Sample records for image cloud patterns

  1. Exploration Activity: Global Cloud Patterns

    NSDL National Science Digital Library

    Dave Dempsey

    2005-03-10

    In this activity, students characterize some global patterns of deep, cold-topped clouds visible on global infrared satellite images. They will apply these characterizations to answer questions about local and global patterns of precipitation. The questions concern what clouds are and how they form, atmospheric cooling, rising air, precipitation, and the use of remote satellite imagery to see precipitation-producing clouds and storms. They will also create animated global infrared satellite images and answer some questions concerning them.

  2. An Application of Fractal Box Dimension to the Recognition of Mesoscale Cloud Patterns in Infrared Satellite Images

    Microsoft Academic Search

    Leila M. V. Carvalho; Maria A. F. Silva Dias

    1998-01-01

    Mesoscale cloud patterns are analyzed through the application of fractal box dimensions. Verification of fractal properties in satellite infrared images is carried out by computing box dimensions with two different methods and by computing the fraction of cloudy pixels for two sets of images: 174 are considered the ''control series,'' and 178 (for verification) are considered the ''test series.'' The

  3. Detailed Cloud Patterns in Martian Northern Hemisphere

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Cold and cloudy mornings; cool, hazy afternoons. High winds aloft and weather fronts moving slowly to the east. It is winter in the Martian northern hemisphere. One of the many reasons to study Mars is that, at times, its weather is very 'Earth-like.' At this time of the Martian year, clouds are abundant, especially in the morning and especially in the high northern latitudes. Clouds and fogs are also observed in low-lying areas farther to the south, in some lowlands they are as far south as the equator.

    The above color composite images, obtained by Mars Global Surveyor's camera on June 4, 1998, illustrate this Martian 'weather report.' Most of the thick, white clouds seen here occur north of latitude 35oN (roughly equivalent to Albuquerque NM, Memphis TN, and Charlotte, NC). Fog (seen as bright orange because it is lighter than the ground but some of the ground is still visible) occupies the lowest portions of the Kasei Valles outflow channel around 30oN and at 25oN.

    Several different types of cloud features are seen. The repetitious, wash-board pattern of parallel lines are 'gravity wave clouds'. These commonly form, in the lee--downwind side-- of topographic features such as mountain ranges (on Earth) or crater rims (on Mars), under very specific atmospheric conditions (low temperatures, high humidity, and high wind speeds). In this area, the wave clouds are lower in the atmosphere than some of the other clouds. These other clouds show attributes reflecting more the regional weather pattern, occasionally showing the characteristic 'slash' shape (southwest to northeast) of a weather front. These clouds probably contain mostly crystals of water ice but, depending on the temperature at high altitude (and more likely closer to the pole), some could also contain frozen carbon dioxide ('dry ice').

    MOC images 34501 (the red wide angle image) and 34502 (the blue wide angle image) were obtained on Mars Global Surveyor's 345th orbit about the planet. The pictures were taken around 5: 34 p.m. PDT on June 4, 1998. Winter in the northern hemisphere began in mid-February, 1998, and continues to mid-July, 1998.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  4. Cloud Statistics Measured With the Infrared Cloud Imager (ICI)

    Microsoft Academic Search

    Brentha Thurairajah; Joseph A. Shaw

    2005-01-01

    The Infrared Cloud Imager (ICI) is a ground-based thermal infrared imaging system that measures spatial cloud statistics with a 320$,times,$240-pixel uncooled microbolometer detector array. Clouds are identified from the residual radiance that remains after water vapor emission is removed from radiometrically calibrated sky images (the water vapor correction relies on measurements of precipitable water vapor and near-surface air temperature). Cloud

  5. The Research of Satellite Cloud Image Recognition Base on Variational Method and Texture Feature Analysis

    Microsoft Academic Search

    Wei Shangguan; Yanling Hao; Zhizhong Lu; Peng Wu

    2007-01-01

    Recently, the development of satellite cloud image processing technology has become very quick; the research aspects concentrate on judge the cloud type and classify the cloud mainly. These image processing methods relate to the subject category like image processing and pattern recognition etc; it has become one of the fields of most quickly development in the research of satellite image

  6. Identifying Cloud computing usage patterns

    Microsoft Academic Search

    Dana Petcu

    2010-01-01

    The current end-users who are developing Cloud-based applications are struggling with multiple solutions for application programming interfaces (APIs) coming from different providers. This fact is partially a consequence of the focus of these APIs on the service provider expectations not on the end-user requirements. In the design of a generic API for Cloud application development, the first step should be

  7. Cloud Ozone Dust Imager (CODI)

    Microsoft Academic Search

    R. Todd Clancy; Paul Dusenbery; Michael Wolff; Phil James; Mark Allen; Jay Goguen; Ralph Kahn; Rany Gladstone; Jim Murphy

    1995-01-01

    The Cloud Ozone Dust Imager (CODI) is proposed to investigate the current climatic balance of the Mars atmosphere, with particular emphasis on the important but poorly understood roles which dust and water ice aerosols play in this balance. The large atmospheric heating (20-50 K) resulting from global dust storms around Mars perihelion is well recognized. However, groundbased observations of Mars

  8. Cloud Ozone Dust Imager (CODI)

    NASA Astrophysics Data System (ADS)

    Clancy, R. Todd; Dusenbery, Paul; Wolff, Michael; James, Phil; Allen, Mark; Goguen, Jay; Kahn, Ralph; Gladstone, Rany; Murphy, Jim

    1995-01-01

    The Cloud Ozone Dust Imager (CODI) is proposed to investigate the current climatic balance of the Mars atmosphere, with particular emphasis on the important but poorly understood roles which dust and water ice aerosols play in this balance. The large atmospheric heating (20-50 K) resulting from global dust storms around Mars perihelion is well recognized. However, groundbased observations of Mars atmospheric temperatures, water vapor, and clouds since the Viking missions have identified a much colder, cloudier atmosphere around Mars aphelion that may prove as important as global dust storms in determining the interannual and long-term behavior of the Mars climate. The key climate issues CODI is designed to investigate are: 1) the degree to which non-linear interactions between atmospheric dust heating, water vapor saturation, and cloud nucleation influence the seasonal and interannual variability of the Mars atmosphere, and 2) whether the strong orbital forcing of atmospheric dust loading, temperatures and water vapor saturation determines the long-term balance of Mars water, as reflected in the north-south hemispheric asymmetries of atmospheric water vapor and polar water ice abundances. The CODI experiment will measure the daily, seasonal and (potentially) interannual variability of atmospheric dust and cloud opacities, and the key physical properties of these aerosols which determine their role in the climate cycles of Mars. CODI is a small (1.2 kg), fixed pointing camera, in which four wide-angle (+/- 70 deg) lenses illuminate fixed filters and CCD arrays. Simultaneous sky/surface imaging of Mars is obtained at an angular resolution of 0.28 deg/pixel for wavelengths of 255, 336, 502, and 673 nm (similar to Hubble Space Telescope filters). These wavelengths serve to measure atmospheric ozone (255 and 336 nm), discriminate ice and dust aerosols (336 and 673 nm), and construct color images (336, 502, and 673 nm). The CODI images are detected on four 512 x 512 pixel arrays, as partitioned on two 1024 x 1024 CCD's operated in frame transfer mode. The center of the CODI field-of-view is canted 40 deg from the zenith direction to obtain sky brightness measurements and a 20 deg surface field-of-view. Daily image observations will be conducted when the Sun is greater than or equal to 5 deg outside the edge of the CODI field-of-view, and twilight and nighttime imaging will obtained on a weekly basis. The 673 nm channel includes a polarizer wheel to obtain sky/surface polarimetry. A dust cover protects the entire lens assemblies of all four CODI channels. This opaque dust cover, which is normally opened for CODI imaging, includes a small fixed mirror and transparent window positioned above the 673 nm lens, to redirect the 673 nm field-of-view to the surface for descent imaging. Fixed pointing, internal data buffering, low operating power (2-4 W for less than or equal to 30 seconds), selective data transmission, and simple operational characteristics of the CODI experiment place minimum resource and operational demands on the Mars Surveyor 1998 lander. The CODI science goals are optimized for, but not restricted to, a low-latitude landing site (20 deg S-30 deg N). The primary CODI measurement objectives are the opacities, wave forms, particle properties (size, shape, and alignment), and heights of clouds; the opacities, particle properties, and vertical distribution of dust; and the opacity and vertical distribution of ozone. The variability of cloud, ozone, and dust opacities will be determined on diurnal, daily, and seasonal timescales. Wind velocities will be determined from cloud motions and wave characteristics; and the temporal variability of atmospheric water vapor, with limited altitude information, will be inferred from the CODI ozone observations. Secondary measurement objectives include limited descent imaging capability, surface uv-visible photometry and polarimetry, photochemistry, and meteorite infall rates.

  9. SYSTEMATIC STUDY OF COLOR SPACES AND COMPONENTS FOR THE SEGMENTATION OF SKY/CLOUD IMAGES

    E-print Network

    Winkler, Stefan

    SYSTEMATIC STUDY OF COLOR SPACES AND COMPONENTS FOR THE SEGMENTATION OF SKY/CLOUD IMAGES) is a cost-effective means to understanding cloud cover and weather patterns. The accurate segmentation/cloud images. Using mainly principal component analysis (PCA) and fuzzy clustering for evaluation, we identify

  10. Biomedical image analysis and processing in clouds

    NASA Astrophysics Data System (ADS)

    Bednarz, Tomasz; Szul, Piotr; Arzhaeva, Yulia; Wang, Dadong; Burdett, Neil; Khassapov, Alex; Chen, Shiping; Vallotton, Pascal; Lagerstrom, Ryan; Gureyev, Tim; Taylor, John

    2013-10-01

    Cloud-based Image Analysis and Processing Toolbox project runs on the Australian National eResearch Collaboration Tools and Resources (NeCTAR) cloud infrastructure and allows access to biomedical image processing and analysis services to researchers via remotely accessible user interfaces. By providing user-friendly access to cloud computing resources and new workflow-based interfaces, our solution enables researchers to carry out various challenging image analysis and reconstruction tasks. Several case studies will be presented during the conference.

  11. Image processing for weather satellite cloud segmentation

    Microsoft Academic Search

    I. J. H. Leung; J. E. Jordan

    1995-01-01

    Image segmentation of weather satellite imagery is an important first step in an automated weather forecasting system. Accurate cloud extraction is also important in the determination of solar radiative transfer in atmospheric research, where satellite observations are used as inputs to global climate models to predict climatic change. Most of the current cloud extraction algorithms tend to be quite complicated

  12. Analysis and synthesis of cloud pattern for radiation field studies

    SciTech Connect

    Beyer, H.G.; Hammer, A.; Luther, J.; Poplawska, J.; Stolzenburg, K.; Wieting, P. (Car von Ossietzky Universitaet Oldenburg (Germany))

    1994-05-01

    A method for the analysis of small scale, short term characteristics of radiations fields under intermediate sky conditions (clouds of cumulus type) is described. It is based on the extraction of cloud field structures from sky photographs. The cloud structures are described as fractal objects. Based on this representation a procedure for the generation of synthetic cloud pattern and related radiation fields is given. Statistical characteristics of synthetic irradiance data sets are compared with empirical data from an array of ground sensors.

  13. Usage Patterns to Provision for Scientific Experimentation in Clouds

    Microsoft Academic Search

    Eran Chinthaka Withana; Beth Plale

    2010-01-01

    Driven by the need to provision resources on demand, scientists are turning to commercial and research test-bed Cloud computing resources to run their scientific experiments. Job scheduling on cloud computing resources, unlike earlier platforms, is a balance between throughput and cost of executions. Within this context, we posit that usage patterns can improve the job execution, because these patterns allow

  14. Male pattern baldness (image)

    MedlinePLUS

    Male pattern baldness is a sex-linked characteristic that is passed from mother to child. A man can more accurately predict his chances of developing male pattern baldness by observing his mother's father than by looking ...

  15. Image Mining: Detecting Deforestation Patterns

    E-print Network

    Camara, Gilberto

    54 Chapter IV Image Mining: Detecting Deforestation Patterns Through Satellites Marcelino Pereira to analyze satellite images and extract knowledge from this kind of data. The Amazonia deforestation problem of change on deforested areas of Amazonia. The purpose of the authors is to present relevant technologies

  16. UV image processing to detect diffuse clouds

    NASA Astrophysics Data System (ADS)

    Armengot, M.; Gómez de Castro, A. I.; López-Santiago, J.; Sánchez-Doreste, N.

    2015-05-01

    The presence of diffuse clouds along the Galaxy is under consideration as far as they are related to stellar formation and their physical properties are not well understood. The signal received from most of these structures in the UV images is minimal compared to the point sources. The presence of noise in these images makes hard the analysis because the Signal-to-Noise ratio is proportionally much higher in these areas. However, the digital processing of the images shows that it is possible to enhance and target these clouds. Typically, this kind of treatment is done on purpose for specific research areas and the Astrophysicist's work depends on the computer tools and its possibilities for enhancing a particular area based on a prior knowledge. Automating this step is the goal of our work to make easier the study of these structures in UV images. In particular we have used the GALEX survey images in the aim of learning to automatically detect such clouds and be able of unsupervised detection and graphic enhancement to log them. Our experiments show the existence of some evidences in the UV images that allow the systematic computing and open the chance to generalize the algorithm to find these structures in universe areas where they have not been recorded yet.

  17. First image of clouds over Mars

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is the first image ever taken from the surface of Mars of an overcast sky. Featured are stratus clouds coming from the northeast at about 15 miles per hour (6.7 meters/second) at an approximate height of ten miles (16 kilometers) above the surface. The 'you are here' notation marks where Earth was situated in the sky at the time the image was taken. Scientists had hoped to see Earth in this image, but the cloudy conditions prevented a clear viewing. Similar images will be taken in the future with the hope of capturing a view of Earth. From Mars, Earth would appear as a tiny blue dot as a star would appear to an Earthbound observer. Pathfinder's imaging system will not be able to resolve Earth's moon. The clouds consist of water ice condensed on reddish dust particles suspended in the atmosphere. Clouds on Mars are sometimes localized and can sometimes cover entire regions, but have not yet been observed to cover the entire planet. The image was taken about an hour and forty minutes before sunrise by the Imager for Mars Pathfinder (IMP) on Sol 16 at about ten degrees up from the eastern Martian horizon.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages and Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  18. Analysis of Polar Clouds from Satellite Imagery Using Pattern Recognition and a Statistical Cloud Analysis Scheme.

    NASA Astrophysics Data System (ADS)

    Ebert, Elizabeth E.

    1989-05-01

    The analysis of cloud cover in the polar regions from satellite data is more difficult than at other latitudes because the visible and thermal contrasts between the cloud cover and the underlying surface are frequently quite small. Pattern recognition has proven to be a useful tool in detecting and identifying several cloud types over snow and ice. Here a pattern recognition algorithm in combined with a hybrid histogram-spatial coherence (HHSC) scheme to derive cloud classification and fractional coverage, surface and cloud visible albedos and infrared brightness temperatures from multispectral AVHRR satellite imagery. The accuracy of the cloud fraction estimates were between 0.05 and 0.26, based on the mean absolute difference between the automated and manual nephanalyses of nearly 1000 training samples. The HHSC demonstrated greater accuracy at estimating cloud friction than three different threshold. methods. An important result is that the prior classification of a sample may significantly improve the accuracy of the analysis of cloud fraction, albedos and brightness temperatures over that of an unclassified sample.The algorithm is demonstrated for a set of AVHRR imagery from the summertime Arctic. The automated classification and analysis are in good agreement with manual interpretation of the satellite imagery and with surface observations.

  19. Cloud-Screening Algorithm for ENVISAT\\/MERIS Multispectral Images

    Microsoft Academic Search

    Luis Gómez-Chovagomez-Chova; Gustavo Camps-Valls; J. Calpe; Luis Guanter; José Moreno

    2007-01-01

    This paper presents a methodology for cloud screen- ing of multispectral images acquired with the Medium Resolution Imaging Spectrometer (MERIS) instrument on-board the Envi- ronmental Satellite (ENVISAT). The method yields both a discrete cloud mask and a cloud-abundance product from MERIS level-1b data on a per-pixel basis. The cloud-screening method relies on the extraction of meaningful physical features (e.g., brightness

  20. A cloud-based medical image repository

    NASA Astrophysics Data System (ADS)

    Maeder, Anthony J.; Planitz, Birgit M.; El Rifai, Diaa

    2012-02-01

    Many widely used digital medical image collections have been established but these are generally used as raw data sources without related image analysis toolsets. Providing associated functionality to allow specific types of operations to be performed on these images has proved beneficial in some cases (e.g. brain image registration and atlases). However, toolset development to provide generic image analysis functions on medical images has tended to be ad hoc, with Open Source options proliferating (e.g. ITK). Our Automated Medical Image Collection Annotation (AMICA) system is both an image repository, to which the research community can contribute image datasets, and a search/retrieval system that uses automated image annotation. AMICA was designed for the Windows Azure platform to leverage the flexibility and scalability of the cloud. It is intended that AMICA will expand beyond its initial pilot implementation (for brain CT, MR images) to accommodate a wide range of modalities and anatomical regions. This initiative aims to contribute to advances in clinical research by permitting a broader use and reuse of medical image data than is currently attainable. For example, cohort studies for cases with particular physiological or phenotypical profiles will be able to source and include enough cases to provide high statistical power, allowing more individualised risk factors to be assessed and thus allowing screening and staging processes to be optimised. Also, education, training and credentialing of clinicians in image interpretation, will be more effective because it will be possible to select instances of images with specific visual aspects, or correspond to types of cases where reading performance improvement is desirable.

  1. Void and cloud patterns in a dusty plasma

    Microsoft Academic Search

    Feng Huang; Maofu Ye; Long Wang

    2004-01-01

    Voids and complex cloud patterns have been observed in a radio frequency (rf) discharge dusty plasma system. The structures\\u000a and behaviors of these patterns were investigated in two- and three-dimensions by shifting an illumination laser sheet beam\\u000a up and down. Two-dimensional (2D) circular voids, thin ring voids, and their coexistent voids were observed at the early stage\\u000a of particle growth.

  2. Imaging the debris cloud around Sakurai's object

    NASA Astrophysics Data System (ADS)

    Hinkle, Kenneth; Joyce, Richard

    2013-02-01

    Stellar evolution models predict a common but brief post-AGB episode of helium shell burning as the remnants of low mass stars enter the white dwarf sequence. Over the last century two nearly identical final flash events have been observed. The most recent and by far the best studied was of Sakurai's object=V4334 Sgr. Sakurai's object returned to AGB luminosity in 1995 and was obscured in a dust cloud of its own making by 1999. Using NIRI plus Altair we tentatively imaged the ejecta in 2010. We propose to confirm this detection. Images of the ejecta reveal the mass loss geometry and allow direct measurement of the nebular expansion. Observations of other final flash objects strongly disagree with standard predictions. Imaging the mass loss geometry and setting a distance to Sakurai from the expansion of the nebula will provide significant constraints on theory.

  3. Clouds

    NSDL National Science Digital Library

    First, the Project Atmosphere Canada offers a module to educate primary and secondary students about cloud formation and characteristics (1). The website outlines key points and offers a more in-depth discussion of water vapor, cloud formation, convection, air motion, severe weather, and more. The second website, by Scholastic, supplies many pdf documents of activities and lesson plans for all types of weather phenomena including clouds (2). Students can learn about condensation, discover what makes up a cloud, and find a key identifying the cloud types. Next, USA Today offers an online tutorial of the differing characteristics of clouds (3). Users can learn about Mammatus clouds, contrails, cloud seeding, and other cloud-related topics. At the fourth website, visitors can view meteorologist Dan Satterfield's amazing cloud photographs (4). Educators may find useful materials to supplement their lectures. Next, NASA's Climate and Radiation Branch furnishes "information on the fantastic variety of cloud forms and structures, and their implications for climate" (5). While the website is still being constructed, users can find useful information about the Bounded Cascades Fractal Cloud model, animations, and definitions of inhomogeneous cloud terminology. The sixth website, created by the National Center for Atmospheric Research and the University Corporation for Atmospheric Research, addresses how clouds impact our lives, how they cause chaos, and how they form (6). The enlightening descriptions are packed with colorful images and short quizzes. Next, The Australian Government's Bureau of Meteorology describes the useful of clouds as an indicator of weather conditions (7). After learning how moist air can form clouds, individuals can view images of the ten most common cloud types. Lastly, Enchanted Learning offers a table of the cloud types with their abbreviation, appearance, composition, and altitude along with explanations of cloud formation and the atmosphere (8). Educators can find simple activities dealing with cloud types and the water cycle.

  4. Horizontal winds derived from the polar mesospheric cloud images as observed by the CIPS instrument on the AIM satellite

    NASA Astrophysics Data System (ADS)

    Rong, P. P.; Yue, J.; Russell, J. M.; Lumpe, J. D.; Gong, J.; Wu, D. L.; Randall, C. E.

    2015-06-01

    A cloud pattern matching technique is applied to polar mesospheric cloud (PMC) images taken by the Cloud Imaging and Particle Size instrument (CIPS) to infer the wind velocities in the mesopause region. CIPS measurements are analyzed to detect patterns that repeat from one orbit to the next but are displaced in location; the displacement provides a measure of the wind velocity. Pattern matching is achieved by resampling the CIPS data to longitude and latitude grids with the grid-box size forced at ~5 km in both directions. The correlated patterns are searched within a geographic region referred to as a "frame" of ~500 km in longitude × 400 km in latitude. The histograms of the derived velocities indicate that easterly winds prevail, with a mean zonal wind of -20 to -15 m/s. Mean meridional winds are overall small, but in late summer the histogram indicated a poleward wind of ~20-30 m/s. The variability of CIPS cloud albedo on consecutive orbits is also examined at fixed geolocations. The statistical results suggest that ~86% of pairs underwent mean cloud albedo variation of < 50% on consecutive orbits, suggesting a moderate change. It is also found that the correlation of the cloud structures between two consecutive orbits at a fixed location is generally poor. These findings suggest that cloud patterns are subject to wind advection, but the cloud patches are more extended in size than the movement that occurs. Cloud voids are found to be more likely to remain at the same geolocations.

  5. Autoadaptive monospectral cloud identification in Meteosat satellite images

    NASA Astrophysics Data System (ADS)

    Boekaerts, Piet; Nyssen, E.; Cornelis, Jan P.

    1995-11-01

    A non-supervised, autoadaptive cloud identification scheme for mono-spectral Meteosat data is presented. The identification of clouds is equivalent to the assignment of meteorological meaningful labels to cloud regions. Automated cloud region detection is reduced to the problem of finding an algorithm that performs a data reduction on Meteosat images while optimally preserving cloud region information. A self-organizing 1D feature map applied to random segments of individual Meteosat channels is shown to meet the requirements of such algorithm. A study of the segment size indicates that small segment sizes are sufficient and even better than large segment sizes for consistent mono-spectral cloud region detection. This is explained in terms of the statistical properties of Meteosat images and the structural features of the code vectors (code segments) in the topological map. Decreasing the number of code segments used to reduce the information content of Meteosat channels results in a systematic, consistent loss of cloud region information.

  6. Structure and Nonrigid Motion Analysis of Satellite Cloud Images

    Microsoft Academic Search

    Lin Zhou; Chandra Kambhamettu

    1998-01-01

    This paper proposes a new method for recoveringnonrigid motion and structure of clouds under affineconstraints using time-varying cloud images obtainedfrom meteorological satellites. This problem is challengingnot only due to the correspondence problembut also due to the lack of depth cues in the 2D cloudimages (scaled orthographic projection). In this paper,affine motion is chosen as a suitable model forsmall local cloud

  7. Reproducing color images with embedded metallic patterns

    Microsoft Academic Search

    Roger D. Hersch; Fabien Collaud; Patrick Emmel

    2003-01-01

    By combining a metallic ink and standard inks, one may create printed images having a dynamic appearance: an image viewed under specular reflection may be considerably different from the same image viewed under non-specular reflection. Patterns which are either dark or hidden become highlighted under specular reflection, yielding interesting visual effects. To create such images, one needs to be able

  8. Mesopause Horizontal wind estimates based on AIM CIPS polar mesospheric cloud pattern matching

    NASA Astrophysics Data System (ADS)

    Rong, P.; Yue, J.; Russell, J. M.; Gong, J.; Wu, D. L.; Randall, C. E.

    2013-12-01

    A cloud pattern matching approach is used to estimate horizontal winds in the mesopause region using Polar Mesospheric Cloud (PMC) albedo data measured by the Cloud Imaging and Particle Size instrument on the AIM satellite. Measurements for all 15 orbits per day throughout July 2007 are used to achieve statistical significance. For each orbit, eighteen out of the twenty-seven scenes are used for the pattern matching operation. Some scenes at the lower latitudes are not included because there is barely any cloud coverage for these scenes. The frame-size chosen is about 12 degrees in longitude and 3 degrees in latitude. There is no strict criterion in choosing the frame size since PMCs are widespread in the polar region and most local patterns do not have a clearly defined boundary. The frame moves at a step of 1/6th of the frame size in both the longitudinal and latitudinal directions to achieve as many 'snap-shots' as possible. A 70% correlation is used as a criterion to define an acceptable match between two patterns at two time frames; in this case the time difference is about 3.6 minutes that spans every 5 'bowtie' scenes. A 70% criterion appears weak if the chosen pattern is expected to act like a tracer. It is known that PMC brightness varies rapidly with a changing temperature and water vapor environment or changing nucleation conditions, especially on smaller spatial scales; therefore PMC patterns are not ideal tracers. Nevertheless, within a short time span such as 3.6 minutes a 70% correlation is sufficient to identify two cloud patterns that come from the same source region, although the two patterns may exhibit a significant difference in the actual brightness. Analysis of a large number of matched cloud patterns indicates that over the 3.6-minute time span about 70% of the patterns remain in the same locations. Given the 25-km2 horizontal resolution of CIPS data, this suggests that the overall magnitude of horizontal wind at PMC altitudes (~80-87 km) in the polar summer cannot exceed 25 m/s. In other words, the wind detection resolution is no better than 25 m/s. There are about 10% of cases in which it appears that an easterly prevails, with a peak value at about 80-100m/s. In another 5% of cases a westerly appears to prevail. The remaining 15% cases are related to either invalid cloud features with poor background correction or the situation in which the matching occurs at the corners of the bowties. The AIM CIPS cloud pattern matching results overall suggest that higher wind speed (25-200 m/s) can be reached occasionally, while in a majority of cases the wind advection caused albedo change is much smaller than the in-situ albedo change. However, we must note that this analysis was a feasibility study and the short period analyzed may not be representative of the winds over a seasonal time scale or the multiple-year average.

  9. Novel approach to identify good tracer clouds from a sequence of satellite images

    Microsoft Academic Search

    Achintya K. Mandal; Srimanta Pal; Arun K. De; Subhasis Mitra

    2005-01-01

    A novel hierarchical method for finding tracer clouds from weather satellite images is proposed. From the sequence of cloud images, different features such as mean, standard deviation, busyness, and entropy are extracted. Based on these features, clouds are segmented using the k-means clustering algorithm and considering the coldest cloud segment, potential regions for tracer clouds are identified. These regions are

  10. Hazardous cloud imaging: a new way of using passive infrared.

    PubMed

    Flanigan, D F

    1997-09-20

    A modeling and simulation study of the limits of remote detection by passive IR has led to a new concept for the remote detection of hazardous clouds. A passive IR signature model was developed with the Edgewood Research, Development, and Engineering Center IR spectral data bases used as input for chemicals and biologicals and with the atmospheric transmittance model used for MODTRAN. The cloud travel and dispersion model, VLSTRACK, was used to simulate chemical and biological clouds. An easily applied spectral discrimination technique was developed with a standard Mathematica version of linear programming. All these were melded with Mathematica to produce images of three threat clouds: Sarin, mustard, and an unnamed biological. The hazardous cloud imager is a spatially scanning Fourier transform IR on the same level of complexity as conventional remote detectors, but is capable of greater sensitivity and moving operation. PMID:18259578

  11. Clouds

    NSDL National Science Digital Library

    In this scenario-based, problem-based learning (PBL) activity, students investigate cloud formation, cloud classification, and the role of clouds in heating and cooling the Earth; how to interpret TRMM (Tropical Rainfall Measuring Mission) images and data; and the role clouds play in the Earth’s radiant budget and climate. Students assume the role of weather interns in a state climatology office and assist a frustrated student in a homework assignment. Learning is supported by a cloud in a bottle and an ice-albedo demonstration, a three-day cloud monitoring outdoor activity, and student journal assignments. The hands-on activities require two 2-liter soda bottles, an infrared heat lamp, and two thermometers. The resource includes a teacher's guide, questions and answer key, assessment rubric, glossary, and an appendix with information supporting PBL in the classroom.

  12. Automatic cloud coverage assessment of Formosat-2 image

    NASA Astrophysics Data System (ADS)

    Hsu, Kuo-Hsien

    2011-11-01

    Formosat-2 satellite equips with the high-spatial-resolution (2m ground sampling distance) remote sensing instrument. It has been being operated on the daily-revisiting mission orbit by National Space organization (NSPO) of Taiwan since May 21 2004. NSPO has also serving as one of the ground receiving stations for daily processing the received Formosat- 2 images. The current cloud coverage assessment of Formosat-2 image for NSPO Image Processing System generally consists of two major steps. Firstly, an un-supervised K-means method is used for automatically estimating the cloud statistic of Formosat-2 image. Secondly, manual estimation of cloud coverage from Formosat-2 image is processed by manual examination. Apparently, a more accurate Automatic Cloud Coverage Assessment (ACCA) method certainly increases the efficiency of processing step 2 with a good prediction of cloud statistic. In this paper, mainly based on the research results from Chang et al, Irish, and Gotoh, we propose a modified Formosat-2 ACCA method which considered pre-processing and post-processing analysis. For pre-processing analysis, cloud statistic is determined by using un-supervised K-means classification, Sobel's method, Otsu's method, non-cloudy pixels reexamination, and cross-band filter method. Box-Counting fractal method is considered as a post-processing tool to double check the results of pre-processing analysis for increasing the efficiency of manual examination.

  13. An enhanced neighborhood similar pixel interpolator approach for removing thick clouds in landsat images

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thick cloud contaminations in Landsat images limit their regular usage for land applications. A few methods have been developed to remove thick clouds using additional cloud-free images. Unfortunately, the cloud-free composition image produced by existing methods commonly lacks from the desired spat...

  14. Quantitative Comparison of Dense Cloud Detection of an Evolutionary Image Classification Algorithm to the MODIS Cloud Mask and to the VIIRS Cloud Mask

    Microsoft Academic Search

    H. G. Momm; G. Easson

    2006-01-01

    The proper identification of cloud cover plays an important role for the accurate determination of atmospheric and surface parameters from remotely sensed data. The MODIS (Moderate Resolution Imaging Spectroradiometer) cloud mask algorithm has been used by NASA and other governmental agencies as input for models, analysis systems, and decision support tools. The Visible Infrared Imager Radiometer Suite (VIIRS) cloud mask

  15. Image segmentation based on data field and cloud model

    NASA Astrophysics Data System (ADS)

    Qin, Kun; Ou, Leihai; Wu, Tao; Du, Yi

    2010-08-01

    There are many uncertainties in image segmentation, which needs theories and methods with uncertainty to handle. This paper proposes a novel method of image segmentation based on data field and cloud model, which considers the spatial information of image through data field, and handles the uncertainty of image through cloud model. The proposed method inspired from cognitive physics considers each pixel as a physical object, calculates the interactive force of these physical objects, and generates image data field and the potential values which are considered as spatial information. And then, uses cloud transformation and magnitude cloud synthesis to extract the concepts of potential-frequency histogram from low level to high level, realizes the clustering of pixels, finally uses maximum determination to partition the pixels into different classes and segment image into different regions. Results of many experiments indicate that the proposed method obtains better effect than those of Fuzzy C-means clustering, Otsu and cloud based hierarchical method, and it is feasible and effective.

  16. HI Imaging of the Large Magellanic Cloud

    E-print Network

    S. Kim; L. Staveley-Smith; R. J. Sault

    2000-09-19

    We present results from the combined Australia Telescope Compact Array (ATCA) aperture synthesis mosaic survey of HI emission in the Large Magellanic Cloud with 64m Parkes single dish telescope observations.

  17. Climatic shift in patterns of shallow clouds over the Amazon

    NASA Astrophysics Data System (ADS)

    Chagnon, F. J. F.; Bras, R. L.; Wang, J.

    2004-12-01

    The Amazon rain forest has experienced dramatic changes in the past 50 years due to active deforestation. As of 2001, 15% of the 4,000,000 km2 Brazilian Amazon has been deforested [Instituto Nacional de Pesquisas Espaciais (INPE), 2003]; each year, agricultural exploitation claims an estimated 13,000 km2 of tropical forest [Achard et al., 2002]. In this paper we investigate the climatic effects caused by the observed change of the physical characteristics of the land surface (i.e., increased surface albedo, decreased root-zone depth, decreased surface roughness and decreased leaf-area index). More precisely, we examine the spatial correspondence of shallow cumulus clouds with deforestation. Through the creation of an 8-year record of thrice daily shallow cumulus cloud cover at 1 km resolution from multi-spectral satellite imagery, we quantitatively show the existence of a significant climatic shift in shallow cloudiness patterns associated with deforestation. This shift manifests itself as an enhancement of shallow cumuli over deforested patches, and has potentially important climatic, hydrologic and ecological implications.

  18. The radiative consistency of Atmospheric Infrared Sounder and Moderate Resolution Imaging Spectroradiometer cloud retrievals

    NASA Astrophysics Data System (ADS)

    Kahn, Brian H.; Fishbein, Evan; Nasiri, Shaima L.; Eldering, Annmarie; Fetzer, Eric J.; Garay, Michael J.; Lee, Sung-Yung

    2007-05-01

    The consistency of cloud top temperature (TC) and effective cloud fraction (f) retrieved by the Atmospheric Infrared Sounder (AIRS)/Advanced Microwave Sounding Unit (AMSU) observation suite and the Moderate Resolution Imaging Spectroradiometer (MODIS) on the EOS-Aqua platform are investigated. Collocated AIRS and MODIS TC and f are compared via an "effective scene brightness temperature" (Tb,e). Tb,e is calculated with partial field of view (FOV) contributions from TC and surface temperature (TS), weighted by f and 1-f, respectively. AIRS reports up to two cloud layers while MODIS reports up to one. However, MODIS reports TC, TS, and f at a higher spatial resolution than AIRS. As a result, pixel-scale comparisons of TC and f are difficult to interpret, demonstrating the need for alternatives such as Tb,e. AIRS-MODIS Tb,e differences (?Tb,e) for identical observing scenes are useful as a diagnostic for cloud quantity comparisons. The smallest values of ?Tb,e are for high and opaque clouds, with increasing scatter in ?Tb,e for clouds of smaller opacity and lower altitude. A persistent positive bias in ?Tb,e is observed in warmer and low-latitude scenes, characterized by a mixture of MODIS CO2 slicing and 11-?m window retrievals. These scenes contain heterogeneous cloud cover, including mixtures of multilayered cloudiness and misplaced MODIS cloud top pressure. The spatial patterns of ?Tb,e are systematic and do not correlate well with collocated AIRS-MODIS radiance differences, which are more random in nature and smaller in magnitude than ?Tb,e. This suggests that the observed inconsistencies in AIRS and MODIS cloud fields are dominated by retrieval algorithm differences, instead of differences in the observed radiances. The results presented here have implications for the validation of cloudy satellite retrieval algorithms, and use of cloud products in quantitative analyses.

  19. Conjecture on imminent earthquake prediction --- from shaving foam to cloud patterns

    E-print Network

    Liu, Xin

    2013-01-01

    A conjecture on imminent earthquake prediction is presented. Drastic geological deformations of crustal rock strata taking place immediately (hours/days) before an earthquake may cause fast air or gas emission/absorption vertically in between ground and sky. I conjecture, inspired by an observation of strange patterns appearing on shaving foam, that this fast movement of air fluid may produce unusual cloud patterns at interfaces between atmosphere levels. This air movement is vertical and drastic, different from the horizontal and moderate meteorological air movement, hence its caused cloud patterns are expected to be different from meteorological cloud patterns. This provides a possible origin for the so-called earthquake cloud. Recognition of different earthquake cloud patterns may provide a practical way to estimate location, magnitude and strength of geological deformations of rock strata, and hence a method with support of physics for imminent earthquake prediction. In the end of this paper an experiment...

  20. Design patterns in medical imaging information systems

    Microsoft Academic Search

    Kent S. Hoo; Stephen T. Wong; Kenneth D. Laxer; Robert C. Knowlton; Wan Ching

    2000-01-01

    The purpose of this paper is to introduce a new and important conceptual framework of software design for the medical imaging community using design patterns. Use cases are created to summarize operational scenarios of clinicians using the system to complete certain tasks such as image segmentation. During design the Unified Modeling Language is used to translate the use cases into

  1. Fringe pattern denoising via image decomposition.

    PubMed

    Fu, Shujun; Zhang, Caiming

    2012-02-01

    Filtering off noise from a fringe pattern is one of the key tasks in optical interferometry. In this Letter, using some suitable function spaces to model different components of a fringe pattern, we propose a new fringe pattern denoising method based on image decomposition. In our method, a fringe image is divided into three parts: low-frequency fringe, high-frequency fringe, and noise, which are processed in different spaces. An adaptive threshold in wavelet shrinkage involved in this algorithm improves its denoising performance. Simulation and experimental results show that our algorithm obtains smooth and clean fringes with different frequencies while preserving fringe features effectively. PMID:22297373

  2. Images from Galileo of the Venus cloud deck

    USGS Publications Warehouse

    Belton, M.J.S.; Gierasch, P.J.; Smith, M.D.; Helfenstein, P.; Schinder, P.J.; Pollack, James B.; Rages, K.A.; Ingersoll, A.P.; Klaasen, K.P.; Veverka, J.; Anger, C.D.; Carr, M.H.; Chapman, C.R.; Davies, M.E.; Fanale, F.P.; Greeley, R.; Greenberg, R.; Head, J. W., III; Morrison, D.; Neukum, G.; Pilcher, C.B.

    1991-01-01

    Images of Venus taken at 418 (violet) and 986 [near-infrared (NIR)] nanometers show that the morphology and motions of large-scale features change with depth in the cloud deck. Poleward meridional velocities, seen in both spectral regions, are much reduced in the NIR. In the south polar region the markings in the two wavelength bands are strongly anticorrelated. The images follow the changing state of the upper cloud layer downwind of the subsolar point, and the zonal flow field shows a longitudinal periodicity that may be coupled to the formation of large-scale planetary waves. No optical lightning was detected.

  3. Secure public cloud platform for medical images sharing.

    PubMed

    Pan, Wei; Coatrieux, Gouenou; Bouslimi, Dalel; Prigent, Nicolas

    2015-01-01

    Cloud computing promises medical imaging services offering large storage and computing capabilities for limited costs. In this data outsourcing framework, one of the greatest issues to deal with is data security. To do so, we propose to secure a public cloud platform devoted to medical image sharing by defining and deploying a security policy so as to control various security mechanisms. This policy stands on a risk assessment we conducted so as to identify security objectives with a special interest for digital content protection. These objectives are addressed by means of different security mechanisms like access and usage control policy, partial-encryption and watermarking. PMID:25991144

  4. Designing SCIT Architecture Pattern in a Cloud-based Environment

    E-print Network

    Sood, Arun K.

    C-SCIT (Cloud- based Self-Cleansing Intrusion Tolerant) scheme that can provide enhanced intrusion. The main contribution of this paper is to design a Cloud- based Self-Cleansing Intrusion Tolerance (C

  5. Describing the NPOESS Preparatory Project Visible/Infrared Imaging Radiometer Suite (VIIRS) Cloud Environmental Data Records

    NASA Astrophysics Data System (ADS)

    Hoffman, C.; Guenther, B.; Kilcoyne, H.; Mineart, G.; St. Germain, K.; Reed, B.

    2008-12-01

    The Visible/Infrared Imaging Radiometer Suite (VIIRS) is one of the instruments that make up the suite of sensors on the NPOESS Preparatory Project (NPP) scheduled to launch in 2010. VIIRS will produce seven Environmental Data Records (EDRs) describing cloud properties. The VIIRS Cloud EDRs include the Cloud Optical Thickness (COT), Cloud Effective Particle Size Parameter (CEPS), Cloud Top Pressure (CTP), Cloud Top Height (CTH), Cloud Top Temperature (CTT), Cloud Cover/Layers (CCL), and Cloud Base Height (CBH). This paper will describe the VIIRS algorithms used to generate these EDRs and provide a current estimate of performance based on pre-Launch test data.

  6. An Adaptive System to Diminish the Influence of Clouds in Satellite Images for Texture Segmentation

    E-print Network

    Lewiner, Thomas (Thomas Lewiner)

    of clouds in satellite images, allowing the computer vision system to check in an easier way whatAn Adaptive System to Diminish the Influence of Clouds in Satellite Images for Texture an approach to reduce the influence of clouds in satellite images. The developed implementation

  7. Feeding People's Curiosity: Leveraging the Cloud for Automatic Dissemination of Mars Images

    NASA Technical Reports Server (NTRS)

    Knight, David; Powell, Mark

    2013-01-01

    Smartphones and tablets have made wireless computing ubiquitous, and users expect instant, on-demand access to information. The Mars Science Laboratory (MSL) operations software suite, MSL InterfaCE (MSLICE), employs a different back-end image processing architecture compared to that of the Mars Exploration Rovers (MER) in order to better satisfy modern consumer-driven usage patterns and to offer greater server-side flexibility. Cloud services are a centerpiece of the server-side architecture that allows new image data to be delivered automatically to both scientists using MSLICE and the general public through the MSL website (http://mars.jpl.nasa.gov/msl/).

  8. Cloud Detection with the Earth Polychromatic Imaging Camera (EPIC)

    NASA Technical Reports Server (NTRS)

    Meyer, Kerry; Marshak, Alexander; Lyapustin, Alexei; Torres, Omar; Wang, Yugie

    2011-01-01

    The Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR) would provide a unique opportunity for Earth and atmospheric research due not only to its Lagrange point sun-synchronous orbit, but also to the potential for synergistic use of spectral channels in both the UV and visible spectrum. As a prerequisite for most applications, the ability to detect the presence of clouds in a given field of view, known as cloud masking, is of utmost importance. It serves to determine both the potential for cloud contamination in clear-sky applications (e.g., land surface products and aerosol retrievals) and clear-sky contamination in cloud applications (e.g., cloud height and property retrievals). To this end, a preliminary cloud mask algorithm has been developed for EPIC that applies thresholds to reflected UV and visible radiances, as well as to reflected radiance ratios. This algorithm has been tested with simulated EPIC radiances over both land and ocean scenes, with satisfactory results. These test results, as well as algorithm sensitivity to potential instrument uncertainties, will be presented.

  9. A secure online image trading system for untrusted cloud environments.

    PubMed

    Munadi, Khairul; Arnia, Fitri; Syaryadhi, Mohd; Fujiyoshi, Masaaki; Kiya, Hitoshi

    2015-01-01

    In conventional image trading systems, images are usually stored unprotected on a server, rendering them vulnerable to untrusted server providers and malicious intruders. This paper proposes a conceptual image trading framework that enables secure storage and retrieval over Internet services. The process involves three parties: an image publisher, a server provider, and an image buyer. The aim is to facilitate secure storage and retrieval of original images for commercial transactions, while preventing untrusted server providers and unauthorized users from gaining access to true contents. The framework exploits the Discrete Cosine Transform (DCT) coefficients and the moment invariants of images. Original images are visually protected in the DCT domain, and stored on a repository server. Small representation of the original images, called thumbnails, are generated and made publicly accessible for browsing. When a buyer is interested in a thumbnail, he/she sends a query to retrieve the visually protected image. The thumbnails and protected images are matched using the DC component of the DCT coefficients and the moment invariant feature. After the matching process, the server returns the corresponding protected image to the buyer. However, the image remains visually protected unless a key is granted. Our target application is the online market, where publishers sell their stock images over the Internet using public cloud servers. PMID:26090324

  10. Distortion of the HBT images by meson clouds

    E-print Network

    K. Hattori; T. Matsui

    2009-09-11

    We study the effects of mesonic final state interactions on the Hanbury Brown and Twiss (HBT) intensity interferometry for mesons in ultra-relativistic heavy ion collisions. Modification of the one-body amplitude of emitted mesons while going through a cloud of other mesons is estimated in the semiclassical approximation with a mesonic optical potential which incorporates both coherent forward scattering with other mesons and the absorption due to the incoherent scattering in the meson clouds. We show how these effects results in the distortion of the HBT images.

  11. The algorithm to generate color point-cloud with the registration between panoramic image and laser point-cloud

    NASA Astrophysics Data System (ADS)

    Zeng, Fanyang; Zhong, Ruofei

    2014-03-01

    Laser point cloud contains only intensity information and it is necessary for visual interpretation to obtain color information from other sensor. Cameras can provide texture, color, and other information of the corresponding object. Points with color information of corresponding pixels in digital images can be used to generate color point-cloud and is conducive to the visualization, classification and modeling of point-cloud. Different types of digital cameras are used in different Mobile Measurement Systems (MMS).the principles and processes for generating color point-cloud in different systems are not the same. The most prominent feature of the panoramic images is the field of 360 degrees view angle in the horizontal direction, to obtain the image information around the camera as much as possible. In this paper, we introduce a method to generate color point-cloud with panoramic image and laser point-cloud, and deduce the equation of the correspondence between points in panoramic images and laser point-clouds. The fusion of panoramic image and laser point-cloud is according to the collinear principle of three points (the center of the omnidirectional multi-camera system, the image point on the sphere, the object point). The experimental results show that the proposed algorithm and formulae in this paper are correct.

  12. Design patterns in medical imaging information systems

    NASA Astrophysics Data System (ADS)

    Hoo, Kent S., Jr.; Wong, Stephen T. C.; Laxer, Kenneth D.; Knowlton, Robert C.; Ching, Wan

    2000-05-01

    The purpose of this paper is to introduce a new and important conceptual framework of software design for the medical imaging community using design patterns. Use cases are created to summarize operational scenarios of clinicians using the system to complete certain tasks such as image segmentation. During design the Unified Modeling Language is used to translate the use cases into modeling diagrams that describe how the system functions. Next, design patterns are applied to build models that describe how software components interoperate to deliver that functionality. The software components are implemented using the Java language, CORBA architecture, and other web technologies. The biomedical image information system is used in epilepsy neurosurgical planning and diagnosis. This article proposes the use of proven software design models for solving medical imaging informatics design problems. Design patterns provide an excellent vehicle to leverage design solutions that have worked in the past to solve the problems we face in building user-friendly, reliable, and efficient information systems. This work introduces this new technology for building increasing complex medical image information systems. The rigorous application of software design techniques is essential in building information systems that are easy to use, rich in functionality, maintainable, reliable, and updatable.

  13. Leveraging the Cloud for Robust and Efficient Lunar Image Processing

    NASA Technical Reports Server (NTRS)

    Chang, George; Malhotra, Shan; Wolgast, Paul

    2011-01-01

    The Lunar Mapping and Modeling Project (LMMP) is tasked to aggregate lunar data, from the Apollo era to the latest instruments on the LRO spacecraft, into a central repository accessible by scientists and the general public. A critical function of this task is to provide users with the best solution for browsing the vast amounts of imagery available. The image files LMMP manages range from a few gigabytes to hundreds of gigabytes in size with new data arriving every day. Despite this ever-increasing amount of data, LMMP must make the data readily available in a timely manner for users to view and analyze. This is accomplished by tiling large images into smaller images using Hadoop, a distributed computing software platform implementation of the MapReduce framework, running on a small cluster of machines locally. Additionally, the software is implemented to use Amazon's Elastic Compute Cloud (EC2) facility. We also developed a hybrid solution to serve images to users by leveraging cloud storage using Amazon's Simple Storage Service (S3) for public data while keeping private information on our own data servers. By using Cloud Computing, we improve upon our local solution by reducing the need to manage our own hardware and computing infrastructure, thereby reducing costs. Further, by using a hybrid of local and cloud storage, we are able to provide data to our users more efficiently and securely. 12 This paper examines the use of a distributed approach with Hadoop to tile images, an approach that provides significant improvements in image processing time, from hours to minutes. This paper describes the constraints imposed on the solution and the resulting techniques developed for the hybrid solution of a customized Hadoop infrastructure over local and cloud resources in managing this ever-growing data set. It examines the performance trade-offs of using the more plentiful resources of the cloud, such as those provided by S3, against the bandwidth limitations such use encounters with remote resources. As part of this discussion this paper will outline some of the technologies employed, the reasons for their selection, the resulting performance metrics and the direction the project is headed based upon the demonstrated capabilities thus far.

  14. Body image and eating patterns among adolescents

    PubMed Central

    2013-01-01

    Background Data on the association between body self-perception and eating patterns among adolescents are scarce. This study assessed the association between body image and eating patterns among normal-weight, overweight and obese adolescents. Methods A cross-sectional survey (n = 1231; 12–17 years old) was carried out in the Balearic Islands, Spain. Anthropometry, body image, socio-economic determinants, and food consumption were studied. Results Fifty-one percent of boys and sixty percent of girls that wished to be thinner had less than or equal to 3 eating occasions per day. Overfat girls that wish to be thinner skipped breakfast more frequently than normal-fat girls. Overfat boys and girls that wished a thinner body reported lower consumption of several food groups than normal-fat adolescents and overfat boys satisfied with their own body image (i.e. breakfast cereals, pasta and rice dishes, other oils and fats, high fat foods, soft drinks and chocolates in boys; and dairy products and chocolates in girls).A restriction of Western diet foods and energy intake was associated with a wish to be thinner among overfat adolescents. Conclusions Many overfat boys were satisfied with their body image while practically all overfat girls reported wishing a thinner body. Meal patterns and food consumption were associated with body dissatisfaction and overfat status among adolescents. PMID:24289180

  15. Cloud based toolbox for image analysis, processing and reconstruction tasks.

    PubMed

    Bednarz, Tomasz; Wang, Dadong; Arzhaeva, Yulia; Lagerstrom, Ryan; Vallotton, Pascal; Burdett, Neil; Khassapov, Alex; Szul, Piotr; Chen, Shiping; Sun, Changming; Domanski, Luke; Thompson, Darren; Gureyev, Timur; Taylor, John A

    2015-01-01

    This chapter describes a novel way of carrying out image analysis, reconstruction and processing tasks using cloud based service provided on the Australian National eResearch Collaboration Tools and Resources (NeCTAR) infrastructure. The toolbox allows users free access to a wide range of useful blocks of functionalities (imaging functions) that can be connected together in workflows allowing creation of even more complex algorithms that can be re-run on different data sets, shared with others or additionally adjusted. The functions given are in the area of cellular imaging, advanced X-ray image analysis, computed tomography and 3D medical imaging and visualisation. The service is currently available on the website www.cloudimaging.net.au . PMID:25381109

  16. Cultural Relic 3D Reconstruction from Digital Images and Laser Point Clouds

    Microsoft Academic Search

    Jie Liu; Jianqing Zhang; Jia Xu

    2008-01-01

    This paper proposes a method to combine the digital images and Laser point clouds to reconstruct the 3D model of the archaic glockenspiel. All the stations of the Laser point clouds are connected according to the ICP arithmetic. Then image matching is used to register the high resolution digital images and the Laser synchronous images to gain the corresponding texture

  17. High-Resolution Images of Diffuse Neutral Clouds in the Milky Way. I. Observations, Imaging, and Basic Cloud Properties

    E-print Network

    Pidopryhora, Yurii; Dickey, John M; Rupen, Michael P

    2015-01-01

    A set of diffuse interstellar clouds in the inner Galaxy within a few hundred pc of the Galactic plane has been observed at an angular resolution of ~1 arcmin combining data from the NRAO Green Bank Telescope and the Very Large Array. At the distance of the clouds the linear resolution ranges from ~1.9 pc to ~2.8 pc. These clouds have been selected to be somewhat out of the Galactic plane and are thus not confused with unrelated emission, but in other respects they are a Galactic population. They are located near the tangent points in the inner Galaxy, and thus at a quantifiable distance: $2.3 \\leq R \\leq 6.0$ kpc from the Galactic Center, and $-1000 \\leq z \\leq +610$ pc from the Galactic plane. These are the first images of the diffuse neutral HI clouds that may constitute a considerable fraction of the ISM. Peak HI column densities range from $N_{HI} = 0.8-2.9 \\times 10^{20}$ cm$^{-2}$. Cloud diameters vary between about 10 and 100 pc, and their HI mass spans the range from less than a hundred to a few thou...

  18. Optical and Near IR Imaging of the Rosette Molecular Cloud

    NASA Astrophysics Data System (ADS)

    Phelps, Randy L.

    1993-12-01

    Optical VRI and infrared JHK images of the region near the IRAS source 06314+0427, which lies within the Rosette Molecular Cloud (RMC), near the CO peak as observed by Blitz & Stark 1986, have been obtained to investigate star formation in that region. The images clearly show the boundary of the cloud against the H? emission from the Rosette nebula. The images also reveal a partially embedded cluster, not coincident with the IRAS source, along the edge of the molecular cloud. Two comet-like objects are seen in emission and a highly reddened point-source (V-I > 3), coincident with IRAS 06314+0427, is found among a small aggregate of stars (see also Block, Gaballe & Dyson 1993). The IR colors suggest that many of the stars are PMS stars with at least one source being a candidate Herbig Ae/Be star (see also Hanson et al. 1993). References Blitz, L. & Stark, A. A. 1986, ApJ, 300, L89 Block, D. L., Geballe, T. R. & Dyson, J. E. 1993, A&A, 273, L41 Hanson, M. M., Geballe, T. R., Conti, P. S. & Block, D. L. 1993, A&A, 273, L44

  19. Voyager imaging of Triton's clouds and hazes

    NASA Technical Reports Server (NTRS)

    Rages, Kathy; Pollack, James B.

    1992-01-01

    Results are presented from a detailed analysis of Voyager images of Triton obtained at the highest solar phase angles; these have been fit to Mie scattering models in order to obtain the mean particle sizes, number densities, and the vertical extent of the two different scattering components of the Triton atmosphere. The 0.001-0.01 optical depths of about 0.17 micron particles are vertically distributed with scale heights of about 10 km throughout Triton. A number of properties of the haze particles in question suggest that they are composed of photochemically produced gases which have condensed in the cold lower atmosphere of Triton.

  20. High Quality Typhoon Cloud Image Restoration by Combining Genetic Algorithm with Contourlet Transform

    SciTech Connect

    Zhang Changjiang; Wang Xiaodong [College of Mathematics, Physics and Information Engineering, Zhejiang Normal University, Jinhua (China)

    2008-11-06

    An efficient typhoon cloud image restoration algorithm is proposed. Having implemented contourlet transform to a typhoon cloud image, noise is reduced in the high sub-bands. Weight median value filter is used to reduce the noise in the contourlet domain. Inverse contourlet transform is done to obtain the de-noising image. In order to enhance the global contrast of the typhoon cloud image, in-complete Beta transform (IBT) is used to determine non-linear gray transform curve so as to enhance global contrast for the de-noising typhoon cloud image. Genetic algorithm is used to obtain the optimal gray transform curve. Information entropy is used as the fitness function of the genetic algorithm. Experimental results show that the new algorithm is able to well enhance the global for the typhoon cloud image while well reducing the noises in the typhoon cloud image.

  1. Enabling outsourcing XDS for imaging on the public cloud.

    PubMed

    Ribeiro, Luís S; Rodrigues, Renato P; Costa, Carlos; Oliveira, José Luís

    2013-01-01

    Picture Archiving and Communication System (PACS) has been the main paradigm in supporting medical imaging workflows during the last decades. Despite its consolidation, the appearance of Cross-Enterprise Document Sharing for imaging (XDS-I), within IHE initiative, constitutes a great opportunity to readapt PACS workflow for inter-institutional data exchange. XDS-I provides a centralized discovery of medical imaging and associated reports. However, the centralized XDS-I actors (document registry and repository) must be deployed in a trustworthy node in order to safeguard patient privacy, data confidentiality and integrity. This paper presents XDS for Protected Imaging (XDS-p), a new approach to XDS-I that is capable of being outsourced (e.g. Cloud Computing) while maintaining privacy, confidentiality, integrity and legal concerns about patients' medical information. PMID:23920510

  2. Reflections on current and future applications of multiangle imaging to aerosol and cloud remote sensing

    NASA Astrophysics Data System (ADS)

    Diner, David

    2010-05-01

    The Multi-angle Imaging SpectroRadiometer (MISR) instrument has been collecting global Earth data from NASA's Terra satellite since February 2000. With its 9 along-track view angles, 4 spectral bands, intrinsic spatial resolution of 275 m, and stable radiometric and geometric calibration, no instrument that combines MISR's attributes has previously flown in space, nor is there is a similar capability currently available on any other satellite platform. Multiangle imaging offers several tools for remote sensing of aerosol and cloud properties, including bidirectional reflectance and scattering measurements, stereoscopic pattern matching, time lapse sequencing, and potentially, optical tomography. Current data products from MISR employ several of these techniques. Observations of the intensity of scattered light as a function of view angle and wavelength provide accurate measures of aerosol optical depths (AOD) over land, including bright desert and urban source regions. Partitioning of AOD according to retrieved particle classification and incorporation of height information improves the relationship between AOD and surface PM2.5 (fine particulate matter, a regulated air pollutant), constituting an important step toward a satellite-based particulate pollution monitoring system. Stereoscopic cloud-top heights provide a unique metric for detecting interannual variability of clouds and exceptionally high quality and sensitivity for detection and height retrieval for low-level clouds. Using the several-minute time interval between camera views, MISR has enabled a pole-to-pole, height-resolved atmospheric wind measurement system. Stereo imagery also makes possible global measurement of the injection heights and advection speeds of smoke plumes, volcanic plumes, and dust clouds, for which a large database is now available. To build upon what has been learned during the first decade of MISR observations, we are evaluating algorithm updates that not only refine retrieval accuracies but also include enhancements (e.g., finer spatial resolution) that would have been computationally prohibitive just ten years ago. In addition, we are developing technological building blocks for future sensors that enable broader spectral coverage, wider swath, and incorporation of high-accuracy polarimetric imaging. Prototype cameras incorporating photoelastic modulators have been constructed. To fully capitalize on the rich information content of the current and next-generation of multiangle imagers, several algorithmic paradigms currently employed need to be re-examined, e.g., the use of aerosol look-up tables, neglect of 3-D effects, and binary partitioning of the atmosphere into "cloudy" or "clear" designations. Examples of progress in algorithm and technology developments geared toward advanced application of multiangle imaging to remote sensing of aerosols and clouds will be presented.

  3. Automated detecting and removing cloud shadows in full-disk solar images

    NASA Astrophysics Data System (ADS)

    Feng, Song; Lin, Jiaben; Yang, Yunfei; Zhu, Haibo; Wang, Feng; Ji, Kaifan

    2014-10-01

    Sky clouds affect full-disk solar observations significantly. Their shadows obscure the details of solar features in observed images. Cloud-covered images are difficult to be used for further research without pre-processing. We proposed a technique for detecting and removing cloud shadows in full-disk solar images. In the detection procedure, a two-step approach is applied: (1) identifying the deviation of a cloud-covered image from a perfect disk; (2) quantifying the cloud cover by an index that we defined in this paper. In the removal procedure, the transmittance of clouds is measured by comparing the cloud-covered image with a "Quiet Sun" that getting from a normal observation. A restored cloud-free image can be obtained after correcting the absorption by clouds. We tested the procedures using the full-disk solar H ? images of the Global Oscillation Network Group (GONG), and utilized the structural similarity (SSIM) algorithm for evaluating the performance of image restoration. The results demonstrate that both procedures are significant effective, and that the cloud-covered image is restored not only in visual effect but also in intensities of solar features.

  4. MY NASA DATA: Cloud Patterns in Toronto, Ontario, Canada

    NSDL National Science Digital Library

    In this data activity, students explore trends in cloud coverage over Toronto, Ontario, Canada and learn about different cloud types. Step-by-step instructions for use of the MY NASA DATA Live Access Server (LAS) guide students through selecting a data set, importing the data into a spreadsheet, creating graphs, and analyzing data plots. The lesson provides detailed procedures, related links and sample graphs, follow-up questions, extensions, and teacher notes. Designed for student use, MY NASA DATA LAS samples micro datasets from large scientific data archives, and provides structured investigations engaging students in exploration of real data to answer real world questions.

  5. The Earth Clouds and Radiation Explorer (EarthCARE) Mission: Cloud and Aerosol Lidar and Imager algorithms.

    NASA Astrophysics Data System (ADS)

    Donovan, David; van Zadelhoff, Gerd-Jan; Wandinger, Ulla; Hünerbein, Anjah; Fischer, Jurgen; von Bismarck, Jonas; Eisinger, Michael; Lajas, Dulce; Wehr, Tobias

    2015-04-01

    The value of multi-sensor remote sensing applied to clouds and aerosol has become clear in recent years. For example, combinations of instruments including passive radiometers, lidars and cloud radars have proved invaluable for their ability to retrieve profiles of cloud macrophysical and microphysical properties. This is amply illustrated by various results from the US-DoE ARM (and similar) surface sites as well as results from data collected by sensors aboard the A-train satellites CloudSat, CALIPSO, and Terra. The Earth Clouds Aerosol and Radiation Explorer (EarthCARE) mission is a combined ESA/JAXA mission to be launched in 2018 which has been designed with sensor-synergy playing a key role. The mission consists of a cloud-profiling radar (CPR), a high-spectral resolution cloud/aerosol lidar (ATLID), a cloud/aerosol multi-spectral imager (MSI), and a three-view broad-band radiometer (BBR). The mission will deliver cloud, aerosol and radiation products focusing on horizontal scales ranging from 1 km to 10 km. EarthCARE data will be used in multiple ways ranging from model evaluation studies, to GCM-orientated cloud microphysical property parameterization development, to data assimilation activities. Recently a number of activities, funded by ESA, have kicked-off which will ultimately deliver operational algorithms for EarthCARE. One of these activities is the "Atmospheric Products from Imager and Lidar" (APRIL) project which focuses on the development of lidar, imager and combined lidar-imager cloud and aerosol algorithms. In this presentation an overview of the APRIL algorithms within the wider context of the planned EarthCARE processing chain will be given.

  6. Analysis of interstellar cloud structure based on IRAS images

    NASA Technical Reports Server (NTRS)

    Scalo, John M.

    1992-01-01

    The goal of this project was to develop new tools for the analysis of the structure of densely sampled maps of interstellar star-forming regions. A particular emphasis was on the recognition and characterization of nested hierarchical structure and fractal irregularity, and their relation to the level of star formation activity. The panoramic IRAS images provided data with the required range in spatial scale, greater than a factor of 100, and in column density, greater than a factor of 50. In order to construct densely sampled column density maps of star-forming clouds, column density images of four nearby cloud complexes were constructed from IRAS data. The regions have various degrees of star formation activity, and most of them have probably not been affected much by the disruptive effects of young massive stars. The largest region, the Scorpius-Ophiuchus cloud complex, covers about 1000 square degrees (it was subdivided into a few smaller regions for analysis). Much of the work during the early part of the project focused on an 80 square degree region in the core of the Taurus complex, a well-studied region of low-mass star formation.

  7. Venus: cloud level circulation during 1982 as determined from Pioneer cloud photopolarimeter images. I. Time and zonally averaged circulation

    SciTech Connect

    Limaye, S.S.; Grassotti, C.; Kuetemeyer, M.J.

    1988-02-01

    Significant mean cloud level circulation changes since 1974, noted in 1982 Venus cloud motion observations, have been validated by independent measurements of cloud motions in nearly-identical sets of images; agreement is obtained not only for the average zonal and meridional components, but for the eddy circulation's meridional transport of momentum. In contrast to 1979 observations, the time latitudinal profile and the longitudinally-averaged zonal component of the cloud motions for 1982 exhibit jets near 45 deg latitude in both the northern and southern hemispheres. 30 references.

  8. Chemical Imaging of Molecular Clouds and Comets with the FCRAO 14m Telescope

    NASA Astrophysics Data System (ADS)

    Schloerb, F. Peter

    1999-10-01

    Focal plane array receivers enable single dish telescopes to obtain sensitive maps of sources efficiently. In this paper, we summarize results of the detailed mapping of the chemistry of molecular cloud cores and comets with the focal plane array on the FCRAO 14m antenna by a number of investigators. Surveys of the emission from approximately 20 different molecular species have been carried out in GMC cores and dark clouds. The GMC core chemistry is remarkably homogeneous and rather similar from source to source. Time dependent chemical modelling finds good agreement with the observations at early evolutionary stages (t ~ 105 yr) suggesting that the GMC cores are dynamically evolving objects. Surveys of dark cloud cores have revealed significant abundance variations within the sources. The pattern of variations is best explained by small differences in the chemical evolutionary age within the source, with a typical value for the entire cloud also in the vicinity of ~105 years. Images of the molecular emission from comets provide important clues about the physical processes and chemistry of the cometary coma. Chemical models reveal that HCO+ is created in the coma via ion-molecule chemistry; its detailed distribution reflects its interaction with the solar wind and provides important tests of MHD models of these effects.

