WorldWideScience

Sample records for spirit high-resolution imaging

  1. Section on High Resolution Optical Imaging (HROI)

    Data.gov (United States)

    Federal Laboratory Consortium — The Section on High Resolution Optical Imaging (HROI) develops novel technologies for studying biological processes at unprecedented speed and resolution. Research...

  2. Classification of high resolution satellite images

    OpenAIRE

    Karlsson, Anders

    2003-01-01

    In this thesis the Support Vector Machine (SVM)is applied on classification of high resolution satellite images. Sveral different measures for classification, including texture mesasures, 1st order statistics, and simple contextual information were evaluated. Additionnally, the image was segmented, using an enhanced watershed method, in order to improve the classification accuracy.

  3. Granulometric maps from high resolution satellite images:

    OpenAIRE

    Chopin, Franck; Mering, Catherine

    2002-01-01

    A new method of land cover mapping from satellite images using granulometric analysis is presented here. Discontinuous landscapes such as steppian bushes of semi arid regions and recently growing urban settlements are especially concerned by this study. Spatial organisations of the land cover are quantified by means of the size distribution analysis of the land cover units extracted from high resolution remotely sensed images. A granulometric map is built by automatic classification of every ...

  4. High-resolution reconstruction for terahertz imaging.

    Science.gov (United States)

    Xu, Li-Min; Fan, Wen-Hui; Liu, Jia

    2014-11-20

    We present a high-resolution (HR) reconstruction model and algorithms for terahertz imaging, taking advantage of super-resolution methodology and algorithms. The algorithms used include projection onto a convex sets approach, iterative backprojection approach, Lucy-Richardson iteration, and 2D wavelet decomposition reconstruction. Using the first two HR reconstruction methods, we successfully obtain HR terahertz images with improved definition and lower noise from four low-resolution (LR) 22×24 terahertz images taken from our homemade THz-TDS system at the same experimental conditions with 1.0 mm pixel. Using the last two HR reconstruction methods, we transform one relatively LR terahertz image to a HR terahertz image with decreased noise. This indicates potential application of HR reconstruction methods in terahertz imaging with pulsed and continuous wave terahertz sources.

  5. Limiting liability via high resolution image processing

    Energy Technology Data Exchange (ETDEWEB)

    Greenwade, L.E.; Overlin, T.K.

    1996-12-31

    The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as `evidence ready`, even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence.

  6. GRANULOMETRIC MAPS FROM HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    Catherine Mering

    2011-05-01

    Full Text Available A new method of land cover mapping from satellite images using granulometric analysis is presented here. Discontinuous landscapes such as steppian bushes of semi arid regions and recently growing urban settlements are especially concerned by this study. Spatial organisations of the land cover are quantified by means of the size distribution analysis of the land cover units extracted from high resolution remotely sensed images. A granulometric map is built by automatic classification of every pixel of the image according to the granulometric density inside a sliding neighbourhood. Granulometric mapping brings some advantages over traditional thematic mapping by remote sensing by focusing on fine spatial events and small changes in one peculiar category of the landscape.

  7. 3D High Resolution l1-SPIRiT Reconstruction on Gadgetron based Cloud

    DEFF Research Database (Denmark)

    Xue, Hui; Kelmann, Peter; Inati, Souheil

    framework to support distributed computing in a cloud environment. This extension is named GT-Plus. A cloud version of 3D l1-SPIRiT was implemented on the GT-Plus framework. We demonstrate that a 3mins reconstruction could be achieved for 1mm3 isotropic resolution neuro scans with significantly improved......Applying non-linear reconstruction to high resolution 3D MRI is challenging because of the lengthy computing time needed for those iterative algorithms. To achieve practical processing duration to enable clinical usage of non-linear reconstruction, we have extended previously published Gadgetron...

  8. Dynamic high resolution imaging of rats

    International Nuclear Information System (INIS)

    Miyaoka, R.S.; Lewellen, T.K.; Bice, A.N.

    1990-01-01

    A positron emission tomography with the sensitivity and resolution to do dynamic imaging of rats would be an invaluable tool for biological researchers. In this paper, the authors determine the biological criteria for dynamic positron emission imaging of rats. To be useful, 3 mm isotropic resolution and 2-3 second time binning were necessary characteristics for such a dedicated tomograph. A single plane in which two objects of interest could be imaged simultaneously was considered acceptable. Multi-layered detector designs were evaluated as a possible solution to the dynamic imaging and high resolution imaging requirements. The University of Washington photon history generator was used to generate data to investigate a tomograph's sensitivity to true, scattered and random coincidences for varying detector ring diameters. Intrinsic spatial uniformity advantages of multi-layered detector designs over conventional detector designs were investigated using a Monte Carlo program. As a result, a modular three layered detector prototype is being developed. A module will consist of a layer of five 3.5 mm wide crystals and two layers of six 2.5 mm wide crystals. The authors believe adequate sampling can be achieved with a stationary detector system using these modules. Economical crystal decoding strategies have been investigated and simulations have been run to investigate optimum light channeling methods for block decoding strategies. An analog block decoding method has been proposed and will be experimentally evaluated to determine whether it can provide the desired performance

  9. High resolution imaging of boron carbide microstructures

    International Nuclear Information System (INIS)

    MacKinnon, I.D.R.; Aselage, T.; Van Deusen, S.B.

    1986-01-01

    Two samples of boron carbide have been examined using high resolution transmission electron microscopy (HRTEM). A hot-pressed B 13 C 2 sample shows a high density of variable width twins normal to (10*1). Subtle shifts or offsets of lattice fringes along the twin plane and normal to approx.(10*5) were also observed. A B 4 C powder showed little evidence of stacking disorder in crystalline regions

  10. An improved IHS fusion for high resolution remote sensing images

    Science.gov (United States)

    Hu, Youjian; Zhang, Xiaohua

    2010-02-01

    Image fusion plays an important role in improving high resolution remote sensing images, as many Earth observation satellites provide both high-resolution panchromatic and multispectral images. To date, many image fusion techniques have been developed. Existing traditional image fusion techniques such as the intensity-hue-saturation (IHS) transform, wavelet transform and principal components analysis(PCA) methods may not be optimal for fusing the new generation commercial high-resolution satellite images such as IKONOS and Quick Bird. However, the available algorithms can hardly meet a satisfactory fusion requirement for high resolution remote sensing images. Among the existing fusion algorithms, the IHS technique is the most widely used one technique. But the color distortion of this technique is often obvious, especially when high resolution multispectral images are fused with its panchromatic images. This study presents a new fusion approach that integrates both IHS and histogram match techniques to reduce the color distortion of high resolution remote sensing fusion results. Different high resolution remote sensing images have been fused with this new approach. The result proves that the concept of the proposed improved IHS is promising, and it does significantly improve the fusion quality compared to conventional IHS transform fusion techniques.

  11. Very high resolution satellite data: New challenges in image analysis

    Digital Repository Service at National Institute of Oceanography (India)

    Sathe, P.V.; Muraleedharan, P.M.

    or other natural landscapes. Having very high resolution digital data over a landscape will however create new challenges in the field of atmospheric correction, ground registration, image processing and finally the image interpretation itself. Even...

  12. O-space with high resolution readouts outperforms radial imaging.

    Science.gov (United States)

    Wang, Haifeng; Tam, Leo; Kopanoglu, Emre; Peters, Dana C; Constable, R Todd; Galiana, Gigi

    2017-04-01

    While O-Space imaging is well known to accelerate image acquisition beyond traditional Cartesian sampling, its advantages compared to undersampled radial imaging, the linear trajectory most akin to O-Space imaging, have not been detailed. In addition, previous studies have focused on ultrafast imaging with very high acceleration factors and relatively low resolution. The purpose of this work is to directly compare O-Space and radial imaging in their potential to deliver highly undersampled images of high resolution and minimal artifacts, as needed for diagnostic applications. We report that the greatest advantages to O-Space imaging are observed with extended data acquisition readouts. A sampling strategy that uses high resolution readouts is presented and applied to compare the potential of radial and O-Space sequences to generate high resolution images at high undersampling factors. Simulations and phantom studies were performed to investigate whether use of extended readout windows in O-Space imaging would increase k-space sampling and improve image quality, compared to radial imaging. Experimental O-Space images acquired with high resolution readouts show fewer artifacts and greater sharpness than radial imaging with equivalent scan parameters. Radial images taken with longer readouts show stronger undersampling artifacts, which can cause small or subtle image features to disappear. These features are preserved in a comparable O-Space image. High resolution O-Space imaging yields highly undersampled images of high resolution and minimal artifacts. The additional nonlinear gradient field improves image quality beyond conventional radial imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Image processor for high resolution video

    International Nuclear Information System (INIS)

    Pessoa, P.P.; Assis, J.T.; Cardoso, S.B.; Lopes, R.T.

    1989-01-01

    In this paper, we discuss an image presentation and processing system developed in Turbo Pascal 5.0 Language. Our system allows the visualization and processing of images in 16 different colors, taken at a time from a set of 64 possible ones. Digital filters of the mean, mediam Laplacian, gradient and histograms equalization type have been implemented, so as to allow a better image quality. Possible applications of our system are also discussed e.g., satellites, computerized tomography, medicine, microscopes. (author) [pt

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

    Data.gov (United States)

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

  15. ON THE DESIGN OF HIGH RESOLUTION IMAGING SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. Eckardt

    2017-05-01

    Full Text Available The design of high-resolution systems is always a consideration of many parameters. Technological parameter of the imaging system, e.g. diameter of the imaging system, mass and power, as well as storage and data transfer, have an direct impact on spacecraft size and design. The paper describes the essential design parameters for the description of high-resolution systems.

  16. Reproducible high-resolution multispectral image acquisition in dermatology

    Science.gov (United States)

    Duliu, Alexandru; Gardiazabal, José; Lasser, Tobias; Navab, Nassir

    2015-07-01

    Multispectral image acquisitions are increasingly popular in dermatology, due to their improved spectral resolution which enables better tissue discrimination. Most applications however focus on restricted regions of interest, imaging only small lesions. In this work we present and discuss an imaging framework for high-resolution multispectral imaging on large regions of interest.

  17. High resolution imaging detectors and applications

    CERN Document Server

    Saha, Swapan K

    2015-01-01

    Interferometric observations need snapshots of very high time resolution of the order of (i) frame integration of about 100 Hz or (ii) photon-recording rates of several megahertz (MHz). Detectors play a key role in astronomical observations, and since the explanation of the photoelectric effect by Albert Einstein, the technology has evolved rather fast. The present-day technology has made it possible to develop large-format complementary metal oxide–semiconductor (CMOS) and charge-coupled device (CCD) array mosaics, orthogonal transfer CCDs, electron-multiplication CCDs, electron-avalanche photodiode arrays, and quantum-well infrared (IR) photon detectors. The requirements to develop artifact-free photon shot noise-limited images are higher sensitivity and quantum efficiency, reduced noise that includes dark current, read-out and amplifier noise, smaller point-spread functions, and higher spectral bandwidth. This book aims to address such systems, technologies and design, evaluation and calibration, control...

  18. Automatic Matching of High Resolution Satellite Images Based on RFM

    OpenAIRE

    JI Shunping; YUAN Xiuxiao

    2016-01-01

    A matching method for high resolution satellite images based on RFM is presented.Firstly,the RFM parameters are used to predict the initial parallax of corresponding points and the prediction accuracy is analyzed.Secondly,the approximate epipolar equation is constructed based on projection tracking and its accuracy is analyzed.Thirdly,approximate 1D image matching is executed on pyramid images and least square matching on base images.At last RANSAC is imbedded to eliminate mis-matching points...

  19. High-resolution SPECT for small-animal imaging

    International Nuclear Information System (INIS)

    Qi Yujin

    2006-01-01

    This article presents a brief overview of the development of high-resolution SPECT for small-animal imaging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pinhole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection efficiency. (authors)

  20. Automatic Matching of High Resolution Satellite Images Based on RFM

    Directory of Open Access Journals (Sweden)

    JI Shunping

    2016-02-01

    Full Text Available A matching method for high resolution satellite images based on RFM is presented.Firstly,the RFM parameters are used to predict the initial parallax of corresponding points and the prediction accuracy is analyzed.Secondly,the approximate epipolar equation is constructed based on projection tracking and its accuracy is analyzed.Thirdly,approximate 1D image matching is executed on pyramid images and least square matching on base images.At last RANSAC is imbedded to eliminate mis-matching points and matching results are obtained.Test results verified the method more robust and with higher matching rate,compared to 2D gray correlation method and the popular SIFT matching method,and the method preferably solved the question of high resolution satellite image matching with different stereo model,different time and large rotation images.

  1. High Resolution Imaging Ground Penetrating Radar Design and Simulation

    OpenAIRE

    Saunders II, Charles Phillip

    2014-01-01

    This paper describes the design and simulation of a microwave band, high resolution imaging ground penetrating radar. A conceptual explanation is given on the mechanics of wave-based imaging, followed by the governing radar equations. The performance specifications for the imaging system are given as inputs to the radar equations, which output the full system specifications. Those specifications are entered into a MATLAB simulation, and the simulation results are discussed with respect to bot...

  2. Structure Identification in High-Resolution Transmission Electron Microscopic Images

    DEFF Research Database (Denmark)

    Vestergaard, Jacob Schack; Kling, Jens; Dahl, Anders Bjorholm

    2014-01-01

    A connection between microscopic structure and macroscopic properties is expected for almost all material systems. High-resolution transmission electron microscopy is a technique offering insight into the atomic structure, but the analysis of large image series can be time consuming. The present ...

  3. High-resolution investigations of edge effects in neutron imaging

    International Nuclear Information System (INIS)

    Strobl, M.; Kardjilov, N.; Hilger, A.; Kuehne, G.; Frei, G.; Manke, I.

    2009-01-01

    Edge enhancement is the main effect measured by the so-called inline or propagation-based neutron phase contrast imaging method. The effect has originally been explained by diffraction, and high spatial coherence has been claimed to be a necessary precondition. However, edge enhancement has also been found in conventional imaging with high resolution. In such cases the effects can produce artefacts and hinder quantification. In this letter the edge effects at cylindrical shaped samples and long straight edges have been studied in detail. The enhancement can be explained by refraction and total reflection. Using high-resolution imaging, where spatial resolutions better than 50 μm could be achieved, refraction and total reflection peaks - similar to diffraction patterns - could be separated and distinguished.

  4. Adaptive optics with pupil tracking for high resolution retinal imaging.

    Science.gov (United States)

    Sahin, Betul; Lamory, Barbara; Levecq, Xavier; Harms, Fabrice; Dainty, Chris

    2012-02-01

    Adaptive optics, when integrated into retinal imaging systems, compensates for rapidly changing ocular aberrations in real time and results in improved high resolution images that reveal the photoreceptor mosaic. Imaging the retina at high resolution has numerous potential medical applications, and yet for the development of commercial products that can be used in the clinic, the complexity and high cost of the present research systems have to be addressed. We present a new method to control the deformable mirror in real time based on pupil tracking measurements which uses the default camera for the alignment of the eye in the retinal imaging system and requires no extra cost or hardware. We also present the first experiments done with a compact adaptive optics flood illumination fundus camera where it was possible to compensate for the higher order aberrations of a moving model eye and in vivo in real time based on pupil tracking measurements, without the real time contribution of a wavefront sensor. As an outcome of this research, we showed that pupil tracking can be effectively used as a low cost and practical adaptive optics tool for high resolution retinal imaging because eye movements constitute an important part of the ocular wavefront dynamics.

  5. Compact and mobile high resolution PET brain imager

    Science.gov (United States)

    Majewski, Stanislaw [Yorktown, VA; Proffitt, James [Newport News, VA

    2011-02-08

    A brain imager includes a compact ring-like static PET imager mounted in a helmet-like structure. When attached to a patient's head, the helmet-like brain imager maintains the relative head-to-imager geometry fixed through the whole imaging procedure. The brain imaging helmet contains radiation sensors and minimal front-end electronics. A flexible mechanical suspension/harness system supports the weight of the helmet thereby allowing for patient to have limited movements of the head during imaging scans. The compact ring-like PET imager enables very high resolution imaging of neurological brain functions, cancer, and effects of trauma using a rather simple mobile scanner with limited space needs for use and storage.

  6. Image thresholding in the high resolution target movement monitor

    Science.gov (United States)

    Moss, Randy H.; Watkins, Steve E.; Jones, Tristan H.; Apel, Derek B.; Bairineni, Deepti

    2009-03-01

    Image thresholding in the High Resolution Target Movement Monitor (HRTMM) is examined. The HRTMM was developed at the Missouri University of Science and Technology to detect and measure wall movements in underground mines to help reduce fatality and injury rates. The system detects the movement of a target with sub-millimeter accuracy based on the images of one or more laser dots projected on the target and viewed by a high-resolution camera. The relative position of the centroid of the laser dot (determined by software using thresholding concepts) in the images is the key factor in detecting the target movement. Prior versions of the HRTMM set the image threshold based on a manual, visual examination of the images. This work systematically examines the effect of varying threshold on the calculated centroid position and describes an algorithm for determining a threshold setting. First, the thresholding effects on the centroid position are determined for a stationary target. Plots of the centroid positions as a function of varying thresholds are obtained to identify clusters of thresholds for which the centroid position does not change for stationary targets. Second, the target is moved away from the camera in sub-millimeter increments and several images are obtained at each position and analyzed as a function of centroid position, target movement and varying threshold values. With this approach, the HRTMM can accommodate images in batch mode without the need for manual intervention. The capability for the HRTMM to provide automated, continuous monitoring of wall movement is enhanced.

  7. High resolution multiplexed functional imaging in live embryos (Conference Presentation)

    Science.gov (United States)

    Xu, Dongli; Zhou, Weibin; Peng, Leilei

    2017-02-01

    Fourier multiplexed fluorescence lifetime imaging (FmFLIM) scanning laser optical tomography (FmFLIM-SLOT) combines FmFLIM and Scanning laser optical tomography (SLOT) to perform multiplexed 3D FLIM imaging of live embryos. The system had demonstrate multiplexed functional imaging of zebrafish embryos genetically express Foster Resonant Energy Transfer (FRET) sensors. However, previous system has a 20 micron resolution because the focused Gaussian beam diverges quickly from the focused plane, makes it difficult to achieve high resolution imaging over a long projection depth. Here, we present a high-resolution FmFLIM-SLOT system with achromatic Bessel beam, which achieves 3 micron resolution in 3D deep tissue imaging. In Bessel-FmFLIM-SLOT, multiple laser excitation lines are firstly intensity modulated by a Michelson interferometer with a spinning polygon mirror optical delay line, which enables Fourier multiplexed multi-channel lifetime measurements. Then, a spatial light modulator and a prism are used to transform the modulated Gaussian laser beam to an achromatic Bessel beam. The achromatic Bessel beam scans across the whole specimen with equal angular intervals as sample rotated. After tomography reconstruction and the frequency domain lifetime analysis method, both the 3D intensity and lifetime image of multiple excitation-emission can be obtained. Using Bessel-FmFLIM-SLOT system, we performed cellular-resolution FLIM tomography imaging of live zebrafish embryo. Genetically expressed FRET sensors in these embryo will allow non-invasive observation of multiple biochemical processes in vivo.

  8. Multiscale wavelet filter for high resolution radioisotopic images

    Science.gov (United States)

    Pousse, A.; Dornier, C.; Fagot, L.; Parmentier, M.; Kastler, B.

    2000-12-01

    Radioisotopic Investigations are very useful for functional diagnosis, but available gamma cameras have poor spatial resolution. Development of new PSPMT based high-resolution detectors brings new interests to this medical imaging technique. However, the Poissonian nature of emitted photon flux and low count images due to low doses administered to the patients and to collimation, lead to images with granular aspect. This noisy appearance is particularly inconvenient when looking for cold nodules as in thyroid examinations. Low-pass filters, which reduce noise, are not well suited for detecting small cold nodules. An adapted translation invariant wavelet filter is designed which takes into account the poissonian feature of noise and preserves small sized structures. The filter was tested by Monte Carlo simulations, phantom and clinical thyroid scintigraphies. Cold spherical nodules as small as 4 mm in diameter are easily detected on filtered images acquired with IRIS (ARIES) high-resolution gamma ray imaging probe. Presentation of filtered images at different scales offering enhanced visual quality and lowered noise, simultaneously with original image, allows more comfortable analysis and improves scintigraphic diagnosis ability.

  9. Fast iterative segmentation of high resolution medical images

    International Nuclear Information System (INIS)

    Hebert, T.J.

    1996-01-01

    Various applications in positron emission tomography (PET), single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) require segmentation of 20 to 60 high resolution images of size 256x256 pixels in 3-9 seconds per image. This places particular constraints on the design of image segmentation algorithms. This paper examines the trade-offs in segmenting images based on fitting a density function to the pixel intensities using curve-fitting versus the maximum likelihood method. A quantized data representation is proposed and the EM algorithm for fitting a finite mixture density function to the quantized representation for an image is derived. A Monte Carlo evaluation of mean estimation error and classification error showed that the resulting quantized EM algorithm dramatically reduces the required computation time without loss of accuracy

  10. Quantum-Implementable Selective Reconstruction of High-Resolution Images

    Science.gov (United States)

    Perus, Mitja; Bischof, Horst; Caulfield, H. John; Kiong Loo, Chu

    2004-11-01

    This paper, written for interdisciplinary audience, presents computational image reconstruction implementable by quantum optics. The input-triggered selection of a high-resolution image among many stored ones, and its reconstruction if the input is occluded or noisy, has been successfully simulated. The original algorithm, based on the Hopfield associative neural net, was transformed in order to enable its quantum-wave implementation based on holography. The main limitations of the classical Hopfield net are much reduced with the simulated new quantum-optical implementation.

  11. DMD based digital speckle illumination for high resolution imaging

    Science.gov (United States)

    Shinde, Anant; Mishra, Ayush; Perinchery, Sandeep M.; Murukeshan, V. M.

    2017-06-01

    Spatially non-uniform illumination patterns have shown significant potential to improve the imaging. Recent developments in the patterned illumination microscopy have demonstrated that the use of an optical speckle as an illumination pattern significantly improves the imaging resolution at the same time reducing the computational overheads. We present a DMD based method for generation of digital speckle pattern. The generated digital speckle and uniform white light illumination are used as two illuminations to acquire images. The image reconstruction algorithm for blind structured illumination microscopy is used to get the high resolution image. Our approach does not require any calibration step or stringent control of the illumination, and dramatically simplifies the experimental set-up.

  12. High resolution ultrasound and photoacoustic imaging of single cells

    Directory of Open Access Journals (Sweden)

    Eric M. Strohm

    2016-03-01

    Full Text Available High resolution ultrasound and photoacoustic images of stained neutrophils, lymphocytes and monocytes from a blood smear were acquired using a combined acoustic/photoacoustic microscope. Photoacoustic images were created using a pulsed 532 nm laser that was coupled to a single mode fiber to produce output wavelengths from 532 nm to 620 nm via stimulated Raman scattering. The excitation wavelength was selected using optical filters and focused onto the sample using a 20× objective. A 1000 MHz transducer was co-aligned with the laser spot and used for ultrasound and photoacoustic images, enabling micrometer resolution with both modalities. The different cell types could be easily identified due to variations in contrast within the acoustic and photoacoustic images. This technique provides a new way of probing leukocyte structure with potential applications towards detecting cellular abnormalities and diseased cells at the single cell level.

  13. DETECTION OF BARCHAN DUNES IN HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    M. A. Azzaoui

    2016-06-01

    Full Text Available Barchan dunes are the fastest moving sand dunes in the desert. We developed a process to detect barchans dunes on High resolution satellite images. It consisted of three steps, we first enhanced the image using histogram equalization and noise reduction filters. Then, the second step proceeds to eliminate the parts of the image having a texture different from that of the barchans dunes. Using supervised learning, we tested a coarse to fine textural analysis based on Kolomogorov Smirnov test and Youden’s J-statistic on co-occurrence matrix. As an output we obtained a mask that we used in the next step to reduce the search area. In the third step we used a gliding window on the mask and check SURF features with SVM to get barchans dunes candidates. Detected barchans dunes were considered as the fusion of overlapping candidates. The results of this approach were very satisfying in processing time and precision.

  14. High Resolution Energetic X-ray Imager (HREXI)

    Science.gov (United States)

    Grindlay, Jonathan

    We propose to design and build the first imaging hard X-ray detector system that incorporates 3D stacking of closely packed detector readouts in finely-spaced imaging arrays with their required data processing and control electronics. In virtually all imaging astronomical detectors, detector readout is done with flex connectors or connections that are not vertical but rather horizontal , requiring loss of focal plane area. For high resolution pixel detectors needed for high speed event-based X-ray imaging, from low energy applications (CMOS) with focusing X-ray telescopes, to hard X-ray applications with pixelated CZT for large area coded aperture telescopes, this new detector development offers great promise. We propose to extend our previous and current APRA supported ProtoEXIST program that has developed the first large area imaging CZT detectors and demonstrated their astrophysical capabilities on two successful balloon flight to a next generation High Resolution Energetic X-ray Imager (HREXI), which would incorporate microvia technology for the first time to connect the readout ASIC on each CZT crystal directly to its control and data processing system. This 3-dimensional stacking of detector and readout/control system means that large area (>2m2) imaging detector planes for a High Resolution Wide-field hard X-ray telescope can be built with initially greatly reduced detector gaps and ultimately with no gaps. This increases detector area, efficiency, and simplicity of detector integration. Thus higher sensitivity wide-field imagers will be possible at lower cost. HREXI will enable a post-Swift NASA mission such as the EREXS concept proposed to PCOS to be conducted as a future MIDEX mission. This mission would conduct a high resolution (<2 arcmin) , broad band (5 200 keV) hard X-ray survey of black holes on all scales with ~10X higher sensitivity than Swift. In the current era of Time Domain Astrophysics, such a survey capability, in conjunction with a n

  15. High-resolution imaging methods in array signal processing

    DEFF Research Database (Denmark)

    Xenaki, Angeliki

    The purpose of this study is to develop methods in array signal processing which achieve accurate signal reconstruction from limited observations resulting in high-resolution imaging. The focus is on underwater acoustic applications and sonar signal processing both in active (transmit and receive...... in active sonar signal processing for detection and imaging of submerged oil contamination in sea water from a deep-water oil leak. The submerged oil _eld is modeled as a uid medium exhibiting spatial perturbations in the acoustic parameters from their mean ambient values which cause weak scattering......) and passive (only receive) mode. The study addresses the limitations of existing methods and shows that, in many cases, the proposed methods overcome these limitations and outperform traditional methods for acoustic imaging. The project comprises two parts; The first part deals with computational methods...

  16. Segmentation Based Fuzzy Classification of High Resolution Images

    Science.gov (United States)

    Rao, Mukund; Rao, Suryaprakash; Masser, Ian; Kasturirangan, K.

    images, we build a much needed bridge between the methodology domains of GIS and Image Analysis. The idea of having an integrated 'geographical information processing' environment is becoming much more realistic now that 'GIS' objects can be used for analysing an image and vice versa, new 'GIS' objects can be directly generated without ignoring the rich information environment of geographical concepts, relations and scales. In the above scenario, the main aim of this project is to assess whether object-oriented classification techniques would be more suitable for remote sensing images - specifically in the context of high resolution images. The paper basically examines potentials of classification techniques - especially segmentation based methods that is based on an object-semantics and that uses not only the spectral information but also the spatial characteristics; studies the integration of segmentation and fuzzy-classification to derive user-oriented information from the high resolution images and evaluates how such segmentation based classification compares with the more common pixel- based statistical technique. Segmentation based fuzzy classification is applied to high resolution images from IRS and for 1m images from satellites - especially to extract urban information.

  17. A parallel solution for high resolution histological image analysis.

    Science.gov (United States)

    Bueno, G; González, R; Déniz, O; García-Rojo, M; González-García, J; Fernández-Carrobles, M M; Vállez, N; Salido, J

    2012-10-01

    This paper describes a general methodology for developing parallel image processing algorithms based on message passing for high resolution images (on the order of several Gigabytes). These algorithms have been applied to histological images and must be executed on massively parallel processing architectures. Advances in new technologies for complete slide digitalization in pathology have been combined with developments in biomedical informatics. However, the efficient use of these digital slide systems is still a challenge. The image processing that these slides are subject to is still limited both in terms of data processed and processing methods. The work presented here focuses on the need to design and develop parallel image processing tools capable of obtaining and analyzing the entire gamut of information included in digital slides. Tools have been developed to assist pathologists in image analysis and diagnosis, and they cover low and high-level image processing methods applied to histological images. Code portability, reusability and scalability have been tested by using the following parallel computing architectures: distributed memory with massive parallel processors and two networks, INFINIBAND and Myrinet, composed of 17 and 1024 nodes respectively. The parallel framework proposed is flexible, high performance solution and it shows that the efficient processing of digital microscopic images is possible and may offer important benefits to pathology laboratories. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  18. High-resolution imaging in the scanning transmission electron microscope

    International Nuclear Information System (INIS)

    Pennycook, S.J.; Jesson, D.E.

    1992-03-01

    The high-resolution imaging of crystalline materials in the scanning transmission electron microscopy (STEM) is reviewed with particular emphasis on the conditions under which an incoherent image can be obtained. It is shown that a high-angle annular detector can be used to break the coherence of the imaging process, in the transverse plane through the geometry of the detector, or in three dimensions if multiphonon diffuse scattering is detected. In the latter case, each atom can be treated as a highly independent source of high-angle scattering. The most effective fast electron states are therefore tightly bound s-type Bloch states. Furthermore, they add constructively for each incident angle in the coherent STEM probe, so that s states are responsible for practically the entire image contrast. Dynamical effects are largely removed, and almost perfect incoherent imaging is achieved. s states are relatively insensitive to neighboring strings, so that incoherent imaging is maintained for superlattice and interfaces, and supercell calculations are unnecessary. With an optimum probe profile, the incoherent image represents a direct image of the crystal projection, with compositional sensitivity built in through the strong dependence of the scattering cross sections on atomic number Z

  19. High-Resolution Mars Camera Test Image of Moon (Infrared)

    Science.gov (United States)

    2005-01-01

    This crescent view of Earth's Moon in infrared wavelengths comes from a camera test by NASA's Mars Reconnaissance Orbiter spacecraft on its way to Mars. The mission's High Resolution Imaging Science Experiment camera took the image on Sept. 8, 2005, while at a distance of about 10 million kilometers (6 million miles) from the Moon. The dark feature on the right is Mare Crisium. From that distance, the Moon would appear as a star-like point of light to the unaided eye. The test verified the camera's focusing capability and provided an opportunity for calibration. The spacecraft's Context Camera and Optical Navigation Camera also performed as expected during the test. The Mars Reconnaissance Orbiter, launched on Aug. 12, 2005, is on course to reach Mars on March 10, 2006. After gradually adjusting the shape of its orbit for half a year, it will begin its primary science phase in November 2006. From the mission's planned science orbit about 300 kilometers (186 miles) above the surface of Mars, the high resolution camera will be able to discern features as small as one meter or yard across.

  20. Hyperresolution: an hyperspectral and high resolution imager for Earth observation

    Science.gov (United States)

    De Vidi, R.; Chiarantini, L.; Bini, A.

    2017-11-01

    Hyperspectral space imagery is an emerging technology that supports many scientific, civil, security and defence operational applications. The main advantage of this remote sensing technique is that it allows the so-called Feature Extraction: in fact the spectral signature allows the recognition of the materials composing the scene. Hyperspectral Products and their applications have been investigated in the past years by Galileo Avionica to direct the instrument characteristics design. Sample products have been identified in the civil / environment monitoring fields (such as coastal monitoring, vegetation, hot spot and urban classification) and in defense / security applications: their performances have been verified by means of airborne flight campaigns. The Hyperspectral and High Resolution Imager is a space-borne instrument that implement a pushbroom technique to get strip spectral images over the Hyperspectral VNIR and SWIR bands, with a ground sample distance at nadir of 20m in a 20 km wide ground swath, with 200 spectral channels, realizing an average spectral resolution of 10nm. The High Resolution Panchromatic Channel insists in the same swath to allow for multiresolution data fusion of hyperspectral imagery.

  1. High resolution 3D imaging of synchrotron generated microbeams

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, Frank M., E-mail: frank.gagliardi@wbrc.org.au [Alfred Health Radiation Oncology, The Alfred, Melbourne, Victoria 3004, Australia and School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia); Cornelius, Iwan [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2500 (Australia); Blencowe, Anton [Division of Health Sciences, School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, South Australia 5000, Australia and Division of Information Technology, Engineering and the Environment, Mawson Institute, University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Franich, Rick D. [School of Applied Sciences and Health Innovations Research Institute, RMIT University, Melbourne, Victoria 3000 (Australia); Geso, Moshi [School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia)

    2015-12-15

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

  2. Two simple image slicers for high resolution spectroscopy

    Science.gov (United States)

    Tala, M.; Vanzi, L.; Avila, G.; Guirao, C.; Pecchioli, E.; Zapata, A.; Pieralli, F.

    2017-04-01

    We present the design, manufacturing, test and performance of two image slicers for high resolution spectroscopy. Based on the classical Bowen-Walraven concept, our slicers allow to make two slices of the image of the input fibre. We introduce the idea of a second fibre that can be cropped in half to reach the same width of the science target fibre and that can be used for simultaneous wavelength reference. The slicers presented are mirror and prism based, respectively. Both devices work within expectation, showing differences mainly in their efficiency. The prism based slicer is the solution that was adopted for the FIDEOS spectrograph, an instrument built by the AIUC for the ESO 1m telescope of La Silla. Test spectra obtained with this instrument are included as examples of a real application of the device.

  3. High resolution reversible color images on photonic crystal substrates.

    Science.gov (United States)

    Kang, Pilgyu; Ogunbo, Samuel O; Erickson, David

    2011-08-16

    When light is incident on a crystalline structure with appropriate periodicity, some colors will be preferentially reflected (Joannopoulos, J. D.; Meade, R. D.; Winn, J. N. Photonic crystals: molding the flow of light; Princeton University Press: Princeton, NJ, 1995; p ix, 137 pp). These photonic crystals and the structural color they generate represent an interesting method for creating reflective displays and drawing devices, since they can achieve a continuous color response and do not require back lighting (Joannopoulos, J. D.; Villeneuve, P. R.; Fan, S. H. Photonic crystals: Putting a new twist on light. Nature 1997, 386, 143-149; Graham-Rowe, D. Tunable structural colour. Nat. Photonics 2009, 3, 551-553.; Arsenault, A. C.; Puzzo, D. P.; Manners, I.; Ozin, G. A. Photonic-crystal full-colour displays. Nat. Photonics 2007, 1, 468-472; Walish, J. J.; Kang, Y.; Mickiewicz, R. A.; Thomas, E. L. Bioinspired Electrochemically Tunable Block Copolymer Full Color Pixels. Adv. Mater.2009, 21, 3078). Here we demonstrate a technique for creating erasable, high-resolution, color images using otherwise transparent inks on self-assembled photonic crystal substrates (Fudouzi, H.; Xia, Y. N. Colloidal crystals with tunable colors and their use as photonic papers. Langmuir 2003, 19, 9653-9660). Using inkjet printing, we show the ability to infuse fine droplets of silicone oils into the crystal, locally swelling it and changing the reflected color (Sirringhaus, H.; Kawase, T.; Friend, R. H.; Shimoda, T.; Inbasekaran, M.; Wu, W.; Woo, E. P. High-resolution inkjet printing of all-polymer transistor circuits. Science 2000, 290, 2123-2126). Multicolor images with resolutions as high as 200 μm are obtained from oils of different molecular weights with the lighter oils being able to penetrate deeper, yielding larger red shifts. Erasing of images is done simply by adding a low vapor pressure oil which dissolves the image, returning the substrate to its original state.

  4. High resolution microphotonic needle for endoscopic imaging (Conference Presentation)

    Science.gov (United States)

    Tadayon, Mohammad Amin; Mohanty, Aseema; Roberts, Samantha P.; Barbosa, Felippe; Lipson, Michal

    2017-02-01

    GRIN (Graded index) lens have revolutionized micro endoscopy enabling deep tissue imaging with high resolution. The challenges of traditional GRIN lenses are their large size (when compared with the field of view) and their limited resolution. This is because of the relatively weak NA in standard graded index lenses. Here we introduce a novel micro-needle platform for endoscopy with much higher resolution than traditional GRIN lenses and a FOV that corresponds to the whole cross section of the needle. The platform is based on polymeric (SU-8) waveguide integrated with a microlens micro fabricated on a silicon substrate using a unique molding process. Due to the high index of refraction of the material the NA of the needle is much higher than traditional GRIN lenses. We tested the probe in a fluorescent dye solution (19.6 µM Alexa Flour 647 solution) and measured a numerical aperture of 0.25, focal length of about 175 µm and minimal spot size of about 1.6 µm. We show that the platform can image a sample with the field of view corresponding to the cross sectional area of the waveguide (80x100 µm2). The waveguide size can in principle be modified to vary size of the imaging field of view. This demonstration, combined with our previous work demonstrating our ability to implant the high NA needle in a live animal, shows that the proposed system can be used for deep tissue imaging with very high resolution and high field of view.

  5. Semantic-based high resolution remote sensing image retrieval

    Science.gov (United States)

    Guo, Dihua

    High Resolution Remote Sensing (HRRS) imagery has been experiencing extraordinary development in the past decade. Technology development means increased resolution imagery is available at lower cost, making it a precious resource for planners, environmental scientists, as well as others who can learn from the ground truth. Image retrieval plays an important role in managing and accessing huge image database. Current image retrieval techniques, cannot satisfy users' requests on retrieving remote sensing images based on semantics. In this dissertation, we make two fundamental contributions to the area of content based image retrieval. First, we propose a novel unsupervised texture-based segmentation approach suitable for accurately segmenting HRRS images. The results of existing segmentation algorithms dramatically deteriorate if simply adopted to HRRS images. This is primarily clue to the multi-texture scales and the high level noise present in these images. Therefore, we propose an effective and efficient segmentation model, which is a two-step process. At high-level, we improved the unsupervised segmentation algorithm by coping with two special features possessed by HRRS images. By preprocessing images with wavelet transform, we not only obtain multi-resolution images but also denoise the original images. By optimizing the splitting results, we solve the problem of textons in HRRS images existing in different scales. At fine level, we employ fuzzy classification segmentation techniques with adjusted parameters for different land cover. We implement our algorithm using real world 1-foot resolution aerial images. Second, we devise methodologies to automatically annotate HRRS images based on semantics. In this, we address the issue of semantic feature selection, the major challenge faced by semantic-based image retrieval. To discover and make use of hidden semantics of images is application dependent. One type of the semantics in HRRS image is conveyed by composite

  6. Precision cosmology with time delay lenses: high resolution imaging requirements

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Xiao-Lei; Liao, Kai [Department of Astronomy, Beijing Normal University, 19 Xinjiekouwai Street, Beijing, 100875 (China); Treu, Tommaso; Agnello, Adriano [Department of Physics, University of California, Broida Hall, Santa Barbara, CA 93106 (United States); Auger, Matthew W. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Marshall, Philip J., E-mail: xlmeng919@gmail.com, E-mail: tt@astro.ucla.edu, E-mail: aagnello@physics.ucsb.edu, E-mail: mauger@ast.cam.ac.uk, E-mail: liaokai@mail.bnu.edu.cn, E-mail: dr.phil.marshall@gmail.com [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, CA 94305 (United States)

    2015-09-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ''Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρ{sub tot}∝ r{sup −γ'} for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. However, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation

  7. Precision cosmology with time delay lenses: High resolution imaging requirements

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Xiao -Lei [Beijing Normal Univ., Beijing (China); Univ. of California, Santa Barbara, CA (United States); Treu, Tommaso [Univ. of California, Santa Barbara, CA (United States); Univ. of California, Los Angeles, CA (United States); Agnello, Adriano [Univ. of California, Santa Barbara, CA (United States); Univ. of California, Los Angeles, CA (United States); Auger, Matthew W. [Univ. of Cambridge, Cambridge (United Kingdom); Liao, Kai [Beijing Normal Univ., Beijing (China); Univ. of California, Santa Barbara, CA (United States); Univ. of California, Los Angeles, CA (United States); Marshall, Philip J. [Stanford Univ., Stanford, CA (United States)

    2015-09-28

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ``Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρtot∝ r–γ' for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. Furthermore, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive

  8. Cheetah: A high frame rate, high resolution SWIR image camera

    Science.gov (United States)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  9. Structure recognition from high resolution images of ceramic composites

    Energy Technology Data Exchange (ETDEWEB)

    Ushizima, Daniela; Perciano, Talita; Krishnan, Harinarayan; Loring, Burlen; Bale, Hrishikesh; Parkinson, Dilworth; Sethian, James

    2015-01-05

    Fibers provide exceptional strength-to-weight ratio capabilities when woven into ceramic composites, transforming them into materials with exceptional resistance to high temperature, and high strength combined with improved fracture toughness. Microcracks are inevitable when the material is under strain, which can be imaged using synchrotron X-ray computed micro-tomography (mu-CT) for assessment of material mechanical toughness variation. An important part of this analysis is to recognize fibrillar features. This paper presents algorithms for detecting and quantifying composite cracks and fiber breaks from high-resolution image stacks. First, we propose recognition algorithms to identify the different structures of the composite, including matrix cracks and fibers breaks. Second, we introduce our package F3D for fast filtering of large 3D imagery, implemented in OpenCL to take advantage of graphic cards. Results show that our algorithms automatically identify micro-damage and that the GPU-based implementation introduced here takes minutes, being 17x faster than similar tools on a typical image file.

  10. High resolution imaging system for Udaipur Solar Observatory

    Science.gov (United States)

    Bayanna, A. Raja; Louis, Rohan Eugene; Kumar, Brajesh; Mathew, Shibu K.; Venkatakrishnan, P.

    2007-09-01

    A Multi-Application Solar Telescope (MAST) is proposed to be installed at the Udaipur Solar Observatory (USO) in India to monitor the Sun in optical and near infra-red wavelengths. The median value of the Fried's parameter at this site is 4 cm. USO is in the process of building an Adaptive optics (AO) system in order to have diffraction limited performance of the MAST under this moderate seeing condition. AO helps in achieving high-resolution imaging by compensating the atmospheric turbulence in real-time. We have performed simulations to evaluate the performance of AO for various seeing conditions. It was concluded that with the present availability of AO system components, a 55 cm aperture telescope would yield optimum performance with AO, in combination with post-processing techniques like speckle imaging and phase diversity. At present, we are developing a proto-type AO system at USO to demonstrate its performance with a 15 cm Coudé refracting telescope as a preparation for the main AO system to be deployed on the MAST. The prototype AO system is being realized in two phases. In the first phase, we have developed an image stabilization system to compensate the global tilt of the wave-front. The second phase consists of sensing and correcting the local tilts of the wave-front by integrating a micro-machined membrane deformable mirror with the image stabilization system and is currently in progress. Here, we present the details of our proto-type AO system. We also present preliminary results obtained from simulations using Phase Diversity as a post processing technique.

  11. High-Resolution Imaging of Asteroids/Satellites with AO

    Science.gov (United States)

    Merline, William

    2012-02-01

    We propose to make high-resolution observations of asteroids using AO, to measure size, shape, and pole position (spin vectors), and/or to search for satellites. We have demonstrated that AO imaging allows determination of the pole/dimensions in 1 or 2 nights on a single target, rather than the years of observations with lightcurve inversion techniques that only yield poles and axial ratios, not true dimensions. Our new technique (KOALA) combines AO imaging with lightcurve and occultation data for optimum size/shape determinations. We request that LGS be available for faint targets, but using NGS AO, we will measure several large and intermediate asteroids that are favorably placed in spring/summer of 2012 for size/shape/pole. Accurately determining the volume from the often-irregular shape allows us to derive densities to much greater precision in cases where the mass is known, e.g., from the presence of a satellite. We will search several d! ozen asteroids for the presence of satellites, particularly in under-studied populations, particularly NEOs (we have recently achieved the first-ever optical image of an NEO binary [Merline et al. 2008b, IAUC 8977]). Satellites provide a real-life lab for testing collisional models. We will search for satellites around special objects at the request of lightcurve observers, and we will make a search for debris in the vicinity of Pluto, in support of the New Horizons mission. Our shape/size work requires observations over most of a full rotation period (typically several hours).

  12. Textural Segmentation of High-Resolution Sidescan Sonar Images

    National Research Council Canada - National Science Library

    Kalcic, Maria; Bibee, Dale

    1995-01-01

    .... The high resolution of the 455 kHz sonar imagery also provides much information about the surficial bottom sediments, however their acoustic scattering properties are not well understood at high frequencies...

  13. Step-Stare Image Gathering for High-Resolution Targeting

    National Research Council Canada - National Science Library

    Lavigne, Valerie; Ricard, Benoit

    2005-01-01

    Built around two infrared cameras and a high-speed opto-mechanical pointing mechanism, the Infrared Eye attempts to mimic the human eye by superimposing a high-resolution narrow field of view (first camera...

  14. High-resolution mechanical imaging of the kidney.

    Science.gov (United States)

    Streitberger, Kaspar-Josche; Guo, Jing; Tzschätzsch, Heiko; Hirsch, Sebastian; Fischer, Thomas; Braun, Jürgen; Sack, Ingolf

    2014-02-07

    The objective of this study was to test the feasibility and reproducibility of in vivo high-resolution mechanical imaging of the asymptomatic human kidney. Hereby nine volunteers were examined at three different physiological states of urinary bladder filling (a normal state, urinary urgency, and immediately after urinary relief). Mechanical imaging was performed of the in vivo kidney using three-dimensional multifrequency magnetic resonance elastography combined with multifrequency dual elastovisco inversion. Other than in classical elastography, where the storage and loss shear moduli are evaluated, we analyzed the magnitude |G(⁎)| and the phase angle φ of the complex shear modulus reconstructed by simultaneous inversion of full wave field data corresponding to 7 harmonic drive frequencies from 30 to 60Hz and a resolution of 2.5mm cubic voxel size. Mechanical parameter maps were derived with a spatial resolution superior to that in previous work. The group-averaged values of |G(⁎)| were 2.67±0.52kPa in the renal medulla, 1.64±0.17kPa in the cortex, and 1.17±0.21kPa in the hilus. The phase angle φ (in radians) was 0.89±0.12 in the medulla, 0.83±0.09 in the cortex, and 0.72±0.06 in the hilus. All regional differences were significant (Pkidney. |G(⁎)| and φ provide novel information on the viscoelastic properties of the kidney, which is potentially useful for the detection of renal lesions or fibrosis. © 2013 Published by Elsevier Ltd.

  15. Roads Data Conflation Using Update High Resolution Satellite Images

    Science.gov (United States)

    Abdollahi, A.; Riyahi Bakhtiari, H. R.

    2017-11-01

    Urbanization, industrialization and modernization are rapidly growing in developing countries. New industrial cities, with all the problems brought on by rapid population growth, need infrastructure to support the growth. This has led to the expansion and development of the road network. A great deal of road network data has made by using traditional methods in the past years. Over time, a large amount of descriptive information has assigned to these map data, but their geometric accuracy and precision is not appropriate to today's need. In this regard, the improvement of the geometric accuracy of road network data by preserving the descriptive data attributed to them and updating of the existing geo databases is necessary. Due to the size and extent of the country, updating the road network maps using traditional methods is time consuming and costly. Conversely, using remote sensing technology and geographic information systems can reduce costs, save time and increase accuracy and speed. With increasing the availability of high resolution satellite imagery and geospatial datasets there is an urgent need to combine geographic information from overlapping sources to retain accurate data, minimize redundancy, and reconcile data conflicts. In this research, an innovative method for a vector-to-imagery conflation by integrating several image-based and vector-based algorithms presented. The SVM method for image classification and Level Set method used to extract the road the different types of road intersections extracted from imagery using morphological operators. For matching the extracted points and to find the corresponding points, matching function which uses the nearest neighborhood method was applied. Finally, after identifying the matching points rubber-sheeting method used to align two datasets. Two residual and RMSE criteria used to evaluate accuracy. The results demonstrated excellent performance. The average root-mean-square error decreased from 11.8 to 4.1 m.

  16. Special issue on high-resolution optical imaging

    Science.gov (United States)

    Smith, Peter J. S.; Davis, Ilan; Galbraith, Catherine G.; Stemmer, Andreas

    2013-09-01

    The pace of development in the field of advanced microscopy is truly breath-taking, and is leading to major breakthroughs in our understanding of molecular machines and cell function. This special issue of Journal of Optics draws attention to a number of interesting approaches, ranging from fluorescence and imaging of unlabelled cells, to computational methods, all of which are describing the ever increasing detail of the dynamic behaviour of molecules in the living cell. This is a field which traditionally, and currently, demonstrates a marvellous interplay between the disciplines of physics, chemistry and biology, where apparent boundaries to resolution dissolve and living cells are viewed in ever more clarity. It is fertile ground for those interested in optics and non-conventional imaging to contribute high-impact outputs in the fields of cell biology and biomedicine. The series of articles presented here has been selected to demonstrate this interdisciplinarity and to encourage all those with a background in the physical sciences to 'dip their toes' into the exciting and dynamic discoveries surrounding cell function. Although single molecule super-resolution microscopy is commercially available, specimen preparation and interpretation of single molecule data remain a major challenge for scientists wanting to adopt the techniques. The paper by Allen and Davidson [1] provides a much needed detailed introduction to the practical aspects of stochastic optical reconstruction microscopy, including sample preparation, image acquisition and image analysis, as well as a brief description of the different variants of single molecule localization microscopy. Since super-resolution microscopy is no longer restricted to three-dimensional imaging of fixed samples, the review by Fiolka [2] is a timely introduction to techniques that have been successfully applied to four-dimensional live cell super-resolution microscopy. The combination of multiple high-resolution techniques

  17. High resolution Ceres HAMO atlas derived from Dawn FC images

    Science.gov (United States)

    Roatsch, Thomas; Kersten, Elke; Matz, Klaus-Dieter; Preusker, Frank; Scholten, Frank; Jaumann, Ralf; Raymond, Carol A.; Russell, Chris T.

    2016-04-01

    Introduction: NASA's Dawn spacecraft entered the orbit of dwarf planet Ceres in March 2015, and will characterize the geology, elemental and mineralogical composition, topography, shape, and internal structure of Ceres. One of the major goals of the mission is a global mapping of Ceres. Data: The Dawn mission was mapping Ceres in HAMO (High Altitude Mapping Orbit, 1475 km altitude) between August and October 2015. The framing camera took about 2,600 clear filter images with a resolution of about 140 m/pixel during these cycles. The images were taken with different viewing angles and different illumination conditions. We selected images from one cycle (cycle #1) for the mosaicking process to have similar viewing and illumination conditions. Very minor gaps in the coverage were filled with a few images from cycle #2. Data Processing: The first step of the processing chain towards the cartographic products is to ortho-rectify the images to the proper scale and map projec-tion type. This process requires detailed information of the Dawn orbit and attitude data and of the topography of the targets. Both, improved orientation and a high-resolution shape model, are provided by stereo processing (bundle block adjustment) of the HAMO stereo image dataset [3]. Ceres's HAMO shape model was used for the calculation of the ray intersection points while the map projection itself was done onto the reference sphere of Ceres with a radius of 470 km. The final step is the controlled mosaicking) of all images to a global mosaic of Ceres, the so-called basemap. Ceres map tiles: The Ceres atlas was produced in a scale of 1:750,000 and consists of 15 tiles that conform to the quadrangle scheme proposed by Greeley and Batson [4]. A map scale of 1:750,000 guarantees a mapping at the highest available Dawn resolution in HAMO. The individual tiles were extracted from the global mosaic and reprojected. Nomenclature: The Dawn team proposed 81 names for geological features. By international

  18. DSP accelerator for the wavelet compression/decompression of high- resolution images

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, M.A.; Gleason, S.S.; Jatko, W.B.

    1993-07-23

    A Texas Instruments (TI) TMS320C30-based S-Bus digital signal processing (DSP) module was used to accelerate a wavelet-based compression and decompression algorithm applied to high-resolution fingerprint images. The law enforcement community, together with the National Institute of Standards and Technology (NISI), is adopting a standard based on the wavelet transform for the compression, transmission, and decompression of scanned fingerprint images. A two-dimensional wavelet transform of the input image is computed. Then spatial/frequency regions are automatically analyzed for information content and quantized for subsequent Huffman encoding. Compression ratios range from 10:1 to 30:1 while maintaining the level of image quality necessary for identification. Several prototype systems were developed using SUN SPARCstation 2 with a 1280 {times} 1024 8-bit display, 64-Mbyte random access memory (RAM), Tiber distributed data interface (FDDI), and Spirit-30 S-Bus DSP-accelerators from Sonitech. The final implementation of the DSP-accelerated algorithm performed the compression or decompression operation in 3.5 s per print. Further increases in system throughput were obtained by adding several DSP accelerators operating in parallel.

  19. High-resolution seismic imaging of the Sohagpur Gondwana basin ...

    Indian Academy of Sciences (India)

    through a high-resolution seismic reflection study along six profiles, covering the central part of the. Sohagpur basin. The study reveals (1) ~1000 m thick, gently dipping Barakar Formation, (2) thick coal seams at a depth of 350–550 m, and (3) NNW–SSE to NW–SE striking steeply dipping normal faults defining rift geometry.

  20. High resolution SPM imaging of organic molecules with functionalized tips

    Czech Academy of Sciences Publication Activity Database

    Jelínek, Pavel

    2017-01-01

    Roč. 29, č. 34 (2017), 1-18, č. článku 343002. ISSN 0953-8984 R&D Projects: GA MŠk LM2015087; GA MŠk 8E15B010; GA ČR(CZ) GC14-16963J Grant - others:AV ČR(CZ) Praemium Academiae Institutional support: RVO:68378271 Keywords : atomic-force microscopy * scanning tunneling microscope * on-surface synthesis * single- molecule * AFM * STM * high resolution * molecule s * surfaces Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.649, year: 2016

  1. High Resolution Multispectral Flow Imaging of Cells with Extended Depth of Field, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposed is the development the extended depth of field (EDF) or confocal like imaging capabilities of a breakthrough multispectral high resolution imaging flow...

  2. High Resolution Multispectral Flow Imaging of Cells with Extended Depth of Field, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposed is the development the extended depth of field (EDF) or confocal like imaging capabilities of a breakthrough multispectral high resolution imaging flow...

  3. High resolution imaging of tunnels by magnetic resonance neurography

    Energy Technology Data Exchange (ETDEWEB)

    Subhawong, Ty K.; Thawait, Shrey K.; Machado, Antonio J.; Carrino, John A.; Chhabra, Avneesh [Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Wang, Kenneth C. [Baltimore VA Medical Center, Department of Radiology, Baltimore, MD (United States); Williams, Eric H. [Dellon Institute for Peripheral Nerve Surgery, Towson, MD (United States); Hashemi, Shahreyar Shar [Johns Hopkins Hospital, Division of Plastic and Reconstructive Surgery, Baltimore, MD (United States)

    2012-01-15

    Peripheral nerves often traverse confined fibro-osseous and fibro-muscular tunnels in the extremities, where they are particularly vulnerable to entrapment and compressive neuropathy. This gives rise to various tunnel syndromes, characterized by distinct patterns of muscular weakness and sensory deficits. This article focuses on several upper and lower extremity tunnels, in which direct visualization of the normal and abnormal nerve in question is possible with high resolution 3T MR neurography (MRN). MRN can also serve as a useful adjunct to clinical and electrophysiologic exams by discriminating adhesive lesions (perineural scar) from compressive lesions (such as tumor, ganglion, hypertrophic callous, or anomalous muscles) responsible for symptoms, thereby guiding appropriate treatment. (orig.)

  4. A new high-resolution electromagnetic method for subsurface imaging

    Science.gov (United States)

    Feng, Wanjie

    For most electromagnetic (EM) geophysical systems, the contamination of primary fields on secondary fields ultimately limits the capability of the controlled-source EM methods. Null coupling techniques were proposed to solve this problem. However, the small orientation errors in the null coupling systems greatly restrict the applications of these systems. Another problem encountered by most EM systems is the surface interference and geologic noise, which sometimes make the geophysical survey impossible to carry out. In order to solve these problems, the alternating target antenna coupling (ATAC) method was introduced, which greatly removed the influence of the primary field and reduced the surface interference. But this system has limitations on the maximum transmitter moment that can be used. The differential target antenna coupling (DTAC) method was proposed to allow much larger transmitter moments and at the same time maintain the advantages of the ATAC method. In this dissertation, first, the theoretical DTAC calculations were derived mathematically using Born and Wolf's complex magnetic vector. 1D layered and 2D blocked earth models were used to demonstrate that the DTAC method has no responses for 1D and 2D structures. Analytical studies of the plate model influenced by conductive and resistive backgrounds were presented to explain the physical phenomenology behind the DTAC method, which is the magnetic fields of the subsurface targets are required to be frequency dependent. Then, the advantages of the DTAC method, e.g., high-resolution, reducing the geologic noise and insensitive to surface interference, were analyzed using surface and subsurface numerical examples in the EMGIMA software. Next, the theoretical advantages, such as high resolution and insensitive to surface interference, were verified by designing and developing a low-power (moment of 50 Am 2) vertical-array DTAC system and testing it on controlled targets and scaled target coils. At last, a

  5. Towards Adaptive High-Resolution Images Retrieval Schemes

    Science.gov (United States)

    Kourgli, A.; Sebai, H.; Bouteldja, S.; Oukil, Y.

    2016-10-01

    Nowadays, content-based image-retrieval techniques constitute powerful tools for archiving and mining of large remote sensing image databases. High spatial resolution images are complex and differ widely in their content, even in the same category. All images are more or less textured and structured. During the last decade, different approaches for the retrieval of this type of images have been proposed. They differ mainly in the type of features extracted. As these features are supposed to efficiently represent the query image, they should be adapted to all kind of images contained in the database. However, if the image to recognize is somewhat or very structured, a shape feature will be somewhat or very effective. While if the image is composed of a single texture, a parameter reflecting the texture of the image will reveal more efficient. This yields to use adaptive schemes. For this purpose, we propose to investigate this idea to adapt the retrieval scheme to image nature. This is achieved by making some preliminary analysis so that indexing stage becomes supervised. First results obtained show that by this way, simple methods can give equal performances to those obtained using complex methods such as the ones based on the creation of bag of visual word using SIFT (Scale Invariant Feature Transform) descriptors and those based on multi scale features extraction using wavelets and steerable pyramids.

  6. Using Adobe Acrobat to create high-resolution line art images.

    Science.gov (United States)

    Woo, Hyoun Sik; Lee, Jeong Min

    2009-08-01

    The purpose of this article is to introduce a method for using Adobe Acrobat to make high-resolution and high-quality line art images. High-resolution and high-quality line art images for radiology journal submission can be generated using Adobe Acrobat as a steppingstone, and the customized PDF conversion settings can be used for converting hybrid images, including both bitmap and vector components.

  7. High-resolution gamma imaging; Imagerie gamma haute resolution

    Energy Technology Data Exchange (ETDEWEB)

    Parmentier, M.; Pousse, A.; Tamba, N.; Chavanelle, J.; Bakkali, A.; Kastler, B. [Centre Hospitalier Universitaire, Lab. Imagerie et Ingenierie pour la Sante, Faculte de Medecine, 25 - Besancon (France)

    2004-01-01

    Gamma imaging involves two-dimensional images of the volume distribution of a radioactive tracer previously injected into the organ under functional exploration. Our Besancon laboratory developed a gamma imager with a spatial resolution three or four times higher than a classic device, which is very useful for functional explorations on small animal, as recently demonstrated by work on myocyte apoptosis and necrosis scintigraphy in the rat. We expect progress in this promising medical imaging technology to be driven by developments in scintillating crystals and position-sensitive photomultiplier tubes, and by medical demand in applications such as early detection of breast cancer. (authors)

  8. Change detection in very high resolution multisensor optical images

    Science.gov (United States)

    Solano Correa, Yady T.; Bovolo, Francesca; Bruzzone, Lorenzo

    2014-10-01

    This work aims at developing an approach to the detection of changes in multisensor multitemporal VHR optical images. The main steps of the proposed method are: i) multisensor data homogenization; and ii) change detection in multisensor multitemporal VHR optical images. The proposed approach takes advantage of: the conversion to physical quantities suggested by Pacifici et. al.1 , the framework for the design of systems for change detection in VHR images presented by Bruzzone and Bovolo2 and the framework for unsupervised change detection presented by Bovolo and Bruzzone3. Multisensor data homogenization is achieved during pre-processing by taking into account differences in both radiometric and geometric dimensions. Whereas change detection was approached by extracting proper features from multisensor images such that they result to be comparable (at a given level of abstraction) even if extracted from images acquired by different sensors. In order to illustrate the results, a data set made up of a QuickBird and a WorldView-2 images - acquired in 2006 and 2010 respectively - over an area located in the Trentino region of Italy were used. However, the proposed approach is thought to be exportable to multitemporal images coming from passive sensors other than the two mentioned above. The experimental results obtained on the QuickBird and WorlView-2 image pair are accurate. Thus opening to further experiments on multitemporal images acquired by other sensors.

  9. Linearized inversion frameworks toward high-resolution seismic imaging

    KAUST Repository

    Aldawood, Ali

    2016-09-01

    Seismic exploration utilizes controlled sources, which emit seismic waves that propagate through the earth subsurface and get reflected off subsurface interfaces and scatterers. The reflected and scattered waves are recorded by recording stations installed along the earth surface or down boreholes. Seismic imaging is a powerful tool to map these reflected and scattered energy back to their subsurface scattering or reflection points. Seismic imaging is conventionally based on the single-scattering assumption, where only energy that bounces once off a subsurface scatterer and recorded by a receiver is projected back to its subsurface position. The internally multiply scattered seismic energy is considered as unwanted noise and is usually suppressed or removed from the recorded data. Conventional seismic imaging techniques yield subsurface images that suffer from low spatial resolution, migration artifacts, and acquisition fingerprint due to the limited acquisition aperture, number of sources and receivers, and bandwidth of the source wavelet. Hydrocarbon traps are becoming more challenging and considerable reserves are trapped in stratigraphic and pinch-out traps, which require highly resolved seismic images to delineate them. This thesis focuses on developing and implementing new advanced cost-effective seismic imaging techniques aiming at enhancing the resolution of the migrated images by exploiting the sparseness of the subsurface reflectivity distribution and utilizing the multiples that are usually neglected when imaging seismic data. I first formulate the seismic imaging problem as a Basis pursuit denoise problem, which I solve using an L1-minimization algorithm to obtain the sparsest migrated image corresponding to the recorded data. Imaging multiples may illuminate subsurface zones, which are not easily illuminated by conventional seismic imaging using primary reflections only. I then develop an L2-norm (i.e. least-squares) inversion technique to image

  10. Adaptive Optics Technology for High-Resolution Retinal Imaging

    Science.gov (United States)

    Lombardo, Marco; Serrao, Sebastiano; Devaney, Nicholas; Parravano, Mariacristina; Lombardo, Giuseppe

    2013-01-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging. PMID:23271600

  11. High-resolution seismic imaging of the Sohagpur Gondwana basin ...

    Indian Academy of Sciences (India)

    resolution seismic imaging of the Sohagpur Gondwana basin, central India: Evidence for syn-sedimentary subsidence and faulting. K Dhanam P Senthil Kumar D Mysaiah P Prabhakara Prasad T Seshunarayana. Volume 122 Issue 6 December ...

  12. A mechanical microcompressor for high resolution imaging of motile specimens

    OpenAIRE

    Zinskie, Jessica A.; Shribak, Michael; Bruist, Michael F.; Aufderheide, Karl J.; Janetopoulos, Chris

    2015-01-01

    In order to obtain fine details in 3 dimensions (3D) over time, it is critical for motile biological specimens to be appropriately immobilized. Of the many immobilization options available, the mechanical microcompressor offers many benefits. Our device, previously described, achieves gentle flattening of a cell, allowing us to image finely detailed structures of numerous organelles and physiological processes in living cells. We have imaged protozoa and other small metazoans using differenti...

  13. Dedicated mobile high resolution prostate PET imager with an insertable transrectal probe

    Science.gov (United States)

    Majewski, Stanislaw; Proffitt, James

    2010-12-28

    A dedicated mobile PET imaging system to image the prostate and surrounding organs. The imaging system includes an outside high resolution PET imager placed close to the patient's torso and an insertable and compact transrectal probe that is placed in close proximity to the prostate and operates in conjunction with the outside imager. The two detector systems are spatially co-registered to each other. The outside imager is mounted on an open rotating gantry to provide torso-wide 3D images of the prostate and surrounding tissue and organs. The insertable probe provides closer imaging, high sensitivity, and very high resolution predominately 2D view of the prostate and immediate surroundings. The probe is operated in conjunction with the outside imager and a fast data acquisition system to provide very high resolution reconstruction of the prostate and surrounding tissue and organs.

  14. Study of fish response using particle image velocimetry and high-speed, high-resolution imaging

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Z. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, M. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mueller, R. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gruensch, G. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2004-10-01

    Fish swimming has fascinated both engineers and fish biologists for decades. Digital particle image velocimetry (DPIV) and high-speed, high-resolution digital imaging are recently developed analysis tools that can help engineers and biologists better understand how fish respond to turbulent environments. This report details studies to evaluate DPIV. The studies included a review of existing literature on DPIV, preliminary studies to test the feasibility of using DPIV conducted at our Flow Biology Laboratory in Richland, Washington September through December 2003, and applications of high-speed, high-resolution digital imaging with advanced motion analysis to investigations of fish injury mechanisms in turbulent shear flows and bead trajectories in laboratory physical models. Several conclusions were drawn based on these studies, which are summarized as recommendations for proposed research at the end of this report.

  15. UARS High Resolution Doppler Imager (HRDI) Level 3AT V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Resolution Doppler Imager (HRDI) Level 3AT data product consists of daily, 65.536 second interval time-ordered vertical profiles of meridional and zonal...

  16. UARS High Resolution Doppler Imager (HRDI) Level 3AL V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Resolution Doppler Imager (HRDI) Level 3AL data product consists of daily, 4 degree increment latitude-ordered vertical profiles of meridional and zonal...

  17. High Resolution SZE Imaging of Galaxy Clusters with MUSTANG-2

    Science.gov (United States)

    Mason, Brian S.; Romero, Charles; Dicker, Simon; Mroczkowski, Tony; Stanchfield, Sara; Sayers, Jack; Czakon, Nicole G.; Sarazin, Craig L.; Golwala, Sunil R.; Devlin, Mark J.

    2016-01-01

    Over the past several years the 3.3mm MUSTANG bolometer camera on the GBT has been making pioneering, 10" resolution images of the Sunyaev-Zel'dovich Effect (SZE) in galaxy clusters. These measurements, focusing mainly on the CLASH sample, provide a view of the ICM state and dynamics which complements that provided by other common probes (x-ray imaging and spectroscopy and lower resolution SZE imaging). We present results from this survey, including ICM pressure profile measurements obtained by combining MUSTANG and BOLOCAM data, and discuss work that is underway. In early 2015, MUSTANG's next-generation successor (MUSTANG-2) achieved first light in an engineering run on the GBT. In early 2016 the fully populated 215-feedhorn MUSTANG-2 camera will be installed for an early science run. We present an overview of key SZ science that this instrument aims to address.

  18. Virtual ultrasound sources in high-resolution ultrasound imaging

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav; Jensen, Jørgen Arendt

    2002-01-01

    This paper investigates the concept of virtual source elements. It suggests a common framework for increasing the resolution, and penetration depth of several imaging modalities by applying synthetic aperture focusing (SAF). SAF is used either as a post focusing procedure on the beamformed data, ...

  19. Fast, High-Resolution Terahertz Radar Imaging at 25 Meters

    Science.gov (United States)

    Cooper, Ken B.; Dengler, Robert J.; Llombart, Nuria; Talukder, Ashit; Panangadan, Anand V.; Peay, Chris S.; Siegel, Peter H.

    2010-01-01

    We report improvements in the scanning speed and standoff range of an ultra-wide bandwidth terahertz (THz) imaging radar for person-borne concealed object detection. Fast beam scanning of the single-transceiver radar is accomplished by rapidly deflecting a flat, light-weight subreflector in a confocal Gregorian optical geometry. With RF back-end improvements also implemented, the radar imaging rate has increased by a factor of about 30 compared to that achieved previously in a 4 m standoff prototype instrument. In addition, a new 100 cm diameter ellipsoidal aluminum reflector yields beam spot diameters of approximately 1 cm over a 50x50 cm field of view at a range of 25 m, although some aberrations are observed that probably arise from misaligned optics. Through-clothes images of a concealed threat at 25 m range, acquired in 5 seconds, are presented, and the impact of reduced signal-to-noise from an even faster frame rate is analyzed. These results inform the system requirements for eventually achieving sub-second or video-rate THz radar imaging.

