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This article presents several research papers related to computing machinery and computer programs. Designing a system for the analytic processing of mathematical functions around a central syntax processor and permitting the user to work within the context of mathematical syntax leads to a flexible system with a broad range of capabilities. One advantage of the approach mentioned in "A Syntax-Directed Approach to Automated Aids for Symbolic Math," by L. Clapp, is that the basic system can be developed without many a prior restrictions on the nature of the mathematical entities to be processed. Once the basic structure has been developed, the user is free to define and operate within his own system of mathematics by modifying or extending the syntax definitions. In the paper "Programming Languages, Logic and Cooperative Games," by L. Hodes, an application of computers is presented which is not restricted to a single problem area but is perhaps not general purpose enough to be considered programming language, even a problem-oriented one.

This article presents information on the winning papers of the first annual ACM Communications Student Paper Competition organized by the Association for Computing Machinery (ACM). First place was given to the paper "Generating Parsers for Affix Grammars," by David R. Crowe of the University of British Columbia. The prize included $250 cash, a trip to ACM 72 to receive the award in person, and a three-year subscription to the ACM serial publication of his choice. Second place was given to the paper "Political Redistricting by Computer," by Robert E. Helbig, Patrick K. Orr, and Robert R. Roediger of Washington University. The prize included $150 cash, and for each author a three-year subscription to the ACM serial publication of his choice. Third place was given to the paper "An Extensible Editor for a Small Machine with Disk Storage," by Arthur J. Benjamin of Brandeis University. The prize included $100 cash, and a three-year subscription to the ACM serial publication of his choice. All of the refereeing of Competition papers was done by graduate students at various colleges and universities.

This paper introduces the notion of usage counts, shows how usage counts can be developed by algorithms that eliminate redundant computations, and describes how usage counts can provide the basis for register allocation. The paper compares register allocation based on usage counts to other commonly used register allocation techniques, and presents evidence which shows that the usage count technique is significantly better than these other techniques. [ABSTRACT FROM AUTHOR]

This paper modifies an earlier algorithm for converting decision tables into flowcharts which minimize subsequent execution time when compiled into a computer program. The algorithms considered in this paper perform limited search and, accordingly, do not necessarily result in globally optimal solutions. However, the greater search effort needed to obtain a globally optimal solution for complex decision tables is usually not justified by sufficient savings in execution time. There is an analogy between the problem of converting decision tables into efficient flowcharts and the well-understood problem in information theory of noiseless coding. The results of the noiseless coding literature are used to explore the limitations of algorithms used to solve the decision table problem. The analogy between the two problems is also used to develop improvements to the information algorithm in extending the depth of search under certain conditions and in proposing additional conditions to be added to the decision table. Finally, the information algorithm is compared with an algorithm proposed in a recent paper by Verhelst. [ABSTRACT FROM AUTHOR]

The paper describes a scheme for symbolic manipulation of index expressions which arise as a by-product of the symbolic manipulation of expressions in the matrix calculi described by the authors in a previous paper. This scheme attempts program optimization by transforming the original algorithm rather than the machine code. The goal is to automatically generate code for handling the tedious address calculations necessitated by complicated data structures. The paper is therefore preoccupied with "indexing by position." The relationship of "indexing by name" and "indexing by position" is discussed. [ABSTRACT FROM AUTHOR]

This article presents information on various activities organized by the Association for Computing Machinery (ACM). The Fifth Annual Microprogramming Workshop will be held in the Illini Union of the University of Illinois at Urbana-Champaign on September 25 and 26. Sponsored by the ACM Special Interest Group on Microprogramming and the 555 Computer Society, this workshop provides a leading forum where active workers in the microprogramming area can hear several formal papers and participate in informal discussion groups oriented to specific topics. Professor Daniel L. Slotnick, director of the Center for Advanced Computation at the University of Illinois at Urbana-Champaign, will be the featured speaker at a banquet on September 25; his topic will be "Parallel Processing." The 1973 San Diego Biomedical Symposium will be held January 31 through February 2, 1973, at the Sheraton-Harbor Island Hotel, San Diego, California. The Symposium theme will be "Innovations in Biomedicine." Technical papers appropriate to the following sessions are invited: aids to clinical care, modeling and analysis, interpretation and data reduction, scanning and image processing, information engineering, and general innovations.