  9. Global Moderate Resolution Imaging Spectroradiometer (MODIS) cloud detection and height evaluation using CALIOP

    E-print Network

    Sheridan, Jennifer

    Global Moderate Resolution Imaging Spectroradiometer (MODIS) cloud detection and height evaluation with Orthogonal Polarization (CALIOP) and the Moderate Resolution Imaging Spectroradiometer (MODIS) for both cloud. Frey, S. Dutcher, R. E. Kuehn, M. A. Vaughan, and B. Baum (2008), Global Moderate Resolution Imaging

  10. Cloud Thickness and Satellite Images (title provided or enhanced by cataloger)

    NSDL National Science Digital Library

    Tom Whittaker

    This applet explores how the thickness of a cloud changes the way it looks from a satellite. The image is in the visible part of the spectrum, and the radiant energy is a function of not just temperature, as in the case of infrared images. The cloud thickness, its effective brightness, and the surface temperature can be modified while observing the satellite image.

  11. On the reduction of cloud influence in natural and aerial images

    Microsoft Academic Search

    T. B. Borchartt; R. H. C. de Melo; J. G. F. M. Gazolla; R. Resmini; A. Conci; A. Sanchez; E. de A. Vieira

    2011-01-01

    Due to global warming, an increase amount of water could be found in the environment. It causes the appearance of clouds in satellite and aerial image acquisitions. Clouds and shadows cause interference in aerial images acquired, that can be in two ways: signal attenuation and different range of illuminations. The signal attenuation is caused by the image acquisition above the

  12. Comparison of WRF Model Outputs and MODIS Image Products for Cloud Presence: A Case Study

    E-print Network

    Moelders, Nicole

    Comparison of WRF Model Outputs and MODIS Image Products for Cloud Presence: A Case Study REU to the MODIS satellite imaging cloud mask product. The images for March 13, 2008 were compared using ENVI and ESRI ArcGIS software packages at the accepted MODIS and WRF threshold values. A sensitivity analysis

  13. Statistical pattern recognition algorithms for autofluorescence imaging

    NASA Astrophysics Data System (ADS)

    Kulas, Zbigniew; Bere?-Pawlik, El?bieta; Wierzbicki, Jaros?aw

    2009-02-01

    In cancer diagnostics the most important problems are the early identification and estimation of the tumor growth and spread in order to determine the area to be operated. The aim of the work was to design of statistical algorithms helping doctors to objectively estimate pathologically changed areas and to assess the disease advancement. In the research, algorithms for classifying endoscopic autofluorescence images of larynx and intestine were used. The results show that the statistical pattern recognition offers new possibilities for endoscopic diagnostics and can be of a tremendous help in assessing the area of the pathological changes.

  14. Long-term prefetching for cloud medical imaging repositories.

    PubMed

    Viana-Ferreira, Carlos; Matos, Sérgio; Costa, Carlos

    2015-01-01

    Healthcare institutions have been outsourcing their IT infrastructure to the cloud. This new paradigm has financial and technological advantages. However, it has also associated some important issues. In the medical imaging field, studies typically involve high volumes of data, leading to increased communication latency in remote access environments. In this context, this paper presents a long-term prefetching solution that dynamically adapts itself to institutional workflows and services. Evaluation tests show that the proposed solution significantly reduces the data access latency. PMID:25991361

  15. Imaging Spatial Correlations of Rydberg Excitations in Cold Atom Clouds

    NASA Astrophysics Data System (ADS)

    Schwarzkopf, A.; Sapiro, R. E.; Raithel, G.

    2011-09-01

    We use direct spatial imaging of cold Rb85 Rydberg atom clouds to measure the Rydberg-Rydberg correlation function. The results are in qualitative agreement with theoretical predictions [F. Robicheaux and J. V. Hernández, Phys. Rev. A 72, 063403 (2005)PLRAAN1050-294710.1103/PhysRevA.72.063403]. We determine the blockade radius for states 44D5/2, 60D5/2, and 70D5/2 and investigate the dependence of the correlation behavior on excitation conditions and detection delay. Experimental data hint at the existence of long-range order.

  16. Clouds

    NSDL National Science Digital Library

    Carl Wozniak

    Clouds comprise a wonderful focus for classroom study. They're ubiquitous, ever-changing, scientifically interesting and, most importantly for teachers, they're cheap. The material presented here includes sections on cloud formation, cloud types, cloud pictures, other cloud-related phenomena, and a glossary.

  17. A Routing Mechanism for Cloud Outsourcing of Medical Imaging Repositories.

    PubMed

    Marques Godinho, Tiago; Viana-Ferreira, Carlos; Bastiao Silva, Luis; Costa, Carlos

    2014-10-16

    Web-based technologies have been increasingly used in Picture Archive and Communication Systems (PACS), in services related to storage, distribution and visualization of medical images. Nowadays, many healthcare institutions are outsourcing their repositories to the Cloud. However, managing communications between multiple geo-distributed locations is still challenging due to the complexity of dealing with huge volumes of data and bandwidth requirements. Moreover, standard methodologies still do not take full advantage of outsourced archives, namely because their integration with other in-house solutions is troublesome. In order to improve the performance of distributed medical imaging networks, a smart routing mechanism was developed. This includes an innovative cache system based on splitting and dynamic management of DICOM objects. The proposed solution was successfully deployed in a regional PACS archive. The results obtained proved that it is better than conventional approaches, as it reduces remote access latency and also the required cache storage space. PMID:25343773

  18. Medical image segmentation using object atlas versus object cloud models

    NASA Astrophysics Data System (ADS)

    Phellan, Renzo; Falcão, Alexandre X.; Udupa, Jayaram K.

    2015-03-01

    Medical image segmentation is crucial for quantitative organ analysis and surgical planning. Since interactive segmentation is not practical in a production-mode clinical setting, automatic methods based on 3D object appearance models have been proposed. Among them, approaches based on object atlas are the most actively investigated. A key drawback of these approaches is that they require a time-costly image registration process to build and deploy the atlas. Object cloud models (OCM) have been introduced to avoid registration, considerably speeding up the whole process, but they have not been compared to object atlas models (OAM). The present paper fills this gap by presenting a comparative analysis of the two approaches in the task of individually segmenting nine anatomical structures of the human body. Our results indicate that OCM achieve a statistically significant better accuracy for seven anatomical structures, in terms of Dice Similarity Coefficient and Average Symmetric Surface Distance.

  19. Congruence analysis of point clouds from unstable stereo image sequences

    NASA Astrophysics Data System (ADS)

    Jepping, C.; Bethmann, F.; Luhmann, T.

    2014-06-01

    This paper deals with the correction of exterior orientation parameters of stereo image sequences over deformed free-form surfaces without control points. Such imaging situation can occur, for example, during photogrammetric car crash test recordings where onboard high-speed stereo cameras are used to measure 3D surfaces. As a result of such measurements 3D point clouds of deformed surfaces are generated for a complete stereo sequence. The first objective of this research focusses on the development and investigation of methods for the detection of corresponding spatial and temporal tie points within the stereo image sequences (by stereo image matching and 3D point tracking) that are robust enough for a reliable handling of occlusions and other disturbances that may occur. The second objective of this research is the analysis of object deformations in order to detect stable areas (congruence analysis). For this purpose a RANSAC-based method for congruence analysis has been developed. This process is based on the sequential transformation of randomly selected point groups from one epoch to another by using a 3D similarity transformation. The paper gives a detailed description of the congruence analysis. The approach has been tested successfully on synthetic and real image data.

  20. Aerosol patterns and aerosol-cloud-interactions off the West African Coast based on the A-train formation

    NASA Astrophysics Data System (ADS)

    Fuchs, Julia; Bendix, Jörg; Cermak, Jan

    2013-04-01

    In this study, spatial and temporal aerosol patterns off the Western African coast are characterized and related to cloud properties, based on satellite data Atmospheric aerosols play a key role in atmospheric processes and influence our environmental system in a complex way. Their identification, characterization, transport patterns as well as their interactions with clouds pose major challenges. Especially the last aspect reveals major uncertainties in terms of the Earth's radiation budget as reported in the IPCC's Fourth Assessment Report (IPCC, 2007). Western and Southern Africa are dominated by two well-known source types of atmospheric aerosols. First, the Saharan Desert is the world's largest aeolian dust emitting source region. Second, biomass burning aerosol is commonly transported off-shore further south (Kaufman et al., 2005). Both aerosol types influence Earth's climate in different manners and can be detected by the MODIS (MODerate resolution Imaging Spectrometer) sensor onboard the EOS platforms as they propagate to the Central and Southern Atlantic. The motivation of this study was to reveal the seasonal pattern of the Saharan dust transport based on an observation period of 11 years and trying to explain the meteorological mechanisms. North African dust plumes are transported along a latitude of 19°N in July and 6°N in January. The seasonally fluctuating intensities adapt to the annual cycle of wind and precipitation regimes. A strong relationship is found between the spatial shift of the Azores High and the Saharan dust load over the middle Atlantic Ocean. Monthly Aerosol Optical Thickness products of Terra MODIS and NCEP-DOE (National Centers for Environmental Predictions) Reanalysis II data are used for this purpose. The relationship between aerosol and cloud droplet parameters is blurred by high sensitivities to aerosol size and composition (Feingold, 2003; McFiggans et al., 2006) as well as meteorological context (Ackerman et al., 2004). Satellite data from the A-train formation, including the Aqua, CloudSat and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) are used to analyze aerosol-cloud-interactions in detail, along with re-analysis data to constrain by meteorological conditions. Information about the vertical and geographical distribution of different aerosol types and cloud parameters will lead to a process-oriented understanding of these issues on a regional scale. Ackerman, A., Kirkpatrick, M., Stevens, D., & Toon, O. (2004). The impact of humidity above stratiform clouds on indirect aerosol climate forcing. Nature, 432(December), 1014-1017. doi:10.1038/nature03137.1. Feingold, G. (2003). First measurements of the Twomey indirect effect using ground-based remote sensors. Geophysical Research Letters, 30(6), 1287. doi:10.1029/2002GL016633 IPCC. (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working group I to the Fourth Assessment Report of the Interfovernmental Panel on climate Change. Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Kaufman, Y. J., Koren, I., Remer, L. A., Tanré, D., Ginoux, P., & Fan, S. (2005). Dust transport and deposition observed from the Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) spacecraft over the Atlantic Ocean. Journal of Geophysical Research, 110(D10), 1-16. doi:10.1029/2003JD004436 McFiggans, G., Artaxo, P., Baltensperger, U., Coe, H., Facchini, M. C., Feingold, G., Fuzzi, S., et al. (2006). The effect of physical and chemical aerosol properties on warm cloud droplet activation. Atmospheric Chemistry and Physics, 6(9), 2593-2649. doi:10.5194/acp-6-2593-2006

  1. Characterization of SEM speckle pattern marking and imaging distortion by Digital Image Correlation

    E-print Network

    via SEM imaging can be performed to provide spatially dense experimental 2D [3, 4], or even 3D [5, 6Characterization of SEM speckle pattern marking and imaging distortion by Digital Image Correlation patterning by e-beam lithography and SEM imaging distortions are studied via digital image correlation

  2. Searching for pulsars using image pattern recognition

    SciTech Connect

    Zhu, W. W.; Berndsen, A.; Madsen, E. C.; Tan, M.; Stairs, I. H. [Department of Physics and Astronomy, 6224 Agricultural Road, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Brazier, A. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Lazarus, P. [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Lynch, R.; Scholz, P. [Department of Physics, McGill University, Montreal, QC H3A 2T8 (Canada); Stovall, K.; Cohen, S.; Dartez, L. P.; Lunsford, G.; Martinez, J. G.; Mata, A. [Center for Advanced Radio Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States); Ransom, S. M. [NRAO, Charlottesville, VA 22903 (United States); Banaszak, S.; Biwer, C. M.; Flanigan, J.; Rohr, M., E-mail: zhuww@phas.ubc.ca, E-mail: berndsen@phas.ubc.ca [Center for Gravitation, Cosmology and Astrophysics. University of Wisconsin Milwaukee, Milwaukee, WI 53211 (United States); and others

    2014-02-01

    In the modern era of big data, many fields of astronomy are generating huge volumes of data, the analysis of which can sometimes be the limiting factor in research. Fortunately, computer scientists have developed powerful data-mining techniques that can be applied to various fields. In this paper, we present a novel artificial intelligence (AI) program that identifies pulsars from recent surveys by using image pattern recognition with deep neural nets—the PICS (Pulsar Image-based Classification System) AI. The AI mimics human experts and distinguishes pulsars from noise and interference by looking for patterns from candidate plots. Different from other pulsar selection programs that search for expected patterns, the PICS AI is taught the salient features of different pulsars from a set of human-labeled candidates through machine learning. The training candidates are collected from the Pulsar Arecibo L-band Feed Array (PALFA) survey. The information from each pulsar candidate is synthesized in four diagnostic plots, which consist of image data with up to thousands of pixels. The AI takes these data from each candidate as its input and uses thousands of such candidates to train its ?9000 neurons. The deep neural networks in this AI system grant it superior ability to recognize various types of pulsars as well as their harmonic signals. The trained AI's performance has been validated with a large set of candidates from a different pulsar survey, the Green Bank North Celestial Cap survey. In this completely independent test, the PICS ranked 264 out of 277 pulsar-related candidates, including all 56 previously known pulsars and 208 of their harmonics, in the top 961 (1%) of 90,008 test candidates, missing only 13 harmonics. The first non-pulsar candidate appears at rank 187, following 45 pulsars and 141 harmonics. In other words, 100% of the pulsars were ranked in the top 1% of all candidates, while 80% were ranked higher than any noise or interference. The performance of this system can be improved over time as more training data are accumulated. This AI system has been integrated into the PALFA survey pipeline and has discovered six new pulsars to date.

  3. Searching for Pulsars Using Image Pattern Recognition

    NASA Astrophysics Data System (ADS)

    Zhu, W. W.; Berndsen, A.; Madsen, E. C.; Tan, M.; Stairs, I. H.; Brazier, A.; Lazarus, P.; Lynch, R.; Scholz, P.; Stovall, K.; Ransom, S. M.; Banaszak, S.; Biwer, C. M.; Cohen, S.; Dartez, L. P.; Flanigan, J.; Lunsford, G.; Martinez, J. G.; Mata, A.; Rohr, M.; Walker, A.; Allen, B.; Bhat, N. D. R.; Bogdanov, S.; Camilo, F.; Chatterjee, S.; Cordes, J. M.; Crawford, F.; Deneva, J. S.; Desvignes, G.; Ferdman, R. D.; Freire, P. C. C.; Hessels, J. W. T.; Jenet, F. A.; Kaplan, D. L.; Kaspi, V. M.; Knispel, B.; Lee, K. J.; van Leeuwen, J.; Lyne, A. G.; McLaughlin, M. A.; Siemens, X.; Spitler, L. G.; Venkataraman, A.

    2014-02-01

    In the modern era of big data, many fields of astronomy are generating huge volumes of data, the analysis of which can sometimes be the limiting factor in research. Fortunately, computer scientists have developed powerful data-mining techniques that can be applied to various fields. In this paper, we present a novel artificial intelligence (AI) program that identifies pulsars from recent surveys by using image pattern recognition with deep neural nets—the PICS (Pulsar Image-based Classification System) AI. The AI mimics human experts and distinguishes pulsars from noise and interference by looking for patterns from candidate plots. Different from other pulsar selection programs that search for expected patterns, the PICS AI is taught the salient features of different pulsars from a set of human-labeled candidates through machine learning. The training candidates are collected from the Pulsar Arecibo L-band Feed Array (PALFA) survey. The information from each pulsar candidate is synthesized in four diagnostic plots, which consist of image data with up to thousands of pixels. The AI takes these data from each candidate as its input and uses thousands of such candidates to train its ~9000 neurons. The deep neural networks in this AI system grant it superior ability to recognize various types of pulsars as well as their harmonic signals. The trained AI's performance has been validated with a large set of candidates from a different pulsar survey, the Green Bank North Celestial Cap survey. In this completely independent test, the PICS ranked 264 out of 277 pulsar-related candidates, including all 56 previously known pulsars and 208 of their harmonics, in the top 961 (1%) of 90,008 test candidates, missing only 13 harmonics. The first non-pulsar candidate appears at rank 187, following 45 pulsars and 141 harmonics. In other words, 100% of the pulsars were ranked in the top 1% of all candidates, while 80% were ranked higher than any noise or interference. The performance of this system can be improved over time as more training data are accumulated. This AI system has been integrated into the PALFA survey pipeline and has discovered six new pulsars to date.

  4. Microwave Imager Measures Sea Surface Temperature Through Clouds

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image was acquired over Tropical Atlantic and U.S. East Coast regions on Aug. 22 - Sept. 23, 1998. Cloud data were collected by the Geostationary Operational Environmental Satellite (GOES). Sea Surface Temperature (SST) data were collected aboard the NASA/NASDA Tropical Rainfall Measuring Mission (TRMM) satellite by The TRMM Microwave Imager (TMI). TMI is the first satellite microwave sensor capable of accurately measuring sea surface temperature through clouds, as shown in this scene. For years scientists have known there is a strong correlation between sea surface temperature and the intensity of hurricanes. But one of the major stumbling blocks for forecasters has been the precise measurement of those temperatures when a storm begins to form. In this scene, clouds have been made translucent to allow an unobstructed view of the surface. Notice Hurricane Bonnie approaching the Carolina Coast (upper left) and Hurricane Danielle following roughly in its path (lower right). The ocean surface has been falsely colored to show a map of water temperature--dark blues are around 75oF, light blues are about 80oF, greens are about 85oF, and yellows are roughly 90oF. A hurricane gathers energy from warm waters found at tropical latitudes. In this image we see Hurricane Bonnie cross the Atlantic, leaving a cooler trail of water in its wake. As Hurricane Danielle followed in Bonnie's path, the wind speed of the second storm dropped markedly, as available energy to fuel the storm dropped off. But when Danielle left Bonnie's wake, wind speeds increased due to temperature increases in surface water around the storm. As a hurricane churns up the ocean, it's central vortex draws surface heat and water into the storm. That suction at the surface causes an upwelling of deep water. At depth, tropical ocean waters are significantly colder than water found near the surface. As they're pulled up to meet the storm, those colder waters essentially leave a footprint in the storm's wake which might last as long as two weeks. Forecasters can quantify the difference in surface temperatures between this footprint and the surrounding temperatures and use that information to better predict storm intensity. If another storm intersects with this cold water trail, it is likely to lose significant strength due to the fact that the colder water does not contain as much potential energy as warm water. TRMM Fact Sheet Predicting Hurricane Intensity Far from Land Remote Sensing Systems Image courtesy TRMM Project, Remote Sensing Systems, and Scientific Visualization Studio, NASA Goddard Space Flight Center

  5. Cloud masking in remotely sensed hyperspectral images using linear and nonlinear spectral mixture analysis

    E-print Network

    Plaza, Antonio J.

    The presence of clouds in satellite spectral images prevents adequate characterization of land coverCloud masking in remotely sensed hyperspectral images using linear and nonlinear spectral mixture (1) GPDS, Dept. of Electronic Eng., University of Valencia (Spain) (2) Dept. of Computer Science

  6. Astronomy In The Cloud: Using Mapreduce For Image Coaddition

    NASA Astrophysics Data System (ADS)

    Wiley, Keith; Connolly, A.; Gardner, J.; Krughoff, S.; Balazinska, M.; Howe, B.; Kwon, Y.; Bu, Y.

    2011-01-01

    In the coming decade, astronomical surveys of the sky will generate tens of terabytes of images and detect hundreds of millions of sources every night. The study of these sources will involve computational challenges such as anomaly detection, classification, and moving object tracking. Since such studies require the highest quality data, methods such as image coaddition, i.e., registration, stacking, and mosaicing, will be critical to scientific investigation. With a requirement that these images be analyzed on a nightly basis to identify moving sources, e.g., asteroids, or transient objects, e.g., supernovae, these datastreams present many computational challenges. Given the quantity of data involved, the computational load of these problems can only be addressed by distributing the workload over a large number of nodes. However, the high data throughput demanded by these applications may present scalability challenges for certain storage architectures. One scalable data-processing method that has emerged in recent years is MapReduce, and in this paper we focus on its popular open-source implementation called Hadoop. In the Hadoop framework, the data is partitioned among storage attached directly to worker nodes, and the processing workload is scheduled in parallel on the nodes that contain the required input data. A further motivation for using Hadoop is that it allows us to exploit cloud computing resources, i.e., platforms where Hadoop is offered as a service. We report on our experience implementing a scalable image-processing pipeline for the SDSS imaging database using Hadoop. This multi-terabyte imaging dataset provides a good testbed for algorithm development since its scope and structure approximate future surveys. First, we describe MapReduce and how we adapted image coaddition to the MapReduce framework. Then we describe a number of optimizations to our basic approach and report experimental results compring their performance. This work is funded by the NSF and by NASA.

  7. Venus: cloud level circulation during 1982 as determined from Pioneer cloud photopolarimeter images. 11. Solar longitude dependent circulation

    SciTech Connect

    Limaye, S.S.

    1988-02-01

    Pioneer Venus Orbiter images obtained in 1982 indicate a marked solar-locked dependence of cloud level circulation in both averaged cloud motions and cloud layer UV reflectivity. An apparent relationship is noted between horizontal divergence and UV reflectivity: the highest reflectivities are associated with regions of convergence at high latitudes, while lower values are associated with equatorial latitude regions where the motions are divergent. In solar-locked coordinates, the rms deviation of normalized UV brightness is higher at 45-deg latitudes than in equatorial regions. 37 references.

  8. High-resolution (375 m) cloud microstructure as seen from the NPP/VIIRS satellite imager

    NASA Astrophysics Data System (ADS)

    Rosenfeld, D.; Liu, G.; Yu, X.; Zhu, Y.; Dai, J.; Xu, X.; Yue, Z.

    2014-03-01

    VIIRS (Visible Infrared Imaging Radiometer Suite), onboard the Suomi NPP (National Polar-orbiting Partnership) satellite, has an improved resolution of 750 m with respect to the 1000 m of the Moderate Resolution Imaging Spectroradiometer for the channels that allow retrieving cloud microphysical parameters such as cloud drop effective radius (re). VIIRS also has an imager with five channels of double resolution of 375 m, which was not designed for retrieving cloud products. A methodology for a high-resolution retrieval of re and microphysical presentation of the cloud field based on the VIIRS imager was developed and evaluated with respect to MODIS in this study. The tripled microphysical resolution with respect to MODIS allows obtaining new insights for cloud-aerosol interactions, especially at the smallest cloud scales, because the VIIRS imager can resolve the small convective elements that are sub-pixel for MODIS cloud products. Examples are given for new insights into ship tracks in marine stratocumulus, pollution tracks from point and diffused sources in stratocumulus and cumulus clouds over land, deep tropical convection in pristine air mass over ocean and land, tropical clouds that develop in smoke from forest fires and in heavy pollution haze over densely populated regions in southeastern Asia, and for pyro-cumulonimbus clouds. It is found that the VIIRS imager provides more robust physical interpretation and refined information for cloud and aerosol microphysics as compared to MODIS, especially in the initial stage of cloud formation. VIIRS is found to identify significantly more fully cloudy pixels when small boundary layer convective elements are present. This, in turn, allows for a better quantification of cloud-aerosol interactions and impacts on precipitation-forming processes.

  9. High resolution (375 m) cloud microstructure as seen from the NPP/VIIRS Satellite imager

    NASA Astrophysics Data System (ADS)

    Rosenfeld, D.; Liu, G.; Yu, X.; Zhu, Y.; Dai, J.; Xu, X.; Yue, Z.

    2013-11-01

    The VIIRS (Visible Infrared Imaging Radiometer Suite) onboard the Suomi NPP (National Polar-Orbiting Partnership) satellite has improved resolution of 750 m with respect to 1000 m of the MODerate-resolution Imaging Spectroradiometer, for the channels that allow retrieving cloud microphysical parameters such as cloud drop effective radius (re). The VIIRS has also an imager with 5 channels of double resolution of 375 m, which was not designed for retrieving cloud products. A methodology for a high resolution retrieval of re and microphysical presentation of the cloud field based on the VIIRS imager was developed and evaluated with respect to MODIS in this study. The tripled microphysical resolution with respect to MODIS allows obtaining new insights for cloud aerosol interactions, especially at the smallest cloud scales, because the VIIRS imager can resolve the small convective elements that are sub-pixel for MODIS cloud products. Examples are given for new insights on ship tracks in marine stratocumulus, pollution tracks from point and diffused sources in stratocumulus and cumulus clouds over land, deep tropical convection in pristine air mass over ocean and land, tropical clouds that develop in smoke from forest fires and in heavy pollution haze over densely populated regions in southeast Asia, and for pyro-cumulonimbus clouds. It is found that the VIIRS imager provides more robust physical interpretation and refined information for cloud and aerosol microphysics as compared to MODIS, especially in the initial stage of cloud formation. VIIRS is found to identify much more full-cloudy pixels when small boundary layer convective elements are present. This, in turn, allows a better quantification of cloud aerosol interactions and impacts on precipitation forming processes.

  10. Analysis of Point Cloud Generation from UAS Images

    NASA Astrophysics Data System (ADS)

    Ostrowski, S.; Jó?ków, G.; Toth, C.; Vander Jagt, B.

    2014-11-01

    Unmanned Aerial Systems (UAS) allow for the collection of low altitude aerial images, along with other geospatial information from a variety of companion sensors. The images can then be processed using sophisticated algorithms from the Computer Vision (CV) field, guided by the traditional and established procedures from photogrammetry. Based on highly overlapped images, new software packages which were specifically developed for UAS technology can easily create ground models, such as Point Clouds (PC), Digital Surface Model (DSM), orthoimages, etc. The goal of this study is to compare the performance of three different software packages, focusing on the accuracy of the 3D products they produce. Using a Nikon D800 camera installed on an ocotocopter UAS platform, images were collected during subsequent field tests conducted over the Olentangy River, north from the Ohio State University campus. Two areas around bike bridges on the Olentangy River Trail were selected because of the challenge the packages would have in creating accurate products; matching pixels over the river and dense canopy on the shore presents difficult scenarios to model. Ground Control Points (GCP) were gathered at each site to tie the models to a local coordinate system and help assess the absolute accuracy for each package. In addition, the models were also relatively compared to each other using their PCs.

  11. How consistent are precipitation patterns predicted by GCMs in the absence of cloud radiative effects?

    NASA Astrophysics Data System (ADS)

    Popke, Dagmar; Bony, Sandrine; Mauritsen, Thorsten; Stevens, Bjorn

    2015-04-01

    Model simulations with state-of-the-art general circulation models reveal a strong disagreement concerning the simulated regional precipitation patterns and their changes with warming. The deviating precipitation response even persists when reducing the model experiment complexity to aquaplanet simulation with forced sea surface temperatures (Stevens and Bony, 2013). To assess feedbacks between clouds and radiation on precipitation responses we analyze data from 5 models performing the aquaplanet simulations of the Clouds On Off Klima Intercomparison Experiment (COOKIE), where the interaction of clouds and radiation is inhibited. Although cloud radiative effects are then disabled, the precipitation patterns among models are as diverse as with cloud radiative effects switched on. Disentangling differing model responses in such simplified experiments thus appears to be key to better understanding the simulated regional precipitation in more standard configurations. By analyzing the local moisture and moist static energy budgets in the COOKIE experiments we investigate likely causes for the disagreement among models. References Stevens, B. & S. Bony: What Are Climate Models Missing?, Science, 2013, 340, 1053-1054

  12. Investigation of vortex clouds and droplet sizes in heated water spray patterns generated by axisymmetric full cone nozzles.

    PubMed

    Naz, M Y; Sulaiman, S A; Ariwahjoedi, B; Ku Shaari, Ku Zilati

    2013-01-01

    The hot water sprays are an important part of many industrial processes, where the detailed knowledge of physical phenomena involved in jet transportation, interaction, secondary breakup, evaporation, and coalescence of droplets is important to reach more efficient processes. The objective of the work was to study the water spray jet breakup dynamics, vortex cloud formation, and droplet size distribution under varying temperature and load pressure. Using a high speed camera, the spray patterns generated by axisymmetric full cone nozzles were visualized as a function water temperature and load pressure. The image analysis confirmed that the spray cone angle and width do not vary significantly with increasing Reynolds and Weber numbers at early injection phases leading to increased macroscopic spray propagation. The formation and decay of semitorus like vortex clouds were also noticed in spray structures generated at near water boiling point temperature. For the nozzle with smallest orifice diameter (1.19 mm), these vortex clouds were very clear at 90°C heating temperature and 1 bar water load pressure. In addition, the sauter mean diameter (SMD) of the spray droplets was also measured by using Phase Doppler Anemometry (PDA) at different locations downstream of the nozzle exit. It was noticed that SMD varies slightly w.r.t. position when measured at room temperature whereas at higher temperature values, it became almost constant at distance of 55 mm downstream of the nozzle exit. PMID:24307881

  13. Investigation of Vortex Clouds and Droplet Sizes in Heated Water Spray Patterns Generated by Axisymmetric Full Cone Nozzles

    PubMed Central

    Naz, M. Y.; Sulaiman, S. A.; Ariwahjoedi, B.; Ku Shaari, Ku Zilati

    2013-01-01

    The hot water sprays are an important part of many industrial processes, where the detailed knowledge of physical phenomena involved in jet transportation, interaction, secondary breakup, evaporation, and coalescence of droplets is important to reach more efficient processes. The objective of the work was to study the water spray jet breakup dynamics, vortex cloud formation, and droplet size distribution under varying temperature and load pressure. Using a high speed camera, the spray patterns generated by axisymmetric full cone nozzles were visualized as a function water temperature and load pressure. The image analysis confirmed that the spray cone angle and width do not vary significantly with increasing Reynolds and Weber numbers at early injection phases leading to increased macroscopic spray propagation. The formation and decay of semitorus like vortex clouds were also noticed in spray structures generated at near water boiling point temperature. For the nozzle with smallest orifice diameter (1.19?mm), these vortex clouds were very clear at 90°C heating temperature and 1 bar water load pressure. In addition, the sauter mean diameter (SMD) of the spray droplets was also measured by using Phase Doppler Anemometry (PDA) at different locations downstream of the nozzle exit. It was noticed that SMD varies slightly w.r.t. position when measured at room temperature whereas at higher temperature values, it became almost constant at distance of 55?mm downstream of the nozzle exit. PMID:24307881

  14. A Cloud-Tracking Tool For Planetary Orbiter Images

    NASA Astrophysics Data System (ADS)

    Gil, R.; Luz, D.; Berry, D.; Roos-Serote, M.

    2005-08-01

    During their operations phase, planetary missions continuously produce a wealth of data that tend to overwhelm research teams. Spectral imagers, in particular, produce data cubes in which the wavelength dimension adds to the two spatial dimensions. Tracking of atmospheric features in order to derive winds and the construction of global maps from such large data volumes becomes particularly time-consuming if done manually. This highlights the importance of automated procedures capable of analysing sequences of data cubes with minimal user interaction. A tool for cloud tracking for such a purpose is currently under development in our group. In its present state it is based on synthetic images and uses a simple method of multiple matrix comparison to derive wind components. Deriving winds from data from the Venus Express - Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS) instrument will be a possible application. We shall present an overview of the method, its benchmarking and the current status and future development of the project. [R. Gil is currently supported by Fundacao para a Ciencia e a Tecnologia, Portugal, project PDCTU/FNU/49822/2003. D. Luz acknowledges support from FCT, grant SFRH-BPD-3630-2000.

  15. Cloud top structure of Venus revealed by Subaru/COMICS mid-infrared images

    NASA Astrophysics Data System (ADS)

    Sato, T. M.; Sagawa, H.; Kouyama, T.; Mitsuyama, K.; Satoh, T.; Ohtsuki, S.; Ueno, M.; Kasaba, Y.; Nakamura, M.; Imamura, T.

    2014-11-01

    We have investigated the cloud top structure of Venus by analyzing ground-based images taken at the mid-infrared wavelengths of 8.66 ?m and 11.34 ?m. Venus at a solar phase angle of ?90°, with the morning terminator in view, was observed by the Cooled Mid-Infrared Camera and Spectrometer (COMICS), mounted on the 8.2-m Subaru Telescope, during the period October 25-29, 2007. The disk-averaged brightness temperatures for the observation period are ?230 K and ?238 K at 8.66 ?m and 11.34 ?m, respectively. The obtained images with good signal-to-noise ratio and with high spatial resolution (?200 km at the sub-observer point) provide several important findings. First, we present observational evidence, for the first time, of the possibility that the westward rotation of the polar features (the hot polar spots and the surrounding cold collars) is synchronized between the northern and southern hemispheres. Second, after high-pass filtering, the images reveal that streaks and mottled and patchy patterns are distributed over the entire disk, with typical amplitudes of ?0.5 K, and vary from day to day. The detected features, some of which are similar to those seen in past UV images, result from inhomogeneities of both the temperature and the cloud top altitude. Third, the equatorial center-to-limb variations of brightness temperatures have a systematic day-night asymmetry, except those on October 25, that the dayside brightness temperatures are higher than the nightside brightness temperatures by 0-4 K under the same viewing geometry. Such asymmetry would be caused by the propagation of the migrating semidiurnal tide. Finally, by applying the lapse rates deduced from previous studies, we demonstrate that the equatorial center-to-limb curves in the two spectral channels give access to two parameters: the cloud scale height H and the cloud top altitude zc. The acceptable models for data on October 25 are obtained at H = 2.4-4.3 km and zc = 66-69 km; this supports previous results determined from spacecraft observations.

  16. Quantitative Comparison of Dense Cloud Detection of an Evolutionary Image Classification Algorithm to the MODIS Cloud Mask and to the VIIRS Cloud Mask

    NASA Astrophysics Data System (ADS)

    Momm, H. G.; Easson, G.

    2006-12-01

    The proper identification of cloud cover plays an important role for the accurate determination of atmospheric and surface parameters from remotely sensed data. The MODIS (Moderate Resolution Imaging Spectroradiometer) cloud mask algorithm has been used by NASA and other governmental agencies as input for models, analysis systems, and decision support tools. The Visible Infrared Imager Radiometer Suite (VIIRS) cloud mask will be an important product for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) and it has been researched as a replacement alternative in many of the existing NASA programs. Among them, the Rapid Prototyping Capability (RPC) project, at the University of Mississippi, investigates the VIIRS data as a replacement for the MODIS data in the SERVIR Decision Support Tool, which uses cloud masks as required inputs. In this project, the performance of these algorithms is compared to the Evolutionary Image Classification Algorithm (EICA). This semi-automated learn-from- examples evolutionary framework was used for dense cloud detection by combining preprocessing functions with standard unsupervised classification algorithms. The preprocessing functions as well as the parameters used in the unsupervised classification step were defined by genetic programming as the evolutionary tool to search for the optimal solution. Genetic programming evolves (iterative trial and error process) preprocessing functions formed by spectral indices built from basic function blocks defined in the function set (arithmetic operations) and in the terminal set (spectral bands). MODIS granules covering Central America were selected at different dates during the fire season to be used as the study site. These granules were manually classified using the first two MODIS channels and were considered as reference data. The cloud mask generated from the evolutionary classification algorithm, the VIIRS cloud mask and the MODIS cloud mask results were then compared using the Kappa statistics as the measurement of success.

  17. Characterization of gravity waves at Venus cloud top from the Venus Monitoring Camera images

    NASA Astrophysics Data System (ADS)

    Piccialli, A.; Titov, D.; Svedhem, H.; Markiewicz, W. J.

    2012-04-01

    Since 2006 the European mission Venus Express (VEx) is studying Venus atmosphere with a focus on atmospheric dynamics and circulation. Recently, several experiments on board Venus Express have detected waves in the Venus atmosphere both as oscillations in the temperature and wind fields and as patterns on the cloud layer. Waves could be playing an important role in the maintenance of the atmospheric circulation of Venus since they can transport energy and momentum. High resolution images of Venus Northern hemisphere obtained with the Venus Monitoring Camera (VMC/VEx) show distinct wave patterns at the cloud tops (~70 km altitude) interpreted as gravity waves. Venus Monitoring Camera (VMC) is a CCD-based camera specifically designed to take images of Venus in four narrow band filters in UV (365 nm), visible (513 nm), and near-IR (965 and 1000 nm). A systematic visual search of waves in VMC images was performed; more than 1700 orbits were analyzed and wave patterns were observed in about 200 images. With the aim to characterize the wave types and their possible origin, we retrieved wave properties such as location (latitude and longitude), local time, solar zenith angle, packet length and width, and orientation. A wavelet analysis was also applied to determine the wavelength and the region of dominance of each wave. Four types of waves were identified in VMC images: long, medium, short and irregular waves. The long type waves are characterized by long and narrow straight features extending more than a few hundreds kilometers and with a wavelength within the range of 7 to 48 km. Medium type waves have irregular wavefronts extending more than 100 km and with wavelengths in the range 8 - 21 km. Short wave packets have a width of several tens of kilometers and extends to few hundreds kilometers and are characterized by small wavelengths (3 - 16 km). Often short waves trains are observed at the edges of long features and seem connected to them. Irregular wave fields extend beyond the field of view of VMC and appear to be the result of wave breaking or wave interference. The waves are often identified in all channels and are mostly found at high latitudes (60-80°N) in the Northern hemisphere and seem to be concentrated above Ishtar Terra, a continental size highland that includes the highest mountain belts of the planet, thus suggesting a possible orographic origin of the waves. However, at the moment it is not possible to rule out a bias in the observations due to the spacecraft orbit that prevents waves to be seen at lower latitudes, because of lower resolution, and on the night side of the planet.

  18. 3D cloud detection and tracking system for solar forecast using multiple sky imagers

    DOE PAGESBeta

    Peng, Zhenzhou; Yu, Dantong; Huang, Dong; Heiser, John; Yoo, Shinjae; Kalb, Paul

    2015-08-01

    We propose a system for forecasting short-term solar irradiance based on multiple total sky imagers (TSIs). The system utilizes a novel method of identifying and tracking clouds in three-dimensional space and an innovative pipeline for forecasting surface solar irradiance based on the image features of clouds. First, we develop a supervised classifier to detect clouds at the pixel level and output cloud mask. In the next step, we design intelligent algorithms to estimate the block-wise base height and motion of each cloud layer based on images from multiple TSIs. This information is then applied to stitch images together into largermore »views, which are then used for solar forecasting. We examine the system’s ability to track clouds under various cloud conditions and investigate different irradiance forecast models at various sites. We confirm that this system can 1) robustly detect clouds and track layers, and 2) extract the significant global and local features for obtaining stable irradiance forecasts with short forecast horizons from the obtained images. Finally, we vet our forecasting system at the 32-megawatt Long Island Solar Farm (LISF). Compared with the persistent model, our system achieves at least a 26% improvement for all irradiance forecasts between one and fifteen minutes.« less

  19. Characterization of aerosol-containing chemical simulant clouds using a sensitive, thermal infrared imaging spectrometer

    Microsoft Academic Search

    Jeffrey L. Hall; Francis M. D'Amico; Steven J. Kolodzey; Jun Qian; Mark L. Polak; Karl Westerberg; Clement S. Chang

    2011-01-01

    A sensitive, ground-based thermal imaging spectrometer was deployed at the Army's Dugway Proving Ground to remotely monitor explosively released chemical-warfare-agent-simulant clouds from stand-off ranges of a few kilometers. The sensor has 128 spectral bands covering the 7.6 to 13.5 micron region. The measured cloud spectra clearly showed scattering of high-elevation-angle sky radiance by liquid aerosols or dust in the clouds:

  20. Clouds

    NSDL National Science Digital Library

    Ms. Doxey

    2010-03-26

    Students learn about the varieties of clouds, what they look like and how they can affect our lives. Introduction: Have you ever wondered what kind of cloud makes rain, or which one makes fog? Have you ever wondered if there are clouds that mean the weather if going to be good or not? Today, we're going to learn about three different clouds that may ...

  1. Accuracy assessment of building point clouds automatically generated from iphone images

    NASA Astrophysics Data System (ADS)

    Sirmacek, B.; Lindenbergh, R.

    2014-06-01

    Low-cost sensor generated 3D models can be useful for quick 3D urban model updating, yet the quality of the models is questionable. In this article, we evaluate the reliability of an automatic point cloud generation method using multi-view iPhone images or an iPhone video file as an input. We register such automatically generated point cloud on a TLS point cloud of the same object to discuss accuracy, advantages and limitations of the iPhone generated point clouds. For the chosen example showcase, we have classified 1.23% of the iPhone point cloud points as outliers, and calculated the mean of the point to point distances to the TLS point cloud as 0.11 m. Since a TLS point cloud might also include measurement errors and noise, we computed local noise values for the point clouds from both sources. Mean (?) and standard deviation (?) of roughness histograms are calculated as (?1 = 0.44 m., ?1 = 0.071 m.) and (?2 = 0.025 m., ?2 = 0.037 m.) for the iPhone and TLS point clouds respectively. Our experimental results indicate possible usage of the proposed automatic 3D model generation framework for 3D urban map updating, fusion and detail enhancing, quick and real-time change detection purposes. However, further insights should be obtained first on the circumstances that are needed to guarantee a successful point cloud generation from smartphone images.

  2. Direct image reconstruction from a Fourier intensity pattern using HERALDO

    E-print Network

    Fienup, James R.

    in the development of coherent lensless imaging tech- niques. Holography with extended reference by auto- correlationDirect image reconstruction from a Fourier intensity pattern using HERALDO Manuel Guizar believe to be the first experimental demonstration of a novel coherent lensless imaging technique

  3. Skeletal Structures in the Images of Cosmic Dust Clouds and Solar System Planets

    Microsoft Academic Search

    Valentin A. Rantsev-Kartinov

    2007-01-01

    Multilevel dynamical contrasting of cosmic dust cloud images reveals the presence of skeletallike structures that are similar to those found in various electrical discharges and in space plasmas. These results, which are concentric cylinders in interstellar space, corroborate the discovery of interstellar neutral hydrogen (HI) emission spectra that are recorded in radio astronomy from low- and high-velocity intergalactic clouds in

  4. Active Cloud Probing with Los Alamos National Laboratory's Wide Angle Imaging Lidar: Status and Outlook

    Microsoft Academic Search

    I. N. Polonsky; A. B. Davis; S. P. Brumby

    Summary We survey recent developments in off-beam cloud lidar and especially the Wide Angle Imaging Lidar (WAIL) developed at Los Alamos National Laboratory (LANL). By abandoning the single back- scattering assumption of standard (on-beam) lidar in favor of a multiple scattering model and with the appropriate modifications of the instrument, we enable detection robust detection of the cloud boundary opposite

  5. Patterns of satellite-viewed, subtropical, jet-stream clouds in relation to the observed wind field 

    E-print Network

    Vogt, Richard Joel

    1972-01-01

    PATTERNS OF SATELLITE-VIEWED, SUBTROPICAL, JET- STREAM CLOUDS IN RELATION TO THE OBSERVED WIND FIELD A Thesis by RICHARD JOEL VOGT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE December 1972 Major Subject: Meteorology PATTERNS OP SATELLITE-VIEWED, SUBTROPICAL, JET-STREAM CLOUDS IN RELATION TO THE OBSERVED WIND FIELD A Thesis by RICHARD JOEL VOGT Approved as to style and content by: (Chairman...

  6. Pattern Recognition Software and Techniques for Biological Image Analysis

    PubMed Central

    Shamir, Lior; Delaney, John D.; Orlov, Nikita; Eckley, D. Mark; Goldberg, Ilya G.

    2010-01-01

    The increasing prevalence of automated image acquisition systems is enabling new types of microscopy experiments that generate large image datasets. However, there is a perceived lack of robust image analysis systems required to process these diverse datasets. Most automated image analysis systems are tailored for specific types of microscopy, contrast methods, probes, and even cell types. This imposes significant constraints on experimental design, limiting their application to the narrow set of imaging methods for which they were designed. One of the approaches to address these limitations is pattern recognition, which was originally developed for remote sensing, and is increasingly being applied to the biology domain. This approach relies on training a computer to recognize patterns in images rather than developing algorithms or tuning parameters for specific image processing tasks. The generality of this approach promises to enable data mining in extensive image repositories, and provide objective and quantitative imaging assays for routine use. Here, we provide a brief overview of the technologies behind pattern recognition and its use in computer vision for biological and biomedical imaging. We list available software tools that can be used by biologists and suggest practical experimental considerations to make the best use of pattern recognition techniques for imaging assays. PMID:21124870

  7. Thermal ghost imaging with averaged speckle patterns

    E-print Network

    Shapiro, Jeffrey H.

    We present theoretical and experimental results showing that a thermal ghost imaging system can produce images of high quality even when it uses detectors so slow that they respond only to intensity-averaged (that is, ...

  8. Watershed identification of polygonal patterns in noisy SAR images.

    PubMed

    Moreels, Pierre; Smrekar, Suzanne E

    2003-01-01

    This paper describes a new approach to pattern recognition in synthetic aperture radar (SAR) images. A visual analysis of the images provided by NASA's Magellan mission to Venus has revealed a number of zones showing polygonal-shaped faults on the surface of the planet. The goal of the paper is to provide a method to automate the identification of such zones. The high level of noise in SAR images and its multiplicative nature make automated image analysis difficult and conventional edge detectors, like those based on gradient images, inefficient. We present a scheme based on an improved watershed algorithm and a two-scale analysis. The method extracts potential edges in the SAR image, analyzes the patterns obtained, and decides whether or not the image contains a "polygon area". This scheme can also be applied to other SAR or visual images, for instance in observation of Mars and Jupiter's satellite Europa. PMID:18237949

  9. A novel computer-generated hologram (CGH) achieved scheme using point cloud based on integral imaging

    NASA Astrophysics Data System (ADS)

    Li, Wei-Na; Piao, Mei-Lan; Jeon, Seok-Hee; Jeong, Jong-Rae; Kim, Nam

    2015-03-01

    We proposed a novel scheme to achieve a computer-generated hologram (CGH). The CGH is generated from a point cloud that is transformed by a mapping relationship of a series of sub-images. The sub-images are converted from elemental images captured by integral imaging pickup system. A more continues depth map can be obtained and a clearer display of the 3D scene can be presented. Moreover, the inherent drawback pseudoscopic problem of integral imaging can also be overcome.

  10. Efficient dictionary design for multiscale recurrent pattern image coding

    Microsoft Academic Search

    Nuno M. M. Rodrigues; Eduardo A. B. Da Silva; Murilo B. De Carvalho; Sérgio M. M. De Faria; Vítor Manuel Mendes Da Silva; F. Pinage

    2006-01-01

    Abstractó MMP-Intra was recently proposed as a recurrent patterns based image encoder that combines the Multidimen- sional Multiscale Parser (MMP) algorithm with intra prediction techniques. Our results show that this method is able to achieve considerable gains over state-of-the-art transform-based image encoders for a wide variety of types of images, like text, composed (text and graphics) and texture images, while

  11. Improving Multiscale Recurrent Pattern Image Coding With Deblocking Filtering

    Microsoft Academic Search

    Nuno M. M. Rodrigues; Eduardo A. B. Da Silva; Murilo B. De Carvalho; Sérgio M. M. De Faria; Vítor Manuel Mendes Da Silva

    2006-01-01

    The Multidimensional Multiscale Parser (MMP) algorithm is an image encoder that approximates the image blocks by using recurrent\\u000a patterns, from an adaptive dictionary, at different scales. This encoder performs well for a large range of image data. However,\\u000a images encoded with MMP suffer from blocking artifacts. This paper presents the design of a deblocking filter that improves\\u000a the performance the

  12. Structure and Semi-Fluid Motion Analysis of Stereoscopic Satellite Images for Cloud Tracking

    Microsoft Academic Search

    Kannappan Palaniappan; Chandra Kambhamettu; Frederick Hasler; Dmitry B. GoldgofS

    1995-01-01

    Time-varying multispectral observations of cloudsfrom meteorological satellites are used to estimatecloud-top heights (structure) and cloud winds (semifluidmotion). Stereo image pairs over several timesteps were acquired by two geostationary satellites withsynchronized scanning instruments. Cloud-top heightestimation from these image pairs is performed usingan improved automatic stereo analysis algorithm on amassively parallel Maspar computer with 16K processors.A new category of...

  13. Registration of vehicle based panoramic image and LiDAR point cloud

    NASA Astrophysics Data System (ADS)

    Chen, Changjun; Cao, Liang; Xie, Hong; Zhuo, Xiangyu

    2013-10-01

    Higher quality surface information would be got when data from optical images and LiDAR were integrated, owing to the fact that optical images and LiDAR point cloud have unique characteristics that make them preferable in many applications. While most previous works focus on registration of pinhole perspective cameras to 2D or 3D LiDAR data. In this paper, a method for the registration of vehicle based panoramic image and LiDAR point cloud is proposed. Using the translation among panoramic image, single CCD image, laser scanner and Position and Orientation System (POS) along with the GPS/IMU data, precise co-registration between the panoramic image and the LiDAR point cloud in the world system is achieved. Results are presented under a real world data set collected by a new developed Mobile Mapping System (MMS) integrated with a high resolution panoramic camera, two laser scanners and a POS.

  14. A novel approach for the extraction of cloud motion vectors using airglow imager measurements

    NASA Astrophysics Data System (ADS)

    Satheesh Kumar, S.; Narayana Rao, T.; Taori, A.

    2015-03-01

    The paper explores the possibility of implementing an advanced photogrammetric technique, generally employed for satellite measurements, on airglow imager, a ground-based remote sensing instrument primarily used for upper atmospheric studies, measurements of clouds for the extraction of cloud motion vectors (CMVs). The major steps involved in the algorithm remain the same, including image processing for better visualization of target elements and noise removal, identification of target cloud, setting a proper search window for target cloud tracking, estimation of cloud height, and employing 2-D cross-correlation to estimate the CMVs. Nevertheless, the implementation strategy at each step differs from that of satellite, mainly to suit airglow imager measurements. For instance, climatology of horizontal winds at the measured site has been used to fix the search window for target cloud tracking. The cloud height is estimated very accurately, as required by the algorithm, using simultaneous collocated Lidar measurements. High-resolution, both in space and time (4 min), cloud imageries are employed to minimize the errors in retrieved CMVs. The derived winds are evaluated against MST radar-derived winds by considering it as a reference. A very good correspondence is seen between these two wind measurements, both showing similar wind variation. The agreement is also found to be good in the both zonal and meridional wind velocities with RMSEs < 2.4 m s-1. At the end, the strengths and limitations of the algorithm are discussed, with possible solutions, wherever required.

  15. Classification of storms based on their boundaries and cloud top temperatures using satellite imagery

    Microsoft Academic Search

    Baolie Cheng; J. Fernando Vega-Riveros; Kamal Jabbour; Walter Meyer

    1989-01-01

    A system for interpreting and classifying severe weather patterns is presented. The system uses several image-processing and pattern-recognition techniques to detect storms in satellite cloud cover imagery. It performs several basic satellite image-interpretation tasks, i.e. cloud boundary detection, cloud top temperature and height estimation, cloud systems motion analysis, and storm classification. Some preliminary results on actual satellite images are presented

  16. Identification of damage in buildings based on gaps in 3D point clouds from very high resolution oblique airborne images

    NASA Astrophysics Data System (ADS)

    Vetrivel, Anand; Gerke, Markus; Kerle, Norman; Vosselman, George

    2015-07-01

    Point clouds generated from airborne oblique images have become a suitable source for detailed building damage assessment after a disaster event, since they provide the essential geometric and radiometric features of both roof and façades of the building. However, they often contain gaps that result either from physical damage or from a range of image artefacts or data acquisition conditions. A clear understanding of those reasons, and accurate classification of gap-type, are critical for 3D geometry-based damage assessment. In this study, a methodology was developed to delineate buildings from a point cloud and classify the present gaps. The building delineation process was carried out by identifying and merging the roof segments of single buildings from the pre-segmented 3D point cloud. This approach detected 96% of the buildings from a point cloud generated using airborne oblique images. The gap detection and classification methods were tested using two other data sets obtained with Unmanned Aerial Vehicle (UAV) images with a ground resolution of around 1-2 cm. The methods detected all significant gaps and correctly identified the gaps due to damage. The gaps due to damage were identified based on the surrounding damage pattern, applying Gabor wavelets and a histogram of gradient orientation features. Two learning algorithms - SVM and Random Forests were tested for mapping the damaged regions based on radiometric descriptors. The learning model based on Gabor features with Random Forests performed best, identifying 95% of the damaged regions. The generalization performance of the supervised model, however, was less successful: quality measures decreased by around 15-30%.

  17. Cloud screening Coastal Zone Color Scanner images using channel 5

    Microsoft Academic Search

    B. A. Eckstein; J. J. Simpson

    1991-01-01

    Clouds are removed from Coastal Zone Color Scanner (CZCS) data using channel 5. Instrumentation problems require pre-processing of channel 5 before an intelligent cloud-screening algorithm can be used. For example, at intervals of about 16 lines, the sensor records anomalously low radiances. Moreover, the calibration equation yields negative radiances when the sensor records zero counts, and pixels corrupted by electronic

  18. "Advances" in Cloud Imager Remote Sensing Andrew Heidinger

    E-print Network

    Kuligowski, Bob

    as the visible/near-infrared/infrared multi-channel satellite instruments such as AVHRR, MODIS, VIIRS, ABI Cloud Algorithm Test-bed. Similar functionality to GEOCAT but designed for MODIS. Developed under a IPO for navigation errors ·Climate consistency (AVHRR/MODIS) · Remaining Issues in Cloud Remote Sensing. #12

  19. PATTERN MATCHING IMAGE COMPRESSION: Algorithmic and Empirical Results

    E-print Network

    Szpankowski, Wojciech

    [32] and LZ78 [33] -- is very attractive for text compression. For example, such schemes were used scheme based on approximate pattern matching, that we name Pattern Matching Image Compression (PMIC). The main idea behind it is a lossy extension of the Lempel­Ziv data compression scheme in which one

  20. Signal filtering of daily cloud types' trends as derived from satellite images

    NASA Astrophysics Data System (ADS)

    Dim, Jules R.; Murakami, Hiroshi

    2011-03-01

    The relationship between the intensity functions of contiguous pixels of an image is used on daily global clouds satellite data to extract local edge gradients for cloud types' classification. The images are cloud top temperatures (CTT) derived from the National Oceanic and Atmospheric Administration/Advanced Very-High-Resolution Radiometer (NOAA-AVHRR) satellite observations. The cloud type classification method used is a histogram-based gradient scheme described as the occurrence of low, mid or high edge gradients in a block of pixels. The distribution of these cloud types is analyzed, then, the consistency of the monthly variations of the cloud type amount estimation is evaluated. A clear dependence of the cloud type amount signal on the solar zenith angle is noticeable. This dependence, due to the gradual satellite drift, is removed through a filtering process using the empirical mode decomposition (EMD) method. The EMD component, associated with the drift or the solar zenith angle change, is filtered out. The cloud types' amount series corrected show a substantial improvement in their trends.

  1. Current Status of Cloud Masks for the Multi-angle Imaging SpectroRadiometer

    NASA Astrophysics Data System (ADS)

    Wilson, M. J.; Zhao, G.; Yang, Y.; Chapman, B.; di Girolamo, L.

    2004-05-01

    The Multi-angle Imaging SpectroRadiometer (MISR) on-board EOS-Terra makes observations at 9 angles (1 nadir, 8 oblique) in the visible and near-infrared. Cloud detection is a critical part of the MISR mission, but is made more complicated by the fact that there are no spectral channels longward of 866 nm in wavelength. This has led to the development of several novel approaches to cloud detection. For MISR, three independent cloud masks have been developed: the Radiometric Camera-by-camera Cloud Mask (RCCM), the Stereoscopically-Derived Cloud Mask (SDCM), and the Angular Signature Cloud Mask (ASCM). This poster will demonstrate the current status of the three MISR cloud masks and the strengths and weaknesses inherent in each. Methods of evaluating the cloud masks will also be shown, including visible inspection and comparisons with the Moderate Resolution Imaging Spectroradiometer (MODIS). Finally, analyses of the minimum detectable optical depths will be demonstrated, through the use of ground based data.

  2. Cloud Remote Sensing with Sideways-Looks : Theory and First Results Using Multispectral Thermal Imager Data

    SciTech Connect

    Davis, A. B. (Anthony B.)

    2002-01-01

    In operational remote sensing, the implicit model for cloud geometry is a homogeneous plane-parallel slab of infinite horizontal extent. Each pixel is indeed processed as if it exchanged no radiant energy whatsoever with its neighbors. The shortcomings of this conceptual model have been well documented in the specialized literature but rarely mitigated. The worst-case scenario is probably high-resolution imagery where dense isolated clouds are visible, often both bright (reflective) and dark (transmissive) sides being apparent from the same satellite viewing angle: the low transmitted radiance could conceivably be interpreted in plane-parallel theory as no cloud at all. An alternative to the plane-parallel cloud model is introduced here that has the same appeal of being analytically tractable, at least in the diffusion limit: the spherical cloud. This new geometrical paradigm is applied to radiances from cumulus clouds captured by DOE's Multispectral Thermal Imager (MTI). Estimates of isolated cloud opacities are a necessary first step in correcting radiances from surface targets that are visible in the midst of a broken-cloud field. This type of advanced atmospheric correction is badly needed in remote sensing applications such as nonproliferation detection were waiting for a cloud-free look in the indefinite future is not a viable option.

  3. Genetic refinement of cloud-masking algorithms for the multi-spectral thermal imager (MTI)

    SciTech Connect

    Hirsch, K. L. (Karen L.); Davis, A. B. (Anthony B.); Harvey, N. R. (Neal R.); Rohde, C. A. (Charles A.); Brumby, Steven P.

    2001-01-01

    The Multi-spectral Thermal Imager (MTI) is a high-performance remote-sensing satellite designed, owned and operated by the U.S. Department of Energy, with a dual mission in environmental studies and in nonproliferation. It has enhanced spatial and radiometric resolutions and state-of-the-art calibration capabilities. This instrumental development puts a new burden on retrieval algorithm developers to pass this accuracy on to the inferred geophysical parameters. In particular, the atmospheric correction scheme assumes the intervening atmosphere will be modeled as a plane-parallel horizontally-homogeneous medium. A single dense-enough cloud in view of the ground target can easily offset reality from the calculations, hence the need for a reliable cloud-masking algorithm. Pixel-scale cloud detection relies on the simple facts that clouds are generally whiter, brighter, and colder than the ground below; spatially, dense clouds are generally large on some scale. This is a good basis for searching multispectral datacubes for cloud signatures. However, the resulting cloud mask can be very sensitive to the choice of thresholds in whiteness, brightness, temperature, and connectivity. We have used a genetic algorithm trained on (MODIS Airborne Simulator-based) simulated MTI data to design a cloud-mask. Its performance is compared quantitatively to hand-drawn training data and to the EOS/Terra MODIS cloud mask.

  4. Cassini imaging of Titan's high-latitude lakes, clouds, and south-polar surface changes

    Microsoft Academic Search

    E. P. Turtle; J. E. Perry; A. S. McEwen; A. D. Del Genio; J. Barbara; R. A. West; D. D. Dawson; C. C. Porco

    2009-01-01

    Cassini's Imaging Science Subsystem (ISS) has been observing Titan since April 2004, compiling a nearly global surface map and monitoring the surface and atmosphere for activity. Early images of the south-polar region revealed numerous dark surface features and contemporaneous convective cloud systems, suggesting the presence of hydrocarbon lakes similar to those later detected at Titan's North Pole. Intriguingly, repeated south-polar

  5. Cassini imaging of Titan's high-latitude lakes, clouds, and south-polar surface changes

    E-print Network

    Cassini imaging of Titan's high-latitude lakes, clouds, and south-polar surface changes E. P 2009. [1] Cassini's Imaging Science Subsystem (ISS) has been observing Titan since April 2004 observed by Cassini's RADAR. These observations demonstrate dynamic processes at work on Titan

  6. APHELION WATER-ICE CLOUD MAPPING AND PROPERTY RETRIEVAL USING THE OMEGA/MEX IMAGING SPECTROMETER.

    E-print Network

    Madeleine, Jean-Baptiste

    APHELION WATER-ICE CLOUD MAPPING AND PROPERTY RETRIEVAL USING THE OMEGA/MEX IMAGING SPECTROMETER. J possible by the OMEGA (Observa- toire pour la Min´eralogie, l'Eau, les Glaces et l'Activit´e) imaging or the sparsity of observations [1, 2, 3, 4, 5, 6]. Bridging the gap, OMEGA gives an opportunity to study

  7. A MID-INFRARED IMAGING SURVEY OF EMBEDDED YOUNG STELLAR OBJECTS IN THE OPHIUCHI CLOUD CORE

    E-print Network

    Barsony, Mary

    A MID-INFRARED IMAGING SURVEY OF EMBEDDED YOUNG STELLAR OBJECTS IN THE OPHIUCHI CLOUD CORE Mary 2005 April 18 ABSTRACT Results of a comprehensive, new, ground-based mid-infrared imaging survey infall envelopes. Mid-infrared variability is found among a significant fraction of the surveyed objects

  8. Discovering Patterns With and Within Images

    Microsoft Academic Search

    Osmar R. Zaïane

    \\u000a The process of knowledge discovery from data, also known as KDD, comprises steps such as gathering and consolidating data,\\u000a pre-processing then selecting data, mining the selected data, then finally evaluating the discovered patterns for possible\\u000a interpretation and use [28]. To be profitable and constructive, this nontrivial process, which includes the step of data mining, needs to extract implicit,\\u000a previously unknown

  9. A Near-Infrared Imaging Survey of the rho Ophiuchi Cloud Core

    Microsoft Academic Search

    Mary Barsony; Scott J. Kenyon; Elizabeth A. Lada; Peter J. Teuben

    1997-01-01

    We present results of the largest three-color near-infrared (NIR) imaging survey of the rho Ophiuchi star-forming cloud core to date. The survey covers 1 deg2, which corresponds to a projected area of ~2.2 pc x 2.2 pc at the distance of the Ophiuchus clouds (125 +\\/- 25 pc). Mapping was carried out in the J (1.25 mu m), H (1.63

  10. Diurnal, Seasonal, and Interannual Variations of Cloud Properties Derived for CERES From Imager Data

    NASA Technical Reports Server (NTRS)

    Minnis, Patrick; Young, David F.; Sun-Mack, Sunny; Trepte, Qing Z.; Chen, Yan; Brown, Richard R.; Gibson, Sharon; Heck, Patrick W.

    2004-01-01

    Simultaneous measurement of the radiation and cloud fields on a global basis is a key component in the effort to understand and model the interaction between clouds and radiation at the top of the atmosphere, at the surface, and within the atmosphere. The NASA Clouds and Earth s Radiant Energy System (CERES) Project, begun in 1998, is meeting this need. Broadband shortwave (SW) and longwave radiance measurements taken by the CERES scanners at resolutions between 10 and 20 km on the Tropical Rainfall Measuring Mission (TRMM), Terra, and Aqua satellites are matched to simultaneous retrievals of cloud height, phase, particle size, water path, and optical depth OD from the TRMM Visible Infrared Scanner (VIRS) and the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Besides aiding the interpretation of the broadband radiances, the CERES cloud properties are valuable for understanding cloud variations at a variety of scales. In this paper, the resulting CERES cloud data taken to date are averaged at several temporal scales to examine the temporal and spatial variability of the cloud properties on a global scale at a 1 resolution.

  11. Effect of image fiber on the speckle fringe pattern in image fiber-guided DSPI endoscopy

    Microsoft Academic Search

    V. M. Murukeshan; N. Sujatha; L. S. Ong; A. Singh; L. K. Seah

    2007-01-01

    The effect of using an image fiber on the speckle fringe visibility in an endoscopic DSPI is analyzed here. An endoscope system was designed and developed, using image fiber as the speckle pattern image conduit, to work in the out-of-plane speckle interferometric configuration and experiments were carried out using a curved phantom tissue specimen as the test target. Experimental results

  12. Arecibo imaging of compact high-velocity clouds

    NASA Astrophysics Data System (ADS)

    Burton, W. B.; Braun, R.; Chengalur, J. N.

    2001-04-01

    Ten isolated compact high-velocity clouds (CHVCs) of the type cataloged by Braun & Burton (\\cite{brau99}) were imaged with the Arecibo telescope and were found to have a nested core/halo morphology. We argue that a combination of high-resolution filled-aperture and synthesis data is crucial to determining the intrinsic properties of the CHVCs. We identify the halos as Warm Neutral Medium surrounding one or more cores in the Cool Neutral Medium phase. These halos are clearly detected and resolved by the Arecibo filled-aperture imaging, which reaches a limiting sensitivity (1sigma ) of NHIa\\sim 2 1017 cm-2 over the typical 70 kms-1 linewidth at zero intensity. The FWHM linewidth of the halo gas is found to be 25 kms-1, consistent with a WNM thermal broadening within 104 K gas. Substantial asymmetries are found at high NHI (>$1018.5 cm-2) levels in 60% of our sample. A high degree of reflection-symmetry is found at low NHI (<1018.5 cm-2) in all sources studied at these levels. The column-density profiles of the envelopes are described well by the sky-plane projection of a spherical exponential in atomic volume density, which allows estimating the characteristic central halo column density, NHIa(0)=4.1±3.2 1019 cm-2, and characteristic exponential scale-length, hB=420±90 arcsec. For plausible values of the thermal pressure at the CNM/WNM interface, these edge profiles allow distance estimates to be made for the individual CHVCs studied here which range between 150 and 850 kpc. An alternate method of distance estimation utilizing the mean exponential scale-length found in nearby low mass dwarf galaxies, hB=10.6±4.0 kpc, yields distances in the range 320 to 730 kpc. A consequence of having exponential edge profiles is that the apparent size and total flux density of these CHVCs will be strongly dependent on the resolution as well as on the sensitivity of the data used; even a relatively deep observation with a limiting sensitivity of ~1019 cm-2 over 70 kms-1 will detect only the central 30% of the source area and less than 50% of the total flux density. The exponential profiles also suggest that the outer envelopes of the CHVCs are not tidally truncated. Several CHVC cores exhibit a kinematic gradient, consistent with rotation. The halos appear kinematically decoupled from the cores, in the sense that the halos do not display the velocity gradients shown by the dense cores; the gradients are therefore not likely to be due to an external cause such as tidal shear. The much higher degree of symmetry observed in the halos relative to the cores also argues against an external cause of asymmetries in the cores.

