Institute for Systems Research Technical Reports

Permanent URI for this collectionhttp://hdl.handle.net/1903/4376

This archive contains a collection of reports generated by the faculty and students of the Institute for Systems Research (ISR), a permanent, interdisciplinary research unit in the A. James Clark School of Engineering at the University of Maryland. ISR-based projects are conducted through partnerships with industry and government, bringing together faculty and students from multiple academic departments and colleges across the university.

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Author: search.filters.author.Berenstein, Carlos A.Subject: search.filters.subject.Intelligent Servomechanisms

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Now showing 1 - 7 of 7
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    The Inverse Conductivity Problem and the Hyperbolic X-Ray Transform
    (1993) Berenstein, Carlos A.; Tarabusi, E. Casadio; ISR
    It is shown here how the approximate inversion algorithm of Barber & Brown for the linearized inverse conductivity problem in the disk can be interpreted exactly in terms of the X-ray transform with respect to the Poincare metric and of suitable convolution operators.
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    Local Inversion of the Radon Transform in Even Dimensions Using Wavelets
    (1993) Berenstein, Carlos A.; Walnut, D.; ISR
    We use the theory of the continuous wavelet transform to derive inversion formulas for the Radon transform. These formulas are almost local for even dimensions in the sense that for a given mean square error we can decide which lines near a point must be used to approximate the function at the point within the given error.
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    Wronskians and Linear Dependency of Entire Functions in Cn
    (1992) Berenstein, Carlos A.; Chang, Der-Chen; Li, Bao Q.; ISR
    Wronskians criteria for linear dependency of multivariate functions are given
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    Interpolating Varieties for Spaces of Meromorphic Functions
    (1992) Berenstein, Carlos A.; Li, Bao Q.; ISR
    Various interesting results on interpolation theory of entire functions with given growth conditions have been obtained by imposing conditions on multiplicity varieties and weights. All the results discussed in the literature are limited to the space of entire functions. In this paper, we shall extend and generalize the interpolation problem of entire functions to meromorphic functions. The analytic conditions sufficient and necessary for a given multiplicity variety to be interpolating for meromorphic functions with given growth conditions will be obtained. Moreover, purely geometric characterization of interpolating varieties will be given for slowly decreasing radial weights which enable us to determine whether or not a given multiplicity variety is an interpolating variety by direct calculation. when weights grow so rapidly as to allow infinite order functions in the considered space, the geometric conditions would become more delicate. For such weights p(z), we also find purely geometric sufficient as well as necessary conditions provided that log p(exp r) is convex. As corollaries of our results, one obtains the corresponding results for the interpolation of entire functions.
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    Computer Assisted Tomography Applied to Plasma Electron Distribution Functions
    (1992) Li, S.; Lin, Qipeng; Coplan, M.A.; Moore, J.H.; Berenstein, Carlos A.; ISR
    We consider several possible instruments based on Computer Tomography to determine space plasma distribution functions.
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    Range of the k-Dimensional Radon Transform in Real Hyperbolic Spaces
    (1991) Berenstein, Carlos A.; Tarabusi, E.C.; ISR
    Characterizations of the range of the totally geodesic k- dimensional Radon transform on the n-dimensional hyperbolic space are given both in terms of moment conditions and as the kernel of a differential operator.
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    Bounds for the Degrees in Polynomial Equations
    (1990) Berenstein, Carlos A.; Yger, A.; ISR
    Conference delivered by Dr. C.A. Berenstein at the American Mathematics Society Summer Institute in Several Complex Variables, Santa Cruz, August 1989.