This paper discusses both the history and future of programming languages (= higher level languages). Some of the difficulties in writing such a history are indicated. A key part of the paper is a tree showing the chronological development of languages and their interrelationships, Reasons for the proliferation of languages are given. The major languages are listed with the reasons for their importance. A section on chronology indicates the happenings of the significant previous time periods and the major topics of 1972. [ABSTRACT FROM AUTHOR]

The article presents several research papers relating to algorithms. The paper "Greatest Common Divisor of n Integers and Multipliers" presents an algorithm which calculates the greatest common divisor, IGCD, of n integers. Details of the method and comparisons to other algorithms are also given. The algorithm is a new version of the Euclidean algorithm for n integers. The n-1 calculations of the greatest common divisor of two integers is accomplished by means of a modified version of the Blankinship algorithm. The paper "Exponential Integral Ei (x)" presents the results of one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, under Contract NAS7-100, sponsored by the National Aeronautics and Space Administration. It presents an algorithm which was compiled and executed without any modification on a UNIVAC 1108 computer. An unfortunate precedent has been set in several recent algorithms of using an illegal FORTRAN construction.

The American Standard Code for Information Interchange (ASCII) contains a number of control characters associated with the principle of code extension, that is, with the representation of Information which cannot be directly represented by means of the characters in the Code. The manner of use of these characters has not previously been completely described. This paper presents a set of mutually consistent philosophies regarding code extension applications, and suggests a corollary set of doctrines for the application of the code extension characters. Distinctions are drawn between code extension and such other concepts as "graphic substitution" or "syntactic representation" which are often used to meet similar requirements. Also covered are certain topics which are not truly concerned with code extension but which are often linked with it in discussion on code applications. The material In this paper is equally applicable in principle to the (proposed) ISO international 7-bit code for information interchange. [ABSTRACT FROM AUTHOR]

A previous paper presented an efficient algorithm, called the Recomputation Algorithm, for evaluating a rational expression to within any desired tolerance on a computer which performs variable-precision arithmetic operations. The Recomputation Algorithm can be applied to expressions involving any variable-precision operations having O(10-... + Σ ∣ε∣) error bounds, where p denotes the operation's precision and ε, denotes the error in the operation's with argument. This paper presents an efficient variable-precision exponential operation with an error bound of the above order. Other operations, such as log, sin, and cos, which have simple series expansions, can be handled similarly. [ABSTRACT FROM AUTHOR]

The article presents information on various chapters of the Association for Computing Machinery (ACM) across the U.S. The Greater Rio Grande Chapter of ACM has recently extracted from its files a list of the titles of all technical papers presented at Chapter meetings since its inception in 1957. Using a program developed by D.K. Robbins of Sandia Corp., a KWIC-type listing of permuted titles of these papers has been made. This listing has been distributed to all members of the Chapter. Topics and speakers at ACM Chapters across the U.S. indicate the current trends of interest in computer science and data processing. The ACM Tidewater Chapter is sponsoring this spring a professional development course on "Real-Time Computing." The course is given by the Chapter's professional development chairman, Cecil Frost, who is applications staff specialist for Control Data Corp. At its April 21, 1966 meeting, the Westchester-Fairfield Chapter heard William Orchard-Hays speak on "Linear Programming of Computational Techniques."

Sequencing to minimize mean finishing time (or mean time in system) is not only desirable to the user, but it also tends to minimize at each point in time the storage required to hold incomplete tasks. In this paper a deterministic model of independent tasks is introduced and new results are derived which extend and generalize the algorithms known for minimizing mean finishing time. In addition to presenting and analyzing new algorithms it is shown that the most general mean-finishing-time problem for independent tasks is polynomial complete, and hence unlikely to admit of a non-enumerative solution. [ABSTRACT FROM AUTHOR]

User-written programs on the Dartmouth Time-Sharing System can communicate with many remote terminals simultaneously and can control the interactions between these terminals. Such programs can be written using standard input and output instructions in any language available on the system. This paper describes how this multiple-terminal facility was implemented without requiring any changes in the system executive or in any of the system's compilers or interpreters. [ABSTRACT FROM AUTHOR]

This paper presents the goals and organization of a course about programming designed to provide entering students in a graduate program with a cultural enrichment in their professional lives. The students are expected to have taken at least two programming courses prior to this one and, therefore, to be familiar with at least two programming languages, both as students and users. Teaching someone how to program is similar to teaching him to play a musical instrument; neither skill can be taught—they must be learned. However, the teacher still serves several vital purposes: to present a set of rules for producing well-formed utterances; to offer numerous demonstrations of his own skill; and to function as an involved critic. Finally, the teacher is the source of information about the process in which the student is involved. [ABSTRACT FROM AUTHOR]

