Imagery

Distribution by Scientific Domains

Kinds of Imagery

  • guided imagery
  • landsat imagery
  • mental imagery
  • motor imagery
  • radar imagery
  • satellite imagery
  • visual imagery

  • Terms modified by Imagery

  • imagery techniques

  • Selected Abstracts


    GREAT BASIN IMAGERY IN NEWSPAPER COVERAGE OF YUCCA MOUNTAIN§

    GEOGRAPHICAL REVIEW, Issue 4 2005
    SOREN C. LARSEN
    ABSTRACT. Place imagery in printed news is a vital but overlooked feature of the public debate regarding the disposal of the nation's nuclear waste in the proposed Yucca Mountain repository northwest of Las Vegas, Nevada. A content analysis of newspaper coverage reveals that participants use Great Basin imagery in the rhetorical strategies involved in making arguments for and against the site. This article identifies specific elements in the news-production process that privilege certain conceptualizations of the Great Basin over others, and it highlights alternative visions that have appeared in editorials, travel pieces, and commentaries. Taken together, the data and analysis suggest that journalistic sensitivity to value-laden imagery can result in more balanced and critical news accounts of public debate. [source]


    DUTCH GENRE PAINTING AS RELIGIOUS ART: GABRIEL METSU'S ROMAN CATHOLIC IMAGERY

    ART HISTORY, Issue 2 2008
    VALERIE HEDQUIST
    Gabriel Metsu's reputation rests on his popular genre imagery; however, the Dutch artist also produced religious paintings with Roman Catholic symbolism. Archival documents, personal and professional relationships, and a small number of paintings confirm a close engagement with the Dutch Roman Catholic community from his youth in Leiden to his maturity in Amsterdam. Metsu's connections with Roman Catholic painters, poets, and priests in the Netherlands provided the cultural context for his religious art. Moreover, contemporary devotional publications and reproductive engravings after Italian art established iconographic and compositional solutions evident in Metsu's traditional religious scenes and in his genre imagery. [source]


    Gender and Agricultural Imagery: Pesticide Advertisements in the 21st Century Agricultural Transition

    CULTURE, AGRICULTURE, FOOD & ENVIRONMENT, Issue 1 2002
    Assistant Professor Margaret Kroma
    First page of article [source]


    Effector-independent representations of simple and complex imagined finger movements: a combined fMRI and TMS study

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003
    J. P. Kuhtz-Buschbeck
    Abstract Kinesthetic motor imagery and actual execution of movements share a common neural circuitry. Functional magnetic resonance imaging was used in 12 right-handed volunteers to study brain activity during motor imagery and execution of simple and complex unimanual finger movements of the dominant and the nondominant hand. In the simple task, a flexible object was rhythmically compressed between thumb, index and middle finger. The complex task was a sequential finger-to-thumb opposition movement. Premotor, posterior parietal and cerebellar regions were significantly more active during motor imagery of complex movements than during mental rehearsal of the simple task. In 10 of the subjects, we also used transcranial magnetic brain stimulation to examine corticospinal excitability during the same motor imagery tasks. Motor-evoked potentials increased significantly over values obtained in a reference condition (visual imagery) during imagery of the complex, but not of the simple movement. Imagery of finger movements of either hand activated left dorsal and ventral premotor areas and the supplementary motor cortex regardless of task complexity. The effector-independent activation of left premotor areas was particularly evident in the simple motor imagery task and suggests a left hemispherical dominance for kinesthetic movement representations in right-handed subjects. [source]


    Population Estimation Using Landsat Enhanced Thematic Mapper Imagery

    GEOGRAPHICAL ANALYSIS, Issue 1 2007
    Changshan Wu
    An assessment of two groups of approaches for estimating urban population with remote-sensing information is presented in this article. These approaches, zonal and pixel-based models, are applied to Landsat Enhanced Thematic Mapper images of a portion of Columbus, Ohio, to generate population estimates. The zonal approach uses impervious surface fraction, spectral radiance, and land-use/land-cover classification to derive population estimates. The pixel-based approach uses impervious surface fraction and spectral radiance to estimate the population of residential areas. To assess robustness, these models were applied to Dayton, Ohio. A comparative study indicates that the models generated promising results in estimating regional population counts. However, zonal regression with spectral radiance produced large errors (76%) for census block groups, whereas other models gave significantly better estimation accuracy. Comparing the performance of the indicators, impervious surface fraction is competitive, and slightly but consistently better than land-use classification. In comparison with traditional zonal approaches, pixel-based models give somewhat better estimation accuracy. [source]


    Narcissism and Cardiovascular Reactivity to Rejection Imagery,

    JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 5 2009
    Kristin L. Sommer
    This study examined the interactive effects of imagined rejection and narcissism on cardiovascular reactivity (CVR). Participants completed measures of overt narcissism (Narcissistic Personality Inventory, NPI; Raskin & Hall, 1979), overt,covert narcissism (Margolis & Thomas, 1980), and trait self-esteem. They then imagined 2 scenarios culminating in either interpersonal acceptance or rejection. Systolic (SBP) and diastolic blood pressure (DBP) and heart rate (HR) were assessed before, during, and after the imagery. Overt,covert narcissism was positively associated with task increases in SBP and DBP and recovery elevation of HR following rejection, but not acceptance. Similar effects on SBP were found for the Entitlement/Exploitativeness dimension of the NPI. Lower self-esteem predicted greater task increases in SBP, DBP, and HR across conditions. Implications for health are discussed. [source]


