A. C. Nelson

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The reconstruction of planar and three-dimensional current distributions from measured biomagnetic signals is a new field of research, known as biomagnetic computed tomography. This noninvasive imaging technique promises to provide precise, millimeter-sized resolution images of the electrical currents in tissues or organs. We performed simulation studies on(More)
The National Research Council recently issued the report Driving and the Built Environment: The Effect of Compact Development on Motorized Travel, Energy Use, and CO 2 Emissions. This report is well-researched and well-written. This is not surprising since the NRC committee that produced the report—the Committee for the Study on the Relationships Among(More)
* Copies of these and other Urban Center publications are available on the web site, www.brookings.edu/urban, or by calling the Urban Center at (202) 797-6139. Foundation for their support of our work on metropolitan trends. The Center's Metropolitan Initiative aims to better understand the mix of market, demographic and policy trends that contribute to the(More)
An optical tomography system is developed for generating three-dimensional reconstructions of thick objects from projections. The system is useful for studying transparent structures that are 1-10 mm in diameter. Evaluation of the reconstruction system with a test object demonstrates 98% geometric accuracy, 90% accuracy in the detection of boundaries, and(More)
Resolution of biomagnetic images using the technique of the alternating projections is proposed. Our image reconstruction procedure is divided in two steps. First, the biomagnetic inverse problem is solved by use of the projection theorem to reconstruct an initial image of the current distribution from a given magnetic field profile. Although the current(More)