess, however, lies in the future, when large-baseline Fizeau interferometers, such as the UV-optical Stellar Imager (SI) Vision Mission, with a 30-element array and 500m max baseline, are flown. We describe SI and its science goals, which include 0.1 milli-arcsec spectral Imaging of Stellar Surfacess and the probing of internal structure and flows via asteroseismology.

  14. 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.

  15. Ultrasonic imaging of projected components of PFBR

    Energy Technology Data Exchange (ETDEWEB)

    Sylvia, J.I., E-mail: sylvia@igcar.gov.in [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India); Jeyan, M.R.; Anbucheliyan, M.; Asokane, C.; Babu, V. Rajan; Babu, B.; Rajan, K.K.; Velusamy, K.; Jayakumar, T. [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India)

    2013-05-15

    Highlights: ► Under sodium ultrasonic scanner in PFBR is for detecting protruding objects. ► Feasibility study for detecting Absorber rods and its drive mechanisms. ► Developed in-house PC based ultrasonic imaging system. ► Different case studies were carried out on simulated ARDM's. ► Implemented the experimental results to PFBR application. -- Abstract: The 500 MWe, sodium cooled, Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam in India. Opacity of sodium restricts visual inspection of components immersed in sodium by optical means. Ultrasonic wave passes through sodium hence ultrasonic techniques using under sodium ultrasonic scanners are developed to obtain under sodium images. The main objective of such an Under Sodium Ultrasonic Scanner (USUSS) for Prototype Fast Breeder Reactor (PFBR) is to detect and ensure that no core Sub Assembly (SA) or Absorber Rod or its Drive Mechanism is protruded in the above core plenum before starting the fuel handling operation. Hence, it is necessary to detect and locate the object, if it is protruding the above core plenum. To study the feasibility of detecting the absorber rods and their drive mechanisms using direct ultrasonic imaging technique, experiments were carried out for different orientations and profiles of the projected components in a 5 m diameter water tank. The in-house developed PC based ultrasonic scanning system is used for acquisition and analysis of data. The pseudo three dimensional color images obtained are discussed and the results are applicable for PFBR. This paper gives the details of the features of the absorber rods and their drive mechanisms, their orientation in the reactor core, experimental setup, PC based ultrasonic scanning system, ultrasonic images and the discussion on the results.

  16. Distance of the image plane from metal surfaces

    International Nuclear Information System (INIS)

    Smith, N.V.; Chen, C.T.; Weinert, M.

    1989-01-01

    The data base of surface-state energies on the metals Cu, Ag, Au, Ni, Pd, and Pt is assembled and, with the aid of a simple model, is used to estimate the distance of the image plane and its trends from surface to surface and metal to metal. The model combines a nearly-free-electron representation of the crystal with a Jones-Jennings-Jepsen ansatz for the saturated image barrier. The projected bulk-band gaps are taken from published determinations. Constraints are placed on the surface barrier parameters by appeal to the results of self-consistent first-principles slab calculations. The general experimental trend observed is for the image-plane distance z 0 to decrease in the sequence (111) to (001) to (110), in the same sense but not as rapidly as z J , the distance of the effective jellium edge. This trend is rationalized using a simple model of the tail of the surface charge density. Typical values for z 0 -z J fall in the range -0.2 to +0.5 a.u., with the larger values occurring for the 3d metals Cu and Ni

  17. Tiny Devices Project Sharp, Colorful Images

    Science.gov (United States)

    2009-01-01

    Displaytech Inc., based in Longmont, Colorado and recently acquired by Micron Technology Inc. of Boise, Idaho, first received a Small Business Innovation Research contract in 1993 from Johnson Space Center to develop tiny, electronic, color displays, called microdisplays. Displaytech has since sold over 20 million microdisplays and was ranked one of the fastest growing technology companies by Deloitte and Touche in 2005. Customers currently incorporate the microdisplays in tiny pico-projectors, which weigh only a few ounces and attach to media players, cell phones, and other devices. The projectors can convert a digital image from the typical postage stamp size into a bright, clear, four-foot projection. The company believes sales of this type of pico-projector may exceed $1.1 billion within 5 years.

  18. Adaptive pixel-to-pixel projection intensity adjustment for measuring a shiny surface using orthogonal color fringe pattern projection

    Science.gov (United States)

    Chen, Chao; Gao, Nan; Wang, Xiangjun; Zhang, Zonghua

    2018-05-01

    Three-dimensional (3D) shape measurement based on fringe pattern projection techniques has been commonly used in various fields. One of the remaining challenges in fringe pattern projection is that camera sensor saturation may occur if there is a large range of reflectivity variation across the surface that causes measurement errors. To overcome this problem, a novel fringe pattern projection method is proposed to avoid image saturation and maintain high-intensity modulation for measuring shiny surfaces by adaptively adjusting the pixel-to-pixel projection intensity according to the surface reflectivity. First, three sets of orthogonal color fringe patterns and a sequence of uniform gray-level patterns with different gray levels are projected onto a measured surface by a projector. The patterns are deformed with respect to the object surface and captured by a camera from a different viewpoint. Subsequently, the optimal projection intensity at each pixel is determined by fusing different gray levels and transforming the camera pixel coordinate system into the projector pixel coordinate system. Finally, the adapted fringe patterns are created and used for 3D shape measurement. Experimental results on a flat checkerboard and shiny objects demonstrate that the proposed method can measure shiny surfaces with high accuracy.

  19. Surface Spectroscopy Center Of Excellence Project

    Science.gov (United States)

    Wooden, Diane

    2014-01-01

    We propose to develop a national center of excellence in Regolith Radiative Transfer (RRT), i.e., in modeling spectral reflectivity and emissivity of grainy or structured surfaces. The focus is the regime where the structural elements of grainy surfaces have grain sizes and separations of tens of microns, comparable to the wavelengths carrying diagnostic compositional information. This regime is of fundamental interest to remote sensing of planetary and terrestrial surfaces.

  20. Projections of Veronese surface and morphisms from projective ...

    Indian Academy of Sciences (India)

    In this article, we focus on the image of P2 in Gr(2, C4) associated to a globally gener- ated vector bundle Q with Chern class pair (c1(Q), c2(Q)) = (2, 2). More precisely, we have the following main theorem: Theorem 1.1. Let φ : P2 → Gr(2, C4) be a morphism. Assume that c1(Q) = 2 and c2(Q) = 2, where Q is the pull back by ...

  1. Method for Surface Scanning in Medical Imaging and Related Apparatus

    DEFF Research Database (Denmark)

    2015-01-01

    A method and apparatus for surface scanning in medical imaging is provided. The surface scanning apparatus comprises an image source, a first optical fiber bundle comprising first optical fibers having proximal ends and distal ends, and a first optical coupler for coupling an image from the image...

  2. Nuclear Fuel Assembly Assessment Project and Image Categorization

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey, C.S.; Lindblad, T.; Waldemark, K. [Royal Inst. of Tech., Stockholm (Sweden); Hildingsson, Lars [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    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

  3. Fast image matching algorithm based on projection characteristics

    Science.gov (United States)

    Zhou, Lijuan; Yue, Xiaobo; Zhou, Lijun

    2011-06-01

    Based on analyzing the traditional template matching algorithm, this paper identified the key factors restricting the speed of matching and put forward a brand new fast matching algorithm based on projection. Projecting the grayscale image, this algorithm converts the two-dimensional information of the image into one-dimensional one, and then matches and identifies through one-dimensional correlation, meanwhile, because of normalization has been done, when the image brightness or signal amplitude increasing in proportion, it could also perform correct matching. Experimental results show that the projection characteristics based image registration method proposed in this article could greatly improve the matching speed, which ensuring the matching accuracy as well.

  4. Low-cost rural surface alternatives : demonstration project.

    Science.gov (United States)

    2015-06-01

    The goals of this project were to implement several stabilization methods for preventing or mitigating freeze-thaw damage to : granular surfaced roads and identify the most effective and economical methods for the soil and climate conditions of Iowa....

  5. Biomechanical modeling constrained surface-based image registration for prostate MR guided TRUS biopsy

    NARCIS (Netherlands)

    Ven, W.J.M. van de; Hu, Y.; Barentsz, J.O.; Karssemeijer, N.; Barratt, D.; Huisman, H.J.

    2015-01-01

    Adding magnetic resonance (MR)-derived information to standard transrectal ultrasound (TRUS) images for guiding prostate biopsy is of substantial clinical interest. A tumor visible on MR images can be projected on ultrasound (US) by using MR-US registration. A common approach is to use surface-based

  6. Novel spirometry based on optical surface imaging

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guang, E-mail: lig2@mskcc.org; Huang, Hailiang; Li, Diana G.; Chen, Qing; Gaebler, Carl P.; Mechalakos, James [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Wei, Jie [Department of Computer Science, City College of New York, New York, New York 10031 (United States); Sullivan, James [Pulmonary Laboratories, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Zatcky, Joan; Rimner, Andreas [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States)

    2015-04-15

    Purpose: To evaluate the feasibility of using optical surface imaging (OSI) to measure the dynamic tidal volume (TV) of the human torso during free breathing. Methods: We performed experiments to measure volume or volume change in geometric and deformable phantoms as well as human subjects using OSI. To assess the accuracy of OSI in volume determination, we performed experiments using five geometric phantoms and two deformable body phantoms and compared the values with those derived from geometric calculations and computed tomography (CT) measurements, respectively. To apply this technique to human subjects, an institutional review board protocol was established and three healthy volunteers were studied. In the human experiment, a high-speed image capture mode of OSI was applied to acquire torso images at 4–5 frames per second, which was synchronized with conventional spirometric measurements at 5 Hz. An in-house MATLAB program was developed to interactively define the volume of interest (VOI), separate the thorax and abdomen, and automatically calculate the thoracic and abdominal volumes within the VOIs. The torso volume change (TV C = ΔV{sub torso} = ΔV{sub thorax} + ΔV{sub abdomen}) was automatically calculated using full-exhalation phase as the reference. The volumetric breathing pattern (BP{sub v} = ΔV{sub thorax}/ΔV{sub torso}) quantifying thoracic and abdominal volume variations was also calculated. Under quiet breathing, TVC should equal the tidal volume measured concurrently by a spirometer with a conversion factor (1.08) accounting for internal and external differences of temperature and moisture. Another MATLAB program was implemented to control the conventional spirometer that was used as the standard. Results: The volumes measured from the OSI imaging of geometric phantoms agreed with the calculated volumes with a discrepancy of 0.0% ± 1.6% (range −1.9% to 2.5%). In measurements from the deformable torso/thorax phantoms, the volume

  7. Novel spirometry based on optical surface imaging

    International Nuclear Information System (INIS)

    Li, Guang; Huang, Hailiang; Li, Diana G.; Chen, Qing; Gaebler, Carl P.; Mechalakos, James; Wei, Jie; Sullivan, James; Zatcky, Joan; Rimner, Andreas

    2015-01-01

    Purpose: To evaluate the feasibility of using optical surface imaging (OSI) to measure the dynamic tidal volume (TV) of the human torso during free breathing. Methods: We performed experiments to measure volume or volume change in geometric and deformable phantoms as well as human subjects using OSI. To assess the accuracy of OSI in volume determination, we performed experiments using five geometric phantoms and two deformable body phantoms and compared the values with those derived from geometric calculations and computed tomography (CT) measurements, respectively. To apply this technique to human subjects, an institutional review board protocol was established and three healthy volunteers were studied. In the human experiment, a high-speed image capture mode of OSI was applied to acquire torso images at 4–5 frames per second, which was synchronized with conventional spirometric measurements at 5 Hz. An in-house MATLAB program was developed to interactively define the volume of interest (VOI), separate the thorax and abdomen, and automatically calculate the thoracic and abdominal volumes within the VOIs. The torso volume change (TV C = ΔV torso = ΔV thorax + ΔV abdomen ) was automatically calculated using full-exhalation phase as the reference. The volumetric breathing pattern (BP v = ΔV thorax /ΔV torso ) quantifying thoracic and abdominal volume variations was also calculated. Under quiet breathing, TVC should equal the tidal volume measured concurrently by a spirometer with a conversion factor (1.08) accounting for internal and external differences of temperature and moisture. Another MATLAB program was implemented to control the conventional spirometer that was used as the standard. Results: The volumes measured from the OSI imaging of geometric phantoms agreed with the calculated volumes with a discrepancy of 0.0% ± 1.6% (range −1.9% to 2.5%). In measurements from the deformable torso/thorax phantoms, the volume differences measured using OSI

  8. 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)

  9. Atomic Resolution Imaging and Quantification of Chemical Functionality of Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, Udo D. [Yale Univ., New Haven, CT (United States). Dept. of Mechanical Engineering and Materials Science; Altman, Eric I. [Yale Univ., New Haven, CT (United States). Dept. of Chemical and Environmental Engineering

    2014-12-10

    The work carried out from 2006-2014 under DoE support was targeted at developing new approaches to the atomic-scale characterization of surfaces that include species-selective imaging and an ability to quantify chemical surface interactions with site-specific accuracy. The newly established methods were subsequently applied to gain insight into the local chemical interactions that govern the catalytic properties of model catalysts of interest to DoE. The foundation of our work was the development of three-dimensional atomic force microscopy (3DAFM), a new measurement mode that allows the mapping of the complete surface force and energy fields with picometer resolution in space (x, y, and z) and piconewton/millielectron volts in force/energy. From this experimental platform, we further expanded by adding the simultaneous recording of tunneling current (3D-AFM/STM) using chemically well-defined tips. Through comparison with simulations, we were able to achieve precise quantification and assignment of local chemical interactions to exact positions within the lattice. During the course of the project, the novel techniques were applied to surface-oxidized copper, titanium dioxide, and silicon oxide. On these materials, defect-induced changes to the chemical surface reactivity and electronic charge density were characterized with site-specific accuracy.

  10. [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.

  11. Hybrid surface platform for the simultaneous detection of proteins and DNA using a surface plasmon resonance (SPR) imaging sensor

    Czech Academy of Sciences Publication Activity Database

    Homola, Jiří; Piliarik, Marek; Ladd, J.; Taylor, A.; Shaoyi, J.

    2008-01-01

    Roč. 80, č. 11 (2008), s. 4231-4236 ISSN 0003-2700 R&D Projects: GA AV ČR KAN200670701 Institutional research plan: CEZ:AV0Z20670512 Keywords : Surface plasmon resonance imaging * DNA-directed immobilization * protein array Subject RIV: JB - Sensors, Measurment, Regulation Impact factor: 5.712, year: 2008

  12. Projections onto the Pareto surface in multicriteria radiation therapy optimization.

    Science.gov (United States)

    Bokrantz, Rasmus; Miettinen, Kaisa

    2015-10-01

    To eliminate or reduce the error to Pareto optimality that arises in Pareto surface navigation when the Pareto surface is approximated by a small number of plans. The authors propose to project the navigated plan onto the Pareto surface as a postprocessing step to the navigation. The projection attempts to find a Pareto optimal plan that is at least as good as or better than the initial navigated plan with respect to all objective functions. An augmented form of projection is also suggested where dose-volume histogram constraints are used to prevent that the projection causes a violation of some clinical goal. The projections were evaluated with respect to planning for intensity modulated radiation therapy delivered by step-and-shoot and sliding window and spot-scanned intensity modulated proton therapy. Retrospective plans were generated for a prostate and a head and neck case. The projections led to improved dose conformity and better sparing of organs at risk (OARs) for all three delivery techniques and both patient cases. The mean dose to OARs decreased by 3.1 Gy on average for the unconstrained form of the projection and by 2.0 Gy on average when dose-volume histogram constraints were used. No consistent improvements in target homogeneity were observed. There are situations when Pareto navigation leaves room for improvement in OAR sparing and dose conformity, for example, if the approximation of the Pareto surface is coarse or the problem formulation has too permissive constraints. A projection onto the Pareto surface can identify an inaccurate Pareto surface representation and, if necessary, improve the quality of the navigated plan.

  13. Projections onto the Pareto surface in multicriteria radiation therapy optimization

    International Nuclear Information System (INIS)

    Bokrantz, Rasmus; Miettinen, Kaisa

    2015-01-01

    Purpose: To eliminate or reduce the error to Pareto optimality that arises in Pareto surface navigation when the Pareto surface is approximated by a small number of plans. Methods: The authors propose to project the navigated plan onto the Pareto surface as a postprocessing step to the navigation. The projection attempts to find a Pareto optimal plan that is at least as good as or better than the initial navigated plan with respect to all objective functions. An augmented form of projection is also suggested where dose–volume histogram constraints are used to prevent that the projection causes a violation of some clinical goal. The projections were evaluated with respect to planning for intensity modulated radiation therapy delivered by step-and-shoot and sliding window and spot-scanned intensity modulated proton therapy. Retrospective plans were generated for a prostate and a head and neck case. Results: The projections led to improved dose conformity and better sparing of organs at risk (OARs) for all three delivery techniques and both patient cases. The mean dose to OARs decreased by 3.1 Gy on average for the unconstrained form of the projection and by 2.0 Gy on average when dose–volume histogram constraints were used. No consistent improvements in target homogeneity were observed. Conclusions: There are situations when Pareto navigation leaves room for improvement in OAR sparing and dose conformity, for example, if the approximation of the Pareto surface is coarse or the problem formulation has too permissive constraints. A projection onto the Pareto surface can identify an inaccurate Pareto surface representation and, if necessary, improve the quality of the navigated plan

  14. Imaging near-surface heterogeneities by natural migration of surface waves

    KAUST Repository

    Liu, Zhaolun; AlTheyab, Abdullah; Hanafy, Sherif M.; Schuster, Gerard T.

    2016-01-01

    We demonstrate that near-surface heterogeneities can be imaged by natural migration of backscattered surface waves in common shot gathers. No velocity model is required because the data are migrated onto surface points with the virtual Green

  15. Focused surface coil for MR imaging of the pituitary

    International Nuclear Information System (INIS)

    Harms, S.E.; Sherry, C.S.; Youshimura, L.; Lokken, R.; Hyde, J.S.

    1987-01-01

    A specially designed surface coil for pituitary MR imaging results in improved image quality over that achieved with conventional pituitary Mr imaging. The coil consists of connected planar pair coils with a variable intercoil distance to accommodate differences in head size. The sensitive field is focused deep to the surface between the two planar pairs. This arrangement optimizes the signal-to-noise ratio and allows better gradient magnification of the pituitary region. Fifteen subjects with a variety of pituitary disorders were imaged

  16. The developing human connectome project: A minimal processing pipeline for neonatal cortical surface reconstruction.

    Science.gov (United States)

    Makropoulos, Antonios; Robinson, Emma C; Schuh, Andreas; Wright, Robert; Fitzgibbon, Sean; Bozek, Jelena; Counsell, Serena J; Steinweg, Johannes; Vecchiato, Katy; Passerat-Palmbach, Jonathan; Lenz, Gregor; Mortari, Filippo; Tenev, Tencho; Duff, Eugene P; Bastiani, Matteo; Cordero-Grande, Lucilio; Hughes, Emer; Tusor, Nora; Tournier, Jacques-Donald; Hutter, Jana; Price, Anthony N; Teixeira, Rui Pedro A G; Murgasova, Maria; Victor, Suresh; Kelly, Christopher; Rutherford, Mary A; Smith, Stephen M; Edwards, A David; Hajnal, Joseph V; Jenkinson, Mark; Rueckert, Daniel

    2018-06-01

    The Developing Human Connectome Project (dHCP) seeks to create the first 4-dimensional connectome of early life. Understanding this connectome in detail may provide insights into normal as well as abnormal patterns of brain development. Following established best practices adopted by the WU-MINN Human Connectome Project (HCP), and pioneered by FreeSurfer, the project utilises cortical surface-based processing pipelines. In this paper, we propose a fully automated processing pipeline for the structural Magnetic Resonance Imaging (MRI) of the developing neonatal brain. This proposed pipeline consists of a refined framework for cortical and sub-cortical volume segmentation, cortical surface extraction, and cortical surface inflation, which has been specifically designed to address considerable differences between adult and neonatal brains, as imaged using MRI. Using the proposed pipeline our results demonstrate that images collected from 465 subjects ranging from 28 to 45 weeks post-menstrual age (PMA) can be processed fully automatically; generating cortical surface models that are topologically correct, and correspond well with manual evaluations of tissue boundaries in 85% of cases. Results improve on state-of-the-art neonatal tissue segmentation models and significant errors were found in only 2% of cases, where these corresponded to subjects with high motion. Downstream, these surfaces will enhance comparisons of functional and diffusion MRI datasets, supporting the modelling of emerging patterns of brain connectivity. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Descriptive and Computer Aided Drawing Perspective on an Unfolded Polyhedral Projection Surface

    Science.gov (United States)

    Dzwierzynska, Jolanta

    2017-10-01

    The aim of the herby study is to develop a method of direct and practical mapping of perspective on an unfolded prism polyhedral projection surface. The considered perspective representation is a rectilinear central projection onto a surface composed of several flat elements. In the paper two descriptive methods of drawing perspective are presented: direct and indirect. The graphical mapping of the effects of the representation is realized directly on the unfolded flat projection surface. That is due to the projective and graphical connection between points displayed on the polyhedral background and their counterparts received on the unfolded flat surface. For a significant improvement of the construction of line, analytical algorithms are formulated. They draw a perspective image of a segment of line passing through two different points determined by their coordinates in a spatial coordinate system of axis x, y, z. Compared to other perspective construction methods that use information about points, for computer vision and the computer aided design, our algorithms utilize data about lines, which are applied very often in architectural forms. Possibility of drawing lines in the considered perspective enables drawing an edge perspective image of an architectural object. The application of the changeable base elements of perspective as a horizon height and a station point location enable drawing perspective image from different viewing positions. The analytical algorithms for drawing perspective images are formulated in Mathcad software, however, they can be implemented in the majority of computer graphical packages, which can make drawing perspective more efficient and easier. The representation presented in the paper and the way of its direct mapping on the flat unfolded projection surface can find application in presentation of architectural space in advertisement and art.

  18. Superresolution Near-field Imaging with Surface Waves

    KAUST Repository

    Fu, Lei; Liu, Zhaolun; Schuster, Gerard T.

    2017-01-01

    We present the theory for near-field superresolution imaging with surface waves and time reverse mirrors (TRMs). Theoretical formulas and numerical results show that applying the TRM operation to surface waves in an elastic half-space can achieve

  19. Scanned Image Projection System Employing Intermediate Image Plane

    Science.gov (United States)

    DeJong, Christian Dean (Inventor); Hudman, Joshua M. (Inventor)

    2014-01-01

    In imaging system, a spatial light modulator is configured to produce images by scanning a plurality light beams. A first optical element is configured to cause the plurality of light beams to converge along an optical path defined between the first optical element and the spatial light modulator. A second optical element is disposed between the spatial light modulator and a waveguide. The first optical element and the spatial light modulator are arranged such that an image plane is created between the spatial light modulator and the second optical element. The second optical element is configured to collect the diverging light from the image plane and collimate it. The second optical element then delivers the collimated light to a pupil at an input of the waveguide.

  20. 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.

  1. Imaging method of brain surface anatomy structures using conventional T2-weighted MR images

    International Nuclear Information System (INIS)

    Hatanaka, Masahiko; Machida, Yoshio; Yoshida, Tadatoki; Katada, Kazuhiro.

    1992-01-01

    As a non-invasive technique for visualizing the brain surface structure by MRI, surface anatomy scanning (SAS) and the multislice SAS methods have been developed. Both techniques require additional MRI scanning to obtain images for the brain surface. In this paper, we report an alternative method to obtain the brain surface image using conventional T2-weighted multislice images without any additional scanning. The power calculation of the image pixel values, which is incorporated in the routine processing, has been applied in order to enhance the cerebrospinal fluid (CSF) contrast. We think that this method is one of practical approaches for imaging the surface anatomy of the brain. (author)

  2. The caBIG annotation and image Markup project.

    Science.gov (United States)

    Channin, David S; Mongkolwat, Pattanasak; Kleper, Vladimir; Sepukar, Kastubh; Rubin, Daniel L

    2010-04-01

    Image annotation and markup are at the core of medical interpretation in both the clinical and the research setting. Digital medical images are managed with the DICOM standard format. While DICOM contains a large amount of meta-data about whom, where, and how the image was acquired, DICOM says little about the content or meaning of the pixel data. An image annotation is the explanatory or descriptive information about the pixel data of an image that is generated by a human or machine observer. An image markup is the graphical symbols placed over the image to depict an annotation. While DICOM is the standard for medical image acquisition, manipulation, transmission, storage, and display, there are no standards for image annotation and markup. Many systems expect annotation to be reported verbally, while markups are stored in graphical overlays or proprietary formats. This makes it difficult to extract and compute with both of them. The goal of the Annotation and Image Markup (AIM) project is to develop a mechanism, for modeling, capturing, and serializing image annotation and markup data that can be adopted as a standard by the medical imaging community. The AIM project produces both human- and machine-readable artifacts. This paper describes the AIM information model, schemas, software libraries, and tools so as to prepare researchers and developers for their use of AIM.

  3. 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...

  4. Cross Cultural Images: The ETSU/NAU Special Photography Project.

    Science.gov (United States)

    Montgomery, Donna; Sluss, Dorothy; Lewis, Jamie; Vervelde, Peggy; Prater, Greg; Minner, Sam

    Recreation is a significant part of a full and rich life but is frequently overlooked in relation to handicapped children. A project called Cross-Cultural Images aimed to improve the quality of life for handicapped children by teaching them avocational photography skills. The project involved mildly handicapped children aged 7-11 in Appalachia, on…

  5. Dual scan CT image recovery from truncated projections

    Science.gov (United States)

    Sarkar, Shubhabrata; Wahi, Pankaj; Munshi, Prabhat

    2017-12-01

    There are computerized tomography (CT) scanners available commercially for imaging small objects and they are often categorized as mini-CT X-ray machines. One major limitation of these machines is their inability to scan large objects with good image quality because of the truncation of projection data. An algorithm is proposed in this work which enables such machines to scan large objects while maintaining the quality of the recovered image.

  6. 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)

  7. 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.

  8. Project of the Year Submittal SY-101 Surface Level Rise Remediation Project

    International Nuclear Information System (INIS)

    BAUER, R.E.

    2001-01-01

    CH2M HILL Hanford Group is pleased to nominate the SY-101 Surface Level Rise Remediation Project (SLRRP) for the Project Management Institute's consideration as International Project of the Year for 2001. We selected this project as being our best recent example of effective project management, having achieved and exceeded our client's expectations in resolving urgent safety issues related to the storage of high level nuclear waste. In reflection, we consider the SY-101 SLRRP to be a prime example of safe and effective project delivery. The pages that follow present the tools and techniques employed to manage this complex and technically challenging project. Our objective in submitting this nomination is twofold--to share the lessons we have learned with other organizations, and to honor the men and women who contributed to this endeavor. It was by their diligent effort that the successes we relate here were accomplished 10 months ahead of schedule and one million dollars below the authorized budget

  9. Reconstruction of CT images by the Bayes- back projection method

    CERN Document Server

    Haruyama, M; Takase, M; Tobita, H

    2002-01-01

    In the course of research on quantitative assay of non-destructive measurement of radioactive waste, the have developed a unique program based on the Bayesian theory for reconstruction of transmission computed tomography (TCT) image. The reconstruction of cross-section images in the CT technology usually employs the Filtered Back Projection method. The new imaging reconstruction program reported here is based on the Bayesian Back Projection method, and it has a function of iterative improvement images by every step of measurement. Namely, this method has the capability of prompt display of a cross-section image corresponding to each angled projection data from every measurement. Hence, it is possible to observe an improved cross-section view by reflecting each projection data in almost real time. From the basic theory of Baysian Back Projection method, it can be not only applied to CT types of 1st, 2nd, and 3rd generation. This reported deals with a reconstruction program of cross-section images in the CT of ...

  10. Quantitative roughness characterization and 3D reconstruction of electrode surface using cyclic voltammetry and SEM image

    Energy Technology Data Exchange (ETDEWEB)

    Dhillon, Shweta; Kant, Rama, E-mail: rkant@chemistry.du.ac.in

    2013-10-01

    Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.

  11. Quantitative roughness characterization and 3D reconstruction of electrode surface using cyclic voltammetry and SEM image

    International Nuclear Information System (INIS)

    Dhillon, Shweta; Kant, Rama

    2013-01-01

    Area measurements from cyclic voltammetry (CV) and image from scanning electron microscopy (SEM) are used to characterize electrode statistical morphology, 3D surface reconstruction and its electroactivity. SEM images of single phased materials correspond to two-dimensional (2D) projections of 3D structures, leading to an incomplete characterization. Lack of third dimension information in SEM image is circumvented using equivalence between denoised SEM image and CV area measurements. This CV-SEM method can be used to estimate power spectral density (PSD), width, gradient, finite fractal nature of roughness and local morphology of the electrode. We show that the surface morphological statistical property like distribution function of gradient can be related to local electro-activity. Electrode surface gradient micrographs generated here can provide map of electro-activity sites. Finally, the densely and uniformly packed small gradient over the Pt-surface is the determining criterion for high intrinsic electrode activity.

  12. High resolution imaging of surface patterns of single bacterial cells

    International Nuclear Information System (INIS)

    Greif, Dominik; Wesner, Daniel; Regtmeier, Jan; Anselmetti, Dario

    2010-01-01

    We systematically studied the origin of surface patterns observed on single Sinorhizobium meliloti bacterial cells by comparing the complementary techniques atomic force microscopy (AFM) and scanning electron microscopy (SEM). Conditions ranged from living bacteria in liquid to fixed bacteria in high vacuum. Stepwise, we applied different sample modifications (fixation, drying, metal coating, etc.) and characterized the observed surface patterns. A detailed analysis revealed that the surface structure with wrinkled protrusions in SEM images were not generated de novo but most likely evolved from similar and naturally present structures on the surface of living bacteria. The influence of osmotic stress to the surface structure of living cells was evaluated and also the contribution of exopolysaccharide and lipopolysaccharide (LPS) by imaging two mutant strains of the bacterium under native conditions. AFM images of living bacteria in culture medium exhibited surface structures of the size of single proteins emphasizing the usefulness of AFM for high resolution cell imaging.

  13. Imaging near-surface heterogeneities by natural migration of backscattered surface waves

    KAUST Repository

    AlTheyab, Abdullah; Lin, Fan-Chi; Schuster, Gerard T.

    2016-01-01

    We present a migration method that does not require a velocity model to migrate backscattered surface waves to their projected locations on the surface. This migration method, denoted as natural migration, uses recorded Green's functions along

  14. Fermi surface contours obtained from scanning tunneling microscope images around surface point defects

    International Nuclear Information System (INIS)

    Khotkevych-Sanina, N V; Kolesnichenko, Yu A; Van Ruitenbeek, J M

    2013-01-01

    We present a theoretical analysis of the standing wave patterns in scanning tunneling microscope (STM) images, which occur around surface point defects. We consider arbitrary dispersion relations for the surface states and calculate the conductance for a system containing a small-size tunnel contact and a surface impurity. We find rigorous theoretical relations between the interference patterns in the real-space STM images, their Fourier transforms and the Fermi contours of two-dimensional electrons. We propose a new method for reconstructing Fermi contours of surface electron states, directly from the real-space STM images around isolated surface defects. (paper)

  15. Quantitative estimation of brain atrophy and function with PET and MRI two-dimensional projection images

    International Nuclear Information System (INIS)

    Saito, Reiko; Uemura, Koji; Uchiyama, Akihiko; Toyama, Hinako; Ishii, Kenji; Senda, Michio

    2001-01-01

    The purpose of this paper is to estimate the extent of atrophy and the decline in brain function objectively and quantitatively. Two-dimensional (2D) projection images of three-dimensional (3D) transaxial images of positron emission tomography (PET) and magnetic resonance imaging (MRI) were made by means of the Mollweide method which keeps the area of the brain surface. A correlation image was generated between 2D projection images of MRI and cerebral blood flow (CBF) or 18 F-fluorodeoxyglucose (FDG) PET images and the sulcus was extracted from the correlation image clustered by K-means method. Furthermore, the extent of atrophy was evaluated from the extracted sulcus on 2D-projection MRI and the cerebral cortical function such as blood flow or glucose metabolic rate was assessed in the cortex excluding sulcus on 2D-projection PET image, and then the relationship between the cerebral atrophy and function was evaluated. This method was applied to the two groups, the young and the aged normal subjects, and the relationship between the age and the rate of atrophy or the cerebral blood flow was investigated. This method was also applied to FDG-PET and MRI studies in the normal controls and in patients with corticobasal degeneration. The mean rate of atrophy in the aged group was found to be higher than that in the young. The mean value and the variance of the cerebral blood flow for the young are greater than those of the aged. The sulci were similarly extracted using either CBF or FDG PET images. The purposed method using 2-D projection images of MRI and PET is clinically useful for quantitative assessment of atrophic change and functional disorder of cerebral cortex. (author)

  16. Nonabelian Jacobian of projective surfaces geometry and representation theory

    CERN Document Server

    Reider, Igor

    2013-01-01

    The Jacobian of a smooth projective curve is undoubtedly one of the most remarkable and beautiful objects in algebraic geometry. This work is an attempt to develop an analogous theory for smooth projective surfaces - a theory of the nonabelian Jacobian of smooth projective surfaces. Just like its classical counterpart, our nonabelian Jacobian relates to vector bundles (of rank 2) on a surface as well as its Hilbert scheme of points. But it also comes equipped with the variation of Hodge-like structures, which produces a sheaf of reductive Lie algebras naturally attached to our Jacobian. This constitutes a nonabelian analogue of the (abelian) Lie algebra structure of the classical Jacobian. This feature naturally relates geometry of surfaces with the representation theory of reductive Lie algebras/groups. This work’s main focus is on providing an in-depth study of various aspects of this relation. It presents a substantial body of evidence that the sheaf of Lie algebras on the nonabelian Jacobian is an effic...

  17. 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

  18. UMTRA Surface Project management action process document: Final. Revision 2

    International Nuclear Information System (INIS)

    1996-06-01

    Title 1 of the UMTRCA authorized the DOE to undertake remedial actions at these designed sites and associated vicinity properties (VP), which contain uranium mill tailings and other residual radioactive materials (RRM) derived from the processing sites. Title 2 of the UMTRCA addresses uranium mill sites that were licensed at the time the UMTRCA was enacted. Cleanup of these Title 2 sites is the responsibility of the licensees. The cleanup of the Title 1 sites has been split into two separate projects: the Surface Project, which deals with the mill buildings, tailings, and contaminated soils at the sites and VPs; and the Ground Water Project, which is limited to the contaminated ground water at the sites. This management action process (MAP) document discusses the Uranium Mill Tailings Remedial Action (UMTRA) Surface Project. Since its inception through March 1996, the Surface Project (hereinafter called the Project) has cleaned up 16 of the 24 designated processing sites and approximately 5,000 VPs, reducing the risk to human health and the environment posed by the uranium mill tailings. Two of the 24 sites, Belfield and Bowman, North Dakota, will not be remediated at the request of the state, reducing the total number of sites to 22. By the start of FY1998, the remaining 6 processing sites and associated VPs will be cleaned up. The remedial action activities to be funded in FY1998 by the FY1998 budget request are remediation of the remaining Grand Junction, Colorado, VPs; closure of the Cheney disposal cell in Grand Junction, Colorado; and preparation of the completion reports for 4 completed sites

  19. UMTRA Surface Project management action process document: Final. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    Title 1 of the UMTRCA authorized the DOE to undertake remedial actions at these designed sites and associated vicinity properties (VP), which contain uranium mill tailings and other residual radioactive materials (RRM) derived from the processing sites. Title 2 of the UMTRCA addresses uranium mill sites that were licensed at the time the UMTRCA was enacted. Cleanup of these Title 2 sites is the responsibility of the licensees. The cleanup of the Title 1 sites has been split into two separate projects: the Surface Project, which deals with the mill buildings, tailings, and contaminated soils at the sites and VPs; and the Ground Water Project, which is limited to the contaminated ground water at the sites. This management action process (MAP) document discusses the Uranium Mill Tailings Remedial Action (UMTRA) Surface Project. Since its inception through March 1996, the Surface Project (hereinafter called the Project) has cleaned up 16 of the 24 designated processing sites and approximately 5,000 VPs, reducing the risk to human health and the environment posed by the uranium mill tailings. Two of the 24 sites, Belfield and Bowman, North Dakota, will not be remediated at the request of the state, reducing the total number of sites to 22. By the start of FY1998, the remaining 6 processing sites and associated VPs will be cleaned up. The remedial action activities to be funded in FY1998 by the FY1998 budget request are remediation of the remaining Grand Junction, Colorado, VPs; closure of the Cheney disposal cell in Grand Junction, Colorado; and preparation of the completion reports for 4 completed sites.

  20. Energy utilization in surface mining project : with case study illustration

    International Nuclear Information System (INIS)

    Sinha, D.K.; De, Amitosh

    1992-01-01

    The importance of reducing energy consumption per tonne of output in the mining projects needs an innovative approach and style to change the behaviour and postures of the technical characteristics. The need for suitable energy policy can not be overlooked with the addition of new large size surface mining projects having a lot of technological development. But the immediate prescription to the problem is to pinpoint specific high energy consuming areas prefixed by thorough diagnosis and followed by deep scientific thought into it. To that extent this paper makes a primary attempt to characterise the various problems. (author). 7 tabs

  1. The Van Sant AVHRR image projected onto a rhombicosidodecahedron

    Science.gov (United States)

    Baron, Michael; Morain, Stan

    1996-03-01

    IDEATION, a design and development corporation, Santa Fe, New Mexico, has modeled Tom Van Sant's ``The Earth From Space'' image to a rhombicosidodecahedron. ``The Earth from Space'' image, produced by the Geosphere® Project in Santa Monica, California, was developed from hundreds of AVHRR pictures and published as a Mercator projection. IDEATION, utilizing a digitized Robinson Projection, fitted the image to foldable, paper components which, when interconnected by means of a unique tabular system, results in a rhombicosidodecahedron representation of the Earth exposing 30 square, 20 triangular, and 12 pentagonal faces. Because the resulting model is not spherical, the borders of the represented features were rectified to match the intersecting planes of the model's faces. The resulting product will be licensed and commercially produced for use by elementary and secondary students. Market research indicates the model will be used in both the demonstration of geometric principles and the teaching of fundamental spatial relations of the Earth's lands and oceans.

  2. 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

  3. Free Surface Downgoing VSP Multiple Imaging

    Science.gov (United States)

    Maula, Fahdi; Dac, Nguyen

    2018-03-01

    The common usage of a vertical seismic profile is to capture the reflection wavefield (upgoing wavefield) so that it can be used for further well tie or other interpretations. Borehole Seismic (VSP) receivers capture the reflection from below the well trajectory, traditionally no seismic image information above trajectory. The non-traditional way of processing the VSP multiple can be used to expand the imaging above the well trajectory. This paper presents the case study of using VSP downgoing multiples for further non-traditional imaging applications. In general, VSP processing, upgoing and downgoing arrivals are separated during processing. The up-going wavefield is used for subsurface illumination, whereas the downgoing wavefield and multiples are normally excluded from the processing. In a situation where the downgoing wavefield passes the reflectors several times (multiple), the downgoing wavefield carries reflection information. Its benefit is that it can be used for seismic tie up to seabed, and possibility for shallow hazards identifications. One of the concepts of downgoing imaging is widely known as mirror-imaging technique. This paper presents a case study from deep water offshore Vietnam. The case study is presented to demonstrate the robustness of the technique, and the limitations encountered during its processing.

  4. Moduli spaces of convex projective structures on surfaces

    DEFF Research Database (Denmark)

    Fock, V. V.; Goncharov, A. B.

    2007-01-01

    We introduce explicit parametrisations of the moduli space of convex projective structures on surfaces, and show that the latter moduli space is identified with the higher Teichmüller space for defined in [V.V. Fock, A.B. Goncharov, Moduli spaces of local systems and higher Teichmüller theory, math.......AG/0311149]. We investigate the cluster structure of this moduli space, and define its quantum version....

  5. Smooth embeddings with Stein surface images

    OpenAIRE

    Gompf, Robert E.

    2011-01-01

    A simple characterization is given of open subsets of a complex surface that smoothly perturb to Stein open subsets. As applications, complex 2-space C^2 contains domains of holomorphy (Stein open subsets) that are exotic R^4's, and others homotopy equivalent to the 2-sphere but cut out by smooth, compact 3-manifolds. Pseudoconvex embeddings of Brieskorn spheres and other 3-manifolds into complex surfaces are constructed, as are pseudoconcave holomorphic fillings (with disagreeing contact and...

  6. Anisotropic conductivity imaging with MREIT using equipotential projection algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Degirmenci, Evren [Department of Electrical and Electronics Engineering, Mersin University, Mersin (Turkey); Eyueboglu, B Murat [Department of Electrical and Electronics Engineering, Middle East Technical University, 06531, Ankara (Turkey)

    2007-12-21

    Magnetic resonance electrical impedance tomography (MREIT) combines magnetic flux or current density measurements obtained by magnetic resonance imaging (MRI) and surface potential measurements to reconstruct images of true conductivity with high spatial resolution. Most of the biological tissues have anisotropic conductivity; therefore, anisotropy should be taken into account in conductivity image reconstruction. Almost all of the MREIT reconstruction algorithms proposed to date assume isotropic conductivity distribution. In this study, a novel MREIT image reconstruction algorithm is proposed to image anisotropic conductivity. Relative anisotropic conductivity values are reconstructed iteratively, using only current density measurements without any potential measurement. In order to obtain true conductivity values, only either one potential or conductivity measurement is sufficient to determine a scaling factor. The proposed technique is evaluated on simulated data for isotropic and anisotropic conductivity distributions, with and without measurement noise. Simulation results show that the images of both anisotropic and isotropic conductivity distributions can be reconstructed successfully.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. Surface displacement imaging by interferometry with a light emitting diode

    International Nuclear Information System (INIS)

    Dilhaire, Stefan; Grauby, Stephane; Jorez, Sebastien; Lopez, Luis David Patino; Rampnoux, Jean-Michel; Claeys, Wilfrid

    2002-01-01

    We present an imaging technique to measure static surface displacements of electronic components. A device is supplied by a transient current that creates a variation of temperature, thus a surface displacement. To measure the latter, a setup that is based on a Michelson interferometer is used. To avoid the phenomenon of speckle and the drawbacks inherent to it, we use a light emitting diode as the light source for the interferometer. The detector is a visible CCD camera that analyzes the optical signal containing the information of surface displacement of the device. Combining images, we extract the amplitude of the surface displacement. Out-of-plane surface-displacement images of a thermoelectric device are presented

  12. Computer-Aided Panoramic Images Enriched by Shadow Construction on a Prism and Pyramid Polyhedral Surface

    Directory of Open Access Journals (Sweden)

    Jolanta Dzwierzynska

    2017-10-01

    Full Text Available The aim of this study is to develop an efficient and practical method of a direct mapping of a panoramic projection on an unfolded prism and pyramid polyhedral projection surface with the aid of a computer. Due to the fact that straight lines very often appear in any architectural form we formulate algorithms which utilize data about lines and draw panoramas as plots of functions in Mathcad software. The ability to draw panoramic images of lines enables drawing a wireframe image of an architectural object. The application of the multicenter projection, as well as the idea of shadow construction in the panoramic representation, aims at achieving a panoramic image close to human perception. The algorithms are universal as the application of changeable base elements of panoramic projection—horizon height, station point location, number of polyhedral walls—enables drawing panoramic images from various viewing positions. However, for more efficient and easier drawing, the algorithms should be implemented in some graphical package. The representation presented in the paper and the method of its direct mapping on a flat unfolded projection surface can find application in the presentation of architectural spaces in advertising and art when drawings are displayed on polyhedral surfaces and can be observed from multiple viewing positions.

  13. Color image quality in projection displays: a case study

    Science.gov (United States)

    Strand, Monica; Hardeberg, Jon Y.; Nussbaum, Peter

    2005-01-01

    Recently the use of projection displays has increased dramatically in different applications such as digital cinema, home theatre, and business and educational presentations. Even if the color image quality of these devices has improved significantly over the years, it is still a common situation for users of projection displays that the projected colors differ significantly from the intended ones. This study presented in this paper attempts to analyze the color image quality of a large set of projection display devices, particularly investigating the variations in color reproduction. As a case study, a set of 14 projectors (LCD and DLP technology) at Gjovik University College have been tested under four different conditions: dark and light room, with and without using an ICC-profile. To find out more about the importance of the illumination conditions in a room, and the degree of improvement when using an ICC-profile, the results from the measurements was processed and analyzed. Eye-One Beamer from GretagMacbeth was used to make the profiles. The color image quality was evaluated both visually and by color difference calculations. The results from the analysis indicated large visual and colorimetric differences between the projectors. Our DLP projectors have generally smaller color gamut than LCD projectors. The color gamuts of older projectors are significantly smaller than that of newer ones. The amount of ambient light reaching the screen is of great importance for the visual impression. If too much reflections and other ambient light reaches the screen, the projected image gets pale and has low contrast. When using a profile, the differences in colors between the projectors gets smaller and the colors appears more correct. For one device, the average ΔE*ab color difference when compared to a relative white reference was reduced from 22 to 11, for another from 13 to 6. Blue colors have the largest variations among the projection displays and makes them

  14. Calibrating AIS images using the surface as a reference

    Science.gov (United States)

    Smith, M. O.; Roberts, D. A.; Shipman, H. M.; Adams, J. B.; Willis, S. C.; Gillespie, A. R.

    1987-01-01

    A method of evaluating the initial assumptions and uncertainties of the physical connection between Airborne Imaging Spectrometer (AIS) image data and laboratory/field spectrometer data was tested. The Tuscon AIS-2 image connects to lab reference spectra by an alignment to the image spectral endmembers through a system gain and offset for each band. Images were calibrated to reflectance so as to transform the image into a measure that is independent of the solar radiant flux. This transformation also makes the image spectra directly comparable to data from lab and field spectrometers. A method was tested for calibrating AIS images using the surface as a reference. The surface heterogeneity is defined by lab/field spectral measurements. It was found that the Tuscon AIS-2 image is consistent with each of the initial hypotheses: (1) that the AIS-2 instrument calibration is nearly linear; (2) the spectral variance is caused by sub-pixel mixtures of spectrally distinct materials and shade, and (3) that sub-pixel mixtures can be treated as linear mixtures of pure endmembers. It was also found that the image can be characterized by relatively few endmembers using the AIS-2 spectra.

  15. Visual tritium imaging of In-Vessel surfaces

    International Nuclear Information System (INIS)

    Gentile, C. A.; Zweben, S. J.; Skinner, C. H.; Young, K. M.; Langish, S. W.; Nishi, M. F.; Shu, W. M.; Parker, J.; Isobe, K.

    2000-01-01

    A imaging detector has been developed for the purpose of providing a non-destructive, real time method of determining tritium concentrations on the surface of internal TFTR vacuum vessel components. The detector employs a green phosphor screen (P31, zinc sulfide: copper) with a wave length peak of 530 nm, a charge-coupled device (CCD) camera linked to a computer, and a detection chamber for inserting components recovered from the vacuum vessel. This detector is capable of determining tritium concentrations on the surfaces. The detector provides a method of imaging tritium deposition on the surfaces in a fairly rapid fashion

  16. Visual tritium imaging of in-vessel surfaces

    International Nuclear Information System (INIS)

    Gentile, C.A.; Zweben, S.J.; Skinner, C.H.; Young, K.M.; Langish, S.W.; Nishi, M.F.; Shu, W.M.; Parker, J.; Isobe, K.

    2000-01-01

    An imaging detector has been developed for the purpose of providing a non-destructive, real time method of determining tritium concentrations on the surface of internal TFTR vacuum vessel components. The detector employs a green phosphor screen (P31, zinc sulfide: copper) with a wave length peak of 530 nm, a charge-coupled device (CCD) camera linked to a computer, and a detection chamber for inserting components recovered from the vacuum vessel. This detector is capable of determining tritium concentrations on the surfaces. The detector provides a method of imaging tritium deposition on the surfaces in a fairly rapid fashion

  17. Thin plate spline feature point matching for organ surfaces in minimally invasive surgery imaging

    Science.gov (United States)

    Lin, Bingxiong; Sun, Yu; Qian, Xiaoning

    2013-03-01

    Robust feature point matching for images with large view angle changes in Minimally Invasive Surgery (MIS) is a challenging task due to low texture and specular reflections in these images. This paper presents a new approach that can improve feature matching performance by exploiting the inherent geometric property of the organ surfaces. Recently, intensity based template image tracking using a Thin Plate Spline (TPS) model has been extended for 3D surface tracking with stereo cameras. The intensity based tracking is also used here for 3D reconstruction of internal organ surfaces. To overcome the small displacement requirement of intensity based tracking, feature point correspondences are used for proper initialization of the nonlinear optimization in the intensity based method. Second, we generate simulated images from the reconstructed 3D surfaces under all potential view positions and orientations, and then extract feature points from these simulated images. The obtained feature points are then filtered and re-projected to the common reference image. The descriptors of the feature points under different view angles are stored to ensure that the proposed method can tolerate a large range of view angles. We evaluate the proposed method with silicon phantoms and in vivo images. The experimental results show that our method is much more robust with respect to the view angle changes than other state-of-the-art methods.

  18. 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.

  19. 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)

  20. IDENTIFYING SURFACE CHANGES ON HRSC IMAGES OF THE MARS SOUTH POLAR RESIDUAL CAP (SPRC

    Directory of Open Access Journals (Sweden)

    A. R. D. Putri

    2016-06-01

    Orthorectified Images (ORIs and projected into polar stereographic projection using DLR (Deutsches Zentrum für Luft- und Raumfahrt; German Aerospace Center’s VICAR and GIS software with modifications developed by Kim & Muller (2009. Surface changes are identified in the Mars SPRC region and analysed based on their appearance in the HRSC images.

  1. Scanning tunnelling microscope imaging of nanoscale electron density gradients on the surface of GaAs

    International Nuclear Information System (INIS)

    Hamilton, B; Jacobs, J; Missous, M

    2003-01-01

    This paper is concerned with the scanning tunnelling microscope tunnelling conditions needed to produce constant current images dominated either by surface topology or by electronic effects. A model experimental structure was produced by cleaving a GaAs multiδ-doped layer in UHV and so projecting a spatially varying electron gas density onto the (110) surface. This cross sectional electron density varies on a nanometre scale in the [100] growth direction. The electronic structure and tunnelling properties of this system were modelled, and the tunnelling conditions favouring sensitivity to the surface electron gas density determined

  2. Comparison of power spectra for tomosynthesis projections and reconstructed images

    International Nuclear Information System (INIS)

    Engstrom, Emma; Reiser, Ingrid; Nishikawa, Robert

    2009-01-01

    Burgess et al. [Med. Phys. 28, 419-437 (2001)] showed that the power spectrum of mammographic breast background follows a power law and that lesion detectability is affected by the power-law exponent β which measures the amount of structure in the background. Following the study of Burgess et al., the authors measured and compared the power-law exponent of mammographic backgrounds in tomosynthesis projections and reconstructed slices to investigate the effect of tomosynthesis imaging on background structure. Our data set consisted of 55 patient cases. For each case, regions of interest (ROIs) were extracted from both projection images and reconstructed slices. The periodogram of each ROI was computed by taking the squared modulus of the Fourier transform of the ROI. The power-law exponent was determined for each periodogram and averaged across all ROIs extracted from all projections or reconstructed slices for each patient data set. For the projections, the mean β averaged across the 55 cases was 3.06 (standard deviation of 0.21), while it was 2.87 (0.24) for the corresponding reconstructions. The difference in β for a given patient between the projection ROIs and the reconstructed ROIs averaged across the 55 cases was 0.194, which was statistically significant (p<0.001). The 95% CI for the difference between the mean value of β for the projections and reconstructions was [0.170, 0.218]. The results are consistent with the observation that the amount of breast structure in the tomosynthesis slice is reduced compared to projection mammography and that this may lead to improved lesion detectability.

