Misplaced Pages

#983016

44-610: During World War II, International Business Machines Corporation (IBM) funded and built an Automatic Sequence Controlled Calculator (ASCC) for Howard H. Aiken at Harvard University . The machine, formally dedicated in August 1944, was widely known as the Harvard Mark I . The President of IBM, Thomas J. Watson Sr. , did not like Aiken's press release that gave no credit to IBM for its funding and engineering effort. Watson and Aiken decided to go their separate ways, and IBM began work on

88-568: A radio technician and became interested in mathematics. He graduated from Columbia University with a bachelor's degree in 1949 and a master's degree in 1950, both in mathematics, and joined IBM in 1950. During his first three years, he worked on the Selective Sequence Electronic Calculator (SSEC) ; his first major project was to write a program to calculate positions of the Moon . In 1953, Backus developed

132-500: A meritorious career of pioneering contributions to the development and application of large-scale digital computers and important contributions to education in the digital computer field." In addition to his work on the Mark series, another important contribution of Aiken's was the introduction of a master's program for computer science at Harvard in 1947, nearly a decade before the programs began to appear in other universities. This became

176-591: A project to build their own larger and more visible machine. Astronomer Wallace John Eckert of Columbia University provided specifications for the new machine; the project budget of almost $ 1 million was an immense amount for the time. Francis "Frank" E. Hamilton (1898–1972) supervised the construction of both the ASCC and the SSEC. Robert Rex Seeber Jr. was also hired away from the Harvard group, and became known as

220-671: A starting ground to future computer scientists, many of whom did doctoral dissertations under Aiken. Howard Aiken married three times: to Louise Mancill in June 1937, then later to Agnes Montgomery, and lastly to Mary McFarland. He had two children; one with his first wife, and one with his second. Howard Aiken was also a Commander in the United States Navy Reserve . After he retired at age 60 to Fort Lauderdale, Florida , Aiken continued his contributions to technology. He founded Howard Aiken Industries Incorporated, which

264-479: A successor to FP. FL was an internal IBM research project, and development of the language stopped when the project was finished. Only a few papers documenting it remain, and the source code of the compiler described in them was not made public. FL was at odds with functional programming languages being developed in the 1980s, most of which were based on the lambda calculus and static typing systems instead of, as in APL,

308-782: A wealthy and established Indiana family, and Margaret Emily Mierisch, whose parents were German immigrants. He grew up in Indianapolis where he graduated from Arsenal Technical High School in 1919. Aiken studied at the University of Wisconsin–Madison where he received his B.S. in electrical engineering in 1923. He later obtained his M.A. and Ph.D. degrees in physics from Harvard University in 1937 and 1939, respectively. During this time, he encountered differential equations that he could only solve numerically. Inspired by Charles Babbage 's difference engine , he envisioned an electro-mechanical computing device that could do much of

352-439: A women's shoe store. The noisy SSEC was sometimes called Poppa by the viewing pedestrians. It was dedicated and first demonstrated to the public on January 27, 1948. A. Wayne Brooke served as the chief electronic engineer for the machine's operation starting in 1950. Herb Grosch , the second person with a Ph.D. hired by IBM, was one of its first programmers. Another early programmer was Edgar "Ted" Codd . Elizabeth "Betsy" Stewart

396-827: The Ferranti Mark I was marketed in the UK as a commercial computer using Williams tube technology, followed by the UNIVAC I using delay-line memory in the US. These memory technologies allowed stored-program features to be more practical. The stored-program concept had been first widely published in 1945 in the First Draft of a Report on the EDVAC and became known as the Von Neumann architecture . The EDVAC (first working in 1949)

440-717: The Harvard Mark II computer. He continued his work on the Mark III and the Harvard Mark IV . The Mark III used some electronic components and the Mark IV was all-electronic. The Mark III and Mark IV used magnetic drum memory and the Mark IV also had magnetic-core memory . Aiken accumulated honorary degrees at the University of Wisconsin, Wayne State University and Technische Hochschule, Darmstadt . He

484-554: The development of compilers . A few deviations from this approach were tried (notably in Lisp and APL ), but by the 1970s, Backus–Naur context-free specifications for computer languages had become quite standard, following the development of automated compiler generators such as yacc . This contribution helped Backus win the Turing Award in 1977. Backus later worked on a function-level programming language known as FP , which

