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IBM Journal of Research and Development

Issue 2 • Date March 1973

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Displaying Results 1 - 11 of 11
  • Empirically Derived Micromodels for Sequences of Page Exceptions

    Publication Year: 1973, Page(s):86 - 100
    Cited by:  Papers (15)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (756 KB)

    Based on a statistical analysis of actual computer program address traces, some results are presented of a study aimed at deriving empirically valid stochastic models for program reference patterns in a computer system operating under demand paging. For the address traces examined, a semi-Markov model for the (univariate) point process of page exceptions is formulated and found to be an adequate c... View full abstract»

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  • Bounds for Weight Balanced Trees

    Publication Year: 1973, Page(s):101 - 105
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (369 KB)

    It has been shown that the cost W of a weight balanced binary tree satisfies the inequalities, H ≤ W ≤ H + 3, where H is the entropy of the set of the leaves. For a class of “smooth” distributions the inequalities, H ≤ W ≤ H + 2, are derived.<p>These results imply that for sets with large entropy the search times provided by such trees cannot be su... View full abstract»

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  • Optimum Storage Allocation for a File with Open Addressing

    Publication Year: 1973, Page(s):106 - 114
    Cited by:  Papers (1)  |  Patents (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (431 KB)

    File organizations utilizing key-to-address transformation and open addressing are studied. A simulation method and a Markov model, which were used for evaluation, are presented. The cost of retrieval as a function of storage space and accesses is also formulated. The minimum of the combined costs for different operational conditions is determined. View full abstract»

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  • Quasimaximum Likelihood Estimators for Two-parameter Gamma Distributions

    Publication Year: 1973, Page(s):115 - 124
    Cited by:  Papers (4)  |  Patents (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (642 KB)

    The Gamma probability distribution is defined by the density function [βαγ(α)]−1 exp (−x/β). This paper presents new estimators for the parameters α−1 and β. Required calculations are simple, primarily involving the inner product of certain elementary statistics and their logarithms. Both of the ... View full abstract»

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  • Theory of MNOS Memory Device Behavior

    Publication Year: 1973, Page(s):125 - 134
    Cited by:  Papers (11)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (575 KB)

    This paper extends the direct-tunneling theory of MNOS memory device behavior to account for traps that are distributed both spatially and energetically. It shows that the Pulver and Dorda model is a special case of the Ross and Wallmark model, which is itself a restricted version of the more general theory proposed here. A general equation for the total charge transfer is derived, for monoenerget... View full abstract»

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  • Axioms and Theorems for a Theory of Arrays

    Publication Year: 1973, Page(s):135 - 175
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1292 KB)

    Array theory combines APL with set theory, transfinite arithmetic, and operationally transformed functions to produce an axiomatic theory in which the theorems hold for all arrays having any finite number of axes of arbitrary countable ordinal lengths. The items of an array are again arrays. The treatment of ordinal numbers and letters is similar to Quine's treatment of individuals in set theory. ... View full abstract»

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  • Automatic Equalizers having Minimum Adjustment Time

    Publication Year: 1973, Page(s):176 - 179
    Cited by:  Patents (1)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (323 KB)

    Two new types of automatic equalizers for telephone lines are discussed. The modular configurations shown are designed for minimum adjustment time and are ready to receive data as soon as the response of the unequalized line has been measured. Two forms of such equalizers are compared with respect to upper bounds on the residual distortion. View full abstract»

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  • Recent Papers by IBM Authors

    Publication Year: 1973, Page(s):180 - 184
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (380 KB)

    Reprints of the papers listed here can usually be obtained by writing directly to the authors. The authors' IBM divisions are identified as follows: ASDD is the Advanced Systems Development Division: DPD, Data Processing Division: FED, Field Engineering Division; FSD, Federal Systems Division; GPD General Products Division; GSD, General Systems Division: OPD, Ofice Products Division: RES, Research... View full abstract»

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  • Recent IBM Patents

    Publication Year: 1973, Page(s):185 - 187
    IEEE is not the copyright holder of this material | PDF file iconPDF (285 KB)
    Freely Available from IEEE
  • Authors

    Publication Year: 1973, Page(s):188 - 189
    IEEE is not the copyright holder of this material | PDF file iconPDF (230 KB)
    Freely Available from IEEE
  • Contents of previous issues

    Publication Year: 1973, Page(s):190 - 193
    IEEE is not the copyright holder of this material | PDF file iconPDF (278 KB)
    Freely Available from IEEE

Aims & Scope

The IBM Journal of Research and Development is a peer-reviewed technical journal, published bimonthly, which features the work of authors in the science, technology and engineering of information systems.

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Editor-in-Chief
Clifford A. Pickover
IBM T. J. Watson Research Center