Users of linear programming computer codes have realized the necessity of evaluating the capacity, effectiveness, and accuracy of the solutions provided by such codes. Large scale linear programming codes at most installations are assumed to be generating correct solutions without ever having been "benche-marked" by test problems with known solutions. The reason for this fail- ure to adequately test the codes is that rarely are there large problems with known solutions readily available. This paper presents a theoretical justification and an illustrative implementation of a method for generating linear programming test problems with known solutions. The method permits the generation of test problems that are of arbitrary size and have a wide range of numerical characteristics. [ABSTRACT FROM AUTHOR]

Programming systems which permit arbitrary linked list structures enable the user to create complicated structures without sufficient protection. Deletions can result in unreachable data elements, and there is no guarantee that additions will be performed properly. To remedy this situation, this paper proposes a Data Structure Description and Manipulation Language which provides for the creation of a restricted class of data structures but ensures the correctness of the program. This is accomplished by an explicit structure declaration facility, a restriction on the permissible operations, and execution-time checks. [ABSTRACT FROM AUTHOR]

In certain data base organization schemes the cost per access may increase due to structural inefficiencies caused by updates. By reorganizing the data base the cost per access may be reduced. However, the high cost of a reorganization prohibits frequent reorganizations. This paper examines strategies for selecting the optimum reorganization points. [ABSTRACT FROM AUTHOR]

This paper presents the statistical results of tests of the accuracy of certain arithmetic systems in evaluating sums, products and inner products, and analytic error estimates for some of the computations. The arithmetic systems studied are 6-digit hexadecimal and 22-digit binary floating point number representations combined with the usual chop and round modes of arithmetic with various numbers of guard digits, and with a modified round mode with guard digits. In a certain sense, arithmetic systems differing only in their use of binary or hexadecimal number representations are shown to be approximately statistically equivalent in accuracy. Further, the usual round mode with guard digits is shown to be statistically superior in accuracy to the usual chop mode in all cases save one. The modified round mode is found to be superior to the chop mode in all cases. [ABSTRACT FROM AUTHOR]

This paper discusses the multiplication of conformable sequences of row vectors, column vectors, and square matrices. The minimum time required to evaluate such products on ordinary serial computers as well as parallel computers is discussed. Algorithms are presented which properly parse suck matrix sequences subject to the constraints of the machine organization. [ABSTRACT FROM AUTHOR]

An increasing amount of software is being implemented in a portable form. A popular way of accomplishing this is to encode the software in a specially designed machine-independent language and then to map this language, often using a macro processor, into the assembly language of each desired object machines The design of the machine-independent language is the key factor in this operation. This paper discusses the relative merits of pitching this language at a high level or a low level, and presents sonic comparative results. [ABSTRACT FROM AUTHOR]

Most current programming languages treat computation over different classes of objects (e.g. numbers, strings, labels and functions). For correct compilation and execution, the following question then arises: is a program properly constructed so that its operations and operands are compatible? The activity of answering this question is usually called type checking. This paper attempts to isolate the notion of type checking and presents a partial solution to the type checking problem based on the notions of abstraction and application of functions. In particular, a program is mapped into an expression within a decideable subset of the λ-calculus, which characterizes the type relations within the program and eliminates all other information The determination of the type-wise correctness or incorrectness of the program is resolved by reducing its corresponding λ-calculus expression to one of two normal forms, the constant "correct" for a type-wise correct program or the constant "error." An application to type checking in Algol 60 is made, and the attendant problems faced for any notion of type checking are discussed. [ABSTRACT FROM AUTHOR]

In list processing there is typically a growing demand for space during program execution. This paper examines the practical implications of this growth within a virtual memory computer system, proposes two new garbage collection techniques for virtual memory systems, and compares them with traditional methods by discussion and by simulation. [ABSTRACT FROM AUTHOR]