  20. High-resolution bispectral imager at 1000 frames per second.

    Science.gov (United States)

    Strojnik, Marija; Paez, Gonzalo

    2015-09-21

    We describe a bispectral, 1000-frames per second imaging instrument working simultaneously in two spectral bands. These bands may be selected for a specific application; however, we implement a pair centered at 4.3 μm and 4.66 μm. Synchronization is accomplished by employing a single focal plane array. To demonstrate the performance of the bispectral imager, we apply it to the methane flame of a Bunsen burner in a near conjugate configuration with flame image length subtending at about 200 pixels. The instrument detects bispectral puffing at 2 Hz, pulsations, and bispectral radiation oscillations, first reported here in two spectral intervals. The period of oscillatory spectral components in two bands is the same, about 3 Hz for this flame, with delay of a quarter period between them, first reported here. With 1-ms integration time, we detect significant formation of turbulence and vortices, especially pronounced in the region where the flame transitions into a plume. We display bispectral ratioed images of flames in near-real time with either the laboratory or the field device.

  1. High-resolution photoacoustic imaging of ocular tissues.

    Science.gov (United States)

    Silverman, Ronald H; Kong, Fanting; Chen, Y C; Lloyd, Harriet O; Kim, Hyung Ham; Cannata, Jonathan M; Shung, K Kirk; Coleman, D Jackson

    2010-05-01

    Optical coherence tomography (OCT) and ultrasound (US) are methods widely used for diagnostic imaging of the eye. These techniques detect discontinuities in optical refractive index and acoustic impedance, respectively. Because these both relate to variations in tissue density or composition, OCT and US images share a qualitatively similar appearance. In photoacoustic imaging (PAI), short light pulses are directed at tissues, pressure is generated due to a rapid energy deposition in the tissue volume and thermoelastic expansion results in generation of broadband US. PAI thus depicts optical absorption, which is independent of the tissue characteristics imaged by OCT or US. Our aim was to demonstrate the application of PAI in ocular tissues and to do so with lateral resolution comparable to OCT. We developed two PAI assemblies, both of which used single-element US transducers and lasers sharing a common focus. The first assembly had optical and 35-MHz US axes offset by a 30 degrees angle. The second assembly consisted of a 20-MHz ring transducer with a coaxial optics. The laser emitted 5-ns pulses at either 532 nm or 1064 nm, with spot sizes at the focus of 35 microm for the angled probe and 20 microm for the coaxial probe. We compared lateral resolution by scanning 12.5 microm diameter wire targets with pulse/echo US and PAI at each wavelength. We then imaged the anterior segment in whole ex vivo pig eyes and the choroid and ciliary body region in sectioned eyes. PAI data obtained at 1064 nm in the near infrared had higher penetration but reduced signal amplitude compared to that obtained using the 532 nm green wavelength. Images were obtained of the iris, choroid and ciliary processes. The zonules and anterior cornea and lens surfaces were seen at 532 nm. Because the laser spot size was significantly smaller than the US beamwidth at the focus, PAI images had superior resolution than those obtained using conventional US. Copyright 2010 World Federation for

  2. Positron emission mammography: high-resolution biochemical breast imaging.

    Science.gov (United States)

    Weinberg, Irving N; Beylin, David; Zavarzin, Valera; Yarnall, Steve; Stepanov, Pavel Y; Anashkin, Edward; Narayanan, Deepa; Dolinsky, Sergei; Lauckner, Kathrin; Adler, Lee P

    2005-02-01

    Positron emission mammography (PEM) provides images of biochemical activity in the breast with spatial resolution matching individual ducts (1.5 mm full-width at half-maximum). This spatial resolution, supported by count efficiency that results in high signal-to-noise ratio, allows confident visualization of intraductal as well as invasive breast cancers. Clinical trials with a full-breast PEM device have shown high clinical accuracy in characterizing lesions identified as suspicious on the basis of conventional imaging or physical examination (sensitivity 93%, specificity 83%, area under the ROC curve of 0.93), with high sensitivity preserved (91%) for intraductal cancers. Increased sensitivity did not come at a cost of reduced specificity. Considering that intraductal cancer represents more than 30% of reported cancers, and is the form of cancer with the highest probability of achieving surgical cure, it is likely that the use of PEM will complement anatomic imaging modalities in the areas of surgical planning, high-risk monitoring, and minimally invasive therapy. The quantitative nature of PET promises to assist researchers interested studying the response of putative cancer precursors (e.g., atypical ductal hyperplasia) to candidate prevention agents.

  3. A SPATIO-SPECTRAL CAMERA FOR HIGH RESOLUTION HYPERSPECTRAL IMAGING

    Directory of Open Access Journals (Sweden)

    S. Livens

    2017-08-01

    Full Text Available Imaging with a conventional frame camera from a moving remotely piloted aircraft system (RPAS is by design very inefficient. Less than 1 % of the flying time is used for collecting light. This unused potential can be utilized by an innovative imaging concept, the spatio-spectral camera. The core of the camera is a frame sensor with a large number of hyperspectral filters arranged on the sensor in stepwise lines. It combines the advantages of frame cameras with those of pushbroom cameras. By acquiring images in rapid succession, such a camera can collect detailed hyperspectral information, while retaining the high spatial resolution offered by the sensor. We have developed two versions of a spatio-spectral camera and used them in a variety of conditions. In this paper, we present a summary of three missions with the in-house developed COSI prototype camera (600–900 nm in the domains of precision agriculture (fungus infection monitoring in experimental wheat plots, horticulture (crop status monitoring to evaluate irrigation management in strawberry fields and geology (meteorite detection on a grassland field. Additionally, we describe the characteristics of the 2nd generation, commercially available ButterflEYE camera offering extended spectral range (475–925 nm, and we discuss future work.

  4. a Spatio-Spectral Camera for High Resolution Hyperspectral Imaging

    Science.gov (United States)

    Livens, S.; Pauly, K.; Baeck, P.; Blommaert, J.; Nuyts, D.; Zender, J.; Delauré, B.

    2017-08-01

    Imaging with a conventional frame camera from a moving remotely piloted aircraft system (RPAS) is by design very inefficient. Less than 1 % of the flying time is used for collecting light. This unused potential can be utilized by an innovative imaging concept, the spatio-spectral camera. The core of the camera is a frame sensor with a large number of hyperspectral filters arranged on the sensor in stepwise lines. It combines the advantages of frame cameras with those of pushbroom cameras. By acquiring images in rapid succession, such a camera can collect detailed hyperspectral information, while retaining the high spatial resolution offered by the sensor. We have developed two versions of a spatio-spectral camera and used them in a variety of conditions. In this paper, we present a summary of three missions with the in-house developed COSI prototype camera (600-900 nm) in the domains of precision agriculture (fungus infection monitoring in experimental wheat plots), horticulture (crop status monitoring to evaluate irrigation management in strawberry fields) and geology (meteorite detection on a grassland field). Additionally, we describe the characteristics of the 2nd generation, commercially available ButterflEYE camera offering extended spectral range (475-925 nm), and we discuss future work.

  5. High-resolution panoramic images with megapixel MWIR FPA

    Science.gov (United States)

    Leboucher, Vincent; Aubry, Gilles

    2014-06-01

    In the continuity of its current strategy, HGH maintains a deep effort in developing its most recent product family: the infrared (IR) panoramic 360-degree surveillance sensors. During the last two years, HGH optimized its prototype Middle Wave IR (MWIR) panoramic sensor IR Revolution 360 HD that gave birth to Spynel-S product. Various test campaigns proved its excellent image quality. Cyclope, the software associated with Spynel, benefitted from recent image processing improvements and new functionalities such as target geolocalization, long range sensor slue to cue and facilitated forensics analysis. In the frame of the PANORAMIR project sustained by the DGA (Délégation Générale de l'Armement), HGH designed a new extra large resolution sensor including a MWIR megapixel Focal Plane Array (FPA) detector (1280×1024 pixels). This new sensor is called Spynel-X. It provides outstanding resolution 360-degree images (with more than 100 Mpixels). The mechanical frame of Spynel (-S and -X) was designed with the collaboration of an industrial design agency. Spynel got the "Observeur du Design 2013" label.

  6. Towards high-resolution neutron imaging on IMAT

    Science.gov (United States)

    Minniti, T.; Tremsin, A. S.; Vitucci, G.; Kockelmann, W.

    2018-01-01

    IMAT is a new cold-neutron imaging facility at the neutron spallation source ISIS at the Rutherford Appleton Laboratory, U.K.. The ISIS pulsed source enables energy-selective and energy-resolved neutron imaging via time-of-flight (TOF) techniques, which are available in addition to the white-beam neutron radiography and tomography options. A spatial resolution of about 50 μm for white-beam neutron radiography was achieved early in the IMAT commissioning phase. In this work we have made the first steps towards achieving higher spatial resolution. A white-beam radiography with 18 μm spatial resolution was achieved in this experiment. This result was possible by using the event counting neutron pixel detector based on micro-channel plates (MCP) coupled with a Timepix readout chip with 55 μm sized pixels, and by employing an event centroiding technique. The prospects for energy-selective neutron radiography for this centroiding mode are discussed.

  7. Image Quality in High-resolution and High-cadence Solar Imaging

    Science.gov (United States)

    Denker, C.; Dineva, E.; Balthasar, H.; Verma, M.; Kuckein, C.; Diercke, A.; González Manrique, S. J.

    2018-03-01

    Broad-band imaging and even imaging with a moderate bandpass (about 1 nm) provides a photon-rich environment, where frame selection (lucky imaging) becomes a helpful tool in image restoration, allowing us to perform a cost-benefit analysis on how to design observing sequences for imaging with high spatial resolution in combination with real-time correction provided by an adaptive optics (AO) system. This study presents high-cadence (160 Hz) G-band and blue continuum image sequences obtained with the High-resolution Fast Imager (HiFI) at the 1.5-meter GREGOR solar telescope, where the speckle-masking technique is used to restore images with nearly diffraction-limited resolution. The HiFI employs two synchronized large-format and high-cadence sCMOS detectors. The median filter gradient similarity (MFGS) image-quality metric is applied, among others, to AO-corrected image sequences of a pore and a small sunspot observed on 2017 June 4 and 5. A small region of interest, which was selected for fast-imaging performance, covered these contrast-rich features and their neighborhood, which were part of Active Region NOAA 12661. Modifications of the MFGS algorithm uncover the field- and structure-dependency of this image-quality metric. However, MFGS still remains a good choice for determining image quality without a priori knowledge, which is an important characteristic when classifying the huge number of high-resolution images contained in data archives. In addition, this investigation demonstrates that a fast cadence and millisecond exposure times are still insufficient to reach the coherence time of daytime seeing. Nonetheless, the analysis shows that data acquisition rates exceeding 50 Hz are required to capture a substantial fraction of the best seeing moments, significantly boosting the performance of post-facto image restoration.

  8. AUTOMATIC INTERPRETATION OF HIGH RESOLUTION SAR IMAGES: FIRST RESULTS OF SAR IMAGE SIMULATION FOR SINGLE BUILDINGS

    Directory of Open Access Journals (Sweden)

    J. Tao

    2012-09-01

    Full Text Available Due to the all-weather data acquisition capabilities, high resolution space borne Synthetic Aperture Radar (SAR plays an important role in remote sensing applications like change detection. However, because of the complex geometric mapping of buildings in urban areas, SAR images are often hard to interpret. SAR simulation techniques ease the visual interpretation of SAR images, while fully automatic interpretation is still a challenge. This paper presents a method for supporting the interpretation of high resolution SAR images with simulated radar images using a LiDAR digital surface model (DSM. Line features are extracted from the simulated and real SAR images and used for matching. A single building model is generated from the DSM and used for building recognition in the SAR image. An application for the concept is presented for the city centre of Munich where the comparison of the simulation to the TerraSAR-X data shows a good similarity. Based on the result of simulation and matching, special features (e.g. like double bounce lines, shadow areas etc. can be automatically indicated in SAR image.

  9. High Resolution MALDI Imaging Mass Spectrometry of Retinal Tissue Lipids

    Science.gov (United States)

    Anderson, David M. G.; Ablonczy, Zsolt; Koutalos, Yiannis; Spraggins, Jeffrey; Crouch, Rosalie K.; Caprioli, Richard M.; Schey, Kevin L.

    2014-01-01

    Matrix assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) has the ability to provide an enormous amount of information on the abundances and spatial distributions of molecules within biological tissues. The rapid progress in the development of this technology significantly improves our ability to analyze smaller and smaller areas and features within tissues. The mammalian eye has evolved over millions of years to become an essential asset for survival, providing important sensory input of an organism’s surroundings. The highly complex sensory retina of the eye is comprised of numerous cell types organized into specific layers with varying dimensions, the thinnest of which is the 10 μm retinal pigment epithelium (RPE). This single cell layer and the photoreceptor layer contain the complex biochemical machinery required to convert photons of light into electrical signals that are transported to the brain by axons of retinal ganglion cells. Diseases of the retina including age related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy occur when the functions of these cells are interrupted by molecular processes that are not fully understood. In this report, we demonstrate the use of high spatial resolution MALDI IMS and FT-ICR tandem mass spectrometry in the Abca4−/− knockout mouse model of Stargardt disease, a juvenile onset form of macular degeneration. The spatial distributions and identity of lipid and retinoid metabolites are shown to be unique to specific retinal cell layers. PMID:24819461

  10. High-Resolution Seismic Imaging of Near-Surface Voids

    Science.gov (United States)

    Gritto, R.; Korneev, V. A.; Elobaid, E. A.; Mohamed, F.; Sadooni, F.

    2017-12-01

    A major hazard in Qatar is the presence of karst, which is ubiquitous throughout the country including depressions, sinkholes, and caves. Causes for the development of karst include faulting and fracturing where fluids find pathways through limestone and dissolve the host rock to form caverns. Of particular concern in rapidly growing metropolitan areas that expand in heretofore unexplored regions are the collapse of such caverns. Because Qatar has seen a recent boom in construction, including the planning and development of complete new sub-sections of metropolitan areas, the development areas need to be investigated for the presence of karst to determine their suitability for the planned project. We present a suite of seismic techniques applied to a controlled experiment to detect, locate and estimate the size of a karst analog in form of a man-made water shaft on the campus of Qatar University, Doha, Qatar. Seismic waves are well suited for karst detection and characterization. Voids represent high-contrast seismic objects that exhibit strong responses due to incident seismic waves. However, the complex geometry of karst, including shape and size, makes their imaging nontrivial. While karst detection can be reduced to the simple problem of detecting an anomaly, karst characterization can be complicated by the 3D nature of the problem of unknown scale, where irregular surfaces can generate diffracted waves of different kind. In our presentation, we employ a variety of seismic techniques to demonstrate the detection and characterization of a vertical water collection shaft analyzing the phase, amplitude and spectral information of seismic waves that have been scattered by the object. We use the reduction in seismic wave amplitudes and the delay in phase arrival times in the geometrical shadow of the vertical shaft to independently detect and locate the object in space. Additionally, we use narrow band-pass filtered data combining two orthogonal transmission surveys

  11. Classification of high resolution remote sensing image based on geo-ontology and conditional random fields

    Science.gov (United States)

    Hong, Liang

    2013-10-01

    The availability of high spatial resolution remote sensing data provides new opportunities for urban land-cover classification. More geometric details can be observed in the high resolution remote sensing image, Also Ground objects in the high resolution remote sensing image have displayed rich texture, structure, shape and hierarchical semantic characters. More landscape elements are represented by a small group of pixels. Recently years, the an object-based remote sensing analysis methodology is widely accepted and applied in high resolution remote sensing image processing. The classification method based on Geo-ontology and conditional random fields is presented in this paper. The proposed method is made up of four blocks: (1) the hierarchical ground objects semantic framework is constructed based on geoontology; (2) segmentation by mean-shift algorithm, which image objects are generated. And the mean-shift method is to get boundary preserved and spectrally homogeneous over-segmentation regions ;(3) the relations between the hierarchical ground objects semantic and over-segmentation regions are defined based on conditional random fields framework ;(4) the hierarchical classification results are obtained based on geo-ontology and conditional random fields. Finally, high-resolution remote sensed image data -GeoEye, is used to testify the performance of the presented method. And the experimental results have shown the superiority of this method to the eCognition method both on the effectively and accuracy, which implies it is suitable for the classification of high resolution remote sensing image.

  12. Application of Convolutional Neural Network in Classification of High Resolution Agricultural Remote Sensing Images

    Science.gov (United States)

    Yao, C.; Zhang, Y.; Zhang, Y.; Liu, H.

    2017-09-01

    With the rapid development of Precision Agriculture (PA) promoted by high-resolution remote sensing, it makes significant sense in management and estimation of agriculture through crop classification of high-resolution remote sensing image. Due to the complex and fragmentation of the features and the surroundings in the circumstance of high-resolution, the accuracy of the traditional classification methods has not been able to meet the standard of agricultural problems. In this case, this paper proposed a classification method for high-resolution agricultural remote sensing images based on convolution neural networks(CNN). For training, a large number of training samples were produced by panchromatic images of GF-1 high-resolution satellite of China. In the experiment, through training and testing on the CNN under the toolbox of deep learning by MATLAB, the crop classification finally got the correct rate of 99.66 % after the gradual optimization of adjusting parameter during training. Through improving the accuracy of image classification and image recognition, the applications of CNN provide a reference value for the field of remote sensing in PA.

  13. APPLICATION OF CONVOLUTIONAL NEURAL NETWORK IN CLASSIFICATION OF HIGH RESOLUTION AGRICULTURAL REMOTE SENSING IMAGES

    Directory of Open Access Journals (Sweden)

    C. Yao

    2017-09-01

    Full Text Available With the rapid development of Precision Agriculture (PA promoted by high-resolution remote sensing, it makes significant sense in management and estimation of agriculture through crop classification of high-resolution remote sensing image. Due to the complex and fragmentation of the features and the surroundings in the circumstance of high-resolution, the accuracy of the traditional classification methods has not been able to meet the standard of agricultural problems. In this case, this paper proposed a classification method for high-resolution agricultural remote sensing images based on convolution neural networks(CNN. For training, a large number of training samples were produced by panchromatic images of GF-1 high-resolution satellite of China. In the experiment, through training and testing on the CNN under the toolbox of deep learning by MATLAB, the crop classification finally got the correct rate of 99.66 % after the gradual optimization of adjusting parameter during training. Through improving the accuracy of image classification and image recognition, the applications of CNN provide a reference value for the field of remote sensing in PA.

  14. High-resolution two-dimensional image upconversion of incoherent light

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Pedersen, Christian; Tidemand-Lichtenberg, Peter

    2010-01-01

    We consider a technique for high-resolution image upconversion of thermal light. Experimentally, we demonstrate cw upconversion with a resolution of more than 200 × 1000 pixels of thermally illuminated objects. This is the first demonstration (to our knowledge) of high-resolution cw image...... upconversion. The upconversion method promises an alternative route to high-quantum-efficiency all-optical imaging in the mid-IR wavelength region and beyond using standard CCD cameras. A particular advantage of CCD cameras compared to state-of-the-art thermal cameras is the possibility to tailor and tune...

  15. High-resolution MR imaging of talar osteochondral lesions with new classification

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, James Francis; Lau, Domily Ting Yi; Yeung, David Ka Wai [Prince of Wales Hospital, Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Shatin, NT (China); Wong, Margaret Wan Nar [Prince of Wales Hospital, Chinese University of Hong Kong, Department of Orthopaedics and Traumatology, Shatin (China)

    2012-04-15

    Retrospective review of high-resolution MR imaging features of talar dome osteochondral lesions and development of new classification system based on these features. Over the past 7 years, 70 osteochondral lesions of the talar dome from 70 patients (49 males, 21 females, mean age 42 years, range 15-62 years) underwent high-resolution MR imaging with a microscopy coil at 1.5 T. Sixty-one (87%) of 70 lesions were located on the medial central aspect and ten (13%) lesions were located on the lateral central aspect of the talar dome. Features evaluated included cartilage fracture, osteochondral junction separation, subchondral bone collapse, bone:bone separation, and marrow change. Based on these findings, a new five-part grading system was developed. Signal-to-noise characteristics of microscopy coil imaging at 1.5 T were compared to dedicated ankle coil imaging at 3 T. Microscopy coil imaging at 1.5 T yielded 20% better signal-to-noise characteristics than ankle coil imaging at 3 T. High-resolution MR revealed that osteochondral junction separation, due to focal collapse of the subchondral bone, was a common feature, being present in 28 (45%) of 61 medial central osteochondral lesions. Reparative cartilage hypertrophy and bone:bone separation in the absence of cartilage fracture were also common findings. Complete osteochondral separation was uncommon. A new five-part grading system incorporating features revealed by high-resolution MR imaging was developed. High-resolution MRI reveals clinically pertinent features of talar osteochondral lesions, which should help comprehension of symptomatology and enhance clinical decision-making. These features were incorporated in a new MR-based grading system. Whenever possible, symptomatic talar osteochondral lesions should be assessed by high-resolution MR imaging. (orig.)

  16. High-resolution MR imaging of talar osteochondral lesions with new classification

    International Nuclear Information System (INIS)

    Griffith, James Francis; Lau, Domily Ting Yi; Yeung, David Ka Wai; Wong, Margaret Wan Nar

    2012-01-01

    Retrospective review of high-resolution MR imaging features of talar dome osteochondral lesions and development of new classification system based on these features. Over the past 7 years, 70 osteochondral lesions of the talar dome from 70 patients (49 males, 21 females, mean age 42 years, range 15-62 years) underwent high-resolution MR imaging with a microscopy coil at 1.5 T. Sixty-one (87%) of 70 lesions were located on the medial central aspect and ten (13%) lesions were located on the lateral central aspect of the talar dome. Features evaluated included cartilage fracture, osteochondral junction separation, subchondral bone collapse, bone:bone separation, and marrow change. Based on these findings, a new five-part grading system was developed. Signal-to-noise characteristics of microscopy coil imaging at 1.5 T were compared to dedicated ankle coil imaging at 3 T. Microscopy coil imaging at 1.5 T yielded 20% better signal-to-noise characteristics than ankle coil imaging at 3 T. High-resolution MR revealed that osteochondral junction separation, due to focal collapse of the subchondral bone, was a common feature, being present in 28 (45%) of 61 medial central osteochondral lesions. Reparative cartilage hypertrophy and bone:bone separation in the absence of cartilage fracture were also common findings. Complete osteochondral separation was uncommon. A new five-part grading system incorporating features revealed by high-resolution MR imaging was developed. High-resolution MRI reveals clinically pertinent features of talar osteochondral lesions, which should help comprehension of symptomatology and enhance clinical decision-making. These features were incorporated in a new MR-based grading system. Whenever possible, symptomatic talar osteochondral lesions should be assessed by high-resolution MR imaging. (orig.)

  17. High Resolution Radar Imaging using Coherent MultiBand Processing Techniques

    NARCIS (Netherlands)

    Dorp, Ph. van; Ebeling, R.P.; Huizing, A.G.

    2010-01-01

    High resolution radar imaging techniques can be used in ballistic missile defence systems to determine the type of ballistic missile during the boost phase (threat typing) and to discriminate different parts of a ballistic missile after the boost phase. The applied radar imaging technique is 2D

  18. High-resolution wavefront shaping with a photonic crystal fiber for multimode fiber imaging

    NARCIS (Netherlands)

    Amitonova, L. V.; Descloux, A.; Petschulat, J.; Frosz, M. H.; Ahmed, G.; Babic, F.; Jiang, X.; Mosk, A. P.|info:eu-repo/dai/nl/186344686; Russell, P. S. J.; Pinkse, P.W.H.

    2016-01-01

    We demonstrate that a high-numerical-aperture photonic crystal fiber allows lensless focusing at an unparalleled res- olution by complex wavefront shaping. This paves the way toward high-resolution imaging exceeding the capabilities of imaging with multi-core single-mode optical fibers. We analyze

  19. High-resolution wavefront shaping with a photonic crystal fiber for multimode fiber imaging

    NARCIS (Netherlands)

    Amitonova, Lyubov; Descloux, Adrien; Petschulat, Joerg; Frosz, Michael H.; Ahmed, Goran; Babic, Fehim; Mosk, Allard; Russell, Philip St.J.; Pinkse, Pepijn Willemszoon Harry

    2016-01-01

    We demonstrate that a high-numerical-aperture photonic crystal fiber allows lensless focusing at an unparalleled resolution by complex wavefront shaping. This paves the way toward high-resolution imaging exceeding the capabilities of imaging with multi-core single-mode optical fibers. We analyze the

  20. Super-Resolution Reconstruction of High-Resolution Satellite ZY-3 TLC Images

    Science.gov (United States)

    Li, Lin; Wang, Wei; Luo, Heng; Ying, Shen

    2017-01-01

    Super-resolution (SR) image reconstruction is a technique used to recover a high-resolution image using the cumulative information provided by several low-resolution images. With the help of SR techniques, satellite remotely sensed images can be combined to achieve a higher-resolution image, which is especially useful for a two- or three-line camera satellite, e.g., the ZY-3 high-resolution Three Line Camera (TLC) satellite. In this paper, we introduce the application of the SR reconstruction method, including motion estimation and the robust super-resolution technique, to ZY-3 TLC images. The results show that SR reconstruction can significantly improve both the resolution and image quality of ZY-3 TLC images. PMID:28481287

  1. Super-Resolution Reconstruction of High-Resolution Satellite ZY-3 TLC Images

    Directory of Open Access Journals (Sweden)

    Lin Li

    2017-05-01

    Full Text Available Super-resolution (SR image reconstruction is a technique used to recover a high-resolution image using the cumulative information provided by several low-resolution images. With the help of SR techniques, satellite remotely sensed images can be combined to achieve a higher-resolution image, which is especially useful for a two- or three-line camera satellite, e.g., the ZY-3 high-resolution Three Line Camera (TLC satellite. In this paper, we introduce the application of the SR reconstruction method, including motion estimation and the robust super-resolution technique, to ZY-3 TLC images. The results show that SR reconstruction can significantly improve both the resolution and image quality of ZY-3 TLC images.

  2. Super-Resolution Reconstruction of High-Resolution Satellite ZY-3 TLC Images.

    Science.gov (United States)

    Li, Lin; Wang, Wei; Luo, Heng; Ying, Shen

    2017-05-07

    Super-resolution (SR) image reconstruction is a technique used to recover a high-resolution image using the cumulative information provided by several low-resolution images. With the help of SR techniques, satellite remotely sensed images can be combined to achieve a higher-resolution image, which is especially useful for a two- or three-line camera satellite, e.g., the ZY-3 high-resolution Three Line Camera (TLC) satellite. In this paper, we introduce the application of the SR reconstruction method, including motion estimation and the robust super-resolution technique, to ZY-3 TLC images. The results show that SR reconstruction can significantly improve both the resolution and image quality of ZY-3 TLC images.

  3. High-resolution land/ice imaging using Seasat scatterometer measurements

    Science.gov (United States)

    Long, D. G.; Whiting, P. T.; Hardin, P. J.

    1992-01-01

    A new method for obtaining high-resolution images (to 4 km) of the land backscatter from low-resolution Seasat-A scatterometer (SASS) measurements is introduced. The method utilizes the measurement cell overlap in multiple spacecraft passes over the region of interest and signal processing techniques to generate high-resolution images of the radar backscatter. The overlap is exploited to estimate the underlying high-resolution surface radar backscatter characteristics using a robust multivariate image reconstruction algorithm. The algorithm has been designed to operate in the high-noise environment typical of scatterometer measurements. The ultimate resolution obtainable is a function of the number of measurements and the measurement overlap. Sample results based on SASS data are provided.

  4. Automatic cloud-free image generation from high-resolution multitemporal imagery

    Science.gov (United States)

    Han, Youkyung; Bovolo, Francesca; Lee, Won Hee

    2017-04-01

    The aim of this paper is to document the automatic reconstruction of clouds and their cast shadows for the generation of spontaneous cloud-free images from high-resolution multitemporal images. To apply the proposed technique, a cloud-free reference image, which has the same position as a target image acquired at a different time, is required. First, the cloud region in the target image is detected based on integration of thick and peripheral cloud candidate regions. Next, the detected cloud region is restored using the pixel values of the target image by considering their location relative to the reference images. Finally, the pixel values of the restored image are separately normalized to the values of the reference image to generate a natural-looking cloud-free image. Multitemporal KOMPSAT-2 high-resolution images are used to construct study sites for evaluation of the proposed method in diverse cloud-cover cases. The experimental results show that the proposed method can automatically generate cloud-free images from high-resolution multitemporal images with reasonable qualitative and quantitative performance.

  5. High-resolution storage phosphor imaging of the chest: Comparison with conventional screen-film systems

    International Nuclear Information System (INIS)

    Fuhrman, C.R.; Good, B.; Feist, J.; Gur, D.; Darby, J.

    1987-01-01

    An experimental high-resolution storage phosphor imaging system (Eastman Kodak) has been used to evaluate the image quality and impact on diagnostic interpretation of storage phosphor images relative to conventional screen-film images of the same patients. The elements of the system include a high-resolution laser scanner (4K X 5K X 12 bit); an image processing system; and a high-resolution (4K X 5K X 12 bit) laser printer. Each case was digitally printed onto film in two different formats: a full-size (14 X 14-inch) and a half-size format of four processed, minified images (7 X 7-inches each). The multiformat image includes an original, an unsharp-masked, a reversed (black bone) unsharp-masked, and a high-contrast unsharp-masked image. The results of this preliminary study (11 cases, eight readers) clearly indicate that after minimal adjustment, radiologists do not object to making diagnoses from minified images. Unsharp masked images were considered preferable to unprocessed images, and processed storage phosphor images were rated significantly better than conventional film images

  6. Isotope specific resolution recovery image reconstruction in high resolution PET imaging.

    Science.gov (United States)

    Kotasidis, Fotis A; Angelis, Georgios I; Anton-Rodriguez, Jose; Matthews, Julian C; Reader, Andrew J; Zaidi, Habib

    2014-05-01

    Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution recovery image reconstruction. The

  7. Isotope specific resolution recovery image reconstruction in high resolution PET imaging

    International Nuclear Information System (INIS)

    Kotasidis, Fotis A.; Angelis, Georgios I.; Anton-Rodriguez, Jose; Matthews, Julian C.; Reader, Andrew J.; Zaidi, Habib

    2014-01-01

    Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution

  8. Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yao Dezhong [School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu City, 610054, Sichuan Province (China); He Bin [The University of Illinois at Chicago, IL (United States)

    2003-11-07

    In high-resolution EEG imaging, both equivalent dipole layer (EDL) and equivalent charge layer (ECL) assumed to be located just above the cortical surface have been proposed as high-resolution imaging modalities or as intermediate steps to estimate the epicortical potential. Presented here are the equivalent physical models of these two equivalent source layers (ESL) which show that the strength of EDL is proportional to the surface potential of the layer when the outside of the layer is filled with an insulator, and that the strength of ECL is the normal current of the layer when the outside is filled with a perfect conductor. Based on these equivalent physical models, closed solutions of ECL and EDL corresponding to a dipole enclosed by a spherical layer are given. These results provide the theoretical basis of ESL applications in high-resolution EEG mapping.

  9. Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging.

    Science.gov (United States)

    Yao, Dezhong; He, Bin

    2003-11-07

    In high-resolution EEG imaging, both equivalent dipole layer (EDL) and equivalent charge layer (ECL) assumed to be located just above the cortical surface have been proposed as high-resolution imaging modalities or as intermediate steps to estimate the epicortical potential. Presented here are the equivalent physical models of these two equivalent source layers (ESL) which show that the strength of EDL is proportional to the surface potential of the layer when the outside of the layer is filled with an insulator, and that the strength of ECL is the normal current of the layer when the outside is filled with a perfect conductor. Based on these equivalent physical models, closed solutions of ECL and EDL corresponding to a dipole enclosed by a spherical layer are given. These results provide the theoretical basis of ESL applications in high-resolution EEG mapping.

  10. Multi-Scale Analysis of Very High Resolution Satellite Images Using Unsupervised Techniques

    Directory of Open Access Journals (Sweden)

    Jérémie Sublime

    2017-05-01

    Full Text Available This article is concerned with the use of unsupervised methods to process very high resolution satellite images with minimal or little human intervention. In a context where more and more complex and very high resolution satellite images are available, it has become increasingly difficult to propose learning sets for supervised algorithms to process such data and even more complicated to process them manually. Within this context, in this article we propose a fully unsupervised step by step method to process very high resolution images, making it possible to link clusters to the land cover classes of interest. For each step, we discuss the various challenges and state of the art algorithms to make the full process as efficient as possible. In particular, one of the main contributions of this article comes in the form of a multi-scale analysis clustering algorithm that we use during the processing of the image segments. Our proposed methods are tested on a very high resolution image (Pléiades of the urban area around the French city of Strasbourg and show relevant results at each step of the process.

  11. Lensless high-resolution photoacoustic imaging scanner for in vivo skin imaging

    Science.gov (United States)

    Ida, Taiichiro; Iwazaki, Hideaki; Omuro, Toshiyuki; Kawaguchi, Yasushi; Tsunoi, Yasuyuki; Kawauchi, Satoko; Sato, Shunichi

    2018-02-01

    We previously launched a high-resolution photoacoustic (PA) imaging scanner based on a unique lensless design for in vivo skin imaging. The design, imaging algorithm and characteristics of the system are described in this paper. Neither an optical lens nor an acoustic lens is used in the system. In the imaging head, four sensor elements are arranged quadrilaterally, and by checking the phase differences for PA waves detected with these four sensors, a set of PA signals only originating from a chromophore located on the sensor center axis is extracted for constructing an image. A phantom study using a carbon fiber showed a depth-independent horizontal resolution of 84.0 ± 3.5 µm, and the scan direction-dependent variation of PA signals was about ± 20%. We then performed imaging of vasculature phantoms: patterns of red ink lines with widths of 100 or 200 μm formed in an acrylic block co-polymer. The patterns were visualized with high contrast, showing the capability for imaging arterioles and venues in the skin. Vasculatures in rat burn models and healthy human skin were also clearly visualized in vivo.

  12. HIGH-RESOLUTION TOPOGRAPHY OF MERCURY FROM MESSENGER ORBITAL STEREO IMAGING – THE SOUTHERN HEMISPHERE QUADRANGLES

    Directory of Open Access Journals (Sweden)

    F. Preusker

    2018-04-01

    Full Text Available We produce high-resolution (222 m/grid element Digital Terrain Models (DTMs for Mercury using stereo images from the MESSENGER orbital mission. We have developed a scheme to process large numbers, typically more than 6000, images by photogrammetric techniques, which include, multiple image matching, pyramid strategy, and bundle block adjustments. In this paper, we present models for map quadrangles of the southern hemisphere H11, H12, H13, and H14.

  13. Advances in high-resolution imaging--techniques for three-dimensional imaging of cellular structures.

    Science.gov (United States)

    Lidke, Diane S; Lidke, Keith A

    2012-06-01

    A fundamental goal in biology is to determine how cellular organization is coupled to function. To achieve this goal, a better understanding of organelle composition and structure is needed. Although visualization of cellular organelles using fluorescence or electron microscopy (EM) has become a common tool for the cell biologist, recent advances are providing a clearer picture of the cell than ever before. In particular, advanced light-microscopy techniques are achieving resolutions below the diffraction limit and EM tomography provides high-resolution three-dimensional (3D) images of cellular structures. The ability to perform both fluorescence and electron microscopy on the same sample (correlative light and electron microscopy, CLEM) makes it possible to identify where a fluorescently labeled protein is located with respect to organelle structures visualized by EM. Here, we review the current state of the art in 3D biological imaging techniques with a focus on recent advances in electron microscopy and fluorescence super-resolution techniques.

  14. High-resolution imaging optomechatronics for precise liquid crystal display module bonding automated optical inspection

    Science.gov (United States)

    Ni, Guangming; Liu, Lin; Zhang, Jing; Liu, Juanxiu; Liu, Yong

    2018-01-01

    With the development of the liquid crystal display (LCD) module industry, LCD modules become more and more precise with larger sizes, which demands harsh imaging requirements for automated optical inspection (AOI). Here, we report a high-resolution and clearly focused imaging optomechatronics for precise LCD module bonding AOI inspection. It first presents and achieves high-resolution imaging for LCD module bonding AOI inspection using a line scan camera (LSC) triggered by a linear optical encoder, self-adaptive focusing for the whole large imaging region using LSC, and a laser displacement sensor, which reduces the requirements of machining, assembly, and motion control of AOI devices. Results show that this system can directly achieve clearly focused imaging for AOI inspection of large LCD module bonding with 0.8 μm image resolution, 2.65-mm scan imaging width, and no limited imaging width theoretically. All of these are significant for AOI inspection in the LCD module industry and other fields that require imaging large regions with high resolution.

  15. Origin of high-resolution IETS-STM images of organic molecules with functionalized tips

    Czech Academy of Sciences Publication Activity Database

    Hapala, Prokop; Temirov, R.; Tautz, F.S.; Jelínek, Pavel

    2014-01-01

    Roč. 113, č. 22 (2014), "226101-1"-"226101-5" ISSN 0031-9007 R&D Projects: GA ČR(CZ) GC14-16963J Institutional support: RVO:68378271 Keywords : IETS * AFM * STM * high resolution imaging Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.512, year: 2014

  16. 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

  17. High-resolution satellite image segmentation using Hölder exponents

    Indian Academy of Sciences (India)

    1Regional Remote Sensing Service Centre, Indian Space Research Organization, IIT Campus,. Kharagpur 721 ... The watershed segmentation methods (Vincent .... it does not require any prior information about the pixel intensity. This work attempts to describe the textures of high-resolution images using Hölder exponent.

  18. Segmentation of thin corrugated layers in high-resolution OCT images

    NARCIS (Netherlands)

    Callewaert, T.W.J.; Dik, J.; Kalkman, J.

    2017-01-01

    In this paper we present a novel method for the segmentation of thin corrugated layers in high resolution optical coherence tomography (OCT) images. First, we make an initial segmentation, for example with graph based segmentation that, for highly corrugated interfaces, leads to many segmentation

  19. Investigations of High Resolution Imaging through the Earth’s Atmosphere Using Speckle Interferometry.

    Science.gov (United States)

    1987-03-15

    ELEMENT NO. NO. NO. NO. 11. TITLE rinclude Security Clasification ) 611 2311 G3 DC Investigations of High Resolution Imaging 12. PERSONAL AUTHOR(S) E. Keith...during the observation. 304 ~~r P -,r r V _ _ _ __. .. . _ support the secondaries, are relatively long steel tubes whose lengths vary causing a

  20. Multisensor Fusion of Landsat Images for High-Resolution Thermal Infrared Images Using Sparse Representations

    Directory of Open Access Journals (Sweden)

    Hong Sung Jin

    2017-01-01

    Full Text Available Land surface temperature (LST is an important parameter in the analysis of climate and human-environment interactions. Landsat Earth observation satellite data including a thermal band have been used for environmental research and applications; however, the spatial resolution of this thermal band is relatively low. This study investigates an efficient method of fusing Landsat panchromatic and thermal infrared images using a sparse representation (SR technique. The application of SR is used for the estimation of missing details of the available thermal infrared (TIR image to enhance its spatial features. First, we propose a method of building a proper dictionary considering the spatial resolution of the original thermal image. Second, a sparse representation relation between low- and high-resolution images is constructed in terms of the Landsat spectral response. We then compare the fused images created with different sampling factors and patch sizes. The results of both qualitative and quantitative evaluation show that the proposed method improves spatial resolution and preserves the thermal properties of basic LST data for use with environmental problems.

  1. High resolution MR perfusion imaging of the kidneys at 3 tesla without administration of contrast media

    International Nuclear Information System (INIS)

    Boss, A.; Martirosian, P.; Graf, H.; Claussen, C.D.; Schlemmer, H.P.; Schick, F.

    2005-01-01

    Purpose: The feasibility of high-resolution arterial spin labeling (ASL) perfusion imaging of the kidneys was tested and proven at 3 Tesla using a flow-sensitive alternating inversion recovery (FAIR) true fast imaging in steady precession (TrueFISP) technique. Materials and methods: Kidney perfusion maps of six healthy volunteers and two patients were acquired using a clinical 3-Tesla whole-body scanner. An ASL sequence with FAIR spin preparation and a TrueFISP signal detection strategy was adapted for high-resolution perfusion imaging of the kidneys at 3 Tesla. To avoid banding artifacts in TrueFISP images, which are generally prominent at 3 Tesla, a frequency scout was implemented. Perfusion maps with an in-plane resolution of 1.5 mm were recorded in transverse and coronal orientation. For fast mapping of whole-kidney perfusion, an in-plane resolution of 2 mm was applied. Results: In all volunteers and patients, high-resolution perfusion images with excellent image quality were able to be obtained in a measuring time of approximately 10 minutes. The whole kidney was able to be mapped with good image quality in less than 10 minutes. For all slices, a suitable frequency offset made it possible to reproduce the kidneys without TrueFISP artifacts. Perfusion values of the renal cortex ranged from 250 ml/100 g/min up to 400 ml/100 g/min (mean cortical perfusion right kidney 316±43, left 336±40). (orig.)

  2. High resolution quantitative phase imaging of live cells with constrained optimization approach

    Science.gov (United States)

    Pandiyan, Vimal Prabhu; Khare, Kedar; John, Renu

    2016-03-01

    Quantitative phase imaging (QPI) aims at studying weakly scattering and absorbing biological specimens with subwavelength accuracy without any external staining mechanisms. Use of a reference beam at an angle is one of the necessary criteria for recording of high resolution holograms in most of the interferometric methods used for quantitative phase imaging. The spatial separation of the dc and twin images is decided by the reference beam angle and Fourier-filtered reconstructed image will have a very poor resolution if hologram is recorded below a minimum reference angle condition. However, it is always inconvenient to have a large reference beam angle while performing high resolution microscopy of live cells and biological specimens with nanometric features. In this paper, we treat reconstruction of digital holographic microscopy images as a constrained optimization problem with smoothness constraint in order to recover only complex object field in hologram plane even with overlapping dc and twin image terms. We solve this optimization problem by gradient descent approach iteratively and the smoothness constraint is implemented by spatial averaging with appropriate size. This approach will give excellent high resolution image recovery compared to Fourier filtering while keeping a very small reference angle. We demonstrate this approach on digital holographic microscopy of live cells by recovering the quantitative phase of live cells from a hologram recorded with nearly zero reference angle.

  3. MULTI-SCALE SEGMENTATION OF HIGH RESOLUTION REMOTE SENSING IMAGES BY INTEGRATING MULTIPLE FEATURES

    Directory of Open Access Journals (Sweden)

    Y. Di

    2017-05-01

    Full Text Available Most of multi-scale segmentation algorithms are not aiming at high resolution remote sensing images and have difficulty to communicate and use layers’ information. In view of them, we proposes a method of multi-scale segmentation of high resolution remote sensing images by integrating multiple features. First, Canny operator is used to extract edge information, and then band weighted distance function is built to obtain the edge weight. According to the criterion, the initial segmentation objects of color images can be gained by Kruskal minimum spanning tree algorithm. Finally segmentation images are got by the adaptive rule of Mumford–Shah region merging combination with spectral and texture information. The proposed method is evaluated precisely using analog images and ZY-3 satellite images through quantitative and qualitative analysis. The experimental results show that the multi-scale segmentation of high resolution remote sensing images by integrating multiple features outperformed the software eCognition fractal network evolution algorithm (highest-resolution network evolution that FNEA on the accuracy and slightly inferior to FNEA on the efficiency.

  4. High-resolution MR imaging of the inner ear. Usefulness in cochlear implants

    Energy Technology Data Exchange (ETDEWEB)

    Kumakawa, Kozo

    1988-09-01

    The author investigated high-resolution MR imaging (MRI) of the inner ear and evaluated its usefulness in the selection of patients for cochlear implants. MRI was performed with a 1.5 T unit with the use of the head coil. The minimum thickness of the sections was 2.5 mm. T1- and T2-weighted images were obtained. The matrix size was 256 x 256, and the field of view was 15 cm. ECG-gating was introduced to eliminate motion artifacts. T2-weighted images could clearly delineate details of liquid containing labyrinth structures, including the cochlea, the vestible, the semicircular canals, and the internal auditory canal. With the proper use of T1 and T2 sequences, tissue characterization between lymph fluid and soft tissue could be obtained. This point was considered to be one of the greatest advantages of MRI over high-resolution CT in the diagnosis of inner ear disorders. The head coil technique seems to be superior to the surface coil technique in that it can generate homogeneous signal intensity, and therefore visual comparison of cochlea signals of both sides is possible under the same conditions. The author concluded that high-resolution MRI of the inner ear is useful for the preoperative assessment of cochlear implant candidates in order to rule out soft tissue occlusion of the cochlea, which cannot be diagnosed even by high-resolution CT.

  5. Gas scintillation glass GEM detector for high-resolution X-ray imaging and CT

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, T., E-mail: fujiwara-t@aist.go.jp [Research Institute for Measurement and Analytical Instrumentation, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Mitsuya, Y. [Nuclear Professional School, The University of Tokyo, Tokai, Naka, Ibaraki 319-1188 (Japan); Fushie, T. [Radiment Lab. Inc., Setagaya, Tokyo 156-0044 (Japan); Murata, K.; Kawamura, A.; Koishikawa, A. [XIT Co., Naruse, Machida, Tokyo 194-0045 (Japan); Toyokawa, H. [Research Institute for Measurement and Analytical Instrumentation, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Takahashi, H. [Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8654 (Japan)

    2017-04-01

    A high-spatial-resolution X-ray-imaging gaseous detector has been developed with a single high-gas-gain glass gas electron multiplier (G-GEM), scintillation gas, and optical camera. High-resolution X-ray imaging of soft elements is performed with a spatial resolution of 281 µm rms and an effective area of 100×100 mm. In addition, high-resolution X-ray 3D computed tomography (CT) is successfully demonstrated with the gaseous detector. It shows high sensitivity to low-energy X-rays, which results in high-contrast radiographs of objects containing elements with low atomic numbers. In addition, the high yield of scintillation light enables fast X-ray imaging, which is an advantage for constructing CT images with low-energy X-rays.

  6. High resolution imaging of the mitral valve in the natural state with 7 Tesla MRI

    OpenAIRE

    Stephens, Sam E.; Liachenko, Serguei; Ingels, Neil B.; Wenk, Jonathan F.; Jensen, Morten O.

    2017-01-01

    Imaging techniques of the mitral valve have improved tremendously during the last decade, but challenges persist. The delicate changes in annulus shape and papillary muscle position throughout the cardiac cycle have significant impact on the stress distribution in the leaflets and chords, thus preservation of anatomically accurate positioning is critical. The aim of this study was to develop an in vitro method and apparatus for obtaining high-resolution 3D MRI images of porcine mitral valves ...

  7. High Resolution Bathymetry Estimation Improvement with Single Image Super-Resolution Algorithm Super-Resolution Forests

    Science.gov (United States)

    2017-01-26

    Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/5514--17-9692 High Resolution Bathymetry Estimation Improvement with Single Image Super... Single Image Super-Resolution Algorithm “Super-Resolution Forests” Dylan Einsidler,* Kristen Nock, Leslie Smith, David Bonanno, Paul Elmore, Warren Wood...release; distribution is unlimited. *Florida Atlantic University, 777 Glades Rd., Boca Raton, FL 33431 11 Leslie N. Smith (202) 767-9532 Using the single

  8. High-Resolution Imaging of K2 Planet Host Stars and the Effect of Stellar Companions

    Science.gov (United States)

    Jasmine Gonzales, Erica; Ciardi, David; Crossfield, Ian; K2 Team

    2018-01-01

    Our K2 planetary candidate follow-up program has obtained high-resolution adaptive optics (AO) imaging of K2 targets in Campaigns 5-8. We observed nearly 200 systems and find that roughly 20% of these systems have nearby (TESS mission. In addition, the pixel size of TESS will be larger than Kepler and thus AO imaging will be even more important to uncovering otherwise unknown compaions contributing to photometric measurements.

  9. A novel strategy to access high resolution DICOM medical images based on JPEG2000 interactive protocol

    Science.gov (United States)

    Tian, Yuan; Cai, Weihua; Sun, Jianyong; Zhang, Jianguo

    2008-03-01

    The demand for sharing medical information has kept rising. However, the transmission and displaying of high resolution medical images are limited if the network has a low transmission speed or the terminal devices have limited resources. In this paper, we present an approach based on JPEG2000 Interactive Protocol (JPIP) to browse high resolution medical images in an efficient way. We designed and implemented an interactive image communication system with client/server architecture and integrated it with Picture Archiving and Communication System (PACS). In our interactive image communication system, the JPIP server works as the middleware between clients and PACS servers. Both desktop clients and wireless mobile clients can browse high resolution images stored in PACS servers via accessing the JPIP server. The client can only make simple requests which identify the resolution, quality and region of interest and download selected portions of the JPEG2000 code-stream instead of downloading and decoding the entire code-stream. After receiving a request from a client, the JPIP server downloads the requested image from the PACS server and then responds the client by sending the appropriate code-stream. We also tested the performance of the JPIP server. The JPIP server runs stably and reliably under heavy load.

  10. A High-resolution Multi-wavelength Simultaneous Imaging System with Solar Adaptive Optics

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Changhui; Zhu, Lei; Gu, Naiting; Rao, Xuejun; Zhang, Lanqiang; Bao, Hua; Kong, Lin; Guo, Youming; Zhong, Libo; Ma, Xue’an; Li, Mei; Wang, Cheng; Zhang, Xiaojun; Fan, Xinlong; Chen, Donghong; Feng, Zhongyi; Wang, Xiaoyun; Wang, Zhiyong, E-mail: gunaiting@ioe.ac.cn [The Key Laboratory on Adaptive Optics, Chinese Academy of Sciences, P.O. Box 350, Shuangliu, Chengdu 610209, Sichuan (China)

    2017-10-01

    A high-resolution multi-wavelength simultaneous imaging system from visible to near-infrared bands with a solar adaptive optics system, in which seven imaging channels, including the G band (430.5 nm), the Na i line (589 nm), the H α line (656.3 nm), the TiO band (705.7 nm), the Ca ii IR line (854.2 nm), the He i line (1083 nm), and the Fe i line (1565.3 nm), are chosen, is developed to image the solar atmosphere from the photosphere layer to the chromosphere layer. To our knowledge, this is the solar high-resolution imaging system with the widest spectral coverage. This system was demonstrated at the 1 m New Vaccum Solar Telescope and the on-sky high-resolution observational results were acquired. In this paper, we will illustrate the design and performance of the imaging system. The calibration and the data reduction of the system are also presented.

  11. INTERACTIVE CHANGE DETECTION USING HIGH RESOLUTION REMOTE SENSING IMAGES BASED ON ACTIVE LEARNING WITH GAUSSIAN PROCESSES

    Directory of Open Access Journals (Sweden)

    H. Ru

    2016-06-01

    Full Text Available Although there have been many studies for change detection, the effective and efficient use of high resolution remote sensing images is still a problem. Conventional supervised methods need lots of annotations to classify the land cover categories and detect their changes. Besides, the training set in supervised methods often has lots of redundant samples without any essential information. In this study, we present a method for interactive change detection using high resolution remote sensing images with active learning to overcome the shortages of existing remote sensing image change detection techniques. In our method, there is no annotation of actual land cover category at the beginning. First, we find a certain number of the most representative objects in unsupervised way. Then, we can detect the change areas from multi-temporal high resolution remote sensing images by active learning with Gaussian processes in an interactive way gradually until the detection results do not change notably. The artificial labelling can be reduced substantially, and a desirable detection result can be obtained in a few iterations. The experiments on Geo-Eye1 and WorldView2 remote sensing images demonstrate the effectiveness and efficiency of our proposed method.

  12. In-utero three dimension high resolution fetal brain diffusion tensor imaging.

    Science.gov (United States)

    Jiang, Shuzhou; Xue, Hui; Counsell, Serena; Anjari, Mustafa; Allsop, Joanna; Rutherford, Mary; Rueckert, Daniel; Hajnal, Joseph V

    2007-01-01

    We present a methodology to achieve 3D high resolution in-utero fetal brain DTI that shows excellent ADC as well as promising FA maps. After continuous DTI scanning to acquire a repeated series of parallel slices with 15 diffusion directions, image registration is used to realign the images to correct for fetal motion. Once aligned, the diffusion images are treated as irregularly sampled data where each voxel is associated with an appropriately rotated diffusion direction, and used to estimate the diffusion tensor on a regular grid. The method has been tested successful on eight fetuses and has been validated on adults imaged at 1.5T.

  13. BEMD-based high resolution image fusion for land cover classification: A case study in Guilin

    Science.gov (United States)

    Li, Lei; Liu, Guang; Jin, Qingwen; He, Chengxin; Huang, Yuqing; Yao, Yuefeng

    2016-11-01

    Analysis of image texture feature can help to reduce the adverse effects of the condition that same object but different band or same band but different object. Therefore, if it can add and highlight the texture information to the remote sensing image, it will be very helpful in the classification of ground objects. In this paper we consider to add SAR image information in classification. Bidimensional empirical mode decomposition (BEMD) has been widely applied to the analysis of non-stationary and non-linear signals. This paper proposes a new method for fusing high resolution SAR and optical image in Guilin area, based on Bidimensional empirical mode decomposition (BEMD) method.

  14. Pyramidal Watershed Segmentation Algorithm for High-Resolution Remote Sensing Images Using Discrete Wavelet Transforms

    Directory of Open Access Journals (Sweden)

    K. Parvathi

    2009-01-01

    Full Text Available The watershed transformation is a useful morphological segmentation tool for a variety of grey-scale images. However, over segmentation and under segmentation have become the key problems for the conventional algorithm. In this paper, an efficient segmentation method for high-resolution remote sensing image analysis is presented. Wavelet analysis is one of the most popular techniques that can be used to detect local intensity variation and hence the wavelet transformation is used to analyze the image. Wavelet transform is applied to the image, producing detail (horizontal, vertical, and diagonal and Approximation coefficients. The image gradient with selective regional minima is estimated with the grey-scale morphology for the Approximation image at a suitable resolution, and then the watershed is applied to the gradient image to avoid over segmentation. The segmented image is projected up to high resolutions using the inverse wavelet transform. The watershed segmentation is applied to small subset size image, demanding less computational time. We have applied our new approach to analyze remote sensing images. The algorithm was implemented in MATLAB. Experimental results demonstrated the method to be effective.

  15. A New Method for Acquisition of High-Resolution Seabed Topography by Matching Seabed Classification Images

    Directory of Open Access Journals (Sweden)

    Jianhu Zhao

    2017-11-01

    Full Text Available The multibeam echo sounders (MBES can acquire accurate positional but low-resolution seabed terrain and images, whereas side scan sonars (SSS can only acquire inaccurate positional but high-resolution seabed images. In this study, a new method for superimposing corrected-positional SSS images on multibeam bathymetric terrain is proposed to obtain high-resolution and accurate-positional seabed topography using traditional MBES and SSS. Three steps, including the normalization by the z-score, sediment classification by the k-means++ algorithm, and denoising processing using morphological operations, are processed for both MBES and SSS images to obtain the corresponding sediment images. Next, a segmented matching method is given based on the common sediment distributions and features of MBES and SSS sediment images. The two kinds of sediment images are matched segmentally using the speeded up robust features algorithm and random sample consensus algorithm. Then, the positions of SSS images are corrected segmentally using thin plate splines based on matching points. Finally, the corrected SSS image is superimposed on MBES bathymetric terrain, based on positional relationship. The proposed method was verified through experiments, and high image resolution and high position accuracy seabed topography were obtained. Moreover, the performances of the method are discussed, and some conclusions are drawn according to the experiments and discussions.

  16. Automated Segmentation of High-Resolution Photospheric Images of Active Regions

    Science.gov (United States)

    Yang, Meng; Tian, Yu; Rao, Changhui

    2018-02-01

    Due to the development of ground-based, large-aperture solar telescopes with adaptive optics (AO) resulting in increasing resolving ability, more accurate sunspot identifications and characterizations are required. In this article, we have developed a set of automated segmentation methods for high-resolution solar photospheric images. Firstly, a local-intensity-clustering level-set method is applied to roughly separate solar granulation and sunspots. Then reinitialization-free level-set evolution is adopted to adjust the boundaries of the photospheric patch; an adaptive intensity threshold is used to discriminate between umbra and penumbra; light bridges are selected according to their regional properties from candidates produced by morphological operations. The proposed method is applied to the solar high-resolution TiO 705.7-nm images taken by the 151-element AO system and Ground-Layer Adaptive Optics prototype system at the 1-m New Vacuum Solar Telescope of the Yunnan Observatory. Experimental results show that the method achieves satisfactory robustness and efficiency with low computational cost on high-resolution images. The method could also be applied to full-disk images, and the calculated sunspot areas correlate well with the data given by the National Oceanic and Atmospheric Administration (NOAA).

  17. A fast and automatic mosaic method for high-resolution satellite images

    Science.gov (United States)

    Chen, Hongshun; He, Hui; Xiao, Hongyu; Huang, Jing

    2015-12-01

    We proposed a fast and fully automatic mosaic method for high-resolution satellite images. First, the overlapped rectangle is computed according to geographical locations of the reference and mosaic images and feature points on both the reference and mosaic images are extracted by a scale-invariant feature transform (SIFT) algorithm only from the overlapped region. Then, the RANSAC method is used to match feature points of both images. Finally, the two images are fused into a seamlessly panoramic image by the simple linear weighted fusion method or other method. The proposed method is implemented in C++ language based on OpenCV and GDAL, and tested by Worldview-2 multispectral images with a spatial resolution of 2 meters. Results show that the proposed method can detect feature points efficiently and mosaic images automatically.

  18. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map

    Directory of Open Access Journals (Sweden)

    Yihua Tan

    2015-09-01

    Full Text Available This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate.

  19. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map.

    Science.gov (United States)

    Tan, Yihua; Li, Qingyun; Li, Yansheng; Tian, Jinwen

    2015-09-11

    This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate.

  20. High-resolution Ceres Low Altitude Mapping Orbit Atlas derived from Dawn Framing Camera images

    Science.gov (United States)

    Roatsch, Th.; Kersten, E.; Matz, K.-D.; Preusker, F.; Scholten, F.; Jaumann, R.; Raymond, C. A.; Russell, C. T.

    2017-06-01

    The Dawn spacecraft Framing Camera (FC) acquired over 31,300 clear filter images of Ceres with a resolution of about 35 m/pxl during the eleven cycles in the Low Altitude Mapping Orbit (LAMO) phase between December 16 2015 and August 8 2016. We ortho-rectified the images from the first four cycles and produced a global, high-resolution, uncontrolled photomosaic of Ceres. This global mosaic is the basis for a high-resolution Ceres atlas that consists of 62 tiles mapped at a scale of 1:250,000. The nomenclature used in this atlas was proposed by the Dawn team and was approved by the International Astronomical Union (IAU). The full atlas is available to the public through the Dawn Geographical Information System (GIS) web page [http://dawngis.dlr.de/atlas] and will become available through the NASA Planetary Data System (PDS) (http://pdssbn.astro.umd.edu/).

  1. Anatomy of the fingers in MR imaging using a high resolution surface coil

    International Nuclear Information System (INIS)

    Maeurer, J.; Mueller, H.F.; Lemke, A.J.; Requardt, R.; Stein, I.; Schedel, H.; Langer, R.; Felix, R.

    1994-01-01

    MR-images of the fingers of twenty healthy volunteers were obtained at a 1,5-T whole-body system with a high resolution coil. Additionally, the fingers of two formalin-fixed anatomical specismen were imaged, fronzen and then subsequently sectioned for anatomic correlation. Measurements were recorded with a slice thickness of 2 mm. A 256x256 matrix and a 2,5 cam fiel of view (FOV) were used resulting in a pixel size of 0,01 mm 2 . Based on the excellent depiction of anatomic detail and contrast resolution high resolution MRI of the fingers enabled identification of osseous and cartilaginous structures, as well as delineation of tendons, ligaments blood-vessels and dermal layers. (orig.) [de

  2. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

    DEFF Research Database (Denmark)

    Makowska, Malgorzata G.; Kuhn, Luise Theil; Cleemann, Lars Nilausen

    2015-01-01

    High material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible...... with any other technique. This paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 ◦C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging...

  3. State-of-the-art of small animal imaging with high-resolution SPECT

    International Nuclear Information System (INIS)

    Nikolaus, S.; Wirrwar, A.; Antke, C.; Kley, K.; Mueller, H.W.

    2005-01-01

    During the recent years, in vivo imaging of small animals using SPECT has become of growing relevance. Along with the development of dedicated high-resolution small animal SPECT cameras, an increasing number of conventional clinical scanners has been equipped with single or multipinhole collimators. This paper reviews the small animal tomographs, which are operating at present and compares their performance characteristics. Furthermore, we describe the in vivo imaging studies, which have been performed so far with the individual scanners and survey current approaches to optimize molecular imaging with small animal SPECT. (orig.)

  4. High resolution neutron imaging of water in the polymer electrolyte fuel cell membrane

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Partha P [Los Alamos National Laboratory; Makundan, Rangachary [Los Alamos National Laboratory; Spendelow, Jacob S [Los Alamos National Laboratory; Borup, Rodney L [Los Alamos National Laboratory; Hussey, D S [NIST; Jacobson, D L [NIST; Arif, M [NIST

    2009-01-01

    Water transport in the ionomeric membrane, typically Nafion{reg_sign}, has profound influence on the performance of the polymer electrolyte fuel cell, in terms of internal resistance and overall water balance. In this work, high resolution neutron imaging of the Nafion{reg_sign} membrane is presented in order to measure water content and through-plane gradients in situ under disparate temperature and humidification conditions.

  5. High resolution computational on-chip imaging of biological samples using sparsity constraint (Conference Presentation)

    Science.gov (United States)

    Rivenson, Yair; Wu, Chris; Wang, Hongda; Zhang, Yibo; Ozcan, Aydogan

    2017-03-01

    Microscopic imaging of biological samples such as pathology slides is one of the standard diagnostic methods for screening various diseases, including cancer. These biological samples are usually imaged using traditional optical microscopy tools; however, the high cost, bulkiness and limited imaging throughput of traditional microscopes partially restrict their deployment in resource-limited settings. In order to mitigate this, we previously demonstrated a cost-effective and compact lens-less on-chip microscopy platform with a wide field-of-view of >20-30 mm^2. The lens-less microscopy platform has shown its effectiveness for imaging of highly connected biological samples, such as pathology slides of various tissue samples and smears, among others. This computational holographic microscope requires a set of super-resolved holograms acquired at multiple sample-to-sensor distances, which are used as input to an iterative phase recovery algorithm and holographic reconstruction process, yielding high-resolution images of the samples in phase and amplitude channels. Here we demonstrate that in order to reconstruct clinically relevant images with high resolution and image contrast, we require less than 50% of the previously reported nominal number of holograms acquired at different sample-to-sensor distances. This is achieved by incorporating a loose sparsity constraint as part of the iterative holographic object reconstruction. We demonstrate the success of this sparsity-based computational lens-less microscopy platform by imaging pathology slides of breast cancer tissue and Papanicolaou (Pap) smears.

  6. RELATIVE ORIENTATION AND MODIFIED PIECEWISE EPIPOLAR RESAMPLING FOR HIGH RESOLUTION SATELLITE IMAGES

    Directory of Open Access Journals (Sweden)

    K. Gong

    2017-05-01

    Full Text Available High resolution, optical satellite sensors are boosted to a new era in the last few years, because satellite stereo images at half meter or even 30cm resolution are available. Nowadays, high resolution satellite image data have been commonly used for Digital Surface Model (DSM generation and 3D reconstruction. It is common that the Rational Polynomial Coefficients (RPCs provided by the vendors have rough precision and there is no ground control information available to refine the RPCs. Therefore, we present two relative orientation methods by using corresponding image points only: the first method will use quasi ground control information, which is generated from the corresponding points and rough RPCs, for the bias-compensation model; the second method will estimate the relative pointing errors on the matching image and remove this error by an affine model. Both methods do not need ground control information and are applied for the entire image. To get very dense point clouds, the Semi-Global Matching (SGM method is an efficient tool. However, before accomplishing the matching process the epipolar constraints are required. In most conditions, satellite images have very large dimensions, contrary to the epipolar geometry generation and image resampling, which is usually carried out in small tiles. This paper also presents a modified piecewise epipolar resampling method for the entire image without tiling. The quality of the proposed relative orientation and epipolar resampling method are evaluated, and finally sub-pixel accuracy has been achieved in our work.

  7. Automatic Near-Real-Time Image Processing Chain for Very High Resolution Optical Satellite Data

    Science.gov (United States)

    Ostir, K.; Cotar, K.; Marsetic, A.; Pehani, P.; Perse, M.; Zaksek, K.; Zaletelj, J.; Rodic, T.

    2015-04-01

    In response to the increasing need for automatic and fast satellite image processing SPACE-SI has developed and implemented a fully automatic image processing chain STORM that performs all processing steps from sensor-corrected optical images (level 1) to web-delivered map-ready images and products without operator's intervention. Initial development was tailored to high resolution RapidEye images, and all crucial and most challenging parts of the planned full processing chain were developed: module for automatic image orthorectification based on a physical sensor model and supported by the algorithm for automatic detection of ground control points (GCPs); atmospheric correction module, topographic corrections module that combines physical approach with Minnaert method and utilizing anisotropic illumination model; and modules for high level products generation. Various parts of the chain were implemented also for WorldView-2, THEOS, Pleiades, SPOT 6, Landsat 5-8, and PROBA-V. Support of full-frame sensor currently in development by SPACE-SI is in plan. The proposed paper focuses on the adaptation of the STORM processing chain to very high resolution multispectral images. The development concentrated on the sub-module for automatic detection of GCPs. The initially implemented two-step algorithm that worked only with rasterized vector roads and delivered GCPs with sub-pixel accuracy for the RapidEye images, was improved with the introduction of a third step: super-fine positioning of each GCP based on a reference raster chip. The added step exploits the high spatial resolution of the reference raster to improve the final matching results and to achieve pixel accuracy also on very high resolution optical satellite data.

  8. Computerized tomography using high resolution X-ray imaging system with a microfocus source

    International Nuclear Information System (INIS)

    Zaprazny, Z.; Korytar, D.; Konopka, P.; Ac, V.; Bielecki, J.

    2011-01-01

    In recent years there is an effort to image an internal structure of an object by using not only conventional 2D X-ray radiography but also using high resolution 3D tomography which is based on reconstruction of multiple 2D projections at various angular positions of the object. We have previously reported [1] the development and basic parameters of a high resolution x-ray imaging system with a microfocus source. We report the recent progress using this high resolution X-ray laboratory system in this work. These first findings show that our system is particularly suitable for light weight and nonmetallic objects such as biological objects, plastics, wood, paper, etc. where phase contrast helps to increase the visibility of the finest structures of the object. Phase-contrast X-ray Computerized Tomography is of our special interest because it is an emerging imaging technique that can be implemented at third generation synchrotron radiation sources and also in laboratory conditions using a microfocus X-ray tube or beam conditioning optics. (authors)

  9. Radiofrequency configuration to facilitate bilateral breast 31P MR spectroscopic imaging and high-resolution MRI at 7 Tesla

    NARCIS (Netherlands)

    van der Velden, Tijl A.; Italiaander, Michel; van der Kemp, Wybe J M; Raaijmakers, AJE; Schmitz, A. M Th; Luijten, Peter R.; Boer, VO; Klomp, DWJ

    2015-01-01

    PURPOSE: High-resolution MRI combined with phospholipid detection may improve breast cancer grading. Currently, configurations are optimized for either high-resolution imaging or 31 P spectroscopy. To be able to perform both imaging as well as spectroscopy in a single session, we integrated a 1 H

  10. Design and fabrication of a passive droplet dispenser for portable high resolution imaging system

    Science.gov (United States)

    Kamal, Tahseen; Watkins, Rachel; Cen, Zijian; Rubinstein, Jaden; Kong, Gary; Lee, Woei Ming

    2017-01-01

    Moldless lens manufacturing techniques using standard droplet dispensing technology often require precise control over pressure to initiate fluid flow and control droplet formation. We have determined a series of interfacial fluid parameters optimised using standard 3D printed tools to extract, dispense and capture a single silicone droplet that is then cured to obtain high quality lenses. The dispensing process relies on the recapitulation of liquid dripping action (Rayleigh-Plateau instability) and the capturing method uses the interplay of gravitational force, capillary forces and liquid pinning to control the droplet shape. The key advantage of the passive lens fabrication approach is rapid scale-up using 3D printing by avoiding complex dispensing tools. We characterise the quality of the lenses fabricated using the passive approach by measuring wavefront aberration and high resolution imaging. The fabricated lenses are then integrated into a portable imaging system; a wearable thimble imaging device with a detachable camera housing, that is constructed for field imaging. This paper provides the full exposition of steps, from lens fabrication to imaging platform, necessary to construct a standalone high resolution imaging system. The simplicity of our methodology can be implemented using a regular desktop 3D printer and commercially available digital imaging systems.

