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The article presents information on several conferences and symposiums on computer programs. The National Science Foundation has awarded a grant of $50,500 for a Conference on Computers in the Undergraduate Curricula. It is intended to aid dissemination of plans and actual experiences in the use of computers in under graduate education, particularly in small two and four-year colleges. The Twelfth Annual Symposium on Switching and Automata Theory will be held in East Lansing, Michigan, on October 13-15, 1971. Papers are being sought, describing original research in general areas of switching theory, automata theory, and the theoretical aspects of computers, computation and programming.

The decomposition of a complex data transmission system into segments and the identification of the terminal configurations employed on each segment appear to offer promise as a powerful tool for permitting and clarifying measurements and comparisons of the performance of like system segments, and for describing the features of systems which are significant to performance measurements. Many problem areas remain, however, for further study. For example, the question of combining the individual performance measures of a multisegment, multi-mode-of-operation system into a meaningful measure of total systems performance appears quite formidable. It is the intent of the Task Group to approach these problems of performance measurement gradually and to resolve them first for the simpler systems before proceeding to complex system configurations. Although the techniques which this Task Group has evolved for system description may appear to be voluminous or even redundant when applied to very simple configurations, they are orderly, and every effort has been made to seek and exploit the "common denominators" of data transmission systems having arbitrary degrees of complexity. We doubt that much further compaction can be realized without, severely curtailing or destroying the generality and (hopefully) universal applicability of these methods. The format which has been described is admittedly incomplete. It is suggestive rather than exhaustive. It is believed that its chief virtue lies in the identification of an orderly succession of levels of abstraction which permits the regular decomposition of highly complex systems into functional subgroupings having a size structure within the span of human attention. The details of description outlined within these subgroupings require further study and elucidation and it will probably always be necessary for the system describer Io employ good judgment and imagination in extending the scope of description in those areas where new advances, unique applications and/or common sense so dictate. [ABSTRACT FROM AUTHOR]

Focuses on an American Standards Association task group's second tutorial paper on the subject of performance of systems used for data transmission. Determination of transfer rate of information bits; Orderly arrangement of characteristics and parameters that affect information throughput.

The paper describes a technique for compacting character sets in a digital computer while retaining fast access to individual bits. It considers the problem of minimizing the storage needed to contain such tables. Reduction techniques are developed, and the problem is shown to reduce to a covering problem. [ABSTRACT FROM AUTHOR]

This article presents information related to the 5th Annual Symposium of the San Francisco Bay Area Chapter of ACM. On October 29, 1965, the topic "Computers--Software for Online Systems," was discussed. Over 300 people attended this symposium which reflects the great interest in the topic. The papers given represented the broad interests in the time-sharing field of the diverse organizations from government, business and universities. The impact of online systems has been felt in each of these areas. The Octopus operating system for the Control Data 6600 is one of the first steps at Lawrence Radiation Laboratory, Livermore, California, to interconnect various types of computers and storage devices. This system provides a response within reasonable time to users located at remote teletypes. Up to 100 programs are known to the system at one time, of which ten are active and in main core. Programming the Octopus system has required two calendar-years and fifteen man-years.

This article reports on the proceedings of an Association for Computing Machinery (ACM)'s SIGFIDET Workshop on Data Description, Access and Control which was convened in Ann Arbor, Michigan, during May 1-3, 1974. The convention featured a debate on the differences and similarities between the data structure set model and the relational model for data management systems. Educators C. W. Bachman and E. F. Codd were the two principals in the debate who were joined by E. Sibley and J. Lucking, on the one side, and V. K. Whitney and D. Tsichritzis, on the other. The moderator was R. Rustin. The discussion ranged over most of the relevant issues and topics, except possibly one posed by the moderator beforehand, that is, "Do databases eat their young?" Bachman took the position that the two points of view are perhaps two sides of the same coin, and that which is more natural depends on stylistic preferences. Other sessions on several related subjects featured contributed papers.

An algorithm is described for reducing the generalized eigenvalue problem Ax = λBx to an ordinary problem, in case A and B are symmetric hand matrices with B positive definite. If n is the order of the matrix and m the bandwidth, the matrices A and B are partitioned into m-by-m blocks; and the algorithm is described in terms of these blocks. The algorithm reduces the generalized problem to an ordinary eigenvalue problem for a symmetric hand matrix C whose bandwidth is the same as A and B. The algorithm is similar to those of Rutishauser and Schwartz for the reduction of symmetric matrices to band form. The calculation of C requires order n²m operation. The round-off error in the calculation of C is of the same order as the sum of the errors at each of the n2m steps of the algorithm, the latter errors being largely determined by the condition of B with respect to inversion. [ABSTRACT FROM AUTHOR]

The article reports on the provisions of the Proposed American Standard which distinguishes the character structure and character parity sense for parallel-by-bit data communication in American Standard Code for Information Interchange (ASCII). The standard includes, among others, provision on its applicability, standard character structure, and standard bit-to-channel relationship. Specifically, the standard is applicable to general information interchange involving Data Processing Terminal Equipment and Data Communication Equipment.

