Scheduled System Maintenance:
On Monday, April 27th, IEEE Xplore will undergo scheduled maintenance from 1:00 PM - 3:00 PM ET (17:00 - 19:00 UTC). No interruption in service is anticipated.
By Topic

IBM Journal of Research and Development

Issue 1 • Date Jan. 1993

Filter Results

Displaying Results 1 - 5 of 5
  • Architecture and performance of the ESPER-2 hard-disk drive servo writer

    Publication Year: 1993 , Page(s): 3 - 11
    Cited by:  Papers (5)  |  Patents (7)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1071 KB)  

    The servo writer is known as the most accurate and sensitive tool on an HDD (hard-disk drive) manufacturing line. ESPER-2 is designed as a product-independent common servo writer which incorporates major advances in equipment cost, reduction of clean-room requirements, and writing accuracy. The servo writing process consists of two stages. The first stage writes the master servo pattern on as many as ten disks at once with little need for contaminant protection facilities. One such master disk is then assembled with other, raw, disks in a file, and the second stage writes the proper servo pattern on all disk surfaces by referring to the master. The effects of off-center discursions in the mechanical disk assembly and random runout (NRRO, or nonrepeatable runout) in the product spindle components are eliminated by table-lookup servo actuator control, so that writing accuracy is improved. Neither an exceptionally clean environment nor fine mechanical parts are required for the second-stage operation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Proof of correctness of high-performance 3—1 interlock collapsing ALUs

    Publication Year: 1993 , Page(s): 12 - 21
    Cited by:  Papers (3)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1015 KB)  

    A 32-bit 3—1 interlock collapsing ALU, proposed to allow the execution of two interlocked ALU-type instructions in one machine cycle using an instruction-level parallel machine implementation, is shown to produce results equivalent to a serial execution of the instructions using a 2—1 ALU. The equivalence is shown by deriving tables which represent all possible requirements for the serial execution of the instructions followed by the generalization of the table to represent sets of instructions rather than the individual instructions themselves. Consequently, the equivalence of the 3—1 interlock collapsing ALU operations with these generalized requirements of the serial execution of the instructions is shown. The correctness of a proposed high-speed interlock collapsing ALU is thereby demonstrated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electrical characterization and performance limits of a flexible cable

    Publication Year: 1993 , Page(s): 22 - 38
    Cited by:  Papers (7)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (2738 KB)  

    The electrical performance of a flexible-cable test structure is characterized from low frequencies up to 25 GHz. The experimental results are used to develop and refine models which describe the performance of such cables, with particular emphasis on the contribution of dielectric and resistive losses, including skin effect. The capability of triplate flexible cables to provide high-bandwidth connections over long lengths is investigated with the models developed. A triplate design is chosen because it offers high density, limited crosstalk, no loss through radiation, and relatively inexpensive fabrication. Bit rates of 100 Mb/s-1 Gb/s are considered for propagation over lengths up to 250 cm. The paper highlights the performance-limiting factors through realistic examples, including the contribution of interfaces to other interconnection structures. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Recent publications by IBM authors

    Publication Year: 1993 , Page(s): 39 - 74
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (4564 KB)  

    The information listed here is supplied by the Institute for Scientific Information and other outside sources. Reprints of the papers may be obtained by writing directly to the first author cited. Journals and books are listed alphabetically title; papers are listed sequentially for each journal. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Recent IBM patents

    Publication Year: 1993 , Page(s): 75 - 80
    Save to Project icon | PDF file iconPDF (636 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.

Full Aims & Scope

Meet Our Editors

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