SECTION 10

#1732772420984

528-584: The SSEC was General Electric . The SSEC was also used for calculations by the U.S. Atomic Energy Commission for the ANP project to power an airplane with a nuclear reactor. Robert D. Richtmyer of Los Alamos National Laboratory used the SSEC for some of the first large-scale applications of the Monte Carlo method . Llewellyn Thomas solved problems with stability of laminar flow , programmed by Donald A. Quarles Jr. and Phyllis K. Brown. In 1949, Cuthbert Hurd

572-625: The SSEC was seen as a problem, and IBM soon licensed the Williams tube technology developed on the Manchester Baby at the Victoria University of Manchester . Subsequent computers would have electronic random access memory , and in fact the ability to execute instructions from processor registers was generally not adopted. The 77-bit wide programming word was also abandoned for fewer bits but much faster operation. By 1951

616-513: The Supplement to the AE 1968. Taken together, the corrections thus referenced modify practically every individual element of the lunar computations, and thus the space program appears to have been using lunar data generated by a modified and corrected derivative of the computational procedure pioneered using the SSEC, rather than the directly resulting tables themselves. The first paying customer of

660-767: The chief architect of the new machine. Modules were manufactured in IBM's facility at Endicott, New York , under Director of Engineering John McPherson after the basic design was ready in December 1945. The February 1946 announcement of the fully electronic ENIAC energized the project. The new machine, called the IBM Selective Sequence Electronic Calculator (SSEC), was ready to be installed by August 1947. Watson called such machines calculators because computer then referred to humans employed to perform calculations and he wanted to convey

704-573: The end of 1948 a new IBM 604 multiplier was announced, which used newer tube technology that already made the bulky tubes of the SSEC obsolete. By May 1949 the Card-Programmed Electronic Calculator was announced, and shipped in September. It was effectively a much scaled-down version of the SSEC technology to allow customers to perform similar calculations. Even by the end of 1948, the limited electronic memory of

748-419: The film Walk East on Beacon , which is based on a book by J. Edgar Hoover . It was widely covered positively by the press. The SSEC attracted both customers and new employees. Both Hurd and Backus were hired after seeing demonstrations of the facility. The 1946 ENIAC had more tubes than the SSEC and was faster in some operations, but was originally less flexible, needing to be rewired for each new problem. At

792-452: The first stored-program computer . The first application of the SSEC was calculating the positions of the Moon and planets , known as an ephemeris . Each position of the Moon required about 11,000 additions, 9,000 multiplications, and 2,000 table look-ups, which took the SSEC about seven minutes. This application used the machine for about six months; by then other users were lined up to keep

836-567: The language Speedcoding , the first high-level language created for an IBM computer, to aid in software development for the IBM 701 computer. Programming was very difficult at this time, and in 1954 Backus assembled a team to define and develop Fortran for the IBM 704 computer. Fortran was the first high-level programming language to be put to broad use. This widely used language made computers practical and accessible machines for scientists and others without requiring them to have deep knowledge of

880-563: The machine busy. It has sometimes been said that the SSEC produced the Moon-position tables that were later used for plotting the course of the 1969 Apollo flight to the Moon. Records closer to 1969 suggest, however, that while there was a relationship, it was most likely less immediate. Thus, Mulholland and Devine (1968), working at NASA Jet Propulsion Laboratory , reported that the JPL Ephemeris Tape System

924-512: The machinery. Backus served on the international committees that developed ALGOL 58 and the very influential ALGOL 60 , which quickly became the de facto worldwide standard for publishing algorithms . Backus developed the Backus–Naur form (BNF), published in the UNESCO report on ALGOL 58. It was a formal notation able to describe any context-free programming language, and was important in

SECTION 20

#1732772420984

968-478: The message that IBM's machines were not designed to replace people. Rather they were designed to help people, by relieving them of drudgery. The SSEC was installed on three sides of a room on the ground floor of a building near IBM's headquarters at 590 Madison Avenue in New York City , behind a large window where it was visible to people passing by on the busy street. The space had formerly been occupied by