  13. Single-pixel optical imaging with compressed reference intensity patterns

    NASA Astrophysics Data System (ADS)

    Chen, Wen; Chen, Xudong

    2015-03-01

    Ghost imaging with single-pixel bucket detector has attracted more and more current attention due to its marked physical characteristics. However, in ghost imaging, a large number of reference intensity patterns are usually required for object reconstruction, hence many applications based on ghost imaging (such as tomography and optical security) may be tedious since heavy storage or transmission is requested. In this paper, we report that the compressed reference intensity patterns can be used for object recovery in computational ghost imaging (with single-pixel bucket detector), and object verification can be further conducted. Only a small portion (such as 2.0% pixels) of each reference intensity pattern is used for object reconstruction, and the recovered object is verified by using nonlinear correlation algorithm. Since statistical characteristic and speckle averaging property are inherent in ghost imaging, sidelobes or multiple peaks can be effectively suppressed or eliminated in the nonlinear correlation outputs when random pixel positions are selected from each reference intensity pattern. Since pixel positions can be randomly selected from each 2D reference intensity pattern (such as total measurements of 20000), a large key space and high flexibility can be generated when the proposed method is applied for authenticationbased cryptography. When compressive sensing is used to recover the object with a small number of measurements, the proposed strategy could still be feasible through further compressing the recorded data (i.e., reference intensity patterns) followed by object verification. It is expected that the proposed method not only compresses the recorded data and facilitates the storage or transmission, but also can build up novel capability (i.e., classical or quantum information verification) for ghost imaging.

  14. Automatic Pattern Extraction and Classification for Chromosome Images

    NASA Astrophysics Data System (ADS)

    Ming, Delie; Tian, Jinwen

    2010-07-01

    Chromosome image analysis and pattern classification is one of the essential tasks in genetic syndrome diagnoses. An automatic procedure is introduced for chromosome image analysis. The pale-path algorithm is proposed to segment touching and overlapping chromosomes. Medial axis is extracted by the middle point algorithm. Chromosome band is enhanced by the algorithm based on multiscale wavelets Bi-spline, and extracted by average gray profile, gradient profile and shape profile. The multilayer classifier is used to classify the chromosome pattern calculated by weighted density distribution algorithm. Experiment results demonstrate that the algorithms perform well.

  15. Automatic registration of Iphone images to LASER point clouds of the urban structures using shape features

    NASA Astrophysics Data System (ADS)

    Sirmacek, B.; Lindenbergh, R. C.; Menenti, M.

    2013-10-01

    Fusion of 3D airborne laser (LIDAR) data and terrestrial optical imagery can be applied in 3D urban modeling and model up-dating. The most challenging aspect of the fusion procedure is registering the terrestrial optical images on the LIDAR point clouds. In this article, we propose an approach for registering these two different data from different sensor sources. As we use iPhone camera images which are taken in front of the interested urban structure by the application user and the high resolution LIDAR point clouds of the acquired by an airborne laser sensor. After finding the photo capturing position and orientation from the iPhone photograph metafile, we automatically select the area of interest in the point cloud and transform it into a range image which has only grayscale intensity levels according to the distance from the image acquisition position. We benefit from local features for registering the iPhone image to the generated range image. In this article, we have applied the registration process based on local feature extraction and graph matching. Finally, the registration result is used for facade texture mapping on the 3D building surface mesh which is generated from the LIDAR point cloud. Our experimental results indicate possible usage of the proposed algorithm framework for 3D urban map updating and enhancing purposes.

  16. D Point Cloud Model Colorization by Dense Registration of Digital Images

    NASA Astrophysics Data System (ADS)

    Crombez, N.; Caron, G.; Mouaddib, E.

    2015-02-01

    Architectural heritage is a historic and artistic property which has to be protected, preserved, restored and must be shown to the public. Modern tools like 3D laser scanners are more and more used in heritage documentation. Most of the time, the 3D laser scanner is completed by a digital camera which is used to enrich the accurate geometric informations with the scanned objects colors. However, the photometric quality of the acquired point clouds is generally rather low because of several problems presented below. We propose an accurate method for registering digital images acquired from any viewpoints on point clouds which is a crucial step for a good colorization by colors projection. We express this image-to-geometry registration as a pose estimation problem. The camera pose is computed using the entire images intensities under a photometric visual and virtual servoing (VVS) framework. The camera extrinsic and intrinsic parameters are automatically estimated. Because we estimates the intrinsic parameters we do not need any informations about the camera which took the used digital image. Finally, when the point cloud model and the digital image are correctly registered, we project the 3D model in the digital image frame and assign new colors to the visible points. The performance of the approach is proven in simulation and real experiments on indoor and outdoor datasets of the cathedral of Amiens, which highlight the success of our method, leading to point clouds with better photometric quality and resolution.

  17. Image Description with Local Patterns: An Application to Face Recognition

    NASA Astrophysics Data System (ADS)

    Zhou, Wei; Ahrary, Alireza; Kamata, Sei-Ichiro

    In this paper, we propose a novel approach for presenting the local features of digital image using 1D Local Patterns by Multi-Scans (1DLPMS). We also consider the extentions and simplifications of the proposed approach into facial images analysis. The proposed approach consists of three steps. At the first step, the gray values of pixels in image are represented as a vector giving the local neighborhood intensity distrubutions of the pixels. Then, multi-scans are applied to capture different spatial information on the image with advantage of less computation than other traditional ways, such as Local Binary Patterns (LBP). The second step is encoding the local features based on different encoding rules using 1D local patterns. This transformation is expected to be less sensitive to illumination variations besides preserving the appearance of images embedded in the original gray scale. At the final step, Grouped 1D Local Patterns by Multi-Scans (G1DLPMS) is applied to make the proposed approach computationally simpler and easy to extend. Next, we further formulate boosted algorithm to extract the most discriminant local features. The evaluated results demonstrate that the proposed approach outperforms the conventional approaches in terms of accuracy in applications of face recognition, gender estimation and facial expression.

  18. High-speed imaging of blood splatter patterns

    SciTech Connect

    McDonald, T.E.; Albright, K.A.; King, N.S.P.; Yates, G.J. (Los Alamos National Lab., NM (United States)); Levine, G.F. (California Dept. of Justice, Sacramento, CA (United States). Bureau of Forensic Services)

    1993-01-01

    The interpretation of blood splatter patterns is an important element in reconstructing the events and circumstances of an accident or crime scene. Unfortunately, the interpretation of patterns and stains formed by blood droplets is not necessarily intuitive and study and analysis are required to arrive at a correct conclusion. A very useful tool in the study of blood splatter patterns is high-speed photography. Scientists at the Los Alamos National Laboratory, Department of Energy (DOE), and Bureau of Forensic Services, State of California, have assembled a high-speed imaging system designed to image blood splatter patterns. The camera employs technology developed by Los Alamos for the underground nuclear testing program and has also been used in a military mine detection program. The camera uses a solid-state CCD sensor operating at approximately 650 frames per second (75 MPixels per second) with a microchannel plate image intensifier that can provide shuttering as short as 5 ns. The images are captured with a laboratory high-speed digitizer and transferred to an IBM compatible PC for display and hard copy output for analysis. The imaging system is described in this paper.

  19. Improvements in Near-Terminator and Nocturnal Cloud Masks using Satellite Image Data over the Atmospheric Radiation Measurement Sites

    NASA Technical Reports Server (NTRS)

    Trepte, Q. Z.; Minnis, P.; Heck, R. W.; Palikonda, R.

    2005-01-01

    Cloud detection using satellite measurements presents a big challenge near the terminator where the visible (VIS; 0.65 (micro)m) channel becomes less reliable and the reflected solar component of the solar infrared 3.9-(micro)m channel reaches very low signal-to-noise ratio levels. As a result, clouds are underestimated near the terminator and at night over land and ocean in previous Atmospheric Radiation Measurement (ARM) Program cloud retrievals using Geostationary Operational Environmental Satellite (GOES) imager data. Cloud detection near the terminator has always been a challenge. For example, comparisons between the CLAVR-x (Clouds from Advanced Very High Resolution Radiometer (AVHRR)) cloud coverage and Geoscience Laser Altimeter System (GLAS) measurements north of 60 degrees N indicate significant amounts of missing clouds from AVHRR because this part of the world was near the day/night terminator viewed by AVHRR. Comparisons between MODIS cloud products and GLAS at the same regions also shows the same difficulty in the MODIS cloud retrieval (Pavolonis and Heidinger 2005). Consistent detection of clouds at all times of day is needed to provide reliable cloud and radiation products for ARM and other research efforts involving the modeling of clouds and their interaction with the radiation budget. To minimize inconsistencies between daytime and nighttime retrievals, this paper develops an improved twilight and nighttime cloud mask using GOES-9, 10, and 12 imager data over the ARM sites and the continental United States (CONUS).

  20. Improvements in Near-Terminator and Nocturnal Cloud Masks using Satellite Imager Data over the Atmospheric Radiation Measurement Sites

    SciTech Connect

    Trepte, Q.Z.; Minnis, P.; Heck, P.W.; Palikonda, R.

    2005-03-18

    Cloud detection using satellite measurements presents a big challenge near the terminator where the visible (VIS; 0.65 {micro}m) channel becomes less reliable and the reflected solar component of the solar infrared 3.9-{micro}m channel reaches very low signal-to-noise ratio levels. As a result, clouds are underestimated near the terminator and at night over land and ocean in previous Atmospheric Radiation Measurement (ARM) Program cloud retrievals using Geostationary Operational Environmental Satellite (GOES) imager data. Cloud detection near the terminator has always been a challenge. For example, comparisons between the CLAVR-x (Clouds from Advanced Very High Resolution Radiometer [AVHRR]) cloud coverage and Geoscience Laser Altimeter System (GLAS) measurements north of 60{sup o}N indicate significant amounts of missing clouds from AVHRR because this part of the world was near the day/night terminator viewed by AVHRR. Comparisons between MODIS cloud products and GLAS at the same regions also shows the same difficulty in the MODIS cloud retrieval (Pavolonis and Heidinger 2005). Consistent detection of clouds at all times of day is needed to provide reliable cloud and radiation products for ARM and other research efforts involving the modeling of clouds and their interaction with the radiation budget. To minimize inconsistencies between daytime and nighttime retrievals, this paper develops an improved twilight and nighttime cloud mask using GOES-9, 10, and 12 imager data over the ARM sites and the continental United States (CONUS).

  1. Virtual dark-field images reconstructed from electron diffraction patterns

    NASA Astrophysics Data System (ADS)

    Rauch, Edgar F.; Véron, Muriel

    2014-04-01

    Bright- and dark-field images are reconstructed by extracting the intensities of selected spots from a succession of digitalized electron diffraction patterns collected using a transmission electron microscope by scanning the focused beam over the area of interest. The procedure is similar to the generation of the scanning-transmission electron microscopy images. Several examples are shown to illustrate the flexibility and potentiality of such numerical off-line reconstruction.

  2. On the camparability of cloud fractions derived from whole sky imager and ceilometer data

    SciTech Connect

    Rodriguez, D.

    1998-01-30

    The Atmospheric Radiation Measurement (ARM) Program`s most heavily instrumented site is its central facility in Lamont, OK. With respect to cloud observations, the instrumentation included a whole sky imager, ceilometers, lidar, millimeter cloud radar, microwave profilers, and radiosondes. Data from three of these instrument--the Whole Sky Imager (WSI), Belfort Laser Ceilometer (BLC) and Micropulse Lidar (MPL)-- are used in this study primarily to investigate the utility of using ceilometers, now strategically emplaced at four additional locations along the perimeter of the site.

  3. Detection and tracking of gas clouds in an urban area by imaging infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Sabbah, Samer; Rusch, Peter; Gerhard, Jörn-Hinnrich; Harig, Roland

    2013-05-01

    The release of toxic industrial compounds in urban areas is a threat for the population and the environment. In order to supply emergency response forces with information about the released compounds after accidents or terrorist attacks, monitoring systems such as the scanning imaging spectrometer SIGIS 2 or the hyperspectral imager HI 90 were developed. Both systems are based on the method of infrared spectroscopy. The systems were deployed to monitor gas clouds released in the harbor area of Hamburg. The gas clouds were identified, visualized and quantified from a distance in real time. Using data of two systems it was possible to identify contaminated areas and to determine the source location.

  4. Hiding a checkered-pattern carrier-screen image in a camouflaged halftone image

    NASA Astrophysics Data System (ADS)

    Shogenji, Rui; Ohtsubo, Junji

    2014-05-01

    As carrier-screen images, we have developed checkered-pattern carrier-screen images, which can be physically decoded by superimposing a checkered pattern. We also proposed a decoding method by image sampling with an ordinary compact digital camera. To obtain a better decoding result, each carrier-screen image should be output at a low resolution. However, secret information can be detected when you observe the image carefully. Thus, a hiding process is an important technique. In this paper, we propose an advanced hiding method by embedding the carrier-screen image into another significant image to generate a camouflaged halftone image. The proposed embedding method can be performed through a simple sequential process of blending and halftoning.

  5. Observation of a cavitation cloud in tissue using correlation between ultrafast ultrasound images.

    PubMed

    Prieur, Fabrice; Zorgani, Ali; Catheline, Stefan; Souchon, Remi; Mestas, Jean-Louis; Lafond, Maxime; Lafon, Cyril

    2015-07-01

    The local application of ultrasound is known to improve drug intake by tumors. Cavitating bubbles are one of the contributing effects. A setup in which two ultrasound transducers are placed confocally is used to generate cavitation in ex vivo tissue. As the transducers emit a series of short excitation bursts, the evolution of the cavitation activity is monitored using an ultrafast ultrasound imaging system. The frame rate of the system is several thousands of images per second, which provides several tens of images between consecutive excitation bursts. Using the correlation between consecutive images for speckle tracking, a decorrelation of the imaging signal appears due to the creation, fast movement, and dissolution of the bubbles in the cavitation cloud. By analyzing this area of decorrelation, the cavitation cloud can be localized and the spatial extent of the cavitation activity characterized. PMID:26168172

  6. Pattern based 3D image Steganography

    NASA Astrophysics Data System (ADS)

    Thiyagarajan, P.; Natarajan, V.; Aghila, G.; Prasanna Venkatesan, V.; Anitha, R.

    2013-03-01

    This paper proposes a new high capacity Steganographic scheme using 3D geometric models. The novel algorithm re-triangulates a part of a triangle mesh and embeds the secret information into newly added position of triangle meshes. Up to nine bits of secret data can be embedded into vertices of a triangle without causing any changes in the visual quality and the geometric properties of the cover image. Experimental results show that the proposed algorithm is secure, with high capacity and low distortion rate. Our algorithm also resists against uniform affine transformations such as cropping, rotation and scaling. Also, the performance of the method is compared with other existing 3D Steganography algorithms. [Figure not available: see fulltext.

  7. High Speed Imaging of Bubble Clouds Generated in Pulsed Ultrasound Cavitational Therapy—Histotripsy

    PubMed Central

    Xu, Zhen; Raghavan, Mekhala; Hall, Timothy L.; Chang, Ching-Wei; Mycek, Mary-Ann; Fowlkes, J. Brian; Cain, Charles A.

    2009-01-01

    Our recent studies have demonstrated that mechanical fractionation of tissue structure with sharply demarcated boundaries can be achieved using short (<20 ?s), high intensity ultrasound pulses delivered at low duty cycles. We have called this technique histotripsy. Histotripsy has potential clinical applications where noninvasive tissue fractionation and/or tissue removal are desired. The primary mechanism of histotripsy is thought to be acoustic cavitation, which is supported by a temporally changing acoustic backscatter observed during the histotripsy process. In this paper, a fast-gated digital camera was used to image the hypothesized cavitating bubble cloud generated by histotripsy pulses. The bubble cloud was produced at a tissue-water interface and inside an optically transparent gelatin phantom which mimics bulk tissue. The imaging shows the following: 1) Initiation of a temporally changing acoustic backscatter was due to the formation of a bubble cloud; 2) The pressure threshold to generate a bubble cloud was lower at a tissue-fluid interface than inside bulk tissue; and 3) at higher pulse pressure, the bubble cloud lasted longer and grew larger. The results add further support to the hypothesis that the histotripsy process is due to a cavitating bubble cloud and may provide insight into the sharp boundaries of histotripsy lesions. PMID:18019247

  8. Active probing of cloud thickness and optical depth using wide-angle imaging LIDAR.

    SciTech Connect

    Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.); Ho, Cheng,

    2002-01-01

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60{sup o} full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Section 2 covers the up-to-date evolution of the nighttime WAIL instrument at LANL. Section 3 reports our progress towards daytime capability for WAIL, an important extension to full diurnal cycle monitoring by means of an ultra-narrow magneto-optic atomic line filter. Section 4 describes briefly how the important cloud properties can be inferred from WAIL signals.

  9. Cloud Ice Crystal Orientation Inferred from Global Precipitation Measurement (GPM) Microwave Imager

    NASA Astrophysics Data System (ADS)

    Gong, J.; Wu, D. L.; Evans, K. F.; Kim, K. M.

    2014-12-01

    Ice crystal orientation can produce significantly different scattering in vertically (V) and horizontally (H) polarized microwave radiances and affect the accuracy of cloud ice measurement. Designed to observe the precipitable-sized particles, GPM Microwave Imager (GMI) is used in this study to infer ice crystal orientation inside ice clouds. By identifying ice cloud scenes using the 183.3±3 GHz channel, we compare the 89 and 166 GHz radiances for their V-H differences. Ice cloud crystals are found highly polarized with V-H > 0 throughout the tropics and the mid-latitude jet regions. The V-H difference can be as large as 10% (5%) of the mean radiance at 166 GHz (89 GHz). The largest values generally occur over convective outflows, but decreasing in the vicinity of deep convective cores and remote thin cirrus regions. The negative V-H values prominently happen in the equator side of the winter hemisphere storm track regions. A polarized radiative transfer model is employed to interpret the observed polarization. Simulations with systematically oriented non-spherical ice particles can reproduce the observed V-H differences, while spherical or randomly oriented non-spherical particles cannot. This finding suggests that accurate cloud ice retrievals must take into account ice crystal orientation. The observed V-H relationship with cloud regimes may relate with vertical velocity, in-cloud turbulence, lightning, and other physical processes, which will be briefly discussed in this presentation.

  10. Characterization of aerosol-containing chemical simulant clouds using a sensitive, thermal infrared imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Hall, Jeffrey L.; D'Amico, Francis M.; Kolodzey, Steven J.; Qian, Jun; Polak, Mark L.; Westerberg, Karl; Chang, Clement S.

    2011-05-01

    A sensitive, ground-based thermal imaging spectrometer was deployed at the Army's Dugway Proving Ground to remotely monitor explosively released chemical-warfare-agent-simulant clouds from stand-off ranges of a few kilometers. The sensor has 128 spectral bands covering the 7.6 to 13.5 micron region. The measured cloud spectra clearly showed scattering of high-elevation-angle sky radiance by liquid aerosols or dust in the clouds: we present arguments that show why the scattering is most likely due to dust. This observation has significant implications for early detection of dust-laden chemical clouds. On one hand, detection algorithms must properly account for the scattered radiation component, which would include out-of-scene radiation components as well as a dust signature; on the other hand, this scattering gives rise to an enhanced "delta-T" for detection by a ground-based sensor.

  11. Automated estimation of mass eruption rate of volcanic eruption on satellite imagery using a cloud pattern recognition algorithm

    NASA Astrophysics Data System (ADS)

    Pouget, Solene; Jansons, Emile; Bursik, Marcus; Tupper, Andrew; Patra, Abani; Pitman, Bruce; Carn, Simon

    2014-05-01

    The need to detect and track the position of ash in the atmosphere has been highlighted in the past few years following the eruption Eyjafjallajokull. As a result, Volcanic Ash Advisory Centers (VAACs) are using Volcanic Ash Transport and Dispersion models (VATD) to estimate and predict the whereabouts of the ash in the atmosphere. However, these models require inputs of eruption source parameters, such as the mass eruption rate (MER), and wind fields, which are vital to properly model the ash movements. These inputs might change with time as the eruption enters different phases. This implies tracking the ash movement as conditions change, and new satellite imagery comes in. Thus, ultimately, the eruption must be detectable, regardless of changing eruption source and meteorological conditions. Volcanic cloud recognition can be particularly challenging, especially when meteorological clouds are present, which is typically the case in the tropics. Given the fact that a large fraction of the eruptions in the world happen in a tropical environment, we have based an automated volcanic cloud recognition algorithm on the fact that meteorological clouds and volcanic clouds behave differently. As a result, the pattern definition algorithm detects and defines volcanic clouds as different object types from meteorological clouds on satellite imagery. Following detection and definition, the algorithm then estimates the area covered by the ash. The area is then analyzed with respect to a plume growth rate methodology to get estimation of the volumetric and mass growth with time. This way, we were able to get an estimation of the MER with time, as plume growth is dependent on MER. To test our approach, we used the examples of two eruptions of different source strength, in two different climatic regimes, and for which therefore the weather during the eruption was quite different: Manam (Papua New Guinea) January 27 2005, which produced a stratospheric umbrella cloud and was difficult to distinguish from meteorological clouds, and Okmok (Alaska) July 12 2008, which was also an umbrella cloud, but started as an ash-rich cloud before getting a vapor rich pulse into the cloud. The new methods may in the future allow for fast, easy and automated detection of volcanic clouds as well as remote assessment of the MER with time, even for inaccessible volcanoes. The methods may thus provide an additional path to estimation of the ESP and the forecasting of ash cloud propagation with time as the eruption changes.

  12. On Dictionary Adaptation for Recurrent Pattern Image Coding

    Microsoft Academic Search

    Nuno M. M. Rodrigues; Eduardo A. B. Da Silva; Murilo B. De Carvalho; Sérgio M. M. De Faria; Vítor Manuel Mendes Da Silva

    2008-01-01

    In this paper, we exploit a recently introduced coding algorithm called multidimensional multiscale parser (MMP) as an alternative to the traditional transform quantization-based methods. MMP uses approximate pattern matching with adaptive multiscale dictionaries that contain concatenations of scaled versions of previously encoded image blocks. We propose the use of predictive coding schemes that modify the source's probability distribution, in order

  13. Atlas of relectance patterns for uniform earth and cloud surfaces (NIMBUS-7ERB-61 days)

    NASA Astrophysics Data System (ADS)

    Taylor, V. R.; Stowe, L. L.

    1984-07-01

    Scanning channel data of the Nimbus-7 ERB instrument have been combined with auxiliary information to describe the radiative characteristics of surfaces as observed through the atmosphere. This information has been recorded on the ERB 'Sub-Target Radiance Tapes' (STRT). A description of that data base and procedures for obtaining the data may be found in Stowe and Fromm (1983). Selected data from the STRTs have been sorted into eight uniform earth and cloud surface types. Diagrams illustrating the bi-directional reflectivity of these surfaces have been constructed. The observed dependence of albedo on solar zenith angle (SZA) is discussed and figures illustrating this dependence are given. An extensive list of references is also given. This report contains a complete set of reflectance diagrams (patterns) and tables listing the values that were used in their construction and interpretation.

  14. CCD camera response to diffraction patterns simulating particle images.

    PubMed

    Stanislas, M; Abdelsalam, D G; Coudert, S

    2013-07-01

    We present a statistical study of CCD (or CMOS) camera response to small images. Diffraction patterns simulating particle images of a size around 2-3 pixels were experimentally generated and characterized using three-point Gaussian peak fitting, currently used in particle image velocimetry (PIV) for accurate location estimation. Based on this peak-fitting technique, the bias and RMS error between locations of simulated and real images were accurately calculated by using a homemade program. The influence of the intensity variation of the simulated particle images on the response of the CCD camera was studied. The experimental results show that the accuracy of the position determination is very good and brings attention to superresolution PIV algorithms. Some tracks are proposed in the conclusion to enlarge and improve the study. PMID:23842270

  15. Directional binary wavelet patterns for biomedical image indexing and retrieval.

    PubMed

    Murala, Subrahmanyam; Maheshwari, R P; Balasubramanian, R

    2012-10-01

    A new algorithm for medical image retrieval is presented in the paper. An 8-bit grayscale image is divided into eight binary bit-planes, and then binary wavelet transform (BWT) which is similar to the lifting scheme in real wavelet transform (RWT) is performed on each bitplane to extract the multi-resolution binary images. The local binary pattern (LBP) features are extracted from the resultant BWT sub-bands. Three experiments have been carried out for proving the effectiveness of the proposed algorithm. Out of which two are meant for medical image retrieval and one for face retrieval. It is further mentioned that the database considered for three experiments are OASIS magnetic resonance imaging (MRI) database, NEMA computer tomography (CT) database and PolyU-NIRFD face database. The results after investigation shows a significant improvement in terms of their evaluation measures as compared to LBP and LBP with Gabor transform. PMID:21822675

  16. Holographic atom imaging from experimental photoelectron angular distribution patterns

    SciTech Connect

    Terminello, L.J. [Lawrence Livermore National Lab., CA (United States); Lapiano-Smith, D.A.; Barton, J.J. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center; Petersen, B.L. [Lawrence Berkeley Lab., CA (United States); Shirley, D.A. [Pennsylvania State Univ., University Park, PA (United States)

    1993-11-01

    One of the most challenging areas of materials research is the imaging of technologically relevant materials with microscopic and atomic-scale resolution. As part of the development of these methods, near-surface atoms in single crystals were imaged using core-level photoelectron holograms. The angle-dependent electron diffraction patterns that constitute an electron hologram were two-dimensionally transformed to create a three dimensional, real-space image of the neighboring scattering atoms. They have made use of a multiple-wavenumber, phased-summing method to improve the atom imaging capabilities of experimental photoelectron holography using the Cu(001) and Pt(111) prototype systems. These studies are performed to evaluate the potential of holographic atom imaging methods as structural probes of unknown materials.

  17. Character and pattern recognition based on moire images

    NASA Astrophysics Data System (ADS)

    Chatterjee, Chanchal; Bieman, Leonard H.

    1995-08-01

    The paper presents a novel method for recognizing raised or indented characters or patterns on industrial samples by using a combination of moire interferometry technique with optical character recognition (OCR) and pattern recognition. Patterns recognized with this method are of low contrast, and conventional recognition schemes require complex optics and lighting. Raised characters on tires, vin code tags, credit cards, indented characters on metal, wrinkles on skin, and embossment on buttons are some examples. The proposed method uses the moire interferometry technique to obtain a gray scale image of patterns such that their heights are represented in gray scale. This eliminates the need for special optics for each application. 3D images obtained as above, are processed by three sets of algorithms: 1) analytical geometry, 2) pattern recognition, and 3) character recognition. The analytical geometry algorithms consist of constrained and unconstrained fitting methods for scattered data, and transformations between different spaces. The pattern recognition methods consist of feature extraction based on scatter matrices, and classification based on hierarchic classification methods. The OCR algorithm employs gray scale correlation. Extension experiments are conducted to support the method.

  18. Global pattern analysis and classification of dermoscopic images using textons

    NASA Astrophysics Data System (ADS)

    Sadeghi, Maryam; Lee, Tim K.; McLean, David; Lui, Harvey; Atkins, M. Stella

    2012-02-01

    Detecting and classifying global dermoscopic patterns are crucial steps for detecting melanocytic lesions from non-melanocytic ones. An important stage of melanoma diagnosis uses pattern analysis methods such as 7-point check list, Menzies method etc. In this paper, we present a novel approach to investigate texture analysis and classification of 5 classes of global lesion patterns (reticular, globular, cobblestone, homogeneous, and parallel pattern) in dermoscopic images. Our statistical approach models the texture by the joint probability distribution of filter responses using a comprehensive set of the state of the art filter banks. This distribution is represented by the frequency histogram of filter response cluster centers called textons. We have also examined other two methods: Joint Distribution of Intensities (JDI) and Convolutional Restricted Boltzmann Machine (CRBM) to learn the pattern specific features to be used for textons. The classification performance is compared over the Leung and Malik filters (LM), Root Filter Set (RFS), Maximum Response Filters (MR8), Schmid, Laws and our proposed filter set as well as CRBM and JDI. We analyzed 375 images of the 5 classes of the patterns. Our experiments show that the joint distribution of color (JDC) in the L*a*b* color space outperforms the other color spaces with a correct classification rate of 86.8%.

  19. Machine learning patterns for neuroimaging-genetic studies in the cloud

    PubMed Central

    Da Mota, Benoit; Tudoran, Radu; Costan, Alexandru; Varoquaux, Gaël; Brasche, Goetz; Conrod, Patricia; Lemaitre, Herve; Paus, Tomas; Rietschel, Marcella; Frouin, Vincent; Poline, Jean-Baptiste; Antoniu, Gabriel; Thirion, Bertrand

    2014-01-01

    Brain imaging is a natural intermediate phenotype to understand the link between genetic information and behavior or brain pathologies risk factors. Massive efforts have been made in the last few years to acquire high-dimensional neuroimaging and genetic data on large cohorts of subjects. The statistical analysis of such data is carried out with increasingly sophisticated techniques and represents a great computational challenge. Fortunately, increasing computational power in distributed architectures can be harnessed, if new neuroinformatics infrastructures are designed and training to use these new tools is provided. Combining a MapReduce framework (TomusBLOB) with machine learning algorithms (Scikit-learn library), we design a scalable analysis tool that can deal with non-parametric statistics on high-dimensional data. End-users describe the statistical procedure to perform and can then test the model on their own computers before running the very same code in the cloud at a larger scale. We illustrate the potential of our approach on real data with an experiment showing how the functional signal in subcortical brain regions can be significantly fit with genome-wide genotypes. This experiment demonstrates the scalability and the reliability of our framework in the cloud with a 2 weeks deployment on hundreds of virtual machines. PMID:24782753

  20. Automatic Registration of Terrestrial Laser Scanning Point Clouds using Panoramic Reflectance Images

    PubMed Central

    Kang, Zhizhong; Li, Jonathan; Zhang, Liqiang; Zhao, Qile; Zlatanova, Sisi

    2009-01-01

    This paper presents a new approach to the automatic registration of terrestrial laser scanning (TLS) point clouds using panoramic reflectance images. The approach follows a two-step procedure that includes both pair-wise registration and global registration. The pair-wise registration consists of image matching (pixel-to-pixel correspondence) and point cloud registration (point-to-point correspondence), as the correspondence between the image and the point cloud (pixel-to-point) is inherent to the reflectance images. False correspondences are removed by a geometric invariance check. The pixel-to-point correspondence and the computation of the rigid transformation parameters (RTPs) are integrated into an iterative process that allows for the pair-wise registration to be optimised. The global registration of all point clouds is obtained by a bundle adjustment using a circular self-closure constraint. Our approach is tested with both indoor and outdoor scenes acquired by a FARO LS 880 laser scanner with an angular resolution of 0.036° and 0.045°, respectively. The results show that the pair-wise and global registration accuracies are of millimetre and centimetre orders, respectively, and that the process is fully automatic and converges quickly. PMID:22574036

  1. Sub-Nyquist Medical Ultrasound Imaging: En Route to Cloud Processing

    E-print Network

    Eldar, Yonina

    Sub-Nyquist Medical Ultrasound Imaging: En Route to Cloud Processing Alon Eilam, Tanya Chernyakova@ee.technion.ac.il GE Healthcare, Haifa, Israel Email: arcady.kempinski@med.ge.com Abstract--In medical ultrasound is feasible for medical ultrasound, leading to potential of considerable reduction in future ultrasound

  2. Cloud top structure of Venus revealed by Subaru/COMICS mid-infrared images

    NASA Astrophysics Data System (ADS)

    Sato, T. M.; Sagawa, H.; Kouyama, T.; Mitsuyama, K.; Satoh, T.; Ohtsuki, S.; Ueno, M.; Kasaba, Y.; Nakamura, M.; Imamura, T.

    2014-04-01

    We have investigated the cloud top structure of Venus by analyzing ground-based images obtained by the Cooled Mid-Infrared Camera and Spectrometer (COMICS), mounted on the 8.2-m Subaru Telescope. In this presentation, we will overview the observational results and discuss their interpretations.

  3. Comparison of eye imaging pattern recognition using neural network

    NASA Astrophysics Data System (ADS)

    Bukhari, W. M.; Syed A., M.; Nasir, M. N. M.; Sulaima, M. F.; Yahaya, M. S.

    2015-05-01

    The beauty of eye recognition system that it is used in automatic identifying and verifies a human weather from digital images or video source. There are various behaviors of the eye such as the color of the iris, size of pupil and shape of the eye. This study represents the analysis, design and implementation of a system for recognition of eye imaging. All the eye images that had been captured from the webcam in RGB format must through several techniques before it can be input for the pattern and recognition processes. The result shows that the final value of weight and bias after complete training 6 eye images for one subject is memorized by the neural network system and be the reference value of the weight and bias for the testing part. The target classifies to 5 different types for 5 subjects. The eye images can recognize the subject based on the target that had been set earlier during the training process. When the values between new eye image and the eye image in the database are almost equal, it is considered the eye image is matched.

  4. Proceedings of the Second Annual Symposium on Mathematical Pattern Recognition and Image Analysis Program

    NASA Technical Reports Server (NTRS)

    Guseman, L. F., Jr. (principal investigator)

    1984-01-01

    Several papers addressing image analysis and pattern recognition techniques for satellite imagery are presented. Texture classification, image rectification and registration, spatial parameter estimation, and surface fitting are discussed.

  5. Multi-Scale Fractal Analysis of Image Texture and Pattern

    NASA Technical Reports Server (NTRS)

    Emerson, Charles W.

    1998-01-01

    Fractals embody important ideas of self-similarity, in which the spatial behavior or appearance of a system is largely independent of scale. Self-similarity is defined as a property of curves or surfaces where each part is indistinguishable from the whole, or where the form of the curve or surface is invariant with respect to scale. An ideal fractal (or monofractal) curve or surface has a constant dimension over all scales, although it may not be an integer value. This is in contrast to Euclidean or topological dimensions, where discrete one, two, and three dimensions describe curves, planes, and volumes. Theoretically, if the digital numbers of a remotely sensed image resemble an ideal fractal surface, then due to the self-similarity property, the fractal dimension of the image will not vary with scale and resolution. However, most geographical phenomena are not strictly self-similar at all scales, but they can often be modeled by a stochastic fractal in which the scaling and self-similarity properties of the fractal have inexact patterns that can be described by statistics. Stochastic fractal sets relax the monofractal self-similarity assumption and measure many scales and resolutions in order to represent the varying form of a phenomenon as a function of local variables across space. In image interpretation, pattern is defined as the overall spatial form of related features, and the repetition of certain forms is a characteristic pattern found in many cultural objects and some natural features. Texture is the visual impression of coarseness or smoothness caused by the variability or uniformity of image tone or color. A potential use of fractals concerns the analysis of image texture. In these situations it is commonly observed that the degree of roughness or inexactness in an image or surface is a function of scale and not of experimental technique. The fractal dimension of remote sensing data could yield quantitative insight on the spatial complexity and information content contained within these data. A software package known as the Image Characterization and Modeling System (ICAMS) was used to explore how fractal dimension is related to surface texture and pattern. The ICAMS software was verified using simulated images of ideal fractal surfaces with specified dimensions. The fractal dimension for areas of homogeneous land cover in the vicinity of Huntsville, Alabama was measured to investigate the relationship between texture and resolution for different land covers.

  6. Automatic analysis of stereoscopic satellite image pairs for determination of cloud-top height and structure

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Strong, J.; Woodward, R. H.; Pierce, H.

    1991-01-01

    Results are presented on an automatic stereo analysis of cloud-top heights from nearly simultaneous satellite image pairs from the GOES and NOAA satellites, using a massively parallel processor computer. Comparisons of computer-derived height fields and manually analyzed fields show that the automatic analysis technique shows promise for performing routine stereo analysis in a real-time environment, providing a useful forecasting tool by augmenting observational data sets of severe thunderstorms and hurricanes. Simulations using synthetic stereo data show that it is possible to automatically resolve small-scale features such as 4000-m-diam clouds to about 1500 m in the vertical.

  7. Direct imaging of a massive dust cloud around R Coronae Borealis

    E-print Network

    Jeffers, S V; Waters, L B F M; Canovas, H; Rodenhuis, M; Ovelar, M De Juan; Chies-Santos, A L; Keller, C U; 10.1051/0004-6361/201117138

    2012-01-01

    We present recent polarimetric images of the highly variable star R CrB using ExPo and archival WFPC2 images from the HST. We observed R CrB during its current dramatic minimum where it decreased more than 9 mag due to the formation of an obscuring dust cloud. Since the dust cloud is only in the line-of-sight, it mimics a coronograph allowing the imaging of the star's circumstellar environment. Our polarimetric observations surprisingly show another scattering dust cloud at approximately 1.3" or 2000 AU from the star. We find that to obtain a decrease in the stellar light of 9 mag and with 30% of the light being reemitted at infrared wavelengths (from R CrB's SED) the grains in R CrB's circumstellar environment must have a very low albedo of approximately 0.07%. We show that the properties of the dust clouds formed around R CrB are best fitted using a combination of two distinct populations of grains size. The first are the extremely small 5 nm grains, formed in the low density continuous wind, and the second...

  8. Imaging Patterns of Brain Development and their Relationship to Cognition.

    PubMed

    Erus, Guray; Battapady, Harsha; Satterthwaite, Theodore D; Hakonarson, Hakon; Gur, Raquel E; Davatzikos, Christos; Gur, Ruben C

    2015-06-01

    We present a brain development index (BDI) that concisely summarizes complex imaging patterns of structural brain maturation along a single dimension using a machine learning methodology. The brain was found to follow a remarkably consistent developmental trajectory in a sample of 621 subjects of ages 8-22 participating in the Philadelphia Neurodevelopmental Cohort, reflected by a cross-validated correlation coefficient between chronologic age and the BDI of r = 0.89. Critically, deviations from this trajectory related to cognitive performance. Specifically, subjects whose BDI was higher than their chronological age displayed significantly superior cognitive processing speed compared with subjects whose BDI was lower than their actual age. These results indicate that the multiparametric imaging patterns summarized by the BDI can accurately delineate trajectories of brain development and identify individuals with cognitive precocity or delay. PMID:24421175

  9. Direct image reconstruction from a Fourier intensity pattern using HERALDO.

    PubMed

    Guizar-Sicairos, Manuel; Fienup, James R

    2008-11-15

    We present what we believe to be the first experimental demonstration of a novel coherent lensless imaging technique: holography with extended reference by autocorrelation linear differential operator. Upon taking derivatives of the field autocorrelation this technique allows the direct reconstruction of an object complex-valued transmissivity from a measurement of its Fraunhofer diffraction pattern. We show reconstruction examples using a parallelogram, a thin slit, and a triangle as extended references. PMID:19015703

  10. An imager-based multispectral retrieval of above-cloud absorbing aerosol optical depth and the optical and microphysical properties of underlying marine stratocumulus clouds

    NASA Astrophysics Data System (ADS)

    Meyer, K.; Platnick, S. E.; Zhang, Z.

    2014-12-01

    Clouds, aerosols, and their interactions are widely considered to be key uncertainty components in our current understanding of the Earth's atmosphere and radiation budget. The work presented here is focused on the quasi-permanent marine boundary layer (MBL) clouds over the southeastern Atlantic Ocean, which underlie a near-persistent smoke layer produced from extensive biomass burning throughout the southern African savanna during austral winter. The absorption of the above-cloud smoke layer, which increases with decreasing wavelength, can introduce biases into imager-based cloud optical and microphysical property retrievals of the underlying MBL clouds. This effect is more pronounced for cloud optical thickness retrievals, which are typically derived from the visible or near-IR wavelength channels (effective particle size retrievals are derived from short and mid-wave IR channels that are less affected by aerosol absorption). Here, a new method is introduced to simultaneously retrieve the above-cloud smoke aerosol optical depth (AOD) and the unbiased cloud optical thickness (COT) and effective radius (CER) using multiple spectral channels in the visible and near- and shortwave-IR. The technique has been applied to MODIS, and retrieval results and statistics, as well as comparisons with other A-Train sensors, are shown.

  11. An Efficient Pattern Substitution Watermarking Method for Binary Images

    NASA Astrophysics Data System (ADS)

    Dong, Keming; Kim, Hyoung-Joong

    In this paper, a method to decrease the size of location map for non-overlapping pattern substitution method is presented. Original pattern substitution (PS) method has been proposed by Ho et al.[1] as a reversible watermarking scheme for binary images. They use a pair of two patterns to embed data. Unfortunately, their location map is huge in size. In our method, we propose an efficient mechanism which can decrease the size of location map considerably for un-overlapping version of the PS method. Experiment results show that our method works well on decreasing the size of location map. Comparison results with the original PS method demonstrate that the proposed method achieves more embedding capacity and higher PSNR value due to the reduced size of the location map.

  12. Extracting Mobile Objects in Images Using a Velodyne LIDAR Point Cloud

    NASA Astrophysics Data System (ADS)

    Vallet, B.; Xiao, W.; Brédif, M.

    2015-03-01

    This paper presents a full pipeline to extract mobile objects in images based on a simultaneous laser acquisition with a Velodyne scanner. The point cloud is first analysed to extract mobile objects in 3D. This is done using Dempster-Shafer theory and it results in weights telling for each points if it corresponds to a mobile object, a fixed object or if no decision can be made based on the data (unknown). These weights are projected in an image acquired simultaneously and used to segment the image between the mobile and the static part of the scene.

  13. Effects of clouds on the Earth radiation budget; Seasonal and inter-annual patterns

    NASA Technical Reports Server (NTRS)

    Dhuria, Harbans L.

    1992-01-01

    Seasonal and regional variations of clouds and their effects on the climatological parameters were studied. The climatological parameters surface temperature, solar insulation, short-wave absorbed, long wave emitted, and net radiation were considered. The data of climatological parameters consisted of about 20 parameters of Earth radiation budget and clouds of 2070 target areas which covered the globe. It consisted of daily and monthly averages of each parameter for each target area for the period, Jun. 1979 - May 1980. Cloud forcing and black body temperature at the top of the atmosphere were calculated. Interactions of clouds, cloud forcing, black body temperature, and the climatological parameters were investigated and analyzed.

  14. Effects of clouds on the Earth radiation budget; Seasonal and inter-annual patterns. Annual report

    SciTech Connect

    Dhuria, H.L.

    1992-12-01

    Seasonal and regional variations of clouds and their effects on the climatological parameters were studied. The climatological parameters surface temperature, solar insulation, short-wave absorbed, long wave emitted, and net radiation were considered. The data of climatological parameters consisted of about 20 parameters of Earth radiation budget and clouds of 2070 target areas which covered the globe. It consisted of daily and monthly averages of each parameter for each target area for the period, Jun. 1979 - May 1980. Cloud forcing and black body temperature at the top of the atmosphere were calculated. Interactions of clouds, cloud forcing, black body temperature, and the climatological parameters were investigated and analyzed.

  15. Application of CloudSat cloud classification maps and MODIS multi-spectral satellite imagery in identifying false rain from satellite images

    NASA Astrophysics Data System (ADS)

    Nasrollahi, N.; Hsu, K.; Sorooshian, S.

    2011-12-01

    In recent years, the emergence of various satellite-based precipitation products with high spatial resolutions and global coverage has resulted in new sources of uninterrupted precipitation estimates. However, due to lack of information on the associated uncertainties and reliability of these products, they are not well integrated into operational and decision making applications. Comparing in-situ rain measurements with satellite precipitation data reveals considerable false alarm in satellite precipitation measurements in the presence of high cold clouds. In this study, application of multi-spectral satellite imagery from MODIS and CloudSat cloud classification maps is investigated to identify false rain detection in satellite precipitation products (e.g., PERSIANN). Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA Earth Observing System Aqua and Terra platform with 36 spectral bands provides valuable information about cloud microphysical characteristics. Additionally, CloudSat, a NASA Earth Sciences Systems Pathfinder (ESSP) mission, is designed to measure vertical structure of clouds from space. The CloudSat radar flies in formation with Aqua with only an average of about 60 s delay. The availability of cloud classes based on CloudSat CLDCLASS product together with multi-spectral capabilities of MODIS makes it possible to create a training data set to distinguish different types of clouds based on their radiances. The training data set is employed to identify high non-precipitating clouds such as cirrus and alto-stratus and remove false precipitation signals in PERSIANN satellite precipitation product. Based on the training data (July 10, 2008 until Sept 10, 2008) more than 12000 single layer cloudy pixels with their spectral characteristics are investigated. In this data set the brightness temperature difference of 8.5 and 11 micrometer channels (BTD[8.5-11]) for cirrus and altos-stratus clouds are more than 2K and 1K respectively. Both of these types of clouds are non-precipitating high that are often miss identified as light rain in the PERSIANN infrared based precipitation algorithm. Finding all pixels with BTD[8.5-11] greater than 1K, the non-precipitating high clouds can be identifies and the estimated precipitation can be removed from the precipitation algorithm. The results suggest a significant improvement in detecting non-precipitating clouds and reducing false precipitation in comparison with radar-based gauge adjusted data over the United States.

  16. The Statistical Analysis of Multi-Voxel Patterns in Functional Imaging

    E-print Network

    Krekelberg, Bart

    The Statistical Analysis of Multi-Voxel Patterns in Functional Imaging Kai Schreiber, Bart States of America Abstract The goal of multi-voxel pattern analysis (MVPA) in BOLD imaging B (2013) The Statistical Analysis of Multi-Voxel Patterns in Functional Imaging. PLoS ONE 8(7): e

  17. Low Clouds and Fog Characterization over Iberian Peninsula using Meteosat Second Generation Images

    NASA Astrophysics Data System (ADS)

    Sánchez, Beatriz; Maqueda, Gregorio

    2014-05-01

    Fog is defined as a collection of suspended water droplets or ice crystals in the air near the Earth's surface that lead to a reduction of horizontal visibility below 1 km (National Oceanic and Atmospheric Administration, 1995). Fog is a stratiform cloud with similar radiative characteristics, for this reason the difference between fog and low stratus clouds is of little importance for remote sensing applications. Fog and low clouds are important atmospheric phenomena, mainly because of their impact on traffic safety and air quality, acting as an obstruction to traffic at land, sea and in the air. The purpose of this work is to develop the method of fog/low clouds detection and analysis on nighttime using Meteosat Second Generation data. This study is focused on the characterization of these atmospheric phenomena in different study cases over the Iberian Peninsula with distinct orography. Firstly, fog/low clouds detection is implemented as a composition of three infrared channels 12.0, 10.8 and 3.9 µm from SEVIRI radiometer on board European geostationary satellite Meteosat (Meteosat-9). The algorithm of detection makes use of a combination of these channels and their differences by creating RGB composites images. On this way, it displays the spatial coverage and location of fog entities. Secondly, this technique allows separating pixels which are indicated as fog/low clouds from clear pixels, assessing the properties of individual pixels using appropriated thresholds of brightness temperature. Thus, it achieves a full analysis of the extent and distribution of fog and its evolution over time. The results of this study have been checked by using ground-based point measurements available as METAR data. Despite the flaws in this sort of inter-comparison approach, the outcome produces to accurate fog/low clouds detection. This work encompasses the way to obtain spatial information from this atmospheric phenomenon by means of satellite imagery.

  18. A wavelet-based method for multifractal image analysis. III. Applications to high-resolution satellite images of cloud structure

    Microsoft Academic Search

    S. G. Roux; A. Arnéodo; N. Decoster

    2000-01-01

    :   We apply the 2D wavelet transform modulus maxima (WTMM) method to high-resolution LANDSAT satellite images of cloudy scenes.\\u000a The computation of the and D(h) multifractal spectra for both the optical depth and the radiance fields confirms the relevance of the multifractal description\\u000a to account for the intermittent nature of marine stratocumulus clouds. When assisting the 2D WTMM method by

  19. BlobCR: Efficient Checkpoint-Restart for HPC Applications on IaaS Clouds using Virtual Disk Image Snapshots

    E-print Network

    Paris-Sud XI, Université de

    BlobCR: Efficient Checkpoint-Restart for HPC Applications on IaaS Clouds using Virtual Disk Image is gain- ing increasing attention for a wide range of scientific high performance computing (HPC that there is an increasing improvement in the scalability and perfor- mance of cloud-based HPC systems [19]. Furthermore, un

  20. Spatially resolved cloud structure on Uranus: Implications of near-IR adaptive optics imaging

    NASA Astrophysics Data System (ADS)

    Sromovsky, L. A.; Fry, P. M.

    2007-12-01

    Seven-band near-IR adaptive optics imaging of Uranus by the Keck II telescope during 2004, with the assistance of selected Hubble Space Telescope images, provides new constraints on the uranian vertical cloud structure and CH 4 mixing ratio, after tuned deconvolutions are applied to remove significant limb darkening distortions. The most strongly absorbing bands approximately agree with the stratospheric haze model of Rages et al. [Rages, K., Pollack, J.B., Tomasko, M.G., Doose, L.R., 1991. Icarus 89, 359-376]. The next most absorbing bands suggest a CH 4 relative humidity of 50-60% above the 1.2-bar condensation level. Window channels imply effective cloud pressures at 12° S that vary from 9 to 3.5 bars, and reflectivity values that vary from 7 to 4%, as the assumed CH 4 mixing ratio varies from 0.75 to 4%. The shape of the center-to-limb radiance profile is in best agreement with the deep cloud being translucent, with relatively low optical depth, and is most consistent with low methane mixing ratios (0.75-1%) if the cloud particles are conservative. Non-conservative particles provide good fits over a wide range of mixing ratios. If C and S are enhanced by the same factor over solar mixing ratios, then the cloud pressures inferred from near-IR observations would be less than H 2S condensation pressures for methane mixing ratios of ˜1.3% or greater. The bright band at 45° S must be partly produced by increased particulate scattering at pressures ˜2 bars to be consistent with its absence in 1.9-?m images and its presence in 0.619-?m images. The reflectivity of the lower clouds declines to nearly negligible values in the northern hemisphere, where I/F observations beyond 50° N are nearly those of a clear atmosphere. The most surprising result is the general lack of scattering originating from the 1.2-bar region where methane is expected to condense. Exceptions occur for discrete features. A large and long-lived discrete feature at 34° S is associated with particulates near 700 mb and ˜4.5 bars. The highest discrete feature, near 26° N, reached pressures ˜200 mb and was eleven times brighter than the background atmosphere in K images.

  1. BOREAS AFM-6 NOAA/ETL 35 GHz Cloud/Turbulence Radar GIF Images

    NASA Technical Reports Server (NTRS)

    Martner, Brooks E.; Newcomer, Jeffrey A. (Editor); Hall, Forrest G.; Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Airborne Fluxes and Meteorology (AFM)-6 team from the National Oceanic and Atmospheric Administration/Environment Technology Laboratory (NOAA/ETL) operated a 35-GHz cloud-sensing radar in the Northern Study Area (NSA) near the Old Jack Pine (OJP) tower from 16 Jul 1994 to 08 Aug 1994. This data set contains a time series of GIF images that show the structure of the lower atmosphere. The NOAA/ETL 35-GHz cloud/turbulence radar GIF images are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  2. Intelligent technique to search for patterns within images in massive databases

    SciTech Connect

    Vega, J.; Murari, A.; Pereira, A.; Portas, A.; Castro, P. [JET-EFDA, Culham Science Center, OX14 3DB Abingdon (United Kingdom)

    2008-10-15

    An image retrieval system for JET has been developed. The image database contains the images of the JET high speed visible camera. The system input is a pattern selected inside an image and the output is the group of frames (defined by their discharge numbers and time slices) that show patterns similar to the selected one. This approach is based on morphological pattern recognition and it should be emphasized that the pattern is found independently of its location in the frame. The technique encodes images into characters and, therefore, it transforms the pattern search into a character-matching problem.

  3. Ultraviolet Imaging Telescope (UIT) Observations of the Small Magellanic Cloud

    Microsoft Academic Search

    Robert H. Cornett; Michael R. Greason; Jesse K. Hill; Joel Wm. Parker; William H. Waller; Ralph C. Bohlin; Kwang-Peng Cheng; Susan G. Neff; Robert W. O'Connell; Morton S. Roberts; Andrew M. Smith; Theodore P. Stecher

    1996-01-01

    A mosaic of four UIT far-UV (FUV; 1620A) images, which covers most of the SMC\\u000abar, is presented, with derived stellar and HII region photometry. The UV\\u000amorphology of the Bar shows that recent star formation there has left striking\\u000afeatures including: a) four concentrations of UV-bright stars spread from\\u000anortheast to southwest at nearly equal (~30 arcmin=0.5 kpc) spacings;

  4. Ultraviolet Imaging Telescope (UIT) Observations of the Small Magellanic Cloud

    Microsoft Academic Search

    Robert H. Cornett; Michael R. Greason; Jesse K. Hill; Joel Wm. Parker; William H. Waller; Ralph C. Bohlin; Kwang-Peng Cheng; Susan G. Neff; Robert W. O'Connell; Morton S. Roberts; Andrew M. Smith; Theodore P. Stecher

    1996-01-01

    A mosaic of four UIT far-UV (FUV; 1620A) images, which covers most of the SMC bar, is presented, with derived stellar and HII region photometry. The UV morphology of the Bar shows that recent star formation there has left striking features including: a) four concentrations of UV-bright stars spread from northeast to southwest at nearly equal (~30 arcmin=0.5 kpc) spacings;

  5. Infrared Cloud Imager Development for Atmospheric Optical Communication Characterization, and Measurements at the JPL Table Mountain Facility

    NASA Astrophysics Data System (ADS)

    Nugent, P. W.; Shaw, J. A.; Piazzolla, S.

    2013-02-01

    The continuous demand for high data return in deep space and near-Earth satellite missions has led NASA and international institutions to consider alternative technologies for high-data-rate communications. One solution is the establishment of wide-bandwidth Earth-space optical communication links, which require (among other things) a nearly obstruction-free atmospheric path. Considering the atmospheric channel, the most common and most apparent impairments on Earth-space optical communication paths arise from clouds. Therefore, the characterization of the statistical behavior of cloud coverage for optical communication ground station candidate sites is of vital importance. In this article, we describe the development and deployment of a ground-based, long-wavelength infrared cloud imaging system able to monitor and characterize the cloud coverage. This system is based on a commercially available camera with a 62-deg diagonal field of view. A novel internal-shutter-based calibration technique allows radiometric calibration of the camera, which operates without a thermoelectric cooler. This cloud imaging system provides continuous day-night cloud detection with constant sensitivity. The cloud imaging system also includes data-processing algorithms that calculate and remove atmospheric emission to isolate cloud signatures, and enable classification of clouds according to their optical attenuation. Measurements of long-wavelength infrared cloud radiance are used to retrieve the optical attenuation (cloud optical depth due to absorption and scattering) in the wavelength range of interest from visible to near-infrared, where the cloud attenuation is quite constant. This article addresses the specifics of the operation, calibration, and data processing of the imaging system that was deployed at the NASA/JPL Table Mountain Facility (TMF) in California. Data are reported from July 2008 to July 2010. These data describe seasonal variability in cloud cover at the TMF site, with cloud amount (percentage of cloudy pixels) peaking at just over 51 percent during February, of which more than 60 percent had optical attenuation exceeding 12 dB at wavelengths in the range from the visible to the near-infrared. The lowest cloud amount was found during August, averaging 19.6 percent, and these clouds were mostly optically thin, with low attenuation.

  6. Micro-patterned quantum dots excitation for cellular microarray imaging

    NASA Astrophysics Data System (ADS)

    Bhave, Gauri; Ng, Elaine; Lee, Youngkyu; Zhang, John X.

    2015-03-01

    We present a compact light source designed for arrayed lab-on-chip cell imaging with the motivation of creating a microchip based system for detection of tumor cells. We aim at creating a multicolor light source that can be integrated for on-chip imaging. Colloidal quantum dots (QDs) were used as the emission layer due to their unique capabilities like multicolor emission, multiple available methods of electrical and photo excitation and compatibility with silicon fabrication were achieved. Micropatterning of QDs was used to create both electrically and photo excited light sources. We study the photo activated source as a robust, high intensity light source which can be easily integrated with lab-onchip systems while requiring additional filters and excitation systems and compare it with an electrically excited source with the capability of individually addressable, multicolor sources on a single substrate eliminating the need for additional optical components. To demonstrate the efficacy of our design, we performed ex vivo transmission mode microscopy to evaluate the nucleus-cytoplasm ratios of cancer cells. We showed the capability of imaging of inner cell structures using multiple wavelengths to perform high contrast imaging and observation. We performed immunofluorescence excitation of MDA-MB 231 cancer cells, cultured in a microwell array. Our method provides patterned multicolor light sources and low cost which are suitable for high-throughput microarray cellular imaging.

  7. MODIS-derived daily PAR simulation from cloud-free images and its validation

    Microsoft Academic Search

    Liangfu Chen; Yanhua Gao; Lei Yang; Qinhuo Liu; Xingfa Gu; Guoliang Tian

    2008-01-01

    In this paper, a MODIS-derived daily PAR (photosynthetically active radiation) simulation model from cloud-free image over land surface has been developed based on Bird and Riordan’s model. In this model, the total downwelling spectral surface irradiance is divided into two parts: one is beam irradiance, and another is diffuse irradiance. The attenuation of solar beam irradiance comprises scattering by the

  8. Current Status of Cloud Masks for the Multi-angle Imaging SpectroRadiometer

    Microsoft Academic Search

    M. J. Wilson; G. Zhao; Y. Yang; B. Chapman; L. di Girolamo

    2004-01-01

    The Multi-angle Imaging SpectroRadiometer (MISR) on-board EOS-Terra makes observations at 9 angles (1 nadir, 8 oblique) in the visible and near-infrared. Cloud detection is a critical part of the MISR mission, but is made more complicated by the fact that there are no spectral channels longward of 866 nm in wavelength. This has led to the development of several novel

  9. Adaptive pattern-based image compression for ultra-low bandwidth weapon seeker image communication

    NASA Astrophysics Data System (ADS)

    Wei, Hai; Zabuawala, Sakina; Varadarajan, Karthik M.; Yadegar, Jacob; Yadegar, Joseph; Gray, David; McCalmont, John; Utt, James

    2009-05-01

    The effectiveness of autonomous munitions systems can be enhanced by transmitting target images to a man-in-the-loop (MITL) as the system deploys. Based on the transmitted images, the MITL could change target priorities or conduct damage assessment in real-time. One impediment to this enhancement realization is the limited bandwidth of the system data-link. In this paper, an innovative pattern-based image compression technology is presented for enabling efficient image transmission over the ultra-low bandwidth system data link, while preserving sufficient details in the decompressed images for the MITL to perform the required assessments. Based on a pattern-driven image model, our technology exploits the structural discontinuities in the image by extracting and prioritizing edge segments with their geometric and intensity profiles. Contingent on the bit budget, only the most salient segments are encoded and transmitted, therefore achieving scalable bit-streams. Simulation results corroborate the technology efficiency and establish its subjective quality superiority over JPEG/JPEG2000 as well as feasibility for real-time implementation. Successful technology demonstrations were conducted using images from surrogate seekers in an aircraft and from a captive-carry test-bed system. The developed technology has potential applications in a broad range of network-enabled weapon systems.

  10. Synergistic use of Imager Window observations for Cloud Clearing of Sounder Observation for INSAT-3D

    NASA Astrophysics Data System (ADS)

    Satapathy, J.; Thapliyal, P. K.; Shukla, M. V.; Kishtawal, C. M.

    2014-11-01

    The retrieval of atmospheric temperature and water vapor profiles from infrared Sounder are severely limited by the presence of cloud. Therefore, retrieval from infrared sounding observations is performed only over clear-sky atmospheric conditions. The probability of finding a clear-sky pixel at spatial resolution of 10 km is found to be very small globally. This study presents a quantitative analysis of the clear-sky probability that is carried out for different months over the Indian region for INSAT-3D Sounder. The probability of a clear-sky is found to be ~7 % for the field of view of 10 km corresponding to the INSAT-3D Sounder. This statistical analysis is established using MODIS cloud mask having 95 % confidence level at 1 km resolution spread in the region between 50E-110E and 30S-30N. This necessitates cloud clearing to remove the effect of partial clouds in the Sounder FOV to provide a clear-sky equivalent sounding retrieval. Various methods were explored to derive the cloud-cleared radiances using supplementary information such as high resolution infrared or microwave observations. This study presents an effort to use the existing traditional method to derive optimal cloudcleared radiances for INSAT-3D Sounder, by estimating the fractional cloud cover using collocated high resolution INSAT-3D Imager window channel observation. The final Sounder cloud-cleared radiances have been validated with the operational AIRS L2 cloud-cleared radiance products. Nevertheless, the statistical analysis of clear-sky probability over Indian region also provides a significant insight towards the dependency of spatial resolution and the considerable field-of-regard (FOR) in obtaining the clear-sky area in the satellite observations. This, in a way, necessitates the cloud-clearing for coarser resolution sensors and at the same time, states the benefits of using very high resolution sensors. It has been observed that FOV of 1km and by choosing a reasonably good FOR can eliminate the cloudy-sky hindrances by increasing the probability of clear-sky from 5 % to 50 %.

  11. Reconstruction of Indoor Models Using Point Clouds Generated from Single-Lens Reflex Cameras and Depth Images

    NASA Astrophysics Data System (ADS)

    Tsai, F.; Wu, T.-S.; Lee, I.-C.; Chang, H.; Su, A. Y. S.

    2015-05-01

    This paper presents a data acquisition system consisting of multiple RGB-D sensors and digital single-lens reflex (DSLR) cameras. A systematic data processing procedure for integrating these two kinds of devices to generate three-dimensional point clouds of indoor environments is also developed and described. In the developed system, DSLR cameras are used to bridge the Kinects and provide a more accurate ray intersection condition, which takes advantage of the higher resolution and image quality of the DSLR cameras. Structure from Motion (SFM) reconstruction is used to link and merge multiple Kinect point clouds and dense point clouds (from DSLR color images) to generate initial integrated point clouds. Then, bundle adjustment is used to resolve the exterior orientation (EO) of all images. Those exterior orientations are used as the initial values to combine these point clouds at each frame into the same coordinate system using Helmert (seven-parameter) transformation. Experimental results demonstrate that the design of the data acquisition system and the data processing procedure can generate dense and fully colored point clouds of indoor environments successfully even in featureless areas. The accuracy of the generated point clouds were evaluated by comparing the widths and heights of identified objects as well as coordinates of pre-set independent check points against in situ measurements. Based on the generated point clouds, complete and accurate three-dimensional models of indoor environments can be constructed effectively.

  12. Hubble space telescope imaging of decoupled dust clouds in the ram pressure stripped Virgo spirals NGC 4402 and NGC 4522

    SciTech Connect

    Abramson, Anne; Kenney, Jeffrey D. P., E-mail: anne.abramson@yale.edu, E-mail: jeff.kenney@yale.edu [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520 (United States)

    2014-03-01

    We present the highest-resolution study to date of the interstellar medium (ISM) in galaxies undergoing ram pressure stripping, using Hubble Space Telescope BVI imaging of NGC 4522 and NGC 4402, Virgo Cluster spirals that are well known to be experiencing intracluster medium (ICM) ram pressure. We find that throughout most of both galaxies, the main dust lane has a fairly well-defined edge, with a population of giant molecular cloud (GMC) sized (tens- to hundreds-of-pc scale), isolated, highly extincting dust clouds located up to ?1.5 kpc radially beyond it. Outside of these dense clouds, the area has little or no diffuse dust extinction, indicating that the clouds have decoupled from the lower-density ISM material that has already been stripped. Several of the dust clouds have elongated morphologies that indicate active ram pressure, including two large (kpc scale) filaments in NGC 4402 that are elongated in the projected ICM wind direction. We calculate a lower limit on the H I + H{sub 2} masses of these clouds based on their dust extinctions and find that a correction factor of ?10 gives cloud masses consistent with those measured in CO for clouds of similar diameters, probably due to the complicating factors of foreground light, cloud substructure, and resolution limitations. Assuming that the clouds' actual masses are consistent with those of GMCs of similar diameters (?10{sup 4}-10{sup 5} M {sub ?}), we estimate that only a small fraction (?1%-10%) of the original H I + H{sub 2} remains in the parts of the disks with decoupled clouds. Based on H? images, a similar fraction of star formation persists in these regions, 2%-3% of the estimated pre-stripping star formation rate. We find that the decoupled cloud lifetimes may be up to 150-200 Myr.

  13. A Time-series Pattern based Noise Generation Strategy for Privacy Protection in Cloud Computing

    E-print Network

    Yang, Yun

    of cloud computing security, there is a need to take special actions to protect privacy at client sides intervals. In this case, service providers may still be able to deduce the customers' privacy from cloud computing in practice [4]. Therefore, security and privacy are critical as one of the most

  14. Imaging spatial correlations of Rydberg excitations in cold atom clouds

    NASA Astrophysics Data System (ADS)

    Schwarzkopf, Andrew; Anderson, David; Raithel, Georg

    2012-06-01

    We measure correlations between excitation positions in cold Rydberg gases. We have previously observedootnotetextmark[2] Rydberg-blockade-induced structures in the Rydberg pair correlation function similar to those predicted in.ootnotetextmark[3] Here, we study the effect of Coulomb repulsion after field ionization, which could possibly influence the pair correlation measurement. We have simulated the ion trajectories in our chamber and determined that Coulomb repulsion did not play a role in any of our previous experiments. However, with higher magnification we expect to observe this effect as well. In the experiment, we already have obtained a magnification increase by about a factor of two, and progress towards even higher magnification is still being made. We will report on our progress in imaging smaller structures in the pair correlation function, induced by Coulomb repulsion and possibly by adiabatic Rydberg crystal formation.ootnotetextmark[4] ootnotetext[2]A. Schwarzkopf et al. Phys. Rev. Lett. 107, no. 10 (2011): 103001. ootnotetext[3]F. Robicheaux and J. Hernandez. Phys. Rev. A 72, 63403, 1-4 (2005). ootnotetext[4]T. Pohl et al. Phys. Rev. Lett. 104, no. 4 (January 27, 2010): 043002.