    Detection of Fecal Contamination on Cantaloupes Using Hyperspectral Fluorescence Imagery

    JOURNAL OF FOOD SCIENCE, Issue 8 2005
    Angela M. Vargas
    ABSTRACT To determine whether detection of fecal contamination on cantaloupes is possible using fluorescence imaging, hyperspectral images of cantaloupes artificially contaminated with a range of diluted bovine feces were acquired from 425 to 774 nm in responses to ultraviolet-A (320 to 400 nm) excitation. Evaluation of images at emission peak wavelengths indicated that 675 nm exhibited the greatest contrast between feces contaminated and untreated surface areas. Two-band ratios compared with the single-band images enhanced the contrast between the feces contaminated spots and untreated cantaloupe surfaces. The 595/655-nm, 655/520-nm, and 555/655-nm ratio images provided relatively high detection rates ranging from 79% to 96% across all feces dilutions. However, both single band and ratio methods showed a number of false positives caused by such features as scarred tissues on cantaloupes. Principal component analysis (PCA) was performed using the entire hyperspectral images data; 2nd and 5th principal component (PC) image exhibited differential responses between feces spots and false positives. The combined use of the 2 PC images demonstrated the detection of feces spots (for example, minimum level of 16-,g/mL dry fecal matter) with minimal false positives. Based on the PC weighing coefficients, the dominant wavelengths were 465, 487, 531, 607, 643, and 688 nm. This research demonstrated the potential of multispectral-based fluorescence imaging for online applications for detection of fecal contamination on cantaloupes. [source]


    The role of visual imagery in the enhanced cognitive interview: guided questioning techniques and individual differences,,

    JOURNAL OF INVESTIGATIVE PSYCHOLOGY AND OFFENDER PROFILING, Issue 1 2004
    Michael R. Davis
    Abstract The cognitive interview utilises mnemonics and other techniques to facilitate obtaining information from victims and witnesses. Research has indicated superior recall to standard police interviews. However, there has been minimal research regarding the role of individual differences. One area that has generated spirited theoretical debate is imagery ability, as guided imagery questioning is an important part of the enhanced cognitive interview. Imagery is also arguably an integral part of several mnemonics employed in the technique. The present study investigated the role of individual differences in imagery ability, as well as the effect of explicit instructions to image, on recall performance. Participants completed the Vividness of Visual Imagery Questionnaire (VVIQ), witnessed a film of a simulated crime, and were interviewed using the cognitive interview or a structured interview. While recall in the cognitive interview was superior, VVIQ scores had little relationship with recall of information. Further, recall elicited by guided imagery differed only minimally from that obtained using standard questioning in the structured interview. These results suggested that the relaxation and rapport building common to questioning in both interview conditions may evoke spontaneous imagery that is comparable to explicit instructions to image, regardless of individuals' inherent imagery ability. Future directions are discussed, including research focused on individual differences and a practical emphasis on context reinstatement and social facilitative techniques. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Monitoring Regional Riparian Forest Cover Change Using Stratified Sampling and Multiresolution Imagery,

    JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2010
    Peter R. Claggett
    Claggett, Peter R., Judy A. Okay, and Stephen V. Stehman, 2010. Monitoring Regional Riparian Forest Cover Change Using Stratified Sampling and Multiresolution Imagery. Journal of the American Water Resources Association (JAWRA) 46(2):334-343. DOI: 10.1111/j.1752-1688.2010.00424.x Abstract:, The Chesapeake Bay watershed encompasses 165,760 km2 of land area with 464,098 km of rivers and streams. As part of the Chesapeake Bay restoration effort, state and federal partners have committed to restoring 26,000 miles (41,843 km) of riparian forest buffers. Monitoring trends in riparian forest buffers over large areas is necessary to evaluate the efficacy of these restoration efforts. A sampling approach for estimating change in riparian forest cover from 1993/1994 to 2005 was developed and implemented in Anne Arundel County, Maryland, to exemplify a method that could be applied throughout the Bay watershed. All stream reaches in the county were stratified using forest cover change derived from Landsat imagery. A stratified random sample of 219 reaches was selected and forest cover change within the riparian buffer of each sampled reach was interpreted from high-resolution aerial photography. The estimated footprint of gross change in riparian forest cover (i.e., the sum of gross gain and gross loss) for the county was 1.83% (SE = 0.22%). Stratified sampling taking advantage of a priori knowledge of locations of change proved to be a practical and efficient protocol for estimating riparian forest buffer change at the county scale and the protocol would readily extend to much broader scale monitoring. [source]


    Visual Imagery: Visual Format or Visual Content?