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

    DEFF Research Database (Denmark)

    Zenker, Sebastian; Beckmann, Suzanne C.

    2013-01-01

    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......, 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...

  4. Projection model for flame chemiluminescence tomography based on lens imaging

    Science.gov (United States)

    Wan, Minggang; Zhuang, Jihui

    2018-04-01

    For flame chemiluminescence tomography (FCT) based on lens imaging, the projection model is essential because it formulates the mathematical relation between the flame projections captured by cameras and the chemiluminescence field, and, through this relation, the field is reconstructed. This work proposed the blurry-spot (BS) model, which takes more universal assumptions and has higher accuracy than the widely applied line-of-sight model. By combining the geometrical camera model and the thin-lens equation, the BS model takes into account perspective effect of the camera lens; by combining ray-tracing technique and Monte Carlo simulation, it also considers inhomogeneous distribution of captured radiance on the image plane. Performance of these two models in FCT was numerically compared, and results showed that using the BS model could lead to better reconstruction quality in wider application ranges.

  5. Fractal Image Coding Based on a Fitting Surface

    Directory of Open Access Journals (Sweden)

    Sheng Bi

    2014-01-01

    Full Text Available A no-search fractal image coding method based on a fitting surface is proposed. In our research, an improved gray-level transform with a fitting surface is introduced. One advantage of this method is that the fitting surface is used for both the range and domain blocks and one set of parameters can be saved. Another advantage is that the fitting surface can approximate the range and domain blocks better than the previous fitting planes; this can result in smaller block matching errors and better decoded image quality. Since the no-search and quadtree techniques are adopted, smaller matching errors also imply less number of blocks matching which results in a faster encoding process. Moreover, by combining all the fitting surfaces, a fitting surface image (FSI is also proposed to speed up the fractal decoding. Experiments show that our proposed method can yield superior performance over the other three methods. Relative to range-averaged image, FSI can provide faster fractal decoding process. Finally, by combining the proposed fractal coding method with JPEG, a hybrid coding method is designed which can provide higher PSNR than JPEG while maintaining the same Bpp.

  6. Superior MR images with electronically tuned and decoupled surface coils

    International Nuclear Information System (INIS)

    Ingwersen, H.; Freisen, L.; Friedrich, A.; Kess, H.; Krause, N.; Meissner, R.; Popp, W.

    1987-01-01

    In order to gain free positioning of surface coils in linearly polarized transmitting coils, it is absolutely necessary to electronically decouple both coils. For circularly polarized transmitting coils, decoupling is necessary in any case. In addition to the decoupling circuit automatic electronic tuning of the surface coils is used to gain the bast ratio of signal to noise. This combination of electronically decoupling and tuning of the surface coils yields intrinsic patient safety concerning local power deposition as well as free positioning and easy handling at the same time. Block diagrams, circuit schemes, and MR images obtained with several different surface coils are shown

  7. 3D fingerprint imaging system based on full-field fringe projection profilometry

    Science.gov (United States)

    Huang, Shujun; Zhang, Zonghua; Zhao, Yan; Dai, Jie; Chen, Chao; Xu, Yongjia; Zhang, E.; Xie, Lili

    2014-01-01

    As an unique, unchangeable and easily acquired biometrics, fingerprint has been widely studied in academics and applied in many fields over the years. The traditional fingerprint recognition methods are based on the obtained 2D feature of fingerprint. However, fingerprint is a 3D biological characteristic. The mapping from 3D to 2D loses 1D information and causes nonlinear distortion of the captured fingerprint. Therefore, it is becoming more and more important to obtain 3D fingerprint information for recognition. In this paper, a novel 3D fingerprint imaging system is presented based on fringe projection technique to obtain 3D features and the corresponding color texture information. A series of color sinusoidal fringe patterns with optimum three-fringe numbers are projected onto a finger surface. From another viewpoint, the fringe patterns are deformed by the finger surface and captured by a CCD camera. 3D shape data of the finger can be obtained from the captured fringe pattern images. This paper studies the prototype of the 3D fingerprint imaging system, including principle of 3D fingerprint acquisition, hardware design of the 3D imaging system, 3D calibration of the system, and software development. Some experiments are carried out by acquiring several 3D fingerprint data. The experimental results demonstrate the feasibility of the proposed 3D fingerprint imaging system.

  8. Digital image processing: Cylindrical surface plane development of CAREM fuel pellets

    International Nuclear Information System (INIS)

    Caccavelli, J; Cativa Tolosa, S; Gommes, C

    2012-01-01

    As part of the development of fuel pellets (FPs) for nuclear reactor CAREM-25, is necessary to systematize the analysis of the mechanical integrity of the FPs that is now done manually by a human operator. Following specifications and standards of reference for this purpose, the FPs should be inspected visually for detecting material discontinuities in the FPs surfaces to minimize any deterioration, loss of material and excessive breakage during operation and load of fuel bars. The material discontinuities are classified into two defects: surface cracks and chips. For each of these surface defects exist acceptance criteria that determine if the fuel pellet (FP) as a whole is accepted or rejected. One criteria for surface cracks is that they do not exceed one third (1/3) of the circumferential surface of the FP. The FP has cylindrical shape, so some of these acceptance criteria make difficult to analyze the FP in a single photographic image. Depending on the axial rotation of the FP, the crack could not be entirely visualized on the picture frame. Even a single crack that appears in different parts of the FP rotated images may appear to be different cracks in the FP when it is actually one. For this reason it is necessary, for the automatic detection and measurement of surface defects, obtain the circumferential surface of the FP into a single image in order to decide the acceptance or reject of the FP. As the FP shape is cylindrical, it is possible to obtain the flat development of the cylindrical surface (surface unrolling) of the FPs into a single image combining the image set of the axial rotation of the FP. In this work, we expose the procedure to implement the flat development of the cylindrical surface (surface unrolling). Starting from a photographic image of the FP surface, which represents the projection of a cylinder in the plane, we obtain three-dimensional information of each point on the cylindrical surface of the FP (3D-mapping). Then, we can

  9. Time-dependent image potential at a metal surface

    International Nuclear Information System (INIS)

    Alducin, M.; Diez Muino, R.; Juaristi, J.I.

    2003-01-01

    Transient effects in the image potential induced by a point charge suddenly created in front of a metal surface are studied. The time evolution of the image potential is calculated using linear response theory. Two different time scales are defined: (i) the time required for the creation of the image potential and (ii) the time it takes to converge to its stationary value. Their dependence on the distance of the charge to the surface is discussed. The effect of the electron gas damping is also analyzed. For a typical metallic density, the order of magnitude of the creation time is 0.1 fs, whereas for a charge created close to the surface the convergence time is around 1-2 fs

  10. Image Reconstruction and Evaluation: Applications on Micro-Surfaces and Lenna Image Representation

    Directory of Open Access Journals (Sweden)

    Mohammad Mayyas

    2016-09-01

    Full Text Available This article develops algorithms for the characterization and the visualization of micro-scale features using a small number of sample points, with the goal of mitigating the measurement shortcomings, which are often destructive or time consuming. The popular measurement techniques that are used in imaging of micro-surfaces include the 3D stylus or interferometric profilometry and Scanning Electron Microscopy (SEM, where both could represent the micro-surface characteristics in terms of 3D dimensional topology and greyscale image, respectively. Such images could be highly dense; therefore, traditional image processing techniques might be computationally expensive. We implement the algorithms in several case studies to rapidly examine the microscopic features of micro-surface of Microelectromechanical System (MEMS, and then we validate the results using a popular greyscale image; i.e., “Lenna” image. The contributions of this research include: First, development of local and global algorithm based on modified Thin Plate Spline (TPS model to reconstruct high resolution images of the micro-surface’s topography, and its derivatives using low resolution images. Second, development of a bending energy algorithm from our modified TPS model for filtering out image defects. Finally, development of a computationally efficient technique, referred to as Windowing, which combines TPS and Linear Sequential Estimation (LSE methods, to enhance the visualization of images. The Windowing technique allows rapid image reconstruction based on the reduction of inverse problem.

  11. Surfaced-based investigations plan, Volume 4: Yucca Mountain Project

    International Nuclear Information System (INIS)

    1988-12-01

    This document represents a detailed summary of design plans for surface-based investigations to be conducted for site characterization of the Yucca Mountain site. These plans are current as of December 1988. The description of surface-based site characterization activities contained in this document is intended to give all interested parties an understanding of the current plans for site characterization of Yucca Mountain. The maps presented in Volume 4 are products of the Geographic Information System (GIS) being used by the Yucca Mountain Project. The ARC/INFO GIS software, developed by Environmental Systems Research Institute, was used to digitize and process these SBIP maps. The maps were prepared using existing US Geological Survey (USGS) maps as a planimetric base. Roads and other surface features were interpreted from a variety of sources and entered into the GIS. Sources include the USGS maps, 1976 USGS orthophotoquads and aerial photography, 1986 and 1987 aerial photography, surveyed coordinates of field sites, and a combination of various maps, figures, descriptions and approximate coordinates of proposed locations for future activities

  12. Superresolution Near-field Imaging with Surface Waves

    KAUST Repository

    Fu, Lei

    2017-10-21

    We present the theory for near-field superresolution imaging with surface waves and time reverse mirrors (TRMs). Theoretical formulas and numerical results show that applying the TRM operation to surface waves in an elastic half-space can achieve superresolution imaging of subwavelength scatterers if they are located less than about 1/2 of the shear wavelength from the source line. We also show that the TRM operation for a single frequency is equivalent to natural migration, which uses the recorded data to approximate the Green’s functions for migration, and only costs O(N4) algebraic operations for poststack migration compared to O(N6) operations for natural prestack migration. Here, we assume the sources and receivers are on an N × N grid and there are N2 trial image points on the free surface. Our theoretical predictions of superresolution are validated with tests on synthetic data. The field-data tests suggest that hidden faults at the near surface can be detected with subwavelength imaging of surface waves by using the TRM operation if they are no deeper than about 1/2 the dominant shear wavelength.

  13. Determining Surface Infiltration Rate of Permeable Pavements with Digital Imaging

    Directory of Open Access Journals (Sweden)

    Caterina Valeo

    2018-01-01

    Full Text Available Cell phone images of pervious pavement surfaces were used to explore relationships between surface infiltration rates (SIR measured using the ASTM C1701 standard test and using a simple falling head test. A fiber-reinforced porous asphalt surface and a highly permeable material comprised of stone, rubber and a polymer binder (Porous Pave were tested. Images taken with a high-resolution cellphone camera were acquired as JPEG files and converted to gray scale images in Matlab® for analysis. The distribution of gray levels was compared to the surface infiltration rates obtained for both pavements with attention given to the mean of the distribution. Investigation into the relationships between mean SIR and parameters determined from the gray level distribution produced in the image analysis revealed that mean SIR measured in both pavements were proportional to the inverse of the mean of the distribution. The relationships produced a coefficient of determination over 85% using both the ASTM and the falling head test in the porous asphalt surface. SIR measurements determined with the ASTM method were highly correlated with the inverse mean of the distribution of gray levels in the Porous Pave material as well, producing coefficients of determination of over 90% and Kendall’s tau-b of roughly 70% for nonparametric data.

  14. STM Imaging of Localized Surface Plasmons on Individual Gold Nanoislands.

    Science.gov (United States)

    Nguyen, Huy A; Banerjee, Progna; Nguyen, Duc; Lyding, Joseph W; Gruebele, Martin; Jain, Prashant K

    2018-04-19

    An optically modulated scanning tunneling microscopy technique developed for measurement of single-molecule optical absorption is used here to image the light absorption by individual Au nanoislands and Au nanostructures. The technique is shown to spatially map, with nanometer resolution, localized surface plasmons (LSPs) excited within the nanoislands. Electrodynamic simulations demonstrate the correspondence of the measured images to plasmonic near-field intensity maps. The optical STM imaging technique captures the wavelength, polarization, and geometry dependence of the LSP resonances and their corresponding near-fields. Thus, we introduce a tool for real-space, nanometer-scale visualization of optical energy absorption, transport, and dissipation in complex plasmonic nanostructures.

  15. Surface Nuclear Magnetic Resonance Imaging of Large Systems

    International Nuclear Information System (INIS)

    Weichman, P.B.; Lavely, E.M.; Ritzwoller, M.H.

    1999-01-01

    The general theory of surface NMR imaging of large electromagnetically active systems is considered, motivated by geophysical applications. A general imaging equation is derived for the NMR voltage response, valid for arbitrary transmitter and receiver loop geometry and arbitrary conductivity structure of the sample. When the conductivity grows to the point where the electromagnetic skin depth becomes comparable to the sample size, significant diffusive retardation effects occur that strongly affect the signal. Accounting for these now allows more accurate imaging than previously possible. It is shown that the time constant T 1 may in principle be inferred directly from the diffusive tail of the signal. copyright 1999 The American Physical Society

  16. Textural Analysis of Fatique Crack Surfaces: Image Pre-processing

    Directory of Open Access Journals (Sweden)

    H. Lauschmann

    2000-01-01

    Full Text Available For the fatique crack history reconstitution, new methods of quantitative microfractography are beeing developed based on the image processing and textural analysis. SEM magnifications between micro- and macrofractography are used. Two image pre-processing operatins were suggested and proved to prepare the crack surface images for analytical treatment: 1. Normalization is used to transform the image to a stationary form. Compared to the generally used equalization, it conserves the shape of brightness distribution and saves the character of the texture. 2. Binarization is used to transform the grayscale image to a system of thick fibres. An objective criterion for the threshold brightness value was found as that resulting into the maximum number of objects. Both methods were succesfully applied together with the following textural analysis.

  17. Breast EIT using a new projected image reconstruction method with multi-frequency measurements.

    Science.gov (United States)

    Lee, Eunjung; Ts, Munkh-Erdene; Seo, Jin Keun; Woo, Eung Je

    2012-05-01

    We propose a new method to produce admittivity images of the breast for the diagnosis of breast cancer using electrical impedance tomography(EIT). Considering the anatomical structure of the breast, we designed an electrode configuration where current-injection and voltage-sensing electrodes are separated in such a way that internal current pathways are approximately along the tangential direction of an array of voltage-sensing electrodes. Unlike conventional EIT imaging methods where the number of injected currents is maximized to increase the total amount of measured data, current is injected only twice between two pairs of current-injection electrodes attached along the circumferential side of the breast. For each current injection, the induced voltages are measured from the front surface of the breast using as many voltage-sensing electrodes as possible. Although this electrode configurational lows us to measure induced voltages only on the front surface of the breast,they are more sensitive to an anomaly inside the breast since such an injected current tends to produce a more uniform internal current density distribution. Furthermore, the sensitivity of a measured boundary voltage between two equipotential lines on the front surface of the breast is improved since those equipotential lines are perpendicular to the primary direction of internal current streamlines. One should note that this novel data collection method is different from those of other frontal plane techniques such as the x-ray projection and T-scan imaging methods because we do not get any data on the plane that is perpendicular to the current flow. To reconstruct admittivity images using two measured voltage data sets, a new projected image reconstruction algorithm is developed. Numerical simulations demonstrate the frequency-difference EIT imaging of the breast. The results show that the new method is promising to accurately detect and localize small anomalies inside the breast.

  18. Breast EIT using a new projected image reconstruction method with multi-frequency measurements

    International Nuclear Information System (INIS)

    Lee, Eunjung; Ts, Munkh-Erdene; Seo, Jin Keun; Woo, Eung Je

    2012-01-01

    We propose a new method to produce admittivity images of the breast for the diagnosis of breast cancer using electrical impedance tomography (EIT). Considering the anatomical structure of the breast, we designed an electrode configuration where current-injection and voltage-sensing electrodes are separated in such a way that internal current pathways are approximately along the tangential direction of an array of voltage-sensing electrodes. Unlike conventional EIT imaging methods where the number of injected currents is maximized to increase the total amount of measured data, current is injected only twice between two pairs of current-injection electrodes attached along the circumferential side of the breast. For each current injection, the induced voltages are measured from the front surface of the breast using as many voltage-sensing electrodes as possible. Although this electrode configuration allows us to measure induced voltages only on the front surface of the breast, they are more sensitive to an anomaly inside the breast since such an injected current tends to produce a more uniform internal current density distribution. Furthermore, the sensitivity of a measured boundary voltage between two equipotential lines on the front surface of the breast is improved since those equipotential lines are perpendicular to the primary direction of internal current streamlines. One should note that this novel data collection method is different from those of other frontal plane techniques such as the x-ray projection and T-scan imaging methods because we do not get any data on the plane that is perpendicular to the current flow. To reconstruct admittivity images using two measured voltage data sets, a new projected image reconstruction algorithm is developed. Numerical simulations demonstrate the frequency-difference EIT imaging of the breast. The results show that the new method is promising to accurately detect and localize small anomalies inside the breast. (paper)

  19. RGB color coded images in scanning electron microscopy of biological surfaces

    Czech Academy of Sciences Publication Activity Database

    Kofroňová, Olga; Benada, Oldřich

    2017-01-01

    Roč. 61, č. 3 (2017), s. 349-352 ISSN 0001-723X R&D Projects: GA MŠk(CZ) LO1509; GA ČR(CZ) GA16-20229S Institutional support: RVO:61388971 Keywords : Biological surfaces * Color image s * Scanning electron microscopy Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 0.673, year: 2016

  20. Surface and borehole electromagnetic imaging of conducting contaminant plumes. 1997 annual progress report

    International Nuclear Information System (INIS)

    Berryman, J.G.

    1997-01-01

    'Electromagnetic induction tomography is a promising new tool for imaging electrical conductivity variations in the earth. The EM source field is produced by induction coil (magnetic dipole) transmitters deployed at the surface or in boreholes. Vertical and horizontal component magnetic field detectors are deployed in other boreholes or on the surface. Sources and receivers are typically deployed in a configuration surrounding the region of interest. The goal of this procedure is to image electrical conductivity variations in the earth, much as x-ray tomography is used to image density variations through cross-sections of the body. Although such EM field techniques have been developed and applied, the algorithms for inverting the magnetic data to produce the desired images of electrical conductivity have not kept pace. One of the main reasons for the lag in the algorithm development has been the fact that the magnetic induction problem is inherently three dimensional: other imaging methods such as x-ray and seismic can make use of two-dimensional approximations that are not too far from reality, but the author does not have this luxury in EM induction tomography. In addition, previous field experiments were conducted at controlled test sites that typically do not have much external noise or extensive surface clutter problems often associated with environmental sites. To use the same field techniques in environments more typical of cleanup sites requires a new set of data processing tools to remove the effects of both noise and clutter. The goal of this project is to join theory and experiment to produce enhanced images of electrically conducting fluids underground, allowing better localization of contaminants and improved planning strategies for the subsequent remediation efforts. After explaining the physical context in more detail, this report will summarize the progress made in the first year of this project: (1) on code development and (2) on field tests of

  1. Ultrasonic phased array with surface acoustic wave for imaging cracks

    Directory of Open Access Journals (Sweden)

    Yoshikazu Ohara

    2017-06-01

    Full Text Available To accurately measure crack lengths, we developed a real-time surface imaging method (SAW PA combining an ultrasonic phased array (PA with a surface acoustic wave (SAW. SAW PA using a Rayleigh wave with a high sensitivity to surface defects was implemented for contact testing using a wedge with the third critical angle that allows the Rayleigh wave to be generated. Here, to realize high sensitivity imaging, SAW PA was optimized in terms of the wedge and the imaging area. The improved SAW PA was experimentally demonstrated using a fatigue crack specimen made of an aluminum alloy. For further verification in more realistic specimens, SAW PA was applied to stainless-steel specimens with a fatigue crack and stress corrosion cracks (SCCs. The fatigue crack was visualized with a high signal-to-noise ratio (SNR and its length was measured with a high accuracy of better than 1 mm. The SCCs generated in the heat-affected zones (HAZs of a weld were successfully visualized with a satisfactory SNR, although responses at coarse grains appeared throughout the imaging area. The SCC lengths were accurately measured. The imaging results also precisely showed complicated distributions of SCCs, which were in excellent agreement with the optically observed distributions.

  2. Accounting for free-surface multiples in Marchenko imaging

    NARCIS (Netherlands)

    Singh, S.; Snieder, R; van der Neut, J.R.; Thorbecke, J.W.; Slob, E.C.; Wapenaar, C.P.A.

    2017-01-01

    Imagine placing a receiver at any location in the earth and recording the response at that location to sources on the surface. In such a world, we could place receivers around our reservoir to better image the reservoir and understand its properties. Realistically, this is not a feasible approach

  3. Surface Reconstruction and Image Enhancement via $L^1$-Minimization

    KAUST Repository

    Dobrev, Veselin

    2010-01-01

    A surface reconstruction technique based on minimization of the total variation of the gradient is introduced. Convergence of the method is established, and an interior-point algorithm solving the associated linear programming problem is introduced. The reconstruction algorithm is illustrated on various test cases including natural and urban terrain data, and enhancement oflow-resolution or aliased images. Copyright © by SIAM.

  4. A Novel Algorithm of Surface Eliminating in Undersurface Optoacoustic Imaging

    Directory of Open Access Journals (Sweden)

    Zhulina Yulia V

    2004-01-01

    Full Text Available This paper analyzes the task of optoacoustic imaging of the objects located under the surface covering them. In this paper, we suggest the algorithm of the surface eliminating based on the fact that the intensity of the image as a function of the spatial point should change slowly inside the local objects, and will suffer a discontinuity of the spatial gradients on their boundaries. The algorithm forms the 2-dimensional curves along which the discontinuity of the signal derivatives is detected. Then, the algorithm divides the signal space into the areas along these curves. The signals inside the areas with the maximum level of the signal amplitudes and the maximal gradient absolute values on their edges are put equal to zero. The rest of the signals are used for the image restoration. This method permits to reconstruct the picture of the surface boundaries with a higher contrast than that of the surface detection technique based on the maximums of the received signals. This algorithm does not require any prior knowledge of the signals' statistics inside and outside the local objects. It may be used for reconstructing any images with the help of the signals representing the integral over the object's volume. Simulation and real data are also provided to validate the proposed method.

  5. Uranium Mill Tailings Remedial Action Project, Surface Project Management Plan. Revision 1

    International Nuclear Information System (INIS)

    1994-12-01

    Title I of the Uranium Mill Tailings Radiation Control Act (UMTRCA) authorizes the US Department of Energy (DOE) to undertake remedial action at 24 designated inactive uranium processing sites and associated vicinity properties (VP) containing uranium mill tailings and related residual radioactive materials. The purpose of the Uranium Mill Tailings Remedial Action (UMTRA) Surface Project is to minimize or eliminate radiation health hazards to the public and the environment at the 24 sites and related VPs. This document describes the management organization, system, and methods used to manage the design, construction, and other activities required to clean up the designated sites and associated VPs, in accordance with the UMTRCA

  6. Uranium Mill Tailings Remedial Action Project, Surface Project Management Plan. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-01

    Title I of the Uranium Mill Tailings Radiation Control Act (UMTRCA) authorizes the US Department of Energy (DOE) to undertake remedial action at 24 designated inactive uranium processing sites and associated vicinity properties (VP) containing uranium mill tailings and related residual radioactive materials. The purpose of the Uranium Mill Tailings Remedial Action (UMTRA) Surface Project is to minimize or eliminate radiation health hazards to the public and the environment at the 24 sites and related VPs. This document describes the management organization, system, and methods used to manage the design, construction, and other activities required to clean up the designated sites and associated VPs, in accordance with the UMTRCA.

  7. Investigation of synthetic aperture methods in ultrasound surface imaging using elementary surface types.

    Science.gov (United States)

    Kerr, W; Pierce, S G; Rowe, P

    2016-12-01

    Synthetic aperture imaging methods have been employed widely in recent research in non-destructive testing (NDT), but uptake has been more limited in medical ultrasound imaging. Typically offering superior focussing power over more traditional phased array methods, these techniques have been employed in NDT applications to locate and characterise small defects within large samples, but have rarely been used to image surfaces. A desire to ultimately employ ultrasonic surface imaging for bone surface geometry measurement prior to surgical intervention motivates this research, and results are presented for initial laboratory trials of a surface reconstruction technique based on global thresholding of ultrasonic 3D point cloud data. In this study, representative geometry artefacts were imaged in the laboratory using two synthetic aperture techniques; the Total Focusing Method (TFM) and the Synthetic Aperture Focusing Technique (SAFT) employing full and narrow synthetic apertures, respectively. Three high precision metallic samples of known geometries (cuboid, sphere and cylinder) which featured a range of elementary surface primitives were imaged using a 5MHz, 128 element 1D phased array employing both SAFT and TFM approaches. The array was manipulated around the samples using a precision robotic positioning system, allowing for repeatable ultrasound derived 3D surface point clouds to be created. A global thresholding technique was then developed that allowed the extraction of the surface profiles, and these were compared with the known geometry samples to provide a quantitative measure of error of 3D surface reconstruction. The mean errors achieved with optimised SAFT imaging for the cuboidal, spherical and cylindrical samples were 1.3mm, 2.9mm and 2.0mm respectively, while those for TFM imaging were 3.7mm, 3.0mm and 3.1mm, respectively. These results were contrary to expectations given the higher information content associated with the TFM images. However, it was

  8. 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

  9. Wear-less floating contact imaging of polymer surfaces

    International Nuclear Information System (INIS)

    Knoll, A; Rothuizen, H; Gotsmann, B; Duerig, U

    2010-01-01

    An atomic force microscopy (AFM) technique is described combining two operating modes that previously were mutually exclusive: gentle imaging of delicate surfaces requiring slow dynamic AFM techniques, and passive feedback contact mode AFM enabling ultra-fast imaging. A high-frequency force modulation is used to excite resonant modes in the MHz range of a highly compliant cantilever force sensor with a spring constant of 0.1 N m -1 . The high-order mode acts as a stiff system for modulating the tip-sample distance and a vibration amplitude of 1 nm is sufficient to overcome the adhesion interaction. The soft cantilever provides a force-controlled support for the vibrating tip, enabling high-speed intermittent contact force microscopy without feedback control of the cantilever bending. Using this technique, we were able to image delicate polymer surfaces and to completely suppress the formation of the ripple wear patterns that are commonly observed in contact AFM.

  10. Three dimensional imaging of surface geometry in SEM

    International Nuclear Information System (INIS)

    Slowko, W.

    1997-01-01

    A great advantage of scanning electron microscopy (SEM) is its ability of the surface topography in the way as a human eye is accustomed to see lights and shadows on macroobjects. However, SEM's can hardly display vertical dimensions of the structures. One of possible solutions is reconstruction of the surface profiles by directional detection of secondary electrons and proper signal processing. However, the surface profile still gives two dimensional information and the method should be extended to obtain fully three dimensional imaging. The extension consists in a simultaneous reconstruction of the surface profiles in two perpendicular directions (x and y) and their superposition. The solution proposed is based on a quadrupole detector system and a computer or analogue system for signal processing. Quantitative data of the surface topography can be displayed in many manners in the system of two or three co-ordinates with use of pseudo-colour for the altitude coding. (author)

  11. Diagnosis of Alzheimer's disease using brain SPECT with three-dimensional stereotactic surface projections

    International Nuclear Information System (INIS)

    Hanyu, Haruo; Asano, Tetsuichi; Kogure, Daiji; Abe, Shine; Iwamoto, Toshihiko; Takasaki, Masaru

    2001-01-01

    We compared the diagnostic usefulness of three-dimensional stereotactic surface projection (3D-SSP) with that of standard transaxial images in brain SPECT in patients with Alzheimer's disease (AD). The subjects consisted of 69 patients with AD and 60 patients with non-AD, including vascular dementia, Parkinson's disease with dementia, frontotemporal dementia, other dementing diseases and neuropsychiatric diseases. Standard transaxial section and 3D-SSP SPECT images with N-isopropyl-p-[ 123 I] iodoamphetamine were blindly interpreted by three examiners and were classified into the following three patterns: typical AD, atypical AD, and not indicative AD patterns. The 3D-SSP images demonstrated reductions of cerebral blood flow in the parieto-temporal association cortex and posterior cingulate gyrus more clearly and easily than the standard transaxial images. The diagnostic sensitivity and specificity were 93% and 85% with 3D-SSP and 83% and 82% with standard transaxial section respectively. 3D-SSP was especially useful for early or atypical AD which showed no characteristic perfusion abnormalities on standard transaxial images. These results suggest that SPECT with 3D-SSP provides an sensitive as well as accurate tool for the diagnosis of AD. (author)

  12. Detection of cracks on concrete surfaces by hyperspectral image processing

    Science.gov (United States)

    Santos, Bruno O.; Valença, Jonatas; Júlio, Eduardo

    2017-06-01

    All large infrastructures worldwide must have a suitable monitoring and maintenance plan, aiming to evaluate their behaviour and predict timely interventions. In the particular case of concrete infrastructures, the detection and characterization of crack patterns is a major indicator of their structural response. In this scope, methods based on image processing have been applied and presented. Usually, methods focus on image binarization followed by applications of mathematical morphology to identify cracks on concrete surface. In most cases, publications are focused on restricted areas of concrete surfaces and in a single crack. On-site, the methods and algorithms have to deal with several factors that interfere with the results, namely dirt and biological colonization. Thus, the automation of a procedure for on-site characterization of crack patterns is of great interest. This advance may result in an effective tool to support maintenance strategies and interventions planning. This paper presents a research based on the analysis and processing of hyper-spectral images for detection and classification of cracks on concrete structures. The objective of the study is to evaluate the applicability of several wavelengths of the electromagnetic spectrum for classification of cracks in concrete surfaces. An image survey considering highly discretized wavelengths between 425 nm and 950 nm was performed on concrete specimens, with bandwidths of 25 nm. The concrete specimens were produced with a crack pattern induced by applying a load with displacement control. The tests were conducted to simulate usual on-site drawbacks. In this context, the surface of the specimen was subjected to biological colonization (leaves and moss). To evaluate the results and enhance crack patterns a clustering method, namely k-means algorithm, is being applied. The research conducted allows to define the suitability of using clustering k-means algorithm combined with hyper-spectral images highly

  13. Imaging near-surface heterogeneities by natural migration of surface waves

    KAUST Repository

    Liu, Zhaolun

    2016-09-06

    We demonstrate that near-surface heterogeneities can be imaged by natural migration of backscattered surface waves in common shot gathers. No velocity model is required because the data are migrated onto surface points with the virtual Green\\'s functions computed from the shot gathers. Migrating shot gathers recorded by 2D and 3D land surveys validates the effectiveness of detecting nearsurface heterogeneities by natural migration. The implication is that more accurate hazard maps can be created by migrating surface waves in land surveys.

  14. 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.

  15. Image reconstruction from multiple fan-beam projections

    International Nuclear Information System (INIS)

    Jelinek, J.; Overton, T.R.

    1984-01-01

    Special-purpose third-generation fan-beam CT systems can be greatly simplified by limiting the number of detectors, but this requires a different mode of data collection to provide a set of projections appropriate to the required spatial resolution in the reconstructed image. Repeated rotation of the source-detector fan, combined with shift of the detector array and perhaps offset of the source with respect to the fan's axis after each 360 0 rotation(cycle), provides a fairly general pattern of projection space filling. The authors' investigated the problem of optimal data-collection geometry for a multiple-rotation fan-beam scanner and of corresponding reconstruction algorithm

  16. IMAGE CONSTRUCTION TO AUTOMATION OF PROJECTIVE TECHNIQUES FOR PSYCHOPHYSIOLOGICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Natalia Pavlova

    2018-04-01

    Full Text Available The search for a solution of automation of the process of assessment of a psychological analysis of the person drawings created by it from an available set of some templates are presented at this article. It will allow to reveal more effectively infringements of persons mentality. In particular, such decision can be used for work with children who possess the developed figurative thinking, but are not yet capable of an accurate statement of the thoughts and experiences. For automation of testing by using a projective method, we construct interactive environment for visualization of compositions of the several images and then analyse

  17. Imaging of Stellar Surfaces with the Navy Precision Optical Interferometer

    Science.gov (United States)

    Jorgensen, A.; Schmitt, H. R.; van Belle, G. T.; Hutter, Clark; Mozurkewich, D.; Armstrong, J. T.; Baines, E. K.; Restaino, S. R.

    The Navy Precision Optical Interferometer (NPOI) has a unique layout which is particularly well-suited for high-resolution interferometric imaging. By combining the NPOI layout with a new data acquisition and fringe tracking system we are progressing toward a imaging capability which will exceed any other interferometer in operation. The project, funded by the National Science Foundation, combines several existing advances and infrastructure at NPOI with modest enhancements. For optimal imaging there are several requirements that should be fulfilled. The observatory should be capable of measuring visibilities on a wide range of baseline lengths and orientations, providing complete UV coverage in a short period of time. It should measure visibility amplitudes with good SNR on all baselines as critical imaging information is often contained in low-amplitude visibilities. It should measure the visibility phase on all baselines. The technologies which can achieve this are the NPOI Y-shaped array with (nearly) equal spacing between telescopes and an ability for rapid configuration. Placing 6-telescopes in a row makes it possible to measure visibilities into the 4th lobe of the visibility function. By arranging the available telescopes carefully we will be able to switch, every few days, between 3 different 6-station chains which provide symmetric coverage in the UV (Fourier) plane without moving any telescopes, only by moving beam relay mirrors. The 6-station chains are important to achieve the highest imaging resolution, and switching rapidly between station chains provides uniform coverage. Coherent integration techniques can be used to obtain good SNR on very small visibilities. Coherently integrated visibilities can be used for imaging with standard radio imaging packages such as AIPS. The commissioning of one additional station, the use of new data acquisition hardware and fringe tracking algorithms are the enhancements which make this project possible.

  18. Preliminary Study on Earthquake Surface Rupture Extraction from Uav Images

    Science.gov (United States)

    Yuan, X.; Wang, X.; Ding, X.; Wu, X.; Dou, A.; Wang, S.

    2018-04-01

    Because of the advantages of low-cost, lightweight and photography under the cloud, UAVs have been widely used in the field of seismic geomorphology research in recent years. Earthquake surface rupture is a typical seismic tectonic geomorphology that reflects the dynamic and kinematic characteristics of crustal movement. The quick identification of earthquake surface rupture is of great significance for understanding the mechanism of earthquake occurrence, disasters distribution and scale. Using integrated differential UAV platform, series images were acquired with accuracy POS around the former urban area (Qushan town) of Beichuan County as the area stricken seriously by the 2008 Wenchuan Ms8.0 earthquake. Based on the multi-view 3D reconstruction technique, the high resolution DSM and DOM are obtained from differential UAV images. Through the shade-relief map and aspect map derived from DSM, the earthquake surface rupture is extracted and analyzed. The results show that the surface rupture can still be identified by using the UAV images although the time of earthquake elapse is longer, whose middle segment is characterized by vertical movement caused by compression deformation from fault planes.

  19. Spectrally enhanced image resolution of tooth enamel surfaces

    Science.gov (United States)

    Zhang, Liang; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

    2012-01-01

    Short-wavelength 405 nm laser illumination of surface dental enamel using an ultrathin scanning fiber endoscope (SFE) produced enhanced detail of dental topography. The surfaces of human extracted teeth and artificial erosions were imaged with 405 nm, 444 nm, 532 nm, or 635 nm illumination lasers. The obtained images were then processed offline to compensate for any differences in the illumination beam diameters between the different lasers. Scattering and absorption coefficients for a Monte Carlo model of light propagation in dental enamel for 405 nm were scaled from published data at 532 nm and 633 nm. The value of the scattering coefficient used in the model was scaled from the coefficients at 532 nm and 633 nm by the inverse third power of wavelength. Simulations showed that the penetration depth of short-wavelength illumination is localized close to the enamel surface, while long-wavelength illumination travels much further and is backscattered from greater depths. Therefore, images obtained using short wavelength laser are not contaminated by the superposition of light reflected from enamel tissue at greater depths. Hence, the SFE with short-wavelength illumination may make it possible to visualize surface manifestations of phenomena such as demineralization, thus better aiding the clinician in the detection of early caries.

  20. A monthly quality assurance procedure for 3D surface imaging.

    Science.gov (United States)

    Wooten, H Omar; Klein, Eric E; Gokhroo, Garima; Santanam, Lakshmi

    2010-12-21

    A procedure for periodic quality assurance of a video surface imaging system is introduced. AlignRT is a video camera-based patient localization system that captures and compares images of a patient's topography to a DICOM-formatted external contour, then calculates shifts required to accurately reposition the patient. This technical note describes the tools and methods implemented in our department to verify correct and accurate operation of the AlignRT hardware and software components. The procedure described is performed monthly and complements a daily calibration of the system.

  1. An electron tomography algorithm for reconstructing 3D morphology using surface tangents of projected scattering interfaces

    Science.gov (United States)

    Petersen, T. C.; Ringer, S. P.

    2010-03-01

    Upon discerning the mere shape of an imaged object, as portrayed by projected perimeters, the full three-dimensional scattering density may not be of particular interest. In this situation considerable simplifications to the reconstruction problem are possible, allowing calculations based upon geometric principles. Here we describe and provide an algorithm which reconstructs the three-dimensional morphology of specimens from tilt series of images for application to electron tomography. Our algorithm uses a differential approach to infer the intersection of projected tangent lines with surfaces which define boundaries between regions of different scattering densities within and around the perimeters of specimens. Details of the algorithm implementation are given and explained using reconstruction calculations from simulations, which are built into the code. An experimental application of the algorithm to a nano-sized Aluminium tip is also presented to demonstrate practical analysis for a real specimen. Program summaryProgram title: STOMO version 1.0 Catalogue identifier: AEFS_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEFS_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 2988 No. of bytes in distributed program, including test data, etc.: 191 605 Distribution format: tar.gz Programming language: C/C++ Computer: PC Operating system: Windows XP RAM: Depends upon the size of experimental data as input, ranging from 200 Mb to 1.5 Gb Supplementary material: Sample output files, for the test run provided, are available. Classification: 7.4, 14 External routines: Dev-C++ ( http://www.bloodshed.net/devcpp.html) Nature of problem: Electron tomography of specimens for which conventional back projection may fail and/or data for which there is a limited angular

  2. Surface Projection of Interosseous Foramen of the Leg: Cadaver Study

    Directory of Open Access Journals (Sweden)

    Eric Arguello

    2016-01-01

    Full Text Available Purpose. This study was conducted to identify the surface projection of the interosseous foramen and associated structures of the proximal leg using the average clinician’s thumb width as a quick measurement to assist in differential diagnosis and treatment. Methods. Twelve cadavers (5 males and 7 females, age range = 51–91 years, and mean age = 76.9 were dissected for analysis. Location and size of interosseous foramen, location of anterior tibial artery, location of deep fibular nerve, and corresponding arterial branches were measured and converted into thumb widths. Results. Mean thumb width measured among the cadavers was 17.94±3.9 mm. The interosseous foramen measured was approximately 1 thumb width vertically (18.47±3.0 mm and 1/2 thumb width horizontally (7.32±2.1 mm and was located approximately 1 thumb width distally to the tibial tuberosity (20.81±6.8 mm and 2 thumb widths (37.47±4.7 mm lateral to the tibial ridge. The anterior tibial artery and deep fibular nerve converged approximately 4 thumb widths (74.31±14.8 mm inferior to the tibial tuberosity and 2 thumb widths (33.46±4.9 mm lateral to the tibial ridge. Conclusion. Clinicians may identify anatomical structures of the proximal leg with palpation using the thumb width for measurement.

  3. Planetary surface photometry and imaging: progress and perspectives.

    Science.gov (United States)

    Goguen, Jay D

    2014-10-01

    Spacecraft have visited and returned many thousands of images and spectra of all of the planets, many of their moons, several asteroids, and a few comet nuclei during the golden age of planetary exploration. The signal in each pixel of each image or spectral channel is a measurement of the radiance of scattered sunlight into a specific direction. The information on the structure and composition of the surface that is contained in variation of the radiance with scattering geometry and wavelength, including polarization state, has only just begun to be exploited and is the topic of this review. The uppermost surfaces of these bodies are mainly composed of particles that are continuously generated by impacts of micrometeoroids and larger impactors. Models of light scattering by distributions of sizes and irregular shapes of particles and by closely packed particles within a surface are challenging. These are active topics of research where considerable progress has recently been made. We focus on the surfaces of bodies lacking atmospheres.These surfaces are diverse and their morphologies give evidence of their evolution by impacts and resurfacing by a variety of processes including down slope movement and electrostatic transport of particles, gravitational accumulation of debris, volatile outgassing and migration, and magnetospheric interactions. Sampling of scattering geometries and spatial resolution is constrained by spacecraft trajectories. However, the large number of archived images and spectra demand more quantitative interpretation. The scattering geometry dependence of the radiance is underutilized and promises constraints on the compositions and structure of the surface for materials that lack diagnostic wavelength dependence. The general problem is considered in terms of the lunar regolith for which samples have been returned to Earth.

  4. Localized surface plasmon enhanced cellular imaging using random metallic structures

    Science.gov (United States)

    Son, Taehwang; Lee, Wonju; Kim, Donghyun

    2017-02-01

    We have studied fluorescence cellular imaging with randomly distributed localized near-field induced by silver nano-islands. For the fabrication of nano-islands, a 10-nm silver thin film evaporated on a BK7 glass substrate with an adhesion layer of 2-nm thick chromium. Micrometer sized silver square pattern was defined using e-beam lithography and then the film was annealed at 200°C. Raw images were restored using electric field distribution produced on the surface of random nano-islands. Nano-islands were modeled from SEM images. 488-nm p-polarized light source was set to be incident at 60°. Simulation results show that localized electric fields were created among nano-islands and that their average size was found to be 135 nm. The feasibility was tested using conventional total internal reflection fluorescence microscopy while the angle of incidence was adjusted to maximize field enhancement. Mouse microphage cells were cultured on nano-islands, and actin filaments were selectively stained with FITC-conjugated phalloidin. Acquired images were deconvolved based on linear imaging theory, in which molecular distribution was sampled by randomly distributed localized near-field and blurred by point spread function of far-field optics. The optimum fluorophore distribution was probabilistically estimated by repetitively matching a raw image. The deconvolved images are estimated to have a resolution in the range of 100-150 nm largely determined by the size of localized near-fields. We also discuss and compare the results with images acquired with periodic nano-aperture arrays in various optical configurations to excite localized plasmonic fields and to produce super-resolved molecular images.

  5. A Photometric Stereo Using Re-Projected Images for Active Stereo Vision System

    Directory of Open Access Journals (Sweden)

    Keonhwa Jung

    2017-10-01

    Full Text Available In optical 3D shape measurement, stereo vision with structured light can measure 3D scan data with high accuracy and is used in many applications, but fine surface detail is difficult to obtain. On the other hand, photometric stereo can capture surface details but has disadvantages, in that its 3D data accuracy drops and it requires multiple light sources. When the two measurement methods are combined, more accurate 3D scan data and detailed surface features can be obtained at the same time. In this paper, we present a 3D optical measurement technique that uses re-projection of images to implement photometric stereo without an external light source. 3D scan data is enhanced by combining normal vector from this photometric stereo method, and the result is evaluated with the ground truth.

  6. Nonnegative least-squares image deblurring: improved gradient projection approaches

    Science.gov (United States)

    Benvenuto, F.; Zanella, R.; Zanni, L.; Bertero, M.

    2010-02-01

    The least-squares approach to image deblurring leads to an ill-posed problem. The addition of the nonnegativity constraint, when appropriate, does not provide regularization, even if, as far as we know, a thorough investigation of the ill-posedness of the resulting constrained least-squares problem has still to be done. Iterative methods, converging to nonnegative least-squares solutions, have been proposed. Some of them have the 'semi-convergence' property, i.e. early stopping of the iteration provides 'regularized' solutions. In this paper we consider two of these methods: the projected Landweber (PL) method and the iterative image space reconstruction algorithm (ISRA). Even if they work well in many instances, they are not frequently used in practice because, in general, they require a large number of iterations before providing a sensible solution. Therefore, the main purpose of this paper is to refresh these methods by increasing their efficiency. Starting from the remark that PL and ISRA require only the computation of the gradient of the functional, we propose the application to these algorithms of special acceleration techniques that have been recently developed in the area of the gradient methods. In particular, we propose the application of efficient step-length selection rules and line-search strategies. Moreover, remarking that ISRA is a scaled gradient algorithm, we evaluate its behaviour in comparison with a recent scaled gradient projection (SGP) method for image deblurring. Numerical experiments demonstrate that the accelerated methods still exhibit the semi-convergence property, with a considerable gain both in the number of iterations and in the computational time; in particular, SGP appears definitely the most efficient one.

  7. Remote Imaging Projects In Research And Astrophotography With Starpals

    Science.gov (United States)

    Fischer, Audrey; Kingan, J.

    2008-05-01

    StarPals is a nascent non-profit organization with the goal of providing opportunities for international collaboration between students of all ages within space science research. We believe that by encouraging an interest in the cosmos, the one thing that is truly Universal, from a young age, students will not only further their knowledge of and interest in science but will learn valuable teamwork and life skills. The goal is to foster respect, understanding and appreciation of cultural diversity among all StarPals participants, whether students, teachers, or mentors. StarPals aims to inspire students by providing opportunities in which, more than simply visualizing themselves as research scientists, they can actually become one. The technologies of robotic telescopes, videoconferencing, and online classrooms are expanding the possibilities like never before. In honor of IYA2009, StarPals would like to encourage 400 schools to participate on a global scale in astronomy/cosmology research on various concurrent projects. We will offer in-person or online workshops and training sessions to teach the teachers. We will be seeking publication in scientific journals for some student research. For our current project, the Double Stars Challenge, students use the robotic telescopes to take a series of four images of one of 30 double stars from a list furnished by the US Naval Observatory and then use MPO Canopus software to take distance and position angle measurements. StarPals provides students with hands-on training, telescope time, and software to complete the imaging and measuring. A paper will be drafted from our research data and submitted to the Journal of Double Star Observations. The kids who participate in this project may potentially be the youngest contributors to an article in a vetted scientific journal. Kids rapidly adapt and improve their computer skills operating these telescopes and discover for themselves that science is COOL!

  8. 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

  9. 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.

  10. Image-potential states on the metallic (111) surface of bismuth

    International Nuclear Information System (INIS)

    Muntwiler, Matthias; Zhu, X-Y

    2008-01-01

    An extended series (up to n=6, in quantum beats) of image-potential states (IPS) is observed in time-resolved two-photon photoelectron (TR-2PPE) spectroscopy of the Bi(111) surface. Although mainly located in the vacuum, these states probe various properties of the electronic structure of the surface as reflected in their energetics and dynamics. Based on the observation of IPS a projected gap in the surface normal direction is inferred in the region from 3.57 to 4.27 eV above the Fermi level. Despite this band gap, the lifetimes of the IPS are shorter than on comparable metals, which is an indication of the metallic character of the Bi(111) surface.

  11. Metal surface corrosion grade estimation from single image

    Science.gov (United States)

    Chen, Yijun; Qi, Lin; Sun, Huyuan; Fan, Hao; Dong, Junyu

    2018-04-01

    Metal corrosion can cause many problems, how to quickly and effectively assess the grade of metal corrosion and timely remediation is a very important issue. Typically, this is done by trained surveyors at great cost. Assisting them in the inspection process by computer vision and artificial intelligence would decrease the inspection cost. In this paper, we propose a dataset of metal surface correction used for computer vision detection and present a comparison between standard computer vision techniques by using OpenCV and deep learning method for automatic metal surface corrosion grade estimation from single image on this dataset. The test has been performed by classifying images and calculating the accuracy for the two different approaches.

  12. Using IR Imaging of Water Surfaces for Estimating Piston Velocities

    Science.gov (United States)

    Gålfalk, M.; Bastviken, D.; Arneborg, L.

    2013-12-01

    The transport of gasses dissolved in surface waters across the water-atmosphere interface is controlled by the piston velocity (k). This coefficient has large implications for, e.g., greenhouse gas fluxes but is challenging to quantify in situ. At present, empirical k-wind speed relationships from a small number of studies and systems are often extrapolated without knowledge of model performance. It is therefore of interest to search for new methods for estimating k, and to compare the pros and cons of existing and new methods. Wind speeds in such models are often measured at a height of 10 meters. In smaller bodies of water such as lakes, wind speeds can vary dramatically across the surface through varying degrees of wind shadow from e.g. trees at the shoreline. More local measurements of the water surface, through wave heights or surface motion mapping, could give improved k-estimates over a surface, also taking into account wind fetch. At thermal infrared (IR) wavelengths water has very low reflectivity (depending on viewing angle) than can go below 1%, meaning that more than 99% is heat radiation giving a direct measurement of surface temperature variations. Using an IR camera at about 100 frames/s one could map surface temperature structures at a fraction of a mm depth even with waves present. In this presentation I will focus on IR imaging as a possible tool for estimating piston velocities. Results will be presented from IR field measurements, relating the motions of surface temperature structures to k calculated from other simultaneous measurements (flux chamber and ADV-Based Dissipation Rate), but also attempting to calculate k directly from the IR surface divergence. A relation between wave height and k will also be presented.

  13. Chemical imaging and solid state analysis at compact surfaces using UV imaging

    DEFF Research Database (Denmark)

    Wu, Jian X.; Rehder, Sönke; van den Berg, Frans

    2014-01-01

    and excipients in a non-invasive way, as well as mapping the glibenclamide solid state form. An exploratory data analysis supported the critical evaluation of the mapping results and the selection of model parameters for the chemical mapping. The present study demonstrated that the multi-wavelength UV imaging......Fast non-destructive multi-wavelength UV imaging together with multivariate image analysis was utilized to visualize distribution of chemical components and their solid state form at compact surfaces. Amorphous and crystalline solid forms of the antidiabetic compound glibenclamide...

  14. Tomographic image via background subtraction using an x-ray projection image and a priori computed tomography

    International Nuclear Information System (INIS)

    Zhang Jin; Yi Byongyong; Lasio, Giovanni; Suntharalingam, Mohan; Yu, Cedric

    2009-01-01

    Kilovoltage x-ray projection images (kV images for brevity) are increasingly available in image guided radiotherapy (IGRT) for patient positioning. These images are two-dimensional (2D) projections of a three-dimensional (3D) object along the x-ray beam direction. Projecting a 3D object onto a plane may lead to ambiguities in the identification of anatomical structures and to poor contrast in kV images. Therefore, the use of kV images in IGRT is mainly limited to bony landmark alignments. This work proposes a novel subtraction technique that isolates a slice of interest (SOI) from a kV image with the assistance of a priori information from a previous CT scan. The method separates structural information within a preselected SOI by suppressing contributions to the unprocessed projection from out-of-SOI-plane structures. Up to a five-fold increase in the contrast-to-noise ratios (CNRs) was observed in selected regions of the isolated SOI, when compared to the original unprocessed kV image. The tomographic image via background subtraction (TIBS) technique aims to provide a quick snapshot of the slice of interest with greatly enhanced image contrast over conventional kV x-ray projections for fast and accurate image guidance of radiation therapy. With further refinements, TIBS could, in principle, provide real-time tumor localization using gantry-mounted x-ray imaging systems without the need for implanted markers.

