1,119 research outputs found

    Video signal processing system uses gated current mode switches to perform high speed multiplication and digital-to-analog conversion

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    Video signal processor uses special-purpose integrated circuits with nonsaturating current mode switching to accept texture and color information from a digital computer in a visual spaceflight simulator and to combine these, for display on color CRT with analog information concerning fading

    Local RBF approximation for scattered data fitting with bivariate splines

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    In this paper we continue our earlier research [4] aimed at developing effcient methods of local approximation suitable for the first stage of a spline based two-stage scattered data fitting algorithm. As an improvement to the pure polynomial local approximation method used in [5], a hybrid polynomial/radial basis scheme was considered in [4], where the local knot locations for the RBF terms were selected using a greedy knot insertion algorithm. In this paper standard radial local approximations based on interpolation or least squares are considered and a faster procedure is used for knot selection, signicantly reducing the computational cost of the method. Error analysis of the method and numerical results illustrating its performance are given

    Proton Wires in an Electric Field: the Impact of Grotthuss Mechanism on Charge Translocation

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    We present the results of the modeling of proton translocation in finite H-bonded chains in the framework of two-stage proton transport model. We explore the influence of reorientation motion of protons, as well as the effect of electric field and proton correlations on system dynamics. An increase of the reorientation energy results in the transition of proton charge from the surrounding to the inner water molecules in the chain. Proton migration along the chain in an external electric field has a step-like character, proceeding with the occurrence of electric field threshold-type effects and drastic redistribution of proton charge. Electric field applied to correlated chains induces first a formation of ordered dipole structures for lower field strength, and than, with a further field strength increase, a stabilization of states with Bjerrum D-defects. We analyze the main factors responsible for the formation/annihilation of Bjerrum defects showing the strong influence of the complex interplay between reorientation energy, electric field and temperature in the dynamics of proton wire.Comment: 28 pages, 9 figure

    Cosmological Perturbations of Quantum-Mechanical Origin and Anisotropy of the Microwave Background

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    Cosmological perturbations generated quantum-mechanically (as a particular case, during inflation) possess statistical properties of squeezed quantum states. The power spectra of the perturbations are modulated and the angular distribution of the produced temperature fluctuations of the CMBR is quite specific. An exact formula is derived for the angular correlation function of the temperature fluctuations caused by squeezed gravitational waves. The predicted angular pattern can, in principle, be revealed by the COBE-type observations.Comment: 9 pages, WUGRAV-92-17 Accepted for Publication in Phys. Rev. Letters (1993

    Epidemiological Study of Learning Disabled Adolescents in Secondary Schools: Details of the Methodology

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    This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities.Research results presented in Research Reports 12 through 20 detail findings from this comprehensive epidemiology study conducted during 1979-80 by the Institute. It is important for the reader to study and view each of these individual reports in relation to this overall line of research. An understanding of the complex nature of the learning disability condition only begins to emerge when each specific topic or finding is seen as a partial, but important, piece of a larger whole

    An Epidemiological Study of Learning Disabled Adolescents in Secondary Schools: Classification and Discrimination of Learning Disabled and Low-Achieving Adolescents

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    This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities.In recent years, professionals in the field of learning disabilities have begun to address the impact of learning disabilities on adolescents and young adults. Although substantial attention has been directed to the manifestations of learning disabilities in elementary school age populations, the significantly different and increasingly complex demands on adolescents both in and out of school necessitate the development of systematic research on this population. The University of Kansas Institute for Research in Learning Disabilities has collected a broad array of data to form an epidemiological data base on LD adolescents and young adults. Data have been collected from learning disabled, low-achieving, and normal-achieving adolescents as well as from their parents and teachers. In addition, information from the environmental setting of the LD adolescents which pertains to interventions applied on behalf of the student, relationships with others, conditions under which he/she operates and support systems available for his/her use has also been collected. These data have been considered in relation to data on specific learner characterisecs to gain a more complete profile of the older LD individual. Research results presented in Research Reports 12 through 20 detail findings from this comprehensive epidemiology study conducted during 1979-80 by the Institute. It is important for the reader to study and view each of these individual reports in relation to this overall line of research. An understanding of the complex nature of the learning disability condition only begins to emerge when each specific topic or finding is seen as a partial, but important, piece of a larger whole

    An Epidemiological Study of Learning Disabled Adolescents in Secondary Schools: Health and Medical Aspects

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    This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities.Research results presented in Research Reports 12 through 20 detail findings from this comprehensive epidemiology study conducted during 1979-80 by the Institute. It is important for the reader to study and view each of these individual reports in relation to this overall line of research. An understanding of the complex nature of the learning disability condition only begins to emerge when each specific topic or finding is seen as a partial, but important, piece of a larger whole

    Toward the Development of an Intervention Model for Learning Disabled Adolescents

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    This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities

    An Epidemiological Study of Learning Disabled Adolescents in Secondary Schools: The Relationship of Family Factors to the Condition of Learning Disabilities

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    This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities.In recent years, professionals in the field of learning disabilities have begun to address the impact of learning disabilities on adolescents and young adults. Although substantial attention has been directed to the manifestations of learning disabilities in elementary school age populations, the significantly different and increasingly complex demands on adolescents both in and out of school necessitate the development of systematic research on this population. The University of Kansas Institute for Research in Learning Disabilities has collected a broad array of data to form an epidemiological data base on LD adolescents and young adults. Data have been collected from learning disabled, low-achieving, and normal-achieving adolescents as well as from their parents and teachers. In addition, information from the environmental setting of the LD adolescents which pertains to interventions applied on behalf of the student, relationships with others, conditions under which he/she operates and support systems available for his/her use has also been collected. These data have been considered in relation to data on specific learner characteristics to gain a more complete profile of the older LD individual. Research results presented in Research Reports 12 through 20 detail findings from this comprehensive epidemiology study conducted during 1979-80 by the Institute. It is important for the reader to study and view each of these individual reports in relation to this overall line of research. An understanding of the complex nature of the learning disability condition only begins to emerge when each specific topic or finding is seen as a partial, but important, piece of a larger whole

    Instructional Practices that Promote Acquisition and Generalization of Skills by Learning Disabled Adolescents

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    This research was published by the KU Center for Research on Learning, formerly known as the University of Kansas Institute for Research in Learning Disabilities.While most efforts in programming for learning disabled adolescents have been directed to the content of instructional offering, the authors identify procedures to promote acquisition and generalization of skills . Exemplified within a learning strategies model, the procedures outlined here stress acquisition of specific strategies through learning it in isolation and then applying it to controlled materials. The real effect of the instruction, however, is the degree to which the student can generalize the acquired strategy to the materials used in the regular classroom and to maintain the strategy over time. Specific procedures to promote generalization across settings and over time are identified and described. The acquisition and generalization procedures presented herein are currently being investigated by The University of Kansas Institute for Research in Learning Disabilities
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