    MIND & LANGUAGE, Issue 4 2010
    DOMINIC GREGORY
    It is clear that visual imagery is somehow significantly visual. Some theorists, like Kosslyn, claim that the visual nature of visualisations derives from features of the neural processes which underlie those episodes. Pylyshyn claims, however, that it may merely reflect special features of the contents which we grasp when we visualise things. This paper discusses and rejects Pylyshyn's own attempts to identify the respects in which the contents of visualisations are notably visual. It then offers a novel and very different account of what is distinctively sensory about the contents of sensory images. The paper's alternative account is used in explaining various pieces of phenomenological and behavioural data concerning visualisation. Finally, it is tentatively suggested that the proposed account of the contents of sensory images may also shed light upon some of the neurological data involving visualisation and sensory imagery more generally. [source]


    Access, Style and Imagery: The Audience for Prehistoric Rock Art in Atlantic Spain and Portugal, 4000,2000 BC

    OXFORD JOURNAL OF ARCHAEOLOGY, Issue 3 2002
    Richard Bradley
    The prehistoric rock art of western Iberia is normally divided into several styles with different associations, distributions and chronologies. Some are associated with monuments and others are found in the open air. A more basic division may help to account for the degree of overlap between these separate groups. This paper suggests that it may be possible to learn something of the significance of the painted and carved designs by considering their accessibility and the audiences to whom they could have been addressed. The argument is illustrated by recent fieldwork at Monte Penide and El Pedroso. [source]


    Block Design Performance in the Williams Syndrome Phenotype: A Problem with Mental Imagery?

    THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 6 2001
    Emily K. Farran
    Williams syndrome (WS) is a rare genetic disorder which, among other characteristics, has a distinctive cognitive profile. Nonverbal abilities are generally poor in relation to verbal abilities, but also show varying levels of ability in relation to each other. Performance on block construction tasks represents arguably the weakest nonverbal ability in WS. In this study we examined two requirements of block construction tasks in 21 individuals with WS and 21 typically developing (TD) control individuals. The Squares tasks, a novel twodimensional block construction task, manipulated patterns by segmentation and perceptual cohesiveness to investigate the first factor, processing preference (local or global), and by obliqueness to examine the second factor, the ability to use mental imagery. These two factors were investigated directly by the Children's Embeded Figures Test (CEFT; Witkin, Oltman, Raskin, & Karp, 1971) and a mental rotation task respectively. Results showed that individuals with WS did not differ from the TD group in their processing style. However, the ability to use mental imagery was significantly poorer in the WS group than the TD group. This suggests that weak performance on the block construction tasks in WS may relate to an inability to use mental imagery. [source]


    A Stitch in Time: Third-Wave Feminist Reclamation of Needled Imagery

    THE JOURNAL OF POPULAR CULTURE, Issue 4 2010
    RICIA A. CHANSKY
    First page of article [source]


    Virtual Cities From Digital Imagery

    THE PHOTOGRAMMETRIC RECORD, Issue 96 2000
    E. Gülch
    Increasing interest is being expressed in the use of virtual cities for many fields of application, ranging from planning and simulation to business, advertising and the games industry. Currently, the extraction of buildings from imagery is costly. However, recent developments in digital photogrammetry aim to produce more rapid and efficient methods of modelling three dimensional objects in urban environments. This paper presents a semi-automatic system for the extraction of buildings from digital aerial imagery with the aid of volumetric primitives. The user is supported by automated tools, for example matching tools, in order to reach the necessary efficiency. With an extraction time of about 20 s per building primitive, this method is competitive in terms of the performance of classical photogrammetric procedures, and also offers additional features for analysis, texture mapping and Internet applications. [source]


    The new object-spatial-verbal cognitive style model: Theory and measurement

    APPLIED COGNITIVE PSYCHOLOGY, Issue 5 2009
    Olesya Blazhenkova
    The current study challenges traditional approaches to Visual-Verbal cognitive style as a unitary bipolar dimension, and instead suggests a new three-dimensional cognitive style model developed on the basis of modern cognitive science theories that distinguish between object imagery, spatial imagery and verbal dimensions. The results of the confirmatory factor analysis demonstrated that the overall fit to the data of the new three-dimensional model of cognitive style was significantly better than that of a traditional model. Furthermore, based on the new theoretical model, we designed and validated a new self-report instrument assessing the individual differences in object imagery, spatial imagery and verbal cognitive styles, the Object-Spatial Imagery and Verbal Questionnaire (OSIVQ). Across a series of studies, the OSIVQ demonstrated acceptable internal reliability as well as construct, criterion and ecological validity. The current study supports the validity of an object-spatial-verbal cognitive style dimension and related measures when developed on the basis of modern cognitive science theories. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Presentation modality effects in studying passages.

    APPLIED COGNITIVE PSYCHOLOGY, Issue 3 2003
    Are mental images always effective?
    The present research has tested the different efficacy of imagery-based and verbally-based strategies in the study of three passages presented orally or in written form. The first passage was a description rich in easily imagined details. The second was an abstract passage, easy to verbalize, but not to imagine. The third was the spatial description of a pathway which could be both imagined and verbalized. Experiment 1 compared participants who were instructed in the use of Imagery or verbal Rehearsal while in Experiment 2 participants had high or low imagery ability. A facilitating effect of oral presentation for Imagery and high-imagery ability groups and of written presentation for Rehearsal and low imagery-ability groups were hypothesized. Data confirmed this facilitating effect and showed that it was more evident for the easier-to-imagine passages. Results are discussed in a selective interference and working memory framework. Future implications and practical suggestions are given. Copyright © 2003 John Wiley & Sons, Ltd. [source]