  15. Multi Spectral Pushbroom Imaging Radiometer (MPIR) for remote sensing cloud studies

    SciTech Connect

    Phipps, G.S.; Grotbeck, C.L.

    1995-10-01

    A Multi Spectral Pushbroom Imaging Radiometer (MPIR) has been developed as are relatively inexpensive ({approximately}$IM/copy), well-calibrated,imaging radiometer for aircraft studies of cloud properties. The instrument is designed to fly on an Unmanned Aerospace Vehicle (UAV) platform at altitudes from the surface up to 20 km. MPIR is being developed to support the Unmanned Aerospace Vehicle portion of the Department of Energy`s Atmospheric Radiation Measurements program (ARM/UAV). Radiation-cloud interactions are the dominant uncertainty in the current General Circulation Models used for atmospheric climate studies. Reduction of this uncertainty is a top scientific priority of the US Global Change Research Program and the ARM program. While the DOE`s ARM program measures a num-ber of parameters from the ground-based Clouds and Radiation Testbed sites, it was recognized from the outset that other key parameters are best measured by sustained airborne data taking. These measurements are critical in our understanding of global change issues as well as for improved atmospheric and near space weather forecasting applications.

  16. Two Methods for Retrieving UV Index for All Cloud Conditions from Sky Imager Products or Total SW Radiation Measurements

    SciTech Connect

    Badosa, Jordi; Calbo, J.; McKenzie, R. L.; Liley, Ben; Gonzalez, J. A.; Forgan, B. W.; Long, Charles N.

    2014-07-01

    In the present study, we assess the cloud effects on UV Index (UVI) and total solar radiation (TR) as a function of cloud cover estimations and sunny conditions (from sky imaging products) as well as of solar zenith angle (SZA). These analyses are undertaken for a southern-hemisphere mid-latitude site where a 10-years dataset is available. It is confirmed that clouds reduce TR more than UV, in particular for obscured Sun conditions, low cloud fraction (< 60%) and large SZA (> 60º). Similarly, clouds enhance TR more than UV, mainly for visible Sun conditions, large cloud fraction and large SZA. Two methods to estimate UVI are developed: 1) from sky imaging cloud cover and sunny conditions, and 2) from TR measurements. Both methods may be used in practical operational applications, although Method 2 shows overall the best performance, since TR allows accounting for cloud optical properties. The mean absolute differences of Method 2 estimations with respect to measured values are 0.17 UVI units (for 1-minute data) and 0.79 Standard Erythemal Dose (SED) units (for daily integrations). Method 1 shows less accurate results but it is still suitable to estimate UVI: mean absolute differences are 0.37 UVI units and 1.6 SED.

  17. Hubble Space Telescope Images of Magellanic Cloud Planetary Nebulae: Data and Correlations across Morphological Classes

    E-print Network

    L. Stanghellini; J. C. Blades; S. J. Osmer; M. J. Barlow; X. -W. Liu

    1998-06-30

    The morphology of planetary nebulae (PNe) provides an essential tool for understanding their origin and evolution, as it reflects both the dynamics of the gas ejected during the TP-AGB phase, and the central star energetics. Here we study the morphology of 27 Magellanic Cloud planetary nebulae (MCPNe) and present an analysis of their physical characteristics across morphological classes. Similar studies have been successfully carried out for galactic PNe, but were compromised by the uncertainty of individual PN distances. We present our own HST/FOC images of 15 Magellanic Cloud PNe (MCPNe) acquired through a narrow-band lambda 5007 [O III] filter. We use the Richardson-Lucy deconvolution technique on these pre-COSTAR images to achieve post-COSTAR quality. Three PNe imaged before and after COSTAR confirm the high reliability of our deconvolution procedure. We derive morphological classes, dimensions, and surface photometry for all these PNe. We have combined this sample with HST/PC1 images of 15 MCPNe, three of which are in common with the FOC set, acquired by Dopita et al. (1996), to obtain the largest MCPN sample ever examined from the morphological viewpoint. By using the whole database, supplemented with published data from the literature, we have analyzed the properties of the MCPNe and compared them to a typical, complete galactic sample. Morphology of the MCPNe is then correlated with PN density, chemistry, and evolution.

  18. Automated method for the removal of unwanted nonperiodic patterns from forensic images

    Microsoft Academic Search

    David Capel; Andrew Zisserman; Simon K. Bramble; David Compton

    1999-01-01

    The aim of this work is the removal of distracting background patterns from forensic evidence so that the evidence is rendered more visible. An example is the image of a finger print on a non-periodic background. The method involves registering the image with a control image of the background pattern that we seek to remove. A statistical comparison of the

  19. A novel method of intelligent analysis of weave pattern based on image processing technology

    Microsoft Academic Search

    Xinxing Tu; Ping Zhong; Binjie Xin; Shile Wang

    2011-01-01

    This paper proposed a new method based on image processing and pattern recognition technology to recognize the pattern of woven fabric. The method disposed the information of both the top and bottom fabric images. The result of analyzing the regularity of the intensity variation of the horizontal and vertical direction of image can be used to determine the interlacing position

  20. Teaching image processing and pattern recognition with the Intel OpenCV library

    Microsoft Academic Search

    Adam Kozlowski; Aleksandra Królak

    2009-01-01

    In this paper we present an approach to teaching image processing and pattern recognition with the use of the OpenCV library. Image processing, pattern recognition and computer vision are important branches of science and apply to tasks ranging from critical, involving medical diagnostics, to everyday tasks including art and entertainment purposes. It is therefore crucial to provide students of image

  1. SKA memo 103, 14 aug 2008 Deconvolving Primary Beam Patterns from SKA Images

    E-print Network

    Militzer, Burkhard

    SKA memo 103, 14 aug 2008 Deconvolving Primary Beam Patterns from SKA Images Melvyn Wright present a method for deconvolving the primary beam response from interferometric images of astronomical distribution weighted by the measured primary beam pattern, the residual uv data can be re-imaged to provide

  2. Deep Convective Clouds

    NSDL National Science Digital Library

    Convective clouds are clouds that develop vertically appearing like big stacks of clouds. One very common example is cumulonimbus clouds. Convective clouds are commonly connected to stormy weather. Monthly Cloud Coverage for Deep Convective Cloud data can be used to predict patterns in weather. The specific pattern associated with this data is tracking and predicting thunderstorms. In this lesson, the students will take a look at the Monthly Cloud Coverage for Deep Convective Cloud data, and name one month of the year 'Thunderstorm Season' for their continent.

  3. Algorithms for pattern recognition in images of cell cultures

    NASA Astrophysics Data System (ADS)

    Mendes, Joyce M.; Peixoto, Nathalia L.; Ramirez-Fernandez, Francisco J.

    2001-06-01

    Several applications of silicon microstructures in areas such as neurobiology and electrophysiology have been stimulating the development of microsystems with the objective of mechanical support to monitor and control several parameters in cell cultures. In this work a multi-microelectrode arrays was fabricated over a glass plate to obtain the growth of neuronal cell monitoring their behavior during cell development. To identify the neuron core and axon an approach for implementation of edge detectors algorithms associated to images is described. The necessity of efficient and reliable algorithms for image processing and interpretation is justified by its large field of applications in several areas as well as medicine, robotics, cellular biology, computational vision and pattern recognition. In this work, it is investigated the adequacy of some edge detectors algorithms such as Canny, Marr-Hildreth. Some alterations in those methods are propose to improve the identification of both cell core and axonal growth measure. We compare the operator to edge detector proposed by Canny, Marr-Hildreth operator and application of Hough Transform. For evaluation of algorithms adaptations, we developed a method for automatic cell segmentation and measurement. Our goal is to find a set of parameters defining the location of the objects to compare the original and processed images.

  4. Imaging Dot Patterns for Measuring Gossamer Space Structures

    NASA Technical Reports Server (NTRS)

    Dorrington, A. A.; Danehy, P. M.; Jones, T. W.; Pappa, R. S.; Connell, J. W.

    2005-01-01

    A paper describes a photogrammetric method for measuring the changing shape of a gossamer (membrane) structure deployed in outer space. Such a structure is typified by a solar sail comprising a transparent polymeric membrane aluminized on its Sun-facing side and coated black on the opposite side. Unlike some prior photogrammetric methods, this method does not require an artificial light source or the attachment of retroreflectors to the gossamer structure. In a basic version of the method, the membrane contains a fluorescent dye, and the front and back coats are removed in matching patterns of dots. The dye in the dots absorbs some sunlight and fluoresces at a longer wavelength in all directions, thereby enabling acquisition of high-contrast images from almost any viewing angle. The fluorescent dots are observed by one or more electronic camera(s) on the Sun side, the shade side, or both sides. Filters that pass the fluorescent light and suppress most of the solar spectrum are placed in front of the camera(s) to increase the contrast of the dots against the background. The dot image(s) in the camera(s) are digitized, then processed by use of commercially available photogrammetric software.

  5. Forecasting for Grid and Cloud Computing On-Demand Resources Based on Pattern Matching

    Microsoft Academic Search

    Eddy Caron; Frédéric Desprez; Adrian Muresan

    2010-01-01

    Abstract: The Cloud phenomenon,brings along the cost-saving benefit of dynamic scaling. Knowledge in advance is necessary as the virtual resources that Cloud computing uses have a setup time that is not negligible. We propose a new approach to the problem of workload prediction based on identifying similar past occurrences to the current short-term workload history. We present in detail the

  6. Measurement of Aerosol and Cloud Particles with PACS and HARP Hyperangular Imaging Polarimeters

    NASA Astrophysics Data System (ADS)

    Martins, J.; Fernandez-Borda, R.; Remer, L. A.; Sparr, L.; Buczkowski, S.; Munchak, L. A.

    2013-12-01

    PACS is new hyper-angular imaging polarimeter for aeorosol and cloud measurerents designed to meet the requirements of the proposed ACE decadal survey mission. The full PACS system consists of three wide field of view (110deg cross track) telescopes covering the UV, VNIR, and SWIR spectral ranges with angular coverage between +55 deg forward to -55deg backwards. The angular density can be selected to cover up to 100 different viewing angles at selected wavelengths. PACS_VNIR is a prototype airborne instrument designed to demonstrate PACS capability by deploying just one of the three wavelength modules of the full PACS. With wavelengths at 470, 550, 675, 760 and 875nm, PACS_VNIR flew for the first time during the PODEX experiment in January/February 2013 aboard the NASA ER-2 aircraft. PACS SWIR (1.64, 1.88, 2.1, and 2.25um) is currently under construction and should be operational in the lab by Fall/2013. PACS_ UV has been fully designed, but is not yet under construction. During the PODEX flights PACS_VNIR collected data for aerosol and clouds over variable surface types including, water, vegetation, urban areas, and snow. The data is currently being calibrated, geolocated and prepared for the inversion of geophysical parameters including water cloud size distribution and aerosol microphysical parameters. The large density of angles in PACS allows for the characterization of cloudbow features in relatively high spatial resolution in a pixel to pixel basis. This avoids the need for assumptions of cloud homogeneity over any distance. The hyperangle capability also allows detailed observation of cloud ice particles, surface characterization, and optimum selection of the number of angles desired for aerosol retrievals. The aerosol and cloud retrieval algorithms under development for the retrieval of particle microphysical properties from the PACS data will be discussed in this presentation. As an extension of the PACS concept we are currently developing the HARP (Hyper-Angular Rainbow Polarimeter) Cubesat satellite funded by the NASA/ESTO/InVEST program. HARP will demonstrate the PACS concept from space and will allow for high resolution angular measurements of polarized radiances over different aerosol and cloud scenarios. The HARP concept and strategy will be presented and discussed as part of the general PACS measurement strategy.

  7. 3D imaging of antenna fields from electronically synthesised scalar intensity patterns

    Microsoft Academic Search

    D. Smith; M. Leach

    2003-01-01

    This work describes a new technique for the determination of antenna far field radiation patterns and the imaging of antenna fields from holographic intensity patterns. These intensity patterns are obtained by combining the sampled antenna near field with an electronically synthesised offset reference plane wave. The resultant intensity pattern can be recorded in a fast and inexpensive manner. This work

  8. Estimation of fractional cloud cover for Moderate Resolution Imaging Spectroradiometer\\/Terra cloud mask classes with high-resolution over ocean ASTER observations

    Microsoft Academic Search

    Andrzej Z. Kotarba

    2010-01-01

    Cloud masks are the final product of cloud detection and the starting point for determining the cloud amount. To calculate the cloud amount within thematic classes of cloud masks, the cloud fraction for each class must be assigned. This is usually done subjectively, assuming that clear pixels indicate a cloud fraction value of 0.0 and cloudy pixels indicate a cloud

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

    DOEpatents

    Perry, Michael D. (Downy, CA)

    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.

  10. Laser point cloud diluting and refined 3D reconstruction fusing with digital images

    NASA Astrophysics Data System (ADS)

    Liu, Jie; Zhang, Jianqing

    2007-06-01

    This paper shows a method to combine the imaged-based modeling technique and Laser scanning data to rebuild a realistic 3D model. Firstly use the image pair to build a relative 3D model of the object, and then register the relative model to the Laser coordinate system. Project the Laser points to one of the images and extract the feature lines from that image. After that fit the 2D projected Laser points to lines in the image and constrain their corresponding 3D points to lines in the 3D Laser space to keep the features of the model. Build TIN and cancel the redundant points, which don't impact the curvature of their neighborhood areas. Use the diluting Laser point cloud to reconstruct the geometry model of the object, and then project the texture of corresponding image onto it. The process is shown to be feasible and progressive proved by experimental results. The final model is quite similar with the real object. This method cuts down the quantity of data in the precondition of keeping the features of model. The effect of it is manifest.

  11. A QR Code Based Zero-Watermarking Scheme for Authentication of Medical Images in Teleradiology Cloud

    PubMed Central

    Seenivasagam, V.; Velumani, R.

    2013-01-01

    Healthcare institutions adapt cloud based archiving of medical images and patient records to share them efficiently. Controlled access to these records and authentication of images must be enforced to mitigate fraudulent activities and medical errors. This paper presents a zero-watermarking scheme implemented in the composite Contourlet Transform (CT)—Singular Value Decomposition (SVD) domain for unambiguous authentication of medical images. Further, a framework is proposed for accessing patient records based on the watermarking scheme. The patient identification details and a link to patient data encoded into a Quick Response (QR) code serves as the watermark. In the proposed scheme, the medical image is not subjected to degradations due to watermarking. Patient authentication and authorized access to patient data are realized on combining a Secret Share with the Master Share constructed from invariant features of the medical image. The Hu's invariant image moments are exploited in creating the Master Share. The proposed system is evaluated with Checkmark software and is found to be robust to both geometric and non geometric attacks. PMID:23970943

  12. A QR code based zero-watermarking scheme for authentication of medical images in teleradiology cloud.

    PubMed

    Seenivasagam, V; Velumani, R

    2013-01-01

    Healthcare institutions adapt cloud based archiving of medical images and patient records to share them efficiently. Controlled access to these records and authentication of images must be enforced to mitigate fraudulent activities and medical errors. This paper presents a zero-watermarking scheme implemented in the composite Contourlet Transform (CT)-Singular Value Decomposition (SVD) domain for unambiguous authentication of medical images. Further, a framework is proposed for accessing patient records based on the watermarking scheme. The patient identification details and a link to patient data encoded into a Quick Response (QR) code serves as the watermark. In the proposed scheme, the medical image is not subjected to degradations due to watermarking. Patient authentication and authorized access to patient data are realized on combining a Secret Share with the Master Share constructed from invariant features of the medical image. The Hu's invariant image moments are exploited in creating the Master Share. The proposed system is evaluated with Checkmark software and is found to be robust to both geometric and non geometric attacks. PMID:23970943

  13. Using Geotags to Derive Rich Tag-Clouds for Image Annotation

    NASA Astrophysics Data System (ADS)

    Joshi, Dhiraj; Luo, Jiebo; Yu, Jie; Lei, Phoury; Gallagher, Andrew

    Geotagging has become popular for many multimedia applications. In this chapter, we present an integrated and intuitive system for location-driven tag suggestion, in the form of tag-clouds, for geotagged photos. Potential tags from multiple sources are extracted and weighted. Sources include points of interest (POI) tags from a public Geographic Names Information System (GNIS) database, community tags from Flickr® pictures, and personal tags shared through users' own, family, and friends' photo collections. To increase the effectiveness of GNIS POI tags, bags of place-name tags are first retrieved, clustered, and then re-ranked using a combined tf-idf and spatial distance criteria. The community tags from photos taken in the vicinity of the input geotagged photo are ranked according to distance and visual similarity to the input photo. Personal tags from other personally related photos inherently carry a significant weight due more to their high relevance than to both the generic place-name tags and community tags, and are ranked by weights that decay over time and distance differences. Finally, a rich set of the most relevant location-driven tags is presented to the user in the form of individual tag clouds under the three mentioned source categories. The tag clouds act as intuitive suggestions for tagging an input image. We also discuss quantitative and qualitative findings from a user study that we conducted. Evaluation has revealed the respective benefits of the three categories toward the effectiveness of the integrated tag suggestion system.

  14. Partially overlapped range images registration based on Fringe pattern profilometry

    NASA Astrophysics Data System (ADS)

    He, Xiaochen; Xi, Jiangtao; Yu, Yanguang

    2011-11-01

    Registration of two three-dimensional (3-D) point sets is a fundamental problem of 3-D shape measurement and modeling pipeline. This paper investigates the automatic pair-wise method to register partially overlapped range images generated by self-developed fringe pattern profilometry (FPP) system. The method is based on the classic iterative closest point (ICP) algorithm but combined with several extensions to adapt to the experimental data. Firstly, the distance function for correspondence finding is modified to be the weighted linear combination of positions and Euclidean invariant features for improving the probability of convergence. In addition, outliers can be discarded through robust statistics and adaptive thresholding of weighted distances between corresponding point pairs. Both artificial and real data are used to test the proposed method. In the ideal noise-free conditions, the experimental results illustrate that it converges to the global minima. The experimental results also show that the proposed method increases the possibility of global convergence when deal with partially overlapped range images.

  15. Integration of Point Clouds Originated from Laser Scaner and Photogrammetric Images for Visualization of Complex Details of Historical Buildings

    NASA Astrophysics Data System (ADS)

    Altuntas, C.

    2015-02-01

    Three-dimensional (3D) models of historical buildings are created for documentation and virtual realization of them. Laser scanning and photogrammetry are extensively used to perform for these aims. The selection of the method that will be used in threedimensional modelling study depends on the scale and shape of the object, and also applicability of the method. Laser scanners are high cost instruments. However, the cameras are low cost instruments. The off-the-shelf cameras are used for taking the photogrammetric images. The camera is imaging the object details by carrying on hand while the laser scanner makes ground based measurement. Laser scanner collect high density spatial data in a short time from the measurement area. On the other hand, image based 3D (IB3D) measurement uses images to create 3D point cloud data. The image matching and the creation of the point cloud can be done automatically. Historical buildings include more complex details. Thus, all details cannot be measured by terrestrial laser scanner (TLS) due to the blocking the details with each others. Especially, the artefacts which have complex shapes cannot be measured in full details. They cause occlusion on the point cloud model. However it is possible to record photogrammetric images and creation IB3D point cloud for these areas. Thus the occlusion free 3D model is created by the integration of point clouds originated from the TLS and photogrammetric images. In this study, usability of laser scanning in conjunction with image based modelling for creation occlusion free three-dimensional point cloud model of historical building was evaluated. The IB3D point cloud was created in the areas that could not been measured by TLS. Then laser scanning and IB3D point clouds were integrated in the common coordinate system. The registration point clouds were performed with the iterative closest point (ICP) and georeferencing methods. Accuracy of the registration was evaluated by convergency and its standard deviations for the ICP and residuals on the control points for the georeferencing method.

  16. Automated method for the removal of unwanted nonperiodic patterns from forensic images

    NASA Astrophysics Data System (ADS)

    Capel, David; Zisserman, Andrew; Bramble, Simon K.; Compton, David

    1999-02-01

    The aim of this work is the removal of distracting background patterns from forensic evidence so that the evidence is rendered more visible. An example is the image of a finger print on a non-periodic background. The method involves registering the image with a control image of the background pattern that we seek to remove. A statistical comparison of the registered images identifies the latent mark.

  17. A method of using commercial virtual satellite image to check the pattern painting spot effect

    NASA Astrophysics Data System (ADS)

    Wang, Zheng-gang; Kang, Qing; Shen, Zhi-qiang; Cui, Chang-bin

    2014-02-01

    A method of using commercial virtual satellite image to check the pattern painting spot effect contrast with the satellite images before painting and after painting have been discussed. Using a housetop as the testing platform analyses and discusses the factors' influence such as resolution of satellite image, spot size and color of pattern painting spot and pattern painting camouflage method choosing to the plan implement. The pattern painting design and spot size used in the testing has been ensured, and housetop pattern painting has been painted. Finally, the small spot pattern painting camouflage effect of engineering using upon painting pattern size, color and texture have been checked, contrasting with the satellite image before painting and after painting.

  18. Calibration and Laboratory Test of the Department of Energy Cloud Particle Imager

    SciTech Connect

    McFarquhar, GM; Um, J

    2012-02-17

    Calibration parameters from the Connolly et al. (2007) algorithm cannot be applied to the Department of Energy's (DOE) CPI because the DOE CPI is version 2.0. Thus, Dr. Junshik Um and Prof. Greg McFarquhar brought the DOE CPI to the University of Manchester, UK, where facilities for calibrating it were available. In addition, two other versions of CPIs (1.0 and 1.5) were available on-site at the University of Manchester so that an intercomparison of three different versions of the CPI was possible. The three CPIs (versions 1.0, 1.5, and 2.0) were calibrated by moving glass calibration beads and ice analogues of known size parallel to the object plane. The distance between the object plane and a particle, the particle's focus, its apparent maximum dimension, and a background image were measured in order to derive calibration parameters for each CPI version. The calibration parameters are used in two empirical equations that are applied to in situ CPI data to determine particle size and depth of field, and hence particle size distributions (PSDs). After the tests with the glass calibration beads to derive the calibration parameters, the three CPIs were installed at the base of the Manchester Ice Cloud Chamber and connected to air pumps that drew cloud through the sample volume. Warm liquid clouds at a temperature of 1-2 C and ice clouds at a temperature of -5 C were generated, and the resulting PSDs for each of the CPIs were determined by applying the results of each calibration.

  19. Wire Structure Pattern Extraction and Tracking From X-Ray Images of composite Mechanisms

    E-print Network

    Tschumperlé, David

    Wire Structure Pattern Extraction and Tracking From X-Ray Images of composite Mechanisms D). Figure 1. One of the acquired X-ray image of a composite sample. The analysis of acquired X-ray images in the acquired 1French Atomic Energy Comission (CEA). 1 #12;image. This is due to the fact that the X-ray system

  20. Detecting Digital Image Forgeries Using Sensor Pattern Noise Jan Luks, Jessica Fridrich, and Miroslav Goljan

    E-print Network

    Fridrich, Jessica

    Detecting Digital Image Forgeries Using Sensor Pattern Noise Jan Lukás, Jessica Fridrich-6000 ABSTRACT We present a new approach to detection of forgeries in digital images under the assumption forgeries and on non-forged images. We also investigate how further image processing applied to the forged

  1. Introducing spatial information in k-means algorithm for cloud detection in optical satellite images

    NASA Astrophysics Data System (ADS)

    Beaudoin, Laurent; Nicolas, Jean-Marie; Tupin, Florence; Hueckel, M.

    2001-01-01

    Due to restricted visibility time of remote sensing polar platforms from earth reception station, on ly a limited number of images can be transmitted. On the case of optical images, an in- board cloud cover detection module will allow to transmit only useful images. In order to derive such a module, we propose a method to detect cloudy areas from subsampled images. For a pixel ground surface of about 110 by 100 m2, cloudy areas appear as the highest radiometric value homogeneous areas. The algorithm presented in this paper is based on the k-means Method. Its main originality is to improve classical results by introducing isotropic spatial information. Input data are the sorted components of a vector composed of radiometric values for each pixel and its neighbors. Then a classical k-means method with constraints on the cloudy class gravity center is used on these vectors. We tested the method on a set of 206 subsampled SPOT XS and 138 SPOT P images and their manmade interpretation masks. To evaluate the quality of our results, we used the probability of false alarm (PFA) depending on the number of pixels which have been wrongly declared cloudy. We obtained rather good PFA and PND, and compared these values with result obtained with other methods.

  2. Parallax correction in collocating CloudSat and Moderate Resolution Imaging Spectroradiometer (MODIS) observations: Method and application to convection study

    NASA Astrophysics Data System (ADS)

    Wang, Chunpeng; Luo, Zhengzhao Johnny; Huang, Xianglei

    2011-09-01

    Parallax is associated with an apparent shift of the position of an object when viewed from different angles. For satellite observations, especially observations with clouds, it affects collocation of measurements from different platforms. In this study, we investigate how the parallax problem affects the collocation of CloudSat and Moderate Resolution Imaging Spectroradiometer (MODIS) observations of tropical convective clouds by examining the impact of parallax correction on statistics of convective cloud properties such as cloud top temperature (CTT) and buoyancy. Previous studies circumvented the parallax problem by imposing a "flat-top" condition on the selection of convective clouds, but it inadvertently biases the statistics toward convections at mature or dissipating stages when convective plumes cease to grow but flatten out to form cirrus anvils. The main findings of this study are the following: (1) Parallax correction reduces CTT of convective clouds; the magnitude of the reduction increases with cloud top height (CTH). (2) Parallax correction also reduces the spread of CTT estimates, making it more closely clustered around the corresponding CTH. (3) The fraction of convection with positive buoyancy decreases after the parallax correction. All these changes that are due to parallax correction are most pronounced for convections above 10-12 km, highlighting the importance of parallax correction in satellite-based study of deep convection. With parallax correction applied, we further examine the contrast in convective cloud buoyancy between land and ocean and day and night and the dependence on convective cloud size; results are consistent with our general understanding of tropical convection.

  3. Characterizing growth patterns in longitudinal MRI using image contrast

    NASA Astrophysics Data System (ADS)

    Vardhan, Avantika; Prastawa, Marcel; Vachet, Clement; Piven, Joseph; Gerig, Guido

    2014-03-01

    Understanding the growth patterns of the early brain is crucial to the study of neuro-development. In the early stages of brain growth, a rapid sequence of biophysical and chemical processes take place. A crucial component of these processes, known as myelination, consists of the formation of a myelin sheath around a nerve fiber, enabling the effective transmission of neural impulses. As the brain undergoes myelination, there is a subsequent change in the contrast between gray matter and white matter as observed in MR scans. In this work, gray-white matter contrast is proposed as an effective measure of appearance which is relatively invariant to location, scanner type, and scanning conditions. To validate this, contrast is computed over various cortical regions for an adult human phantom. MR (Magnetic Resonance) images of the phantom were repeatedly generated using different scanners, and at different locations. Contrast displays less variability over changing conditions of scan compared to intensity-based measures, demonstrating that it is less dependent than intensity on external factors. Additionally, contrast is used to analyze longitudinal MR scans of the early brain, belonging to healthy controls and Down's Syndrome (DS) patients. Kernel regression is used to model subject-specific trajectories of contrast changing with time. Trajectories of contrast changing with time, as well as time-based biomarkers extracted from contrast modeling, show large differences between groups. The preliminary applications of contrast based analysis indicate its future potential to reveal new information not covered by conventional volumetric or deformation-based analysis, particularly for distinguishing between normal and abnormal growth patterns.

  4. Thermal neutron image intensifier tube provides brightly visible radiographic pattern

    NASA Technical Reports Server (NTRS)

    Berger, H.; Kraska, I.; Niklas, W.; Schmidt, A.

    1967-01-01

    Vacuum-type neutron image intensifier tube improves image detection in thermal neutron radiographic inspection. This system converts images to an electron image, and with electron acceleration and demagnification between the input target and output screen, produces a bright image viewed through a closed circuit television system.

  5. Astronomy in the Cloud: Using MapReduce for Image Co-Addition

    NASA Astrophysics Data System (ADS)

    Wiley, K.; Connolly, A.; Gardner, J.; Krughoff, S.; Balazinska, M.; Howe, B.; Kwon, Y.; Bu, Y.

    2011-03-01

    In the coming decade, astronomical surveys of the sky will generate tens of terabytes of images and detect hundreds of millions of sources every night. The study of these sources will involve computation challenges such as anomaly detection and classification and moving-object tracking. Since such studies benefit from the highest-quality data, methods such as image co-addition, i.e., astrometric registration followed by per-pixel summation, will be a critical preprocessing step prior to scientific investigation. With a requirement that these images be analyzed on a nightly basis to identify moving sources such as potentially hazardous asteroids or transient objects such as supernovae, these data streams present many computational challenges. Given the quantity of data involved, the computational load of these problems can only be addressed by distributing the workload over a large number of nodes. However, the high data throughput demanded by these applications may present scalability challenges for certain storage architectures. One scalable data-processing method that has emerged in recent years is MapReduce, and in this article we focus on its popular open-source implementation called Hadoop. In the Hadoop framework, the data are partitioned among storage attached directly to worker nodes, and the processing workload is scheduled in parallel on the nodes that contain the required input data. A further motivation for using Hadoop is that it allows us to exploit cloud computing resources: i.e., platforms where Hadoop is offered as a service. We report on our experience of implementing a scalable image-processing pipeline for the SDSS imaging database using Hadoop. This multiterabyte imaging data set provides a good testbed for algorithm development, since its scope and structure approximate future surveys. First, we describe MapReduce and how we adapted image co-addition to the MapReduce framework. Then we describe a number of optimizations to our basic approach and report experimental results comparing their performance.

  6. Active probing of cloud multiple scattering, optical depth, vertical thickness, and liquid water content using wide-angle imaging LIDAR.

    SciTech Connect

    Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.); Ho, Cheng,

    2002-01-01

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60-degree full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer, and, from there, estimate the volume-averaged liquid water content. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Here we present recent WAIL data oti various clouds and discuss the extension of WAIL to full diurnal monitoring by means of an ultra-narrow magneto-optic atomic line filter for daytime measurements.

  7. Local binary patterns for stromal area removal in histology images

    NASA Astrophysics Data System (ADS)

    Alomari, Raja S.; Ghosh, Subarna; Chaudhary, Vipin; Al-Kadi, Omar

    2012-03-01

    Nuclei counting in epithelial cells is an indication for tumor proliferation rate which is useful to rank tumors and select an appropriate treatment schedule for the patient. However, due to the high interand intra- observer variability in nuclei counting, pathologists seek a deterministic proliferation rate estimate. Histology tissue contains epithelial and stromal cells. However, nuclei counting is clinically restricted to epithelial cells because stromal cells do not become cancerous themselves since they remain genetically normal. Counting nuclei existing within the stromal tissue is one of the major causes of the proliferation rate non-deterministic estimation. Digitally removing stromal tissue will eliminate a major cause in pathologist counting variability and bring the clinical pathologist a major step closer toward a deterministic proliferation rate estimation. To that end, we propose a computer aided diagnosis (CAD) system for eliminating stromal cells from digital histology images based on the local binary patterns, entropy measurement, and statistical analysis. We validate our CAD system on a set of fifty Ki-67-stained histology images. Ki-67-stained histology images are among the clinically approved methods for proliferation rate estimation. To test our CAD system, we prove that the manual proliferation rate estimation performed by the expert pathologist does not change before and after stromal removal. Thus, stromal removal does not affect the expert pathologist estimation clinical decision. Hence, the successful elimination of the stromal area highly reduces the false positive nuclei which are the major confusing cause for the less experienced pathologists and thus accounts for the non-determinism in the proliferation rate estimation. Our experimental setting shows statistical insignificance (paired student t-test shows ? = 0.74) in the manual nuclei counting before and after our automated stromal removal. This means that the clinical decision of the expert pathologist is not affected by our CAD system which is what we want to prove. However, the usage of our CAD system substantially account for the reduced inter- and intra- proliferation rate estimation variability and especially for less-experienced pathologists.

  8. Hyperspectral Reflectance Signatures and Point Clouds for Precision Agriculture by Light Weight Uav Imaging System

    NASA Astrophysics Data System (ADS)

    Honkavaara, E.; Kaivosoja, J.; Mäkynen, J.; Pellikka, I.; Pesonen, L.; Saari, H.; Salo, H.; Hakala, T.; Marklelin, L.; Rosnell, T.

    2012-07-01

    The objective of this investigation was to study the use of a new type of a low-weight unmanned aerial vehicle (UAV) imaging system in the precision agriculture. The system consists of a novel Fabry-Perot interferometer based hyperspectral camera and a high-resolution small-format consumer camera. The sensors provide stereoscopic imagery in a 2D frame-format and they both weigh less than 500 g. A processing chain was developed for the production of high density point clouds and hyperspectral reflectance image mosaics (reflectance signatures), which are used as inputs in the agricultural application. We demonstrate the use of this new technology in the biomass estimation process, which is based on support vector regression machine. It was concluded that the central factors influencing on the accuracy of the estimation process were the quality of the image data, the quality of the image processing and digital surface model generation, and the performance of the regressor. In the wider perspective, our investigation showed that very low-weight, low-cost, hyperspectral, stereoscopic and spectrodirectional 3D UAV-remote sensing is now possible. This cutting edge technology is powerful and cost efficient in time-critical, repetitive and locally operated remote sensing applications.

  9. Multi-provider architecture for cloud outsourcing of medical imaging repositories.

    PubMed

    Godinho, Tiago Marques; Bastião Silva, Luís A; Costa, Carlos; Oliveira, José Luís

    2014-01-01

    Over the last few years, the extended usage of medical imaging procedures has raised the medical community attention towards the optimization of their workflows. More recently, the federation of multiple institutions into a seamless distribution network has brought hope of increased quality healthcare services along with more efficient resource management. As a result, medical institutions are constantly looking for the best infrastructure to deploy their imaging archives. In this scenario, public cloud infrastructures arise as major candidates, as they offer elastic storage space, optimal data availability without great requirements of maintenance costs or IT personnel, in a pay-as-you-go model. However, standard methodologies still do not take full advantage of outsourced archives, namely because their integration with other in-house solutions is troublesome. This document proposes a multi-provider architecture for integration of outsourced archives with in-house PACS resources, taking advantage of foreign providers to store medical imaging studies, without disregarding security. It enables the retrieval of images from multiple archives simultaneously, improving performance, data availability and avoiding the vendor-locking problem. Moreover it enables load balancing and cache techniques. PMID:25160163

  10. Analysis of spatio-temporal brain imaging patterns by Hidden Markov Models and serial MRI images.

    PubMed

    Wang, Ying; Resnick, Susan M; Davatzikos, Christos

    2014-09-01

    Brain changes due to development and maturation, normal aging, or degenerative disease are continuous, gradual, and variable across individuals. To quantify the individual progression of brain changes, we propose a spatio-temporal methodology based on Hidden Markov Models (HMM), and apply it on four-dimensional structural brain magnetic resonance imaging series of older individuals. First, regional brain features are extracted in order to reduce image dimensionality. This process is guided by the objective of the study or the specific imaging patterns whose progression is of interest, for example, the evaluation of Alzheimer-like patterns of brain change in normal individuals. These regional features are used in conjunction with HMMs, which aim to measure the dynamic association between brain structure changes and progressive stages of disease over time. A bagging framework is used to obtain models with good generalization capability, since in practice the number of serial scans is limited. An application of the proposed methodology was to detect individuals with the risk of developing MCI, and therefore it was tested on modeling the progression of brain atrophy patterns in older adults. With HMM models, the state-transition paths corresponding to longitudinal brain changes were constructed from two completely independent datasets, the Alzheimer Disease Neuroimaging Initiative and the Baltimore Longitudinal Study of Aging. The statistical analysis of HMM-state paths among the normal, progressive MCI, and MCI groups indicates that, HMM-state index 1 is likely to be a predictor of the conversion from cognitively normal to MCI, potentially many years before clinical symptoms become measurable. PMID:24706564

  11. Particle image pattern mutual information and uncertainty estimation for particle image velocimetry

    NASA Astrophysics Data System (ADS)

    Xue, Zhenyu; Charonko, John J.; Vlachos, Pavlos P.

    2015-07-01

    In this work we introduce a new measure for particle image velocimetry (PIV) cross-correlation quality and establish analytically its connection to the basic PIV theory. This metric, which we term ‘mutual information’ (MI), can be used to estimate the number of correlated particles and connect to the PIV measurement uncertainty quantification. In PIV the number of particles in common between two consecutive frames forms the basis of the cross-correlation operation that yields the velocity measurement. Since the particle image pattern intensity distribution within each image represents the available signal, the inherent number of common particle pairs between the cross-correlated images, which can be thought of as the amount of mutual information, governs the potential accuracy of the PIV measurement. The number of common particle pairs between the images can be expressed by the product of the image density NI, and the fraction of particles that leave the frame due to in-plane and out-of-plane motion FI and FO, respectively. It has previously been shown that this parameter, NIFIFO, directly relates to the validity of a PIV measurement. However, in real experiments, NIFIFO is unknown and difficult to calculate. Here we propose to overcome this limitation by introducing a new metric (MI), which directly computes the apparent amount of common information contained in the particle patterns of two consecutive images without prior knowledge of the particle field. Both theoretical derivation and experimental results are provided to show that MI and NIFIFO represent the same characteristics of a PIV measurement. Subsequently, MI is used to develop a model for PIV uncertainty estimation. This metric and the corresponding uncertainty model presented herein are applied to both standard and a filtered phase-only (robust phase correlation) correlation methods. These advancements lead to robust uncertainty estimation models, which are tested against both synthetic benchmark data as well as real experimental measurements. For all cases considered here, {{U}68.5} and {{U}95} uncertainties demonstrated coverage factors approximately equal to the theoretically expected values of 68.5% and 95%, which reflect 1? and 2? levels in a normal distribution model respectively.

  12. THOMPSON ET AL.: RAPID SPECTRAL CLOUD SCREENING 1 Rapid spectral cloud screening onboard aircraft and

    E-print Network

    the system onboard the International Space Station (ISS), where it provides factor of two improvements--Imaging Spectroscopy, Lossy Compression, Cloud Screening, Pattern Recognition, Real Time Systems I. INTRODUCTION FUTURE per day [1]. Proposed imaging spectrometers such as HyspIRI [2] or an International Space Station (ISS

  13. Multi-Focus Raw Bayer Pattern Image Fusion for Single-Chip Camera

    NASA Astrophysics Data System (ADS)

    Yang, Bin; Chen, Jibin

    2015-12-01

    In this paper, an efficient patch-based image fusion approach for raw images of single-chip imaging devices incorporated with the Bayer CFA pattern is presented. The multi-source raw Bayer pattern images are firstly parted into half overlapped patches. Then, the patches with maximum clarity measurement defined for raw Bayer pattern image are selected as the fused patches. Next, all the fused local patches are merged with weighted average method in order to reduce the blockness effect of fused raw Bayer pattern image. Finally, the real color fused image is obtained by gradient based demosaicing technology. The multi-source raw Bayer pattern data is fused before demosaicing, so that the multi-sensor system will be more efficient and the artifacts introduced in demosaicing processing do not accumulate in image fusion processing. For comparison, the raw images are also interpolated firstly, and then various image fusion methods are used to get the fused color images. Experimental results show that the proposed algorithm is valid and very effective.

  14. Point cloud generation from aerial image data acquired by a quadrocopter type micro unmanned aerial vehicle and a digital still camera.

    PubMed

    Rosnell, Tomi; Honkavaara, Eija

    2012-01-01

    The objective of this investigation was to develop and investigate methods for point cloud generation by image matching using aerial image data collected by quadrocopter type micro unmanned aerial vehicle (UAV) imaging systems. Automatic generation of high-quality, dense point clouds from digital images by image matching is a recent, cutting-edge step forward in digital photogrammetric technology. The major components of the system for point cloud generation are a UAV imaging system, an image data collection process using high image overlaps, and post-processing with image orientation and point cloud generation. Two post-processing approaches were developed: one of the methods is based on Bae Systems' SOCET SET classical commercial photogrammetric software and another is built using Microsoft(®)'s Photosynth™ service available in the Internet. Empirical testing was carried out in two test areas. Photosynth processing showed that it is possible to orient the images and generate point clouds fully automatically without any a priori orientation information or interactive work. The photogrammetric processing line provided dense and accurate point clouds that followed the theoretical principles of photogrammetry, but also some artifacts were detected. The point clouds from the Photosynth processing were sparser and noisier, which is to a large extent due to the fact that the method is not optimized for dense point cloud generation. Careful photogrammetric processing with self-calibration is required to achieve the highest accuracy. Our results demonstrate the high performance potential of the approach and that with rigorous processing it is possible to reach results that are consistent with theory. We also point out several further research topics. Based on theoretical and empirical results, we give recommendations for properties of imaging sensor, data collection and processing of UAV image data to ensure accurate point cloud generation. PMID:22368479

  15. Displacement fields from point cloud data: Application of particle imaging velocimetry to landslide geodesy

    NASA Astrophysics Data System (ADS)

    Aryal, Arjun; Brooks, Benjamin A.; Reid, Mark E.; Bawden, Gerald W.; Pawlak, Geno R.

    2012-03-01

    Acquiring spatially continuous ground-surface displacement fields from Terrestrial Laser Scanners (TLS) will allow better understanding of the physical processes governing landslide motion at detailed spatial and temporal scales. Problems arise, however, when estimating continuous displacement fields from TLS point-clouds because reflecting points from sequential scans of moving ground are not defined uniquely, thus repeat TLS surveys typically do not track individual reflectors. Here, we implemented the cross-correlation-based Particle Image Velocimetry (PIV) method to derive a surface deformation field using TLS point-cloud data. We estimated associated errors using the shape of the cross-correlation function and tested the method's performance with synthetic displacements applied to a TLS point cloud. We applied the method to the toe of the episodically active Cleveland Corral Landslide in northern California using TLS data acquired in June 2005-January 2007 and January-May 2010. Estimated displacements ranged from decimeters to several meters and they agreed well with independent measurements at better than 9% root mean squared (RMS) error. For each of the time periods, the method provided a smooth, nearly continuous displacement field that coincides with independently mapped boundaries of the slide and permits further kinematic and mechanical inference. For the 2010 data set, for instance, the PIV-derived displacement field identified a diffuse zone of displacement that preceded by over a month the development of a new lateral shear zone. Additionally, the upslope and downslope displacement gradients delineated by the dense PIV field elucidated the non-rigid behavior of the slide.

  16. Universal image coding using multiscale recurrent patterns and prediction

    Microsoft Academic Search

    Nuno M. M. Rodrigues; Eduardo A. B. Da Silva; Murilo B. De Carvalho; Sérgio M. M. De Faria; Vítor Manuel Mendes Da Silva

    2005-01-01

    In this paper we present a new method for image coding that is able to achieve good results over a wide range of image types. This work is based on the Multidimensional Multiscale Parser (MMP) algorithm (1), allied with an in- tra frame image predictive coding scheme. MMP has been shown to have, for a large class of image data,

  17. Statistical image recovery from laser speckle patterns with polarization diversity

    Microsoft Academic Search

    Donald B. Dixon

    2010-01-01

    This research extends the theory and understanding of the laser speckle imaging technique. This non-traditional imaging technique may be employed to improve space situational awareness and image deep space objects from a ground-based sensor system. The use of this technique is motivated by the ability to overcome aperture size limitations and the distortion effects from Earth's atmosphere. Laser speckle imaging

  18. Pattern Recognition Software and Techniques for Biological Image Analysis

    Microsoft Academic Search

    Lior Shamir; John D. Delaney; Nikita Orlov; D. Mark Eckley; Ilya G. Goldberg

    2010-01-01

    The increasing prevalence of automated image acquisition systems is enabling new types of microscopy experiments that generate large image datasets. However, there is a perceived lack of robust image analysis systems required to process these diverse datasets. Most automated image analysis systems are tailored for specific types of microscopy, contrast methods, probes, and even cell types. This imposes significant constraints

  19. Compressed Pattern Matching for Predictive Lossless Image Encoding School of EECS

    E-print Network

    Mukherjee, Amar

    work, we studied the most three popular lossless image compression schemes: lossless JPEG, CALICCompressed Pattern Matching for Predictive Lossless Image Encoding Tao Tao School of EECS topic in computer science. Most works have been done in CPM are for text or for lossy compressed image

  20. New Image Retrieval System Based on Robust Color and Texture Pattern Feature Extractions

    Microsoft Academic Search

    Zhuo Liu; Shigeo Wada

    2006-01-01

    In this dissertation, a new image retrieval system based on robust color and texture pattern feature extractions is investigated. The substance of research is composed of three main parts. First, robust feature extraction method from an original image based on advanced image processing techniques is proposed. The robustness designates geometric distortions (rotation, scaling and translation), illumination degradation and additive noise.

  1. Quantitative super-resolution imaging uncovers reactivity patterns on single nanocatalysts

    E-print Network

    Chen, Peng

    Quantitative super-resolution imaging uncovers reactivity patterns on single nanocatalysts Xiaochunc, Supplementary Figs S5­S10 and Scheme S1). We used a super-resolution imaging approach to study, as individual nanocatalysts can differ greatly9,12­18 . Our super-resolution imaging of catalytic reactions

  2. J. Marti et al. (Eds.): Pattern Recognition and Image Analysis, LNCS 4477, 386393, 2007.

    E-print Network

    J. Mart´i et al. (Eds.): Pattern Recognition and Image Analysis, LNCS 4477, 386­393, 2007. c Springer-Verlag Berlin Heidelberg 2007 Variational Deconvolution of Multi-Channel Images with Inequality Constraints Martin Welk1 and James G. Nagy2 1 Mathematical Image Analysis Group Faculty of Mathematics

  3. Assessing the performance of the Lightning Imaging Sensor (LIS) using Deep Convective Clouds

    NASA Astrophysics Data System (ADS)

    Buechler, Dennis E.; Koshak, William J.; Christian, Hugh J.; Goodman, Steven J.

    2014-01-01

    The stability of the LIS instrument is examined during a 13 year period (1998-2010) by examining LIS background radiance observations of Deep Convective Clouds (DCCs) which are identified by their cold IR brightness temperature. Pixels in the LIS background image associated with DCCs are identified and analyzed during July and August of each year in the 13 year period. The resulting LIS DCC radiances are found to be stable throughout the period, varying at most by 0.8% from the 13 year mean July August value of 358.1 W sr- 1 m- 2 ?m- 1. The DCC method in this study provides a good approach for evaluating the stability of the future GOES-R Geostationary Lightning Mapper (GLM).

  4. Remote sensing of cloud, aerosol and water vapor properties from the Moderate Resolution Imaging Spectrometer (MODIS)

    NASA Technical Reports Server (NTRS)

    King, M. D.

    1992-01-01

    The Moderate Resolution Imaging Spectrometer (MODIS) is an Earth-viewing sensor being developed as a facility instrument for the Earth Observing System (EOS) to be launched in the late 1990s. MODIS consists of two separate instruments that scan a swath width sufficient to provide nearly complete global coverage every two days from a polar-orbiting, Sun-synchronous, platform at an altitude of 705 km. Of primary interest for studies of atmospheric physics is the MODIS-N (nadir) instrument which will provide images in 36 spectral bands between 0.415 and 14.235 micrometers with spatial resoulutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean and atmosperhic processes. The intent of this lecture is to describe the current status of MODIS-N and its companion instrument MODIS-T (tilt), a tiltable cross-track scanning radiometer with 32 uniformly spaced channels between 0.410 and 0.875 micrometers, and to describe the physical principles behind the development of MODIS for the remote sensing of atmospheric properties. Primary emphasis will be placed on the main atmospheric applications of determining the optical, microphysical and physical properties of clouds and aerosol particles form spectral-reflection and thermal-emission measurements. In addition to cloud and aerosol properties, MODIS-N will be utilized for the determination of the total precipitable water vapor over land and atmospheric stability. The physical principles behind the determination of each of these atmospheric products will be described herein.

  5. Types of Clouds

    NSDL National Science Digital Library

    Duane Friend

    This is a basic lesson on clouds. Very nice photos of cumulus and cumulonimbus clouds are presented on the page as well as a description of all major cloud types and their associated weather. Two activities are presented. One invites the learner to create a cloud, while the other involves creating a collage of cloud images along with information about the weather associated with each cloud type.

  6. Image-based correlation of Laser Scanning point cloud time series for landslide monitoring

    NASA Astrophysics Data System (ADS)

    Travelletti, Julien; Malet, Jean-Philippe; Delacourt, Christophe

    2014-10-01

    Very high resolution monitoring of landslide kinematics is an important aspect for a physical understanding of the failure mechanisms and for quantifying the associated hazard. In the last decade, the potential of Terrestrial Laser Scanning (TLS) to monitor slow-moving landslides has been largely demonstrated but accurate processing methods are still needed to extract useful information available in point cloud time series. This work presents an approach to measure the 3D deformation and displacement patterns from repeated TLS surveys. The method is based on the simplification of a 3D matching problem in a 2D matching problem by using a 2D statistical normalized cross-correlation function. The computed displacement amplitudes are compared to displacements (1) calculated with the classical approach of Iterative Closest Point and (2) measured from repeated dGPS observations. The performance of the method is tested on a 3 years dataset acquired at the Super-Sauze landslide (South French Alps). The observed landslide displacements are heterogeneous in time and space. Within the landslide, sub-areas presenting different deformation patterns (extension, compression) are detected by a strain analysis. It is demonstrated that pore water pressure changes within the landslide is the main controlling factor of the kinematics.

  7. Cloud Games

    NSDL National Science Digital Library

    University Corporation for Atmospheric Research - Education and Outreach Programs

    2010-01-01

    Play these two matching games from the Web Weather for Kids site to pair cloud images with their names/types! Developed by the University Corporation for Atmospheric Research, this site requires Java.

  8. PSC Meteorology Program Cloud Boutique

    NSDL National Science Digital Library

    Plymouth State College (PSC) provides the PSC Meteorology Program Cloud Boutique Website to "provide explanations of and access to detailed pictures of some basic cloud forms." Spectacular images and brief descriptions of high clouds (cirrus, cirrocumulus, and cirrostratus), middle clouds (altocumulus and altostratus), low clouds (cumulus, stratocumulus, stratus, and fog), multi-layer clouds (nimbostratus and cumulonimbus), and orographic clouds (lenticular and cap), among others are included. The site is an excellent general cloud reference.

  9. The 2009-2010 fade of Jupiter's South Equatorial Belt: Vertical cloud structure models and zonal winds from visible imaging

    NASA Astrophysics Data System (ADS)

    Pérez-Hoyos, S.; Sanz-Requena, J. F.; Barrado-Izagirre, N.; Rojas, J. F.; Sánchez-Lavega, A.; IOPW Team

    2012-01-01

    The South Equatorial Belt (SEB) of Jupiter is known to alternate its appearance at visible wavelengths from a classical belt-like band most of the time to a short-lived zone-like aspect which is called a "fade" of the belt, hereafter SEBF. The albedo change of the SEB is due to a change in the structure and properties of the clouds and upper hazes. Recent works based on infrared observations of the last SEBF have shown that the aerosol density below 1 bar increased in parallel with the reflectivity change. However, the nature of the change in the upper clouds and hazes that produces the visible reflectivity change and whether or not this reflectivity change is accompanied by a change in the winds at the upper cloud level remained unknown. In this paper we focus in the near ultraviolet to near infrared reflected sunlight (255-953 nm) to address these two issues. We characterize the vertical cloud structure above the ammonia condensation level from Hubble Space Telescope images, and the zonal wind velocities from long-term high-quality images coming from the International Outer Planet Watch database, both during the SEB and SEBF phases. We show that reflectivity changes do not happen simultaneously in this wavelength range, but they start earlier in the most deep-sensing filters and end in 2010 with just minor changes in those sensing the highest particle layers. Our models require a substantial increase of the optical thickness of the cloud deck at 1.0 ± 0.4 bar from ? cloud = 6 ± 2 in July 2009 (SEB phase) to semiinfinite at visual wavelengths in 2010 (SEBF). Upper tropospheric particles (˜240-1400 mbar) are also required to become substantially reflectant and their single scattering albedo in the blue changes from ?0 = 0.905 ± 0.005 in November 2009 to ?0 = 0.95 ± 0.01 in June 2010. No significant changes were found in the cloud top heights or in the particle density of the tropospheric haze. The disturbance travels from the levels below ˜3 bar to a level about 400 ± 100 mbar. We derive an upward velocity of 0.15 ± 0.05 cm/s, in agreement with a diffusive process in Jupiter's upper troposphere requiring a mean eddy coefficient K ˜ 8 × 10 5 cm 2 s -1. On the other hand, cloud tracking on the IOPW imaging showed no significant changes in the zonal wind profile between the SEB and SEBF stages. As in other visually huge changes in Jupiter's cloud morphology and structure, the wind profile remains robust, possibly indicating a deeply rooted dynamical regime.

  10. Pixel patterns for voxels in a contact-type three-dimensional imaging system for full-parallax image display

    SciTech Connect

    Son, Jung-Young; Saveljev, Vladmir V.; Javidi, Bahram; Kim, Dae-Sik; Park, Min-Chul

    2006-06-20

    Incomplete voxels, which can be seen only at a part of the viewing zone's cross section in the optical configuration of a full parallax multiview imaging system based on a two-dimensional point light source array, are identified. Their corresponding pixel patterns are found to maximize the space where the voxels can exist in the configuration and to increase the voxel resolution of the displayable three-dimensional images. Furthermore, the pixel patterns for the rhomb-shaped pixel cells are also defined, and some problems related to voxel-based image synthesis are discussed.

  11. Multi-Scale Fractal Analysis of Image Texture and Pattern

    NASA Technical Reports Server (NTRS)

    Emerson, Charles W.; Lam, Nina Siu-Ngan; Quattrochi, Dale A.

    1999-01-01

    Analyses of the fractal dimension of Normalized Difference Vegetation Index (NDVI) images of homogeneous land covers near Huntsville, Alabama revealed that the fractal dimension of an image of an agricultural land cover indicates greater complexity as pixel size increases, a forested land cover gradually grows smoother, and an urban image remains roughly self-similar over the range of pixel sizes analyzed (10 to 80 meters). A similar analysis of Landsat Thematic Mapper images of the East Humboldt Range in Nevada taken four months apart show a more complex relation between pixel size and fractal dimension. The major visible difference between the spring and late summer NDVI images of the absence of high elevation snow cover in the summer image. This change significantly alters the relation between fractal dimension and pixel size. The slope of the fractal dimensional-resolution relation provides indications of how image classification or feature identification will be affected by changes in sensor spatial resolution.

  12. Multi-Scale Fractal Analysis of Image Texture and Pattern

    NASA Technical Reports Server (NTRS)

    Emerson, Charles W.; Lam, Nina Siu-Ngan; Quattrochi, Dale A.

    1999-01-01

    Analyses of the fractal dimension of Normalized Difference Vegetation Index (NDVI) images of homogeneous land covers near Huntsville, Alabama revealed that the fractal dimension of an image of an agricultural land cover indicates greater complexity as pixel size increases, a forested land cover gradually grows smoother, and an urban image remains roughly self-similar over the range of pixel sizes analyzed (10 to 80 meters). A similar analysis of Landsat Thematic Mapper images of the East Humboldt Range in Nevada taken four months apart show a more complex relation between pixel size and fractal dimension. The major visible difference between the spring and late summer NDVI images is the absence of high elevation snow cover in the summer image. This change significantly alters the relation between fractal dimension and pixel size. The slope of the fractal dimension-resolution relation provides indications of how image classification or feature identification will be affected by changes in sensor spatial resolution.

  13. Cips (Cloud Imaging and Particle Size Experiment) Observations of a Newly Discovered Population of Very Large Ice Particles in Polar Mesospheric Clouds

    NASA Astrophysics Data System (ADS)

    Rusch, D. W.; Thomas, G. E.; Chandran, A.; Merkel, A. W.; Lumpe, J. D., Jr.; Randall, C. E.; Olivero, J. J.; Bailey, S. M.; Russell, J. M., III

    2014-12-01

    Observations by the Cloud Imaging and Particle Size (CIPS) instrument on the Aeronomy of Ice in the Mesosphere (AIM) satellite have demonstrated the existence of Polar Mesospheric Cloud (PMC) regions populated by particles in the size range between 60 and 100 nm (radii of equivalent volume spheres). It is known from lidar, SOFIE, and CIPS measurements that typical mean PMC particle sizes are of the order of 40-50 nm. Determination of particle sizes by CIPS is accomplished by measuring the scattering of solar radiation at various scattering angles at a spatial resolution of 25 km2. PMC with ice particles principally in this 60-100 nm range are observed in 15 to 20 % of all CIPS measurements. These very large particle (VLP) events occur over spatially coherent areas. They are generally associated with regions of low cloud albedo (brightness) and ice water content. We postulate that at least part of this VLP population exists due to the action of long-period gravity waves in the low-temperature summertime mesopause region. We demonstrate the proposed mechanism through use of the 2D Community Aerosol and Radiation Model for Atmospheres (CARMA), which simulates the evolution of ice particles over several cycles of a family of modeled gravity waves. The model results are consistent with a VLP population in the cold troughs of monochromatic gravity waves with horizontal wavelengths of 600 km and periods of 10 hours (Chandran et al., 2013).

  14. Imaging Use and Cryptorchidism: Determinants of Practice Patterns

    PubMed Central

    Tasian, Gregory E.; Yiee, Jenny H.; Copp, Hillary L.

    2014-01-01

    Purpose We determined the rate of diagnostic imaging use for the preoperative evaluation of boys with cryptorchidism and the factors that influence referring providers to obtain imaging. Materials and Methods We conducted a national cross-sectional survey of pediatricians randomly sampled from the American Medical Association Physician Masterfile. The primary outcome was whether the respondent obtained imaging at the initial evaluation of boys with cryptorchidism. Participants were queried regarding practice location and type, length of time in practice, frequency of reading academic journals and the accessibility of surgical sub-specialists. For those who ordered imaging, respondents were asked how frequently they ordered imaging, and were asked to select patient factors and professional beliefs that influenced their decision to obtain imaging. Factors associated with imaging use were identified using multivariate logistic regression. Results Of the pediatricians who acknowledged contact by surveyors 47% completed the survey and 34% of respondents reported always or usually ordering imaging. Of those who obtained imaging 96.4% used ultrasound. Pediatricians in practice fewer than 20 years (OR 3.43, 95% CI 1.92–6.16) and those in nonacademic practices (OR 3.00, 95% CI 1.34 – 6.71) were more likely to order imaging. Pediatricians obtained imaging because of beliefs that imaging reliably identifies a nonpalpable testis, reassures the family and assists the surgeon with operative planning. Conclusions Ultrasound is heavily used by pediatricians for the preoperative evaluation of cryptorchidism, especially when the testis is nonpalpable. Given the poor diagnostic performance of ultrasound in this setting, we recommend developing strategies to reduce imaging use in cryptorchidism. PMID:21421239

  15. Adaption of Archetype Patterns for mobile cloud-based business apps

    Microsoft Academic Search

    Sebastian Damm; Thomas Ritz; Jakob Strauch

    2011-01-01

    The creating of reusable mobile solutions is influenced by many factors. The platforms are arbitrary, the target audience can be new to mobile software, and the devices are not always online and restricted in their computational capabilities. This paper presents an archetype pattern- and REST-driven approach for building customizable, flexible, and efficient mobile business applications. Furthermore, offline scenarios will be

  16. Proceedings of the NASA Symposium on Mathematical Pattern Recognition and Image Analysis

    NASA Technical Reports Server (NTRS)

    Guseman, L. F., Jr.

    1983-01-01

    The application of mathematical and statistical analyses techniques to imagery obtained by remote sensors is described by Principal Investigators. Scene-to-map registration, geometric rectification, and image matching are among the pattern recognition aspects discussed.

  17. The Seasonal and Diurnal Patterns of net Ecosystem CO2 Exchange in a Subtropical Montane Cloud Forest.

    NASA Astrophysics Data System (ADS)

    Chu, H.; Lai, C.; Wu, C.; Hsia, Y.

    2008-12-01

    CO2 fluxes were measured by an open/closed path eddy covariance system at a natural regenerated 50-years-old yellow cypress (Chamaecyparis obtusa var. formosana) forest at Chi-Lan Mountain site (CLM site, 24°35'N, 121°25'E, 1650 m elevation), north-eastern Taiwan. CLM site is located at a relative uniform south-eastern-facing valley slope (15°) characterized with year round fog occurrence and diurnal mountain-valley wind and can be classified as subtropical montane cloud forest. Based on measurement from July 2007 to June 2008, seasonal and diurnal patterns of CO2 fluxes were described and patterns under different cloudiness and foggy conditions were presented. Comparing with other cypress forests in temperate region, there is only a weak seasonal pattern of the CO2 fluxes at CLM site. Throughout the year, average incident photosynthetically active radiation in summer was almost the double of that in winter, whereas the difference of mean daytime CO2 fluxes among seasons was much less than the seasonal light difference. During summer when light intensity was higher, mean daytime CO2 fluxes reached -7.5 ?mol/m2/s in July and -8.8 ?mol/m2/s in August. As heavy fog accounted for 64% and 67% of the time in November and February, mean daytime CO2 fluxes dropped to -6.9 and -6.1 ?mol/m2/s respectively. With comparable higher incident radiation intensity (>1000 ?mol/m2/s), the CO2 fluxes were higher in overcast days than in clear days. In July 2007, clear days accounted for 30% of the month, light intensity reached its peak at midday, and however, CO2 fluxes didn't reach its highest value in the meanwhile. Canopy conductance calculated from the Penman-Monteith equation and measured latent heat fluxes both showed a midday depression at clear days, which indicated the regulation of transpiration by plant physiological mechanism. With comparable lower incident radiation intensity (<1000 ?mol/m2/s), the CO2 fluxes were higher in overcast days than in foggy days. The difference suggested that water droplets deposited on leaves might partially block the pathway of the gas exchange through stomata as canopy immersed in the very humid air. However, CO2 fluxes did not cease during foggy periods, as also supported by sap flow and leaf chamber measurements, the morphological characteristics of leaf or/and canopy structure might contribute to the well adaptability of this subtropical montane cloud forest to the humid environment.

  18. Basic research planning in mathematical pattern recognition and image analysis

    NASA Technical Reports Server (NTRS)

    Bryant, J.; Guseman, L. F., Jr.

    1981-01-01

    Fundamental problems encountered while attempting to develop automated techniques for applications of remote sensing are discussed under the following categories: (1) geometric and radiometric preprocessing; (2) spatial, spectral, temporal, syntactic, and ancillary digital image representation; (3) image partitioning, proportion estimation, and error models in object scene interference; (4) parallel processing and image data structures; and (5) continuing studies in polarization; computer architectures and parallel processing; and the applicability of "expert systems" to interactive analysis.

  19. A Quantitative Evaluation of Fixed-Pattern Noise Reduction Methods in Imaging Systems

    Microsoft Academic Search

    Pablo Meza; César San Martín; Esteban Vera; Sergio N. Torres

    2010-01-01

    \\u000a Fixed-pattern noise is a common feature in several uncalibrated imaging systems, and it typically appears as striping and\\u000a grid-like nonuniformity artifacts in hyperspectral and infrared cameras. In this work, we present a quantitative and comparative\\u000a analysis of fixed-pattern noise reduction, or calibrating techniques, by using several image quality indexes. A special emphasis\\u000a is made in demonstrating the correspondence between the

  20. Underwater mine detection using symbolic pattern analysis of sidescan sonar images

    Microsoft Academic Search

    Chinmay Rao; Kushal Mukherjee; Shalabh Gupta; Asok Ray; Shashi Phoha

    2009-01-01

    This paper presents symbolic pattern analysis of sidescan sonar images for detection of mines and mine-like objects in the underwater environment. For robust feature extraction, sonar images are symbolized by partitioning the data sets based on the information generated from the ground truth. A binary classifier is constructed for identification of detected objects into mine-like and non-mine-like categories. The pattern

  1. The large contour data generation from divided image of photomask pattern of 32 nm and beyond

    Microsoft Academic Search

    Tsutomu Murakawa; Yoshiaki Ogiso; Toshimichi Iwai; Jun Matsumoto; Takayuki Nakamura

    2010-01-01

    The application of Mask CD-SEM for process management of photomask using two dimensional measurements as photomask patterns become smaller and more complex, [1]. Also, WPI technology application using an optical Mask inspection tool simulates wafer plane images using photomask images [2]. In order to simulate the MEEF influence for aggressive OPC and High-end photomask patterns in 32nm node and beyond,

  2. Visual simulation of clouds

    Microsoft Academic Search

    Geoffrey Y. Gardner

    1985-01-01

    Clouds present serious problems to standard computer image generation techniques because clouds do not have well-defined surfaces and boundaries. In addition, clouds contain varying degrees of translucence, and their amorphous structure can change with time. Although several approaches to cloud simulation have produced impressive results, they have relied on complex mathematical models which produce high computation costs for a single

  3. Image-level and group-level models for Drosophila gene expression pattern annotation

    PubMed Central

    2013-01-01

    Background Drosophila melanogaster has been established as a model organism for investigating the developmental gene interactions. The spatio-temporal gene expression patterns of Drosophila melanogaster can be visualized by in situ hybridization and documented as digital images. Automated and efficient tools for analyzing these expression images will provide biological insights into the gene functions, interactions, and networks. To facilitate pattern recognition and comparison, many web-based resources have been created to conduct comparative analysis based on the body part keywords and the associated images. With the fast accumulation of images from high-throughput techniques, manual inspection of images will impose a serious impediment on the pace of biological discovery. It is thus imperative to design an automated system for efficient image annotation and comparison. Results We present a computational framework to perform anatomical keywords annotation for Drosophila gene expression images. The spatial sparse coding approach is used to represent local patches of images in comparison with the well-known bag-of-words (BoW) method. Three pooling functions including max pooling, average pooling and Sqrt (square root of mean squared statistics) pooling are employed to transform the sparse codes to image features. Based on the constructed features, we develop both an image-level scheme and a group-level scheme to tackle the key challenges in annotating Drosophila gene expression pattern images automatically. To deal with the imbalanced data distribution inherent in image annotation tasks, the undersampling method is applied together with majority vote. Results on Drosophila embryonic expression pattern images verify the efficacy of our approach. Conclusion In our experiment, the three pooling functions perform comparably well in feature dimension reduction. The undersampling with majority vote is shown to be effective in tackling the problem of imbalanced data. Moreover, combining sparse coding and image-level scheme leads to consistent performance improvement in keywords annotation. PMID:24299119

  4. Contrast of time-averaged image speckle pattern for a vibrating object

    Microsoft Academic Search

    N. Takai

    1978-01-01

    In vibration analysis by speckle photography it is qualitatively known that the contrast of speckle patterns averaged in the exposure time varies, depending on the object motion. In this paper, the contrast of time-averaged image speckle patterns is theoretically evaluated and found to be determined by the ratio of the sinusoidally oscillating amplitude of the object motion to the average

  5. Imaging the outward motions of clumpy dust clouds around the red supergiant Antares with VLT/VISIR

    NASA Astrophysics Data System (ADS)

    Ohnaka, K.