  11. High-resolution acoustic-radiation-force-impulse imaging for assessing corneal sclerosis.

    Science.gov (United States)

    Shih, Cho-Chiang; Huang, Chih-Chung; Zhou, Qifa; Shung, K Kirk

    2013-07-01

    In ophthalmology, detecting the biomechanical properties of the cornea can provide valuable information about various corneal pathologies, including keratoconus and the phototoxic effects of ultraviolet radiation on the cornea. Also, the mechanical properties of the cornea can be used to evaluate the recovery from corneal refractive surgeries. Therefore, noninvasive and high-resolution estimation of the stiffness distribution in the cornea is important in ophthalmic diagnosis. The present study established a method for high-resolution acoustic-radiation-force-impulse (ARFI) imaging based on a dual-frequency confocal transducer in order to obtain a relative stiffness map, which was used to assess corneal sclerosis. An 11-MHz pushing element was used to induce localized displacements of tissue, which were monitored by a 48-MHz imaging element. Since the tissue displacements are directly correlated with the tissue elastic properties, the stiffness distribution in a tiny region of the cornea can be found by a mechanical B/D scan. The experimental system was verified using tissue-mimicking phantoms that included different geometric structures. Ex vivo cornea experiments were carried out using fresh porcine eyeballs. Corneas with localized sclerosis were created artificially by the injection of a formalin solution. The phantom experiments showed that the distributions of stiffness within different phantoms can be recognized clearly using ARFI imaging, and the measured lateral and axial resolutions of this imaging system were 177 and 153 μ m, respectively. The ex vivo experimental results from ARFI imaging showed that a tiny region of localized sclerosis in the cornea could be distinguished. All of the obtained results demonstrate that high-resolution ARFI imaging has considerable potential for the clinical diagnosis of corneal sclerosis.

  12. Registration-based approach for reconstruction of high-resolution in utero fetal MR brain images.

    Science.gov (United States)

    Rousseau, Francois; Glenn, Orit A; Iordanova, Bistra; Rodriguez-Carranza, Claudia; Vigneron, Daniel B; Barkovich, James A; Studholme, Colin

    2006-09-01

    This paper describes a novel approach to forming high-resolution MR images of the human fetal brain. It addresses the key problem of fetal motion by proposing a registration-refined compounding of multiple sets of orthogonal fast two-dimensional MRI slices, which are currently acquired for clinical studies, into a single high-resolution MRI volume. A robust multiresolution slice alignment is applied iteratively to the data to correct motion of the fetus that occurs between two-dimensional acquisitions. This is combined with an intensity correction step and a super-resolution reconstruction step, to form a single high isotropic resolution volume of the fetal brain. Experimental validation on synthetic image data with known motion types and underlying anatomy, together with retrospective application to sets of clinical acquisitions, are included. Results indicate that this method promises a unique route to acquiring high-resolution MRI of the fetal brain in vivo allowing comparable quality to that of neonatal MRI. Such data provide a highly valuable window into the process of normal and abnormal brain development, which is directly applicable in a clinical setting.

  13. High-resolution 3D laser imaging based on tunable fiber array link

    Science.gov (United States)

    Zhao, Sisi; Ruan, Ningjuan; Yang, Song

    2017-10-01

    Airborne photoelectric reconnaissance system with the bore sight down to the ground is an important battlefield situational awareness system, which can be used for reconnaissance and surveillance of complex ground scene. Airborne 3D imaging Lidar system is recognized as the most potential candidates for target detection under the complex background, and is progressing in the directions of high resolution, long distance detection, high sensitivity, low power consumption, high reliability, eye safe and multi-functional. However, the traditional 3D laser imaging system has the disadvantages of lower imaging resolutions because of the small size of the existing detector, and large volume. This paper proposes a high resolution laser 3D imaging technology based on the tunable optical fiber array link. The echo signal is modulated by a tunable optical fiber array link and then transmitted to the focal plane detector. The detector converts the optical signal into electrical signals which is given to the computer. Then, the computer accomplishes the signal calculation and image restoration based on modulation information, and then reconstructs the target image. This paper establishes the mathematical model of tunable optical fiber array signal receiving link, and proposes the simulation and analysis of the affect factors on high density multidimensional point cloud reconstruction.

  14. Myocardial Infarction Area Quantification using High-Resolution SPECT Images in Rats

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Luciano Fonseca Lemos de [Divisão de Cardiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Mejia, Jorge [Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP (Brazil); Carvalho, Eduardo Elias Vieira de; Lataro, Renata Maria; Frassetto, Sarita Nasbine [Divisão de Cardiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Fazan, Rubens Jr.; Salgado, Hélio Cesar [Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Galvis-Alonso, Orfa Yineth [Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP (Brazil); Simões, Marcus Vinícius, E-mail: msimoes@fmrp.usp.br [Divisão de Cardiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2013-07-15

    Imaging techniques enable in vivo sequential assessment of the morphology and function of animal organs in experimental models. We developed a device for high-resolution single photon emission computed tomography (SPECT) imaging based on an adapted pinhole collimator. To determine the accuracy of this system for quantification of myocardial infarct area in rats. Thirteen male Wistar rats (250 g) underwent experimental myocardial infarction by occlusion of the left coronary artery. After 4 weeks, SPECT images were acquired 1.5 hours after intravenous injection of 555 MBq of 99mTc-Sestamibi. The tomographic reconstruction was performed by using specially developed software based on the Maximum Likelihood algorithm. The analysis of the data included the correlation between the area of perfusion defects detected by scintigraphy and extent of myocardial fibrosis assessed by histology. The images showed a high target organ/background ratio with adequate visualization of the left ventricular walls and cavity. All animals presenting infarction areas were correctly identified by the perfusion images. There was no difference of the infarct area as measured by SPECT (21.1 ± 21.2%) and by histology (21.7 ± 22.0%; p=0.45). There was a strong correlation between individual values of the area of infarction measured by these two methods. The developed system presented adequate spatial resolution and high accuracy for the detection and quantification of myocardial infarction areas, consisting in a low cost and versatile option for high-resolution SPECT imaging of small rodents.

  15. Performances of a specific denoising wavelet process for high-resolution gamma imaging

    Science.gov (United States)

    Pousse, Annie; Dornier, Christophe; Parmentier, Michel; Kastler, Bruno; Chavanelle, Jerome

    2004-02-01

    Due to its functional capabilities, gamma imaging is an interesting tool for medical diagnosis. Recent developments lead to improved intrinsic resolution. However this gain is impaired by the poor activity detected and the Poissonian feature of gamma ray emission. High resolution gamma images are grainy. This is a real nuisance for detecting cold nodules in an emitting organ. A specific translation wavelet filter which takes into account the Poissonian feature of noise, has been developed in order to improve the diagnostic capabilities of radioisotopic high resolution images. Monte Carlo simulations of a hot thyroid phantom in which cold spheres, 3-7 mm in diameter, could be included were performed. The loss of activity induced by cold nodules was determined on filtered images by using catchment basins determination. On the original images, only 5-7 mm cold spheres were clearly visible. On filtered images, 3 and 4 mm spheres were put in prominent. The limit of the developed filter is approximately the detection of 3 mm spherical cold nodule in acquisition and activity conditions which mimic a thyroid examination. Furthermore, no disturbing artifacts are generated. It is therefore a powerful tool for detecting small cold nodules in a gamma emitting medium.

  16. High resolution measurement of the velocity profiles of channel flows using the particle image velocimetry technique

    International Nuclear Information System (INIS)

    Nor Azizi Mohamed

    2000-01-01

    The high resolution velocity profiles of a uniform steady channel flow and a flow beneath waves were obtained using the particle image velocimetry (PIV) technique. The velocity profiles for each flow were calculated for both components. It is shown that the profiles obtained are very precise, displaying the point velocities from a few millimeters from the bottom of the channel up to the water surface across the water depth. In the case of the wave-induced flow, the profiles are shown under the respective wave phases and given in a plane representation. High resolution measurement of point velocities in a flow is achievable using PIV and invaluable when applied to a complex flow. (Author)

  17. 3D high-resolution radar imaging of small body interiors

    Science.gov (United States)

    Sava, Paul; Asphaug, Erik

    2017-10-01

    Answering fundamental questions about the origin and evolution of small planetary bodies hinges on our ability to image their interior structure in detail and at high resolution (Asphaug, 2009). We often infer internal structure from surface observations, e.g. that comet 67P/Churyumov-Gerasimenko is a primordial agglomeration of cometesimals (Massironi et al., 2015). However, the interior structure is not easily accessible without systematic imaging using, e.g., radar transmission and reflection data, as suggested by the CONSERT experiment on Rosetta. Interior imaging depends on observations from multiple viewpoints, as in medical tomography.We discuss radar imaging using methodology adapted from terrestrial exploration seismology (Sava et al., 2015). We primarily focus on full wavefield methods that facilitate high quality imaging of small body interiors characterized by complex structure and large contrasts of physical properties. We consider the case of a monostatic system (co-located transmitters and receivers) operated at two frequency bands, centered around 5 and 15 MHz, from a spacecraft in slow polar orbit around a spinning comet nucleus. Assuming that the spin period is significantly (e.g. 5x) faster than the orbital period, this configuration allows repeated views from multiple directions (Safaeinili et al., 2002)Using realistic numerical experiments, we argue that (1) the comet/asteroid imaging problem is intrinsically 3D and conventional SAR methodology does not satisfy imaging, sampling and resolution requirements; (2) imaging at different frequency bands can provide information about internal surfaces (through migration) and internal volumes (through tomography); (3) interior imaging can be accomplished progressively as data are being acquired through successive orbits around the studied object; (4) imaging resolution can go beyond the apparent radar frequency band by deconvolution of the point-spread-function characterizing the imaging system; and (5

  18. Very high resolution 8,002-pixel trilinear color image sensor

    Science.gov (United States)

    Kecskemety, Brent J.; Carducci, Thomas; Ciccarelli, Antonio S.

    2001-02-01

    A very high resolution 8,002-pixel trilinear image sensor is under development to meet customer requirement as they progress toward the next generation graphic arts scanning and industrial inspection systems. High-performance features will include an enhanced color filter scheme providing improved blue and green responsivity; better filter uniformity; lower dark current; improved, uncooled dynamic range to 15 bits; and will provide over 400,000 electrons of charge capacity. This sensor maintains a common optical length to Kodak's current line of long trilinear imagers.

  19. High resolution x-ray and gamma ray imaging using diffraction lenses with mechanically bent crystals

    Science.gov (United States)

    Smither, Robert K [Hinsdale, IL

    2008-12-23

    A method for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation is provided. High quality mechanically bent diffracting crystals of 0.1 mm radial width are used for focusing the radiation and directing the radiation to an array of detectors which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for the use of a multi-component high resolution detector array and for narrow source and detector apertures.

  20. High-Resolution, Quantitative, and Three-Dimensional Coherent Diffractive Imaging with a Tabletop EUV Source

    Science.gov (United States)

    Shanblatt, Elisabeth Rose

    Imaging is a critical tool used across a broad range of applications in science, technology, medicine, and manufacturing. Microscopy, the type of imaging which allows us to access the elusive yet rich world of what is smaller than we can naturally see--makes it possible to observe and design the nano-world of biological, material, and nanofabricated systems. In this thesis, I describe the development of a new type of microscopy that combines two powerful tools: coherent extreme ultraviolet (EUV) light sources produced by high harmonic generation, and ptychographic coherent diffractive imaging. This microscope produces high-resolution, chemically-specific, phase- and amplitude-contrast images with large fields of view on the order of hundreds of microns, while preserving a high spatial resolution on the scale of tens of nanometers. Recently, we extended this new tabletop microscopy technique to image reflective samples, periodic samples, and to image dynamic nano-scale elastic and thermal processes. I will discuss these advances and in particular demonstrate two new capabilities: first, a new imaging technique with high compositionally- and morphologically-sensitive quantitative information, capable of imaging reactions and diffusion at a buried interface. This capability will open up a new, exquisitely sensitive layer-by-layer imaging that has many applications in nanoscience and nanotechnology, including surface and materials science and metrology. Secondly, I will demonstrate imaging of a thick sample in three dimensions. By accounting for diffraction within a thick sample, it is possible to obtain high-resolution three-dimensional images of biological and meta-material samples non-invasively, and without the use of staining or labeling.

  1. Feasibility analysis of high resolution tissue image registration using 3-D synthetic data

    Directory of Open Access Journals (Sweden)

    Yachna Sharma

    2011-01-01

    Full Text Available Background: Registration of high-resolution tissue images is a critical step in the 3D analysis of protein expression. Because the distance between images (~4-5μm thickness of a tissue section is nearly the size of the objects of interest (~10-20μm cancer cell nucleus, a given object is often not present in both of two adjacent images. Without consistent correspondence of objects between images, registration becomes a difficult task. This work assesses the feasibility of current registration techniques for such images. Methods: We generated high resolution synthetic 3-D image data sets emulating the constraints in real data. We applied multiple registration methods to the synthetic image data sets and assessed the registration performance of three techniques (i.e., mutual information (MI, kernel density estimate (KDE method [1], and principal component analysis (PCA at various slice thicknesses (with increments of 1μm in order to quantify the limitations of each method. Results: Our analysis shows that PCA, when combined with the KDE method based on nuclei centers, aligns images corresponding to 5μm thick sections with acceptable accuracy. We also note that registration error increases rapidly with increasing distance between images, and that the choice of feature points which are conserved between slices improves performance. Conclusions: We used simulation to help select appropriate features and methods for image registration by estimating best-case-scenario errors for given data constraints in histological images. The results of this study suggest that much of the difficulty of stained tissue registration can be reduced to the problem of accurately identifying feature points, such as the center of nuclei.

  2. Phase contrast enhanced high resolution X-ray imaging and tomography of soft tissue

    Science.gov (United States)

    Jakubek, Jan; Granja, Carlos; Dammer, Jiri; Hanus, Robert; Holy, Tomas; Pospisil, Stanislav; Tykva, Richard; Uher, Josef; Vykydal, Zdenek

    2007-02-01

    A tabletop system for digital high resolution and high sensitivity X-ray micro-radiography has been developed for small-animal and soft-tissue imaging. The system is based on a micro-focus X-ray tube and the semiconductor hybrid position sensitive Medipix2 pixel detector. Transmission radiography imaging, conventionally based only on absorption, is enhanced by exploiting phase-shift effects induced in the X-ray beam traversing the sample. Phase contrast imaging is realized by object edge enhancement. DAQ is done by a novel fully integrated USB-based readout with online image generation. Improved signal reconstruction techniques make use of advanced statistical data analysis, enhanced beam hardening correction and direct thickness calibration of individual pixels. 2D and 3D micro-tomography images of several biological samples demonstrate the applicability of the system for biological and medical purposes including in-vivo and time dependent physiological studies in the life sciences.

  3. Automatic Centerline Extraction of Coverd Roads by Surrounding Objects from High Resolution Satellite Images

    Science.gov (United States)

    Kamangir, H.; Momeni, M.; Satari, M.

    2017-09-01

    This paper presents an automatic method to extract road centerline networks from high and very high resolution satellite images. The present paper addresses the automated extraction roads covered with multiple natural and artificial objects such as trees, vehicles and either shadows of buildings or trees. In order to have a precise road extraction, this method implements three stages including: classification of images based on maximum likelihood algorithm to categorize images into interested classes, modification process on classified images by connected component and morphological operators to extract pixels of desired objects by removing undesirable pixels of each class, and finally line extraction based on RANSAC algorithm. In order to evaluate performance of the proposed method, the generated results are compared with ground truth road map as a reference. The evaluation performance of the proposed method using representative test images show completeness values ranging between 77% and 93%.

  4. A low-cost, high-resolution, video-rate imaging optical radar

    Energy Technology Data Exchange (ETDEWEB)

    Sackos, J.T.; Nellums, R.O.; Lebien, S.M.; Diegert, C.F. [Sandia National Labs., Albuquerque, NM (United States); Grantham, J.W.; Monson, T. [Air Force Research Lab., Eglin AFB, FL (United States)

    1998-04-01

    Sandia National Laboratories has developed a unique type of portable low-cost range imaging optical radar (laser radar or LADAR). This innovative sensor is comprised of an active floodlight scene illuminator and an image intensified CCD camera receiver. It is a solid-state device (no moving parts) that offers significant size, performance, reliability, and simplicity advantages over other types of 3-D imaging sensors. This unique flash LADAR is based on low cost, commercially available hardware, and is well suited for many government and commercial uses. This paper presents an update of Sandia`s development of the Scannerless Range Imager technology and applications, and discusses the progress that has been made in evolving the sensor into a compact, low, cost, high-resolution, video rate Laser Dynamic Range Imager.

  5. A Multi-view Dense Matching Algorithm of High Resolution Aerial Images Based on Graph Network

    Directory of Open Access Journals (Sweden)

    YAN Li

    2016-10-01

    Full Text Available A multi-view dense matching algorithm of high resolution aerial images based on graph network was presented. Overlap ratio and direction between adjacent images was used to find the candidate stereo pairs and build the graph network, then a Coarse-to-Fine strategy based on modified semi-global matching algorithm (SGM was adapted to calculate the disparity map of stereo pairs. Finally, dense point cloud was generated and fused using a multi-triangulation method based on graph network. In the experiment part, the Vaihingen aerial image dataset and the oblique nadir image block of Zürich in ISPRS/EuroSDR project were used to test the algorithm above. Experiment results show that out method is effective for multi-view dense matching of high resolution aerial images in consideration of completeness, efficiency and precision, while the RMS of average reprojection error can reach subpixel level and the actual deviation is better than 1.5 GSD. Due to the introduction of guided median filter, regions of sharp discontinuities, weak textureness or repeat textureness like buildings, vegetation and water body can also be matched well.

  6. Hierarchical graph-based segmentation for extracting road networks from high-resolution satellite images

    Science.gov (United States)

    Alshehhi, Rasha; Marpu, Prashanth Reddy

    2017-04-01

    Extraction of road networks in urban areas from remotely sensed imagery plays an important role in many urban applications (e.g. road navigation, geometric correction of urban remote sensing images, updating geographic information systems, etc.). It is normally difficult to accurately differentiate road from its background due to the complex geometry of the buildings and the acquisition geometry of the sensor. In this paper, we present a new method for extracting roads from high-resolution imagery based on hierarchical graph-based image segmentation. The proposed method consists of: 1. Extracting features (e.g., using Gabor and morphological filtering) to enhance the contrast between road and non-road pixels, 2. Graph-based segmentation consisting of (i) Constructing a graph representation of the image based on initial segmentation and (ii) Hierarchical merging and splitting of image segments based on color and shape features, and 3. Post-processing to remove irregularities in the extracted road segments. Experiments are conducted on three challenging datasets of high-resolution images to demonstrate the proposed method and compare with other similar approaches. The results demonstrate the validity and superior performance of the proposed method for road extraction in urban areas.

  7. High-resolution x-ray imaging using a structured scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Hormozan, Yashar, E-mail: hormozan@kth.se; Sychugov, Ilya; Linnros, Jan [Materials and Nano Physics, School of Information and Communication Technology, KTH Royal Institute of Technology, Electrum 229, Kista, Stockholm SE-16440 (Sweden)

    2016-02-15

    Purpose: In this study, the authors introduce a new generation of finely structured scintillators with a very high spatial resolution (a few micrometers) compared to conventional scintillators, yet maintaining a thick absorbing layer for improved detectivity. Methods: Their concept is based on a 2D array of high aspect ratio pores which are fabricated by ICP etching, with spacings (pitches) of a few micrometers, on silicon and oxidation of the pore walls. The pores were subsequently filled by melting of powdered CsI(Tl), as the scintillating agent. In order to couple the secondary emitted photons of the back of the scintillator array to a CCD device, having a larger pixel size than the pore pitch, an open optical microscope with adjustable magnification was designed and implemented. By imaging a sharp edge, the authors were able to calculate the modulation transfer function (MTF) of this finely structured scintillator. Results: The x-ray images of individually resolved pores suggest that they have been almost uniformly filled, and the MTF measurements show the feasibility of a few microns spatial resolution imaging, as set by the scintillator pore size. Compared to existing techniques utilizing CsI needles as a structured scintillator, their results imply an almost sevenfold improvement in resolution. Finally, high resolution images, taken by their detector, are presented. Conclusions: The presented work successfully shows the functionality of their detector concept for high resolution imaging and further fabrication developments are most likely to result in higher quantum efficiencies.

  8. Fusion of shallow and deep features for classification of high-resolution remote sensing images

    Science.gov (United States)

    Gao, Lang; Tian, Tian; Sun, Xiao; Li, Hang

    2018-02-01

    Effective spectral and spatial pixel description plays a significant role for the classification of high resolution remote sensing images. Current approaches of pixel-based feature extraction are of two main kinds: one includes the widelyused principal component analysis (PCA) and gray level co-occurrence matrix (GLCM) as the representative of the shallow spectral and shape features, and the other refers to the deep learning-based methods which employ deep neural networks and have made great promotion on classification accuracy. However, the former traditional features are insufficient to depict complex distribution of high resolution images, while the deep features demand plenty of samples to train the network otherwise over fitting easily occurs if only limited samples are involved in the training. In view of the above, we propose a GLCM-based convolution neural network (CNN) approach to extract features and implement classification for high resolution remote sensing images. The employment of GLCM is able to represent the original images and eliminate redundant information and undesired noises. Meanwhile, taking shallow features as the input of deep network will contribute to a better guidance and interpretability. In consideration of the amount of samples, some strategies such as L2 regularization and dropout methods are used to prevent over-fitting. The fine-tuning strategy is also used in our study to reduce training time and further enhance the generalization performance of the network. Experiments with popular data sets such as PaviaU data validate that our proposed method leads to a performance improvement compared to individual involved approaches.

  9. High-resolution onshore seismic imaging of complex volcanic structures: An example from Vulcano Island, Italy

    Science.gov (United States)

    Bruno, Pier Paolo G.; Castiello, Antonio

    2009-12-01

    Detailed seismic images of subsurface structures of volcanic calderas are fundamental to improve the structural and volcanological knowledge of these high-risk volcanoes. However, high-quality seismic data are difficult to obtain in volcanic areas, especially on shore. We report the results of a high-resolution seismic profiling of the western sector of La Fossa Caldera (Vulcano Island, Italy). Using a high-resolution vibrating source and both alternative acquisition and processing techniques, we were able to overcome most of the inconvenience caused by volcanic lithotypes. This study provides the subsurface distribution of volcanic deposits as well as the recognition of some significant intracaldera structures. We located a parasitic vent or hyaloclastite mound buried under La Fossa Caldera, which is dissipating CO2 in an area where earthquakes have been recorded at about 1 km depth. Furthermore, the deformation pattern found at the southernmost part of the profile is consistent with a caldera collapse after a dome intrusion. The results suggest that the use of high-resolution vibrating sources combined with alternative seismic acquisition techniques and nonconventional processing could help to recover detailed information on the shallow structures of volcanic areas.

  10. A flexible and accurate digital volume correlation method applicable to high-resolution volumetric images

    Science.gov (United States)

    Pan, Bing; Wang, Bo

    2017-10-01

    Digital volume correlation (DVC) is a powerful technique for quantifying interior deformation within solid opaque materials and biological tissues. In the last two decades, great efforts have been made to improve the accuracy and efficiency of the DVC algorithm. However, there is still a lack of a flexible, robust and accurate version that can be efficiently implemented in personal computers with limited RAM. This paper proposes an advanced DVC method that can realize accurate full-field internal deformation measurement applicable to high-resolution volume images with up to billions of voxels. Specifically, a novel layer-wise reliability-guided displacement tracking strategy combined with dynamic data management is presented to guide the DVC computation from slice to slice. The displacements at specified calculation points in each layer are computed using the advanced 3D inverse-compositional Gauss-Newton algorithm with the complete initial guess of the deformation vector accurately predicted from the computed calculation points. Since only limited slices of interest in the reference and deformed volume images rather than the whole volume images are required, the DVC calculation can thus be efficiently implemented on personal computers. The flexibility, accuracy and efficiency of the presented DVC approach are demonstrated by analyzing computer-simulated and experimentally obtained high-resolution volume images.

  11. SPMK AND GRABCUT BASED TARGET EXTRACTION FROM HIGH RESOLUTION REMOTE SENSING IMAGES

    Directory of Open Access Journals (Sweden)

    W. Cui

    2016-06-01

    Full Text Available Target detection and extraction from high resolution remote sensing images is a basic and wide needed application. In this paper, to improve the efficiency of image interpretation, we propose a detection and segmentation combined method to realize semi-automatic target extraction. We introduce the dense transform color scale invariant feature transform (TC-SIFT descriptor and the histogram of oriented gradients (HOG & HSV descriptor to characterize the spatial structure and color information of the targets. With the k-means cluster method, we get the bag of visual words, and then, we adopt three levels’ spatial pyramid (SP to represent the target patch. After gathering lots of different kinds of target image patches from many high resolution UAV images, and using the TC-SIFT-SP and the multi-scale HOG & HSV feature, we constructed the SVM classifier to detect the target. In this paper, we take buildings as the targets. Experiment results show that the target detection accuracy of buildings can reach to above 90%. Based on the detection results which are a series of rectangle regions of the targets. We select the rectangle regions as candidates for foreground and adopt the GrabCut based and boundary regularized semi-auto interactive segmentation algorithm to get the accurate boundary of the target. Experiment results show its accuracy and efficiency. It can be an effective way for some special targets extraction.

  12. Spmk and Grabcut Based Target Extraction from High Resolution Remote Sensing Images

    Science.gov (United States)

    Cui, Weihong; Wang, Guofeng; Feng, Chenyi; Zheng, Yiwei; Li, Jonathan; Zhang, Yi

    2016-06-01

    Target detection and extraction from high resolution remote sensing images is a basic and wide needed application. In this paper, to improve the efficiency of image interpretation, we propose a detection and segmentation combined method to realize semi-automatic target extraction. We introduce the dense transform color scale invariant feature transform (TC-SIFT) descriptor and the histogram of oriented gradients (HOG) & HSV descriptor to characterize the spatial structure and color information of the targets. With the k-means cluster method, we get the bag of visual words, and then, we adopt three levels' spatial pyramid (SP) to represent the target patch. After gathering lots of different kinds of target image patches from many high resolution UAV images, and using the TC-SIFT-SP and the multi-scale HOG & HSV feature, we constructed the SVM classifier to detect the target. In this paper, we take buildings as the targets. Experiment results show that the target detection accuracy of buildings can reach to above 90%. Based on the detection results which are a series of rectangle regions of the targets. We select the rectangle regions as candidates for foreground and adopt the GrabCut based and boundary regularized semi-auto interactive segmentation algorithm to get the accurate boundary of the target. Experiment results show its accuracy and efficiency. It can be an effective way for some special targets extraction.

  13. Time-optimized high-resolution readout-segmented diffusion tensor imaging.

    Directory of Open Access Journals (Sweden)

    Gernot Reishofer

    Full Text Available Readout-segmented echo planar imaging with 2D navigator-based reacquisition is an uprising technique enabling the sampling of high-resolution diffusion images with reduced susceptibility artifacts. However, low signal from the small voxels and long scan times hamper the clinical applicability. Therefore, we introduce a regularization algorithm based on total variation that is applied directly on the entire diffusion tensor. The spatially varying regularization parameter is determined automatically dependent on spatial variations in signal-to-noise ratio thus, avoiding over- or under-regularization. Information about the noise distribution in the diffusion tensor is extracted from the diffusion weighted images by means of complex independent component analysis. Moreover, the combination of those features enables processing of the diffusion data absolutely user independent. Tractography from in vivo data and from a software phantom demonstrate the advantage of the spatially varying regularization compared to un-regularized data with respect to parameters relevant for fiber-tracking such as Mean Fiber Length, Track Count, Volume and Voxel Count. Specifically, for in vivo data findings suggest that tractography results from the regularized diffusion tensor based on one measurement (16 min generates results comparable to the un-regularized data with three averages (48 min. This significant reduction in scan time renders high resolution (1 × 1 × 2.5 mm(3 diffusion tensor imaging of the entire brain applicable in a clinical context.

  14. In-vivo high resolution corneal imaging and analysis on animal models for clinical applications

    Science.gov (United States)

    Hong, Jesmond; Shinoj, V. K.; Murukeshan, V. M.; Baskaran, M.; Aung, Tin

    2015-07-01

    A simple and low cost optical probe system for the high resolution imaging of the cornea is proposed, based on a Gaussian beam epi-illumination configuration. Corneal topography is obtained by moving the scanning spot across the eye in a raster fashion whereas pachymetry data is achieved by reconstructing the images obtained at different depths. The proposed prototype has been successfully tested on porcine eye samples ex vivo and subsequently on laboratory animals, such as the New Zealand White Rabbit, in vivo. This proposed system and methodology pave the way for realizing a simple and inexpensive optical configuration for pachymetry and keratometry readings, with achievable resolution up to the cellular level. This novel and non-contact high resolution imaging modality demonstrates high intraobserver reproducibility and repeatability. Together with its sophisticated data analysis strategies and safety profile, it is believed to complement existing imaging modalities in the assessment and evaluation of corneal diseases, which enable a decrease in morbidity and improvement in the effectiveness of subsequent treatment.

  15. MTRC compensation in high-resolution ISAR imaging via improved polar format algorithm

    Science.gov (United States)

    Liu, Yang; Li, Hao; Li, Na; Xu, Shiyou; Chen, Zengping

    2014-10-01

    Migration through resolution cells (MTRC) is generated in high-resolution inverse synthetic aperture radar (ISAR) imaging. A MTRC compensation algorithm for high-resolution ISAR imaging based on improved polar format algorithm (PFA) is proposed in this paper. Firstly, in the situation that a rigid-body target stably flies, the initial value of the rotation angle and center of the target is obtained from the rotation of radar line of sight (RLOS) and high range resolution profile (HRRP). Then, the PFA is iteratively applied to the echo data to search the optimization solution based on minimum entropy criterion. The procedure starts with the estimated initial rotation angle and center, and terminated when the entropy of the compensated ISAR image is minimized. To reduce the computational load, the 2-D iterative search is divided into two 1-D search. One is carried along the rotation angle and the other one is carried along rotation center. Each of the 1-D searches is realized by using of the golden section search method. The accurate rotation angle and center can be obtained when the iterative search terminates. Finally, apply the PFA to compensate the MTRC by the use of the obtained optimized rotation angle and center. After MTRC compensation, the ISAR image can be best focused. Simulated and real data demonstrate the effectiveness and robustness of the proposed algorithm.

  16. High-Resolution Imaging System (HiRIS) based on H9500 PSPMT

    International Nuclear Information System (INIS)

    Trotta, C.; Massari, R.; Trinci, G.; Palermo, N.; Boccalini, S.; Scopinaro, F.; Soluri, A.

    2008-01-01

    The H8500 PhotoMultiplier Tube (PMT) from Hamamatsu has been used in the last years to assemble several scintigraphic devices in order to achieve high-resolution gamma cameras. If the detector is coupled to discrete scintillator with millimetric pixel size, the resulting charge distribution that emerges is not properly sampled by its anodes (6x6 mm 2 ). The new position sensitive PMT H9500, with its 3x3 mm 2 anodes, allows a better charge distribution sampling, improving both spatial resolution and linearity of the system. In this paper, we investigate the imaging performances of the H9500 PMT coupled with a CsI(Tl) array having 1 mm pixel size and compare the results with the same scintillator coupled with H8500 PMT. A portable imaging system named HiRIS (High-Resolution Imaging System) was then realized using a miniaturized readout electronic. Thanks to its lightness, it can be easily used in Medical Imaging. We used HiRIS, together with a rotating system, to carry out a tomographic reconstruction of the biodistribution of a radiopharmaceutical in rats

  17. High-resolution ultrasound imaging and noninvasive optoacoustic monitoring of blood variables in peripheral blood vessels

    Science.gov (United States)

    Petrov, Irene Y.; Petrov, Yuriy; Prough, Donald S.; Esenaliev, Rinat O.

    2011-03-01

    Ultrasound imaging is being widely used in clinics to obtain diagnostic information non-invasively and in real time. A high-resolution ultrasound imaging platform, Vevo (VisualSonics, Inc.) provides in vivo, real-time images with exceptional resolution (up to 30 microns) using high-frequency transducers (up to 80 MHz). Recently, we built optoacoustic systems for probing radial artery and peripheral veins that can be used for noninvasive monitoring of total hemoglobin concentration, oxyhemoglobin saturation, and concentration of important endogenous and exogenous chromophores (such as ICG). In this work we used the high-resolution ultrasound imaging system Vevo 770 for visualization of the radial artery and peripheral veins and acquired corresponding optoacoustic signals from them using the optoacoustic systems. Analysis of the optoacoustic data with a specially developed algorithm allowed for measurement of blood oxygenation in the blood vessels as well as for continuous, real-time monitoring of arterial and venous blood oxygenation. Our results indicate that: 1) the optoacoustic technique (unlike pure optical approaches and other noninvasive techniques) is capable of accurate peripheral venous oxygenation measurement; and 2) peripheral venous oxygenation is dependent on skin temperature and local hemodynamics. Moreover, we performed for the first time (to the best of our knowledge) a comparative study of optoacoustic arterial oximetry and a standard pulse oximeter in humans and demonstrated superior performance of the optoacoustic arterial oximeter, in particular at low blood flow.

  18. STUDY ON HIGH RESOLUTION MEMBRANE-BASED DIFFRACTIVE OPTICAL IMAGING ON GEOSTATIONARY ORBIT

    Directory of Open Access Journals (Sweden)

    J. Jiao

    2017-05-01

    Full Text Available Diffractive optical imaging technology provides a new way to realize high resolution earth observation on geostationary orbit. There are a lot of benefits to use the membrane-based diffractive optical element in ultra-large aperture optical imaging system, including loose tolerance, light weight, easy folding and unfolding, which make it easy to realize high resolution earth observation on geostationary orbit. The implementation of this technology also faces some challenges, including the configuration of the diffractive primary lens, the development of high diffraction efficiency membrane-based diffractive optical elements, and the correction of the chromatic aberration of the diffractive optical elements. Aiming at the configuration of the diffractive primary lens, the “6+1” petal-type unfold scheme is proposed, which consider the compression ratio, the blocking rate and the development complexity. For high diffraction efficiency membrane-based diffractive optical element, a self-collimating method is proposed. The diffraction efficiency is more than 90 % of the theoretical value. For the chromatic aberration correction problem, an optimization method based on schupmann is proposed to make the imaging spectral bandwidth in visible light band reach 100 nm. The above conclusions have reference significance for the development of ultra-large aperture diffractive optical imaging system.

  19. Automatic Detection of Changes on Mars Surface from High-Resolution Orbital Images

    Science.gov (United States)

    Sidiropoulos, Panagiotis; Muller, Jan-Peter

    2017-04-01

    Over the last 40 years Mars has been extensively mapped by several NASA and ESA orbital missions, generating a large image dataset comprised of approximately 500,000 high-resolution images (of human resources, which is very difficult to achieve when dealing with a rapidly increasing volume of data. Although citizen science can be employed for training and verification it is unsuitable for planetwide systematic change detection. In this work, we introduce a novel approach in planetary image change detection, which involves a batch-mode automatic change detection pipeline that identifies regions that have changed. This is tested in anger, on tens of thousands of high-resolution images over the MC11 quadrangle [5], acquired by CTX, HRSC, THEMIS-VIS and MOC-NA instruments [1]. We will present results which indicate a substantial level of activity in this region of Mars, including instances of dynamic natural phenomena that haven't been cataloged in the planetary science literature before. We will demonstrate the potential and usefulness of such an automatic approach in planetary science change detection. Acknowledgments: The research leading to these results has received funding from the STFC "MSSL Consolidated Grant" ST/K000977/1 and partial support from the European Union's Seventh Framework Programme (FP7/2007-2013) under iMars grant agreement n° 607379. References: [1] P. Sidiropoulos and J. - P. Muller (2015) On the status of orbital high-resolution repeat imaging of Mars for the observation of dynamic surface processes. Planetary and Space Science, 117: 207-222. [2] O. Aharonson, et al. (2003) Slope streak formation and dust deposition rates on Mars. Journal of Geophysical Research: Planets, 108(E12):5138 [3] A. McEwen, et al. (2011) Seasonal flows on warm martian slopes. Science, 333 (6043): 740-743. [4] S. Byrne, et al. (2009) Distribution of mid-latitude ground ice on mars from new impact craters. Science, 325(5948):1674-1676. [5] K. Gwinner, et al (2016) The

  20. High resolution satellite image indexing and retrieval using SURF features and bag of visual words

    Science.gov (United States)

    Bouteldja, Samia; Kourgli, Assia

    2017-03-01

    In this paper, we evaluate the performance of SURF descriptor for high resolution satellite imagery (HRSI) retrieval through a BoVW model on a land-use/land-cover (LULC) dataset. Local feature approaches such as SIFT and SURF descriptors can deal with a large variation of scale, rotation and illumination of the images, providing, therefore, a better discriminative power and retrieval efficiency than global features, especially for HRSI which contain a great range of objects and spatial patterns. Moreover, we combine SURF and color features to improve the retrieval accuracy, and we propose to learn a category-specific dictionary for each image category which results in a more discriminative image representation and boosts the image retrieval performance.

  1. High resolution photoacoustic imaging of microvasculature in normal and cancerous bladders

    Science.gov (United States)

    Xie, Zhixing; Roberts, William; Carson, Paul L.; Liu, Xiaojun; Tao, Chao; Wang, Xueding

    2013-03-01

    We explored the potential of an emerging laser-based technology, photoacoustic imaging (PAI), for bladder cancer diagnosis through high resolution imaging of microvasculature in the interior bladder tissues. Images of ex vivo canine bladders demonstrated the excellent ability of PAI to map three-dimensional microvasculature in optically scattering bladder tissues. By comparing the results from human bladder specimens affected by cancer to those from the normal control, the feasibility of PAI in differentiating malignant from benign bladder tissues was explored. The reported distinctive morphometric characteristics of tumor microvasculature can be seen in the images from cancer samples, suggesting that PAI may allow in vivo assessment of neoangiogenesis that is closely associated with bladder cancer generation and progression. By presenting subsurface morphological and physiological information in bladder tissues, PAI, when performed in a similar way to that in conventional endoscopy, provides an opportunity for improved diagnosis, staging and treatment guidance of bladder cancer.

  2. High-resolution real-time sonography and MR imaging in assessment of osteocartilaginous exostoses

    International Nuclear Information System (INIS)

    Prayer, L.M.; Kropej, D.H.; Wimberger, D.M.; Wurnig, C.F.; Kramer, J.; Kainberger, F.M.; Braun, O.H.; Ritschl, P.W.; Imhof, H.

    1991-01-01

    High-resolution real-time ultrasonography (US) and MR imaging, using both spin-echo (SE) and gradient-echo (GE) sequences, were performed prospectively in 14 patients with solitary osteocartilaginous exostoses to assess cartilage cap thickness and bursa formation. Results were compared to surgical and histopathologic findings in all cases. Both US and MR imaging were useful in evaluating exostotic cartilage cap thickness, which is supposed to be the most reliable sign of malignant transformation. Hyaline cartilage matrix had distinctive features in US and MR imaging caused by its specific histologic composition. The formation of bursae over the protruding exostoses, which results in pain and clinically could raise the suspicion of growth and malignant transformation, was demonstrated best using GE sequences. MR imaging was thus superior to US in the detection of bursa formation. (orig.)

  3. Signal processing of high-resolution transmission electron microscope images using Fourier transforms

    Energy Technology Data Exchange (ETDEWEB)

    Buseck, P.R.; Epelboin, Y.; Rimsky, A.

    1988-11-01

    Interpretation of images obtained by high-resolution transmission electron microscopy (HRTEM) can be aided by the use of processed signals. Images are recorded digitally or are digitized from a photograph, and then these data are Fourier transformed and treated. The low- and high-frequency signals are removed, and a variety of circular and elliptical (anisotropic) apertures or screens are applied to explore and highlight features of special interest. A minicomputer can be used to perform such image processing rapidly, interactively, and with high precision. Elliptical filters are of special interest for the examination of linear or planar features such as the distribution of stacking faults or the presence and distribution of superstructures. Some superstructures themselves contain defects, and these can similarly be highlighted and examined. The uses of processing for examining HRTEM images of layering in a complex sheet silicate mineral and dislocation cores in grossular garnet are illustrated.

  4. Illumination invariant feature point matching for high-resolution planetary remote sensing images

    Science.gov (United States)

    Wu, Bo; Zeng, Hai; Hu, Han

    2018-03-01

    Despite its success with regular close-range and remote-sensing images, the scale-invariant feature transform (SIFT) algorithm is essentially not invariant to illumination differences due to the use of gradients for feature description. In planetary remote sensing imagery, which normally lacks sufficient textural information, salient regions are generally triggered by the shadow effects of keypoints, reducing the matching performance of classical SIFT. Based on the observation of dual peaks in a histogram of the dominant orientations of SIFT keypoints, this paper proposes an illumination-invariant SIFT matching method for high-resolution planetary remote sensing images. First, as the peaks in the orientation histogram are generally aligned closely with the sub-solar azimuth angle at the time of image collection, an adaptive suppression Gaussian function is tuned to level the histogram and thereby alleviate the differences in illumination caused by a changing solar angle. Next, the suppression function is incorporated into the original SIFT procedure for obtaining feature descriptors, which are used for initial image matching. Finally, as the distribution of feature descriptors changes after anisotropic suppression, and the ratio check used for matching and outlier removal in classical SIFT may produce inferior results, this paper proposes an improved matching procedure based on cross-checking and template image matching. The experimental results for several high-resolution remote sensing images from both the Moon and Mars, with illumination differences of 20°-180°, reveal that the proposed method retrieves about 40%-60% more matches than the classical SIFT method. The proposed method is of significance for matching or co-registration of planetary remote sensing images for their synergistic use in various applications. It also has the potential to be useful for flyby and rover images by integrating with the affine invariant feature detectors.

  5. High-Resolution MR Imaging of the Human Brainstem In vivo at 7 Tesla

    Science.gov (United States)

    Deistung, Andreas; Schäfer, Andreas; Schweser, Ferdinand; Biedermann, Uta; Güllmar, Daniel; Trampel, Robert; Turner, Robert; Reichenbach, Jürgen R.

    2013-01-01

    The human brainstem, which comprises a multitude of axonal nerve fibers and nuclei, plays an important functional role in the human brain. Depicting its anatomy non-invasively with high spatial resolution may thus in turn help to better relate normal and pathological anatomical variations to medical conditions as well as neurological and peripheral functions. We explored the potential of high-resolution magnetic resonance imaging (MRI) at 7 T for depicting the intricate anatomy of the human brainstem in vivo by acquiring and generating images with multiple contrasts: T2-weighted images, quantitative maps of longitudinal relaxation rate (R1 maps) and effective transverse relaxation rate (R2* maps), magnetic susceptibility maps, and direction-encoded track-density images. Images and quantitative maps were compared with histological stains and anatomical atlases to identify nerve nuclei and nerve fibers. Among the investigated contrasts, susceptibility maps displayed the largest number of brainstem structures. Contrary to R1 maps and T2-weighted images, which showed rather homogeneous contrast, R2* maps, magnetic susceptibility maps, and track-density images clearly displayed a multitude of smaller and larger fiber bundles. Several brainstem nuclei were identifiable in sections covering the pons and medulla oblongata, including the spinal trigeminal nucleus and the reticulotegmental nucleus on magnetic susceptibility maps as well as the inferior olive on R1, R2*, and susceptibility maps. The substantia nigra and red nuclei were visible in all contrasts. In conclusion, high-resolution, multi-contrast MR imaging at 7 T is a versatile tool to non-invasively assess the individual anatomy and tissue composition of the human brainstem. PMID:24194710

  6. High-resolution three-dimensional imaging and analysis of rock falls in Yosemite valley, California

    Science.gov (United States)

    Stock, Gregory M.; Bawden, G.W.; Green, J.K.; Hanson, E.; Downing, G.; Collins, B.D.; Bond, S.; Leslar, M.

    2011-01-01

    We present quantitative analyses of recent large rock falls in Yosemite Valley, California, using integrated high-resolution imaging techniques. Rock falls commonly occur from the glacially sculpted granitic walls of Yosemite Valley, modifying this iconic landscape but also posing signifi cant potential hazards and risks. Two large rock falls occurred from the cliff beneath Glacier Point in eastern Yosemite Valley on 7 and 8 October 2008, causing minor injuries and damaging structures in a developed area. We used a combination of gigapixel photography, airborne laser scanning (ALS) data, and ground-based terrestrial laser scanning (TLS) data to characterize the rock-fall detachment surface and adjacent cliff area, quantify the rock-fall volume, evaluate the geologic structure that contributed to failure, and assess the likely failure mode. We merged the ALS and TLS data to resolve the complex, vertical to overhanging topography of the Glacier Point area in three dimensions, and integrated these data with gigapixel photographs to fully image the cliff face in high resolution. Three-dimensional analysis of repeat TLS data reveals that the cumulative failure consisted of a near-planar rock slab with a maximum length of 69.0 m, a mean thickness of 2.1 m, a detachment surface area of 2750 m2, and a volume of 5663 ?? 36 m3. Failure occurred along a surfaceparallel, vertically oriented sheeting joint in a clear example of granitic exfoliation. Stress concentration at crack tips likely propagated fractures through the partially attached slab, leading to failure. Our results demonstrate the utility of high-resolution imaging techniques for quantifying far-range (>1 km) rock falls occurring from the largely inaccessible, vertical rock faces of Yosemite Valley, and for providing highly accurate and precise data needed for rock-fall hazard assessment. ?? 2011 Geological Society of America.

  7. Ultrafast, high resolution, phase contrast imaging of impact response with synchrotron radiation

    Directory of Open Access Journals (Sweden)

    B. J. Jensen

    2012-03-01

    Full Text Available Understanding the dynamic response of materials at extreme conditions requires diagnostics that can provide real-time, in situ, spatially resolved measurements on the nanosecond timescale. The development of methods such as phase contrast imaging (PCI typically used at synchrotron sources offer unique opportunities to examine dynamic material response. In this work, we report ultrafast, high-resolution, dynamic PCI measurements of shock compressed materials with 3 μm spatial resolution using a single 60 ps synchrotron X-ray bunch. These results firmly establish the use of PCI to examine dynamic phenomena at ns to μs timescales.

  8. High-resolution imaging and target designation through clouds or smoke

    Science.gov (United States)

    Perry, Michael D.

    2003-01-01

    A method and system of combining gated intensifiers and advances in solid-state, short-pulse laser technology, compact systems capable of producing high resolution (i.e., approximately less than 20 centimeters) optical images through a scattering medium such as dense clouds, fog, smoke, etc. may be achieved from air or ground based platforms. Laser target designation through a scattering medium is also enabled by utilizing a short pulse illumination laser and a relatively minor change to the detectors on laser guided munitions.

  9. Michelson Interferometer for Global High-Resolution Thermospheric Imaging (MIGHTI): Monolithic Interferometer Design and Test

    Science.gov (United States)

    Harlander, John M.; Englert, Christoph R.; Brown, Charles M.; Marr, Kenneth D.; Miller, Ian J.; Zastera, Vaz; Bach, Bernhard W.; Mende, Stephen B.

    2017-10-01

    The design and laboratory tests of the interferometers for the Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument which measures thermospheric wind and temperature for the NASA-sponsored Ionospheric Connection (ICON) Explorer mission are described. The monolithic interferometers use the Doppler Asymmetric Spatial Heterodyne (DASH) Spectroscopy technique for wind measurements and a multi-element photometer approach to measure thermospheric temperatures. The DASH technique and overall optical design of the MIGHTI instrument are described in an overview followed by details on the design, element fabrication, assembly, laboratory tests and thermal control of the interferometers that are the heart of MIGHTI.

  10. CNES studies for on-board compression of high-resolution satellite images

    Science.gov (United States)

    Thiebaut, Carole; Delaunay, Xavier; Latry, Christophe; Moury, Gilles

    2008-08-01

    Future high resolution instruments planned by CNES for space remote sensing missions will lead to higher bit rates because of the increase in resolution and dynamic range. For example, the ground resolution improvement induces a data rate multi-plied by 8 from SPOT4 to SPOT5 and by 28 to PLEIADES-HR. Lossy data compression with low complexity algorithms is then needed since compression ratio are always higher. New image compression algorithms have been used to increase their compression performance while complying with image quality requirements from the community of users and experts. Thus, DPCM algorithm used on-board SPOT4 was replaced by a DCT-based compressor on-board SPOT5. Recent compression algorithms such as PLEIADES-HR one use a wavelet-transform and a bit-plane encoder. But future compressors will have to be more powerful to reach higher compression ratios. New transforms are studied by CNES to exceed the DWT but a per-formance gap could be obtained with selective compression. This article gives an overview of CNES past and present studies of on-board compression algorithms for high-resolution images.

  11. On chip cryo-anesthesia of Drosophila larvae for high resolution in vivo imaging applications.

    Science.gov (United States)

    Chaudhury, Amrita Ray; Insolera, Ryan; Hwang, Ran-Der; Fridell, Yih-Woei; Collins, Catherine; Chronis, Nikos

    2017-06-27

    We present a microfluidic chip for immobilizing Drosophila melanogaster larvae for high resolution in vivo imaging. The chip creates a low-temperature micro-environment that anaesthetizes and immobilizes the larva in under 3 minutes. We characterized the temperature distribution within the chip and analyzed the resulting larval body movement using high resolution fluorescence imaging. Our results indicate that the proposed method minimizes submicron movements of internal organs and tissue without affecting the larva physiology. It can be used to continuously immobilize larvae for short periods of time (minutes) or for longer periods (several hours) if used intermittently. The same chip can be used to accommodate and immobilize arvae across all developmental stages (1st instar to late 3rd instar), and loading larvae onto the chip does not require any specialized skills. To demonstrate the usability of the chip, we observed mitochondrial trafficking in neurons from the cell bodies to the axon terminals along with mitochondrial fusion and neuro-synaptic growth through time in intact larvae. Besides studying sub-cellular processes and cellular development, we envision the use of on chip cryo-anesthesia in a wide variety of biological in vivo imaging applications, including observing organ development of the salivary glands, fat bodies and body-wall muscles.

  12. AM Multipurpose High-Resolution Imaging Topological Radar (ITR): reverse engineering and artworks monitoring and restoration

    Science.gov (United States)

    Guarneri, Massimiliano; Bartolini, Luciano; Fornetti, Giorgio; Ferri De Collibus, Mario; De Dominicis, Luigi; Paglia, Emiliano; Poggi, Claudio; Ricci, Roberto

    2005-08-01

    A high resolution Amplitude Modulated Imaging Laser Radar (AM-LR) sensor has recently been developed, aimed to accurately reconstructing 3D digital models of real targets - either single objects or large amplitude complex scenes. The system sounding beam can be swept linearly across the object or circularly around it, by placing the object on a controlled rotating platform. Both intensity and phase shift of the back-scattered light are then collected and processed, providing respectively a shade-free photographic-like picture and accurate range data in the form of a range or depth image, with accuracy depending mainly on the laser modulation frequency. The development of software, suitable for simultaneous 3D rendering of the intensity and absolute distance data collected by the ITR, constitutes one of the main objectives of the research activity, whatever is the application pursued. In fact, high resolution AM-LR systems have a great interest for their potentials in accurate 3D imaging of valuable objects which must be preserved in digital archives. Examples range from artwork monitoring, cataloguing and restoration from sparse fragments, to medicine for non-hazardous diagnostics and fast design of bio-compatible prostheses, to microtechnology in the miniaturization of macro-components (plastic prototypes, quality control). Several meaningful results of measurements executed in various important European archaeological sites, in particular Santa Maria Antiqua church situated in Fori Imperiali area in Rome and Costanza (Romania), involving 3D color mapped representation are also presented.

  13. Dynamic high-resolution ultrasound in vivo imaging of hyaluronic acid filler injection.

    Science.gov (United States)

    Kohn, Jocelyne C; Goh, Alice S; Lin, Joseph L; Goldberg, Robert A

    2013-11-01

    High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injected in the face. To observe real-time injection of HA using HRU and describe behavior of the gel injection in various anatomic layers and the effect of massage. Deep (preperiosteal), intermediate (subdermal), and superficial (dermal) injections of HA were performed in the supraclavicular area under ultrasonography visualization on a healthy volunteer. Videos were obtained during injection and static images at several time points, including during injection, immediately after injection, 5 minutes after massage of the treated area, and at 2 weeks after injection. During injection, dermally injected HA stayed within the dermis, increasing its echogenicity; subdermally injected HA formed multiple anechoic pearls; and preperiosteal HA produced a single anechoic bubble with diffuse margins. No vertical transection of the planes was observed during injection or after massage. Two-week postinjection imaging showed persistence of the varying HA morphology in each plane. High-resolution ultrasound allows in vivo study of HA injection behavior. HA adopts different morphology within the tissue depending on the density and compliance of the tissues in the plane of injection. © 2013 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

  14. High resolution reconstruction of PET images using the iterative OSEM algorithm

    International Nuclear Information System (INIS)

    Doll, J.; Bublitz, O.; Werling, A.; Haberkorn, U.; Semmler, W.; Adam, L.E.; Pennsylvania Univ., Philadelphia, PA; Brix, G.

    2004-01-01

    Aim: Improvement of the spatial resolution in positron emission tomography (PET) by incorporation of the image-forming characteristics of the scanner into the process of iterative image reconstruction. Methods: All measurements were performed at the whole-body PET system ECAT EXACT HR + in 3D mode. The acquired 3D sinograms were sorted into 2D sinograms by means of the Fourier rebinning (FORE) algorithm, which allows the usage of 2D algorithms for image reconstruction. The scanner characteristics were described by a spatially variant line-spread function (LSF), which was determined from activated copper-64 line sources. This information was used to model the physical degradation processes in PET measurements during the course of 2D image reconstruction with the iterative OSEM algorithm. To assess the performance of the high-resolution OSEM algorithm, phantom measurements performed at a cylinder phantom, the hotspot Jaszczack phantom, and the 3D Hoffmann brain phantom as well as different patient examinations were analyzed. Results: Scanner characteristics could be described by a Gaussian-shaped LSF with a full-width at half-maximum increasing from 4.8 mm at the center to 5.5 mm at a radial distance of 10.5 cm. Incorporation of the LSF into the iteration formula resulted in a markedly improved resolution of 3.0 and 3.5 mm, respectively. The evaluation of phantom and patient studies showed that the high-resolution OSEM algorithm not only lead to a better contrast resolution in the reconstructed activity distributions but also to an improved accuracy in the quantification of activity concentrations in small structures without leading to an amplification of image noise or even the occurrence of image artifacts. Conclusion: The spatial and contrast resolution of PET scans can markedly be improved by the presented image restauration algorithm, which is of special interest for the examination of both patients with brain disorders and small animals. (orig.)

  15. Statistical dynamic image reconstruction in state-of-the-art high-resolution PET

    International Nuclear Information System (INIS)

    Rahmim, Arman; Cheng, J-C; Blinder, Stephan; Camborde, Maurie-Laure; Sossi, Vesna

    2005-01-01

    Modern high-resolution PET is now more than ever in need of scrutiny into the nature and limitations of the imaging modality itself as well as image reconstruction techniques. In this work, we have reviewed, analysed and addressed the following three considerations within the particular context of state-of-the-art dynamic PET imaging: (i) the typical average numbers of events per line-of-response (LOR) are now (much) less than unity (ii) due to the physical and biological decay of the activity distribution, one requires robust and efficient reconstruction algorithms applicable to a wide range of statistics and (iii) the computational considerations in dynamic imaging are much enhanced (i.e., more frames to be stored and reconstructed). Within the framework of statistical image reconstruction, we have argued theoretically and shown experimentally that the sinogram non-negativity constraint (when using the delayed-coincidence and/or scatter-subtraction techniques) is especially expected to result in an overestimation bias. Subsequently, two schemes are considered: (a) subtraction techniques in which an image non-negativity constraint has been imposed and (b) implementation of random and scatter estimates inside the reconstruction algorithms, thus enabling direct processing of Poisson-distributed prompts. Both techniques are able to remove the aforementioned bias, while the latter, being better conditioned theoretically, is able to exhibit superior noise characteristics. We have also elaborated upon and verified the applicability of the accelerated list-mode image reconstruction method as a powerful solution for accurate, robust and efficient dynamic reconstructions of high-resolution data (as well as a number of additional benefits in the context of state-of-the-art PET)

  16. Ribbon scanning confocal for high-speed high-resolution volume imaging of brain.

    Directory of Open Access Journals (Sweden)

    Alan M Watson

    Full Text Available Whole-brain imaging is becoming a fundamental means of experimental insight; however, achieving subcellular resolution imagery in a reasonable time window has not been possible. We describe the first application of multicolor ribbon scanning confocal methods to collect high-resolution volume images of chemically cleared brains. We demonstrate that ribbon scanning collects images over ten times faster than conventional high speed confocal systems but with equivalent spectral and spatial resolution. Further, using this technology, we reconstruct large volumes of mouse brain infected with encephalitic alphaviruses and demonstrate that regions of the brain with abundant viral replication were inaccessible to vascular perfusion. This reveals that the destruction or collapse of large regions of brain micro vasculature may contribute to the severe disease caused by Venezuelan equine encephalitis virus. Visualization of this fundamental impact of infection would not be possible without sampling at subcellular resolution within large brain volumes.

  17. High-resolution imaging spectrometer (HRIS): optics, focal plane, and calibration

    Science.gov (United States)

    Blechinger, Fritz; Charlton, Dave E.; Davancens, Robert; Harnisch, Bernd; Kunkel, Bernd P.; Meynart, Roland; Novi, Andrea; O'Mongain, Eon; Schwarzer, Horst H.; Slater, Philip N.

    1993-09-01

    HRIS is proposed as a spaceborne, high-resolution imaging spectrometer designed to image a variable (+/- 30 degree(s)) 30 km swath with 40 m SSP pixel size in the spectral range from 450 to 2340 nm with an average 10 nm spectral bandwidth. HRIS is conceived as a push-broom imager with two-dimensional detector arrays for spectral and spatial coverage. The challenging requirements for this instrument will be discussed as well as the concept derived against these requirements. Emphasis is on the optical definition, particularly the spectrometer optics, the focal plane assembly--here mostly the hybrid SWIR CMT detector array--and the calibration concept which includes two external references, ratioing radiometers and an internal reference. The other subunits will be described briefly only. The presentation will conclude with a preliminary development plan.

  18. Ship Detection in High-Resolution Dual-Polarization SAR Amplitude Images

    Directory of Open Access Journals (Sweden)

    Gui Gao

    2013-01-01

    Full Text Available A constant false alarm rate (CFAR detecting method for ships in high-resolution dual-polarization synthetic aperture radar (SAR amplitude images has been proposed in this paper. First, by the production of amplitude images from two polarimetric channels, a novel detector simply called the PMA detector has been constructed. We testified that the PMA detector could improve the signal-to-clutter ratio (SCR and make the discrimination of a ship from clutter more easily. Second, the PMA detector’s statistical model has been described by the well-known distribution when facing complex sea background. The experiments performed on measured dual-polarization TerraSAR-X images demonstrate the good performance of the proposed CFAR detecting method.

  19. High-resolution, air-coupled ultrasonic imaging of thin materials.

    Science.gov (United States)

    Gan, Tat-Hean; Hutchins, David A; Billson, Duncan R; Schindel, David W

    2003-11-01

    This paper describes the use of a focused air-coupled capacitance transducer combined with pulse compression techniques to form high-resolution images of thin materials in air. The focusing of the device is achieved by using an off-axis parabolic mirror. The lateral resolution of the focused transducer, operating over a bandwidth of 1.2 MHz, was found to be less than 0.5 mm. A combination of the focused transducer as a source and a planar receiver in through-transmission mode has been developed for the measurement of different features in paper products, with a lateral resolution in through-transmission imaging of approximately 0.4 mm. Images in air of thin samples such as bank notes, high-quality writing paper, stamps, and sealed joints were obtained without contact to the sample.

  20. STUDY ON BUILDING EXTRACTION FROM HIGH-RESOLUTION IMAGES USING MBI

    Directory of Open Access Journals (Sweden)

    Z. Ding

    2018-04-01

    Full Text Available Building extraction from high resolution remote sensing images is a hot research topic in the field of photogrammetry and remote sensing. However, the diversity and complexity of buildings make building extraction methods still face challenges in terms of accuracy, efficiency, and so on. In this study, a new building extraction framework based on MBI and combined with image segmentation techniques, spectral constraint, shadow constraint, and shape constraint is proposed. In order to verify the proposed method, worldview-2, GF-2, GF-1 remote sensing images covered Xiamen Software Park were used for building extraction experiments. Experimental results indicate that the proposed method improve the original MBI significantly, and the correct rate is over 86 %. Furthermore, the proposed framework reduces the false alarms by 42 % on average compared to the performance of the original MBI.

  1. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere.

    Science.gov (United States)

    Makowska, Małgorzata G; Theil Kuhn, Luise; Cleemann, Lars N; Lauridsen, Erik M; Bilheux, Hassina Z; Molaison, Jamie J; Santodonato, Louis J; Tremsin, Anton S; Grosse, Mirco; Morgano, Manuel; Kabra, Saurabh; Strobl, Markus

    2015-12-01

    High material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. This paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 °C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition, examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. This covers a broad field of research from fundamental to technological investigations of various types of materials and components.

  2. Feasibility and precision of transcutaneous very-high resolution ultrasound for quantification of arterial structures in human neonates - comparison with conventional high resolution vascular ultrasound imaging.

    Science.gov (United States)

    Sundholm, Johnny K M; Olander, Rasmus F W; Ojala, Tiina H; Andersson, Sture; Sarkola, Taisto

    2015-04-01

    Non-invasive transcutaneous very-high resolution ultrasound (VHRU, 25-55 MHz) has recently been developed to quantify superficial vascular structures in humans. The performance of the method has yet not been evaluated in vivo in neonates. The aim of the study was to compare VHRU with conventional high-resolution ultrasound (HRU, 7-12 MHz), and to assess the feasibility and precision of VHRU in this population. 150 images from central elastic (common carotid, CCA) and peripheral muscular (brachial, BA; femoral, FA) arteries were obtained in 25 neonates of different gestational ages (range 33 + 0 to 41 + 5 gestational weeks) and weights (range 1570-4950 g) with VHRU, and the use of HRU for comparison assessed in five. Images were captured from CCAs with 35 MHz, FAs using 35 and 55 MHz, and BAs using 55 MHz. 12 MHz was unable to assess FAs and BAs, and the CCA IMT was grossly overestimated compared with 35-55 MHz. IMTs of the smallest BAs and FAs were beyond the axial resolution of VHRU (assessment of superficial proximal conduit arteries but unable to assess the abdominal aorta in human neonates HRU-derived neonatal conduit arterial wall layer thicknesses are below the ultrasound axial resolution. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  3. An Automated Platform for High-Resolution Tissue Imaging Using Nanospray Desorption Electrospray Ionization Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lanekoff, Ingela T.; Heath, Brandi S.; Liyu, Andrey V.; Thomas, Mathew; Carson, James P.; Laskin, Julia

    2012-10-02

    An automated platform has been developed for acquisition and visualization of mass spectrometry imaging (MSI) data using nanospray desorption electrospray ionization (nano-DESI). The new system enables robust operation of the nano-DESI imaging source over many hours. This is achieved by controlling the distance between the sample and the probe by mounting the sample holder onto an automated XYZ stage and defining the tilt of the sample plane. This approach is useful for imaging of relatively flat samples such as thin tissue sections. Custom software called MSI QuickView was developed for visualization of large data sets generated in imaging experiments. MSI QuickView enables fast visualization of the imaging data during data acquisition and detailed processing after the entire image is acquired. The performance of the system is demonstrated by imaging rat brain tissue sections. High resolution mass analysis combined with MS/MS experiments enabled identification of lipids and metabolites in the tissue section. In addition, high dynamic range and sensitivity of the technique allowed us to generate ion images of low-abundance isobaric lipids. High-spatial resolution image acquired over a small region of the tissue section revealed the spatial distribution of an abundant brain metabolite, creatine, in the white and gray matter that is consistent with the literature data obtained using magnetic resonance spectroscopy.

  4. High resolution depth reconstruction from monocular images and sparse point clouds using deep convolutional neural network

    Science.gov (United States)

    Dimitrievski, Martin; Goossens, Bart; Veelaert, Peter; Philips, Wilfried

    2017-09-01

    Understanding the 3D structure of the environment is advantageous for many tasks in the field of robotics and autonomous vehicles. From the robot's point of view, 3D perception is often formulated as a depth image reconstruction problem. In the literature, dense depth images are often recovered deterministically from stereo image disparities. Other systems use an expensive LiDAR sensor to produce accurate, but semi-sparse depth images. With the advent of deep learning there have also been attempts to estimate depth by only using monocular images. In this paper we combine the best of the two worlds, focusing on a combination of monocular images and low cost LiDAR point clouds. We explore the idea that very sparse depth information accurately captures the global scene structure while variations in image patches can be used to reconstruct local depth to a high resolution. The main contribution of this paper is a supervised learning depth reconstruction system based on a deep convolutional neural network. The network is trained on RGB image patches reinforced with sparse depth information and the output is a depth estimate for each pixel. Using image and point cloud data from the KITTI vision dataset we are able to learn a correspondence between local RGB information and local depth, while at the same time preserving the global scene structure. Our results are evaluated on sequences from the KITTI dataset and our own recordings using a low cost camera and LiDAR setup.

  5. Feasibility of fabricating personalized 3D-printed bone grafts guided by high-resolution imaging

    Science.gov (United States)

    Hong, Abigail L.; Newman, Benjamin T.; Khalid, Arbab; Teter, Olivia M.; Kobe, Elizabeth A.; Shukurova, Malika; Shinde, Rohit; Sipzner, Daniel; Pignolo, Robert J.; Udupa, Jayaram K.; Rajapakse, Chamith S.

    2017-03-01

    Current methods of bone graft treatment for critical size bone defects can give way to several clinical complications such as limited available bone for autografts, non-matching bone structure, lack of strength which can compromise a patient's skeletal system, and sterilization processes that can prevent osteogenesis in the case of allografts. We intend to overcome these disadvantages by generating a patient-specific 3D printed bone graft guided by high-resolution medical imaging. Our synthetic model allows us to customize the graft for the patients' macro- and microstructure and correct any structural deficiencies in the re-meshing process. These 3D-printed models can presumptively serve as the scaffolding for human mesenchymal stem cell (hMSC) engraftment in order to facilitate bone growth. We performed highresolution CT imaging of a cadaveric human proximal femur at 0.030-mm isotropic voxels. We used these images to generate a 3D computer model that mimics bone geometry from micro to macro scale represented by STereoLithography (STL) format. These models were then reformatted to a format that can be interpreted by the 3D printer. To assess how much of the microstructure was replicated, 3D-printed models were re-imaged using micro-CT at 0.025-mm isotropic voxels and compared to original high-resolution CT images used to generate the 3D model in 32 sub-regions. We found a strong correlation between 3D-printed bone volume and volume of bone in the original images used for 3D printing (R2 = 0.97). We expect to further refine our approach with additional testing to create a viable synthetic bone graft with clinical functionality.