    Taxonomic identification of Amazonian tree crowns from aerial photography

    APPLIED VEGETATION SCIENCE, Issue 4 2010
    Carlos E. González-Orozco
    Abstract Question: To what extent can aerial photography be used for taxonomic identification of Amazonian tree crowns? Objective: To investigate whether a combination of dichotomous keys and a web-based interface is a suitable approach to identify tree crowns. Location: The fieldwork was conducted at Tiputini Biodiversity Station located in the Amazon, eastern Ecuador. Methods: High-resolution imagery was taken from an airplane flying at a low altitude (600 m) above the ground. Imagery of the observable upper layer of the tree crowns was used for the analysis. Dichotomous identification keys for different types of crowns were produced and tested. The identification keys were designed to be web-based interactive, using Google Earth as the main online platform. The taxa analysed were Iriartea, Astrocaryum, Inga, Parkia, Cecropia, Pourouma, Guarea, Otoba, Lauraceae and Pouteria. Results: This paper demonstrates that a combination of photo-imagery, dichotomous keys and a web-based interface can be useful for the taxonomic identification of Amazonian trees based on their crown characteristics. The keys tested with an overall identification accuracy of over 50% for five of the ten taxa with three of them showing accuracy greater than 70% (Iriartea, Astrocaryum and Cecropia). Conclusions: The application of dichotomous keys and a web-based interface provides a new methodological approach for taxonomic identification of various Amazonian tree crowns. Overall, the study showed that crowns with a medium-rough texture are less reliably identified than crowns with smoother or well-defined surfaces. [source]


    Soil erosion assessment using geomorphological remote sensing techniques: an example from southern Italy

    EARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2010
    Sergio Lo Curzio
    Abstract The aim of this study is to assess of the distribution and map the geomorphological effects of soil erosion at the basin scale identifying newly-formed erosional landsurfaces (NeFELs), by means of an integration of Landsat ETM 7+ remotely sensed data and field-surveyed geomorphological data. The study was performed on a 228·6,km2 -wide area, located in southern Italy. The study area was first characterized from a lithological, pedological, land-use and morpho-topographic point of view and thematic maps were created. Then, the georeferenced Landsat ETM 7+ satellite imagery was processed using the RSI ENVI 4.0 software. The processing consisted of contrast stretching, principal component analysis (PCA), decorrelation stretching and RGB false colour compositing. A field survey was conducted to characterize the features detected on the imagery. Particular attention was given to the NeFELs, which were located using a global positioning system (GPS). We then delimited the Regions of Interest (ROI) on the Landsat ETM 7+ imagery, i.e. polygons representing the ,ground-truth', discriminating the NeFELs from the other features occurring in the imagery. A simple statistical analysis was conducted on the digital number (DN) values of the pixels enclosed in the ROI of the NeFELs, with the aim to determine the spectral response pattern of such landsurfaces. The NeFELs were then classified in the entire image using a maximum likelihood classification algorithm. The results of the classification process were checked in the field. Finally, a spatial analysis was performed by converting the detected landsurfaces into vectorial format and importing them into the ESRI ArcViewGIS 9.0 software. Application of these procedures, together with the results of the field survey, highlighted that some ,objects' in the classified imagery, even if displaying the same spectral response of NeFELs, were not landsurfaces subject to intense soil erosion, thus confirming the strategic importance of the field-checking for the automatically produced data. During the production of the map of the NeFELs, which is the final result of the study, these ,objects' were eliminated by means of simple, geomorphologically-coherent intersection procedures in a geographic information system (GIS) environment. The overall surface of the NeFELs had an area of 22·9,km2, which was 10% of the total. The spatial analysis showed that the highest frequency of the NeFELs occurred on both south-facing and southwest-facing slopes, cut on clayey-marly deposits, on which fine-textured and carbonate-rich Inceptisols were present and displaying slope angle values ranging from 12° to 20°. The comparison of two satellite imageries of different periods highlighted that the NeFELs were most clearly evident immediately after summer tillage operations and not so evident before them, suggesting that these practices could have played an important role in inducing the erosional processes. Copyright © 2009 John Wiley & Sons, Ltd. [source]


    Remote sensing and GIS-based flood vulnerability assessment of human settlements: a case study of Gangetic West Bengal, India

    HYDROLOGICAL PROCESSES, Issue 18 2005
    Joy Sanyal
    Abstract Flooding due to excessive rainfall in a short period of time is a frequent hazard in the flood plains of monsoon Asia. In late September 2000, a devastating flood stuck Gangetic West Bengal, India. This particular event has been selected for this study. Instead of following the conventional approach of flooded area delineation and overall damage estimation, this paper seeks to identify the rural settlements that are vulnerable to floods of a given magnitude. Vulnerability of a rural settlement is perceived as a function of two factors: the presence of deep flood water in and around the settlement and its proximity to an elevated area for temporary shelter during an extreme hydrological event. Landsat ETM+ images acquired on 30 September 2000 have been used to identify the non-flooded areas within the flooded zone. Particular effort has been made to differentiate land from water under cloud shadow. ASTER digital elevation data have been used to assess accuracy and rectify the classified image. The presence of large numbers of trees around rural settlements made it particularly difficult to extract the flooded areas from their spectral signatures in the visible and infrared bands. ERS-1 synthetic aperture radar data are found particularly useful for extracting the settlement areas surrounded by trees. Finally, all information extracted from satellite imageries are imported into ArcGIS, and spatial analysis is carried out to identify the settlements vulnerable to river inundation. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    Land cover change and land degradation in parts of the southwest coast of Nigeria