  15. Robustness of an artificially tailored fisheye imaging system with a curvilinear image surface

    Science.gov (United States)

    Lee, Gil Ju; Nam, Won Il; Song, Young Min

    2017-11-01

    Curved image sensors inspired by animal and insect eyes have provided a new development direction in next-generation digital cameras. It is known that natural fish eyes afford an extremely wide field of view (FOV) imaging due to the geometrical properties of the spherical lens and hemispherical retina. However, its inherent drawbacks, such as the low off-axis illumination and the fabrication difficulty of a 'dome-like' hemispherical imager, limit the development of bio-inspired wide FOV cameras. Here, a new type of fisheye imaging system is introduced that has simple lens configurations with a curvilinear image surface, while maintaining high off-axis illumination and a wide FOV. Moreover, through comparisons with commercial conventional fisheye designs, it is determined that the volume and required number of optical elements of the proposed design is practical while capturing the fundamental optical performances. Detailed design guidelines for tailoring the proposed optic system are also discussed.

  16. Tomography of images with poisson miose: pre-processing of projections

    International Nuclear Information System (INIS)

    Furuie, S.S.

    1989-01-01

    This work present an alternative approach in order to reconstruct images with low signal to noise ratio. Basically it consist of smoothing projections taking into account that the noise is Poisson. These filtered projections are used to reconstruct the original image, applying direct Fourier method. This approach is compared with convolution back projection and EM (Expectation-Maximization). (author) [pt

  17. Imaging near-surface heterogeneities by natural migration of backscattered surface waves: Field data test

    KAUST Repository

    Liu, Zhaolun; AlTheyab, Abdullah; Hanafy, Sherif M.; Schuster, Gerard T.

    2017-01-01

    We have developed a methodology for detecting the presence of near-surface heterogeneities by naturally migrating backscattered surface waves in controlled-source data. The near-surface heterogeneities must be located within a depth of approximately one-third the dominant wavelength λ of the strong surface-wave arrivals. This natural migration method does not require knowledge of the near-surface phase-velocity distribution because it uses the recorded data to approximate the Green’s functions for migration. Prior to migration, the backscattered data are separated from the original records, and the band-passed filtered data are migrated to give an estimate of the migration image at a depth of approximately one-third λ. Each band-passed data set gives a migration image at a different depth. Results with synthetic data and field data recorded over known faults validate the effectiveness of this method. Migrating the surface waves in recorded 2D and 3D data sets accurately reveals the locations of known faults. The limitation of this method is that it requires a dense array of receivers with a geophone interval less than approximately one-half λ.

  18. Imaging near-surface heterogeneities by natural migration of backscattered surface waves: Field data test

    KAUST Repository

    Liu, Zhaolun

    2017-03-06

    We have developed a methodology for detecting the presence of near-surface heterogeneities by naturally migrating backscattered surface waves in controlled-source data. The near-surface heterogeneities must be located within a depth of approximately one-third the dominant wavelength λ of the strong surface-wave arrivals. This natural migration method does not require knowledge of the near-surface phase-velocity distribution because it uses the recorded data to approximate the Green’s functions for migration. Prior to migration, the backscattered data are separated from the original records, and the band-passed filtered data are migrated to give an estimate of the migration image at a depth of approximately one-third λ. Each band-passed data set gives a migration image at a different depth. Results with synthetic data and field data recorded over known faults validate the effectiveness of this method. Migrating the surface waves in recorded 2D and 3D data sets accurately reveals the locations of known faults. The limitation of this method is that it requires a dense array of receivers with a geophone interval less than approximately one-half λ.

  19. Skin surface and sub-surface strain and deformation imaging using optical coherence tomography and digital image correlation

    Science.gov (United States)

    Hu, X.; Maiti, R.; Liu, X.; Gerhardt, L. C.; Lee, Z. S.; Byers, R.; Franklin, S. E.; Lewis, R.; Matcher, S. J.; Carré, M. J.

    2016-03-01

    Bio-mechanical properties of the human skin deformed by external forces at difference skin/material interfaces attract much attention in medical research. For instance, such properties are important design factors when one designs a healthcare device, i.e., the device might be applied directly at skin/device interfaces. In this paper, we investigated the bio-mechanical properties, i.e., surface strain, morphological changes of the skin layers, etc., of the human finger-pad and forearm skin as a function of applied pressure by utilizing two non-invasive techniques, i.e., optical coherence tomography (OCT) and digital image correlation (DIC). Skin deformation results of the human finger-pad and forearm skin were obtained while pressed against a transparent optical glass plate under the action of 0.5-24 N force and stretching naturally from 90° flexion to 180° full extension respectively. The obtained OCT images showed the deformation results beneath the skin surface, however, DIC images gave overall information of strain at the surface.

  20. National Land Imaging Requirements (NLIR) Pilot Project summary report: summary of moderate resolution imaging user requirements

    Science.gov (United States)

    Vadnais, Carolyn; Stensaas, Gregory

    2014-01-01

    Under the National Land Imaging Requirements (NLIR) Project, the U.S. Geological Survey (USGS) is developing a functional capability to obtain, characterize, manage, maintain and prioritize all Earth observing (EO) land remote sensing user requirements. The goal is a better understanding of community needs that can be supported with land remote sensing resources, and a means to match needs with appropriate solutions in an effective and efficient way. The NLIR Project is composed of two components. The first component is focused on the development of the Earth Observation Requirements Evaluation System (EORES) to capture, store and analyze user requirements, whereas, the second component is the mechanism and processes to elicit and document the user requirements that will populate the EORES. To develop the second component, the requirements elicitation methodology was exercised and refined through a pilot project conducted from June to September 2013. The pilot project focused specifically on applications and user requirements for moderate resolution imagery (5–120 meter resolution) as the test case for requirements development. The purpose of this summary report is to provide a high-level overview of the requirements elicitation process that was exercised through the pilot project and an early analysis of the moderate resolution imaging user requirements acquired to date to support ongoing USGS sustainable land imaging study needs. The pilot project engaged a limited set of Federal Government users from the operational and research communities and therefore the information captured represents only a subset of all land imaging user requirements. However, based on a comparison of results, trends, and analysis, the pilot captured a strong baseline of typical applications areas and user needs for moderate resolution imagery. Because these results are preliminary and represent only a sample of users and application areas, the information from this report should only

  1. 3D modeling to characterize lamina cribrosa surface and pore geometries using in vivo images from normal and glaucomatous eyes

    Science.gov (United States)

    Sredar, Nripun; Ivers, Kevin M.; Queener, Hope M.; Zouridakis, George; Porter, Jason

    2013-01-01

    En face adaptive optics scanning laser ophthalmoscope (AOSLO) images of the anterior lamina cribrosa surface (ALCS) represent a 2D projected view of a 3D laminar surface. Using spectral domain optical coherence tomography images acquired in living monkey eyes, a thin plate spline was used to model the ALCS in 3D. The 2D AOSLO images were registered and projected onto the 3D surface that was then tessellated into a triangular mesh to characterize differences in pore geometry between 2D and 3D images. Following 3D transformation of the anterior laminar surface in 11 normal eyes, mean pore area increased by 5.1 ± 2.0% with a minimal change in pore elongation (mean change = 0.0 ± 0.2%). These small changes were due to the relatively flat laminar surfaces inherent in normal eyes (mean radius of curvature = 3.0 ± 0.5 mm). The mean increase in pore area was larger following 3D transformation in 4 glaucomatous eyes (16.2 ± 6.0%) due to their more steeply curved laminar surfaces (mean radius of curvature = 1.3 ± 0.1 mm), while the change in pore elongation was comparable to that in normal eyes (−0.2 ± 2.0%). This 3D transformation and tessellation method can be used to better characterize and track 3D changes in laminar pore and surface geometries in glaucoma. PMID:23847739

  2. 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)

  3. A New Sensor for Surface Process Quantification in the Geosciences - Image-Assisted Tacheometers

    Science.gov (United States)

    Vicovac, Tanja; Reiterer, Alexander; Rieke-Zapp, Dirk

    2010-05-01

    The quantification of earth surface processes in the geosciences requires precise measurement tools. Typical applications for precise measurement systems involve deformation monitoring for geo-risk management, detection of erosion rates, etc. Often employed for such applications are laser scanners, photogrammetric sensors and image-assisted tacheometers. Image-assisted tacheometers offer the user (metrology expert) an image capturing system (CCD/CMOS camera) in addition to 3D point measurements. The images of the telescope's visual field are projected onto the camera's chip. The camera is capable of capturing panoramic image mosaics through camera rotation if the axes of the measurement system are driven by computer controlled motors. With appropriate calibration, these images are accurately geo-referenced and oriented since the horizontal and vertical angles of rotation are continuously measured and fed into the computer. The oriented images can then directly be used for direction measurements with no need for control points in object space or further photogrammetric orientation processes. In such a system, viewing angles must be addressed to chip pixels inside the optical field of view. Hence dedicated calibration methods have to be applied, an autofocus unit has to be added to the optical path, and special digital image processing procedures have to be used to detect the points of interest on the objects to be measured. We present such a new optical measurement system for measuring and describing 3D surfaces for geosciences. Besides the technique and methods some practical examples will be shown. The system was developed at the Vienna University of Technology (Institute of Geodesy and Geophysics) - two interdisciplinary research project, i-MeaS and SedyMONT, have been launched with the purpose of measuring and interpreting 3D surfaces and surface processes. For the in situ measurement of bed rock erosion the level of surveying accuracy required for recurring sub

  4. Image statistics and the perception of surface gloss and lightness.

    Science.gov (United States)

    Kim, Juno; Anderson, Barton L

    2010-07-01

    Despite previous data demonstrating the critical importance of 3D surface geometry in the perception of gloss and lightness, I. Motoyoshi, S. Nishida, L. Sharan, and E. H. Adelson (2007) recently proposed that a simple image statistic--histogram or sub-band skew--is computed by the visual system to infer the gloss and albedo of surfaces. One key source of evidence used to support this claim was an experiment in which adaptation to skewed image statistics resulted in opponent aftereffects in observers' judgments of gloss and lightness. We report a series of adaptation experiments that were designed to assess the cause of these aftereffects. We replicated their original aftereffects in gloss but found no consistent aftereffect in lightness. We report that adaptation to zero-skew adaptors produced similar aftereffects as positively skewed adaptors, and that negatively skewed adaptors induced no reliable aftereffects. We further find that the adaptation effect observed with positively skewed adaptors is not robust to changes in mean luminance that diminish the intensity of the luminance extrema. Finally, we show that adaptation to positive skew reduces (rather than increases) the apparent lightness of light pigmentation on non-uniform albedo surfaces. These results challenge the view that the adaptation results reported by Motoyoshi et al. (2007) provide evidence that skew is explicitly computed by the visual system.

  5. Multifractural analysis of AFM images of Nb thin film surfaces

    International Nuclear Information System (INIS)

    Altajskij, M.V; Chernenko, L.P.; Balebanov, V.M.; Erokhin, N.S.; Moiseev, S.S.

    2000-01-01

    The multifractal analysis of the atomic Force Microscope (AFM) images of the Niobium (Nb) thin film surfaces has been performed. These Nb films are being used for the measurements of the London penetration depth of stationary magnetic field by polarized neutron reflectometry. The analysis shows the behavior of Renyi dimensions of images (in the range of available scales 6-2000 nm), like the known multifractal p-model, with typical Hausdorff dimension of prevalent color in the range of 1.6-1.9. This indicates the fractal nature of film landscape on those scales. The perspective of new mechanism of order parameter suppression on superconductor-vacuum boundary, manifested in anomalous magnetic field penetration in discussed

  6. Photometric imaging in particle size measurement and surface visualization.

    Science.gov (United States)

    Sandler, Niklas

    2011-09-30

    The aim of this paper is to give an insight into photometric particle sizing approaches, which differ from the typical particle size measurement of dispersed particles. These approaches can often be advantageous especially for samples that are moist or cohesive, when dispersion of particles is difficult or sometimes impossible. The main focus of this paper is in the use of photometric stereo imaging. The technique allows the reconstruction of three-dimensional images of objects using multiple light sources in illumination. The use of photometric techniques is demonstrated in at-line measurement of granules and on-line measurement during granulation and dry milling. Also, surface visualization and roughness measurements are briefly discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Surface flaw evaluation by vectorized eddy current testing image

    International Nuclear Information System (INIS)

    Endo, Hisashi; Takagi, Toshiyuki

    2006-01-01

    A method of eddy current testing (ECT) data mapping for surface breaking evaluation is studied. The multicoil ECT probe utilized in this paper consists of Transmit-Receive (TR) type sensors as array elements to obtain the information on crack directions. Switching two directional scans, U- and T- modes, gives two-dimensional vector mapping as ECT images. The ECT signals of the TR type sensor also give the information on crack directions from their variation displayed on the complex number plane. Extracting a complex number component of the signals makes it possible to visualize directions of numerically simulated proximate EDM slits. (author)

  8. Computer screen photo-excited surface plasmon resonance imaging.

    Science.gov (United States)

    Filippini, Daniel; Winquist, Fredrik; Lundström, Ingemar

    2008-09-12

    Angle and spectra resolved surface plasmon resonance (SPR) images of gold and silver thin films with protein deposits is demonstrated using a regular computer screen as light source and a web camera as detector. The screen provides multiple-angle illumination, p-polarized light and controlled spectral radiances to excite surface plasmons in a Kretchmann configuration. A model of the SPR reflectances incorporating the particularities of the source and detector explain the observed signals and the generation of distinctive SPR landscapes is demonstrated. The sensitivity and resolution of the method, determined in air and solution, are 0.145 nm pixel(-1), 0.523 nm, 5.13x10(-3) RIU degree(-1) and 6.014x10(-4) RIU, respectively, encouraging results at this proof of concept stage and considering the ubiquity of the instrumentation.

  9. A segmentation algorithm based on image projection for complex text layout

    Science.gov (United States)

    Zhu, Wangsheng; Chen, Qin; Wei, Chuanyi; Li, Ziyang

    2017-10-01

    Segmentation algorithm is an important part of layout analysis, considering the efficiency advantage of the top-down approach and the particularity of the object, a breakdown of projection layout segmentation algorithm. Firstly, the algorithm will algorithm first partitions the text image, and divided into several columns, then for each column scanning projection, the text image is divided into several sub regions through multiple projection. The experimental results show that, this method inherits the projection itself and rapid calculation speed, but also can avoid the effect of arc image information page segmentation, and also can accurate segmentation of the text image layout is complex.

  10. Quantifying Uncertainty in Near Surface Electromagnetic Imaging Using Bayesian Methods

    Science.gov (United States)

    Blatter, D. B.; Ray, A.; Key, K.

    2017-12-01

    Geoscientists commonly use electromagnetic methods to image the Earth's near surface. Field measurements of EM fields are made (often with the aid an artificial EM source) and then used to infer near surface electrical conductivity via a process known as inversion. In geophysics, the standard inversion tool kit is robust and can provide an estimate of the Earth's near surface conductivity that is both geologically reasonable and compatible with the measured field data. However, standard inverse methods struggle to provide a sense of the uncertainty in the estimate they provide. This is because the task of finding an Earth model that explains the data to within measurement error is non-unique - that is, there are many, many such models; but the standard methods provide only one "answer." An alternative method, known as Bayesian inversion, seeks to explore the full range of Earth model parameters that can adequately explain the measured data, rather than attempting to find a single, "ideal" model. Bayesian inverse methods can therefore provide a quantitative assessment of the uncertainty inherent in trying to infer near surface conductivity from noisy, measured field data. This study applies a Bayesian inverse method (called trans-dimensional Markov chain Monte Carlo) to transient airborne EM data previously collected over Taylor Valley - one of the McMurdo Dry Valleys in Antarctica. Our results confirm the reasonableness of previous estimates (made using standard methods) of near surface conductivity beneath Taylor Valley. In addition, we demonstrate quantitatively the uncertainty associated with those estimates. We demonstrate that Bayesian inverse methods can provide quantitative uncertainty to estimates of near surface conductivity.

  11. Fluorescence spectral imaging as a tool for locating uranium deposited on surfaces - 16089

    International Nuclear Information System (INIS)

    Monts, David L.; Wang, Guangjun; Su, Yi; Jang, Ping-Rey; Waggoner, Charles A.

    2009-01-01

    In the environment, metallic uranium readily oxidizes to form uranium compounds that contain the uranyl (UO 2 +2 ) moiety. For more than a hundred and fifty years, it has been known that when illuminated with ultraviolet (UV) light, uranyl compounds exhibit characteristic fluorescence in the visible region (450-650 nm). We report our efforts to develop a transportable, quantitative Fluorescence Spectral Imaging (FSI) system as a tool for locating and quantifying uranyl compounds dispersed in soils and on other surfaces. A project is underway to develop a set of sensors to locate expended depleted uranium (DU) rounds and to process soil and debris to recover the material from domestic firing ranges. The FSI system can also be utilized to monitor excavation of DU munitions and separation of uranyl compounds from soils. FSI images are acquired by illuminating a surface with a UV light and using a narrow band pass filter on a camera, recording an image of the resulting fluorescence. The FSI image provides both spatial and spectral information. The FSI system is described and its performance characterized using field samples. (authors)

  12. Reconstruction of a cone-beam CT image via forward iterative projection matching

    International Nuclear Information System (INIS)

    Brock, R. Scott; Docef, Alen; Murphy, Martin J.

    2010-01-01

    Purpose: To demonstrate the feasibility of reconstructing a cone-beam CT (CBCT) image by deformably altering a prior fan-beam CT (FBCT) image such that it matches the anatomy portrayed in the CBCT projection data set. Methods: A prior FBCT image of the patient is assumed to be available as a source image. A CBCT projection data set is obtained and used as a target image set. A parametrized deformation model is applied to the source FBCT image, digitally reconstructed radiographs (DRRs) that emulate the CBCT projection image geometry are calculated and compared to the target CBCT projection data, and the deformation model parameters are adjusted iteratively until the DRRs optimally match the CBCT projection data set. The resulting deformed FBCT image is hypothesized to be an accurate representation of the patient's anatomy imaged by the CBCT system. The process is demonstrated via numerical simulation. A known deformation is applied to a prior FBCT image and used to create a synthetic set of CBCT target projections. The iterative projection matching process is then applied to reconstruct the deformation represented in the synthetic target projections; the reconstructed deformation is then compared to the known deformation. The sensitivity of the process to the number of projections and the DRR/CBCT projection mismatch is explored by systematically adding noise to and perturbing the contrast of the target projections relative to the iterated source DRRs and by reducing the number of projections. Results: When there is no noise or contrast mismatch in the CBCT projection images, a set of 64 projections allows the known deformed CT image to be reconstructed to within a nRMS error of 1% and the known deformation to within a nRMS error of 7%. A CT image nRMS error of less than 4% is maintained at noise levels up to 3% of the mean projection intensity, at which the deformation error is 13%. At 1% noise level, the number of projections can be reduced to 8 while maintaining

  13. 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)

  14. BUILDING DETECTION USING AERIAL IMAGES AND DIGITAL SURFACE MODELS

    Directory of Open Access Journals (Sweden)

    J. Mu

    2017-05-01

    Full Text Available In this paper a method for building detection in aerial images based on variational inference of logistic regression is proposed. It consists of three steps. In order to characterize the appearances of buildings in aerial images, an effective bag-of-Words (BoW method is applied for feature extraction in the first step. In the second step, a classifier of logistic regression is learned using these local features. The logistic regression can be trained using different methods. In this paper we adopt a fully Bayesian treatment for learning the classifier, which has a number of obvious advantages over other learning methods. Due to the presence of hyper prior in the probabilistic model of logistic regression, approximate inference methods have to be applied for prediction. In order to speed up the inference, a variational inference method based on mean field instead of stochastic approximation such as Markov Chain Monte Carlo is applied. After the prediction, a probabilistic map is obtained. In the third step, a fully connected conditional random field model is formulated and the probabilistic map is used as the data term in the model. A mean field inference is utilized in order to obtain a binary building mask. A benchmark data set consisting of aerial images and digital surfaced model (DSM released by ISPRS for 2D semantic labeling is used for performance evaluation. The results demonstrate the effectiveness of the proposed method.

  15. MULTIPLE IMAGING TECHNIQUES DEMONSTRATE THE MANIPULATION OF SURFACES TO REDUCE BACTERIAL CONTAMINATION

    Science.gov (United States)

    Surface imaging techniques were combined to determine appropriate manipulation of technologically important surfaces for commercial applications. Stainless steel surfaces were engineered to reduce bacterial contamination, biofilm formation, and corrosion during product processing...

  16. 78 FR 53712 - Surface Transportation Project Delivery Program Application Requirements

    Science.gov (United States)

    2013-08-30

    ... application, and discussion of classes of multimodal projects that may be best handled on a case-by-case basis... submissions; a paragraph discussing the joint application process; and a paragraph authorizing the Agencies to... early enough to allow for a joint application of the Secretary's responsibilities before the...

  17. Atmospheres – Through Projections on a Living Surface

    DEFF Research Database (Denmark)

    Steijn, Arthur

    2013-01-01

    of space, liveness and atmosphere. With the development of this model I wish to contribute to the on-going development of the use of video projections and motion graphics as important visual, spatial and narrative elements within the field of spatial experience design, e.g. in performance, exhibition...

  18. Matching Images to Models: Camera Calibration for 3-D Surface Reconstruction

    Science.gov (United States)

    Morris, Robin D.; Smelyanskiy, Vadim N.; Cheeseman. Peter C.; Norvig, Peter (Technical Monitor)

    2001-01-01

    In a previous paper we described a system which recursively recovers a super-resolved three dimensional surface model from a set of images of the surface. In that paper we assumed that the camera calibration for each image was known. In this paper we solve two problems. Firstly, if an estimate of the surface is already known, the problem is to calibrate a new image relative to the existing surface model. Secondly, if no surface estimate is available, the relative camera calibration between the images in the set must be estimated. This will allow an initial surface model to be estimated. Results of both types of estimation are given.

  19. Direct Imaging of Stellar Surfaces: Results from the Stellar Imager (SI) Vision Mission Study

    Science.gov (United States)

    Carpenter, Kenneth; Schrijver, Carolus; Karovska, Margarita

    2006-01-01

    The Stellar Imager (SI) is a UV-Optical, Space-Based Interferometer designed to enable 0.1 milli-arcsecond (mas) spectral imaging of stellar surfaces and stellar interiors (via asteroseismology) and of the Universe in general. SI is identified as a "Flagship and Landmark Discovery Mission'' in the 2005 Sun Solar System Connection (SSSC) Roadmap and as a candidate for a "Pathways to Life Observatory'' in the Exploration of the Universe Division (EUD) Roadmap (May, 2005). The ultra-sharp images of the Stellar Imager will revolutionize our view of many dynamic astrophysical processes: The 0.1 mas resolution of this deep-space telescope will transform point sources into extended sources, and snapshots into evolving views. SI's science focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. SI's prime goal is to enable long-term forecasting of solar activity and the space weather that it drives in support of the Living With a Star program in the Exploration Era. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in the Universe. In this paper we will discuss the results of the SI Vision Mission Study, elaborating on the science goals of the SI Mission and a mission architecture that could meet those goals.

  20. Digital fringe projection for hand surface coordinate variation analysis caused by osteoarthritis

    Science.gov (United States)

    Nor Haimi, Wan Mokhdzani Wan; Hau Tan, Cheek; Retnasamy, Vithyacharan; Vairavan, Rajendaran; Sauli, Zaliman; Roshidah Yusof, Nor; Hambali, Nor Azura Malini Ahmad; Aziz, Muhammad Hafiz Ab; Bakhit, Ahmad Syahir Ahmad

    2017-11-01

    Hand osteoarthritis is one of the most common forms of arthritis which impact millions of people worldwide. The disabling problem occurs when the protective cartilage on the boundaries of bones wear off over time. Currently, in order to identify hand osteoarthritis, special instruments namely X-ray scanning and MRI are used for the detection but it also has its limitations such as radiation exposure and can be quite costly. In this work, an optical metrology system based on digital fringe projection which comprises of an LCD projector, CCD camera and a personal computer has been developed to anticipate abnormal growth or deformation on the joints of the hand which are common symptoms of osteoarthritis. The main concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted by 3 phase shifts based on the 3 steps 2 shifts method. Phase wrapping technique and analysis were applied in order to detect the deformation of live subjects. The result has demonstrated a successful method of hand deformation detection based on the pixel tracking differences of a normal and deformed state.

  1. UMTRA project technical assistance contractor quality assurance implementation plan for surface and ground water

    International Nuclear Information System (INIS)

    1994-09-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project Technical Assistance Contractor (TAC) Quality Assurance Implementation Plan (QAIP) outlines the primary requirements for integrating quality functions for TAC technical activities applied to the surface and ground water phases of the UMTRA Project. The QAIP is subordinate to the latest issue of the UMTRA Project TAC Quality Assurance Program Plan (QAPP). The QAIP addresses technical aspects of the TAC UMTRA Project surface and ground water programs. The QAIP is authorized and approved by the TAC Project Manager and QA manager. The QA program is designed to use monitoring, audit, and surveillance functions as management tools to ensure that all Project organization activities are carried out in a manner that will protect public health and safety, promote the success of the UMTRA Project and meet or exceed contract requirements

  2. Indonesia sea surface temperature from TRMM Microwave Imaging (TMI) sensor

    Science.gov (United States)

    Marini, Y.; Setiawan, K. T.

    2018-05-01

    We analysis the Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI) data to monitor the sea surface temperature (SST) of Indonesia waters for a decade of 2005-2014. The TMI SST data shows the seasonal and interannual SST in Indonesian waters. In general, the SST average was highest in March-May period with SST average was 29.4°C, and the lowest was in June – August period with the SST average was 28.5°C. The monthly SST average fluctuation of Indonesian waters for 10 years tends to increase. The lowest SST average of Indonesia occurred in August 2006 with the SST average was 27.6° C, while the maximum occurred in May 2014 with the monthly SST average temperature was 29.9 ° C.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-07-01

    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{sup -2} seems possible in the near future. (author)

  4. 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)

  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. Projection of curves on B-spline surfaces using quadratic reparameterization

    KAUST Repository

    Yang, Yijun

    2010-09-01

    Curves on surfaces play an important role in computer aided geometric design. In this paper, we present a hyperbola approximation method based on the quadratic reparameterization of Bézier surfaces, which generates reasonable low degree curves lying completely on the surfaces by using iso-parameter curves of the reparameterized surfaces. The Hausdorff distance between the projected curve and the original curve is controlled under the user-specified distance tolerance. The projected curve is T-G 1 continuous, where T is the user-specified angle tolerance. Examples are given to show the performance of our algorithm. © 2010 Elsevier Inc. All rights reserved.

  7. Development of Fluorescence Spectral Imaging for Location of Uranium Deposited on Surfaces

    International Nuclear Information System (INIS)

    Monts, D.L.; Wang, G.; Su, Y.; Jang, P.R.; Waggoner, Ch.A.

    2009-01-01

    Since the 1980's, depleted uranium (DU) has been the primary material used by the US military in armor-piercing rounds. Domestic firing ranges that have been used for DU munitions training purposes are located around the country and have varying extents of contamination by other types of projectiles. A project is underway to develop a set of sensors to locate expended DU rounds and to process soil and debris to recover the material. In the environment, metallic DU readily oxidizes to form uranium compounds that contain the uranyl (UO 2 +2 ) moiety. For more than a hundred and fifty years, it has been known that when illuminated with ultraviolet (UV) light, uranyl compounds exhibit characteristic fluorescence in the visible region (450 - 650 nm). We report our efforts to develop a transportable, quantitative Fluorescence Spectral Imaging (FSI) system to locate and quantify uranyl compounds dispersed in soils and on other surfaces on domestic firing ranges; this system can also be utilized to monitor excavation of DU munitions and separation of uranyl compounds from soils. FSI images are acquired by illuminating a surface with a UV light and using a narrow band pass filter on a camera, recording an image of the resulting fluorescence. FSI images provide both spatial and spectral information. The FSI system is described and its performance characterized in the field and also by using field samples. The development and characterization of an improved transportable FSI system is presented. The applicability of this system for detection of uranium compounds deposited on surfaces for Decontaminating and Decommissioning (D and D) activities is discussed. We have successfully demonstrated in situ a first-generation, transportable Fluorescence Spectral Imaging (FSI) system for locating uranyl compounds dispersed in soils and on other surfaces of a domestic firing range. FSI images provide both spatial and spectral information. FSI images are acquired by illuminating a

  8. 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)

  9. Surface-Enhanced Raman Scattering Nanoparticles as Optical Labels for Imaging Cell Surface Proteins

    Science.gov (United States)

    MacLaughlin, Christina M.

    Assaying the expression of cell surface proteins has widespread application for characterizing cell type, developmental stage, and monitoring disease transformation. Immunophenotyping is conducted by treating cells with labelled targeting moieties that have high affinity for relevant surface protein(s). The sensitivity and specificity of immunophenotyping is defined by the choice of contrast agent and therefore, the number of resolvable signals that can be used to simultaneously label cells. Narrow band width surface-enhanced Raman scattering (SERS) nanoparticles are proposed as optical labels for multiplexed immunophenotying. Two types of surface coatings were investigated to passivate the gold nanoparticles, incorporate SERS functionality, and to facilitate attachment of targeting antibodies. Thiolated poly(ethylene glycol) forms dative bonds with the gold surface and is compatible with multiple physisorbed Raman-active reporter molecules. Ternary lipid bilayers are used to encapsulate the gold nanoparticles particles, and incorporate three different classes of Raman reporters. TEM, UV-Visible absorbance spectroscopy, DLS, and electrophoretic light scattering were used characterize the particle coating. Colourimetric protein assay, and secondary antibody labelling were used to quantify the antibody conjugation. Three different in vitromodels were used to investigate the binding efficacy and specificity of SERS labels for their biomarker targets. Primary human CLL cells, LY10 B lymphoma, and A549 adenocarcinoma lines were targeted. Dark field imaging was used to visualize the colocalization of SERS labels with cells, and evidence of receptor clustering was obtained based on colour shifts of the particles' Rayleigh scattering. Widefield, and spatially-resolved Raman spectra were used to detect labels singly, and in combination from labelled cells. Fluorescence flow cytometry was used to test the particles' binding specificity, and SERS from labelled cells was also

  10. Precision 3d Surface Reconstruction from Lro Nac Images Using Semi-Global Matching with Coupled Epipolar Rectification

    Science.gov (United States)

    Hu, H.; Wu, B.

    2017-07-01

    The Narrow-Angle Camera (NAC) on board the Lunar Reconnaissance Orbiter (LRO) comprises of a pair of closely attached high-resolution push-broom sensors, in order to improve the swath coverage. However, the two image sensors do not share the same lenses and cannot be modelled geometrically using a single physical model. Thus, previous works on dense matching of stereo pairs of NAC images would generally create two to four stereo models, each with an irregular and overlapping region of varying size. Semi-Global Matching (SGM) is a well-known dense matching method and has been widely used for image-based 3D surface reconstruction. SGM is a global matching algorithm relying on global inference in a larger context rather than individual pixels to establish stable correspondences. The stereo configuration of LRO NAC images causes severe problem for image matching methods such as SGM, which emphasizes global matching strategy. Aiming at using SGM for image matching of LRO NAC stereo pairs for precision 3D surface reconstruction, this paper presents a coupled epipolar rectification methods for LRO NAC stereo images, which merges the image pair in the disparity space and in this way, only one stereo model will be estimated. For a stereo pair (four) of NAC images, the method starts with the boresight calibration by finding correspondence in the small overlapping stripe between each pair of NAC images and bundle adjustment of the stereo pair, in order to clean the vertical disparities. Then, the dominate direction of the images are estimated by project the center of the coverage area to the reference image and back-projected to the bounding box plane determined by the image orientation parameters iteratively. The dominate direction will determine an affine model, by which the pair of NAC images are warped onto the object space with a given ground resolution and in the meantime, a mask is produced indicating the owner of each pixel. SGM is then used to generate a disparity

  11. PRECISION 3D SURFACE RECONSTRUCTION FROM LRO NAC IMAGES USING SEMI-GLOBAL MATCHING WITH COUPLED EPIPOLAR RECTIFICATION

    Directory of Open Access Journals (Sweden)

    H. Hu

    2017-07-01

    Full Text Available The Narrow-Angle Camera (NAC on board the Lunar Reconnaissance Orbiter (LRO comprises of a pair of closely attached high-resolution push-broom sensors, in order to improve the swath coverage. However, the two image sensors do not share the same lenses and cannot be modelled geometrically using a single physical model. Thus, previous works on dense matching of stereo pairs of NAC images would generally create two to four stereo models, each with an irregular and overlapping region of varying size. Semi-Global Matching (SGM is a well-known dense matching method and has been widely used for image-based 3D surface reconstruction. SGM is a global matching algorithm relying on global inference in a larger context rather than individual pixels to establish stable correspondences. The stereo configuration of LRO NAC images causes severe problem for image matching methods such as SGM, which emphasizes global matching strategy. Aiming at using SGM for image matching of LRO NAC stereo pairs for precision 3D surface reconstruction, this paper presents a coupled epipolar rectification methods for LRO NAC stereo images, which merges the image pair in the disparity space and in this way, only one stereo model will be estimated. For a stereo pair (four of NAC images, the method starts with the boresight calibration by finding correspondence in the small overlapping stripe between each pair of NAC images and bundle adjustment of the stereo pair, in order to clean the vertical disparities. Then, the dominate direction of the images are estimated by project the center of the coverage area to the reference image and back-projected to the bounding box plane determined by the image orientation parameters iteratively. The dominate direction will determine an affine model, by which the pair of NAC images are warped onto the object space with a given ground resolution and in the meantime, a mask is produced indicating the owner of each pixel. SGM is then used to

  12. 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 ......- tor transform outperform the linear methods as well as kernel principal components in producing interesting projections of the data.......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...

  13. Multi-sheet surface rebinning methods for reconstruction from asymmetrically truncated cone beam projections: I. Approximation and optimality

    International Nuclear Information System (INIS)

    Betcke, Marta M; Lionheart, William R B

    2013-01-01

    The mechanical motion of the gantry in conventional cone beam CT scanners restricts the speed of data acquisition in applications with near real time requirements. A possible resolution of this problem is to replace the moving source detector assembly with static parts that are electronically activated. An example of such a system is the Rapiscan Systems RTT80 real time tomography scanner, with a static ring of sources and axially offset static cylinder of detectors. A consequence of such a design is asymmetrical axial truncation of the cone beam projections resulting, in the sense of integral geometry, in severely incomplete data. In particular we collect data only in a fraction of the Tam–Danielsson window, hence the standard cone beam reconstruction techniques do not apply. In this work we propose a family of multi-sheet surface rebinning methods for reconstruction from such truncated projections. The proposed methods combine analytical and numerical ideas utilizing linearity of the ray transform to reconstruct data on multi-sheet surfaces, from which the volumetric image is obtained through deconvolution. In this first paper in the series, we discuss the rebinning to multi-sheet surfaces. In particular we concentrate on the underlying transforms on multi-sheet surfaces and their approximation with data collected by offset multi-source scanning geometries like the RTT. The optimal multi-sheet surface and the corresponding rebinning function are found as a solution of a variational problem. In the case of the quadratic objective, the variational problem for the optimal rebinning pair can be solved by a globally convergent iteration. Examples of optimal rebinning pairs are computed for different trajectories. We formulate the axial deconvolution problem for the recovery of the volumetric image from the reconstructions on multi-sheet surfaces. Efficient and stable solution of the deconvolution problem is the subject of the second paper in this series (Betcke and

  14. Accelerated Optical Projection Tomography Applied to In Vivo Imaging of Zebrafish.

    Directory of Open Access Journals (Sweden)

    Teresa Correia

    Full Text Available Optical projection tomography (OPT provides a non-invasive 3-D imaging modality that can be applied to longitudinal studies of live disease models, including in zebrafish. Current limitations include the requirement of a minimum number of angular projections for reconstruction of reasonable OPT images using filtered back projection (FBP, which is typically several hundred, leading to acquisition times of several minutes. It is highly desirable to decrease the number of required angular projections to decrease both the total acquisition time and the light dose to the sample. This is particularly important to enable longitudinal studies, which involve measurements of the same fish at different time points. In this work, we demonstrate that the use of an iterative algorithm to reconstruct sparsely sampled OPT data sets can provide useful 3-D images with 50 or fewer projections, thereby significantly decreasing the minimum acquisition time and light dose while maintaining image quality. A transgenic zebrafish embryo with fluorescent labelling of the vasculature was imaged to acquire densely sampled (800 projections and under-sampled data sets of transmitted and fluorescence projection images. The under-sampled OPT data sets were reconstructed using an iterative total variation-based image reconstruction algorithm and compared against FBP reconstructions of the densely sampled data sets. To illustrate the potential for quantitative analysis following rapid OPT data acquisition, a Hessian-based method was applied to automatically segment the reconstructed images to select the vasculature network. Results showed that 3-D images of the zebrafish embryo and its vasculature of sufficient visual quality for quantitative analysis can be reconstructed using the iterative algorithm from only 32 projections-achieving up to 28 times improvement in imaging speed and leading to total acquisition times of a few seconds.

  15. 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.

  16. Integrated surface management for pipeline construction: The Mid-America Pipeline Company Four Corners Project

    Science.gov (United States)

    Maria L. Sonett

    1999-01-01

    Integrated surface management techniques for pipeline construction through arid and semi-arid rangeland ecosystems are presented in a case history of a 412-mile pipeline construction project in New Mexico. Planning, implementation and monitoring for restoration of surface hydrology, soil stabilization, soil cover, and plant species succession are discussed. Planning...

  17. 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

  18. Three-dimensional surface reconstruction imaging for evaluation of congenital heart disease from ECG-triggered MR images

    International Nuclear Information System (INIS)

    Vannier, M.W.; Laschinger, J.; Knapp, R.H.; Gutierrez, F.R.; Gronnemeyer, S.A.

    1987-01-01

    Three-dimensional surface reconstruction images of the heart and great vessels were produced from contiguous sequences of electrocardiographically triggered MR images in 25 patients with congenital heart disease and in three healthy subjects. The imaging data were semiautomatically processed to separate the epicardial and endocardial surfaces and to define the outline of the enclosed blood volumes on a section by section basis. Images were obtained at 5-mm intervals in patients aged 3 months to 30 years with anomalies of the great vessels, tetralogy of Fallot, septal defects, pulmonary atresia, and other congenital heart malformations. The results were used to facilitate the surgical treatment of these patients and were compared with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. These surface reconstruction images were useful for communicating the results of diagnostic examinations to cardiac surgeons, for sizing and location of intracardiac defects, for imaging the pulmonary venous drainage, and for assessing regional and global function

  19. 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.

  20. 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)

  1. "Intelligent Ensemble" Projections of Precipitation and Surface Radiation in Support of Agricultural Climate Change Adaptation

    Science.gov (United States)

    Taylor, Patrick C.; Baker, Noel C.

    2015-01-01

    Earth's climate is changing and will continue to change into the foreseeable future. Expected changes in the climatological distribution of precipitation, surface temperature, and surface solar radiation will significantly impact agriculture. Adaptation strategies are, therefore, required to reduce the agricultural impacts of climate change. Climate change projections of precipitation, surface temperature, and surface solar radiation distributions are necessary input for adaption planning studies. These projections are conventionally constructed from an ensemble of climate model simulations (e.g., the Coupled Model Intercomparison Project 5 (CMIP5)) as an equal weighted average, one model one vote. Each climate model, however, represents the array of climate-relevant physical processes with varying degrees of fidelity influencing the projection of individual climate variables differently. Presented here is a new approach, termed the "Intelligent Ensemble, that constructs climate variable projections by weighting each model according to its ability to represent key physical processes, e.g., precipitation probability distribution. This approach provides added value over the equal weighted average method. Physical process metrics applied in the "Intelligent Ensemble" method are created using a combination of NASA and NOAA satellite and surface-based cloud, radiation, temperature, and precipitation data sets. The "Intelligent Ensemble" method is applied to the RCP4.5 and RCP8.5 anthropogenic climate forcing simulations within the CMIP5 archive to develop a set of climate change scenarios for precipitation, temperature, and surface solar radiation in each USDA Farm Resource Region for use in climate change adaptation studies.

  2. Method of surface error visualization using laser 3D projection technology

    Science.gov (United States)

    Guo, Lili; Li, Lijuan; Lin, Xuezhu

    2017-10-01

    In the process of manufacturing large components, such as aerospace, automobile and shipping industry, some important mold or stamped metal plate requires precise forming on the surface, which usually needs to be verified, if necessary, the surface needs to be corrected and reprocessed. In order to make the correction of the machined surface more convenient, this paper proposes a method based on Laser 3D projection system, this method uses the contour form of terrain contour, directly showing the deviation between the actually measured data and the theoretical mathematical model (CAD) on the measured surface. First, measure the machined surface to get the point cloud data and the formation of triangular mesh; secondly, through coordinate transformation, unify the point cloud data to the theoretical model and calculate the three-dimensional deviation, according to the sign (positive or negative) and size of the deviation, use the color deviation band to denote the deviation of three-dimensional; then, use three-dimensional contour lines to draw and represent every coordinates deviation band, creating the projection files; finally, import the projection files into the laser projector, and make the contour line projected to the processed file with 1:1 in the form of a laser beam, compare the Full-color 3D deviation map with the projection graph, then, locate and make quantitative correction to meet the processing precision requirements. It can display the trend of the machined surface deviation clearly.

  3. 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...

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

    KAUST Repository

    Desmal, Abdulla; Bagci, Hakan

    2017-01-01

    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

  5. Direct UV/Optical Imaging of Stellar Surfaces: The Stellar Imager (SI) Vision Mission

    Science.gov (United States)

    Carpenter, Kenneth G.; Lyon, Richard G.; Schrijver, Carolus; Karovska, Margarita; Mozurkewich, David

    2007-01-01

    The Stellar Imager (SI) is a UV/optical, space-based interferometer designed to enable 0.1 milli-arcsecond (mas) spectral imaging of stellar surfaces and, via asteroseismology, stellar interiors and of the Universe in general. SI's science focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. SI's prime goal is to enable long-term forecasting of solar activity and the space weather that it drives, in support of the Living with a Star program in the Exploration Era. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in thc Universe. SI is a "Flagship and Landmark Discovery Mission" in the 2005 Sun Solar System Connection (SSSC) Roadmap and a candidate for a "Pathways to Life Observatory" in the Exploration of the Universe Division (EUD) Roadmap. We discuss herein the science goals of the SI Mission, a mission architecture that could meet those goals, and the technologies needed to enable this mission. Additional information on SI can be found at: http://hires.gsfc.nasa.gov/si/.

  6. 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.)

  7. Digital projection radiography. Technical principles, image properties and potential applications

    International Nuclear Information System (INIS)

    Busch, H.P.

    1999-01-01

    The history of development of digital projection radiography as a diagnostic method is presented in a comprehensive survey. The various technical principles are explained in detail and illustrated by means of graphic figures and digital X-ray pictures. A comparative assessment of currently applied radiographic systems is given and the potential clinical applications of the method of digital projection radiography are discussed. (orig./CB) [de

  8. Visualization of brain surface structures by weighted summation technique using multislice MR images

    International Nuclear Information System (INIS)

    Machida, Yoshio; Hatanaka, Masahiko; Hagiwara, Masayuki; Sugimoto, Hiroshi; Yoshida, Tadatoki; Katada, Kazuhiro.

    1991-01-01

    Surface anatomy scanning (SAS) technique which visualizes brain surface structures has been developed since 1987. In this paper, we propose a modified method called 'multislice SAS', which also generates such surface structure images, and has several advantages compared with conventional SAS technique. The conventional SAS technique uses a very long echo time sequence (e.g. SE(3000, 250)) with a thick slice and a surface coil to enhance CSF on the brain surface. Our modified technique also uses a long echo time sequence. But, added multislice images, each appropriately weighted, are used in stead of a thick slice and a surface coil. Our basic studies have shown that this modified method has the following advantage: Several surface images with slightly different summation directions are obtained, and they are used for stereographic display and cine display. This is very useful for visualizing the spatial relationship of brain surface structures. By choosing appropriate weighting, we can obtain clinically legible surface images. This technique dose not require a surface coil. It means that flexibility of selecting imaging direction is high. We can make a lot of modifications, because the original multislice images of weighted summation are arbitrary. And we also clarify some limitation or disadvantage of this modified method. In conclusion, we think that this technique is one of the practical approaches for surface anatomy imaging. (author)

  9. Using Sentinel-1 and Landsat 8 satellite images to estimate surface soil moisture content.

    Science.gov (United States)

    Mexis, Philippos-Dimitrios; Alexakis, Dimitrios D.; Daliakopoulos, Ioannis N.; Tsanis, Ioannis K.

    2016-04-01

    Nowadays, the potential for more accurate assessment of Soil Moisture (SM) content exploiting Earth Observation (EO) technology, by exploring the use of synergistic approaches among a variety of EO instruments has emerged. This study is the first to investigate the potential of Synthetic Aperture Radar (SAR) (Sentinel-1) and optical (Landsat 8) images in combination with ground measurements to estimate volumetric SM content in support of water management and agricultural practices. SAR and optical data are downloaded and corrected in terms of atmospheric, geometric and radiometric corrections. SAR images are also corrected in terms of roughness and vegetation with the synergistic use of Oh and Topp models using a dataset consisting of backscattering coefficients and corresponding direct measurements of ground parameters (moisture, roughness). Following, various vegetation indices (NDVI, SAVI, MSAVI, EVI, etc.) are estimated to record diachronically the vegetation regime within the study area and as auxiliary data in the final modeling. Furthermore, thermal images from optical data are corrected and incorporated to the overall approach. The basic principle of Thermal InfraRed (TIR) method is that Land Surface Temperature (LST) is sensitive to surface SM content due to its impact on surface heating process (heat capacity and thermal conductivity) under bare soil or sparse vegetation cover conditions. Ground truth data are collected from a Time-domain reflectometer (TRD) gauge network established in western Crete, Greece, during 2015. Sophisticated algorithms based on Artificial Neural Networks (ANNs) and Multiple Linear Regression (MLR) approaches are used to explore the statistical relationship between backscattering measurements and SM content. Results highlight the potential of SAR and optical satellite images to contribute to effective SM content detection in support of water resources management and precision agriculture. Keywords: Sentinel-1, Landsat 8, Soil

  10. 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

  11. Z-Contrast STEM Imaging and EELS of CdSe Nanocrystals: Towards the Analysis of Individual Nanocrystal Surfaces

    International Nuclear Information System (INIS)

    Erwin, M.; Kadavanich, A.V.; Kippeny, T.; Pennycook, S.J.; Rosenthal, S.J.

    1999-01-01

    We have applied Atomic Number Contract Scanning Transmission Electron Microscopy (Z-Contrast STEM) and STEM/EELS (Electron Energy Loss Spectroscopy) towards the study of colloidal CdSe semiconductor nanocrystals embedded in MEH-PPV polymer films. Unlike the case of conventional phase-contrast High Resolution TEM, Z-Contrast images are direct projections of the atomic structure. Hence they can be interpreted without the need for sophisticated image simulation and the image intensity is a direct measure of the thickness of a nanocrystal. Our thickness measurements are in agreement with the predicted faceted shape of these nanocrystals. Our unique 1.3A resolution STEM has successfully resolve3d the sublattice structure of these CdSe nanocrystals. In [010] projection (the polar axis in the image plane) we can distinguish Se atom columns from Cd columns. Consequently we can study the effects of lattice polarity on the nanocrystal morphology. Furthermore, since the STEM technique does not rely on diffraction, it is superbly suited to the study of non-periodic detail, such as the surface structure of the nanocrystals. EELS measurements on individual nanocrystals indicate a significant amount (equivalet to 0.5-1 surface monolayers) of oxygen on the nanocrystals, despite processing in an inert atmosphere. Spatially resolved measurements at 7A resolution suggest a surface oxide layer. However, the uncertainty in the measurement precludes definitive assignment at this time. The source of the oxygen is under investigation as well

  12. TanDEM-X the Earth surface observation project from space level - basis and mission status

    Directory of Open Access Journals (Sweden)

    Jerzy Wiśniowski

    2015-03-01

    Full Text Available TanDEM-X is DLR (Deutsches Zentrum für Luft- und Raumfahrt the Earth surface observation project using high-resolution SAR interferometry. It opens a new era in space borne radar remote sensing. The system is based on two satellites: TerraSAR-X (TSX and TanDEM-X (TDX flying on the very close, strictly controlled orbits. This paper gives an overview of the radar technology and overview of the TanDEM-X mission concept which is based on several innovative technologies. The primary objective of the mission is to deliver a global digital elevation model (DEM with an unprecedented accuracy, which is equal to or surpass the HRTI-3 specifications (12 m posting, relative height accuracy ±2 m for slope < 20% and ±4 m for slope > 20% [8]. Beyond that, TanDEM-X provides a highly reconfigurable platform for the demonstration of new radar imaging techniques and applications.[b]Keywords[/b]: remote sensing, Bistatic SAR, digital elevation model (DEM, Helix formation, SAR interferomery, HRTI-3, synchronization

  13. UMTRA project technical assistance contractor quality assurance implementation plan for surface and ground water, Revision 2

    International Nuclear Information System (INIS)

    1995-11-01

    This document contains the Technical Assistance Contractor (TAC) Quality Assurance Implementation Plan (QAIP) for the Uranium Mill Tailings Remedial Action (UMTRA) Project. The QAIP outlines the primary requirements for integrating quality functions for TAC technical activities applied to the surface and ground water phases of the UMTRA Project. The QA program is designed to use monitoring, audit, and surveillance activities as management tools to ensure that UMTRA Project activities are carried out in amanner to protect public health and safety, promote the success of the UMTRA Project, and meet or exceed contract requirements

  14. Imaging by Electrochemical Scanning Tunneling Microscopy and Deconvolution Resolving More Details of Surfaces Nanomorphology

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov

    observed in high-resolution images of metallic nanocrystallites may be effectively deconvoluted, as to resolve more details of the crystalline morphology (see figure). Images of surface-crystalline metals indicate that more than a single atomic layer is involved in mediating the tunneling current......Upon imaging, electrochemical scanning tunneling microscopy (ESTM), scanning electrochemical micro-scopy (SECM) and in situ STM resolve information on electronic structures and on surface topography. At very high resolution, imaging processing is required, as to obtain information that relates...... to crystallographic-surface structures. Within the wide range of new technologies, those images surface features, the electrochemical scanning tunneling microscope (ESTM) provides means of atomic resolution where the tip participates actively in the process of imaging. Two metallic surfaces influence ions trapped...