  6. High-Resolution 3 T MR Microscopy Imaging of Arterial Walls

    International Nuclear Information System (INIS)

    Sailer, Johannes; Rand, Thomas; Berg, Andreas; Sulzbacher, Irene; Peloschek, P.; Hoelzenbein, Thomas; Lammer, Johannes

    2006-01-01

    Purpose. To achieve a high spatial resolution in MR imaging that allows for clear visualization of anatomy and even histology and documentation of plaque morphology in in vitro samples from patients with advanced atherosclerosis. A further objective of our study was to evaluate whether T2-weighted high-resolution MR imaging can provide accurate classification of atherosclerotic plaque according to a modified American Heart Association classification. Methods. T2-weighted images of arteries were obtained in 13 in vitro specimens using a 3 T MR unit (Medspec 300 Avance/Bruker, Ettlingen, Germany) combined with a dedicated MR microscopy system. Measurement parameters were: T2-weighted sequences with TR 3.5 sec, TE 15-120 msec; field of view (FOV) 1.4 x 1.4; NEX 8; matrix 192; and slice thickness 600 μm. MR measurements were compared with corresponding histologic sections. Results. We achieved excellent spatial and contrast resolution in all specimens. We found high agreement between MR images and histology with regard to the morphology and extent of intimal proliferations in all but 2 specimens. We could differentiate fibrous caps and calcifications from lipid plaque components based on differences in signal intensity in order to differentiate hard and soft atheromatous plaques. Hard plaques with predominantly intimal calcifications were found in 7 specimens, and soft plaques with a cholesterol/lipid content in 5 cases. In all specimens, hemorrhage or thrombus formation, and fibrotic and hyalinized tissue could be detected on both MR imaging and histopathology. Conclusion. High-resolution, high-field MR imaging of arterial walls demonstrates the morphologic features, volume, and extent of intimal proliferations with high spatial and contrast resolution in in vitro specimens and can differentiate hard and soft plaques

  7. IMAGE REGISTRATION OF HIGH-RESOLUTION UAV DATA: THE NEW HYPARE ALGORITHM

    Directory of Open Access Journals (Sweden)

    T. Bahr

    2013-08-01

    Full Text Available Unmanned aerial vehicles play an important role in the present-day civilian and military intelligence. Equipped with a variety of sensors, such as SAR imaging modes, E/O- and IR sensor technology, they are due to their agility suitable for many applications. Hence, the necessity arises to use fusion technologies and to develop them continuously. Here an exact image-to-image registration is essential. It serves as the basis for important image processing operations such as georeferencing, change detection, and data fusion. Therefore we developed the Hybrid Powered Auto-Registration Engine (HyPARE. HyPARE combines all available spatial reference information with a number of image registration approaches to improve the accuracy, performance, and automation of tie point generation and image registration. We demonstrate this approach by the registration of 39 still images from a high-resolution image stream, acquired with a Aeryon Photo3S™ camera on an Aeryon Scout micro-UAV™.

  8. Random-Forest Classification of High-Resolution Remote Sensing Images and Ndsm Over Urban Areas

    Science.gov (United States)

    Sun, X. F.; Lin, X. G.

    2017-09-01

    As an intermediate step between raw remote sensing data and digital urban maps, remote sensing data classification has been a challenging and long-standing research problem in the community of remote sensing. In this work, an effective classification method is proposed for classifying high-resolution remote sensing data over urban areas. Starting from high resolution multi-spectral images and 3D geometry data, our method proceeds in three main stages: feature extraction, classification, and classified result refinement. First, we extract color, vegetation index and texture features from the multi-spectral image and compute the height, elevation texture and differential morphological profile (DMP) features from the 3D geometry data. Then in the classification stage, multiple random forest (RF) classifiers are trained separately, then combined to form a RF ensemble to estimate each sample's category probabilities. Finally the probabilities along with the feature importance indicator outputted by RF ensemble are used to construct a fully connected conditional random field (FCCRF) graph model, by which the classification results are refined through mean-field based statistical inference. Experiments on the ISPRS Semantic Labeling Contest dataset show that our proposed 3-stage method achieves 86.9% overall accuracy on the test data.

  9. Automatic Object-Oriented Roundabouts Extrction from High Resolution Multispectral Images

    Science.gov (United States)

    Li, X.; Zhang, W.

    2017-09-01

    Road roundabouts, a typical class of road facilities to avoid collision, are generally not directed extracted in existing road extraction methods. This paper presents a novel four-step approach for automatic vegetated roundabout extractions from high resolution multispectral satellite images, which combines object-oriented extraction, Support Vector Machine (SVM) classification and spatial relationship estimation. Firstly, after proper preconditioning, the vegetated roundabouts are extracted by object-oriented extract algorithm in ENVI with rules that simultaneously taking area, roundness and vegetation index (NDVI) into consideration. After a certain number of experiments, the set of three items' thresholds can be found, which may stand as the general rules for vegetated roundabouts extraction in similar conditions. Next, the roads are classified using Support Vector Machine (SVM) and the outputs are several band shaped polygons. Then, the holes in road polygons will be detected by examining the topological relation in ArcGIS. Lastly, since the margin of extracted roundabout and the biggest detected hole may not strictly coincide, by comparing the distance between central points of both the extracted roundabout and the hole with the threshold, convincing determination can be made. The proposed automatic approach has been proved to have very high production accuracy that all above 85 % in each case of the test set, which is good enough for automatic vegetated roundabouts extraction from high resolution remote sensing images without manual interpretation.

  10. High resolution MR imaging of bladder cancer: new criteria for determining depth of wall invasion

    International Nuclear Information System (INIS)

    Suh, Chang Hae; Kressel, Herbert Y

    1993-01-01

    To establish new criteria to determine the depth of bladder cancer as well as to obtain the findings of each stage of bladder cancer we reviewed high resolution MR images of 18 bladder cancer patients including seven cases (26%) with superficial bladder wall invasion. All MR scans were done before biopsy or surgery. Multiple layers of the bladder wall (inner black, middle white, outer black) were demonstrated in 11 cases out of a total 18 cases. Thickening of the middle layer caused by tumor infiltration or edema of lamina propria was seen in 8 of 12 patients with stage T2 or greater, and was suggestive of superficial muscle invasion when multiple layers were demonstrated. Disruption of outer layer (as well as inner layer) and external protrusion of tumor itself were indicative of perivesical invasion. When multiple layers were not demonstrated, the depth of tumor invasion could not be judged. High resolution MR imaging can depict submucosal invasion, muscle invasion, and perivesical invasion secondary to bladder cancer

  11. A high-resolution photoelectron imaging and theoretical study of CP- and C2P.

    Science.gov (United States)

    Czekner, Joseph; Cheung, Ling Fung; Johnson, Eric L; Fortenberry, Ryan C; Wang, Lai-Sheng

    2018-01-28

    The discovery of interstellar anions has been a milestone in astrochemistry. In the search for new interstellar anions, CP - and C 2 P - are viable candidates since their corresponding neutrals have already been detected astronomically. However, scarce data exist for these negatively charged species. Here we report the electron affinities of CP and C 2 P along with the vibrational frequencies of their anions using high-resolution photoelectron imaging. These results along with previous spectroscopic data of the neutral species are used further to benchmark very accurate quartic force field quantum chemical methods that are applied to CP, CP - , C 2 P, and two electronic states of C 2 P - . The predicted electron affinities, vibrational frequencies, and rotational constants are in excellent agreement with the experimental data. The electron affinities of CP (2.8508 ± 0.0007 eV) and C 2 P (2.6328 ± 0.0006 eV) are measured accurately and found to be quite high, suggesting that the CP - and C 2 P - anions are thermodynamically stable and possibly observable. The current study suggests that the combination of high-resolution photoelectron imaging and quantum chemistry can be used to determine accurate molecular constants for exotic radical species of astronomical interest.

  12. Semantic labeling of high-resolution aerial images using an ensemble of fully convolutional networks

    Science.gov (United States)

    Sun, Xiaofeng; Shen, Shuhan; Lin, Xiangguo; Hu, Zhanyi

    2017-10-01

    High-resolution remote sensing data classification has been a challenging and promising research topic in the community of remote sensing. In recent years, with the rapid advances of deep learning, remarkable progress has been made in this field, which facilitates a transition from hand-crafted features designing to an automatic end-to-end learning. A deep fully convolutional networks (FCNs) based ensemble learning method is proposed to label the high-resolution aerial images. To fully tap the potentials of FCNs, both the Visual Geometry Group network and a deeper residual network, ResNet, are employed. Furthermore, to enlarge training samples with diversity and gain better generalization, in addition to the commonly used data augmentation methods (e.g., rotation, multiscale, and aspect ratio) in the literature, aerial images from other datasets are also collected for cross-scene learning. Finally, we combine these learned models to form an effective FCN ensemble and refine the results using a fully connected conditional random field graph model. Experiments on the ISPRS 2-D Semantic Labeling Contest dataset show that our proposed end-to-end classification method achieves an overall accuracy of 90.7%, a state-of-the-art in the field.

  13. Animals In Synchrotrons: Overcoming Challenges For High-Resolution, Live, Small-Animal Imaging

    International Nuclear Information System (INIS)

    Donnelley, Martin; Parsons, David; Morgan, Kaye; Siu, Karen

    2010-01-01

    Physiological studies in small animals can be complicated, but the complexity is increased dramatically when performing live-animal synchrotron X-ray imaging studies. Our group has extensive experience in high-resolution live-animal imaging at the Japanese SPring-8 synchrotron, primarily examining airways in two-dimensions. These experiments normally image an area of 1.8 mmx1.2 mm at a pixel resolution of 0.45 μm and are performed with live, intact, anaesthetized mice.There are unique challenges in this experimental setting. Importantly, experiments must be performed in an isolated imaging hutch not specifically designed for small-animal imaging. This requires equipment adapted to remotely monitor animals, maintain their anesthesia, and deliver test substances while collecting images. The horizontal synchrotron X-ray beam has a fixed location and orientation that limits experimental flexibility. The extremely high resolution makes locating anatomical regions-of-interest slow and can result in a high radiation dose, and at this level of magnification small animal movements produce motion-artifacts that can render acquired images unusable. Here we describe our experimental techniques and how we have overcome several challenges involved in performing live mouse synchrotron imaging.Experiments have tested different mouse strains, with hairless strains minimizing overlying skin and hair artifacts. Different anesthetics have also be trialed due to the limited choices available at SPring-8. Tracheal-intubation methods have been refined and controlled-ventilation is now possible using a specialized small-animal ventilator. With appropriate animal restraint and respiratory-gating, motion-artifacts have been minimized. The animal orientation (supine vs. head-high) also appears to affect animal physiology, and can alter image quality. Our techniques and image quality at SPring-8 have dramatically improved and in the near future we plan to translate this experience to the

  14. A Methodology of Image Segmentation for High Resolution Remote Sensing Image Based on Visual System and Markov Random Field

    Directory of Open Access Journals (Sweden)

    XU Miaozhong

    2015-02-01

    Full Text Available In consideration of the visual system's tremendous ability to perceive and identify the information, a new image segmentation method is presented which simulates the mechanism of visual system for the high resolution remote sensing image segmentation with Markov random field model. Firstly, the characteristics of the visual system have been summarized as: hierarchy, learning ability, feature detection capability and sparse coding property. Secondly, the working mechanism of visual system is simulated by wavelet transform, unsupervised clustering algorithm, feature analysis and Laplace distribution. Then, the segmentation is achieved by the visual mechanism and the Markov random field. Different satellites remote sensing images are adopted as the experimental data, and the segmentation results demonstrate the proposed method have good performance in high resolution remote sensing images.

  15. UARS High Resolution Doppler Imager (HRDI) Level 3AL V011 (UARHR3AL) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Resolution Doppler Imager (HRDI) Level 3AL data product consists of daily, 4 degree increment latitude-ordered vertical profiles of meridional and zonal...

  16. UARS High Resolution Doppler Imager (HRDI) Level 3AT V011 (UARHR3AT) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Resolution Doppler Imager (HRDI) Level 3AT data product consists of daily, 65.536 second interval time-ordered vertical profiles of meridional and zonal...

  17. High resolution, two-dimensional imaging, microchannel plate detector for use on a sounding rocket experiment

    Science.gov (United States)

    Bush, Brett C.; Cotton, Daniel M.; Siegmund, Oswald H.; Chakrabarti, Supriya; Harris, Walter; Clarke, John

    1991-01-01

    We discuss a high resolution microchannel plate (MCP) imaging detector to be used in measurements of Doppler-shifted hydrogen Lyman-alpha line emission from Jupiter and the interplanetary medium. The detector is housed in a vacuum-tight stainless steel cylinder (to provide shielding from magnetic fields) with a MgF2 window. Operating at nominal voltage, the four plate configuration provides a gain of 1.2 x 10 exp 7 electrons per incident photon. The wedge-and-strip anode has two-dimensional imaging capabilities, with a resolution of 40 microns FWHM over a one centimeter diameter area. The detector has a high quantum efficiency while retaining a low background rate. A KBr photocathode is used to enhance the quantum efficiency of the bare MCPs to a value of 35 percent at Lyman-alpha.

  18. Arrested Development: High-Resolution Imaging of Foveal Morphology in Albinism

    Science.gov (United States)

    McAllister, John T.; Dubis, Adam M.; Tait, Diane M.; Ostler, Shawn; Rha, Jungtae; Stepien, Kimberly E.; Summers, C. Gail; Carroll, Joseph

    2010-01-01

    Albinism, an inherited disorder of melanin biosynthesis, disrupts normal retinal development, with foveal hypoplasia as one of the more commonly associated ocular phenotypes. However the cellular integrity of the fovea in albinism is not well understood – there likely exist important anatomical differences that underlie phenotypic variability within the disease and that also may affect responsiveness to therapeutic intervention. Here, using spectral domain optical coherence tomography (SD-OCT) and adaptive optics (AO) retinal imaging, we obtained high-resolution images of the foveal region in six individuals with albinism. We provide a quantitative analysis of cone density and outer segment elongation demonstrating that foveal cone specialization is variable in albinism. In addition, our data reveal a continuum of foveal pit morphology, roughly aligning with schematics of normal foveal development based on post-mortem analyses. Different albinism subtypes, genetic mutations, and constitutional pigment background likely play a role in determining the degree of foveal maturation. PMID:20149815

  19. Early development in synthetic aperture lidar sensing and processing for on-demand high resolution imaging

    Science.gov (United States)

    Bergeron, Alain; Turbide, Simon; Terroux, Marc; Marchese, Linda; Harnisch, Bernd

    2017-11-01

    The quest for real-time high resolution is of prime importance for surveillance applications specially in disaster management and rescue mission. Synthetic aperture radar provides meter-range resolution images in all weather conditions. Often installed on satellites the revisit time can be too long to support real-time operations on the ground. Synthetic aperture lidar can be lightweight and offers centimeter-range resolution. Onboard airplane or unmanned air vehicle this technology would allow for timelier reconnaissance. INO has developed a synthetic aperture radar table prototype and further used a real-time optronic processor to fulfill image generation on-demand. The early positive results using both technologies are presented in this paper.

  20. Approaching bathymetry estimation from high resolution multispectral satellite images using a neuro-fuzzy technique

    Science.gov (United States)

    Corucci, Linda; Masini, Andrea; Cococcioni, Marco

    2011-01-01

    This paper addresses bathymetry estimation from high resolution multispectral satellite images by proposing an accurate supervised method, based on a neuro-fuzzy approach. The method is applied to two Quickbird images of the same area, acquired in different years and meteorological conditions, and is validated using truth data. Performance is studied in different realistic situations of in situ data availability. The method allows to achieve a mean standard deviation of 36.7 cm for estimated water depths in the range [-18, -1] m. When only data collected along a closed path are used as a training set, a mean STD of 45 cm is obtained. The effect of both meteorological conditions and training set size reduction on the overall performance is also investigated.

  1. MR imaging of the pulmonary vasculature: Cine and high-resolution techniques

    International Nuclear Information System (INIS)

    Gefter, W.B.; Hatabu, H.; Kressel, H.Y.; Axel, L.; Lenkinski, R.E.; Schiebler, M.L.; Dougherty, L.; Douglas, P.S.; Reichek, N.

    1987-01-01

    Pulmonary vessels were evaluated on 43 cine examinations (12 normals, 31 with cardiopulmonary diseases) at 1.5 T (General Electric). Arteries and veins could be differentiated by characteristic intensity fluctuations in 90%. Abnormal patterns were observed with elevated left atrial pressure, pulmonary hypertension, pulmonic stenosis, and mitral regurgitation. A small arteriovenous malformation was identified. Approaches to high-resolution imaging included surface coils, 24-cm field of view, and 256 x 256 matrix. Spin-echo (SE) sequences gated in systole or diastole, and GRASS with and without breath-holding were evaluated. Surface-coil SE diastolic images (4 NEX) visualized sixth- and seventh-generation vessels. Breath-hold GRASS showed fifth- and sixth-generation vessels without respiratory artifact. These are promising techniques for displaying the pulmonary circulation

  2. Imaging of dopamine transporters in rats using high-resolution pinhole single-photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Booij, Jan; Bruin, Kora de; Habraken, Jan B.A. [Department of Nuclear Medicine, F2N, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Voorn, Pieter [Department of Anatomy, Vrije Universiteit Medical Center, Amsterdam (Netherlands)

    2002-09-01

    To date, the vast majority of investigations on the dopaminergic system in small animals have been in vitro studies. In comparison with in vitro studies, single-photon emission tomography (SPET) or positron emission tomography (PET) imaging of the dopaminergic system in small animals has the advantage of permitting repeated studies within the same group of animals. Dopamine transporter imaging is a valuable non-invasive tool with which to investigate the integrity of dopaminergic neurons. The purpose of this study was to investigate the feasibility of assessing dopamine transporter density semi-quantitatively in rats using a recently developed high-resolution pinhole SPET system. This system was built exclusively for imaging of small animals. In this unique single-pinhole system, the animal rotates instead of the collimated detector. The system has proven to have a high spatial resolution. We performed SPET imaging with [{sup 123}I]FP-CIT to quantify striatal dopamine transporters in rat brain. In all seven studied control rats, symmetrical striatal binding to dopamine transporters was seen 2 h after injection of the radiotracer, with striatal-to-cerebellar binding ratios of approximately 3.5. In addition, test/retest variability of the striatal-to-cerebellar binding ratios was studied and found to be 14.5%. Finally, in unilaterally 6-hydroxydopamine-lesioned rats, striatal binding was only visible on the non-lesioned side. Quantitative analysis revealed that striatal-to-cerebellar SPET ratios were significantly lower on the lesioned (mean binding ratio 2.2{+-}0.2) than on the non-lesioned (mean ratio 3.1{+-}0.4) side. The preliminary results of this study indicate that semi-quantitative assessment of striatal dopamine transporter density using our recently developed high-resolution single-pinhole SPET system is feasible in living rat brain. (orig.)

  3. A clinical gamma camera-based pinhole collimated system for high resolution small animal SPECT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mejia, J.; Galvis-Alonso, O.Y., E-mail: mejia_famerp@yahoo.com.b [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Biologia Molecular; Castro, A.A. de; Simoes, M.V. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Clinica Medica; Leite, J.P. [Universidade de Sao Paulo (FMRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Medicina. Dept. de Neurociencias e Ciencias do Comportamento; Braga, J. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Div. de Astrofisica

    2010-11-15

    The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target's three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology. (author)

  4. High Resolution Seismic Imaging of the Trench Canyon Fault Zone, Mono Lake, Northeastern California

    Science.gov (United States)

    Novick, M. W.; Jayko, A. S.; Roeske, S.; McClain, J. S.; Hart, P. E.; Boyle, M.

    2009-12-01

    High resolution seismic imaging of Mono Lake, located in northeastern California, has revealed an approximately northwest striking fault in the area to the west of aerially exposed Negit Volcano. This fault, henceforth referred to as the Trench Canyon Fault (TCF), has also been mapped onshore along a correlating strike as far north as Cedar Hill Volcano, located to the northeast of the lake on the California/Nevada border. Onshore, the TCF was mapped for approximately 10 kilometers using air photos, DEM images, and standard geologic pace and compass mapping techniques. The TCF post- dates the last glacial maximum, evidenced by the cutting of wave cut benches along Cedar Hill Volcano. Relict, non-historic shorelines, left by the steady evaporation of Mono Lake beginning approximately 13k, are also repeatedly cut by the fault. Additional evidence of fault presence includes sag ponds, pressure ridges, tectonically fractured rocks, and normal fault scarps found along strike. Offshore, DEM images show a northeast striking structure to the northwest of Negit Volcano, which is co-linear with the onshore TCF. High resolution seismic imaging of the structure, using an applied acoustic/SIG mini-sparker system, reveals steeply dipping Holocene sediments, as well as volcanic deposits from active vents which have erupted in the last 1000 years, offset by the fault. Detailed structural analysis of the previously unstudied Trench Canyon Fault (TFC) and faults in the Cedar Hill region of northern California, along with seismic studies of sediments beneath Mono Lake not only allow for a better comprehension of this minor fault system, but provide greater understanding of the larger and more complex Walker Lane Shear Zone. Fault analyses, combined and correlated with those from CHV, give a better understanding of how slip is transferred into the complicated Mina defection to the east, from the dextral and normal faults along the Sierra Nevada Range front.

  5. Global Monitoring of Mountain Glaciers Using High-Resolution Spotlight Imaging from the International Space Station

    Science.gov (United States)

    Donnellan, A.; Green, J. J.; Bills, B. G.; Goguen, J.; Ansar, A.; Knight, R. L.; Hallet, B.; Scambos, T. A.; Thompson, L. G.; Morin, P. J.

    2013-12-01

    Mountain glaciers around the world are retreating rapidly, contributing about 20% to present-day sea level rise. Numerous studies have shown that mountain glaciers are sensitive to global environmental change. Temperate-latitude glaciers and snowpack provide water for over 1 billion people. Glaciers are a resource for irrigation and hydroelectric power, but also pose flood and avalanche hazards. Accurate mass balance assessments have been made for only 280 glaciers, yet there are over 130,000 in the World Glacier Inventory. The rate of glacier retreat or advance can be highly variable, is poorly sampled, and inadequately understood. Liquid water from ice front lakes, rain, melt, or sea water and debris from rocks, dust, or pollution interact with glacier ice often leading to an amplification of warming and further melting. Many mountain glaciers undergo rapid and episodic events that greatly change their mass balance or extent but are sparsely documented. Events include calving, outburst floods, opening of crevasses, or iceberg motion. Spaceborne high-resolution spotlight optical imaging provides a means of clarifying the relationship between the health of mountain glaciers and global environmental change. Digital elevation models (DEMs) can be constructed from a series of images from a range of perspectives collected by staring at a target during a satellite overpass. It is possible to collect imagery for 1800 targets per month in the ×56° latitude range, construct high-resolution DEMs, and monitor changes in high detail over time with a high-resolution optical telescope mounted on the International Space Station (ISS). Snow and ice type, age, and maturity can be inferred from different color bands as well as distribution of liquid water. Texture, roughness, albedo, and debris distribution can be estimated by measuring bidirectional reflectance distribution functions (BRDF) and reflectance intensity as a function of viewing angle. The non-sun-synchronous orbit

  6. Fast and accurate denoising method applied to very high resolution optical remote sensing images

    Science.gov (United States)

    Masse, Antoine; Lefèvre, Sébastien; Binet, Renaud; Artigues, Stéphanie; Lassalle, Pierre; Blanchet, Gwendoline; Baillarin, Simon

    2017-10-01

    Restoration of Very High Resolution (VHR) optical Remote Sensing Image (RSI) is critical and leads to the problem of removing instrumental noise while keeping integrity of relevant information. Improving denoising in an image processing chain implies increasing image quality and improving performance of all following tasks operated by experts (photo-interpretation, cartography, etc.) or by algorithms (land cover mapping, change detection, 3D reconstruction, etc.). In a context of large industrial VHR image production, the selected denoising method should optimized accuracy and robustness with relevant information and saliency conservation, and rapidity due to the huge amount of data acquired and/or archived. Very recent research in image processing leads to a fast and accurate algorithm called Non Local Bayes (NLB) that we propose to adapt and optimize for VHR RSIs. This method is well suited for mass production thanks to its best trade-off between accuracy and computational complexity compared to other state-of-the-art methods. NLB is based on a simple principle: similar structures in an image have similar noise distribution and thus can be denoised with the same noise estimation. In this paper, we describe in details algorithm operations and performances, and analyze parameter sensibilities on various typical real areas observed in VHR RSIs.

  7. AN EVALUATION OF FEATURE LEARNING METHODS FOR HIGH RESOLUTION IMAGE CLASSIFICATION

    Directory of Open Access Journals (Sweden)

    P. Tokarczyk

    2012-07-01

    Full Text Available Automatic image classification is one of the fundamental problems of remote sensing research. The classification problem is even more challenging in high-resolution images of urban areas, where the objects are small and heterogeneous. Two questions arise, namely which features to extract from the raw sensor data to capture the local radiometry and image structure at each pixel or segment, and which classification method to apply to the feature vectors. While classifiers are nowadays well understood, selecting the right features remains a largely empirical process. Here we concentrate on the features. Several methods are evaluated which allow one to learn suitable features from unlabelled image data by analysing the image statistics. In a comparative study, we evaluate unsupervised feature learning with different linear and non-linear learning methods, including principal component analysis (PCA and deep belief networks (DBN. We also compare these automatically learned features with popular choices of ad-hoc features including raw intensity values, standard combinations like the NDVI, a few PCA channels, and texture filters. The comparison is done in a unified framework using the same images, the target classes, reference data and a Random Forest classifier.

  8. [Diagnostic value of high-resolution computed tomography imaging in congenital inner ear malformations].

    Science.gov (United States)

    Sun, Xiaowei; Ding, Yuanping; Zhang, Jianji; Chen, Ying; Xu, Anting; Dou, Fenfen; Zhang, Zihe

    2007-02-01

    To observe the inner ear structure with volume rendering (VR) reconstruction and to evaluate the role of high-resolution computed tomography (HRCT) in congenital inner ear malformations. HRCT scanning was performed in 10 patients (20 ears) without ear disease (control group) and 7 patients (11 ears) with inner ear malformations (IEM group) and the original data was processed with VR reconstruction. The inner ear osseous labyrinth structure in the images generated by these techniques was observed respectively in the normal ears and malformation ears. The inner ear osseous labyrinth structure and the relationship was displayed clearly in VR imaging in the control group,meanwhile, characters and degree of malformed structure were also displayed clearly in the IEA group. Of seven patients (11 ears) with congenital inner ear malformations, the axial, MPR and VR images can display the site and degree in 9 ears. VR images were superior to the axial images in displaying the malformations in 2 ears with the small lateral semicircular canal malformations. The malformations included Mondini deformity (7 ears), vestibular and semicircular canal malformations (3 ears), vestibular aqueduct dilate (7 ears, of which 6 ears accompanied by other malformations) , the internal auditory canal malformation (2 ears, all accompanied by other malformations). HRCT can display the normal structure of bone inner ear through high quality VR reconstructions. VR images can also display the site and degree of the malformations three-dimensionally and intuitively. HRCT is valuable in diagnosing the inner ear malformation.

  9. Human subthalamic nucleus: evaluation with high-resolution MR imaging at 3.0 T

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, Mika; Hayashida, Yoshiko; Hirai, Toshinori; Okuda, Tomoko; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto (Japan); Korogi, Yukunori; Kakeda, Shingo; Moriya, Junji; Ohnari, Norihiro; Sato, Toru [University of Occupational and Environmental Health, Department of Radiology, School of Medicine, Yahatanishi-ku, Kitakyushu (Japan)

    2008-08-15

    The purpose of this study was to compare the visibility of the normal subthalamic nucleus (STN) between fast spin-echo T2-weighted (FSE T2-W) images and fast short inversion time inversion-recovery (FSTIR) images, and to assess the age-related changes of the STN at 3.0 T. We evaluated high-resolution FSE T2-W and FSTIR images in 24 neurologically normal subjects. Using both sequences, we assessed the visibility of the margins of the STN, and calculated the difference in signal intensity between the STN and structures adjacent to the STN. Then, to assess the age-related changes of the STN, we calculated the contrast-to-noise ratio between the STN and the white matter, and measured the position, length, and height of the STN. All data were statistically evaluated. The visibility of the lower margin of the STN was significantly better on the FSTIR images than on the FSE T2-W images (P=0.0001), while the visibility of other margins was significantly better on the FSE T2-W images than on the FSTIR mages (P=0.002). The difference in signal intensity between the STN and substantia nigra was significantly greater on the FSTIR images than on the FSE T2-W images (P<0.0001). The distance from the midline to the lateral border of the STN increased with age (FSE T2-W images: left r=0.4916, P=0.015; right r=0.4442, P=0.030). The combined reading of both FSE T2-W and FSTIR images at 3 T will improve the identification of the STN. The age-related positional change of the STN should be considered in target determination for deep brain stimulation procedures. (orig.)

  10. Human subthalamic nucleus: evaluation with high-resolution MR imaging at 3.0 T.

    Science.gov (United States)

    Kitajima, Mika; Korogi, Yukunori; Kakeda, Shingo; Moriya, Junji; Ohnari, Norihiro; Sato, Toru; Hayashida, Yoshiko; Hirai, Toshinori; Okuda, Tomoko; Yamashita, Yasuyuki

    2008-08-01

    The purpose of this study was to compare the visibility of the normal subthalamic nucleus (STN) between fast spin-echo T2-weighted (FSE T2-W) images and fast short inversion time inversion-recovery (FSTIR) images, and to assess the age-related changes of the STN at 3.0 T. We evaluated high-resolution FSE T2-W and FSTIR images in 24 neurologically normal subjects. Using both sequences, we assessed the visibility of the margins of the STN, and calculated the difference in signal intensity between the STN and structures adjacent to the STN. Then, to assess the age-related changes of the STN, we calculated the contrast-to-noise ratio between the STN and the white matter, and measured the position, length, and height of the STN. All data were statistically evaluated. The visibility of the lower margin of the STN was significantly better on the FSTIR images than on the FSE T2-W images (P = 0.0001), while the visibility of other margins was significantly better on the FSE T2-W images than on the FSTIR mages (P = 0.002). The difference in signal intensity between the STN and substantia nigra was significantly greater on the FSTIR images than on the FSE T2-W images (P W images: left r = 0.4916, P = 0.015; right r = 0.4442, P = 0.030). The combined reading of both FSE T2-W and FSTIR images at 3 T will improve the identification of the STN. The age-related positional change of the STN should be considered in target determination for deep brain stimulation procedures.

  11. High-resolution US and MR imaging of peroneal tendon injuries.

    Science.gov (United States)

    Taljanovic, Mihra S; Alcala, Jennifer N; Gimber, Lana H; Rieke, Joshua D; Chilvers, Margaret M; Latt, L Daniel

    2015-01-01

    Injuries of the peroneal tendon complex are common and should be considered in every patient who presents with chronic lateral ankle pain. These injuries occur as a result of trauma (including ankle sprains), in tendons with preexisting tendonopathy, and with repetitive microtrauma due to instability. The peroneus brevis and peroneus longus tendons are rarely torn simultaneously. Several anatomic variants, including a flat or convex fibular retromalleolar groove, hypertrophy of the peroneal tubercle at the lateral aspect of the calcaneus, an accessory peroneus quartus muscle, a low-lying peroneus brevis muscle belly, and an os peroneum, may predispose to peroneal tendon injuries. High-resolution 1.5-T and 3-T magnetic resonance (MR) imaging with use of dedicated extremity coils and high-resolution ultrasonography (US) with high-frequency linear transducers and dynamic imaging are proved to adequately depict the peroneal tendons for evaluation and can aid the orthopedic surgeon in injury management. An understanding of current treatment approaches for partial- and full-thickness peroneal tendon tears, subluxation and dislocation of these tendons with superior peroneal retinaculum (SPR) injuries, intrasheath subluxations, and peroneal tendonopathy and tenosynovitis can help physicians achieve a favorable outcome. Patients with low functional demands do well with conservative treatment, while those with high functional demands may benefit from surgery if nonsurgical treatment is unsuccessful. Radiologists should recognize the normal anatomy and specific pathologic conditions of the peroneal tendons at US and MR imaging and understand the various treatment options for peroneal tendon and SPR superior peroneal retinaculum injuries. Online supplemental material is available for this article. RSNA, 2015

  12. High-Resolution Infrared Imaging and Polarimetry plus Spectroscopy of Evolved Red and Yellow Supergiants

    Science.gov (United States)

    Gordon, Michael Scott; Humphreys, Roberta; Jones, Terry J.; Gehrz, Robert D.

    2018-01-01

    To what extent mass loss and periods of enhanced stellar outflow can influence the terminal state of the most massive stars remains an outstanding question in the fields of stellar physics, chemical enrichment of the Local Universe, andsupernova research. For my dissertation, I focus on characterizing the stellar ejecta around supergiants through a combination of observing techniques. Using the LBT, MMT, IRTF, VLT, and SOFIA observatories, I have performed high-resolution imaging, spectroscopy, and polarimetry—methods that provide us with keen insight on mass-loss histories and 3D morphology of the Local Group's most fascinating stars.Based on spectroscopic evidence for mass loss in the optical and the presence ofcircumstellar (CS) dust in infrared SEDs, we find that 30%–40% of observed yellow supergiants in M31 and M33 are likely in a post-RSG state. We also presentnear-IR spectra from IRTF/SPeX of optically-obscured RSGs in M33. These IR-bright sources likely have some of the highest mass-loss rates and are self-obscured in the optical by their own CS ejecta. For Galactic red supergiants (RSGs), we are able to observe the gas and CS dust ejecta both close in to the central star and at larger distances. The resulting radial profiles are valuable probes on timescale for the ejecta when combined with radiative-transfer models. We find evidence for both variable/high mass-loss events and constant mass loss over the last few thousand years. Finally, we discuss the use of high-resolution imaging polarimetry with VLT/NACO of two co-eval RSG clusters toward the Galactic center. The resulting polarized intensity images in the near-infrared provide unprecedented spatial and contrast resolution of the scattered light from extended nebular material.

  13. Design of optoelectronic imaging system with high resolution and large field-of-view based on dual CMOS

    Science.gov (United States)

    Cheng, Hanglin; Hao, Qun; Hu, Yao; Cao, Jie; Wang, Shaopu; Li, Lin

    2016-10-01

    With the advantages of high resolution, large field of view and compacted size, optoelectronic imaging sensors are widely used in many fields, such as robot's navigation, industrial measurement and remote sensing. Many researchers pay more attention to improve the comprehensive performances of imaging sensors, including large field of view (FOV), high resolution, compact size and high imaging efficiency, etc. One challenge is the tradeoff between high resolution and large field of view simultaneously considering compacted size. In this paper, we propose an optoelectronic imaging system combining the lenses of short focal length and long focal length based on dual CMOS to simulate the characters of human eyes which observe object within large FOV in high resolution. We design and optimize the two lens, the lens of short focal length is used to search object in a wide field and the long one is responsible for high resolution imaging of the target area. Based on a micro-CMOS imaging sensor with low voltage differential transmission technology-MIPI (Mobile Industry Processor Interface), we design the corresponding circuits to realize collecting optical information with high speed. The advantage of the interface is to help decreasing power consumption, improving transmission efficiency and achieving compacted size of imaging sensor. Meanwhile, we carried out simulations and experiments to testify the optoelectronic imaging system. The results show that the proposed method is helpful to improve the comprehensive performances of optoelectronic imaging sensors.

  14. Multichannel High Resolution Wide Swath SAR Imaging for Hypersonic Air Vehicle with Curved Trajectory.

    Science.gov (United States)

    Zhou, Rui; Sun, Jinping; Hu, Yuxin; Qi, Yaolong

    2018-01-31

    Synthetic aperture radar (SAR) equipped on the hypersonic air vehicle in near space has many advantages over the conventional airborne SAR. However, its high-speed maneuvering characteristics with curved trajectory result in serious range migration, and exacerbate the contradiction between the high resolution and wide swath. To solve this problem, this paper establishes the imaging geometrical model matched with the flight trajectory of the hypersonic platform and the multichannel azimuth sampling model based on the displaced phase center antenna (DPCA) technology. Furthermore, based on the multichannel signal reconstruction theory, a more efficient spectrum reconstruction model using discrete Fourier transform is proposed to obtain the azimuth uniform sampling data. Due to the high complexity of the slant range model, it is difficult to deduce the processing algorithm for SAR imaging. Thus, an approximate range model is derived based on the minimax criterion, and the optimal second-order approximate coefficients of cosine function are obtained using the two-population coevolutionary algorithm. On this basis, aiming at the problem that the traditional Omega-K algorithm cannot compensate the residual phase with the difficulty of Stolt mapping along the range frequency axis, this paper proposes an Exact Transfer Function (ETF) algorithm for SAR imaging, and presents a method of range division to achieve wide swath imaging. Simulation results verify the effectiveness of the ETF imaging algorithm.

  15. High-Resolution X-Ray Lensless Imaging by Differential Holographic Encoding

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Diling [Stanford Univ., CA (United States). Dept. of Applied Physics; SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. for Material and Energy Science; Guizar-Sicairos, Manuel [Univ. of Rochester, NY (United States). Inst. of Optics; Wu, Benny [Stanford Univ., CA (United States). Dept. of Applied Physics; SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. for Material and Energy Science; Scherz, Andreas [SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Inst. for Material and Energy Science; Acremann, Yves [SLAC National Accelerator Lab., Menlo Park, CA (United States). Photon Ultrafast Laser Science and Engineering Inst. (PULSE); Tyliszczak, Tolek [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Fischer, Peter [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Center for X-ray Optics; Friedenberger, Nina [Universitat Duisburg-Essen (Germany). Dept. of Physics and Center for Nanointegration Duisburg-Essen (CeNIDE); Ollefs, Katharina [Universitat Duisburg-Essen (Germany). Dept. of Physics and Center for Nanointegration Duisburg-Essen (CeNIDE); Farle, Michael [Universitat Duisburg-Essen (Germany). Dept. of Physics and Center for Nanointegration Duisburg-Essen (CeNIDE); Fienup, James R. [Univ. of Rochester, NY (United States). Inst. of Optics; Stöhr, Joachim [SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source (LCLS)

    2010-07-01

    X-ray free electron lasers (X-FELs) will soon offer femtosecond pulses of laterally coherent x-rays with sufficient intensity to record single-shot coherent scattering patterns for nanoscale imaging. Pulse trains created by split and- delay techniques even open the door for cinematography on unprecedented nanometer length and femtosecond time scales. A key to real space ultrafast motion pictures is fast and reliable inversion of the recorded reciprocal space scattering patterns. Here we for the first time demonstrate in the x-ray regime the power of a novel technique for lensless high resolution imaging, previously suggested by Guizar-Sicairos and Fienup termed holography with extended reference by autocorrelation linear differential operation, HERALD0. We have achieved superior resolution over conventional x-ray Fourier transform holography (FTH) without sacrifices in SNR or significant increase in algorithmic complexity. By combining images obtained from individual sharp features on an extended reference, we further show that the resolution can be even extended beyond the reference fabrication limits. Direct comparison to iterative phase retrieval image reconstruction and images recorded with state of-the-art zone plate microscopes is presented. Our results demonstrate the power of HERALDO as a favorable candidate for robust inversion of single-shot coherent scattering patterns.

  16. High resolution x-ray lensless imaging by differential holographic encoding

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, D.; Guizar-Sicairos, M.; Wu, B.; Scherz, A.; Acremann, Y.; Tylisczcak, T.; Fischer, P.; Friedenberger, N.; Ollefs, K.; Farle, M.; Fienup, J. R.; Stohr, J.

    2009-11-02

    X-ray free electron lasers (X-FEL{sub s}) will soon offer femtosecond pulses of laterally coherent x-rays with sufficient intensity to record single-shot coherent scattering patterns for nanoscale imaging. Pulse trains created by splitand-delay techniques even open the door for cinematography on unprecedented nanometer length and femtosecond time scales. A key to real space ultrafast motion pictures is fast and reliable inversion of the recorded reciprocal space scattering patterns. Here we for the first time demonstrate in the x-ray regime the power of a novel technique for lensless high resolution imaging, previously suggested by Guizar-Sicairos and Fienup termed holography with extended reference by autocorrelation linear differential operation, HERALD0. We have achieved superior resolution over conventional x-ray Fourier transform holography (FTH) without sacrifices in SNR or significant increase in algorithmic complexity. By combining images obtained from individual sharp features on an extended reference, we further show that the resolution can be even extended beyond the reference fabrication limits. Direct comparison to iterative phase retrieval image reconstruction and images recorded with stateof- the-art zone plate microscopes is presented. Our results demonstrate the power of HERALDO as a favorable candidate for robust inversion of single-shot coherent scattering patterns.

  17. USING MORPHOLOGICAL DIFFERENTIAL ATTRIBUTE PROFILES FOR CHANGE CATEGORIZATION IN HIGH RESOLUTION SAR IMAGES

    Directory of Open Access Journals (Sweden)

    M. Boldt

    2013-04-01

    Full Text Available Change detection in urban and suburban areas through remote sensing satellite imagery is an important topic. Furthermore, it is of special interest to derive information on the category of detected changes is of special interest. In Boldt et al. (2012, a fullyautomatic change detection method based on a morphological filtered ratio image was presented. This filter step is accomplished by an alternating sequential filter (ASF, which supports the knowledge-driven analysis of the scene. For example, the focus can be set on small-scaled changes caused by vehicles or smaller construction sites. The change detection itself is performed using the automatic threshold method shown in Sahoo et al. (2004 considering the entropies of the fore- and background of the filtered ratio image. In contrast, the presented approach makes use of morphological differential attribute profiles (DAPs to compare changes detected in high resolution (HR TerraSAR-X (TSX amplitude images of Greding (Germany. DAPs are the derivatives of morphological attribute profiles (APs. APs are calculated by applying iteratively attribute openings and/or closings to an input image. Attribute openings (resp. closings themselves are a combination of connected openings (closings and trivial openings (closings. DAPs provide the opportunity to derive typical signatures for each pixel of the entire image (Dalla Mura et al., 2010, and, as a consequence, for each detected change segment. Aiming on the categorization of changes, it is shown in this paper that the DAPs represent a promising method for detecting changes with similar semantics automatically.

  18. Statistical list-mode image reconstruction for the high resolution research tomograph

    International Nuclear Information System (INIS)

    Rahmim, A; Lenox, M; Reader, A J; Michel, C; Burbar, Z; Ruth, T J; Sossi, V

    2004-01-01

    We have investigated statistical list-mode reconstruction applicable to a depth-encoding high resolution research tomograph. An image non-negativity constraint has been employed in the reconstructions and is shown to effectively remove the overestimation bias introduced by the sinogram non-negativity constraint. We have furthermore implemented a convergent subsetized (CS) list-mode reconstruction algorithm, based on previous work (Hsiao et al 2002 Conf. Rec. SPIE Med. Imaging 4684 10-19; Hsiao et al 2002 Conf. Rec. IEEE Int. Symp. Biomed. Imaging 409-12) on convergent histogram OSEM reconstruction. We have demonstrated that the first step of the convergent algorithm is exactly equivalent (unlike the histogram-mode case) to the regular subsetized list-mode EM algorithm, while the second and final step takes the form of additive updates in image space. We have shown that in terms of contrast, noise as well as FWHM width behaviour, the CS algorithm is robust and does not result in limit cycles. A hybrid algorithm based on the ordinary and the convergent algorithms is also proposed, and is shown to combine the advantages of the two algorithms (i.e. it is able to reach a higher image quality in fewer iterations while maintaining the convergent behaviour), making the hybrid approach a good alternative to the ordinary subsetized list-mode EM algorithm

  19. Advances in the staging of renal cell carcinoma with high-resolution imaging

    International Nuclear Information System (INIS)

    Hallscheidt, P.; Noeldge, G.; Schawo, S.; Kauffmann, G.; Palmowski, M.; Bartling, S.; Pfitzenmaier, J.

    2007-01-01

    Modern imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) allow high-resolution imaging of the abdomen. Modern scanners made high temporal as well as high spatial resolution available. Therapeutic approaches to the treatment of renal cell carcinoma have been improved over the recent years. Besides conventional and open laparoscopic tumor nephrectomy and nephron sparing, surgical approaches such as local tumor cryotherapy and radiofrequency ablation (RF) are ablative modalities and are used increasingly. Improved anesthesiological methods and new surgical approaches also allow curative treatment in extended tumors. Prerequisites for preoperative imaging modalities include visualization of the kidney tumor as well as its staging. Tumor-related infiltration of the renal pelvis or invasion of the perinephric fat and the renal hilus has to be excluded prior to nephron sparing surgery. In cases with extended tumors with infiltration of the inferior vena cava, it is necessary to visualize the exact extension of the tumor growth towards the right atrium in the vena cava. The radiologist should be informed about the diagnostic possibilities and limitations of the imaging modalities of CT and MRI in order to support the urologist in the planning and performance of surgical therapeutical approaches. (orig.)

  20. High-resolution magnetic resonance imaging of arthritic pathology in the rat knee

    International Nuclear Information System (INIS)

    Carpenter, T.A.; Everett, J.R.; Hall, L.D.; Harper, G.P.; Hodgson, R.J.; James, M.F.; Watson, P.J.

    1994-01-01

    High-resolution magnetic resonance imaging (MRI) has been used to visualise the changes that occur in both soft tissue and bone during antigen-induced, monoarticular arthritis (AIMA) of the rat knee. Extensive optimisation studies were performed in order to minimise the time of the experiments and to maximise both the signal-to-noise ratio and the contrast in the MR images. The study was cross-sectional rather than longitudinal and at each of the 13 time points studied during the progression of the disease, corresponding X-radiographs and histological sections were obtained. Interpretation of the spin echo MR images was aided by the use of chemical shift-selective imaging, magnetisation transfer contrast and relaxation time experiments, as well as by correlation with the histology and X-radiography data. The MR images clearly show invasion of the synovium by an inflammatory pannus which spreads over the articular cartilage and invades the bone, leading to erosion and later remodelling. Two distinct types of bony erosion were observed: focal erosions, especially at the margins of the joint, and subchondral erosions. It is concluded that MRI provides a sensitive, non-invasive method for investigating both early-stage inflammatory changes and late-stage bony changes in the knee joints of the arthritic rat. (orig.)

  1. A Saliency Guided Semi-Supervised Building Change Detection Method for High Resolution Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Bin Hou

    2016-08-01

    Full Text Available Characterizations of up to date information of the Earth’s surface are an important application providing insights to urban planning, resources monitoring and environmental studies. A large number of change detection (CD methods have been developed to solve them by utilizing remote sensing (RS images. The advent of high resolution (HR remote sensing images further provides challenges to traditional CD methods and opportunities to object-based CD methods. While several kinds of geospatial objects are recognized, this manuscript mainly focuses on buildings. Specifically, we propose a novel automatic approach combining pixel-based strategies with object-based ones for detecting building changes with HR remote sensing images. A multiresolution contextual morphological transformation called extended morphological attribute profiles (EMAPs allows the extraction of geometrical features related to the structures within the scene at different scales. Pixel-based post-classification is executed on EMAPs using hierarchical fuzzy clustering. Subsequently, the hierarchical fuzzy frequency vector histograms are formed based on the image-objects acquired by simple linear iterative clustering (SLIC segmentation. Then, saliency and morphological building index (MBI extracted on difference images are used to generate a pseudo training set. Ultimately, object-based semi-supervised classification is implemented on this training set by applying random forest (RF. Most of the important changes are detected by the proposed method in our experiments. This study was checked for effectiveness using visual evaluation and numerical evaluation.

  2. HIGH RESOLUTION 36 GHz IMAGING OF THE SUPERNOVA REMNANT OF SN 1987A

    International Nuclear Information System (INIS)

    Potter, T. M.; Staveley-Smith, L.; Zanardo, G.; Ng, C.-Y.; Gaensler, B. M.; Ball, Lewis; Kesteven, M. J.; Manchester, R. N.; Tzioumis, A. K.

    2009-01-01

    The aftermath of supernova (SN) 1987A continues to provide spectacular insights into the interaction between an SN blastwave and its circumstellar environment. We here present 36 GHz observations from the Australia Telescope Compact Array of the radio remnant of SN 1987A. These new images, taken in 2008 April and 2008 October, substantially extend the frequency range of an ongoing monitoring and imaging program conducted between 1.4 and 20 GHz. Our 36.2 GHz images have a diffraction-limited angular resolution of 0.''3-0.''4, which covers the gap between high resolution, low dynamic range VLBI images of the remnant and low resolution, high dynamic range images at frequencies between 1 and 20 GHz. The radio morphology of the remnant at 36 GHz is an elliptical ring with enhanced emission on the eastern and western sides, similar to that seen previously at lower frequencies. Model fits to the data in the Fourier domain show that the emitting region is consistent with a thick inclined torus of mean radius 0.''85, and a 2008 October flux density of 27 ± 6 mJy at 36.2 GHz. The spectral index for the remnant at this epoch, determined between 1.4 GHz and 36.2 GHz, is α = -0.83. There is tentative evidence for an unresolved central source with flatter spectral index.

  3. Pinhole SPECT: high resolution imaging of brain tumours in small laboratory animals

    International Nuclear Information System (INIS)

    Franceschim, M.; Bokulic, T.; Kusic, Z.; Strand, S.E.; Erlandsson, K.

    1994-01-01

    The performance properties of pinhole SPECT and the application of this technology to evaluate radionuclide uptake in brain in small laboratory animals were investigated. System sensitivity and spatial resolution measurements of a rotating scintillation camera system were made for a low energy pinhole collimator equipped with 2.0 mm aperture pinhole insert. Projection data were acquired at 4 degree increments over 360 degrees in the step and shoot mode using a 4.5 cm radius of rotation. Pinhole planar and SPECT imaging were obtained to evaluate regional uptake of Tl-201, Tc-99m-MIBI, Tc-99m-HMPAO and Tc-99m-DTPA in tumor and control regions of the brain in a primary brain tumor model in Fisher 344 rats. Pinhole SPECT images were reconstructed using a modified cone- beam algorithm developed from a two dimensional fan-beam filtered backprojection algorithm. The reconstructed transaxial resolution of 2.8 FWHM and system sensitivity of 0.086 c/s/kBq with the 2.0 mm pinhole collimator aperture were measured. Tumor to non-tumor uptake ratios at 19-28 days post tumor cell inoculation varied by a factor > 20:1 on SPECT images. Pinhole SPECT provides an important new approach for performing high resolution imaging: the resolution properties of pinhole SPECT are superior to those which have been achieved with conventional SPECT or PET imaging technologies. (author)

  4. Frequency and failure of high-resolution monitors in a filmless imaging department

    Science.gov (United States)

    Siegel, Eliot L.; Reiner, Bruce I.; Cadogan, Michael

    1999-07-01

    The purpose of this study was to assess the rate of failure of the high resolution monitors used for primary diagnosis in a filmless radiology department and to analyze the type of problems encountered as well as the action taken to report the monitors. Data were collected from PACS service logs to determine rates of monitor adjustment and replacement, the symptoms reported, and the action taken. Analysis of monitor service records demonstrated a high rate of monitor replacement resulting in a relatively short 'life expectancy of 2.4 years. The result of this study support our subjective impression and those of other colleagues in the PACS community of an unacceptably high monitor failure rate with 2,000 pixel monitors used for primary diagnosis. Requests for proposals for PACS and service contracts must carefully specify requirements for monitor images quality and conditions under which the vendor is required to replace these monitors.

  5. Prolactin-secreting pituitary microadenomas: inaccuracy of high-resolution CT imaging

    International Nuclear Information System (INIS)

    Davis, P.C.; Hoffman, J.C. Jr.; Tindall, G.T.; Braun, I.F.

    1985-01-01

    Computed tomographic (CT) and surgical findings were correlated retrospectively in 51 patients with preoperative diagnoses of prolactin-secreting pituitary microadenomas. Thirty-nine had microadenomas at surgery. Twenty-three had identifiable discrete lesions. Of these, 21 had microadenomas and two did not; these two groups could not be distinguished reliably. Six patients with proven microadenomas had normal CT scans. Focal hypodense lesions, sellar floor erosion, infundibulum displacement, gland height greater than 8 mm, and an abnormal diaphragma sellae configuration are neither sensitive nor specific findings or microadenoma. A significant number of patients with proven microadenomas has few or none of these abnormalities. Thus, recognition of prolactin microadenoma may not be possible by CT alone, even with high-resolution direct coronal imaging

  6. Propagation-based phase-contrast tomography for high-resolution lung imaging with laboratory sources

    Energy Technology Data Exchange (ETDEWEB)

    Krenkel, Martin, E-mail: mkrenke@gwdg.de; Töpperwien, Mareike; Salditt, Tim, E-mail: tsaldit@gwdg.de [Institute for X-Ray Physics, University of Göttingen, 37077 Göttingen (Germany); Dullin, Christian [Institute of Diagnostic and Interventional Radiology, University Medical Center Göttingen, 37075 Göttingen (Germany); Alves, Frauke [Institute of Diagnostic and Interventional Radiology, University Medical Center Göttingen, 37075 Göttingen (Germany); Department of Haematology and Medical Oncology, Medical Center Göttingen, 37075 Göttingen (Germany); Department of Molecular Biology of Neuronal Signals, Max-Planck-Institute of Experimental Medicine, 37075 Göttingen (Germany)

    2016-03-15

    We have performed high-resolution phase-contrast tomography on whole mice with a laboratory setup. Enabled by a high-brilliance liquid-metal-jet source, we show the feasibility of propagation-based phase contrast in local tomography even in the presence of strongly absorbing surrounding tissue as it is the case in small animal imaging of the lung. We demonstrate the technique by reconstructions of the mouse lung for two different fields of view, covering the whole organ, and a zoom to the local finer structure of terminal airways and alveoli. With a resolution of a few micrometers and the wide availability of the technique, studies of larger biological samples at the cellular level become possible.

  7. Propagation-based phase-contrast tomography for high-resolution lung imaging with laboratory sources

    Directory of Open Access Journals (Sweden)

    Martin Krenkel

    2016-03-01

    Full Text Available We have performed high-resolution phase-contrast tomography on whole mice with a laboratory setup. Enabled by a high-brilliance liquid-metal-jet source, we show the feasibility of propagation-based phase contrast in local tomography even in the presence of strongly absorbing surrounding tissue as it is the case in small animal imaging of the lung. We demonstrate the technique by reconstructions of the mouse lung for two different fields of view, covering the whole organ, and a zoom to the local finer structure of terminal airways and alveoli. With a resolution of a few micrometers and the wide availability of the technique, studies of larger biological samples at the cellular level become possible.

  8. Polarization monitoring device for the High-Resolution Imaging Spectrometer (HRIS)

    Science.gov (United States)

    Schwarzer, Horst H.; Blechinger, Fritz; Menardi, Alberto S.

    1995-06-01

    The requirements concerning the radiometric accuracy of optical remote sensing systems for earth and environmental observations especially to high resolution imaging spectro- radiometers are increasing more and more. Accurate and conscientious on-ground and in-flight calibration of the sensors is one of the baselines to meet this requirement. From this point of view the polarization sensitivity of the sensors plays an important role because it is present more or less every time. Polarization sensitivity and its changes affect directly the radiometric accuracy of the estimated radiances of the polarized radiation coming from the scenes under investigation. In this paper an equipment for in-flight monitoring the polarization sensitivity of the sensor as part of the calibration procedure is presented. It can be used for measuring the plarization state of the incoming radiation too.

  9. High resolution neurography of the brachial plexus by 3 Tesla magnetic resonance imaging.

    Science.gov (United States)

    Cejas, C; Rollán, C; Michelin, G; Nogués, M

    2016-01-01

    The study of the structures that make up the brachial plexus has benefited particularly from the high resolution images provided by 3T magnetic resonance scanners. The brachial plexus can have mononeuropathies or polyneuropathies. The mononeuropathies include traumatic injuries and trapping, such as occurs in thoracic outlet syndrome due to cervical ribs, prominent transverse apophyses, or tumors. The polyneuropathies include inflammatory processes, in particular chronic inflammatory demyelinating polyneuropathy, Parsonage-Turner syndrome, granulomatous diseases, and radiation neuropathy. Vascular processes affecting the brachial plexus include diabetic polyneuropathy and the vasculitides. This article reviews the anatomy of the brachial plexus and describes the technique for magnetic resonance neurography and the most common pathologic conditions that can affect the brachial plexus. Copyright © 2016 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  10. Simultaneous change region and pattern identification for very high-resolution images

    Science.gov (United States)

    Huo, Chunlei; Huo, Leigang; Zhou, Zhixin; Pan, Chunhong

    2017-10-01

    By taking advantages of fine details obtained by the improved spatial resolution, very high-resolution images are promising for detecting change regions and identifying change patterns. However, high overlaps between different change patterns and the complexities of multiclass classification make it difficult to reliably separate change features. A framework named simultaneous change region and pattern identification (SCRAPI) is proposed for simultaneously detecting change regions and identifying change patterns, whose components are aimed at capturing overlaps between change patterns and reducing overlaps driven by user-specific interests. To validate the effectiveness of SCRAPI, a supervised approach is illustrated within this framework, which starts with modeling the relationship between change features by interclass couples and intraclass couples, followed by metric learning where structural sparsity is captured by the mixed norm. Experiments demonstrate the effectiveness of the proposed approach.

  11. 3D-OSEM iterative image reconstruction for high-resolution PET using precalculated system matrix

    International Nuclear Information System (INIS)

    Ortuno, Juan E.; Guerra-Gutierrez, Pedro; Rubio, Jose L.; Kontaxakis, George; Santos, Andres

    2006-01-01

    An efficient iterative image reconstruction methodology is presented, adapted to high-resolution flat-head 3D positron emission tomography cameras. It is based on the ordered subsets expectation maximization algorithm and applies to systems with axial symmetry. The associated system matrix is calculated off-line, including a model of the γ-event detection in the crystal, taking into account photoelectric effect and Compton scattering interactions. The nonzero elements of the sparse system matrix are stored in disc in an efficient way that allows the fast sequential access to the matrix elements during the reconstruction. A detailed calculation is performed for the voxels corresponding to central plane within the field of view (FOV) of the camera and the remaining values of the system matrix are obtained via translations based on the symmetries of the system along the axial dimension. GATE-based simulations have been used for the validation of the results

  12. Implementation and performance of an optical motion tracking system for high resolution brain PET imaging

    Science.gov (United States)

    Lopresti, B. J.; Russo, A.; Jones, W. F.; Fisher, T.; Crouch, D. G.; Altenburger, D. E.; Townsend, D. W.

    1999-12-01

    Head motion during PET scanning is widely regarded as a source of image degradation and resolution loss. Recent improvements in the spatial resolution of state-of-the-art tomographs may be compromised by patient motion during scanning, as these high resolution data will be increasingly susceptible to smaller movements of the head. The authors have developed an opto-electronic motion tracking system based on commercially-available technology that is capable of very accurate real-time measurements of the position and orientation of the patient's head. These positions are transformed to the reference frame of the PET scanner, and could potentially be used to provide motion correction of list-mode emission data on an event-by-event basis.

  13. High-resolution, in vivo magnetic resonance imaging of Drosophila at 18.8 Tesla.

    Directory of Open Access Journals (Sweden)

    Brian Null

    Full Text Available High resolution MRI of live Drosophila was performed at 18.8 Tesla, with a field of view less than 5 mm, and administration of manganese or gadolinium-based contrast agents. This study demonstrates the feasibility of MR methods for imaging the fruit fly Drosophila with an NMR spectrometer, at a resolution relevant for undertaking future studies of the Drosophila brain and other organs. The fruit fly has long been a principal model organism for elucidating biology and disease, but without capabilities like those of MRI. This feasibility marks progress toward the development of new in vivo research approaches in Drosophila without the requirement for light transparency or destructive assays.

  14. Tablet disintegration studied by high-resolution real-time magnetic resonance imaging.

    Science.gov (United States)

    Quodbach, Julian; Moussavi, Amir; Tammer, Roland; Frahm, Jens; Kleinebudde, Peter

    2014-01-01

    The present work employs recent advances in high-resolution real-time magnetic resonance imaging (MRI) to investigate the disintegration process of tablets containing disintegrants. A temporal resolution of 75 ms and a spatial resolution of 80 × 80 µm with a section thickness of only 600 µm were achieved. The histograms of MRI videos were quantitatively analyzed with MATLAB. The mechanisms of action of six commercially available disintegrants, the influence of relative tablet density, and the impact of disintegrant concentration were examined. Crospovidone seems to be the only disintegrant acting by a shape memory effect, whereas the others mainly swell. A higher relative density of tablets containing croscarmellose sodium leads to a more even distribution of water within the tablet matrix but hardly impacts the disintegration kinetics. Increasing the polacrilin potassium disintegrant concentration leads to a quicker and more thorough disintegration process. Real-time MRI emerges as valuable tool to visualize and investigate the process of tablet disintegration.

  15. Using very high resolution satellite images to identify coastal zone dynamics at North Western Black Sea

    Science.gov (United States)

    Florin Zoran, Liviu; Ionescu Golovanov, Carmen; Zoran, Maria

    2010-05-01

    The availability of updated information about the extension and characteristics of land cover is a crucial issue in the perspective of a correct landscape planning and management of marine coastal zones. Satellite remote sensing data can provide accurate information about land coverage at different scales and the recent availability of very high resolution images definitely improved the precision of coastal zone spatio-temporal changes. The Romanian North Western coastal and shelf zones of the Black Sea and Danube delta are a mosaic of complex, interacting ecosystems, rich natural resources and socio-economic activity. Dramatic changes in the Black Sea's ecosystem and resources are due to natural and anthropogenic causes (increase in the nutrient and pollutant load of rivers input, industrial and municipal wastewater pollution along the coast, and dumping on the open sea). A scientific management system for protection, conservation and restoration must be based on reliable information on bio-geophysical and geomorphologic processes, coastal erosion, sedimentation dynamics, mapping of macrophyte fields, water quality, and climatic change effects. Use of satellite images is of great help for coastal zone monitoring and environmental impact assessment. Synergetic use of in situ measurements with multisensors satellite data could provide a complex assessment of spatio-temporal changes. In this study was developed a method for extracting coastal zone features information as well as landcover dynamics from IKONOS, very high resolution images for North-Western Black Sea marine coastal zone. The main objective was obtaining reliable data about the spatio-temporal coastal zone changes in two study areas located in Constanta urban area and Danube Delta area. We used an object-oriented approach based on preliminary segmentation and classification of the resulting object. First of all, segmentation parameters were tested and selected comparing segmented polygons with

  16. Characterization of space-time rainfall patterns over Switzerland based on high-resolution radar images

    Science.gov (United States)

    Benoit, Lionel; Mariethoz, Gregoire; Vrac, Mathieu

    2017-04-01

    Rainfall is generated by diverse and complex processes that produce rain fields with a large variability of patterns. High-resolution measurements of rainfall, provided for instance by networks of terrestrial weather radars, allow observing the spatial variability of rainfall patterns and its temporal evolution. The characterization of these space-time rainfall patterns is important for both the understanding of rain generation processes and the study of environmental impacts of rainfall on hydrology, erosion or plants growth, among others. Here we propose to study rainfall patterns using image processing methods on high-resolution radar images (1km x 1km x 1min) over Switzerland. The time series of radar images is first segmented in rain events. Then, the spatial structure of each rain event is characterized by computing statistics over several geometrical indices extracted from radar images, by adapting to the context of mid-latitude rainfalls the indices proposed by Aghakouchak, Nasrollahi et al. (2011) and Zick and Matyas (2016) for tropical rainfall characterization. Finally, the dynamics of rainfall patterns is characterized by estimating rain advection through image correlation, and by quantifying the temporal morphing of spatial patterns in a Lagrangian reference frame, where radar images are re-projected to cancel out rain advection. Two years of data (2015 - 2016) are used to investigate the variability of rainfall patterns over Switzerland. Typical values of the indicators measuring rainfall patterns and their dynamics are extracted for different areas, namely the Jura Mountain, the Swiss Plateau and the Alps. These measures of rainfall variability could be subsequently used to parameterize local weather generators or to investigate the relationships between rainfall patterns and atmospheric synoptic conditions. References: Aghakouchak, A., N. Nasrollahi, J. Li, B. Imam and S. Sorooshian (2011). "Geometrical Characterization of Precipitation Patterns

  17. Accelerated high-resolution 3D magnetic resonance spectroscopic imaging in the brain At 7 T

    International Nuclear Information System (INIS)

    Hangel, G.

    2015-01-01

    With the announcement of the first series of magnetic resonance (MR) scanners with a field strength of 7 Tesla (T) intended for clinical practice, the development of high-performance sequences for higher field strengths has gained importance. Magnetic resonance spectroscopic imaging (MRSI) in the brain currently offers the unique ability to spatially resolve the distribution of multiple metabolites simultaneously. Its big diagnostic potential could be applied to many clinical protocols, for example the assessment of tumour treatment or progress of Multiple Sclerosis. Moving to ultra-high fields like 7 T has the main benefits of increased signal-to-noise ratio (SNR) and improved spectral quality, but brings its own challenges due to stronger field inhomogeneities. Necessary for a robust, flexible and useful MRSI sequence in the brain are high resolutions, shortened measurement times, the possibility for 3D-MRSI and the suppression of spectral contamination by trans-cranial lipids. This thesis addresses these limitations and proposes Hadamard spectroscopic imaging (HSI) as solution for multi-slice MRSI, the application of generalized autocalibrating partially parallel acquisition (GRAPPA) and spiral trajectories for measurement acceleration, non-selective inversion recovery (IR) lipid-suppression as well as combinations of these methods. Further, the optimisation of water suppression for 7 T systems and the acquisition of ultra-high resolution (UHR)-MRSI are discussed. In order to demonstrate the clinical feasibility of these approaches, MRSI measurement results of a glioma patient are presented. The discussion of the obtained results in the context of the state-of-art in 7 T MRSI in the brain, possible future applications as well as potential further improvements of the MRSI sequences conclude this thesis. (author) [de

  18. Exploring image data assimilation in the prospect of high-resolution satellite oceanic observations

    Science.gov (United States)

    Durán Moro, Marina; Brankart, Jean-Michel; Brasseur, Pierre; Verron, Jacques

    2017-07-01

    Satellite sensors increasingly provide high-resolution (HR) observations of the ocean. They supply observations of sea surface height (SSH) and of tracers of the dynamics such as sea surface salinity (SSS) and sea surface temperature (SST). In particular, the Surface Water Ocean Topography (SWOT) mission will provide measurements of the surface ocean topography at very high-resolution (HR) delivering unprecedented information on the meso-scale and submeso-scale dynamics. This study investigates the feasibility to use these measurements to reconstruct meso-scale features simulated by numerical models, in particular on the vertical dimension. A methodology to reconstruct three-dimensional (3D) multivariate meso-scale scenes is developed by using a HR numerical model of the Solomon Sea region. An inverse problem is defined in the framework of a twin experiment where synthetic observations are used. A true state is chosen among the 3D multivariate states which is considered as a reference state. In order to correct a first guess of this true state, a two-step analysis is carried out. A probability distribution of the first guess is defined and updated at each step of the analysis: (i) the first step applies the analysis scheme of a reduced-order Kalman filter to update the first guess probability distribution using SSH observation; (ii) the second step minimizes a cost function using observations of HR image structure and a new probability distribution is estimated. The analysis is extended to the vertical dimension using 3D multivariate empirical orthogonal functions (EOFs) and the probabilistic approach allows the update of the probability distribution through the two-step analysis. Experiments show that the proposed technique succeeds in correcting a multivariate state using meso-scale and submeso-scale information contained in HR SSH and image structure observations. It also demonstrates how the surface information can be used to reconstruct the ocean state below

  19. Learning Low Dimensional Convolutional Neural Networks for High-Resolution Remote Sensing Image Retrieval

    Directory of Open Access Journals (Sweden)

    Weixun Zhou

    2017-05-01

    Full Text Available Learning powerful feature representations for image retrieval has always been a challenging task in the field of remote sensing. Traditional methods focus on extracting low-level hand-crafted features which are not only time-consuming but also tend to achieve unsatisfactory performance due to the complexity of remote sensing images. In this paper, we investigate how to extract deep feature representations based on convolutional neural networks (CNNs for high-resolution remote sensing image retrieval (HRRSIR. To this end, several effective schemes are proposed to generate powerful feature representations for HRRSIR. In the first scheme, a CNN pre-trained on a different problem is treated as a feature extractor since there are no sufficiently-sized remote sensing datasets to train a CNN from scratch. In the second scheme, we investigate learning features that are specific to our problem by first fine-tuning the pre-trained CNN on a remote sensing dataset and then proposing a novel CNN architecture based on convolutional layers and a three-layer perceptron. The novel CNN has fewer parameters than the pre-trained and fine-tuned CNNs and can learn low dimensional features from limited labelled images. The schemes are evaluated on several challenging, publicly available datasets. The results indicate that the proposed schemes, particularly the novel CNN, achieve state-of-the-art performance.