    AFRICAN JOURNAL OF ECOLOGY, Issue 2009
    Mayowa Fasona
    Abstract Frequent alteration in land cover often leads to decreased stability of ecosystems which can also increase the vulnerability of rural communities to externalities of environmental change. This study carried out in parts of the coast of southwestern Nigeria utilized topographic base maps and two-time Landsat TM imageries to assess the trend in land cover changes and ecosystems degradation for the three time periods 1965, 1986 and 2001. Remote sensing, geographic information systems and landscape pattern analysis were employed for data processing and analysis. The focus of the analysis was on land cover change, land degradation, and changes in landscape pattern resulting from interplay of natural and anthropogenic drivers. The results show increased trend in human-induced land cover change with concomitant severe negative impacts on ecosystems and livelihoods. About 98,000ha (30% of the area) was seriously degraded as at 2001. About 33,000ha (10%) was under permanent saline water inundation with about 21 communities already dislocated. Loss of fragile ecosystems including marshland (from 7.7% in 1965 to 1% in 2001) and mangrove (from 14.6% in 1965 to 3.1% in 2001) was intense, while over 300 ponds/small lakes which are important for the local fishing economy have disappeared. About eighteen communities were also dislocated by erosion in a section around the southeastern parts of the coastline. Landscape metrics generated, suggested increased ecosystems perturbation and landscape fragmentation. The paper also discussed the implications of these rapid changes for ecosystems stability, food security and sustainable rural livelihoods in the area. [source]


    A conditional GIS-interpolation-based model for mapping soil-water erosion processes in Lebanon

    LAND DEGRADATION AND DEVELOPMENT, Issue 2 2008
    R. Bou Kheir
    Abstract Soil erosion by water is a major cause of landscape degradation in Mediterranean environments, including Lebanon. This paper proposes a conditional decision-rule interpolation-based model to predict the distribution of multiple erosion processes (i.e. sheet, mass and linear) in a representative area of Lebanon from the measured erosion signs in the field (root exposure, earth pillars, soil etching and drift and linear channels). First, erosion proxies were derived from the structural OASIS classification of Landsat thematic mapper (TM) imageries combined with the addition of several thematic erosion maps (slope gradient, aspect and curvature, drainage density, vegetal cover, soil infiltration and erodibility and rock infiltration/movement) under a geographic information systems (GIS) environment. Second, erosion signs were measured in the field, and interpolated by the statistical moments (means and variance) in the defined erosion proxies, thus producing quantitative erosion maps (t,ha,1) at a scale of 1:100,000. Seven decision rules were then generated and applied on these maps in order to produce the overall decisive erosion map reflecting all existing erosion processes, that is, equality (ER), dominance (DOR), bimodality (BR), masking (MR), aggravating (AR), dependence (DER) and independence (IR). The produced erosion maps are divided into seven classes ranging between 0 and more than 1·8,t,ha,1 for sheet erosion, and 0 and more than 10·5,t,ha,1 for mass and linear erosion. They are fairly matching with coincidences values equal to 43 per cent (sheet/linear), 48 per cent (sheet/mass) and 49 per cent (linear/mass). The overall accuracies of these maps were estimated to be 76 per cent (sheet erosion), 78 per cent (mass erosion) and 78·5 per cent (linear erosion). The overall decisive erosion map with 15 classes corresponds well to land management needs. The model used is relatively simple, and may also be applied to other areas. It is particularly useful when GIS database on factors influencing erosion is limited. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Interactive Visualization of Function Fields by Range-Space Segmentation

    COMPUTER GRAPHICS FORUM, Issue 3 2009
    John C. Anderson
    Abstract We present a dimension reduction and feature extraction method for the visualization and analysis of function field data. Function fields are a class of high-dimensional, multi-variate data in which data samples are one-dimensional scalar functions. Our approach focuses upon the creation of high-dimensional range-space segmentations, from which we can generate meaningful visualizations and extract separating surfaces between features. We demonstrate our approach on high-dimensional spectral imagery, and particulate pollution data from air quality simulations. [source]


    Interactive editing of digital fault models

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2010
    Jordan Van Aalsburg
    Abstract We describe an application to interactively create and manipulate digital fault maps, either by tracing existing (paper) fault maps created from geological surveys, or by directly observing fault expressions and earthquake hypocenters in remote sensing data such as high-resolution (,100k × 100k elevation postings) digital elevation models with draped color imagery. Such fault maps serve as input data to finite-element-method simulations of fault interactions, and are crucial to understand regional tectonic processes causing earthquakes, and have tentatively been used to forecast future seismic events or to predict the shaking from likely future earthquakes. This fault editor is designed for immersive virtual reality environments such as CAVEs, and presents users with visualizations of scanned 2D fault maps and textured 3D terrain models, and a set of 3D editing tools to create or manipulate faults. We close with a case study performed by one of our geologist co-authors (Yikilmaz), which evaluates the use of our fault editor in creating a detailed digital fault model of the North Anatolian Fault in Turkey, one of the largest, seismically active strike-slip faults in the world. Yikilmaz, who was directly involved in program development, used our fault editor both in a CAVE and on a desktop computer, and compares it to the industry-standard software package ArcGIS. Copyright © 2009 John Wiley & Sons, Ltd. [source]