  15. Correction of projective distortion in long-image-sequence mosaics without prior information

    Science.gov (United States)

    Yang, Chenhui; Mao, Hongwei; Abousleman, Glen; Si, Jennie

    2010-04-01

    Image mosaicking is the process of piecing together multiple video frames or still images from a moving camera to form a wide-area or panoramic view of the scene being imaged. Mosaics have widespread applications in many areas such as security surveillance, remote sensing, geographical exploration, agricultural field surveillance, virtual reality, digital video, and medical image analysis, among others. When mosaicking a large number of still images or video frames, the quality of the resulting mosaic is compromised by projective distortion. That is, during the mosaicking process, the image frames that are transformed and pasted to the mosaic become significantly scaled down and appear out of proportion with respect to the mosaic. As more frames continue to be transformed, important target information in the frames can be lost since the transformed frames become too small, which eventually leads to the inability to continue further. Some projective distortion correction techniques make use of prior information such as GPS information embedded within the image, or camera internal and external parameters. Alternatively, this paper proposes a new algorithm to reduce the projective distortion without using any prior information whatsoever. Based on the analysis of the projective distortion, we approximate the projective matrix that describes the transformation between image frames using an affine model. Using singular value decomposition, we can deduce the affine model scaling factor that is usually very close to 1. By resetting the image scale of the affine model to 1, the transformed image size remains unchanged. Even though the proposed correction introduces some error in the image matching, this error is typically acceptable and more importantly, the final mosaic preserves the original image size after transformation. We demonstrate the effectiveness of this new correction algorithm on two real-world unmanned air vehicle (UAV) sequences. The proposed method is

  16. Hierarchical clustering of RGB surface water images based on MIA ...

    African Journals Online (AJOL)

    2009-11-25

    Nov 25, 2009 ... similar water-related images within a testing database of 126 RGB images. .... consequently treated by SVD-based PCA and the PCA outputs partitioned into .... green. Other colours, mostly brown and grey, dominate in.

  17. Bone surface enhancement in ultrasound images using a new Doppler-based acquisition/processing method

    Science.gov (United States)

    Yang, Xu; Tang, Songyuan; Tasciotti, Ennio; Righetti, Raffaella

    2018-01-01

    Ultrasound (US) imaging has long been considered as a potential aid in orthopedic surgeries. US technologies are safe, portable and do not use radiations. This would make them a desirable tool for real-time assessment of fractures and to monitor fracture healing. However, image quality of US imaging methods in bone applications is limited by speckle, attenuation, shadow, multiple reflections and other imaging artifacts. While bone surfaces typically appear in US images as somewhat ‘brighter’ than soft tissue, they are often not easily distinguishable from the surrounding tissue. Therefore, US imaging methods aimed at segmenting bone surfaces need enhancement in image contrast prior to segmentation to improve the quality of the detected bone surface. In this paper, we present a novel acquisition/processing technique for bone surface enhancement in US images. Inspired by elastography and Doppler imaging methods, this technique takes advantage of the difference between the mechanical and acoustic properties of bones and those of soft tissues to make the bone surface more easily distinguishable in US images. The objective of this technique is to facilitate US-based bone segmentation methods and improve the accuracy of their outcomes. The newly proposed technique is tested both in in vitro and in vivo experiments. The results of these preliminary experiments suggest that the use of the proposed technique has the potential to significantly enhance the detectability of bone surfaces in noisy ultrasound images.

  18. Bone surface enhancement in ultrasound images using a new Doppler-based acquisition/processing method.

    Science.gov (United States)

    Yang, Xu; Tang, Songyuan; Tasciotti, Ennio; Righetti, Raffaella

    2018-01-17

    Ultrasound (US) imaging has long been considered as a potential aid in orthopedic surgeries. US technologies are safe, portable and do not use radiations. This would make them a desirable tool for real-time assessment of fractures and to monitor fracture healing. However, image quality of US imaging methods in bone applications is limited by speckle, attenuation, shadow, multiple reflections and other imaging artifacts. While bone surfaces typically appear in US images as somewhat 'brighter' than soft tissue, they are often not easily distinguishable from the surrounding tissue. Therefore, US imaging methods aimed at segmenting bone surfaces need enhancement in image contrast prior to segmentation to improve the quality of the detected bone surface. In this paper, we present a novel acquisition/processing technique for bone surface enhancement in US images. Inspired by elastography and Doppler imaging methods, this technique takes advantage of the difference between the mechanical and acoustic properties of bones and those of soft tissues to make the bone surface more easily distinguishable in US images. The objective of this technique is to facilitate US-based bone segmentation methods and improve the accuracy of their outcomes. The newly proposed technique is tested both in in vitro and in vivo experiments. The results of these preliminary experiments suggest that the use of the proposed technique has the potential to significantly enhance the detectability of bone surfaces in noisy ultrasound images.

  19. Surface stress mediated image force and torque on an edge dislocation

    Science.gov (United States)

    Raghavendra, R. M.; Divya, Iyer, Ganesh; Kumar, Arun; Subramaniam, Anandh

    2018-07-01

    The proximity of interfaces gives prominence to image forces experienced by dislocations. The presence of surface stress alters the traction-free boundary conditions existing on free-surfaces and hence is expected to alter the magnitude of the image force. In the current work, using a combined simulation of surface stress and an edge dislocation in a semi-infinite body, we evaluate the configurational effects on the system. We demonstrate that if the extra half-plane of the edge dislocation is parallel to the surface, the image force (glide) is not altered due to surface stress; however, the dislocation experiences a torque. The surface stress breaks the 'climb image force' symmetry, thus leading to non-equivalence between positive and negative climb. We discover an equilibrium position for the edge dislocation in the positive 'climb geometry', arising due to a competition between the interaction of the dislocation stress fields with the surface stress and the image dislocation. Torque in the climb configuration is not affected by surface stress (remains zero). Surface stress is computed using a recently developed two-scale model based on Shuttleworth's idea and image forces using a finite element model developed earlier. The effect of surface stress on the image force and torque experienced by the dislocation monopole is analysed using illustrative 3D models.

  20. 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.

  1. 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.

  2. Multi-example feature-constrained back-projection method for image super-resolution

    Institute of Scientific and Technical Information of China (English)

    Junlei Zhang; Dianguang Gai; Xin Zhang; Xuemei Li

    2017-01-01

    Example-based super-resolution algorithms,which predict unknown high-resolution image information using a relationship model learnt from known high- and low-resolution image pairs, have attracted considerable interest in the field of image processing. In this paper, we propose a multi-example feature-constrained back-projection method for image super-resolution. Firstly, we take advantage of a feature-constrained polynomial interpolation method to enlarge the low-resolution image. Next, we consider low-frequency images of different resolutions to provide an example pair. Then, we use adaptive k NN search to find similar patches in the low-resolution image for every image patch in the high-resolution low-frequency image, leading to a regression model between similar patches to be learnt. The learnt model is applied to the low-resolution high-frequency image to produce high-resolution high-frequency information. An iterative back-projection algorithm is used as the final step to determine the final high-resolution image.Experimental results demonstrate that our method improves the visual quality of the high-resolution image.

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

    DEFF Research Database (Denmark)

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

    system RASMUS. Furthermore precise scanner settings are stored for inter- and intra-observer studies. The resulting images are used for clinical evaluation. Method and materials The ultrasound scanners research interface is connected to a graphical grabber card in a Windows PC (Grabber PC). The grabber...

  4. The EUSTACE project: delivering global, daily information on surface air temperature

    Science.gov (United States)

    Ghent, D.; Rayner, N. A.

    2017-12-01

    Day-to-day variations in surface air temperature affect society in many ways; however, daily surface air temperature measurements are not available everywhere. A global daily analysis cannot be achieved with measurements made in situ alone, so incorporation of satellite retrievals is needed. To achieve this, in the EUSTACE project (2015-2018, https://www.eustaceproject.eu) we have developed an understanding of the relationships between traditional (land and marine) surface air temperature measurements and retrievals of surface skin temperature from satellite measurements, i.e. Land Surface Temperature, Ice Surface Temperature, Sea Surface Temperature and Lake Surface Water Temperature. Here we discuss the science needed to produce a fully-global daily analysis (or ensemble of analyses) of surface air temperature on the centennial scale, integrating different ground-based and satellite-borne data types. Information contained in the satellite retrievals is used to create globally-complete fields in the past, using statistical models of how surface air temperature varies in a connected way from place to place. This includes developing new "Big Data" analysis methods as the data volumes involved are considerable. We will present recent progress along this road in the EUSTACE project, i.e.: • identifying inhomogeneities in daily surface air temperature measurement series from weather stations and correcting for these over Europe; • estimating surface air temperature over all surfaces of Earth from surface skin temperature retrievals; • using new statistical techniques to provide information on higher spatial and temporal scales than currently available, making optimum use of information in data-rich eras. Information will also be given on how interested users can become involved.

  5. Technical validation of the Di3D stereophotogrammetry surface imaging system

    DEFF Research Database (Denmark)

    Winder, R.J.; Darvann, Tron Andre; McKnight, W.

    2008-01-01

    The purpose of this work was to assess the technical performance of a three-dimensional surface imaging system for geometric accuracy and maximum field of view. The system was designed for stereophotogrammetry capture of digital images from three-dimensional surfaces of the head, face, and neck...

  6. 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.

  7. Distinction of heterogeneity on Au nanostructured surface based on phase contrast imaging of atomic force microscopy

    International Nuclear Information System (INIS)

    Jung, Mi; Choi, Jeong-Woo

    2010-01-01

    The discrimination of the heterogeneity of different materials on nanostructured surfaces has attracted a great deal of interest in biotechnology as well as nanotechnology. Phase imaging through tapping mode of atomic force microscopy (TMAFM) can be used to distinguish the heterogeneity on a nanostructured surface. Nanostructures were fabricated using anodic aluminum oxide (AAO). An 11-mercaptoundecanoic acid (11-MUA) layer adsorbed onto the Au nanodots through self-assembly to improve the bio-compatibility. The Au nanostructures that were modified with 11-MUA and the concave surfaces were investigated using the TMAFM phase images to compare the heterogeneous and homogeneous nanostructured surfaces. Although the topography and phase images were taken simultaneously, the images were different. Therefore, the contrast in the TMAFM phase images revealed the different compositional materials on the heterogeneous nanostructure surface.

  8. Evaluation of noise limits to improve image processing in soft X-ray projection microscopy.

    Science.gov (United States)

    Jamsranjav, Erdenetogtokh; Kuge, Kenichi; Ito, Atsushi; Kinjo, Yasuhito; Shiina, Tatsuo

    2017-03-03

    Soft X-ray microscopy has been developed for high resolution imaging of hydrated biological specimens due to the availability of water window region. In particular, a projection type microscopy has advantages in wide viewing area, easy zooming function and easy extensibility to computed tomography (CT). The blur of projection image due to the Fresnel diffraction of X-rays, which eventually reduces spatial resolution, could be corrected by an iteration procedure, i.e., repetition of Fresnel and inverse Fresnel transformations. However, it was found that the correction is not enough to be effective for all images, especially for images with low contrast. In order to improve the effectiveness of image correction by computer processing, we in this study evaluated the influence of background noise in the iteration procedure through a simulation study. In the study, images of model specimen with known morphology were used as a substitute for the chromosome images, one of the targets of our microscope. Under the condition that artificial noise was distributed on the images randomly, we introduced two different parameters to evaluate noise effects according to each situation where the iteration procedure was not successful, and proposed an upper limit of the noise within which the effective iteration procedure for the chromosome images was possible. The study indicated that applying the new simulation and noise evaluation method was useful for image processing where background noises cannot be ignored compared with specimen images.

  9. Surface Distresses Detection of Pavement Based on Digital Image Processing

    OpenAIRE

    Ouyang , Aiguo; Luo , Chagen; Zhou , Chao

    2010-01-01

    International audience; Pavement crack is the main form of early diseases of pavement. The use of digital photography to record pavement images and subsequent crack detection and classification has undergone continuous improvements over the past decade. Digital image processing has been applied to detect the pavement crack for its advantages of large amount of information and automatic detection. The applications of digital image processing in pavement crack detection, distresses classificati...

  10. Multispectral UV imaging for surface analysis of MUPS tablets with special focus on the pellet distribution

    DEFF Research Database (Denmark)

    Novikova, Anna; Carstensen, Jens Michael; Rades, Thomas

    2016-01-01

    In the present study the applicability of multispectral UV imaging in combination with multivariate image analysis for surface evaluation of MUPS tablets was investigated with respect to the differentiation of the API pellets from the excipients matrix, estimation of the drug content as well as p...... image analysis is a promising approach for the automatic quality control of MUPS tablets during the manufacturing process....

  11. Downscaling of Aircraft, Landsat, and MODIS-bases Land Surface Temperature Images with Support Vector Machines

    Science.gov (United States)

    High spatial resolution Land Surface Temperature (LST) images are required to estimate evapotranspiration (ET) at a field scale for irrigation scheduling purposes. Satellite sensors such as Landsat 5 Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) can offer images at s...

  12. 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.)

  13. Robust surface registration using salient anatomical features for image-guided liver surgery: Algorithm and validation

    OpenAIRE

    Clements, Logan W.; Chapman, William C.; Dawant, Benoit M.; Galloway, Robert L.; Miga, Michael I.

    2008-01-01

    A successful surface-based image-to-physical space registration in image-guided liver surgery (IGLS) is critical to provide reliable guidance information to surgeons and pertinent surface displacement data for use in deformation correction algorithms. The current protocol used to perform the image-to-physical space registration involves an initial pose estimation provided by a point based registration of anatomical landmarks identifiable in both the preoperative tomograms and the intraoperati...

  14. The Application of Three-Dimensional Surface Imaging System in Plastic and Reconstructive Surgery.

    Science.gov (United States)

    Li, Yanqi; Yang, Xin; Li, Dong

    2016-02-01

    Three-dimensional (3D) surface imaging system has gained popularity worldwide in clinical application. Unlike computed tomography and magnetic resonance imaging, it has the ability to capture 3D images with both shape and texture information. This feature has made it quite useful for plastic surgeons. This review article is mainly focusing on demonstrating the current status and analyzing the future of the application of 3D surface imaging systems in plastic and reconstructive surgery.Currently, 3D surface imaging system is mainly used in plastic and reconstructive surgery to help improve the reliability of surgical planning and assessing surgical outcome objectively. There have already been reports of its using on plastic and reconstructive surgery from head to toe. Studies on facial aging process, online applications development, and so on, have also been done through the use of 3D surface imaging system.Because different types of 3D surface imaging devices have their own advantages and disadvantages, a basic knowledge of their features is required and careful thought should be taken to choose the one that best fits a surgeon's demand.In the future, by integrating with other imaging tools and the 3D printing technology, 3D surface imaging system will play an important role in individualized surgical planning, implants production, meticulous surgical simulation, operative techniques training, and patient education.

  15. 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.

  16. Surface Explorations : 3D Moving Images as Cartographies of Time

    NARCIS (Netherlands)

    Verhoeff, N.

    2016-01-01

    Moving images of travel and exploration have a long history. In this essay I will examine how the trope of navigation in 3D moving images can work towards an intimate and haptic encounter with other times and other places – elsewhen and elsewhere. The particular navigational construction of space in

  17. Dynamic PET simulator via tomographic emission projection for kinetic modeling and parametric image studies.

    Science.gov (United States)

    Häggström, Ida; Beattie, Bradley J; Schmidtlein, C Ross

    2016-06-01

    To develop and evaluate a fast and simple tool called dpetstep (Dynamic PET Simulator of Tracers via Emission Projection), for dynamic PET simulations as an alternative to Monte Carlo (MC), useful for educational purposes and evaluation of the effects of the clinical environment, postprocessing choices, etc., on dynamic and parametric images. The tool was developed in matlab using both new and previously reported modules of petstep (PET Simulator of Tracers via Emission Projection). Time activity curves are generated for each voxel of the input parametric image, whereby effects of imaging system blurring, counting noise, scatters, randoms, and attenuation are simulated for each frame. Each frame is then reconstructed into images according to the user specified method, settings, and corrections. Reconstructed images were compared to MC data, and simple Gaussian noised time activity curves (GAUSS). dpetstep was 8000 times faster than MC. Dynamic images from dpetstep had a root mean square error that was within 4% on average of that of MC images, whereas the GAUSS images were within 11%. The average bias in dpetstep and MC images was the same, while GAUSS differed by 3% points. Noise profiles in dpetstep images conformed well to MC images, confirmed visually by scatter plot histograms, and statistically by tumor region of interest histogram comparisons that showed no significant differences (p dynamic PET and parametric images, and demonstrated that it generates both images and subsequent parametric images with very similar noise properties to those of MC images, in a fraction of the time. They believe dpetstep to be very useful for generating fast, simple, and realistic results, however since it uses simple scatter and random models it may not be suitable for studies investigating these phenomena. dpetstep can be downloaded free of cost from https://github.com/CRossSchmidtlein/dPETSTEP.

  18. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y [UT Southwestern Medical Center, Dallas, TX (United States); Southern Medical University, Guangzhou (China); Yan, H; Ouyang, L; Wang, J; Jiang, S; Jia, X [UT Southwestern Medical Center, Dallas, TX (United States); Zhou, L [Southern Medical University, Guangzhou (China)

    2014-06-15

    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

  20. Improvement of image quality using interpolated projection data estimation method in SPECT

    International Nuclear Information System (INIS)

    Takaki, Akihiro; Soma, Tsutomu; Murase, Kenya; Kojima, Akihiro; Asao, Kimie; Kamada, Shinya; Matsumoto, Masanori

    2009-01-01

    General data acquisition for single photon emission computed tomography (SPECT) is performed in 90 or 60 directions, with a coarse pitch of approximately 4-6 deg for a rotation of 360 deg or 180 deg, using a gamma camera. No data between adjacent projections will be sampled under these circumstances. The aim of the study was to develop a method to improve SPECT image quality by generating lacking projection data through interpolation of data obtained with a coarse pitch such as 6 deg. The projection data set at each individual degree in 360 directions was generated by a weighted average interpolation method from the projection data acquired with a coarse sampling angle (interpolated projection data estimation processing method, IPDE method). The IPDE method was applied to the numerical digital phantom data, actual phantom data and clinical brain data with Tc-99m ethyle cysteinate dimer (ECD). All SPECT images were reconstructed by the filtered back-projection method and compared with the original SPECT images. The results confirmed that streak artifacts decreased by apparently increasing a sampling number in SPECT after interpolation and also improved signal-to-noise (S/N) ratio of the root mean square uncertainty value. Furthermore, the normalized mean square error values, compared with standard images, had similar ones after interpolation. Moreover, the contrast and concentration ratios increased their effects after interpolation. These results indicate that effective improvement of image quality can be expected with interpolation. Thus, image quality and the ability to depict images can be improved while maintaining the present acquisition time and image quality. In addition, this can be achieved more effectively than at present even if the acquisition time is reduced. (author)

  1. Pendent_Drop: An ImageJ Plugin to Measure the Surface Tension from an Image of a Pendent Drop

    Directory of Open Access Journals (Sweden)

    Adrian Daerr

    2016-01-01

    Full Text Available The pendent drop method for surface tension measurement consists in analysing the shape of an axisymmetric drop hanging from a capillary tube. This software is an add-on for the public domain image processing software ImageJ which matches a theoretical profile to the contour of a pendent drop, either interactively or by automatically minimising the mismatch. It provides an estimate of the surface tension, drop volume and surface area from the best matching parameters. It can be used in a headless setup. It is hosted on http://fiji.sc/List_of_update_sites with the source code on https://github.com/adaerr/pendent-drop

  2. A trial fabrication of activity standard surface sources and positional standard surface sources for an imaging plate system

    International Nuclear Information System (INIS)

    Sato, Yasushi; Hino, Yoshio; Yamada, Takahiro; Matsumoto, Mikio

    2003-01-01

    An imaging plate system can detect low level activity, but quantitative analysis is difficult because there are no adequate standard surface sources. A new fabrication method was developed for standard surface sources by printing on a sheet of paper using an ink-jet printer with inks in which a radioactive material was mixed. The fabricated standard surface sources had high uniformity, high positional resolution arbitrary shapes and a broad intensity range. The standard sources were used for measurement of surface activity as an application. (H. Yokoo)

  3. Mid-infrared thermal imaging for an effective mapping of surface materials and sub-surface detachments in mural paintings: integration of thermography and thermal quasi-reflectography

    Science.gov (United States)

    Daffara, C.; Parisotto, S.; Mariotti, P. I.

    2015-06-01

    Cultural Heritage is discovering how precious is thermal analysis as a tool to improve the restoration, thanks to its ability to inspect hidden details. In this work a novel dual mode imaging approach, based on the integration of thermography and thermal quasi-reflectography (TQR) in the mid-IR is demonstrated for an effective mapping of surface materials and of sub-surface detachments in mural painting. The tool was validated through a unique application: the "Monocromo" by Leonardo da Vinci in Italy. The dual mode acquisition provided two spatially aligned dataset: the TQR image and the thermal sequence. Main steps of the workflow included: 1) TQR analysis to map surface features and 2) to estimate the emissivity; 3) projection of the TQR frame on reference orthophoto and TQR mosaicking; 4) thermography analysis to map detachments; 5) use TQR to solve spatial referencing and mosaicking for the thermal-processed frames. Referencing of thermal images in the visible is a difficult aspect of the thermography technique that the dual mode approach allows to solve in effective way. We finally obtained the TQR and the thermal maps spatially referenced to the mural painting, thus providing the restorer a valuable tool for the restoration of the detachments.

  4. 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.

  5. 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

  6. 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

  7. Measuring stone surface area from a radiographic image is accurate and reproducible with the help of an imaging program.

    Science.gov (United States)

    Kurien, Abraham; Ganpule, Arvind; Muthu, V; Sabnis, R B; Desai, Mahesh

    2009-01-01

    The surface area of the stone from a radiographic image is one of the more suitable parameters defining stone bulk. The widely accepted method of measuring stone surface area is to count the number of square millimeters enclosed within a tracing of the stone outline on graph paper. This method is time consuming and cumbersome with potential for human error, especially when multiple measurements are needed. The purpose of this study was to evaluate the accuracy, efficiency, and reproducibility of a commercially available imaging program, Adobe Photoshop 7.0 for the measurement of stone surface area. The instructions to calculate area using the software are simple and easy in a Windows-based format. The accuracy of the imaging software was estimated by measuring surface areas of shapes of known mathematical areas. The efficiency and reproducibility were then evaluated from radiographs of 20 persons with radiopaque upper-tract urinary stones. The surface areas of stone images were measured using both graph paper and imaging software. Measurements were repeated after 10 days to assess the reproducibility of the techniques. The time taken to measure the area by the two methods was also assessed separately. The accuracy of the imaging software was estimated to be 98.7%. The correlation coefficient between the two methods was R(2) = 0.97. The mean percentage variation using the imaging software was 0.68%, while it was 6.36% with the graph paper. The mean time taken to measure using the image analyzer and graph paper was 1.9 +/- 0.8 minutes and 4.5 +/- 1.08 minutes, respectively (P stone surface area from radiographs compared with manual measurements using graph paper.

  8. Improved detection of chronic myocardial infarction with Fourier amplitude and phase imaging in two projections

    International Nuclear Information System (INIS)

    Akins, E.W.; Scott, E.A.; Williams, C.M.

    1987-01-01

    Twenty-seven patients with 33 chronic myocaridal infarctions underwent MR imaging and radionuclide ventriculography at rest. The radionuclide ventriculographs, in left anterior oblique (LAO) and left posterior oblique (LPO) projections, were analyzed by two independent observers by visual inspection and combined Fourier-transformed amplitude and phase imaging. Only 15 (45%) of the 33 infarctions were detected by visual inspection, but 21 (64%) were detected on the LAO Fourier-transformed images along. Thirty (91%) were detected by using both LAO and LPO Fourier-transformed images. On MR imaging, 28 (85%) of the myocardial infarctions appeared as areas of focal wall thinning. Combined Fourier-transformed amplitude and phase imaging in both LAO and LPO views discloses more myocardial infarctions than visual inspection or LAO Fourier-transformed images alone because inferior infarctions, which are frequently missed in the LAO view, are easily seen in the LPO view

  9. Surface regions of illusory images are detected with a slower processing speed than those of luminance-defined images.

    Science.gov (United States)

    Mihaylova, Milena; Manahilov, Velitchko

    2010-11-24

    Research has shown that the processing time for discriminating illusory contours is longer than for real contours. We know, however, little whether the visual processes, associated with detecting regions of illusory surfaces, are also slower as those responsible for detecting luminance-defined images. Using a speed-accuracy trade-off (SAT) procedure, we measured accuracy as a function of processing time for detecting illusory Kanizsa-type and luminance-defined squares embedded in 2D static luminance noise. The data revealed that the illusory images were detected at slower processing speed than the real images, while the points in time, when accuracy departed from chance, were not significantly different for both stimuli. The classification images for detecting illusory and real squares showed that observers employed similar detection strategies using surface regions of the real and illusory squares. The lack of significant differences between the x-intercepts of the SAT functions for illusory and luminance-modulated stimuli suggests that the detection of surface regions of both images could be based on activation of a single mechanism (the dorsal magnocellular visual pathway). The slower speed for detecting illusory images as compared to luminance-defined images could be attributed to slower processes of filling-in of regions of illusory images within the dorsal pathway.

  10. 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.

  11. WE-E-18A-11: Fluoro-Tomographic Images From Projections of On-Board Imager (OBI) While Gantry Is Moving

    Energy Technology Data Exchange (ETDEWEB)

    Yi, B; Hu, E; Yu, C; Lasio, G [Univ. of Maryland School Of Medicine, Baltimore, MD (United States)

    2014-06-15

    Purpose: A method to generate a series of fluoro-tomographic images (FTI) of the slice of interest (SOI) from the projection images of the On-board imager (OBI) while gantry is moving is developed and tested. Methods: Tomographic image via background subtraction, TIBS has been published by our group. TIBS uses a priori anatomical information from a previous CT scan to isolate a SOI from a planar kV image by factoring out the attenuations by tissues outside the SOI (background). We extended the idea to 4D TIBS, which enables to generate from the projection of different gantry angles. A set of background images for different angles are prepared. A background image at a given gantry angle is subtracted from the projection image at the same angle to generate a TIBS image. Then the TIBS image is converted to a reference angle. The 4D TIBS is the set of TIBS that originated from gantry angles other than the reference angle. Projection images of lung patients for CBCT acquisition are used to test the 4D TIBS. Results: Fluoroscopic images of a coronal plane of lung patients are acquired from the CBCT projections at different gantry angles and times. Change of morphology of hilar vessels due to breathing and heart beating are visible in the coronal plane, which are generated from the set of the projection images at gantry angles other than antero-posterior. Breathing surrogate or sorting process is not needed. Unlike tomosynthesis, FTI from 4D TIBS maintains the independence of each of the projections thereby reveals temporal variations within the SOI. Conclusion: FTI, fluoroscopic imaging of a SOI with x-ray projections, directly generated from the x-ray projection images at different gantry angles is tested with a lung case and proven feasible. This technique can be used for on-line imaging of moving targets. NIH Grant R01CA133539.

  12. Projectables

    DEFF Research Database (Denmark)

    Rasmussen, Troels A.; Merritt, Timothy R.

    2017-01-01

    CNC cutting machines have become essential tools for designers and architects enabling rapid prototyping, model-building and production of high quality components. Designers often cut from new materials, discarding the irregularly shaped remains. We introduce ProjecTables, a visual augmented...... reality system for interactive packing of model parts onto sheet materials. ProjecTables enables designers to (re)use scrap materials for CNC cutting that would have been previously thrown away, at the same time supporting aesthetic choices related to wood grain, avoiding surface blemishes, and other...... relevant material properties. We conducted evaluations of ProjecTables with design students from Aarhus School of Architecture, demonstrating that participants could quickly and easily place and orient model parts reducing material waste. Contextual interviews and ideation sessions led to a deeper...

  13. Greenland ice sheet surface mass balance: evaluating simulations and making projections with regional climate models

    NARCIS (Netherlands)

    Rae, J.G.L.; Aðalgeirsdóttir, G.; Edwards, T.L.; Fettweis, X.; Gregory, J.M.; Hewitt, H.T.; Lowe, J.A.; Lucas-Picher, P.; Mottram, R.H.; Payne, A.J.; Ridley, J.K.; Shannon, S.R.; van de Berg, W.J.; van de Wal, R.S.W.; van den Broeke, M.R.

    2012-01-01

    Four high-resolution regional climate models (RCMs) have been set up for the area of Greenland, with the aim of providing future projections of Greenland ice sheet surface mass balance (SMB), and its contribution to sea level rise, with greater accuracy than is possible from coarser-resolution

  14. 75 FR 75532 - Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report

    Science.gov (United States)

    2010-12-03

    ...] Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report AGENCY: Federal Highway... participating in the Pilot Program, 23 U.S.C. 327(g) mandates semiannual audits during each of the first 2 years of State participation. This notice announces and solicits comments on the fifth audit report for the...

  15. 76 FR 5237 - Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report

    Science.gov (United States)

    2011-01-28

    ...] Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report AGENCY: Federal Highway... participating in the Pilot Program, 23 U.S.C. 327(g) mandates semiannual audits during each of the first 2 years of State participation. This final report presents the findings from the fifth FHWA audit of the...

  16. 77 FR 26355 - Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report

    Science.gov (United States)

    2012-05-03

    ...] Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report AGENCY: Federal Highway... participating in the Pilot Program, 23 U.S.C. 327(g) mandates semiannual audits during each of the first 2 years of State participation. This final report presents the findings from the sixth FHWA audit of the...

  17. The Pilot Project 'Optical Image Correlation' of the ESA Geohazards Thematic Exploitation Platform (GTEP)

    Science.gov (United States)

    Stumpf, André; Malet, Jean-Philippe

    2016-04-01

    Since more than 20 years, "Earth Observation" (EO) satellites developed or operated by ESA have provided a wealth of data. In the coming years, the Sentinel missions, along with the Copernicus Contributing Missions as well as Earth Explorers and other, Third Party missions will provide routine monitoring of our environment at the global scale, thereby delivering an unprecedented amount of data. While the availability of the growing volume of environmental data from space represents a unique opportunity for science, general R&D, and applications, it also poses major challenges to fully exploit the potential of archived and daily incoming datasets. Those challenges do not only comprise the discovery, access, processing, and visualization of large data volumes but also an increasing diversity of data sources and end users from different fields (e.g. EO, in-situ monitoring, and modeling). In this context, the GTEP (Geohazards Thematic Exploitation Platform) initiative aims to build an operational distributed processing platform to maximize the exploitation of EO data from past and future satellite missions for the detection and monitoring of natural hazards. This presentation focuses on the "Optical Image Correlation" Pilot Project (funded by ESA within the GTEP platform) which objectives are to develop an easy-to-use, flexible and distributed processing chain for: 1) the automated reconstruction of surface Digital Elevation Models from stereo (and tristereo) pairs of Spot 6/7 and Pléiades satellite imagery, 2) the creation of ortho-images (panchromatic and multi-spectral) of Landsat 8, Sentinel-2, Spot 6/7 and Pléiades scenes, 3) the calculation of horizontal (E-N) displacement vectors based on sub-pixel image correlation. The processing chains is being implemented on the GEP cloud-based (Hadoop, MapReduce) environment and designed for analysis of surface displacements at local to regional scale (10-1000 km2) targeting in particular co-seismic displacement and slow

  18. Image distortion due to refraction by planar surfaces

    International Nuclear Information System (INIS)

    Arizaga, R; Cap, N; Rabal, H; Trivi, M

    2010-01-01

    The term 'apparent depth' is commonly treated in textbooks as an issue easily understandable from the point of view of paraxial optical geometrical optics. Nevertheless, everyday life tells us that most of the time the observation of objects immersed in water is made under a great range of visual angles where the paraxial approximation is not valid. Here we developed a non-paraxial treatment to calculate the position and shape of the image of objects immersed in liquids of different refractive indices. The approach was focused on the parametric positions of the images of a single point at different viewing angles. Then we calculated how the image of an extended object is distorted. By using the Matlab software, it is possible to visualize the images for different geometrical conditions. We also include the analysis for refractive index with negative values as is the case of metamaterials.

  19. Image distortion due to refraction by planar surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Arizaga, R; Cap, N; Rabal, H; Trivi, M [Centro de Investigaciones Opticas (CONICET La Plata-CIC) and OPTIMO Dto de Ciencias Basicas, Fac. de Ingenieria UNLP, PO Box 3, 1897 Gonnet, La Plata (Argentina)

    2010-01-15

    The term 'apparent depth' is commonly treated in textbooks as an issue easily understandable from the point of view of paraxial optical geometrical optics. Nevertheless, everyday life tells us that most of the time the observation of objects immersed in water is made under a great range of visual angles where the paraxial approximation is not valid. Here we developed a non-paraxial treatment to calculate the position and shape of the image of objects immersed in liquids of different refractive indices. The approach was focused on the parametric positions of the images of a single point at different viewing angles. Then we calculated how the image of an extended object is distorted. By using the Matlab software, it is possible to visualize the images for different geometrical conditions. We also include the analysis for refractive index with negative values as is the case of metamaterials.

  20. Application of image recognition algorithms for statistical description of nano- and microstructured surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Mărăscu, V.; Dinescu, G. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, Bucharest– Magurele (Romania); Faculty of Physics, University of Bucharest, 405 Atomistilor Street, Bucharest-Magurele (Romania); Chiţescu, I. [Faculty of Mathematics and Computer Science, University of Bucharest, 14 Academiei Street, Bucharest (Romania); Barna, V. [Faculty of Physics, University of Bucharest, 405 Atomistilor Street, Bucharest-Magurele (Romania); Ioniţă, M. D.; Lazea-Stoyanova, A.; Mitu, B., E-mail: mitub@infim.ro [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, Bucharest– Magurele (Romania)

    2016-03-25

    In this paper we propose a statistical approach for describing the self-assembling of sub-micronic polystyrene beads on silicon surfaces, as well as the evolution of surface topography due to plasma treatments. Algorithms for image recognition are used in conjunction with Scanning Electron Microscopy (SEM) imaging of surfaces. In a first step, greyscale images of the surface covered by the polystyrene beads are obtained. Further, an adaptive thresholding method was applied for obtaining binary images. The next step consisted in automatic identification of polystyrene beads dimensions, by using Hough transform algorithm, according to beads radius. In order to analyze the uniformity of the self–assembled polystyrene beads, the squared modulus of 2-dimensional Fast Fourier Transform (2- D FFT) was applied. By combining these algorithms we obtain a powerful and fast statistical tool for analysis of micro and nanomaterials with aspect features regularly distributed on surface upon SEM examination.

  1. Application of image recognition algorithms for statistical description of nano- and microstructured surfaces

    International Nuclear Information System (INIS)

    Mărăscu, V.; Dinescu, G.; Chiţescu, I.; Barna, V.; Ioniţă, M. D.; Lazea-Stoyanova, A.; Mitu, B.

    2016-01-01

    In this paper we propose a statistical approach for describing the self-assembling of sub-micronic polystyrene beads on silicon surfaces, as well as the evolution of surface topography due to plasma treatments. Algorithms for image recognition are used in conjunction with Scanning Electron Microscopy (SEM) imaging of surfaces. In a first step, greyscale images of the surface covered by the polystyrene beads are obtained. Further, an adaptive thresholding method was applied for obtaining binary images. The next step consisted in automatic identification of polystyrene beads dimensions, by using Hough transform algorithm, according to beads radius. In order to analyze the uniformity of the self–assembled polystyrene beads, the squared modulus of 2-dimensional Fast Fourier Transform (2- D FFT) was applied. By combining these algorithms we obtain a powerful and fast statistical tool for analysis of micro and nanomaterials with aspect features regularly distributed on surface upon SEM examination.

  2. Measurement of inter and intra fraction organ motion in radiotherapy using cone beam CT projection images

    International Nuclear Information System (INIS)

    Marchant, T E; Amer, A M; Moore, C J

    2008-01-01

    A method is presented for extraction of intra and inter fraction motion of seeds/markers within the patient from cone beam CT (CBCT) projection images. The position of the marker is determined on each projection image and fitted to a function describing the projection of a fixed point onto the imaging panel at different gantry angles. The fitted parameters provide the mean marker position with respect to the isocentre. Differences between the theoretical function and the actual projected marker positions are used to estimate the range of intra fraction motion and the principal motion axis in the transverse plane. The method was validated using CBCT projection images of a static marker at known locations and of a marker moving with known amplitude. The mean difference between actual and measured motion range was less than 1 mm in all directions, although errors of up to 5 mm were observed when large amplitude motion was present in an orthogonal direction. In these cases it was possible to calculate the range of motion magnitudes consistent with the observed marker trajectory. The method was shown to be feasible using clinical CBCT projections of a pancreas cancer patient

  3. Fringe projection application for surface variation analysis on helical shaped silicon breast

    Science.gov (United States)

    Vairavan, R.; Ong, N. R.; Sauli, Z.; Shahimin, M. M.; Kirtsaeng, S.; Sakuntasathien, S.; Alcain, J. B.; Paitong, P.; Retnasamy, V.

    2017-09-01

    Breast carcinoma is rated as a second collective cause of cancer associated death among adult females. Detection of the disease at an early stage would enhance the chance for survival. Established detection methods such as mammography, ultrasound and MRI are classified as non invasive breast cancer detection modality, but however they are not entire non-invasive as physical contact still occurs to the breast. Thus requirement for a complete non invasive and non contact is evident. Therefore, in this work, a novel application of digital fringe projection for early detection of breast cancer based on breast surface analysis is reported. Phase shift fringe projection technique and pixel tracing method was utilized to analyze the breast surface change due to the incidence of breast lump. Results have shown that the digital fringe projection is capable in detecting the existence of 1 cm sized lump within the breast sample.

  4. 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.

  5. A technique for the geometric modeling of underground surfaces: Nevada Nuclear Waste Storage Investigations Project

    International Nuclear Information System (INIS)

    Williams, R.L.

    1988-03-01

    There is a need within the Nevada Nuclear Waste Storage Investigation (NNWSI) project to develop three-dimensional surface definitions for the subterranean stratigraphies at Yucca Mountain, Nevada. The nature of the data samples available to the project require an interpolation technique that can perform well with sparse and irregularly spaced data. Following an evaluation of the relevant existing methods, a new technique, Multi-Kernel Modulation (MKM), is presented. MKM interpolates sparse and irregularly spaced data by modulating a polynomial trend surface with a linear summation of regular surfaces (kernels). A perspective discussion of MKM, Kriging, and Multiquadric Analysis reveals that MKM has the advantage of simplicity and efficiency when used with sparse samples. An example of the use of MKM to model a complex topography is presented. 24 refs., 6 figs., 2 tabs

  6. Validation of phalanx bone three-dimensional surface segmentation from computed tomography images using laser scanning

    Energy Technology Data Exchange (ETDEWEB)

    DeVries, Nicole A.; Gassman, Esther E.; Kallemeyn, Nicole A. [The University of Iowa, Department of Biomedical Engineering, Center for Computer Aided Design, Iowa City, IA (United States); Shivanna, Kiran H. [The University of Iowa, Center for Computer Aided Design, Iowa City, IA (United States); Magnotta, Vincent A. [The University of Iowa, Department of Biomedical Engineering, Department of Radiology, Center for Computer Aided Design, Iowa City, IA (United States); Grosland, Nicole M. [The University of Iowa, Department of Biomedical Engineering, Department of Orthopaedics and Rehabilitation, Center for Computer Aided Design, Iowa City, IA (United States)

    2008-01-15

    To examine the validity of manually defined bony regions of interest from computed tomography (CT) scans. Segmentation measurements were performed on the coronal reformatted CT images of the three phalanx bones of the index finger from five cadaveric specimens. Two smoothing algorithms (image-based and Laplacian surface-based) were evaluated to determine their ability to represent accurately the anatomic surface. The resulting surfaces were compared with laser surface scans of the corresponding cadaveric specimen. The average relative overlap between two tracers was 0.91 for all bones. The overall mean difference between the manual unsmoothed surface and the laser surface scan was 0.20 mm. Both image-based and Laplacian surface-based smoothing were compared; the overall mean difference for image-based smoothing was 0.21 mm and 0.20 mm for Laplacian smoothing. This study showed that manual segmentation of high-contrast, coronal, reformatted, CT datasets can accurately represent the true surface geometry of bones. Additionally, smoothing techniques did not significantly alter the surface representations. This validation technique should be extended to other bones, image segmentation and spatial filtering techniques. (orig.)

  7. Validation of phalanx bone three-dimensional surface segmentation from computed tomography images using laser scanning

    International Nuclear Information System (INIS)

    DeVries, Nicole A.; Gassman, Esther E.; Kallemeyn, Nicole A.; Shivanna, Kiran H.; Magnotta, Vincent A.; Grosland, Nicole M.

    2008-01-01

    To examine the validity of manually defined bony regions of interest from computed tomography (CT) scans. Segmentation measurements were performed on the coronal reformatted CT images of the three phalanx bones of the index finger from five cadaveric specimens. Two smoothing algorithms (image-based and Laplacian surface-based) were evaluated to determine their ability to represent accurately the anatomic surface. The resulting surfaces were compared with laser surface scans of the corresponding cadaveric specimen. The average relative overlap between two tracers was 0.91 for all bones. The overall mean difference between the manual unsmoothed surface and the laser surface scan was 0.20 mm. Both image-based and Laplacian surface-based smoothing were compared; the overall mean difference for image-based smoothing was 0.21 mm and 0.20 mm for Laplacian smoothing. This study showed that manual segmentation of high-contrast, coronal, reformatted, CT datasets can accurately represent the true surface geometry of bones. Additionally, smoothing techniques did not significantly alter the surface representations. This validation technique should be extended to other bones, image segmentation and spatial filtering techniques. (orig.)

  8. Comparison of surface contour and volumetric three-dimensional imaging of the musculoskeletal system

    International Nuclear Information System (INIS)

    Guilford, W.B.; Ullrich, C.G.; Moore, T.

    1988-01-01

    Both surface contour and volumetric three-dimensional image processing from CT data can provide accurate demonstration of skeletal anatomy. While realistic, surface contour images may obscure fine detail such as nondisplaced fractures, and thin bone may disappear. Volumetric processing can provide high detail, but the transparency effect is unnatural and may yield a confusing image. Comparison of both three-dimensional modes is presented to demonstrate those findings best shown with each and to illustrate helpful techniques to improve volumetric display, such as disarticulation of unnecessary anatomy, short-angle repeating rotation (dithering), and image combination into overlay displays

  9. Multi-detector and systematic imaging system designed and developed within the New AGLAE project

    International Nuclear Information System (INIS)

    Pichon, L.; Pacheco, C.; Moignard, B.; Lemasson, Q.; Guillou, T.; Walter, Ph

    2013-01-01

    Full text: The New AGLAE project aims to establish a world-class facility for non invasive analysis of Cultural Heritage materials. One of the objectives of the New AGLAE project is to increase the x-ray measurement detection, enabling to reduce the beam intensity thus the interaction with sensitive artworks by a ten. Multidisciplinary, the New AGLAE project will provide an exceptional and multipurpose beam line with a performance in spatial resolution, beam stability and a capability of multi-particle detection much higher than for the previous facility. The New AGLAE will give fundamental elements for the understanding of the structure of materials, their composition, properties, and change over time. One of the objectives of this project is to design and set up a new data acquisition system. To reach that purpose, the surface and the number of PIXE detectors have been increased. Indeed, a 10 mm 2 and a 30 mm 3 Si(Li) detectors respectively dedicated to low and high energy measurements, were replaced by a cluster of five 50 mm 2 S.D.D. detectors. If this multi detector enables to decrease the intensity of the incident beam by one order of magnitude, involving less irradiation during the analysis, it can also provide large and/or fast maps. So as to digital the preamp pulses obtained from the detectors, a custom Digital X-ray Processor provides both digital data and control signals compatible to a multiparameter multichannel system. This multiparameter system saves each event from x-ray, gamma and particle detectors and simultaneously the X, Y positions of the beam on the sample as a list file. Furthermore, to draw several-cm-sized maps with a 20/40μm resolution, the scanning of the area originally combines a fast vertical magnetic deflection of the beam and a mechanical movement of the target. To process the data, several homemade software have been developed or updated so as to rebuild any matrix of spectra, to re-bin maps, to process a series of single spectra

  10. 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.

  11. Surface Reconstruction and Image Enhancement via $L^1$-Minimization

    KAUST Repository

    Dobrev, Veselin; Guermond, Jean-Luc; Popov, Bojan

    2010-01-01

    A surface reconstruction technique based on minimization of the total variation of the gradient is introduced. Convergence of the method is established, and an interior-point algorithm solving the associated linear programming problem is introduced

  12. Adsorbed radioactivity and radiographic imaging of surfaces of stainless steel and titanium

    Science.gov (United States)

    Jung, Haijo

    1997-11-01

    Type 304 stainless steel used for typical surface materials of spent fuel shipping casks and titanium were exposed in the spent fuel storage pool of a typical PWR power plant. Adsorption characteristics, effectiveness of decontamination by water cleaning and by electrocleaning, and swipe effectiveness on the metal surfaces were studied. A variety of environmental conditions had been manipulated to stimulate the potential 'weeping' phenomenon that often occurs with spent fuel shipping casks during transit. In a previous study, few heterogeneous effects of adsorbed contamination onto metal surfaces were observed. Radiographic images of cask surfaces were made in this study and showed clearly heterogeneous activity distributions. Acquired radiographic images were digitized and further analyzed with an image analysis computer package and compared to calibrated images by using standard sources. The measurements of activity distribution by using the radiographic image method were consistent with that using a HPGe detector. This radiographic image method was used to study the effects of electrocleaning for total and specified areas. The Modulation Transfer Function (MTF) of a film-screen system in contact with a radioactive metal surface was studied with neutron activated gold foils and showed more broad resolution properties than general diagnostic x-ray film-screen systems. Microstructure between normal areas and hot spots showed significant differences, and one hot spot appearing as a dot on the film image consisted of several small hot spots (about 10 μm in diameter). These hot spots were observed as structural defects of the metal surfaces.

  13. High-resolution projections of surface water availability for Tasmania, Australia

    Directory of Open Access Journals (Sweden)

    J. C. Bennett

    2012-05-01

    Full Text Available Changes to streamflows caused by climate change may have major impacts on the management of water for hydro-electricity generation and agriculture in Tasmania, Australia. We describe changes to Tasmanian surface water availability from 1961–1990 to 2070–2099 using high-resolution simulations. Six fine-scale (∼10 km2 simulations of daily rainfall and potential evapotranspiration are generated with the CSIRO Conformal Cubic Atmospheric Model (CCAM, a variable-resolution regional climate model (RCM. These variables are bias-corrected with quantile mapping and used as direct inputs to the hydrological models AWBM, IHACRES, Sacramento, SIMHYD and SMAR-G to project streamflows.

    The performance of the hydrological models is assessed against 86 streamflow gauges across Tasmania. The SIMHYD model is the least biased (median bias = −3% while IHACRES has the largest bias (median bias = −22%. We find the hydrological models that best simulate observed streamflows produce similar streamflow projections.

    There is much greater variation in projections between RCM simulations than between hydrological models. Marked decreases of up to 30% are projected for annual runoff in central Tasmania, while runoff is generally projected to increase in the east. Daily streamflow variability is projected to increase for most of Tasmania, consistent with increases in rainfall intensity. Inter-annual variability of streamflows is projected to increase across most of Tasmania.

    This is the first major Australian study to use high-resolution bias-corrected rainfall and potential evapotranspiration projections as direct inputs to hydrological models. Our study shows that these simulations are capable of producing realistic streamflows, allowing for increased confidence in assessing future changes to surface water variability.

  14. Ocean Surface Current Vectors from MODIS Terra/Aqua Sea Surface Temperature Image Pairs, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellites that record imagery of the same sea surface area, at times separated by a few hours, can be used to estimate ocean surface velocity fields based on the...

  15. Four-channel surface coil array for sequential CW-EPR image acquisition

    Science.gov (United States)

    Enomoto, Ayano; Emoto, Miho; Fujii, Hirotada; Hirata, Hiroshi

    2013-09-01

    This article describes a four-channel surface coil array to increase the area of visualization for continuous-wave electron paramagnetic resonance (CW-EPR) imaging. A 776-MHz surface coil array was constructed with four independent surface coil resonators and three kinds of switches. Control circuits for switching the resonators were also built to sequentially perform EPR image acquisition for each resonator. The resonance frequencies of the resonators were shifted using PIN diode switches to decouple the inductively coupled coils. To investigate the area of visualization with the surface coil array, three-dimensional EPR imaging was performed using a glass cell phantom filled with a solution of nitroxyl radicals. The area of visualization obtained with the surface coil array was increased approximately 3.5-fold in comparison to that with a single surface coil resonator. Furthermore, to demonstrate the applicability of this surface coil array to animal imaging, three-dimensional EPR imaging was performed in a living mouse with an exogenously injected nitroxyl radical imaging agent.

  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. Future projections of the Greenland ice sheet energy balance driving the surface melt

    Directory of Open Access Journals (Sweden)

    B. Franco

    2013-01-01

    Full Text Available In this study, simulations at 25 km resolution are performed over the Greenland ice sheet (GrIS throughout the 20th and 21st centuries, using the regional climate model MAR forced by four RCP scenarios from three CMIP5 global circulation models (GCMs, in order to investigate the projected changes of the surface energy balance (SEB components driving the surface melt. Analysis of 2000–2100 melt anomalies compared to melt results over 1980–1999 reveals an exponential relationship of the GrIS surface melt rate simulated by MAR to the near-surface air temperature (TAS anomalies, mainly due to the surface albedo positive feedback associated with the extension of bare ice areas in summer. On the GrIS margins, the future melt anomalies are preferentially driven by stronger sensible heat fluxes, induced by enhanced warm air advection over the ice sheet. Over the central dry snow zone, the surface albedo positive feedback induced by the increase in summer melt exceeds the negative feedback of heavier snowfall for TAS anomalies higher than 4 °C. In addition to the incoming longwave flux increase associated with the atmosphere warming, GCM-forced MAR simulations project an increase of the cloud cover decreasing the ratio of the incoming shortwave versus longwave radiation and dampening the albedo feedback. However, it should be noted that this trend in the cloud cover is contrary to that simulated by ERA-Interim–forced MAR for recent climate conditions, where the observed melt increase since the 1990s seems mainly to be a consequence of more anticyclonic atmospheric conditions. Finally, no significant change is projected in the length of the melt season, which highlights the importance of solar radiation absorbed by the ice sheet surface in the melt SEB.

  18. Effects of surface-mapping corrections and synthetic-aperture focusing techniques on ultrasonic imaging

    International Nuclear Information System (INIS)

    Barna, B.A.; Johnson, J.A.