The author comments on the transmission of information. He says that the incorporation of automata and state diagrams in information transmission can be useful. He believes that the general theory of transmission automata can be created to detail the features of different schemes. He argues that it is possible to develop proof procedures to determine performance characteristics and for the reliability of automata.

The article presents information on some of the special events related to computing. The Fifteenth Annual Symposium on Switching and Automata Theory will be held in October 1974 in New Orleans. The First Illinois Conference on Medical Information Systems will take place in October 1974 in Illinois. The second Annual System Engineering Conference will be held in Minneapolis in November 1974. The Image Pattern Recognition Workshop will take place in November 1974 in San Diego, California. The Canadian Computer Show and Conference will be held in Montreal, in November 1974. International Meeting on Mini-Computers and Data Communication will take place in January 1975 in Belgium. The American Mathematical Society Annual Meeting will be held in January 1975 in Washington D.C. International Conference on Reliable Software will take place in Los Angeles, California in April 1975. The Third International Optical Computing Symposium will be held in April 1975 in Washington D.C. The Fourth Symposium on Operating System Principles will be held in Yorktown Heights, New York in October 1975.

Focuses on a procedure for achieving reliable full-duplex data transmission over half-duplex links. Automata for the simplex scheme; Infallibility of the National Physical Laboratory scheme; Need for more research on transmission control and error recovery techniques.

Methods for the compact representation of contour plots are described and tested. These are intended to reduce the cost of transmitting contour plots over phone lines. We feel some of these methods could be used to transmit contour plots over voice grade phone lines. [ABSTRACT FROM AUTHOR]

Future systems that combine computers, digital terminals, and communications equipment present design optimization problems that require reconsideration of the traditional functional responsibilities of the respective subsystems. Several "standard" interfaces, by means of which computers and digital terminals connect to the communications systems will be required. When specifying these interfaces, consideration must be given to problems of coordination, synchronization, error control, signaling, stream multiplexing, and switch control, in addition to minimizing the technological interdependence of specific subsystem designs. A focus on some of the problems is obtained in a discussion of a detailed specification for a particular computer-communications system interface. [ABSTRACT FROM AUTHOR]

Future users of large data banks must be protected from having to know how the data is organized in the machine (the internal representation). A prompting service which supplies such information is not a satisfactory solution. Activities of users at terminals and most application programs should remain unaffected when the internal representation of data is changed and even when some aspects of the external representation are changed. Changes in data representation will often be needed as a result of changes in query, update, and report traffic and natural growth in the types of stored information Existing noninferential, formatted data systems provide users with tree-structured files or slightly more general network models of the data. In Section 1, inadequacies of these models are discussed. A model based on n-ary relations, a normal form for data base relations, and the concept of a universal data sublanguage are introduced. In Section 2, certain operations on relations (other than logical inference) are discussed and applied to the problems of redundancy and consistency in the user's model. [ABSTRACT FROM AUTHOR]

An alternative approach to the design and organization of a general purpose interactive multiterminal computing system is presented. The system organization described is a conceptually simple arrangement of a bank of interchangeable computers, each of which is a memory/proputor pair, that are assigned to process terminal jobs as they arrive. One of the computers serves as the master or control computer and supervises the collection and distribution of messages from and to the remote terminals. In the simplest form there is a disk drive for each connected terminal. A crosspoint switching network allows any such disk drive to be connected to any computer in the bank, under control of the control computer. Thus, while each active terminal user "occupies" a dedicated disk drive, he may share the computer with many other terminal users in a simple manner. The ratio of users to computers is dependent on both the size and power of the machines used and the computation requirements of the particular mix of users. This system organization is inherently a simpler and therefore more reliable approach to time-sharing computers and has the potential of a highly available system at relatively low cost. Economic configurations are possible for a range of systems sizes that span at least one order of magnitude. Finally, problem programs developed by remote terminal users can be run on a dedicated batch system if compatible computers ore used. [ABSTRACT FROM AUTHOR]

This article focuses on the proposed USA Standard, which presents control procedures for the data communication systems. This employs the USA Standard Code (SC) for Information Interchange. It is intended for systems that are controlled through the use of the communication control characters provided in USASCII. Other standards have been adopted or are being developed which prescribe the character structure, bit sequencing, signaling speed, message format, and other parameters vital to the communication of information in a data system. In the development of this standard both historical and present data communication practices were considered. In addition, consideration was given to the requirements for future systems and to the applicable standards being developed internationally. This standard is intended for systems that are controlled through the use of the communication control characters provided in USASCII. This standard specifies a variety of data communication control procedures to meet the needs of data communication links having different configurations or complexity.