    Parallel processing of remotely sensed hyperspectral imagery: full-pixel versus mixed-pixel classification

    CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2008
    Antonio J. Plaza
    Abstract The rapid development of space and computer technologies allows for the possibility to store huge amounts of remotely sensed image data, collected using airborne and satellite instruments. In particular, NASA is continuously gathering high-dimensional image data with Earth observing hyperspectral sensors such as the Jet Propulsion Laboratory's airborne visible,infrared imaging spectrometer (AVIRIS), which measures reflected radiation in hundreds of narrow spectral bands at different wavelength channels for the same area on the surface of the Earth. The development of fast techniques for transforming massive amounts of hyperspectral data into scientific understanding is critical for space-based Earth science and planetary exploration. Despite the growing interest in hyperspectral imaging research, only a few efforts have been devoted to the design of parallel implementations in the literature, and detailed comparisons of standardized parallel hyperspectral algorithms are currently unavailable. This paper compares several existing and new parallel processing techniques for pure and mixed-pixel classification in hyperspectral imagery. The distinction of pure versus mixed-pixel analysis is linked to the considered application domain, and results from the very rich spectral information available from hyperspectral instruments. In some cases, such information allows image analysts to overcome the constraints imposed by limited spatial resolution. In most cases, however, the spectral bands collected by hyperspectral instruments have high statistical correlation, and efficient parallel techniques are required to reduce the dimensionality of the data while retaining the spectral information that allows for the separation of the classes. In order to address this issue, this paper also develops a new parallel feature extraction algorithm that integrates the spatial and spectral information. The proposed technique is evaluated (from the viewpoint of both classification accuracy and parallel performance) and compared with other parallel techniques for dimensionality reduction and classification in the context of three representative application case studies: urban characterization, land-cover classification in agriculture, and mapping of geological features, using AVIRIS data sets with detailed ground-truth. Parallel performance is assessed using Thunderhead, a massively parallel Beowulf cluster at NASA's Goddard Space Flight Center. The detailed cross-validation of parallel algorithms conducted in this work may specifically help image analysts in selection of parallel algorithms for specific applications. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    Characteristics of Important Stopover Locations for Migrating Birds: Remote Sensing with Radar in the Great Lakes Basin

    CONSERVATION BIOLOGY, Issue 2 2009
    DAVID N. BONTER
    ave terrestre migratoria; migración; radar; sitios de escala temporal; WSR-88D Abstract:,A preliminary stage in developing comprehensive conservation plans involves identifying areas used by the organisms of interest. The areas used by migratory land birds during temporal breaks in migration (stopover periods) have received relatively little research and conservation attention. Methodologies for identifying stopover sites across large geographic areas have been, until recently, unavailable. Advances in weather-radar technology now allow for evaluation of bird migration patterns at large spatial scales. We analyzed radar data (WSR-88D) recorded during spring migration in 2000 and 2001 at 6 sites in the Great Lakes basin (U.S.A.). Our goal was to link areas of high migrant activity with the land-cover types and landscape contexts corresponding to those areas. To characterize the landscapes surrounding stopover locations, we integrated radar and land-cover data within a geographic information system. We compared landscape metrics within 5 km of areas that consistently hosted large numbers of migrants with landscapes surrounding randomly selected areas that were used by relatively few birds during migration. Concentration areas were characterized by 1.2 times more forest cover and 9.3 times more water cover than areas with little migrant activity. We detected a strong negative relationship between activity of migratory birds and agricultural land uses. Examination of individual migration events confirmed the importance of fragments of forested habitat in highly altered landscapes and highlighted large concentrations of birds departing from near-shore terrestrial areas in the Great Lakes basin. We conclude that conservation efforts can be more effectively targeted through intensive analysis of radar imagery. Resumen:,Una etapa preliminar en el desarrollo de planes de conservación integrales implica la identificación de áreas utilizadas por los organismos de interés. Las áreas utilizadas por aves terrestres migratorias durante escalas temporales en la migración (períodos de parada) han recibido relativamente poca atención de investigación y conservación. Hasta hace poco, las metodologías para la identificación de sitios de parada en áreas geográficas extensas han sido escasas. Ahora, los avances en la tecnología de radar meteorológico permiten la evaluación de patrones de migración de aves en escalas espaciales grandes. Analizamos datos de radar (WSR-88D) registrados en seis sitios en la cuenca de los Grandes Lagos (E.U.A.) durante la migración en las primaveras de 2000 y 2001. Nuestra meta fue relacionar áreas con gran actividad migratoria con los tipos de cobertura de suelo y los contextos del paisaje correspondientes a esas áreas. Para caracterizar los paisajes circundantes a las localidades de parada, integramos los datos de radar y de cobertura de suelo a un sistema de información geográfica. Comparamos las medidas del paisaje en un radio de 5 km en las áreas que consistentemente albergaron a grandes números de migrantes con los paisajes circundantes a áreas seleccionadas aleatoriamente y que eran utilizadas por relativamente pocas aves durante la migración. Las áreas de concentración se caracterizaron por tener 1.3 veces más cobertura forestal y 9.3 veces más cobertura de agua que las áreas con poca actividad migratoria. Detectamos una fuerte relación negativa entre la actividad de las aves migratorias y los usos de suelo agrícolas. El examen de eventos migratorios individuales confirmó la importancia de los fragmentos de hábitat boscoso en paisajes muy alterados y resaltó las grandes concentraciones de aves partiendo de áreas terrestres cercanas a la costa en la cuenca de los Grandes Lagos. Concluimos que los esfuerzos de conservación pueden ser abordados más efectivamente mediante el análisis intensivo de imágenes de radar. [source]