List processing systems should be designed to facilitate production of large programs to manipulate large complex symbolic data stores. This paper presents an overview of a number of system features which the author feels are important to improve the productivity of programmers working in such domains. A systems view is taken, rather than focusing just on language features, since algorithms must be not only coded in a language form, but debugged, modified, made efficient, and run on data Because of this general framework, the requirements specified are applicable to the design of advanced programming systems for a wide range of applications Three aspects of programming systems are highlighted good interactive facilities, programmable control structures, and sophisticated data communication mechanisms Interactive features are described to facilitate program composition, entry, testing, debugging, editing, optimization, and packaging. Implementation of a generalized environment structure model specified would allow programming of various control regimes including multi processes, coroutines and backtracking. Alternative methods of procedure invocation required include invocation by pattern and by monitoring condition. The need for extended data forms, storage management, and extensibility are stressed, as is the duality of data retrieval and function evaluation. Syntax directed input and output of data would facilitate use of complex data stores. [ABSTRACT FROM AUTHOR]

Various kinds of interference between communicating parallel processes have been examined by Dijkstra, Knuth and others. Solutions have been given for the mutual exclusion problem and associated subproblems, in the form of parallel programs, and informal proofs of correctness have been given for these solutions. In this paper a system of parallel processes is regarded as a machine which proceeds from one state S (i.e. a collection of pertinent data values and process configurations) to a next state 5' in accordance with a transition rule S ⇒ S . A set of such rules yields sequences of states, which dictate the system's behavior. The mutual exclusion problem and the associated subproblems are formulated as questions of inclusion between sets of states, or of the existence of certain sequences. A mechanical proof procedure is shown, which will either verify (prove the correctness of) or discredit (prove the incorrectness of) an attempted solution, with respect to any of the interference properties. It is shown how to calculate transition rules from the "partial rules" by which the individual processes operate. The formation of partial rules and the calculation of transition rules are both applicable to hardware processes as well as to software processes, and symmetry between processes is not required. [ABSTRACT FROM AUTHOR]

This paper presents an approach to writing specifications for parts of software systems. The main goal is to provide specifications sufficiently precise and complete that other pieces of software can be written to interact with the piece specified without additional information. The secondary goal is to include in the specification no more information than necessary to meet the first goal. The technique is illustrated by means of a variety of examples from a tutorial system. [ABSTRACT FROM AUTHOR]

A sequential pattern recognition (SPR) procedure does not test all the features of a pattern at once. Instead, it selects a feature to be tested. After receiving the result of that test, the procedure either classifies the unknown pattern or selects another feature to be tasted, etc. Medical diagnosis is an example of SPR. In this paper the authors suggest that SPR be viewed as a one-person game played against nature (chance). Virtually all the powerful techniques developed for searching two-person, strictly competitive game trees can easily be incorporated either directly or by analogy into SPR procedures. In particular, one can incorporate the "miniaverage backing-up procedure" and the "gamma procedure," which are the analogues of the minimax backing-up procedure and the alpha-beta procedure," respectively. Some computer simulated experiments in character recognition ore presented. The results indicate that the approach is promising. [ABSTRACT FROM AUTHOR]

Given the horizontal and vertical projections of a finite binary pattern f, can we reconstruct the original pattern f? In this paper we give a characterization of patterns that ore reconstructable from their projections. Three algorithms ore developed to reconstruct both unambiguous and ambiguous patterns, it is shown that an unambiguous pattern can be perfectly reconstructed in time m × n and that a pattern similar to an ambiguous pattern can also be constructed in time m × n, where m, n are the dimensions of the pattern frame. [ABSTRACT FROM AUTHOR]

That the pattern feature "width as a function of angle" possesses several possible interpretations is demonstrated in this paper, which is a review of the width concept in pattern recognition and the geometrical concept itself. The object of the work is to clarify how the word description can be made precise so that computer algorithms for feature extraction may be obtained; the focus is on theoretical subject matter. The results consist of a set-theoretic definition of width-at-angle, a theorem relating it to the pattern boundary radius vector, and descriptions of alternate widths. All widths are calculated for an illustrative example; graphical and tabular comparisons are given. Substantial variation in width-at-angle magnitude is found. The principal conclusion is that the set-theoretic width-at-angle is a useful pattern feature when it can be easily computed. Further investigation of the information contained in only port of a width function is recommended for cases where computation of width-at-angle is difficult. [ABSTRACT FROM AUTHOR]