    1981-01-01

    Improvements in ultrasonic imaging that can be obtained using algorithms that map the surface of targets are evaluated. This information is incorporated in the application of synthetic-aperture focusing techniques which also have the potential to improve image resolution. Images obtained using directed-beam (flat) transducers and the focused transducers normally used for synthetic-aperture processing are quantitatively compared by using no processing, synthetic-aperture processing with no corrections for surface variations, and synthetic-aperture processing with surface mapping. The unprocessed images have relatively poor lateral resolutions because echoes from two adjacent reflectors show interference effects which prevent their identification even if the spacing is larger than the single-hole resolution. The synthetic-aperture-processed images show at least a twofold improvement in lateral resolution and greatly reduced interference effects in multiple-hole images compared to directed-beam images. Perhaps more importantly, in images of test blocks with substantial surface variations portions of the image are displaced from their actual positions by several wavelengths. To correct for this effect an algorithm has been developed for calculating the surface variations. The corrected images produced using this algorithm are accurate within the experimental error. In addition, the same algorithm, when applied to the directed-beam data, produced images that are not only accurately positioned, but that also have a resolution comparable to conventional synthetic-aperture-processed images obtained from focused-transducer data. This suggests that using synthetic-aperture processing on the type of data normally collected during directed-beam ultrasonic inspections would eliminate the need to rescan for synthetic-aperture enhancement

  19. Restoration of the analytically reconstructed OpenPET images by the method of convex projections

    Energy Technology Data Exchange (ETDEWEB)

    Tashima, Hideaki; Murayama, Hideo; Yamaya, Taiga [National Institute of Radiological Sciences, Chiba (Japan); Katsunuma, Takayuki; Suga, Mikio [Chiba Univ. (Japan). Graduate School of Engineering; Kinouchi, Shoko [National Institute of Radiological Sciences, Chiba (Japan); Chiba Univ. (Japan). Graduate School of Engineering; Obi, Takashi [Tokyo Institute of Technology (Japan). Interdisciplinary Graduate School of Science and Engineering; Kudo, Hiroyuki [Tsukuba Univ. (Japan). Graduate School of Systems and Information Engineering

    2011-07-01

    We have proposed the OpenPET geometry which has gaps between detector rings and physically opened field-of-view. The image reconstruction of the OpenPET is classified into an incomplete problem because it does not satisfy the Orlov's condition. Even so, the simulation and experimental studies have shown that applying iterative methods such as the maximum likelihood expectation maximization (ML-EM) algorithm successfully reconstruct images in the gap area. However, the imaging process of the iterative methods in the OpenPET imaging is not clear. Therefore, the aim of this study is to analytically analyze the OpenPET imaging and estimate implicit constraints involved in the iterative methods. To apply explicit constraints in the OpenPET imaging, we used the method of convex projections for restoration of the images reconstructed by the analytical way in which low-frequency components are lost. Numerical simulations showed that the similar restoration effects are involved both in the ML-EM and the method of convex projections. Therefore, the iterative methods have advantageous effect of restoring lost frequency components of the OpenPET imaging. (orig.)

  20. Text extraction method for historical Tibetan document images based on block projections

    Science.gov (United States)

    Duan, Li-juan; Zhang, Xi-qun; Ma, Long-long; Wu, Jian

    2017-11-01

    Text extraction is an important initial step in digitizing the historical documents. In this paper, we present a text extraction method for historical Tibetan document images based on block projections. The task of text extraction is considered as text area detection and location problem. The images are divided equally into blocks and the blocks are filtered by the information of the categories of connected components and corner point density. By analyzing the filtered blocks' projections, the approximate text areas can be located, and the text regions are extracted. Experiments on the dataset of historical Tibetan documents demonstrate the effectiveness of the proposed method.

  1. The IAEA research project on improvement of safety assessment methodologies for near surface disposal facilities

    International Nuclear Information System (INIS)

    Torres-Vidal, C.; Graham, D.; Batandjieva, B.

    2002-01-01

    The International Atomic Energy Agency (IAEA) Research Coordinated Project on Improvement of Safety Assessment Methodologies for Near Surface Disposal Facilities (ISAM) was launched in November 1997 and it has been underway for three years. The ISAM project was developed to provide a critical evaluation of the approaches and tools used in long-term safety assessment of near surface repositories. It resulted in the development of a harmonised approach and illustrated its application by way of three test cases - vault, borehole and Radon (a particular range of repository designs developed within the former Soviet Union) type repositories. As a consequence, the ISAM project had over 70 active participants and attracted considerable interest involving around 700 experts from 72 Member States. The methodology developed, the test cases, the main lessons learnt and the conclusions have been documented and will be published in the form of an IAEA TECDOC. This paper presents the work of the IAEA on improvement of safety assessment methodologies for near surface waste disposal facilities and the application of these methodologies for different purposes in the individual stages of the repository development. The paper introduces the main objectives, activities and outcome of the ISAM project and summarizes the work performed by the six working groups within the ISAM programme, i.e. Scenario Generation and Justification, Modelling, Confidence Building, Vault, Radon Type Facility and Borehole test cases. (author)

  2. 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)

  3. 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.)

  4. Image reconstruction from projections and its application in emission computer tomography

    International Nuclear Information System (INIS)

    Kuba, Attila; Csernay, Laszlo

    1989-01-01

    Computer tomography is an imaging technique for producing cross sectional images by reconstruction from projections. Its two main branches are called transmission and emission computer tomography, TCT and ECT, resp. After an overview of the theory and practice of TCT and ECT, the first Hungarian ECT type MB 9300 SPECT consisting of a gamma camera and Ketronic Medax N computer is described, and its applications to radiological patient observations are discussed briefly. (R.P.) 28 refs.; 4 figs

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

    OpenAIRE

    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 investigat...

  6. Imaging of Ground Ice with Surface-Based Geophysics

    Science.gov (United States)

    2015-10-01

    terrains. Electrical Resistivity Tomography (ERT), in particular, has been effective for imaging ground ice. ERT measures the ability of materials to...13 2.2.1 Electrical resistivity tomography (ERT...Engineer Research and Development Center ERT Electrical Resistivity Tomography GPS Global Positioning System LiDAR Light Detection and Ranging SIPRE

  7. Imaging Freeform Optical Systems Designed with NURBS Surfaces

    Science.gov (United States)

    2015-12-01

    reflective, anastigmat 1 Introduction The imaging freeform optical systems described here are designed using non-uniform rational basis-spline (NURBS...code, but to succeed in designing NURBS freeform optical systems an optimization code is required. The motivation for developing the optical design

  8. Spatial characterization of nanotextured surfaces by visual color imaging

    DEFF Research Database (Denmark)

    Feidenhans'l, Nikolaj Agentoft; Murthy, Swathi; Madsen, Morten H.

    2016-01-01

    We present a method using an ordinary color camera to characterize nanostructures from the visual color of the structures. The method provides a macroscale overview image from which micrometer-sized regions can be analyzed independently, hereby revealing long-range spatial variations...

  9. Fluorescence Exclusion: A Simple Method to Assess Projected Surface, Volume and Morphology of Red Blood Cells Stored in Blood Bank

    Directory of Open Access Journals (Sweden)

    Camille Roussel

    2018-05-01

    Full Text Available Red blood cells (RBC ability to circulate is closely related to their surface area-to-volume ratio. A decrease in this ratio induces a decrease in RBC deformability that can lead to their retention and elimination in the spleen. We recently showed that a subpopulation of “small RBC” with reduced projected surface area accumulated upon storage in blood bank concentrates, but data on the volume of these altered RBC are lacking. So far, single cell measurement of RBC volume has remained a challenging task achieved by a few sophisticated methods some being subject to potential artifacts. We aimed to develop a reproducible and ergonomic method to assess simultaneously RBC volume and morphology at the single cell level. We adapted the fluorescence exclusion measurement of volume in nucleated cells to the measurement of RBC volume. This method requires no pre-treatment of the cell and can be performed in physiological or experimental buffer. In addition to RBC volume assessment, brightfield images enabling a precise definition of the morphology and the measurement of projected surface area can be generated simultaneously. We first verified that fluorescence exclusion is precise, reproducible and can quantify volume modifications following morphological changes induced by heating or incubation in non-physiological medium. We then used the method to characterize RBC stored for 42 days in SAG-M in blood bank conditions. Simultaneous determination of the volume, projected surface area and morphology allowed to evaluate the surface area-to-volume ratio of individual RBC upon storage. We observed a similar surface area-to-volume ratio in discocytes (D and echinocytes I (EI, which decreased in EII (7% and EIII (24%, sphero-echinocytes (SE; 41% and spherocytes (S; 47%. If RBC dimensions determine indeed the ability of RBC to cross the spleen, these modifications are expected to induce the rapid splenic entrapment of the most morphologically altered RBC

  10. Factors affecting projected Arctic surface shortwave heating and albedo change in coupled climate models.

    Science.gov (United States)

    Holland, Marika M; Landrum, Laura

    2015-07-13

    We use a large ensemble of simulations from the Community Earth System Model to quantify simulated changes in the twentieth and twenty-first century Arctic surface shortwave heating associated with changing incoming solar radiation and changing ice conditions. For increases in shortwave absorption associated with albedo reductions, the relative influence of changing sea ice surface properties and changing sea ice areal coverage is assessed. Changes in the surface sea ice properties are associated with an earlier melt season onset, a longer snow-free season and enhanced surface ponding. Because many of these changes occur during peak solar insolation, they have a considerable influence on Arctic surface shortwave heating that is comparable to the influence of ice area loss in the early twenty-first century. As ice area loss continues through the twenty-first century, it overwhelms the influence of changes in the sea ice surface state, and is responsible for a majority of the net shortwave increases by the mid-twenty-first century. A comparison with the Arctic surface albedo and shortwave heating in CMIP5 models indicates a large spread in projected twenty-first century change. This is in part related to different ice loss rates among the models and different representations of the late twentieth century ice albedo and associated sea ice surface state. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  11. UMTRA Surface Project management action process document. Final report: Revision 1

    International Nuclear Information System (INIS)

    1996-04-01

    A critical mission of the US Department of Energy (DOE) is the planning, implementation, and completion of environmental restoration (ER) programs at facilities that were operated by or in support of the former Atomic Energy Commission (AEC) from the late 1940s into the 1970s. Among these facilities are the 24 former uranium mill sites designed in the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978 (42 USC section 7901 et seq.) Title 1 of the UMTRCA authorized the DOE to undertake remedial actions at these designated sites and associated vicinity properties (VP), which contain uranium mill tailings and other residual radioactive materials (RRM) derived from the processing sites. Title 2 of the UMTRCA addresses uranium mill sites that were licensed at the time the UMTRCA was enacted. Cleanup of these Title 2 sites is the responsibility of the licensees. The cleanup of the Title 1 sites has been split into two separate projects: the Surface Project, which deals with the mill buildings, tailings, and contaminated soils at the sites and VPs; and the Ground Water Project, which is limited to the contaminated ground water at the sites. This management action process (MAP) document discusses the Uranium Mill Tailings Remedial Action (UMTRA) Surface Project only; a separate MAP document has been prepared for the UMTRA Ground Water Project

  12. Ptychographic x-ray imaging of surfaces on crystal truncation rod

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Chenhui; Barbour, Andi; Liu, Yaohua; You, Hoydoo, E-mail: hyou@anl.gov [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Harder, Ross; Xu, Ruqing [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Diaz, Ana; Menzel, Andreas [Paul Scherrer Institut, Villigen PSI 5232 (Switzerland); Komanicky, Vladimir [Faculty of Sciences, Safarik University, Kosice 04154 (Slovakia); Huang, Xiaojing [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973 (United States); Pierce, Michael S. [School of Physics and Astronomy, Rochester Institute of Technology, Rochester, New York 14623 (United States)

    2015-03-09

    Ptychography is a high-resolution imaging technique, which does not require lenses for image magnification and which provides phase contrast with high sensitivity. Here, we propose to use x-ray ptychography for the imaging of surface structure in crystalline samples. We show that ptychography can be used to image atomic step structures using coherent diffraction patterns recorded along the crystal truncation rod of a crystal surface. In a proof-of-concept experiment on a Pt (111) sample, we present ptychographic reconstructions showing features consistent with surface steps. Due to the penetration power of x-rays, this method could find interesting applications for the study of surface structures under buried interfaces or in harsh environments.

  13. Robust Imaging Methodology for Challenging Environments: Wave Equation Dispersion Inversion of Surface Waves

    KAUST Repository

    Li, Jing; Schuster, Gerard T.; Zeng, Zhaofa

    2017-01-01

    A robust imaging technology is reviewed that provide subsurface information in challenging environments: wave-equation dispersion inversion (WD) of surface waves for the shear velocity model. We demonstrate the benefits and liabilities of the method

  14. Microbial biofilm detection on food contact surfaces by macro-scale fluorescence imaging

    Science.gov (United States)

    Hyperspectral fluorescence imaging methods were utilized to evaluate the potential of multispectral fluorescence methods for detection of pathogenic biofilm formations on four types of food contact surface materials: stainless steel, high density polyethylene (HDPE) commonly used for cutting boards,...

  15. Ptychographic x-ray imaging of surfaces on crystal truncation rod

    International Nuclear Information System (INIS)

    Zhu, Chenhui; Barbour, Andi; Liu, Yaohua; You, Hoydoo; Harder, Ross; Xu, Ruqing; Diaz, Ana; Menzel, Andreas; Komanicky, Vladimir; Huang, Xiaojing; Pierce, Michael S.

    2015-01-01

    Ptychography is a high-resolution imaging technique, which does not require lenses for image magnification and which provides phase contrast with high sensitivity. Here, we propose to use x-ray ptychography for the imaging of surface structure in crystalline samples. We show that ptychography can be used to image atomic step structures using coherent diffraction patterns recorded along the crystal truncation rod of a crystal surface. In a proof-of-concept experiment on a Pt (111) sample, we present ptychographic reconstructions showing features consistent with surface steps. Due to the penetration power of x-rays, this method could find interesting applications for the study of surface structures under buried interfaces or in harsh environments

  16. Segmentation, surface rendering, and surface simplification of 3-D skull images for the repair of a large skull defect

    Science.gov (United States)

    Wan, Weibing; Shi, Pengfei; Li, Shuguang

    2009-10-01

    Given the potential demonstrated by research into bone-tissue engineering, the use of medical image data for the rapid prototyping (RP) of scaffolds is a subject worthy of research. Computer-aided design and manufacture and medical imaging have created new possibilities for RP. Accurate and efficient design and fabrication of anatomic models is critical to these applications. We explore the application of RP computational methods to the repair of a pediatric skull defect. The focus of this study is the segmentation of the defect region seen in computerized tomography (CT) slice images of this patient's skull and the three-dimensional (3-D) surface rendering of the patient's CT-scan data. We see if our segmentation and surface rendering software can improve the generation of an implant model to fill a skull defect.

  17. STEREOLOGICAL ESTIMATION OF SURFACE AREA FROM DIGITAL IMAGES

    Directory of Open Access Journals (Sweden)

    Johanna Ziegel

    2011-05-01

    Full Text Available A sampling design of local stereology is combined with a method from digital stereology to yield a novel estimator of surface area based on counts of configurations observed in a digitization of an isotropic 2- dimensional slice with thickness s. As a tool, a result of the second author and J. Rataj on infinitesimal increase of volumes of morphological transforms is refined and used. The proposed surface area estimator is asymptotically unbiased in the case of sets contained in the ball centred at the origin with radius s and in the case of balls centred at the origin with unknown radius. For general shapes bounds for the asymptotic expected relative worst case error are given. A simulation example is discussed for surface area estimation based on 2×2×2-configurations.

  18. A mobile laboratory for surface and subsurface imaging in geo-hazard monitoring activity

    Science.gov (United States)

    Cornacchia, Carmela; Bavusi, Massimo; Loperte, Antonio; Pergola, Nicola; Pignatti, Stefano; Ponzo, Felice; Lapenna, Vincenzo

    2010-05-01

    A new research infrastructure for supporting ground-based remote sensing observations in the different phases of georisk management cycle is presented. This instrumental facility has been designed and realised by TeRN, a public-private consortium on Earth Observations and Natural Risks, in the frame of the project "ImpresAmbiente" funded by Italian Ministry of Research and University. The new infrastructure is equipped with ground-based sensors (hyperspectral cameras, thermal cameras, laser scanning and electromagnetic antennae) able to remotely map physical parameters and/or earth-surface properties (temperature, soil moisture, land cover, etc…) and to illuminate near-surface geological structures (fault, groundwater tables, landslide bodies etc...). Furthermore, the system can be used for non-invasive investigations of architectonic buildings and civil infrastructures (bridges, tunnel, road pavements, etc...) interested by natural and man-made hazards. The hyperspectral cameras can acquire high resolution images of earth-surface and cultural objects. They are operating in the Visible Near InfraRed (0.4÷1.0μm) with 1600 spatial pixel and 3.7nm of spectral sampling and in the Short Wave InfraRed (1.3÷2.5µm) spectral region with 320 spatial pixel and 5nm of spectral sampling. The IR cameras are operating in the Medium Wavelength InfraRed (3÷5µm; 640x512; NETDcultural heritage. As a consequence, laser data can be useful integrated with traditional monitoring techniques. The Laser Scanner is characterized by very high data acquisition repetition rate up to 500.000 pxl/sec with a range resolution of 0.1 mm, vertical and horizontal FoV of 310° and 360° respectively with a resolution of 0.0018°. The system is also equipped with a metric camera allows to georeference the high resolution images acquired. The electromagnetic sensors allow to obtain in near real time high-resolution 2D and 3D subsurface tomographic images. The main components are a fully automatic

  19. Determination of forest road surface roughness by Kinect depth imaging

    Directory of Open Access Journals (Sweden)

    Francesco Marinello

    2017-12-01

    Full Text Available Roughness is a dynamic property of the gravel road surface that affects safety, ride comfort as well as vehicle tyre life and maintenance costs. A rapid survey of gravel road condition is fundamental for an effective maintenance planning and definition of the intervention priorities.Different non-contact techniques such as laser scanning, ultrasonic sensors and photogrammetry have recently been proposed to reconstruct three-dimensional topography of road surface and allow extraction of roughness metrics. The application of Microsoft Kinect™ depth camera is proposed and discussed here for collection of 3D data sets from gravel roads, to be implemented in order to allow quantification of surface roughness.The objectives are to: i verify the applicability of the Kinect sensor for characterization of different forest roads, ii identify the appropriateness and potential of different roughness parameters and iii analyse the correlation with vibrations recoded by 3-axis accelerometers installed on different vehicles. The test took advantage of the implementation of the Kinect depth camera for surface roughness determination of 4 different forest gravel roads and one well-maintained asphalt road as reference. Different vehicles (mountain bike, off-road motorcycle, ATV vehicle, 4WD car and compact crossover were included in the experiment in order to verify the vibration intensity when travelling on different road surface conditions. Correlations between the extracted roughness parameters and vibration levels of the tested vehicles were then verified. Coefficients of determination of between 0.76 and 0.97 were detected between average surface roughness and standard deviation of relative accelerations, with higher values in the case of lighter vehicles.

  20. Stereological estimation of surface area from digital images

    DEFF Research Database (Denmark)

    Ziegel, Johanna; Kiderlen, Markus

    2010-01-01

    A sampling design of local stereology is combined with a method from digital stereology to yield a novel estimator of surface area based on counts of configurations observed in a digitization of an isotropic 2- dimensional slice with thickness s. As a tool, a result of the second author and J....... Rataj on infinitesimal increase of volumes of morphological transforms is refined and used. The proposed surface area estimator is asymptotically unbiased in the case of sets contained in the ball centred at the origin with radius s and in the case of balls centred at the origin with unknown radius...

  1. AFM imaging of bacteria in liquid media immobilized on gelatin coated mica surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, M.J.; Sullivan, C.J.; Hoyt, P.R.; Pelletier, D.A.; Wu, S.; Allison, D.P

    2003-10-15

    Immobilization of particulates, especially biomolecules and cells, onto surfaces is critical for imaging with the atomic force microscope (AFM). In this paper, gelatin coated mica surfaces are shown to be suitable for immobilizing and imaging both gram positive, Staphylococcus aureus, and gram negative, Escherichia coli, bacteria in both air and liquid environments. Gelatin coated surfaces are shown to be superior to poly-L-lysine coated surfaces that are commonly used for the immobilization of cells. This cell immobilization technique is being developed primarily for live cell imaging of Rhodopseudomonas palustris. The genome of R. palustris has been sequenced and the organism is the target of intensive studies aimed at understanding genome function. Images of R. palustris grown both aerobically and anaerobically in liquid media are presented. Images in liquid media show the bacteria is rod shaped and smooth while images in air show marked irregularity and folding of the surface. Significant differences in the vertical dimension are also apparent with the height of the bacteria in liquid being substantially greater than images taken in air. In air immobilized bacterial flagella are clearly seen while in liquid this structure is not visible. Additionally, significant morphological differences are observed that depend on the method of bacterial growth.

  2. Decoding using back-project algorithm from coded image in ICF

    International Nuclear Information System (INIS)

    Jiang shaoen; Liu Zhongli; Zheng Zhijian; Tang Daoyuan

    1999-01-01

    The principle of the coded imaging and its decoding in inertial confinement fusion is described simply. The authors take ring aperture microscope for example and use back-project (BP) algorithm to decode the coded image. The decoding program has been performed for numerical simulation. Simulations of two models are made, and the results show that the accuracy of BP algorithm is high and effect of reconstruction is good. Thus, it indicates that BP algorithm is applicable to decoding for coded image in ICF experiments

  3. 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.

  4. Surface interpolation with radial basis functions for medical imaging

    International Nuclear Information System (INIS)

    Carr, J.C.; Beatson, R.K.; Fright, W.R.

    1997-01-01

    Radial basis functions are presented as a practical solution to the problem of interpolating incomplete surfaces derived from three-dimensional (3-D) medical graphics. The specific application considered is the design of cranial implants for the repair of defects, usually holes, in the skull. Radial basis functions impose few restrictions on the geometry of the interpolation centers and are suited to problems where interpolation centers do not form a regular grid. However, their high computational requirements have previously limited their use to problems where the number of interpolation centers is small (<300). Recently developed fast evaluation techniques have overcome these limitations and made radial basis interpolation a practical approach for larger data sets. In this paper radial basis functions are fitted to depth-maps of the skull's surface, obtained from X-ray computed tomography (CT) data using ray-tracing techniques. They are used to smoothly interpolate the surface of the skull across defect regions. The resulting mathematical description of the skull's surface can be evaluated at any desired resolution to be rendered on a graphics workstation or to generate instructions for operating a computer numerically controlled (CNC) mill

  5. Spectrally enhanced imaging of occlusal surfaces and artificial shallow enamel erosions with a scanning fiber endoscope

    Science.gov (United States)

    Zhang, Liang; Nelson, Leonard Y.; Seibel, Eric J.

    2012-07-01

    An ultrathin scanning fiber endoscope, originally developed for cancer diagnosis, was used to image dental occlusal surfaces as well as shallow artificially induced enamel erosions from human extracted teeth (n=40). Enhanced image resolution of occlusal surfaces was obtained using a short-wavelength 405-nm illumination laser. In addition, artificial erosions of varying depths were also imaged with 405-, 404-, 532-, and 635-nm illumination lasers. Laser-induced autofluorescence images of the teeth using 405-nm illumination were also obtained. Contrast between sound and eroded enamel was quantitatively computed for each imaging modality. For shallow erosions, the image contrast with respect to sound enamel was greatest for the 405-nm reflected image. It was also determined that the increased contrast was in large part due to volume scattering with a smaller component from surface scattering. Furthermore, images obtained with a shallow penetration depth illumination laser (405 nm) provided the greatest detail of surface enamel topography since the reflected light does not contain contributions from light reflected from greater depths within the enamel tissue. Multilayered Monte Carlo simulations were also performed to confirm the experimental results.

  6. Real-time three-dimensional surface measurement by color encoded light projection

    International Nuclear Information System (INIS)

    Chen, S. Y.; Li, Y. F.; Guan, Q.; Xiao, G.

    2006-01-01

    Existing noncontact methods for surface measurement suffer from the disadvantages of poor reliability, low scanning speed, or high cost. The authors present a method for real-time three-dimensional data acquisition by a color-coded vision sensor composed of common components. The authors use a digital projector controlled by computer to generate desired color light patterns. The unique indexing of the light codes is a key problem and is solved in this study so that surface perception can be performed with only local pattern analysis of the neighbor color codes in a single image. Experimental examples and performance analysis are provided

  7. Dynamic PET simulator via tomographic emission projection for kinetic modeling and parametric image studies

    Energy Technology Data Exchange (ETDEWEB)

    Häggström, Ida, E-mail: haeggsti@mskcc.org [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 and Department of Radiation Sciences, Umeå University, Umeå 90187 (Sweden); Beattie, Bradley J.; Schmidtlein, C. Ross [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States)

    2016-06-15

    Purpose: To develop and evaluate a fast and simple tool called dPETSTEP (Dynamic PET Simulator of Tracers via Emission Projection), for dynamic PET simulations as an alternative to Monte Carlo (MC), useful for educational purposes and evaluation of the effects of the clinical environment, postprocessing choices, etc., on dynamic and parametric images. Methods: The tool was developed in MATLAB using both new and previously reported modules of PETSTEP (PET Simulator of Tracers via Emission Projection). Time activity curves are generated for each voxel of the input parametric image, whereby effects of imaging system blurring, counting noise, scatters, randoms, and attenuation are simulated for each frame. Each frame is then reconstructed into images according to the user specified method, settings, and corrections. Reconstructed images were compared to MC data, and simple Gaussian noised time activity curves (GAUSS). Results: dPETSTEP was 8000 times faster than MC. Dynamic images from dPETSTEP had a root mean square error that was within 4% on average of that of MC images, whereas the GAUSS images were within 11%. The average bias in dPETSTEP and MC images was the same, while GAUSS differed by 3% points. Noise profiles in dPETSTEP images conformed well to MC images, confirmed visually by scatter plot histograms, and statistically by tumor region of interest histogram comparisons that showed no significant differences (p < 0.01). Compared to GAUSS, dPETSTEP images and noise properties agreed better with MC. Conclusions: The authors have developed a fast and easy one-stop solution for simulations of dynamic PET and parametric images, and demonstrated that it generates both images and subsequent parametric images with very similar noise properties to those of MC images, in a fraction of the time. They believe dPETSTEP to be very useful for generating fast, simple, and realistic results, however since it uses simple scatter and random models it may not be suitable for

  8. Dynamic PET simulator via tomographic emission projection for kinetic modeling and parametric image studies

    International Nuclear Information System (INIS)

    Häggström, Ida; Beattie, Bradley J.; Schmidtlein, C. Ross

    2016-01-01

    Purpose: To develop and evaluate a fast and simple tool called dPETSTEP (Dynamic PET Simulator of Tracers via Emission Projection), for dynamic PET simulations as an alternative to Monte Carlo (MC), useful for educational purposes and evaluation of the effects of the clinical environment, postprocessing choices, etc., on dynamic and parametric images. Methods: The tool was developed in MATLAB using both new and previously reported modules of PETSTEP (PET Simulator of Tracers via Emission Projection). Time activity curves are generated for each voxel of the input parametric image, whereby effects of imaging system blurring, counting noise, scatters, randoms, and attenuation are simulated for each frame. Each frame is then reconstructed into images according to the user specified method, settings, and corrections. Reconstructed images were compared to MC data, and simple Gaussian noised time activity curves (GAUSS). Results: dPETSTEP was 8000 times faster than MC. Dynamic images from dPETSTEP had a root mean square error that was within 4% on average of that of MC images, whereas the GAUSS images were within 11%. The average bias in dPETSTEP and MC images was the same, while GAUSS differed by 3% points. Noise profiles in dPETSTEP images conformed well to MC images, confirmed visually by scatter plot histograms, and statistically by tumor region of interest histogram comparisons that showed no significant differences (p < 0.01). Compared to GAUSS, dPETSTEP images and noise properties agreed better with MC. Conclusions: The authors have developed a fast and easy one-stop solution for simulations of dynamic PET and parametric images, and demonstrated that it generates both images and subsequent parametric images with very similar noise properties to those of MC images, in a fraction of the time. They believe dPETSTEP to be very useful for generating fast, simple, and realistic results, however since it uses simple scatter and random models it may not be suitable for

  9. 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.

  10. Detection of pulmonary nodules at paediatric CT: maximum intensity projections and axial source images are complementary

    International Nuclear Information System (INIS)

    Kilburn-Toppin, Fleur; Arthurs, Owen J.; Tasker, Angela D.; Set, Patricia A.K.

    2013-01-01

    Maximum intensity projection (MIP) images might be useful in helping to differentiate small pulmonary nodules from adjacent vessels on thoracic multidetector CT (MDCT). The aim was to evaluate the benefits of axial MIP images over axial source images for the paediatric chest in an interobserver variability study. We included 46 children with extra-pulmonary solid organ malignancy who had undergone thoracic MDCT. Three radiologists independently read 2-mm axial and 10-mm MIP image datasets, recording the number of nodules, size and location, overall time taken and confidence. There were 83 nodules (249 total reads among three readers) in 46 children (mean age 10.4 ± 4.98 years, range 0.3-15.9 years; 24 boys). Consensus read was used as the reference standard. Overall, three readers recorded significantly more nodules on MIP images (228 vs. 174; P < 0.05), improving sensitivity from 67% to 77.5% (P < 0.05) but with lower positive predictive value (96% vs. 85%, P < 0.005). MIP images took significantly less time to read (71.6 ± 43.7 s vs. 92.9 ± 48.7 s; P < 0.005) but did not improve confidence levels. Using 10-mm axial MIP images for nodule detection in the paediatric chest enhances diagnostic performance, improving sensitivity and reducing reading time when compared with conventional axial thin-slice images. Axial MIP and axial source images are complementary in thoracic nodule detection. (orig.)

  11. Motion nature projection reduces patient's psycho-physiological anxiety during CT imaging.

    NARCIS (Netherlands)

    Zijlstra, Emma; Hagedoorn, Mariët; Krijnen, Wim; van der Schans, Cees; Mobach, Mark P.

    2017-01-01

    A growing body of evidence indicates that natural environments can positively influence people. This study investigated whether the use of motion nature projection in computed tomography (CT) imaging rooms is effective in mitigating psycho-physiological anxiety (vs. no intervention) using a

  12. Imaging of surface plasmon polariton interference using phase-sensitive scanning tunneling microscope

    NARCIS (Netherlands)

    Jose, J.; Segerink, Franciscus B.; Korterik, Jeroen P.; Herek, Jennifer Lynn; Offerhaus, Herman L.

    2011-01-01

    We report the surface plasmon polariton interference, generated via a ‘buried’ gold grating, and imaged using a phase-sensitive Photon Scanning Tunneling Microscope (PSTM). The phase-resolved PSTM measurement unravels the complex surface plasmon polariton interference fields at the gold-air

  13. The monocular visual imaging technology model applied in the airport surface surveillance

    Science.gov (United States)

    Qin, Zhe; Wang, Jian; Huang, Chao

    2013-08-01

    At present, the civil aviation airports use the surface surveillance radar monitoring and positioning systems to monitor the aircrafts, vehicles and the other moving objects. Surface surveillance radars can cover most of the airport scenes, but because of the terminals, covered bridges and other buildings geometry, surface surveillance radar systems inevitably have some small segment blind spots. This paper presents a monocular vision imaging technology model for airport surface surveillance, achieving the perception of scenes of moving objects such as aircrafts, vehicles and personnel location. This new model provides an important complement for airport surface surveillance, which is different from the traditional surface surveillance radar techniques. Such technique not only provides clear objects activities screen for the ATC, but also provides image recognition and positioning of moving targets in this area. Thereby it can improve the work efficiency of the airport operations and avoid the conflict between the aircrafts and vehicles. This paper first introduces the monocular visual imaging technology model applied in the airport surface surveillance and then the monocular vision measurement accuracy analysis of the model. The monocular visual imaging technology model is simple, low cost, and highly efficient. It is an advanced monitoring technique which can make up blind spot area of the surface surveillance radar monitoring and positioning systems.

  14. Reconstruction of implanted marker trajectories from cone-beam CT projection images using interdimensional correlation modeling

    International Nuclear Information System (INIS)

    Chung, Hyekyun; Poulsen, Per Rugaard; Keall, Paul J.; Cho, Seungryong; Cho, Byungchul

    2016-01-01

    Purpose: Cone-beam CT (CBCT) is a widely used imaging modality for image-guided radiotherapy. Most vendors provide CBCT systems that are mounted on a linac gantry. Thus, CBCT can be used to estimate the actual 3-dimensional (3D) position of moving respiratory targets in the thoracic/abdominal region using 2D projection images. The authors have developed a method for estimating the 3D trajectory of respiratory-induced target motion from CBCT projection images using interdimensional correlation modeling. Methods: Because the superior–inferior (SI) motion of a target can be easily analyzed on projection images of a gantry-mounted CBCT system, the authors investigated the interdimensional correlation of the SI motion with left–right and anterior–posterior (AP) movements while the gantry is rotating. A simple linear model and a state-augmented model were implemented and applied to the interdimensional correlation analysis, and their performance was compared. The parameters of the interdimensional correlation models were determined by least-square estimation of the 2D error between the actual and estimated projected target position. The method was validated using 160 3D tumor trajectories from 46 thoracic/abdominal cancer patients obtained during CyberKnife treatment. The authors’ simulations assumed two application scenarios: (1) retrospective estimation for the purpose of moving tumor setup used just after volumetric matching with CBCT; and (2) on-the-fly estimation for the purpose of real-time target position estimation during gating or tracking delivery, either for full-rotation volumetric-modulated arc therapy (VMAT) in 60 s or a stationary six-field intensity-modulated radiation therapy (IMRT) with a beam delivery time of 20 s. Results: For the retrospective CBCT simulations, the mean 3D root-mean-square error (RMSE) for all 4893 trajectory segments was 0.41 mm (simple linear model) and 0.35 mm (state-augmented model). In the on-the-fly simulations, prior

  15. Reconstruction of implanted marker trajectories from cone-beam CT projection images using interdimensional correlation modeling

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyekyun [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea and Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Poulsen, Per Rugaard [Department of Oncology, Aarhus University Hospital, Nørrebrogade 44, 8000 Aarhus C (Denmark); Keall, Paul J. [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, NSW 2006 (Australia); Cho, Seungryong [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141 (Korea, Republic of); Cho, Byungchul, E-mail: cho.byungchul@gmail.com, E-mail: bcho@amc.seoul.kr [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of)

    2016-08-15

    Purpose: Cone-beam CT (CBCT) is a widely used imaging modality for image-guided radiotherapy. Most vendors provide CBCT systems that are mounted on a linac gantry. Thus, CBCT can be used to estimate the actual 3-dimensional (3D) position of moving respiratory targets in the thoracic/abdominal region using 2D projection images. The authors have developed a method for estimating the 3D trajectory of respiratory-induced target motion from CBCT projection images using interdimensional correlation modeling. Methods: Because the superior–inferior (SI) motion of a target can be easily analyzed on projection images of a gantry-mounted CBCT system, the authors investigated the interdimensional correlation of the SI motion with left–right and anterior–posterior (AP) movements while the gantry is rotating. A simple linear model and a state-augmented model were implemented and applied to the interdimensional correlation analysis, and their performance was compared. The parameters of the interdimensional correlation models were determined by least-square estimation of the 2D error between the actual and estimated projected target position. The method was validated using 160 3D tumor trajectories from 46 thoracic/abdominal cancer patients obtained during CyberKnife treatment. The authors’ simulations assumed two application scenarios: (1) retrospective estimation for the purpose of moving tumor setup used just after volumetric matching with CBCT; and (2) on-the-fly estimation for the purpose of real-time target position estimation during gating or tracking delivery, either for full-rotation volumetric-modulated arc therapy (VMAT) in 60 s or a stationary six-field intensity-modulated radiation therapy (IMRT) with a beam delivery time of 20 s. Results: For the retrospective CBCT simulations, the mean 3D root-mean-square error (RMSE) for all 4893 trajectory segments was 0.41 mm (simple linear model) and 0.35 mm (state-augmented model). In the on-the-fly simulations, prior

  16. Three-dimensional DNA image cytometry by optical projection tomographic microscopy for early cancer diagnosis.

    Science.gov (United States)

    Agarwal, Nitin; Biancardi, Alberto M; Patten, Florence W; Reeves, Anthony P; Seibel, Eric J

    2014-04-01

    Aneuploidy is typically assessed by flow cytometry (FCM) and image cytometry (ICM). We used optical projection tomographic microscopy (OPTM) for assessing cellular DNA content using absorption and fluorescence stains. OPTM combines some of the attributes of both FCM and ICM and generates isometric high-resolution three-dimensional (3-D) images of single cells. Although the depth of field of the microscope objective was in the submicron range, it was extended by scanning the objective's focal plane. The extended depth of field image is similar to a projection in a conventional x-ray computed tomography. These projections were later reconstructed using computed tomography methods to form a 3-D image. We also present an automated method for 3-D nuclear segmentation. Nuclei of chicken, trout, and triploid trout erythrocyte were used to calibrate OPTM. Ratios of integrated optical densities extracted from 50 images of each standard were compared to ratios of DNA indices from FCM. A comparison of mean square errors with thionin, hematoxylin, Feulgen, and SYTOX green was done. Feulgen technique was preferred as it showed highest stoichiometry, least variance, and preserved nuclear morphology in 3-D. The addition of this quantitative biomarker could further strengthen existing classifiers and improve early diagnosis of cancer using 3-D microscopy.

  17. 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

  18. Atmospheric Polarization Imaging with Variable Aerosols, Clouds, and Surface Albedo

    Science.gov (United States)

    2013-07-01

    values found in this region only during episodes of intense wildfire smoke. Detailed analysis of the aerosols in this smoke plume and their effect...Continuous outdoor operation of an all-sky polarization imager,” Proc. SPIE 7672 (Polarization: Measurement, Analysis , and Remote Sensing IX), 76720A-1-7, 7...Pust, “ Lunar corona in ice wave cloud,” 10th International Meeting on Light and Color in Nature, St. Mary’s College of Maryland, 16-20 June 2010. 2

  19. A rapid method for creating qualitative images indicative of thick oil emulsion on the ocean's surface from imaging spectrometer data

    Science.gov (United States)

    Kokaly, Raymond F.; Hoefen, Todd M.; Livo, K. Eric; Swayze, Gregg A.; Leifer, Ira; McCubbin, Ian B.; Eastwood, Michael L.; Green, Robert O.; Lundeen, Sarah R.; Sarture, Charles M.; Steele, Denis; Ryan, Thomas; Bradley, Eliza S.; Roberts, Dar A.; ,

    2010-01-01

    This report describes a method to create color-composite images indicative of thick oil:water emulsions on the surface of clear, deep ocean water by using normalized difference ratios derived from remotely sensed data collected by an imaging spectrometer. The spectral bands used in the normalized difference ratios are located in wavelength regions where the spectra of thick oil:water emulsions on the ocean's surface have a distinct shape compared to clear water and clouds. In contrast to quantitative analyses, which require rigorous conversion to reflectance, the method described is easily computed and can be applied rapidly to radiance data or data that have been atmospherically corrected or ground-calibrated to reflectance. Examples are shown of the method applied to Airborne Visible/Infrared Imaging Spectrometer data collected May 17 and May 19, 2010, over the oil spill from the Deepwater Horizon offshore oil drilling platform in the Gulf of Mexico.

  20. Comparison of optical design methods of freeform surfaces for imaging applications

    Science.gov (United States)

    Agócs, Tibor

    2015-09-01

    Optical systems based on freeform optical components offer many advantages over conventional systems in imaging applications, e.g. superior image quality, compact and lightweight designs. There are a few well established manufacturing method that can be used for the generation of freeform surfaces with low surface form error and low surface roughness, in the case of freeform mirrors e.g. diamond turning, nickel plating and post-polishing. Metrology is evolving rapidly, although developments are still needed in order to verify the manufactured surface with the necessary accuracy. Optical design methods of freeform surfaces are also lagging behind, many algorithms address non-imaging applications, but in the field of imaging (image-forming) only a few exists and works with various limitations. We compare the available techniques in freeform optical design for imaging and explore the advantages, disadvantages and boundary conditions of the different methods. We also intend to identify the most useful concepts and investigate how they can be embedded into commercially available optical design software.

  1. 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.

  2. Monitoring of biofilm formation on different material surfaces of medical devices using hyperspectral imaging method

    Science.gov (United States)

    Kim, Do-Hyun; Kim, Moon S.; Hwang, Jeeseong

    2012-03-01

    Contamination of the inner surface of indwelling (implanted) medical devices by microbial biofilm is a serious problem. Some microbial bacteria such as Escherichia coli form biofilms that lead to potentially lifethreatening infections. Other types of medical devices such as bronchoscopes and duodenoscopes account for the highest number of reported endoscopic infections where microbial biofilm is one of the major causes for these infections. We applied a hyperspectral imaging method to detect biofilm contamination on the surface of several common materials used for medical devices. Such materials include stainless steel, titanium, and stainless-steeltitanium alloy. Potential uses of hyperspectral imaging technique to monitor biofilm attachment to different material surfaces are discussed.

  3. Reconstruction of pseudo three-dimensional dental image from dental panoramic radiograph and tooth surface shape

    International Nuclear Information System (INIS)

    Imura, Masataka; Kuroda, Yoshihiro; Oshiro, Osamu; Kuroda, Tomohiro; Kagiyama, Yoshiyuki; Yagi, Masakazu; Takada, Kenji; Azuma, Hiroko

    2010-01-01

    Three-dimensional volume data set is useful for diagnosis in dental treatments. However, to obtain three-dimensional images of a dental arch in general dental clinics is difficult. In this paper, we propose a method to reconstruct pseudo three-dimensional dental images from a dental panoramic radiograph and a tooth surface shape which can be obtained from three dimensional shape measurement of a dental impression. The proposed method finds an appropriate curved surface on which the dental panoramic radiograph is mapped by comparing a virtual panoramic image made from a tooth surface shape to a real panoramic radiograph. The developed pseudo three-dimensional dental images give clear impression of patient's dental condition. (author)

  4. SERS imaging of cell-surface biomolecules metabolically labeled with bioorthogonal Raman reporters.

    Science.gov (United States)

    Xiao, Ming; Lin, Liang; Li, Zefan; Liu, Jie; Hong, Senlian; Li, Yaya; Zheng, Meiling; Duan, Xuanming; Chen, Xing

    2014-08-01

    Live imaging of biomolecules with high specificity and sensitivity as well as minimal perturbation is essential for studying cellular processes. Here, we report the development of a bioorthogonal surface-enhanced Raman scattering (SERS) imaging approach that exploits small Raman reporters for visualizing cell-surface biomolecules. The cells were cultured and imaged by SERS microscopy on arrays of Raman-enhancing nanoparticles coated on silicon wafers or glass slides. The Raman reporters including azides, alkynes, and carbondeuterium bonds are small in size and spectroscopically bioorthogonal (background-free). We demonstrated that various cell-surface biomolecules including proteins, glycans, and lipids were metabolically incorporated with the corresponding precursors bearing a Raman reporter and visualized by SERS microscopy. The coupling of SERS microscopy with bioorthogonal Raman reporters expands the capabilities of live-cell microscopy beyond the modalities of fluorescence and label-free imaging. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The CEOS-Land Surface Imaging Constellation Portal for GEOSS: A resource for land surface imaging system information and data access

    Science.gov (United States)

    Holm, Thomas; Gallo, Kevin P.; Bailey, Bryan

    2010-01-01

    The Committee on Earth Observation Satellites is an international group that coordinates civil space-borne observations of the Earth, and provides the space component of the Global Earth Observing System of Systems (GEOSS). The CEOS Virtual Constellations concept was implemented in an effort to engage and coordinate disparate Earth observing programs of CEOS member agencies and ultimately facilitate their contribution in supplying the space-based observations required to satisfy the requirements of the GEOSS. The CEOS initially established Study Teams for four prototype constellations that included precipitation, land surface imaging, ocean surface topography, and atmospheric composition. The basic mission of the Land Surface Imaging (LSI) Constellation [1] is to promote the efficient, effective, and comprehensive collection, distribution, and application of space-acquired image data of the global land surface, especially to meet societal needs of the global population, such as those addressed by the nine Group on Earth Observations (GEO) Societal Benefit Areas (SBAs) of agriculture, biodiversity, climate, disasters, ecosystems, energy, health, water, and weather. The LSI Constellation Portal is the result of an effort to address important goals within the LSI Constellation mission and provide resources to assist in planning for future space missions that might further contribute to meeting those goals.

  6. MALDI-MS Imaging Analysis of Fungicide Residue Distributions on Wheat Leaf Surfaces.

    Science.gov (United States)

    Annangudi, Suresh P; Myung, Kyung; Avila Adame, Cruz; Gilbert, Jeffrey R

    2015-05-05

    Improved retention and distribution of agrochemicals on plant surfaces is an important attribute in the biological activity of pesticide. Although retention of agrochemicals on plants after spray application can be quantified using traditional analytical techniques including LC or GC, the spatial distribution of agrochemicals on the plants surfaces has received little attention. Matrix assisted laser desorption/ionization (MALDI) imaging technology has been widely used to determine the distribution of proteins, peptides and metabolites in different tissue sections, but its application to environmental research has been limited. Herein, we probed the potential utility of MALDI imaging in characterizing the distribution of three commercial fungicides on wheat leaf surfaces. Using this MALDI imaging method, we were able to detect 500 ng of epoxiconazole, azoxystrobin, and pyraclostrobin applied in 1 μL drop on the leaf surfaces using MALDI-MS. Subsequent dilutions of pyraclostrobin revealed that the compound can be chemically imaged on the leaf surfaces at levels as low as 60 ng of total applied in the area of 1 μL droplet. After application of epoxiconazole, azoxystrobin, and pyraclostrobin at a field rate of 100 gai/ha in 200 L water using a track sprayer system, residues of these fungicides on the leaf surfaces were sufficiently visualized. These results suggest that MALDI imaging can be used to monitor spatial distribution of agrochemicals on leaf samples after pesticide application.

  7. 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

  8. Projected change in characteristics of near surface temperature inversions for southeast Australia

    Science.gov (United States)

    Ji, Fei; Evans, Jason Peter; Di Luca, Alejandro; Jiang, Ningbo; Olson, Roman; Fita, Lluis; Argüeso, Daniel; Chang, Lisa T.-C.; Scorgie, Yvonne; Riley, Matt

    2018-05-01

    Air pollution has significant impacts on human health. Temperature inversions, especially near surface temperature inversions, can amplify air pollution by preventing convective movements and trapping pollutants close to the ground, thus decreasing air quality and increasing health issues. This effect of temperature inversions implies that trends in their frequency, strength and duration can have important implications for air quality. In this study, we evaluate the ability of three reanalysis-driven high-resolution regional climate model (RCM) simulations to represent near surface inversions at 9 sounding sites in southeast Australia. Then we use outputs of 12 historical and future RCM simulations (each with three time periods: 1990-2009, 2020-2039, and 2060-2079) from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project to investigate changes in near surface temperature inversions. The results show that there is a substantial increase in the strength of near surface temperature inversions over southeast Australia which suggests that future inversions may intensify poor air quality events. Near surface inversions and their future changes have clear seasonal and diurnal variations. The largest differences between simulations are associated with the driving GCMs, suggesting that the large-scale circulation plays a dominant role in near surface inversion strengths.

  9. Self-consistent density functional calculation of the image potential at a metal surface

    International Nuclear Information System (INIS)

    Jung, J; Alvarellos, J E; Chacon, E; GarcIa-Gonzalez, P

    2007-01-01

    It is well known that the exchange-correlation (XC) potential at a metal surface has an image-like asymptotic behaviour given by -1/4(z-z 0 ), where z is the coordinate perpendicular to the surface. Using a suitable fully non-local functional prescription, we evaluate self-consistently the XC potential with the correct image behaviour for simple jellium surfaces in the range of metallic densities. This allows a proper comparison between the corresponding image-plane position, z 0 , and other related quantities such as the centroid of an induced charge by an external perturbation. As a by-product, we assess the routinely used local density approximation when evaluating electron density profiles, work functions, and surface energies by focusing on the XC effects included in the fully non-local description

  10. Self-consistent density functional calculation of the image potential at a metal surface

    Energy Technology Data Exchange (ETDEWEB)

    Jung, J [Departamento de Fisica Fundamental, Universidad Nacional de Educacion a Distancia, Apartado 60141, 28080 Madrid (Spain); Alvarellos, J E [Departamento de Fisica Fundamental, Universidad Nacional de Educacion a Distancia, Apartado 60141, 28080 Madrid (Spain); Chacon, E [Instituto de Ciencias de Materiales de Madrid, Consejo Superior de Investigaciones CientIficas, E-28049 Madrid (Spain); GarcIa-Gonzalez, P [Departamento de Fisica Fundamental, Universidad Nacional de Educacion a Distancia, Apartado 60141, 28080 Madrid (Spain)

    2007-07-04

    It is well known that the exchange-correlation (XC) potential at a metal surface has an image-like asymptotic behaviour given by -1/4(z-z{sub 0}), where z is the coordinate perpendicular to the surface. Using a suitable fully non-local functional prescription, we evaluate self-consistently the XC potential with the correct image behaviour for simple jellium surfaces in the range of metallic densities. This allows a proper comparison between the corresponding image-plane position, z{sub 0}, and other related quantities such as the centroid of an induced charge by an external perturbation. As a by-product, we assess the routinely used local density approximation when evaluating electron density profiles, work functions, and surface energies by focusing on the XC effects included in the fully non-local description.

  11. Spontaneous reorientation is guided by perceived surface distance, not by image matching or comparison.

    Directory of Open Access Journals (Sweden)

    Sang Ah Lee

    Full Text Available Humans and animals recover their sense of position and orientation using properties of the surface layout, but the processes underlying this ability are disputed. Although behavioral and neurophysiological experiments on animals long have suggested that reorientation depends on representations of surface distance, recent experiments on young children join experimental studies and computational models of animal navigation to suggest that reorientation depends either on processing of any continuous perceptual variables or on matching of 2D, depthless images of the landscape. We tested the surface distance hypothesis against these alternatives through studies of children, using environments whose 3D shape and 2D image properties were arranged to enhance or cancel impressions of depth. In the absence of training, children reoriented by subtle differences in perceived surface distance under conditions that challenge current models of 2D-image matching or comparison processes. We provide evidence that children's spontaneous navigation depends on representations of 3D layout geometry.

  12. Dust Plate, Retina, Photograph: Imaging on Experimental Surfaces in Early Nineteenth-Century Physics.

    Science.gov (United States)

    Ramalingam, Chitra

    2015-09-01

    This article explores the entangled histories of three imaging techniques in early nineteenth-century British physical science, techniques in which a dynamic event (such as a sound vibration or an electric spark) was made to leave behind a fixed trace on a sensitive surface. Three categories of "sensitive surface" are examined in turn: first, a metal plate covered in fine dust; second, the retina of the human eye; and finally, a surface covered with a light-sensitive chemical emulsion (a photographic plate). For physicists Michael Faraday and Charles Wheatstone, and photographic pioneer William Henry Fox Talbot, transient phenomena could be studied through careful observation and manipulation of the patterns wrought on these different surfaces, and through an understanding of how the imaging process unfolded through time. This exposes the often-ignored materiality and temporality of epistemic practices around nineteenth-century scientific images said to be "drawn by nature."

  13. Fusion of MODIS and landsat-8 surface temperature images: a new approach.

    Science.gov (United States)

    Hazaymeh, Khaled; Hassan, Quazi K

    2015-01-01

    Here, our objective was to develop a spatio-temporal image fusion model (STI-FM) for enhancing temporal resolution of Landsat-8 land surface temperature (LST) images by fusing LST images acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS); and implement the developed algorithm over a heterogeneous semi-arid study area in Jordan, Middle East. The STI-FM technique consisted of two major components: (i) establishing a linear relationship between two consecutive MODIS 8-day composite LST images acquired at time 1 and time 2; and (ii) utilizing the above mentioned relationship as a function of a Landsat-8 LST image acquired at time 1 in order to predict a synthetic Landsat-8 LST image at time 2. It revealed that strong linear relationships (i.e., r2, slopes, and intercepts were in the range 0.93-0.94, 0.94-0.99; and 2.97-20.07) existed between the two consecutive MODIS LST images. We evaluated the synthetic LST images qualitatively and found high visual agreements with the actual Landsat-8 LST images. In addition, we conducted quantitative evaluations of these synthetic images; and found strong agreements with the actual Landsat-8 LST images. For example, r2, root mean square error (RMSE), and absolute average difference (AAD)-values were in the ranges 084-0.90, 0.061-0.080, and 0.003-0.004, respectively.

