Communications of the ACM

ACM president's letter: H.R. 109

Peter J. Denning
Pages 409-410

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Operating system support for database management

Several operating system services are examined with a view toward their applicability to support of database management functions. These services include buffer pool management; the file system; scheduling, process management … Michael Stonebraker
Pages 412-418

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The proposed new Computing Reviews classification scheme

Anthony Ralston
Pages 419-433

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Report of the public cryptography study group

Peter J. Denning, David H. Brandin, Daniel C. Schwartz, George I. Davida
Pages 434-450

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Representing super-sparse matrices with perturbed values

This paper describes a form of purposeful data perturbation in a linear programming model which pertains to uncertainties in the magnitudes of the matrix coefficients. A problem in value pool construction is described first,  … Harvey J. Greenberg, Richard P. O'Neill
Pages 451-456

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Polynomial manipulation with APL

A simple but effective method for the manipulation of polynomials of several variables in APL is presented. The method is especially advantageous in situations where more sophisticated symbolic computing systems such as SAC-1 … Brian Billard
Pages 457-465

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On the security of multiple encryption

Double encryption has been suggested to strengthen the Federal Data Encryption Standard (DES). A recent proposal suggests that using two 56-bit keys but enciphering 3 times (encrypt with a first key, decrypt with a second key … Ralph C. Merkle, Martin E. Hellman
Pages 465-467

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technical correspondence: on message passes in computer networks. author's response

Glenn Ricart
Pages 468-469

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Technical correspondence: on message passes in computer networks.

Ernest Chang
Page 468

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ACM forum

Pages 475-482

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