In this paper trade-offs among certain computational factors in hash coding are analyzed. The paradigm problem considered is that of testing a series of messages one-by-one for membership in a given set of messages. Two new hash-coding methods are examined and compared with a particular conventional hash-coding method. The computational factors considered are the size of the hash area (space), the time required to identify a message as a nonmember of the given set (reject time), and an allowable error frequency. The new methods are intended to reduce the amount of space required to contain the hash-coded information from that associated with conventional methods. The reduction in space is accomplished by exploiting the possibility that a small fraction of errors of commission may be tolerable in some applications, in particular, applications in which a large amount of data is involved and a core resident hash area is consequently not feasible using conventional methods. in such applications, it is envisaged that overall performance could be improved by using a smaller core resident hash area in conjunction with the new methods and, when necessary, by using some secondary and perhaps time-consuming test to "catch" the small fraction of errors associated with the new methods. An example is discussed which illustrates possible areas of application for the new methods. Analysis of the paradigm problem demonstrates that allowing a small number of test messages to be falsely identified as members of the given set will permit a much smaller hash area to be used without increasing reject time. [ABSTRACT FROM AUTHOR]

Time-shared, multiprogrammed, and overlayed batch systems frequently require segmentation of computer programs into discrete portions. These program portions are transferred between executable and peripheral storage whenever necessary; segmentation of programs in a manner that reduces the frequency of such transfers is the subject of this paper. Segmentation techniques proposed by C. V. Ramamoorthy are subject to limitations that arise when the preferred segment size is not compatible with the physical restrictions imposed by the available computing equipment. A generalization of Ramamoorthy's suggestions is made in order to allow their ape plication when circumstances are other than ideal. [ABSTRACT FROM AUTHOR]

In this paper an attempt is made to explore the logical foundations of computer programming by use of techniques which were first applied in the study of geometry and have later been extended to other branches of mathematics. This involves the elucidation of sets of axioms and rules of inference which con be used in proofs of the properties of computer programs. Examples are given of such axioms and rules, and a formal proof of a simple theorem is displayed. Finally, it is argued that important advantages, both theoretical and practical, may follow from a pursuance of these topics. [ABSTRACT FROM AUTHOR]

In this general paper the role of programming in advanced graduate training is discussed. Subject matter related to programming as well as programming per se is considered. The importance and application of formalism are considered and also the need for good empirical experimentation. A brief outline for a sequence of courses is included, and subject headings that have been obtained from an extensive bibliography are given. A bibliography of programming references is included. [ABSTRACT FROM AUTHOR]

This paper is concerned with a review and examination of several existing algorithms for the zero-one programming problem. Computational experience is summarized. The machine time and storage requirements of several of the algorithms are compared over several test problems of small and intermediate size. Computer experiments still provide little hope of solving problems with over 100 variables with a reasonable amount of machine time. [ABSTRACT FROM AUTHOR]

ASP is a general purpose Associative Data Structure Package in which an arbitrary number of data items and an arbitrary number of the relationships between these data items may be represented. A special picture language is described which has proved very useful for drawing ASP structures on paper. ASP structures are built and manipulated by means of a series of macro coils, which are outlined in the Appendix. Emphasis is on the philosophy of the system rather than a particular implementation, though sufficient information is included to enable the reader to produce his own implementation of ASP. [ABSTRACT FROM AUTHOR]

This section presents news briefs related to the Association for Computing Machinery (ACM) in the U.S. Editor-in-chief William S. Dorn is soliciting papers for the tutorial and survey journal of the ACM. The ACM has decided to reprint "Proceedings of the Decision Tables Symposium, 1926." Paul Armer of RAND Corp. was elected president of the American Federation of Information Processing Societies.

In many recent computer system designs, hardware facilities have been provided for easing the problems of storage allocation. A method of characterizing dynamic storage allocation systems—according to the functional capabilities provided and the underlying techniques used—is presented. The basic purpose of the paper is to provide o useful perspective from which the utility of various hardware facilities may be assessed. A brief survey of storage allocation facilities in several representative computer systems is included as an appendix. [ABSTRACT FROM AUTHOR]

Reduction in the size of decision tables can be accomplished by several techniques. The techniques considered in this paper are on the parsing of decision tables with regard to horizontal and vertical data structures, job identity, hardware and job priorities, and context relationships. Such parsing rests upon some conventions for the linkage of decision tables. [ABSTRACT FROM AUTHOR]