1012-507: The paper tape memory made programming the SSEC more like the calculators from the World War II era. For example, "loops" were usually literal loops of paper tape glued together. For each new program, tapes and card decks were literally "loaded" on the readers, and a plugboard changed in the printer to modify output formatting. For these reasons, the SSEC is usually classified as the last of the "programmable calculator" machines instead of

1056-479: The people who had programmed it could see how to get it running again”. ENIAC co-designer J. Presper Eckert (no relation to the IBM Eckert) called it "some big monstrosity over there that I don't think ever worked right". Seeber had carefully designed the SSEC to treat instructions as data, so they could be modified and stored under program control. IBM filed a patent based on the SSEC on January 19, 1949, which

1100-474: The quoted 400,000 digit capacity was in the form of reels of punched paper tape. Addition took 285 microseconds and multiplication 20 milliseconds, making arithmetic operations much faster than the Harvard Mark I. Data that had to be retrieved quickly was held in electronic circuits; the remainder was stored in relays and as holes in three continuous card-stock tapes that filled another wall. A chain hoist

1144-455: The rank of corporal, being put in command of an anti-aircraft battery stationed at Fort Stewart , Georgia . After receiving high scores on a military aptitude test, the Army sent him to study engineering at the University of Pittsburgh . He later transferred to a pre-medical program at Haverford College . During an internship at a hospital, he was diagnosed with a cranial bone tumor , which

1188-529: The same Endicott team who developed the SSEC. Howard H. Aiken Howard Hathaway Aiken (March 8, 1900 – March 14, 1973) was an American physicist and a pioneer in computing . He was the original conceptual designer behind IBM 's Harvard Mark I , the United States' first programmable computer . Aiken was born on 8 March 1900, in Hoboken, New Jersey , to Daniel Aiken, who came from

1232-444: The same as traditional functional programming style languages. FP was strongly inspired by Kenneth E. Iverson 's APL , even using a non-standard character set . An FP interpreter was distributed with the 4.2BSD Unix operating system, but there were relatively few implementations of the language, most of which were used for educational purposes. Backus spent the latter part of his career developing FL (from "Function Level"),

1276-469: The tedious work for him. This computer was originally called the ASCC (Automatic Sequence Controlled Calculator) and later renamed Harvard Mark I . With engineering, construction, and funding from IBM , the machine was completed and installed at Harvard in February 1944. Richard Milton Bloch , Robert Campbell and Grace Hopper joined the project later as programmers. In 1947, Aiken completed his work on

1320-403: The two side rows were used for sprockets. The familiar 80 columns of IBM punched card technology were recorded sideways as one column of the tape. Using well-tested technology, the SSEC's calculations were accurate and precise for its time, but one early programmer, John Backus , said "you had to be there the entire time the program was running, because it would stop every three minutes, and only

1364-660: The von Neumann Style?" The IEEE awarded Backus the W. W. McDowell Award in 1967 for the development of FORTRAN. He received the National Medal of Science in 1975 and the 1977 Turing Award "for profound, influential, and lasting contributions to the design of practical high-level programming systems, notably through his work on FORTRAN, and for publication of formal procedures for the specification of programming languages". John Backus retired in 1991. He died at his home in Ashland, Oregon on March 17, 2007. Backus

IBM SSEC - Misplaced Pages Continue

1408-616: Was "used for virtually all computations of spacecraft trajectories in the US space program", and that it had, as its current lunar ephemeris, an evaluation of the Improved Lunar Ephemeris incorporating a number of corrections: sources are named as 'The Improved Lunar Ephemeris' (documentation which was the report of the Eckert computations carried out by the SSEC, complete with lunar position results from 1952 to 1971), with corrections as described by Eckert et al. (1966), and in

1452-547: Was a consulting firm that helped failing businesses recover. During his years in Florida, he joined the University of Miami as a Distinguished Professor of Information. In addition, Aiken became a consultant for companies such as Lockheed Martin and Monsanto . On the morning of March 14, 1973, Aiken died in his sleep during a consulting trip to St. Louis, Missouri . His widow, Mary, died in 2013. John Backus John Warner Backus (December 3, 1924 – March 17, 2007)