  20. Classification of high resolution satellite images using spatial constraints-based fuzzy clustering

    Science.gov (United States)

    Singh, Pankaj Pratap; Garg, Rahul Dev

    2014-01-01

    A spatial constraints-based fuzzy clustering technique is introduced in the paper and the target application is classification of high resolution multispectral satellite images. This fuzzy-C-means (FCM) technique enhances the classification results with the help of a weighted membership function (Wmf). Initially, spatial fuzzy clustering (FC) is used to segment the targeted vegetation areas with the surrounding low vegetation areas, which include the information of spatial constraints (SCs). The performance of the FCM image segmentation is subject to appropriate initialization of Wmf and SC. It is able to evolve directly from the initial segmentation by spatial fuzzy clustering. The controlling parameters in fuzziness of the FCM approach, Wmf and SC, help to estimate the segmented road results, then the Stentiford thinning algorithm is used to estimate the road network from the classified results. Such improvements facilitate FCM method manipulation and lead to segmentation that is more robust. The results confirm its effectiveness for satellite image classification, which extracts useful information in suburban and urban areas. The proposed approach, spatial constraint-based fuzzy clustering with a weighted membership function (SCFCWmf), has been used to extract the information of healthy trees with vegetation and shadows showing elevated features in satellite images. The performance values of quality assessment parameters show a good degree of accuracy for segmented roads using the proposed hybrid SCFCWmf-MO (morphological operations) approach which also occluded nonroad parts.

  1. A New Approach to Urban Road Extraction Using High-Resolution Aerial Image

    Directory of Open Access Journals (Sweden)

    Jianhua Wang

    2016-07-01

    Full Text Available Road information is fundamental not only in the military field but also common daily living. Automatic road extraction from a remote sensing images can provide references for city planning as well as transportation database and map updating. However, owing to the spectral similarity between roads and impervious structures, the current methods solely using spectral characteristics are often ineffective. By contrast, the detailed information discernible from the high-resolution aerial images enables road extraction with spatial texture features. In this study, a knowledge-based method is established and proposed; this method incorporates the spatial texture feature into urban road extraction. The spatial texture feature is initially extracted by the local Moran’s I, and the derived texture is added to the spectral bands of image for image segmentation. Subsequently, features like brightness, standard deviation, rectangularity, aspect ratio, and area are selected to form the hypothesis and verification model based on road knowledge. Finally, roads are extracted by applying the hypothesis and verification model and are post-processed based on the mathematical morphology. The newly proposed method is evaluated by conducting two experiments. Results show that the completeness, correctness, and quality of the results could reach approximately 94%, 90% and 86% respectively, indicating that the proposed method is effective for urban road extraction.

  2. OBJECTS GROUPING FOR SEGMENTATION OF ROADS NETWORK IN HIGH RESOLUTION IMAGES OF URBAN AREAS

    Directory of Open Access Journals (Sweden)

    M. Maboudi

    2016-06-01

    Full Text Available Updated road databases are required for many purposes such as urban planning, disaster management, car navigation, route planning, traffic management and emergency handling. In the last decade, the improvement in spatial resolution of VHR civilian satellite sensors – as the main source of large scale mapping applications – was so considerable that GSD has become finer than size of common urban objects of interest such as building, trees and road parts. This technological advancement pushed the development of “Object-based Image Analysis (OBIA” as an alternative to pixel-based image analysis methods. Segmentation as one of the main stages of OBIA provides the image objects on which most of the following processes will be applied. Therefore, the success of an OBIA approach is strongly affected by the segmentation quality. In this paper, we propose a purpose-dependent refinement strategy in order to group road segments in urban areas using maximal similarity based region merging. For investigations with the proposed method, we use high resolution images of some urban sites. The promising results suggest that the proposed approach is applicable in grouping of road segments in urban areas.

  3. High Resolution Fluorescence Imaging of Cancers Using Lanthanide Ion-Doped Upconverting Nanocrystals

    Directory of Open Access Journals (Sweden)

    John A. Capobianco

    2012-10-01

    Full Text Available During the last decade inorganic luminescent nanoparticles that emit visible light under near infrared (NIR excitation (in the biological window have played a relevant role for high resolution imaging of cancer. Indeed, semiconductor quantum dots (QDs and metal nanoparticles, mostly gold nanorods (GNRs, are already commercially available for this purpose. In this work we review the role which is being played by a relatively new class of nanoparticles, based on lanthanide ion doped nanocrystals, to target and image cancer cells using upconversion fluorescence microscopy. These nanoparticles are insulating nanocrystals that are usually doped with small percentages of two different rare earth (lanthanide ions: The excited donor ions (usually Yb3+ ion that absorb the NIR excitation and the acceptor ions (usually Er3+, Ho3+ or Tm3+, that are responsible for the emitted visible (or also near infrared radiation. The higher conversion efficiency of these nanoparticles in respect to those based on QDs and GNRs, as well as the almost independent excitation/emission properties from the particle size, make them particularly promising for fluorescence imaging. The different approaches of these novel nanoparticles devoted to "in vitro" and "in vivo" cancer imaging, selective targeting and treatment are examined in this review.

  4. Imaging of aortopulmonary collateral arteries with high-resolution multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Greil, Gerald F.; Hofbeck, Michael; Sieverding, Ludger [University of Tuebingen, Department of Pediatric Cardiology, Children' s Hospital, Tuebingen (Germany); Schoebinger, Max; Meinzer, Hans-Peter [German Cancer Research Center, Division of Medical and Biological Informatics, Heidelberg (Germany); Kuettner, Axel; Schaefer, Juergen F.; Dammann, Florian; Claussen, Claus D. [University of Tuebingen, Department of Diagnostic Radiology, Tuebingen (Germany)

    2006-06-15

    Precise visualization of the pulmonary vasculature is mandatory for adequate treatment of patients with pulmonary atresia and ventricular septal defect (PA-VSD). Aortopulmonary collateral arteries (APCs) can be visualized by selective injections of contrast agent in the catheterization laboratory. To evaluate multidetector CT (MDCT) and different image postprocessing methods for analysis of complex pulmonary blood supply in patients with PA-VSD. Eight patients (6 weeks to 27.8 years of age) with PA-VSD and APCs underwent MDCT and cardiac catheterization. Using multiplanar reformatting, volume rendering and semiautomatic segmentation algorithms, the aorta, pulmonary arteries and APCs were displayed. MDCT and cardiac catheterization were analyzed by two independent observers. MDCT accurately imaged central pulmonary arteries (n=8), aortopulmonary shunts (n=2), right ventricular to pulmonary artery conduits (n=2) and origin, course and intrapulmonary connections of APCs (n=25), compared to X-ray angiography. A high correlation was found between the MDCT vessel diameter measurements by two independent observers (n=70, r=0.96, P<0.01) and between MDCT and angiographic vessel diameter measurements (n=68, r=0.96, P<0.01). Using three-dimensional imaging software, a complex pulmonary blood supply can be non-invasively and accurately imaged with high-resolution MDCT. This technique may help to reduce the number of cardiac catheterizations or guide interventional or surgical therapy. (orig.)

  5. AUTOMATED DETECTION OF OIL DEPOTS FROM HIGH RESOLUTION IMAGES: A NEW PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    A. O. Ok

    2015-03-01

    Full Text Available This paper presents an original approach to identify oil depots from single high resolution aerial/satellite images in an automated manner. The new approach considers the symmetric nature of circular oil depots, and it computes the radial symmetry in a unique way. An automated thresholding method to focus on circular regions and a new measure to verify circles are proposed. Experiments are performed on six GeoEye-1 test images. Besides, we perform tests on 16 Google Earth images of an industrial test site acquired in a time series manner (between the years 1995 and 2012. The results reveal that our approach is capable of detecting circle objects in very different/difficult images. We computed an overall performance of 95.8% for the GeoEye-1 dataset. The time series investigation reveals that our approach is robust enough to locate oil depots in industrial environments under varying illumination and environmental conditions. The overall performance is computed as 89.4% for the Google Earth dataset, and this result secures the success of our approach compared to a state-of-the-art approach.

  6. High Resolution Fluorescence Imaging of Cancers Using Lanthanide Ion-Doped Upconverting Nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Naccache, Rafik; Rodríguez, Emma Martín; Bogdan, Nicoleta [Department of Chemistry and Biochemistry, Concordia University, Montreal H4B 1R6 (Canada); Sanz-Rodríguez, Francisco [Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid 28049 (Spain); Cruz, Maria del Carmen Iglesias de la [Departamento de Fisiología. Facultad de Medicina, Universidad Autónoma de Madrid, Madrid 28029 (Spain); Fuente, Ángeles Juarranz de la [Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid 28049 (Spain); Vetrone, Fiorenzo [Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, Université du Québec, Varennes J3X 1S2 (Canada); Jaque, Daniel; Solé, José García, E-mail: jose.garcia_sole@uam.es [Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid 28049 (Spain); Capobianco, John A., E-mail: jose.garcia_sole@uam.es [Department of Chemistry and Biochemistry, Concordia University, Montreal H4B 1R6 (Canada)

    2012-10-22

    During the last decade inorganic luminescent nanoparticles that emit visible light under near infrared (NIR) excitation (in the biological window) have played a relevant role for high resolution imaging of cancer. Indeed, semiconductor quantum dots (QDs) and metal nanoparticles, mostly gold nanorods (GNRs), are already commercially available for this purpose. In this work we review the role which is being played by a relatively new class of nanoparticles, based on lanthanide ion doped nanocrystals, to target and image cancer cells using upconversion fluorescence microscopy. These nanoparticles are insulating nanocrystals that are usually doped with small percentages of two different rare earth (lanthanide) ions: The excited donor ions (usually Yb{sup 3+} ion) that absorb the NIR excitation and the acceptor ions (usually Er{sup 3+}, Ho{sup 3+} or Tm{sup 3+}), that are responsible for the emitted visible (or also near infrared) radiation. The higher conversion efficiency of these nanoparticles in respect to those based on QDs and GNRs, as well as the almost independent excitation/emission properties from the particle size, make them particularly promising for fluorescence imaging. The different approaches of these novel nanoparticles devoted to “in vitro” and “in vivo” cancer imaging, selective targeting and treatment are examined in this review.

  7. Computationally-optimized bone mechanical modeling from high-resolution structural images.

    Directory of Open Access Journals (Sweden)

    Jeremy F Magland

    Full Text Available Image-based mechanical modeling of the complex micro-structure of human bone has shown promise as a non-invasive method for characterizing bone strength and fracture risk in vivo. In particular, elastic moduli obtained from image-derived micro-finite element (μFE simulations have been shown to correlate well with results obtained by mechanical testing of cadaveric bone. However, most existing large-scale finite-element simulation programs require significant computing resources, which hamper their use in common laboratory and clinical environments. In this work, we theoretically derive and computationally evaluate the resources needed to perform such simulations (in terms of computer memory and computation time, which are dependent on the number of finite elements in the image-derived bone model. A detailed description of our approach is provided, which is specifically optimized for μFE modeling of the complex three-dimensional architecture of trabecular bone. Our implementation includes domain decomposition for parallel computing, a novel stopping criterion, and a system for speeding up convergence by pre-iterating on coarser grids. The performance of the system is demonstrated on a dual quad-core Xeon 3.16 GHz CPUs equipped with 40 GB of RAM. Models of distal tibia derived from 3D in-vivo MR images in a patient comprising 200,000 elements required less than 30 seconds to converge (and 40 MB RAM. To illustrate the system's potential for large-scale μFE simulations, axial stiffness was estimated from high-resolution micro-CT images of a voxel array of 90 million elements comprising the human proximal femur in seven hours CPU time. In conclusion, the system described should enable image-based finite-element bone simulations in practical computation times on high-end desktop computers with applications to laboratory studies and clinical imaging.

  8. High resolution X-ray fluorescence imaging for a microbeam radiation therapy treatment planning system

    Science.gov (United States)

    Chtcheprov, Pavel; Inscoe, Christina; Burk, Laurel; Ger, Rachel; Yuan, Hong; Lu, Jianping; Chang, Sha; Zhou, Otto

    2014-03-01

    Microbeam radiation therapy (MRT) uses an array of high-dose, narrow (~100 μm) beams separated by a fraction of a millimeter to treat various radio-resistant, deep-seated tumors. MRT has been shown to spare normal tissue up to 1000 Gy of entrance dose while still being highly tumoricidal. Current methods of tumor localization for our MRT treatments require MRI and X-ray imaging with subject motion and image registration that contribute to the measurement error. The purpose of this study is to develop a novel form of imaging to quickly and accurately assist in high resolution target positioning for MRT treatments using X-ray fluorescence (XRF). The key to this method is using the microbeam to both treat and image. High Z contrast media is injected into the phantom or blood pool of the subject prior to imaging. Using a collimated spectrum analyzer, the region of interest is scanned through the MRT beam and the fluorescence signal is recorded for each slice. The signal can be processed to show vascular differences in the tissue and isolate tumor regions. Using the radiation therapy source as the imaging source, repositioning and registration errors are eliminated. A phantom study showed that a spatial resolution of a fraction of microbeam width can be achieved by precision translation of the mouse stage. Preliminary results from an animal study showed accurate iodine profusion, confirmed by CT. The proposed image guidance method, using XRF to locate and ablate tumors, can be used as a fast and accurate MRT treatment planning system.

  9. Design and development of a high resolution animal SPECT scanner dedicated for rat and mouse imaging

    International Nuclear Information System (INIS)

    Sajedi, Salar; Zeraatkar, Navid; Moji, Vahideh; Farahani, Mohammad Hossein; Sarkar, Saeed; Arabi, Hossein; Teymoorian, Behnoosh; Ghafarian, Pardis; Rahmim, Arman; Reza Ay, Mohammad

    2014-01-01

    A dedicated small-animal SPECT system, HiReSPECT, was designed and developed to provide a high resolution molecular imaging modality in response to growing research demands. HiReSPECT is a dual-head system mounted on a rotating gantry. The detection system is based on pixelated CsI(Na) scintillator crystals coupled to two Hamamatsu H8500 Position Sensitive Photomultiplier Tubes in each head. Also, a high resolution parallel-hole collimator is applied to every head. The dimensions of each head are 50 mm×100 mm, enabling sufficient transaxial and axial fields-of-view (TFOV and AFOV), respectively, for coverage of the entire mouse in single-bed position imaging. However, a 50 mm TFOV is not sufficient for transaxial coverage of rats. To address this, each head can be rotated by 90 degrees in order to align the larger dimension of the heads with the short body axis, allowing tomographic data acquisition for rats. An innovative non-linear recursive filter was used for signal processing/detection. Resolution recovery was also embedded in the modified Maximum-Likelihood Expectation Maximization (MLEM) image reconstruction code to compensate for Collimator-Detector Response (CDR). Moreover, an innovative interpolation algorithm was developed to speed up the reconstruction code. The planar spatial resolution at the head surface and the image spatial resolutions were 1.7 mm and 1.2–1.6 mm, respectively. The measurements followed by post-processing showed that the observed count rate at 20% count loss is about 42 kcps. The system sensitivity at the collimator surface for heads 1 and 2 were 1.32 cps/µCi and 1.25 cps/µCi, respectively. The corresponding values were 1.18 cps/µCi and 1.02 cps/µCi at 8 cm distance from the collimator surfaces. In addition, whole-body scans of mice demonstrated appropriate imaging capability of the HiReSPECT

  10. High-resolution light-scattering imaging with two-dimensional hexagonal illumination patterns: system implementation and image reconstruction formulations.

    Science.gov (United States)

    Chen, Chih-Wei; Wang, Po-Hsun; Chou, Li-Jun; Lee, Yin-Yu; Chang, Bo-Jui; Chiang, Su-Yu

    2017-09-04

    Structured illumination microscopy (SIM) was recently adapted to coherent imaging, named structured oblique-illumination microscopy (SOIM), to improve the contrast and resolution of a light-scattering image. Herein, we present high-resolution laterally isotropic SOIM imaging with 2D hexagonal illuminations. The SOIM is implemented in a SIM fluorescence system based on a spatial-light modulator (SLM). We design an SLM pattern to generate diffraction beams at 0° and ± 60.3° simultaneously to form a 2D hexagonal illumination, and undertake calculations to obtain optimal SLM shifts at 19 phases to yield a reconstructed image correctly. Beams of linear and circular polarizations are used to show the effect of polarization on the resolution improvement. We derive the distributions of the electric field of the resultant hexagonal patterns and work out the formulations of the corresponding coherent-scattering imaging for image reconstruction. The reconstructed images of gold nanoparticles (100 nm) confirm the two-fold improvement of resolution and reveal the effect of polarization on resolving adjacent nanoparticles. To demonstrate biological applications, we present the cellular structures of a label-free fixed HeLa cell with improved contrast and resolution. This work enables one to perform high-resolution dual-mode - fluorescence and light-scattering - imaging in a system, and is expected to broaden the applications of SOIM.

  11. High Resolution/High Fidelity Seismic Imaging and Parameter Estimation for Geological Structure and Material Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Ru-Shan Wu; Xiao-Bi Xie

    2008-06-08

    Our proposed work on high resolution/high fidelity seismic imaging focused on three general areas: (1) development of new, more efficient, wave-equation-based propagators and imaging conditions, (2) developments towards amplitude-preserving imaging in the local angle domain, in particular, imaging methods that allow us to estimate the reflection as a function of angle at a layer boundary, and (3) studies of wave inversion for local parameter estimation. In this report we summarize the results and progress we made during the project period. The report is divided into three parts, totaling 10 chapters. The first part is on resolution analysis and its relation to directional illumination analysis. The second part, which is composed of 6 chapters, is on the main theme of our work, the true-reflection imaging. True-reflection imaging is an advanced imaging technology which aims at keeping the image amplitude proportional to the reflection strength of the local reflectors or to obtain the reflection coefficient as function of reflection-angle. There are many factors which may influence the image amplitude, such as geometrical spreading, transmission loss, path absorption, acquisition aperture effect, etc. However, we can group these into two categories: one is the propagator effect (geometric spreading, path losses); the other is the acquisition-aperture effect. We have made significant progress in both categories. We studied the effects of different terms in the true-amplitude one-way propagators, especially the terms including lateral velocity variation of the medium. We also demonstrate the improvements by optimizing the expansion coefficients in different terms. Our research also includes directional illumination analysis for both the one-way propagators and full-wave propagators. We developed the fast acquisition-aperture correction method in the local angle-domain, which is an important element in the true-reflection imaging. Other developments include the super

  12. High resolution hemodynamic profiling of murine arteriovenous fistula using magnetic resonance imaging and computational fluid dynamics.

    Science.gov (United States)

    Pike, Daniel; Shiu, Yan-Ting; Somarathna, Maheshika; Guo, Lingling; Isayeva, Tatyana; Totenhagen, John; Lee, Timmy

    2017-03-20

    Arteriovenous fistula (AVF) maturation failure remains a major cause of morbidity and mortality in hemodialysis patients. The two major etiologies of AVF maturation failure are early neointimal hyperplasia development and persistent inadequate outward remodeling. Although hemodynamic changes following AVF creation may impact AVF remodeling and contribute to neointimal hyperplasia development and impaired outward remodeling, detailed AVF hemodynamics are not yet fully known. Since murine AVF models are valuable tools for investigating the pathophysiology of AVF maturation failure, there is a need for a new approach that allows the hemodynamic characterization of murine AVF at high resolutions. This methods paper presents a magnetic resonance imaging (MRI)-based computational fluid dynamic (CFD) method that we developed to rigorously quantify the evolving hemodynamic environment in murine AVF. The lumen geometry of the entire murine AVF was reconstructed from high resolution, non-contrast 2D T2-weighted fast spin echo MRI sequence, and the flow rates of the AVF inflow and outflow were extracted from a gradient echo velocity mapping sequence. Using these MRI-obtained lumen geometry and inflow information, CFD modeling was performed and used to calculate blood flow velocity and hemodynamic factors at high resolutions (on the order of 0.5 μm spatially and 0.1 ms temporally) throughout the entire AVF lumen. We investigated both the wall properties (including wall shear stress (WSS), wall shear stress spatial gradient, and oscillatory shear index (OSI)) and the volumetric properties (including vorticity, helicity, and Q-criterion). Our results demonstrate increases in AVF flow velocity, WSS, spatial WSS gradient, and OSI within 3 weeks post-AVF creation when compared to pre-surgery. We also observed post-operative increases in flow disturbances and vortices, as indicated by increased vorticity, helicity, and Q-criterion. This novel protocol will enable us to undertake

  13. Atomic force microscopy: High resolution dynamic imaging of cellular and molecular structure in health and disease.

    Science.gov (United States)

    Taatjes, Douglas J; Quinn, Anthony S; Rand, Jacob H; Jena, Bhanu P

    2013-10-01

    The atomic force microscope (AFM), invented in 1986, and a member of the scanning probe family of microscopes, offers the unprecedented ability to image biological samples unfixed and in a hydrated environment at high resolution. This opens the possibility to investigate biological mechanisms temporally in a heretofore unattainable resolution. We have used AFM to investigate: (1) fundamental issues in cell biology (secretion) and, (2) the pathological basis of a human thrombotic disease, the antiphospholipid syndrome (APS). These studies have incorporated the imaging of live cells at nanometer resolution, leading to discovery of the "porosome," the universal secretory portal in cells, and a molecular understanding of membrane fusion from imaging the interaction and assembly of proteins between opposing lipid membranes. Similarly, the development of an in vitro simulacrum for investigating the molecular interactions between proteins and lipids has helped define an etiological explanation for APS. The prime importance of AFM in the success of these investigations will be presented in this manuscript, as well as a discussion of the limitations of this technique for the study of biomedical samples. Copyright © 2013 Wiley Periodicals, Inc.

  14. High resolution mapping of urban areas using SPOT-5 images and ancillary data

    Directory of Open Access Journals (Sweden)

    Elif Sertel

    2015-08-01

    Full Text Available This research aims to propose new rule sets to be used for object based classification of SPOT-5 images to accurately create detailed urban land cover/use maps. In addition to SPOT-5 satellite images, Normalized Difference Vegetation Index (NDVI and Normalized Difference Water Index (NDWI maps, cadastral maps, Openstreet maps, road maps and Land Cover maps, were also integrated into classification to increase the accuracy of resulting maps. Gaziantep city, one of the highly populated cities of Turkey with different landscape patterns was selected as the study area. Different rule sets involving spectral, spatial and geometric characteristics were developed to be used for object based classification of 2.5 m resolution Spot-5 satellite images to automatically create urban map of the region. Twenty different land cover/use classes obtained from European Urban Atlas project were applied and an automatic classification approach was suggested for high resolution urban map creation and updating. Integration of different types of data into the classification decision tree increased the performance and accuracy of the suggested approach. The accuracy assessment results illustrated that with the usage of newly proposed rule set algorithms in object-based classification, urban areas represented with seventeen different sub-classes could be mapped with 94 % or higher overall accuracy.

  15. A research of road centerline extraction algorithm from high resolution remote sensing images

    Science.gov (United States)

    Zhang, Yushan; Xu, Tingfa

    2017-09-01

    Satellite remote sensing technology has become one of the most effective methods for land surface monitoring in recent years, due to its advantages such as short period, large scale and rich information. Meanwhile, road extraction is an important field in the applications of high resolution remote sensing images. An intelligent and automatic road extraction algorithm with high precision has great significance for transportation, road network updating and urban planning. The fuzzy c-means (FCM) clustering segmentation algorithms have been used in road extraction, but the traditional algorithms did not consider spatial information. An improved fuzzy C-means clustering algorithm combined with spatial information (SFCM) is proposed in this paper, which is proved to be effective for noisy image segmentation. Firstly, the image is segmented using the SFCM. Secondly, the segmentation result is processed by mathematical morphology to remover the joint region. Thirdly, the road centerlines are extracted by morphology thinning and burr trimming. The average integrity of the centerline extraction algorithm is 97.98%, the average accuracy is 95.36% and the average quality is 93.59%. Experimental results show that the proposed method in this paper is effective for road centerline extraction.

  16. Is your system calibrated? MRI gradient system calibration for pre-clinical, high-resolution imaging.

    Directory of Open Access Journals (Sweden)

    James O'Callaghan

    Full Text Available High-field, pre-clinical MRI systems are widely used to characterise tissue structure and volume in small animals, using high resolution imaging. Both applications rely heavily on the consistent, accurate calibration of imaging gradients, yet such calibrations are typically only performed during maintenance sessions by equipment manufacturers, and potentially with acceptance limits that are inadequate for phenotyping. To overcome this difficulty, we present a protocol for gradient calibration quality assurance testing, based on a 3D-printed, open source, structural phantom that can be customised to the dimensions of individual scanners and RF coils. In trials on a 9.4 T system, the gradient scaling errors were reduced by an order of magnitude, and displacements of greater than 100 µm, caused by gradient non-linearity, were corrected using a post-processing technique. The step-by-step protocol can be integrated into routine pre-clinical MRI quality assurance to measure and correct for these errors. We suggest that this type of quality assurance is essential for robust pre-clinical MRI experiments that rely on accurate imaging gradients, including small animal phenotyping and diffusion MR.

  17. HIGH RESOLUTION AIRBORNE LASER SCANNING AND HYPERSPECTRAL IMAGING WITH A SMALL UAV PLATFORM

    Directory of Open Access Journals (Sweden)

    M. Gallay

    2016-06-01

    Full Text Available The capabilities of unmanned airborne systems (UAS have become diverse with the recent development of lightweight remote sensing instruments. In this paper, we demonstrate our custom integration of the state-of-the-art technologies within an unmanned aerial platform capable of high-resolution and high-accuracy laser scanning, hyperspectral imaging, and photographic imaging. The technological solution comprises the latest development of a completely autonomous, unmanned helicopter by Aeroscout, the Scout B1-100 UAV helicopter. The helicopter is powered by a gasoline two-stroke engine and it allows for integrating 18 kg of a customized payload unit. The whole system is modular providing flexibility of payload options, which comprises the main advantage of the UAS. The UAS integrates two kinds of payloads which can be altered. Both payloads integrate a GPS/IMU with a dual GPS antenna configuration provided by OXTS for accurate navigation and position measurements during the data acquisition. The first payload comprises a VUX-1 laser scanner by RIEGL and a Sony A6000 E-Mount photo camera. The second payload for hyperspectral scanning integrates a push-broom imager AISA KESTREL 10 by SPECIM. The UAS was designed for research of various aspects of landscape dynamics (landslides, erosion, flooding, or phenology in high spectral and spatial resolution.

  18. AN ADAPTIVE MORPHOLOGICAL MEAN FILTER FOR VERY HIGH-RESOLUTION REMOTE SENSING IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    Z. Lv

    2017-09-01

    Full Text Available Very high resolution (VHR remote sensing imagery can reveal the ground object in greater detail, depicting their color, shape, size and structure. However, VHR also leads much original noise in spectra, and this original noise may reduce the reliability of the classification’s result. This paper presents an Adaptive Morphological Mean Filter (AMMF for smoothing the original noise of VHR imagery and improving the classification’s performance. AMMF is a shape-adaptive filter which is constructed by detecting gradually the spectral similarity between a kernel-anchored pixel and its contextual pixels through an extension-detector with 8-neighbouring pixels, and the spectral value of the kernel-anchored pixel is instead by the mean of group pixels within the adaptive region. The classification maps based on the AMMF are compared with the classification of VHR images based on the homologous filter processing, such as Mean Filter (MF and Median Filter(MedF. The experimental results suggest the following: 1 VHR image processed using AMMF can not only preserve the detail information among inter-classes but also smooth the noise within intra-class; 2 The proposed AMMF processing can improve the classification’s performance of VHR image, and it obtains a better visual performance and accuracy while comparing with MF and MedF.

  19. Comet Shoemaker-Levy 9/Jupiter collision observed with a high resolution speckle imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Gravel, D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    During the week of July 16, 1994, comet Shoemaker-Levy 9, broken into 20 plus pieces by tidal forces on its last orbit, smashed into the planet Jupiter, releasing the explosive energy of 500 thousand megatons. A team of observers from LLNL used the LLNL Speckle Imaging Camera mounted on the University of California`s Lick Observatory 3 Meter Telescope to capture continuous sequences of planet images during the comet encounter. Post processing with the bispectral phase reconstruction algorithm improves the resolution by removing much of the blurring due to atmospheric turbulence. High resolution images of the planet surface showing the aftermath of the impact are probably the best that were obtained from any ground-based telescope. We have been looking at the regions of the fragment impacts to try to discern any dynamic behavior of the spots left on Jupiter`s cloud tops. Such information can lead to conclusions about the nature of the comet and of Jupiter`s atmosphere. So far, the Hubble Space Telescope has observed expanding waves from the G impact whose mechanism is enigmatic since they appear to be too slow to be sound waves and too fast to be gravity waves, given the present knowledge of Jupiter`s atmosphere. Some of our data on the G and L impact region complements the Hubble observations but, so far, is inconclusive about spot dynamics.

  20. Graphene Nanopore Support System for Simultaneous High-Resolution AFM Imaging and Conductance Measurements

    Science.gov (United States)

    2015-01-01

    Accurately defining the nanoporous structure and sensing the ionic flow across nanoscale pores in thin films and membranes has a wide range of applications, including characterization of biological ion channels and receptors, DNA sequencing, molecule separation by nanoparticle films, sensing by block co-polymers films, and catalysis through metal–organic frameworks. Ionic conductance through nanopores is often regulated by their 3D structures, a relationship that can be accurately determined only by their simultaneous measurements. However, defining their structure–function relationships directly by any existing techniques is still not possible. Atomic force microscopy (AFM) can image the structures of these pores at high resolution in an aqueous environment, and electrophysiological techniques can measure ion flow through individual nanoscale pores. Combining these techniques is limited by the lack of nanoscale interfaces. We have designed a graphene-based single-nanopore support (∼5 nm thick with ∼20 nm pore diameter) and have integrated AFM imaging and ionic conductance recording using our newly designed double-chamber recording system to study an overlaid thin film. The functionality of this integrated system is demonstrated by electrical recording (nanopore and simultaneous AFM imaging of the bilayer. PMID:24581087

  1. Rule-based land cover classification from very high-resolution satellite image with multiresolution segmentation

    Science.gov (United States)

    Haque, Md. Enamul; Al-Ramadan, Baqer; Johnson, Brian A.

    2016-07-01

    Multiresolution segmentation and rule-based classification techniques are used to classify objects from very high-resolution satellite images of urban areas. Custom rules are developed using different spectral, geometric, and textural features with five scale parameters, which exploit varying classification accuracy. Principal component analysis is used to select the most important features out of a total of 207 different features. In particular, seven different object types are considered for classification. The overall classification accuracy achieved for the rule-based method is 95.55% and 98.95% for seven and five classes, respectively. Other classifiers that are not using rules perform at 84.17% and 97.3% accuracy for seven and five classes, respectively. The results exploit coarse segmentation for higher scale parameter and fine segmentation for lower scale parameter. The major contribution of this research is the development of rule sets and the identification of major features for satellite image classification where the rule sets are transferable and the parameters are tunable for different types of imagery. Additionally, the individual objectwise classification and principal component analysis help to identify the required object from an arbitrary number of objects within images given ground truth data for the training.

  2. High resolution radio imaging study of the Pulsar Wind Nebula MSH 15-52

    Science.gov (United States)

    Leung, W.-Y.; Ng, C.-Y.

    2016-06-01

    We present a new high-resolution radio imaging study of the pulsar wind nebula (PWN) MSH 15-52, also dubbed as "the hand of God", with the Australia Telescope Compact Array observations. The system is powered by a young and energetic radio pulsar B1509-58 with high spin down luminosity of E(dot) = 2 x 10^37 erg/s. Previous X-ray images have shown that the PWN has a complex hand-shape morphology extending over 10 pc with features like jets, arc, filaments and enhanced emission knots in the HII region RCW 89. The new 6cm and 3cm radio images show different morphology than the X-ray counterpart. No radio counterpart of the X-ray jet is detected, instead we found enhanced emission in a sheath surrounding the jet. Additional small-scale features including a polarized linear filament next to the pulsar have also been discovered. Our polarisation measurements show that the intrinsic orientation of magnetic field aligns with the sheath. Finally, spectral analysis results indicate a steep spectrum for the system, which is rather unusual among PWNe. Implications of these findings will be discussed. The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. This work is supported by an ECS grant under HKU 709713P.

  3. Results of high resolution seismic imaging experiments for defining permeable pathways in fractured gas reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Majer, E.L.; Peterson, J.E.; Daley, T. [and others

    1997-10-01

    As part of its Department of Energy (DOE) Industry cooperative program in oil and gas, Berkeley Lab has an ongoing effort in cooperation with Industry partners to develop equipment, field techniques, and interpretational methods to further the practice of characterizing fractured heterogeneous reservoirs. The goal of this work is to demonstrate the combined use of state-of-the-art technology in fluid flow modeling and geophysical imaging into an interdisciplinary approach for predicting the behavior of heterogeneous fractured gas reservoirs. The efforts in this program have mainly focused on using seismic methods linked with geologic and reservoir engineering analysis for the detection and characterization of fracture systems in tight gas formations, i.e., where and how to detect the fractures, what are the characteristics of the fractures, and how the fractures interact with the natural stresses, lithology, and their effect on reservoir performance. The project has also integrated advanced reservoir engineering methods for analyzing flow in fractured systems such that reservoir management strategies can be optimized. The work at Berkeley Lab focuses on integrating high resolution seismic imaging, (VSP, crosswell, and single well imaging), geologic information and well test data to invert for flow paths in fractured systems.

  4. Structural anomalies in undoped Gallium Arsenide observed in high resolution diffraction imaging with monochromatic synchrotron radiation

    Science.gov (United States)

    Steiner, B.; Kuriyama, M.; Dobbyn, R. C.; Laor, U.; Larson, D.; Brown, M.

    1988-01-01

    Novel, streak-like disruption features restricted to the plane of diffraction have recently been observed in images obtained by synchrotron radiation diffraction from undoped, semi-insulating gallium arsenide crystals. These features were identified as ensembles of very thin platelets or interfaces lying in (110) planes, and a structural model consisting of antiphase domain boundaries was proposed. We report here the other principal features observed in high resolution monochromatic synchrotron radiation diffraction images: (quasi) cellular structure; linear, very low-angle subgrain boundaries in (110) directions, and surface stripes in a (110) direction. In addition, we report systematic differences in the acceptance angle for images involving various diffraction vectors. When these observations are considered together, a unifying picture emerges. The presence of ensembles of thin (110) antiphase platelet regions or boundaries is generally consistent not only with the streak-like diffraction features but with the other features reported here as well. For the formation of such regions we propose two mechanisms, operating in parallel, that appear to be consistent with the various defect features observed by a variety of techniques.

  5. NITESat: A High Resolution, Full-Color, Light Pollution Imaging Satellite Mission

    Directory of Open Access Journals (Sweden)

    Ken Walczak

    2017-06-01

    Full Text Available The NITESat (Night Imaging and Tracking Experiment Satellite mission is a 2U CubeSat satellite designed for nighttime Earth imaging to quantify and characterize light pollution across the Midwestern United States. It is accompanied and supported by an array of ground-based light pollution observing stations called GONet (Ground Observing Network. NITESat is a pilot mission testing the potential for a simple and inexpensive (<$500,000 satellite to deliver high-resolution, three-color regional data of artificial light at night. In addition, GONet will form the core of an educational outreach program by establishing an array of all-sky monitors covering the imaging region of the satellite with 20+ full sky light pollution citizen-operated stations. This will provide synchronized data coinciding with the NITESat overpasses as well as providing near continuous night sky quality monitoring. If the initial mission is a success, the potential exists to expand the program into a low cost constellation of satellites capable of delivering global coverage. NITESat is being designed, built and will be operated by the Far Horizons program at the Adler Planetarium in Chicago, Illinois. Far Horizons is a student and volunteer centered program offering hands-on engineering and scientific research opportunities for education.

  6. S-Cnn Ship Detection from High-Resolution Remote Sensing Images

    Science.gov (United States)

    Zhang, Ruiqian; Yao, Jian; Zhang, Kao; Feng, Chen; Zhang, Jiadong

    2016-06-01

    Reliable ship detection plays an important role in both military and civil fields. However, it makes the task difficult with high-resolution remote sensing images with complex background and various types of ships with different poses, shapes and scales. Related works mostly used gray and shape features to detect ships, which obtain results with poor robustness and efficiency. To detect ships more automatically and robustly, we propose a novel ship detection method based on the convolutional neural networks (CNNs), called SCNN, fed with specifically designed proposals extracted from the ship model combined with an improved saliency detection method. Firstly we creatively propose two ship models, the "V" ship head model and the "||" ship body one, to localize the ship proposals from the line segments extracted from a test image. Next, for offshore ships with relatively small sizes, which cannot be efficiently picked out by the ship models due to the lack of reliable line segments, we propose an improved saliency detection method to find these proposals. Therefore, these two kinds of ship proposals are fed to the trained CNN for robust and efficient detection. Experimental results on a large amount of representative remote sensing images with different kinds of ships with varied poses, shapes and scales demonstrate the efficiency and robustness of our proposed S-CNN-Based ship detector.

  7. S-CNN-BASED SHIP DETECTION FROM HIGH-RESOLUTION REMOTE SENSING IMAGES

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2016-06-01

    Full Text Available Reliable ship detection plays an important role in both military and civil fields. However, it makes the task difficult with high-resolution remote sensing images with complex background and various types of ships with different poses, shapes and scales. Related works mostly used gray and shape features to detect ships, which obtain results with poor robustness and efficiency. To detect ships more automatically and robustly, we propose a novel ship detection method based on the convolutional neural networks (CNNs, called SCNN, fed with specifically designed proposals extracted from the ship model combined with an improved saliency detection method. Firstly we creatively propose two ship models, the “V” ship head model and the “||” ship body one, to localize the ship proposals from the line segments extracted from a test image. Next, for offshore ships with relatively small sizes, which cannot be efficiently picked out by the ship models due to the lack of reliable line segments, we propose an improved saliency detection method to find these proposals. Therefore, these two kinds of ship proposals are fed to the trained CNN for robust and efficient detection. Experimental results on a large amount of representative remote sensing images with different kinds of ships with varied poses, shapes and scales demonstrate the efficiency and robustness of our proposed S-CNN-Based ship detector.

  8. Topography improvements in MEMS DMs for high-contrast, high-resolution imaging, Phase I

    Data.gov (United States)

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

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

    Data.gov (United States)

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

  10. Dual-conjugate adaptive optics for wide-field high-resolution retinal imaging.

    Science.gov (United States)

    Thaung, Jörgen; Knutsson, Per; Popovic, Zoran; Owner-Petersen, Mette

    2009-03-16

    We present analysis and preliminary laboratory testing of a real-time dual-conjugate adaptive optics (DCAO) instrument for ophthalmology that will enable wide-field high resolution imaging of the retina in vivo. The setup comprises five retinal guide stars (GS) and two deformable mirrors (DM), one conjugate to the pupil and one conjugate to a plane close to the retina. The DCAO instrument has a closed-loop wavefront sensing wavelength of 834 nm and an imaging wavelength of 575 nm. It incorporates an array of collimator lenses to spatially filter the light from all guide stars using one adjustable iris, and images the Hartmann patterns of multiple reference sources on a single detector. Zemax simulations were performed at 834 nm and 575 nm with the Navarro 99 and the Liou- Brennan eye models. Two correction alternatives were evaluated; conventional single conjugate AO (SCAO, using one GS and a pupil DM) and DCAO (using multiple GS and two DM). Zemax simulations at 575 nm based on the Navarro 99 eye model show that the diameter of the corrected field of view for diffraction-limited imaging (Strehl >or= 0.8) increases from 1.5 deg with SCAO to 6.5 deg using DCAO. The increase for the less stringent condition of a wavefront error of 1 rad or less (Strehl >or= 0.37) is from 3 deg with SCAO to approximately 7.4 deg using DCAO. Corresponding results for the Liou-Brennan eye model are 3.1 deg (SCAO) and 8.2 deg (DCAO) for Strehl >or= 0.8, and 4.8 deg (SCAO) and 9.6 deg (DCAO) for Strehl >or= 0.37. Potential gain in corrected field of view with DCAO is confirmed both by laboratory experiments on a model eye and by preliminary in vivo imaging of a human eye. (c) 2009 Optical Society of America

  11. DEM GENERATION FROM HIGH RESOLUTION SATELLITE IMAGES THROUGH A NEW 3D LEAST SQUARES MATCHING ALGORITHM

    Directory of Open Access Journals (Sweden)

    T. Kim

    2012-09-01

    Full Text Available Automated generation of digital elevation models (DEMs from high resolution satellite images (HRSIs has been an active research topic for many years. However, stereo matching of HRSIs, in particular based on image-space search, is still difficult due to occlusions and building facades within them. Object-space matching schemes, proposed to overcome these problem, often are very time consuming and critical to the dimensions of voxels. In this paper, we tried a new least square matching (LSM algorithm that works in a 3D object space. The algorithm starts with an initial height value on one location of the object space. From this 3D point, the left and right image points are projected. The true height is calculated by iterative least squares estimation based on the grey level differences between the left and right patches centred on the projected left and right points. We tested the 3D LSM to the Worldview images over 'Terrassa Sud' provided by the ISPRS WG I/4. We also compared the performance of the 3D LSM with the correlation matching based on 2D image space and the correlation matching based on 3D object space. The accuracy of the DEM from each method was analysed against the ground truth. Test results showed that 3D LSM offers more accurate DEMs over the conventional matching algorithms. Results also showed that 3D LSM is sensitive to the accuracy of initial height value to start the estimation. We combined the 3D COM and 3D LSM for accurate and robust DEM generation from HRSIs. The major contribution of this paper is that we proposed and validated that LSM can be applied to object space and that the combination of 3D correlation and 3D LSM can be a good solution for automated DEM generation from HRSIs.

  12. GAN-Assisted Two-Stream Neural Network for High-Resolution Remote Sensing Image Classification

    Directory of Open Access Journals (Sweden)

    Yiting Tao

    2017-12-01

    Full Text Available Using deep learning to improve the capabilities of high-resolution satellite images has emerged recently as an important topic in automatic classification. Deep networks track hierarchical high-level features to identify objects; however, enhancing the classification accuracy from low-level features is often disregarded. We therefore proposed a two-stream deep-learning neural network strategy, with a main stream utilizing fine spatial-resolution panchromatic images to retain low-level information under a supervised residual network structure. An auxiliary line employed an unsupervised net to extract high-level abstract and discriminative features from multispectral images to supplement the spectral information in the main stream. Various feature extraction types from the neural network were selected and jointed in the novel net, as the combined high- and low-level features could provide a superior solution to image classification. In traditional convolutional neural networks, increased network depth might not influence the network performance perceptibly; however, we introduced a residual neural network to develop the expressive ability of the deeper net, increasing the role of net depth in feature extraction. To enhance feature robustness, we proposed a novel consolidation part in feature extraction. An adversarial net improved the feature extraction capabilities and aided digging the inherent and discriminative features from data, with increased extraction efficacy. Tests on satellite images indicated the high overall accuracy of our novel net, verifying that net depth or number of convolution kernels affected the classification capability. Various comparative tests proved the structural rationality for our two-stream structure.

  13. The High Resolution Imaging Science Experiment (HiRISE) during MRO's Primary Science Phase (PSP)

    Science.gov (United States)

    McEwen, A.S.; Banks, M.E.; Baugh, N.; Becker, K.; Boyd, A.; Bergstrom, J.W.; Beyer, R.A.; Bortolini, E.; Bridges, N.T.; Byrne, S.; Castalia, B.; Chuang, F.C.; Crumpler, L.S.; Daubar, I.; Davatzes, A.K.; Deardorff, D.G.; DeJong, A.; Alan, Delamere W.; Dobrea, E.N.; Dundas, C.M.; Eliason, E.M.; Espinoza, Y.; Fennema, A.; Fishbaugh, K.E.; Forrester, T.; Geissler, P.E.; Grant, J. A.; Griffes, J.L.; Grotzinger, J.P.; Gulick, V.C.; Hansen, C.J.; Herkenhoff, K. E.; Heyd, R.; Jaeger, W.L.; Jones, D.; Kanefsky, B.; Keszthelyi, L.; King, R.; Kirk, R.L.; Kolb, K.J.; Lasco, J.; Lefort, A.; Leis, R.; Lewis, K.W.; Martinez-Alonso, S.; Mattson, S.; McArthur, G.; Mellon, M.T.; Metz, J.M.; Milazzo, M.P.; Milliken, R.E.; Motazedian, T.; Okubo, C.H.; Ortiz, A.; Philippoff, A.J.; Plassmann, J.; Polit, A.; Russell, P.S.; Schaller, C.; Searls, M.L.; Spriggs, T.; Squyres, S. W.; Tarr, S.; Thomas, N.; Thomson, B.J.; Tornabene, L.L.; Van Houten, C.; Verba, C.; Weitz, C.M.; Wray, J.J.

    2010-01-01

    The High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) acquired 8 terapixels of data in 9137 images of Mars between October 2006 and December 2008, covering ???0.55% of the surface. Images are typically 5-6 km wide with 3-color coverage over the central 20% of the swath, and their scales usually range from 25 to 60 cm/pixel. Nine hundred and sixty stereo pairs were acquired and more than 50 digital terrain models (DTMs) completed; these data have led to some of the most significant science results. New methods to measure and correct distortions due to pointing jitter facilitate topographic and change-detection studies at sub-meter scales. Recent results address Noachian bedrock stratigraphy, fluvially deposited fans in craters and in or near Valles Marineris, groundwater flow in fractures and porous media, quasi-periodic layering in polar and non-polar deposits, tectonic history of west Candor Chasma, geometry of clay-rich deposits near and within Mawrth Vallis, dynamics of flood lavas in the Cerberus Palus region, evidence for pyroclastic deposits, columnar jointing in lava flows, recent collapse pits, evidence for water in well-preserved impact craters, newly discovered large rayed craters, and glacial and periglacial processes. Of particular interest are ongoing processes such as those driven by the wind, impact cratering, avalanches of dust and/or frost, relatively bright deposits on steep gullied slopes, and the dynamic seasonal processes over polar regions. HiRISE has acquired hundreds of large images of past, present and potential future landing sites and has contributed to scientific and engineering studies of those sites. Warming the focal-plane electronics prior to imaging has mitigated an instrument anomaly that produces bad data under cold operating conditions. ?? 2009 Elsevier Inc.

  14. Clinical performance of high-resolution late gadolinium enhancement imaging with compressed sensing.

    Science.gov (United States)

    Basha, Tamer A; Akçakaya, Mehmet; Liew, Charlene; Tsao, Connie W; Delling, Francesca N; Addae, Gifty; Ngo, Long; Manning, Warren J; Nezafat, Reza

    2017-12-01

    To evaluate diagnostic image quality of 3D late gadolinium enhancement (LGE) with high isotropic spatial resolution (∼1.4 mm 3 ) images reconstructed from randomly undersampled k-space using LOw-dimensional-structure Self-learning and Thresholding (LOST). We prospectively enrolled 270 patients (181 men; 55 ± 14 years) referred for myocardial viability assessment. 3D LGE with isotropic spatial resolution of 1.4 ± 0.1 mm 3 was acquired at 1.5T using a LOST acceleration rate of 3 to 5. In a subset of 121 patients, 3D LGE or phase-sensitive LGE were acquired with parallel imaging with an acceleration rate of 2 for comparison. Two readers evaluated image quality using a scale of 1 (poor) to 4 (excellent) and assessed for scar presence. The McNemar test statistic was used to compare the proportion of detected scar between the two sequences. We assessed the association between image quality and characteristics (age, gender, torso dimension, weight, heart rate), using generalized linear models. Overall, LGE detection proportions for 3D LGE with LOST were similar between readers 1 and 2 (16.30% vs. 18.15%). For image quality, readers gave 85.9% and 80.0%, respectively, for images categorized as good or excellent. Overall proportion of scar presence was not statistically different from conventional 3D LGE (28% vs. 33% [P = 0.17] for reader 1 and 26% vs. 31% [P = 0.37] for reader 2). Increasing subject heart rate was associated with lower image quality (estimated slope = -0.009 (P = 0.001)). High-resolution 3D LGE with LOST yields good to excellent image quality in >80% of patients and identifies patients with LV scar at the same rate as conventional 3D LGE. 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1829-1838. © 2017 International Society for Magnetic Resonance in Medicine.

  15. High-frequency CMUT arrays for high-resolution medical imaging

    Science.gov (United States)

    Yeh, David T.; Oralkan, Omer; Ergun, Arif S.; Zhuang, Xuefeng; Wygant, Ira O.; Khuri-Yakub, Butrus T.

    2005-04-01

    Applications of ultrasonic imaging in fields such as dermatology, ophthalmology, and cardiovascular medicine require very high resolution. Limitations in existing transducer technologies inhibit the development of high-frequency arrays, which would allow the use of dynamic focusing and enable higher frame rates. As an alternative, capacitive micromachined ultrasonic transducer (CMUT) technology, using integrated circuit fabrication techniques, can provide arrays with the small dimensions required for high-frequency operation. We have designed and fabricated several linear and ring arrays of CMUTs to operate in the 10 to 50 MHz range. These new arrays are made with the wafer bonding process. The ring arrays in particular demonstrate the feasibility of thinning the transducer to aid packaging in intravascular applications. This study shows that CMUTs can be made for high-frequency operation. Both transducers for use in conventional and collapse-mode operation have been designed and characterized. The results demonstrate that CMUT is an appropriate technology for building high-frequency arrays. A linear array of high-voltage pulser and amplifier circuits has also been designed for use with an array of CMUTs to enable real-time imaging applications. Pulse-echo results from the sixteen-channel array have been demonstrated.

  16. High resolution magnetic resonance imaging of urethral anatomy in continent nulliparous pregnant women

    International Nuclear Information System (INIS)

    Preyer, Oliver; Brugger, Peter C.; Laml, Thomas; Hanzal, Engelbert; Prayer, Daniela; Umek, Wolfgang

    2011-01-01

    Introduction: To quantify the distribution of morphologic appearances of urethral anatomy and measure variables of urethral sphincter anatomy in continent, nulliparous, pregnant women by high resolution magnetic resonance imaging (MRI). Materials and methods: We studied fifteen women during their first pregnancy. We defined and quantified bladder neck and urethral morphology on axial and sagittal MR images from healthy, continent women. Results: The mean (±standard deviation) total transverse urethral diameter, anterior–posterior diameter, unilateral striated sphincter muscle thickness, and striated sphincter length were 15 ± 2 mm (range: 12–19 mm), 15 ± 2 mm (range: 11–20 mm), 2 ± 1 mm (range: 1–4 mm), and 13 ± 3 mm (range: 9–18 mm) respectively. The mean (±standard deviation) total urethral length on sagittal scans was 22 ± 3 mm (range: 17.6–26.4 mm). Discussion: Advances in MR technique combined with anatomical and histological findings will provide an insight to understand how changes in urethral anatomy might affect the continence mechanisms in pregnant and non-pregnant, continent or incontinent individuals.

  17. High-resolution X-ray imaging of the Starburst Galaxy M82

    Science.gov (United States)

    Bregman, Joel N.; Schulman, Eric; Tomisaka, Kohji

    1995-01-01

    Starburst galaxies are predicted to drive hot flows of gas from their central star-forming regions, and to test this expectation, a deep X-ray image was obtained of the nearby starburst galaxy M82 with the High-Resolution Imager (HRI) on the X-ray telescope ROSAT. Aside from three nuclear point sources, the flux is dominated by diffuse emission that we decompose into components along the disk and along the minor axis. The X-ray surface brightness of the disk component decreases exponentially with a scale length of 0.27 kpc, as does the optical line emission from warm ionized gas. This is not due to steady outflow of gas along the plane, but may indicate a rapid decrease in the star formation and energy input rate beyond the nuclear region. The X-ray emission along the minor axis is consistent with the outflow of gas in a jet that is partially confined within 1.6 kpc of the nucleus and expands freely at larger radii; this emission is detected to a distance of 6 kpc. In the center of M82, the hot gas density is 0.2-0.5/cu cm and the central gas pressure is P/k approximately = 0.3-3 x 10(exp 7) K/cu cm, which is similar to estimates of the pressure in the optical emission-line material and molecular gas.

  18. High-resolution multi-band imaging for validation and characterization of small Kepler planets

    International Nuclear Information System (INIS)

    Everett, Mark E.; Silva, David R.; Barclay, Thomas; Howell, Steve B.; Ciardi, David R.; Horch, Elliott P.; Crepp, Justin R.

    2015-01-01

    High-resolution ground-based optical speckle and near-infrared adaptive optics images are taken to search for stars in close angular proximity to host stars of candidate planets identified by the NASA Kepler Mission. Neighboring stars are a potential source of false positive signals. These stars also blend into Kepler light curves, affecting estimated planet properties, and are important for an understanding of planets in multiple star systems. Deep images with high angular resolution help to validate candidate planets by excluding potential background eclipsing binaries as the source of the transit signals. A study of 18 Kepler Object of Interest stars hosting a total of 28 candidate and validated planets is presented. Validation levels are determined for 18 planets against the likelihood of a false positive from a background eclipsing binary. Most of these are validated at the 99% level or higher, including five newly validated planets in two systems: Kepler-430 and Kepler-431. The stellar properties of the candidate host stars are determined by supplementing existing literature values with new spectroscopic characterizations. Close neighbors of seven of these stars are examined using multi-wavelength photometry to determine their nature and influence on the candidate planet properties. Most of the close neighbors appear to be gravitationally bound secondaries, while a few are best explained as closely co-aligned field stars. Revised planet properties are derived for each candidate and validated planet, including cases where the close neighbors are the potential host stars.

  19. Strategies for high-resolution imaging of epithelial ovarian cancer by laparoscopic nonlinear microscopy.

    Science.gov (United States)

    Williams, Rebecca M; Flesken-Nikitin, Andrea; Ellenson, Lora Hedrick; Connolly, Denise C; Hamilton, Thomas C; Nikitin, Alexander Yu; Zipfel, Warren R

    2010-06-01

    Ovarian cancer remains the most frequently lethal of the gynecologic cancers owing to the late detection of this disease. Here, by using human specimens and three mouse models of ovarian cancer, we tested the feasibility of nonlinear imaging approaches, the multiphoton microscopy (MPM) and second harmonic generation (SHG) to serve as complementary tools for ovarian cancer diagnosis. We demonstrate that MPM/SHG of intrinsic tissue emissions allows visualization of unfixed, unsectioned, and unstained tissues at a resolution comparable to that of routinely processed histologic sections. In addition to permitting discrimination between normal and neoplastic tissues according to pathological criteria, the method facilitates morphometric assessment of specimens and detection of very early cellular changes in the ovarian surface epithelium. A red shift in cellular intrinsic fluorescence and collagen structural alterations have been identified as additional cancer-associated changes that are indiscernible by conventional pathologic techniques. Importantly, the feasibility of in vivo laparoscopic MPM/SHG is demonstrated by using a "stick" objective lens. Intravital detection of neoplastic lesions has been further facilitated by low-magnification identification of an indicator for cathepsin activity followed by MPM laparoscopic imaging. Taken together, these results demonstrate that MPM may be translatable to clinical settings as an endoscopic approach suitable for high-resolution optical biopsies as well as a pathology tool for rapid initial assessment of ovarian cancer samples.

  20. Strategies for High-Resolution Imaging of Epithelial Ovarian Cancer by Laparoscopic Nonlinear Microscopy1

    Science.gov (United States)

    Williams, Rebecca M; Flesken-Nikitin, Andrea; Ellenson, Lora Hedrick; Connolly, Denise C; Hamilton, Thomas C; Nikitin, Alexander Yu; Zipfel, Warren R

    2010-01-01

    Ovarian cancer remains the most frequently lethal of the gynecologic cancers owing to the late detection of this disease. Here, by using human specimens and three mouse models of ovarian cancer, we tested the feasibility of nonlinear imaging approaches, the multiphoton microscopy (MPM) and second harmonic generation (SHG) to serve as complementary tools for ovarian cancer diagnosis. We demonstrate that MPM/SHG of intrinsic tissue emissions allows visualization of unfixed, unsectioned, and unstained tissues at a resolution comparable to that of routinely processed histologic sections. In addition to permitting discrimination between normal and neoplastic tissues according to pathological criteria, the method facilitates morphometric assessment of specimens and detection of very early cellular changes in the ovarian surface epithelium. A red shift in cellular intrinsic fluorescence and collagen structural alterations have been identified as additional cancer-associated changes that are indiscernible by conventional pathologic techniques. Importantly, the feasibility of in vivo laparoscopic MPM/SHG is demonstrated by using a “stick” objective lens. Intravital detection of neoplastic lesions has been further facilitated by low-magnification identification of an indicator for cathepsin activity followed by MPM laparoscopic imaging. Taken together, these results demonstrate that MPM may be translatable to clinical settings as an endoscopic approach suitable for high-resolution optical biopsies as well as a pathology tool for rapid initial assessment of ovarian cancer samples. PMID:20563260

  1. Learning Dual Multi-Scale Manifold Ranking for Semantic Segmentation of High-Resolution Images

    Directory of Open Access Journals (Sweden)

    Mi Zhang

    2017-05-01

    Full Text Available Semantic image segmentation has recently witnessed considerable progress by training deep convolutional neural networks (CNNs. The core issue of this technique is the limited capacity of CNNs to depict visual objects. Existing approaches tend to utilize approximate inference in a discrete domain or additional aides and do not have a global optimum guarantee. We propose the use of the multi-label manifold ranking (MR method in solving the linear objective energy function in a continuous domain to delineate visual objects and solve these problems. We present a novel embedded single stream optimization method based on the MR model to avoid approximations without sacrificing expressive power. In addition, we propose a novel network, which we refer to as dual multi-scale manifold ranking (DMSMR network, that combines the dilated, multi-scale strategies with the single stream MR optimization method in the deep learning architecture to further improve the performance. Experiments on high resolution images, including close-range and remote sensing datasets, demonstrate that the proposed approach can achieve competitive accuracy without additional aides in an end-to-end manner.

  2. High-Resolution CT Imaging of Single Breast Cancer Microcalcifications In Vivo

    Science.gov (United States)

    Inoue, Kazumasa; Liu, Fangbing; Hoppin, Jack; Lunsford, Elaine P.; Lackas, Christian; Hesterman, Jacob; Lenkinski, Robert E.; Fujii, Hirofumi; Frangioni, John V.

    2010-01-01

    Microcalcification is a hallmark of breast cancer and a key diagnostic feature for mammography. We recently described the first robust animal model of breast cancer microcalcification. In this study, we hypothesized that high-resolution computed tomography (CT) could potentially detect the genesis of a single microcalcification in vivo and quantify its growth over time. Using a commercial CT scanner, we systematically optimized acquisition and reconstruction parameters. Two ray-tracing image reconstruction algorithms were tested, a voxel-driven “fast” cone beam algorithm (FCBA) and a detector-driven “exact” cone beam algorithm (ECBA). By optimizing acquisition and reconstruction parameters, we were able to achieve a resolution of 104 µm full-width at half maximum (FWHM). At an optimal detector sampling frequency, ECBA provided a 28 µm (21%) FWHM improvement in resolution over FCBA. In vitro, we were able to image a single 300 µm by 100 µm hydroxyapatite crystal. In a syngeneic rat model of breast cancer, we were able to detect the genesis of a single microcalcification in vivo and follow its growth longitudinally over weeks. Taken together, this study provides an in vivo “gold standard” for the development of calcification-specific contrast agents and a model system for studying the mechanism of breast cancer microcalcification. PMID:21504703

  3. Fluorescent-protein stabilization and high-resolution imaging of cleared, intact mouse brains.

    Directory of Open Access Journals (Sweden)

    Martin K Schwarz

    Full Text Available In order to observe and quantify long-range neuronal connections in intact mouse brain by light microscopy, it is first necessary to clear the brain, thus suppressing refractive-index variations. Here we describe a method that clears the brain and preserves the signal from proteinaceous fluorophores using a pH-adjusted non-aqueous index-matching medium. Successful clearing is enabled through the use of either 1-propanol or tert-butanol during dehydration whilst maintaining a basic pH. We show that high-resolution fluorescence imaging of entire, structurally intact juvenile and adult mouse brains is possible at subcellular resolution, even following many months in clearing solution. We also show that axonal long-range projections that are EGFP-labelled by modified Rabies virus can be imaged throughout the brain using a purpose-built light-sheet fluorescence microscope. To demonstrate the viability of the technique, we determined a detailed map of the monosynaptic projections onto a target cell population in the lateral entorhinal cortex. This example demonstrates that our method permits the quantification of whole-brain connectivity patterns at the subcellular level in the uncut brain.

  4. On-board optical image compression for future high-resolution remote sensing systems

    Science.gov (United States)

    Lambert-Nebout, Catherine; Latry, Christophe; Moury, Gilles A.; Parisot, Christophe; Antonini, Marc; Barlaud, Michel

    2000-12-01

    Future high resolution instruments planned by CNES to succeed SPOT5 will lead to higher bit rates because of the increase in both resolution and number of bits per pixel, not compensated by the reduced swatch. Data compression is then needed, with compression ratio goals higher than the 2.81 SPOT5 value obtained with a JPEG like algorithm. Compression ratio should rise typically to 4 - 6 values, with artifacts remaining unnoticeable: SPOT5 algorithm performances have clearly to be outdone. On another hand, in the framework of optimized and low cost instruments, noise level will increase. Furthermore, the Modulation Transfer Function (MTF) and the sampling grid will be fitted together, to -- at least roughly -- satisfy Shannon requirements. As with the Supermode sampling scheme of the SPOT5 Panchromatic band, the images will have to be restored (deconvolution and denoising) and that renders the compression impact assessment much more complex. This paper is a synthesis of numerous studies evaluating several data compression algorithms, some of them supposing that the adaptation between sampling grid and MTF is obtained by the quincunx Supermode scheme. The following points are analyzed: compression decorrelator (DCT, LOT, wavelet, lifting), comparison with JPEG2000 for images acquired on a square grid, compression fitting to the quincunx sampling and on board restoration (before compression) versus on ground restoration. For each of them, we describe the proposed solutions, underlining the associated complexity and comparing them from a quantitative and qualitative point of view, giving the results of experts analyses.

  5. Feasibility of high-resolution MR imaging for the diagnosis of intracranial vertebrobasilar artery dissection

    Energy Technology Data Exchange (ETDEWEB)

    Han, Miran; Rim, Nae-Jung; Kim, Sun Yong; Choi, Jin Wook [Ajou University School of Medicine, Ajou University Medical Center, Department of Radiology, Suwon (Korea, Republic of); Lee, Jin Soo [Ajou University School of Medicine, Ajou University Medical Center, Department of Neurology, Suwon (Korea, Republic of)

    2014-12-15

    To evaluate the feasibility of high-resolution MRI (HR-MRI) for diagnosing intracranial vertebrobasilar artery dissection (VBD) and to identify the most useful imaging findings suggesting dissection. We retrospectively reviewed 50 patients with suspected intracranial VBDs who underwent HR-MRI. Two neuroradiologists independently reviewed the HR-MR images. The diagnosis based on HR-MRI was compared with the final diagnosis by consensus among the neuroradiologists, neurointerventionist, and neurologist. Two neuroradiologists also sought signs of dissection (mural hematoma, dissection flap, outer-diameter enlargement on T2WI of steno-occlusive lesions). Inter- and intraobserver agreements were analysed. HR-MRI corroborated the final diagnosis in 47 (94 %; 31 VBD and 16 non-VBD) patients. A mural haematoma was best detected on T1WI and contrast-enhanced (CE)-T1WI (54.3 %). Dissection flaps were observed in almost all cases on CE-T1WI (91.4 %), and then were detected on T2WI (68.6 %). Outer-diameter enlargement of the steno-occlusive lesions on angiography was detected in more than half of the cases (62.9 %). The two reviewers showed almost perfect agreement for the diagnosis of VBD and detecting dissection signs on every sequence. HR-MRI can be a useful and non-invasive diagnostic tool for intracranial VBD, and dissection flaps on CE-T1WI are the signs with the greatest diagnostic value. (orig.)

  6. Deep Learning Based Oil Palm Tree Detection and Counting for High-Resolution Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Weijia Li

    2016-12-01

    Full Text Available Oil palm trees are important economic crops in Malaysia and other tropical areas. The number of oil palm trees in a plantation area is important information for predicting the yield of palm oil, monitoring the growing situation of palm trees and maximizing their productivity, etc. In this paper, we propose a deep learning based framework for oil palm tree detection and counting using high-resolution remote sensing images for Malaysia. Unlike previous palm tree detection studies, the trees in our study area are more crowded and their crowns often overlap. We use a number of manually interpreted samples to train and optimize the convolutional neural network (CNN, and predict labels for all the samples in an image dataset collected through the sliding window technique. Then, we merge the predicted palm coordinates corresponding to the same palm tree into one palm coordinate and obtain the final palm tree detection results. Based on our proposed method, more than 96% of the oil palm trees in our study area can be detected correctly when compared with the manually interpreted ground truth, and this is higher than the accuracies of the other three tree detection methods used in this study.

  7. Median filters as a tool to determine dark noise thresholds in high resolution smartphone image sensors for scientific imaging

    Science.gov (United States)

    Igoe, Damien P.; Parisi, Alfio V.; Amar, Abdurazaq; Rummenie, Katherine J.

    2018-01-01

    An evaluation of the use of median filters in the reduction of dark noise in smartphone high resolution image sensors is presented. The Sony Xperia Z1 employed has a maximum image sensor resolution of 20.7 Mpixels, with each pixel having a side length of just over 1 μm. Due to the large number of photosites, this provides an image sensor with very high sensitivity but also makes them prone to noise effects such as hot-pixels. Similar to earlier research with older models of smartphone, no appreciable temperature effects were observed in the overall average pixel values for images taken in ambient temperatures between 5 °C and 25 °C. In this research, hot-pixels are defined as pixels with intensities above a specific threshold. The threshold is determined using the distribution of pixel values of a set of images with uniform statistical properties associated with the application of median-filters of increasing size. An image with uniform statistics was employed as a training set from 124 dark images, and the threshold was determined to be 9 digital numbers (DN). The threshold remained constant for multiple resolutions and did not appreciably change even after a year of extensive field use and exposure to solar ultraviolet radiation. Although the temperature effects' uniformity masked an increase in hot-pixel occurrences, the total number of occurrences represented less than 0.1% of the total image. Hot-pixels were removed by applying a median filter, with an optimum filter size of 7 × 7; similar trends were observed for four additional smartphone image sensors used for validation. Hot-pixels were also reduced by decreasing image resolution. The method outlined in this research provides a methodology to characterise the dark noise behavior of high resolution image sensors for use in scientific investigations, especially as pixel sizes decrease.

  8. Cadastral Resurvey using High Resolution Satellite Ortho Image - challenges: A case study in Odisha, India

    Science.gov (United States)

    Parida, P. K.; Sanabada, M. K.; Tripathi, S.

    2014-11-01

    Advancements in satellite sensor technology enabling capturing of geometrically accurate images of earth's surface coupled with DGPS/ETS and GIS technology holds the capability of large scale mapping of land resources at cadastral level. High Resolution Satellite Images depict field bunds distinctly. Thus plot parcels are to be delineated from cloud free ortho-images and obscured/difficult areas are to be surveyed using DGPS and ETS. The vector datasets thus derived through RS/DGPS/ETS survey are to be integrated in GIS environment to generate the base cadastral vector datasets for further settlement/title confirmation activities. The objective of this paper is to illustrate the efficacy of a hybrid methodology employed in Pitambarpur Sasana village under Digapahandi Tahasil of Ganjam district, as a pilot project, particularly in Odisha scenario where the land parcel size is very small. One of the significant observations of the study is matching of Cadastral map area i.e. 315.454 Acres, the image map area i.e. 314.887 Acres and RoR area i.e. 313.815 Acre. It was revealed that 79 % of plots derived by high-tech survey method show acceptable level of accuracy despite the fact that the mode of area measurement by ground and automated method has significant variability. The variations are more in case of Government lands, Temple/Trust lands, Common Property Resources and plots near to river/nalas etc. The study indicates that the adopted technology can be extended to other districts and cadastral resurvey and updating work can be done for larger areas of the country using this methodology.

  9. The first high resolution image of coronal gas in a starbursting cool core cluster

    Science.gov (United States)

    Johnson, Sean

    2017-08-01

    Galaxy clusters represent a unique laboratory for directly observing gas cooling and feedback due to their high masses and correspondingly high gas densities and temperatures. Cooling of X-ray gas observed in 1/3 of clusters, known as cool-core clusters, should fuel star formation at prodigious rates, but such high levels of star formation are rarely observed. Feedback from active galactic nuclei (AGN) is a leading explanation for the lack of star formation in most cool clusters, and AGN power is sufficient to offset gas cooling on average. Nevertheless, some cool core clusters exhibit massive starbursts indicating that our understanding of cooling and feedback is incomplete. Observations of 10^5 K coronal gas in cool core clusters through OVI emission offers a sensitive means of testing our understanding of cooling and feedback because OVI emission is a dominant coolant and sensitive tracer of shocked gas. Recently, Hayes et al. 2016 demonstrated that synthetic narrow-band imaging of OVI emission is possible through subtraction of long-pass filters with the ACS+SBC for targets at z=0.23-0.29. Here, we propose to use this exciting new technique to directly image coronal OVI emitting gas at high resolution in Abell 1835, a prototypical starbursting cool-core cluster at z=0.252. Abell 1835 hosts a strong cooling core, massive starburst, radio AGN, and at z=0.252, it offers a unique opportunity to directly image OVI at hi-res in the UV with ACS+SBC. With just 15 orbits of ACS+SBC imaging, the proposed observations will complete the existing rich multi-wavelength dataset available for Abell 1835 to provide new insights into cooling and feedback in clusters.