    2014-08-01

    Aims: We present a 0."5-resolution 17.7 ?m image of the red supergiant Antares. Our aim is to study the structure of the circumstellar envelope in detail. Methods: Antares was observed at 17.7 ?m with the VLT mid-infrared instrument VISIR. Taking advantage of the BURST mode, in which a large number of short exposure frames are taken, we obtained a diffraction-limited image with a spatial resolution of 0."5. Results: The VISIR image shows six clumpy dust clouds located at 0."8-1."8 (43-96 R? = 136-306 AU) away from the star. We also detected compact emission within a radius of 0."5 around the star. Comparison of our VISIR image taken in 2010 and the 20.8 ?m image taken in 1998 with the Keck Telescope reveals the outward motions of four dust clumps. The proper motions of these dust clumps (with respect to the central star) amount to 0."2-0."6 in 12 years. This translates into expansion velocities (projected onto the plane of the sky) of 13-40 km s-1 with an uncertainty of ± 7 km s-1. The inner compact emission seen in the 2010 VISIR image is presumably newly formed dust, because it is not detected in the image taken in 1998. If we assume that the dust is ejected in 1998, the expansion velocity is estimated to be 34 km s-1, in agreement with the velocity of the outward motions of the clumpy dust clouds. The mass of the dust clouds is estimated to be (3-6) × 10-9 M?. These values are lower by a factor of 3-7 than the amount of dust ejected in one year estimated from the (gas+dust) mass-loss rate of 2 × 10-6 M? yr-1, suggesting that the continuous mass loss is superimposed on the clumpy dust cloud ejection. Conclusions: The clumpy dust envelope detected in the 17.7 ?m diffraction-limited image is similar to the clumpy or asymmetric circumstellar environment of other red supergiants. The velocities of the dust clumps cannot be explained by a simple accelerating outflow, implying the possible random nature of the dust cloud ejection mechanism. Based on VISIR observations made with the Very Large Telescope of the European Southern Observatory. Program ID: 385.D-0120(A), 286.D-5007(A).

  6. Tiros III cloud distributions and vorticity patterns over the southeastern United States and adjacent water area

    E-print Network

    Abbott, Graham Ellis

    1963-01-01

    surfaces to those whose cross sections are elliptic, hyperbolic, parabolic, circular, or linear. At this point, having now determined the necessary height values, computations were continued to determine values of relative vorticity, absolute vorticity...-mb trough, located gust to the west of the Appalachian Mountain chain, had a tendency to rotate from a NNE-SSW orientation to a N-S position, with a slight westward movement during this 24-hr period. The 300-mb con- tour patterns indicate...

  7. Image enhancement for pattern recognition Quyen Huynha;b

    E-print Network

    Intrator, Nathan

    the denoised (reconstructed) image from the rst level. Again, we used Coi et-5 and Symmlet-8 mother wavelets excellent results on these data. We start by investigating various wavelet and wavelet packet denoising in signal and image denoising. We notice that the performance is mostly a ected by the choice of the scale

  8. Image data compression-encryption using G-scan patterns

    Microsoft Academic Search

    Nikolaos G. Bourbakis

    1997-01-01

    This paper presents an efficient image compression-encryption methodology by using fractals. The methodology is based on the principles and ideas reflected by the family of fractal based languages (Scan) and is mainly motivated for the compression and encryption of 2D digital images. Scan represents a family of special purpose context free languages which access sequentially or process the nxn data

  9. Damage Pattern Mining in Hurricane Image Shu-Ching Chen1

    E-print Network

    Chen, Shu-Ching

    of Hurricane Andrew in 1992 are conducted and ana- lyzed to show the effectiveness of the proposed Hurricane, segmentation, QBE (Query c 2003 IEEE. By Image). 1 Introduction After Hurricane Andrew in 1992, many areasDamage Pattern Mining in Hurricane Image Databases Shu-Ching Chen1 , Mei-Ling Shyu2 , Chengcui

  10. A 128128 Floating Gate Imager with Self-Adapting Fixed Pattern Noise Reduction

    E-print Network

    Maryland at College Park, University of

    A 128×128 Floating Gate Imager with Self-Adapting Fixed Pattern Noise Reduction Yanyi Liu Wong-mode imager that uses nonvolatile floating gate charge storage in the pixel for automatic cancellation charge on a floating gate in each pixel. The floating gate technique has long been used for adaptation

  11. Images of the Floating World: Drainage Patterns in Thinning Soap Films

    E-print Network

    Troian, Sandra M.

    Images of the Floating World: Drainage Patterns in Thinning Soap Films Submitted by S. Berg, E. A to right a dendritic instability e : magnified and enhanced image of d , which advances as a fractal front floating plumes. The authors gratefully acknowledge support from the NSF, NASA, and Unilever Research US. 1

  12. Genetic Algorithm-Based Relevance Feedback for Image Retrieval Using Local Similarity Patterns.

    ERIC Educational Resources Information Center

    Stejic, Zoran; Takama, Yasufumi; Hirota, Kaoru

    2003-01-01

    Proposes local similarity pattern (LSP) as a new method for computing digital image similarity. Topics include optimizing similarity computation based on genetic algorithm; relevance feedback; and an evaluation of LSP on five databases that showed an increase in retrieval precision over other methods for computing image similarity. (Author/LRW)

  13. Human Perception of Fixed Pattern Noise in Pyramidal CMOS Image Sensor

    E-print Network

    Hornsey, Richard

    -performance CMOS active pixel sensors (APS) image sensor are attracting more and more interest thanksHuman Perception of Fixed Pattern Noise in Pyramidal CMOS Image Sensor Fayçal Saffih*a , Richard I Street, Toronto, ON, CANADA M3J 1P3 ABSTRACT We demonstrate a non-orthogonal architecture for a CMOS

  14. Automated tissue segmentation and blind recovery H MRS imaging spectral patterns of normal

    E-print Network

    Sajda, Paul

    INTRODUCTION In vivo single-voxel 1 H MRS (1,2) and its multi-voxel metabolic imaging counterpart, 1 H MRSI (3,8). For such large multi-planar 1 H MRSI data sets, availability of a data analysis method that can quickly recoverAutomated tissue segmentation and blind recovery of 1 H MRS imaging spectral patterns of normal

  15. Accuracy of mask pattern contour extraction with fine-pixel SEM images

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Shinji; Yamanaka, Eiji; Mukai, Hidefumi; Kotani, Toshiya; Mashita, Hiromitsu; Itoh, Masamitsu

    2007-10-01

    The specification of photomask patterns is defined for each semiconductor device technology node based on the ITRS (International Technology Roadmap for Semiconductors). The quality of the photomask patterns has been managed by using a metrology tool for CD (Critical Dimension) and an inspection tool for pattern shape. According to shrinkage of semiconductor device patterns, the lithography margin has gradually become smaller. Consequently, the quality of photomask patterns has been managed by observing small lithography margin patterns in addition to the conventional quality management patterns with the conventional metrology tool. Furthermore, recently, as each successive device generation has become shorter, rapid improvement of not only turnaround time of photomask manufacturing but also yield of semiconductor device manufacturing has become necessary. Therefore, the importance of the flexible mask specifications concept is increasing. The quality of photomask patterns with respect to the specifications is judged in terms of pass/fail based on the allowable lithography margin. The methodology is that small lithography margin patterns are selected, micrographs of the selected photomask patterns are acquired by a metrology tool, photomask pattern contours are extracted with the micrographs, resist patterns exposed on Si wafer are simulated by using the photomask pattern contours with lithography simulation under actual exposure conditions, the lithography margin is calculated and the quality of the photomask is judged in terms of pass/fail criteria based on the lithography margin for each generation, device and layer. For management of the quality of photomask patterns based on the flexible mask specifications, it is necessary to measure two-dimensional patterns such as hot-spot patterns for each critical layer in devices having small lithography margin. Therefore, in order to manage quality in the case of flexible mask specifications, a two-dimensional photomask pattern contour extraction tool was studied and developed. The photomask pattern contour extraction tool realizes the combination of acquisition of fine-pixel SEM images of the photomask patterns in wide field and extraction of photomask pattern contours by using the acquired fine-pixel SEM images. There have been many reports on the repeatability and reliability of CD and two-dimensional pattern metrology tools based on the conventional specifications. However, there are very few reports on the repeatability and reliability of photomask pattern metrology tools based on flexible mask specifications. In this paper, using small lithography margin patterns, firstly, the fine-pixel SEM images of photomask patterns are acquired. Secondly, contours of the photomask patterns are extracted with the SEM images. Thirdly, contours of resist patterns on Si wafer are simulated with lithography simulation under actual exposure condition by using the actual photomask pattern contours. Finally, the lithography margin is calculated by using FEM (Focus Exposure Matrix) for the simulated contours of resist patterns. This flow is repeated. The lithography margin with this flow is compared with that of actual exposed wafers. Repeatability and reliability of the lithography margin is evaluated. As a result, accuracy of the photomask pattern contour extraction tool is discussed.

  16. Sano's capillary pattern classification for narrow-band imaging of early colorectal lesions.

    PubMed

    Uraoka, Toshio; Saito, Yutaka; Ikematsu, Hiroaki; Yamamoto, Kazuhide; Sano, Yasushi

    2011-05-01

    Narrow-band imaging enhances visualization of the mucosal surface structure and vascular network and helps to increase the visibility of neoplasia by improving contrast. Sano and his colleagues first reported its efficacy for endoscopic use in the gastrointestinal tract and later proposed a sequential classification of the mucosal vascular network patterns according to histopathological categories. Sano's 'capillary pattern classification' was established to facilitate diagnosis of early colorectal lesions on a step-by-step basis. This review focuses on the utility and effectiveness of Sano's capillary pattern classification when examining early colorectal lesions using narrow-band imaging. PMID:21535215

  17. Phase retrieval from single frame projection fringe pattern with variational image decomposition

    NASA Astrophysics Data System (ADS)

    Zhu, Xinjun; Tang, Chen; Li, Biyuan; Sun, Chen; Wang, Linlin

    2014-08-01

    Phase retrieval from single frame projection fringe pattern is of fundamental importance, and is also a challenging problem in fringe projection measurement. In this paper, we present a new method for phase retrieval from a single frame projection fringe pattern based on variational image decomposition (VID) methods. We propose a new image decomposition model TV-G-Shearlet in order to effectively split a projection fringe pattern into background part, fringe part and noise part. The performance of the proposed approach is verified by simulated and real projection fringes as well as the comparison with the widely used and well-known Fourier transform method and wavelet transform method.

  18. DISCOVERING SIGNIFICANT EVOLUTION PATTERNS FROM SATELLITE IMAGE TIME SERIES

    E-print Network

    Paris-Sud XI, Université de

    pixel (the radiometric levels of different wavelengths corresponding to infra-red, red, etc.), which. The next generation of satellites (e.g., V enµs, Sentinel-2) will actually be able to acquire image time

  19. Multiscale recurrent pattern image coding with a flexible partition scheme

    Microsoft Academic Search

    Nelson C. Francisco; Nuno M. M. Rodrigues; Eduardo A. B. Da Silva; Murilo B. De Carvalho; Sérgio M. M. De Faria; Vítor Manuel Mendes Da Silva; Manuel J. C. S. Reis

    2008-01-01

    In this paper we present a new segmentation method for the Multidimensional Multiscale Parser (MMP) algorithm. In previous works we have shown that, for text and com- pound images, MMP has better compression efficiency than state-of-the-art transform-based encoders like JPEG2000 and H.264\\/AVC; however, it is still inferior to them for smooth images. In this paper we improve the performance of

  20. Multi-Scale Fractal Analysis of Image Texture and Pattern

    NASA Technical Reports Server (NTRS)

    Emerson, Charles W.; Quattrochi, Dale A.; Luvall, Jeffrey C.

    1997-01-01

    Fractals embody important ideas of self-similarity, in which the spatial behavior or appearance of a system is largely scale-independent. Self-similarity is a property of curves or surfaces where each part is indistinguishable from the whole. The fractal dimension D of remote sensing data yields quantitative insight on the spatial complexity and information content contained within these data. Analyses of Normalized Difference Vegetation Index (NDVI) images of homogeneous land covers near Huntsville, Alabama revealed that the fractal dimension of an image of an agricultural land cover indicates greater complexity as pixel size increases, a forested land cover gradually grows smoother, and an urban image remains roughly self-similar over the range of pixel sizes analyzed(l0 to 80 meters). The forested scene behaves as one would expect-larger pixel sizes decrease the complexity of the image as individual clumps of trees are averaged into larger blocks. The increased complexity of the agricultural image with increasing pixel size results from the loss of homogeneous groups of pixels in the large fields to mixed pixels composed of varying combinations of NDVI values that correspond to roads and vegetation. The same process occur's in the urban image to some extent, but the lack of large, homogeneous areas in the high resolution NDVI image means the initially high D value is maintained as pixel size increases. The slope of the fractal dimension-resolution relationship provides indications of how image classification or feature identification will be affected by changes in sensor resolution.

  1. Automatic Assessment and Reduction of Noise using Edge Pattern Analysis in Non-Linear Image Enhancement

    NASA Technical Reports Server (NTRS)

    Jobson, Daniel J.; Rahman, Zia-Ur; Woodell, Glenn A.; Hines, Glenn D.

    2004-01-01

    Noise is the primary visibility limit in the process of non-linear image enhancement, and is no longer a statistically stable additive noise in the post-enhancement image. Therefore novel approaches are needed to both assess and reduce spatially variable noise at this stage in overall image processing. Here we will examine the use of edge pattern analysis both for automatic assessment of spatially variable noise and as a foundation for new noise reduction methods.

  2. Comparing irradiance fields derived from Moderate Resolution Imaging Spectroradiometer airborne simulator cirrus cloud retrievals with solar spectral flux radiometer measurements

    Microsoft Academic Search

    K. Sebastian Schmidt; Peter Pilewskie; Steven Platnick; Gala Wind; Ping Yang; Manfred Wendisch

    2007-01-01

    During the Cirrus Regional Study of Tropical Anvils and Cirrus Layers–Florida Area Cirrus Experiment, the Moderate Resolution Imaging Spectroradiometer (MODIS) airborne simulator (MAS) and the solar spectral flux radiometer (SSFR) operated on the same aircraft, the NASA ER-2. While MAS provided two-dimensional horizontal fields of cloud optical thickness and effective ice particle radius, the SSFR measured spectral irradiance in the

  3. Cross-linking patterns and their images in swollen and deformed gels

    E-print Network

    Sergey Panyukov; Yitzhak Rabin

    2015-07-10

    Using the theory of elasticity of polymer gels we show that large-scale cross-link density patterns written into the structure of the network in the melt state, can be revealed upon swelling by monitoring the monomer density patterns. We find that while isotropic deformations in good solvent yield magnified images of the original pattern, anisotropic deformations distort the image (both types of deformation yield affinely stretched images in $\\theta$ solvents). We show that in ordinary solids with spatially inhomogeneous profile of the shear modulus, isotropic stretching leads to distorted density image of this profile under isotropic deformation. Using simple physical arguments we demonstrate that the different response to isotropic stretching stems from fundamental differences between the theory of elasticity of solids and that of gels. Possible tests of our predictions and some potential applications are discussed.

  4. Staining Pattern Classification of Antinuclear Autoantibodies Based on Block Segmentation in Indirect Immunofluorescence Images

    PubMed Central

    Li, Jiaqian; Tseng, Kuo-Kun; Hsieh, Zu Yi; Yang, Ching Wen; Huang, Huang-Nan

    2014-01-01

    Indirect immunofluorescence based on HEp-2 cell substrate is the most commonly used staining method for antinuclear autoantibodies associated with different types of autoimmune pathologies. The aim of this paper is to design an automatic system to identify the staining patterns based on block segmentation compared to the cell segmentation most used in previous research. Various feature descriptors and classifiers are tested and compared in the classification of the staining pattern of blocks and it is found that the technique of the combination of the local binary pattern and the k-nearest neighbor algorithm achieve the best performance. Relying on the results of block pattern classification, experiments on the whole images show that classifier fusion rules are able to identify the staining patterns of the whole well (specimen image) with a total accuracy of about 94.62%. PMID:25474260

  5. CERES CLoud Effects

    NSDL National Science Digital Library

    1997-06-06

    This computer-generated animation depicts the Clouds and the Earth's Radiant Energy System (CERES) instrument in operation. CERES measures the energy at the top of the atmosphere and estimates energy levels in the atmosphere and at the Earth's surface. Using information from very high resolution cloud-imaging instruments on the same spacecraft, CERES also will determine cloud properties, including cloud amount, altitude, thickness, and the size of the cloud particles.

  6. Spatial Uncertainty Modeling of Fuzzy Information in Images for Pattern Classification

    PubMed Central

    Pham, Tuan D.

    2014-01-01

    The modeling of the spatial distribution of image properties is important for many pattern recognition problems in science and engineering. Mathematical methods are needed to quantify the variability of this spatial distribution based on which a decision of classification can be made in an optimal sense. However, image properties are often subject to uncertainty due to both incomplete and imprecise information. This paper presents an integrated approach for estimating the spatial uncertainty of vagueness in images using the theory of geostatistics and the calculus of probability measures of fuzzy events. Such a model for the quantification of spatial uncertainty is utilized as a new image feature extraction method, based on which classifiers can be trained to perform the task of pattern recognition. Applications of the proposed algorithm to the classification of various types of image data suggest the usefulness of the proposed uncertainty modeling technique for texture feature extraction. PMID:25157744

  7. Pattern-based content lossless compression of Chinese document images

    Microsoft Academic Search

    Maggie M. K. Tsui; Alan Wee-Chung Liew; Hong Yan

    2004-01-01

    Compression of scanned text document images is important in modern document management, communications and retrieval systems. However, most existing compression techniques have been studied extensively only for documents in English or similar alphabet-based languages. In this paper, we purpose a content-lossless scheme for compression of Chinese text documents. This method utilizes the radical characteristics, unique to Chinese characters, to minimize

  8. Automated Interpretation of Subcellular Patterns in Fluorescence Microscope Images

    E-print Network

    Gordon, Geoffrey J.

    . Second, it will provide tools for Cytomics projects aimed at characterizing the behaviors of all cell of proteomics projects, have provided rich data sets and enabled biological questions to be addressed the subcellular location of a protein from fluores- cence microscope images (1­7). Location proteomics is im

  9. Optical thickness and effective radius of Arctic boundary-layer clouds retrieved from airborne nadir and imaging spectrometry

    NASA Astrophysics Data System (ADS)

    Bierwirth, E.; Ehrlich, A.; Wendisch, M.; Gayet, J.-F.; Gourbeyre, C.; Dupuy, R.; Herber, A.; Neuber, R.; Lampert, A.

    2013-05-01

    Arctic boundary-layer clouds in the vicinity of Svalbard (78° N, 15° E) were observed with airborne remote sensing and in situ methods. The cloud optical thickness and the droplet effective radius are retrieved from spectral radiance data from the nadir spot (1.5°, 350-2100 nm) and from a nadir-centred image (40°, 400-1000 nm). Two approaches are used for the nadir retrieval, combining the signal from either two or five wavelengths. Two wavelengths are found to be sufficient for an accurate retrieval of the cloud optical thickness, while the retrieval of droplet effective radius is more sensitive to the number of wavelengths. Even with the comparison to in-situ data, it is not possible to definitely answer the question which method is better. This is due to unavoidable time delays between the in-situ measurements and the remote-sensing observations, and to the scarcity of vertical in-situ profiles within the cloud.

  10. Feature correlation for particle image velocimetry: An application of pattern recognition

    SciTech Connect

    Zhang, X.; Cox, C.S. [Univ. of California, San Diego, La Jolla, CA (United States). Scripps Institution of Oceanography

    1995-12-31

    Particle Image Velocimetry (PIV) has been used successfully for measuring instantaneous two dimensional velocity fields. Analyzing PIV images involves matching particle images captured sequentially. A feature-recognition method is proposed here for analyzing PIV images. It first extracts structural features of the particle pattern after their locations have been isolated from images. A preliminary process is to replace the particle images by the Cartesian coordinates of particle centers. In this way the brightness of particle images plays no further part, and the point positions are used to establish structural features: topological relations between each point and its neighbors. The interrogation area is defined by a limited number of neighboring points. The size and shape of each interrogation area varies with the distribution of neighbors. A fit to motion, rotation and distortion among the neighbors is then carried out in the space of topological relations of successive images. In this way changes of structural features define fluid spatial translation, rotation, and deformations within each interrogation region. Measurement of feature space in two successive images demands knowledge of the locations of corresponding points derived from individual particles in the two images. Classification of point correspondences, despite confusingly discordant displacements from one image to the next, can be made by taking advantage of physical limitations on the possible movement of particles between the two images. It is found that feature space search and correlation is a much more efficient procedure than correlation operations in the two dimensional image domain.

  11. Computer-aided diagnosis of splenic enlargement using wave pattern of spleen in abdominal CT images

    NASA Astrophysics Data System (ADS)

    Seong, Won; Cho, June-Sik; Noh, Seung-Moo; Park, Jong Won

    2006-03-01

    It is known that the spleen accompanied by liver cirrhosis is hypertrophied or enlarged. We have examined a wave pattern at the left boundary of spleen on the abdominal CT images having liver cirrhosis, and found that they are different from those on the images having a normal liver. It is noticed that the abdominal CT images of patient with liver cirrhosis shows strong bending in the wave pattern. In the case of normal liver, the images may also have a wave pattern, but its bends are not strong. Therefore, the total waving area of the spleen with liver cirrhosis is found to be greater than that of the spleen with a normal liver. Moreover, we found that the waves of the spleen from the image with liver cirrhosis have the higher degree of circularity compared to the normal liver case. Based on the two observations above, we propose an automatic method to diagnose splenic enlargement by using the wave pattern of the spleen in abdominal CT images. The proposed automatic method improves the diagnostic performance compared with the conventional process based on the size of spleen.

  12. Bayer patterned high dynamic range image reconstruction using adaptive weighting function

    NASA Astrophysics Data System (ADS)

    Kang, Hee; Lee, Suk Ho; Song, Ki Sun; Kang, Moon Gi

    2014-12-01

    It is not easy to acquire a desired high dynamic range (HDR) image directly from a camera due to the limited dynamic range of most image sensors. Therefore, generally, a post-process called HDR image reconstruction is used, which reconstructs an HDR image from a set of differently exposed images to overcome the limited dynamic range. However, conventional HDR image reconstruction methods suffer from noise factors and ghost artifacts. This is due to the fact that the input images taken with a short exposure time contain much noise in the dark regions, which contributes to increased noise in the corresponding dark regions of the reconstructed HDR image. Furthermore, since input images are acquired at different times, the images contain different motion information, which results in ghost artifacts. In this paper, we propose an HDR image reconstruction method which reduces the impact of the noise factors and prevents ghost artifacts. To reduce the influence of the noise factors, the weighting function, which determines the contribution of a certain input image to the reconstructed HDR image, is designed to adapt to the exposure time and local motions. Furthermore, the weighting function is designed to exclude ghosting regions by considering the differences of the luminance and the chrominance values between several input images. Unlike conventional methods, which generally work on a color image processed by the image processing module (IPM), the proposed method works directly on the Bayer raw image. This allows for a linear camera response function and also improves the efficiency in hardware implementation. Experimental results show that the proposed method can reconstruct high-quality Bayer patterned HDR images while being robust against ghost artifacts and noise factors.

  13. A comparison of performance of automatic cloud coverage assessment algorithm for Formosat-2 image using clustering-based and spatial thresholding methods

    NASA Astrophysics Data System (ADS)

    Hsu, Kuo-Hsien

    2012-11-01

    Formosat-2 image is a kind of high-spatial-resolution (2 meters GSD) remote sensing satellite data, which includes one panchromatic band and four multispectral bands (Blue, Green, Red, near-infrared). An essential sector in the daily processing of received Formosat-2 image is to estimate the cloud statistic of image using Automatic Cloud Coverage Assessment (ACCA) algorithm. The information of cloud statistic of image is subsequently recorded as an important metadata for image product catalog. In this paper, we propose an ACCA method with two consecutive stages: preprocessing and post-processing analysis. For pre-processing analysis, the un-supervised K-means classification, Sobel's method, thresholding method, non-cloudy pixels reexamination, and cross-band filter method are implemented in sequence for cloud statistic determination. For post-processing analysis, Box-Counting fractal method is implemented. In other words, the cloud statistic is firstly determined via pre-processing analysis, the correctness of cloud statistic of image of different spectral band is eventually cross-examined qualitatively and quantitatively via post-processing analysis. The selection of an appropriate thresholding method is very critical to the result of ACCA method. Therefore, in this work, We firstly conduct a series of experiments of the clustering-based and spatial thresholding methods that include Otsu's, Local Entropy(LE), Joint Entropy(JE), Global Entropy(GE), and Global Relative Entropy(GRE) method, for performance comparison. The result shows that Otsu's and GE methods both perform better than others for Formosat-2 image. Additionally, our proposed ACCA method by selecting Otsu's method as the threshoding method has successfully extracted the cloudy pixels of Formosat-2 image for accurate cloud statistic estimation.

  14. BIOCAT: a pattern recognition platform for customizable biological image classification and annotation

    PubMed Central

    2013-01-01

    Background Pattern recognition algorithms are useful in bioimage informatics applications such as quantifying cellular and subcellular objects, annotating gene expressions, and classifying phenotypes. To provide effective and efficient image classification and annotation for the ever-increasing microscopic images, it is desirable to have tools that can combine and compare various algorithms, and build customizable solution for different biological problems. However, current tools often offer a limited solution in generating user-friendly and extensible tools for annotating higher dimensional images that correspond to multiple complicated categories. Results We develop the BIOimage Classification and Annotation Tool (BIOCAT). It is able to apply pattern recognition algorithms to two- and three-dimensional biological image sets as well as regions of interest (ROIs) in individual images for automatic classification and annotation. We also propose a 3D anisotropic wavelet feature extractor for extracting textural features from 3D images with xy-z resolution disparity. The extractor is one of the about 20 built-in algorithms of feature extractors, selectors and classifiers in BIOCAT. The algorithms are modularized so that they can be “chained” in a customizable way to form adaptive solution for various problems, and the plugin-based extensibility gives the tool an open architecture to incorporate future algorithms. We have applied BIOCAT to classification and annotation of images and ROIs of different properties with applications in cell biology and neuroscience. Conclusions BIOCAT provides a user-friendly, portable platform for pattern recognition based biological image classification of two- and three- dimensional images and ROIs. We show, via diverse case studies, that different algorithms and their combinations have different suitability for various problems. The customizability of BIOCAT is thus expected to be useful for providing effective and efficient solutions for a variety of biological problems involving image classification and annotation. We also demonstrate the effectiveness of 3D anisotropic wavelet in classifying both 3D image sets and ROIs. PMID:24090164

  15. Method for reducing Newton's rings pattern in the scanned image reproduced with film scanners

    NASA Astrophysics Data System (ADS)

    Lu, Ming-feng; Ni, Guo-qiang; Wang, Tao; Zhang, Feng; Tao, Ran; Yuan, Jun

    2013-12-01

    Newton's rings pattern always blurs the scanned image when scanning a film using a film scanner. Such phenomenon is a kind of equal thickness interference, which is caused by the air layer between the film and the glass of the scanner. A lot of methods were proposed to prevent the interference, such as film holder, anti-Newton's rings glass and emulsion direct imaging technology, etc. Those methods are expensive and lack of flexibility. In this paper, Newton's rings pattern is proved to be a 2-D chirp signal. Then, the fractional Fourier transform, which can be understood as the chirp-based decomposition, is introduced to process Newton's rings pattern. A digital filtering method in the fractional Fourier domain is proposed to reduce the Newton's rings pattern. The effectiveness of the proposed method is verified by simulation. Compared with the traditional optical method, the proposed method is more flexible and low cost.

  16. Model-based classification methods of global patterns in dermoscopic images.

    PubMed

    Sáez, Aurora; Serrano, Carmen; Acha, Begoña

    2014-05-01

    In this paper different model-based methods of classification of global patterns in dermoscopic images are proposed. Global patterns identification is included in the pattern analysis framework, the melanoma diagnosis method most used among dermatologists. The modeling is performed in two senses: first a dermoscopic image is modeled by a finite symmetric conditional Markov model applied to L?a?b? color space and the estimated parameters of this model are treated as features. In turn, the distribution of these features are supposed that follow different models along a lesion: a Gaussian model, a Gaussian mixture model, and a bag-of-features histogram model. For each case, the classification is carried out by an image retrieval approach with different distance metrics. The main objective is to classify a whole pigmented lesion into three possible patterns: globular, homogeneous, and reticular. An extensive evaluation of the performance of each method has been carried out on an image database extracted from a public Atlas of Dermoscopy. The best classification success rate is achieved by the Gaussian mixture model-based method with a 78.44% success rate in average. In a further evaluation the multicomponent pattern is analyzed obtaining a 72.91% success rate. PMID:24770918

  17. Local spatial binary pattern: a new feature descriptor for content-based image retrieval

    NASA Astrophysics Data System (ADS)

    Xia, Yu; Wan, Shouhong; Yue, Lihua

    2014-01-01

    In this paper, we propose a novel image retrieval algorithm using local spatial binary patterns (LSBP) for contentbased image retrieval. The traditional local binary pattern (LBP) encodes the relationship between the referenced pixel and its surrounding neighbors by calculating gray-level difference, but LBP lacks the spatial distribution information of texture direction. The proposed method encodes spatial relationship of the referenced pixel and its neighbors, based on the gray-level variation patterns of the horizontal, vertical and oblique directions. Additionally, variation between center pixel and its surrounding neighbors is calculated to reflect the magnitude information of the whole image. We compare our method with LBP, uniform LBP (ULBP), completed LBP (CLBP), local ternary pattern (LTP) and local tetra patterns (LTrP) based on three benchmark image databases including, Brodatz texture database(DB1), Corel database(DB2), and MIT VisTex database(DB3). Experiment analysis shows that the proposed method improves the retrieval results from 70.49%/41.30% to 73.26%/46.26% in terms of average precision/average recall on database DB2, from 79.02% to 85.92% and 82.14% to 90.88% in terms of average precision on databases DB1 and DB3, respectively, as compared with the traditional LBP.

  18. Using aberration test patterns to optimize the performance of EUV aerial imaging microscopes

    SciTech Connect

    Mochi, Iacopo; Goldberg, Kenneth A.; Miyakawa, Ryan; Naulleau, Patrick; Han, Hak-Seung; Huh, Sungmin

    2009-06-16

    The SEMATECH Berkeley Actinic Inspection Tool (AIT) is a prototype EUV-wavelength zoneplate microscope that provides high quality aerial image measurements of EUV reticles. To simplify and improve the alignment procedure we have created and tested arrays of aberration-sensitive patterns on EUV reticles and we have compared their images collected with the AIT to the expected shapes obtained by simulating the theoretical wavefront of the system. We obtained a consistent measure of coma and astigmatism in the center of the field of view using two different patterns, revealing a misalignment condition in the optics.

  19. Clinician image review patterns in an outpatient setting

    NASA Astrophysics Data System (ADS)

    Erickson, Bradley J.; Ryan, William J.; Gehring, Dale G.; Beebe, Calvin

    1998-07-01

    We have previously described a system for delivering radiology information to the desktop computers used for the electronic medical record (EMR). The system was built with the ability to record physician usage to a database. This usage information was then studied to help understand the value and requirements of an application that could display radiology information on the EMR workstations. This system was used by both primary care physicians and specialists primarily in the out-patient setting. We found that while there was substantial variation in usage both within and between the two physician groups, there was a high degree of support for maintaining image display capabilities on the workstations.

  20. Cloud Computing for radiologists

    PubMed Central

    Kharat, Amit T; Safvi, Amjad; Thind, SS; Singh, Amarjit

    2012-01-01

    Cloud computing is a concept wherein a computer grid is created using the Internet with the sole purpose of utilizing shared resources such as computer software, hardware, on a pay-per-use model. Using Cloud computing, radiology users can efficiently manage multimodality imaging units by using the latest software and hardware without paying huge upfront costs. Cloud computing systems usually work on public, private, hybrid, or community models. Using the various components of a Cloud, such as applications, client, infrastructure, storage, services, and processing power, Cloud computing can help imaging units rapidly scale and descale operations and avoid huge spending on maintenance of costly applications and storage. Cloud computing allows flexibility in imaging. It sets free radiology from the confines of a hospital and creates a virtual mobile office. The downsides to Cloud computing involve security and privacy issues which need to be addressed to ensure the success of Cloud computing in the future. PMID:23599560

  1. An open-source engine for the processing of electron backscatter patterns: EBSD-image.

    PubMed

    Pinard, Philippe T; Lagacé, Marin; Hovington, Pierre; Thibault, Denis; Gauvin, Raynald

    2011-06-01

    An open source software package dedicated to processing stored electron backscatter patterns is presented. The package gives users full control over the type and order of operations that are performed on electron backscatter diffraction (EBSD) patterns as well as the results obtained. The current version of EBSD-Image (www.ebsd-image.org) offers a flexible and structured interface to calculate various quality metrics over large datasets. It includes unique features such as practical file formats for storing diffraction patterns and analysis results, stitching of mappings with automatic reorganization of their diffraction patterns, and routines for processing data on a distributed computer grid. Implementations of the algorithms used in the software are described and benchmarked using simulated diffraction patterns. Using those simulated EBSD patterns, the detection of Kikuchi bands in EBSD-Image was found to be comparable to commercially available EBSD systems. In addition, 24 quality metrics were evaluated based on the ability to assess the level of deformation in two samples (copper and iron) deformed using 220 grit SiC grinding paper. Fourteen metrics were able to properly measure the deformation gradient of the samples. PMID:21554830

  2. Searching for patterns in remote sensing image databases using neural networks

    NASA Technical Reports Server (NTRS)

    Paola, Justin D.; Schowengerdt, Robert A.

    1995-01-01

    We have investigated a method, based on a successful neural network multispectral image classification system, of searching for single patterns in remote sensing databases. While defining the pattern to search for and the feature to be used for that search (spectral, spatial, temporal, etc.) is challenging, a more difficult task is selecting competing patterns to train against the desired pattern. Schemes for competing pattern selection, including random selection and human interpreted selection, are discussed in the context of an example detection of dense urban areas in Landsat Thematic Mapper imagery. When applying the search to multiple images, a simple normalization method can alleviate the problem of inconsistent image calibration. Another potential problem, that of highly compressed data, was found to have a minimal effect on the ability to detect the desired pattern. The neural network algorithm has been implemented using the PVM (Parallel Virtual Machine) library and nearly-optimal speedups have been obtained that help alleviate the long process of searching through imagery.

  3. Spatio-temporal patterns of neuronal activity: analysis of optical imaging data using geometric shape matching.

    PubMed

    Köhling, R; Reinel, J; Vahrenhold, J; Hinrichs, K; Speckmann, E-J

    2002-02-15

    Optical imaging of neuronal network activity yields information of spatial dynamics which generally is analyzed visually. The transient appearance of spatial activity patterns is difficult to gauge in a quantifiable manner, or may even altogether escape detection. Here, we employ geometric shape matching using Fréchet distances or straight skeletons to search for pre-selected patterns in optical imaging data with adjustable degrees of tolerance. Data were sampled from fluorescence changes of a voltage-sensitive dye recorded with a 464-photodiode array. Fluorescence was monitored in a neuronal network in vitro. Neuronal activity prompting fluorescence fluctuations consisted of spontaneous epileptiform discharges in neocortical slices from patients undergoing epilepsy surgery. The experiments show that: (a) spatial activity patterns can be detected in optical imaging data; (b) shapes such as "mini-foci" appear in close correlation to bioelectric discharges monitored with field potential electrodes in a reproducible manner; (c) Fréchet distances yield more conservative matches regarding rectangular, and less conservative hits with respect to radially symmetric shapes than the straight skeleton approach; and (d) tolerances of 0.03-0.1 are suited to detect faithful images of pre-selected shapes, whereas values >0.8 will report matches with any polygonal pattern. In conclusion, the methods reported here are suited to detect and analyze spatial, geometric dynamics in optical imaging data. PMID:11850035

  4. Speckle pattern of the images of objects exposed to monochromatic coherent terahertz radiation

    SciTech Connect

    Vinokurov, Nikolai A; Knyazev, Boris A; Kulipanov, Gennadii N [G.I. Budker Institute of Nuclear Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Dem'yanenko, M A; Esaev, D G [A.V.Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation); Chashchina, O I; Cherkasskii, Valerii S [Novosibirsk State University, Novosibirsk (Russian Federation)

    2009-05-31

    By using a free electron laser and a microbolometer array, real-time images are recorded for the first time in the terahertz range at the rate of up to 90 frames per second. In the case of diffusive illumination of objects by coherent monochromatic radiation, the images consist of speckles. The study of the statistical properties of speckle patterns shows that they are quite accurately described by the theory developed for speckles in the visible range. By averaging a set of images with the help of a rotating scatterer during the exposure time of a frame (20 ms) and by summing statistically independent speckle patterns of many frames, images of the acceptable quality are obtained. The possibilities of terahertz speckle photography and speckle interferometry are discussed. (terahertz radiation)

  5. Preliminary validation of a new variable pattern for daily quality assurance of medical image display devices

    SciTech Connect

    Jacobs, Jurgen; Rogge, Frank; Kotre, John; Marchal, Guy; Bosmans, Hilde [University Hospitals of Leuven, Herestraat 49, Leuven, Brabant 3000 (Belgium); Regional Medical Physics Department, Newcastle General Hospital Newcastle-upon-Tyne, NE4 6BE (United Kingdom); University Hospitals of Leuven, Herestraat 49, Leuven, Brabant 3000 (Belgium)

    2007-07-15

    This paper reports on a comparative study between the well-established test patterns for daily quality assurance (QA) of monitors of the American Association of Medical Physicists, Task Group 18 (AAPMtg18) and the Deutsches Institut fuer Normung e.V (DIN), and a newly proposed variable test pattern. A characteristic of the test patterns currently used for the QA of monitors is their static nature: The same test pattern is always used. This enables a learning effect that may bias the results over time. To address this problem we have developed a variable pattern for the quality assurance of monitors (MoniQA) that allows an evaluation of contrast visibility, geometric distortion, resolution, global image quality including uniformity, and artifacts. The test pattern includes randomly generated elements intended to prevent the observer from learning the test. Examples are random characters that have to be discriminated from the background to evaluate the threshold luminance difference and variable positions of different features in the test pattern. The newly proposed test patterns were generated and visualized on different viewing stations with a software tool developed in JAVA. In this study, we validated these patterns against the well-known AAPMtg18 and DIN test patterns on 22 monitors. The results showed that the MoniQA test can indicate the same monitor problems as the other well-known patterns and is significantly quicker to evaluate than the AAPMtg18 test patterns. The MoniQA pattern is a promising alternative for daily quality control of medical viewing stations.

  6. Investigation of mesoscale cloud features viewed by LANDSAT

    NASA Technical Reports Server (NTRS)

    Sherr, P. E. (principal investigator); Feteris, P. J.; Lisa, A. S.; Bowley, C. J.; Fowler, M. G.; Barnes, J. C.

    1976-01-01

    The author has identified the following significant results. Some 50 LANDSAT images displaying mesoscale cloud features were analyzed. This analysis was based on the Rayleigh-Kuettner model describing the formation of that type of mesoscale cloud feature. This model lends itself to computation of the average wind speed in northerly flow from the dimensions of the cloud band configurations measured from a LANDSAT image. In nearly every case, necessary conditions of a curved wind profile and orientation of the cloud streets within 20 degrees of the direction of the mean wind in the convective layer were met. Verification of the results by direct observation was hampered, however, by the incompatibility of the resolution of conventional rawinsonde observations with the scale of the banded cloud patterns measured from LANDSAT data. Comparison seems to be somewhat better in northerly flows than in southerly flows, with the largest discrepancies in wind speed being within 8m/sec, or a factor of two.

  7. Using Time-Series Satellite Imaging Radar Data to Monitor Inundation Patterns and Hydroperiod in Herbaceous Wetlands of Southern Florida

    NASA Astrophysics Data System (ADS)

    Bourgeau-Chavez, L. L.; Kasischke, E.

    2002-05-01

    Knowledge of the components of the hydrologic cycle, including spatial and temporal distribution of water, is critical for regional hydrologic applications. However, at a regional scale, the variations of hydrologic condition are often too great to be easily quantified with ground-based observations alone. We developed methods to use satellite imaging radar data to monitor changes in hydrologic condition of regional scale wetland ecosystems in south Florida. Satellite imaging radar data have been shown to be sensitive to soil moisture variations and to flood conditions in a variety of wetland ecosystems. Initial observations of south Florida imagery from the European Space Agency's C-band microwave sensor onboard the European Remote Sensing Satellite (ERS) showed dynamic variations in backscatter between wet and dry seasons. Further studies revealed how fluctuations in water level influenced ERS radar backscatter for several different herbaceous vegetation cover types. Unfortunately, the C-band wavelength is incapable of penetrating dense forested canopies, thus, our research was focused on the vast herbaceous wetland ecosystems of southern Florida. The ERS synthetic aperture radar (SAR) sensor is a C-band, 5.7 cm wavelength imaging radar with vertical transmit and receive polarization (C-VV). The ERS sensor has a resolution of 30 m and a footprint of 100 by 100 km. SARs have the unique capability to collect data independent of cloud cover and solar illumination. This provides an advantage in areas typically covered by clouds such as tropical and sub-tropical regions like south Florida. In this study, several techniques were developed to utilize SAR data to detect, monitor, and map spatial and temporal changes in wetland hydrology. This study shows that radar imagery can be used to create innundation maps of relative soil moisture and flooding in herbaceous wetlands. Using C-band SAR imagery collected between 1997 and 1999, hydropattern maps were created at approximately bi-monthly periods for the south Florida region. In addition, a methodology for creating hydroperiod (the time period of flooding) maps was developed and examples from wet and dry years are presented. Principal component Analysis (PCA) was the basis of our hydroperiod maps and was linked to rainfall patterns of the south Florida region. Validation of the maps was conducted with in situ data and review by experts in the region.

  8. Sensitivity of Satellite-Retrieved Cloud Properties to the Effective Variance of Cloud Droplet Size Distribution

    SciTech Connect

    Arduini, R.F.; Minnis, P.; Smith, W.L.Jr.; Ayers, J.K.; Khaiyer, M.M.; Heck, P.

    2005-03-18

    Cloud reflectance models currently used in cloud property retrievals from satellites have been developed using size distributions defined by a set of fixed effective radii with a fixed effective variance. The satellite retrievals used for the Atmospheric Radiation Measurement (ARM) program assume droplet size distributions with an effective variance value of 0.10 (Minnis et al. 1998); the International Satellite Cloud Climatology Project uses 0.15 (Rossow and Schiffer 1999); and the Moderate Resolution Imaging Spectroradiometer (MODIS) team uses 0.13 (Nakajima and King 1990). These distributions are not necessarily representative of the actual sizes present in the clouds being observed. Because the assumed distributions can affect the reflectance patterns and near-infrared absorption, even for the same droplet effective radius reff, it is desirable to use the optimal size distributions in satellite retrievals of cloud properties. Collocated observations of the same clouds from different geostationary satellites, at different viewing angles, indicate that the current models may not be optimal (Ayers et al. 2005). Similarly, hour-to-hour variations in effective radius and optical depth reveal an unexplained dependence on scattering angle. To explore this issue, this paper examines the sensitivity of the cloud reflectance at 0.65 and 3.90-{micro}m to changes in the effective variance, or the spectral dispersion, of the modeled size distributions. The effects on the scattering phase functions and on the cloud reflectances are presented, as well as some resultant effects on the retrieved cloud properties.

  9. Focussing on the future: survey results on the image capture of patterned cutaneous injuries.

    PubMed

    Evans, Sam; Baylis, Sonya; Carabott, Romina; Jones, Michael; Lawson, Zoe; Marsh, Nick; Payne-James, Jason; Ramadani, Jona; Vanezis, Peter; Kemp, Alison

    2014-05-01

    An investigator who is involved in assessing the likelihood of physical abuse must make a decision as to whether the injury seen matches the explanation given. In some instances the pattern of these injuries can give the investigator a possible link to the cause of the injury. Photographic imaging is used to record the patterned cutaneous injuries (PCI) and to facilitate forensic interpretation. The current method of capturing PCI often results in some form of distortion that causes a change to the shape of the patterned injury. The Dermatological Patterned Injury Capture and Analysis (DePICA) research group was formed to assess current image capture methods and practices. An online survey was set up to assess the value of localised imaging protocols and training specific to imaging PCI and was made available to law enforcement professionals, forensic investigators and hospital staff. 80 participants responded to the survey. The majority of the survey participants have had training in medical or forensic photography, however 66 (83%) have not had specific training in how to photograph PCI. 41 (51%) of the participants responded that they always use a rigid scale and 34 (43%) position the camera so that it is perpendicular to the scale and injury. Comments made about the quality of images obtained and produced raises concerns about how much knowledge those initiating such images have about image relevance in criminal cases. It is evident that a clear and comprehensive guide to photographing PCIs is required to improve the quality of the photographic evidence that is collected. PMID:24794842

  10. Capsule and mosaic pattern of hepatocellular carcinoma: Correlation between CT and MR imaging

    Microsoft Academic Search

    Lucie Lalonde; Bernard Van Beers; Jacques Jamart; Jacques Pringot

    1992-01-01

    Computed tomography (CT) was compared with magnetic resonance (MR) imaging in depicting the capsule and the mosaic pattern of hepatocellular carcinoma in 34 patients. The kappa statistic was used to compare results from both modalities. For the detection of the capsule, there was a substantial agreement beyond chance between late enhanced CT (more than 5 min after dynamic CT) and

  11. Improving multiscale recurrent pattern image coding with enhanced dictionary updating strategies

    Microsoft Academic Search

    Nuno M. M. Rodrigues; E. A. B. da Silva; M. B. de Carvalho; S. M. M. de Faria; V. M. M. da Silva

    2006-01-01

    The multidimensional multiscale parser (MMP) is a lossy multidimensional signal encoder, that uses an adaptive dictionary for approximating the original signal using multiscale recurrent pattern matching. In previous work we have shown the efficiency of MMP for image coding and we have also described new techniques to improve its performance, using predictive coding (MMP-Intra) and innovative strategies for reducing the

  12. Patterned interrogation scheme for compressed sensing photoacoustic imaging using a Fabry Perot planar sensor

    NASA Astrophysics Data System (ADS)

    Huynh, Nam; Zhang, Edward; Betcke, Marta; Arridge, Simon; Beard, Paul; Cox, Ben

    2014-03-01

    Photoacoustic tomography (PAT) has become a powerful tool for biomedical imaging, particularly pre-clinical small animal imaging. Several different measurement systems have been demonstrated, in particular, optically addressed Fabry-Perot interferometer (FPI) sensors have been shown to provide exquisite images when a planar geometry is suitable. However, in its current incarnation the measurements must be made at each point sequentially, so these devices therefore suffer from slow data acquisition time. An alternative to this point-by-point interrogation scheme, is to interrogate the whole sensor with a series of independent patterns, so each measurement is the spatial integral of the product of the pattern and the acoustic field (as in the single-pixel Rice camera). Such an interrogation scheme allows compressed sensing to be used. This enables the number of measurements to be reduced significantly, leading to much faster data acquisition. An experimental implementation will be described, which employs a wide NIR tunable laser beam to interrogate the FPI sensor. The reflected beam is patterned by a digital micro-mirror device, and then focused to a single photodiode. To demonstrate the idea of patterned and compressed sensing for ultrasound detection, a scrambled Hadamard operator is used in the experiments. Photoacoustic imaging experiments of phantoms shows good reconstructed results with 20% compression.

  13. Some Extensions of the K-Means Algorithm for Image Segmentation and Pattern Classification

    Microsoft Academic Search

    Federico Girosi; Jose L. Marroquin

    1993-01-01

    In this paper we present some extensions to the k-means algorithm for vector quantizationthat permit its efficient use in image segmentation and pattern classification tasks. Itis shown that by introducing state variables that correspond to certain statistics of thedynamic behavior of the algorithm, it is possible to find the representative centers ofthe lower dimensional manifolds that define the boundaries between

  14. Learning local binary patterns for gender classification on real-world face images Caifeng Shan

    E-print Network

    Kim, Tae-Kyun

    built database, the Labeled Faces in the Wild (LFW). Local Binary Patterns (LBP) is employed to describe.81% by applying Support Vector Machine (SVM) with the boosted LBP features. The public database used in this study network, SEX- NET, which achieves the recognition accuracy of 91.9% on 90 face images. Recent years have

  15. Full-field measurements of heterogeneous deformation patterns on polymeric foams using digital image correlation

    Microsoft Academic Search

    Yu Wang; Alberto M Cuitiño

    2002-01-01

    The ability of a digital image correlation technique to capture the heterogeneous deformation fields appearing during compression of ultra-light open-cell foams is presented in this article. Quantitative characterization of these fields is of importance to understand the mechanical properties of the collapse process and the energy dissipation patterns in this type of materials. The present algorithm is formulated in the

  16. Pattern-based compression of text images Andrei Broder Michael Mitzenmacher*

    E-print Network

    Mitzenmacher, Michael

    be modified to yield a lossless scheme that improves compression at the expense of primarily compression timePattern-based compression of text images Andrei Broder Michael Mitzenmacher* Digital Syst. Res approach will be applica- ble in other domains as well. 1 Introduction We consider a compression scheme

  17. Image and Pattern Analysis of 1650 B.C. Wall Paintings and Reconstruction

    Microsoft Academic Search

    Constantin Papaodysseus; Mihalis Exarhos; Mihalis Panagopoulos; Panayiotis Rousopoulos; Constantin Triantafillou; Thanasis Panagopoulos

    2008-01-01

    In this paper, a color image segmentation method and a pattern analysis are presented, in connection with the extraordinary 1650 B.C. wall paintings found in the Greek island of Thera. These wall paintings are usually reconstructed from thousands of fragments widely scattered in the excavated site. The fragments' depiction manifests inhomogeneous color decay, cracks, added extraneous material, etc. The proposed

  18. Feature mining and pattern classification for steganalysis of LSB matching steganography in grayscale images

    Microsoft Academic Search

    Qingzhong Liu; Andrew H. Sung; Zhongxue Chen; Jianyun Xu

    2008-01-01

    In this paper, we present a scheme based on feature mining and pattern classification to detect LSB matching steganography in grayscale images, which is a very challenging problem in steganalysis. Five types of features are proposed. In comparison with other well-known feature sets, the set of proposed features performs the best. We compare different learning classifiers and deal with the

  19. VITILIGO & NLRP1 Presented by Sarah Hamilton http://www.avrf.org/images/vitiligo-patterns.gif

    E-print Network

    Skop, Ahna

    VITILIGO & NLRP1 Presented by Sarah Hamilton http://www.avrf.org/images/vitiligo-patterns.gif #12;Vitiligo Facts Autoimmune disease ­ loss of melanocytes Affects 2-4 million Americans; 65 million diseases http://www.bio.davidson.edu/Courses/Immunology/Students/Spring2003/Leese/Vitiligo.jpg #12;Vitiligo

  20. Vascular pattern classification of colorectal lesions with narrow band imaging magnifying endoscopy.

    PubMed

    Wada, Yoshiki; Kudo, Shin-ei; Misawa, Masashi; Ikehara, Nobunao; Hamatani, Shigeharu

    2011-05-01

    Magnifying narrow band imaging (NBI) has enabled to observe the vascular pattern of colorectal lesions. Their broad findings have been divided into six groups according to endoscopical vascular features: normal, faint, network, dense, irregular and sparse. Most hyperplastic polyps show a faint pattern. The vascular patterns of adenomas are mainly network or dense ones. The predominant vascular patterns of cancer were irregular and sparse. Indeed, irregular pattern has found to be characteristic for protruded or flat-elevated cancer, whereas sparse pattern unique for depressed cancer. Through NBI, neoplastic lesions could be differentiated from those non-neoplastic with sensitivity of 83.5%, specificity of 98.7% and accuracy of 98.2%. It was able to distinguish between massively submucosal invasive cancers and slightly submucosal invasive cancers by using the vascular pattern with 91.0% sensitivity and 79.4% specificity. The overall accuracy was 88.3%. NBI system has showed to be a valuable technique for distinguishing neoplastic from non-neoplastic lesions, as well as massively from slightly submucosal invasive cancer. Therefore, vascular pattern analysis might be a promising tool for determining treatment selection, whether endoscopical or surgically. PMID:21535214

  1. Synthesis Imaging of Dense Molecular Gas in the N113 HII Region of the Large Magellanic Cloud

    E-print Network

    Tony Wong; John B. Whiteoak; Juergen Ott; Yi-nan Chin; Maria R. Cunningham; )

    2006-04-08

    We present aperture synthesis imaging of dense molecular gas in the Large Magellanic Cloud, taken with the prototype millimeter receivers of the Australia Telescope Compact Array (ATCA). Our observations of the N113 HII region reveal a condensation with a size of ~6" (1.5 pc) FWHM, detected strongly in the 1-0 lines of HCO+, HCN and HNC, and weakly in C_2H. Comparison of the ATCA observations with single-dish maps from the Mopra Telescope and sensitive spectra from the Swedish-ESO Submillimetre Telescope indicates that the condensation is a massive clump of ~10^4 solar masses within a larger ~10^5 solar mass molecular cloud. The clump is centered adjacent to a compact, obscured HII region which is part of a linear structure of radio continuum sources extending across the molecular cloud. We suggest that the clump represents a possible site for triggered star formation. Examining the integrated line intensities as a function of interferometer baseline length, we find evidence for decreasing HCO+/HCN and HCN/HNC ratios on longer baselines. These trends are consistent with a significant component of the HCO+ emission arising in an extended clump envelope and a lower HCN/HNC abundance ratio in dense cores.

  2. Hotspot detection using image pattern recognition based on higher-order local auto-correlation

    NASA Astrophysics Data System (ADS)

    Maeda, Shimon; Matsunawa, Tetsuaki; Ogawa, Ryuji; Ichikawa, Hirotaka; Takahata, Kazuhiro; Miyairi, Masahiro; Kotani, Toshiya; Nojima, Shigeki; Tanaka, Satoshi; Nakagawa, Kei; Saito, Tamaki; Mimotogi, Shoji; Inoue, Soichi; Nosato, Hirokazu; Sakanashi, Hidenori; Kobayashi, Takumi; Murakawa, Masahiro; Higuchi, Tetsuya; Takahashi, Eiichi; Otsu, Nobuyuki

    2011-04-01

    Below 40nm design node, systematic variation due to lithography must be taken into consideration during the early stage of design. So far, litho-aware design using lithography simulation models has been widely applied to assure that designs are printed on silicon without any error. However, the lithography simulation approach is very time consuming, and under time-to-market pressure, repetitive redesign by this approach may result in the missing of the market window. This paper proposes a fast hotspot detection support method by flexible and intelligent vision system image pattern recognition based on Higher-Order Local Autocorrelation. Our method learns the geometrical properties of the given design data without any defects as normal patterns, and automatically detects the design patterns with hotspots from the test data as abnormal patterns. The Higher-Order Local Autocorrelation method can extract features from the graphic image of design pattern, and computational cost of the extraction is constant regardless of the number of design pattern polygons. This approach can reduce turnaround time (TAT) dramatically only on 1CPU, compared with the conventional simulation-based approach, and by distributed processing, this has proven to deliver linear scalability with each additional CPU.

  3. Teaching image processing and pattern recognition with the Intel OpenCV library

    NASA Astrophysics Data System (ADS)

    Koz?owski, Adam; Królak, Aleksandra

    2009-06-01

    In this paper we present an approach to teaching image processing and pattern recognition with the use of the OpenCV library. Image processing, pattern recognition and computer vision are important branches of science and apply to tasks ranging from critical, involving medical diagnostics, to everyday tasks including art and entertainment purposes. It is therefore crucial to provide students of image processing and pattern recognition with the most up-to-date solutions available. In the Institute of Electronics at the Technical University of Lodz we facilitate the teaching process in this subject with the OpenCV library, which is an open-source set of classes, functions and procedures that can be used in programming efficient and innovative algorithms for various purposes. The topics of student projects completed with the help of the OpenCV library range from automatic correction of image quality parameters or creation of panoramic images from video to pedestrian tracking in surveillance camera video sequences or head-movement-based mouse cursor control for the motorically impaired.

  4. Measurement of velocity and velocity derivatives based on pattern tracking in 3D LIF images

    NASA Astrophysics Data System (ADS)

    Deusch, S.; Merava, H.; Dracos, T.; Rys, P.

    Pattern tracking in consecutive 3D LIF images based on least squares matching (LSM) of grey levels has been developed recently for velocity and velocity gradient measurements. The shortcomings of this method are clearly shown. The present article presents an improvement on this method by introducing a local multi-patch (LMP) technique through the LSM approach. The method is validated using the flow field of a turbulent channel flow obtained by direct numerical simulation (DNS) and a synthetic image with grey-level patterns. The results show that LMP matching allows the determination of the velocity and the velocity gradient fields with high accuracy including the second derivatives. Measurements of a round non-buoyant jet are presented which demonstrate the good performance of the method when applied under laboratory conditions. This method can also be applied on two-dimensional images provided that the flow is strictly two-dimensional.

  5. Abnormal Image Detection in Endoscopy Videos Using a Filter Bank and Local Binary Patterns.

    PubMed

    Nawarathna, Ruwan; Oh, JungHwan; Muthukudage, Jayantha; Tavanapong, Wallapak; Wong, Johnny; de Groen, Piet C; Tang, Shou Jiang

    2014-11-20

    Finding mucosal abnormalities (e.g., erythema, blood, ulcer, erosion, and polyp) is one of the most essential tasks during endoscopy video review. Since these abnormalities typically appear in a small number of frames (around 5% of the total frame number), automated detection of frames with an abnormality can save physician's time significantly. In this paper, we propose a new multi-texture analysis method that effectively discerns images showing mucosal abnormalities from the ones without any abnormality since most abnormalities in endoscopy images have textures that are clearly distinguishable from normal textures using an advanced image texture analysis method. The method uses a "texton histogram" of an image block as features. The histogram captures the distribution of different "textons" representing various textures in an endoscopy image. The textons are representative response vectors of an application of a combination of Leung and Malik (LM) filter bank (i.e., a set of image filters) and a set of Local Binary Patterns on the image. Our experimental results indicate that the proposed method achieves 92% recall and 91.8% specificity on wireless capsule endoscopy (WCE) images and 91% recall and 90.8% specificity on colonoscopy images. PMID:25132723

  6. Noise-Produced Patterns in Images Constructed from Magnetic Flux Leakage Data

    E-print Network

    Pimenova, Anastasiya V; Levesley, Jeremy; Elkington, Peter; Bacciarelli, Mark

    2015-01-01

    Magnetic flux leakage measurements help identify the position, size and shape of corrosion-related defects in steel casings used to protect boreholes drilled into oil and gas reservoirs. Images constructed from magnetic flux leakage data contain patterns related to noise inherent in the method. We investigate the patterns and their scaling properties for the case of delta-correlated input noise, and consider the implications for the method's ability to resolve defects. The analytical evaluation of the noise-produced patterns is made possible by model reduction facilitated by large-scale approximation. With appropriate modification, the approach can be employed to analyze noise-produced patterns in other situations where the data of interest are not measured directly, but are related to the measured data by a complex linear transform involving integrations with respect to spatial coordinates.

  7. HOLOGondel: A novel in-situ cloud measurement platform on a cable car with a digital holographic imager

    NASA Astrophysics Data System (ADS)

    Beck, Alexander; Henneberger, Jan; Kanji, Zamin; Lohmann, Ulrike

    2015-04-01

    Cloud particle properties observed in-situ are commonly conducted from airborne or ground-based measurements. When compared to airborne measurements, the advantages of ground-based measurements are a higher spatial resolution and much less costly to perform. However, ground-based observations allow only single-point measurements within a cloud. To overcome this disadvantage, a novel measurement platform with a digital holographic imager has been developed to allow in-situ cloud observations on the roof of a cable car cabin. With a traveling velocity of a cable car of a few m/s, such a measurement platform yields a spatial resolution comparable to those of ground-based measurements. In addition, it is possible to obtain vertical profiles of the microphysical properties within the cloud, because of the vertical distance covered by the cable car of approximately 800m. The major technical challenges for such a measurement platform are the lack of an external power supply and the additional weight constrain on a cable car cabin. To allow continuous operation for eight hours with a battery and to stay within the weight limit of 25kg at the same time, a compact design with carefully chosen material and components with a low power consumption was necessary. The new measurement platform HOLOGondel is equipped with a HOLographic Imager for Microscopic Objects (HOLIMO 3G). Digital in-line holography offers the advantages of measuring simultaneously an ensemble of cloud particles within a well-defined detection volume over a large range of particle size. The image captured, a hologram, yields information about the three-dimensional position, size and a shadow-graph of each particle within the detection volume. The HOLIMO 3G instrument is equipped with a 30MP camera and a 1.8 times magnifying, both-sided telecentric lens system. At a frame rate of six pictures per second a sample volume rate of about 100 cm3s-1 at a maximum resolution of 7 µm is achieved. This configuration allows to measure the vertical profiles of the number concentration and size distribution of liquid cloud droplets and ice crystals, the spatial scale of mixing between these two and the partitioning with respect to particle size. In addition, auxiliary measurements of the temperature, relative humidity and GPS position of the captured images are conducted. A first field campaign will be performed at the Eggishorn in the Bernese Alps from January until March 2015. With its short distance from the research station Jungfraujoch (JFJ) there is a chance to measure the same air masses twice (concurrent measurement with the HOLIMO 3M instrument at JFJ). The comparison of these measurements will contribute to a better understanding of the spatial and temporal evolution of orographic MPCs.

  8. Lacunarity analysis of spatial pattern in CT images of vertebral trabecular bone for assessing osteoporosis.

    PubMed

    Dougherty, Geoffrey; Henebry, Geoffrey M

    2002-03-01

    The structural integrity of vertebral trabecular bone is determined by the continuity of its trabecular network and the size of the holes comprising its marrow space, both of which determine the apparent size of the marrow spaces in a transaxial CT image. A model-independent assessment of the trabeculation pattern was determined from the lacunarity of thresholded CT images. Using test images of lumbar vertebrae from human cadavers, acquired at different slice thicknesses, we determined that both median thresholding and local adaptive thresholding (using a 7 x 7 window) successfully segmented the grey-scale images. Lacunarity analysis indicated a multifractal nature to the images, and a range of marrow space sizes with significant structure around 14-18 mm(2). Preliminary studies of in vivo images from a clinical CT scanner indicate that lacunarity analysis can follow the pattern of bone loss in osteoporosis by monitoring the homogeneity of the marrow spaces, which is related to the connectivity of the trabecular bone network and the marrow space sizes. Although the patient sample was small, derived parameters such as the maximum deviation of the lacunarity from a neutral (fractal) model, and the maximum derivative of this deviation, seem to be sufficiently sensitive to distinguish a range of bone conditions. Our results suggest that these parameters, used with bone mineral density values, may have diagnostic value in characterizing osteoporosis and predicting fracture risk. PMID:11886832

  9. Stochastic simulation of patterns using ISOMAP for dimensionality reduction of training images

    NASA Astrophysics Data System (ADS)

    Zhang, Ting; Du, Yi; Huang, Tao; Yang, Jiaqing; Li, Xue

    2015-06-01

    Most data in the real world are normally nonlinear or difficult to determine whether they are linear or not beforehand. Some linear dimensionality reduction algorithms, e.g., principal component analysis (PCA) and multi-dimensional scaling (MDS) are only suitable for linear dimensionality reduction of spatial data. The patterns extracted from training images (TIs) used in MPS simulation mostly are probably nonlinear, so for some MPS simulation methods based on dimensionality reduction, e.g., FILTERSIM using some filters created via the idea of PCA and DisPAT using MDS as a tool of dimensionality reduction, those linear methods for dimensionality reduction are not appropriate when realizing the dimensionality reduction of nonlinear data of patterns. Therefore, isometric mapping (ISOMAP) working as a nonlinear dimensionality reduction method used in manifold learning is introduced to map those patterns, regardless of being linear or nonlinear, into low-dimensional space. However, because the original ISOMAP has some disadvantages in computing speed and accuracy, landmark points of patterns are selected to improve the speed and neighborhoods of patterns are set to guarantee the quality of dimensionality reduction. Next, the sequential simulation similar to FILTERSIM is performed after low-dimensional data of patterns are classified by a density-based clustering algorithm. The comparisons with FILTERSIM and DisPAT show the improvement of pattern reproductivity and computing speed of our method for both continuous and categorical variables.