A technique for simulating the detailed logic networks of large and active digital systems is described. Essential objectives sought ore improved ease and economy in model generation, economy in execution time and space, and a facility for handling simultaneous activities. The main results obtained are a clear and useful separation of structural and behavioral model description, a reduction of manual tasks in converting Boolean logic into a structural model, the elimination of manual processes in achieving exclusive simulation of activity, an event-scheduling technique which does not deteriorate in economy as the event queue grows in length, and a simulation procedure which deals effectively with any mixture of serial and simultaneous activities. The passage of time is simulated in a precise, quantitative fashion, and systems to be simulated may be combinations of synchronous and asynchronous logic. Certain aspects of the techniques described may be used for the simulation of network structures other than digital networks. [ABSTRACT FROM AUTHOR]

Presents a field-proven scheme for achieving reliable duplex transmission over a half-duplex telephone communication line. Flowchart for the reliable scheme with examples; Difficulty of the problem due to the necessity of sending control, error and verification information over the same noisy line that first caused an error.

Focuses on the control procedures for data communication systems. Advantage of the standard message format; Impact of originating interface on communication systems; Standardization of the control procedures.

The article describes the American Standard Code for Information Interchange (ASCII). This standard specifies the character structure and sense of character parity for serial-by-bit, serial-by-character synchronous and asynchronous data communication in the ASCII. This standard applies to general information interchange at the interface between Data Processing Terminal Equipment and Data Communication Equipment (such as data sets, modems). The character structure for synchronous data communication shall consist of eight bits (seven ASCII bits plus one character parity bit), having equal time intervals. The character structure for asynchronous data communication shall consist of 10 signal elements having equal time intervals; "0" (spacing) start element, seven ASCII bits, one character parity bit, and one "1" (marking) stop element. The intercharacter interval (the time interval between the end of a stop element). The intercharacter interval (the time interval between the end of a stop element and the beginning of the next start element) may be of any length, and is of the same sense as the stop element, i.e., 1 (marking).

Presents the considerations of Task Group X3.3.4 in the area of transparent-mode data communications control philosophy. Elaboration of solutions to the problems of transparency to the basic ASCII communication control characters; Control problems of handling material such as offline encrypted data or non-ASCII codes by means of systems providing complete character transparency.

The article focuses on the first world computer chess championship organized at the IFIP Congress in 1974. After four years of domination of computer chess in the Association for Computing Machinery sponsored U.S. Computer Chess Championships, CHESS 4.0 of Northwestern University fell to defeat at the teletype of CHAOS from Univac. In winning this first-of-a-kind international tournament, the Soviet team represented by Mikhail Donskoy, took home a gold medal. The tournament site was the Hotel Birger Jarl in central Stockholm. The games were analyzed for the audience by David Levy, the tournament director, on display boards supplied by the Swedish Chess Federation. At each teletype cathode-ray tube terminal, or telephone was a flag showing the competing country. Thirteen programs were entered in the tournament and were run on computers located all over Europe. The most exciting game of the tournament was the final one between KAISSA and OSTRICH from Columbia University. The tournament was organized by professor Benjamin Mittman of Northwestern University, David Levy, an international chess master from London, and professor Monty Newborn.

This article presents news briefs related to the computer industry in several countries. A contract to design and manage the implementation of a COBOL compiler for the Electrologica ELX 8 computer has been awarded to Informatics Inc. The total value of the contract will exceed $200,000. The Postgraduate School of Librarianship, University of Sheffield, England, has been awarded a substantial grant by the Office for Scientific and Technical Information, Department of Education and Science in London, to carry out an 18 months study of the education and training requirements for scientific and technological library and information work. Proposed American Standard "Character Structure and Character Parity Sense for Parallel-by-Bit Data Communication in ASCII" will appear in the September 1966 issue of the journal "Communications of the ACM." John G. Honig of the U.S. Arms Control and Disarmament Agency began his term as president of the Washington Operations Research Council in June 1966.

Deals with evolution of a method for transmitting data of a type originating in many laboratory situations direct to a central computer. Utilization of any ordinary telephone on a 'callup' basis; Present applications of data transmission system.

The article focuses on developments related to data transmission systems in Great Britain. British communications services are intended to remain under the firm control of GPO, the Great Britain Post Office. GPO control of data transmission has raised the fear that a nationwide network will not materialize if data transmission services continue to be provided at the present slow rate. Underlying much of the GPO's need for gradualism is the limited capacity of the national telephone network. This network, which is used by at least two thirds of installed terminals, was originally designed to accommodate vocal messages averaging three minutes in length. This time period has served as a standard in determining future investments in equipment. However, the average duration of a single computer/teletype interexchange is 25 minutes. Thus, the operation of a single computer linked to 80 terminals going through the same switchboard would be the equivalent of 600 to 700 voice communications. The British telephone network's capabilities are being increased to serve the expansion of data traffic.