  10. A Micro Saddle Coil with Switchable Sensitivity for Local High-Resolution Imaging of Luminal Tissue

    Directory of Open Access Journals (Sweden)

    Tetsuji Dohi

    2016-04-01

    Full Text Available This paper reports on a micro saddle coil for local high-resolution magnetic resonance imaging (MRI fabricated by embedding a flexible coil pattern into a polydimethyilsiloxane (PDMS tube. We can change the sensitivity of the micro coil by deforming the shape of the coil from a saddle-shaped mode to a planar-shaped mode. The inductance, the resistance, and the Q-factor of the coil in the saddle-shaped mode were 2.45 μH, 3.31 Ω, and 39.9, respectively. Those of the planar-shaped mode were 3.07 μH, 3.92 Ω, and 42.9, respectively. In MRI acquired in saddle-shaped mode, a large visible area existed around the coil. Although the sensitive area was considerably reduced in the planar-shaped mode, clear MRI images were obtained. The signal-to-noise ratios (SNR of the saddle-shaped and planar-shaped modes were 194.9 and 505.9, respectively, at voxel size of 2.0 × 2.0 × 2.0 mm3 and 11.7 and 37.4, respectively, at voxel size of 0.5 × 0.5 × 1.0 mm3. The sensitivity of the saddle-shaped and the planar-shaped modes were about 3 times and 10 times higher, respectively, than those of the medical head coil at both voxel sizes. Thus, the micro saddle coil enabled large-area imaging and highly sensitive imaging by switching the shape of the coil.

  11. Tiger Stripes and Cassini ISS High-Resolution Imaging of Enceladus

    Science.gov (United States)

    Helfenstein, Paul; Denk, T.; Giese, B.; McEwen, A. S.; Neukum, G.; Perry, J.; Porco, C. C.; Thomas, P. C.; Turtle, E.; Verbiscer, A.; Veverka, J.

    2008-09-01

    Deciphering the mechanisms of Enceladus’ plumes is one of the most important and challenging tasks for planetary science. Cassini has provided a wealth of data by remote and in-situ data collection, but fundamental details of the vents and their context remain elusive. Three flybys of Enceladus by Cassini in 2008, on August 11 (altitude: 50km), October 9 (30km), and October 31 (200 km) are designed to further our knowledge of Enceladus’ geology and geophysics. Anticipated data include images as good as 7 m/pixel of parts of the geologically active South Polar Terrain (SPT). We targeted six different known eruption sites (Spitale and Porco 2007, Nature 449, 695-697) along Cairo Sulcus, Baghdad Suclus, and Damascus Sulcus, as well as non-active portions of the the "tiger stripes" and bright grooved terrain in between. On each of the three flybys we also plan contiguous ISS broadband multi-spectral mosaics of the entire SPT region so that we can search for volcanically and tectonically driven temporal changes and construct detailed digital terrain maps. Previous images of the tiger stripes and other rift systems on Enceladus resolve geomorphic structures on hundred meter scales or larger. Within those resolution limits, tiger stripes are morphologically distinguished most strongly from comparably sized young looking rifts elsewhere on Enceladus by their prominent upturned flanks, the muted appearance of their surface relief, and their relative absence of distinct cliff faces, probably of solid ice along scarps. The anticipated new high-resolution images will provide critical structural details needed to identify the extent to which unique attributes of tiger stripes are caused by mantling by plume fallout, tectonic deformation, seismic disruption, or perhaps thermal processes. Here, we present a first analysis of the August 11 close flyby images.

  12. Biofouling patterns in spacer filled channels: High resolution imaging for characterization of heterogeneous biofilms

    KAUST Repository

    Staal, Marc

    2017-08-15

    Biofilms develop in heterogeneous patterns at a µm scale up to a cm scale, and patterns become more pronounced when biofilms develop under complex hydrodynamic flow regimes. Spatially heterogeneous biofilms are especially known in spiral wound reverse osmosis (RO) and nanofiltration (NF) membrane filtration systems used for desalination and wastewater reuse to produce high quality (drinking) water. These spiral wound membrane modules contain mesh-like spacer structures used to create an intermembrane space and improve water mixing. Spacers create inhomogeneous water flow patterns resulting in zones favouring biofilm growth, possibly leading to biofouling thus hampering water production. Oxygen sensing planar optodes were used to visualize variations in oxygen decrease rates (ODR). ODR is an indication of biofilm activity. In this study, ODR images of multiple repetitive spacer areas in a membrane fouling simulator were averaged to produce high resolution, low noise ODR images. Averaging 40 individual spacer areas improved the ODR distribution image significantly and allowed comparison of biofilm patterning over a spacer structure at different positions in an RO filter. This method clearly showed that most active biofilm accumulated on and in direct vicinity of the spacer. The averaging method was also used to calculate the deviation of ODR patterning from individual spacer areas to the average ODR pattern, proposing a new approach to determine biofilm spatial heterogeneity. This study showed that the averaging method can be applied and that the improved, averaged ODR images can be used as an analytical, in-situ, non-destructive method to assess and quantify the effect of membrane installation operational parameters or different spacer geometries on biofilm development in spiral wound membrane systems characterized by complex hydrodynamic conditions.

  13. Content-Based High-Resolution Remote Sensing Image Retrieval via Unsupervised Feature Learning and Collaborative Affinity Metric Fusion

    Directory of Open Access Journals (Sweden)

    Yansheng Li

    2016-08-01

    Full Text Available With the urgent demand for automatic management of large numbers of high-resolution remote sensing images, content-based high-resolution remote sensing image retrieval (CB-HRRS-IR has attracted much research interest. Accordingly, this paper proposes a novel high-resolution remote sensing image retrieval approach via multiple feature representation and collaborative affinity metric fusion (IRMFRCAMF. In IRMFRCAMF, we design four unsupervised convolutional neural networks with different layers to generate four types of unsupervised features from the fine level to the coarse level. In addition to these four types of unsupervised features, we also implement four traditional feature descriptors, including local binary pattern (LBP, gray level co-occurrence (GLCM, maximal response 8 (MR8, and scale-invariant feature transform (SIFT. In order to fully incorporate the complementary information among multiple features of one image and the mutual information across auxiliary images in the image dataset, this paper advocates collaborative affinity metric fusion to measure the similarity between images. The performance evaluation of high-resolution remote sensing image retrieval is implemented on two public datasets, the UC Merced (UCM dataset and the Wuhan University (WH dataset. Large numbers of experiments show that our proposed IRMFRCAMF can significantly outperform the state-of-the-art approaches.

  14. Companions in Color: High-Resolution Imaging of Kepler’s Sub-Neptune Host Stars

    Science.gov (United States)

    Ware, Austin; Wolfgang, Angie; Kannan, Deepti

    2018-01-01

    A current problem in astronomy is determining how sub-Neptune-sized exoplanets form in planetary systems. These kinds of planets, which fall between 1 and 4 times the size of Earth, were discovered in abundance by the Kepler Mission and were typically found with relatively short orbital periods. The combination of their size and orbital period make them unusual in relation to the Solar System, leading to the question of how these exoplanets form and evolve. One possibility is that they have been influenced by distant stellar companions. To help assess the influence of these objects on the present-day, observed properties of exoplanets, we conduct a NIR search for visual stellar companions to the stars around which the Kepler Mission discovered planets. We use high-resolution images obtained with the adaptive optics systems at the Lick Observatory Shane-3m telescope to find these companion stars. Importantly, we also determine the effective brightness and distance from the planet-hosting star at which it is possible to detect these companions. Out of the 200 KOIs in our sample, 42 KOIs (21%) have visual companions within 3”, and 90 (46%) have them within 6”. These findings are consistent with recent high-resolution imaging from Furlan et al. 2017 that found at least one visual companion within 4” for 31% of sampled KOIs (37% within 4" for our sample). Our results are also complementary to Furlan et al. 2017, with only 17 visual companions commonly detected in the same filter. As for detection limits, our preliminary results indicate that we can detect companion stars < 3-5 magnitudes fainter than the planet-hosting star at a separation of ~ 1”. These detection limits will enable us to determine the probability that possible companion stars could be hidden within the noise around the planet-hosting star, an important step in determining the frequency with which these short-period, sub-Neptune-sized planets occur within binary star systems.

  15. High Resolution Depth-Resolved Imaging From Multi-Focal Images for Medical Ultrasound

    DEFF Research Database (Denmark)

    Diamantis, Konstantinos; Dalgarno, Paul A.; Greenaway, Alan H.

    2015-01-01

    An ultrasound imaging technique providing subdiffraction limit axial resolution for point sources is proposed. It is based on simultaneously acquired multi-focal images of the same object, and on the image metric of sharpness. The sharpness is extracted by image data and presents higher values...... for in-focus images. The technique is derived from biological microscopy and is validated here with simulated ultrasound data. A linear array probe is used to scan a point scatterer phantom that moves in depth with a controlled step. From the beamformed responses of each scatterer position the image...... calibration curves combined with the use of a maximum-likelihood algorithm is then able to estimate, with high precision, the depth location of any emitter fron each single image. Estimated values are compared with the ground truth demonstrating that an accuracy of 28.6 µm (0.13λ) is achieved for a 4 mm depth...

  16. Detection of Thermal Erosion Gullies from High-Resolution Images Using Deep Learning

    Science.gov (United States)

    Huang, L.; Liu, L.; Jiang, L.; Zhang, T.; Sun, Y.

    2017-12-01

    Thermal erosion gullies, one type of thermokarst landforms, develop due to thawing of ice-rich permafrost. Mapping the location and extent of thermal erosion gullies can help understand the spatial distribution of thermokarst landforms and their temporal evolution. Remote sensing images provide an effective way for mapping thermokarst landforms, especially thermokarst lakes. However, thermal erosion gullies are challenging to map from remote sensing images due to their small sizes and significant variations in geometric/radiometric properties. It is feasible to manually identify these features, as a few previous studies have carried out. However manual methods are labor-intensive, therefore, cannot be used for a large study area. In this work, we conduct automatic mapping of thermal erosion gullies from high-resolution images by using Deep Learning. Our study area is located in Eboling Mountain (Qinghai, China). Within a 6 km2 peatland area underlain by ice-rich permafrost, at least 20 thermal erosional gullies are well developed. The image used is a 15-cm-resolution Digital Orthophoto Map (DOM) generated in July 2016. First, we extracted 14 gully patches and ten non-gully patches as training data. And we performed image augmentation. Next, we fine-tuned the pre-trained model of DeepLab, a deep-learning algorithm for semantic image segmentation based on Deep Convolutional Neural Networks. Then, we performed inference on the whole DOM and obtained intermediate results in forms of polygons for all identified gullies. At last, we removed misidentified polygons based on a few pre-set criteria on the size and shape of each polygon. Our final results include 42 polygons. Validated against field measurements using GPS, most of the gullies are detected correctly. There are 20 false detections due to the small number and low quality of training images. We also found three new gullies that missed in the field observations. This study shows that (1) despite a challenging

  17. High-resolution optical coherence tomography imaging of the living kidney.

    Science.gov (United States)

    Andrews, Peter M; Chen, Yu; Onozato, Maristela L; Huang, Shu-Wei; Adler, Desmond C; Huber, Robert A; Jiang, James; Barry, Scott E; Cable, Alex E; Fujimoto, James G

    2008-04-01

    Optical coherence tomography (OCT) is a rapidly emerging imaging modality that can provide non-invasive, cross-sectional, high-resolution images of tissue morphology in situ and in real-time. In the present series of studies, we used a high-speed OCT imaging system equipped with a frequency-swept laser light source (1.3 mum wavelength) to study living kidneys in situ. Adult, male Munich-Wistar rats were anesthetized, a laparotomy was performed and the living kidneys were exposed for in situ observation. We observed the kidneys prior to, during and following exposure to renal ischemia induced by clamping the renal artery. The effects of intravenous mannitol infusion (1.0 ml of 25%) prior to and during renal ischemia were also studied. Finally, living kidneys were flushed with a renal preservation solution, excised and observed while being stored at 0-4 degrees C. Three-dimensional OCT data sets enabled visualization of the morphology of the uriniferous tubules and the renal corpuscles. When renal ischemia was induced, OCT revealed dramatic shrinkage of tubular lumens due to swelling of the lining epithelium. Three-dimensional visualization and volumetric rendering software provided an accurate evaluation of volumetric changes in tubular lumens in response to renal ischemia. Observations of kidneys flushed with a renal preservation solution and stored at 0-4 degrees C also revealed progressive and significant loss of tubular integrity over time. Intravenous infusion of mannitol solution resulted in thinning of the tubular walls and an increase in the tubular lumen diameters. Mannitol infusion also prevented the cell swelling that otherwise resulted in shrinkage of proximal tubule lumens during ischemia. We conclude that OCT represents an exciting new approach to visualize, in real-time, pathological changes in the living kidney in a non-invasive fashion. Possible clinical applications are discussed.

  18. CYCLOPS2: the fibre image slicer upgrade for the UCLES high resolution spectrograph

    Science.gov (United States)

    Horton, Anthony; Tinney, C. G.; Case, Scott; Farrell, Tony; Gers, Luke; Jones, Damien; Lawrence, Jon; Miziarski, Stan; Staszak, Nick; Orr, David; Vuong, Minh; Waller, Lew; Zhelem, Ross

    2012-09-01

    CYCLOPS2 is an upgrade for the UCLES high resolution spectrograph on the Anglo-Australian Telescope, scheduled for commissioning in semester 2012A. By replacing the 5 mirror Coudé train with a Cassegrain mounted fibre-based image slicer CYCLOPS2 simultaneously provides improved throughput, reduced aperture losses and increased spectral resolution. Sixteen optical fibres collect light from a 5.0 arcsecond2 area of sky and reformat it into the equivalent of a 0.6 arcsecond wide slit, delivering a spectral resolution of R= 70000 and up to twice as much flux as the standard 1 arcsecond slit of the Coudé train. CYCLOPS2 also adds support for simultaneous ThAr wavelength calibration via a dedicated fibre. CYCLOPS2 consists of three main components, the fore-optics unit, fibre bundle and slit unit. The fore optics unit incorporates magnification optics and a lenslet array and is designed to mount to the CURE Cassegrain instrument interface, which provides acquisition, guiding and calibration facilities. The fibre bundle transports the light from the Cassegrain focus to the UCLES spectrograph at Coudé and also includes a fibre mode scrambler. The slit unit consists of the fibre slit and relay optics to project an image of the slit onto the entrance aperture of the UCLES spectrograph. CYCLOPS2 builds on experience with the first generation CYCLOPS fibre system, which we also describe in this paper. We present the science case for an image slicing fibre feed for echelle spectroscopy and describe the design of CYCLOPS and CYCLOPS2.

  19. Image-based motion compensation for high-resolution extremities cone-beam CT

    Science.gov (United States)

    Sisniega, A.; Stayman, J. W.; Cao, Q.; Yorkston, J.; Siewerdsen, J. H.; Zbijewski, W.

    2016-03-01

    Purpose: Cone-beam CT (CBCT) of the extremities provides high spatial resolution, but its quantitative accuracy may be challenged by involuntary sub-mm patient motion that cannot be eliminated with simple means of external immobilization. We investigate a two-step iterative motion compensation based on a multi-component metric of image sharpness. Methods: Motion is considered with respect to locally rigid motion within a particular region of interest, and the method supports application to multiple locally rigid regions. Motion is estimated by maximizing a cost function with three components: a gradient metric encouraging image sharpness, an entropy term that favors high contrast and penalizes streaks, and a penalty term encouraging smooth motion. Motion compensation involved initial coarse estimation of gross motion followed by estimation of fine-scale displacements using high resolution reconstructions. The method was evaluated in simulations with synthetic motion (1-4 mm) applied to a wrist volume obtained on a CMOS-based CBCT testbench. Structural similarity index (SSIM) quantified the agreement between motion-compensated and static data. The algorithm was also tested on a motion contaminated patient scan from dedicated extremities CBCT. Results: Excellent correction was achieved for the investigated range of displacements, indicated by good visual agreement with the static data. 10-15% improvement in SSIM was attained for 2-4 mm motions. The compensation was robust against increasing motion (4% decrease in SSIM across the investigated range, compared to 14% with no compensation). Consistent performance was achieved across a range of noise levels. Significant mitigation of artifacts was shown in patient data. Conclusion: The results indicate feasibility of image-based motion correction in extremities CBCT without the need for a priori motion models, external trackers, or fiducials.

  20. High-resolution nondestructive testing of multilayer dielectric materials using wideband microwave synthetic aperture radar imaging

    Science.gov (United States)

    Kim, Tae Hee; James, Robin; Narayanan, Ram M.

    2017-04-01

    Fiber Reinforced Polymer or Plastic (FRP) composites have been rapidly increasing in the aerospace, automotive and marine industry, and civil engineering, because these composites show superior characteristics such as outstanding strength and stiffness, low weight, as well as anti-corrosion and easy production. Generally, the advancement of materials calls for correspondingly advanced methods and technologies for inspection and failure detection during production or maintenance, especially in the area of nondestructive testing (NDT). Among numerous inspection techniques, microwave sensing methods can be effectively used for NDT of FRP composites. FRP composite materials can be produced using various structures and materials, and various defects or flaws occur due to environmental conditions encountered during operation. However, reliable, low-cost, and easy-to-operate NDT methods have not been developed and tested. FRP composites are usually produced as multilayered structures consisting of fiber plate, matrix and core. Therefore, typical defects appearing in FRP composites are disbondings, delaminations, object inclusions, and certain kinds of barely visible impact damages. In this paper, we propose a microwave NDT method, based on synthetic aperture radar (SAR) imaging algorithms, for stand-off imaging of internal delaminations. When a microwave signal is incident on a multilayer dielectric material, the reflected signal provides a good response to interfaces and transverse cracks. An electromagnetic wave model is introduced to delineate interface widths or defect depths from the reflected waves. For the purpose of numerical analysis and simulation, multilayered composite samples with various artificial defects are assumed, and their SAR images are obtained and analyzed using a variety of high-resolution wideband waveforms.

  1. High-Resolution Inflorescence Phenotyping Using a Novel Image-Analysis Pipeline, PANorama.

    Science.gov (United States)

    Crowell, Samuel; Falcão, Alexandre X; Shah, Ankur; Wilson, Zachary; Greenberg, Anthony J; McCouch, Susan R

    2014-06-01

    Variation in inflorescence development is an important target of selection for numerous crop species, including many members of the Poaceae (grasses). In Asian rice (Oryza sativa), inflorescence (panicle) architecture is correlated with yield and grain-quality traits. However, many rice breeders continue to use composite phenotypes in selection pipelines, because measuring complex, branched panicles requires a significant investment of resources. We developed an open-source phenotyping platform, PANorama, which measures multiple architectural and branching phenotypes from images simultaneously. PANorama automatically extracts skeletons from images, allows users to subdivide axes into individual internodes, and thresholds away structures, such as awns, that normally interfere with accurate panicle phenotyping. PANorama represents an improvement in both efficiency and accuracy over existing panicle imaging platforms, and flexible implementation makes PANorama capable of measuring a range of organs from other plant species. Using high-resolution phenotypes, a mapping population of recombinant inbred lines, and a dense single-nucleotide polymorphism data set, we identify, to our knowledge, the largest number of quantitative trait loci (QTLs) for panicle traits ever reported in a single study. Several areas of the genome show pleiotropic clusters of panicle QTLs, including a region near the rice Green Revolution gene SEMIDWARF1. We also confirm that multiple panicle phenotypes are distinctly different among a small collection of diverse rice varieties. Taken together, these results suggest that clusters of small-effect QTLs may be responsible for varietal or subpopulation-specific panicle traits, representing a significant opportunity for rice breeders selecting for yield performance across different genetic backgrounds. © 2014 American Society of Plant Biologists. All Rights Reserved.

  2. High Resolution Energetic X-ray Imager (HREXI) for a Prototype 12U CubeSat

    Science.gov (United States)

    Hong, JaeSub; Allen, Branden; Grindlay, Jonathan E.; Barthelmy, Scott Douglas; Harrison, Fiona

    2017-08-01

    Our High Resolution Energetic X-ray Imager (HREXI) program is developing an Engineering Model (EM) for a 12U CubeSat wide-field hard X-ray (3-200 keV) coded-aperture imaging telescope. HREXI employs an array of CdZnTe (CZT) detectors (each 2 x 2 x 0.3 cm) with a fine-pixellated Tungsten coded aperture mask. The detector assembly utilizes the new technology of Through-Silicon-Vias (TSVs) to control and readout signals from the ASIC bonded to each CZT. TSVs eliminate the need for conventional wire-bonds for electric connections between the ASIC and back end electronics, greatly lowering the assembly complexity and cost, and thus enabling close-tiling of HREXI detectors in a small form factor with comfortable margins. For HREXI EM, we have successfully implemented TSVs on NuSTAR ASICs, which can cover an energy range of 3-200 keV with a FWHM spectral resolution of 1-2 keV. The 12U CubeSat HREXI EM prototype with 64 CZT detectors would image 0.5 sr of sky with FWHM field of view with 11 arcmin resolution for the current generation of the TSV-ASIC and a 20 cm mask - detector plane separation. A flight test of this 12U-HREXI will be proposed after full development and environmental testing to enable a future proposed array of SmallSat-HREXI telescopes with ~2 arcmin resolution for simultaneous full-sky studies of high redshift GRBs and a wide range of transients in the post-Swift era. (This work is supported by NASA grant NNX17AE62G)

  3. High resolution imaging of the mitral valve in the natural state with 7 Tesla MRI.

    Science.gov (United States)

    Stephens, Sam E; Liachenko, Serguei; Ingels, Neil B; Wenk, Jonathan F; Jensen, Morten O

    2017-01-01

    Imaging techniques of the mitral valve have improved tremendously during the last decade, but challenges persist. The delicate changes in annulus shape and papillary muscle position throughout the cardiac cycle have significant impact on the stress distribution in the leaflets and chords, thus preservation of anatomically accurate positioning is critical. The aim of this study was to develop an in vitro method and apparatus for obtaining high-resolution 3D MRI images of porcine mitral valves in both the diastolic and systolic configurations with physiologically appropriate annular shape, papillary muscle positions and orientations, specific to the heart from which the valve was harvested. Positioning and mounting was achieved through novel, customized mounting hardware consisting of papillary muscle and annulus holders with geometries determined via pre-mortem ultrasonic intra-valve measurements. A semi-automatic process was developed and employed to tailor Computer Aided Design models of the holders used to mount the valve. All valve mounting hardware was 3D printed using a stereolithographic printer, and the material of all fasteners used were brass for MRI compatibility. The mounted valves were placed within a clear acrylic case, capable of holding a zero-pressure and pressurized liquid bath of a MRI-compatible fluid. Obtaining images from the valve submerged in liquid fluid mimics the natural environment surrounding the valve, avoiding artefacts due to tissue surface tension mismatch and gravitational impact on tissue shape when not neutrally buoyant. Fluid pressure was supplied by reservoirs held at differing elevations and monitored and controlled to within ±1mmHg to ensure that the valves remained steady. The valves were scanned in a 7 Tesla MRI system providing a voxel resolution of at least 80μm. The systematic approach produced 3D datasets of high quality which, when combined with physiologically accurate positioning by the apparatus, can serve as an

  4. A data model and database for high-resolution pathology analytical image informatics

    Directory of Open Access Journals (Sweden)

    Fusheng Wang

    2011-01-01

    Full Text Available Background: The systematic analysis of imaged pathology specimens often results in a vast amount of morphological information at both the cellular and sub-cellular scales. While microscopy scanners and computerized analysis are capable of capturing and analyzing data rapidly, microscopy image data remain underutilized in research and clinical settings. One major obstacle which tends to reduce wider adoption of these new technologies throughout the clinical and scientific communities is the challenge of managing, querying, and integrating the vast amounts of data resulting from the analysis of large digital pathology datasets. This paper presents a data model, which addresses these challenges, and demonstrates its implementation in a relational database system. Context: This paper describes a data model, referred to as Pathology Analytic Imaging Standards (PAIS, and a database implementation, which are designed to support the data management and query requirements of detailed characterization of micro-anatomic morphology through many interrelated analysis pipelines on whole-slide images and tissue microarrays (TMAs. Aims: (1 Development of a data model capable of efficiently representing and storing virtual slide related image, annotation, markup, and feature information. (2 Development of a database, based on the data model, capable of supporting queries for data retrieval based on analysis and image metadata, queries for comparison of results from different analyses, and spatial queries on segmented regions, features, and classified objects. Settings and Design: The work described in this paper is motivated by the challenges associated with characterization of micro-scale features for comparative and correlative analyses involving whole-slides tissue images and TMAs. Technologies for digitizing tissues have advanced significantly in the past decade. Slide scanners are capable of producing high-magnification, high-resolution images from whole

  5. High-resolution MR imaging for dental impressions: a feasibility study.

    Science.gov (United States)

    Boldt, Julian; Rottner, Kurt; Schmitter, Marc; Hopfgartner, Andreas; Jakob, Peter; Richter, Ernst-Jürgen; Tymofiyeva, Olga

    2018-04-01

    Magnetic resonance imaging is an emerging technology in dental medicine. While low-resolution MRI has especially provided means to examine the temporomandibular joint due to its anatomic inaccessibility, it was the goal of this study to assess whether high-resolution MRI is capable of delivering a dataset sufficiently precise enough to serve as digital impression of human teeth. An informed and consenting patient in need of dental restoration with fixed partial dentures was chosen as subject. Two prepared teeth were measured using MRI and the dataset subjected to mathematical processing before Fourier transformation. After reconstruction, a 3D file was generated which was fed into an existing industry standard CAD/CAM process. A framework for a fixed dental prosthesis was digitally modeled and manufactured by laser-sintering. The fit in situ was found to be acceptable by current clinical standards, which allowed permanent placement of the fixed prosthesis. Using a clinical whole-body MR scanner with the addition of custom add-on hardware, contrast enhancement, and data post-processing, resolution and signal-to-noise ratio were sufficiently achieved to allow fabrication of a dental restoration in an acquisition time comparable to the setting time of common dental impression materials. Furthermore, the measurement was well tolerated. The herein described method can be regarded as proof of principle that MRI is a promising option for digital impressions when fixed partial dentures are required.

  6. High-resolution mechanical imaging of glioblastoma by multifrequency magnetic resonance elastography.

    Directory of Open Access Journals (Sweden)

    Kaspar-Josche Streitberger

    Full Text Available OBJECTIVE: To generate high-resolution maps of the viscoelastic properties of human brain parenchyma for presurgical quantitative assessment in glioblastoma (GB. METHODS: Twenty-two GB patients underwent routine presurgical work-up supplemented by additional multifrequency magnetic resonance elastography. Two three-dimensional viscoelastic parameter maps, magnitude |G*|, and phase angle φ of the complex shear modulus were reconstructed by inversion of full wave field data in 2-mm isotropic resolution at seven harmonic drive frequencies ranging from 30 to 60 Hz. RESULTS: Mechanical brain maps confirmed that GB are composed of stiff and soft compartments, resulting in high intratumor heterogeneity. GB could be easily differentiated from healthy reference tissue by their reduced viscous behavior quantified by φ (0.37±0.08 vs. 0.58±0.07. |G*|, which in solids more relates to the material's stiffness, was significantly reduced in GB with a mean value of 1.32±0.26 kPa compared to 1.54±0.27 kPa in healthy tissue (P = 0.001. However, some GB (5 of 22 showed increased stiffness. CONCLUSION: GB are generally less viscous and softer than healthy brain parenchyma. Unrelated to the morphology-based contrast of standard magnetic resonance imaging, elastography provides an entirely new neuroradiological marker and contrast related to the biomechanical properties of tumors.

  7. High-resolution imaging of ultracold fermions in microscopically tailored optical potentials

    International Nuclear Information System (INIS)

    Zimmermann, B; Mueller, T; Meineke, J; Esslinger, T; Moritz, H

    2011-01-01

    We report on the local probing and preparation of an ultracold Fermi gas on the length scale of one micrometer, i.e. of the order of the Fermi wavelength. The essential tool of our experimental setup is a pair of identical, high-resolution microscope objectives. One of the microscope objectives allows local imaging of the trapped Fermi gas of 6 Li atoms with a maximum resolution of 660 nm, while the other enables the generation of arbitrary optical dipole potentials on the same length scale. Employing a two-dimensional (2D) acousto-optical deflector, we demonstrate the formation of several trapping geometries, including a tightly focused single optical dipole trap, a 4x4 site 2D optical lattice and an 8 site ring lattice configuration. Furthermore, we show the ability to load and detect a small number of atoms in these trapping potentials. A site separation down to one micrometer in combination with the low mass of 6 Li results in tunneling rates that are sufficiently large for the implementation of Hubbard models with the designed geometries.

  8. High-Resolution Aeromagnetic Survey To Image Shallow Faults, Poncha Springs and Vicinity, Chaffee County, Colorado

    Science.gov (United States)

    Grauch, V.J.S.; Drenth, Benjamin J.

    2009-01-01

    High-resolution aeromagnetic data were acquired over the town of Poncha Springs and areas to the northwest to image faults, especially where they are concealed. Because this area has known hot springs, faults or fault intersections at depth can provide pathways for upward migration of geothermal fluids or concentrate fracturing that enhances permeability. Thus, mapping concealed faults provides a focus for follow-up geothermal studies. Fault interpretation was accomplished by synthesizing interpretative maps derived from several different analytical methods, along with preliminary depth estimates. Faults were interpreted along linear aeromagnetic anomalies and breaks in anomaly patterns. Many linear features correspond to topographic features, such as drainages. A few of these are inferred to be fault-related. The interpreted faults show an overall pattern of criss-crossing fault zones, some of which appear to step over where they cross. Faults mapped by geologists suggest similar crossing patterns in exposed rocks along the mountain front. In low-lying areas, interpreted faults show zones of west-northwest-, north-, and northwest-striking faults that cross ~3 km (~2 mi) west-northwest of the town of Poncha Springs. More easterly striking faults extend east from this juncture. The associated aeromagnetic anomalies are likely caused by magnetic contrasts associated with faulted sediments that are concealed less than 200 m (656 ft) below the valley floor. The faults may involve basement rocks at greater depth as well. A relatively shallow (hot springs and south of the town of Poncha Springs.

  9. MTRC compensation in high-resolution ISAR imaging via improved polar format algorithm based on ICPF

    Science.gov (United States)

    Liu, Yang; Xu, Shiyou; Chen, Zengping; Yuan, Bin

    2014-12-01

    In this paper, we present a detailed analysis on the performance degradation of inverse synthetic aperture radar (ISAR) imagery with the polar format algorithm (PFA) due to the inaccurate rotation center. And a novel algorithm is developed to estimate the rotation center for ISAR targets to overcome the degradation. In real ISAR scenarios, the real rotation center shift is usually not coincided with the gravity center of the high-resolution range profile (HRRP), due to the data-driven translational motion compensation. Because of the imprecise information of rotation center, PFA image yields model errors and severe blurring in the cross-range direction. To tackle this problem, an improved PFA based on integrated cubic phase function (ICPF) is proposed. In the method, the rotation center in the slant range is estimated firstly by ICPF, and the signal is shifted accordingly. Finally, the standard PFA algorithm can be carried out straightforwardly. With the proposed method, wide-angle ISAR imagery of non-cooperative targets can be achieved by PFA with improved focus quality. Simulation and real-data experiments confirm the effectiveness of the proposal.

  10. High resolution imaging of impacted CFRP composites with a fiber-optic laser-ultrasound scanner

    Directory of Open Access Journals (Sweden)

    Ivan Pelivanov

    2016-06-01

    Full Text Available Damage induced in polymer composites by various impacts must be evaluated to predict a component’s post-impact strength and residual lifetime, especially when impacts occur in structures related to human safety (in aircraft, for example. X-ray tomography is the conventional standard to study an internal structure with high resolution. However, it is of little use when the impacted area cannot be extracted from a structure. In addition, X-ray tomography is expensive and time-consuming. Recently, we have demonstrated that a kHz-rate laser-ultrasound (LU scanner is very efficient both for locating large defects and evaluating the material structure. Here, we show that high-quality images of damage produced by the LU scanner in impacted carbon-fiber reinforced polymer (CFRP composites are similar to those produced by X-ray tomograms; but they can be obtained with only single-sided access to the object under study. Potentially, the LU method can be applied to large components in-situ.

  11. High resolution imaging of impacted CFRP composites with a fiber-optic laser-ultrasound scanner.

    Science.gov (United States)

    Pelivanov, Ivan; Ambroziński, Łukasz; Khomenko, Anton; Koricho, Ermias G; Cloud, Gary L; Haq, Mahmoodul; O'Donnell, Matthew

    2016-06-01

    Damage induced in polymer composites by various impacts must be evaluated to predict a component's post-impact strength and residual lifetime, especially when impacts occur in structures related to human safety (in aircraft, for example). X-ray tomography is the conventional standard to study an internal structure with high resolution. However, it is of little use when the impacted area cannot be extracted from a structure. In addition, X-ray tomography is expensive and time-consuming. Recently, we have demonstrated that a kHz-rate laser-ultrasound (LU) scanner is very efficient both for locating large defects and evaluating the material structure. Here, we show that high-quality images of damage produced by the LU scanner in impacted carbon-fiber reinforced polymer (CFRP) composites are similar to those produced by X-ray tomograms; but they can be obtained with only single-sided access to the object under study. Potentially, the LU method can be applied to large components in-situ.

  12. Expressway deformation mapping using high-resolution TerraSAR-X images

    KAUST Repository

    Shi, Xuguo

    2014-01-27

    Monitoring deformation of linear infrastructures such as expressway and railway caused by natural processes or anthropogenic activities is a vital task to ensure the safety of human lives and properties. Interferometric Synthetic Aperture Radar (InSAR) has been widely recognized as an effective technology to carry out large-area surface deformation mapping. However, its application in linear infrastructure deformation monitoring has not been intensively studied till now. In this article, a modified Small BAseline Subset (SBAS) method is proposed to retrieve the deformation patterns of the expressway. In our method, only the point-like targets identified on the expressway were kept in our analysis, and two complementary subsets of interferograms were formed to better separate the signals of height error and deformation from inteferometric phase observations. We successfully applied this method with multitemporal high-resolution TerraSAR-X images to retrieve the spatialoral pattern of surface deformation along the Beian-Heihe expressway that is located in island-permafrost areas and threatened by geohazards. © 2014 Taylor & Francis.

  13. Michelson Interferometer for Global High-Resolution Thermospheric Imaging (MIGHTI): Instrument Design and Calibration

    Science.gov (United States)

    Englert, Christoph R.; Harlander, John M.; Brown, Charles M.; Marr, Kenneth D.; Miller, Ian J.; Stump, J. Eloise; Hancock, Jed; Peterson, James Q.; Kumler, Jay; Morrow, William H.; Mooney, Thomas A.; Ellis, Scott; Mende, Stephen B.; Harris, Stewart E.; Stevens, Michael H.; Makela, Jonathan J.; Harding, Brian J.; Immel, Thomas J.

    2017-10-01

    The Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument was built for launch and operation on the NASA Ionospheric Connection Explorer (ICON) mission. The instrument was designed to measure thermospheric horizontal wind velocity profiles and thermospheric temperature in altitude regions between 90 km and 300 km, during day and night. For the wind measurements it uses two perpendicular fields of view pointed at the Earth's limb, observing the Doppler shift of the atomic oxygen red and green lines at 630.0 nm and 557.7 nm wavelength. The wavelength shift is measured using field-widened, temperature compensated Doppler Asymmetric Spatial Heterodyne (DASH) spectrometers, employing low order échelle gratings operating at two different orders for the different atmospheric lines. The temperature measurement is accomplished by a multichannel photometric measurement of the spectral shape of the molecular oxygen A-band around 762 nm wavelength. For each field of view, the signals of the two oxygen lines and the A-band are detected on different regions of a single, cooled, frame transfer charge coupled device (CCD) detector. On-board calibration sources are used to periodically quantify thermal drifts, simultaneously with observing the atmosphere. The MIGHTI requirements, the resulting instrument design and the calibration are described.

  14. High-Resolution Imaging of Proteins in Human Teeth by Scanning Probe Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gruverman, A. [North Carolina State University; Wu, D. [North Carolina State University; Rodriguez, Brian J [ORNL; Kalinin, Sergei V [ORNL; Habelitz, S. [University of California, San Francisco

    2007-01-01

    High-resolution studies of dental tissues are of considerable interest for biomedical engineering and clinical applications. In this paper, we demonstrate the application of piezoresponse force microscopy (PFM) to nanoscale imaging of internal structure of human teeth by monitoring the local mechanical response to an electrical bias applied via a conductive tip. It is shown that PFM is capable of detecting dissimilar components of dental tissues, namely, proteins and calcified matrix, which have resembling morphology but different piezoelectric properties. It is demonstrated that collagen fibrils revealed in chemically treated intertubular dentin exhibit high piezoelectric activity and can be visualized in PFM with spatial resolution of 10 nm. Evidence of the presence of protein inclusions of 100-200 nm wide and several micrometers long in tooth enamel has been obtained. Furthermore, it is found that the peritubular dentin and intertubular dentin exhibit different piezoelectric behavior suggesting different concentration of collagen fibrils. The obtained results demonstrate a high potential of PFM in providing an additional insight into the structure of dental tissues. It is suggested that the PFM approach can be used to study the structure of a wide range of biological materials by monitoring their electromechanical behavior at the nanoscale.

  15. CEST ANALYSIS: AUTOMATED CHANGE DETECTION FROM VERY-HIGH-RESOLUTION REMOTE SENSING IMAGES

    Directory of Open Access Journals (Sweden)

    M. Ehlers

    2012-08-01

    was tested with high-resolution satellite images of the crisis areas of Darfur (Sudan. CEST results are compared with a number of standard algorithms for automated change detection such as image difference, image ratioe, principal component analysis, delta cue technique and post classification change detection. The new combined method shows superior results averaging between 45% and 15% improvement in accuracy.

  16. High-resolution imaging with two-axis orthogonal magneto-resistive sensor based eddy current probe

    Science.gov (United States)

    Wincheski, Buzz; Simpson, John; Seebo, Jeffery P.; Powell, Jessica

    2012-05-01

    A two-channel magneto-resistive sensor with an embedded, single-strand eddy current inducer has been fabricated and tested for applications including sensory material characterization and the analysis of intermittent contact along compression boundaries and fatigue cracks. A rapid scanning technique has also been implemented to enable high-resolution imaging of relatively large areas in modest times. Applications of the probe for high-resolution imaging of calibration artifacts and sensory materials are presented. Finite element modeling of the probe is also presented and compared with experimental measurements with good agreement.

  17. High-resolution vascular tissue characterization in mice using 55 MHz ultrasound hybrid imaging

    Science.gov (United States)

    Mahmoud, Ahmed M.; Sandoval, Cesar; Teng, Bunyen; Schnermann, Jurgen B.; Martin, Karen H.; Mustafa, S. Jamal; Mukdadi, Osama M.

    2012-01-01

    Ultrasound and Duplex ultrasonography in particular are routinely used to diagnose cardiovascular disease (CVD), which is the leading cause of morbidity and mortality worldwide. However, these techniques may not be able to characterize vascular tissue compositional changes due to CVD. This work describes an ultrasound-based hybrid imaging technique that can be used for vascular tissue characterization and the diagnosis of atherosclerosis. Ultrasound radiofrequency (RF) data were acquired and processed in time, frequency, and wavelet domains to extract six parameters including time integrated backscatter (TIB), time variance (Tvar), time entropy (TE), frequency integrated backscatter (FIB), wavelet root mean square value (Wrms), and wavelet integrated backscatter (WIB). Each parameter was used to reconstruct an image co-registered to morphological B-scan. The combined set of hybrid images were used to characterize vascular tissue in vitro and in vivo using three mouse models including control (C57BL/6), and atherosclerotic apolipoprotein E-knockout (APOE-KO) and APOE/A1 adenosine receptor double knockout (DKO) mice. The technique was tested using high-frequency ultrasound including single-element (center frequency = 55 MHz) and commercial array (center frequency = 40 MHz) systems providing superior spatial resolutions of 24 μm and 40 μm, respectively. Atherosclerotic vascular lesions in the APOE-KO mouse exhibited the highest values (contrast) of −10.11 ± 1.92 dB, −12.13 ± 2.13 dB, −7.54 ± 1.45 dB, −5.10 ± 1.06 dB, −5.25 ± 0.94 dB, and −10.23 ± 2.12 dB in TIB, Tvar, TE, FIB, Wrms, WIB hybrid images (n = 10, p ultrasound findings within a maximum error of 3.6% in lesion estimation. This study demonstrated the feasibility of a high-resolution hybrid imaging technique to diagnose atherosclerosis and characterize plaque components in mouse. In the future, it can be easily implemented on commercial ultrasound systems and eventually translated into

  18. Resolution-recovery-embedded image reconstruction for a high-resolution animal SPECT system.

    Science.gov (United States)

    Zeraatkar, Navid; Sajedi, Salar; Farahani, Mohammad Hossein; Arabi, Hossein; Sarkar, Saeed; Ghafarian, Pardis; Rahmim, Arman; Ay, Mohammad Reza

    2014-11-01

    The small-animal High-Resolution SPECT (HiReSPECT) is a dedicated dual-head gamma camera recently designed and developed in our laboratory for imaging of murine models. Each detector is composed of an array of 1.2 × 1.2 mm(2) (pitch) pixelated CsI(Na) crystals. Two position-sensitive photomultiplier tubes (H8500) are coupled to each head's crystal. In this paper, we report on a resolution-recovery-embedded image reconstruction code applicable to the system and present the experimental results achieved using different phantoms and mouse scans. Collimator-detector response functions (CDRFs) were measured via a pixel-driven method using capillary sources at finite distances from the head within the field of view (FOV). CDRFs were then fitted by independent Gaussian functions. Thereafter, linear interpolations were applied to the standard deviation (σ) values of the fitted Gaussians, yielding a continuous map of CDRF at varying distances from the head. A rotation-based maximum-likelihood expectation maximization (MLEM) method was used for reconstruction. A fast rotation algorithm was developed to rotate the image matrix according to the desired angle by means of pre-generated rotation maps. The experiments demonstrated improved resolution utilizing our resolution-recovery-embedded image reconstruction. While the full-width at half-maximum (FWHM) radial and tangential resolution measurements of the system were over 2 mm in nearly all positions within the FOV without resolution recovery, reaching around 2.5 mm in some locations, they fell below 1.8 mm everywhere within the FOV using the resolution-recovery algorithm. The noise performance of the system was also acceptable; the standard deviation of the average counts per voxel in the reconstructed images was 6.6% and 8.3% without and with resolution recovery, respectively. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  19. Imaging the Danish Chalk Group with high resolution, 3-component seismics

    Science.gov (United States)

    Kammann, J.; Rasmussen, S. L.; Nielsen, L.; Malehmir, A.; Stemmerik, L.

    2016-12-01

    The Chalk Group in the Danish Basin forms important reservoirs to hydrocarbons as well as water resources, and it has been subject to several seismic studies to determine e.g. structural elements, deposition and burial history. This study focuses on the high quality seismic response of a survey acquired with an accelerated 45 kg weight drop and 3-component MEMS-based sensors and additional wireless vertical-type sensors. The 500 m long profile was acquired during one day close to a chalk quarry and chalk cliffs of the Stevns peninsula in eastern Denmark where the well-known K-T (Cretaceous-Tertiary) boundary and different chalk lithologies are well-exposed. With this simple and fast procedure we were able to achieve deep P-wave penetration to the base of the Chalk Group at about 900 m depth. Additionally, the CMP-processed seismic image of the vertical component stands out by its high resolution. Sedimentary features are imaged in the near-surface Danian, as well as in the deeper Maastrichtian and Upper Campanian parts of the Chalk Group. Integration with borehole data suggests that changes in composition, in particular clay content, correlate with changes in reflectivity of the seismic data set. While the pure chalk in the Maastrichtian deposits shows rather low reflectivity, succession enriched in clay appear to be more reflective. The integration of the mentioned methods gives the opportunity to connect changes in facies to the elastic response of the Chalk Group in its natural environmental conditions.

  20. EUV high resolution imager on-board solar orbiter: optical design and detector performances

    Science.gov (United States)

    Halain, J. P.; Mazzoli, A.; Rochus, P.; Renotte, E.; Stockman, Y.; Berghmans, D.; BenMoussa, A.; Auchère, F.

    2017-11-01

    The EUV high resolution imager (HRI) channel of the Extreme Ultraviolet Imager (EUI) on-board Solar Orbiter will observe the solar atmospheric layers at 17.4 nm wavelength with a 200 km resolution. The HRI channel is based on a compact two mirrors off-axis design. The spectral selection is obtained by a multilayer coating deposited on the mirrors and by redundant Aluminum filters rejecting the visible and infrared light. The detector is a 2k x 2k array back-thinned silicon CMOS-APS with 10 μm pixel pitch, sensitive in the EUV wavelength range. Due to the instrument compactness and the constraints on the optical design, the channel performance is very sensitive to the manufacturing, alignments and settling errors. A trade-off between two optical layouts was therefore performed to select the final optical design and to improve the mirror mounts. The effect of diffraction by the filter mesh support and by the mirror diffusion has been included in the overall error budget. Manufacturing of mirror and mounts has started and will result in thermo-mechanical validation on the EUI instrument structural and thermal model (STM). Because of the limited channel entrance aperture and consequently the low input flux, the channel performance also relies on the detector EUV sensitivity, readout noise and dynamic range. Based on the characterization of a CMOS-APS back-side detector prototype, showing promising results, the EUI detector has been specified and is under development. These detectors will undergo a qualification program before being tested and integrated on the EUI instrument.

  1. Isotope specific resolution recovery image reconstruction in high resolution PET imaging

    OpenAIRE

    Kotasidis Fotis A.; Kotasidis Fotis A.; Angelis Georgios I.; Anton-Rodriguez Jose; Matthews Julian C.; Reader Andrew J.; Reader Andrew J.; Zaidi Habib; Zaidi Habib; Zaidi Habib

    2014-01-01

    Purpose: Measuring and incorporating a scanner specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However due to the short half life of clinically used isotopes other long lived isotopes not used in clinical practice are used to perform the PSF measurements. As such non optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction usuall...

  2. Isotope specific resolution recovery image reconstruction in high resolution PET imaging

    NARCIS (Netherlands)

    Kotasidis, Fotis A.; Angelis, Georgios I.; Anton-Rodriguez, Jose; Matthews, Julian C.; Reader, Andrew J.; Zaidi, Habib

    Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to

  3. So Many Rockets - The Road to High Resolution Imaging in X-rays

    Science.gov (United States)

    Murray, Stephen S.

    2013-01-01

    When I first begin to work on new imaging detectors for X-ray Astronomy I was at AS&E and I worked with Leon Van Speybroeck and Ed Kellogg on a sounding rocket project. We starting by using a microchannel plate image intensifier to detect X-ray photons and convert them to flashes of light that were recorded on 35 mm film frames. Simultaneously there was a 16 mm star camera taking frames so we could tell where the X-rays were coming from. I spent about 6 years working on this payload, eventually becoming the PI and evolving the detector from a film readout to an electronic readout (the crossed grid charge detector) that was the basis for the Einstein, ROSAT and Chandra High Resolution Imagers and Cameras. We had a series of about 6 or so rocket flights culminating in the 1978 flight that actually worked. We detected three photons from Sco X1, and background data from that flight allowed us to set the detector front bias voltage to minimize non-X-ray background for the Einstein HRI. Just about everything that could go wrong on those rockets did go wrong, from a switch not closing to a rocket misfire, to pointing 180 degrees off target. But we learned something each flight and kept coming back to try again. The worse thing for me was having to stay up all night at White Sands in a small darkroom where I could avoid the night crawlers and scorpions that frightened me to death. Not to mention the daredevil helicopter pilots who flew us to the recovery site hugging the ground at top speed all the way there! None-the-less, in the end we succeeded in our goals, and there is nothing so exciting as watching your payload being launched at night (even it did mean sneaking out from the bunker to do it!). Thanks to NASA and the US Navy's White Sands USS Desert Ship (LLS-1; Land Locked Ship - 1) for all the support.

  4. Clinical Significance of Wall Changes After Recanalization Therapy in Acute Stroke: High-Resolution Vessel Wall Imaging.

    Science.gov (United States)

    Seo, Woo-Keun; Oh, Kyungmi; Suh, Sang-Il; Seol, Hae Young

    2017-04-01

    Owing to the excellent recanalization rate of endovascular treatment, new outcome predictors are required for patients with acute stroke, who have sufficient recanalization. In this study, the effects of recanalization therapy on occluded arteries in patients with acute stroke were investigated using high-resolution vessel wall imaging. Twenty-nine patients with stroke were included in the study. High-resolution vessel wall imaging was performed on patients with acute stroke and adequate postrecanalization results. We characterized the postrecanalization arterial wall changes as concentric enhancements and plaques and examined the associations of the postrecanalization changes with procedural factors and neurological outcomes. The most frequent high-resolution vessel wall imaging finding was concentric enhancement, which was associated with thrombectomy procedural factors such as the number of procedures and the type of device. Concentric enhancements were associated with hemorrhagic transformation, whereas plaque was not associated with procedural details. The use of high-resolution vessel wall imaging after successful recanalization can provide information about postrecanalization arterial wall changes and clinical outcomes. © 2017 American Heart Association, Inc.

  5. Detecting and locating light atoms from high-resolution STEM images : The quest for a single optimal design

    NARCIS (Netherlands)

    Gonnissen, J; De Backer, A; den Dekker, A.J.; Sijbers, J.; Van Aert, S.

    2016-01-01

    In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of

  6. Using high-resolution radar images to determine vegetation cover for soil erosion assessments.

    Science.gov (United States)

    Bargiel, D; Herrmann, S; Jadczyszyn, J

    2013-07-30

    Healthy soils are crucial for human well-being. Because soils are threatened worldwide, politicians recognize the need for soil protection. For example, the European Commission has launched the Thematic Strategy for Soil Protection, which requests the European member states to identify high risk areas for soil degradation. Most states use the Universal Soil Loss Equation (USLE) to assess soil erosion risk at the national scale. The USLE includes different factors, one of them is the vegetation cover and management factor (C factor). Modern satellite-based radar sensors now provide highly accurate vegetation cover data, enabling opportunities to improve the accuracy of the C factor. The presented study proves the suitability for C factor determination based on a multi-temporal classification of high-resolution radar images. Further USLE factors were derived from existing data sources (meteorological data, soil maps, digital elevation model) to conduct an USLE-based soil erosion assessment. The resulting map illustrates a qualitative assessment for soil erosion risk within a plot of about 7*12 km in an agricultural region in Poland that is very susceptible to soil erosion processes. A high erosion risk of more than 10 tonnes per ha and year was assessed to occur on 13.6% (646 ha) of the agricultural areas within the investigated plot. Further 7.8% (372 ha) of agricultural land is threaten by a medium risk of 5-10 tonnes per ha and year. Such a spatial information about areas of high or medium soil erosion risk are crucial for the development of strategies for the protection of soils. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. In vivo skin moisturizing measurement by high-resolution 3 Tesla magnetic resonance imaging.

    Science.gov (United States)

    Mesrar, J; Ognard, J; Garetier, M; Chechin, D; Misery, L; Ben Salem, D

    2017-08-01

    Magnetic resonance imaging (MRI) is rarely used for the exploration of skin, even if studies have validated both feasibility of skin MRI and its interest for anatomical, physiological, and biochemical study of the skin. The purpose of this study is to explore moisturizing of the different skin layers using 3-T scan. An MRI of the heel's skin was performed using a 23 mm coil diameter on a 3T scan with a FFE (Fast Field Echo) 3D T1-weighted sequence and a TSE (Turbo Spin Echo) calculation T2-weighted sequence (pixels size of respectively 60 and 70 μm). This study was conducted on 35 healthy volunteers, who were scanned before applying moisturizer topic and 1 h after applying it. Region of interest in the stratum corneum, the epidermis and the dermis were generated on the T2 mapping. The thickness of each layer was measured. The T1 sequence allowed accurate cross-examination repositioning to ensure the comparability of the measurements. Among the 35 cases, two were excluded from the analysis because of movement artifacts. Measurements before and after moisturizer topic application displayed a T2 increase of 48.94% (P < 0.0001) in the stratum corneum and of 5.45% (P < 0.0001) in the epidermis yet without significant difference in the dermis. There was no significant link between the thickness of the stratum corneum and the T2 increase. However, there was a strong correlation between the thickness of the stratum corneum and the thickness of the epidermis (P < 0.001; rhô=0.72). High-resolution MRI allows fine exploration of anatomical and physiological properties of the skin and can further be used to extend the studies of skin hydration. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. High-resolution MR imaging of periarterial edema associated with biological inflammation in spontaneous carotid dissection

    Energy Technology Data Exchange (ETDEWEB)

    Naggara, Olivier; Marsico, Rodolpho; Meder, Jean-Francois; Oppenheim, Catherine [Paris-Descartes University, Department of Neuroradiology, Paris (France); Touze, Emmanuel; Mas, Jean-Louis [Paris-Descartes University, Department of Neurology, Paris (France); Leclerc, Xavier; Pruvo, Jean-Pierre [University Hospital Roger Salengro, Department of Neuroradiology, Lille (France); Nguyen, Thanh [Boston University Medical Center, Department of Neurology, Neurosurgery, and Radiology, Boston, MA (United States)

    2009-09-15

    It has been suggested that spontaneous cervical carotid artery dissection (sCAD) may result from arterial inflammation. Periarterial edema (PAE), occasionally described in the vicinity of the mural hematoma in patients with sCAD, may support this hypothesis. Using cervical high-resolution magnetic resonance imaging, three readers, blinded to the mechanism of carotid artery dissection, searched for PAE, defined as periarterial T2-hyperintensity and T1-hypointensity, in 29 consecutive CAD patients categorized as spontaneous CAD (sCAD, n = 18) or traumatic CAD (tCAD, n = 11; i.e., major head or neck trauma within 2 weeks before the clinical onset). The relationships between PAE, inflammatory biological markers, history of infection and CAD mechanism were explored. Multiple CADs (n = 8) were found only in sCAD patients. Compared with tCAD, patients with sCAD were more likely to have a recent history of infection (OR = 12.5 [{sub 95%}CI = 1.3-119], p = 0.03), PAE (83% vs. 27%; OR = 13.3 [{sub 95%}CI = 2.2-82.0], p = 0.005) and to have elevated CRP (OR = 6.1 [{sub 95%}CI = 1.2-32.1], p = 0.0002) or ESR (OR = 8.8 [{sub 95%}CI = 1.5-50.1], p = 0.002) values. Interobserver agreement was 0.84 or higher for PAE identification. sCAD was associated with PAE and biological inflammation. Our results support the hypothesis of an underlying arterial inflammation in sCAD. (orig.)

  9. High-resolution MR imaging of periarterial edema associated with biological inflammation in spontaneous carotid dissection

    International Nuclear Information System (INIS)

    Naggara, Olivier; Marsico, Rodolpho; Meder, Jean-Francois; Oppenheim, Catherine; Touze, Emmanuel; Mas, Jean-Louis; Leclerc, Xavier; Pruvo, Jean-Pierre; Nguyen, Thanh

    2009-01-01

    It has been suggested that spontaneous cervical carotid artery dissection (sCAD) may result from arterial inflammation. Periarterial edema (PAE), occasionally described in the vicinity of the mural hematoma in patients with sCAD, may support this hypothesis. Using cervical high-resolution magnetic resonance imaging, three readers, blinded to the mechanism of carotid artery dissection, searched for PAE, defined as periarterial T2-hyperintensity and T1-hypointensity, in 29 consecutive CAD patients categorized as spontaneous CAD (sCAD, n = 18) or traumatic CAD (tCAD, n = 11; i.e., major head or neck trauma within 2 weeks before the clinical onset). The relationships between PAE, inflammatory biological markers, history of infection and CAD mechanism were explored. Multiple CADs (n = 8) were found only in sCAD patients. Compared with tCAD, patients with sCAD were more likely to have a recent history of infection (OR = 12.5 [ 95% CI = 1.3-119], p = 0.03), PAE (83% vs. 27%; OR = 13.3 [ 95% CI = 2.2-82.0], p = 0.005) and to have elevated CRP (OR = 6.1 [ 95% CI = 1.2-32.1], p = 0.0002) or ESR (OR = 8.8 [ 95% CI = 1.5-50.1], p = 0.002) values. Interobserver agreement was 0.84 or higher for PAE identification. sCAD was associated with PAE and biological inflammation. Our results support the hypothesis of an underlying arterial inflammation in sCAD. (orig.)

  10. A three-axis high-resolution capacitive tactile imager system based on floating comb electrodes

    International Nuclear Information System (INIS)

    Surapaneni, R; Guo, Q; Xie, Y; Young, D J; Mastrangelo, C H

    2013-01-01

    We present the design, fabrication and testing of a high-resolution 169-sensing cell capacitive flexible tactile imager (FTI) for normal and shear stress measurement as an auxiliary sensor for robotic grippers and gait analysis. The FTI consists of a flexible high-density array of normal stress and two-dimensional shear stress sensors fabricated using microelectromechanical systems (MEMS) and flexible printed circuit board (FPCB) techniques. The drive/sense lines of the FTI are realized using FPCB whereas the floating electrodes (Au) are patterned on a compressible PDMS layer spin coated on the FPCB layer. The use of unconnected floating electrodes significantly improves the reliability of traditional quad-electrode contact sensing devices by eliminating the need for patterning electrical wiring on PDMS. When placed at the heel of a boot, this FTI senses the position and motion of the line of contact with the ground. Normal stress readouts are obtained from the net capacitance of the cell and the shear-sense direction is determined by the amount of asymmetric overlap of the floating combs with respect to the bottom electrodes. The FTI is characterized using a high-speed switched-capacitor circuit with a 12-bit resolution at full frame rates of 100 Hz (∼0.8 Mb s −1 ) capable of resolving a displacement as low as 60 µm. The FTI and the readout circuitry contribute to a noise/interference level of 5 mV and the sensitivity of normal and shear stress for the FTI is 0.38 MPa −1 and 79.5 GPa −1 respectively. (paper)

  11. High-resolution vascular tissue characterization in mice using 55MHz ultrasound hybrid imaging.

    Science.gov (United States)

    Mahmoud, Ahmed M; Sandoval, Cesar; Teng, Bunyen; Schnermann, Jurgen B; Martin, Karen H; Mustafa, S Jamal; Mukdadi, Osama M

    2013-03-01

    error of 3.6% in lesion estimation. This study demonstrated the feasibility of a high-resolution hybrid imaging technique to diagnose atherosclerosis and characterize plaque components in mouse. In the future, it can be easily implemented on commercial ultrasound systems and eventually translated into clinics as a screening tool for atherosclerosis and the assessment of vulnerable plaques. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. High-Resolution T2-Weighted Abdominal Magnetic Resonance Imaging Using Respiratory Triggering: Impact of Butylscopolamine on Image Quality

    International Nuclear Information System (INIS)

    Wagner, M.; Klessen, C.; Rief, M.; Elgeti, T.; Taupitz, M.; Hamm, B.; Asbach, P.

    2008-01-01

    Background: Respiratory triggering allows the acquisition of high-resolution magnetic resonance (MR) images of the upper abdomen. However, the depiction of organs close to the gastrointestinal tract can be considerably impaired by ghosting artifacts and blurring caused by bowel peristalsis. Purpose: To evaluate the effect of gastrointestinal motion suppression by intramuscular butylscopolamine administration on the image quality of a respiratory-triggered T2-weighted turbo spin-echo (T2w TSE) sequence of the upper abdomen. Material and Methods: Images of 46 patients were retrospectively analyzed. Twenty-four patients had received intramuscular injection of 40 mg butylscopolamine immediately before MR imaging. Fourteen of the 24 patients in the butylscopolamine group underwent repeat imaging after a mean of 29 min. Quantitative analysis of the ghosting artifacts was done by measuring signal intensities in regions of interest placed in air anterior to the patient. In addition, image quality was assessed qualitatively by two radiologists by consensus. Results: Spasmolytic medication with butylscopolamine reduced ghosting artifacts and significantly improved image quality of the respiratory-triggered T2w TSE sequence. The most pronounced effect of butylscopolamine administration on image quality was found for the pancreas and the left hepatic lobe. The rate of examinations with excellent or good depiction of the pancreas and the left hepatic lobe in the group without premedication and in the butylscopolamine group was 55% vs. 96% (pancreatic head), 35% vs. 88% (pancreatic body), 43% vs. 96% (pancreatic tail), and 45% vs. 83% (left hepatic lobe), respectively. Regarding the duration of the effect of intramuscular butylscopolamine, repeat imaging after a mean of 29 min did not result in a significant deterioration of image quality. Conclusion: Intramuscular butylscopolamine administration significantly improves image quality of respiratory-triggered T2-weighted abdominal

  13. High-Resolution T2-Weighted Abdominal Magnetic Resonance Imaging Using Respiratory Triggering: Impact of Butylscopolamine on Image Quality

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, M.; Klessen, C.; Rief, M.; Elgeti, T.; Taupitz, M.; Hamm, B.; Asbach, P. (Dept. of Radiology, Charite - Universitaetsmedizin Berlin, Berlin (DE))

    2008-05-15

    Background: Respiratory triggering allows the acquisition of high-resolution magnetic resonance (MR) images of the upper abdomen. However, the depiction of organs close to the gastrointestinal tract can be considerably impaired by ghosting artifacts and blurring caused by bowel peristalsis. Purpose: To evaluate the effect of gastrointestinal motion suppression by intramuscular butylscopolamine administration on the image quality of a respiratory-triggered T2-weighted turbo spin-echo (T2w TSE) sequence of the upper abdomen. Material and Methods: Images of 46 patients were retrospectively analyzed. Twenty-four patients had received intramuscular injection of 40 mg butylscopolamine immediately before MR imaging. Fourteen of the 24 patients in the butylscopolamine group underwent repeat imaging after a mean of 29 min. Quantitative analysis of the ghosting artifacts was done by measuring signal intensities in regions of interest placed in air anterior to the patient. In addition, image quality was assessed qualitatively by two radiologists by consensus. Results: Spasmolytic medication with butylscopolamine reduced ghosting artifacts and significantly improved image quality of the respiratory-triggered T2w TSE sequence. The most pronounced effect of butylscopolamine administration on image quality was found for the pancreas and the left hepatic lobe. The rate of examinations with excellent or good depiction of the pancreas and the left hepatic lobe in the group without premedication and in the butylscopolamine group was 55% vs. 96% (pancreatic head), 35% vs. 88% (pancreatic body), 43% vs. 96% (pancreatic tail), and 45% vs. 83% (left hepatic lobe), respectively. Regarding the duration of the effect of intramuscular butylscopolamine, repeat imaging after a mean of 29 min did not result in a significant deterioration of image quality. Conclusion: Intramuscular butylscopolamine administration significantly improves image quality of respiratory-triggered T2-weighted abdominal

  14. A high resolution IR/visible imaging system for the W7-X limiter

    Energy Technology Data Exchange (ETDEWEB)

    Wurden, G. A., E-mail: wurden@lanl.gov; Dunn, J. P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Stephey, L. A. [University of Wisconsin, Madison, Wisconsin 53706 (United States); Biedermann, C.; Jakubowski, M. W.; Gamradt, M. [Max Planck Institut für Plasma Physik, Wendelsteinstrasse 1, 17491 Greifswald (Germany)

    2016-11-15

    A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboard graphite limiters. The radial line of sight, through a large diameter (184 mm clear aperture) uncoated sapphire window, couples a direct viewing 1344 × 784 pixel FLIR SC8303HD camera. A germanium beam-splitter sends visible light to a 1024 × 1024 pixel Allied Vision Technologies Prosilica GX1050 color camera. Both achieve sub-millimeter resolution on the 161 mm wide, inertially cooled, segmented graphite tiles. The IR and visible cameras are controlled via optical fibers over full Camera Link and dual GigE Ethernet (2 Gbit/s data rates) interfaces, respectively. While they are mounted outside the cryostat at a distance of 3.2 m from the limiter, they are close to a large magnetic trim coil and require soft iron shielding. We have taken IR data at 125 Hz to 1.25 kHz frame rates and seen that surface temperature increases in excess of 350 °C, especially on leading edges or defect hot spots. The IR camera sees heat-load stripe patterns on the limiter and has been used to infer limiter power fluxes (∼1–4.5 MW/m{sup 2}), during the ECRH heating phase. IR images have also been used calorimetrically between shots to measure equilibrated bulk tile temperature, and hence tile energy inputs (in the range of 30 kJ/tile with 0.6 MW, 6 s heating pulses). Small UFO’s can be seen and tracked by the FLIR camera in some discharges. The calibrated visible color camera (100 Hz frame rate) has also been equipped with narrow band C-III and H-alpha filters, to compare with other diagnostics, and is used for absolute particle flux determination from the limiter surface. Sometimes, but not always, hot-spots in the IR are also seen to be bright in C-III light.

  15. A high resolution IR/visible imaging system for the W7-X limiter

    International Nuclear Information System (INIS)

    Wurden, G. A.; Dunn, J. P.; Stephey, L. A.; Biedermann, C.; Jakubowski, M. W.; Gamradt, M.

    2016-01-01

    A high-resolution imaging system, consisting of megapixel mid-IR and visible cameras along the same line of sight, has been prepared for the new W7-X stellarator and was operated during Operational Period 1.1 to view one of the five inboard graphite limiters. The radial line of sight, through a large diameter (184 mm clear aperture) uncoated sapphire window, couples a direct viewing 1344 × 784 pixel FLIR SC8303HD camera. A germanium beam-splitter sends visible light to a 1024 × 1024 pixel Allied Vision Technologies Prosilica GX1050 color camera. Both achieve sub-millimeter resolution on the 161 mm wide, inertially cooled, segmented graphite tiles. The IR and visible cameras are controlled via optical fibers over full Camera Link and dual GigE Ethernet (2 Gbit/s data rates) interfaces, respectively. While they are mounted outside the cryostat at a distance of 3.2 m from the limiter, they are close to a large magnetic trim coil and require soft iron shielding. We have taken IR data at 125 Hz to 1.25 kHz frame rates and seen that surface temperature increases in excess of 350 °C, especially on leading edges or defect hot spots. The IR camera sees heat-load stripe patterns on the limiter and has been used to infer limiter power fluxes (∼1–4.5 MW/m 2 ), during the ECRH heating phase. IR images have also been used calorimetrically between shots to measure equilibrated bulk tile temperature, and hence tile energy inputs (in the range of 30 kJ/tile with 0.6 MW, 6 s heating pulses). Small UFO’s can be seen and tracked by the FLIR camera in some discharges. The calibrated visible color camera (100 Hz frame rate) has also been equipped with narrow band C-III and H-alpha filters, to compare with other diagnostics, and is used for absolute particle flux determination from the limiter surface. Sometimes, but not always, hot-spots in the IR are also seen to be bright in C-III light.

  16. Masterpieces unmasked: New high-resolution infrared cameras produce rich, detailed images of artwork, and create new controversies

    CERN Multimedia

    Marshall, J

    2002-01-01

    Luca Pezzati is a physicist who heads a group called Art Diagnostics, which is a part of the Opificio delle Pietre Dure, an institute devoted to the research and conservation of artworks in Italy. Pezzati and his group use high-resolution infrared scanning device to produce colour images of what lies below the surface of paintings. Their scanner is able to produce the best-known quality of images without harming the painting under examination (1 page).

  17. Mechanism of high-resolution STM/AFM imaging with functionalized tips

    Czech Academy of Sciences Publication Activity Database

    Hapala, Prokop; Kichin, G.; Wagner, C.; Tautz, F.S.; Temirov, R.; Jelínek, Pavel

    2014-01-01

    Roč. 90, č. 8 (2014), "085421-1"-"085421-9" ISSN 1098-0121 R&D Projects: GA ČR(CZ) GC14-16963J Grant - others:AVČR(CZ) M100101207 Institutional support: RVO:68378271 Keywords : AFM * STM * high resolution Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.736, year: 2014

  18. Study of Fish Response Using Particle Image Velocimetry and High-Speed, High-Resolution Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Zhiqun; Richmond, Marshall C.; Guensch, Gregory R.; Mueller, Robert P.