1496-447: Was an American computer scientist . He led the team that invented and implemented FORTRAN , the first widely used high-level programming language , and was the inventor of the Backus–Naur form (BNF), a widely used notation to define syntaxes of formal languages . He later did research into the function-level programming paradigm, presenting his findings in his influential 1977 Turing Award lecture "Can Programming Be Liberated from

1540-579: Was born in Philadelphia and grew up in nearby Wilmington, Delaware . He studied at The Hill School in Pottstown, Pennsylvania , but he was apparently not a diligent student. He entered college at the University of Virginia to study chemistry , but struggled with his classes there, and he was expelled after less than a year for poor attendance. He was subsequently conscripted into the U.S. Army during World War II , and eventually came to hold

1584-463: Was chief operator, and often appeared in publicity photos. The SSEC was an unusual hybrid of vacuum tubes and electromechanical relays . Approximately 12,500 vacuum tubes were used in the arithmetic unit, control, and its eight (relatively high-speed) registers , which had an access time of less than one millisecond . About 21,400 relays were used for control and 150 lower-speed registers, with an access time of 20 milliseconds. The relay technology

1628-447: Was described in his Turing Award lecture "Can Programming be Liberated from the von Neumann Style ?". Sometimes viewed as Backus's apology for creating Fortran, this paper did less to garner interest in the FP language than to spark research into functional programming in general. When Backus publicized the function-level style of programming, his message was mostly misunderstood as being

1672-748: Was elected a Fellow of the American Academy of Arts and Sciences in 1947. He received the University of Wisconsin–Madison College of Engineering Engineers Day Award in 1958, the Harry H. Goode Memorial Award in 1964, the Golden Plate Award of the American Academy of Achievement in 1965, the John Price Wetherill Medal in 1964, and the IEEE (Institute of Electrical and Electronics Engineers) Edison Medal in 1970 "For

1716-468: Was hired (also after a visit to the SSEC) and started a department of applied science; the operation of SSEC was eventually put into that organization. The SSEC room was one of the first computers to use a raised floor , so visitors would not see unsightly cables or trip over them. The large array of flashing lights and noisy electro-mechanical relays made IBM very visible to the public. The SSEC appeared in

1760-551: Was later upheld as supporting the machine's stored program ability. Each instruction could take input from any source (electronic or mechanical registers or tape readers) store the result in any destination (electronic or mechanical registers, tape or card punch or printer), and gave the address of the next instruction, which could also be any source. This made it powerful in theory. However, in practice instructions were stored usually on paper tape, resulting in an overall rate of only about 50 instructions per second . The serial nature of

1804-532: Was needed to lift the heavy reels of paper into place. The machine read instructions or data from 30 paper tape readers connected to three punches, and another a table look-up unit consisted of another 36 paper tape readers. A punched card reader was used to load data, and results were produced on punched cards or high-speed printers. The 19-digit word was stored on the card stock tape or registers in binary-coded decimal , resulting in 76 bits, with two extra bits for indicating positive or negative sign and parity, while

IBM SSEC - Misplaced Pages Continue

1848-432: Was similar to the ASCC, based on technology invented by Clair D. Lake (1888–1958). The arithmetic logic unit of the SSEC was a modified IBM 603 electronic multiplier, which had been designed by James W. Bryce . The bulky tubes were military surplus radar technology, which filled one entire wall. The memory was organized as signed 19-digit decimal numbers. Multiplication was computed with 14 digits in each factor. Most of

1892-497: Was successfully removed, and a plate was installed in his head. He then moved to the Flower and Fifth Avenue Medical School for medical school, but found it uninteresting and dropped out after nine months. He soon underwent a second operation to replace the metal plate in his head with one of his own design, and received an honorable medical discharge from the U.S. Army in 1946. After moving to New York City he trained initially as

1936-604: Was the ENIAC successor, designed by the team who then marketed the UNIVAC. The SSEC ran until August 1952, when it was dismantled, having been made obsolete by fully electronic computers. An IBM 701 computer, known as the Defense Calculator, was installed in the same room for its April 7, 1953, public debut. In July 1953 the much less expensive (and even better selling) IBM 650 was announced, which had been developed by

#983016