  10. Local tetra patterns: a new feature descriptor for content-based image retrieval.

    PubMed

    Murala, Subrahmanyam; Maheshwari, R P; Balasubramanian, R

    2012-05-01

    In this paper, we propose a novel image indexing and retrieval algorithm using local tetra patterns (LTrPs) for content-based image retrieval (CBIR). The standard local binary pattern (LBP) and local ternary pattern (LTP) encode the relationship between the referenced pixel and its surrounding neighbors by computing gray-level difference. The proposed method encodes the relationship between the referenced pixel and its neighbors, based on the directions that are calculated using the first-order derivatives in vertical and horizontal directions. In addition, we propose a generic strategy to compute nth-order LTrP using (n - 1)th-order horizontal and vertical derivatives for efficient CBIR and analyze the effectiveness of our proposed algorithm by combining it with the Gabor transform. The performance of the proposed method is compared with the LBP, the local derivative patterns, and the LTP based on the results obtained using benchmark image databases viz., Corel 1000 database (DB1), Brodatz texture database (DB2), and MIT VisTex database (DB3). Performance analysis shows that the proposed method improves the retrieval result from 70.34%/44.9% to 75.9%/48.7% in terms of average precision/average recall on database DB1, and from 79.97% to 85.30% and 82.23% to 90.02% in terms of average retrieval rate on databases DB2 and DB3, respectively, as compared with the standard LBP. PMID:22514130

  11. Infrared and Optical Imagings of the Comet 2P/Encke Dust Cloud in the 2003 Return

    NASA Astrophysics Data System (ADS)

    Sarugaku, Yuki; Ishiguro, Masateru; Ueno, Munetaka; Usui, Fumihiko; Reach, William T.

    2015-05-01

    We report contemporaneous imaging observations of the short-period comet 2P/Encke in infrared and optical wavelengths during the 2003 return. Both images show the same unique morphology consisting of a spiky dust cloud near the nucleus and a dust trail extending along the orbit. We conducted a dynamical simulation of dust particles to characterize the morphology and found that dust particles were ejected intensively for a short duration (?10 days) a few days after perihelion passage. The maximum particle size is at least on the order of 1 cm in radius following a differential power-law size distribution with an index of ?3.2 to ?3.6. The total mass ejected in the 2003 return is at least 1.5 × 109–1.2 × 1010 kg, which corresponds to 0.003%–0.03% of the nucleus mass. We derived the albedo of the dust cloud as 0.01–0.04 at a solar phase angle of 26.°2, which is consistent with or possibly greater than that of the nucleus. We suppose that impulsive activity such as an outburst is a key to understanding the peculiar appearance of 2P/Encke.

  12. Photoacoustic image patterns of breast carcinoma and comparisons with Magnetic Resonance Imaging and vascular stained histopathology

    PubMed Central

    Heijblom, M.; Piras, D.; Brinkhuis, M.; van Hespen, J. C. G.; van den Engh, F. M.; van der Schaaf, M.; Klaase, J. M.; van Leeuwen, T. G.; Steenbergen, W.; Manohar, S.

    2015-01-01

    Photoacoustic (optoacoustic) imaging can visualize vasculature deep in tissue using the high contrast of hemoglobin to light, with the high-resolution possible with ultrasound detection. Since angiogenesis, one of the hallmarks of cancer, leads to increased vascularity, photoacoustics holds promise in imaging breast cancer as shown in proof-of-principle studies. Here for the first time, we investigate if there are specific photoacoustic appearances of breast malignancies which can be related to the tumor vascularity, using an upgraded research imaging system, the Twente Photoacoustic Mammoscope. In addition to comparisons with x-ray and ultrasound images, in subsets of cases the photoacoustic images were compared with MR images, and with vascular staining in histopathology. We were able to identify lesions in suspect breasts at the expected locations in 28 of 29 cases. We discovered generally three types of photoacoustic appearances reminiscent of contrast enhancement types reported in MR imaging of breast malignancies, and first insights were gained into the relationship with tumor vascularity. PMID:26159440

  13. Photoacoustic image patterns of breast carcinoma and comparisons with Magnetic Resonance Imaging and vascular stained histopathology.

    PubMed

    Heijblom, M; Piras, D; Brinkhuis, M; van Hespen, J C G; van den Engh, F M; van der Schaaf, M; Klaase, J M; van Leeuwen, T G; Steenbergen, W; Manohar, S

    2015-01-01

    Photoacoustic (optoacoustic) imaging can visualize vasculature deep in tissue using the high contrast of hemoglobin to light, with the high-resolution possible with ultrasound detection. Since angiogenesis, one of the hallmarks of cancer, leads to increased vascularity, photoacoustics holds promise in imaging breast cancer as shown in proof-of-principle studies. Here for the first time, we investigate if there are specific photoacoustic appearances of breast malignancies which can be related to the tumor vascularity, using an upgraded research imaging system, the Twente Photoacoustic Mammoscope. In addition to comparisons with x-ray and ultrasound images, in subsets of cases the photoacoustic images were compared with MR images, and with vascular staining in histopathology. We were able to identify lesions in suspect breasts at the expected locations in 28 of 29 cases. We discovered generally three types of photoacoustic appearances reminiscent of contrast enhancement types reported in MR imaging of breast malignancies, and first insights were gained into the relationship with tumor vascularity. PMID:26159440

  14. Southern Clouds

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03026 Southern Clouds

    This image shows a system of clouds just off the margin of the South Polar cap. Taken during the summer season, these clouds contain both water-ice and dust.

    Image information: VIS instrument. Latitude 80.2S, Longitude 57.6E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  15. Linear Clouds

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA03667 Linear Clouds

    These clouds are located near the edge of the south polar region. The cloud tops are the puffy white features in the bottom half of the image.

    Image information: VIS instrument. Latitude -80.1N, Longitude 52.1E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  16. OVRO High Resoliution Imaging of Dense Molecular Clouds in the Central Three Parsecs of the Galaxy

    NASA Astrophysics Data System (ADS)

    Christopher, M. H.; Scoville, N. Z.

    Using the Owens Valley Radio Observatory (OVRO) millimeter array, we have obtained the highest spatial (3.3" x 2.4") and spectral resolution HCN maps of the galactic center region. The prominent molecular emission comes from the circumnuclear disk (CND), a ring-like structure surrounding the galactic center at an inner radius of 1-1.5 parsecs. The CND is not a smooth structure, but rather is comprised primarily of 10-20 high density clouds with characteristic sizes of 8-10". From our observations we deduce a typical H2 density within these clouds of a few x 106 cm-3, corresponding to approximately a thousand solar masses of molecular gas in each cloud. The densities within these clouds are not high enough to prevent tidal disruption in the gravitational field of the galactic center (comprising both the massive black hole and the stellar population interior to the CND). Comparing our observed molecular gas emission with the ionized gas emission as seen in the Paschen Alpha NICMOS map from Scoville et al. (2002), there is clear evidence for interplay between the ionized and molecular gas (e.g. the western arc in ionized gas is the photoionized edge of the CND and streamers within the CND spatially and kinematically connect with the Northern Arm of ionized gas). Examining the interaction of the molecular and ionized gas within the central parsecs of the galaxy sheds observational light on conditions near massive black holes, a critical tool for understanding AGN phenomenon.

  17. Integration of Image Data for Refining Building Boundaries Derived from Point Clouds

    NASA Astrophysics Data System (ADS)

    Perera, S. N.; Hetti Arachchige, N.; Schneider, D.

    2014-08-01

    Geometrically and topologically correct 3D building models are required to satisfy with new demands such as 3D cadastre, map updating, and decision making. More attention on building reconstruction has been paid using Airborne Laser Scanning (ALS) point cloud data. The planimetric accuracy of roof outlines, including step-edges is questionable in building models derived from only point clouds. This paper presents a new approach for the detection of accurate building boundaries by merging point clouds acquired by ALS and aerial photographs. It comprises two major parts: reconstruction of initial roof models from point clouds only, and refinement of their boundaries. A shortest closed circle (graph) analysis method is employed to generate building models in the first step. Having the advantages of high reliability, this method provides reconstruction without prior knowledge of primitive building types even when complex height jumps and various types of building roof are available. The accurate position of boundaries of the initial models is determined by the integration of the edges extracted from aerial photographs. In this process, scene constraints defined based on the initial roof models are introduced as the initial roof models are representing explicit unambiguous geometries about the scene. Experiments were conducted using the ISPRS benchmark test data. Based on test results, we show that the proposed approach can reconstruct 3D building models with higher geometrical (planimetry and vertical) and topological accuracy.

  18. Ammonia Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of Ammonia Ice Clouds on Jupiter

    In this movie, put together from false-color images taken by the New Horizons Ralph instrument as the spacecraft flew past Jupiter in early 2007, show ammonia clouds (appearing as bright blue areas) as they form and disperse over five successive Jupiter 'days.' Scientists noted how the larger cloud travels along with a small, local deep hole.

  19. Scattered Brain Infarct Pattern on Diffusion-Weighted Magnetic Resonance Imaging in Patients with Acute Ischemic Stroke

    Microsoft Academic Search

    Hans-Christian Koennecke; Johannes Bernarding; Jürgen Braun; Andreas Faulstich; Chris Hofmeister; Roland Nohr; Stefanie Leistner; Peter Marx

    2001-01-01

    Background and Purpose: Infarct patterns on brain imaging contribute to the etiologic classification of ischemic stroke. However, the association of specific subtypes of infarcts and etiologic mechanisms is often weak, and acute lesions are frequently missed on initial computed tomography (CT). Diffusion-weighted imaging (DWI) is superior in visualizing acute ischemic lesions as compared to CT and conventional magnetic resonance imaging

  20. VENUS CLOUD TOPS VIEWED BY HUBBLE

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This is a NASA Hubble Space Telescope ultraviolet-light image of the planet Venus, taken on January 24 1995, when Venus was at a distance of 70.6 million miles (113.6 million kilometers) from Earth. Venus is covered with clouds made of sulfuric acid, rather than the water-vapor clouds found on Earth. These clouds permanently shroud Venus' volcanic surface, which has been radar mapped by spacecraft and from Earth-based telescope. At ultraviolet wavelengths cloud patterns become distinctive. In particular, a horizontal 'Y'-shaped cloud feature is visible near the equator. Similar features were seen from Mariner 10, Pioneer Venus, and Galileo spacecrafts. This global feature might indicate atmospheric waves, analogous to high and low pressure cells on Earth. Bright clouds toward Venus' poles appear to follow latitude lines. The polar regions are bright, possibly showing a haze of small particles overlying the main clouds. The dark regions show the location of enhanced sulfur dioxide near the cloud tops. From previous missions, astronomers know that such features travel east to west along with the Venus' prevailing winds, to make a complete circuit around the planet in four days. Because Venus is closer to the Sun than Earth, the planet appears to go through phases, like the Moon. When Venus swings close to Earth the planet's disk appears to grow in size, but changes from a full disk to a crescent. The image was taken with the Wide Field Planetary Camera-2, in PC mode. False color has been used enhance cloud features. Credit: L. Esposito (University of Colorado, Boulder), and NASA

  1. Low temperature a-Si :H photodiodes and flexible image sensor arrays patterned by digital lithography

    NASA Astrophysics Data System (ADS)

    Ng, Tse Nga; Lujan, Rene A.; Sambandan, Sanjiv; Street, Robert A.; Limb, Scott; Wong, William S.

    2007-08-01

    Hydrogenated amorphous silicon-based image sensor arrays were fabricated on polyethylene naphthalate substrates, with photodiodes optimized for process temperatures of 150°C. An optimal i-layer thickness was determined to minimize carrier recombination and to maintain sufficient light absorption and acceptable leakage current. Patterning of the thin-film transistor backplane was accomplished using ink-jet printed etch masks. A flexible image sensor is demonstrated with 75dots/in. resolution over 180×180pixels and with sensitivity of 1.2pW/cm2.

  2. Cloud Identification

    NSDL National Science Digital Library

    2012-08-03

    In this online, interactive module, students learn about the ten common cloud types and how they are formed and how to identify different cloud types on satellite images. The module is part of an online course for grades 7-12 in satellite meteorology, which includes 10 interactive modules. The site also includes lesson plans developed by teachers and links to related resources. Each module is designed to serve as a stand-alone lesson, however, a sequential approach is recommended. Designed to challenge students through the end of 12th grade, middle school teachers and students may choose to skim or skip a few sections.

  3. Efficient generation of diffraction-limited multi-sheet pattern for biological imaging.

    PubMed

    Mondal, Partha Pratim; Dilipkumar, Shilpa; Mohan, Kavya

    2015-02-15

    We demonstrate a new technique to generate multiple light-sheets for fluorescence microscopy. This is possible by illuminating the cylindrical lens using multiple copies of Gaussian beams. A diffraction grating placed just before the cylindrical lens splits the incident Gaussian beam into multiple beams traveling at different angles. Subsequently, this gives rise to diffraction-limited light-sheets after the Gaussian beams pass through the combined cylindrical lens-objective sub-system. Direct measurement of field at and around the focus of objective lens shows multi-sheet pattern with an average thickness of 7.5 ?m and inter-sheet separation of 380 ?m. Employing an independent orthogonal detection sub-system, we successfully imaged fluorescently-coated yeast cells (?4???m) encaged in agarose gel-matrix. Such a diffraction-limited sheet-pattern equipped with dedicated detection system may find immediate applications in the field of optical microscopy and fluorescence imaging. PMID:25680162

  4. The cloud imaging and particle size experiment on the aeronomy of ice in the mesosphere mission: Cloud morphology for the northern 2007 season

    Microsoft Academic Search

    D. W. Rusch; G. E. Thomas; W. McClintock; A. W. Merkel; S. M. Bailey; J. M. Russell III; C. E. Randall; C. Jeppesen; M. Callan

    2009-01-01

    The Aeronomy of Ice in the Mesosphere (AIM) mission was launched from Vandenberg Air Force Base in California at 4:26:03 EDT on April 25, 2007, becoming the first satellite mission dedicated to the study of noctilucent clouds (NLCs), also known as polar mesospheric clouds (PMC) when viewed from space. We present the first results from one of the three instruments

  5. Effect of Clouds on Optical Imaging of the Space Shuttle During the Ascent Phase: A Statistical Analysis Based on a 3D Model

    NASA Technical Reports Server (NTRS)

    Short, David A.; Lane, Robert E., Jr.; Winters, Katherine A.; Madura, John T.

    2004-01-01

    Clouds are highly effective in obscuring optical images of the Space Shuttle taken during its ascent by ground-based and airborne tracking cameras. Because the imagery is used for quick-look and post-flight engineering analysis, the Columbia Accident Investigation Board (CAIB) recommended the return-to-flight effort include an upgrade of the imaging system to enable it to obtain at least three useful views of the Shuttle from lift-off to at least solid rocket booster (SRB) separation (NASA 2003). The lifetimes of individual cloud elements capable of obscuring optical views of the Shuttle are typically 20 minutes or less. Therefore, accurately observing and forecasting cloud obscuration over an extended network of cameras poses an unprecedented challenge for the current state of observational and modeling techniques. In addition, even the best numerical simulations based on real observations will never reach "truth." In order to quantify the risk that clouds would obscure optical imagery of the Shuttle, a 3D model to calculate probabilistic risk was developed. The model was used to estimate the ability of a network of optical imaging cameras to obtain at least N simultaneous views of the Shuttle from lift-off to SRB separation in the presence of an idealized, randomized cloud field.

  6. Passive multiangle imaging of clouds, aerosols, and atmospheric dynamics: Broadening our vision from MISR to WindCam and MSPI

    NASA Astrophysics Data System (ADS)

    Diner, D. J.; Wu, D. L.; Chipman, R.; Davis, A.; Misr Science Team

    2010-12-01

    The Multi-angle Imaging SpectroRadiometer (MISR) has been collecting global Earth data from NASA’s Terra satellite since February 2000. With its nine along-track view angles, four visible/near-infrared spectral bands, intrinsic spatial resolution of 275 m, and stable calibration, no instrument that combines MISR’s attributes has previously flown in space, nor is there is a similar capability currently available on any other satellite platform. The MISR data record provides unprecedented opportunities for characterizing long-term variability in aerosol and cloud structure and atmospheric dynamics, including measurements of the vertical distributions of clouds; aerosol (smoke, volcanic, and dust) plume heights and global optical depths and particle properties; and pole-to-pole height-resolved winds. To extend what has been learned during the first decade of MISR observations, we are developing the WindCam and Multiangle SpectroPolarimetric Imager (MSPI) instruments. WindCam will enable MISR-like stereo observations over a broader swath using a much more compact sensor design. MSPI expands MISR capabilities through broader spectral coverage (ultraviolet to shortwave infrared), wider swath (enabling more rapid global coverage), and incorporation of high-accuracy polarimetric imaging, which will provide greater sensitivity to particle microphysics. A ground-based prototype camera (GroundMSPI) with spectral coverage from 355-935 nm has been built and an airborne version (AirMSPI) is ready for flight on NASA’s ER-2 high-altitude aircraft. Algorithm developments and improvements enabled by increases in computational speed since Terra launch are being explored with MISR data, and will be needed to handle the rich information content of these MISR successor instruments.

  7. Minimum description length principle in the field of image analysis and pattern recognition

    Microsoft Academic Search

    A. S. Potapov

    2011-01-01

    Problems of decision criterion in the tasks of image analysis and pattern recognition are considered. Overlearning as a practical\\u000a consequence of fundamental paradoxes in inductive inference is illustrated with examples. Theoretical (on the base of algorithmic\\u000a complexity) and practical formulations of the minimum description length (MDL) principle are given. Decrease of the overlearning\\u000a effect is shown in the examples of

  8. Discrete techniques for 3D digital images and patterns under transformations

    Microsoft Academic Search

    Zi C. Li

    1993-01-01

    Three dimensional (3-D) digital images and patterns under transformations are facilitated by the splitting-shooting method (SSM) and the splitting-integrating method (SIM). The combination (CSIM) of SSM and SIM and the combination (CIIM) of SIM and SIM are proposed for a cycle conversion T-1T, where T is a nonlinear transformation, and T-1 is its inverse transformation. This paper focuses on exploitation

  9. Comparison of point clouds derived from aerial image matching with data from airborne laser scanning. (Polish Title: Porównanie wóa?ciwo?ci chmury punktów wygenerowanej metod? dopasowania obrazów zdj?? lotniczych z danymi z lotniczego skanowania)

    NASA Astrophysics Data System (ADS)

    Dominik, W.

    2014-12-01

    The aim of this study was to investigate the properties of point clouds derived from aerial image matching and to compare them with point clouds from airborne laser scanning. A set of aerial images acquired in years 2010-2013 over the city of Elblag were used for the analysis. Images were acquired with the use of three digital cameras: DMC II 230, DMC I and DigiCAM60 with a GSD varying from 4.5 cm to 15 cm. Eight sets of images that were used in the study were acquired at different stages of the growing season - from March to December. Two LiDAR point clouds were used for the comparison - one with a density of 1.3 p/m2 and a second with a density of 10 p/m2. Based on the input images point clouds were created with the use of the semi-global matching method. The properties of the obtained point clouds were analyzed in three ways: - by the comparison of the vertical accuracy of point clouds with reference to a terrain profile surveyed on bare ground with GPS-RTK method - by visual assessment of point cloud profiles generated both from SGM and LiDAR point clouds - by visual assessment of a digital surface model generated from a SGM point cloud with reference to a digital surface model generated from a LiDAR point cloud. The conducted studies allowed a number of observations about the quality of SGM point clouds to be formulated with respect to different factors. The main factors having influence on the quality of SGM point clouds are GSD and base/height ratio. The essential problem related to SGM point clouds are areas covered with vegetation where SGM point clouds are visibly worse in terms of both accuracy and the representation of terrain surface. It is difficult to expect that in these areas SGM point clouds could replace LiDAR point clouds. This leads to a general conclusion that SGM point clouds are less reliable, more unpredictable and are dependent on more factors than LiDAR point clouds. Nevertheless, SGM point clouds generated with appropriate parameters can have better accuracy than LiDAR point clouds and present more detailed information about the terrain surface.

  10. Remote sensing of cloud, aerosol, and water vapor properties from the moderate resolution imaging spectrometer (MODIS)

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Kaufman, Yoram J.; Menzel, W. Paul; Tanre, Didier D.

    1992-01-01

    The authors describe the status of MODIS-N and its companion instrument MODIS-T (tilt), a tiltable cross-track scanning spectrometer with 32 uniformly spaced channels between 0.410 and 0.875 micron. They review the various methods being developed for the remote sensing of atmospheric properties using MODIS, placing primary emphasis on the principal atmospheric applications of determining the optical, microphysical, and physical properties of clouds and aerosol particles from spectral reflection and thermal emission measurements. In addition to cloud and aerosol properties, MODIS-N will be used for determining the total precipitable water vapor and atmospheric stability. The physical principles behind the determination of each of these atmospheric products are described, together with an example of their application to aircraft and/or satellite measurements.

  11. Requirements and Implementation Feasibility for a CubeSat Thermal Infrared Imaging System to Monitor the Structure of Volcanic Ash Clouds

    NASA Astrophysics Data System (ADS)

    Thorsen, D.; Carroll, R.; Webley, P.; Hawkins, J.

    2014-12-01

    The 2010 eruption of the Eyjafjallajökull volcano in Iceland caused the cancellation of approximately 108,000 flights over an 8-day period, disrupted air traffic worldwide, and cost the airline industry more than $400 million per day. The inconvenience and economic impact of this and similar events, such as Puyehue-Cordon-Caulle in 2011, have heightened the interest in developing improved satellite remote sensing techniques for monitoring volcanic plumes and drifting clouds. For aviation safety, the operational/research community has started to move towards classifying the concentrations within volcanic plumes and clouds. Additionally, volcanic ash transport and dispersion (VATD) models are often used for forecasting ash cloud locations and they require knowledge of the structure of the erupting column to improve their ash simulations and also downwind 3-D maps of the ash cloud to calibrate/validate their modeling output. Existing remote sensing satellites utilize a brightness temperature method with thermal infrared (TIR) measurements from 10 - 12 ?m to determine mass loading of volcanic ash along a single line of sight, but they have infrequent revisit times and they cannot resolve the three-dimensional structure of the ash clouds. A cluster of CubeSats dedicated to the monitoring of volcanic ash and plumes could provide both more frequent updates and the multi-aspect images needed to resolve the density structure of volcanic ash clouds and plumes. In this presentation, we discuss the feasibility and requirements for a CubeSat TIR imaging system and the associated on-board image processing that would be required to monitor the structure of volcanic ash clouds from Low Earth Orbit.

  12. Near-field imaging of neurotransmitter release and uptake in patterned neuron networks

    NASA Astrophysics Data System (ADS)

    Degenaar, Patrick; Murakami, Yuji; Yokoyama, Kenji; Tamiya, Eiichi; Le Pioufle, Bruno; Fujita, Yiroyuki

    2000-04-01

    A SNOAM system is capable of obtaining simultaneous topographic and optical images with a resolution beyond than the diffraction limit of far field optical imaging. Fluorescence tagging combined with optical resolutions of better than 100nm allow us to detect structures not possible with conventional microscopes. Also in contrast with electron microscopy SNOAM has the ability to look at biological structures in the liquid medium. Presently there is much interest in understanding the processes that lead to LTP in neuron synapses. LTP is widely associated with memory function in neurons. Hence, better understanding will lead to advances in medicine, as well as neuron-based memory and processing devices. Better understanding is also crucial to the development of neuron-electronic interfaces. In this research, neuron networks are grown on a patterned polylysine substrate. Polylysine is patterned using micro lithographic techniques. Neurons are extracted from the hippocampus of chick embryos, and are then grown on this pattern under standard sterile incubating conditions. The neurons are stimulated to release the neurotransmitter glutamate. The glutamate is then fluorescently imaged with Amplex-red SNOAM.

  13. Three-dimensional point cloud alignment detecting fiducial markers by structured light stereo imaging

    Microsoft Academic Search

    Sandro Barone; Alessandro Paoli; Armando Viviano Razionale

    In recent years, various methodologies of shape reconstruction have been proposed with the aim at creating Computer-Aided\\u000a Design models by digitising physical objects using optical sensors. Generally, the acquisition of 3D geometrical data includes\\u000a crucial tasks, such as planning scanning strategies and aligning different point clouds by multiple view approaches, which\\u000a differ for user’s interaction and hardware cost. This paper

  14. Cloud computing platform for GIS image processing in U-city

    Microsoft Academic Search

    Jong Won Park; Chang Ho Yun; Shin-gyu Kim; Heon Y. Yeom; Yong Woo Lee

    2011-01-01

    Ubiquitous city (U-city) is a city with ubiquitous information technology that enables citizens to access the converged information anywhere and anytime. A lot of compute power are required in U-city, because large amount of data should be processed in real-time. Cloud computing enables users to use the abstracted and virtualized computing resources and to process huge amount of information without

  15. Multi-line spectral imaging of dense cores in the Lupus molecular cloud

    E-print Network

    Benedettini, Milena; Burton, Micheal G; Viti, Serena; Molinari, Sergio; Caselli, Paola; Testi, Leonardo

    2011-01-01

    The molecular clouds Lupus 1, 3 and 4 were mapped with the Mopra telescope at 3 and 12 mm. Emission lines from high density molecular tracers were detected, i.e. NH$_3$ (1,1), NH$_3$ (2,2), N$_2$H$^+$ (1-0), HC$_3$N (3-2), HC$_3$N (10-9), CS (2-1), CH$_3$OH (2$_0-1_0$)A$^+$ and CH$_3$OH (2$_{-1}-1_{-1}$)E. Velocity gradients of more than 1 km s$^{-1}$ are present in Lupus 1 and 3 and multiple gas components are present in these clouds along some lines of sight. Lupus 1 is the cloud richest in high density cores, 8 cores were detected in it, 5 cores were detected in Lupus 3 and only 2 in Lupus 4. The intensity of the three species HC$_3$N, NH$_3$ and N$_2$H$^+$ changes significantly in the various cores: cores that are brighter in HC$_3$N are fainter or undetected in NH$_3$ and N$_2$H$^+$ and vice versa. We found that the column density ratios HC$_3$N/N$_2$H$^+$ and HC$_3$N/NH$_3$ change by one order of magnitude between the cores, indicating that also the chemical abundance of these species is different. The ...

  16. Distributed Storage Algorithm for Geospatial Image Data Based on Data Access Patterns

    PubMed Central

    Pan, Shaoming; Li, Yongkai; Xu, Zhengquan; Chong, Yanwen

    2015-01-01

    Declustering techniques are widely used in distributed environments to reduce query response time through parallel I/O by splitting large files into several small blocks and then distributing those blocks among multiple storage nodes. Unfortunately, however, many small geospatial image data files cannot be further split for distributed storage. In this paper, we propose a complete theoretical system for the distributed storage of small geospatial image data files based on mining the access patterns of geospatial image data using their historical access log information. First, an algorithm is developed to construct an access correlation matrix based on the analysis of the log information, which reveals the patterns of access to the geospatial image data. Then, a practical heuristic algorithm is developed to determine a reasonable solution based on the access correlation matrix. Finally, a number of comparative experiments are presented, demonstrating that our algorithm displays a higher total parallel access probability than those of other algorithms by approximately 10–15% and that the performance can be further improved by more than 20% by simultaneously applying a copy storage strategy. These experiments show that the algorithm can be applied in distributed environments to help realize parallel I/O and thereby improve system performance. PMID:26181628

  17. Laser direct imaging of high density patterns on PCB covered by photoresist

    NASA Astrophysics Data System (ADS)

    Barbucha, R.; Kocik, M.; Mizeraczyk, J.; Koziol, G.; Borecki, J.

    2007-03-01

    The increasing demands for miniaturization and better functionality of electronic components and devices have a significant effect on the requirements facing the printed circuit board (PCB) industry. PCB manufactures are driving for producing high density interconnect (HDI) boards at significantly reduced cost and reduced implementation time. The interconnection complexity of the PCB is still growing and today calls for 50/50 ?m or 25/25 ?m technology are real. Existing technologies are unable to offer acceptable solution. Recently the Laser Direct Imaging (LDI) technology is considered as an answer for these challenges. LDI is a process of imaging electric circuits directly on PCB without the use of a phototool or mask. The exposure of the photo-sensitive resist is carried out using a laser beam that is scanned across photoresist surface and switched on and off by means of a computer control system according to the electrical circuit pattern. Usually the laser used in the LDI generates a UV line, which is suitable to the commonly available photoresists. In this paper we present the laboratory system for Laser Direct Imaging and also the recent results on imaging the circuitry pattern on the PCB covered by a photosensitive resist.

  18. Dark-field illuminated fiber bundle endoscopy with iterative l1-min image reconstruction for honeycomb pattern removal

    NASA Astrophysics Data System (ADS)

    Liu, Xuan; Zhang, Lijun; Kirby, Mitchell; Raj, Divyaansh; Qi, Shaohai; Zhao, Feng

    2015-03-01

    In this study, we developed a dark-field illuminated reflectance fiber-optic microscope (DRFM) along with an algorithm for l1-norm minimization of fiber bundle image to provide intrinsic endoscopic imaging with cellular resolution. To suppress specular reflection from fiber bundle facets, we adopted a dark-field configuration. To remove the honeycomb pattern of fiber bundle while preserve image resolution and contrast, we chose to minimize the image l1 norm using iterative shrinkage thresholding (IST) algorithm.

  19. Analysis of speckle patterns in phase-contrast images of lung tissue

    NASA Astrophysics Data System (ADS)

    Kitchen, M. J.; Paganin, D.; Lewis, R. A.; Yagi, N.; Uesugi, K.

    2005-08-01

    Propagation-based phase-contrast images of mice lungs have been obtained at the SPring-8 synchrotron research facility. Such images exhibit a speckled intensity pattern that bears a superficial resemblance to alveolar structures. This speckle results from focussing effects as projected air-filled alveoli form aberrated compound refractive lenses. An appropriate phase-retrieval algorithm has been utilized to reconstruct the approximate projected lung tissue thickness from single-phase-contrast mice chest radiographs. The results show projected density variations across the lung, highlighting regions of low density corresponding to air-filled regions. Potentially, this offers a better method than conventional radiography for detecting lung diseases such as fibrosis, emphysema and cancer, though this has yet to be demonstrated. As such, the approach can assist in continuing studies of lung function utilizing propagation-based phase-contrast imaging.

  20. Pattern recognition system invariant to rotation and scale to identify color images

    NASA Astrophysics Data System (ADS)

    Coronel-Beltrán, Angel

    2014-10-01

    This work presents a pattern recognition digital system based on nonlinear correlations. The correlation peak values given by the system were analyzed by the peak-to-correlation energy (PCE) metric to determine the optimal value of the non-linear coefficient kin the k-law. The system was tested with 18 different color images of butterflies; each image was rotated from 0° to 180° with increments of 1° and scaled ±25% with increments of 1% and to take advantage of the color property of the images the RGB model was employed. The boxplot statistical analysis of the mean with ±2*EE (standard errors) for the PCE values set that the system invariant to rotation and scale has a confidence level at least of 95.4%.

  1. Waves on White: Ice or Clouds?

    NASA Technical Reports Server (NTRS)

    2005-01-01

    As it passed over Antarctica on December 16, 2004, the Multi-angle Imaging SpectroRadiometer (MISR) on NASA's Terra satellite captured this image showing a wavy pattern in a field of white. At most other latitudes, such wavy patterns would likely indicate stratus or stratocumulus clouds. MISR, however, saw something different. By using information from several of its multiple cameras (each of which views the Earth's surface from a different angle), MISR was able to tell that what looked like a wavy cloud pattern was actually a wavy pattern on the ice surface. One of MISR's cloud classification products, the Angular Signature Cloud Mask (ASCM), correctly identified the rippled area as being at the surface.

    In this image pair, the view from MISR's most oblique backward-viewing camera is on the left, and the color-coded image on the right shows the results of the ASCM. The colors represent the level of certainty in the classification. Areas that were classed as cloudy with high confidence are white, and areas where the confidence was lower are yellow; dark blue shows confidently clear areas, while light blue indicates clear with lower confidence. The ASCM works particularly well at detecting clouds over snow and ice, but also works well over ocean and land. The rippled area on the surface which could have been mistaken for clouds are actually sastrugi -- long wavelike ridges of snow formed by the wind and found on the polar plains. Usually sastrugi are only several centimeters high and several meters apart, but large portions of East Antarctica are covered by mega-sastrugi ice fields, with dune-like features as high as four meters separated by two to five kilometers. The mega-sastrugi fields are a result of unusual snow accumulation and redistribution processes influenced by the prevailing winds and climate conditions. MISR imagery indicates that these mega sastrugi were stationary features between 2002 and 2004.

    Being able to distinguish clouds from snow or ice-covered surfaces is important in order to adequately characterize the radiation balance of the polar regions. However, detecting clouds using spaceborne detectors over snow and ice surfaces is notoriously difficult, because the surface may often be as bright and as cold as the overlying clouds, and because polar atmospheric temperature inversions sometimes mean that clouds are warmer than the underlying snow or ice surface. The Angular Signature Cloud Mask (ASCM) was developed based on the Band-Differenced Angular Signature (BDAS) approach, introduced by Di Girolamo and Davies (1994) and updated for MISR application by Di Girolamo and Wilson (2003). BDAS uses both spectral and angular changes in reflectivity to distinguish clouds from the background, and the ASCM calculates the difference between the 446 and 866 nanometer reflectances at MISR's two most oblique cameras that view forward-scattered light. New land thresholds for the ASCM are planned for delivery later this year.

    The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82o north and 82o south latitude. This image area covers about 277 kilometers by 421 kilometers in the interior of the East Antarctic ice sheet. These data products were generated from a portion of the imagery acquired during Terra orbit 26584 and utilize data from within blocks 159 to 161 within World Reference System-2 path 63.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

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

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2008-01-01

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

  4. Neuropsychological patterns in magnetic resonance imaging-defined subgroups of patients with degenerative dementia

    PubMed Central

    LISTERUD, JOHN; POWERS, CHIVON; MOORE, PEACHIE; LIBON, DAVID J.; GROSSMAN, MURRAY

    2010-01-01

    We hypothesized that specific neuropsychological deficits were associated with specific patterns of atrophy. A magnetic resonance imaging volumetric study and a neuropsychological protocol were obtained for patients with several frontotemporal lobar dementia phenotypes including a social/dysexecutive (SOC/EXEC, n = 17), progressive nonfluent aphasia (n = 9), semantic dementia (n = 7), corticobasal syndrome (n = 9), and Alzheimer’s disease (n = 21). Blinded to testing results, patients were partitioned according to pattern of predominant cortical atrophy; our partitioning algorithm had been derived using seriation, a hierarchical classification technique. Neuropsychological test scores were regressed versus these atrophy patterns as fixed effects using the covariate total atrophy as marker for disease severity. The results showed the model accounted for substantial variance. Furthermore, the “large-scale networks” associated with each neuropsychological test conformed well to the known literature. For example, bilateral prefrontal cortical atrophy was exclusively associated with SOC/EXEC dysfunction. The neuropsychological principle of “double dissociation” was supported not just by such active associations but also by the “silence” of locations not previously implicated by the literature. We conclude that classifying patients with degenerative dementia by specific pattern of cortical atrophy has the potential to predict individual patterns of cognitive deficits. PMID:19402932

  5. Introduction to Clouds

    NSDL National Science Digital Library

    George Tselioudis

    1997-01-01

    This site provides the user an opportunity to explore storm clouds and climate change through the use of NASA climate research data obtained through satellite imaging. The user is challenged to investigate actual scientific research data on clouds and storms, and make observations and interpretations available to NASA research scientists for review. Topics addressed by these investigations include the role of clouds in relation to the changing climate of Earth, the role of clouds in warming or cooling the planet, and the major types of clouds produced by storms.

  6. Cloud Computing Service for Managing Large Medical Image Data-Sets Using Balanced Collaborative Agents

    Microsoft Academic Search

    Raúl Alonso-Calvo; José Crespo; Victor Maojo; Alberto Muñoz; Miguel García-Remesal; David Pérez-Rey

    2011-01-01

    \\u000a Managing large medical image collections is an increasingly demanding important issue in many hospitals and other medical\\u000a settings. A huge amount of this information is daily generated, which requires robust and agile systems. In this paper we\\u000a present a distributed multi-agent system capable of managing very large medical image datasets. In this approach, agents extract\\u000a low-level information from images and

  7. Constraining mass-diameter relations from hydrometeor images and cloud radar reflectivities in tropical continental and oceanic convective anvils

    NASA Astrophysics Data System (ADS)

    Fontaine, E.; Schwarzenboeck, A.; Delanoë, J.; Wobrock, W.; Leroy, D.; Dupuy, R.; Gourbeyre, C.; Protat, A.

    2014-10-01

    In this study the density of ice hydrometeors in tropical clouds is derived from a combined analysis of particle images from 2-D-array probes and associated reflectivities measured with a Doppler cloud radar on the same research aircraft. Usually, the mass-diameter m(D) relationship is formulated as a power law with two unknown coefficients (pre-factor, exponent) that need to be constrained from complementary information on hydrometeors, where absolute ice density measurement methods do not apply. Here, at first an extended theoretical study of numerous hydrometeor shapes simulated in 3-D and arbitrarily projected on a 2-D plan allowed to constrain the exponent ?of the m(D) relationship from the exponent ? of the surface-diameterS(D)relationship, which is likewise written as a power law. Since S(D) always can be determined for real data from 2-D optical array probes or other particle imagers, the evolution of the m(D) exponent can be calculated. After that, the pre-factor ? of m(D) is constrained from theoretical simulations of the radar reflectivities matching the measured reflectivities along the aircraft trajectory. The study was performed as part of the Megha-Tropiques satellite project, where two types of mesoscale convective systems (MCS) were investigated: (i) above the African continent and (ii) above the Indian Ocean. For the two data sets, two parameterizations are derived to calculate the vertical variability of m(D) coefficients ? and ? as a function of the temperature. Originally calculated (with T-matrix) and also subsequently parameterized m(D) relationships from this study are compared to other methods (from literature) of calculating m(D) in tropical convection. The significant benefit of using variable m(D) relations instead of a single m(D) relationship is demonstrated from the impact of all these m(D) relations on Z-CWC (Condensed Water Content) and Z-CWC-T-fitted parameterizations.

  8. Cloud tracking by scale space classification

    Microsoft Academic Search

    Dipti Prasad Mukherjee; Scott T. Acton

    2002-01-01

    The problem of cloud tracking within a sequence of geo-stationary satellite images has direct relevance to the analysis of cloud life cycles and to the detection of cloud motion vectors (CMVs). The proposed approach first identifies a homogeneous consistent cloud mass for tracking and then establishes motion correspondence within an image sequence. In contrast to the crosscorrelation based approach as

  9. Crater Clouds

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA06085 Crater Clouds

    The crater on the right side of this image is affecting the local wind regime. Note the bright line of clouds streaming off the north rim of the crater.

    Image information: VIS instrument. Latitude -78.8N, Longitude 320.0E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  10. Laser direct imaging of high-density interconnect patterns on PCB

    NASA Astrophysics Data System (ADS)

    Barbucha, R.; Kocik, M.; Mizeraczyk, J.; Kozio?, G.; Borecki, J.

    2006-12-01

    The increasing demands for miniaturization of electronic components and devices is observed. This caused a significant effect on the requirements faced on the printed circuit board (PCB) industry. PCB manufactures are driving for producing high density interconnect (HDI) boards at significantly reduced cost and reduced implementation time. The interconnection complexity of the PCB is still growing and today calls for 50/50 ?m or 25/25 ?m technology are real. Existing technologies, e.g. photolithograpy, are unable to offer such resolution. Laser Direct Imaging (LDI) technology is considered as an answer for these challenges. LDI is a process of imaging electric circuits directly on PCB without the use of a mask. The exposure of the photo-sensitive resist is carried out using a laser beam that is scanned across photoresist surface and switched on and off by means of a computer control system according to the electrical circuit pattern. Usually the laser used in the LDI generates a UV line, which is suitable to the commonly available photoresists. In this paper we present our recent results on the use a UV Nd:YAG laser (?=355 nm) for direct imaging the circuitry pattern on the PCB covered by a photosensitive resist.

  11. EUV pattern defect detection sensitivity based on aerial image linewidth measurements

    SciTech Connect

    Goldberg, K. A.; Mochi, I.; Naulleau, P.; Liang, T.; Yan, P.-Y.; Huh, S.

    2010-02-12

    As the quality of EUV-wavelength mask inspection microscopes improves over time, the image properties and intensity profiles of reflected light can be evaluated in ever-greater detail. The SEMATECH Berkeley Actinic Inspection Tool (AIT) is one such microscope, featuring mask resolution values that match or exceed those available through lithographic printing in current photoresists. In order to evaluate the defect detection sensitivity of the AIT for dense line patterns on typical masks, the authors study the line width roughness (LWR) on two masks, as measured in the EUV images. They report the through-focus and pitch dependence of contrast, image log slope, linewidth, and LWR. The AIT currently reaches LWR 3{sigma} values close to 9 nm for 175 nm half-pitch lines. This value is below 10% linewidth for nearly all lines routinely measured in the AIT. Evidence suggests that this lower level may arise from the mask's inherent pattern roughness. While the sensitivity limit of the AlT has not yet been established, it is clear that the AIT has the required sensitivity to detect defects that cause 10% linewidth changes in line sizes of 125 nm and larger.

  12. Dark Current Characterization of the CMOS APS Imagers with Test Patterns Fabricated Using a 0.18 CMOS Technology

    E-print Network

    Lee, Jong Duk

    #12;Dark Current Characterization of the CMOS APS Imagers with Test Patterns Fabricated Using a 0 been investigated in the CMOS APS with test patterns fabricated with the 0.18 CMOS technology. We sensors (APS), fabricated using a standard CMOS process, have advantages of low power consumption, low

  13. The Spitzer Survey of the Small Magellanic Cloud: S3MC Imaging and Photometry in the Mid and Far-Infrared Wavebands

    Microsoft Academic Search

    Alberto D. Bolatto; Joshua D. Simon; Sneÿzana Stanimirovi ´ c; Ronak Y. Shah; Kim Venn; Adam K. Leroy; Karin Sandstrom; James M. Jackson; Frank P. Israel; Aigen Li; Lister Staveley-Smith; Caroline Bot; Francois Boulanger; Monica Rubio

    2006-01-01

    We present the initial results from the Spitzer Survey of the Small\\u000aMagellanic Cloud (S3MC), which imaged the star-forming body of the Small\\u000aMagellanic Cloud (SMC) in all seven MIPS and IRAC wavebands. We find that the\\u000aF_8\\/F_24 ratio (an estimate of PAH abundance) has large spatial variations and\\u000atakes a wide range of values that are unrelated to metallicity

  14. Global ice cloud observations: radiative properties and statistics from moderate-resolution imaging spectroradiometer measurements

    E-print Network

    Meyer, Kerry Glynne

    2009-05-15

    of microphysical and optical properties, as well as determining the radiative impact. Perhaps one of the most recognized instruments used for such research is the Moderate-resolution Imaging Spectroradiometer (MODIS), carried aboard the NASA EOS satellites Terra...

  15. Global ice cloud observations: radiative properties and statistics from moderate-resolution imaging spectroradiometer measurements 

    E-print Network

    Meyer, Kerry Glynne

    2009-05-15

    of microphysical and optical properties, as well as determining the radiative impact. Perhaps one of the most recognized instruments used for such research is the Moderate-resolution Imaging Spectroradiometer (MODIS), carried aboard the NASA EOS satellites Terra...

  16. Patterns of intersecting fiber arrays revealed in whole muscle with generalized q-space imaging.

    PubMed

    Taylor, Erik N; Hoffman, Matthew P; Aninwene, George E; Gilbert, Richard J

    2015-06-01

    The multiscale attributes of mammalian muscle confer significant challenges for structural imaging in vivo. To achieve this, we employed a magnetic resonance method, termed "generalized Q-space imaging", that considers the effect of spatially distributed diffusion-weighted magnetic field gradients and diffusion sensitivities on the morphology of Q-space. This approach results in a subvoxel scaled probability distribution function whose shape correlates with local fiber orientation. The principal fiber populations identified within these probability distribution functions can then be associated by streamline methods to create multivoxel tractlike constructs that depict the macroscale orientation of myofiber arrays. We performed a simulation of Q-space input parameters, including magnetic field gradient strength and direction, diffusion sensitivity, and diffusional sampling to determine the optimal achievable fiber angle separation in the minimum scan time. We applied this approach to resolve intravoxel crossing myofiber arrays in the setting of the human tongue, an organ with anatomic complexity based on the presence of hierarchical arrays of intersecting myocytes. Using parameters defined by simulation, we imaged at 3T the fanlike configuration of the human genioglossus and the laterally positioned merging fibers of the styloglossus, inferior longitudinalis, chondroglossus, and verticalis. Comparative scans of the excised mouse tongue at 7T demonstrated similar midline and lateral crossing fiber patterns, whereas histological analysis confirmed the presence and distribution of these myofiber arrays at the microscopic scale. Our results demonstrate a magnetic resonance method for acquiring and displaying diffusional data that defines highly ordered myofiber patterns in architecturally complex tissue. Such patterns suggest inherent multiscale fiber organization and provide a basis for structure-function analyses in vivo and in model tissues. PMID:26039175

  17. A sparse representation-based algorithm for pattern localization in brain imaging data analysis.

    PubMed

    Li, Yuanqing; Long, Jinyi; He, Lin; Lu, Haidong; Gu, Zhenghui; Sun, Pei

    2012-01-01

    Considering the two-class classification problem in brain imaging data analysis, we propose a sparse representation-based multi-variate pattern analysis (MVPA) algorithm to localize brain activation patterns corresponding to different stimulus classes/brain states respectively. Feature selection can be modeled as a sparse representation (or sparse regression) problem. Such technique has been successfully applied to voxel selection in fMRI data analysis. However, single selection based on sparse representation or other methods is prone to obtain a subset of the most informative features rather than all. Herein, our proposed algorithm recursively eliminates informative features selected by a sparse regression method until the decoding accuracy based on the remaining features drops to a threshold close to chance level. In this way, the resultant feature set including all the identified features is expected to involve all the informative features for discrimination. According to the signs of the sparse regression weights, these selected features are separated into two sets corresponding to two stimulus classes/brain states. Next, in order to remove irrelevant/noisy features in the two selected feature sets, we perform a nonparametric permutation test at the individual subject level or the group level. In data analysis, we verified our algorithm with a toy data set and an intrinsic signal optical imaging data set. The results show that our algorithm has accurately localized two class-related patterns. As an application example, we used our algorithm on a functional magnetic resonance imaging (fMRI) data set. Two sets of informative voxels, corresponding to two semantic categories (i.e., "old people" and "young people"), respectively, are obtained in the human brain. PMID:23227167

  18. Parameter Estimation of Fossil Oysters from High Resolution 3D Point Cloud and Image Data

    NASA Astrophysics Data System (ADS)

    Djuricic, Ana; Harzhauser, Mathias; Dorninger, Peter; Nothegger, Clemens; Mandic, Oleg; Székely, Balázs; Molnár, Gábor; Pfeifer, Norbert

    2014-05-01

    A unique fossil oyster reef was excavated at Stetten in Lower Austria, which is also the highlight of the geo-edutainment park 'Fossilienwelt Weinviertel'. It provides the rare opportunity to study the Early Miocene flora and fauna of the Central Paratethys Sea. The site presents the world's largest fossil oyster biostrome formed about 16.5 million years ago in a tropical estuary of the Korneuburg Basin. About 15,000 up to 80-cm-long shells of Crassostrea gryphoides cover a 400 m2 large area. Our project 'Smart-Geology for the World's largest fossil oyster reef' combines methods of photogrammetry, geology and paleontology to document, evaluate and quantify the shell bed. This interdisciplinary approach will be applied to test hypotheses on the genesis of the taphocenosis (e.g.: tsunami versus major storm) and to reconstruct pre- and post-event processes. Hence, we are focusing on using visualization technologies from photogrammetry in geology and paleontology in order to develop new methods for automatic and objective evaluation of 3D point clouds. These will be studied on the basis of a very dense surface reconstruction of the oyster reef. 'Smart Geology', as extension of the classic discipline, exploits massive data, automatic interpretation, and visualization. Photogrammetry provides the tools for surface acquisition and objective, automated interpretation. We also want to stress the economic aspect of using automatic shape detection in paleontology, which saves manpower and increases efficiency during the monitoring and evaluation process. Currently, there are many well known algorithms for 3D shape detection of certain objects. We are using dense 3D laser scanning data from an instrument utilizing the phase shift measuring principle, which provides accurate geometrical basis < 3 mm. However, the situation is difficult in this multiple object scenario where more than 15,000 complete or fragmentary parts of an object with random orientation are found. The goal is to investigate if the application of state-of-the-art 3D digitizing, data processing, and visualization technologies support the interpretation of this paleontological site. The obtained 3D data (approx. 1 billion points at the respective area) is analyzed with respect to their 3D structure in order to derive geometrical information. The aim of this contribution is to segment the 3D point cloud of laser scanning data into meaningful regions representing particular objects. Geometric parameters (curvature, tangent plane orientation, local minimum and maximum, etc.) are derived for every 3D point of the point cloud. A set of features is computed in each point using different kernel sizes to define neighborhoods of different size. This provides information on convexity (outer surface), concavity (inner surface) and locally flat areas, which shall be further utilized in fitting model of Crassostrea-shells. In addition, digitizing is performed manually in order to obtain a representative set of reference data for the evaluation of the obtained results. For evaluating these results the reference data (length and orientation of specimen) is then compared to the automatically derived segments of the point cloud. The study is supported by the Austrian Science Fund (FWF P 25883-N29).

  19. IR Thermal Imaging Device using Photo-Patternable Temperature Sensitive Paint

    NASA Astrophysics Data System (ADS)

    Tsukamoto, T.; Wang, M.; Tanaka, S.

    2014-11-01

    This paper reports an infrared-to-visible transducer array made of temperature sensitive paint (TSP) for low-cost thermal imaging application. A novel fabrication process using a photo-patternable temperature sensitive paint (PTSP) combined with an SU-8 transfer method was developed. The developped process is simpler than before, and prevents the TSP structure from plasma-induced damage and sticking across a sacrificially-etched gap. The selfsuspended structure as small as 100 pm was successfully fabricated with a large gap of 40 ?m from the substrate. The heated object of 300°C was detected with a resolution of about 0.4 mm.

  20. A preliminary computer pattern analysis of satellite images of mature extratropical cyclones

    NASA Technical Reports Server (NTRS)

    Burfeind, Craig R.; Weinman, James A.; Barkstrom, Bruce R.

    1987-01-01

    This study has applied computerized pattern analysis techniques to the location and classification of features of several mature extratropical cyclones that were depicted in GOES satellite images. These features include the location of the center of the cyclone vortex core and the location of the associated occluded front. The cyclone type was classified in accord with the scheme of Troup and Streten. The present analysis was implemented on a personal computer; results were obtained within approximately one or two minutes without the intervention of an analyst.

  1. Numerical simulations of the three-dimensional distribution of polar mesospheric clouds and comparisons with Cloud Imaging and Particle Size (CIPS) experiment and the Solar Occultation For Ice Experiment (SOFIE) observations

    NASA Astrophysics Data System (ADS)

    Bardeen, C. G.; Toon, O. B.; Jensen, E. J.; Hervig, M. E.; Randall, C. E.; Benze, S.; Marsh, D. R.; Merkel, A.

    2010-05-01

    Polar mesospheric clouds (PMC) routinely form in the cold summer mesopause region when water vapor condenses to form ice. We use a three-dimensional chemistry-climate model based on the Whole-Atmosphere Community Climate Model (WACCM) with sectional microphysics from the Community Aerosol and Radiation Model for Atmospheres (CARMA) to study the distribution and characteristics of PMCs formed by heterogeneous nucleation of water vapor onto meteoric smoke particles. We find good agreement between these simulations and cloud properties for the Northern Hemisphere in 2007 retrieved from the Solar Occultation for Ice Experiment (SOFIE) and the Cloud Imaging and Particle Size (CIPS) experiment from the Aeronomy of Ice in the Mesosphere (AIM) mission. The main discrepancy is that simulated ice number densities are less than those retrieved by SOFIE. This discrepancy may indicate an underprediction of nucleation rates in the model, the lack of small-scale gravity waves in the model, or a bias in the SOFIE results. The WACCM/CARMA simulations are not very sensitive to large changes in the barrier to heterogeneous nucleation, which suggests that large supersaturations in the model nucleate smaller meteoric smoke particles than are traditionally assumed. Our simulations are very sensitive to the temperature structure of the summer mesopause, which in the model is largely dependent upon vertically propagating gravity waves that reach the mesopause region, break, and deposit momentum. We find that cloud radiative heating is important, with heating rates of up to 8 K/d.

  2. Automatic analysis of stereoscopic GOES/GOES and GOES/NOAA image pairs for measurement of hurricane cloud top height and structure

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Strong, J.; Pierce, H.; Woodward, R. H.

    1989-01-01

    Results are presented from a baseline study using an synthetic stereo image pair to test the Automatic Stereo Analysis (ASA) technique for reproducing cloud top structure. The ASA analysis, display, and calibration procedures are described. A GEO/LEO (GOES/NOAA AVHRR) image pair from Hurrican Allen in 1980 is used to illustrate the results that can be obtained using the ASA technique. Also, results are presented from applying the ASA technique to a GEO/GEO (GOES/GOES) image pair of Hurricane Gilbert in 1988.

  3. VLA Imaging of the Intriguing HI Cloud HIJASS J1021+6842 in the M81 Group

    E-print Network

    F. Walter; E. Skillman; E. Brinks

    2005-06-02

    We present VLA HI 21cm observations of HIJASS J1021+6842 which has been discovered in the direction of the M81 group. Our synthesis imaging reveals that the HI is distributed over a larger angular extent and velocity range than the single dish discovery observations. Assuming that HIJASS J1021+6842 is at the distance of the M81 group, we detect 1.5 x 10^8 M_sun of HI distributed over as much as 30 kpc, i.e., substantially larger than the biggest dwarf galaxies in the same group. At the depth of our imaging, the HI appears to be confined to at least 7 clouds. Peak HI column densities are ~1.8 x 10^20 atoms cm^-2 which is well below the canonical star formation threshold of ~10^21 atoms cm^-2 and therefore consistent with the fact that no optical counterpart has as yet been identified. A gradient in velocity is observed across the extent of the detected HI; assuming that the object is gravitationally bound we derive a dynamical mass of 7 x 10^9 M_sun and a dark-to-luminous mass ratio of >10. Alternatively, a tidal origin may also result in the observed velocity gradient which would lead to a considerably lower dynamical mass. Given the above properties and the absence of evidence of a stellar population, HIJASS J1021+6842 is unique amongst the other systems in the M81 group.

  4. Joint segmentation of images and scanned point cloud in large-scale street scenes with low-annotation cost.

    PubMed

    Zhang, Honghui; Wang, Jinglu; Fang, Tian; Quan, Long

    2014-11-01

    We propose a novel method for the parsing of images and scanned point cloud in large-scale street environment. The proposed method significantly reduces the intensive labeling cost in previous works by automatically generating training data from the input data. The automatic generation of training data begins with the initialization of training data with weak priors in the street environment, followed by a filtering scheme to remove mislabeled training samples. We formulate the filtering as a binary labeling optimization problem over a conditional random filed that we call object graph, simultaneously integrating spatial smoothness preference and label consistency between 2D and 3D. Toward the final parsing, with the automatically generated training data, a CRF-based parsing method that integrates the coordination of image appearance and 3D geometry is adopted to perform the parsing of large-scale street scenes. The proposed approach is evaluated on city-scale Google Street View data, with an encouraging parsing performance demonstrated. PMID:25148662

  5. Study of combined filter based on wavelet transform to denoise stripe images of electronic speckle shearography pattern interferometry

    NASA Astrophysics Data System (ADS)

    Liu, Zhongling; Jing, Chao; Zhang, Yimo

    2011-11-01

    Stripe images of electronic speckle shearography pattern interferometry, in which stripe distribution are correlated with vertical micro distortion or micro vibration of objects, are severely disturbed by noises, and so denoising stripe images of electronic speckle shearography pattern interferometry is necessary to extract useful stripe distribution information. Denoising methods and flow for stripe images of electronic speckle shearography pattern interferometry are analyzed in this paper to get the stripe distribution correlated with vertical micro distortion or micro vibration of objects. The noises in the stripe images of electronic speckle shearography pattern interferometry are comprised of speckle noise and other random noises induced by environmental disturb and instrumental performance, so it's difficult to use familiar filters, such as mean-value filter, medium-value filter and adaptive filter, etc, to remove all noises in the stripe images. The combined filter composed of mean-value filter and wavelet filter is designed to denoise stripe images. The aim of mean-value filter is to remove random noises induced by environmental disturb and instrumental performance, and then the wavelet filter, in which the Meyer wavelet is adopted, is designed to remove speckle noise in the stripe images. The final stripe distribution images after denoising and binarization are listed to prove the denoising validity of combined filter based on wavelet transform.

  6. Multiview Geometry for Texture Mapping 2D Images Onto 3D Range Data Computer Vision and Pattern Recognition, 2006

    E-print Network

    Stamos, Ioannis

    digital photography. A system- atic way for registering 3D range scans and 2D images is thus essentialMultiview Geometry for Texture Mapping 2D Images Onto 3D Range Data Computer Vision and Pattern presents a system that integrates multiview geometry and automated 3D registration techniques for texture

  7. 3D Local Binary Pattern for PET image classification by SVM Application to early Alzheimer disease diagnosis

    E-print Network

    Paris-Sud XI, Université de

    3D Local Binary Pattern for PET image classification by SVM Application to early Alzheimer disease, Feature Extraction, Positron Emission Tomographic images, Alzheimer disease, Machine Learning Abstract: The early diagnostic of Alzheimer disease by non-invasive technique becomes a priority to improve the life

  8. Gaussian pre-filtering for uncertainty minimization in digital image correlation using numerically-designed speckle patterns

    NASA Astrophysics Data System (ADS)

    Mazzoleni, Paolo; Matta, Fabio; Zappa, Emanuele; Sutton, Michael A.; Cigada, Alfredo

    2015-03-01

    This paper discusses the effect of pre-processing image blurring on the uncertainty of two-dimensional digital image correlation (DIC) measurements for the specific case of numerically-designed speckle patterns having particles with well-defined and consistent shape, size and spacing. Such patterns are more suitable for large measurement surfaces on large-scale specimens than traditional spray-painted random patterns without well-defined particles. The methodology consists of numerical simulations where Gaussian digital filters with varying standard deviation are applied to a reference speckle pattern. To simplify the pattern application process for large areas and increase contrast to reduce measurement uncertainty, the speckle shape, mean size and on-center spacing were selected to be representative of numerically-designed patterns that can be applied on large surfaces through different techniques (e.g., spray-painting through stencils). Such 'designer patterns' are characterized by well-defined regions of non-zero frequency content and non-zero peaks, and are fundamentally different from typical spray-painted patterns whose frequency content exhibits near-zero peaks. The effect of blurring filters is examined for constant, linear, quadratic and cubic displacement fields. Maximum strains between ±250 and ±20,000 ?? are simulated, thus covering a relevant range for structural materials subjected to service and ultimate stresses. The robustness of the simulation procedure is verified experimentally using a physical speckle pattern subjected to constant displacements. The stability of the relation between standard deviation of the Gaussian filter and measurement uncertainty is assessed for linear displacement fields at varying image noise levels, subset size, and frequency content of the speckle pattern. It is shown that bias error as well as measurement uncertainty are minimized through Gaussian pre-filtering. This finding does not apply to typical spray-painted patterns without well-defined particles, for which image blurring is only beneficial in reducing bias errors.

  9. IMAGE GUIDED RNA-SEQ REVEALS SUBTYPE-SPECIFIC PATTERNS AT THE INFILTRATIVE MARGINS OF GLIOBLASTOMA

    PubMed Central

    Canoll, Peter; Sims, Peter; Gil, Brian; Pisapia, David; Malone, Hani; Goldstein, Hannah; Lei, Liang; Sonabend, Adam; Yun, Jonathan; Samanamud, Jorge; Sims, Jennifer; Teich, Andrew; Sheth, Sameer; McKhann, Guy; Sisti, Michael; Bruce, Jeffrey

    2014-01-01

    BACKGROUND: The primary treatment of GBM is surgical resection of the contrast enhancing mass, while regions of non-enhancing tumor are left behind, and inevitably gives rise to recurrence. Thus, there is therapeutic significance to understanding the cellular and molecular features of the non-enhancing margins of GBM. Advances in comparative genetic and molecular analyses have uncovered patterns of gene expression and genetic alterations in GBM, and led to the recognition of clinically significant tumor subtypes. However, most previous studies have been based on analysis of tissue that was removed during surgery without documenting the radiographic location. This has precluded the systematic study of intra-tumoral heterogeneity, and its correlation with radiographic regions. We propose a method of sequential image guided biopsies, allowing for specimen localization, intra-tumoral comparative analysis, and the systematic study of infiltrated tissue beyond the borders of contrast enhancement. METHODS: In 77 patients with GBM, multiple stereotactic-guided biopsies were obtained from radiographically distinct regions prior to resection. The radiographic localization of each biopsy was mapped using the 3D intraoperative neuro-navigation system (BrainLab). Sampled regions included areas of contrast enhancement (CE) and adjacent non-enhancing FLAIR+ (NEF+). Samples from each region were divided into pieces processed for RNA-seq and histological analyses. RESULTS: There were significant differences in the cellular density and cellular composition between the CE and NEF+ samples. The CE samples had higher cellularity than NEF+ samples, and were more likely to contain the histological hallmarks of GBM, including vascular proliferation and pseudopalisading necrosis. In contrast, the NEF+ regions showed the histological features of diffusely infiltrating glioma with neoplastic glial cells intermingled with non-neoplastic and reactive cells. RNA-seq showed that the CE and NEF+ regions also had markedly different expression patterns. Comparisons between our image guided biopsies and the TCGA data set showed that the CE regions were enriched for genes associated with the mesenchymal, classical and proneural subtypes while the NEF+ region were enriched for genes of the neural subtype. Further analysis revealed that region-specific and subtype-specific differences in expression patterns were predominantly due to differences in the cellular composition. CONCLUSIONS: Cellular composition is a major determinant of the expression patterns seen at the non-enhancing margins of GBM. The different GBM subtypes show distinct expression patterns that relate the contrast enhancing centers to the non-enhancing margins of the tumors. Understanding these patterns provides a means to infer the molecular and cellular features of glioma tissue left behind after surgery. SECONDARY CATEGORY: Tumor Biology.

  10. Optimized temporally deconvolved Ca²? imaging allows identification of spatiotemporal activity patterns of CA1 hippocampal ensembles.

    PubMed

    Pfeiffer, Thomas; Draguhn, Andreas; Reichinnek, Susanne; Both, Martin

    2014-07-01

    Hippocampal activity is characterized by the coordinated firing of a subset of neurons. Such neuronal ensembles can either be driven by external stimuli to form new memory traces or be reactivated by intrinsic mechanisms to reactivate and consolidate old memories. Hippocampal network oscillations orchestrate this coherent activity. One key question is how the topology, i.e. the functional connectivity of neuronal networks supports their desired function. Recently, this has been addressed by characterizing the intrinsic properties for the highly recurrently connected CA3 region using organotypic slice cultures and Ca(2+) imaging. In the present study, we aimed to determine the properties of CA1 hippocampal ensembles at high temporal and multiple single cell resolution. Thus, we performed Ca(2+) imaging using the chemical fluorescent Ca(2+) indicator Oregon Green BAPTA 1-AM. To achieve most physiological conditions, we used acute hippocampal slices that were recorded in a so-called interface chamber. To faithfully reconstruct firing patterns of multiple neurons in the field of view, we optimized deconvolution-based detection of action potential associated Ca(2+) events. Our approach outperformed currently available detection algorithms by its sensitivity and robustness. In combination with advanced network analysis, we found that acute hippocampal slices contain a median of 11 CA1 neuronal ensembles with a median size of 4 neurons. This apparently low number of neurons is likely due to the confocal imaging acquisition and therefore yields a lower limit. The distribution of ensemble sizes was compatible with a scale-free topology, as far as can be judged from data with small cell numbers. Interestingly, cells were more tightly clustered in large ensembles than in smaller groups. Together, our data show that spatiotemporal activity patterns of hippocampal neuronal ensembles can be reliably detected with deconvolution-based imaging techniques in mouse hippocampal slices. The here presented techniques are fully applicable to similar studies of distributed optical measurements of neuronal activity (in vivo), where signal-to-noise ratio is critical. PMID:24650598

  11. Algorithms for Image Analysis and Combination of Pattern Classifiers with Application to Medical Diagnosis

    NASA Astrophysics Data System (ADS)

    Georgiou, Harris

    2009-10-01

    Medical Informatics and the application of modern signal processing in the assistance of the diagnostic process in medical imaging is one of the more recent and active research areas today. This thesis addresses a variety of issues related to the general problem of medical image analysis, specifically in mammography, and presents a series of algorithms and design approaches for all the intermediate levels of a modern system for computer-aided diagnosis (CAD). The diagnostic problem is analyzed with a systematic approach, first defining the imaging characteristics and features that are relevant to probable pathology in mammo-grams. Next, these features are quantified and fused into new, integrated radio-logical systems that exhibit embedded digital signal processing, in order to improve the final result and minimize the radiological dose for the patient. In a higher level, special algorithms are designed for detecting and encoding these clinically interest-ing imaging features, in order to be used as input to advanced pattern classifiers and machine learning models. Finally, these approaches are extended in multi-classifier models under the scope of Game Theory and optimum collective deci-sion, in order to produce efficient solutions for combining classifiers with minimum computational costs for advanced diagnostic systems. The material covered in this thesis is related to a total of 18 published papers, 6 in scientific journals and 12 in international conferences.

