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Awareness of memory loss was rated in 57 patients with clinically diagnosed Alzheimer's disease, and analyzed in relation to neuropsychological tests and presence of depression. Single photon emission computed tomography measures of regional cerebral blood flow were obtained on an unselected subsample of 20. Anosognosia was associated with diminished(More)
Advances in aerial platforms, imaging sensors, image processing/computing, geo-positioning systems, and wireless communications make near real-time change detection more practical and cost effective. In Coulter et al. (2003) and Stow et al. (2003), we documented a method for collecting and precisely co-registering multitemporal airborne frame imagery that(More)
Little research has been conducted on how differing spatial resolutions or classification techniques affect image-driven identification and categorization of slum neighborhoods in developing nations. This study assesses the correlation between satellite-derived land cover and census-derived socioeconomic variables in Accra, Ghana to determine whether the(More)
West Africa has a rapidly growing population, an increasing fraction of which lives in urban informal settlements characterized by inadequate infrastructure and relatively high health risks. Little is known, however, about the spatial or health characteristics of cities in this region or about the spatial inequalities in health within them. In this article(More)
Large format digital camera (LFDC) systems are becoming more broadly available and regularly collect image data over large areas. Spectral and radiometric attributes of imagery from LFDC systems make this type of image data appropriate for semi-automated change detection. However, achieving accurate spatial co-registration between multitemporal image sets(More)
—Accurate spatial registration between multitemporal imagery is necessary if pixel-level changes are to be detected. Registration of multitemporal airborne frame imagery is complicated by image distortions resulting from wide view angles and variable terrain. A novel technique for acquiring and precisely registering multitemporal airborne frame imagery is(More)
A study to determine whether root rot infestations can be detected using high spatial resolution digital multispectral video (DMSV) data was conducted in the Imperial Valley of California. DMSV data were collected on two dates over 25 fields during the summer of 1999 using a light aircraft. The DMSV images included four spectral bands centered on 530 nm,(More)
The objectives are to (1) quantify, map, and analyze vegetation cover distributions and changes across Accra, Ghana, for 2002 and 2010; and (2) examine the statistical relationship between vegetation cover and a housing quality index (HQI) for 2000 at the neighborhood level. Pixel-level vegetation cover maps derived using threshold classification of 2002(More)
The effect of using spectral transform images as input data on segmentation quality and its potential effect on products generated by object-based image analysis are explored in the context of land cover classification in Accra, Ghana. Five image data transformations are compared to untransformed spectral bands in terms of their effect on segmentation(More)
— A novel and patent pending approach representing a new paradigm for persistent wide area surveillance is presented. (SDSU) researchers have developed a method for accurate and automated detection of people and vehicles moving through remote border regions or other uninhabited areas. Instead of imaging small areas at video frame rates (as with traditional(More)