  14. Multi-mission mean sea surface and geoid models for ocean monitoring within the GOCINA project

    Science.gov (United States)

    Andersen, O. B.; Knudsen, P.; Anne, V. L.

    2004-05-01

    A major goal of the EU project GOCINA (Geoid and Ocean Circulation In the North Atlantic) is to develop tools for ocean monitoring using satellite altimetry combined with satellite gravimetry. Furthermore, the project will determine an accurate geoid in the region between Greenland and the UK and, hereby, create a platform for validation of future GOCE Level 2 data and higher order scientific products. The central quantity bridging the geoid and the ocean circulation is the mean dynamic topography, which is the difference between the mean sea surface and the geoid. The mean dynamic topography provides the absolute reference surface for the ocean circulation. The improved determination of the mean circulation will advance the understanding of the role of the ocean mass and heat transport in climate change. To calculate the best possible synthetic mean dynamic topographies a new mean sea surface (KMS03) has been derived from nine years of altimetric data (1993-2001). The regional geoid has furthermore being updated using GRACE and gravimetric data from a recent airborne survey. New synthetic mean dynamic topography models have been computed from the best available geoid models (EGM96, GRACE, GOCINA) and the present mean sea surface models (i.e. CLS01, GSFC00, KMS03). These models will be compared with state of the art hydrodynamic mean dynamic topography models in the North Atlantic GOCINA area. An extended comparison in the Artic Ocean will also be presented to demonstrate the impact of improved geoid and mean sea surface modeling. Particularly using the GRACE derived geoid models, and the KMS03 mean sea surface.

  15. 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.

  16. Minimizing image noise in on-board CT reconstruction using both kilovoltage and megavoltage beam projections

    International Nuclear Information System (INIS)

    Zhang Junan; Yin Fangfang

    2007-01-01

    We studied a recently proposed aggregated CT reconstruction technique which combines the complementary advantages of kilovoltage (kV) and megavoltage (MV) x-ray imaging. Various phantoms were imaged to study the effects of beam orientations and geometry of the imaging object on image quality of reconstructed CT. It was shown that the quality of aggregated CT was correlated with both kV and MV beam orientations and the degree of this correlation depended upon the geometry of the imaging object. The results indicated that the optimal orientations were those when kV beams pass through the thinner portion and MV beams pass through the thicker portion of the imaging object. A special preprocessing procedure was also developed to perform contrast conversions between kV and MV information prior to image reconstruction. The performance of two reconstruction methods, one filtered backprojection method and one iterative method, were compared. The effects of projection number, beam truncation, and contrast conversion on the CT image quality were investigated

  17. 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.

  18. Nanoscale imaging of surface piezoresponse on GaN epitaxial layers

    International Nuclear Information System (INIS)

    Stoica, T.; Calarco, R.; Meijers, R.; Lueth, H.

    2007-01-01

    Surfaces of GaN films were investigated by atomic force microscopy (AFM) with implemented piezoelectric force microscopy technique. A model of PFM based on the surface depletion region in GaN films is discussed. The local piezoelectric effect of the low frequency regime was found to be in phase with the applied voltage on large domains, corresponding to a Ga-face of the GaN layer. Low piezoresponse is obtained within the inter-domain regions. The use of frequencies near a resonance frequency enhances very much the resolution of piezo-imaging, but only for very low scanning speed the piezo-imaging can follow the local piezoelectric effect. An inversion of the PFM image contrast is obtained for frequencies higher than the resonance frequencies. The effect of a chemical surface treatment on the topography and the piezoresponse of the GaN films was also investigated. Textured surfaces with very small domains were observed after the chemical treatment. For this kind of surfaces, piezo-induced torsion rather than bending of the AFM cantilever dominates the contrast of the PFM images. A small memory effect was observed, and explained by surface charging and confinement of the piezoelectric effect within the carrier depletion region at the GaN surface

  19. 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

  20. Atomic imaging of an InSe single-crystal surface with atomic force microscope

    OpenAIRE

    Uosaki, Kohei; Koinuma, Michio

    1993-01-01

    The atomic force microscope was employed to observed in air the surface atomic structure of InSe, one of III-VI compound semiconductors with layered structures. Atomic arrangements were observed in both n-type and p-type materials. The observed structures are in good agreement with those expected from bulk crystal structures. The atomic images became less clear by repeating the imaging process. Wide area imaging after the imaging of small area clearly showed that a mound was created at the sp...

  1. 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.

  2. Mizunami Underground Research Laboratory project. A project on research stage of investigating prediction from ground surface. Project report at fiscal year of 2000 to 2004

    International Nuclear Information System (INIS)

    2000-04-01

    This was a detailed plan after fiscal year 2000 on the first stage of the Research stage at investigating prediction from ground surface' in three researches carried out at the Mizunami Underground Research Laboratory (MIU) according to the 'Basic plan on research of underground science at MIU', based on progress of investigation and research before fiscal year 1999. This project contains following three items as its general targets; establishment of general investigating techniques for geological environment, collection of informations on deep underground environment, and development on foundation of engineering technology at super-deep underground. And, targets at investigating prediction stage from ground surface contain acquisition of geological environment data through investigations from ground surface to predict changes of the environment accompanied with underground geological environment and construction of experimental tunnel, to determine evaluating method on prediction results, and to determine plannings of an investigating stage accompanied with excavation of the tunnel by carrying out detail design of the tunnel. Here were introduced about results and problems on the investigation of the first phase, the integration of investigating results, and the investigation and researches on geology/geological structure, hydrology and geochemistry of groundwater, mechanical properties of rocks, and the mass transfer. (G.K.)

  3. Projections of rapidly rising surface temperatures over Africa under low mitigation

    International Nuclear Information System (INIS)

    Engelbrecht, Francois; Bopape, Mary-Jane; Naidoo, Mogesh; Garland, Rebecca; Adegoke, Jimmy; Thatcher, Marcus; McGregor, John; Katzfey, Jack; Werner, Micha; Ichoku, Charles; Gatebe, Charles

    2015-01-01

    An analysis of observed trends in African annual-average near-surface temperatures over the last five decades reveals drastic increases, particularly over parts of the subtropics and central tropical Africa. Over these regions, temperatures have been rising at more than twice the global rate of temperature increase. An ensemble of high-resolution downscalings, obtained using a single regional climate model forced with the sea-surface temperatures and sea-ice fields of an ensemble of global circulation model (GCM) simulations, is shown to realistically represent the relatively strong temperature increases observed in subtropical southern and northern Africa. The amplitudes of warming are generally underestimated, however. Further warming is projected to occur during the 21st century, with plausible increases of 4–6 °C over the subtropics and 3–5 °C over the tropics by the end of the century relative to present-day climate under the A2 (a low mitigation) scenario of the Special Report on Emission Scenarios. High impact climate events such as heat-wave days and high fire-danger days are consistently projected to increase drastically in their frequency of occurrence. General decreases in soil-moisture availability are projected, even for regions where increases in rainfall are plausible, due to enhanced levels of evaporation. The regional dowscalings presented here, and recent GCM projections obtained for Africa, indicate that African annual-averaged temperatures may plausibly rise at about 1.5 times the global rate of temperature increase in the subtropics, and at a somewhat lower rate in the tropics. These projected increases although drastic, may be conservative given the model underestimations of observed temperature trends. The relatively strong rate of warming over Africa, in combination with the associated increases in extreme temperature events, may be key factors to consider when interpreting the suitability of global mitigation targets in terms of

  4. Surface Activity Distributions of Comet 67P/Churyumov-Gerasimenko Derived from VIRTIS Images

    Science.gov (United States)

    Fougere, Nicolas; Combi, Michael R.; Tenishev, Valeriy; Migliorini, Alessandra; Bockelee-Morvan, Dominique; Fink, Uwe; Filacchione, Gianrico; Rinaldi, Giovanna; Capaccioni, Fabrizio; Toth, Gabor; Gombosi, T. I.; Hansen, Kenneth C.; Huang, Zhenguang; Shou, Yinsi; VIRTIS Team

    2017-10-01

    The outgassing mechanism of comets still remains a critical question to better understand these objects. The Rosetta mission gave some insight regarding the potential activity distribution from the surface of the nucleus of comet 67P/Churyumov-Gerasimenko, Fougere et al. (2016, Astronomy & Astrophysics, Volume 588, id.A134, 11 pp and Monthly Notices of the Royal Astronomical Society, Volume 462, Issue Suppl_1, p.S156-S169) used a spherical harmonics inversion scheme with in-situ measurements from the ROSINA instrument to derive mapping of the broad distribution of potential activity at the surface of the nucleus. Marschall et al. (2016, Astronomy & Astrophysics, doi: 10.1051/0004-6361/201730849) based on the appearance of dust active areas suggested that the so-called “neck” region and regions with fractured cliffs and locally steep slopes show more activity than the rest of comet 67P’s nucleus. Using in situ ROSINA measurements from a distance makes it difficult to distinguish between these two scenarios because the fast expansion of the gas and large molecular mean free paths prevents distinguishing small outgassing features even when the spacecraft was in bound orbits within 10 km from the nucleus. In this paper, we present a similar numerical inversion approach using VIRTIS images, which should better probe the very inner coma of comet 67P and give more detailed information about the outgassing activity. Support from contracts JPL #1266314 and #1266313 from the US Rosetta Project and grant NNX14AG84G from the NASA Planetary Atmospheres Program are gratefully acknowledged.

  5. Clinical usefulness of a newly-developed head and neck surface coil for MR imaging

    International Nuclear Information System (INIS)

    Shimada, Morio; Kogure, Takashi; Hayashi, Sanshin

    1995-01-01

    To obtain correct diagnosis at early stages of cervical lymph node swelling, especially cases with suspected epipharyngeal carcinoma, and cerebral arterial sclerotic diseases, high-quality MR images visualizing the entire head and neck structures and vessels are of crucial importance. When obtaining images of head and neck regions using a head coil, signal intensity (SI) and signal to noise ratio (SNR) of regions below the hypopharynx are weakened. Moreover, when obtaining images of head and neck regions using an anterior neck coil, SI and SNR of upper regions of epipharynx are also weakened. In an attempt to solve these problems, we developed a new head and neck surface coil for MR imaging. With this new coil we were able to obtain better images (153 cases) from regions below the hypopharynx to the upper regions of the epipharynx in the same time as images obtained using the head coil and anterior neck coil. 2D TOF MR angiographic images (11 cases) obtained by the head and neck surface coil are superior to 2D TOF angiographic images obtained by the anterior neck coil. MR images obtained with this improved method are valuable in the evaluation and management of head and neck region disease. (author)

  6. 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)

  7. 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)

  8. 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.

  9. Surface nuclear magnetic resonance imaging of water content distribution in the subsurface. 1998 annual progress report

    International Nuclear Information System (INIS)

    Hendrickx, J.M.H.

    1998-01-01

    'The objective of the project is to evaluate Surface Nuclear Magnetic Resonance Imaging ( NMRI) for determining water content distribution in the subsurface. In NMRI the interaction of the magnetic moment of hydrogen ( protons) nuclei with external applied electromagnetic ( EM ) fields is measured. In surface NMRI the Earth''s magnetic field causes alignment of the spinning protons. An alternating EM field is generated by a loop of wire laid on the Earth surface. The alternating current driven through the loop at the Lamor frequency of protons in liquid water. The component of the EM field perpendicular to the Earth''s field causes a precession of protons from their equilibrium position. Water content distribution in the subsurface is derived from measurements on the EM field caused by the return of the precessing protons to equilibrium after the current in the transmitter loop is terminated. The scientific goals of the R and D are: to verify and validate the theoretical concepts and experimental results of Russian scientists, who first introduced this method; to evaluate the range of applications and limitations of this technology for practical field measurements. NMRI has the potential of providing a remote, direct, unique method for subsurface water measurements. All present methods are either intrusive or indirect ( e.g. electrical resitivity measurements). In the past year progress has been made along two separate paths. These are: (1) Field Measurements. Surface NMRI equipment manufactured by IRIS Instruments of France was tested over a number of sites with good hydrogeologic control. The results of these measurements can be summarized as follows: The NMRI measurement directly and uniquely determines water distribution in coarse grained aquifers; geologic formation from which water can be readily withdrawn. Water content can not be determined by this technique in fine grained sediments. The signal to be measured is very small and EM interference''s from power

  10. Establishment of the method of surface shaded display for brain PET imaging

    International Nuclear Information System (INIS)

    Zhang Xiangsong; Tang Anwu; He Zuoxiang

    2003-01-01

    Objective: To establish the method of surface shaded display (SSD) for brain PET imaging. Methods: The original brain PET images volume data were transferred to the personal computer by the local area network, and scaled into 256 grayscale values between 0 and 255. An appropriate threshold could be selected with three differential methods: depended on the histogram or maximum percentage of the volume data and the opposite value percentage of the lesion. The list of vertices and triangles describing the contour surface was produced with a high resolution three dimensional (3D) surface construction algorithm. Results: The final software of SSD for brain PET imaging with interactive user interface can produce 3D brain PET images which can be rotated, scaled, and saved or outputted with several image formats. Conclusion: The method of SSD for brain PET imaging can directly and integrally reflect the surface of brain cortex, and be helpful to locate lesions and display the range of lesions, but can not reflect the severity of lesions, nor can display the structure under brain cortex

  11. Approximation by Cylinder Surfaces

    DEFF Research Database (Denmark)

    Randrup, Thomas

    1997-01-01

    We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

  12. Comparison of surface coil and knee coil for evaluation of the patellar cartilage by MR imaging

    International Nuclear Information System (INIS)

    Steen, M. van den; Maeseneer, M. de; Hoste, M.; Vanderdood, K.; Ridder, F. de; Osteaux, M.

    2003-01-01

    Purpose: The aim of this work was to compare the knee coil and the surface coil for the visualisation of the patellar cartilage. Materials and methods: In 28 patients (17 women, 11 men) with an average age of 40 years (range 14-76) with knee pain MR was performed. Transverse images were obtained using a fast spin echo proton density weighted sequence on a Philips Gyroscan Intera 1.5 T clinical system. Transverse images were obtained at the level of the patellar cartilage using both the surface and the knee coil. All images were evaluated by consensus of two radiologists. They evaluated a number of quality criteria on a 4-point scale. Criteria for artefacts were also graded on a 4-point scale. Results: For the visualisation of fluid there was no significant difference between the knee coil and the surface coil (P=0.021). For all other criteria regarding image quality and presence of imaging artefacts there was a significant difference between both coils (P<0.001) with the surface coil obtaining the better result. Conclusion: The use of the surface coil in the visualisation of the patellar cartilage can be recommended at knee MR

  13. Multi circular-cavity surface coil for magnetic resonance imaging of monkey's brain at 4 Tesla

    Science.gov (United States)

    Osorio, A. I.; Solis-Najera, S. E.; Vázquez, F.; Wang, R. L.; Tomasi, D.; Rodriguez, A. O.

    2014-11-01

    Animal models in medical research has been used to study humans diseases for several decades. The use of different imaging techniques together with different animal models offers a great advantage due to the possibility to study some human pathologies without the necessity of chirurgical intervention. The employ of magnetic resonance imaging for the acquisition of anatomical and functional images is an excellent tool because its noninvasive nature. Dedicated coils to perform magnetic resonance imaging experiments are obligatory due to the improvement on the signal-to-noise ratio and reduced specific absorption ratio. A specifically designed surface coil for magnetic resonance imaging of monkey's brain is proposed based on the multi circular-slot coil. Numerical simulations of the magnetic and electric fields were also performed using the Finite Integration Method to solve Maxwell's equations for this particular coil design and, to study the behavior of various vector magnetic field configurations and specific absorption ratio. Monkey's brain images were then acquired with a research-dedicated magnetic resonance imaging system at 4T, to evaluate the anatomical images with conventional imaging sequences. This coil showed good quality images of a monkey's brain and full compatibility with standard pulse sequences implemented in research-dedicated imager.

  14. Quantitative sub-surface and non-contact imaging using scanning microwave microscopy

    International Nuclear Information System (INIS)

    Gramse, Georg; Kasper, Manuel; Hinterdorfer, Peter; Brinciotti, Enrico; Rankl, Christian; Kienberger, Ferry; Lucibello, Andrea; Marcelli, Romolo; Patil, Samadhan B.; Giridharagopal, Rajiv

    2015-01-01

    The capability of scanning microwave microscopy for calibrated sub-surface and non-contact capacitance imaging of silicon (Si) samples is quantitatively studied at broadband frequencies ranging from 1 to 20 GHz. Calibrated capacitance images of flat Si test samples with varying dopant density (10 15 –10 19 atoms cm −3 ) and covered with dielectric thin films of SiO 2 (100–400 nm thickness) are measured to demonstrate the sensitivity of scanning microwave microscopy (SMM) for sub-surface imaging. Using standard SMM imaging conditions the dopant areas could still be sensed under a 400 nm thick oxide layer. Non-contact SMM imaging in lift-mode and constant height mode is quantitatively demonstrated on a 50 nm thick SiO 2 test pad. The differences between non-contact and contact mode capacitances are studied with respect to the main parameters influencing the imaging contrast, namely the probe tip diameter and the tip–sample distance. Finite element modelling was used to further analyse the influence of the tip radius and the tip–sample distance on the SMM sensitivity. The understanding of how the two key parameters determine the SMM sensitivity and quantitative capacitances represents an important step towards its routine application for non-contact and sub-surface imaging. (paper)

  15. 3D craniofacial registration using thin-plate spline transform and cylindrical surface projection.

    Science.gov (United States)

    Chen, Yucong; Zhao, Junli; Deng, Qingqiong; Duan, Fuqing

    2017-01-01

    Craniofacial registration is used to establish the point-to-point correspondence in a unified coordinate system among human craniofacial models. It is the foundation of craniofacial reconstruction and other craniofacial statistical analysis research. In this paper, a non-rigid 3D craniofacial registration method using thin-plate spline transform and cylindrical surface projection is proposed. First, the gradient descent optimization is utilized to improve a cylindrical surface fitting (CSF) for the reference craniofacial model. Second, the thin-plate spline transform (TPST) is applied to deform a target craniofacial model to the reference model. Finally, the cylindrical surface projection (CSP) is used to derive the point correspondence between the reference and deformed target models. To accelerate the procedure, the iterative closest point ICP algorithm is used to obtain a rough correspondence, which can provide a possible intersection area of the CSP. Finally, the inverse TPST is used to map the obtained corresponding points from the deformed target craniofacial model to the original model, and it can be realized directly by the correspondence between the original target model and the deformed target model. Three types of registration, namely, reflexive, involutive and transitive registration, are carried out to verify the effectiveness of the proposed craniofacial registration algorithm. Comparison with the methods in the literature shows that the proposed method is more accurate.

  16. 3D craniofacial registration using thin-plate spline transform and cylindrical surface projection.

    Directory of Open Access Journals (Sweden)

    Yucong Chen

    Full Text Available Craniofacial registration is used to establish the point-to-point correspondence in a unified coordinate system among human craniofacial models. It is the foundation of craniofacial reconstruction and other craniofacial statistical analysis research. In this paper, a non-rigid 3D craniofacial registration method using thin-plate spline transform and cylindrical surface projection is proposed. First, the gradient descent optimization is utilized to improve a cylindrical surface fitting (CSF for the reference craniofacial model. Second, the thin-plate spline transform (TPST is applied to deform a target craniofacial model to the reference model. Finally, the cylindrical surface projection (CSP is used to derive the point correspondence between the reference and deformed target models. To accelerate the procedure, the iterative closest point ICP algorithm is used to obtain a rough correspondence, which can provide a possible intersection area of the CSP. Finally, the inverse TPST is used to map the obtained corresponding points from the deformed target craniofacial model to the original model, and it can be realized directly by the correspondence between the original target model and the deformed target model. Three types of registration, namely, reflexive, involutive and transitive registration, are carried out to verify the effectiveness of the proposed craniofacial registration algorithm. Comparison with the methods in the literature shows that the proposed method is more accurate.

  17. Underwater 3D Surface Measurement Using Fringe Projection Based Scanning Devices.

    Science.gov (United States)

    Bräuer-Burchardt, Christian; Heinze, Matthias; Schmidt, Ingo; Kühmstedt, Peter; Notni, Gunther

    2015-12-23

    In this work we show the principle of optical 3D surface measurements based on the fringe projection technique for underwater applications. The challenges of underwater use of this technique are shown and discussed in comparison with the classical application. We describe an extended camera model which takes refraction effects into account as well as a proposal of an effective, low-effort calibration procedure for underwater optical stereo scanners. This calibration technique combines a classical air calibration based on the pinhole model with ray-based modeling and requires only a few underwater recordings of an object of known length and a planar surface. We demonstrate a new underwater 3D scanning device based on the fringe projection technique. It has a weight of about 10 kg and the maximal water depth for application of the scanner is 40 m. It covers an underwater measurement volume of 250 mm × 200 mm × 120 mm. The surface of the measurement objects is captured with a lateral resolution of 150 μm in a third of a second. Calibration evaluation results are presented and examples of first underwater measurements are given.

  18. Multimodal imaging of ocular surface of dry eye subjects

    Science.gov (United States)

    Zhang, Aizhong; Salahura, Gheorghe; Kottaiyan, Ranjini; Yoon, Geunyoung; Aquavella, James V.; Zavislan, James M.

    2016-03-01

    To study the relationship between the corneal lipid layer and the ocular surface temperature (OST), we conducted a clinical trial for 20 subjects. Subjects were clinically screened prior to the trial. Of the 20 subjects, 15 have Meibomian gland dysfunction (MGD), and 5 have aqueous-deficient dry eye (ADDE). A custom, circularly polarized illumination video tearscope measured the lipid layer thickness of the ocular tear film. A long-wave infrared video camera recorded the dynamic thermal properties of the ocular team film. The results of these two methods were analyzed and compared. Using principal component analysis (PCA) of the lipid layer distribution, we find that the 20 subjects could be categorized into five statistically significant groups, independent of their original clinical classification: thin (6 subjects), medium (5 subjects), medium and homogenous (3 subjects), thick (4 subjects), and very thick (2 subjects) lipids, respectively. We also conducted PCA of the OST data, and recategorized the subjects into two thermal groups by k-means clustering: one includes all ADDE subjects and some MGD subjects; the other includes the remaining MGD subjects. By comparing these two methods, we find that dry eye subjects with thin ( 40 nm), there is no strong correlation between the lipid layer thickness and heterogeneity and the OST patterns.

  19. Regional quantitative analysis of cortical surface maps of FDG PET images

    CERN Document Server

    Protas, H D; Hayashi, K M; Chin Lung, Yu; Bergsneider, M; Sung Cheng, Huang

    2006-01-01

    Cortical surface maps are advantageous for visualizing the 3D profile of cortical gray matter development and atrophy, and for integrating structural and functional images. In addition, cortical surface maps for PET data, when analyzed in conjunction with structural MRI data allow us to investigate, and correct for, partial volume effects. Here we compared quantitative regional PET values based on a 3D cortical surface modeling approach with values obtained directly from the 3D FDG PET images in various atlas-defined regions of interest (ROIs; temporal, parietal, frontal, and occipital lobes). FDG PET and 3D MR (SPGR) images were obtained and aligned to ICBM space for 15 normal subjects. Each image was further elastically warped in 2D parameter space of the cortical surface, to align major cortical sulci. For each point within a 15 mm distance of the cortex, the value of the PET intensity was averaged to give a cortical surface map of FDG uptake. The average PET values on the cortical surface map were calcula...

  20. Estimation of Shie Glacier Surface Movement Using Offset Tracking Technique with Cosmo-Skymed Images

    Science.gov (United States)

    Wang, Q.; Zhou, W.; Fan, J.; Yuan, W.; Li, H.; Sousa, J. J.; Guo, Z.

    2017-09-01

    Movement is one of the most important characteristics of glaciers which can cause serious natural disasters. For this reason, monitoring this massive blocks is a crucial task. Synthetic Aperture Radar (SAR) can operate all day in any weather conditions and the images acquired by SAR contain intensity and phase information, which are irreplaceable advantages in monitoring the surface movement of glaciers. Moreover, a variety of techniques like DInSAR and offset tracking, based on the information of SAR images, could be applied to measure the movement. Sangwang lake, a glacial lake in the Himalayas, has great potentially danger of outburst. Shie glacier is situated at the upstream of the Sangwang lake. Hence, it is significant to monitor Shie glacier surface movement to assess the risk of outburst. In this paper, 6 high resolution COSMO-SkyMed images spanning from August to December, 2016 are applied with offset tracking technique to estimate the surface movement of Shie glacier. The maximum velocity of Shie glacier surface movement is 51 cm/d, which was observed at the end of glacier tongue, and the velocity is correlated with the change of elevation. Moreover, the glacier surface movement in summer is faster than in winter and the velocity decreases as the local temperature decreases. Based on the above conclusions, the glacier may break off at the end of tongue in the near future. The movement results extracted in this paper also illustrate the advantages of high resolution SAR images in monitoring the surface movement of small glaciers.

  1. A multi-slot surface coil for MRI of dual-rat imaging at 4 T

    International Nuclear Information System (INIS)

    Solis, S E; Rodriguez, A O; Wang, R; Tomasi, D

    2011-01-01

    A slotted surface coil inspired by the hole-and-slot cavity magnetron was developed for magnetic resonance imaging of obese rats at 4 T. Full-wave analysis of the magnetic field was carried out at 170 MHz for both the slotted and circular-shaped coils. The noise figure values of two coils were investigated via the numerical calculation of the quality factors. Fat simulated phantoms to mimic overweight rats were included in the analysis with weights ranging from 300 to 900 g. The noise figures were 1.2 dB for the slotted coil and 2.4 dB for the circular coil when loaded with 600 g of simulated phantom. A slotted surface coil with eight circular slots and a circular coil with similar dimensions were built and operated in the transceiver mode, and their performances were experimentally compared. The imaging tests in phantoms demonstrated that the slotted surface coil has a deeper RF-sensitivity and better field uniformity than the single-loop RF-coil. High quality images of two overweight Zucker rats were acquired simultaneously with the slotted surface coil using standard spin-echo pulse sequences. Experimental results showed that the slotted surface coil outperformed the circular coil for imaging considerably overweight rats. Thus, the slotted surface coil can be a good tool for MRI experiments in rats on a human whole-body 4 T scanner.

  2. A multi-slot surface coil for MRI of dual-rat imaging at 4 T

    Energy Technology Data Exchange (ETDEWEB)

    Solis, S E; Rodriguez, A O [Departamento de Ingenieria Electrica, Universidad Autonoma Metropolitana Iztapalapa, Mexico, DF 09340 (Mexico); Wang, R; Tomasi, D, E-mail: arog@xanum.uam.mx [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2011-06-21

    A slotted surface coil inspired by the hole-and-slot cavity magnetron was developed for magnetic resonance imaging of obese rats at 4 T. Full-wave analysis of the magnetic field was carried out at 170 MHz for both the slotted and circular-shaped coils. The noise figure values of two coils were investigated via the numerical calculation of the quality factors. Fat simulated phantoms to mimic overweight rats were included in the analysis with weights ranging from 300 to 900 g. The noise figures were 1.2 dB for the slotted coil and 2.4 dB for the circular coil when loaded with 600 g of simulated phantom. A slotted surface coil with eight circular slots and a circular coil with similar dimensions were built and operated in the transceiver mode, and their performances were experimentally compared. The imaging tests in phantoms demonstrated that the slotted surface coil has a deeper RF-sensitivity and better field uniformity than the single-loop RF-coil. High quality images of two overweight Zucker rats were acquired simultaneously with the slotted surface coil using standard spin-echo pulse sequences. Experimental results showed that the slotted surface coil outperformed the circular coil for imaging considerably overweight rats. Thus, the slotted surface coil can be a good tool for MRI experiments in rats on a human whole-body 4 T scanner.

  3. A multi-slot surface coil for MRI of dual-rat imaging at 4T

    Energy Technology Data Exchange (ETDEWEB)

    Solis, S.E.; Tomasi, D.; Solis, S.E.; Wang, R.; Tomasi, D.; Rodriguez, A.O.

    2011-07-01

    A slotted surface coil inspired by the hole-and-slot cavity magnetron was developed for magnetic resonance imaging of obese rats at 4 T. Full-wave analysis of the magnetic field was carried out at 170 MHz for both the slotted and circular-shaped coils. The noise figure values of two coils were investigated via the numerical calculation of the quality factors. Fat simulated phantoms to mimic overweight rats were included in the analysis with weights ranging from 300 to 900 g. The noise figures were 1.2 dB for the slotted coil and 2.4 dB for the circular coil when loaded with 600 g of simulated phantom. A slotted surface coil with eight circular slots and a circular coil with similar dimensions were built and operated in the transceiver mode, and their performances were experimentally compared. The imaging tests in phantoms demonstrated that the slotted surface coil has a deeper RF-sensitivity and better field uniformity than the single-loop RF-coil. High quality images of two overweight Zucker rats were acquired simultaneously with the slotted surface coil using standard spin-echo pulse sequences. Experimental results showed that the slotted surface coil outperformed the circular coil for imaging considerably overweight rats. Thus, the slotted surface coil can be a good tool for MRI experiments in rats on a human whole-body 4 T scanner.

  4. 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

  5. Multi-detector and systematic imaging system designed and developed within the New AGLAE project

    Energy Technology Data Exchange (ETDEWEB)

    Pichon, L.; Pacheco, C.; Moignard, B.; Lemasson, Q. [C2RMF - Palais du Louvre 14 quai F Mitterrand 75001, Paris (France); FR3605 - MCC/CNRS/UPMC (France); Guillou, T.; Walter, Ph [FR3605 - CC/CNRS/UPMC (France); LAMS - UMR 8220 - CNRS/UPMC - Seine, Paris (France)

    2013-07-01

    Full text: The New AGLAE project aims to establish a world-class facility for non invasive analysis of Cultural Heritage materials. One of the objectives of the New AGLAE project is to increase the x-ray measurement detection, enabling to reduce the beam intensity thus the interaction with sensitive artworks by a ten. Multidisciplinary, the New AGLAE project will provide an exceptional and multipurpose beam line with a performance in spatial resolution, beam stability and a capability of multi-particle detection much higher than for the previous facility. The New AGLAE will give fundamental elements for the understanding of the structure of materials, their composition, properties, and change over time. One of the objectives of this project is to design and set up a new data acquisition system. To reach that purpose, the surface and the number of PIXE detectors have been increased. Indeed, a 10 mm{sup 2} and a 30 mm{sup 3} Si(Li) detectors respectively dedicated to low and high energy measurements, were replaced by a cluster of five 50 mm{sup 2} S.D.D. detectors. If this multi detector enables to decrease the intensity of the incident beam by one order of magnitude, involving less irradiation during the analysis, it can also provide large and/or fast maps. So as to digital the preamp pulses obtained from the detectors, a custom Digital X-ray Processor provides both digital data and control signals compatible to a multiparameter multichannel system. This multiparameter system saves each event from x-ray, gamma and particle detectors and simultaneously the X, Y positions of the beam on the sample as a list file. Furthermore, to draw several-cm-sized maps with a 20/40μm resolution, the scanning of the area originally combines a fast vertical magnetic deflection of the beam and a mechanical movement of the target. To process the data, several homemade software have been developed or updated so as to rebuild any matrix of spectra, to re-bin maps, to process a series of

  6. Image quality of microcalcifications in digital breast tomosynthesis: Effects of projection-view distributions

    OpenAIRE

    Lu, Yao; Chan, Heang-Ping; Wei, Jun; Goodsitt, Mitch; Carson, Paul L.; Hadjiiski, Lubomir; Schmitz, Andrea; Eberhard, Jeffrey W.; Claus, Bernhard E. H.

    2011-01-01

    Purpose: To analyze the effects of projection-view (PV) distribution on the contrast and spatial blurring of microcalcifications on the tomosynthesized slices (X-Y plane) and along the depth (Z) direction for the same radiation dose in digital breast tomosynthesis (DBT).Methods: A GE GEN2 prototype DBT system was used for acquisition of DBT scans. The system acquires PV images from 21 angles in 3° increments over a ±30° range. From these acquired PV images, the authors selected six subsets of...

  7. Imaging Local Polarization in Ferroelectric Thin Films by Coherent X-Ray Bragg Projection Ptychography

    Science.gov (United States)

    Hruszkewycz, S. O.; Highland, M. J.; Holt, M. V.; Kim, Dongjin; Folkman, C. M.; Thompson, Carol; Tripathi, A.; Stephenson, G. B.; Hong, Seungbum; Fuoss, P. H.

    2013-04-01

    We used x-ray Bragg projection ptychography (BPP) to map spatial variations of ferroelectric polarization in thin film PbTiO3, which exhibited a striped nanoscale domain pattern on a high-miscut (001) SrTiO3 substrate. By converting the reconstructed BPP phase image to picometer-scale ionic displacements in the polar unit cell, a quantitative polarization map was made that was consistent with other characterization. The spatial resolution of 5.7 nm demonstrated here establishes BPP as an important tool for nanoscale ferroelectric domain imaging, especially in complex environments accessible with hard x rays.

  8. Normal appearance of the prostate and seminal tract: MR imaging using an endorectal surface coil

    International Nuclear Information System (INIS)

    Kim, Myeong Jin; Lee, Jong Tae; Lee, Moo Sang; Choi, Pil Sik; Hong, Sung Joon; Lee, Yeon Hee; Choi, Hak Yong

    1994-01-01

    To assess the ability of MR imaging with an endorectal surface coil for the depiction of normal anatomical structure of prostate and its adjacent organs. MR imaging using an endorectal surface coil was performed in 23 male patients(age ; 20-75) to evaluate various prostatic and vasovesicular disorders, i. e, 14 cases of ejaculatory problems, 3 cases of hypogonadism, and 4 cases of prostatic cancers and 2 cases of benign prostatic hyperplasia. MR images were obtained with axial, sagittal and coronal fast spin echo long TR/TE images and axial spin echo short TR/TE images. Field of views was 10-12 cm and scan thickness was 3-5 mm. Depiction of normal anatomcial structures was excellent in all cases. On T2WI, zonal anatomy of the prostate and prostatic urethra, urethral crest, and ejaculatory duct were cleary visualized. On T1WI, periprostatic fat plane is more cleary visualized. On transverse images, periprostatic structures were well visualized on T1WI,and on T2WI, anterior fibromuscular stroma, transition zone and peripheral zone could be readily differentiated. Coronal images were more helpful in visualization of both central and peripheral zones. Vas deferens, ejaculatory duct and vermontanum were also more easily defined on these images. Sagittal images was helpful in the depiction of anterior fibromuscular stroma, central zone and peripheral zone with prostatic urethra and ejaculatory duct in a single plane. High resolution MR imaging with an endorectal surface coil can readily visualize the normal anatomy of the prostate and its related structures and may be useful in the evaluation of various diseases of prostate and vasvesicular system

  9. Normal appearance of the prostate and seminal tract: MR imaging using an endorectal surface coil

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myeong Jin; Lee, Jong Tae; Lee, Moo Sang; Choi, Pil Sik; Hong, Sung Joon; Lee, Yeon Hee; Choi, Hak Yong [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1994-06-15

    To assess the ability of MR imaging with an endorectal surface coil for the depiction of normal anatomical structure of prostate and its adjacent organs. MR imaging using an endorectal surface coil was performed in 23 male patients(age ; 20-75) to evaluate various prostatic and vasovesicular disorders, i. e, 14 cases of ejaculatory problems, 3 cases of hypogonadism, and 4 cases of prostatic cancers and 2 cases of benign prostatic hyperplasia. MR images were obtained with axial, sagittal and coronal fast spin echo long TR/TE images and axial spin echo short TR/TE images. Field of views was 10-12 cm and scan thickness was 3-5 mm. Depiction of normal anatomcial structures was excellent in all cases. On T2WI, zonal anatomy of the prostate and prostatic urethra, urethral crest, and ejaculatory duct were cleary visualized. On T1WI, periprostatic fat plane is more cleary visualized. On transverse images, periprostatic structures were well visualized on T1WI,and on T2WI, anterior fibromuscular stroma, transition zone and peripheral zone could be readily differentiated. Coronal images were more helpful in visualization of both central and peripheral zones. Vas deferens, ejaculatory duct and vermontanum were also more easily defined on these images. Sagittal images was helpful in the depiction of anterior fibromuscular stroma, central zone and peripheral zone with prostatic urethra and ejaculatory duct in a single plane. High resolution MR imaging with an endorectal surface coil can readily visualize the normal anatomy of the prostate and its related structures and may be useful in the evaluation of various diseases of prostate and vasvesicular system.

  10. Real-time volumetric image reconstruction and 3D tumor localization based on a single x-ray projection image for lung cancer radiotherapy.

    Science.gov (United States)

    Li, Ruijiang; Jia, Xun; Lewis, John H; Gu, Xuejun; Folkerts, Michael; Men, Chunhua; Jiang, Steve B

    2010-06-01

    To develop an algorithm for real-time volumetric image reconstruction and 3D tumor localization based on a single x-ray projection image for lung cancer radiotherapy. Given a set of volumetric images of a patient at N breathing phases as the training data, deformable image registration was performed between a reference phase and the other N-1 phases, resulting in N-1 deformation vector fields (DVFs). These DVFs can be represented efficiently by a few eigenvectors and coefficients obtained from principal component analysis (PCA). By varying the PCA coefficients, new DVFs can be generated, which, when applied on the reference image, lead to new volumetric images. A volumetric image can then be reconstructed from a single projection image by optimizing the PCA coefficients such that its computed projection matches the measured one. The 3D location of the tumor can be derived by applying the inverted DVF on its position in the reference image. The algorithm was implemented on graphics processing units (GPUs) to achieve real-time efficiency. The training data were generated using a realistic and dynamic mathematical phantom with ten breathing phases. The testing data were 360 cone beam projections corresponding to one gantry rotation, simulated using the same phantom with a 50% increase in breathing amplitude. The average relative image intensity error of the reconstructed volumetric images is 6.9% +/- 2.4%. The average 3D tumor localization error is 0.8 +/- 0.5 mm. On an NVIDIA Tesla C1060 GPU card, the average computation time for reconstructing a volumetric image from each projection is 0.24 s (range: 0.17 and 0.35 s). The authors have shown the feasibility of reconstructing volumetric images and localizing tumor positions in 3D in near real-time from a single x-ray image.

  11. Ground-based thermal imaging of stream surface temperatures: Technique and evaluation

    Science.gov (United States)

    Bonar, Scott A.; Petre, Sally J.

    2015-01-01

    We evaluated a ground-based handheld thermal imaging system for measuring water temperatures using data from eight southwestern USA streams and rivers. We found handheld thermal imagers could provide considerably more spatial information on water temperature (for our unit one image = 19,600 individual temperature measurements) than traditional methods could supply without a prohibitive amount of effort. Furthermore, they could provide measurements of stream surface temperature almost instantaneously compared with most traditional handheld thermometers (e.g., >20 s/reading). Spatial temperature analysis is important for measurement of subtle temperature differences across waterways, and identification of warm and cold groundwater inputs. Handheld thermal imaging is less expensive and equipment intensive than airborne thermal imaging methods and is useful under riparian canopies. Disadvantages of handheld thermal imagers include their current higher expense than thermometers, their susceptibility to interference when used incorrectly, and their slightly lower accuracy than traditional temperature measurement methods. Thermal imagers can only measure surface temperature, but this usually corresponds to subsurface temperatures in well-mixed streams and rivers. Using thermal imaging in select applications, such as where spatial investigations of water temperature are needed, or in conjunction with stationary temperature data loggers or handheld electronic or liquid-in-glass thermometers to characterize stream temperatures by both time and space, could provide valuable information on stream temperature dynamics. These tools will become increasingly important to fisheries biologists as costs continue to decline.

  12. Preliminary Understanding of Surface Plasmon-Enhanced Circular Dichroism Spectroscopy by Single Particle Imaging

    Science.gov (United States)

    Zhan, Kangshu

    Monitoring chiral optical signals of biomolecules as their conformation changes is an important means to study their structures, properties, and functions. Most measurements, however, are ensemble measurements because chiral optical signals from a single biomolecule is often too weak to be detected. In this dissertation, I present my early attempts to study conformational changes of adsorbed proteins by taking advantage of the enhanced electromagnetic (EM) field around a well-designed plasmonic nanofeature. In particular, I discuss the detection of protein adsorption and denaturation on metallic nanoparticles using single particle scattering and CD spectroscopic imaging. Particles of two distinctively different sizes were compared and two different sample protein molecules were studied. A combination of experimental and computational tools was used to simulate and interpret the collected scattering and CD results. The first chapter provides a brief overview of the state-of-art research in CD spectroscopic studies at the single particle level. Three different means to make particles capable of chiral detection are discussed. Various applications beyond single particle imaging are presented to showcase the potential of the described research project, beyond our immediate goals. The second chapter describes my initial characterization of large, metallic, anisotropic nanorods and the establishment of experimental procedures used later for spectrum reconstruction, data visualization and analysis. The physical shape and structure of the particles were imaged by scanning electron microscopy (SEM), the chemical composition by energy dispersive X-ray Spectroscopy (EDS), and the optical properties by darkfield microscopy. An experimental protocol was developed to connect information collected from separate techniques for the same particle, with the aims of discovering any possible structural-property correlation. The reproducibility of the single particle imaging method was

  13. Exploring surface photoreaction dynamics using pixel imaging mass spectrometry (PImMS)

    Science.gov (United States)

    Kershis, Matthew D.; Wilson, Daniel P.; White, Michael G.; John, Jaya John; Nomerotski, Andrei; Brouard, Mark; Lee, Jason W. L.; Vallance, Claire; Turchetta, Renato

    2013-08-01

    A new technique for studying surface photochemistry has been developed using an ion imaging time-of-flight mass spectrometer in conjunction with a fast camera capable of multimass imaging. This technique, called pixel imaging mass spectrometry (PImMS), has been applied to the study of butanone photooxidation on TiO2(110). In agreement with previous studies of this system, it was observed that the main photooxidation pathway for butanone involves ejection of an ethyl radical into vacuum which, as confirmed by our imaging experiment, undergoes fragmentation after ionization in the mass spectrometer. This proof-of-principle experiment illustrates the usefulness and applicability of PImMS technology to problems of interest within the surface science community.

  14. Simulation of Specular Surface Imaging Based on Computer Graphics: Application on a Vision Inspection System

    Directory of Open Access Journals (Sweden)

    Seulin Ralph

    2002-01-01

    Full Text Available This work aims at detecting surface defects on reflecting industrial parts. A machine vision system, performing the detection of geometric aspect surface defects, is completely described. The revealing of defects is realized by a particular lighting device. It has been carefully designed to ensure the imaging of defects. The lighting system simplifies a lot the image processing for defect segmentation and so a real-time inspection of reflective products is possible. To bring help in the conception of imaging conditions, a complete simulation is proposed. The simulation, based on computer graphics, enables the rendering of realistic images. Simulation provides here a very efficient way to perform tests compared to the numerous attempts of manual experiments.

  15. AFM imaging and fractal analysis of surface roughness of AlN epilayers on sapphire substrates

    Energy Technology Data Exchange (ETDEWEB)

    Dallaeva, Dinara, E-mail: dinara.dallaeva@yandex.ru [Brno University of Technology, Faculty of Electrical Engineering and Communication, Physics Department, Technická 8, 616 00 Brno (Czech Republic); Ţălu, Ştefan [Technical University of Cluj-Napoca, Faculty of Mechanical Engineering, Department of AET, Discipline of Descriptive Geometry and Engineering Graphics, 103-105 B-dul Muncii Street, Cluj-Napoca 400641, Cluj (Romania); Stach, Sebastian [University of Silesia, Faculty of Computer Science and Materials Science, Institute of Informatics, Department of Biomedical Computer Systems, ul. Będzińska 39, 41-205 Sosnowiec (Poland); Škarvada, Pavel; Tománek, Pavel; Grmela, Lubomír [Brno University of Technology, Faculty of Electrical Engineering and Communication, Physics Department, Technická 8, 616 00 Brno (Czech Republic)

    2014-09-01

    Graphical abstract: - Highlights: • We determined the complexity of 3D surface roughness of aluminum nitride layers. • We used atomic force microscopy and analyzed their fractal geometry. • We determined the fractal dimension of surface roughness of aluminum nitride layers. • We determined the dependence of layer morphology on substrate temperature. - Abstract: The paper deals with AFM imaging and characterization of 3D surface morphology of aluminum nitride (AlN) epilayers on sapphire substrates prepared by magnetron sputtering. Due to the effect of temperature changes on epilayer's surface during the fabrication, a surface morphology is studied by combination of atomic force microscopy (AFM) and fractal analysis methods. Both methods are useful tools that may assist manufacturers in developing and fabricating AlN thin films with optimal surface characteristics. Furthermore, they provide different yet complementary information to that offered by traditional surface statistical parameters. This combination is used for the first time for measurement on AlN epilayers on sapphire substrates, and provides the overall 3D morphology of the sample surfaces (by AFM imaging), and reveals fractal characteristics in the surface morphology (fractal analysis)

  16. Surface phenomena revealed by in situ imaging: studies from adhesion, wear and cutting

    Science.gov (United States)

    Viswanathan, Koushik; Mahato, Anirban; Yeung, Ho; Chandrasekar, Srinivasan

    2017-03-01

    Surface deformation and flow phenomena are ubiquitous in mechanical processes. In this work we present an in situ imaging framework for studying a range of surface mechanical phenomena at high spatial resolution and across a range of time scales. The in situ framework is capable of resolving deformation and flow fields quantitatively in terms of surface displacements, velocities, strains and strain rates. Three case studies are presented demonstrating the power of this framework for studying surface deformation. In the first, the origin of stick-slip motion in adhesive polymer interfaces is investigated, revealing a intimate link between stick-slip and surface wave propagation. Second, the role of flow in mediating formation of surface defects and wear particles in metals is analyzed using a prototypical sliding process. It is shown that conventional post-mortem observation and inference can lead to erroneous conclusions with regard to formation of surface cracks and wear particles. The in situ framework is shown to unambiguously capture delamination wear in sliding. Third, material flow and surface deformation in a typical cutting process is analyzed. It is shown that a long-standing problem in the cutting of annealed metals is resolved by the imaging, with other benefits such as estimation of energy dissipation and power from the flow fields. In closure, guidelines are provided for profitably exploiting in situ observations to study large-strain deformation, flow and friction phenomena at surfaces that display a variety of time-scales.

  17. Projection of the Liquidus Surface of the Co - Sn - Bi System

    Science.gov (United States)

    Abilov, Ch. I.; Allazov, M. R.; Sadygova, S. G.

    2016-11-01

    The crystallization behavior of phases in alloys of the Co - Sn - Bi system is studied by the methods of differential thermal (DTA), x-ray phase (XRP) and x-ray diffraction (XRD) analyses and hardness measurement. The projection of the liquidus surface is plotted. The boundaries of layering, the development of the monovariant processes, and the coordinates of the nonvariant equilibrium compositions are determined. Compositions of (Co3Sn2)1 - x Bi x solid solutions suitable for the production of antifriction materials are suggested.

  18. Condensed listing of surface boreholes at the Waste Isolation Pilot Plant Project through 31 December 1995

    International Nuclear Information System (INIS)

    Hill, L.R.; Aguilar, R.; Mercer, J.W.; Newman, G.

    1997-01-01

    This report contains a condensed listing of Waste Isolation Pilot Plant (WIPP) project surface boreholes drilled for the purpose of site selection and characterization through 31 December 1995. The US Department of Energy (DOE) sponsored the drilling activities, which were conducted primarily by Sandia National Laboratories. The listing provides physical attributes such as location (township, range, section, and state-plane coordinates), elevation, and total borehole depth, as well as the purpose for the borehole, drilling dates, and information about extracted cores. The report also presents the hole status (plugged, testing, monitoring, etc.) and includes salient findings and references. Maps with borehole locations and times-of-drilling charts are included

  19. 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.

  20. 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

  1. Clinical application of synthesized brain surface imaging for preoperative simulation of brain biopsy under local anesthesia

    International Nuclear Information System (INIS)

    Ogura, Yuko; Katada, Kazuhiro; Imai, Fumihiro; Fujisawa, Kazuhisa; Takeshita, Gen; Kanno, Tetsuo; Koga, Sukehiko

    1994-01-01

    Surface anatomy scanning (SAS) is the technique which permits the direct visualization of brain surface structures, including cortical sulci, guri, subcortical lesions as well as skin markings for craniotomy. A synthesized brain surface image is a technique that combines MR angiography (MRA) with SAS, and it proposed by us for detecting cerebral superficial veins with these surface structures on the same image. The purpose of this report is to present the result of applying the synthesized brain surface image to the preoperative simulation of biopsy under local anesthesia in 2 cases of multiple metastatic brain tumors. The parameters for SAS were TR/TE=50/40 msec, flip angle=60deg by the fast T 2 technique using refocused FID in steady-state (STERF technique). SAS images were processed by gray scale reversal. The MRA data were acquired with two-dimensional time of flight (TOF) sequence after intravenous administration of Gd-DTPA. Before imaging, the water-filled plastic tubes were placed on the patients scalp as markings for craniotomy. Their positions were planned by the neurosurgeons. On SAS, the markings for burr-hole appeared located above the tumors. However on the synthesized brain surface images, the positions of burr-hole were considered to be inadequate, since superficial cerebral vein and sinus were also visualized in the area of the markings. From these results, the positions of burr-hole were reset to avoid the venous structures, and so as to include the lesions in operations. The biopsies were performed successfully and safely because the venous structure could be excluded from the operative field. By this technique it was easy to confirm the relationships among lesions, skin markings and venous structures. The technique described appears to be a useful method for preoperative simulation of biopsies for multiple metastatic brain tumors under local anesthesia. (author)

  2. Imaging performance of annular apertures. VI - Limitations by optical surface deviations

    Science.gov (United States)

    Tschunko, Hubert F. A.

    1987-01-01

    The performance of optical systems is limited by imperfect optical surfaces that degrade the images below the level set by wave theoretical limits. The central irradiance functions are derived for slit and circular apertures with five distributions of wavefront errors and for a range of maximal wavefront deviations. For practical frequency of occurrence distributions of wavefront deviations, the point spread and the image energy integral functions are determined. Practical performances of optical systems are derived and performance limits discussed.

  3. Quantitative Evaluation of Surface Color of Tomato Fruits Cultivated in Remote Farm Using Digital Camera Images

    Science.gov (United States)

    Hashimoto, Atsushi; Suehara, Ken-Ichiro; Kameoka, Takaharu

    To measure the quantitative surface color information of agricultural products with the ambient information during cultivation, a color calibration method for digital camera images and a remote monitoring system of color imaging using the Web were developed. Single-lens reflex and web digital cameras were used for the image acquisitions. The tomato images through the post-ripening process were taken by the digital camera in both the standard image acquisition system and in the field conditions from the morning to evening. Several kinds of images were acquired with the standard RGB color chart set up just behind the tomato fruit on a black matte, and a color calibration was carried out. The influence of the sunlight could be experimentally eliminated, and the calibrated color information consistently agreed with the standard ones acquired in the system through the post-ripening process. Furthermore, the surface color change of the tomato on the tree in a greenhouse was remotely monitored during maturation using the digital cameras equipped with the Field Server. The acquired digital color images were sent from the Farm Station to the BIFE Laboratory of Mie University via VPN. The time behavior of the tomato surface color change during the maturing process could be measured using the color parameter calculated based on the obtained and calibrated color images along with the ambient atmospheric record. This study is a very important step in developing the surface color analysis for both the simple and rapid evaluation of the crop vigor in the field and to construct an ambient and networked remote monitoring system for food security, precision agriculture, and agricultural research.