  12. Automatic classification of prostate stromal tissue in histological images using Haralick descriptors and Local Binary Patterns

    NASA Astrophysics Data System (ADS)

    Oliveira, D. L. L.; Nascimento, M. Z.; Neves, L. A.; Batista, V. R.; Godoy, M. F.; Jacomini, R. S.; Duarte, Y. A. S.; Arruda, P. F. F.; Neto, D. S.

    2014-03-01

    In this paper we presente a classification system that uses a combination of texture features from stromal regions: Haralick features and Local Binary Patterns (LBP) in wavelet domain. The system has five steps for classification of the tissues. First, the stromal regions were detected and extracted using segmentation techniques based on thresholding and RGB colour space. Second, the Wavelet decomposition was applied in the extracted regions to obtain the Wavelet coefficients. Third, the Haralick and LBP features were extracted from the coefficients. Fourth, relevant features were selected using the ANOVA statistical method. The classication (fifth step) was performed with Radial Basis Function (RBF) networks. The system was tested in 105 prostate images, which were divided into three groups of 35 images: normal, hyperplastic and cancerous. The system performance was evaluated using the area under the ROC curve and resulted in 0.98 for normal versus cancer, 0.95 for hyperplasia versus cancer and 0.96 for normal versus hyperplasia. Our results suggest that texture features can be used as discriminators for stromal tissues prostate images. Furthermore, the system was effective to classify prostate images, specially the hyperplastic class which is the most difficult type in diagnosis and prognosis.

  13. Constraining mass-diameter relations from hydrometeor images and cloud radar reflectivities in tropical continental and oceanic convective anvils

    NASA Astrophysics Data System (ADS)

    Fontaine, E.; Schwarzenboeck, A.; Delanoë, J.; Wobrock, W.; Leroy, D.; Dupuy, R.; Protat, A.

    2014-01-01

    In this study the density of hydrometeors in tropical clouds is derived from a combined analysis of particle images from 2-D-array probes and associated reflectivities measured with a Doppler cloud radar on the same research aircraft. The mass-diameter m(D) relationship is expressed as a power law with two unknown coefficients (pre-factor, exponent) that need to be constrained from complementary information on hydrometeors, where absolute ice density measurement methods do not apply. Here, at first an extended theoretical study of numerous hydrometeor shapes simulated in 3-D and arbitrarily projected on a 2-D plane allowed to constrain the temporal evolution of the exponent of the mass-diameter relationship with that of the exponent of the surface-diameter relationship that is measured by the 2-D-array probes. The pre-factor is then constrained from theoretical simulations of the radar reflectivities matching the measured reflectivities along the aircraft trajectory. The study has been performed as part of the Megha-Tropiques satellite project, where two types of mesoscale convective systems (MCS) have been investigated: (i) above the African Continent and (ii) above the Indian Ocean. In general, both mass-diameter coefficients (pre-factor and exponent) decrease with decreasing temperature, the decrease is more pronounced for oceanic MCS. The condensed water contents (CWC) calculated from particle size distributions (PSD) and m(D) also decrease with altitude while the concentrations of the hydrometeors increase with altitude. The calculated values of CWC are largest for continental MCS.

  14. Cloud Optical Thickness Effective Particle Radius

    NSDL National Science Digital Library

    Stuart Snodgrass

    2000-04-19

    MODIS provides new capabilities for measuring the properties of clouds. The sensor measures how much of the globe is covered by clouds, identifies various cloud types, and even enables scientists to determine the sizes of the particles that make up clouds. This latter measurement allows scientists to distinguish clouds made of water droplets from those made of ice crystals, and from those made of snow flakes. In this image, the blue clouds are ice clouds, pink indicates snow clouds, and green shows water clouds.

  15. Observing the Invisible through Imaging Mass Spectrometry, a Window into the Metabolic Exchange Patterns of Microbes

    PubMed Central

    Gonzalez, David J.; Xu, Yuquan; Yang, Yu-Liang; Esquenazi, Eduardo; Liu, Wei-Ting; Edlund, Anna; Duong, Tram; Du, Liangcheng; Molnár, István; Gerwick, William H.; Jensen, Paul R.; Fischbach, Michael; Liaw, Chih-Chuang; Straight, Paul; Nizet, Victor; Dorrestein, Pieter C.

    2012-01-01

    Many microbes can be cultured as single-species communities. Often, these colonies are controlled and maintained via the secretion of metabolites. Such metabolites have been an invaluable resource for the discovery of therapeutics (e.g. penicillin, taxol, rapamycin, epothilone). In this article, written for a special issue on imaging mass spectrometry, we show that MALDI-imaging mass spectrometry can be adapted to observe, in a spatial manner, the metabolic exchange patterns of a diverse array of microbes, including thermophilic and mesophilic fungi, cyanobacteria, marine and terrestrial actinobacteria, and pathogenic bacteria. Dependent on media conditions, on average and based on manual analysis, we observed 11.3 molecules associated with each microbial IMS experiment, which was split nearly 50:50 between secreted and colony-associated molecules. The spatial distributions of these metabolic exchange factors are related to the biological and ecological functions of the organisms. This work establishes that MALDI-based IMS can be used as a general tool to study a diverse array of microbes. Furthermore the article forwards the notion of the IMS platform as a window to discover previously unreported molecules by monitoring the metabolic exchange patterns of organisms when grown on agar substrates. PMID:22641157

  16. Imaging the debris cloud around the final flash star IRAS15154-5258

    NASA Astrophysics Data System (ADS)

    Hinkle, Kenneth; Joyce, Richard; Lebzelter, Thomas

    2011-02-01

    A brief yet common evolutionary process is a post-AGB final episode of helium shell burning. This occurs after a low mass star has ejected a planetary nebula and has started on the white dwarf track. Seven stars are now classified with varying degrees of certainty as one of these ``final flash'' objects. Two of these have actually been observed to eject a shell of gas first as a pseudo-photosphere and then as a thick, expanding dust envelope. In 2010B we obtained Gemini NIRI/Altair time to take high spatial resolution images in the K band of the ejecta around five final flash objects. These AO images of the circumstellar shell will be used to measure changes from images recorded a decade or more ago. From these changes we will determine geometric parallaxes and hence luminosities. The luminosity will be compared to stellar evolution models. To complete this project we request time to take a first infrared image of the

  17. USING INDIVIDUAL TREE CROWN APPROACH FOR FOREST VOLUME EXTRACTION WITH AERIAL IMAGES AND LASER POINT CLOUDS

    Microsoft Academic Search

    Juha Hyyppä; Teemu Mielonen; Hannu Hyyppä; Matti Maltamo; Eija Honkavaara; Harri Kaartinen

    2005-01-01

    The objective of this paper is to improve the cost-effectiveness (accuracy of estimates versus applied costs) of present ITC (Individual Tree Crown) approaches which are based on 1) aerial imagery or 2) high density laser scanning data by introducing a hybrid technique (giving the height of each crown with laser data to image derived crown segment) and to compare accuracy

  18. ISCCP Global Cloud Cover

    NSDL National Science Digital Library

    Dave Pape

    1994-03-13

    This animated sequence is a one month sample of composited images from cloud cover data collected from a suite of U.S., European, and Japanese geostationary satellites and U.S. polar orbiting meteorological satellites. This data was composited under the auspices of ISCCP, the International Satellite Cloud Climatology Program.

  19. Uv Imaging of Intermediate-Age Magellanic Cloud Clusters: Hot Stellar Populations in Composite Stellar Systems

    NASA Astrophysics Data System (ADS)

    Freedman, Wendy

    1994-01-01

    Hot stars were first recognized to be an important component of galactic spheroids with early vacuum ultraviolet observations of ellipticals and spiral bulges that were made with OAO. Now, 20 years later, we still do not have a full understanding of the VUV evolution of intermediate and old age stellar populations. Using the WFPC2, we therefore propose to undertake an ultraviolet survey of a sample of star clusters spanning a range in age in the Large Magellanic Cloud. The objective of this investigation is to determine the nature of the hot stellar components in rich, intermediate-to-old age LMC clusters. Ground-based optical/IR studies suggest the presence of short-lived hot horizontal branch and post-asymptotic giant branch stars in these clusters but detailed characterizations of the stars require the ultraviolet capability of HST. In this effort we will be aided by the absence of red leaks in the WFPC2 Woods filter and very high angular resolution of the HST. Although old star clusters in the Galaxy and M31 are, and will be, the subjects of intense investigation by HST, OUR SURVEY WILL BE THE FIRST OF ITS KIND FOR POPULATIONS OF INTERMEDIATE AGE. Such systems are critical for interpreting the spectra and colors of high redshift galaxies, and will provide important support to these studies.

  20. Surface Reflectance Modeling for Martian Cloud Optical Depth Retrievals from CRISM Multispectral Image Cubes

    NASA Astrophysics Data System (ADS)

    Klassen, David R.

    2013-10-01

    In order to retrieve the ice optical depth of martian clouds using a radiative transfer model, one needs to have an independent spectral model of the surface reflectance. Presented here is a comparison of three methods used to model the surface reflectance and the effects on the retrieved ice and dust optical depth. In order to reduce the complexity of the radiative transfer modeling, a fixed set of aerosol optical constants and single aerosol size parameters were used. The retrieval uses DISORT subroutines in an atmosphere modeling program tuned for martian atmospheres to create model reflectance spectra which are then compared to CRISM data. The parameters of total optical depth of ice and dust and surface reflectance are methodically adjusted until the chi-squared between model and data is minimized. This is done over all spatial points to create maps of dust and ice optical depth which are compared to MGS-TES and MO-THEMIS results to assess the effectiveness of the particular surface model. Three types of surface models were tested: a spectrally gray surface, a two-element linear combination of spectral endmembers chosen from the data cube itself, and a two-element linear combination of endmembers recovered from the data cube using principle components analysis and target transformation.

  1. Vector projectile imaging: time-resolved dynamic visualization of complex flow patterns.

    PubMed

    Yiu, Billy Y S; Lai, Simon S M; Yu, Alfred C H

    2014-09-01

    Achieving non-invasive, accurate and time-resolved imaging of vascular flow with spatiotemporal fluctuations is well acknowledged to be an ongoing challenge. In this article, we present a new ultrasound-based framework called vector projectile imaging (VPI) that can dynamically render complex flow patterns over an imaging view at millisecond time resolution. VPI is founded on three principles: (i) high-frame-rate broad-view data acquisition (based on steered plane wave firings); (ii) flow vector estimation derived from multi-angle Doppler analysis (coupled with data regularization and least-squares fitting); (iii) dynamic visualization of color-encoded vector projectiles (with flow speckles displayed as adjunct). Calibration results indicated that by using three transmit angles and three receive angles (-10°, 0°, +10° for both), VPI can consistently compute flow vectors in a multi-vessel phantom with three tubes positioned at different depths (1.5, 4, 6 cm), oriented at different angles (-10°, 0°, +10°) and of different sizes (dilated diameter: 2.2, 4.4 and 6.3 mm; steady flow rate: 2.5 mL/s). The practical merit of VPI was further illustrated through an anthropomorphic flow phantom investigation that considered both healthy and stenosed carotid bifurcation geometries. For the healthy bifurcation with 1.2-Hz carotid flow pulses, VPI was able to render multi-directional and spatiotemporally varying flow patterns (using a nominal frame rate of 416 fps or 2.4-ms time resolution). In the case of stenosed bifurcations (50% eccentric narrowing), VPI enabled dynamic visualization of flow jet and recirculation zones. These findings suggest that VPI holds promise as a new tool for complex flow analysis. PMID:24972498

  2. A New Method to Estimate Cloud Cover Fraction over El Leoncito Observatory from an All-Sky Imager Designed for Upper Atmosphere Studies

    NASA Astrophysics Data System (ADS)

    Martinis, C.; Wilson, J.; Zablowski, P.; Baumgardner, J.; Aballay, J. L.; Garcia, B.; Rastori, P.; Otero, L.

    2013-01-01

    A method for determining cloud cover fraction over El Leoncito Observatory (31.8°S, 69.3°W) is presented. Data from an all-sky imaging system, designed to measure nightglow originating from the mesosphere and thermosphere, is used to determine the fraction of the sky covered by clouds. More than 9,000 hr of observations from May 2006 to December 2010 are used to show that El Leoncito is clear approximately 75--80% of the time. No significant seasonal variations are observed. The optical ground-based data are compared with data from the Moderate Resolution Imaging Spectro-radiometer (MODIS) instrument on board the TERRA and AQUA satellites.

  3. Self-Organization of Spatio-Temporal Hierarchy via Learning of Dynamic Visual Image Patterns on Action Sequences

    PubMed Central

    Jung, Minju; Hwang, Jungsik; Tani, Jun

    2015-01-01

    It is well known that the visual cortex efficiently processes high-dimensional spatial information by using a hierarchical structure. Recently, computational models that were inspired by the spatial hierarchy of the visual cortex have shown remarkable performance in image recognition. Up to now, however, most biological and computational modeling studies have mainly focused on the spatial domain and do not discuss temporal domain processing of the visual cortex. Several studies on the visual cortex and other brain areas associated with motor control support that the brain also uses its hierarchical structure as a processing mechanism for temporal information. Based on the success of previous computational models using spatial hierarchy and temporal hierarchy observed in the brain, the current report introduces a novel neural network model for the recognition of dynamic visual image patterns based solely on the learning of exemplars. This model is characterized by the application of both spatial and temporal constraints on local neural activities, resulting in the self-organization of a spatio-temporal hierarchy necessary for the recognition of complex dynamic visual image patterns. The evaluation with the Weizmann dataset in recognition of a set of prototypical human movement patterns showed that the proposed model is significantly robust in recognizing dynamically occluded visual patterns compared to other baseline models. Furthermore, an evaluation test for the recognition of concatenated sequences of those prototypical movement patterns indicated that the model is endowed with a remarkable capability for the contextual recognition of long-range dynamic visual image patterns. PMID:26147887

  4. Genetic refinement of cloud-masking algorithms for the Multispectral Thermal Imager (MTI)

    Microsoft Academic Search

    S. P. Brumby; K Lewis Hirsch; A. B. Davis; N. R. Harvey; C. A. Rohde

    2001-01-01

    The Multi-spectral Thermal Imager (MTI) is a high-performance remote-sensing satellite designed, owned and operated by the U.S. Department of Energy, with a dual mission in environmental studies and in nonproliferation. It has enhanced spatial and radiometric resolutions and state-of-the-art calibration capabilities. This instrumental development puts a new burden on retrieval algorithm developers to pass this accuracy on to the inferred

  5. Reflections on current and future applications of multiangle imaging to aerosol and cloud remote sensing

    Microsoft Academic Search

    David Diner

    2010-01-01

    The Multi-angle Imaging SpectroRadiometer (MISR) instrument has been collecting global Earth data from NASA's Terra satellite since February 2000. With its 9 along-track view angles, 4 spectral bands, intrinsic spatial resolution of 275 m, and stable radiometric and geometric calibration, no instrument that combines MISR's attributes has previously flown in space, nor is there is a similar capability currently available

  6. IR gas cloud imaging in oil and gas applications: immunity to false stimuli

    NASA Astrophysics Data System (ADS)

    Naranjo, Edward; Baliga, Shakar; Park, John; Bernascolle, Philippe

    2011-05-01

    Fixed gas detection equipment for the petroleum industries is no ordinary equipment. It is designed for continued unattended surveillance in harsh environments. The equipment must be reliable and require limited field maintenance. An additional requirement is a high resistance to false alarms and interferences, which can potentially reduce the detector's efficacy and the level of protection provided. In recent years, several manufactures of IR imaging devices have launched commercial models that are applicable to a wide range of chemical species and suitable for industrial use. These cameras are rugged and sufficiently sensitive to detect low concentrations of combustible and toxic gases. Nonetheless, as users become acquainted with these imaging systems, questions of resilience to solar and flame radiation and other IR sources, interferences by fog or steam, have begun to emerge. These questions, in fact, reflect similar concerns as those raised with open path IR gas detectors when they first appeared in the market over 20 years ago. This paper examines an IR gas imager's performance when exposed to several false alarm sources. Gas detection sensitivity in the presence of false stimuli and response and recovery times under an uncontrolled outdoor environment were measured. The results show the specific model tested is reasonably immune to false alarms, while response times were unaffected by the presence of these sources.

  7. Images of star-forming regions. III. Sources in the NGC 7538 molecular cloud complex

    SciTech Connect

    Campbell, B; Persson, S.E.

    1988-04-01

    Deep optical CCD images of the embedded infrared sources associated with NGC 7538 are presented. A reflected image of IRS 1, the most luminous infrared source in the region, is shown to be positionally offset from the VLA radio source in a direction that is consistent with that of the blueshifted portion of the bipolar molecular outflow toward the north. Maps of the IRS 1 region at 1.65 and 2.2 microns, made with a prototype infrared camera, confirm the positional displacement. The H-K color of IRS 1 is extremely red (greater than 5 mag), which shows that the radio source is indeed totally obscured at wavelengths less than 1.5 micron. This is also consistent with other estimates of the extinction to IRS 1. New VLA radio images of IRS 2 and IRS 3 are also presented. The peculiar object IRS 9, a source that displays deep absorption due to CO molecules in the solid phase, is associated with a diffuse optical nebula that corresponds with the infrared reflection nebula found by Werner et al. (1979). The young stellar objects in NGC 7538 represent a broad evolutionary range in high-mass star formation, from a fully evolved blister-type H II region to much younger objects which have yet to break through their protostellar cocoons. 35 references.

  8. Water Body Extraction from Multi Spectral Image by Spectral Pattern Analysis

    NASA Astrophysics Data System (ADS)

    Nguyen, D. D.

    2012-07-01

    Water is one of the vital components of the Earth environment which needs to be frequently monitored. Satellite multispectral remote sensing image has been used over decades for water body extraction. Methodology of water body extraction can be summarized to three groups: feature extraction, supervised and unsupervised classification and data fusion. These methods, however, are of pure mathematical and statistical approach and little of them explore essential characteristics of multispectral image which is based on ground object radiance absorption behaviour in each sensing spectral bands. The spectral absorption characteristics of water body in visible and infrared bands differ very much from the other ground objects. They depend only on the used spectral bands and can be considered as invariant and sensor independent. In this paper the author proposed an application of spectral pattern analysis for water body extraction using spectral bands green, red, near infrared NIR and short wave infrared SWIR. The proposed algorithm has been used for water body extraction by Spot 5 and Landsat 5 TM images. Ground truth validation was carried out in Hanoi City. The advantage of this algorithm does not base on water body extraction only but it allows to asses also water quality. Different level of turbidity and organic matter contents could be classified by using additional index.

  9. Uncommon primary pelvic retroperitoneal masses in adults: a pattern-based imaging approach.

    PubMed

    Shanbhogue, Alampady K; Fasih, Najla; Macdonald, David B; Sheikh, Adnan M; Menias, Christine O; Prasad, Srinivasa R

    2012-01-01

    There is a broad spectrum of primary pelvic retroperitoneal masses in adults that demonstrate characteristic epidemiologic and histopathologic features and natural histories. These masses may be classified into five distinct subgroups using a pattern-based approach that takes anatomic distribution and certain imaging characteristics into account, allowing greater accuracy in their detection and characterization and helping to optimize patient management. The five groups are cystic (serous and mucinous epithelial neoplasms, pelvic lymphangioma, tailgut cyst, ancient schwannoma), vascular or hypervascular (solitary fibrous tumor, paraganglioma, pelvic arteriovenous malformation, Klippel-Trénaunay-Weber syndrome, extraintestinal GIST [gastrointestinal stromal tumor]), fat-containing (lipoma, liposarcoma, myelolipoma, presacral teratoma), calcified (calcified lymphocele, calcified rejected transplant kidney, rare sarcomas), and myxoid (schwannoma, plexiform neurofibroma, myxoma).Cross-sectional imaging modalities help differentiate the more common gynecologic neoplasms from more unusual masses. In particular, the tissue-specific multiplanar capability of high-resolution magnetic resonance imaging permits better tumor localization and internal characterization, thereby serving as a road map for surgery. PMID:22582360

  10. The detection of weak signal patterns in radar ocean intensity images

    SciTech Connect

    Manasse, R.

    1996-06-15

    Detection of weak patterns in radar ocean RCS images is complicated by the fact that signals and noise are interactive rather than additive and the ambient noise background is non Gaussian or even strongly non Gaussian at low grazing angles. This paper addresses this difficult problem with the aid of two simplifying assumptions: (1) the signal modulation is weak, and (2) departure from Gaussianity is small. In situations where this departure is large, an approach is suggested for reducing this non Gaussianity. The relevant weak signal detection theory, based on the Likelihood ratio, is reviewed and adapted for use in the analysis. The approach to this problem, similar to that previously used for complex images, is facilitated by approximating the multivariate probability distributions as a composite integral involving underlying processes which are assumed to be Gaussian. This formulation, subject to the approximations in the analysis, permits derivation of an ideal detection statistic (which determines the form of optimum receiver) and a signal/noise ratio which characterizes detection performance in the weak signal limit. Implications for image processing are discussed and directions for future analysis are suggested.

  11. WSRT HI imaging of ultra-compact high velocity clouds: gas-bearing dark matter minihalos?

    NASA Astrophysics Data System (ADS)

    Adams, Elizabeth A.; Oosterloo, Tom; Giovanelli, Riccardo; Haynes, Martha P.; Cannon, John M.; Faerman, Yakov; Janesh, William; Janowiecki, Steven; Munoz, Ricardo; Rhode, Katherine L.; Salzer, John Joseph; Sternberg, Amiel

    2015-01-01

    A long standing problem in cosmology is the mismatch between the number of low mass dark matter halos predicted by simulations and the number of low mass galaxies observed in the Local Volume. We recently presented a set of isolated ultra-compact high velocity clouds (UCHVCs) identified within the dataset of the Arecibo Legacy Fast ALFA (ALFALFA) HI line survey that are consistent with representing low-mass gas-bearing dark matter halos within the Local Volume (Adams+ 2013). At distances of ~1 Mpc, the UCHVCs have HI masses of ~10^5 Msun and indicative dynamical masses of 10^7-10^8 Msun. The HI diameters of the UCHVCs range from 4' to 20', or 1 to 6 kpc at a distance of 1 Mpc.We have selected the most compact and isolated UCHVCs with the highest average column densities as representing the best galaxy candidates. These systems have been observed with the Westerbork Synthesis Radio Telescope (WSRT) to enable higher spatial resolution (~60") studies of the HI distribution. The HI morphology revealed by the WSRT data offers clues to the environment and origin of the UCHVCs, the kinematics of the HI allow the underlying mass distribution to be constrained, and the combination of spatial and spectral resolution allow the detection of a cold neutral medium component to the HI. The WSRT HI observations discriminate among the selected galaxy candidates for those objects that are most likely gas-bearing dark matter halos.One UCHVC, AGC198606, is of particular interest as it is located 16 km/s and 1.2 degrees from Leo T and has similar HI properties within the ALFALFA dataset. The WSRT HI observations reveal a smooth HI morphology and a velocity gradient along the HI major axis of the system consistent with rotation. These properties are consistent with the hypothesis that this object is a gas-bearing low-mass dark matter halo.

  12. A Wavelet-based method for multifractal analysis of rough surfaces : Applications to high-resolution satellite images of cloud structure

    Microsoft Academic Search

    A. Arneodo; S. G. Roux; N. Decoster

    2002-01-01

    We apply the 2D wavelet transform modulus maxima (WTMM) method to high-resolution LANDSAT satellite images of cloudy scenes. The computation of the tau(q) and D(h) multifractal spectra of the radiance fields confirms the relevance of the multifractal description to account for the intermittent nature of marine stratocumulus clouds. This analysis reveals that with the available set of experimental data, there

  13. Ground-Truthing Moderate Resolution Satellite Imagery with Near-Surface Canopy Images in Hawai'i's Tropical Cloud Forests

    NASA Astrophysics Data System (ADS)

    Bergstrom, R.; Miura, T.; Lepczyk, C.; Giambelluca, T. W.; Nullet, M. A.; Nagai, S.

    2012-12-01

    Phenological studies are gaining importance globally as the onset of climate change is impacting the timing of green up and senescence in forest canopies and agricultural regions. Many studies use and analyze land surface phenology (LSP) derived from satellite vegetation index time series (VI's) such as those from Moderate Resolution Imaging Spectroradiometer (MODIS) to monitor changes in phenological events. Seasonality is expected in deciduous temperate forests, while tropical regions are predicted to show more static reflectance readings given their stable and steady state. Due to persistent cloud cover and atmospheric interference in tropical regions, satellite VI time series are often subject to uncertainties and thus require near surface vegetation monitoring systems for ground-truthing. This study has been designed to assess the precision of MODIS phenological signatures using above-canopy, down-looking digital cameras installed on flux towers on the Island of Hawai'i. The cameras are part of the expanding Phenological Eyes Network (PEN) which has been implementing a global network of above-canopy, hemispherical digital cameras for forest and agricultural phenological monitoring. Cameras have been installed at two locations in Hawaii - one on a flux tower in close proximity to the Thurston Lave Tube (HVT) in Hawai'i Volcanoes National Park and the other on a weather station in a section of the Hawaiian Tropical Experimental Forest in Laupaphoehoe (LEF). HVT consists primarily of a single canopy species, ohi'a lehua (Metrosideros polymorpha), with an understory of hapu'u ferns (Cibotium spp), while LEF is similarly comprised with an additional dominant species, Koa (Acacia Koa), included in the canopy structure. Given these species' characteristics, HVT is expected to show little seasonality, while LEF has the potential to deviate slightly during periods following dry and wet seasons. MODIS VI time series data are being analyzed and will be compared to images from the cameras which will have VI's extracted from their RGB image planes and will be normalized to be comparable with MODIS VI's. Given Hawai'i's susceptibility to invasion and delicacy of its endemic species, results from this study will provide necessary site specific detail in determining the reliability of satellite based inference in similar tropical phenology studies. Should satellite images provide adequate information, results from this study will allow for extrapolation across similar understudied tropical forests.

  14. Particle aggregation in volcanic clouds from the 2009 eruption of Redoubt Volcano, Alaska: Observations of Doppler weather radar, satellite images and tephra-fall deposits

    NASA Astrophysics Data System (ADS)

    Schneider, D. J.; Wallace, K. L.; Mastin, L. G.

    2012-12-01

    The combined use of weather radar and thermal infrared satellite images provides complementary evidence that can be used to observe and interpret tephra-fall processes. Radar is ideal for characterizing coarse-grained tephra in the eruption column and proximal cloud, while thermal infrared satellite data are better able to characterize the fine-grained distal volcanic cloud. We present observations of radar, satellite images, and character of the tephra-fall deposits from the 2009 eruption of Redoubt Volcano, Alaska. Accretionary tephra-ice pellets (up to 9 mm in diameter) comprised of fine-grained ash (less than 63 micron diameter) were abundant in the many of the proximal tephra-fall deposits. The eruption column and proximal cloud from seventeen explosive events were observed using the MiniMax-250C (MM-250C) volcano-monitoring Doppler weather radar located 80 km from the vent. Radar reflectivity and radial Doppler velocity measurements were made of the column, every 70-90 seconds at a vertical resolution of about 2 km. Radar reflectivity is highly dependent upon particle size and to a lesser extent, concentration. At 80 km distance, the minimum detectable particle diameter for the MM-250C was about 0.2 mm for a mass concentration of 100 g/m3. Thus, the radar was able to observe the aggregate pellets, and not the fine-grained ash. Most of the explosive events were characterized by high radar reflectivity values of 50-60 dBZ in the central core of the eruption column and proximal cloud, which we interpret to be related to the rapid growth of accretionary tephra-ice pellets. Tephra-fall deposits extended for distances of several hundred kilometers and mapped to a minimum mass density of 10 g/m2. However, the MM-250C radar data were only able to observe the dispersed cloud for tens of kilometers from the source, which was well within the 1000 g/m2 isomass contour. Fine-grained ash was prematurely removed from the eruption cloud in proximal locations due to aggregate formation. The relative lack of fine-grained ash may account for the poor thermal infrared brightness temperature signals observed in satellite images for many of the distal volcanic clouds from the 2009 eruption, and possibly from the 1989-90 eruption as well. Time-series of radial Doppler velocity images documented the transition from turbulent mixing in the column to larger scale entrainment within the proximal cloud. Large scale entrainment begins to develop within minutes of eruption onset. Most of the eruption clouds from the explosive events reached the stratosphere, but the large scale entrainment appears to be better developed in the tropospheric portion of the cloud.

  15. Retrieval and Validation of Aerosol Optical Properties over East Asia from TANSO-Cloud and Aerosol Imager

    NASA Astrophysics Data System (ADS)

    Lee, Sanghee; Kim, Jhoon; Kim, Mijin; Choi, Myungje; Go, Sujung; Lim, HyunKwang; Ou, Mi-Lim; Goo, Tae-Young; Yokota, Tatsuya

    2015-04-01

    Aerosol is a significant component on air quality and climate change. In particular, spatial and temporal distribution of aerosol shows large variability over East Asia, thus has large effect in retrieving carbon dioxide from Greenhouse Gases Observing Satellite (GOSAT) Thermal And Near infrared Sensor for carbon Observation Fourier Transform Spectrometer (TANSO-FTS). An aerosol retrieval algorithm was developed from TANSO- Cloud and Aerosol Imager (CAI) onboard the GOSAT. The algorithm retrieves aerosol optical depth (AOD), size distribution of aerosol, and aerosol type in 0.1 degree grid resolution and surface reflectance was estimated using the clear sky composite method. To test aerosol absorptivity, the reflectance difference method was considered using channels of TANSO-CAI. In this study, the retrieved aerosol optical depth (AOD) was compared with those of Aerosol Robotic NETwork (AERONET) and MODerate resolution Imaging Sensor (MODIS) dataset from September 2011 and August 2014. Comparisons of AODs between AERONET and CAI show the reasonably good correlation with correlation coefficient of 0.77 and regression slope of 0.87 for the whole period. Moreover, those between MODIS and CAI for the same period show correlations with correlation coefficient of 0.7 ~ 0.9 and regression slope of 0.7 ~ 1.2, depending on season and comparison regions however, the largest error source in aerosol retrieval has been surface reflectance. Over ocean and some Land, surface reflectance tends to be overestimated, and thereby CAI-AOD tends to be underestimated. Based on the results with CAI algorithm developed, the algorithm is continuously improved for better performance.

  16. Automated cloud and shadow detection and filling using two-date Landsat imagery in the United States

    USGS Publications Warehouse

    Jin, Suming; Homer, Collin G.; Yang, Limin; Xian, George; Fry, Joyce; Danielson, Patrick; Townsend, Philip A.

    2013-01-01

    A simple, efficient, and practical approach for detecting cloud and shadow areas in satellite imagery and restoring them with clean pixel values has been developed. Cloud and shadow areas are detected using spectral information from the blue, shortwave infrared, and thermal infrared bands of Landsat Thematic Mapper or Enhanced Thematic Mapper Plus imagery from two dates (a target image and a reference image). These detected cloud and shadow areas are further refined using an integration process and a false shadow removal process according to the geometric relationship between cloud and shadow. Cloud and shadow filling is based on the concept of the Spectral Similarity Group (SSG), which uses the reference image to find similar alternative pixels in the target image to serve as replacement values for restored areas. Pixels are considered to belong to one SSG if the pixel values from Landsat bands 3, 4, and 5 in the reference image are within the same spectral ranges. This new approach was applied to five Landsat path/rows across different landscapes and seasons with various types of cloud patterns. Results show that almost all of the clouds were captured with minimal commission errors, and shadows were detected reasonably well. Among five test scenes, the lowest producer's accuracy of cloud detection was 93.9% and the lowest user's accuracy was 89%. The overall cloud and shadow detection accuracy ranged from 83.6% to 99.3%. The pixel-filling approach resulted in a new cloud-free image that appears seamless and spatially continuous despite differences in phenology between the target and reference images. Our methods offer a straightforward and robust approach for preparing images for the new 2011 National Land Cover Database production.

  17. Millimeter-wave imaging radiometer for cloud, precipitation and atmospheric water vapor studies

    NASA Technical Reports Server (NTRS)

    Racette, P. E.; Dod, L. R.; Shiue, J. C.; Adler, R. F.; Jackson, D. M.; Gasiewski, A. J.; Zacharias, D. S.

    1992-01-01

    A millimeter-wave imaging radiometer (MIR) developed by NASA Goddard Space Flight Center is described. The MIR is a nine-channel total power radiometer developed for atmospheric research. Three dual-pass band channels are centered about the strongly opaque 183-GHz water vapor absorption line; the frequencies are 183 +/- 1, +/- 3, and +/- 7 GHz. Another channel is located on the wing of this band at 150 GHz. These four channels have varying degrees of opacity from which the water vapor profile can be inferred. The design and salient characteristics of this instrument are discussed, together with its expected benefits.

  18. An excess of emission in the dark cloud LDN 1111 with the Arcminute Microkelvin Imager

    E-print Network

    AMI Consortium; :; A. M. M. Scaife; N. Hurley-Walker; D. A. Green; M. L. Davies; K. J. B. Grainge; M. P. Hobson; A. N. Lasenby; M. Lopez-Caniego; G. G. Pooley; R. D. E. Saunders; P. F. Scott; D. J. Titterington; E. M. Waldram; J. T. L. Zwart

    2008-12-04

    We present observations of the Lynds' dark nebula LDN 1111 made at microwave frequencies between 14.6 and 17.2 GHz with the Arcminute Microkelvin Imager (AMI). We find emission in this frequency band in excess of a thermal free--free spectrum extrapolated from data at 1.4 GHz with matched uv-coverage. This excess is > 15 sigma above the predicted emission. We fit the measured spectrum using the spinning dust model of Drain & Lazarian (1998a) and find the best fitting model parameters agree well with those derived from Scuba data for this object by Visser et al. (2001).

  19. Parkinson's disease-related perfusion and glucose metabolic brain patterns identified with PCASL-MRI and FDG-PET imaging

    PubMed Central

    Teune, Laura K.; Renken, Remco J.; de Jong, Bauke M.; Willemsen, Antoon T.; van Osch, Matthias J.; Roerdink, Jos B.T.M.; Dierckx, Rudi A.; Leenders, Klaus L.

    2014-01-01

    Introduction Under normal conditions, the spatial distribution of resting cerebral blood flow and cerebral metabolic rate of glucose are closely related. A relatively new magnetic resonance (MR) technique, pseudo-continuous arterial spin labeling (PCASL), can be used to measure regional brain perfusion. We identified a Parkinson's disease (PD)-related perfusion and metabolic covariance pattern in the same patients using PCASL and FDG-PET imaging and assessed (dis)similarities in the disease-related pattern between perfusion and metabolism in PD patients. Methods Nineteen PD patients and seventeen healthy controls underwent [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging. Of 14 PD patients and all healthy controls PCASL-MRI could be obtained. Data were analyzed using scaled subprofile model/principal component analysis (SSM/PCA). Results Unique Parkinson's disease-related perfusion and metabolic covariance patterns were identified using PCASL and FDG-PET in the same patients. The PD-related metabolic covariance brain pattern is in high accordance with previously reports. Also our disease-related perfusion pattern is comparable to the earlier described perfusion pattern. The most marked difference between our perfusion and metabolic patterns is the larger perfusion decrease in cortical regions including the insula. Conclusion We identified PD-related perfusion and metabolic brain patterns using PCASL and FDG-PET in the same patients which were comparable with results of existing research. In this respect, PCASL appears to be a promising addition in the early diagnosis of individual parkinsonian patients. PMID:25068113

  20. ZebraFISH: fluorescent in situ hybridization protocol and three-dimensional imaging of gene expression patterns.

    PubMed

    Welten, Monique C M; de Haan, Simon B; van den Boogert, Niels; Noordermeer, Jasprien N; Lamers, Gerda E M; Spaink, Herman P; Meijer, Annemarie H; Verbeek, Fons J

    2006-01-01

    We present a method and protocol for fluorescent in situ hybridization (FISH) in zebrafish embryos to enable three-dimensional imaging of patterns of gene expression using confocal laser scanning microscopy. We describe the development of our protocol and the processing workflow of the three-dimensional images from the confocal microscope. We refer to this protocol as zebraFISH. FISH is based on the use of tyramide signal amplification (TSA), which results in highly sensitive and very localized fluorescent staining. The zebraFISH protocol was extensively tested and here we present a panel of five probes for genes expressed in different tissues or single cells. FISH in combination with confocal laser scanning microscopy provides an excellent tool to generate three-dimensional images of patterns of gene expression. We propose that such three-dimensional images are suitable for building a repository of gene expression patterns, complementary to our previously published three-dimensional anatomical atlas of zebrafish development (bio-imaging.liacs.nl/). Our methodology for image processing of three-dimensional confocal images allows an analytical approach to the definition of gene expression domains based on the three-dimensional anatomical atlas. PMID:18377226

  1. Introduction to Clouds

    NSDL National Science Digital Library

    This site gives students an opportunity to explore storm clouds and climate change through the use of National Aeronautic and Space Administration (NASA) climate research data obtained through satellite imaging. The challenge is to investigate actual scientific research data on clouds and storms, and make the resulting observations and interpretations available to NASA research scientists for review. The interactive site will allow students to discover what the major types of clouds produced by storms are and whether these clouds help to cool or warm the Earth's surface. Storms are the major producers of clouds in the Earth's atmosphere, so students investigate the relationship between the types of clouds in order to make their conclusions.

  2. Applying Chemical Imaging Analysis to Improve Our Understanding of Cold Cloud Formation

    NASA Astrophysics Data System (ADS)

    Laskin, A.; Knopf, D. A.; Wang, B.; Alpert, P. A.; Roedel, T.; Gilles, M. K.; Moffet, R.; Tivanski, A.

    2012-12-01

    The impact that atmospheric ice nucleation has on the global radiation budget is one of the least understood problems in atmospheric sciences. This is in part due to the incomplete understanding of various ice nucleation pathways that lead to ice crystal formation from pre-existing aerosol particles. Studies investigating the ice nucleation propensity of laboratory generated particles indicate that individual particle types are highly selective in their ice nucleating efficiency. This description of heterogeneous ice nucleation would present a challenge when applying to the atmosphere which contains a complex mixture of particles. Here, we employ a combination of micro-spectroscopic and optical single particle analytical methods to relate particle physical and chemical properties with observed water uptake and ice nucleation. Field-collected particles from urban environments impacted by anthropogenic and marine emissions and aging processes are investigated. Single particle characterization is provided by computer controlled scanning electron microscopy with energy dispersive analysis of X-rays (CCSEM/EDX) and scanning transmission X-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). A particle-on-substrate approach coupled to a vapor controlled cooling-stage and a microscope system is applied to determine the onsets of water uptake and ice nucleation including immersion freezing and deposition ice nucleation as a function of temperature (T) as low as 200 K and relative humidity (RH) up to water saturation. We observe for urban aerosol particles that for T > 230 K the oxidation level affects initial water uptake and that subsequent immersion freezing depends on particle mixing state, e.g. by the presence of insoluble particles. For T < 230 K the particles initiate deposition ice nucleation well below the homogeneous freezing limit. Particles collected throughout one day for similar meteorological conditions show very similar deposition ice nucleation efficiencies, indicating that chemical changes due to aging processes might not have a dominant effect on this nucleation pathway consistent with previous observations. The field-collected particles exhibit ice nucleation efficiencies that suggest that these kinds of particles can play a potential role in mixed-phase and cirrus cloud formation. Initial results applying single particle IN analysis using CCSEM/EDX and STXM/NEXAFS reveal that a significant amount of IN are coated by organics and, thus, are similar to the majority of the particles that do not nucleate ice. However respective particle cores can be of different mineral composition. This suggests that highly abundant and chemically complex aerosol, typical of an urban environment, initiate ice despite possessing potentially mediocre ice nucleation efficiency. This is in contrast to the general notion that the most efficient IN and usually less abundant particles of a population will govern ice nucleation in an air parcel.

  3. Connectivity constraint-based sequential pattern extraction from Satellite Image Time Series (SITS)

    NASA Astrophysics Data System (ADS)

    Julea, Andreea; Méger, Nicolas

    2013-10-01

    The temporal evolution of pixel values in Satellite Image Time Series (SITS) is considered as criterion for the characterization, discrimination and identification of terrestrial objects and phenomena. Due to the exponential behavior of sequences number with specialization, Sequential Data Mining (SDM) techniques need to be applied. The huge search and solution spaces imply the use of constraints according to the user's knowledge, interest and expectation. The spatial aspect of the data was taken into account by the introduction of connectivity measures that characterize the pixels tendency to form objects. These measures can highlight stratifications in data structure, can be useful for shape recognition and offer a base for post-processing operations similar to those from mathematical morphology (dilation, erosion etc.). The conjunction of corresponding Connectivity Constraints (CC) with the Support Constraint (SC) leads to the extraction of Grouped Frequent Sequential Patterns (GFSP), a concept with proved capability for preliminary description and localization of terrestrial events. This work is focused on efficient SITS extraction of evolutions that fulfill SC and CC. Different types of extractions using anti-monotone constraints are analyzed. Experiments performed on two interferometric SITS are used to illustrate the potential of the approach to find interesting evolution patterns.

  4. The statistical analysis of multi-voxel patterns in functional imaging.

    PubMed

    Schreiber, Kai; Krekelberg, Bart

    2013-01-01

    The goal of multi-voxel pattern analysis (MVPA) in BOLD imaging is to determine whether patterns of activation across multiple voxels change with experimental conditions. MVPA is a powerful technique, its use is rapidly growing, but it poses serious statistical challenges. For instance, it is well-known that the slow nature of the BOLD response can lead to greatly exaggerated performance estimates. Methods are available to avoid this overestimation, and we present those here in tutorial fashion. We go on to show that, even with these methods, standard tests of significance such as Students' T and the binomial tests are invalid in typical MRI experiments. Only a carefully constructed permutation test correctly assesses statistical significance. Furthermore, our simulations show that performance estimates increase with both temporal as well as spatial signal correlations among multiple voxels. This dependence implies that a comparison of MVPA performance between areas, between subjects, or even between BOLD signals that have been preprocessed in different ways needs great care. PMID:23861966

  5. Cirrus cloud top temperatures retrieved from radiances in the National Polar-Orbiting Operational Environmental Satellite System--Visible Infrared Imager Radiometer Suite 8.55 and 12.0 ?m bandpasses

    NASA Astrophysics Data System (ADS)

    Wong, Eric; Hutchison, Keith D.; Ou, S. C.; Liou, K. N.

    2007-03-01

    We describe what is believed to be a new approach developed for the National Polar-Orbiting Operational Environmental Satellite System (NPOESS) to retrieve pixel-level, cirrus cloud top temperatures (CTTs) from radiances observed in the 8.55 and 12.0 ?m bandpasses. The methodology solves numerically a set of nonlinear algebraic equations derived from the theory of radiative transfer based upon the correlation between emissivities in these two bandpasses. This new approach has been demonstrated using NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) as a proxy to Visible Infrared Imager Radiometer Suite (VIIRS) data. Many scenes have been analyzed covering a wide range of geophysical conditions, including single-layered and multilayered cirrus cloud situations along with diverse backgrounds and seasons. For single-layer clouds, the new approach compares very favorably with the MODIS 5 km resolution cloud products; the mean CTT for both methods are very close, while the standard deviation for the new approach is smaller. However, in multilayered cloud situations, the mean CTTs for the new approach appear to be colder than the CTTs from MODIS cloud products, which are acknowledged to be too warm. Finally, partly because the new approach is applied at the pixel level, CTTs do not increase toward cloud edges as is seen in the MODIS products. Based upon these initial results, the new approach to retrieve improved VIIRS cloud top properties has been incorporated into the ground-based data processing segment of the NPOESS system where prelaunch testing of all VIIRS algorithms continues.

  6. A Mid-Infrared Imaging Survey of Embedded Young Stellar Objects in the (rho) Ophiuchi Cloud Core

    NASA Technical Reports Server (NTRS)

    Barsony, Mary; Ressler, Michael E.; Marsh, Kenneth A.

    2005-01-01

    Results of a comprehensive, new, ground-based mid-infrared imaging survey of the young stellar population of the (rho) Ophiuchi cloud are presented. Data were acquired at the Palomar 5m and at the Keck 10m telescopes with the MIRLIN and LWS instruments, at 0'.5 and 0'.25 resolutions, respectively. Of 172 survey objects, 85 were detected. Among the 22 multiple systems observed, 15 were resolved and their individual component fluxes determined. A plot of the frequency distribution of the detected objects with SED spectral slope shows that YSOs spend approx.4 x 10(exp 5) yr in the flat-spectrum phase, clearing out their remnant infall envelopes. Mid-infrared variability is found among a significant fraction of the surveyed objects and is found to occur for all SED classes with optically thick disks. Large-amplitude near-infrared variability, also found for all SED classes with optically thick disks, seems to occur with somewhat higher frequency at the earlier evolutionary stages. Although a general trend of mid-infrared excess and near-infrared veiling exists progressing through SED classes, with Class I objects generally exhibiting r(sub K) >= 1, flat-spectrum objects with r(sub K) >= 0.58, and Class III objects with r(sub K) =0, Class II objects exhibit the widest range of r(sub K) values, ranging from 0 <= r(sub K) <= 4.5. However, the highly variable value of veiling that a single source can exhibit in any of the SED classes in which active disk accretion can take place is striking and is direct observational evidence for highly time-variable accretion activity in disks. Finally, by comparing mid-infrared versus near-infrared excesses in a subsample with well-determined effective temperatures and extinction values, disk-clearing mechanisms are explored. The results are consistent with disk clearing proceeding from the inside out.

  7. Magnetic imaging of ion-irradiation patterned CoPt multilayers using complementary electron and photon probes

    E-print Network

    Krishnan, Kannan M.

    Magnetic imaging of ion-irradiation patterned CoÕPt multilayers using complementary electron-plane component and magnetic transmission x-ray microscopy perpendicular magnetization . The Co/Pt films transmission x-ray microscopy M-TXM 10 measuring perpendicular magnetization.11 The Co/Pt multilayers, 20 nm Pt

  8. CHARACTERIZATION OF STOCHASTIC PROPERTIES OF EMBEDDED MESSAGE AND THE LSB PATTERN IN COLOUR AND GRAY-SCALE IMAGES

    Microsoft Academic Search

    C. Saha; N. Maji; A. Gupta; D. Mazumdar; A. B. Saha

    LSB steganography is one of the popular ways of message embedding in different multimedia cover objects. A number of commercial steganography software tools use LSB insertion as a method of message packing. In the present work the detailed study has been made regarding the stochastic properties of the embedded message and LSB pattern in colour and gray scale images. The

  9. Measurement of surface currents using sequential synthetic aperture radar images of slick patterns near the edge of the Gulf Stream

    Microsoft Academic Search

    David R. Lyzenga; George O. Marmorino

    1998-01-01

    Two-dimensional surface currents are estimated over an area of 00100 kmnear the inshore edge of the Gulf Stream by correlating the surface slick patterns observed on two synthetic aperture radar (SAR) images collected about 20 min apart. The currents obtained from this analysis are found to agree well with shipboard acoustic Doppler current profiler (ADCP) measurements at 10 to 20-m

  10. Cloud top structure of a tornadic thunderstorm from 3 min interval stereo satellite images compared with radar and other observations

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Adler, R. F.

    1980-01-01

    Cloud heights from 3 min interval GOES EAST/GOES WEST stereo pairs are shown to provide an important new tool for studying severe convective storms with potential for the detection of severe local storms. It is possible to use these data for observing cloud top structure as a function of time on a size scale of few kilometers with quantitative height measurements with relative and absolute accuracies on the order of + or - 0.5 km. It is noted that stereo height measurements detect cirrus anvil cloud decks at two altitudes corresponding to a lower stable layer and the main tropopause.

  11. MY NASA DATA Lesson Plan: Storm Clouds-Fly over a Late Winter Storm onboard a NASA Earth Observing Satellite

    NSDL National Science Digital Library

    2006-01-01

    : This lesson plan uses Clouds and Earth's Radiant Energy System (CERES) cloud data and a weather map to explore cloud coverage during a winter storm. When atmospheric scientists, including meteorologists, study weather patterns, they may use several different sources of information. For example, in studying storm patterns, they may use a combination of Earth Observing Satellite data, such as from CERES, or NOAA weather satellite imagery, and geographical tools to determine locations and paths of storms. As one part of the training to analyze this data and imagery, scientists look at 'case studies' such as the late winter storm shown in the weather satellite imagery included with the lesson. An infrared satellite image looks at the temperature. Cold things (like high clouds) are very bright. Warm things (like Mexico and Florida) are dark. The imagery can be compared to data collected by other satellites, so that improved models of storm patterns can be developed.

  12. Guiding an image acquisition strategy: MODIS-derived growing season timing and cloud cover probability as inputs to a global agriculture monitoring (GEO-GLAM) system of systems

    NASA Astrophysics Data System (ADS)

    Whitcraft, A. K.; Vermote, E.

    2012-12-01

    Satellite remote sensing is an invaluable tool in the collection of data and generation of information about global agricultural production and food security. In order to secure the necessary image acquisitions for these global agricultural monitoring applications, we must first articulate Earth observation (EO) requirements for the diverse agricultural landscapes and cropping systems which cover the land surface. Crucial to this task are the identification of growing season timing at a meaningful spatial scale, so as to better define the necessary periods of image acquisition, as well as the determination of the likelihood of a cloud-free observation during different portions of the agricultural growing season. To this end, ten years of MODIS imagery have been used to determine phenological transition dates (start, peak, and end of season) and their ranges over that time period at 0.5 degree globally. This is the first set of global, satellite-derived, cropland-specific calendar dates. Because cloud cover presents a temporally and spatially heterogeneous obstacle in optical remote sensing of many important agricultural areas, roughly a decade of MODIS observations have been used to determine the likelihood of a cloud-free observation during different portions of the agricultural growing season at 0.05 degree. This research shows persistent cloud cover during crucial portions of the growing season for some important agricultural regions, information which can be used to better define the actual repeat time required to obtain a valid acquisition and provides evidence for a constellation approach for Earth observations for agricultural monitoring. Coupled with the growing season calendars, this research provides important inputs to agricultural production and food security monitoring in the context of the Global Agricultural Monitoring initiative (GEO-GLAM), an effort by the Group on Earth Observations (GEO) to synergize existing national and regional observation systems for improved agricultural production and food security monitoring.

  13. Keyhole reflection-mode coherent diffraction imaging of nano-patterned surfaces using a tabletop EUV source

    NASA Astrophysics Data System (ADS)

    Shanblatt, Elisabeth; Seaberg, Matthew; Zhang, Bosheng; Gardner, Dennis; Murnane, Margaret; Kapyetn, Henry; Adams, Daniel

    2014-03-01

    We demonstrate the first reflection-mode keyhole coherent diffraction imaging (CDI) of non-isolated samples from a single diffraction pattern. A tabletop high harmonic generation (HHG) beam at 30 nm with a curved wave-front is used to illuminate Ti nano-patterns on a Si substrate at 45 degree angle of incidence. The 30 nm illumination beam profile is first characterized using ptychograhic CDI. Keyhole CDI is then used to image the nano-sample. In contrast to ptychography CDI, keyhole CDI needs only one diffraction pattern, and therefore requires no scanning of the sample. This is a significant advantage for ultrafast pump-probe imaging of thermal or spin transport, allowing a sequence of time-delayed images of the same region to be easily acquired. Our technique opens the door for imaging dynamics in nanostructures with sub-10 nm spatial resolution and fs temporal resolution. National Science Foundation Engineering Research Center in EUV Science and Technology, AMRDEC, DARPA PULSE, SRC grant 2013-OJ-2443, NSSEFF Fellowship, NSF IGERT program.

  14. SU-D-BRD-02: A Web-Based Image Processing and Plan Evaluation Platform (WIPPEP) for Future Cloud-Based Radiotherapy

    SciTech Connect

    Chai, X; Liu, L; Xing, L [Stanford UniversitySchool of Medicine, Stanford, CA (United States)

    2014-06-01

    Purpose: Visualization and processing of medical images and radiation treatment plan evaluation have traditionally been constrained to local workstations with limited computation power and ability of data sharing and software update. We present a web-based image processing and planning evaluation platform (WIPPEP) for radiotherapy applications with high efficiency, ubiquitous web access, and real-time data sharing. Methods: This software platform consists of three parts: web server, image server and computation server. Each independent server communicates with each other through HTTP requests. The web server is the key component that provides visualizations and user interface through front-end web browsers and relay information to the backend to process user requests. The image server serves as a PACS system. The computation server performs the actual image processing and dose calculation. The web server backend is developed using Java Servlets and the frontend is developed using HTML5, Javascript, and jQuery. The image server is based on open source DCME4CHEE PACS system. The computation server can be written in any programming language as long as it can send/receive HTTP requests. Our computation server was implemented in Delphi, Python and PHP, which can process data directly or via a C++ program DLL. Results: This software platform is running on a 32-core CPU server virtually hosting the web server, image server, and computation servers separately. Users can visit our internal website with Chrome browser, select a specific patient, visualize image and RT structures belonging to this patient and perform image segmentation running Delphi computation server and Monte Carlo dose calculation on Python or PHP computation server. Conclusion: We have developed a webbased image processing and plan evaluation platform prototype for radiotherapy. This system has clearly demonstrated the feasibility of performing image processing and plan evaluation platform through a web browser and exhibited potential for future cloud based radiotherapy.

  15. Analytical estimation of emission zone mean position and width in organic light-emitting diodes from emission pattern image-source interference fringes

    E-print Network

    Tessler, Nir

    from emission pattern image-source interference fringes Ariel Epstein, Matthew Roberts, Nir Tessler-voltage polariton electroluminescence from an ultrastrongly coupled organic light-emitting diode Appl. Phys. Lett in organic light-emitting diodes from emission pattern image-source interference fringes Ariel Epstein,1,a

  16. 18F-fluorothymidine-pet imaging of glioblastoma multiforme: effects of radiation therapy on radiotracer uptake and molecular biomarker patterns.

    PubMed

    Chandrasekaran, Sanjay; Hollander, Andrew; Xu, Xiangsheng; Benci, Joseph L; Davis, James J; Dorsey, Jay F; Kao, Gary

    2013-01-01

    Introduction. PET imaging is a useful clinical tool for studying tumor progression and treatment effects. Conventional (18)F-FDG-PET imaging is of limited usefulness for imaging Glioblastoma Multiforme (GBM) due to high levels of glucose uptake by normal brain and the resultant signal-to-noise intensity. (18)F-Fluorothymidine (FLT) in contrast has shown promise for imaging GBM, as thymidine is taken up preferentially by proliferating cells. These studies were undertaken to investigate the effectiveness of (18)F-FLT-PET in a GBM mouse model, especially after radiation therapy (RT), and its correlation with useful biomarkers, including proliferation and DNA damage. Methods. Nude/athymic mice with human GBM orthografts were assessed by microPET imaging with (18)F-FDG and (18)F-FLT. Patterns of tumor PET imaging were then compared to immunohistochemistry and immunofluorescence for markers of proliferation (Ki-67), DNA damage and repair (?H2AX), hypoxia (HIF-1?), and angiogenesis (VEGF). Results. We confirmed that (18)F-FLT-PET uptake is limited in healthy mice but enhanced in the intracranial tumors. Our data further demonstrate that (18)F-FLT-PET imaging usefully reflects the inhibition of tumor by RT and correlates with changes in biomarker expression. Conclusions. (18)F-FLT-PET imaging is a promising tumor imaging modality for GBM, including assessing RT effects and biologically relevant biomarkers. PMID:23690748

  17. Imaging Spatial and Temporal Patterns of Landslide Movement with Ground-Based Radar Interferometry

    NASA Astrophysics Data System (ADS)

    Gomez, F.; Held, B. M.; Lowry, B. W.; Mooney, M.; Zhou, W.; Grasmick, J.

    2012-12-01

    Ground-based interferometric radar (GBIR) provides a means of addressing questions about landslides that involve monitoring changes across large areas (<10 km2) with high spatial (<1 mm) and temporal precision (<1 hr). Recent studies have shown that landslide displacement rates may exhibit sensitivity to unlikely sources, such as atmospheric tides. This study applies GBIR to measure temporal and spatial patterns of movement in a slow-velocity slide on the west side of the Colorado Front Range. Multiple deployments of the GBIR permit assessing long-term (seasonal) variations in slide kinematics, which compared favorably with ground-truth measurements using more conventional surveying techniques. Each GBIR deployment involves long observation sessions (5 - 36 hours) with images acquired every 7.5 - 15 minutes. The data redundancy permits rigorous time-series analysis that results in 0.3 - 0.4 mm positional uncertainties. The time series is further constrained by imposing a 'no back-slip' condition that is justified by the nearly horizontal viewing geometry facing in the slide's direction of transport. The slide demonstrates significant seasonal variations that correspond with variations in groundwater measured by piezometric wells in the study area. These are primarily driven by variations in spring snow melt and precipitation. Additionally, short-span time series for individual observation sessions suggest short term variations in displacement rate over periods of several hours. One possible model for this quasi stick-slip behavior may involve release of excess fluid pressure during slide movement that increases frictional coupling at the base of the slide. As a tool for geodetic imaging, offers a significant improvement in temporal and spatial resolution compared with satellite and airborne radar interferometry. The sensitivity and temporal sampling of GBIR complement well the spatial resolution and 3-dimensional displacements measured with other methods, such as terrestrial laser scanners.

  18. Magnetic resonance imaging of retropharyngeal lymph node metastasis in nasopharyngeal carcinoma: Patterns of spread

    SciTech Connect

    Liu Lizhi [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in Southern China, Cancer Center, Sun Yat-sen University, Guangzhou (China); Zhang Guoyi [Department of Radiation Oncology, State Key Laboratory of Oncology in Southern China, Cancer Center, Sun Yat-sen University, Guangzhou (China); Xie Chuangmiao [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in Southern China, Cancer Center, Sun Yat-sen University, Guangzhou (China); Liu Xuewen [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in Southern China, Cancer Center, Sun Yat-sen University, Guangzhou (China); Cui Chunyan [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in Southern China, Cancer Center, Sun Yat-sen University, Guangzhou (China); Li Li [Imaging Diagnosis and Interventional Center, State Key Laboratory of Oncology in Southern China, Cancer Center, Sun Yat-sen University, Guangzhou (China)]. E-mail: lililixj@hotmail.com

    2006-11-01

    Purpose: To investigate the incidence, distribution, and spread pattern of retropharyngeal lymph node (RLN) involvement in patients with nasopharyngeal carcinoma (NPC) by using magnetic resonance imaging (MRI). Methods and Materials: The MR images of 275 patients with newly diagnosed NPC were reviewed retrospectively. Nodes were classified as metastatic based on size criteria, the presence of nodal necrosis, and extracapsular spread. Results: Retropharyngeal lymph node involvement was detected in 175 (63.6%) patients. Metastatic RLNs were seen at the following levels: occipital bone, 24 (9.6%) nodes; C1, 157 (62.5%) nodes; C1/2, 40 (15.9%) nodes; C2, 27 (10.8%) nodes; C2/3, 1 (0.4%) node; and C3, 2 (0.8%) nodes. The incidence of RLN involvement was equal to the incidence of cervical lymph node involvement (81.4% vs. 81.4%) in 215 patients with nodal metastases. A significantly higher incidence of metastatic RLNs was observed in the presence of oropharynx, prestyloid parapharyngeal space, post-styloid parapharyngeal space, longus colli muscle, medial pterygoid muscle, levator muscle of velum palatini, tensor muscle of velum palatini, Level II node, Level III node, and Level V node involvement. A significantly lower incidence of metastatic RLNs was found in T1, N0, and Stage I disease. Conversely, no significant difference in the incidence of metastatic RLNs was observed between T1, 2, and, 3; N2 and N3; or Stage II, III, and IV disease. Conclusions: There is an orderly decrease in the incidence of metastatic lateral RLNs from the C1 to C3 level. Metastatic RLNs associate well with involvement of certain structures in early stage primary tumors and lymph node metastases of the upper jugular chain (Level II, Level III nodes) and the posterior triangle (Level V nodes). Both RLNs and cervical Level II nodes appear to be the first-echelon nodes in NPC.

  19. Magnetic imaging of ion-irradiation patterned Co/Pt multilayers using complementary electron and photon probes

    SciTech Connect

    Kusinski, G.J.; Krishnan, K.M.; Denbeaux, G.; Thomas, G.; Terris, B.D.; Weller, D.

    2001-04-01

    The three-dimensional magnetic structure and reversal mechanism of patterned Co/Pt multilayers, were imaged using complementary Lorentz transmission electron microscopy (LTEM) (in-plane component) and magnetic transmission x-ray microscopy (M-TXM) (perpendicular magnetization). The Co/Pt films with perpendicular anisotropy were patterned by ion irradiation through a stencil mask to produce in-plane magnetization in the irradiated regions. The boundaries of the patterns, defined by the transition from out-of-plane to in-plane magnetization, were found to be determined by the stencil mask, whilst the scale of the magnetic reversal by the physical microstructure. The nucleation fields were substantially reduced to 50 Oe for the in-plane regions and 1 kOe for the perpendicular regions, comparing to 4.5 kOe for the as-grown film. The perpendicular reversals were found to always originate at the pattern boundaries.

  20. Influence of image resolution and thresholding on the apparent mass fractal characteristics of preferential flow patterns

    E-print Network

    Walter, M.Todd

    Influence of image resolution and thresholding on the apparent mass fractal characteristics choices regarding image resolution, the definition adopted for the "fractal" dimension statistical significance, with R 0.999. Of the various parameters subject to choice, image resolution seems

  1. Molecular imaging coupled to pattern recognition distinguishes response to temozolomide in preclinical glioblastoma.

    PubMed

    Delgado-Goñi, Teresa; Julià-Sapé, Margarida; Candiota, Ana Paula; Pumarola, Martí; Arús, Carles

    2014-11-01

    Non-invasive monitoring of response to treatment of glioblastoma (GB) is nowadays carried out using MRI. MRS and MR spectroscopic imaging (MRSI) constitute promising tools for this undertaking. A temozolomide (TMZ) protocol was optimized for GL261 GB. Sixty-three mice were studied by MRI/MRS/MRSI. The spectroscopic information was used for the classification of control brain and untreated and responding GB, and validated against post-mortem immunostainings in selected animals. A classification system was developed, based on the MRSI-sampled metabolome of normal brain parenchyma, untreated and responding GB, with a 93% accuracy. Classification of an independent test set yielded a balanced error rate of 6% or less. Classifications correlated well both with tumor volume changes detected by MRI after two TMZ cycles and with the histopathological data: a significant decrease (p < 0.05) in the proliferation and mitotic rates and a 4.6-fold increase in the apoptotic rate. A surrogate response biomarker based on the linear combination of 12 spectral features has been found in the MRS/MRSI pattern of treated tumors, allowing the non-invasive classification of growing and responding GL261 GB. The methodology described can be applied to preclinical treatment efficacy studies to test new antitumoral drugs, and begets translational potential for early response detection in clinical studies. PMID:25208348

  2. Cloud based emergency health care information service in India.

    PubMed

    Karthikeyan, N; Sukanesh, R

    2012-12-01

    A hospital is a health care organization providing patient treatment by expert physicians, surgeons and equipments. A report from a health care accreditation group says that miscommunication between patients and health care providers is the reason for the gap in providing emergency medical care to people in need. In developing countries, illiteracy is the major key root for deaths resulting from uncertain diseases constituting a serious public health problem. Mentally affected, differently abled and unconscious patients can't communicate about their medical history to the medical practitioners. Also, Medical practitioners can't edit or view DICOM images instantly. Our aim is to provide palm vein pattern recognition based medical record retrieval system, using cloud computing for the above mentioned people. Distributed computing technology is coming in the new forms as Grid computing and Cloud computing. These new forms are assured to bring Information Technology (IT) as a service. In this paper, we have described how these new forms of distributed computing will be helpful for modern health care industries. Cloud Computing is germinating its benefit to industrial sectors especially in medical scenarios. In Cloud Computing, IT-related capabilities and resources are provided as services, via the distributed computing on-demand. This paper is concerned with sprouting software as a service (SaaS) by means of Cloud computing with an aim to bring emergency health care sector in an umbrella with physical secured patient records. In framing the emergency healthcare treatment, the crucial thing considered necessary to decide about patients is their previous health conduct records. Thus a ubiquitous access to appropriate records is essential. Palm vein pattern recognition promises a secured patient record access. Likewise our paper reveals an efficient means to view, edit or transfer the DICOM images instantly which was a challenging task for medical practitioners in the past years. We have developed two services for health care. 1. Cloud based Palm vein recognition system 2. Distributed Medical image processing tools for medical practitioners. PMID:22865161

  3. An effective procedure to create a speckle pattern on biological soft tissue for digital image correlation measurements.

