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IBM Journal of Research and Development

Issue 3 • Date July 1961

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Displaying Results 1 - 11 of 11
  • A 0.7-Microsecond Ferrite Core Memory

    Publication Year: 1961, Page(s):174 - 182
    Cited by:  Papers (3)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (946 KB)

    The design and performance of a newly developed magnetic core memory is described. A two-dimensional array organization and partial switching of toroidal cores were employed in the design of this low-power, high-speed memory. The memory features a unique combination of a current-steering diode matrix and a load-sharing magnetic switch for an economical and high-performance drive system. The operat... View full abstract»

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  • Irreversibility and Heat Generation in the Computing Process

    Publication Year: 1961, Page(s):183 - 191
    Cited by:  Papers (498)  |  Patents (4)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (953 KB)

    It is argued that computing machines inevitably involve devices which perform logical functions that do not have a single-valued inverse. This logical irreversibility is associated with physical irreversibility and requires a minimal heat generation, per machine cycle, typically of the order of kT for each irreversible function. This dissipation serves the purpose of standardizing signals and maki... View full abstract»

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  • A Table Look-up Machine for Processing of Natural Languages

    Publication Year: 1961, Page(s):192 - 203
    Cited by:  Papers (2)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (1210 KB)

    A table look-up machine based upon a photographic memory is being optimized for the processing of natural languages. It makes use of automatic retrieval of lexical information by means of novel addressing features which allow look-up of phrases regardless of length. Linguistic determinations made on the basis of the lexical information retrieved govern subsequent operations. In addition a sentence... View full abstract»

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  • An Approximate Method for Treating a Class of Multiqueue Problems

    Publication Year: 1961, Page(s):204 - 209
    Cited by:  Papers (20)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (660 KB)

    The following problem is considered: N queues of unrestricted length are served in cyclic order by a single server. Input to each queue is Poisson, the service time distribution may be arbitrary, and a finite time is required by the server to go from one queue to the next. Supposing that at any queue the server serves all units which he finds when he arrives, what is the probability pn ... View full abstract»

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  • Notes on Cumulative Photovoltages

    Publication Year: 1961, Page(s):210 - 217
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (863 KB)

    It is reasoned that the large photovoltages observed by Cheroff and Keller on ZnS crystals are theoretically plausible and can result from a wide class of different mechanisms. Conversely, the conditions under which a photoconductor with periodic inhomogeneities does not show a cumulative photovoltage are shown to be very restrictive and improbable. General theorems concerning the magnitude of the... View full abstract»

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  • The Use of Radioisotopes to Determine the Chemistry of Solder Flux

    Publication Year: 1961, Page(s):218 - 225
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (865 KB)

    When rosin flux activated with amine halides is used in soldering printed circuit boards, metal halides are formed; these halides cannot be removed with organic solvents and thus may cause corrosion. The use of alkanol amines as solder fluxes has been investigated. After soldering, the flux can be removed by rinsing with water. Throughout this investigation radioisotopes were used to identify the ... View full abstract»

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  • Bistable Systems of Differential Equations with Applications to Tunnel Diode Circuits

    Publication Year: 1961, Page(s):226 - 240
    Cited by:  Papers (14)
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (983 KB)

    A mathematical analysis is developed for nonlinear circuits which have at least two stable steady states, and therefore are of interest as computing or memory elements. Circuits containing one or two tunnel diodes will be analyzed in detail as applications of the theory. The method is based on the study of certain “potential function” whose extrema are the steady states of the circui... View full abstract»

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  • Minimum Polarized Distance Codes

    Publication Year: 1961, Page(s):241 - 248
    IEEE is not the copyright holder of this material | Click to expandAbstract | PDF file iconPDF (677 KB)

    The choice of a code for a given application is influenced by many factors, such as economics, compatibility, and reliability. This paper is concerned solely with the reliability of codes, and shows how, for a given number of bits per character and a given minimum distance, the probability of undetected error in an asymmetric channel may be reduced by many orders of magnitude merely by the proper ... View full abstract»

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  • IBM Technical Papers Published in Other Journals

    Publication Year: 1961, Page(s):249 - 260
    IEEE is not the copyright holder of this material | PDF file iconPDF (1358 KB)
    Freely Available from IEEE
  • Recent IBM Patents

    Publication Year: 1961, Page(s):261 - 262
    IEEE is not the copyright holder of this material | PDF file iconPDF (257 KB)
    Freely Available from IEEE
  • Authors

    Publication Year: 1961, Page(s):263 - 264
    IEEE is not the copyright holder of this material | PDF file iconPDF (294 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