  4. Mass spectrometry imaging of surface lipids on intact Drosophila melanogaster flies

    Czech Academy of Sciences Publication Activity Database

    Kaftan, Filip; Vrkoslav, Vladimír; Kynast, P.; Kulkarni, P.; Böcker, S.; Cvačka, Josef; Knaden, M.; Svatoš, Aleš

    2014-01-01

    Roč. 49, č. 3 (2014), s. 223-232 ISSN 1076-5174 R&D Projects: GA ČR GA203/09/0139 Institutional support: RVO:61388963 Keywords : MALDI * laser desorption * mass spectrometric imaging * fruit flies * neutral lipids * sex pheromones * mass shift correction Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.379, year: 2014

  5. AFM imaging and analysis of local mechanical properties for detection of surface pattern of functional groups

    Czech Academy of Sciences Publication Activity Database

    Knotek, P.; Chánová, Eliška; Rypáček, František

    2013-01-01

    Roč. 33, č. 4 (2013), s. 1963-1968 ISSN 0928-4931 R&D Projects: GA ČR GAP108/11/1857; GA ČR GPP108/12/P624 Institutional support: RVO:61389013 Keywords : phase shift image * AFAM * force spectroscopy Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.736, year: 2013

  6. Image potential resonances of the aluminum (100) surface; Bildpotentialresonanzen der Aluminium-(100)-Oberflaeche

    Energy Technology Data Exchange (ETDEWEB)

    Winter, Matthias

    2011-07-08

    Image-potential resonances on the (100) surface of pure Aluminum are investigated experimentally and theoretically. The experiments are conducted both energy- and time-resolved using the method of two-photon photoemission spectroscopy. The main attention of the theoretical examination and extensive numerical calculations is devoted to the interaction between surface and bulk states. Image-potential resonances on Al(100) are a system in which a complete series of discrete Rydberg states strongly couples to a continuum of states. As a simple metal it also provides a good opportunity to test theoretical models of the structure of the potential at metal surfaces. This work represents the first high-resolution investigation of image-potential resonances with such strong resonance character. For the first time, it is demonstrated experimentally that isolated image-potential resonances exist on an Aluminum surface. On the (100) surface of Aluminum the second through fifth image-potential resonance are resolved and both, their energies and lifetimes are measured. The binding energies of the image-potential resonances form a Rydberg series of states {epsilon}{sub n}=-(0,85 eV)/((n+a){sup 2}). Within the accuracy of the measurement it is not necessary to introduce a quantum defect a (a=0.022{+-}0.035). Using angle-resolved two-photon photoemission spectroscopy the effective mass of electrons in the second image-potential resonance is measured to 1.01{+-}0.11 electron masses. The lifetimes of the resonances increase as {tau}{sub n} = (1.0{+-}0.2)fs.n{sup 3} starting from n=2. Calculations using the density matrix formalism show that the experimentally observed lifetimes can be explained well by electrons decaying into the bulk. The effect of resonance trapping leads to extended lifetimes in the process. Contrary to common theoretical models of image-potential states at metal surfaces the first image-potential resonance cannot be observed in two-photon photoemission on Al(100

  7. Fusion and display of 3D spect and MR images registered by a surface fitting method

    International Nuclear Information System (INIS)

    Oghabian, M.A.; Kaboli, P.

    2002-01-01

    Since 3D medical images such as SPECT and MRI are taken under different positioning and imaging parameters, interpretation of them, as reconstructed originally, dose not provide an easy and accurate understanding of similarities and differences between them. The problem becomes more crucial where a clinician would like to map accurately region of interest from one study to the other, by which some surgical or therapeutical planning may be based. the research presented here is an investigation into the problems of the registration and display of brain images obtained by different imaging modalities. Following the introduction of an efficient method some clinical useful application of the registration and superimposition were also defined. The various widely used registration algorithms were first studied and their advantages and disadvantages of each method were evaluated. In this approach, an edge-based algorithm (called surface fitting), which are based on a least-square-distance matching, were suggested for registering of brain images. This algorithm minimizes the sum of square-distances between the two surfaces obtained from two modalities. The minimization is performed to find a set of six geometrical transformation parameters (3 shifts and 3 rotations) which indicate how one surface should be transformed in order to match with the other surface

  8. A high-throughput surface plasmon resonance biosensor based on differential interferometric imaging

    International Nuclear Information System (INIS)

    Wang, Daqian; Ding, Lili; Zhang, Wei; Zhang, Enyao; Yu, Xinglong; Luo, Zhaofeng; Ou, Huichao

    2012-01-01

    A new high-throughput surface plasmon resonance (SPR) biosensor based on differential interferometric imaging is reported. The two SPR interferograms of the sensing surface are imaged on two CCD cameras. The phase difference between the two interferograms is 180°. The refractive index related factor (RIRF) of the sensing surface is calculated from the two simultaneously acquired interferograms. The simulation results indicate that the RIRF exhibits a linear relationship with the refractive index of the sensing surface and is unaffected by the noise, drift and intensity distribution of the light source. The affinity and kinetic information can be extracted in real time from continuously acquired RIRF distributions. The results of refractometry experiments show that the dynamic detection range of SPR differential interferometric imaging system can be over 0.015 refractive index unit (RIU). High refractive index resolution is down to 0.45 RU (1 RU = 1 × 10 −6 RIU). Imaging and protein microarray experiments demonstrate the ability of high-throughput detection. The aptamer experiments demonstrate that the SPR sensor based on differential interferometric imaging has a great capability to be implemented for high-throughput aptamer kinetic evaluation. These results suggest that this biosensor has the potential to be utilized in proteomics and drug discovery after further improvement. (paper)

  9. MIT Project Apophis: Surface Evaulation & Tomography (SET) Mission Study for the April 2029 Earth Encounter

    Science.gov (United States)

    Binzel, R. P.; Earle, A. M.; Vanatta, M.; Miller, D. W.

    2017-12-01

    Nature is providing a once-per-thousand year opportunity to study the geophysical outcome induced on an unprecedentedly large (350 meter) asteroid making an extremely close passage by the Earth (inside the distance of geosynchronous satellites) on Friday April 13, 2029. The aircraft carrier-sized (estimated 20 million metric ton) asteroid is named Apophis. While many previous spacecraft missions have studied asteroids, none has ever had the opportunity to study "live" the outcome of planetary tidal forces on their shapes, spin states, surface geology, and internal structure. Beyond the science interest directly observing this planetary process, the Apophis encounter provides an invaluable opportunity to gain knowledge for any eventuality of a known asteroid found to be on a certain impact trajectory. MIT's Project Apophis [1] is our response to nature's generous opportunity by developing a detailed mission concept for sending a spacecraft to orbit Apophis with the objectives of surveying its surface and interior structure before, during, and after its 2029 near-Earth encounter. The Surface Evaluation & Tomography (SET) mission concept we present is designed toward accomplishing three key science objectives: (1) bulk physical characterization, (2) internal structure, and (3) long-term orbit tracking. For its first mission objective, SET will study Apophis' bulk properties, including: shape, size, mass, volume, bulk density, surface geology, and composition, rotation rate, and spin state. The second mission objective is to characterize Apophis' internal structure before and after the encounter to determine its strength and cohesion - including tidally induced changes. Finally, the third objective studies the process of thermal re-radiation and consequential Yarkovsky drift, whose results will improve orbit predictions for Apophis as well as other potentially hazardous asteroids. [1] https://eapsweb.mit.edu/mit-project-apophis

  10. Surface radiological free release program for the Battelle Columbus Laboratory Decommissioning Project

    International Nuclear Information System (INIS)

    Horton, C.N.

    1995-01-01

    This paper was prepared for the Second Residual Radioactivity and Recycling Criteria Workshop and discusses decommissioning and decontamination activities at the Battelle Columbus Laboratories Decommissioning Project (BCLDP). The BCLDP is a joint effort between the Department of Energy (DOE) and Battelle Columbus Operations to decontaminate fifteen Battelle-owned buildings contaminated with DOE radioactive materials. The privately owned buildings located across the street from The Ohio State University campus became contaminated with natural uranium and thorium during nuclear research activities. BCLDP waste management is supported by an extensive radiological free-release program. Miscellaneous materials and building surfaces have been free-released from the BCLDP. The free-release program has substantially reduced radioactive waste volumes and supported waste minimization. Free release for unrestricted use has challenged regulators and NRC licensees since the development of early surface-release criteria. This paper discusses the surface radiological free-release program incorporated by the BCLDP and the historical development of the surface radiological free-release criteria. Concerns regarding radiological free-release criteria are also presented. (author)

  11. Final report on the surface-based investigation (phase 1) at the Mizunami Underground Laboratory project

    International Nuclear Information System (INIS)

    Saegusa, Hiromitsu; Seno, Yasuhiro; Nakama, Shigeo; Tsuruta, Tadahiko; Amano, Kenji; Takeuchi, Ryuji; Matsuoka, Toshiyuki; Onoe, Hironori; Mizuno, Takashi; Ohyama, Takuya; Hama, Katsuhiro; Sato, Toshinori; Kuji, Masayoshi; Kuroda, Hidetaka; Semba, Takeshi; Uchida, Masahiro; Sugihara, Kozo; Sakamaki, Masanori; Iwatsuki, Teruki

    2007-03-01

    The Mizunami Underground Laboratory (MIU) Project is a comprehensive research project investigating the deep underground environment within crystalline rock being conducted by Japan Atomic Energy Agency at Mizunami City in Gifu Prefecture, central Japan and its role is defined in 'Framework for Nuclear Energy Policy' by Japan Atomic Energy Commission. The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III), with a total duration of 20 years. The overall project goals of the MIU Project from Phase I through to Phase III are: 1) to establish techniques for investigation, analysis and assessment of the deep geological environment, and 2) to develop a range of engineering for deep underground application. During Phase I, the overall project goals were supported by Phase I goals. For the overall project goals 1), the Phase I goals were set to construct models of the geological environment from all surface-based investigation results that describe the geological environment prior to excavation and predict excavation response. For the overall project goals 2), the Phase I goals were set to formulate detailed design concepts and a construction plan for the underground facilities. This report summarizes the Phase I investigation which was completed in March 2005. The authors believe this report will make an important milestone, since this report clarifies how the Phase I goals are achieved and evaluate the future issues thereby direct the research which will be conducted during Phase II. With regard to the overall project goals 1), 'To establish techniques for investigation, analysis and assessment of the deep geological environment,' a step-wise investigation was conducted by iterating investigation, interpretation, and assessment, thereby understanding of geologic environment was progressively and effectively improved with progress of investigation. An optimal procedure from

  12. Portable hyperspectral fluorescence imaging system for detection of biofilms on stainless steel surfaces

    Science.gov (United States)

    Jun, Won; Lee, Kangjin; Millner, Patricia; Sharma, Manan; Chao, Kuanglin; Kim, Moon S.

    2008-04-01

    A rapid nondestructive technology is needed to detect bacterial contamination on the surfaces of food processing equipment to reduce public health risks. A portable hyperspectral fluorescence imaging system was used to evaluate potential detection of microbial biofilm on stainless steel typically used in the manufacture of food processing equipment. Stainless steel coupons were immersed in bacterium cultures, such as E. coli, Pseudomonas pertucinogena, Erwinia chrysanthemi, and Listeria innocula. Following a 1-week exposure, biofilm formations were assessed using fluorescence imaging. In addition, the effects on biofilm formation from both tryptic soy broth (TSB) and M9 medium with casamino acids (M9C) were examined. TSB grown cells enhance biofilm production compared with M9C-grown cells. Hyperspectral fluorescence images of the biofilm samples, in response to ultraviolet-A (320 to 400 nm) excitation, were acquired from approximately 416 to 700 nm. Visual evaluation of individual images at emission peak wavelengths in the blue revealed the most contrast between biofilms and stainless steel coupons. Two-band ratios compared with the single-band images increased the contrast between the biofilm forming area and stainless steel coupon surfaces. The 444/588 nm ratio images exhibited the greatest contrast between the biofilm formations and stainless coupon surfaces.

  13. In-Situ Imaging and Quantification of Tritium Surface Contamination via Coherent Fiber Bundle

    International Nuclear Information System (INIS)

    Gentile, Charles A.; Parker, John J.; Zweben, Stewart J.

    2001-01-01

    Princeton Plasma Physics Laboratory (PPPL) has developed a method of imaging tritium on in-situ surfaces for the purpose of real-time data collection. This method expands upon a previous tritium imaging concept, also developed at PPPL. Enhancements include an objective lens coupled to the entry aperture of a coherent fiber optic (CFO) bundle, and a relay lens connecting the exit aperture of the fiber bundle to an intensifier tube and a charge-coupled device (CCD) camera. The system has been specifically fabricated for use in determining tritium concentrations on first wall materials. One potential complication associated with the development of D-T [deuterium-tritium] fueled fusion reactors is the deposition of tritium (i.e., co-deposited layer) on the surface of the primary wall of the vacuum vessel. It would be advantageous to implement a process to accurately determine tritium distribution on these inner surfaces. This fiber optic imaging device provides a highly practical method for determining the location, concentration, and activity of surface tritium deposition. In addition, it can be employed for detection of tritium ''hot-spots'' and ''hide-out'' regions present on the surfaces being imaged

  14. An Effective Surface Modeling Method for Car Styling from a Side-View Image

    Institute of Scientific and Technical Information of China (English)

    LIBao-jun; ZHANGXue-fang; LVZhang-quan; QIYi-chao

    2014-01-01

    We introduce an almost-automatic technique for generating 3D car styling surface models based on a single side-view image. Our approach combines the prior knowledge of car styling and deformable curve network model to obtain an automatic modeling process. Firstly, we define the consistent parameterized curve template for 2D and 3D case respectivelyby analyzingthe characteristic lines for car styling. Then, a semi-automatic extraction from a side-view car image is adopted. Thirdly, statistic morphable model of 3D curve network isused to get the initial solution with sparse point constraints.Withonly afew post-processing operations, the optimized curve network models for creating surfaces are obtained. Finally, the styling surfaces are automatically generated using template-based parametric surface modeling method. More than 50 3D curve network models are constructed as the morphable database. We show that this intelligent modeling toolsimplifiesthe exhausted modeling task, and also demonstratemeaningful results of our approach.

  15. 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.

  16. 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.

  17. Automated 3D closed surface segmentation: application to vertebral body segmentation in CT images.

    Science.gov (United States)

    Liu, Shuang; Xie, Yiting; Reeves, Anthony P

    2016-05-01

    A fully automated segmentation algorithm, progressive surface resolution (PSR), is presented in this paper to determine the closed surface of approximately convex blob-like structures that are common in biomedical imaging. The PSR algorithm was applied to the cortical surface segmentation of 460 vertebral bodies on 46 low-dose chest CT images, which can be potentially used for automated bone mineral density measurement and compression fracture detection. The target surface is realized by a closed triangular mesh, which thereby guarantees the enclosure. The surface vertices of the triangular mesh representation are constrained along radial trajectories that are uniformly distributed in 3D angle space. The segmentation is accomplished by determining for each radial trajectory the location of its intersection with the target surface. The surface is first initialized based on an input high confidence boundary image and then resolved progressively based on a dynamic attraction map in an order of decreasing degree of evidence regarding the target surface location. For the visual evaluation, the algorithm achieved acceptable segmentation for 99.35 % vertebral bodies. Quantitative evaluation was performed on 46 vertebral bodies and achieved overall mean Dice coefficient of 0.939 (with max [Formula: see text] 0.957, min [Formula: see text] 0.906 and standard deviation [Formula: see text] 0.011) using manual annotations as the ground truth. Both visual and quantitative evaluations demonstrate encouraging performance of the PSR algorithm. This novel surface resolution strategy provides uniform angular resolution for the segmented surface with computation complexity and runtime that are linearly constrained by the total number of vertices of the triangular mesh representation.

  18. Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM) phase images

    OpenAIRE

    G. Helas; M. O. Andreae

    2008-01-01

    We show that atomic force microscopy (AFM) phase images can reveal surface features of soil dust particles, which are not evident using other microscopic methods. The non-contact AFM method is able to resolve topographical structures in the nanometer range as well as to uncover repulsive atomic forces and attractive van der Waals' forces, and thus gives insight to surface properties. Though the method does not allow quantitative assignment in terms of chemical compound description, it clearly...

  19. Surface coil imaging of the spine using fast sequences: Improvement of intensity profile and contrast behavior

    International Nuclear Information System (INIS)

    Requardt, H.; Deimling, M.; Weber, H.

    1986-01-01

    Sagittal and axial images obtained using a surface coil suffer from the extreme intensity profile caused by physical properties of the coil and the anatomic entity of subcutaneous fat. The authors present a measuring device that reduces these disadvantages by means of Helmholtz-type coils, and sequences that reduce the fat signal by dephasing its signal part. The extremely short repetition time (<30 msec) allows acquisition times shorter than 10 sec. Breath-holding for this short period to avoid movement artifacts is possible. Images are presented that illustrate the enhanced contrast of spinal tissue and surrounding structures. Comparisons are made with spin-echo and CHESS images

  20. A portable UV-fluorescence multispectral imaging system for the analysis of painted surfaces

    Science.gov (United States)

    Comelli, Daniela; Valentini, Gianluca; Nevin, Austin; Farina, Andrea; Toniolo, Lucia; Cubeddu, Rinaldo

    2008-08-01

    A portable fluorescence multispectral imaging system was developed and has been used for the analysis of artistic surfaces. The imaging apparatus exploits two UV lamps for fluorescence excitation and a liquid crystal tunable filter coupled to a low-noise charge coupled device as the image detector. The main features of the system are critically presented, outlining the assets, drawbacks, and practical considerations of portability. A multivariate statistical treatment of spectral data is further considered. Finally, the in situ analysis with the new apparatus of recently restored Renaissance wall paintings is presented.

  1. On the effect of image states on resonant neutralization of hydrogen anions near metal surfaces

    International Nuclear Information System (INIS)

    Chakraborty, Himadri S.; Niederhausen, Thomas; Thumm, Uwe

    2005-01-01

    We directly assess the role of image state electronic structures on the ion-survival by comparing the resonant charge transfer dynamics of hydrogen anions near Pd(1 1 1), Pd(1 0 0), and Ag(1 1 1) surfaces. Our simulations show that image states that are degenerate with the metal conduction band favor the recapture of electrons by outgoing ions. In sharp contrast, localized image states that occur inside the band gap hinder the recapture process and thus enhance the ion-neutralization probability

  2. Factors affecting the effectiveness of a projection dephaser in 2D gradient-echo imaging

    International Nuclear Information System (INIS)

    Bakker, Chris J G; Peters, Nicky H G M; Vincken, Koen L; Bom, Martijn van der; Seppenwoolde, Jan-Henry

    2007-01-01

    Projection dephasers are often used for background suppression and dynamic range improvement in thick-slab 2D imaging in order to promote the visibility of subslice structures, e.g., blood vessels and interventional devices. In this study, we explored the factors that govern the effectiveness of a projection dephaser by simulations and phantom experiments. This was done for the ideal case of a single subslice hyper- or hypointensity against a uniform background in the absence of susceptibility effects. Simulations and experiments revealed a pronounced influence of the slice profile, the nominal flip angle and the TE and TR of the acquisition, the size, intraslice position and MR properties of the subslice structure, and T 1 of the background. The complexity of the ideal case points to the necessity of additional explorations when considering the use of projection dephasers under less ideal conditions, e.g., in the presence of tissue heterogeneities and susceptibility gradients

  3. 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)

  4. 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.

  5. 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.

  6. SU-C-204-06: Surface Imaging for the Set-Up of Proton Post-Mastectomy Chestwall Irradiation: Gated Images Vs Non Gated Images

    International Nuclear Information System (INIS)

    Batin, E; Depauw, N; MacDonald, S; Lu, H

    2015-01-01

    Purpose: Historically, the set-up for proton post-mastectomy chestwall irradiation at our institution started with positioning the patient using tattoos and lasers. One or more rounds of orthogonal X-rays at gantry 0° and beamline X-ray at treatment gantry angle were then taken to finalize the set-up position. As chestwall targets are shallow and superficial, surface imaging is a promising tool for set-up and needs to be investigated Methods: The orthogonal imaging was entirely replaced by AlignRT™ (ART) images. The beamline X-Ray image is kept as a confirmation, based primarily on three opaque markers placed on skin surface instead of bony anatomy. In the first phase of the process, ART gated images were used to set-up the patient and the same specific point of the breathing curve was used every day. The moves (translations and rotations) computed for each point of the breathing curve during the first five fractions were analyzed for ten patients. During a second phase of the study, ART gated images were replaced by ART non-gated images combined with real-time monitoring. In both cases, ART images were acquired just before treatment to access the patient position compare to the non-gated CT. Results: The average difference between the maximum move and the minimum move depending on the chosen breathing curve point was less than 1.7 mm for all translations and less than 0.7° for all rotations. The average position discrepancy over the course of treatment obtained by ART non gated images combined to real-time monitoring taken before treatment to the planning CT were smaller than the average position discrepancy obtained using ART gated images. The X-Ray validation images show similar results with both ART imaging process. Conclusion: The use of ART non gated images combined with real time imaging allows positioning post-mastectomy chestwall patients in less than 3 mm / 1°

  7. SU-C-204-06: Surface Imaging for the Set-Up of Proton Post-Mastectomy Chestwall Irradiation: Gated Images Vs Non Gated Images

    Energy Technology Data Exchange (ETDEWEB)

    Batin, E; Depauw, N; MacDonald, S; Lu, H [Massachusetts General Hospital, Boston, MA (United States)

    2015-06-15

    Purpose: Historically, the set-up for proton post-mastectomy chestwall irradiation at our institution started with positioning the patient using tattoos and lasers. One or more rounds of orthogonal X-rays at gantry 0° and beamline X-ray at treatment gantry angle were then taken to finalize the set-up position. As chestwall targets are shallow and superficial, surface imaging is a promising tool for set-up and needs to be investigated Methods: The orthogonal imaging was entirely replaced by AlignRT™ (ART) images. The beamline X-Ray image is kept as a confirmation, based primarily on three opaque markers placed on skin surface instead of bony anatomy. In the first phase of the process, ART gated images were used to set-up the patient and the same specific point of the breathing curve was used every day. The moves (translations and rotations) computed for each point of the breathing curve during the first five fractions were analyzed for ten patients. During a second phase of the study, ART gated images were replaced by ART non-gated images combined with real-time monitoring. In both cases, ART images were acquired just before treatment to access the patient position compare to the non-gated CT. Results: The average difference between the maximum move and the minimum move depending on the chosen breathing curve point was less than 1.7 mm for all translations and less than 0.7° for all rotations. The average position discrepancy over the course of treatment obtained by ART non gated images combined to real-time monitoring taken before treatment to the planning CT were smaller than the average position discrepancy obtained using ART gated images. The X-Ray validation images show similar results with both ART imaging process. Conclusion: The use of ART non gated images combined with real time imaging allows positioning post-mastectomy chestwall patients in less than 3 mm / 1°.

  8. Imaging and reconstruction of cell cortex structures near the cell surface

    Science.gov (United States)

    Jin, Luhong; Zhou, Xiaoxu; Xiu, Peng; Luo, Wei; Huang, Yujia; Yu, Feng; Kuang, Cuifang; Sun, Yonghong; Liu, Xu; Xu, Yingke

    2017-11-01

    Total internal reflection fluorescence microscopy (TIRFM) provides high optical sectioning capability and superb signal-to-noise ratio for imaging of cell cortex structures. The development of multi-angle (MA)-TIRFM permits high axial resolution imaging and reconstruction of cellular structures near the cell surface. Cytoskeleton is composed of a network of filaments, which are important for maintenance of cell function. The high-resolution imaging and quantitative analysis of filament organization would contribute to our understanding of cytoskeleton regulation in cell. Here, we used a custom-developed MA-TIRFM setup, together with stochastic photobleaching and single molecule localization method, to enhance the lateral resolution of TIRFM imaging to about 100 nm. In addition, we proposed novel methods to perform filament segmentation and 3D reconstruction from MA-TIRFM images. Furthermore, we applied these methods to study the 3D localization of cortical actin and microtubule structures in U373 cancer cells. Our results showed that cortical actins localize ∼ 27 nm closer to the plasma membrane when compared with microtubules. We found that treatment of cells with chemotherapy drugs nocodazole and cytochalasin B disassembles cytoskeletal network and induces the reorganization of filaments towards the cell periphery. In summary, this study provides feasible approaches for 3D imaging and analyzing cell surface distribution of cytoskeletal network. Our established microscopy platform and image analysis toolkits would facilitate the study of cytoskeletal network in cells.

  9. Seasonal Composite Raster Images for Sea Surface Temperature in the Gulf of Maine for Stellwagen Bank NMS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of sea surface temperature (SST) in the Gulf of Maine. These raster images are seasonal composites, and were...

  10. Monthly Composite Raster Images for Sea Surface Temperature in the Gulf of Maine for Stellwagen Bank NMS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of sea surface temperature (SST) in the Gulf of Maine. These raster images are monthly composites, and were...

  11. Grand Composite Raster Images for Sea Surface Temperature in the Gulf of Maine for Stellwagen Bank NMS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of sea surface temperature (SST) in the Gulf of Maine. These raster images are a composite of several years...

  12. High spatial resolution quantitative MR images: an experimental study of dedicated surface coils

    International Nuclear Information System (INIS)

    Gensanne, D; Josse, G; Lagarde, J M; Vincensini, D

    2006-01-01

    Measuring spin-spin relaxation times (T 2 ) by quantitative MR imaging represents a potentially efficient tool to evaluate the physicochemical properties of various media. However, noise in MR images is responsible for uncertainties in the determination of T 2 relaxation times, which limits the accuracy of parametric tissue analysis. The required signal-to-noise ratio (SNR) depends on the T 2 relaxation behaviour specific to each tissue. Thus, we have previously shown that keeping the uncertainty in T 2 measurements within a limit of 10% implies that SNR values be greater than 100 and 300 for mono- and biexponential T 2 relaxation behaviours, respectively. Noise reduction can be obtained either by increasing the voxel size (i.e., at the expense of spatial resolution) or by using high sensitivity dedicated surface coils (which allows us to increase SNR without deteriorating spatial resolution in an excessive manner). However, surface coil sensitivity is heterogeneous, i.e., it- and hence SNR-decreases with increasing depth, and the more so as the coil radius is smaller. The use of surface coils is therefore limited to the analysis of superficial structure such as the hypodermic tissue analysed here. The aim of this work was to determine the maximum limits of spatial resolution and depth compatible with reliable in vivo T 2 quantitative MR images using dedicated surface coils available on various clinical MR scanners. The average thickness of adipose tissue is around 15 mm, and the results obtained have shown that obtaining reliable biexponential relaxation analysis requires a minimum achievable voxel size of 13 mm 3 for a conventional volume birdcage coil and only of 1.7 mm 3 for the smallest available surface coil (23 mm in diameter). Further improvement in spatial resolution allowing us to detect low details in MR images without deteriorating parametric T 2 images can be obtained by image filtering. By using the non-linear selective blurring filter described in a

  13. Surface scanning through a cylindrical tank of coupling fluid for clinical microwave breast imaging exams

    International Nuclear Information System (INIS)

    Pallone, Matthew J.; Meaney, Paul M.; Paulsen, Keith D.

    2012-01-01

    Purpose: Microwave tomographic image quality can be improved significantly with prior knowledge of the breast surface geometry. The authors have developed a novel laser scanning system capable of accurately recovering surface renderings of breast-shaped phantoms immersed within a cylindrical tank of coupling fluid which resides completely external to the tank (and the aqueous environment) and overcomes the challenges associated with the optical distortions caused by refraction from the air, tank wall, and liquid bath interfaces. Methods: The scanner utilizes two laser line generators and a small CCD camera mounted concentrically on a rotating gantry about the microwave imaging tank. Various calibration methods were considered for optimizing the accuracy of the scanner in the presence of the optical distortions including traditional ray tracing and image registration approaches. In this paper, the authors describe the construction and operation of the laser scanner, compare the efficacy of several calibration methods—including analytical ray tracing and piecewise linear, polynomial, locally weighted mean, and thin-plate-spline (TPS) image registrations—and report outcomes from preliminary phantom experiments. Results: The results show that errors in calibrating camera angles and position prevented analytical ray tracing from achieving submillimeter accuracy in the surface renderings obtained from our scanner configuration. Conversely, calibration by image registration reliably attained mean surface errors of less than 0.5 mm depending on the geometric complexity of the object scanned. While each of the image registration approaches outperformed the ray tracing strategy, the authors found global polynomial methods produced the best compromise between average surface error and scanner robustness. Conclusions: The laser scanning system provides a fast and accurate method of three dimensional surface capture in the aqueous environment commonly found in microwave

  14. [A Method to Reconstruct Surface Reflectance Spectrum from Multispectral Image Based on Canopy Radiation Transfer Model].

    Science.gov (United States)

    Zhao, Yong-guang; Ma, Ling-ling; Li, Chuan-rong; Zhu, Xiao-hua; Tang, Ling-li

    2015-07-01

    Due to the lack of enough spectral bands for multi-spectral sensor, it is difficult to reconstruct surface retlectance spectrum from finite spectral information acquired by multi-spectral instrument. Here, taking into full account of the heterogeneity of pixel from remote sensing image, a method is proposed to simulate hyperspectral data from multispectral data based on canopy radiation transfer model. This method first assumes the mixed pixels contain two types of land cover, i.e., vegetation and soil. The sensitive parameters of Soil-Leaf-Canopy (SLC) model and a soil ratio factor were retrieved from multi-spectral data based on Look-Up Table (LUT) technology. Then, by combined with a soil ratio factor, all the parameters were input into the SLC model to simulate the surface reflectance spectrum from 400 to 2 400 nm. Taking Landsat Enhanced Thematic Mapper Plus (ETM+) image as reference image, the surface reflectance spectrum was simulated. The simulated reflectance spectrum revealed different feature information of different surface types. To test the performance of this method, the simulated reflectance spectrum was convolved with the Landsat ETM + spectral response curves and Moderate Resolution Imaging Spectrometer (MODIS) spectral response curves to obtain the simulated Landsat ETM+ and MODIS image. Finally, the simulated Landsat ETM+ and MODIS images were compared with the observed Landsat ETM+ and MODIS images. The results generally showed high correction coefficients (Landsat: 0.90-0.99, MODIS: 0.74-0.85) between most simulated bands and observed bands and indicated that the simulated reflectance spectrum was well simulated and reliable.

  15. Detection of microbial biofilms on food processing surfaces: hyperspectral fluorescence imaging study

    Science.gov (United States)

    Jun, Won; Kim, Moon S.; Chao, Kaunglin; Lefcourt, Alan M.; Roberts, Michael S.; McNaughton, James L.

    2009-05-01

    We used a portable hyperspectral fluorescence imaging system to evaluate biofilm formations on four types of food processing surface materials including stainless steel, polypropylene used for cutting boards, and household counter top materials such as formica and granite. The objective of this investigation was to determine a minimal number of spectral bands suitable to differentiate microbial biofilm formation from the four background materials typically used during food processing. Ultimately, the resultant spectral information will be used in development of handheld portable imaging devices that can be used as visual aid tools for sanitation and safety inspection (microbial contamination) of the food processing surfaces. Pathogenic E. coli O157:H7 and Salmonella cells were grown in low strength M9 minimal medium on various surfaces at 22 +/- 2 °C for 2 days for biofilm formation. Biofilm autofluorescence under UV excitation (320 to 400 nm) obtained by hyperspectral fluorescence imaging system showed broad emissions in the blue-green regions of the spectrum with emission maxima at approximately 480 nm for both E. coli O157:H7 and Salmonella biofilms. Fluorescence images at 480 nm revealed that for background materials with near-uniform fluorescence responses such as stainless steel and formica cutting board, regardless of the background intensity, biofilm formation can be distinguished. This suggested that a broad spectral band in the blue-green regions can be used for handheld imaging devices for sanitation inspection of stainless, cutting board, and formica surfaces. The non-uniform fluorescence responses of granite make distinctions between biofilm and background difficult. To further investigate potential detection of the biofilm formations on granite surfaces with multispectral approaches, principal component analysis (PCA) was performed using the hyperspectral fluorescence image data. The resultant PCA score images revealed distinct contrast between

  16. The characteristics and interpretability of land surface change and implications for project design

    Science.gov (United States)

    Sohl, Terry L.; Gallant, Alisa L.; Loveland, Thomas R.

    2004-01-01

    The need for comprehensive, accurate information on land-cover change has never been greater. While remotely sensed imagery affords the opportunity to provide information on land-cover change over large geographic expanses at a relatively low cost, the characteristics of land-surface change bring into question the suitability of many commonly used methodologies. Algorithm-based methodologies to detect change generally cannot provide the same level of accuracy as the analyses done by human interpreters. Results from the Land Cover Trends project, a cooperative venture that includes the U.S. Geological Survey, Environmental Protection Agency, and National Aeronautics and Space Administration, have shown that land-cover conversion is a relatively rare event, occurs locally in small patches, varies geographically and temporally, and is spectrally ambiguous. Based on these characteristics of change and the type of information required, manual interpretation was selected as the primary means of detecting change in the Land Cover Trends project. Mixtures of algorithm-based detection and manual interpretation may often prove to be the most feasible and appropriate design for change-detection applications. Serious examination of the expected characteristics and measurability of change must be considered during the design and implementation phase of any change analysis project.

  17. An Extension to a Filter Implementation of Local Quadratic Surface for Image Noise Estimation

    DEFF Research Database (Denmark)

    Nielsen, Allan Aasbjerg

    1999-01-01

    Based on regression analysis this paper gives a description for simple image filter design. Specifically 3x3 filter implementations of a quadratic surface, residuals from this surface, gradients and the Laplacian are given. For the residual a 5x5 filter is given also. It is shown that the 3x3......) it is concluded that if striping is to be considered as a part of the noise, the residual from a 3x3 median filter seems best. If we are interested in a salt-and-pepper noise estimator the proposed extension to the 3x3 filter for the residual from a quadratic surface seems best. Simple statistics...

  18. Seismic imaging of the upper mantle beneath the northern Central Andean Plateau: Implications for surface topography

    Science.gov (United States)

    Ward, K. M.; Zandt, G.; Beck, S. L.; Wagner, L. S.

    2015-12-01

    Extending over 1,800 km along the active South American Cordilleran margin, the Central Andean Plateau (CAP) as defined by the 3 km elevation contour is second only to the Tibetan Plateau in geographic extent. The uplift history of the 4 km high Plateau remains uncertain with paleoelevation studies along the CAP suggesting a complex, non-uniform uplift history. As part of the Central Andean Uplift and the Geodynamics of High Topography (CAUGHT) project, we use surface waves measured from ambient noise and two-plane wave tomography to image the S-wave velocity structure of the crust and upper mantle to investigate the upper mantle component of plateau uplift. We observe three main features in our S-wave velocity model including (1), a high velocity slab (2), a low velocity anomaly above the slab where the slab changes dip from near horizontal to a normal dip, and (3), a high-velocity feature in the mantle above the slab that extends along the length of the Altiplano from the base of the Moho to a depth of ~120 km with the highest velocities observed under Lake Titicaca. A strong spatial correlation exists between the lateral extent of this high-velocity feature beneath the Altiplano and the lower elevations of the Altiplano basin suggesting a potential relationship. Non-uniqueness in our seismic models preclude uniquely constraining this feature as an uppermost mantle feature bellow the Moho or as a connected eastward dipping feature extending up to 300 km in the mantle as seen in deeper mantle tomography studies. Determining if the high velocity feature represents a small lithospheric root or a delaminating lithospheric root extending ~300 km into the mantle requires more integration of observations, but either interpretation shows a strong geodynamic connection with the uppermost mantle and the current topography of the northern CAP.

  19. Digital breast tomosynthesis: computer-aided detection of clustered microcalcifications on planar projection images

    International Nuclear Information System (INIS)

    Samala, Ravi K; Chan, Heang-Ping; Lu, Yao; Hadjiiski, Lubomir M; Wei, Jun; Helvie, Mark A

    2014-01-01

    This paper describes a new approach to detect microcalcification clusters (MCs) in digital breast tomosynthesis (DBT) via its planar projection (PPJ) image. With IRB approval, two-view (cranio-caudal and mediolateral oblique views) DBTs of human subject breasts were obtained with a GE GEN2 prototype DBT system that acquires 21 projection angles spanning 60° in 3° increments. A data set of 307 volumes (154 human subjects) was divided by case into independent training (127 with MCs) and test sets (104 with MCs and 76 free of MCs). A simultaneous algebraic reconstruction technique with multiscale bilateral filtering (MSBF) regularization was used to enhance microcalcifications and suppress noise. During the MSBF regularized reconstruction, the DBT volume was separated into high frequency (HF) and low frequency components representing microcalcifications and larger structures. At the final iteration, maximum intensity projection was applied to the regularized HF volume to generate a PPJ image that contained MCs with increased contrast-to-noise ratio (CNR) and reduced search space. High CNR objects in the PPJ image were extracted and labeled as microcalcification candidates. Convolution neural network trained to recognize the image pattern of microcalcifications was used to classify the candidates into true calcifications and tissue structures and artifacts. The remaining microcalcification candidates were grouped into MCs by dynamic conditional clustering based on adaptive CNR threshold and radial distance criteria. False positive (FP) clusters were further reduced using the number of candidates in a cluster, CNR and size of microcalcification candidates. At 85% sensitivity an FP rate of 0.71 and 0.54 was achieved for view- and case-based sensitivity, respectively, compared to 2.16 and 0.85 achieved in DBT. The improvement was significant (p-value = 0.003) by JAFROC analysis. (paper)

  20. Surface topography characterization using 3D stereoscopic reconstruction of SEM images

    Science.gov (United States)

    Vedantha Krishna, Amogh; Flys, Olena; Reddy, Vijeth V.; Rosén, B. G.

    2018-06-01

    A major drawback of the optical microscope is its limitation to resolve finer details. Many microscopes have been developed to overcome the limitations set by the diffraction of visible light. The scanning electron microscope (SEM) is one such alternative: it uses electrons for imaging, which have much smaller wavelength than photons. As a result high magnification with superior image resolution can be achieved. However, SEM generates 2D images which provide limited data for surface measurements and analysis. Often many research areas require the knowledge of 3D structures as they contribute to a comprehensive understanding of microstructure by allowing effective measurements and qualitative visualization of the samples under study. For this reason, stereo photogrammetry technique is employed to convert SEM images into 3D measurable data. This paper aims to utilize a stereoscopic reconstruction technique as a reliable method for characterization of surface topography. Reconstructed results from SEM images are compared with coherence scanning interferometer (CSI) results obtained by measuring a roughness reference standard sample. This paper presents a method to select the most robust/consistent surface texture parameters that are insensitive to the uncertainties involved in the reconstruction technique itself. Results from the two-stereoscopic reconstruction algorithms are also documented in this paper.

  1. Development of a biosensor microarray towards food screening using imaging surface plasmon resonance

    NARCIS (Netherlands)

    Rebe, S.; Bremer, M.G.E.G.; Giesbers, M.; Norde, W.

    2008-01-01

    In this study we examined the possibilities of implementing direct and competitive immunoassay formats for small and large molecule detection on a microarray, using IBIS imaging surface plasmon resonance (iSPR) system. First, IBIS iSPR optics performance was evaluated. Using a glycerol calibration

  2. Development of a biosensor microarray towards food screening, using imaging surface plasmon resonance

    NARCIS (Netherlands)

    Raz, Sabina Rebe; Bremer, Maria G. E. G.; Giesbers, Marcel; Norde, Willem

    2008-01-01

    In this study we examined the possibilities of implementing direct and competitive immunoassay formats for small and large molecule detection on a microarray, using IBIS imaging surface plasmon resonance (iSPR) system. First, IBIS iSPR optics performance was evaluated. Using a glycerol calibration

  3. Imaging of Mechanical Properties of Soft Matter. From Heterogeneous Polymer Surfaces to Single Biomolecules

    NARCIS (Netherlands)

    Schön, Peter Manfred; Gosa, Maria; Vancso, Gyula J.

    2013-01-01

    In recent years the atomic force microscope (AFM) has evolved from a high resolution imaging tool to an enabling platform for physical studies at the nanoscale including quantitative mapping of mechanical characteristics of surfaces providing simultaneous topography and mechanical property maps

  4. Infrared photothermal imaging spectroscopy for detection of trace explosives on surfaces.

    Science.gov (United States)

    Kendziora, Christopher A; Furstenberg, Robert; Papantonakis, Michael; Nguyen, Viet; Byers, Jeff; Andrew McGill, R

    2015-11-01

    We are developing a technique for the standoff detection of trace explosives on relevant substrate surfaces using photothermal infrared (IR) imaging spectroscopy (PT-IRIS). This approach leverages one or more compact IR quantum cascade lasers, which are tuned to strong absorption bands in the analytes and directed to illuminate an area on a surface of interest. An IR focal plane array is used to image the surface and detect increases in thermal emission upon laser illumination. The PT-IRIS signal is processed as a hyperspectral image cube comprised of spatial, spectral, and temporal dimensions as vectors within a detection algorithm. The ability to detect trace analytes at standoff on relevant substrates is critical for security applications but is complicated by the optical and thermal analyte/substrate interactions. This manuscript describes a series of PT-IRIS experimental results and analysis for traces of RDX, TNT, ammonium nitrate, and sucrose on steel, polyethylene, glass, and painted steel panels. We demonstrate detection at surface mass loadings comparable with fingerprint depositions ( 10μg/cm2 to 100μg/cm2) from an area corresponding to a single pixel within the thermal image.

  5. Preliminary results of endorectal surface coil magnetic resonance imaging for local staging of prostate cancer

    NARCIS (Netherlands)

    Jager, G. J.; Barentsz, J. O.; de la Rosette, J. J.; Rosenbusch, G.

    1994-01-01

    To evaluate the effectiveness of endorectal surface coil (ERC) magnetic resonance imaging (MRI) in the local staging of adenocarcinoma of the prostate (ACP). A total of 23 patients who were considered candidates for radical prostatectomy because of clinically localized ACP were examined by ERC-MRI.

  6. Detection of microbial biofilms on food processing surfaces: Hyperspectral fluorescence imaging study

    Science.gov (United States)

    We used a portable hyperspectral fluorescence imaging system to evaluate biofilm formations on four types of food processing surface materials including stainless steel, polypropylene used for cutting boards, and household counter top materials such as formica and granite. The objective of this inve...

  7. Detection of organic residues on poultry processing equipment surfaces by LED-induced fluorescence imaging

    Science.gov (United States)

    Organic residues on equipment surfaces in poultry processing plants can generate cross- contamination and increase the risk of unsafe food for consumers. This research was aimed to investigate the potential of LED-induced fluorescence imaging technique for rapid inspection of stainless steel proces...

  8. Image-based rendering of intersecting surfaces for dynamic comparative visualization

    NARCIS (Netherlands)

    Busking, S.; Botha, C.P.; Ferrarini, L.; Milles, J.; Post, F.H.

    2010-01-01

    Nested or intersecting surfaces are proven techniques for visualizing shape differences between static 3D objects (Weigle and Taylor II, IEEE Visualization, Proceedings, pp. 503–510, 2005). In this paper we present an image-based formulation for these techniques that extends their use to dynamic

  9. High resolution imaging of dielectric surfaces with an evanescent field optical microscope

    NARCIS (Netherlands)

    van Hulst, N.F.; Segerink, Franciscus B.; Bölger, B.

    1992-01-01

    An evanescent field optical microscope (EFOM) is presented which employs frustrated total internal reflection o­n a localized scale by scanning a dielectric tip in close proximity to a sample surface. High resolution images of dielectric gratings and spheres containing both topographic and

  10. Rectangle Surface Coil Array in a Grid Arrangement for Resonance Imaging

    Science.gov (United States)

    2016-02-13

    magnet wires with insulating coating for rectangular surface coils. The wires are formed into four one turn 145mm x 32mm rectangular coils...switchable array, RF magnetic field, NQR, MRI, NMR, tuning, decoupling I. INTRODUCTION ESONANCE imaging can be accomplished using Nuclear Magnetic ...grid array. This achieves the switchable array configuration. Later, investigations will have circuit controlled multiplexer for switching to

  11. Kinematic behaviour of a large earthflow defined by surface displacement monitoring, DEM differencing, and ERT imaging

    Czech Academy of Sciences Publication Activity Database

    Prokešová, R.; Kardoš, M.; Tábořík, Petr; Medveďová, A.; Stacke, V.; Chudý, F.

    2014-01-01

    Roč. 224, NOV 1 (2014), s. 86-101 ISSN 0169-555X R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985891 Keywords : earthflow * surface displacement * strain modelling * DEM differencing * kinematic behaviour Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 2.577, year: 2013

  12. PROCESSING OF DIGITAL IMAGES OF INDUSTRIAL OBJECT SURFACES DURING NON-DESTRUCTIVE TESTING

    Directory of Open Access Journals (Sweden)

    A. A. Hundzin

    2016-01-01

    Full Text Available The paper presents modern approaches to processing of images obtained with the help of industrial equipment. Usage of pixel modification in small neighborhoods, application of uniform image processing while changing brightness level, possibilities for combination of several images, threshold image processing have been described in the paper. While processing a number of images on a metal structure containing micro-cracks and being under strain difference between two such images have been determined in the paper. The metal structure represents a contour specifying the difference in images. An analysis of the contour makes it possible to determine initial direction of crack propagation in the metal. A threshold binarization value has been determined while processing the image having a field of medium intensity which are disappearing in the process of simple binarization and merging with the background due to rather small drop between the edges. In this regard an algorithm of a balanced threshold histogram clipping has been selected and it is based on the following approach: two different histogram fractions are “weighed” and if one of the fractions “outweighs” then last column of the histogram fraction is removed and the procedure is repeated again. When there is rather high threshold value a contour break (disappearance of informative pixels may occur, and when there is a low threshold value – a noise (non-informative pixels may appear. The paper shows implementation of an algorithm for location of contact pads on image of semiconductor crystal. Algorithms for morphological processing of production prototype images have been obtained in the paper and these algorithms permit to detect defects on the surface of semiconductors, to carry out filtration, threshold binarization that presupposes application of an algorithm of a balanced threshold histogram clipping. The developed approaches can be used to highlight contours on the surface

  13. Amoco-US Environmental Protection Agency, pollution prevention project, Yorktown, Virginia: Surface water data

    International Nuclear Information System (INIS)

    Baloo, S.

    1991-08-01

    The report summarizes the surface water sampling program at the Amoco Refinery at Yorktown, Virginia. This was undertaken as a part of the joint project between Amoco Corporation and the United States Environmental Protection Agency to review pollution prevention alternatives at a petroleum refinery. The surface water data provides a snapshot of surface water pollutant generation and discharge from the refinery. Different process units contribute to the total wastewater flow of 460 GPM in the refinery. Water in the ditch system, which is non-process water, is free of organic contamination. Oil and grease, phenols, ammonia and sulfides are the significant components measured in the process wastewater. The concentrations of organics in most water streams leaving the individual process units are relatively low, in the 1-5 parts per million (ppm) range. A few individual streams such as the crude desalter brine and tank water draws have high pollutant loadings. Concentrations of metals in the refinery wastewater are very low. The wastewater treatment plant is very effective in reducing the pollutant loading in the water with overall removal efficiencies greater than 99% for most organics and inorganics

  14. Analysis of carotid lumen surface morphology using three-dimensional ultrasound imaging

    International Nuclear Information System (INIS)

    Chiu, Bernard; Beletsky, Vadim; Spence, J David; Parraga, Grace; Fenster, Aaron

    2009-01-01

    Carotid plaque surface irregularity and ulcerations play an important role in the risk of ischemic stroke. Ulcerated or fissured plaque, characterized by irregular surface morphology, exposes thrombogenic materials to the bloodstream, possibly leading to life- or brain-threatening thrombosis and embolization. Therefore, the quantification of plaque surface irregularity is important to identify high-risk plaques that would likely lead to vascular events. Although a number of studies have characterized plaque surface irregularity using subjective classification schemes with two or more categories, only a few have quantified surface irregularity using an objective and continuous quantity, such as Gaussian or mean curvature. In this work, our goal was to use both Gaussian and mean curvatures for identifying ulcers from 3D carotid ultrasound (US) images of human subjects. Before performing experiments using patient data, we verified the numerical accuracy of the surface curvature computation method using discrete spheres and tori with different sampling intervals. We also showed that three ulcers of the vascular phantom with 2 mm, 3 mm and 4 mm diameters were associated with high Gaussian and mean curvatures, and thus, were easily detected. Finally, we demonstrated the application of the proposed method for detecting ulcers on luminal surfaces, which were segmented from the 3D US images acquired for two human subjects.

  15. Analysis of carotid lumen surface morphology using three-dimensional ultrasound imaging

    Science.gov (United States)

    Chiu, Bernard; Beletsky, Vadim; Spence, J. David; Parraga, Grace; Fenster, Aaron

    2009-03-01

    Carotid plaque surface irregularity and ulcerations play an important role in the risk of ischemic stroke. Ulcerated or fissured plaque, characterized by irregular surface morphology, exposes thrombogenic materials to the bloodstream, possibly leading to life- or brain-threatening thrombosis and embolization. Therefore, the quantification of plaque surface irregularity is important to identify high-risk plaques that would likely lead to vascular events. Although a number of studies have characterized plaque surface irregularity using subjective classification schemes with two or more categories, only a few have quantified surface irregularity using an objective and continuous quantity, such as Gaussian or mean curvature. In this work, our goal was to use both Gaussian and mean curvatures for identifying ulcers from 3D carotid ultrasound (US) images of human subjects. Before performing experiments using patient data, we verified the numerical accuracy of the surface curvature computation method using discrete spheres and tori with different sampling intervals. We also showed that three ulcers of the vascular phantom with 2 mm, 3 mm and 4 mm diameters were associated with high Gaussian and mean curvatures, and thus, were easily detected. Finally, we demonstrated the application of the proposed method for detecting ulcers on luminal surfaces, which were segmented from the 3D US images acquired for two human subjects.

  16. Active illumination based 3D surface reconstruction and registration for image guided medialization laryngoplasty

    Science.gov (United States)

    Jin, Ge; Lee, Sang-Joon; Hahn, James K.; Bielamowicz, Steven; Mittal, Rajat; Walsh, Raymond

    2007-03-01

    The medialization laryngoplasty is a surgical procedure to improve the voice function of the patient with vocal fold paresis and paralysis. An image guided system for the medialization laryngoplasty will help the surgeons to accurately place the implant and thus reduce the failure rates of the surgery. One of the fundamental challenges in image guided system is to accurately register the preoperative radiological data to the intraoperative anatomical structure of the patient. In this paper, we present a combined surface and fiducial based registration method to register the preoperative 3D CT data to the intraoperative surface of larynx. To accurately model the exposed surface area, a structured light based stereo vision technique is used for the surface reconstruction. We combined the gray code pattern and multi-line shifting to generate the intraoperative surface of the larynx. To register the point clouds from the intraoperative stage to the preoperative 3D CT data, a shape priori based ICP method is proposed to quickly register the two surfaces. The proposed approach is capable of tracking the fiducial markers and reconstructing the surface of larynx with no damage to the anatomical structure. We used off-the-shelf digital cameras, LCD projector and rapid 3D prototyper to develop our experimental system. The final RMS error in the registration is less than 1mm.