    PubMed

    Lionello, Giacomo; Sirieix, Camille; Baleani, Massimiliano

    2014-11-01

    Creating a speckle pattern on biological soft tissue, which would be suitable for digital image correlation measurements, is challenging. Speckle patterns should neither cause or require sample dehydration, nor alter the mechanical response, but they should adhere to the tissue surface and withstand large deformations. A two-step procedure has been implemented to create a highly-contrasted pattern. It requires staining of the tissue with methylene blue solution to obtain a dark background and airbrushing the surface with paint to create white speckles. This study evaluated the effectiveness of the proposed procedure and whether the pattern creation had any effect on the elastic response of soft tissue. Forty porcine collateral ligaments underwent three series of cyclic tensile tests to a nominal elongation of 10% for 30 cycles. The specimen stiffness was calculated from the load-elongation curve collected during the last 10 cycles. One side of 20 ligaments was blue stained between the first and second test series, and white patterned between the second and third test series. During the last series, ligament surface images were also acquired and elaborated using the digital image correlation technique. The other 20 ligaments were untreated. The data show a small non-significant upward trend in stiffness in treated as well as in untreated ligaments (maximum increase of 1.7%). The 'successfully-correlated area' of the stereo-visible ligament surface was on average 96%, i.e. small parts of the 'stereo-visible area' were lost during computation. The described procedure is an effective method to create a pattern on biological soft tissues. PMID:25064161

  4. Remote Measurements of Snowfalls in Wakasa Bay, Japan with Airborne Millimeter- wave Imaging Radiometer and Cloud Radar

    NASA Technical Reports Server (NTRS)

    Wang, J. R.; Austin, R.; Liu, G. S.; Racette, P. E.

    2004-01-01

    In this paper we explore the application of combined millimeter-wave radar and radiometry to remotely measure snowfall. During January-February of 2003, a field campaign was conducted with the NASA P-3 aircraft in Wakasa Bay, Japan for the validation of the AMSRE microwave radiometer on board the Aqua satellite. Among the suite of instruments-on board the P-3 aircraft were the Millimeter-wave Imaging Radiometer (MIR) from the NASA Goddard Space Flight Center and the 94 GHz Airborne Cloud Radar (ACR) which is co-owned and operated by NASA Jet Propulsion Laboratory/University of Massachusetts. MIR is a total power, across-track scanning radiometer that measures radiation at the frequencies of 89, 150, 183.3 +/- 1, 183.3 +/- 3, 183.3 +/-7, 220, and 340 GHz. The MIR has flown many successful missions since its completion in May 1992. ACR is a newer instrument and flew only a few times prior to the Wakasa Bay deployment. These two instruments which are particularly well suited for the detection of snowfall functioned normally during flights over snowfall and excellent data sets were acquired. On January 14, 28, and 29 flights were conducted over snowfall events. The MIR and ACR detected strong signals during periods of snowfall over ocean and land. Results from the analysis of these concurrent data sets show that (1) the scattering of millimeter-wave radiation as detected by the MIR is strongly correlated with ACR radar reflectivity profiles, and (2) the scattering is highly frequency-dependent, the higher the frequency the stronger the scattering. Additionally, the more transparent channels of the MIR (e.g., 89, 150, and 220 GHz) are found to display ambiguous signatures of snowfall because of their exposure to surface features. Thus, the snowfall detection and retrievals of snowfall parameters, such as the ice water path (IWP) and median mass diameter (D(me)) are best conducted at the more opaque channels near 183.3 GHz and 340 GHz. Retrievals of IWP and D(me) using the MIR measurements at 183.3 and 340 GHZ are currently in progress, and the results will be compared with those derived from the ACR reflectivity profiles. Implication from this comparison will be discussed.

  5. Cloud Protocols

    NSDL National Science Digital Library

    The GLOBE Program, UCAR (University Corporation for Atmospheric Research)

    2003-08-01

    The purpose of this activity is to observe the type and cover of clouds including contrails. Students observe which of ten types of clouds and how many of three types of contrails are visible and how much of the sky is covered by clouds (other than contrails) and how much is covered by contrails. Intended outcomes are that students learn how to make estimates from observations and how to categorize specific clouds following general descriptions for the categories. They will learn the meteorological concepts of cloud heights, types, and cloud cover and learn the ten basic cloud types. Supporting background materials for both student and teacher are included.

  6. Low-level properties of natural images predict topographic patterns of neural response in the ventral visual pathway

    PubMed Central

    Andrews, Timothy J.; Watson, David M.; Rice, Grace E.; Hartley, Tom

    2015-01-01

    Neuroimaging research over the past 20 years has begun to reveal a picture of how the human visual system is organized. A key distinction that has arisen from these studies is the difference in the organization of low-level and high-level visual regions. Low-level regions contain topographic maps that are tightly linked to properties of the image. In contrast, high-level visual areas are thought to be arranged in modules that are tightly linked to categorical or semantic information in the image. To date, an unresolved question has been how the strong functional selectivity for object categories in high-level visual regions might arise from the image-based representations found in low-level visual regions. Here, we review recent evidence suggesting that patterns of response in high-level visual areas may be better explained by response to image properties that are characteristic of different object categories. PMID:26024512

  7. ISCCP Cloud Algorithm Intercomparison.

    NASA Astrophysics Data System (ADS)

    Rossow, W. B.; Mosher, F.; Kinsella, E.; Arking, A.; Desbois, M.; Harrison, E.; Minnis, P.; Ruprecht, E.; Seze, G.; Simmer, C.; Smith, E.

    1985-09-01

    The International Satellite Cloud Climatology Project (ISCCP) will provide a uniform global climatology of satellite-measured radiances and derive an experimental climatology of cloud radiative properties from these radiances. A pilot study to intercompare cloud analysis algorithms was initiated in 1981 to define a state-of-the-art algorithm for ISCCP. This study compared the results of applying six different algorithms to the same satellite radiance data. The results show that the performance of all current algorithms depends on how accurately the clear sky radiances are specified; much improvement in results is possible with better methods for obtaining these clear-sky radiances. A major difference between the algorithms is caused by their sensitivity to changes in the cloud size distribution and optical properties: all methods, which work well for some cloud types or climate regions, do poorly for other situations. Therefore, the ISCCP algorithm is composed of a series of steps, each of which is designed to detect some of the clouds present in the scene. This progressive analysis is used to retrieve an estimate of the clear sky radiances corresponding to each satellite image. Application of a bispectral threshold is then used as the last step to determine the cloud fraction. Cloudy radiances are interpreted in terms of a simplified model of cloud radiative effects to provide some measure of cloud radiative properties. Application of this experimental algorithm to produce a cloud climatology and field observation programs to validate the results will stimulate further research on cloud analysis techniques as part of ISCCP.

  8. Optimum exposure conditions for computed radiography depending on fixed pattern noise and efficiency of imaging plate-scanner systems

    SciTech Connect

    Ewert, U.; Heyne, K.; Zscherpel, U.; Jechow, M. [1 BAM Federal Institute for Materials Research and Testing, D-12205 Berlin (Germany); Bavendiek, K. [YXLON International GmbH, D-22419 Hamburg (Germany)

    2011-06-23

    The presently active standards on Computed Radiography (CR) need a major revision. It was observed by many users that the image quality for class B of EN 14784-2 is not achievable under the same exposure conditions as used for film exposure. A mathematical model was developed and tested, which allows the calculation of the image quality, proven by image quality indicators (IQI), depending on the fixed pattern noise and the efficiency of the used imaging plate (IP) scanner system. All tested IP scanner systems provide a fixed correlation between the measured signal/noise ratio (SNR) and the grey values in the digital images. The maximum achievable SNR{sub max} depends on the fixed pattern noise of the plate (high dose limit). Depending on the exposure dose an optimum visibility of IQIs can be predicted by calculation and measured considering the attenuation coefficient for calculation of the contrast/noise ratio (CNR). The diameter of the just visible wire is proportional to 1/sqrt(CNR). The optimum tube voltage for best visibility of IQIs and maximum CNR depend on the exposure dose. The optimum tube voltage for best visibility is achieved only at exposures with high dose. A dose dependant optimal tube voltage was not observed for film radiography.

  9. A spatiotemporal mining framework for abnormal association patterns in marine environments with a time series of remote sensing images

    NASA Astrophysics Data System (ADS)

    Xue, Cunjin; Song, Wanjiao; Qin, Lijuan; Dong, Qing; Wen, Xiaoyang

    2015-06-01

    A spatiotemporal mining framework is a novel tool for the analysis of marine association patterns using multiple remote sensing images. From data pretreatment, to algorithm design, to association rule mining and pattern visualization, this paper outlines a spatiotemporal mining framework for abnormal association patterns in marine environments, including pixel-based and object-based mining models. Within this framework, some key issues are also addressed. In the data pretreatment phase, we propose an algorithm for extracting abnormal objects or pixels over marine surfaces, and construct a mining transaction table with object-based and pixel-based strategies. In the mining algorithm phase, a recursion method to construct a direct association pattern tree is addressed with an asymmetric mutual information table, and a recursive mining algorithm to find frequent items. In the knowledge visualization phase, a "Dimension-Attributes" visualization framework is used to display spatiotemporal association patterns. Finally, spatiotemporal association patterns for marine environmental parameters in the Pacific Ocean are identified, and the results prove the effectiveness and the efficiency of the proposed mining framework.

  10. GEWEX cloud assessment: A review

    NASA Astrophysics Data System (ADS)

    Stubenrauch, Claudia; Rossow, William B.; Kinne, Stefan; Ackerman, Steve; Cesana, Gregory; Chepfer, Hélène; Di Girolamo, Larry; Getzewich, Brian; Guignard, Anthony; Heidinger, Andy; Maddux, Brent; Menzel, Paul; Minnis, Patrick; Pearl, Cindy; Platnick, Steven; Poulsen, Caroline; Riedi, Jérôme; Sayer, Andrew; Sun-Mack, Sunny; Walther, Andi; Winker, Dave; Zeng, Shen; Zhao, Guangyu

    2013-05-01

    Clouds cover about 70% of the Earth's surface and play a dominant role in the energy and water cycle of our planet. Only satellite observations provide a continuous survey of the state of the atmosphere over the entire globe and across the wide range of spatial and temporal scales that comprise weather and climate variability. Satellite cloud data records now exceed more than 25 years; however, climatologies compiled from different satellite datasets can exhibit systematic biases. Questions therefore arise as to the accuracy and limitations of the various sensors. The Global Energy and Water cycle Experiment (GEWEX) Cloud Assessment, initiated in 2005 by the GEWEX Radiation Panel, provides the first coordinated intercomparison of publicly available, global cloud products (gridded, monthly statistics) retrieved from measurements of multi-spectral imagers (some with multi-angle view and polarization capabilities), IR sounders and lidar. Cloud properties under study include cloud amount, cloud height (in terms of pressure, temperature or altitude), cloud radiative properties (optical depth or emissivity), cloud thermodynamic phase and bulk microphysical properties (effective particle size and water path). Differences in average cloud properties, especially in the amount of high-level clouds, are mostly explained by the inherent instrument measurement capability for detecting and/or identifying optically thin cirrus, especially when overlying low-level clouds. The study of long-term variations with these datasets requires consideration of many factors. The monthly, gridded database presented here facilitates further assessments, climate studies, and the evaluation of climate models.

  11. Brain activation pattern during a verbal fluency test in healthy male and female volunteers: a functional magnetic resonance imaging study.

    PubMed

    Weiss, E M; Siedentopf, C; Hofer, A; Deisenhammer, E A; Hoptman, M J; Kremser, C; Golaszewski, S; Felber, S; Fleischhacker, W W; Delazer, M

    2003-12-11

    Sex differences in executive speech tasks, favoring women, have been noted in behavioral studies and functional imaging studies. In the present study ten female and ten male volunteers underwent functional magnetic resonance imaging in a conventional block design. All subjects were selected on the basis of high performance on the verbal fluency task. Regions of activation were detected after performance of a covert lexical verbal fluency task inside the scanner. Men and women who did not differ significantly in verbal fluency task performance showed a very similar pattern of brain activation. Our data argue against genuine between-sex differences in cerebral activation patterns during lexical verbal fluency activities when confounding factors like performance differences are excluded. PMID:14625017

  12. DEEP NEAR-INFRARED IMAGING OF THE {rho} Oph CLOUD CORE: CLUES TO THE ORIGIN OF THE LOWEST-MASS BROWN DWARFS

    SciTech Connect

    Marsh, Kenneth A.; Plavchan, Peter; Kirkpatrick, J. Davy; Lowrance, Patrick J.; Cutri, Roc M. [Infrared Processing and Analysis Center, California Institute of Technology 100-22, Pasadena, CA 91125 (United States); Velusamy, Thangasamy, E-mail: kam@ipac.caltech.ed, E-mail: plavchan@ipac.caltech.ed, E-mail: davy@ipac.caltech.ed, E-mail: lowrance@ipac.caltech.ed, E-mail: roc@ipac.caltech.ed, E-mail: Thangasamy.Velusamy@jpl.nasa.go [Jet Propulsion Laboratory, MS 169-506, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2010-08-10

    A search for young substellar objects in the {rho} Oph cloud core region has been made with the aid of multiband profile-fitting point-source photometry of the deep-integration Combined Calibration Scan images of the 2MASS extended mission in the J, H, and K{sub s} bands, and Spitzer IRAC images at 3.6, 4.5, 5.8, and 8.0 {mu}m. The field of view of the combined observations was 1{sup 0} x 9.'3, and the 5{sigma} limiting magnitude at J was 20.5. Comparison of the observed spectral energy distributions with the predictions of the COND and DUSTY models, for an assumed age of 1 Myr, supports the identification of many of the sources with brown dwarfs and enables the estimation of effective temperature, T {sub eff}. The cluster members are then readily distinguishable from background stars by their locations on a plot of flux density versus T {sub eff}. The range of estimated T {sub eff} values extends down to {approx}750 K which, based on the COND model, would suggest the presence of objects of sub-Jupiter mass. The results also suggest that the mass function for the {rho} Oph cloud resembles that of the {sigma} Orionis cluster based on a recent study, with both rising steadily toward lower masses. The other main result from our study is the apparent presence of a progressive blueward skew in the distribution of J - H and H - K{sub s} colors, such that the blue end of the range becomes increasingly bluer with increasing magnitude. We suggest that this behavior might be understood in terms of the 'ejected stellar embryo' hypothesis, whereby some of the lowest-mass brown dwarfs could escape to locations close to the front edge of the cloud, and thereby be seen with less extinction.

  13. Spatial pattern alterations from JPEG2000 lossy compression of remote sensing images: massive variogram analysis in high performance computing

    NASA Astrophysics Data System (ADS)

    Pesquer, Lluís; Pons, Xavier; Cortés, Ana; Serral, Ivette

    2013-01-01

    We evaluate the implications of JPEG2000 lossy compression of remote sensing images for spatial analytical purposes. The main issue is to identify which cases and conditions in geostatistical studies are suitable for using lossy compressed images. For these purposes, an extensive test using Landsat, compact airborne spectrographic imager (CASI), and moderate resolution imaging spectroradiometer (MODIS) image series has been analyzed, through applying and comparing two-dimensional and three-dimensional (spectral and time domains) compression methods with a wide range of compression ratios for several dates, different landscape regions, and spectral bands. Due to the massive test bed and consequently to the high time consuming executions, a parallel solution was specifically developed. Variogram analyses showed that all the compression ratios maintain the variogram shapes, but high compression ratios (>20?1) degrade the spatial patterns of the remote sensing images. These alterations are lower for the three-dimensional compression method, which was a considerable improvement (25%) on the two-dimensional method for large three-dimensional series (CASI, MODIS). However, the two methods behave similarly in the Landsat case. Finally, the parallel solution in a distributed environment demonstrates that high performance computing offers a suitable scientific platform for highly demanding time execution applications, such as geostatistical analyses of remote sensing images.

  14. Vibration Pattern Imager (VPI): A control and data acquisition system for scanning laser vibrometers

    NASA Technical Reports Server (NTRS)

    Rizzi, Stephen A.; Brown, Donald E.; Shaffer, Thomas A.

    1993-01-01

    The Vibration Pattern Imager (VPI) system was designed to control and acquire data from scanning laser vibrometer sensors. The PC computer based system uses a digital signal processing (DSP) board and an analog I/O board to control the sensor and to process the data. The VPI system was originally developed for use with the Ometron VPI Sensor, but can be readily adapted to any commercially available sensor which provides an analog output signal and requires analog inputs for control of mirror positioning. The sensor itself is not part of the VPI system. A graphical interface program, which runs on a PC under the MS-DOS operating system, functions in an interactive mode and communicates with the DSP and I/O boards in a user-friendly fashion through the aid of pop-up menus. Two types of data may be acquired with the VPI system: single point or 'full field.' In the single point mode, time series data is sampled by the A/D converter on the I/O board (at a user-defined sampling rate for a selectable number of samples) and is stored by the PC. The position of the measuring point (adjusted by mirrors in the sensor) is controlled via a mouse input. The mouse input is translated to output voltages by the D/A converter on the I/O board to control the mirror servos. In the 'full field' mode, the measurement point is moved over a user-selectable rectangular area. The time series data is sampled by the A/D converter on the I/O board (at a user-defined sampling rate for a selectable number of samples) and converted to a root-mean-square (rms) value by the DSP board. The rms 'full field' velocity distribution is then uploaded for display and storage on the PC.

  15. Time-resolved imaging of the MALDI linear-TOF ion cloud: direct visualization and exploitation of ion optical phenomena using a position- and time-sensitive detector.

    PubMed

    Ellis, Shane R; Soltwisch, Jens; Heeren, Ron M A

    2014-05-01

    In this study, we describe the implementation of a position- and time-sensitive detection system (Timepix detector) to directly visualize the spatial distributions of the matrix-assisted laser desorption ionization ion cloud in a linear-time-of-flight (MALDI linear-ToF) as it is projected onto the detector surface. These time-resolved images allow direct visualization of m/z-dependent ion focusing effects that occur within the ion source of the instrument. The influence of key parameters, namely extraction voltage (E(V)), pulsed-ion extraction (PIE) delay, and even the matrix-dependent initial ion velocity was investigated and were found to alter the focusing properties of the ion-optical system. Under certain conditions where the spatial focal plane coincides with the detector plane, so-called x-y space focusing could be observed (i.e., the focusing of the ion cloud to a small, well-defined spot on the detector). Such conditions allow for the stigmatic ion imaging of intact proteins for the first time on a commercial linear ToF-MS system. In combination with the ion-optical magnification of the system (~100×), a spatial resolving power of 11–16 ?m with a pixel size of 550 nm was recorded within a laser spot diameter of ~125 ?m. This study demonstrates both the diagnostic and analytical advantages offered by the Timepix detector in ToF-MS. PMID:24658803

  16. Deep Near-Infrared Imaging of the rho Oph Cloud Core: Clues to the Origin of the Lowest-Mass Brown Dwarfs

    E-print Network

    Marsh, Kenneth A; Kirkpatrick, J Davy; Lowrance, Patrick J; Cutri, Roc M; Velusamy, Thangasamy

    2010-01-01

    A search for young substellar objects in the rho Oph cloud core region has been made using the deep-integration Combined Calibration Scan images of the 2MASS extended mission in J, H and Ks bands, and Spitzer IRAC images at 3.6, 4.5, 5.8 and 8.0 microns. The field of view of the combined observations was 1 deg x 9.3 arcmin, and the 5 sigma limiting magnitude at J was 20.5. Comparison of the observed SEDs with the predictions of the COND and DUSTY models, for an assumed age of 1 Myr, supports the identification of many of the sources with brown dwarfs, and enables the estimation of effective temperature, Teff. The cluster members are then readily distinguishable from background stars by their locations on a plot of flux density versus Teff. The range of estimated Teff extends down to ~ 750 K, suggesting the presence of objects of sub-Jupiter mass. The results also suggest that the mass function for the rho Oph cloud resembles that of the sigma Orionis cluster based on a recent study, with both rising towards l...

  17. Block-based cloud classification with statistical features and distribution of local texture features

    NASA Astrophysics Data System (ADS)

    Cheng, H.-Y.; Yu, C.-C.

    2015-03-01

    This work performs cloud classification on all-sky images. To deal with mixed cloud types in one image, we propose performing block division and block-based classification. In addition to classical statistical texture features, the proposed method incorporates local binary pattern, which extracts local texture features in the feature vector. The combined feature can effectively preserve global information as well as more discriminating local texture features of different cloud types. The experimental results have shown that applying the combined feature results in higher classification accuracy compared to using classical statistical texture features. In our experiments, it is also validated that using block-based classification outperforms classification on the entire images. Moreover, we report the classification accuracy using different classifiers including the k-nearest neighbor classifier, Bayesian classifier, and support vector machine.

  18. A Tool for Classifying Individuals with Chronic Back Pain: Using Multivariate Pattern Analysis with Functional Magnetic Resonance Imaging Data

    PubMed Central

    Callan, Daniel; Mills, Lloyd; Nott, Connie; England, Robert; England, Shaun

    2014-01-01

    Chronic pain is one of the most prevalent health problems in the world today, yet neurological markers, critical to diagnosis of chronic pain, are still largely unknown. The ability to objectively identify individuals with chronic pain using functional magnetic resonance imaging (fMRI) data is important for the advancement of diagnosis, treatment, and theoretical knowledge of brain processes associated with chronic pain. The purpose of our research is to investigate specific neurological markers that could be used to diagnose individuals experiencing chronic pain by using multivariate pattern analysis with fMRI data. We hypothesize that individuals with chronic pain have different patterns of brain activity in response to induced pain. This pattern can be used to classify the presence or absence of chronic pain. The fMRI experiment consisted of alternating 14 seconds of painful electric stimulation (applied to the lower back) with 14 seconds of rest. We analyzed contrast fMRI images in stimulation versus rest in pain-related brain regions to distinguish between the groups of participants: 1) chronic pain and 2) normal controls. We employed supervised machine learning techniques, specifically sparse logistic regression, to train a classifier based on these contrast images using a leave-one-out cross-validation procedure. We correctly classified 92.3% of the chronic pain group (N?=?13) and 92.3% of the normal control group (N?=?13) by recognizing multivariate patterns of activity in the somatosensory and inferior parietal cortex. This technique demonstrates that differences in the pattern of brain activity to induced pain can be used as a neurological marker to distinguish between individuals with and without chronic pain. Medical, legal and business professionals have recognized the importance of this research topic and of developing objective measures of chronic pain. This method of data analysis was very successful in correctly classifying each of the two groups. PMID:24905072

  19. A lossy\\/lossless compression method for printed typeset bi-level text images based on improved pattern matching

    Microsoft Academic Search

    Hadi Grailu; Mojtaba Lotfizad; Hadi Sadoghi Yazdi

    2009-01-01

    Pattern matching is the most widely used technique for the compression of printed bi-level text images. In some printed scripts,\\u000a letters normally attach to each other, or some letters have a simple relation to each other, or there may be undesired touching\\u000a characters. Detecting such situations and exploiting them to reduce the library size, has a rather great effect on

  20. Multiphoton microscopy for imaging infectious keratitis: demonstration of the pattern of microbial spread in an experimental model

    NASA Astrophysics Data System (ADS)

    Sun, Yen; Lo, Wen; Wu, Ruei-Jhih; Lin, Sung-Jan; Lin, Wei-Chou; Jee, Shiou-Hwa; Tan, Hsin-Yuan; Dong, Chen-Yuan

    2006-02-01

    The purpose of this study is to assess the application of multiphoton fluorescence and second harmonic generation (SHG) microscopy for imaging and monitoring the disease progress of infectious keratitis in an experimental model, and to investigate the possible correlation of tissue architecture with spreading patterns of pathogens in an experimental model. Porcine eyes are to be obtained from slaughter house and processed and placed in organ culture system. Fungal infections by common pathogens of infectious keratitis are to be induced in porcine cornea buttons. Multiphoton fluorescence and SHG microscopy will be used for imaging and for monitoring the progression and extension of tissue destruction and possibly the pattern of pathogen spreading. We found that SHG imaging is useful in identifying alterations to collagen architecture while autofluorescence microscopy can be used to visualize the fungi and cells within the stroma. In summary, multiphoton fluorescence and second harmonic generation microscopy can non-invasively demonstrate and monitor tissue destruction associated with infectious keratitis. The pattern of pathogen spreading and its correlation with the tissue architecture can also be shown, which can be useful for future studies of the tissue-microbial interactions for infectious keratitis.

  1. Retinal hemorrhage and brain injury patterns on diffusion-weighted magnetic resonance imaging in children with head trauma

    PubMed Central

    Binenbaum, Gil; Christian, Cindy W.; Ichord, Rebecca N.; Ying, Guishaung; Simon, Melissa A.; Romero, Kathleen; Pollock, Avrum N.; Forbes, Brian J.

    2013-01-01

    Purpose To evaluate associations between retinal hemorrhage severity and hypoxic-ischemic brain injury (HII) patterns by diffusion-weighted magnetic resonance imaging (DW-MRI) in young children with head trauma. Methods DW-MRI images of a consecutive cohort study of children under age 3 years with inflicted or accidental head trauma who had eye examinations were analyzed by two independent masked examiners for type, severity, and location of primary lesions attributable to trauma, HII secondary to trauma, and mixed injury patterns. Retinal hemorrhage was graded retrospectively on a scale from 1 (none) to 5 (severe). Results Retinal hemorrhage score was 3–5 in 6 of 7 patients with predominantly post-traumatic HII pattern and 4 of 32 who had traumatic injury without HII (P < 0.001) on DW-MRI imaging. Severe retinal hemorrhage was observed in absence of HII but only in inflicted injury. Retinal hemorrhage severity was correlated with HII severity (? = 0.53, P < 0.001) but not traumatic injury severity (? = ?0.10, P = 0.50). HII severity was associated with retinal hemorrhage score 3–5 (P = 0.01), but traumatic injury severity was not (P = 0.37). Conclusions During inflicted head injury, a distinct type of trauma occurs causing more global brain injury with HII and more severe retinal hemorrhages. HII is not a necessary factor for severe retinal hemorrhage to develop from inflicted trauma. PMID:24215807

  2. WW2010: Clouds and Precipitation

    NSDL National Science Digital Library

    Daniel Bramer

    1997-01-01

    This site covers many of the components of cloud formation and cloud types. Although written for the high school level, the middle school student could grasp most of the concepts with the assistance from the teacher. Specific concepts covered include the importance of and mechanisms that produce rising air, cloud types, and ptyes of precipitation. There are nice graphics and images to support the text.

  3. INFRARED IMAGING OF THE LARGE MAGELLANIC CLOUD STARFORMING REGION HENIZE 206 V. Gorjian and M W. Werner

    E-print Network

    De Buizer, James Michael

    .O. Box 26732, 950 North Cherry Avenue, Tucson, AZ 85726­6732 K. D. Gordon, J. Muzzerole, and J. Morrison; accepted 2004 May 21 ABSTRACT Henize 206 is a region of star formation in the Large Magellanic Cloud star formation. The radiation from young stars has excited strong polycyclic aromatic hydrocarbon (PAH

  4. INFRARED IMAGING OF THE LARGE MAGELLANIC CLOUD STAR-FORMING REGION HENIZE 206 V. Gorjian and M W. Werner

    E-print Network

    De Buizer, James Michael

    .O. Box 26732, 950 North Cherry Avenue, Tucson, AZ 85726-6732 K. D. Gordon, J. Muzzerole, and J. Morrison; accepted 2004 May 21 ABSTRACT Henize 206 is a region of star formation in the Large Magellanic Cloud star formation. The radiation from young stars has excited strong polycyclic aromatic hydrocarbon (PAH

  5. Opaque cloud detection

    DOEpatents

    Roskovensky, John K. (Albuquerque, NM)

    2009-01-20

    A method of detecting clouds in a digital image comprising, for an area of the digital image, determining a reflectance value in at least three discrete electromagnetic spectrum bands, computing a first ratio of one reflectance value minus another reflectance value and the same two values added together, computing a second ratio of one reflectance value and another reflectance value, choosing one of the reflectance values, and concluding that an opaque cloud exists in the area if the results of each of the two computing steps and the choosing step fall within three corresponding predetermined ranges.

  6. Improvement of temporal resolution in blood concentration imaging using NIR speckle patterns

    NASA Astrophysics Data System (ADS)

    Yokoi, Naomichi; Shimatani, Yuichi; Kyoso, Masaki; Funamizu, Hideki; Aizu, Yoshihisa

    2013-06-01

    In the imaging of blood concentration change using near infrared bio-speckles, temporal averaging of speckle images is necessary for speckle reduction. To improve the temporal resolution in blood concentration imaging, use of spatial averaging is investigated to measured data in rat experiments. Results show that three frames in temporal averaging with (2×2) pixels in spatial averaging can be accepted to obtain the temporal resolution of ten concentration images per second.

  7. Preliminary validation of a new variable pattern for daily quality assurance of medical image display devices

    Microsoft Academic Search

    Jurgen Jacobs; Frank Rogge; John Kotre; Guy Marchal; Hilde Bosmans

    2007-01-01

    This paper reports on a comparative study between the well-established test patterns for daily quality assurance (QA) of monitors of the American Association of Medical Physicists, Task Group 18 (AAPMtg18) and the Deutsches Institut fuer Normung e.V (DIN), and a newly proposed variable test pattern. A characteristic of the test patterns currently used for the QA of monitors is their

  8. An Automatic Method for the Removal of Unwanted, Nonperiodic Patterns from Forensic Images

    E-print Network

    Zisserman, Andrew

    the latent mark. The registration of the images involves both a geometric and a photometric component, fingerprints, latent marks, image registration, photometric registration, spatial defor­ mations 1 image) contains the latent mark which we aim to separate from its non­periodic background. The second

  9. Patterns of Image Comparison Using Compare and Contrast Feature in Urinalysis Tutor(TM).

    ERIC Educational Resources Information Center

    Kim, Sara; Astion, Michael

    2000-01-01

    Examines how students interacted with a computer-based feature in Urinalysis Tutor(TM), "Compare and Contrast," which facilitated image comparisons. Three main image-viewing modes emerged. Overall, anchored viewing was the predominant image-viewing mode. Results suggest that a computer instructional program with a user-controlled interactivity…

  10. Observing the invisible through imaging mass spectrometry, a window into the metabolic exchange patterns of microbes

    E-print Network

    Nizet, Victor

    that MALDI-imaging mass spectrometry can be adapted to observe, in a spatial manner, the metabolic exchangeObserving the invisible through imaging mass spectrometry, a window into the metabolic exchange, rapamycin, epothilone). In this article, written for a special issue on imaging mass spectrometry, we show

  11. Modeling the optical characteristics of lightning pulses scattered through the cloud to the upper surface

    NASA Astrophysics Data System (ADS)

    Finke, U.

    2011-12-01

    The future Meteosat Third Generation (MTG) will carry the Lightning Imager (LI) - an optical instrument for lightning detection from the geostationary orbit. This instrument will observe the optical signal which originates from the lightning discharge. Since lightning is located in and below the cloud the signal which can be detected on the upper surface is the result of a multiple scattering process of light on the cloud particles. The resulting signal on the upper cloud surface is delayed and broadened in time and blurred in space. For the optimal design of the instrument and for the interpretation of the future data it is important to understand and to reproduce these scattering processes. This transport of light through the cloud is modeled for a sufficiently dense cloud both analytically and by a Monte-Carlo-simulation. The resulting pulse shape and pattern for the various parameters are compared against observations made by air-borne and satellite-borne instruments. The quantitative dependency of output parameters such as the upwelling energy fraction, the optical pattern size from the source and cloud parameters are established and discussed. The driving parameters are the source location in and below the cloud and the cloud's scattering properties given by the local optical depth and the cloud shape. Particularly, the effects of irregular cloud shape and sizes, and inhomogeneous particle size and distribution are discussed. This is of interest, since for the geostationary observation a significant part of the field of view is observed with large satellite viewing angles. These resulting geometric distortions are discussed.

  12. Advanced 3-D analysis, client-server systems, and cloud computing-Integration of cardiovascular imaging data into clinical workflows of transcatheter aortic valve replacement.

    PubMed

    Schoenhagen, Paul; Zimmermann, Mathis; Falkner, Juergen

    2013-06-01

    Degenerative aortic stenosis is highly prevalent in the aging populations of industrialized countries and is associated with poor prognosis. Surgical valve replacement has been the only established treatment with documented improvement of long-term outcome. However, many of the older patients with aortic stenosis (AS) are high-risk or ineligible for surgery. For these patients, transcatheter aortic valve replacement (TAVR) has emerged as a treatment alternative. The TAVR procedure is characterized by a lack of visualization of the operative field. Therefore, pre- and intra-procedural imaging is critical for patient selection, pre-procedural planning, and intra-operative decision-making. Incremental to conventional angiography and 2-D echocardiography, multidetector computed tomography (CT) has assumed an important role before TAVR. The analysis of 3-D CT data requires extensive post-processing during direct interaction with the dataset, using advance analysis software. Organization and storage of the data according to complex clinical workflows and sharing of image information have become a critical part of these novel treatment approaches. Optimally, the data are integrated into a comprehensive image data file accessible to multiple groups of practitioners across the hospital. This creates new challenges for data management requiring a complex IT infrastructure, spanning across multiple locations, but is increasingly achieved with client-server solutions and private cloud technology. This article describes the challenges and opportunities created by the increased amount of patient-specific imaging data in the context of TAVR. PMID:24282750

  13. Uncertainty of Passive Imager Cloud Optical Property Retrievals to Instrument Radiometry and Model Assumptions: Examples from MODIS

    NASA Technical Reports Server (NTRS)

    Platnick, Steven; Wind, Galina; Meyer, Kerry; Amarasinghe, Nandana; Arnold, G. Thomas; Zhang, Zhibo; King, Michael D.

    2013-01-01

    The optical and microphysical structure of clouds is of fundamental importance for understanding a variety of cloud radiation and precipitation processes. With the advent of MODIS on the NASA EOS Terra and Aqua platforms, simultaneous global-daily 1 km retrievals of cloud optical thickness (COT) and effective particle radius (CER) are provided, as well as the derived water path (WP). The cloud product (MOD06/MYD06 for MODIS Terra and Aqua, respectively) provides separate retrieval datasets for various two-channel retrievals, typically a VISNIR channel paired with a 1.6, 2.1, and 3.7 m spectral channel. The MOD06 forward model is derived from on a homogeneous plane-parallel cloud. In Collection 5 processing (completed in 2007 with a modified Collection 5.1 completed in 2010), pixel-level retrieval uncertainties were calculated for the following non-3-D error sources: radiometry, surface spectral albedo, and atmospheric corrections associated with model analysis uncertainties (water vapor only). The latter error source includes error correlation across the retrieval spectral channels. Estimates of uncertainty in 1 aggregated (Level-3) means were also provided assuming unity correlation between error sources for all pixels in a grid for a single day, and zero correlation of error sources from one day to the next. I n Collection 6 (expected to begin in late summer 2013) we expanded the uncertainty analysis to include: (a) scene-dependent calibration uncertainty that depends on new band and detector-specific Level 1B uncertainties, (b) new model error sources derived from the look-up tables which includes sensitivities associated with wind direction over the ocean and uncertainties in liquid water and ice effective variance, (c) thermal emission uncertainties in the 3.7 m band associated with cloud and surface temperatures that are needed to extract reflected solar radiation from the total radiance signal, (d) uncertainty in the solar spectral irradiance at 3.7 m, and (e) addition of stratospheric ozone uncertainty in visible atmospheric corrections. A summary of the approach and example Collection 6 results will be shown.

  14. Cloud Diagram

    NSDL National Science Digital Library

    This interactive diagram shows the various types of clouds and the relative altitudes at which they occur. Users can roll their mice over each cloud type and see a photo and a brief written description of each type.

  15. Cloud Computing

    SciTech Connect

    Pete Beckman and Ian Foster

    2009-12-04

    Chicago Matters: Beyond Burnham (WTTW). Chicago has become a world center of "cloud computing." Argonne experts Pete Beckman and Ian Foster explain what "cloud computing" is and how you probably already use it on a daily basis.

  16. A neural network for unsupervised categorization of multivalued input patterns: an application to satellite image clustering

    Microsoft Academic Search

    Andrea Baraldi; Flavio Parmiggiani

    1995-01-01

    Presents an implementation of an artificial neural network (ANN) which performs unsupervised detection of recognition categories from arbitrary sequences of multivalued input patterns. The proposed ANN is called Simplified Adaptive Resonance Theory Neural Network (SARTNN). First, an Improved Adaptive Resonance Theory 1 (IART1)-based neural network for binary pattern analysis is discussed and a Simplified ART1 (SART1) model is proposed. Second,

  17. The Birth of the Solar System in a Molecular Cloud: Evidence from the Isotopic Pattern of Short-lived Nuclides in the Early Solar System

    NASA Astrophysics Data System (ADS)

    Jacobsen, S. B.

    2005-12-01

    A good positive correlation between the initial solar abundances of short-lived (now extinct) nuclides (when normalized to their nucleosynthetic production ratios) and their mean lifetimes on a logarithmic plot has been well known for some time. Here I show that: (i) the slope for short-lived nuclides in the average interstellar medium in such a diagram is always 1. (ii) for molecular clouds, the slope is expected to be 2 or slightly less than 2 for a model where the molecular clouds are at a steady state and slowly exchange matter with the remaining interstellar medium. The existing data suggest a residence time of ˜ 6 x107 yrs for the matter present in molecular clouds. (iii) the intercept depends on (1) the residence time of matter in molecular clouds, (2) the mass fraction of the interstellar medium that is in molecular clouds, (3) the age of the galaxy and (4) the ratio of the time-average nucleosynthtic production rate and the production rate at the time of solar system formation. (iv) the abundances of 53Mn, 182Hf, 244Pu and 146Sm in the early solar system are likely formed by the same type of supernova sources (SNII?) over the history of our galaxy, while 129I (and possibly 107Pd) were produced in a different type of supernova sources (SNIa?) with the production rate skewed toward the early history of our galaxy. The abundances of these nuclides most likely characterize the average ISM values modified during their residence in the molecular cloud complex where the solar system formed. The abundances of 26Al, 41 Ca and 60Fe are too high to be of galactic production; these must be a contamination from young stellar sources that formed within the proto-Solar molecular cloud. These young sources could not have contributed significant quantities of 53Mn, 182Hf, 244Pu and 146Sm or 129I and thus were dissimilar to typical supernova sources.

  18. Cloud Watch

    NSDL National Science Digital Library

    The GLOBE Program, UCAR (University Corporation for Atmospheric Research)

    2003-08-01

    The purpose of this activity is to explore the connections between cloud type, cloud cover, and weather and stimulate student interest in taking cloud type observations. Students observe cloud type and coverage and weather conditions over a five-day period and correlate these observations. Students make and test predictions using these observations. The intended outcome is that students learn to draw inferences from observations and use them to make and test predictions.

  19. Forecasting precipitable water vapor and cirrus cloud cover for astronomical observatories: satellite image processing guided by synoptic model dissemination data

    NASA Astrophysics Data System (ADS)

    Erasmus, D. Andre; Sarazin, Marc S.

    2001-01-01

    Astronomical observatories are extremely dependent on sky transparency. As the expensive new very large telescopes enter into operation, flexible observing modes are being introduced, which allow each 'observing block' to be scheduled at the most appropriate time. In such modes, it makes sense to develop tools for forecasting ambient conditions. We present here the operational water vapor and cirrus cloud forecast model developed for ESO observatories in Northern Chile.

  20. Cloud Types

    NSDL National Science Digital Library

    2005-01-01

    This resource describes cloud formation and explains atmospheric processes such as convection, evaporation, and transpiration. The discussion includes how clouds form, some of their properties, and how precipitation is triggered. A multimedia interactive feature explains how clouds are named and identified. Questions for discussion are provided.

  1. A new look at the Saturn system - The Voyager 2 images

    Microsoft Academic Search

    B. A. Smith; L. Soderblom; R. M. Batson; P. M. Bridges; J. L. Inge; H. Masursky; E. Shoemaker; R. F. Beebe; J. Boyce; G. Briggs; A. Bunker; S. A. Collins; C. J. HANSEN; T. V. Johnson; J. L. Mitchell; R. J. Terrile; A. F. Cook; J. N. Cuzzi; J. B. Pollack; G. E. Danielson; A. P. Ingersoll; M. E. Davies; G. E. Hunt; D. Morrison; T. Owen; C. Sagan; J. Veverka; R. Strom; V. E. Suomi

    1982-01-01

    Images of the Saturn system acquired by Voyager 2 in its encounter in August 1981 are presented and information gained from the imagery on the atmosphere, satellites, and rings of Saturn is discussed. The images have shown the Saturn atmosphere to contain persistent oval clouds similar to those of Jupiter, and small irregular features indicative of a pattern of zonal

  2. THE REMARKABLE HIGH PRESSURE OF THE LOCAL LEO COLD CLOUD

    SciTech Connect

    Meyer, David M. [Center for Interdisciplinary Exploration and Research in Astrophysics, Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Lauroesch, J. T. [Department of Physics and Astronomy, University of Louisville, Louisville, KY 40292 (United States); Peek, J. E. G. [Department of Astronomy, Columbia University, Pupin Physics Laboratories, 550 West 120th Street, New York, NY 10027 (United States); Heiles, Carl, E-mail: davemeyer@northwestern.edu, E-mail: jtlaur01@louisville.edu, E-mail: goldston@gmail.com, E-mail: heiles@astro.berkeley.edu [Department of Astronomy, University of California, Berkeley, 601 Campbell Hall, Berkeley, CA 94720 (United States)

    2012-06-20

    Using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope, we have obtained high-resolution ultraviolet spectra of the C I absorption toward two stars behind the Local Leo Cold Cloud (LLCC). At a distance ( Almost-Equal-To 20 pc) that places it well inside the Local Bubble, the LLCC is the nearest example of the coldest known (T Almost-Equal-To 20 K) diffuse interstellar clouds. The STIS measurements of the C I fine-structure excitation toward HD 85259 and HD 83023 indicate that the thermal gas pressure of the LLCC is much greater than that of the warm clouds in the Local Bubble. The mean LLCC pressure measured toward these two stars (60,000 cm{sup -3} K) implies an H I density of Almost-Equal-To 3000 cm{sup -3} and a cloud thickness of Almost-Equal-To 200 AU at the 20 K cloud temperature. Such a thin, cold, dense structure could arise at the collision interface between converging flows of warm gas. However, the measured LLCC pressure is appreciably higher than that expected in the colliding-cloud interpretation given the velocity and column density constraints on warm clouds in the HD 85259 and HD 83023 sightlines. Additional STIS measurements of the Zn II, Ni II, and Cr II column densities toward HD 85259 indicate that the LLCC has a modest 'warm cloud' dust depletion pattern consistent with its low dust-to-gas ratio determined from H I 21 cm and 100 {mu}m observations. In support of the inferred sheet-like geometry for the LLCC, a multi-epoch comparison of the Na I absorption toward a high-proper-motion background star reveals a 40% column density variation indicative of LLCC Na I structure on a scale of Almost-Equal-To 50 AU.

  3. Cloud Radiative Effect in dependence on Cloud Type

    NASA Astrophysics Data System (ADS)

    Aebi, Christine; Gröbner, Julian; Kämpfer, Niklaus; Vuilleumier, Laurent

    2015-04-01

    Radiative transfer of energy in the atmosphere and the influence of clouds on the radiation budget remain the greatest sources of uncertainty in the simulation of climate change. Small changes in cloudiness and radiation can have large impacts on the Earth's climate. In order to assess the opposing effects of clouds on the radiation budget and the corresponding changes, frequent and more precise radiation and cloud observations are necessary. The role of clouds on the surface radiation budget is studied in order to quantify the longwave, shortwave and the total cloud radiative forcing in dependence on the atmospheric composition and cloud type. The study is performed for three different sites in Switzerland at three different altitude levels: Payerne (490 m asl), Davos (1'560 m asl) and Jungfraujoch (3'580 m asl). On the basis of data of visible all-sky camera systems at the three aforementioned stations in Switzerland, up to six different cloud types are distinguished (Cirrus-Cirrostratus, Cirrocumulus-Altocumulus, Stratus-Altostratus, Cumulus, Stratocumulus and Cumulonimbus-Nimbostratus). These cloud types are classified with a modified algorithm of Heinle et al. (2010). This cloud type classifying algorithm is based on a set of statistical features describing the color (spectral features) and the texture of an image (textural features) (Wacker et al. (2015)). The calculation of the fractional cloud cover information is based on spectral information of the all-sky camera data. The radiation data are taken from measurements with pyranometers and pyrgeometers at the different stations. A climatology of a whole year of the shortwave, longwave and total cloud radiative effect and its sensitivity to integrated water vapor, cloud cover and cloud type will be calculated for the three above-mentioned stations in Switzerland. For the calculation of the shortwave and longwave cloud radiative effect the corresponding cloud-free reference models developed at PMOD/WRC will be used (Wacker et al. (2013)). References: Heinle, A., A. Macke and A. Srivastav (2010) Automatic cloud classification of whole sky images, Atmospheric Measurement Techniques. Wacker, S., J. Gröbner and L. Vuilleumier (2013) A method to calculate cloud-free long-wave irradiance at the surface based on radiative transfer modeling and temperature lapse rate estimates, Theoretical and Applied Climatology. Wacker, S., J. Gröbner, C. Zysset, L. Diener, P. Tzoumanikis, A. Kazantzidis, L. Vuilleumier, R. Stöckli, S. Nyeki, and N. Kämpfer (2015) Cloud observations in Switzerland using hemispherical sky cameras, Journal of Geophysical Research.

  4. A novel biosensor array with a wheel-like pattern for glucose, lactate and choline based on electrochemiluminescence imaging.

    PubMed

    Zhou, Zhenyu; Xu, Linru; Wu, Suozhu; Su, Bin

    2014-10-01

    Electrochemiluminescence (ECL) imaging provides a superior approach to achieve array detection because of its ability for ultrasensitive multiplex analysis. In this paper, we reported a novel ECL imaging biosensor array modified with an enzyme/carbon nanotubes/chitosan composite film for the determination of glucose, choline and lactate. The biosensor array was constructed by integrating a patterned indium tin oxide (ITO) glass plate with six perforated poly(dimethylsiloxane) (PDMS) covers. ECL is generated by the electrochemical reaction between luminol and hydrogen peroxide that is produced by the enzyme catalysed oxidation of different substrates with molecular oxygen, and ECL images were captured by a charge-coupled device (CCD) camera. The separated electrochemical micro-cells enabled simultaneous assay of six samples at different concentrations. From the established calibration curves, the detection limits were 14 ?M for glucose, 40 ?M for lactate and 97 ?M for choline, respectively. Moreover, multicomponent assays and cross reactivity were also studied, both of which were satisfied for the analysis. This biosensing platform based on ECL imaging shows many distinct advantages, including miniaturization, low cost, and multi-functionalization. We believe that this novel ECL imaging biosensor platform will have potential applications in clinical diagnostics, medicine and food inspection. PMID:25068822

  5. Observe clouds form and dissipate

    NSDL National Science Digital Library

    TERC. Center for Earth and Space Science Education

    2003-01-01

    This animation presents a time-lapse sequence of images that demonstrates how variations in atmospheric moisture cause cumulous clouds to form and dissipate. The introduction explains how the clouds condense as moist air rises, and then evaporate as drier air moves in. Movie controls allow students to repeat, pause, or step through the animation, which can give students more time to analyze the images. Copyright 2005 Eisenhower National Clearinghouse

  6. Optical recording system based on a fiber optic image conduit: assessment of microscopic activation patterns in cardiac tissue.

    PubMed

    Rohr, S; Kucera, J P

    1998-08-01

    Optical recording of transmembrane voltage changes with the use of potentiometric dyes has opened the possibility of determining spatial patterns of electrical activity in excitable tissues. To follow such activation patterns on the cellular/subcellular level in heart cell cultures, a recording system was developed that features both high spatial resolution (4-200 microm) and high temporal resolution (uncertainty in the determination of delays between fast rising signals of +/-1 micros). Central to the system is a fiber optic image conduit consisting of 379 individual optical fibers. At one end the fibers are fused to form an input window that matches the size of the field of view of the microscope. At the other end, the fibers are loose, permitting a selectable subset to be connected to 80 discrete photodetectors. This design allows the sensitive area of the imager to be adapted to regions of interest in a given preparation, thus making optimal use of the limited number of detectors. Furthermore, by using a second fiber optic imager, individual photodetectors can be assigned to different optical ports, thus providing the means for fast and simultaneous dual-emission wavelength measurements. This feature permitted the elimination of motion artifacts arising from the myocytes without the use of contraction-suppressing drugs. PMID:9675208

  7. Optical recording system based on a fiber optic image conduit: assessment of microscopic activation patterns in cardiac tissue.

    PubMed Central

    Rohr, S; Kucera, J P

    1998-01-01

    Optical recording of transmembrane voltage changes with the use of potentiometric dyes has opened the possibility of determining spatial patterns of electrical activity in excitable tissues. To follow such activation patterns on the cellular/subcellular level in heart cell cultures, a recording system was developed that features both high spatial resolution (4-200 microm) and high temporal resolution (uncertainty in the determination of delays between fast rising signals of +/-1 micros). Central to the system is a fiber optic image conduit consisting of 379 individual optical fibers. At one end the fibers are fused to form an input window that matches the size of the field of view of the microscope. At the other end, the fibers are loose, permitting a selectable subset to be connected to 80 discrete photodetectors. This design allows the sensitive area of the imager to be adapted to regions of interest in a given preparation, thus making optimal use of the limited number of detectors. Furthermore, by using a second fiber optic imager, individual photodetectors can be assigned to different optical ports, thus providing the means for fast and simultaneous dual-emission wavelength measurements. This feature permitted the elimination of motion artifacts arising from the myocytes without the use of contraction-suppressing drugs. PMID:9675208

  8. Cloud frequency climatology at the Andes/Amazon transition: 2. Trends and variability

    NASA Astrophysics Data System (ADS)

    Halladay, Kate; Malhi, Yadvinder; New, Mark

    2012-12-01

    The climate and ecology of tropical montane systems is intimately connected with the complex spatial dynamics of cloud occurrence, but there have been few studies of the patterns and trends of cloud occurrence in tropical montane regions. We examine trends and variability in the cloud climatology of the Andes/Amazon transition in SW Amazonia using satellite data and ground-based observations. Results were compared for three zones within the study area: highlands (puna grassland), eastern slope (Tropical Montane Cloud Forest or TMCF) and lowlands. Time series of cloud frequency from ISCCP (International Satellite Cloud Climatology Project) were correlated with sea surface temperature (SST) anomalies from the HadISST data set for 5 regions including the tropical North Atlantic and the tropical Pacific. Detrended lowland cloud frequencies were significantly correlated with detrended tropical North Atlantic SSTs in the late dry season (August/September), whereas the eastern slope and the highlands were not significantly correlated with tropical North Atlantic SSTs. Pacific SST correlations were highest for eastern slope and highlands from March to May. Indian Ocean SST anomalies were significantly correlated with dry season cloud frequency for the lowlands and highlands. There are significant decreasing trends in cloud frequency on the lowlands in January, March and September and in March on the eastern slope. Trends in sunshine duration, 850 hPa zonal winds over the central Amazon, increases in diurnal temperature range, and comparisons with MODIS (Moderate Resolution Imaging Spectroradiometer) and observational data support the existence of these trends, and a link with the increasing trend in tropical North Atlantic SSTs. We suggest that continued increases in tropical North Atlantic SSTs will further reduce cloud frequency in the lowlands adjacent to the TMCF in the late dry season at least. In addition, a future increase in the occurrence of El Niño events would lead to decreased cloud frequency on the eastern slope and highlands.

  9. Searching Online Journals for Fluorescence Microscope Images Depicting Protein Subcellular Location Patterns

    Microsoft Academic Search

    Robert F. Murphy; Meel Velliste; Jie Yao; Gregory Porreca

    2001-01-01

    There is extensive interest in automating the collection, organization and analysis of biological data. Data in the form of images present special challenges for such efforts. Since fluorescence microscope images are a primary source of information about the location of proteins within cells, we have set as a long-term goal the building of a knowledge base system that can interpret

  10. Images of the Negro in American Literature. Patterns of Literary Criticism, No. 5.

    ERIC Educational Resources Information Center

    Gross, Seymour L. , Ed.; Hardy, John Edward, Ed.

    The 15 studies in this collection investigate the various images of the Negro in American literature--images which range from streotype to archetype. In the first six studies, critics discuss the literary tradition of the Negro in colonial literature (Milton Cantor), in the Southern novel prior to 1850 (Tremaine McDowell), in literature of the…

  11. Semi-automated 3D Leaf Reconstruction and Analysis of Trichome Patterning from Light Microscopic Images

    PubMed Central

    Schrader, Andrea; Hülskamp, Martin; Tresch, Achim

    2013-01-01

    Trichomes are leaf hairs that are formed by single cells on the leaf surface. They are known to be involved in pathogen resistance. Their patterning is considered to emerge from a field of initially equivalent cells through the action of a gene regulatory network involving trichome fate promoting and inhibiting factors. For a quantitative analysis of single and double mutants or the phenotypic variation of patterns in different ecotypes, it is imperative to statistically evaluate the pattern reliably on a large number of leaves. Here we present a method that enables the analysis of trichome patterns at early developmental leaf stages and the automatic analysis of various spatial parameters. We focus on the most challenging young leaf stages that require the analysis in three dimensions, as the leaves are typically not flat. Our software TrichEratops reconstructs 3D surface models from 2D stacks of conventional light-microscope pictures. It allows the GUI-based annotation of different stages of trichome development, which can be analyzed with respect to their spatial distribution to capture trichome patterning events. We show that 3D modeling removes biases of simpler 2D models and that novel trichome patterning features increase the sensitivity for inter-accession comparisons. PMID:23637587

  12. Get Your Head into the Clouds: Using Word Clouds for Analyzing Qualitative Assessment Data

    ERIC Educational Resources Information Center

    DePaolo, Concetta A.; Wilkinson, Kelly

    2014-01-01

    Word clouds (or tag clouds) are popular, fun ways to display text data in graphical form; however, we contend that they can also be useful tools in assessment. Using word clouds, instructors can quickly and easily produce graphical depictions of text representing student knowledge. By investigating the patterns of words or phrases, or lack…

  13. Clinical usefulness of narrow band imaging magnifying classification for colorectal tumors based on both surface pattern and microvessel features.

    PubMed

    Oka, Shiro; Tanaka, Shinji; Takata, Sayaka; Kanao, Hiroyuki; Chayama, Kazuaki

    2011-05-01

    We use the narrow band imaging (NBI) magnifying classification (Hiroshima Classification) on the basis of both their surface pattern and microvascular architecture to characterize colorectal tumors. Herein, we describe the Hiroshima Classification in detail and provide statistical data supporting its usefulness in diagnosing histologic type, whether a hyperplastic lesion, tubular adenoma, carcinoma with intramucosal to submucosal scanty invasion or carcinoma with submucosal massive invasion, and thus in selecting the appropriate treatment strategy. We also discuss the circumstances in which the Hiroshima Classification must be augmented by conventional pit pattern diagnosis. NBI magnification is easily carried out. We strongly recommend application of NBI magnification to the differential diagnosis of colorectal lesions as well as treatment decision making. PMID:21535213

  14. Characterization of healthy and osteoarthritic chondrocyte cell patterns on phase contrast CT images of the knee cartilage matrix

    NASA Astrophysics Data System (ADS)

    Nagarajan, Mahesh B.; Coan, Paola; Huber, Markus B.; Yang, Chien-Chun; Glaser, Christian; Reiser, Maximilian F.; Wismüller, Axel

    2012-03-01

    The current approach to evaluating cartilage degeneration at the knee joint requires visualization of the joint space on radiographic images where indirect cues such as joint space narrowing serve as markers for osteoarthritis. A recent novel approach to visualizing the knee cartilage matrix using phase contrast CT imaging (PCI-CT) was shown to allow direct examination of chondrocyte cell patterns and their subsequent correlation to osteoarthritis. This study aims to characterize chondrocyte cell patterns in the radial zone of the knee cartilage matrix in the presence and absence of osteoarthritic damage through both gray-level co-occurrence matrix (GLCM) derived texture features as well as Minkowski Functionals (MF). Thirteen GLCM and three MF texture features were extracted from 404 regions of interest (ROI) annotated on PCI images of healthy and osteoarthritic specimens of knee cartilage. These texture features were then used in a machine learning task to classify ROIs as healthy or osteoarthritic. A fuzzy k-nearest neighbor classifier was used and its performance was evaluated using the area under the ROC curve (AUC). The best classification performance was observed with the MF features 'perimeter' and 'Euler characteristic' and with GLCM correlation features (f3 and f13). With the experimental conditions used in this study, both Minkowski Functionals and GLCM achieved a high classification performance (AUC value of 0.97) in the task of distinguishing between health and osteoarthritic ROIs. These results show that such quantitative analysis of chondrocyte patterns in the knee cartilage matrix can distinguish between healthy and osteoarthritic tissue with high accuracy.

  15. The Spitzer Survey of the Small Magellanic Cloud: S3MC Imaging and Photometry in the Mid- and Far-Infrared Wavebands

    E-print Network

    Alberto D. Bolatto; Joshua D. Simon; Snezana Stanimirovic; Jacco Th. van Loon; Ronak Y. Shah; Kim Venn; Adam K. Leroy; Karin Sandstrom; James M. Jackson; Frank P. Israel; Aigen Li; Lister Staveley-Smith; Caroline Bot; Francois Boulanger; Monica Rubio

    2006-08-25

    We present the initial results from the Spitzer Survey of the Small Magellanic Cloud (S3MC), which imaged the star-forming body of the Small Magellanic Cloud (SMC) in all seven MIPS and IRAC wavebands. We find that the F_8/F_24 ratio (an estimate of PAH abundance) has large spatial variations and takes a wide range of values that are unrelated to metallicity but anticorrelated with 24 um brightness and F_24/F_70 ratio. This suggests that photodestruction is primarily responsible for the low abundance of PAHs observed in star-forming low-metallicity galaxies. We use the S3MC images to compile a photometric catalog of ~400,000 mid- and far-infrared point sources in the SMC. The sources detected at the longest wavelengths fall into four main categories: 1) bright 5.8 um sources with very faint optical counterparts and very red mid-infrared colors ([5.8]-[8.0]>1.2), which we identify as YSOs. 2) Bright mid-infrared sources with mildly red colors (0.16<[5.8]-[8.0]<0.6), identified as carbon stars. 3) Bright mid-infrared sources with neutral colors and bright optical counterparts, corresponding to oxygen-rich evolved stars. And, 4) unreddened early B stars (B3 to O9) with a large 24 um excess. This excess is reminiscent of debris disks, and is detected in only a small fraction of these stars (<5%). The majority of the brightest infrared point sources in the SMC fall into groups one to three. We use this photometric information to produce a catalog of 282 bright YSOs in the SMC with a very low level of contamination (~7%).

  16. Changes in speckle patterns induced by load application onto an optical fiber and its detection through image processing

    NASA Astrophysics Data System (ADS)

    Hasegawa, Makoto; Shimizu, Yuta; Nakamaru, Takuya

    2014-08-01

    Speckle patterns observed in an output light spot from an optical fiber are likely to be changed due to external disturbances applied to the fiber, and such changes can be utilized for sensing applications. In this paper, certain load was applied onto an optical fiber through which laser beams emitted from a laser diode were propagating, and changes in speckle patterns observed in the output light spot from the optical fiber were investigated as image data via a CCD camera. For the purpose of realizing effective load application onto an optical fiber, a load application section was employed in which several ridges were provided onto opposite flat plates. A jacket-covered communication-grade multi-mode glass optical fiber was placed in the load application section so that corrugated bending of the fiber was intentionally induced via load application due to the ridges. The obtained results from appropriate image processing showed that the number of speckles in the observed patterns decreased upon load application (up to 15kg) onto the optical fiber with satisfactory repeatability. The load was then reduced from the total of 15kg, and the number of speckles was found to recover. With different arrangements of the optical fiber in the load application section in which the number of load application points was altered, slight differences in the observed characteristics were recognized. Thus, there are possibilities of utilizing changes in speckle patterns observed in an output light spot from an optical fiber for sensing of load application onto the optical fiber by employing appropriate load application arrangements.

  17. Dark-field imaging based on post-processed electron backscatter diffraction patterns of bulk crystalline materials in a scanning electron microscope.

    PubMed

    Brodusch, Nicolas; Demers, Hendrix; Gauvin, Raynald

    2015-01-01

    Dark-field (DF) images were acquired in the scanning electron microscope with an offline procedure based on electron backscatter diffraction (EBSD) patterns (EBSPs). These EBSD-DF images were generated by selecting a particular reflection on the electron backscatter diffraction pattern and by reporting the intensity of one or several pixels around this point at each pixel of the EBSD-DF image. Unlike previous studies, the diffraction information of the sample is the basis of the final image contrast with a pixel scale resolution at the EBSP providing DF imaging in the scanning electron microscope. The offline facility of this technique permits the selection of any diffraction condition available in the diffraction pattern and displaying the corresponding image. The high number of diffraction-based images available allows a better monitoring of deformation structures compared to electron channeling contrast imaging (ECCI) which is generally limited to a few images of the same area. This technique was applied to steel and iron specimens and showed its high capability in describing more rigorously the deformation structures around micro-hardness indents. Due to the offline relation between the reference EBSP and the EBSD-DF images, this new technique will undoubtedly greatly improve our knowledge of deformation mechanism and help to improve our understanding of the ECCI contrast mechanisms. PMID:25461589

  18. VPI - VIBRATION PATTERN IMAGER: A CONTROL AND DATA ACQUISITION SYSTEM FOR SCANNING LASER VIBROMETERS

    NASA Technical Reports Server (NTRS)

    Rizzi, S. A.

    1994-01-01

    The Vibration Pattern Imager (VPI) system was designed to control and acquire data from laser vibrometer sensors. The PC computer based system uses a digital signal processing (DSP) board and an analog I/O board to control the sensor and to process the data. The VPI system was originally developed for use with the Ometron VPI Sensor (Ometron Limited, Kelvin House, Worsley Bridge Road, London, SE26 5BX, England), but can be readily adapted to any commercially available sensor which provides an analog output signal and requires analog inputs for control of mirror positioning. VPI's graphical user interface allows the operation of the program to be controlled interactively through keyboard and mouse-selected menu options. The main menu controls all functions for setup, data acquisition, display, file operations, and exiting the program. Two types of data may be acquired with the VPI system: single point or "full field". In the single point mode, time series data is sampled by the A/D converter on the I/O board at a user-defined rate for the selected number of samples. The position of the measuring point, adjusted by mirrors in the sensor, is controlled via a mouse input. In the "full field" mode, the measurement point is moved over a user-selected rectangular area with up to 256 positions in both x and y directions. The time series data is sampled by the A/D converter on the I/O board and converted to a root-mean-square (rms) value by the DSP board. The rms "full field" velocity distribution is then uploaded for display and storage. VPI is written in C language and Texas Instruments' TMS320C30 assembly language for IBM PC series and compatible computers running MS-DOS. The program requires 640K of RAM for execution, and a hard disk with 10Mb or more of disk space is recommended. The program also requires a mouse, a VGA graphics display, a Four Channel analog I/O board (Spectrum Signal Processing, Inc.; Westborough, MA), a break-out box and a Spirit-30 board (Sonitech International, Inc.; Wellesley, MA) which includes a TMS320C30 DSP processor, 256Kb zero wait state SRAM, and a daughter board with 8Mb one wait state DRAM. Please contact COSMIC for additional information on required hardware and software. In order to compile the provided VPI source code, a Microsoft C version 6.0 compiler, a Texas Instruments' TMS320C30 assembly language compiler, and the Spirit 30 run time libraries are required. A math co-processor is highly recommended. A sample MS-DOS executable is provided on the distribution medium. The standard distribution medium for this program is one 5.25 inch 360K MS-DOS format diskette. The contents of the diskettes are compressed using the PKWARE archiving tools. The utility to unarchive the files, PKUNZIP.EXE, is included. VPI was developed in 1991-1992.

  19. Discrete cloud structure on Neptune

    NASA Astrophysics Data System (ADS)

    Hammel, H. B.

    1989-07-01

    Recent CCD imaging data for the discrete cloud structure of Neptune shows that while cloud features at CH4-band wavelengths are manifest in the southern hemisphere, they have not been encountered in the northern hemisphere since 1986. A literature search has shown the reflected CH4-band light from the planet to have come from a single discrete feature at least twice in the last 10 years. Disk-integrated photometry derived from the imaging has demonstrated that a bright cloud feature was responsible for the observed 8900 A diurnal variation in 1986 and 1987.

  20. Computer-Aided Diagnosis of Splenic Enlargement Using Wave Pattern of Spleen in Abdominal CT Images: Initial Observations

    NASA Astrophysics Data System (ADS)

    Seong, Won; Cho, June-Sik; Noh, Seung-Moo; Park, Jong-Won

    In general, the spleen accompanied by abnormal abdomen is hypertrophied. However, if the spleen size is originally small, it is hard to detect the splenic enlargement due to abnormal abdomen by simply measure the size. On the contrary, the spleen size of a person having a normal abdomen may be large by nature. Therefore, measuring the size of spleen is not a reliable diagnostic measure of its enlargement or the abdomen abnormality. This paper proposes an automatic method to diagnose the splenic enlargement due to abnormality, by examining the boundary pattern of spleen in abdominal CT images.