SRI International

About: SRI International is a nonprofit organization based out in Menlo Park, California, United States. It is known for research contribution in the topics: Ionosphere & Laser. The organization has 7222 authors who have published 13102 publications receiving 660724 citations. The organization is also known as: Stanford Research Institute & SRI.

Multimodal user interfaces in the Open Agent Architecture

Abstract: The design and development of the Open Agent Architecture (OAA) 1 system has focused on providing access to agentbased applications through an intelligent, cooperative, distributed, and multimodal agent-based user interfaces. The current multimodal interface supports a mix of spoken language, handwriting and gesture, and is adaptable to the user’ s preferences, resources and environment. Only the primary user interface agents need run on the local computer, thereby simplifying the task of using a range of applications from a variety of platforms, especially low-powered computers such as Personal Digital Assistants (PDAs). An important consideration in the design of the OAA was to facilitate mix-andmatch: to facilitate the reuse of agents in new and unanticipated applications, and to support rapid prototyping by facilitating the replacement of agents by better versions. The utility of the agents and tools developed as part of this ongoing research project has been demonstrated by their use as infrastructure in unrelated projects.

Computer Description of Curved Objects

Abstract: A ranging system, consisting of a laser, computer-controlled optical deflection assembly, and TV camera, obtains three-dimensional images of curved solid objects. The object is segmented into parts by grouping parallel traces obtained from the ranging system. Making use of the property of generalized translational invariance, the parts are described in terms of generalized cylinders, consisting of a space curve, or axis, and a circular cross section function on this axis.

Increased brain white matter diffusivity in normal adult aging: relationship to anisotropy and partial voluming.

Abstract: Diffusion tensor imaging (DTI) was used to examine 1) age-related changes in genu, splenium, and centrum semiovale white matter diffusivity in 64 healthy men and women (age 23–85 years); 2) the relationship between diffusivity (trace) and fractional anisotropy (FA) across and within individuals; and 3) the role of macrostructural and microstructural partial voluming effects on the DTI metrics. Regional differences were greater in FA (∼43%) than in trace (∼16%). Depending on the region of interest, trace increased with age (r = 0.24 to 0.58) and FA decreased with age (r = −0.29 to −0.79). FA was inversely correlated with trace, even when controlling for age. Histogram analysis of trace and FA following systematic expansion and dilation of the white matter regions demonstrated greater susceptibility of FA than trace to error arising from macrostructural partial voluming, i.e., erroneous inclusion of primarily nonwhite-matter voxels. Three-phase ellipsoid shape analysis revealed that after morphometric erosion the spherical component remained greater in older than younger subjects in the splenium and centrum, suggesting that age-related reduction in FA arises from intravoxel increased interstitial fluid. Reducing the size of the white matter samples to control for macrostructural partial voluming attenuated but did not negate effects, indicating that observed changes in white matter with aging can reflect real microstructural alterations rather than sampling artifact. Morphological dilation of white matter regions of interest resulting in purposeful inclusion of non-white matter pixels significantly reduced mean FA, suggesting that reports of FA values below 0.25 in healthy adults may reflect partial voluming rather than actual changes in white matter coherence. Magn Reson Med 49:953–961, 2003. © 2003 Wiley-Liss, Inc.

Technology and Classroom Practices

Abstract: This study examines the findings from 174 case studies of innovative pedagogical practices using technology from 28 participating countries. The study looks at how classrooms world-wide are using technology to change the practices of teachers and students. Within many of these classrooms, the use of technological tools and resources supports students as they search for information, design products, and publish results. Teachers create structure, provide advice, and monitor progress. Beyond these commonly exhibited practices, the study identifies specific patterns of classroom practice that are more likely to be associated with reports of certain desirable student outcomes. Examples are provided.