  17. Imaging of acute injuries of the articular surfaces (chondral, osteochondral and subchondral fractures)

    Energy Technology Data Exchange (ETDEWEB)

    Bohndorf, K. [Department of Radiology, Zentralklinikum Augsburg (Germany)

    1999-10-01

    Fractures involving the articulating surfaces of bone are a common cause of chronic disability after joint injury. Acute fractures of the articular surface typically run parallel to the surface and are confined to the cartilage and/or the immediate subchondral cancellous bone. They should be distinguished from vertical or oblique bone fractures with intra-articular extension. This article reviews the mechanism of acute articular surface injuries, as well as their incidence, clinical presentation, radiologic appearance and treatment. A classification is presented based on direct inspection (arthroscopy) and imaging (especially MRI), emphasizing the distinction between lesions with intact (subchondral impaction and subchondral bone bruises) and disrupted (chondral, osteochondral lesions) cartilage. Hyaline cartilage, subchondral bone plate and subchondral cancellous bone are to be considered an anatomic unit. Subchondral articular surface lesions, osteochondral fractures and solely chondral fractures are different manifestations of impaction injuries that affect the articulating surface. Of the noninvasive imaging modalities, conventional radiography and MRI provide the most relevant information. The appropriate use of short tau inversion recovery, T1-weighted and T2-weighted (turbo) spin-echo as well as gradient-echo sequences, enables MRI to classify the various acute articular surface lesions with great accuracy and provides therapeutic guidance. (orig.)

  18. Imaging of acute injuries of the articular surfaces (chondral, osteochondral and subchondral fractures)

    International Nuclear Information System (INIS)

    Bohndorf, K.

    1999-01-01

    Fractures involving the articulating surfaces of bone are a common cause of chronic disability after joint injury. Acute fractures of the articular surface typically run parallel to the surface and are confined to the cartilage and/or the immediate subchondral cancellous bone. They should be distinguished from vertical or oblique bone fractures with intra-articular extension. This article reviews the mechanism of acute articular surface injuries, as well as their incidence, clinical presentation, radiologic appearance and treatment. A classification is presented based on direct inspection (arthroscopy) and imaging (especially MRI), emphasizing the distinction between lesions with intact (subchondral impaction and subchondral bone bruises) and disrupted (chondral, osteochondral lesions) cartilage. Hyaline cartilage, subchondral bone plate and subchondral cancellous bone are to be considered an anatomic unit. Subchondral articular surface lesions, osteochondral fractures and solely chondral fractures are different manifestations of impaction injuries that affect the articulating surface. Of the noninvasive imaging modalities, conventional radiography and MRI provide the most relevant information. The appropriate use of short tau inversion recovery, T1-weighted and T2-weighted (turbo) spin-echo as well as gradient-echo sequences, enables MRI to classify the various acute articular surface lesions with great accuracy and provides therapeutic guidance. (orig.)

  19. 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.

  20. 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)

  1. Imaging of surface spin textures on bulk crystals by scanning electron microscopy

    Science.gov (United States)

    Akamine, Hiroshi; Okumura, So; Farjami, Sahar; Murakami, Yasukazu; Nishida, Minoru

    2016-11-01

    Direct observation of magnetic microstructures is vital for advancing spintronics and other technologies. Here we report a method for imaging surface domain structures on bulk samples by scanning electron microscopy (SEM). Complex magnetic domains, referred to as the maze state in CoPt/FePt alloys, were observed at a spatial resolution of less than 100 nm by using an in-lens annular detector. The method allows for imaging almost all the domain walls in the mazy structure, whereas the visualisation of the domain walls with the classical SEM method was limited. Our method provides a simple way to analyse surface domain structures in the bulk state that can be used in combination with SEM functions such as orientation or composition analysis. Thus, the method extends applications of SEM-based magnetic imaging, and is promising for resolving various problems at the forefront of fields including physics, magnetics, materials science, engineering, and chemistry.

  2. Transference of surface markers in X-ray, CT- and MR-imaging

    International Nuclear Information System (INIS)

    Grevelhoerster, T.; Poetter, R.; Prott, F.J.; Dittrich, M.

    1995-01-01

    By using pharmacological capsules and plastic tubes filled with oily contrast medium contraining iodine (Lipiodol; Byk Gulden), marking aids were developed which can be seen in similar definite limits within the framework of MRI-, CT- and conventional X-ray-Imaging. A method to view these new, artificial markers in combination with individual, anatomical landmarks is introduced. The marking aid/surface marker, fixed on anatomical reference structures on the skin, does not result in an additional burden for the patient. The new, artificial markers are also useful for making other structures recognizable, such as anatomical relation lines, center of the portal and edges in planning imaging for radiotherapy treatments and are used as leading and reference structures to compare localisation and extent of lesions in X-ray-, CT- and MRI. Marking aids/surface markers do not have to be changed in different imaging methods. (orig./MG) [de

  3. Cabauw Experimental Results from the Project for Intercomparison of Land-Surface Parameterization Schemes.

    Science.gov (United States)

    Chen, T. H.; Henderson-Sellers, A.; Milly, P. C. D.; Pitman, A. J.; Beljaars, A. C. M.; Polcher, J.; Abramopoulos, F.; Boone, A.; Chang, S.; Chen, F.; Dai, Y.; Desborough, C. E.; Dickinson, R. E.; Dümenil, L.; Ek, M.; Garratt, J. R.; Gedney, N.; Gusev, Y. M.;  Kim, J.;  Koster, R.;  Kowalczyk, E. A.;  Laval, K.;  Lean, J.;  Lettenmaier, D.;  Liang, X.;  Mahfouf, J.-F.;  Mengelkamp, H.-T.;  Mitchell, K.;  Nasonova, O. N.;  Noilhan, J.;  Robock, A.;  Rosenzweig, C.;  Schaake, J.;  Schlosser, C. A.;  Schulz, J.-P.;  Shao, Y.;  Shmakin, A. B.;  Verseghy, D. L.;  Wetzel, P.;  Wood, E. F.;  Xue, Y.;  Yang, Z.-L.;  Zeng, Q.

    1997-06-01

    In the Project for Intercomparison of Land-Surface Parameterization Schemes phase 2a experiment, meteorological data for the year 1987 from Cabauw, the Netherlands, were used as inputs to 23 land-surface flux schemes designed for use in climate and weather models. Schemes were evaluated by comparing their outputs with long-term measurements of surface sensible heat fluxes into the atmosphere and the ground, and of upward longwave radiation and total net radiative fluxes, and also comparing them with latent heat fluxes derived from a surface energy balance. Tuning of schemes by use of the observed flux data was not permitted. On an annual basis, the predicted surface radiative temperature exhibits a range of 2 K across schemes, consistent with the range of about 10 W m2 in predicted surface net radiation. Most modeled values of monthly net radiation differ from the observations by less than the estimated maximum monthly observational error (±10 W m2). However, modeled radiative surface temperature appears to have a systematic positive bias in most schemes; this might be explained by an error in assumed emissivity and by models' neglect of canopy thermal heterogeneity. Annual means of sensible and latent heat fluxes, into which net radiation is partitioned, have ranges across schemes of30 W m2 and 25 W m2, respectively. Annual totals of evapotranspiration and runoff, into which the precipitation is partitioned, both have ranges of 315 mm. These ranges in annual heat and water fluxes were approximately halved upon exclusion of the three schemes that have no stomatal resistance under non-water-stressed conditions. Many schemes tend to underestimate latent heat flux and overestimate sensible heat flux in summer, with a reverse tendency in winter. For six schemes, root-mean-square deviations of predictions from monthly observations are less than the estimated upper bounds on observation errors (5 W m2 for sensible heat flux and 10 W m2 for latent heat flux). Actual

  4. Development of a new surface ion-source and ion guide in the ALTO project

    International Nuclear Information System (INIS)

    Cuong, P.V.

    2009-12-01

    The present work is dedicated to the ALTO project which is the production of neutron-rich gallium isotopes by the ISOL thick-target technique using photo-fission and a surface ion source. We aim at the study of the structure of 82 Ge, 83 Ge, 84 Ge via the β decay of 82 Ga, 83 Ga, and 84 Ga. We focus on the development of a new surface ion source made from materials with a high work function φ which can give high ionisation efficiencies for elements with low ionisation potentials, like alkaline as well as gallium and indium. Tungsten, rhenium and iridium are considered as good candidates for a surface ionizer because the Saha-Langmuir equation indicates high surface ionisation efficiencies for these materials. This has motivated us to equip the surface ion source at ALTO with rhenium and iridium-coated rhenium ionizer tubes of the same dimensions as the surface ion source at ISOLDE. We performed a test experiment to measure the ionisation efficiency for gallium. We also built a simulation code for the ionisation efficiency of the different surface ionisation sources (different materials and dimensions). On the other hand, for future nuclear structure studies of refractory elements such as cobalt or nickel, the ISOL technique with a thick target is no longer suitable. Indeed, the high melting point of these elements makes it difficult to volatilize and release them from a thick target. For such a situation, a technique based on thin targets is needed and the laser ion guide based on a gas cell to slow down, neutralize and stop the recoiling nuclear reaction products combined with a laser beam to re-ionize them selectively, seems a good choice. A code based on the Geant-4 tool-kit has been built to simulate the ionisation of the buffer gas. In this work, we also briefly show the results of the photo-fission yield measurements at ALTO. The fission fragments were ionized in a hot plasma ion source, mass separated and detected by germanium and scintillator detectors

  5. Pushing CHARA to its Limit: A Pathway Toward 80X80 Pixel Images of Stellar Surfaces

    Science.gov (United States)

    Norris, Ryan

    2018-04-01

    Imagine a future with 80x80 pixel images of stellar surfaces. With a maximum baseline of 330 m, the CHARA Array is already capable of achieving 0.5 mas resolution, sufficient for imaging the red supergiant Betelgeuse (d = 42.3 mas ) at such a scale. However several issues have hampered attempts to image the largest stars at CHARA, including a lack of baselines shorter than 34 m and instrument sensitivities unable to measure the faintest fringes. Here we discuss what is needed to achieve imaging of large stars at CHARA. We will present suggestions for future telescope placement, describing the advantages of a short baseline, while also considering the needs of other imaging targets that might benefit from additional baselines. We will also present developments in image reconstruction methods that can improve the resolution of images today, albeit of smaller targets and at a lesser scale. Of course, there will be example images, created using simulated oifits data and state of the art reconstruction techniques!

  6. GPU acceleration of 3D forward and backward projection using separable footprints for X-ray CT image reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meng; Fessler, Jeffrey A. [Michigan Univ., Ann Arbor, MI (United States). Dept. of Electrical Engineering and Computer Science

    2011-07-01

    Iterative 3D image reconstruction methods can improve image quality over conventional filtered back projection (FBP) in X-ray computed tomography. However, high computational costs deter the routine use of iterative reconstruction clinically. The separable footprint method for forward and back-projection simplifies the integrals over a detector cell in a way that is quite accurate and also has a relatively efficient CPU implementation. In this project, we implemented the separable footprints method for both forward and backward projection on a graphics processing unit (GPU) with NVDIA's parallel computing architecture (CUDA). This paper describes our GPU kernels for the separable footprint method and simulation results. (orig.)

  7. Cell surface expression of single chain antibodies with applications to imaging of gene expression in vivo

    International Nuclear Information System (INIS)

    Northrop, Jeffrey P.; Bednarski, Mark; Li, King C.; Barbieri, Susan O.; Lu, Amy T.; Nguyen, Dee; Varadarajan, John; Osen, Maureen; Star-Lack, Josh

    2003-01-01

    Imaging of gene expression in vivo has many potential uses for biomedical research and drug discovery, ranging from the study of gene regulation and cancer to the non-invasive assessment of gene therapies. To streamline the development of imaging marker gene technologies for nuclear medicine, we propose a new approach to the design of reporter/probe pairs wherein the reporter is a cell surface-expressed single chain antibody variable fragment that has been raised against a low molecular weight imaging probe with optimized pharmacokinetic properties. Proof of concept of the approach was achieved using a single chain antibody variable fragment that binds with high affinity to fluorescein and an imaging probe consisting of fluorescein isothiocyanate coupled to the chelator diethylene triamine penta-acetic acid labeled with the gamma-emitter 111 In. We demonstrate specific high-affinity binding of this probe to the cell surface-expressed reporter in vitro and assess the in vivo biodistribution of the probe both in wild-type mice and in mice harboring tumor xenografts expressing the reporter. Specific uptake of the probe by, and in vivo imaging of, tumors expressing the reporter are shown. Since ScFvs with high affinities can be raised to almost any protein or small molecule, the proposed methodology may offer a new flexibility in the design of imaging tracer/reporter pairs wherein both probe pharmacokinetics and binding affinities can be readily optimized. (orig.)

  8. The artificial object detection and current velocity measurement using SAR ocean surface images

    Science.gov (United States)

    Alpatov, Boris; Strotov, Valery; Ershov, Maksim; Muraviev, Vadim; Feldman, Alexander; Smirnov, Sergey

    2017-10-01

    Due to the fact that water surface covers wide areas, remote sensing is the most appropriate way of getting information about ocean environment for vessel tracking, security purposes, ecological studies and others. Processing of synthetic aperture radar (SAR) images is extensively used for control and monitoring of the ocean surface. Image data can be acquired from Earth observation satellites, such as TerraSAR-X, ERS, and COSMO-SkyMed. Thus, SAR image processing can be used to solve many problems arising in this field of research. This paper discusses some of them including ship detection, oil pollution control and ocean currents mapping. Due to complexity of the problem several specialized algorithm are necessary to develop. The oil spill detection algorithm consists of the following main steps: image preprocessing, detection of dark areas, parameter extraction and classification. The ship detection algorithm consists of the following main steps: prescreening, land masking, image segmentation combined with parameter measurement, ship orientation estimation and object discrimination. The proposed approach to ocean currents mapping is based on Doppler's law. The results of computer modeling on real SAR images are presented. Based on these results it is concluded that the proposed approaches can be used in maritime applications.

  9. 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

  10. 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.

  11. Surface imaging, portal imaging, and skin marker set-up vs. CBCT for radiotherapy of the thorax and pelvis

    International Nuclear Information System (INIS)

    Pallotta, Stefania; Bucciolini, Marta; Vanzi, Eleonora; Marrazzo, Livia; Simontacchi, Gabriele; Paiar, Fabiola; Ceroti, Marco; Livi, Lorenzo

    2015-01-01

    The aim of this study was to compare surface imaging, portal imaging, and skin marker set-up in radiotherapy of thoracic and pelvic regions, using cone beam computed tomography (CBCT) data as the gold standard. Twenty patients were included in this study. CBCT, surface acquisition (SA), and two orthogonal portal images (PI) were acquired during the first four treatment sessions. Patient set-up corrections, obtained by registering the planning CT with CBCT, were used as the gold standard. Registration results of the PI and SA were evaluated and compared with those obtained with CBCT. The advantage derived from using SA or PI verification systems over a skin marker set-up was also quantified. A statistically significant difference between PI and SA (in favour of PI) was observed in seven patients undergoing treatment of the pelvic region and in two patients undergoing treatment of the thoracic region. The use of SA or PI, compared with a skin marker set-up, improved patient positioning in 50% and 57 % of the thoracic fractions, respectively. For pelvic fractions, the use of PI was beneficial in 73 % of the cases, while the use of SA was beneficial in only 45 %. Patient positioning worsened with SA, particularly along longitudinal and vertical directions. PI yielded more accurate registration results than SA for both pelvic and thoracic fractions. Compared with the skin marker set-up, PI performances were superior to SA for pelvic fractions while comparable results were obtained for thoracic fractions. (orig.) [de

  12. Exploring the Leishmania Hydrophilic Acylated Surface Protein B (HASPB) Export Pathway by Live Cell Imaging Methods.

    Science.gov (United States)

    MacLean, Lorna; Price, Helen; O'Toole, Peter

    2016-01-01

    Leishmania major is a human-infective protozoan parasite transmitted by the bite of the female phlebotomine sand fly. The L. major hydrophilic acylated surface protein B (HASPB) is only expressed in infective parasite stages suggesting a role in parasite virulence. HASPB is a "nonclassically" secreted protein that lacks a conventional signal peptide, reaching the cell surface by an alternative route to the classical ER-Golgi pathway. Instead HASPB trafficking to and exposure on the parasite plasma membrane requires dual N-terminal acylation. Here, we use live cell imaging methods to further explore this pathway allowing visualization of key events in real time at the individual cell level. These methods include live cell imaging using fluorescent reporters to determine the subcellular localization of wild type and acylation site mutation HASPB18-GFP fusion proteins, fluorescence recovery after photobleaching (FRAP) to analyze the dynamics of HASPB in live cells, and live antibody staining to detect surface exposure of HASPB by confocal microscopy.

  13. Surface-functionalized nanoparticles for biosensing and imaging-guided therapeutics

    Science.gov (United States)

    Jiang, Shan; Win, Khin Yin; Liu, Shuhua; Teng, Choon Peng; Zheng, Yuangang; Han, Ming-Yong

    2013-03-01

    In this article, the very recent progress of various functional inorganic nanomaterials is reviewed including their unique properties, surface functionalization strategies, and applications in biosensing and imaging-guided therapeutics. The proper surface functionalization renders them with stability, biocompatibility and functionality in physiological environments, and further enables their targeted use in bioapplications after bioconjugation via selective and specific recognition. The surface-functionalized nanoprobes using the most actively studied nanoparticles (i.e., gold nanoparticles, quantum dots, upconversion nanoparticles, and magnetic nanoparticles) make them an excellent platform for a wide range of bioapplications. With more efforts in recent years, they have been widely developed as labeling probes to detect various biological species such as proteins, nucleic acids and ions, and extensively employed as imaging probes to guide therapeutics such as drug/gene delivery and photothermal/photodynamic therapy.

  14. FPGA based image processing for optical surface inspection with real time constraints

    Science.gov (United States)

    Hasani, Ylber; Bodenstorfer, Ernst; Brodersen, Jörg; Mayer, Konrad J.

    2015-02-01

    Today, high-quality printing products like banknotes, stamps, or vouchers, are automatically checked by optical surface inspection systems. In a typical optical surface inspection system, several digital cameras acquire the printing products with fine resolution from different viewing angles and at multiple wavelengths of the visible and also near infrared spectrum of light. The cameras deliver data streams with a huge amount of image data that have to be processed by an image processing system in real time. Due to the printing industry's demand for higher throughput together with the necessity to check finer details of the print and its security features, the data rates to be processed tend to explode. In this contribution, a solution is proposed, where the image processing load is distributed between FPGAs and digital signal processors (DSPs) in such a way that the strengths of both technologies can be exploited. The focus lies upon the implementation of image processing algorithms in an FPGA and its advantages. In the presented application, FPGAbased image-preprocessing enables real-time implementation of an optical color surface inspection system with a spatial resolution of 100 μm and for object speeds over 10 m/s. For the implementation of image processing algorithms in the FPGA, pipeline parallelism with clock frequencies up to 150 MHz together with spatial parallelism based on multiple instantiations of modules for parallel processing of multiple data streams are exploited for the processing of image data of two cameras and three color channels. Due to their flexibility and their fast response times, it is shown that FPGAs are ideally suited for realizing a configurable all-digital PLL for the processing of camera line-trigger signals with frequencies about 100 kHz, using pure synchronous digital circuit design.

  15. Development and comparison of projection and image space 3D nodule insertion techniques

    Science.gov (United States)

    Robins, Marthony; Solomon, Justin; Sahbaee, Pooyan; Samei, Ehsan

    2016-04-01

    This study aimed to develop and compare two methods of inserting computerized virtual lesions into CT datasets. 24 physical (synthetic) nodules of three sizes and four morphologies were inserted into an anthropomorphic chest phantom (LUNGMAN, KYOTO KAGAKU). The phantom was scanned (Somatom Definition Flash, Siemens Healthcare) with and without nodules present, and images were reconstructed with filtered back projection and iterative reconstruction (SAFIRE) at 0.6 mm slice thickness using a standard thoracic CT protocol at multiple dose settings. Virtual 3D CAD models based on the physical nodules were virtually inserted (accounting for the system MTF) into the nodule-free CT data using two techniques. These techniques include projection-based and image-based insertion. Nodule volumes were estimated using a commercial segmentation tool (iNtuition, TeraRecon, Inc.). Differences were tested using paired t-tests and R2 goodness of fit between the virtually and physically inserted nodules. Both insertion techniques resulted in nodule volumes very similar to the real nodules (values were all <0.97 for both insertion techniques. These data imply that these techniques can confidently be used as a means of inserting virtual nodules in CT datasets. These techniques can be instrumental in building hybrid CT datasets composed of patient images with virtually inserted nodules.

  16. 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.

  17. 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.

  18. Automatic segmentation of rotational x-ray images for anatomic intra-procedural surface generation in atrial fibrillation ablation procedures.

    Science.gov (United States)

    Manzke, Robert; Meyer, Carsten; Ecabert, Olivier; Peters, Jochen; Noordhoek, Niels J; Thiagalingam, Aravinda; Reddy, Vivek Y; Chan, Raymond C; Weese, Jürgen

    2010-02-01

    Since the introduction of 3-D rotational X-ray imaging, protocols for 3-D rotational coronary artery imaging have become widely available in routine clinical practice. Intra-procedural cardiac imaging in a computed tomography (CT)-like fashion has been particularly compelling due to the reduction of clinical overhead and ability to characterize anatomy at the time of intervention. We previously introduced a clinically feasible approach for imaging the left atrium and pulmonary veins (LAPVs) with short contrast bolus injections and scan times of approximately 4 -10 s. The resulting data have sufficient image quality for intra-procedural use during electro-anatomic mapping (EAM) and interventional guidance in atrial fibrillation (AF) ablation procedures. In this paper, we present a novel technique to intra-procedural surface generation which integrates fully-automated segmentation of the LAPVs for guidance in AF ablation interventions. Contrast-enhanced rotational X-ray angiography (3-D RA) acquisitions in combination with filtered-back-projection-based reconstruction allows for volumetric interrogation of LAPV anatomy in near-real-time. An automatic model-based segmentation algorithm allows for fast and accurate LAPV mesh generation despite the challenges posed by image quality; relative to pre-procedural cardiac CT/MR, 3-D RA images suffer from more artifacts and reduced signal-to-noise. We validate our integrated method by comparing 1) automatic and manual segmentations of intra-procedural 3-D RA data, 2) automatic segmentations of intra-procedural 3-D RA and pre-procedural CT/MR data, and 3) intra-procedural EAM point cloud data with automatic segmentations of 3-D RA and CT/MR data. Our validation results for automatically segmented intra-procedural 3-D RA data show average segmentation errors of 1) approximately 1.3 mm compared with manual 3-D RA segmentations 2) approximately 2.3 mm compared with automatic segmentation of pre-procedural CT/MR data and 3

  19. ESTIMATION OF SHIE GLACIER SURFACE MOVEMENT USING OFFSET TRACKING TECHNIQUE WITH COSMO-SKYMED IMAGES

    Directory of Open Access Journals (Sweden)

    Q. Wang

    2017-09-01

    Full Text Available Movement is one of the most important characteristics of glaciers which can cause serious natural disasters. For this reason, monitoring this massive blocks is a crucial task. Synthetic Aperture Radar (SAR can operate all day in any weather conditions and the images acquired by SAR contain intensity and phase information, which are irreplaceable advantages in monitoring the surface movement of glaciers. Moreover, a variety of techniques like DInSAR and offset tracking, based on the information of SAR images, could be applied to measure the movement. Sangwang lake, a glacial lake in the Himalayas, has great potentially danger of outburst. Shie glacier is situated at the upstream of the Sangwang lake. Hence, it is significant to monitor Shie glacier surface movement to assess the risk of outburst. In this paper, 6 high resolution COSMO-SkyMed images spanning from August to December, 2016 are applied with offset tracking technique to estimate the surface movement of Shie glacier. The maximum velocity of Shie glacier surface movement is 51 cm/d, which was observed at the end of glacier tongue, and the velocity is correlated with the change of elevation. Moreover, the glacier surface movement in summer is faster than in winter and the velocity decreases as the local temperature decreases. Based on the above conclusions, the glacier may break off at the end of tongue in the near future. The movement results extracted in this paper also illustrate the advantages of high resolution SAR images in monitoring the surface movement of small glaciers.

  20. Data Qualification Report: Precipitation and Surface Geology Data for Use on the Yucca Mountain Project

    International Nuclear Information System (INIS)

    C. Wilson

    2000-01-01

    The unqualified data addressed in this qualification report have been cited in an Analysis Model Report (AMR) to support the Site Recommendation in determining the suitability of Yucca Mountain as a repository for high-level radioactive waste. The unqualified data include precipitation volumes and surface geology maps The precipitation data consist of daily precipitation volumes measured at Yucca Mountain. The surface geology data include identification of the types and surface expressions of geologic units and associated structural features such as faults. These data were directly used in AMR U0010, Simulation of Net Infiltration for Modern and Potential Future Climates, ANL-NBS-HS-000032 (Hevesi et al. 2000), to estimate net infiltration into Yucca Mountain. This report evaluates the unqualified data within the context of supporting studies of this type for the Yucca Mountain Site Characterization Project (YMP). The purpose of this report is to identify data that can be cited as qualified for use in technical products to support the YMP Site Recommendation and that may also be used to support the License Application. The qualified data may either be retained in the original Data Tracking Number (DTN) or placed in new DTNs generated as a result of the evaluation. The appropriateness and limitations (if any) of the data with respect to intended use are addressed in this report. In accordance with Attachment 1 of procedure AP-3.15Q, Rev. 02, Managing Technical Product Inputs, it has been determined that the unqualified precipitation and surface geology data are not used in the direct calculation of Principal Factors for postclosure safety or disruptive events. References to tables, figures, and sections from Hevesi et al. (2000) are based on Rev. 00 of that document

  1. Determination of the fractal dimension surface of the fracture from SEM images with assistance of the computer image quantitative analysis system

    International Nuclear Information System (INIS)

    Wawszczak, J.

    1999-01-01

    This paper presents a procedure for quantitative image analysis for determination of the fractal dimension from SEM surface images of the fracture 0H14N5CuNb steel. Investigated quenched and tempered samples of the steel after impact tests (in room and -85 o C temperatures). This method can be useful for analysing local fractal dimension of any surface parts (not oriented) of the fracture with different topography of this surface. (author)

  2. Radioactivity distribution measurement of various natural material surfaces with imaging plate

    International Nuclear Information System (INIS)

    Mori, C.; Suzuki, T.; Koido, S.; Uritani, A.; Yanagida, K.; Wu, Y.; Nishizawa, K.

    1996-01-01

    Distribution images of natural radioactivity in natural materials such as vegetables were obtained by using Imaging Platc. In ssuch cases, it is necessary to reduce background radiation intensity by one order or more. Graded shielding is very important. Espacially, the innermost surface of a shielding box sshould be covered with acrylic rein plate. We obtained natural radioactivity distribution images of vegetable, sea food, mea etc. Most β-rays emitted from 40 K print the radioactivity distribution image. Comparison between γ-ray intensity of KCL solution measured with HPGe detector and that of natural material specimen gave the radioactivity around 0.06- 0.04Bq/g depending on the kind and the part of specimens. (author). 6 refs., 5 figs., 1 tab

  3. Micro patterned surfaces: an effective tool for long term digital holographic microscopy cell imaging

    Science.gov (United States)

    Mues, Sarah; Lilge, Inga; Schönherr, Holger; Kemper, Björn; Schnekenburger, Jürgen

    2017-02-01

    The major problem of Digital Holographic Microscopy (DHM) long term live cell imaging is that over time most of the tracked cells move out of the image area and other ones move in. Therefore, most of the cells are lost for the evaluation of individual cellular processes. Here, we present an effective solution for this crucial problem of long-term microscopic live cell analysis. We have generated functionalized slides containing areas of 250 μm per 200 μm. These micropatterned biointerfaces consist of passivating polyaclrylamide brushes (PAAm). Inner areas are backfilled with octadecanthiol (ODT), which allows cell attachment. The fouling properties of these surfaces are highly controllable and therefore the defined areas designed for the size our microscopic image areas were effective in keeping all cells inside the rectangles over the selected imaging period.

  4. Quadrature Slotted Surface Coil Pair for Magnetic Resonance Imaging at 4 Tesla: Phantom Study

    Directory of Open Access Journals (Sweden)

    Solis S.E.

    2012-01-01

    Full Text Available A coil array was composed of two slotted surface coils forming a structure with two plates at 900, each one having 6 circular slots and is introduced in this paper. Numerical simulations of the magnetic field of this coil array were performed at 170 MHz using the finite element method to study its behaviour. This coil array was developed for brain magnetic resonance imaging to be operated at the resonant frequency of 170 MHz in the transceiver mode and quadrature driven. Numerical simulations demonstrated that electromagnetic interaction between the coil elements is negligible, and that the magnetic field showed a good uniformity. Phantom images were acquired with our coil array and standard pulse sequences on a research-dedicated 4 Tesla scanner. In vitro images showed the feasibility of this coil array for standard pulses and high field magnetic resonance imaging.

  5. Research of state of metal welded joint by deformation and corrosion surface projection parameters

    Directory of Open Access Journals (Sweden)

    Demchenko Maria Vyacheslavovna

    2017-10-01

    Full Text Available At industrial enterprises in building structures and equipment one can see corrosion damage, as well as damage accumulated during operation period. The areas of stress concentration are welded joints as their structure is heterogeneous. From the point of view of the scale hierarchy, the welded joint represents the welded and base metal zones at the meso-macrolevel, the weld zone, the thermal zone, the base metal at the micro-mesolevel, the grain constituents at the nano-microlevel. Borders are the stress concentrators at different scale levels, thus they becomes the most dangerous places of metal structure. Modeling by the molecular dynamics method at the atomic level has shown nanocracks initiation in triple junctions of grain boundaries and on the ledges of the grain boundaries. Due to active development of nanotechnology, it became possible to evaluate the state of the weld metal at the nanoscale, where irreversible changes take place from the very beginning. Existing methods of nondestructive testing can detect damage only at the meso- and macrolevel. Modern equipment makes it possible to use other methods of control and approaches. For example, according to GOST R55046-2012 and R57223-2016, the analysis of the parameters of the surface projection deformation performed by confocal laser scanning microscopy should be taken into account when the evaluation of state of metal pipelines is carried out. However, there is a problem to monitore it due to various factors affecting the surface during operation. The paper proposes an additional method to estimate the state of weld metal at any stage of deformation that uses 3D analysis of the parameters of the «artificial» corrosion relief of surface. During the operation period changes in the stress-strain state and structure of the metal take place, as the result the character and depth of etching of the grains of the structural components and their boundaries change too. Evaluation of the

  6. Horonobe Underground Research Laboratory Project. Plans for surface-based investigations. Phase 1

    International Nuclear Information System (INIS)

    Goto, Junichi; Hama, Katsuhiro

    2003-10-01

    The Horonobe Underground Research Laboratory Project is an investigation project which is planned over 20 years. The investigations are conducted in the three phases: investigations from surface (Phase 1), investigations during construction of the underground facility (Phase 2) and investigations using the facility (Phase 3). Taking into account the results from 'H12: Project of Establish the Scientific and Technical Basis for HLW Disposal in Japan - Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan-' (JNC, 2000), research and development goals for the Horonobe URL project were re-defined as follows; a) Development of investigation technologies for the geological environment, b) Development of monitoring technologies for the geological environment, c) Study on the long-term stability of the geological environment, d) Development of the basis for engineering technologies in deep underground, e) Verification of technologies for engineered barriers, f) Development of detailed designing technologies of the repositories, and g) Improvement of safety assessment methodologies. Investigations for the goals a) to d) and e) to g) are conducted in the 'Geoscientific Research' and 'Research and Development on Geological Disposal', respectively. In Phase 1, a 'laboratory construction area' of a few kilometers square is selected based on the results from early stage investigations. Subsequent investigations are concentrated in the selected area and its periphery. Acquisition of data by surface-based investigations, modeling of the geological environment and predictions of changes in the geological environment caused by the construction of the underground facility, are conducted in a) Development of investigation technologies for the geological environment. Development and installation of monitoring equipments and data acquisition prior to the construction of the underground facility fall under b) Development of monitoring technologies

  7. AFM imaging and analysis of local mechanical properties for detection of surface pattern of functional groups

    Energy Technology Data Exchange (ETDEWEB)

    Knotek, Petr, E-mail: petr.knotek@upce.cz [University of Pardubice, Faculty of Chemical Technology, Joint Laboratory of Solid State Chemistry of IMC ASCR and University of Pardubice, Studentska 573, 532 10 Pardubice (Czech Republic); Chanova, Eliska; Rypacek, Frantisek [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovskeho sq. 2, 162 06 Prague (Czech Republic)

    2013-05-01

    In this work we evaluate the applicability of different atomic force microscopy (AFM) modes, such as Phase Shift Imaging, Atomic Force Acoustic Microscopy (AFAM) and Force Spectroscopy, for mapping of the distribution pattern of low-molecular-weight biomimetic groups on polymer biomaterial surfaces. Patterns with either random or clustered spatial distribution of bioactive peptide group derived from fibronectin were prepared by surface deposition of functional block copolymer nano-colloids and grafted with RGDS peptide containing the sequence of amino acids arginine–glycine–aspartic acid–serine (conventionally labeled as RGDS) and carrying biotin as a tag. The biotin-tagged peptides were labeled with 40 nm streptavidin-modified Au nanospheres. The peptide molecules were localized through the detection of bound Au nanospheres by AFM, and thus, the surface distribution of peptides was revealed. AFM techniques capable of monitoring local mechanical properties of the surface were proved to be the most efficient for identification of Au nano-markers. The efficiency was successfully demonstrated on two different patterns, i.e. random and clustered distribution of RGDS peptides on structured surface of the polymer biomaterial. Highlights: ► Bioactive peptides for cell adhesion on PLA-b-PEO biomimetic surface were visualized. ► The biotin-tagged RGDS peptides were labeled with streptavidin-Au nanospheres. ► The RGDS pattern was detected using different atomic force microscopy (AFM) modes. ► Phase Shift Image was proved to be suitable method for studying peptide distribution.

  8. Public financing of research projects in Poland – its image and consequences?

    Directory of Open Access Journals (Sweden)

    Feldy Marzena

    2016-12-01

    Full Text Available Both the size of appropriation as well as their distribution have had a profound impact on the shape and activities of the science sector. The creation of a fair system of distribution of public resources to research that will also facilitate the effective implementation of the pursued scientific policy goals represents a major challenge. The issue of the determination of the right proportions of individual distribution channels remains critical. Despite this task being the responsibility of the State, establishing cooperation in this respect with the scientific community is desirable. The implementation of solutions that raise the concerns of scientists leads to system instability and reduced effectiveness which is manifest among others in a lower level of indicators of scientific excellence and innovation in the country. These observations are pertinent to Poland where the manner in which scientific institutes operate were changed under the 2009–2011 reform. A neoliberal operating model based on competitiveness and rewarding of top rated scientific establishments and scientists was implemented. In light of these facts, the initiation of research that will provide information on how the implemented changes are perceived by the scientific community seems to be appropriate. The aim of this article is in particlar presenting how the project model of financing laid down under the reform is perceived and what kind of image has been shaped among Polish scientists. In order to gain a comprehensive picture of the situation, both the rational and emotional image was subject to analysis. The conclusions regarding the perception of the project model were drawn on the basis of empirical materials collected in a qualitative study the specifics of which will be presented in the chapter on methodology. Prior to that, the author discusses the basic models for the distribution of state support for science and characterises the most salient features of the

  9. Detection of fecal contamination on beef meat surfaces using handheld fluorescence imaging device (HFID)

    Science.gov (United States)

    Oh, Mirae; Lee, Hoonsoo; Cho, Hyunjeong; Moon, Sang-Ho; Kim, Eun-Kyung; Kim, Moon S.

    2016-05-01

    Current meat inspection in slaughter plants, for food safety and quality attributes including potential fecal contamination, is conducted through by visual examination human inspectors. A handheld fluorescence-based imaging device (HFID) was developed to be an assistive tool for human inspectors by highlighting contaminated food and food contact surfaces on a display monitor. It can be used under ambient lighting conditions in food processing plants. Critical components of the imaging device includes four 405-nm 10-W LEDs for fluorescence excitation, a charge-coupled device (CCD) camera, optical filter (670 nm used for this study), and Wi-Fi transmitter for broadcasting real-time video/images to monitoring devices such as smartphone and tablet. This study aimed to investigate the effectiveness of HFID in enhancing visual detection of fecal contamination on red meat, fat, and bone surfaces of beef under varying ambient luminous intensities (0, 10, 30, 50 and 70 foot-candles). Overall, diluted feces on fat, red meat and bone areas of beef surfaces were detectable in the 670-nm single-band fluorescence images when using the HFID under 0 to 50 foot-candle ambient lighting.

  10. Segmentation of 3D ultrasound computer tomography reflection images using edge detection and surface fitting

    Science.gov (United States)

    Hopp, T.; Zapf, M.; Ruiter, N. V.

    2014-03-01

    An essential processing step for comparison of Ultrasound Computer Tomography images to other modalities, as well as for the use in further image processing, is to segment the breast from the background. In this work we present a (semi-) automated 3D segmentation method which is based on the detection of the breast boundary in coronal slice images and a subsequent surface fitting. The method was evaluated using a software phantom and in-vivo data. The fully automatically processed phantom results showed that a segmentation of approx. 10% of the slices of a dataset is sufficient to recover the overall breast shape. Application to 16 in-vivo datasets was performed successfully using semi-automated processing, i.e. using a graphical user interface for manual corrections of the automated breast boundary detection. The processing time for the segmentation of an in-vivo dataset could be significantly reduced by a factor of four compared to a fully manual segmentation. Comparison to manually segmented images identified a smoother surface for the semi-automated segmentation with an average of 11% of differing voxels and an average surface deviation of 2mm. Limitations of the edge detection may be overcome by future updates of the KIT USCT system, allowing a fully-automated usage of our segmentation approach.

  11. Implementation of a high-resolution workstation for primary diagnosis of projection radiography images

    Science.gov (United States)

    Good, Walter F.; Herron, John M.; Maitz, Glenn S.; Gur, David; Miller, Stephen L.; Straub, William H.; Fuhrman, Carl R.

    1990-08-01

    We designed and implemented a high-resolution video workstation as the central hardware component in a comprehensive multi-project program comparing the use of digital and film modalities. The workstation utilizes a 1.8 GByte real-time disk (RCI) capable of storing 400 full-resolution images and two Tektronix (GMA251) display controllers with 19" monitors (GMA2O2). The display is configured in a portrait format with a resolution of 1536 x 2048 x 8 bit, and operates at 75 Hz in a noninterlaced mode. Transmission of data through a 12 to 8 bit lookup table into the display controllers occurs at 20 MBytes/second (.35 seconds per image). The workstation allows easy use of brightness (level) and contrast (window) to be manipulated with a trackball, and various processing options can be selected using push buttons. Display of any of the 400 images is also performed at 20MBytes/sec (.35 sec/image). A separate text display provides for the automatic display of patient history data and for a scoring form through which readers can interact with the system by means of a computer mouse. In addition, the workstation provides for the randomization of cases and for the immediate entry of diagnostic responses into a master database. Over the past year this workstation has been used for over 10,000 readings in diagnostic studies related to 1) image resolution; 2) film vs. soft display; 3) incorporation of patient history data into the reading process; and 4) usefulness of image processing.

  12. 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...

  13. 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.

  14. 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

  15. What spatial scales are believable for climate model projections of sea surface temperature?

    Science.gov (United States)

    Kwiatkowski, Lester; Halloran, Paul R.; Mumby, Peter J.; Stephenson, David B.

    2014-09-01

    Earth system models (ESMs) provide high resolution simulations of variables such as sea surface temperature (SST) that are often used in off-line biological impact models. Coral reef modellers have used such model outputs extensively to project both regional and global changes to coral growth and bleaching frequency. We assess model skill at capturing sub-regional climatologies and patterns of historical warming. This study uses an established wavelet-based spatial comparison technique to assess the skill of the coupled model intercomparison project phase 5 models to capture spatial SST patterns in coral regions. We show that models typically have medium to high skill at capturing climatological spatial patterns of SSTs within key coral regions, with model skill typically improving at larger spatial scales (≥4°). However models have much lower skill at modelling historical warming patters and are shown to often perform no better than chance at regional scales (e.g. Southeast Asian) and worse than chance at finer scales (coral bleaching frequency and other marine processes linked to SST warming.

  16. THE EUROSDR PROJECT "RADIOMETRIC ASPECTS OF DIGITAL PHOTOGRAMMETRIC IMAGES" – RESULTS OF THE EMPIRICAL PHASE

    Directory of Open Access Journals (Sweden)

    E. Honkavaara

    2012-09-01

    Full Text Available This article presents the empirical research carried out in the context of the multi-site EuroSDR project "Radiometric aspects of digital photogrammetric images" and provides highlights of the results. The investigations have considered the vicarious radiometric and spatial resolution validation and calibration of the sensor system, radiometric processing of the image blocks either by performing relative radiometric block equalization or into absolutely reflectance calibrated products, and finally aspects of practical applications on NDVI layer generation and tree species classification. The data sets were provided by Leica Geosystems ADS40 and Intergraph DMC and the participants represented stakeholders in National Mapping Authorities, software development and research. The investigations proved the stability and quality of evaluated imaging systems with respect to radiometry and optical system. The first new-generation methods for reflectance calibration and equalization of photogrammetric image block data provided promising accuracy and were also functional from the productivity and usability points of view. The reflectance calibration methods provided up to 5% accuracy without any ground reference. Application oriented results indicated that automatic interpretation methods will benefit from the optimal use of radiometrically accurate multi-view photogrammetric imagery.

  17. Strain Imaging of Nanoscale Semiconductor Heterostructures with X-Ray Bragg Projection Ptychography

    Science.gov (United States)

    Holt, Martin V.; Hruszkewycz, Stephan O.; Murray, Conal E.; Holt, Judson R.; Paskiewicz, Deborah M.; Fuoss, Paul H.

    2014-04-01

    We report the imaging of nanoscale distributions of lattice strain and rotation in complementary components of lithographically engineered epitaxial thin film semiconductor heterostructures using synchrotron x-ray Bragg projection ptychography (BPP). We introduce a new analysis method that enables lattice rotation and out-of-plane strain to be determined independently from a single BPP phase reconstruction, and we apply it to two laterally adjacent, multiaxially stressed materials in a prototype channel device. These results quantitatively agree with mechanical modeling and demonstrate the ability of BPP to map out-of-plane lattice dilatation, a parameter critical to the performance of electronic materials.

  18. 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.

  19. High-resolution imaging of cellular processes across textured surfaces using an indexed-matched elastomer.

    Science.gov (United States)

    Ravasio, Andrea; Vaishnavi, Sree; Ladoux, Benoit; Viasnoff, Virgile

    2015-03-01

    Understanding and controlling how cells interact with the microenvironment has emerged as a prominent field in bioengineering, stem cell research and in the development of the next generation of in vitro assays as well as organs on a chip. Changing the local rheology or the nanotextured surface of substrates has proved an efficient approach to improve cell lineage differentiation, to control cell migration properties and to understand environmental sensing processes. However, introducing substrate surface textures often alters the ability to image cells with high precision, compromising our understanding of molecular mechanisms at stake in environmental sensing. In this paper, we demonstrate how nano/microstructured surfaces can be molded from an elastomeric material with a refractive index matched to the cell culture medium. Once made biocompatible, contrast imaging (differential interference contrast, phase contrast) and high-resolution fluorescence imaging of subcellular structures can be implemented through the textured surface using an inverted microscope. Simultaneous traction force measurements by micropost deflection were also performed, demonstrating the potential of our approach to study cell-environment interactions, sensing processes and cellular force generation with unprecedented resolution. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. Study on municipal road cracking and surface deformation based on image recognition

    Science.gov (United States)

    Yuan, Haitao; Wang, Shuai; Tan, Jizong

    2017-05-01

    In recent years, the digital image recognition technology of concrete structure cracks and deformation of binocular vision technology detection of civil engineering structure have made substantial development. As a result, people's understanding of the road engineering structure cracking and surface deformation recognition gives rise to a new situation. For the research on digital image concrete structure cracking and masonry structure surface deformation recognition technology, the key is to break through in the method, and to improve the traditional recognition technology and mode. Only in this way can we continuously improve the security level of the highway, to adapt to the new requirements of the development of new urbanization and modernization. This thesis focuses on and systematically analyzes the digital image road engineering structure cracking and key technologies of surface deformation recognition and its engineering applications. In addition, we change the concrete structure cracking and masonry structure surface deformation recognition pattern, and realize the breakthrough and innovation of the road structure safety testing means and methods.

  1. Imaging surface nanobubbles at graphite–water interfaces with different atomic force microscopy modes

    International Nuclear Information System (INIS)

    Yang, Chih-Wen; Lu, Yi-Hsien; Hwang, Ing-Shouh

    2013-01-01

    We have imaged nanobubbles on highly ordered pyrolytic graphite (HOPG) surfaces in pure water with different atomic force microscopy (AFM) modes, including the frequency-modulation, the tapping, and the PeakForce techniques. We have compared the performance of these modes in obtaining the surface profiles of nanobubbles. The frequency-modulation mode yields a larger height value than the other two modes and can provide more accurate measurement of the surface profiles of nanobubbles. Imaging with PeakForce mode shows that a nanobubble appears smaller and shorter with increasing peak force and disappears above a certain peak force, but the size returns to the original value when the peak force is reduced. This indicates that imaging with high peak forces does not cause gas removal from the nanobubbles. Based on the presented findings and previous AFM observations, the existing models for nanobubbles are reviewed and discussed. The model of gas aggregate inside nanobubbles provides a better explanation for the puzzles of the high stability and the contact angle of surface nanobubbles. (paper)

  2. Some key techniques of SPOT-5 image processing in new national land and resources investigation project

    Science.gov (United States)

    Xue, Changsheng; Li, Qingquan; Li, Deren

    2004-02-01

    In 1988, the detail information on land resource was investigated in China. Fourteen years later, it has changed a lot. It is necessary that the second land resource detailed investigation should be implemented. On this condition, the New National Land and Resources Investigation Project in China, which will last 12 years, has been started since 1999. The project is directly under the administration of the Ministry of Land and Resource (MLR). It was organized and implemented By China Geological, China Land Surveying and Planning Institute (CLSPI) and Information Center of MLR. It is a grand and cross century project supported by the Central Finance, based on State and public interests and strategic characteristics. Up to now, "Land Use Dynamic Monitoring By Remote Sensing," "Arable Land Resource Investigation," "Rural Collective Land Property Right Investgiation," "Establishment of Public Consulting Standardization of Cadastral Information," "Land Resource Fundamental Maps and Data Updating," "Urban Land Price Investigation and Intensive Utilization Potential Capacity Evaluation," "Farmland Classification, Gradation, and Evaluation," "Land Use Database Construction at City or County Level" 8 subprojects have had the preliminary achievements. In this project, SPOT-1/2/4 and Landsat-7 TM data were always applied to monitor land use dynamic change as the main data resource. Certainly, IRS, CBERS-2, and IKONOS data also were tested in small areas. In 2002, the SPOT-5 data, whose spatial resolution of the panchromatic image is 2.5 meters and the spectral one is 10 meters, were applied into update the land use base map at the 1:10000 scale in 26 Chinese cities. The purpose in this paper is to communicate the experience of SPOT-5 image processing with the colleagues.

  3. 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.

  4. Two-Slotted Surface Coil Array for Magnetic Resonance Imaging at 4 Tesla

    International Nuclear Information System (INIS)

    Solis, S. E.; Hernandez, J. A.; Rodriguez, A. O.; Tomasi, D.

    2008-01-01

    Arrays of antennas have been widely accepted for magnetic resonance imaging applications due to their high signal-to-noise ratio (SNR) over large volumes of interest. A new surface coil based on the magnetron tube and called slotted surface coil, has been recently introduced by our group. This coil design experimentally demonstrated a significant improvement over the circular-shaped coil when used in the receive-only mode. The slotted coils formed a two-sheet structure with a 90 deg. separation and each coil had 6 circular slots. Numerical simulations were performed using the finite element method for this coil design to study the behaviour of the array magnetic field. Then, we developed a two-coil array for brain magnetic resonance imaging to be operated at the resonant frequency of 170 MHz in the transceiver mode. Phantom images were acquired with our coil array and standard pulse sequences on a research-dedicated 4 Tesla scanner. Numerical simulations demonstrated that electromagnetic interaction between the coil elements is negligible, and that the magnetic field showed a good uniformity. In vitro images showed the feasibility of this coil array for standard pulses for high field magnetic resonance imaging

  5. Surface mineral maps of Afghanistan derived from HyMap imaging spectrometer data, version 2

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.

    2013-01-01

    This report presents a new version of surface mineral maps derived from HyMap imaging spectrometer data collected over Afghanistan in the fall of 2007. This report also describes the processing steps applied to the imaging spectrometer data. The 218 individual flight lines composing the Afghanistan dataset, covering more than 438,000 square kilometers, were georeferenced to a mosaic of orthorectified Landsat images. The HyMap data were converted from radiance to reflectance using a radiative transfer program in combination with ground-calibration sites and a network of cross-cutting calibration flight lines. The U.S. Geological Survey Material Identification and Characterization Algorithm (MICA) was used to generate two thematic maps of surface minerals: a map of iron-bearing minerals and other materials, which have their primary absorption features at the shorter wavelengths of the reflected solar wavelength range, and a map of carbonates, phyllosilicates, sulfates, altered minerals, and other materials, which have their primary absorption features at the longer wavelengths of the reflected solar wavelength range. In contrast to the original version, version 2 of these maps is provided at full resolution of 23-meter pixel size. The thematic maps, MICA summary images, and the material fit and depth images are distributed in digital files linked to this report, in a format readable by remote sensing software and Geographic Information Systems (GIS). The digital files can be downloaded from http://pubs.usgs.gov/ds/787/downloads/.

  6. Investigation of the Entrance Surface Dose and Dose to Different Organs in Lumbar Spine Imaging

    Directory of Open Access Journals (Sweden)

    Sina S

    2014-12-01

    Full Text Available Background: Dose assessment using proper dosimeters is especially important in radiation protection optimization and imaging justification in diagnostic radiology. Objective: The aim of this study is to obtain the Entrance Skin Dose (ESD of patients undergoing lumbar spine imaging using two thermoluminescence dosimeters TLD-100 (LiF: Mg, Ti and GR-200 (LiF: Mg, Cu, P and also to obtain the absorbed dose to different organs in lumbar spine imaging with several views. Methods: To measure the ESD values of the patients undergoing lumbar spine imaging, the two TLD types were put on their skin surface. The ESD values for different views of lumbar spine imaging were also measured by putting the TLDs at the surface of the Rando phantom. Several TLD chips were inserted inside different organs of Rando phantom to measure the absorbed dose to different organs in lumbar spine imaging. Results: The results indicate that there is a close agreement between the results of the two dosimeters. Based on the results of this experiment, the ESD dose of the 16 patients included in this study varied between 2.71 mGy and 26.29 mGy with the average of 11.89 mGy for TLD-100, and between 2.55 mGy and 27.41 mGy with the average of 12.32 mGy for GR-200 measurements. The ESDs obtained by putti