Research and Advances
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Application of IBM 1620 EDP methods to the calculation of the formulation constants of complex ions
In the course of our work on the physical chemistry of histamine and related compounds, we have done extensive work involving potentiometric titration of systems of chelates of these ligands with various metallic ions, negative ions, and small molecules. The resulting data is used to calculate the stability constants in solution (1, 2, 3, 4). The mathematical calculations for a single titration require two to four hours when done on a desk calculator, even when the operator is experienced. This is a serious disadvantage of the technique. The more accurate methods of successive approximations and of simultaneous equations [2] are so time consuming that their routine use is impractical without the aid of a high speed computer.
Use of the disk file on stretch
The paper begins by briefly describing the Stretch (IBM 7030) computer with special emphasis given to the organization and operation of its input-output equipment. Physical characteristics of the two-disk system (4,194,304 72-bit words, 8 µsec-per-word transmission rate, etc.) are noted. Timing limitations due to arm motion and disk rotation are discussed.
Applications of disk usage are discussed separately for problem programs and for systems programs such as compilers and the supervisory program. Approximately 260,000 words of disk storage are reserved for the storage of systems programs and the subroutine library. Problem programs, however, are not currently filed on the disk.
Certain programming techniques are discussed for transmitting words between disk and core storage with minimum delaying and interruption of the arithmetic unit. Dumps on disk are considered for both recovery from computer malfunction and for mathematical or physical developments during the calculation.
Partioning algorithms for finite sets
The partitions of a set with n elements are represented by certain n-tuples of positive integers. Algorithms are described which generate without repetitions the n-tuples corresponding to: (1) all partitions of the given set, (2) all partitions of the given set into m or fewer sets (1 ≨ m ≨ n), and (3) all partitions of the given set into exactly m sets (1 ≨ m ≨ n).
An extension of Fibonaccian search to several variables
A technique which uses Fibonaccion search concepts has been developed to solve optimization problems involving unimodal functions of several variables. The technique has not been proven to be optimal in the sense that the one-dimensional Fibonaccion search is. However, it is valuable for certain kinds of calculations.
Computation’s development critical to our society
The ACM's growth continues: we are now at 13,000 members; expenses also grow. Our professional membership does not spring from a uniformly trained group as in mathematics or physics or even economics. Instead, our increasing membership comes from what I might call intellectual adventures—pioneers in an over-organized society—who see great futures in computing at all levels of aspiration.
A comparison of disks and tapes
The principal characteristics of current magnetic disks and tape units are summarized and compared. Some of the characteristics of disk files are illustrated in a sorting example and compared to a tapesort. The conclusion is presented that disk files are competitive to tapes in some important applications.
DATA-DIAL: two-way communication with computers from ordinary dial telphones
An operating system is described which allows users to call up a remotely located computer from ordinary dial telephones. No special hardware or connections are required at the users' telephones. Input to the computer is through the telephone dial; output from the computer is in spoken form. Results of a test with telephones in the Boston area are reported.
Report on proposed American standard flowchart symbols for information processing
This paper presents the essential contents of the Proposed American Standard Flowchart Symbols for Information Processing. This is the first proposed standard prepared by Subcommittee X3.6 on Problem Description and Analysis of the American Standards Association (ASA).
An experiment in automatic verification of programs
How effective is a compiler at replacing explicit verification, and what is the cost of this technique?
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