    Refining Biodiversity Conservation Priorities

    CONSERVATION BIOLOGY, Issue 6 2005
    GRANT M. HARRIS
    Bosque del Atlántico; percepción remota; priorización; SIG; sitios prioritarios para la conservación Abstract:,Although there is widespread agreement about conservation priorities at large scales (i.e., biodiversity hotspots), their boundaries remain too coarse for setting practical conservation goals. Refining hotspot conservation means identifying specific locations (individual habitat patches) of realistic size and scale for managers to protect and politicians to support. Because hotspots have lost most of their original habitat, species endemic to them rely on what remains. The issue now becomes identifying where this habitat is and these species are. We accomplished this by using straightforward remote sensing and GIS techniques, identifying specific locations in Brazil's Atlantic Forest hotspot important for bird conservation. Our method requires a regional map of current forest cover, so we explored six popular products for mapping and quantifying forest: MODIS continuous fields and a MODIS land cover (preclassified products), AVHRR, SPOT VGT, MODIS (satellite images), and a GeoCover Landsat thematic mapper mosaic (jpg). We compared subsets of these forest covers against a forest map based on a Landsat enhanced thematic mapper. The SPOT VGT forest cover predicted forest area and location well, so we combined it with elevation data to refine coarse distribution maps for forest endemic birds. Stacking these species distribution maps enabled identification of the subregion richest in threatened birds,the lowland forests of Rio de Janeiro State. We highlighted eight priority fragments, focusing on one with finer resolved imagery for detailed study. This method allows prioritization of areas for conservation from a region >1 million km2 to forest fragments of tens of square kilometers. To set priorities for biodiversity conservation, coarse biological information is sufficient. Hence, our method is attractive for tropical and biologically rich locations, where species location information is sparse. Resumen:,Aunque hay acuerdo generalizado sobre las prioridades de conservación a escalas mayores (i. e., sitios prioritarios para la conservación de la biodiversidad), los límites son muy gruesos como para definir metas de conservación prácticas. La refinación de la conservación de sitios prioritarios significa la identificación de localidades específicas (parches de hábitat individuales) de tamaño y escala realistas para ser protegidos por gestores y apoyados por políticos. Debido a que los sitios prioritarios han perdido la mayor parte de su hábitat original, las especies endémicas dependen del que permanece. Ahora el asunto es identificar donde están el hábitat y las especies. Logramos lo anterior mediante técnicas directas de percepción remota y de SIG para identificar localidades específicas importantes para la conservación de aves en el sitio prioritario Bosque del Atlántico en Brasil. Nuestro método requiere de un mapa regional de la cobertura forestal actual, así que exploramos seis productos populares para el mapeo y cuantificación de bosques: campos continuos MODIS y una cobertura de suelo MODIS (productos preclasificados), AVHRR, SPOT VGT, MODIS (imágenes de satélite) y un mosaico GeoCover Landsat thematic mapper (jpg). Comparamos subconjuntos de estas coberturas forestales con las de un mapa basado en un Landsat enhanced thematic mapper. La cobertura forestal SPOT VGT predijo bien la superficie y localización del bosque, así que lo combinamos con datos de altitud para refinar los mapas generales de distribución de aves endémicas de bosques. La sobreposición de estos mapas de distribución permitió la identificación de la subregión más rica en aves amenazadas,los bosques en bajíos del Estado de Río de Janeiro. Dimos relevancia a ocho fragmentos prioritarios, con atención en uno con imágenes de resolución fina para estudio en detalle. Este método permite la priorización de áreas para conservación de fragmentos de decenas de kilómetros cuadrados en una región >1 millón km2. La información biológica general es suficiente para definir prioridades de conservación de la biodiversidad. Por lo tanto, nuestro método es atractivo para localidades tropicales y biológicamente ricas, para las que la información sobre la ocalización de las especies es escasa. [source]


    Possible Environmental Factors Underlying Amphibian Decline in Eastern Puerto Rico: Analysis of U.S. Government Data Archives