    2004-10-23

    Existing literature of previous particle image velocimetry (PIV) studies of fish swimming has been reviewed. Historically, most of the studies focused on the performance evaluation of freely swimming fish. Technological advances over the last decade, especially the development of digital particle image velocimetry (DPIV) technique, make possible more accurate, quantitative descriptions of the flow patterns adjacent to the fish and in the wake behind the fins and tail, which are imperative to decode the mechanisms of drag reduction and propulsive efficiency. For flows generated by different organisms, the related scales and flow regimes vary significantly. For small Reynolds numbers, viscosity dominates; for very high Reynolds numbers, inertia dominates, and three-dimensional complexity occurs. The majority of previous investigations dealt with the lower end of Reynolds number range. The fish of our interest, such as rainbow trout and spring and fall chinook salmon, fall into the middle range, in which neither viscosity nor inertia is negligible, and three-dimensionality has yet to dominate. Feasibility tests have proven the applicability of PIV to flows around fish. These tests have shown unsteady vortex shedding in the wake, high vorticity region and high stress region, with the highest in the pectoral area. This evident supports the observations by Nietzel et al. (2000) and Deng et al. (2004) that the operculum are most vulnerable to damage from the turbulent shear flow, because they are easily pried open, and the large vorticity and shear stress can lift and tear off scales, rupture or dislodge eyes, and damage gills. In addition, the unsteady behavior of the vortex shedding in the wake implies that injury to fish by the instantaneous flow structures would likely be much higher than the injury level estimated using the average values of the dynamics parameters. Based on existing literature, our technological capability, and relevance and practicability to

  19. High-resolution MR imaging of the carpal tunnel and the wrist. Application of a 5-cm surface coil

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, J.; Bleschkowski, A.; Tempka, A.; Felix, R. [Medical Faculty of the Humboldt Univ., Berlin (Germany). Dept. of Radiology

    2000-07-01

    In order to make a comparative analysis of transversal tomograms obtained by high-resolution MR imaging with frozen cross-sections of an anatomical forearm specimen, twenty-two healthy volunteers were also examined using the same coil system to test for a range of possible clinical applications and for the depiction of morphological and morphometrical values of normal anatomy in vivo. MR images of the carpal tunnel of 22 healthy volunteers were obtained with a 1.5-T whole-body system with a 5-cm surface coil. Measurements were recorded with a field-of-view between 50x50 mm{sup 2} and 60x60 mm{sup 2} in a 256x256 pixel matrix for the T1 sequence. A slice thickness of 2 mm was used. The images were acquired using a T1-weighted SE sequence (TR/TE 500/38 ms) and a T2-weighted SE sequence (TR/TE 2000/70 ms). Additionally, a formalin-fixed anatomical forearm specimen was imaged for anatomic correlation. The imaged transversal cross-section levels in the specimen were subsequently freeze-sectioned. The anatomical structures of the MR findings were identified and compared with the macroscopical sections of the specimen. Based on the good depiction of details at this coil system with a pixel size in T1 of 0.195x0.195 mm, high-resolution MR imaging enabled identification of the interior structures of the carpal tunnel, as well as delineation of connective tissue. The clinical value of high-resolution MR includes the diagnosis of carpal tunnel syndrome and inflammatory disorders of the wrist. Our results support the feasibility of high-resolution MR imaging of the carpal tunnel and the wrist using small surface coils.

  20. High-resolution MR imaging of the carpal tunnel and the wrist. Application of a 5-cm surface coil

    International Nuclear Information System (INIS)

    Maurer, J.; Bleschkowski, A.; Tempka, A.; Felix, R.

    2000-01-01

    In order to make a comparative analysis of transversal tomograms obtained by high-resolution MR imaging with frozen cross-sections of an anatomical forearm specimen, twenty-two healthy volunteers were also examined using the same coil system to test for a range of possible clinical applications and for the depiction of morphological and morphometrical values of normal anatomy in vivo. MR images of the carpal tunnel of 22 healthy volunteers were obtained with a 1.5-T whole-body system with a 5-cm surface coil. Measurements were recorded with a field-of-view between 50x50 mm 2 and 60x60 mm 2 in a 256x256 pixel matrix for the T1 sequence. A slice thickness of 2 mm was used. The images were acquired using a T1-weighted SE sequence (TR/TE 500/38 ms) and a T2-weighted SE sequence (TR/TE 2000/70 ms). Additionally, a formalin-fixed anatomical forearm specimen was imaged for anatomic correlation. The imaged transversal cross-section levels in the specimen were subsequently freeze-sectioned. The anatomical structures of the MR findings were identified and compared with the macroscopical sections of the specimen. Based on the good depiction of details at this coil system with a pixel size in T1 of 0.195x0.195 mm, high-resolution MR imaging enabled identification of the interior structures of the carpal tunnel, as well as delineation of connective tissue. The clinical value of high-resolution MR includes the diagnosis of carpal tunnel syndrome and inflammatory disorders of the wrist. Our results support the feasibility of high-resolution MR imaging of the carpal tunnel and the wrist using small surface coils

  1. Inshore ship detection using high-resolution synthetic aperture radar images based on maximally stable extremal region

    Science.gov (United States)

    Wang, Qingping; Zhu, Hong; Wu, Weiwei; Zhao, Hongyu; Yuan, Naichang

    2015-01-01

    We present a method for detecting inshore ships using high-resolution synthetic aperture radar (SAR) images. The method first applies preprocessing steps to obtain the solving region of an SAR image, suitable for the berthing rules. Then the ship candidates are extracted based on a maximally stable extremal region detector, while ship detection is applied using an improved constant false alarm rate (CFAR) detector. Finally, based on discrimination processing, false alarms are removed according to compactness, therefore the ultimate detection result is obtained without interference from strong terrestrial clutter or man-made objects. Experimental results show that this method could achieve effective detection of ships in harbors using high-resolution SAR images. This method can reduce the required computation time by 99.7%, compared with the traditional CFAR method.

  2. A new simple and cheap, high-resolution planar optode imaging system: Application to oxgen and pH sensing

    DEFF Research Database (Denmark)

    Larsen, Morten; Borisov, Sergey M.; Gunwald, Björn

    2011-01-01

    A simple, high resolution colormetric planar optode imaging approach is presented. The approach is simple and inexpensive yet versatile, and can be used to study the two-dimensional distribution and dynamics of a range of analytes. The imaging approach utilizes the inbuilt color filter of standard...... commercial digital single lens reflex cameras to simultaneously record different colors (red, green, and blue) of luminophore emission light using only one excitation light source. Using the ratio between the intensity of the different colors recorded in a single image analyte concentrations can...... be calculated. The robustness of the approach is documented by obtaining high resolution data of O2 and pH distributions in marine sediments using easy synthesizable sensors. The sensors rely on the platinum(II)octaethylporphyrin (PtOEP) and lipophilic 8-Hydroxy-1,3,6-pyrenetrisulfonic acid trisodium (HPTS...

  3. Detection of Crater Rims by Image Analysis in Very High Resolution Images of Mars, Mercury and the Moon

    Science.gov (United States)

    Pina, P.; Marques, J. S.; Bandeira, L.

    2013-12-01

    The adaptive nature of automated crater detection algorithms permits achieving a high level of autonomous detections in different surfaces and consequently becoming an important tool in the update of crater catalogues. Nevertheless, the available approaches assume all craters as circular and only provide as output the radius and location of each crater. However, the delineation of impact craters following the local variability of the rims is also important to, among others, evaluate their degree of degradation or preservation, namely those studies related to ancient climate analysis. This contour determination is normally prepared in a manual way but can advantageously be done by image analysis methods, eliminating subjectivity and allowing large scale delineations. We have recently proposed a pair of independent approaches to tackle with this problem, one based on processing the crater image in polar coordinates [1], the other using morphological operators [2], which achieved a good degree of success on very high resolution images from Mars [3-4], but where enough room for improvement was still available. Thus, the integration of both approaches into a single one, suppressing the individual drawbacks of the previous approaches, permitted to strength the detection procedure. We describe now the novel sequence of processing that we have built and test it intensively in a wider variety of planetary surfaces, namely, those of Mars, Mercury and the Moon, using the very high resolution images provided by HiRISE, MDIS and LROC cameras. The automated delineations of the craters are compared to a ground-truth reference (manually delineated contours), so a quantitative evaluation can be performed; on a dataset constituted by more than one thousand impact craters we have obtained a global high delineation rate. The breakdown by crater size on each surface is performed. The whole processing procedure works on raster images and also delivers the output in the same image format

  4. MSCT versus CBCT: evaluation of high-resolution acquisition modes for dento-maxillary and skull-base imaging

    Energy Technology Data Exchange (ETDEWEB)

    Dillenseger, Jean-Philippe; Goetz, Christian [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Universite de Strasbourg, Icube, equipe MMB, CNRS, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Matern, Jean-Francois [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Gros, Catherine-Isabelle; Bornert, Fabien [Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Universite de Strasbourg, Faculte de Chirurgie Dentaire, Strasbourg (France); Le Minor, Jean-Marie [Universite de Strasbourg, Icube, equipe MMB, CNRS, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Universite de Strasbourg, Institut d' Anatomie Normale, Strasbourg (France); Constantinesco, Andre [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Choquet, Philippe [Hopitaux Universitaires de Strasbourg, Imagerie Preclinique-UF6237, Pole d' imagerie, Strasbourg (France); Universite de Strasbourg, Icube, equipe MMB, CNRS, Strasbourg (France); Universite de Strasbourg, Federation de Medecine Translationnelle de Strasbourg, Faculte de Medecine, Strasbourg (France); Hopital de Hautepierre, Imagerie Preclinique, Biophysique et Medecine Nucleaire, Strasbourg Cedex (France)

    2014-09-24

    Our aim was to conduct a quantitative and qualitative evaluation of high-resolution skull-bone imaging for dentistry and otolaryngology using different architectures of recent X-ray computed tomography systems. Three multi-slice computed tomography (MSCT) systems and one Cone-beam computed tomography (CBCT) system were used in this study. All apparatuses were tested with installed acquisition modes and proprietary reconstruction software enabling high-resolution bone imaging. Quantitative analyses were performed with small fields of view with the preclinical vmCT phantom, which permits to measure spatial resolution, geometrical accuracy, linearity and homogeneity. Ten operators performed visual qualitative analyses on the vmCT phantom images, and on dry human skull images. Quantitative analysis showed no significant differences between protocols in terms of linearity and geometric accuracy. All MSCT systems present a better homogeneity than the CBCT. Both quantitative and visual analyses demonstrate that CBCT acquisitions are not better than the collimated helical MSCT mode. Our results demonstrate that current high-resolution MSCT protocols could exceed the performance of a previous generation CBCT system for spatial resolution and image homogeneity. (orig.)

  5. High-Resolution Field-Of Widening in Human Eye Retina Imaging - Oral Paper

    Science.gov (United States)

    Dubinin, Alexander V.; Cherezova, Tatyana Yu.; Kudryashov, Alexey V.

    2008-01-01

    In this paper we investigate methods of widening high resolution area in fundus cameras equipped with adaptive optics. We first considered average phase correction method. It was found out that this method leads to isoplanatic patch increasing but residual error of correction between the reference sources increases. We also investigated the performance of an adaptive system with five reference sources and two correctors. For optimal corrector and reference sources positions we obtained approximately two times enlargement of isoplanatic patch area.

  6. Principles and simulations of high-resolution STM imaging with a flexible tip apex

    Czech Academy of Sciences Publication Activity Database

    Krejčí, Ondřej; Hapala, Prokop; Ondráček, Martin; Jelínek, Pavel

    2017-01-01

    Roč. 95, č. 4 (2017), 1-9, č. článku 045407. ISSN 2469-9950 R&D Projects: GA ČR(CZ) GC14-16963J Institutional support: RVO:68378271 Keywords : STM * AFM * high-resolution Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.836, year: 2016

  7. Definition of pertinent parameters for the evaluation of articular cartilage repair tissue with high-resolution magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Marlovits, Stefan E-mail: stefan.marlovits@akh-wien.ac.at; Striessnig, Gabriele; Resinger, Christoph T.; Aldrian, Silke M.; Vecsei, Vilmos; Imhof, Herwig; Trattnig, Siegfried

    2004-12-01

    To evaluate articular cartilage repair tissue after biological cartilage repair, we propose a new technique of non-invasive, high-resolution magnetic resonance imaging (MRI) and define a new classification system. For the definition of pertinent variables the repair tissue of 45 patients treated with three different techniques for cartilage repair (microfracture, autologous osteochondral transplantation, and autologous chondrocyte transplantation) was analyzed 6 and 12 months after the procedure. High-resolution imaging was obtained with a surface phased array coil placed over the knee compartment of interest and adapted sequences were used on a 1 T MRI scanner. The analysis of the repair tissue included the definition and rating of nine pertinent variables: the degree of filling of the defect, the integration to the border zone, the description of the surface and structure, the signal intensity, the status of the subchondral lamina and subchondral bone, the appearance of adhesions and the presence of synovitis. High-resolution MRI, using a surface phased array coil and specific sequences, can be used on every standard 1 or 1.5 T MRI scanner according to the in-house standard protocols for knee imaging in patients who have had cartilage repair procedures without substantially prolonging the total imaging time. The new classification and grading system allows a subtle description and suitable assessment of the articular cartilage repair tissue.

  8. of Hypoxia-Inducible Factor-1α Activity by the Fusion of High-Resolution SPECT and Morphological Imaging Tests

    Directory of Open Access Journals (Sweden)

    Hirofumi Fujii

    2012-01-01

    Full Text Available Purpose. We aimed to clearly visualize heterogeneous distribution of hypoxia-inducible factor 1α (HIF activity in tumor tissues in vivo. Methods. We synthesized of 125I-IPOS, a 125I labeled chimeric protein probe, that would visualize HIF activity. The biodistribution of 125I-IPOS in FM3A tumor-bearing mice was evaluated. Then, the intratumoral localization of this probe was observed by autoradiography, and it was compared with histopathological findings. The distribution of 125I-IPOS in tumors was imaged by a small animal SPECT/CT scanner. The obtained in vivo SPECT-CT fusion images were compared with ex vivo images of excised tumors. Fusion imaging with MRI was also examined. Results. 125I-IPOS well accumulated in FM3A tumors. The intratumoral distribution of 125I-IPOS by autoradiography was quite heterogeneous, and it partially overlapped with that of pimonidazole. High-resolution SPECT-CT fusion images successfully demonstrated the heterogeneity of 125I-IPOS distribution inside tumors. SPECT-MRI fusion images could give more detailed information about the intratumoral distribution of 125I-IPOS. Conclusion. High-resolution SPECT images successfully demonstrated heterogeneous intratumoral distribution of 125I-IPOS. SPECT-CT fusion images, more favorably SPECT-MRI fusion images, would be useful to understand the features of heterogeneous intratumoral expression of HIF activity in vivo.

  9. Diagnosis of intraductal spread of breast cancer by high-resolution MR imaging. Correlation between MR imaging and pathohistological findings

    Energy Technology Data Exchange (ETDEWEB)

    Date, Shuji [Hiroshima City Hospital (Japan)

    1998-04-01

    The main purpose of this study was to investigate pathohistological factors that affect the MR findings of intraductal spread (IDS) of breast cancer. The subjects of the present study were 42 breast cancer patients who were examined by MR imaging. Fat-suppressed high-resolution T1-weighted spin-echo images (350/13/1 (TR/TE/excitations), 16-cm FOV, 5-mm section thickness, and 512 x 256 matrix) were obtained one minute after the intravenous administration of Gd-DTPA. In this protocol, contrast determination time was 1 min 48 sec. Of the 42 cases, IDS was found to be located more than 1 cm from the primary focus in 22 cases (52%). Rates of sensitivity, specificity and accuracy of MR imaging for the detection of IDS were 82%, 80%, and 81%, respectively. The probable cause of misdiagnosis was parenchymal enhancement due to severe fibrocystic disease and normal menstrual cycle. In 21 of 42 cases, the MR findings were precisely correlated with the pathohistologic findings of almost the same cross-section. The MR findings of IDS varied greatly with observation of linear, band-like, branch-like, plate-like and minute ring enhancements. These findings closely reflected the size, aggregation pattern, and distribution of intraductal lesions. In particular, minute ring enhancement was only observed in 4 comedo-type lesions. This pattern of enhancement is considered to reflect elevated intraductal cellular density with necrosis in the central region. (author)

  10. High-resolution, label-free imaging of living cells with direct electron-beam-excitation-assisted optical microscopy.

    Science.gov (United States)

    Nawa, Yasunori; Inami, Wataru; Lin, Sheng; Kawata, Yoshimasa; Terakawa, Susumu

    2015-06-01

    High spatial resolution microscope is desired for deep understanding of cellular functions, in order to develop medical technologies. We demonstrate high-resolution imaging of un-labelled organelles in living cells, in which live cells on a 50 nm thick silicon nitride membrane are imaged by autofluorescence excited with a focused electron beam through the membrane. Electron beam excitation enables ultrahigh spatial resolution imaging of organelles, such as mitochondria, nuclei, and various granules. Since the autofluorescence spectra represent molecular species, this microscopy allows fast and detailed investigations of cellular status in living cells.

  11. High-speed, high-resolution optical coherence tomography retinal imaging with a frequency-swept laser at 850 nm.

    Science.gov (United States)

    Srinivasan, V J; Huber, R; Gorczynska, I; Fujimoto, J G; Jiang, J Y; Reisen, P; Cable, A E

    2007-02-15

    High-speed, high-resolution optical coherence tomography (OCT) imaging of the human retina is demonstrated using a frequency-swept laser at 850 nm. A compact external cavity semiconductor laser design, optimized for swept-source ophthalmic OCT, is described. The laser enables an effective 16 kHz sweep rate with >10 mm coherence length and a tuning range of approximately 35 nm full width at half-maximum, yielding an axial resolution of <7 micro m in tissue.

  12. Photonics-based broadband radar for high-resolution and real-time inverse synthetic aperture imaging.

    Science.gov (United States)

    Zhang, Fangzheng; Guo, Qingshui; Wang, Ziqian; Zhou, Pei; Zhang, Guoqiang; Sun, Jun; Pan, Shilong

    2017-07-10

    A photonics-based radar with generation and de-chirp processing of broadband linear frequency modulated continuous-wave (LFMCW) signal in optical domain is proposed for high-resolution and real-time inverse synthetic aperture radar (ISAR) imaging. In the proposed system, a broadband LFMCW signal is generated by a photonic frequency quadrupler based on a single integrated electro-optical modulator, and the echoes reflected from the targets are de-chirped to a low frequency signal by a microwave photonic frequency mixer. The proposed radar can operate at a high frequency with a large bandwidth, and thus achieve an ultra-high range resolution for ISAR imaging. Thanks to the wideband photonic de-chirp technique, the radar receiver could apply low-speed analog-to-digital conversion and mature digital signal processing, which makes real-time ISAR imaging possible. A K-band photonics-based radar with an instantaneous bandwidth of 8 GHz (18-26 GHz) is established and its performance for ISAR imaging is experimentally investigated. Results show that a recorded two-dimensional imaging resolution of ~2 cm × ~2 cm is achieved with a sampling rate of 100 MSa/s in the receiver. Besides, fast ISAR imaging with 100 frames per second is verified. The proposed radar is an effective solution to overcome the limitations on operation bandwidth and processing speed of current radar imaging technologies, which may enable applications where high-resolution and real-time radar imaging is required.

  13. A Feasibility Study of Sea Ice Motion and Deformation Measurements Using Multi-Sensor High-Resolution Optical Satellite Images

    Directory of Open Access Journals (Sweden)

    Chang-Uk Hyun

    2017-09-01

    Full Text Available Sea ice motion and deformation have generally been measured using low-resolution passive microwave or mid-resolution radar remote sensing datasets of daily (or few days intervals to monitor long-term trends over a wide polar area. This feasibility study presents an application of high-resolution optical images from operational satellites, which have become more available in polar regions, for sea ice motion and deformation measurements. The sea ice motion, i.e., Lagrangian vector, is measured by using a maximum cross-correlation (MCC technique and multi-temporal high-resolution images acquired on 14–15 August 2014 from multiple spaceborne sensors on board Korea Multi-Purpose Satellites (KOMPSATs with short acquisition time intervals. The sea ice motion extracted from the six image pairs of the spatial resolutions were resampled to 4 m and 15 m yields with vector length measurements of 57.7 m root mean square error (RMSE and −11.4 m bias and 60.7 m RMSE and −13.5 m bias, respectively, compared with buoy location records. The errors from both resolutions indicate more accurate measurements than from conventional sea ice motion datasets from passive microwave and radar data in ice and water mixed surface conditions. In the results of sea ice deformation caused by interaction of individual ice floes, while free drift patterns of ice floes were delineated from the 4 m spatial resolution images, the deformation was less revealing in the 15 m spatial resolution image pairs due to emphasized discretization uncertainty from coarser pixel sizes. The results demonstrate that using multi-temporal high-resolution optical satellite images enabled precise image block matching in the melting season, thus this approach could be used for expanding sea ice motion and deformation dataset, with an advantage of frequent image acquisition capability in multiple areas by means of many operational satellites.

  14. MACSAT - A Mini-Satellite Approach to High Resolution Space Imaging

    OpenAIRE

    Kim, Byung-Jin; Park, Sungdong; Kim, Ee-Eul; Chang, Hyon-Sock; Park, Wonkyu; Seon, Jongho; Ismail, Maszlan; Ad-Rasheed, Ad-Aziz; Sabirin-Arshad, Ahmad

    2003-01-01

    To be launched in 2004, MACSAT is a 200kg satellite, designed to provide 2.5m ground sampling distance (GSD) resolution imagery on a near equatorial orbit (NEqO). The mission objective is to demonstrate the capability of a high-resolution remote sensing satellite system on a NEqO. Initi-ated by ATSB, the proprietary NEqO mission has advantages for monitoring the environment of equatorial regions of Malaysia with unique revisit characteristics from the baseline circular orbit of 7 degrees of i...

  15. Task-Based Modeling of a 5k Ultra-High-Resolution Medical Imaging System for Digital Breast Tomosynthesis.

    Science.gov (United States)

    Zhao, Chumin; Kanicki, Jerzy

    2017-09-01

    High-resolution, low-noise X-ray detectors based on CMOS active pixel sensor (APS) technology have demonstrated superior imaging performance for digital breast tomosynthesis (DBT). This paper presents a task-based model for a high-resolution medical imaging system to evaluate its ability to detect simulated microcalcifications and masses as lesions for breast cancer. A 3-D cascaded system analysis for a 50- [Formula: see text] pixel pitch CMOS APS X-ray detector was integrated with an object task function, a medical imaging display model, and the human eye contrast sensitivity function to calculate the detectability index and area under the ROC curve (AUC). It was demonstrated that the display pixel pitch and zoom factor should be optimized to improve the AUC for detecting small microcalcifications. In addition, detector electronic noise of smaller than 300 e - and a high display maximum luminance (>1000 cd/cm 2 ) are desirable to distinguish microcalcifications of [Formula: see text] in size. For low contrast mass detection, a medical imaging display with a minimum of 12-bit gray levels is recommended to realize accurate luminance levels. A wide projection angle range of greater than ±30° in combination with the image gray level magnification could improve the mass detectability especially when the anatomical background noise is high. On the other hand, a narrower projection angle range below ±20° can improve the small, high contrast object detection. Due to the low mass contrast and luminance, the ambient luminance should be controlled below 5 cd/ [Formula: see text]. Task-based modeling provides important firsthand imaging performance of the high-resolution CMOS-based medical imaging system that is still at early stage development for DBT. The modeling results could guide the prototype design and clinical studies in the future.

  16. Damage Mapping of Powdery Mildew in Winter Wheat with High-Resolution Satellite Image

    Directory of Open Access Journals (Sweden)

    Lin Yuan

    2014-04-01

    Full Text Available Powdery mildew, caused by the fungus Blumeria graminis, is a major winter wheat disease in China. Accurate delineation of powdery mildew infestations is necessary for site-specific disease management. In this study, high-resolution multispectral imagery of a 25 km2 typical outbreak site in Shaanxi, China, taken by a newly-launched satellite, SPOT-6, was analyzed for mapping powdery mildew disease. Two regions with high representation were selected for conducting a field survey of powdery mildew. Three supervised classification methods—artificial neural network, mahalanobis distance, and maximum likelihood classifier—were implemented and compared for their performance on disease detection. The accuracy assessment showed that the ANN has the highest overall accuracy of 89%, following by MD and MLC with overall accuracies of 84% and 79%, respectively. These results indicated that the high-resolution multispectral imagery with proper classification techniques incorporated with the field investigation can be a useful tool for mapping powdery mildew in winter wheat.

  17. A post-stroke rehabilitation system integrating robotics, VR and high-resolution EEG imaging.

    Science.gov (United States)

    Steinisch, Martin; Tana, Maria Gabriella; Comani, Silvia

    2013-09-01

    We propose a system for the neuro-motor rehabilitation of upper limbs in stroke survivors. The system is composed of a passive robotic device (Trackhold) for kinematic tracking and gravity compensation, five dedicated virtual reality (VR) applications for training of distinct movement patterns, and high-resolution EEG for synchronous monitoring of cortical activity. In contrast to active devices, the Trackhold omits actuators for increased patient safety and acceptance levels, and for reduced complexity and costs. VR applications present all relevant information for task execution as easy-to-understand graphics that do not need any written or verbal instructions. High-resolution electroencephalography (HR-EEG) is synchronized with kinematic data acquisition, allowing for the epoching of EEG signals on the basis of movement-related temporal events. Two healthy volunteers participated in a feasibility study and performed a protocol suggested for the rehabilitation of post-stroke patients. Kinematic data were analyzed by means of in-house code. Open source packages (EEGLAB, SPM, and GMAC) and in-house code were used to process the neurological data. Results from kinematic and EEG data analysis are in line with knowledge from currently available literature and theoretical predictions, and demonstrate the feasibility and potential usefulness of the proposed rehabilitation system to monitor neuro-motor recovery.

  18. A New Method Based on Two-Stage Detection Mechanism for Detecting Ships in High-Resolution SAR Images

    Directory of Open Access Journals (Sweden)

    Xu Yongli

    2017-01-01

    Full Text Available Ship detection in synthetic aperture radar (SAR remote sensing images, being a fundamental but challenging problem in the field of satellite image analysis, plays an important role for a wide range of applications and is receiving significant attention in recent years. Aiming at the requirements of ship detection in high-resolution SAR images, the accuracy, the intelligent level, a better real-time operation and processing efficiency, The characteristics of ocean background and ship target in high-resolution SAR images were analyzed, we put forward a ship detection algorithm in high-resolution SAR images. The algorithm consists of two detection stages: The first step designs a pre-training classifier based on improved spectral residual visual model to obtain the visual salient regions containing ship targets quickly, then achieve the purpose of probably detection of ships. In the second stage, considering the Bayesian theory of binary hypothesis detection, a local maximum posterior probability (MAP classifier is designed for the classification of pixels. After the parameter estimation and judgment criterion, the classification of pixels are carried out in the target areas to achieve the classification of two types of pixels in the salient regions. In the paper, several types of satellite image data, such as TerraSAR-X (TS-X, Radarsat-2, are used to evaluate the performance of detection methods. Comparing with classical CFAR detection algorithms, experimental results show that the algorithm can achieve a better effect of suppressing false alarms, which caused by the speckle noise and ocean clutter background inhomogeneity. At the same time, the detection speed is increased by 25% to 45%.

  19. Imaging of posterior tibial tendon dysfunction—Comparison of high-resolution ultrasound and 3 T MRI

    Energy Technology Data Exchange (ETDEWEB)

    Arnoldner, Michael A., E-mail: michael.arnoldner@meduniwien.ac.at [Medical University of Vienna, Vienna General Hospital, Department of Biomedical Imaging and Image-guided Therapy, Währinger Gürtel 18-20, 1090 Vienna (Austria); Gruber, Michael [Medical University of Vienna, Vienna General Hospital, Department of Biomedical Imaging and Image-guided Therapy, Währinger Gürtel 18-20, 1090 Vienna (Austria); Syré, Stefanie [Medical University of Vienna, Vienna General Hospital, Department of Trauma-Surgery, Währinger Gürtel 18-20, 1090 Vienna (Austria); Kristen, Karl-Heinz [Foot & Ankle Centre Vienna, Alser Straße 43/8, 1080 Vienna (Austria); Trnka, Hans-Jörg [Foot & Ankle Centre Vienna, Alser Straße 43/8, 1080 Vienna (Austria); Orthopaedic Hospital Vienna, Speisinger Straße 109, 1130 Vienna (Austria); Kainberger, Franz; Bodner, Gerd [Medical University of Vienna, Vienna General Hospital, Department of Biomedical Imaging and Image-guided Therapy, Währinger Gürtel 18-20, 1090 Vienna (Austria)

    2015-09-15

    Highlights: • 18 MHz high-resolution ultrasound appears to be slightly more accurate than 3 T MRI in the diagnosis of PTTD. • High-resolution ultrasound is recommended as an initial diagnostic tool. • Long-lasting PTT discomfort may require MRI. • Other pathologies can mimic PTTD. - Abstract: Purpose: Posterior tibial tendon dysfunction is the most common cause of acquired asymmetric flatfoot deformity. The purpose of this study was to determine and compare the diagnostic value of MRI and high-resolution ultrasound (HR-US) in posterior tibial tendon dysfunction (PTTD), and assess their correlation with intraoperative findings. Materials and methods: We reviewed 23 posterior tibial tendons in 23 patients with clinical findings of PTTD (13 females, 10 males; mean age, 50 years) with 18 MHz HR-US and 3 T MRI. Surgical intervention was performed in nine patients. Results: HR-US findings included 2 complete tears, 6 partial tears, 10 tendons with tendinosis, and 5 unremarkable tendons. MRI demonstrated 2 complete tears, 7 partial tears, 10 tendons with tendinosis, and 4 unremarkable tendons. HR-US and MRI were concordant in 20/23 cases (87%). Image findings for HR-US were confirmed in six of nine patients (66.7%) by intraoperative inspection, whereas imaging findings for MRI were concordant with five of nine cases (55.6%). Conclusion: Our results indicate that HR-US can be considered slightly more accurate than MRI in the detection of PTTD.

  20. A high-resolution imaging technique using a whole-body, research photon counting detector CT system

    Science.gov (United States)

    Leng, S.; Yu, Z.; Halaweish, A.; Kappler, S.; Hahn, K.; Henning, A.; Li, Z.; Lane, J.; Levin, D. L.; Jorgensen, S.; Ritman, E.; McCollough, C.

    2016-03-01

    A high-resolution (HR) data collection mode has been introduced to a whole-body, research photon-counting-detector CT system installed in our laboratory. In this mode, 64 rows of 0.45 mm x 0.45 mm detector pixels were used, which corresponded to a pixel size of 0.25 mm x 0.25 mm at the iso-center. Spatial resolution of this HR mode was quantified by measuring the MTF from a scan of a 50 micron wire phantom. An anthropomorphic lung phantom, cadaveric swine lung, temporal bone and heart specimens were scanned using the HR mode, and image quality was subjectively assessed by two experienced radiologists. High spatial resolution of the HR mode was evidenced by the MTF measurement, with 15 lp/cm and 20 lp/cm at 10% and 2% modulation. Images from anthropomorphic phantom and cadaveric specimens showed clear delineation of small structures, such as lung vessels, lung nodules, temporal bone structures, and coronary arteries. Temporal bone images showed critical anatomy (i.e. stapes superstructure) that was clearly visible in the PCD system. These results demonstrated the potential application of this imaging mode in lung, temporal bone, and vascular imaging. Other clinical applications that require high spatial resolution, such as musculoskeletal imaging, may also benefit from this high resolution mode.

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

    Science.gov (United States)

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

    2008-12-01

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

  2. High resolution imaging of vadose zone transport using crosswell radar and seismic methods; TOPICAL

    International Nuclear Information System (INIS)

    Majer, Ernest L.; Williams, Kenneth H.; Peterson, John E.; Daley, Thomas E.

    2001-01-01

    The summary and conclusions are that overall the radar and seismic results were excellent. At the time of design of the experiments we did not know how well these two methods could penetrate or resolve the moisture content and structure. It appears that the radar could easily go up to 5, even 10 meters between boreholes at 200 Mhz and even father (up to 20 to 40 m) at 50 Mhz. The seismic results indicate that at several hundred hertz propagation of 20 to 30 meters giving high resolution is possible. One of the most important results, however is that together the seismic and radar are complementary in their properties estimation. The radar being primarily sensitive to changes in moisture content, and the seismic being primarily sensitive to porosity. Taken in a time lapse sense the radar can show the moisture content changes to a high resolution, with the seismic showing high resolution lithology. The significant results for each method are: Radar: (1) Delineated geological layers 0.25 to 3.5 meters thick with 0.25 m resolution; (2) Delineated moisture movement and content with 0.25 m resolution; (3) Compared favorably with neutron probe measurements; and (4) Penetration up to 30 m. Radar results indicate that the transport of the riverwater is different from that of the heavier and more viscous sodium thiosulfate. It appears that the heavier fluids are not mixing readily with the in-situ fluids and the transport may be influenced by them. Seismic: (1) Delineated lithology at .25 m resolution; (2) Penetration over 20 meters, with a possibility of up to 30 or more meters; and (3) Maps porosity and density differences of the sediments. Overall the seismic is mapping the porosity and density distribution. The results are consistent with the flow field mapped by the radar, there is a change in flow properties at the 10 to 11 meter depth in the flow cell. There also appears to be break through by looking at the radar data with the denser sodium thiosulfate finally

  3. Comparison of quantitative myocardial perfusion imaging CT to fluorescent microsphere-based flow from high-resolution cryo-images

    Science.gov (United States)

    Eck, Brendan L.; Fahmi, Rachid; Levi, Jacob; Fares, Anas; Wu, Hao; Li, Yuemeng; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

    2016-03-01

    Myocardial perfusion imaging using CT (MPI-CT) has the potential to provide quantitative measures of myocardial blood flow (MBF) which can aid the diagnosis of coronary artery disease. We evaluated the quantitative accuracy of MPI-CT in a porcine model of balloon-induced LAD coronary artery ischemia guided by fractional flow reserve (FFR). We quantified MBF at baseline (FFR=1.0) and under moderate ischemia (FFR=0.7) using MPI-CT and compared to fluorescent microsphere-based MBF from high-resolution cryo-images. Dynamic, contrast-enhanced CT images were obtained using a spectral detector CT (Philips Healthcare). Projection-based mono-energetic images were reconstructed and processed to obtain MBF. Three MBF quantification approaches were evaluated: singular value decomposition (SVD) with fixed Tikhonov regularization (ThSVD), SVD with regularization determined by the L-Curve criterion (LSVD), and Johnson-Wilson parameter estimation (JW). The three approaches over-estimated MBF compared to cryo-images. JW produced the most accurate MBF, with average error 33.3+/-19.2mL/min/100g, whereas LSVD and ThSVD had greater over-estimation, 59.5+/-28.3mL/min/100g and 78.3+/-25.6 mL/min/100g, respectively. Relative blood flow as assessed by a flow ratio of LAD-to-remote myocardium was strongly correlated between JW and cryo-imaging, with R2=0.97, compared to R2=0.88 and 0.78 for LSVD and ThSVD, respectively. We assessed tissue impulse response functions (IRFs) from each approach for sources of error. While JW was constrained to physiologic solutions, both LSVD and ThSVD produced IRFs with non-physiologic properties due to noise. The L-curve provided noise-adaptive regularization but did not eliminate non-physiologic IRF properties or optimize for MBF accuracy. These findings suggest that model-based MPI-CT approaches may be more appropriate for quantitative MBF estimation and that cryo-imaging can support the development of MPI-CT by providing spatial distributions of MBF.

  4. The use of high-resolution digital imaging technology for small diameter K-file length determination in endodontics.

    Science.gov (United States)

    Vandenberghe, Bart; Bud, Marius; Sutanto, Asti; Jacobs, Reinhilde

    2010-04-01

    To assess the reliability of high resolution intra-oral photostimulable storage phosphor (PSP) and complementary metal-oxide semiconductor (CMOS) imaging systems for working length (WL) assessment of small K-files in narrow and curved root canals. Eleven narrow and curved canals from extracted molars were used as pre-test for sample-size calculation. Nineteen canals from four cadavers were used for endodontic length assessment in the final study. Small K-files (ISO size 6, 8, and 10) were introduced into the canals at prepared length. Digital intra-oral radiographs were obtained using high-resolution Vistascan PSP plates and Sigma M CMOS active pixel sensor with a DC X-ray tube at 70 kV, 7 mA, and 0.16 s. Both image series were assessed with and without use of a dedicated endodontic filter. Three observers measured WLs for comparison to the gold standards of a digital millimeter ruler. Multiple regression analysis of the dependent measurements revealed no significant influence of imaging sensor (PSP or CMOS, p = 0.34) and image processing (p = 0.97). For ISO file size, however, there was a significant difference (p = 0.08) at a level of 10%. Observers mostly underestimated lengths using PSP but overestimated them on CMOS. Almost all radiographic measurements (96-98%) were within 2-mm deviation, while 71% to 82% deviated within 1 mm. Dedicated filtering and sensor type did not influence the outcome of WL determination of small file sizes when using high-resolution imaging sensors. WL determination with ISO file 6 did show a significant difference compared to ISO 8 and 10 but mostly for deviations <1.5 mm.

  5. A novel approach to contrast-enhanced breast magnetic resonance imaging for screening: high-resolution ultrafast dynamic imaging.

    Science.gov (United States)

    Mann, Ritse M; Mus, Roel D; van Zelst, Jan; Geppert, Christian; Karssemeijer, Nico; Platel, Bram

    2014-09-01

    The use of breast magnetic resonance imaging (MRI) as screening tool has been stalled by high examination costs. Scan protocols have lengthened to optimize specificity. Modern view-sharing sequences now enable ultrafast dynamic whole-breast MRI, allowing much shorter and more cost-effective procedures. This study evaluates whether dynamic information from ultrafast breast MRI can be used to replace standard dynamic information to preserve accuracy. We interleaved 20 ultrafast time-resolved angiography with stochastic trajectory (TWIST) acquisitions (0.9 × 1 × 2.5 mm, temporal resolution, 4.3 seconds) during contrast inflow in a regular high-resolution dynamic MRI protocol. A total of 160 consecutive patients with 199 enhancing abnormalities (95 benign and 104 malignant) were included. The maximum slope of the relative enhancement versus time curve (MS) obtained from the TWIST and curve type obtained from the regular dynamic sequence as defined in the breast imaging reporting and data system (BIRADS) lexicon were recorded. Diagnostic performance was compared using receiver operating characteristic analysis. All lesions were visible on both the TWIST and standard series. Maximum slope allows discrimination between benign and malignant disease with high accuracy (area under the curve, 0.829). Types of MS were defined in analogy to BIRADS curve types: MS type 3 implies a high risk of malignancy (MS >13.3%/s; specificity, 85%), MS type 2 yields intermediate risk (MS 6.4%/s), and MS type 1 implies a low risk (MS BIRADS curve type analysis does (area under the curve, 0.812 vs 0.692; P = 0.0061). Ultrafast dynamic breast MRI allows detection of breast lesions and classification with high accuracy using MS. This allows substantial shortening of scan protocols and hence reduces imaging costs, which is beneficial especially for screening.

  6. Application of Radar and Optical Images to Create Copernicus High Resolution Layers: Case Studies in Hungary

    Science.gov (United States)

    Surek, Gyorgy; Nador, Gizella; Friedl, Zoltan; Gyimesi, Balint; Rada, Matyas; Akos Gera, David; Hubik, Iren; Rotterne Kulesar, Aniko; Totok, Cecilia

    2016-08-01

    Injection of SAR imagery based information in the production of Copernicus High Resolution Layers can help to refine information served by optical satellite imagery, together with a-priori knowledge it may overcome the gaps caused by the cloud cover issue. However, this requires a methodological adaptation, given the different nature of SAR as compared to optical data. The methodological adaptation shall allow for an operational implementation, and shall help reducing the elapsed time between available satellite imagery. This requires the analysis of the potential use of SAR based imagery in the COPERNICUS land context, supported with case studies. In this paper the contribution of radar polarimetry for distinguishing land cover categories is evaluated.

  7. New tools and techniques for high-resolution seafloor imaging developed at the University of Hawaii

    Science.gov (United States)

    Edwards, M.; Appelgate, B.; Rognstad, M.; Davis, R.; Johnson, P.

    2003-04-01

    Since the mid-1980's, the University of Hawaii has established a strong reputation for creating regional maps of seafloor terrain using shallow-towed systems that simultaneously collect bathymetry and backscatter data. Over the past several years we have begun developing analogous approaches for near-bottom systems including the DSL-120A and the IMI-30. The former system is a 120 kHz sonar developed in collaboration with colleagues at the Woods Hole Oceanographic Institution; the latter is a 30 kHz sonar presently under development at the University of Hawaii. IMI-30 is scheduled to complete its first field trials in March 2003, just prior to the EGS/AGU meeting. In designing these systems we have continued to evolve the digital hardware electronics that were first developed for the HAWAII MR1 12 kHz sonar. This nearly all-digital approach has proven both flexible and robust, and promotes easier debugging and repair of hardware components. Software efforts for the new systems have focused on scalable visual displays of both non-navigated and navigated versions of different data fields to promote real-time quality assurance and facilitate post-acquisition data processing. Significant effort has been expended to improve the quality of our data products, both to bring charts and data quality estimates up to standards analogous to those set by the private sector and to exploit the continually improving capabilities of three-dimensional visualization tools such as ArcView and ERMapper. Of particular interest to the high-resolution mapping community are our efforts to develop web-based data archives that provide quick access to various types of high-resolution maps and tens of thousands of digial photographs, all of which have been geographically linked.

  8. ASTC-MIMO-TOPS Mode with Digital Beam-Forming in Elevation for High-Resolution Wide-Swath Imaging

    Directory of Open Access Journals (Sweden)

    Pingping Huang

    2015-03-01

    Full Text Available Future spaceborne synthetic aperture radar (SAR missions require complete and frequent coverage of the earth with a high resolution. Terrain Observation by Progressive Scans (TOPS is a novel wide swath mode but has impaired azimuth resolution. In this paper, an innovative extended TOPS mode named Alamouti Space-time Coding multiple-input multiple-output TOPS (ASTC-MIMO-TOPS mode combined with digital beam-forming (DBF in elevation and multi-aperture SAR signal reconstruction in azimuth is proposed. This innovative mode achieves wide-swath coverage with a high geometric resolution and also overcomes major drawbacks in conventional MIMO SAR systems. The data processing scheme of this imaging scheme is presented in detail. The designed system example of the proposed ASTC-MIMO-TOPS mode, which has the imaging capacity of a 400 km wide swath with an azimuth resolution of 3 m, is given. Its system performance analysis results and simulated imaging results on point targets demonstrate the potential of the proposed novel spaceborne SAR mode for high-resolution wide-swath (HRWS imaging.

  9. Development of a 55 μm pitch 8 inch CMOS image sensor for the high resolution NDT application

    Science.gov (United States)

    Kim, M. S.; Kim, G.; Cho, G.; Kim, D.

    2016-11-01

    A CMOS image sensor (CIS) with a large area for the high resolution X-ray imaging was designed. The sensor has an active area of 125 × 125 mm2 comprised with 2304 × 2304 pixels and a pixel size of 55 × 55 μm2. First batch samples were fabricated by using an 8 inch silicon CMOS image sensor process with a stitching method. In order to evaluate the performance of the first batch samples, the electro-optical test and the X-ray test after coupling with an image intensifier screen were performed. The primary results showed that the performance of the manufactured sensors was limited by a large stray capacitance from the long path length between the analog multiplexer on the chip and the bank ADC on the data acquisition board. The measured speed and dynamic range were limited up to 12 frame per sec and 55 dB respectively, but other parameters such as the MTF, NNPS and DQE showed a good result as designed. Based on this study, the new X-ray CIS with ~ 50 μm pitch and ~ 150 cm2 active area are going to be designed for the high resolution X-ray NDT equipment for semiconductor and PCB inspections etc.

  10. An optical imaging chamber for viewing living plant cells and tissues at high resolution for extended periods.

    Science.gov (United States)

    Calder, Grant; Hindle, Chris; Chan, Jordi; Shaw, Peter

    2015-01-01

    Recent developments in both microscopy and fluorescent protein technologies have made live imaging a powerful tool for the study of plant cells. However, the complications of keeping plant material alive during a long duration experiment while maintaining maximum resolution has limited the use of these methods. Here, we describe an imaging chamber designed to overcome these limitations, which is flexible enough to support a range of sizes of plant materials. We were able use confocal microscopy to follow growth and development of plant cells and tissues over several days. The chamber design is based on a perfusion system, so that the addition of drugs and other experimental treatments are also possible. In this article we present a design of imaging chamber that makes it possible to image plant material with high resolution for extended periods of time.

  11. High-resolution echocardiography

    Science.gov (United States)

    Nathan, R.

    1979-01-01

    High resolution computer aided ultrasound system provides two-and three-dimensional images of beating heart from many angles. System provides means for determining whether small blood vessels around the heart are blocked or if heart wall is moving normally without interference of dead and noncontracting muscle tissue.

  12. Diagnostic imaging of gout: comparison of high-resolution US versus conventional X-ray

    International Nuclear Information System (INIS)

    Rettenbacher, Thomas; Ennemoser, Sybille; Weirich, Harald; Ulmer, Hanno; Hartig, Frank; Klotz, Werner; Herold, Manfred

    2008-01-01

    The aim was to compare X-ray and ultrasound (US) in diagnosing gout. In a prospective study, 105 consecutive patients with clinical suspicion of gout underwent conventional X-ray und high-resolution US in order to help in arriving at a definite diagnosis. X-ray findings suggestive of gout included soft-tissue opacifications with densities between soft tissue and bone, articular and periarticular bone erosions, and osteophytes at the margins of opacifications or erosions. US findings suggestive of gout included bright stippled foci and hyperechoic soft-tissue areas. Fifty-five patients had a definite diagnosis of gout (102 involved sites), 31 patients were diagnosed as having another disease (59 involved sites), and 19 patients were excluded from the study because a definite diagnosis could not be established. X-ray suggested gout with a sensitivity of 31% (32/102) and a specificity of 93% (55/59), whereas US suggested gout with a sensitivity of 96% (98/102) and a specificity of 73% (43/59). US was much more sensitive than conventional X-ray but less specific. Our data show that US often provided additional diagnostic information in patients with clinical suspicion of gout when laboratory findings and X-ray results were negative or inconclusive and should therefore be used in these cases. (orig.)

  13. High resolution imaging of particle interactions in a large bubble chamber using holographic techniques

    International Nuclear Information System (INIS)

    Akbari, Homaira.

    1988-01-01

    Particle interactions were recorded holographically in a large volume of the 15-foot Bubble Chamber at Fermilab. This cryogenic bubble chamber was filled with a heavy Neon-Hydrogen mixture and was exposed to a wideband neutrino beam with mean energy of 150 GeV. The use of holography in combination with conventional photography provides a powerful tool for direct detection of short-lived particles. Holography gives a high resolution over a large depth of field which can not be achieved with conventional photography. A high-power pulsed ruby laser was used as the holographic light source. Since short pulses of some 50 ns duration at the required energy were found to give rise to boiling during the chamber's expansion, a reduction of the instantaneous power at a given energy was required to suppress this unwanted after-effect. This was achieved by developing a unique technique for stretching the pulses using an electro-optic feedback loop. One hundred thousand holograms were produced during a wide-band neutrino experiment (E-632, 1985) using a dark-field holographic system. Analysis of a sample of holograms shows a resolution of 150 μm was achieved in an ovoidal shape fiducial volume of 0.48 m 3 % of the 14 m 3 total fiducial volume of the chamber

  14. Spectrum of high-resolution computed tomography imaging in occupational lung disease

    Directory of Open Access Journals (Sweden)

    Bhawna Satija

    2013-01-01

    Full Text Available Damage to the lungs caused by dusts or fumes or noxious substances inhaled by workers in certain specific occupation is known as occupational lung disease. Recognition of occupational lung disease is especially important not only for the primary worker, but also because of the implications with regard to primary and secondary disease prevention in the exposed co-workers. Although many of the disorders can be detected on chest radiography, high-resolution computed tomography (HRCT is superior in delineating the lung architecture and depicting pathology. The characteristic radiological features suggest the correct diagnosis in some, whereas a combination of clinical features, occupational history, and radiological findings is essential in establishing the diagnosis in others. In the presence of a history of exposure and consistent clinical features, the diagnosis of even an uncommon occupational lung disease can be suggested by the characteristic described HRCT findings. In this article, we briefly review the HRCT appearance of a wide spectrum of occupational lung diseases.

  15. Preparation of developing Xenopus muscle for sarcomeric protein localization by high-resolution imaging.

    Science.gov (United States)

    Nworu, Chinedu U; Krieg, Paul A; Gregorio, Carol C

    2014-04-01

    Mutations in several sarcomeric proteins have been linked to various human myopathies. Therefore, having an in vivo developmental model available that develops quickly and efficiently is key for investigators to elucidate the critical steps, components and signaling pathways involved in building a myofibril; this is the pivotal foundation for deciphering disease mechanisms as well as the development of myopathy-related therapeutics. Although striated muscle cell culture studies have been extremely informative in providing clues to both the distribution and functions of sarcomeric proteins, myocytes in vivo develop in an irreproducible 3D environment. Xenopus laevis (frog) embryos are cost effective, compliant to protein level manipulations and develop relatively quickly (⩽ a week) in a petri dish, thus providing a powerful system for de novo myofibrillogenesis studies. Although fluorophore-conjugated phalloidin labeling is the gold standard approach for investigating actin-thin filament architecture, it is well documented that phalloidin-labeling can be challenging and inconsistent within Xenopus embryos. Therefore we highlight several techniques that can be utilized to preserve both antibody and fluorophore-conjugated phalloidin labeling within Xenopus embryos for high-resolution fluorescence microscopy. Copyright © 2013. Published by Elsevier Inc.

  16. PulseCam: high-resolution blood perfusion imaging using a camera and a pulse oximeter.

    Science.gov (United States)

    Kumar, Mayank; Suliburk, James; Veeraraghavan, Ashok; Sabharwal, Ashutosh

    2016-08-01

    Measuring blood perfusion is important in medical care as an indicator of injury and disease. However, currently available devices to measure blood perfusion like laser Doppler flowmetry are bulky, expensive, and cumbersome to use. An alternative low-cost and portable camera-based blood perfusion measurement system has recently been proposed, but such camera-only system produces noisy low-resolution blood perfusion maps. In this paper, we propose a new multi-sensor modality, named PulseCam, for measuring blood perfusion by combining a traditional pulse oximeter with a video camera in a unique way to provide low noise and high-resolution blood perfusion maps. Our proposed multi-sensor modality improves per pixel signal to noise ratio of measured perfusion map by up to 3 dB and improves the spatial resolution by 2 - 3 times compared to best known camera-only methods. Blood perfusion measured in the palm using our PulseCam setup during a post-occlusive reactive hyperemia (PORH) test replicates standard PORH response curve measured using laser Doppler flowmetry device but with much lower cost and a portable setup making it suitable for further development as a clinical device.

  17. Automated analysis of heterogeneous carbon nanostructures by high-resolution electron microscopy and on-line image processing

    Energy Technology Data Exchange (ETDEWEB)

    Toth, P., E-mail: toth.pal@uni-miskolc.hu [Department of Chemical Engineering, University of Utah, 50 S. Central Campus Drive, Salt Lake City, UT 84112-9203 (United States); Farrer, J.K. [Department of Physics and Astronomy, Brigham Young University, N283 ESC, Provo, UT 84602 (United States); Palotas, A.B. [Department of Combustion Technology and Thermal Energy, University of Miskolc, H3515, Miskolc-Egyetemvaros (Hungary); Lighty, J.S.; Eddings, E.G. [Department of Chemical Engineering, University of Utah, 50 S. Central Campus Drive, Salt Lake City, UT 84112-9203 (United States)

    2013-06-15

    High-resolution electron microscopy is an efficient tool for characterizing heterogeneous nanostructures; however, currently the analysis is a laborious and time-consuming manual process. In order to be able to accurately and robustly quantify heterostructures, one must obtain a statistically high number of micrographs showing images of the appropriate sub-structures. The second step of analysis is usually the application of digital image processing techniques in order to extract meaningful structural descriptors from the acquired images. In this paper it will be shown that by applying on-line image processing and basic machine vision algorithms, it is possible to fully automate the image acquisition step; therefore, the number of acquired images in a given time can be increased drastically without the need for additional human labor. The proposed automation technique works by computing fields of structural descriptors in situ and thus outputs sets of the desired structural descriptors in real-time. The merits of the method are demonstrated by using combustion-generated black carbon samples. - Highlights: ► The HRTEM analysis of heterogeneous nanostructures is a tedious manual process. ► Automatic HRTEM image acquisition and analysis can improve data quantity and quality. ► We propose a method based on on-line image analysis for the automation of HRTEM image acquisition. ► The proposed method is demonstrated using HRTEM images of soot particles.

  18. HIGH-RESOLUTION LINEAR POLARIMETRIC IMAGING FOR THE EVENT HORIZON TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Chael, Andrew A.; Johnson, Michael D.; Narayan, Ramesh; Doeleman, Sheperd S. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Wardle, John F. C. [Brandeis University, Physics Department, Waltham, MA 02454 (United States); Bouman, Katherine L., E-mail: achael@cfa.harvard.edu [Massachusetts Institute of Technology, Computer Science and Artificial Intelligence Laboratory, 32 Vassar Street, Cambridge, MA 02139 (United States)

    2016-09-20

    Images of the linear polarizations of synchrotron radiation around active galactic nuclei (AGNs) highlight their projected magnetic field lines and provide key data for understanding the physics of accretion and outflow from supermassive black holes. The highest-resolution polarimetric images of AGNs are produced with Very Long Baseline Interferometry (VLBI). Because VLBI incompletely samples the Fourier transform of the source image, any image reconstruction that fills in unmeasured spatial frequencies will not be unique and reconstruction algorithms are required. In this paper, we explore some extensions of the Maximum Entropy Method (MEM) to linear polarimetric VLBI imaging. In contrast to previous work, our polarimetric MEM algorithm combines a Stokes I imager that only uses bispectrum measurements that are immune to atmospheric phase corruption, with a joint Stokes Q and U imager that operates on robust polarimetric ratios. We demonstrate the effectiveness of our technique on 7 and 3 mm wavelength quasar observations from the VLBA and simulated 1.3 mm Event Horizon Telescope observations of Sgr A* and M87. Consistent with past studies, we find that polarimetric MEM can produce superior resolution compared to the standard CLEAN algorithm, when imaging smooth and compact source distributions. As an imaging framework, MEM is highly adaptable, allowing a range of constraints on polarization structure. Polarimetric MEM is thus an attractive choice for image reconstruction with the EHT.

  19. Observing the Sun with the Atacama Large Millimeter/submillimeter Array (ALMA): High-Resolution Interferometric Imaging

    Science.gov (United States)

    Shimojo, M.; Bastian, T. S.; Hales, A. S.; White, S. M.; Iwai, K.; Hills, R. E.; Hirota, A.; Phillips, N. M.; Sawada, T.; Yagoubov, P.; Siringo, G.; Asayama, S.; Sugimoto, M.; Brajša, R.; Skokić, I.; Bárta, M.; Kim, S.; de Gregorio-Monsalvo, I.; Corder, S. A.; Hudson, H. S.; Wedemeyer, S.; Gary, D. E.; De Pontieu, B.; Loukitcheva, M.; Fleishman, G. D.; Chen, B.; Kobelski, A.; Yan, Y.

    2017-07-01

    Observations of the Sun at millimeter and submillimeter wavelengths offer a unique probe into the structure, dynamics, and heating of the chromosphere; the structure of sunspots; the formation and eruption of prominences and filaments; and energetic phenomena such as jets and flares. High-resolution observations of the Sun at millimeter and submillimeter wavelengths are challenging due to the intense, extended, low-contrast, and dynamic nature of emission from the quiet Sun, and the extremely intense and variable nature of emissions associated with energetic phenomena. The Atacama Large Millimeter/submillimeter Array (ALMA) was designed with solar observations in mind. The requirements for solar observations are significantly different from observations of sidereal sources and special measures are necessary to successfully carry out this type of observations. We describe the commissioning efforts that enable the use of two frequency bands, the 3-mm band (Band 3) and the 1.25-mm band (Band 6), for continuum interferometric-imaging observations of the Sun with ALMA. Examples of high-resolution synthesized images obtained using the newly commissioned modes during the solar-commissioning campaign held in December 2015 are presented. Although only 30 of the eventual 66 ALMA antennas were used for the campaign, the solar images synthesized from the ALMA commissioning data reveal new features of the solar atmosphere that demonstrate the potential power of ALMA solar observations. The ongoing expansion of ALMA and solar-commissioning efforts will continue to enable new and unique solar observing capabilities.

  20. Automatic Labelling and Selection of Training Samples for High-Resolution Remote Sensing Image Classification over Urban Areas

    Directory of Open Access Journals (Sweden)

    Xin Huang

    2015-12-01

    Full Text Available Supervised classification is the commonly used method for extracting ground information from images. However, for supervised classification, the selection and labelling of training samples is an expensive and time-consuming task. Recently, automatic information indexes have achieved satisfactory results for indicating different land-cover classes, which makes it possible to develop an automatic method for labelling the training samples instead of manual interpretation. In this paper, we propose a method for the automatic selection and labelling of training samples for high-resolution image classification. In this way, the initial candidate training samples can be provided by the information indexes and open-source geographical information system (GIS data, referring to the representative land-cover classes: buildings, roads, soil, water, shadow, and vegetation. Several operations are then applied to refine the initial samples, including removing overlaps, removing borders, and semantic constraints. The proposed sampling method is evaluated on a series of high-resolution remote sensing images over urban areas, and is compared to classification with manually labeled training samples. It is found that the proposed method is able to provide and label a large number of reliable samples, and can achieve satisfactory results for different classifiers. In addition, our experiments show that active learning can further enhance the classification performance, as active learning is used to choose the most informative samples from the automatically labeled samples.

  1. Polarized light imaging of birefringence and diattenuation at high resolution and high sensitivity

    International Nuclear Information System (INIS)

    Mehta, Shalin B; Shribak, Michael; Oldenbourg, Rudolf

    2013-01-01

    Polarized light microscopy provides unique opportunities for analyzing the molecular order in man-made and natural materials, including biological structures inside living cells, tissues, and whole organisms. 20 years ago, the LC-PolScope was introduced as a modern version of the traditional polarizing microscope enhanced by liquid crystal devices for the control of polarization, and by electronic imaging and digital image processing for fast and comprehensive image acquisition and analysis. The LC-PolScope is commonly used for birefringence imaging, analyzing the spatial and temporal variations of the differential phase delay in ordered and transparent materials. Here we describe an alternative use of the LC-PolScope for imaging the polarization dependent transmittance of dichroic materials. We explain the minor changes needed to convert the instrument between the two imaging modes, discuss the relationship between the quantities measured with each instrument, and touch on the physical connection between refractive index, birefringence, transmittance, diattenuation, and dichroism. (special issue article)

  2. Phase-conjugate holographic system for high-resolution particle-image velocimetry

    International Nuclear Information System (INIS)

    Barnhart, D.H.; Adrian, R.J.; Papen, G.C.

    1994-01-01

    A novel holographic particle-image velocimeter system has been developed for the study of three-dimensional (3-D) fluid velocity fields. The recording system produces 3-D particle images with a resolution, a signal-to-noise ratio, an accuracy, and derived velocity fields that are comparable to high-quality two-dimensional photographic particle-image velocimetry (PIV). The high image resolution is accomplished through the use of low f-number optics, a fringe-stabilized processing chemistry, and a phase conjugate play-back geometry that compensates for aberrations in the imaging system. In addition, the system employs a reference multiplexed, off-axis geometry for the determination of velocity directions with the cross-correlation technique, and a stereo camera geometry for the determination of the three velocity components. The combination of the imaging and reconstruction subsystems makes the analysis of volumetric PIV domains feasible

  3. Phase-conjugate holographic system for high-resolution particle-image velocimetry.

    Science.gov (United States)

    Barnhart, D H; Adrian, R J; Papen, G C

    1994-10-20

    A novel holographic particle-image velocimeter system has been developed for the study of threedimensional (3-D) fluid velocity fields. The recording system produces 3-D particle images with a resolution, a signal-to-noise ratio, an accuracy, and derived velocity fields that are comparable to high-quality two-dimensional photographic particle-image velocimetry (PIV). The high image resolution is accomplished through the use of low f-number optics, a fringe-stabilized processing chemistry, and a phase conjugate play-back geometry that compensates for aberrations in the imaging system. In addition, the system employs a reference multiplexed, off-axis geometry for the determination of velocity directions with the cross-correlation technique, and a stereo camera geometry for the determination of the three velocity components. The combination of the imaging and reconstruction subsystems makes the analysis of volumetric PIV domains feasible.

  4. High-Resolution Longitudinal Screening with Magnetic Resonance Imaging in a Murine Brain Cancer Model

    Directory of Open Access Journals (Sweden)

    Nicholas A. Bock

    2003-11-01

    Full Text Available One of the main limitations of intracranial models of diseases is our present inability to monitor and evaluate the intracranial compartment noninvasively over time. Therefore, there is a growing need for imaging modalities that provide thorough neuropathological evaluations of xenograft and transgenic models of intracranial pathology. In this study, we have established protocols for multiple-mouse magnetic resonance imaging (MRI to follow the growth and behavior of intracranial xenografts of gliomas longitudinally. We successfully obtained weekly images on 16 mice for a total of 5 weeks on a 7-T multiple-mouse MRI. T2- and Ti-weighted imaging with gadolinium enhancement of vascularity was used to detect tumor margins, tumor size, and growth. These experiments, using 3D whole brain images obtained in four mice at once, demonstrate the feasibility of obtaining repeat radiological images in intracranial tumor models and suggest that MRI should be incorporated as a research modality for the investigation of intracranial pathobiology.

  5. High-resolution, high-throughput imaging with a multibeam scanning electron microscope.

    Science.gov (United States)

    Eberle, A L; Mikula, S; Schalek, R; Lichtman, J; Knothe Tate, M L; Zeidler, D

    2015-08-01

    Electron-electron interactions and detector bandwidth limit the maximal imaging speed of single-beam scanning electron microscopes. We use multiple electron beams in a single column and detect secondary electrons in parallel to increase the imaging speed by close to two orders of magnitude and demonstrate imaging for a variety of samples ranging from biological brain tissue to semiconductor wafers. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  6. Pre-clinical and Clinical Evaluation of High Resolution, Mobile Gamma Camera and Positron Imaging Devices

    Science.gov (United States)

    2010-10-01

    SCIENCE, VOL. 56, NO. 3, JUNE 2009 compact design with effective imaging closer to the edge of the camera. This will be advantageous for future PET ... effects in the F-18 ac- quisitions. REFERENCES [1] A. G. Weisenberger, S. Majewski, and D. Gilland et al., “Implementa- tion of a mobile, cardiac PET ...cardiac PET imaging in this environment is compensating for attenuation effects without the availability of transmission images. In this paper we

  7. High Resolution PET Imaging Probe for the Detection, Molecular Characterization and Treatment Monitoring of Prostate Cancer

    Science.gov (United States)

    2010-07-01

    Yoon Suk Huh, Seung Han Shin, Hyun Keong Lim, Dae Shik Kim , and Han Byul Jin, MR Compatible Brain PET Using Tileable GAPD Arrays. 2009 IEEE Nuclear...Intraoperative Imaging, Gargano-Mattinata, Italy, Aug. 28–30, 2009 (Invited) 2. Huh SS, Han L, Rogers WL, Clinthorne NH: Real time image...RSTD, October 19-25, 2008, Dresden, Germany 4. Sam S. Huh, Li Han , W. L. Rogers, and N. H. Clinthorne, “Real Time Image Reconstruction Using GPUs

  8. Post-mortem computed tomography: Technical principles and recommended parameter settings for high-resolution imaging.

    Science.gov (United States)

    Gascho, Dominic; Thali, Michael J; Niemann, Tilo

    2018-01-01

    Post-mortem computed tomography (PMCT) has become a standard procedure in many forensic institutes worldwide. However, the standard scan protocols offered by vendors are optimised for clinical radiology and its main considerations regarding computed tomography (CT), namely, radiation exposure and motion artefacts. Thus, these protocols aim at low-dose imaging and fast imaging techniques. However, these considerations are negligible in post-mortem imaging, which allows for significantly increased image quality. Therefore, the parameters have to be adjusted to achieve the best image quality. Several parameters affect the image quality differently and have to be weighed against each other to achieve the best image quality for different diagnostic interests. There are two main groups of parameters that are adjustable by the user: acquisition parameters and reconstruction parameters. Acquisition parameters have to be selected prior to scanning and affect the raw data composition. In contrast, reconstruction parameters affect the calculation of the slice stacks from the raw data. This article describes the CT principles from acquiring image data to post-processing and provides an overview of the significant parameters for increasing the image quality in PMCT. Based on the CT principles, the effects of these parameters on the contrast, noise, resolution and frequently occurring artefacts are described. This article provides a guide for the performance of PMCT in morgues, clinical facilities or private practices.

  9. [Study and design on Dyson imaging spectrometer in spectral broadband with high resolution].

    Science.gov (United States)

    Yan, Ling-Wei

    2014-04-01

    The paper designs and improves a telecentric imaging spectrometer, the Dyson imaging spectrometer. The optical structure of the imaging spectrometer is simple and compact, which is only composed of a hemispherical lens and a concave grating. Based on the Rowland circle and refraction theory, the broadband anastigmatic imaging condition of Dyson imaging spectrometer which is the ratio of the grating radius and hemispherical lens radius has been analyzed. By imposing this condition for two different wavelengths, the parameters of the optical system presenting low aberrations and excellent imaging quality are obtained. To make the design spectrometer more suitable for the engineering application, the paper studies the method making the detector not to attach the surface of the hemispherical lens. A design example using optimal conditions was designed to prove our theory. The Dyson imaging spectrometer of which the imaging RMS radii are less than 2.5 microm and the advanced spectrometer of which the imaging RMS radii are less than 8 microm, with NA 0.33, waveband 0.38-1.7 microm and the slit length 15 mm, have been obtained. The design method and results are more feasible and predominant, and can be applied in the areas of the industry and remote sensing.

  10. New views of the human NK cell immunological synapse: recent advances enabled by super- and high- resolution imaging techniques

    Directory of Open Access Journals (Sweden)

    Emily M. Mace

    2013-01-01

    Full Text Available Imaging technology has undergone rapid growth with the development of super resolution microscopy, which enables resolution below the diffraction barrier of light (~200 nm. In addition, new techniques for single molecule imaging are being added to the cell biologist’s arsenal. Immunologists have exploited these techniques to advance understanding of NK biology, particularly that of the immune synapse. The immune synapse’s relatively small size and complex architecture combined with its exquisitely controlled signaling milieu have made it a challenge to visualize. In this review we highlight and discuss new insights into NK cell immune synapse formation and regulation revealed by cutting edge imaging techniques, including super resolution microscopy and high resolution total internal reflection microscopy and Förster resonance energy transfer.

  11. Non-contact high resolution Bessel beam probe for diagnostic imaging of cornea and trabecular meshwork region in eye

    Science.gov (United States)

    Murukeshan, V. M.; Jesmond, Hong Xun J.; Shinoj, V. K.; Baskaran, M.; Tin, Aung

    2015-07-01

    Primary angle closure glaucoma is a major form of disease that causes blindness in Asia and worldwide. In glaucoma, irregularities in the ocular aqueous outflow system cause an elevation in intraocular pressure (IOP) with subsequent death of retinal ganglion cells, resulting in loss of vision. High resolution visualization of the iridocorneal angle region has great diagnostic value in understanding the disease condition which enables monitoring of surgical interventions that decrease IOP. None of the current diagnostic techniques such as goniophotography, ultrasound biomicroscopy (UBM), anterior segment optical coherence tomography (AS-OCT) and RetCam™ can image with molecular specificity and required spatial resolution that can delineate the trabecular meshwork structures. This paper in this context proposes new concepts and methodology using Bessel beams based illumination and imaging for such diagnostic ocular imaging applications. The salient features using Bessel beams instead of the conventional Gaussian beam, and the optimization challenges in configuring the probe system will be illustrated with porcine eye samples.