    CONSERVATION BIOLOGY, Issue 4 2001
    Robert F. Stallard
    I examined changes in environmental conditions by examining time-series data sets that extend back at least into the 1980s, a period when frog populations were declining. The data include forest cover; annual mean, minimum, and maximum daily temperature; annual rainfall; rain and stream chemistry; and atmospheric-dust transport. I examined satellite imagery and air-chemistry samples from a single National Aeronautics and Space Administration aircraft flight across the Caribbean showing patches of pollutants, described as thin sheets or lenses, in the lower troposphere. The main source of these pollutants appeared to be fires from land clearing and deforestation, primarily in Africa. Some pollutant concentrations were high and, in the case of ozone, approached health limits set for urban air. Urban pollution impinging on Puerto Rico, dust generation from Africa ( potential soil pathogens), and tropical forest burning ( gaseous pollutants) have all increased during the last three decades, overlapping the timing of amphibian declines in eastern Puerto Rico. None of the data sets pointed directly to changes so extreme that they might be considered a direct lethal cause of amphibian declines in Puerto Rico. More experimental research is required to link any of these environmental factors to this problem. Resumen: Las pasadas tres décadas han visto grandes disminuciones poblacionales de especies de anfibios en altas elevaciones de Puerto Rico oriental, una región única en los trópicos húmedos debido al grado de monitoreo ambiental que se ha llevado a cabo mediante los esfuerzos de las agencias de gobierno de los Estados Unidos. Examiné los cambios en condiciones ambientales mediante el análisis de datos de series de tiempo que se extienden hasta los 1980s, un periodo en el que las poblaciones de ranas estaban declinando. Los datos incluyen cobertura forestal; temperatura diaria media, mínima y máxima anual; precipitación anual; química de la lluvia y arroyos; y el transporte atmosférico de polvo. Examiné imágenes de satélite y muestras de química del aire obtenidos de un solo vuelo de una nave de la NASA a lo largo del Caribe que mostraba parches de contaminantes descritas como capas delgadas de lentes en la inferior troposfera. La mayor fuente de contaminantes parece ser los incendios de tierras clareadas y la deforestación, principalmente en África. Algunas concentraciones de contaminantes fueron altas y en el caso del ozono, se aproximó a los límites de salud establecidos para aire urbano. La contaminación urbana afectando a Puerto Rico, la generación de polvo en África ( patógenos del suelo potenciales) y la quema de bosque tropical (contaminantes gaseosos) han incrementado durante las últimas tres décadas, superponiéndose con el periodo en que oturrieron las disminuciones de anfibios en Puerto Rico oriental. Ninguno de estos conjuntos de datos señaló directamente hacia cambios tan extremos que debieran ser considerados como una causa letal directa de las disminuciones en Puerto Rico. Se requiere de más investigación experimental que vincule a estos factores ambientales con este problema. [source]


    The emptiness of zero: representations of loss, absence, anxiety and desire in the late twentieth century

    CRITICAL QUARTERLY, Issue 1 2004
    Kathy Smith
    As the new millenium approached, the anxiety which this moment generated found resonance in various cultural representations, and the appearance of spectral imagery seemed to indicate an anxiety about subjectivity, and about its fragmentation or complete loss. Unable to comtemplate a state beyond this loss, there came into being a crisis in subjectivity itself, and the existence of the destabilized millenium subject. This subject approached the moment by both fixating on the threshold and by disavowing what lay beyond. These strategies, and the underlying anxiety which brought them into existence, were resonated through many of the cultural representations of the time. This paper argues that it is through nachträglichkeit - a 'making sense' in retrospect of earlier disparate experiences - that we can begin to examine, contextualise and account for the phenomenon of 'millenium frenzy' which came about at the end of 1999. It constructs a reading of this moment, and of two particular filmic representations which resonate the concerns of the time, examining in the process how - from a psychoanalytic perspective - culture might be understood through its representations, and how these representations can be understood through culture. [source]


    The Animated Muse: An Interpretive Program for Creative Viewing

    CURATOR THE MUSEUM JOURNAL, Issue 3 2005
    Austin Clarkson
    ABSTRACT Explore a Painting in Depth, an experiment presented in the Canadian Collection of the Art Gallery of Ontario, consisted of a booth that offered seating for two visitors and, opposite them, The Beaver Dam, a 1919 landscape painting by the Canadian artist J. E. H. MacDonald. In a 12-minute audio-guided Exercise for Exploring, visitors were invited to engage in a creative process with the imagery of the painting. This paper sketches how the experiment evolved, presents the background of the Exercise for Exploring, and surveys the effects of the exhibit on a wide range of visitors. The question is raised: How can facilitating visitors' creative responses to artworks be part of the museum's educational mandate and its arsenal of interpretive resources? More broadly: Do strategies that foster and privilege visitor creativity, as well as honor the creativity of artists, affect the accessibility and relevance of the museum for the general public? [source]


    Script-driven imagery of self-injurious behavior in patients with borderline personality disorder: a pilot FMRI study

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2010
    A. Kraus
    Objective:, Self-injurious behavior (SIB) is one of the most distinctive features of borderline personality disorder (BPD) and related to impulsivity and emotional dysregulation. Method:, Female patients with BPD (n = 11) and healthy controls (n = 10) underwent functional magnetic resonance imaging while listening to a standardized script describing an act of self-injury. Experimental sections of the script were contrasted to the neutral baseline section and group-specific brain activities were compared. Results:, While imagining the reactions to a situation triggering SIB, patients with BPD showed significantly less activation in the orbitofrontal cortex compared with controls. Furthermore, only patients with BPD showed increased activity in the dorsolateral prefrontal cortex during this section and a decrease in the mid-cingulate while imagining the self-injurious act itself. Conclusion:, This pattern of activation preliminary suggests an association with diminished emotion regulation, impulse control as well as with response selection and reappraisal during the imagination of SIB. [source]