  12. Land-use Scene Classification in High-Resolution Remote Sensing Images by Multiscale Deeply Described Correlatons

    Science.gov (United States)

    Qi, K.; Qingfeng, G.

    2017-12-01

    With the popular use of High-Resolution Satellite (HRS) images, more and more research efforts have been placed on land-use scene classification. However, it makes the task difficult with HRS images for the complex background and multiple land-cover classes or objects. This article presents a multiscale deeply described correlaton model for land-use scene classification. Specifically, the convolutional neural network is introduced to learn and characterize the local features at different scales. Then, learnt multiscale deep features are explored to generate visual words. The spatial arrangement of visual words is achieved through the introduction of adaptive vector quantized correlograms at different scales. Experiments on two publicly available land-use scene datasets demonstrate that the proposed model is compact and yet discriminative for efficient representation of land-use scene images, and achieves competitive classification results with the state-of-art methods.

  13. High-Resolution Spin-on-Patterning of Perovskite Thin Films for a Multiplexed Image Sensor Array.

    Science.gov (United States)

    Lee, Woongchan; Lee, Jongha; Yun, Huiwon; Kim, Joonsoo; Park, Jinhong; Choi, Changsoon; Kim, Dong Chan; Seo, Hyunseon; Lee, Hakyong; Yu, Ji Woong; Lee, Won Bo; Kim, Dae-Hyeong

    2017-10-01

    Inorganic-organic hybrid perovskite thin films have attracted significant attention as an alternative to silicon in photon-absorbing devices mainly because of their superb optoelectronic properties. However, high-definition patterning of perovskite thin films, which is important for fabrication of the image sensor array, is hardly accomplished owing to their extreme instability in general photolithographic solvents. Here, a novel patterning process for perovskite thin films is described: the high-resolution spin-on-patterning (SoP) process. This fast and facile process is compatible with a variety of spin-coated perovskite materials and perovskite deposition techniques. The SoP process is successfully applied to develop a high-performance, ultrathin, and deformable perovskite-on-silicon multiplexed image sensor array, paving the road toward next-generation image sensor arrays. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. A high resolution Small Field Of View (SFOV) gamma camera: a columnar scintillator coated CCD imager for medical applications

    Science.gov (United States)

    Lees, J. E.; Bassford, D. J.; Blake, O. E.; Blackshaw, P. E.; Perkins, A. C.

    2011-12-01

    We describe a high resolution, small field of view (SFOV), Charge Coupled Device (CCD) based camera for imaging small volumes of radionuclide uptake in tissues. The Mini Gamma Ray Camera (MGRC) is a collimated, scintillator-coated, low cost, high performance imager using low noise CCDs. The prototype MGRC has a 600 μm thick layer of columnar CsI(Tl) and operates in photon counting mode using a thermoelectric cooler to achieve an operating temperature of - 10°C. Collimation was performed using a pin hole collimator. We have measured the spatial resolution, energy resolution and efficiency using a number of radioisotope sources including 140 keV gamma-rays from 99mTc in a specially designed phantom. We also describe our first imaging of a volunteer patient.

  15. Can high-resolution peripheral quantitative computed tomography imaging of subchondral and cortical bone predict condylar fracture in Thoroughbred racehorses?

    Science.gov (United States)

    Trope, G D; Ghasem-Zadeh, A; Anderson, G A; Mackie, E J; Whitton, R C

    2015-07-01

    High-resolution 3D imaging may improve the prediction and/or early identification of condylar fractures of the distal metacarpus/tarsus and reduce the frequency of breakdown injury in racehorses. To test the hypotheses that horses suffering condylar fractures have higher bone volume fraction (BV/TV) of the distal metacarpal epiphysis, greater subchondral bone thickness at the fracture site and higher second moment of inertia in the metacarpal midshaft as identified with high-resolution 3D imaging. Cross-sectional study using cadaver material. Thoroughbreds that died on racetracks were grouped as: 1) horses with third metacarpal (McIII) fractures with a condylar component (cases, n = 13); 2) horses with no limb fracture (controls, n = 8); 3) horses with fractures in other bones or suspensory apparatus disruption (other fatal injuries, n = 16). The palmar condyles of McIII and the midshaft were examined with high resolution peripheral quantitative computed tomography (HR-pQCT). Statistical analysis included logistic regression and Spearman's correlation. There were no significant differences in BV/TV of distal McIII and second moment of inertia of the midshaft between cases and controls. Epiphyseal bone BV/TV was greater in injured limbs of horses with any fatal limb injury (Groups 1 and 3 combined) compared with controls (odds ratio = 1.20, 95% confidence interval 1.01-1.42, P = 0.034). An epiphyseal BV/TV>0.742 resulted in a sensitivity of 82.8% and specificity of 62.5% in identifying horses with fatal limb injury. In horses without condylar fracture, increased subchondral bone thickness was associated with palmar osteochondral disease lesions in the adjacent condyle (rs = 0.65, Phorses at risk of any fatal breakdown injury but not metacarpal condylar fractures. Measurement of parasagittal groove subchondral bone thickness is complicated by adjacent palmar osteochondral disease lesions. Thus, high-resolution imaging of the distal metacarpus appears to have limited

  16. Potentials of high resolution magnetic resonance imaging versus computed tomography for preoperative local staging of colon cancer

    International Nuclear Information System (INIS)

    Rollven, Erik; Blomqvist, Lennart; Holm, Torbjorn; Glimelius, Bengt; Loerinc, Esther

    2013-01-01

    Background: Preoperative identification of locally advanced colon cancer is of importance in order to properly plan treatment. Purpose: To study high resolution T2-weighted magnetic resonance imaging (MRI) versus computed tomography (CT) for preoperative staging of colon cancer with surgery and histopathology as reference standard. Material and Methods: Twenty-eight patients with a total of 29 tumors were included. Patients were examined on a 1.5 T MR unit using a phased array body coil. T2 turbo spin-echo high resolution sequences were obtained in a coronal, transverse, and perpendicular plane to the long axis of the colon at the site of the tumor. Contrast-enhanced CT was performed using a protocol for metastasis staging. The examinations were independently evaluated by two gastrointestinal radiologists using criteria adapted to imaging for prediction of T-stage, N-stage, and extramural venous invasion. Based on the T-stage, tumors were divided in to locally advanced (T3cd-T4) and not locally advanced (T1-T3ab). Surgical and histopathological findings served as reference standard. Results: Using MRI, T-stage, N-stage, and extramural venous invasion were correctly predicted for each observer in 90% and 93%, 72% and 69%, and 82% and 78% of cases, respectively. With CT the corresponding results were 79% and 76%, 72% and 72%, 78% and 67%. For MRI inter-observer agreements (Kappa statistics) were 0.79, 0.10, and 0.76. For CT the corresponding results were 0.64, 0.66, and 0.22. Conclusion: Patients with locally advanced colon cancer, defined as tumor stage T3cd-T4, can be identified by both high resolution MRI and CT, even when CT is performed with a metastasis staging protocol. MRI may have an advantage, due to its high soft tissue discrimination, to identify certain prognostic factors such as T-stage and extramural venous invasion

  17. Potentials of high resolution magnetic resonance imaging versus computed tomography for preoperative local staging of colon cancer

    Energy Technology Data Exchange (ETDEWEB)

    Rollven, Erik; Blomqvist, Lennart [Dept. of Diagnostic Radiology, Karolinska Univ. Hospital Solna, Stockholm (Sweden); Dept. of Molecular Medicine and Surgery, Karolinska Inst., Stockholm (Sweden)], e-mail: erik.rollven@ki.se; Holm, Torbjorn [Dept. of Molecular Medicine and Surgery, Karolinska Inst., Stockholm (Sweden); Dept. of Surgery, Karolinska Univ. Hospital Solna, Stockholm (Sweden); Glimelius, Bengt [Dept. of Radiology, Oncology and Radiation Science, Uppsala Univ., Uppsala (Sweden); Dept. of Oncology and Pathology, Karolinska Inst., Stockholm (Sweden); Loerinc, Esther [Dept. of Oncology and Pathology, Karolinska Inst., Stockholm (Sweden); Dept. of Pathology, Karolinska Univ. Hospital, Solna, Sweden (Sweden)

    2013-09-15

    Background: Preoperative identification of locally advanced colon cancer is of importance in order to properly plan treatment. Purpose: To study high resolution T2-weighted magnetic resonance imaging (MRI) versus computed tomography (CT) for preoperative staging of colon cancer with surgery and histopathology as reference standard. Material and Methods: Twenty-eight patients with a total of 29 tumors were included. Patients were examined on a 1.5 T MR unit using a phased array body coil. T2 turbo spin-echo high resolution sequences were obtained in a coronal, transverse, and perpendicular plane to the long axis of the colon at the site of the tumor. Contrast-enhanced CT was performed using a protocol for metastasis staging. The examinations were independently evaluated by two gastrointestinal radiologists using criteria adapted to imaging for prediction of T-stage, N-stage, and extramural venous invasion. Based on the T-stage, tumors were divided in to locally advanced (T3cd-T4) and not locally advanced (T1-T3ab). Surgical and histopathological findings served as reference standard. Results: Using MRI, T-stage, N-stage, and extramural venous invasion were correctly predicted for each observer in 90% and 93%, 72% and 69%, and 82% and 78% of cases, respectively. With CT the corresponding results were 79% and 76%, 72% and 72%, 78% and 67%. For MRI inter-observer agreements (Kappa statistics) were 0.79, 0.10, and 0.76. For CT the corresponding results were 0.64, 0.66, and 0.22. Conclusion: Patients with locally advanced colon cancer, defined as tumor stage T3cd-T4, can be identified by both high resolution MRI and CT, even when CT is performed with a metastasis staging protocol. MRI may have an advantage, due to its high soft tissue discrimination, to identify certain prognostic factors such as T-stage and extramural venous invasion.

  18. High resolution MR imaging of pelvic lymph nodes at 7 Tesla

    NARCIS (Netherlands)

    Philips, B.W.J.; Fortuin, A.S.; Orzada, S.; Scheenen, T.W.J.; Maas, M.C.

    2017-01-01

    PURPOSE: Pelvic lymph node (PLN) metastases are often smaller than 5 mm and difficult to detect. This work presents a method to perform PLN imaging with ultrahigh-field MRI, using spectrally selective excitation to acquire water and lipid-selective imaging at high spatial resolution. METHODS: A 3D

  19. Costless Platform for High Resolution Stereoscopic Images of a High Gothic Facade

    Science.gov (United States)

    Héno, R.; Chandelier, L.; Schelstraete, D.

    2012-07-01

    In October 2011, the PPMD specialized master's degree students (Photogrammetry, Positionning and Deformation Measurement) of the French ENSG (IGN's School of Geomatics, the Ecole Nationale des Sciences Géographiques) were asked to come and survey the main facade of the cathedral of Amiens, which is very complex as far as size and decoration are concerned. Although it was first planned to use a lift truck for the image survey, budget considerations and taste for experimentation led the project to other perspectives: images shot from the ground level with a long focal camera will be combined to complementary images shot from what higher galleries are available on the main facade with a wide angle camera fixed on a horizontal 2.5 meter long pole. This heteroclite image survey is being processed by the PPMD master's degree students during this academic year. Among other type of products, 3D point clouds will be calculated on specific parts of the facade with both sources of images. If the proposed device and methodology to get full image coverage of the main facade happen to be fruitful, the image acquisition phase will be completed later by another team. This article focuses on the production of 3D point clouds with wide angle images on the rose of the main facade.

  20. COSTLESS PLATFORM FOR HIGH RESOLUTION STEREOSCOPIC IMAGES OF A HIGH GOTHIC FACADE

    Directory of Open Access Journals (Sweden)

    R. Héno

    2012-07-01

    Full Text Available In October 2011, the PPMD specialized master's degree students (Photogrammetry, Positionning and Deformation Measurement of the French ENSG (IGN’s School of Geomatics, the Ecole Nationale des Sciences Géographiques were asked to come and survey the main facade of the cathedral of Amiens, which is very complex as far as size and decoration are concerned. Although it was first planned to use a lift truck for the image survey, budget considerations and taste for experimentation led the project to other perspectives: images shot from the ground level with a long focal camera will be combined to complementary images shot from what higher galleries are available on the main facade with a wide angle camera fixed on a horizontal 2.5 meter long pole. This heteroclite image survey is being processed by the PPMD master's degree students during this academic year. Among other type of products, 3D point clouds will be calculated on specific parts of the facade with both sources of images. If the proposed device and methodology to get full image coverage of the main facade happen to be fruitful, the image acquisition phase will be completed later by another team. This article focuses on the production of 3D point clouds with wide angle images on the rose of the main facade.

  1. Study of CT-based positron range correction in high resolution 3D PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cal-Gonzalez, J., E-mail: jacobo@nuclear.fis.ucm.es [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Herraiz, J.L. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Espana, S. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Vicente, E. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain); Herranz, E. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Desco, M. [Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Vaquero, J.J. [Dpto. de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Udias, J.M. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain)

    2011-08-21

    Positron range limits the spatial resolution of PET images and has a different effect for different isotopes and positron propagation materials. Therefore it is important to consider it during image reconstruction, in order to obtain optimal image quality. Positron range distributions for most common isotopes used in PET in different materials were computed using the Monte Carlo simulations with PeneloPET. The range profiles were introduced into the 3D OSEM image reconstruction software FIRST and employed to blur the image either in the forward projection or in the forward and backward projection. The blurring introduced takes into account the different materials in which the positron propagates. Information on these materials may be obtained, for instance, from a segmentation of a CT image. The results of introducing positron blurring in both forward and backward projection operations was compared to using it only during forward projection. Further, the effect of different shapes of positron range profile in the quality of the reconstructed images with positron range correction was studied. For high positron energy isotopes, the reconstructed images show significant improvement in spatial resolution when positron range is taken into account during reconstruction, compared to reconstructions without positron range modeling.

  2. Non-Invasive Imaging of Neuroanatomical Structures and Neural Activation with High-Resolution MRI

    Science.gov (United States)

    Herberholz, Jens; Mishra, Subrata H.; Uma, Divya; Germann, Markus W.; Edwards, Donald H.; Potter, Kimberlee

    2011-01-01

    Several years ago, manganese-enhanced magnetic resonance imaging (MEMRI) was introduced as a new powerful tool to image active brain areas and to identify neural connections in living, non-human animals. Primarily restricted to studies in rodents and later adapted for bird species, MEMRI has recently been discovered as a useful technique for neuroimaging of invertebrate animals. Using crayfish as a model system, we highlight the advantages of MEMRI over conventional techniques for imaging of small nervous systems. MEMRI can be applied to image invertebrate nervous systems at relatively high spatial resolution, and permits identification of stimulus-evoked neural activation non-invasively. Since the selection of specific imaging parameters is critical for successful in vivo micro-imaging, we present an overview of different experimental conditions that are best suited for invertebrates. We also compare the effects of hardware and software specifications on image quality, and provide detailed descriptions of the steps necessary to prepare animals for successful imaging sessions. Careful consideration of hardware, software, experiments, and specimen preparation will promote a better understanding of this novel technique and facilitate future MEMRI studies in other laboratories. PMID:21503138

  3. The design of a novel tip enhanced near-field scanning probe microscope for ultra-high resolution optical imaging

    Science.gov (United States)

    Nowak, Derek Brant

    Traditional light microscopy suffers from the diffraction limit, which limits the spatial resolution to lambda/2. The current trend in optical microscopy is the development of techniques to bypass the diffraction limit. Resolutions below 40 nm will make it possible to probe biological systems by imaging the interactions between single molecules and cell membranes. These resolutions will allow for the development of improved drug delivery mechanisms by increasing our understanding of how chemical communication within a cell occurs. The materials sciences would also benefit from these high resolutions. Nanomaterials can be analyzed with Raman spectroscopy for molecular and atomic bond information, or with fluorescence response to determine bulk optical properties with tens of nanometer resolution. Near-field optical microscopy is one of the current techniques, which allows for imaging at resolutions beyond the diffraction limit. Using a combination of a shear force microscope (SFM) and an inverted optical microscope, spectroscopic resolutions below 20 nm have been demonstrated. One technique, in particular, has been named tip enhanced near-field optical microscopy (TENOM). The key to this technique is the use of solid metal probes, which are illuminated in the far field by the excitation wavelength of interest. These probes are custom-designed using finite difference time domain (FDTD) modeling techniques, then fabricated with the use of a focused ion beam (FIB) microscope. The measure of the quality of probe design is based directly on the field enhancement obtainable. The greater the field enhancement of the probe, the more the ratio of near-field to far-field background contribution will increase. The elimination of the far-field signal by a decrease of illumination power will provide the best signal-to-noise ratio in the near-field images. Furthermore, a design that facilitates the delocalization of the near-field imaging from the far-field will be beneficial

  4. High-resolution 3-D imaging of living cells in suspension using confocal axial tomography.

    Science.gov (United States)

    Renaud, Olivier; Viña, Jose; Yu, Yong; Machu, Christophe; Trouvé, Alain; Van der Voort, Hans; Chalmond, Bernard; Shorte, Spencer L

    2008-01-01

    Conventional flow cytometry (FC) methods report optical signals integrated from individual cells at throughput rates as high as thousands of cells per second. This is further combined with the powerful utility to subsequently sort and/or recover the cells of interest. However, these methods cannot extract spatial information. This limitation has prompted efforts by some commercial manufacturers to produce state-of-the-art commercial flow cytometry systems allowing fluorescence images to be recorded by an imaging detector. Nonetheless, there remains an immediate and growing need for technologies facilitating spatial analysis of fluorescent signals from cells maintained in flow suspension. Here, we report a novel methodological approach to this problem that combines micro-fluidic flow, and microelectrode dielectric-field control to manipulate, immobilize and image individual cells in suspension. The method also offers unique possibilities for imaging studies on cells in suspension. In particular, we report the system's immediate utility for confocal "axial tomography" using micro-rotation imaging and show that it greatly enhances 3-D optical resolution compared with conventional light reconstruction (deconvolution) image data treatment. That the method we present here is relatively rapid and lends itself to full automation suggests its eventual utility for 3-D imaging cytometry.

  5. High-resolution wavelet-fractal compressed optical coherence tomography images.

    Science.gov (United States)

    Faiza, Mekhalfa; Adabi, Saba; Daoud, Berkani; Avanaki, Mohammad R N

    2017-02-01

    Three-dimensional (3D) optical coherence tomography (OCT) images could assist specialists in the diagnosis of a disease in a tissue by providing morphological information from it. Since the size of such images is usually extremely large, an appropriate image compression method can help in the storage and transmission of these images. Fractal image compression provides very high compression ratios, and discrete wavelet transform (DWT) retains frequency and spatial information in the signal. In order to combine these two techniques, fractal coding has to be performed in the wavelet domain. In this work, we propose a three-dimensional extension version of the wavelet-fractal coding algorithm. The use of 3D fractal approximation to encode 3D wavelet coefficients allows us to exploit inter- and intra-redundancy of the image sequences. The compression results of several OCT images using the 3D wavelet-fractal algorithm are evaluated qualitatively and quantitatively and are compared with the results of the two-dimensional approach. The numerical results illustrate the superior performance of 3D wavelet-fractal algorithm in terms of compression ratio.

  6. Ultra high resolution tomography

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  7. Mission Concepts for High-Resolution Solar Imaging with a Photon Sieve

    Science.gov (United States)

    Rabin, Douglas M.; Davila, Joseph; Daw, Adrian N.; Denis, Kevin L.; Novo-Gradac, Anne-Marie; Shah, Neerav; Widmyer, Thomas R.

    2017-08-01

    The best EUV coronal imagers are unable to probe the expected energy dissipation scales of the solar corona (sieve, a diffractive imaging element similar to a Fresnel zone plate, provides a technically feasible path to the required angular resolution. We have produced photon sieves as large as 80 mm clear aperture. We discuss laboratory measurements of these devices and the path to larger apertures. The focal length of a sieve with high EUV resolution is at least 10 m. Options for solar imaging with such a sieve include a sounding rocket, a single spacecraft with a deployed boom, and two spacecraft flying in precise formation.

  8. High-resolution low-field molecular magnetic resonance imaging of hyperpolarized liquids.

    Science.gov (United States)

    Coffey, Aaron M; Kovtunov, Kirill V; Barskiy, Danila A; Koptyug, Igor V; Shchepin, Roman V; Waddell, Kevin W; He, Ping; Groome, Kirsten A; Best, Quinn A; Shi, Fan; Goodson, Boyd M; Chekmenev, Eduard Y

    2014-09-16

    We demonstrate the feasibility of microscale molecular imaging using hyperpolarized proton and carbon-13 MRI contrast media and low-field (47.5 mT) preclinical scale (38 mm i.d.) 2D magnetic resonance imaging (MRI). Hyperpolarized proton images with 94 × 94 μm(2) spatial resolution and hyperpolarized carbon-13 images with 250 × 250 μm(2) in-plane spatial resolution were recorded in 4-8 s (largely limited by the electronics response), surpassing the in-plane spatial resolution (i.e., pixel size) achievable with micro-positron emission tomography (PET). These hyperpolarized proton and (13)C images were recorded using large imaging matrices of up to 256 × 256 pixels and relatively large fields of view of up to 6.4 × 6.4 cm(2). (13)C images were recorded using hyperpolarized 1-(13)C-succinate-d2 (30 mM in water, %P(13C) = 25.8 ± 5.1% (when produced) and %P(13C) = 14.2 ± 0.7% (when imaged), T1 = 74 ± 3 s), and proton images were recorded using (1)H hyperpolarized pyridine (100 mM in methanol-d4, %P(H) = 0.1 ± 0.02% (when imaged), T1 = 11 ± 0.1 s). Both contrast agents were hyperpolarized using parahydrogen (>90% para-fraction) in an automated 5.75 mT parahydrogen induced polarization (PHIP) hyperpolarizer. A magnetized path was demonstrated for successful transportation of a (13)C hyperpolarized contrast agent (1-(13)C-succinate-d2, sensitive to fast depolarization when at the Earth's magnetic field) from the PHIP polarizer to the 47.5 mT low-field MRI. While future polarizing and low-field MRI hardware and imaging sequence developments can further improve the low-field detection sensitivity, the current results demonstrate that microscale molecular imaging in vivo is already feasible at low (<50 mT) fields and potentially at low (~1 mM) metabolite concentrations.

  9. Role and Correlation of High Resolution Ultrasound and Magnetic Resonance Imaging in Evaluation of Patients with Shoulder Pain.

    Science.gov (United States)

    Singh, Amandeep; Thukral, Chuni Lal; Gupta, Kamlesh; Singh, Mahesh Inder; Lata, Sneh; Arora, Ram Krishan

    2017-01-01

    The study aimed to evaluate of the role of high-resolution ultrasound and magnetic resonance imaging in patients with shoulder pain. This prospective study included 50 patients referred for ultrasound and MRI because of shoulder pain. All patients were examined clinically, followed by radiography of the affected shoulder. High-resolution ultrasound examination of the involved shoulder was performed together with an examination of the contralateral normal shoulder, followed by MRI of the symptomatic shoulder in all 50 patients. In the present study, the majority of patients were in age group 56-65 years, 56% were males and 44% were females (of a total of 50 patients). A total of 40 patients were diagnosed as having rotator cuff tears on ultrasound (USG) and MRI. USG showed complete-thickness tears in 25 patients and partial-thickness tears in 15 patients. MRI detected 28 complete- and 12 partial-thickness tears of the rotator cuff. In the diagnosis of rotator cuff tears, the strength of agreement between ultrasound and magnetic resonance imaging was good (kappa coefficient=0.79). Ultrasonography of the shoulder shows promising results in the diagnosis of rotator cuff tears and in differentiating partial from complete tears. A wide availability, cost effectiveness and better tolerability of ultrasonography make it a modality of first choice for evaluating rotator cuff tears.

  10. Characterisation of carotid plaques with ultrasound elastography: feasibility and correlation with high-resolution magnetic resonance imaging

    International Nuclear Information System (INIS)

    Naim, Cyrille; Cloutier, Guy; Mercure, Elizabeth; Destrempes, Francois; Qin, Zhao; El-Abyad, Walid; Lanthier, Sylvain; Giroux, Marie-France; Soulez, Gilles

    2013-01-01

    To evaluate the ability of ultrasound non-invasive vascular elastography (NIVE) strain analysis to characterise carotid plaque composition and vulnerability as determined by high-resolution magnetic resonance imaging (MRI). Thirty-one subjects with 50 % or greater carotid stenosis underwent NIVE and high-resolution MRI of internal carotid arteries. Time-varying strain images (elastograms) of segmented plaques were generated from ultrasonic raw radiofrequency sequences. On MRI, corresponding plaques and components were segmented and quantified. Associations between strain parameters, plaque composition and symptomatology were estimated with curve-fitting regressions and Mann-Whitney tests. Mean stenosis and age were 72.7 % and 69.3 years, respectively. Of 31 plaques, 9 were symptomatic, 17 contained lipid and 7 were vulnerable on MRI. Strains were significantly lower in plaques containing a lipid core compared with those without lipid, with 77-100 % sensitivity and 57-79 % specificity (P < 0.032). A statistically significant quadratic fit was found between strain and lipid content (P < 0.03). Strains did not discriminate symptomatic patients or vulnerable plaques. Ultrasound NIVE is feasible in patients with significant carotid stenosis and can detect the presence of a lipid core with high sensitivity and moderate specificity. Studies of plaque progression with NIVE are required to identify vulnerable plaques. (orig.)

  11. Road Extraction from High-Resolution SAR Images via Automatic Local Detecting and Human-Guided Global Tracking

    Directory of Open Access Journals (Sweden)

    Jianghua Cheng

    2012-01-01

    Full Text Available Because of existence of various kinds of disturbances, layover effects, and shadowing, it is difficult to extract road from high-resolution SAR images. A new road center-point searching method is proposed by two alternant steps: local detection and global tracking. In local detection step, double window model is set, which consists of the outer fixed square window and the inner rotary rectangular one. The outer window is used to obtain the local road direction by using orientation histogram, based on the fact that the surrounding objects always range along with roads. The inner window rotates its orientation in accordance with the result of local road direction calculation and searches the center points of a road segment. In global tracking step, particle filter of variable-step is used to deal with the problem of tracking frequently broken by shelters along the roadside and obstacles on the road. Finally, the center-points are linked by quadratic curve fitting. In 1 m high-resolution airborne SAR image experiment, the results show that this method is effective.

  12. High-resolution morphologic and ultrashort time-to-echo quantitative magnetic resonance imaging of the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Won C.; Chang, Eric Y.; Biswas, Reni; Statum, Sheronda; Chung, Christine B. [Veterans Administration San Diego Healthcare System, Department of Radiology, San Diego, CA (United States); University of California, San Diego, School of Medicine, Department of Radiology, San Diego, CA (United States); Tafur, Monica; Du, Jiang; Healey, Robert [University of California, San Diego, School of Medicine, Department of Radiology, San Diego, CA (United States); Kwack, Kyu-Sung [Ajou University Medical Center, Department of Radiology, Wonchon-dong, Yeongtong-gu, Gyeonggi-do, Suwon (Korea, Republic of)

    2016-03-15

    To implement high-resolution morphologic and quantitative magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) using ultrashort time-to-echo (UTE) techniques in cadavers and volunteers. This study was approved by the institutional review board. TMJs of cadavers and volunteers were imaged on a 3-T MR system. High-resolution morphologic and quantitative sequences using conventional and UTE techniques were performed in cadaveric TMJs. Morphologic and UTE quantitative sequences were performed in asymptomatic and symptomatic volunteers. Morphologic evaluation demonstrated the TMJ structures in open- and closed-mouth position. UTE techniques facilitated the visualization of the disc and fibrocartilage. Quantitative UTE MRI was successfully performed ex vivo and in vivo, reflecting the degree of degeneration. There was a difference in the mean UTE T2* values between asymptomatic and symptomatic volunteers. MRI evaluation of the TMJ using UTE techniques allows characterization of the internal structure and quantification of the MR properties of the disc. Quantitative UTE MRI can be performed in vivo with short scan times. (orig.)

  13. High-resolution subsurface imaging and neural network recognition: Non-intrusive buried substance location. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sternberg, B.K.; Poulton, M.M.

    1997-01-26

    A high-frequency, high-resolution electromagnetic (EM) imaging system has been developed for environmental geophysics surveys. Some key features of this system include: (1) rapid surveying to allow dense spatial sampling over a large area, (2) high-accuracy measurements which are used to produce a high-resolution image of the subsurface, (3) measurements which have excellent signal-to-noise ratio over a wide bandwidth (31 kHz to 32 MHz), (4) elimination of electric-field interference at high frequencies, (5) large-scale physical modeling to produce accurate theoretical responses over targets of interest in environmental geophysics surveys, (6) rapid neural network interpretation at the field site, and (7) visualization of complex structures during the survey. Four major experiments were conducted with the system: (1) Data were collected for several targets in our physical modeling facility. (2) The authors tested the system over targets buried in soil. (3) The authors conducted an extensive survey at the Idaho National Engineering Laboratory (INEL) Cold Test Pit (CTP). The location of the buried waste, category of waste, and thickness of the clay cap were successfully mapped. (4) The authors ran surveys over the acid pit at INEL. This was an operational survey over a hot site. The interpreted low-resistivity region correlated closely with the known extent of the acid pit.

  14. High-resolution subsurface imaging and neural network recognition: Non-intrusive buried substance location. Final report, January 26, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Sternberg, B.K.; Poulton, M.M.

    1998-12-31

    A high-frequency, high-resolution electromagnetic (EIVI) imaging system has been developed for environmental geophysics surveys. Some key features of this system include: (1) rapid surveying to allow dense spatial sampling over a large area, (2) high-accuracy measurements which are used to produce a high-resolution image of the subsurface, (3) measurements which have excellent signal-to-noise ratio over a wide bandwidth (31 kHz to 32 MHZ), (4) elimination of electric-field interference at high frequencies, (5) large-scale physical modeling to produce accurate theoretical responses over targets of interest in environmental geophysics surveys, (6) rapid neural network interpretation at the field site, and (7) visualization of complex structures during the survey. Four major experiments were conducted with the system: (1) Data were collected for several targets in our physical modeling facility. (2) We tested the system over targets buried in soil. (3) We conducted an extensive survey at the Idaho National Engineering Laboratory (INEL) Cold Test Pit (CTP). The location of the buried waste, category of waste, and thickness of the clay cap were successfully mapped. (4) We ran surveys over the acid pit at INEL. This was an operational survey over a hot site. The interpreted low-resistivity region correlated closely with the known extent of the acid pit.

  15. High-resolution subsurface imaging and neural network recognition: Non-intrusive buried substance location. Final report, January 26, 1997

    International Nuclear Information System (INIS)

    Sternberg, B.K.; Poulton, M.M.

    1998-01-01

    A high-frequency, high-resolution electromagnetic (EIVI) imaging system has been developed for environmental geophysics surveys. Some key features of this system include: (1) rapid surveying to allow dense spatial sampling over a large area, (2) high-accuracy measurements which are used to produce a high-resolution image of the subsurface, (3) measurements which have excellent signal-to-noise ratio over a wide bandwidth (31 kHz to 32 MHZ), (4) elimination of electric-field interference at high frequencies, (5) large-scale physical modeling to produce accurate theoretical responses over targets of interest in environmental geophysics surveys, (6) rapid neural network interpretation at the field site, and (7) visualization of complex structures during the survey. Four major experiments were conducted with the system: (1) Data were collected for several targets in our physical modeling facility. (2) We tested the system over targets buried in soil. (3) We conducted an extensive survey at the Idaho National Engineering Laboratory (INEL) Cold Test Pit (CTP). The location of the buried waste, category of waste, and thickness of the clay cap were successfully mapped. (4) We ran surveys over the acid pit at INEL. This was an operational survey over a hot site. The interpreted low-resistivity region correlated closely with the known extent of the acid pit

  16. High resolution radio-imager for biology and micro-dosimetry

    International Nuclear Information System (INIS)

    Aubineau-Laniece, I.; Charon, Y.; Laniece, P.; Mastrippolito, R.; Pinot, L.; Valentin, L.

    1999-01-01

    We have developed a self triggered intensified CCD (STIC) for real time high spatial resolution a and b imaging. This device is, in particular, of great interest for quantitative autoradiography of radiolabeled biochemical species with low level activity. (authors)

  17. High Resolution X-Ray Phase Contrast Imaging with Acoustic Tissue-Selective Contrast Enhancement

    National Research Council Canada - National Science Library

    Diebold, Gerald J

    2005-01-01

    .... Interfacial features of objects are highlighted as a result of both the displacement introduced by the ultrasound and the inherent sensitivity of x-ray phase contrast imaging to density variations...

  18. High Resolution X-Ray Phase Contrast Imaging With Acoustic Tissue-Selective Contrast Enhancement

    National Research Council Canada - National Science Library

    Diebold, Gerald J

    2006-01-01

    .... Interfacial features of objects are highlighted as a result of both the displacement introduced by the ultrasound and the inherent sensitivity of x-ray phase contrast imaging to density variations...

  19. Vehicle detection from high-resolution aerial images based on superpixel and color name features

    Science.gov (United States)

    Chen, Ziyi; Cao, Liujuan; Yu, Zang; Chen, Yiping; Wang, Cheng; Li, Jonathan

    2016-03-01

    Automatic vehicle detection from aerial images is emerging due to the strong demand of large-area traffic monitoring. In this paper, we present a novel framework for automatic vehicle detection from the aerial images. Through superpixel segmentation, we first segment the aerial images into homogeneous patches, which consist of the basic units during the detection to improve efficiency. By introducing the sparse representation into our method, powerful classification ability is achieved after the dictionary training. To effectively describe a patch, the Histogram of Oriented Gradient (HOG) is used. We further propose to integrate color information to enrich the feature representation by using the color name feature. The final feature consists of both HOG and color name based histogram, by which we get a strong descriptor of a patch. Experimental results demonstrate the effectiveness and robust performance of the proposed algorithm for vehicle detection from aerial images.

  20. Laser Tweezer Controlled Solid Immersion Lens for High Resolution Imaging in Microfluidic and Biological Samples

    National Research Council Canada - National Science Library

    Birkbeck, Aaron L; Zlatanovic, Sanja; Ozkan, Mihrimah; Esener, Sadik C

    2005-01-01

    ...). Up to now, solid immersion lens imaging systems have relied upon cantilever-mounted SILs that are difficult to integrate into microfluidic systems and require an extra alignment step with external optics...

  1. Laser Tweezer Controlled Solid Immersion Lens for High Resolution Imaging in Microfluidic and Biological Samples

    National Research Council Canada - National Science Library

    Birkbeck, Aaron L; Zlatanovic, Sanja; Ozkan, Mihrimah; Esener, Sadik C

    2005-01-01

    A novel technique is presented which integrates the capacity of a laser tweezer to optically trap and manipulate objects in three-dimensions with the resolution-enhanced imaging capabilities of a solid immersion lens (SIL...

  2. High-resolution imaging of neural anatomy and pathology of the neck

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Hyun; Choi, Young Jun; Baek, Jung Hwan [Dept. of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Cheng, Kai Lung [Dept. of Medical Imaging, Chung Shan Medical University Hospital, Taichung (China)

    2017-01-15

    The neck has intricately connected neural structures, including cervical and brachial plexi, the sympathetic system, lower cranial nerves, and their branches. Except for brachial plexus, there has been little research regarding the normal imaging appearance or corresponding pathologies of neural structures in the neck. The development in imaging techniques with better spatial resolution and signal-to-noise ratio has made it possible to see many tiny nerves to predict complications related to image-guided procedures and to better assess treatment response, especially in the management of oncology patients. The purposes of this review is to present imaging-based anatomy of major nerves in the neck and explain their relevant clinical significance according to representative pathologies of regarded nerves in the neck.

  3. High resolution isotopic analysis of U-bearing particles via fusion of SIMS and EDS images

    Energy Technology Data Exchange (ETDEWEB)

    Tarolli, Jay G.; Naes, Benjamin E.; Garcia, Benjamin J.; Fischer, Ashley E.; Willingham, David

    2016-01-01

    Image fusion of secondary ion mass spectrometry (SIMS) images and X-ray elemental maps from energy-dispersive spectroscopy (EDS) was performed to facilitate the isolation and re-analysis of isotopically unique U-bearing particles where the highest precision SIMS measurements are required. Image registration, image fusion and particle micromanipulation were performed on a subset of SIMS images obtained from a large area pre-screen of a particle distribution from a sample containing several certified reference materials (CRM) U129A, U015, U150, U500 and U850, as well as a standard reference material (SRM) 8704 (Buffalo River Sediment) to simulate particles collected on swipes during routine inspections of declared uranium enrichment facilities by the International Atomic Energy Agency (IAEA). In total, fourteen particles, ranging in size from 5 – 15 µm, were isolated and re-analyzed by SIMS in multi-collector mode identifying nine particles of CRM U129A, one of U150, one of U500 and three of U850. These identifications were made within a few percent errors from the National Institute of Standards and Technology (NIST) certified atom percent values for 234U, 235U and 238U for the corresponding CRMs. This work represents the first use of image fusion to enhance the accuracy and precision of isotope ratio measurements for isotopically unique U-bearing particles for nuclear safeguards applications. Implementation of image fusion is essential for the identification of particles of interests that fall below the spatial resolution of the SIMS images.

  4. High Resolution PET Imaging Probe for the Detection, Molecular Characterization and Treatment Monitoring of Prostate Cancer

    Science.gov (United States)

    2012-07-01

    Champley, “The positron emission mammography/tomography breast imaging and biopsy system ( PEM /PET): design, construction and phantom-based...System for the Detection and Biopsy of Breast Cancer", Nuclear Instruments and Methods in Physics Research, A569 (2006),291-295. [4] Proffitt, J...Majewski, A. G. Weisenberger, D. A. Kieper, R. R. Raylman, and T. G. Turkington, "Analysis of factors affecting positron emission mammography ( PEM ) image

  5. MRO's High Resolution Imaging Science Experiment (HiRISE) Education And Public Outreach program

    Science.gov (United States)

    Gulick, V. C.; Davatzes, A.; McEwen, A.

    2006-12-01

    HiRISE provides an innovative education and public outreach program with a variety of formal and informal educational activities. The centerpiece of HiRISE's E/PO program is it's interactive website called HiWeb (http://marsoweb.nasa.nasa.gov/hirise and http://hirise.lpl.arizona.edu). HiWeb provides an image suggestion facility where the public can submit suggestions for HiRISE images and view HiRISE images in context with other available Mars data. HiRISE EPO has developed K-14 educational materials including activity, coloring and comic books that focus on Mars geology, the image suggestion process, understanding the HiRISE camera and working with digital image data. In addition, we have developed interactive educational games including Mars crosswords, jigsaws, word searches, and flash cards to provide fun ways for students to learn more about Mars. All educational materials and games are aligned with the National Science Standards. HiRISE Clickworkers will provide online opportunities for the public to assist the team in creating geologic feature databases (gullies, boulders, craters, wind streaks, etc.) present in the HiRISE images in addition to other innovative opportunities. Web events (including web chats, casts and forums) with HiRISE team members, will help guide students and educators of HiRISE capabilities and science goals and provide support for submitting good image suggestions. Educator workshops will be held each year at or near the institution of HiRISE team members. Workshop support materials and instructions for all hands-on activities will be placed on HiWeb to facilitate sharing of information with other educators and the general public. Large-scale displays of HiRISE images will be available at several at museums and planetariums.

  6. PRISM (processes research by an imaging spaceborne mission) high-resolution hyperspectral imager for scientific land processes monitoring applications

    Science.gov (United States)

    Kunkel, Bernd P.; Blechinger, Fritz; Lutz, Reinhold; Posselt, Winfried; Del Bello, Umberto; Meynart, Roland; Lobb, Daniel R.; Saint-Pe, Olivier

    1995-11-01

    Dasa (Daimler-Benz Aerospace) currently is in charge of an ESA contract for the PRISM feasibility study, including MATRA MS/France and SIRA/UK. The main PRISM mission objectives are to monitor selected target areas with emphasis on bio-chemical stress analyses which are the subject of changes such as vegetation, in particular deforestation; further areas include glaciers, land/water boundaries, and similar features. The Dasa study team makes use of a similar ESA instrument currently the subject of dedicated subunits technology developments, the HRIS (high resolution imaging spectrometer), also lead by Dasa. Its main features and technology developments are covered in a survey. PRISM is covering most of the HRIS features, i.e., it will have an imaging spectrometer segment for the visible/NIR and the SWIR spectrum (450-2350 nm) as HRIS, but implements four MIR and TIR channels to provide surface temperature data, represented by linear detector arrays (essentially the features of another currently pursued ESA development program designated HRTIR). In a first study phase it also included a novel feature, a wide-angle two-axis pointing system for along- and across-track pointing in order to yield multi-directional reflectance data of dedicated targets, which turned out to be the greatest design driver in the instrument, it was omitted in the later phases. The geometric sampling interval is defined to 50 m (design goal) at 50 km swath. PRISM is currently studied in a feasibility study in a competitive way by two teams, one being lead by Dasa. At the time of the Symposium both studies are completed. The results of the Dasa team are presented. Since PRISM covers most of the HRIS mission it is rather likely that in the case of a successful concept feasibility proof (performance and technology wise), it may later replace the HRIS instrument. It is anticipated that a major part of the technology developments currently performed for HRIS will be utilized -- with some

  7. Medical images of patients in voxel structures in high resolution for Monte Carlo simulation

    International Nuclear Information System (INIS)

    Boia, Leonardo S.; Menezes, Artur F.; Silva, Ademir X.

    2011-01-01

    This work aims to present a computational process of conversion of tomographic and MRI medical images from patients in voxel structures to an input file, which will be manipulated in Monte Carlo Simulation code for tumor's radiotherapic treatments. The problem's scenario inherent to the patient is simulated by such process, using the volume element (voxel) as a unit of computational tracing. The head's voxel structure geometry has voxels with volumetric dimensions around 1 mm 3 and a population of millions, which helps - in that way, for a realistic simulation and a decrease in image's digital process techniques for adjustments and equalizations. With such additional data from the code, a more critical analysis can be developed in order to determine the volume of the tumor, and the protection, beside the patients' medical images were borrowed by Clinicas Oncologicas Integradas (COI/RJ), joined to the previous performed planning. In order to execute this computational process, SAPDI computational system is used in a digital image process for optimization of data, conversion program Scan2MCNP, which manipulates, processes, and converts the medical images into voxel structures to input files and the graphic visualizer Moritz for the verification of image's geometry placing. (author)

  8. Development of a compact scintillator-based high-resolution Compton camera for molecular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, A., E-mail: daphne3h-aya@ruri.waseda.jp [Research Institute for Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku, Tokyo (Japan); Kataoka, J.; Koide, A.; Sueoka, K.; Iwamoto, Y.; Taya, T. [Research Institute for Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku, Tokyo (Japan); Ohsuka, S. [Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu, Shizuoka (Japan)

    2017-02-11

    The Compton camera, which shows gamma-ray distribution utilizing the kinematics of Compton scattering, is a promising detector capable of imaging across a wide range of energy. In this study, we aim to construct a small-animal molecular imaging system in a wide energy range by using the Compton camera. We developed a compact medical Compton camera based on a Ce-doped Gd{sub 3}Al{sub 2}Ga{sub 3}O{sub 12} (Ce:GAGG) scintillator and multi-pixel photon counter (MPPC). A basic performance confirmed that for 662 keV, the typical energy resolution was 7.4 % (FWHM) and the angular resolution was 4.5° (FWHM). We then used the medical Compton camera to conduct imaging experiments based on a 3-D imaging reconstruction algorithm using the multi-angle data acquisition method. The result confirmed that for a {sup 137}Cs point source at a distance of 4 cm, the image had a spatial resolution of 3.1 mm (FWHM). Furthermore, we succeeded in producing 3-D multi-color image of different simultaneous energy sources ({sup 22}Na [511 keV], {sup 137}Cs [662 keV], and {sup 54}Mn [834 keV]).

  9. Medical images of patients in voxel structures in high resolution for Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Boia, Leonardo S.; Menezes, Artur F.; Silva, Ademir X., E-mail: lboia@con.ufrj.b, E-mail: ademir@con.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear; Salmon Junior, Helio A. [Clinicas Oncologicas Integradas (COI), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    This work aims to present a computational process of conversion of tomographic and MRI medical images from patients in voxel structures to an input file, which will be manipulated in Monte Carlo Simulation code for tumor's radiotherapic treatments. The problem's scenario inherent to the patient is simulated by such process, using the volume element (voxel) as a unit of computational tracing. The head's voxel structure geometry has voxels with volumetric dimensions around 1 mm{sup 3} and a population of millions, which helps - in that way, for a realistic simulation and a decrease in image's digital process techniques for adjustments and equalizations. With such additional data from the code, a more critical analysis can be developed in order to determine the volume of the tumor, and the protection, beside the patients' medical images were borrowed by Clinicas Oncologicas Integradas (COI/RJ), joined to the previous performed planning. In order to execute this computational process, SAPDI computational system is used in a digital image process for optimization of data, conversion program Scan2MCNP, which manipulates, processes, and converts the medical images into voxel structures to input files and the graphic visualizer Moritz for the verification of image's geometry placing. (author)

  10. High-Resolution Magnetic Resonance Imaging Can Reliably Detect Orbital Tumor Recurrence after Enucleation in Children with Retinoblastoma.

    Science.gov (United States)

    Sirin, Selma; de Jong, Marcus C; de Graaf, Pim; Brisse, Hervé J; Galluzzi, Paolo; Maeder, Philippe; Bornfeld, Norbert; Biewald, Eva; Metz, Klaus A; Temming, Petra; Castelijns, Jonas A; Goericke, Sophia L

    2016-03-01

    Orbital tumor recurrence is a rare but serious complication in children with retinoblastoma, leading to a high risk of metastasis and death. Therefore, we assume that these recurrences have to be detected and treated as early as possible. Preliminary studies used magnetic resonance imaging (MRI) to evaluate postsurgical findings in the orbit. In this study, we assessed the diagnostic accuracy of high-resolution MRI to detect orbital tumor recurrence in children with retinoblastoma in a large study cohort. Consecutive retrospective study (2007-2013) assessing MRI findings after enucleation. A total of 103 MRI examinations of 55 orbits (50 children, 27 male/23 female, mean age 16.3±12.4 months) with a median time of 8 months (range, 0-93) after enucleation for retinoblastoma. High-resolution MRI using orbital surface coils was performed on 1.5 Tesla MRI systems to assess abnormal orbital findings. Five European experts in retinoblastoma imaging evaluated the MRI examinations regarding the presence of abnormal orbital gadolinium enhancement and judged them as "definitive tumor," "suspicious of tumor," "postsurgical condition/scar formation," or "without pathologic findings." The findings were correlated to histopathology (if available), MRI, and clinical follow-up. Abnormal orbital enhancement was a common finding after enucleation (100% in the first 3 months after enucleation, 64.3% >3 years after enucleation). All histopathologically confirmed tumor recurrences (3 of 55 orbits, 5.5%) were correctly judged as "definitive tumor" in MRI. Two orbits from 2 children rated as "suspicious of tumor" received intravenous chemotherapy without histopathologic confirmation; further follow-up (67 and 47 months) revealed no sign of tumor recurrence. In 90.2%, no tumor was suspected on MRI, which was clinically confirmed during follow-up (median follow-up after enucleation, 45 months; range, 8-126). High-resolution MRI with orbital surface coils may reliably distinguish between

  11. In vivo imaging enables high resolution preclinical trials on patients' leukemia cells growing in mice.

    Directory of Open Access Journals (Sweden)

    Nadia Terziyska

    Full Text Available Xenograft mouse models represent helpful tools for preclinical studies on human tumors. For modeling the complexity of the human disease, primary tumor cells are by far superior to established cell lines. As qualified exemplary model, patients' acute lymphoblastic leukemia cells reliably engraft in mice inducing orthotopic disseminated leukemia closely resembling the disease in men. Unfortunately, disease monitoring of acute lymphoblastic leukemia in mice is hampered by lack of a suitable readout parameter.Patients' acute lymphoblastic leukemia cells were lentivirally transduced to express the membrane-bound form of Gaussia luciferase. In vivo imaging was established in individual patients' leukemias and extensively validated.Bioluminescence in vivo imaging enabled reliable and continuous follow-up of individual mice. Light emission strictly correlated to post mortem quantification of leukemic burden and revealed a logarithmic, time and cell number dependent growth pattern. Imaging conveniently quantified frequencies of leukemia initiating cells in limiting dilution transplantation assays. Upon detecting a single leukemia cell within more than 10,000 bone marrow cells, imaging enabled monitoring minimal residual disease, time to tumor re-growth and relapse. Imaging quantified therapy effects precisely and with low variances, discriminating treatment failure from partial and complete responses.For the first time, we characterized in detail how in vivo imaging reforms preclinical studies on patient-derived tumors upon increasing monitoring resolution. In the future, in vivo imaging will enable performing precise preclinical studies on a broad range of highly demanding clinical challenges, such as treatment failure, resistance in leukemia initiating cells, minimal residual disease and relapse.

  12. Classification of high-resolution remote sensing images based on multi-scale superposition

    Science.gov (United States)

    Wang, Jinliang; Gao, Wenjie; Liu, Guangjie

    2017-07-01

    Landscape structures and process on different scale show different characteristics. In the study of specific target landmarks, the most appropriate scale for images can be attained by scale conversion, which improves the accuracy and efficiency of feature identification and classification. In this paper, the authors carried out experiments on multi-scale classification by taking the Shangri-la area in the north-western Yunnan province as the research area and the images from SPOT5 HRG and GF-1 Satellite as date sources. Firstly, the authors upscaled the two images by cubic convolution, and calculated the optimal scale for different objects on the earth shown in images by variation functions. Then the authors conducted multi-scale superposition classification on it by Maximum Likelyhood, and evaluated the classification accuracy. The results indicates that: (1) for most of the object on the earth, the optimal scale appears in the bigger scale instead of the original one. To be specific, water has the biggest optimal scale, i.e. around 25-30m; farmland, grassland, brushwood, roads, settlement places and woodland follows with 20-24m. The optimal scale for shades and flood land is basically as the same as the original one, i.e. 8m and 10m respectively. (2) Regarding the classification of the multi-scale superposed images, the overall accuracy of the ones from SPOT5 HRG and GF-1 Satellite is 12.84% and 14.76% higher than that of the original multi-spectral images, respectively, and Kappa coefficient is 0.1306 and 0.1419 higher, respectively. Hence, the multi-scale superposition classification which was applied in the research area can enhance the classification accuracy of remote sensing images .

  13. High Resolution/High Fidelity Seismic Imaging and Parameter Estimation for Geological Structure and Material Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Ru-Shan Wu, Xiao-Bi Xie, Thorne Lay

    2005-06-06

    In this project, we develop new theories and methods for multi-domain one-way wave-equation based propagators, and apply these techniques to seismic modeling, seismic imaging, seismic illumination and model parameter estimation in 3D complex environments. The major progress of this project includes: (1) The development of the dual-domain wave propagators. We continue to improve the one-way wave-equation based propagators. Our target is making propagators capable of handling more realistic velocity models. A wide-angle propagator for transversely isotropic media with vertically symmetric axis (VTI) has been developed for P-wave modeling and imaging. The resulting propagator is accurate for large velocity perturbations and wide propagation angles. The thin-slab propagator for one-way elastic-wave propagation is further improved. With the introduction of complex velocities, the quality factors Qp and Qs have been incorporated into the thin-slab propagator. The resulting viscoelastic thin-slab propagator can handle elastic-wave propagation in models with intrinsic attenuations. We apply this method to complex models for AVO modeling, random media characterization and frequency-dependent reflectivity simulation. (2) Exploring the Information in the Local Angle Domain. Traditionally, the local angle information can only be extracted using the ray-based method. We develop a wave-equation based technique to process the local angle domain information. The approach can avoid the singularity problem usually linked to the high-frequency asymptotic method. We successfully apply this technique to seismic illumination and the resulting method provides a practical tool for three-dimensional full-volume illumination analysis in complex structures. The directional illumination also provides information for angle-domain imaging corrections. (3) Elastic-Wave Imaging. We develop a multicomponent elastic migration method. The application of the multicomponent one-way elastic propagator

  14. Designing sparse sensing matrix for compressive sensing to reconstruct high resolution medical images

    Directory of Open Access Journals (Sweden)

    Vibha Tiwari

    2015-12-01

    Full Text Available Compressive sensing theory enables faithful reconstruction of signals, sparse in domain $ \\Psi $, at sampling rate lesser than Nyquist criterion, while using sampling or sensing matrix $ \\Phi $ which satisfies restricted isometric property. The role played by sensing matrix $ \\Phi $ and sparsity matrix $ \\Psi $ is vital in faithful reconstruction. If the sensing matrix is dense then it takes large storage space and leads to high computational cost. In this paper, effort is made to design sparse sensing matrix with least incurred computational cost while maintaining quality of reconstructed image. The design approach followed is based on sparse block circulant matrix (SBCM with few modifications. The other used sparse sensing matrix consists of 15 ones in each column. The medical images used are acquired from US, MRI and CT modalities. The image quality measurement parameters are used to compare the performance of reconstructed medical images using various sensing matrices. It is observed that, since Gram matrix of dictionary matrix ($ \\Phi \\Psi \\mathrm{} $ is closed to identity matrix in case of proposed modified SBCM, therefore, it helps to reconstruct the medical images of very good quality.

  15. Designing A New CAD System for Pulmonary Nodule Detection in High Resolution Computed Tomography (HRCT Images

    Directory of Open Access Journals (Sweden)

    M Bakhshayesh Karam

    2012-07-01

    Full Text Available Background: Lung diseases and lung cancer are among the most dangerous diseases with high mortality in both men and women. Lung nodules are abnormal pulmonary masses and are among major lung symptoms. A Computer Aided Diagnosis (CAD system may play an important role in accurate and early detection of lung nodules. This article presents a new CAD system for lung nodule detection from chest computed tomography (CT images.Methods: Twenty-five adult patients with lung nodules in their CT scan images presented to the National Research Institute of Tuberculosis and Lung Disease, Masih Daneshvari Hospital, Tehran, Iran in 2011-2012 were enrolled in the study. The patients were randomly assigned into two experimental (9 female, 6 male, mean age 43±5.63 yrs and control (6 female, 4 male, mean age 39±4.91 yrs groups. A fully-automatic method was developed for detecting lung nodules by employing medical image processing and analysis and statistical pattern recognition algorithms.esults: Using segmentation methods, the lung parenchyma was extracted from 2-D CT images. Then, candidate regions were labeled in pseudo-color images. In the next step, some features of lung nodules were extracted. Finally, an artificial feed forward neural network was used for classification of nodules.Conclusion: Considering the complexity and different shapes of lung nodules and large number of CT images to evaluate, finding lung nodules are difficult and time consuming for physicians and include human error. Experimental results showed the accuracy of the proposed method to be appropriate (P<0.05 for lung nodule detection.

  16. Three very high resolution optical images for land use mapping of a suburban catchment: input to distributed hydrological models

    Science.gov (United States)

    Jacqueminet, Christine; Kermadi, Saïda; Michel, Kristell; Jankowfsky, Sonja; Braud, Isabelle; Branger, Flora; Beal, David; Gagnage, Matthieu

    2010-05-01

    Keywords : land cover mapping, very high resolution, remote sensing processing techniques, object oriented approach, distributed hydrological model, peri-urban area Urbanization and other modifications of land use affect the hydrological cycle of suburban catchments. In order to quantify these impacts, the AVuPUR project (Assessing the Vulnerability of Peri-Urban Rivers) is currently developing a distributed hydrological model that includes anthropogenic features. The case study is the Yzeron catchment (150 km²), located close to Lyon city, France. This catchment experiences a growing of urbanization and a modification of traditional land use since the middle of the 20th century, resulting in an increase of flooding, water pollution and river banks erosion. This contribution discusses the potentials of automated data processing techniques on three different VHR images, in order to produce appropriate and detailed land cover data for the models. Of particular interest is the identification of impermeable surfaces (buildings, roads, and parking places) and permeable surfaces (forest areas, agricultural fields, gardens, trees…) within the catchment, because their infiltration capacity and their impact on runoff generation are different. Three aerial and spatial images were acquired: (1) BD Ortho IGN aerial images, 0.50 m resolution, visible bands, may 5th 2008; (2) QuickBird satellite image, 2.44 m resolution, visible and near-infrared bands, august 29th 2008; (3) Spot satellite image, 2.50 m resolution, visible and near-infrared bands, September 22nd 2008. From these images, we developed three image processing methods: (1) a pixel-based method associated to a segmentation using Matlab®, (2) a pixel-based method using ENVI®, (3) an object-based classification using Definiens®. We extracted six land cover types from the BD Ortho IGN (visible bands) and height classes from the satellite images (visible and near infrared bands). The three classified images are

  17. High-resolution 3D-GRE imaging of the abdomen using controlled aliasing acceleration technique - a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    AlObaidy, Mamdoh; Ramalho, Miguel; Busireddy, Kiran K.R.; Liu, Baodong; Burke, Lauren M.; Altun, Ersan; Semelka, Richard C. [University of North Carolina at Chapel Hill, Department of Radiology, Chapel Hill, NC (United States); Dale, Brian M. [Siemens Medical Solutions, MR Research and Development, Morrisville, NC (United States)

    2015-12-15

    To assess the feasibility of high-resolution 3D-gradient-recalled echo (GRE) fat-suppressed T1-weighted images using controlled aliasing acceleration technique (CAIPIRINHA-VIBE), and compare image quality and lesion detection to standard-resolution 3D-GRE images using conventional acceleration technique (GRAPPA-VIBE). Eighty-four patients (41 males, 43 females; age range: 14-90 years, 58.8 ± 15.6 years) underwent abdominal MRI at 1.5 T with CAIPIRINHA-VIBE [spatial resolution, 0.76 ± 0.04 mm] and GRAPPA-VIBE [spatial resolution, 1.17 ± 0.14 mm]. Two readers independently reviewed image quality, presence of artefacts, lesion conspicuity, and lesion detection. Kappa statistic was used to assess interobserver agreement. Wilcoxon signed-rank test was used for image qualitative pairwise comparisons. Logistic regression with post-hoc testing was used to evaluate statistical significance of lesions evaluation. Interobserver agreement ranged between 0.45-0.93. Pre-contrast CAIPIRINHA-VIBE showed significantly (p < 0.001) sharper images and lesion conspicuity with decreased residual aliasing, but more noise enhancement and inferior image quality. Post-contrast CAIPIRINHA-VIBE showed significantly (p < 0.001) sharper images and higher lesion conspicuity, with less respiratory motion and residual aliasing artefacts. Inferior fat-suppression was noticeable on CAIPIRINHA-VIBE sequences (p < 0.001). High in-plane resolution abdominal 3D-GRE fat-suppressed T1-weighted imaging using controlled-aliasing acceleration technique is feasible and yields sharper images compared to standard-resolution images using standard acceleration, with higher post-contrast image quality and trend for improved hepatic lesions detection. (orig.)

  18. High-resolution three-dimensional compositional imaging by double-pulse laser-induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Schiavo, C.; Grifoni, E.; Legnaioli, S.; Lorenzetti, G.; Poggialini, F.; Pagnotta, S.; Palleschi, V.; Menichetti, L.

    2016-01-01

    In this paper we present a new instrument specifically realized for high-resolution three-dimensional compositional analysis and mapping of materials. The instrument is based on the coupling of a Double-Pulse Laser-Induced Breakdown Spectroscopy (LIBS) instrument with an optical microscope. The compositional mapping of the samples is obtained by scanning the laser beam across the surface of the sample, while the in depth analysis is performed by sending multiple laser pulses on the same point. Depths of analysis of several tens of microns can be obtained. The instrument presented has definite advantages with respect to Laser Ablation-ICP Mass Spectrometry in many applications related to material analysis, biomedicine and environmental diagnostics. An application to the diagnostics of industrial ceramics is presented, demonstrating the feasibility of Double-Pulse LIBS Imaging and its advantages with respect to conventional single-pulse LIBS imaging.

  19. Analysis of Properties of Reflectance Reference Targets for Permanent Radiometric Test Sites of High Resolution Airborne Imaging Systems

    Directory of Open Access Journals (Sweden)

    Eero Ahokas

    2010-08-01

    Full Text Available Reliable and optimal exploitation of rapidly developing airborne imaging methods requires geometric and radiometric quality assurance of production systems in operational conditions. Permanent test sites are the most promising approach for cost-efficient performance assessment. Optimal construction of permanent radiometric test sites for high resolution airborne imaging systems is an unresolved issue. The objective of this study was to assess the performance of commercially available gravels and painted and unpainted concrete targets for permanent, open-air radiometric test sites under sub-optimal climate conditions in Southern Finland. The reflectance spectrum and reflectance anisotropy and their stability were characterized during the summer of 2009. The management of reflectance anisotropy and stability were shown to be the key issues for better than 5% reflectance accuracy.

  20. Detecting and locating light atoms from high-resolution STEM images: The quest for a single optimal design.

    Science.gov (United States)

    Gonnissen, J; De Backer, A; den Dekker, A J; Sijbers, J; Van Aert, S

    2016-11-01

    In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of light atoms from HR STEM images. To determine the optimal experiment design for locating light atoms, use is made of the so-called Cramér-Rao Lower Bound (CRLB). It is investigated if a single optimal design can be found for both the detection and location problem of light atoms. Furthermore, the incoming electron dose is optimised for both research goals and it is shown that picometre range precision is feasible for the estimation of the atom positions when using an appropriate incoming electron dose under the optimal detector settings to detect light atoms. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography

    Science.gov (United States)

    Olivier, Scot S.; Werner, John S.; Zawadzki, Robert J.; Laut, Sophie P.; Jones, Steven M.

    2010-09-07

    This invention permits retinal images to be acquired at high speed and with unprecedented resolution in three dimensions (4.times.4.times.6 .mu.m). The instrument achieves high lateral resolution by using adaptive optics to correct optical aberrations of the human eye in real time. High axial resolution and high speed are made possible by the use of Fourier-domain optical coherence tomography. Using this system, we have demonstrated the ability to image microscopic blood vessels and the cone photoreceptor mosaic.

  2. Information Extraction of High-Resolution Remotely Sensed Image Based on Multiresolution Segmentation

    Directory of Open Access Journals (Sweden)

    Peng Shao

    2014-08-01

    Full Text Available The principle of multiresolution segmentation was represented in detail in this study, and the canny algorithm was applied for edge-detection of a remotely sensed image based on this principle. The target image was divided into regions based on object-oriented multiresolution segmentation and edge-detection. Furthermore, object hierarchy was created, and a series of features (water bodies, vegetation, roads, residential areas, bare land and other information were extracted by the spectral and geometrical features. The results indicate that the edge-detection has a positive effect on multiresolution segmentation, and overall accuracy of information extraction reaches to 94.6% by the confusion matrix.

  3. Advances in high-resolution imaging and computational unfolding of the human hippocampus.

    Science.gov (United States)

    Ekstrom, Arne D; Bazih, Adam J; Suthana, Nanthia A; Al-Hakim, Ramsey; Ogura, Kenji; Zeineh, Michael; Burggren, Alison C; Bookheimer, Susan Y

    2009-08-01

    The hippocampus is often a difficult structure to visualize with magnetic resonance imaging (MRI) and functional MRI (fMRI) due to its convoluted nature and susceptibility to signal dropout. Improving our ability to pinpoint changes in neural activity using fMRI in this structure remains an important challenge. Current fMRI/MRI methods typically do not permit visualization of the hippocampus and surrounding cortex at a resolution less than 1 mm. We present here improvements to our previous methods for obtaining structural MR images of the hippocampus, which provided an in-plane resolution of 0.4 mm(2) mm and two-dimensional "flat" maps of the hippocampus with an interpolated isotropic resolution of 0.4 mm(3) (Engel, S.A., Glover, G.H., and Wandell, B.A., (1997). Retinotopic organization in human visual cortex and the spatial precision of functional MRI. Cereb. Cortex 7, 181-192.; Zeineh, M.M., Engel, S.A., and Bookheimer, S.Y., (2000). Application of cortical unfolding techniques to functional MRI of the human hippocampal region. NeuroImage 11, 668-683.). We present changes to existing structural imaging sequences that now augment the resolution of previous scans, permitting visualization of the anterior portion of CA1, parts of the dentate gyrus, and CA23. These imaging improvements are of relevance generally to the field of imaging because they permit higher overall resolution imaging of the hippocampus than previously possible (at 3 T). We also introduce a novel application of a computational interpolation method that improves our ability to capture the convoluted three-dimensional shape of the hippocampus. Furthermore, we have developed a quantitative method for obtaining group activation patterns based on producing averaged flat maps using vector field warping techniques, allowing localization of activations to specific hippocampal subregions across groups of subjects. Together, these methods provide a means to improve imaging of neural activity in the human

  4. The Megapixel EBCCD a high-resolution imaging tube sensitive to single photons

    CERN Document Server

    Buontempo, S; Dalinenko, I N; Ereditato, A; Ekimov, A V; Fabre, Jean-Paul; Fedorov, V Yu; Frenkel, A; Galeazzi, F; Garufi, F; Golovkin, S V; Govorun, V N; Kalashnikova, N N; Kosov, V G; Kozarenko, E N; Kreslo, I E; Lasovsky, L Y; Liberti, B; Malyarov, A V; Martellotti, G; Medvedkov, A M; Penso, G; Vishnevski, G I; Wolff, T; Zhuk, A

    1998-01-01

    A hybrid image-intensifier tube, suitable for extremely low-light imaging, has been tested. This device is based on an Electron-Bombarded CCD chip (EBCCD) with $1024 \\times 1024$ sensitive pixe ls. The tube, which has a photocathode diameter of 40 mm, is gateable and zoomable, with an image magnification varying from 0.62 to 1.3. The high gain (about 4000 collected electrons per photo electron at the operational voltage of 15 kV) and the relatively low noise (180 electrons per pixel at 10 MHz pixel-readout frequency), allows single-photoelectron signals to be separated from n oise with a signal-to-noise ratio greater than 10. By applying an appropriate threshold on the signal amplitude, the background can almost be eliminated, with a loss of few percent in single-ph otoelectron counting. High inner gain, low noise, single-photoelectron sensitivity, and high spatial resolution make the EBCCD imaging tube a unique device, attractive for many applications in h igh-energy physics, astrophysics, biomedical diagnos...

  5. Imaging of native transcription factors and histone phosphorylation at high resolution in live cells.

    Science.gov (United States)

    Conic, Sascha; Desplancq, Dominique; Ferrand, Alexia; Fischer, Veronique; Heyer, Vincent; Reina San Martin, Bernardo; Pontabry, Julien; Oulad-Abdelghani, Mustapha; Babu N, Kishore; Wright, Graham D; Molina, Nacho; Weiss, Etienne; Tora, László

    2018-04-02

    Fluorescent labeling of endogenous proteins for live-cell imaging without exogenous expression of tagged proteins or genetic manipulations has not been routinely possible. We describe a simple versatile antibody-based imaging approach (VANIMA) for the precise localization and tracking of endogenous nuclear factors. Our protocol can be implemented in every laboratory allowing the efficient and nonharmful delivery of organic dye-conjugated antibodies, or antibody fragments, into different metazoan cell types. Live-cell imaging permits following the labeled probes bound to their endogenous targets. By using conventional and super-resolution imaging we show dynamic changes in the distribution of several nuclear transcription factors (i.e., RNA polymerase II or TAF10), and specific phosphorylated histones (γH2AX), upon distinct biological stimuli at the nanometer scale. Hence, considering the large panel of available antibodies and the simplicity of their implementation, VANIMA can be used to uncover novel biological information based on the dynamic behavior of transcription factors or posttranslational modifications in the nucleus of single live cells. © 2018 Conic et al.

  6. Designing a new CAD system for pulmonary nodule detection in High Resolution Computed Tomography (HRCT images

    Directory of Open Access Journals (Sweden)

    Parsa Hosseini M

    2012-07-01

    Conclusion: Considering the complexity and different shapes of lung nodules and large number of CT images to evaluate, finding lung nodules are difficult and time consuming for physicians and include human error. Experimental results showed the accuracy of the proposed method to be appropriate (P<0.05 for lung nodule detection.

  7. A directly converting high-resolution intra-oral X-ray imaging sensor

    CERN Document Server

    Spartiotis, K; Schulman, T; Puhakka, K; Muukkonen, K

    2003-01-01

    A digital intra-oral X-ray imaging sensor with an active area of 3.6x2.9 cm sup 2 and consisting of six charge-integrating CMOS signal readout circuits bump bonded to one high-resistivity s