Computer programming deals with an enormous variety of activities and is carried on by people with a great variety of backgrounds. It seems clear that part but not all of this activity h evolving toward a distinct professional field, but that the scope of this emerging profession, and some of its economic, social, and educational characteristics are as yet by no means well defined. In this paper, these issues are examined and some opinions about them are expressed. [ABSTRACT FROM AUTHOR]

For the nonprogrammer, difficulty in using language increases rapidly with the number of nonproblem-oriented conventions. A simple language, even if inelegant, which considers the user's background as part of the problem may be more effective than 'source language containing subtle and more powerful capabilities. The language described in this paper is used to write computer programs which test electronic equipment. Because this testing process contains few complex ideas, there is little need for the elegance and redundancy of a highly syntax-oriented language. A simple and direct language will suffice for the problem. The eventual users of this language are military depot personnel who cannot be expected to have computer programming skill or significant programming training. For this nonprogramming-oriented user, it was essential to create language using familiar engineering statements; programming- oriented conventions would have unnecessarily complicated his task. [ABSTRACT FROM AUTHOR]

When the transition has been mode from off line to online programming, there are a number of changes in the working conditions noted. These changes in the environment make necessary corresponding changes in the processes related to producing and checking out programs. In the main, it is not the programming language itself which must be changed to provide facility for the online user; it is the system surrounding the programming language. In this paper the online environment and its effect on programming ore discussed. [ABSTRACT FROM AUTHOR]

A descriptive scheme for classes of pictures based on labeling techniques using parallel processing algorithms was proposed by the author some years ago. Since then much work has been done in applying this to bubble chamber pictures. The parallel processing simulator, originally written for an IBM 7094 system, has now been rewritten for CDC 3600 system. This paper describes briefly the structure of syntactic descriptive models by considering their specific application to bubble chamber pictures. How the description generated in this phase can be embedded in a larger "conversation" program is explained by means of a certain specific example that has been worked out. A partial generative grammar for "handwritten" English letters is given, as are also a few computer-generated outputs using this grammar and the parallel processing simulator mentioned earlier. [ABSTRACT FROM AUTHOR]

This paper describes a technique designed to ease the use of a data processing system by a person, in particular, a scientist, who is intimately and primarily concerned with interpreting the significance of data handled by the system. Since such a person is often unable to spend the time necessary to master a programming language, it is essential that he be aided in composing commands to the computer. In the system described, the user is not required to learn or remember the vocabulary of the language because the vocabulary is displayed before him on "menus' by means of a computer-drive scope. He selects the various vocabulary elements required by pointing with the lightpen. By use of a small unordered set of rewriting rules applied as a result of lightpen selections, the user generates only syntactically correct commands to the system. He does not have to learn or remember the grammar. The program restricts the user severely in the particular language he can use, but the method for communicating with the program makes these restrictions seem quite natural and unconstraining. The program has been used successfully for over ten months. [ABSTRACT FROM AUTHOR]

The article presents information on the publication of a book "Applied Statistics, Algorithms," relevant to statistics, by the Royal Statistical Society in cooperation with the Science Research Council's Working Party on Statistical Computing. A policy statement describing the editorial policy appears in "Applied Statistics," Vol. 1. No. 1 (1968). A support paper describing the expected contents of the external specification and making recommendation for the layout of algorithms and for programming strategy will appear in the following issue.

Finite-length reference string of arbitrary structure are considered, and an exact expression for average working set size in terms of "corrected" interreference interval statistics is derived. An example is discussed; upper and lower bounds are obtained; and the average working set size function is shown to be efficiently obtained for a set of page sizes, in a single pass of the reference string. This work follows the developments of a paper by Denning and Schwartz, who consider infinite-length reference strings which satisfy certain statistical properties and who derive an expression relating the asymptotic average working set size to the asymptotic missing page rate function under working set replacement. [ABSTRACT FROM AUTHOR]

The article presents information about the schedule of events of the Association for Computing Machinery (ACM), related to the computer software industry. A four-day symposium on Computer Graphics in Medicine will he conducted by the ACM Special Interest Group for Computer Graphics. The symposium will be hosted by Point Park College in Pittsburgh, Pennsylvania, from March 7-10, 1972. A Symposium on Decision Making to be held in November 1972 has been announced by the Council for Cybernetics, Soviet Academy of Sciences and the Academy of Sciences of the Georgian Soviet Socialist Republic. ACM is cooperating in certain aspects of the planning for American papers and attendance, announced W. Smith Dorsey, chairman of the ACM Conferences and Symposia Committee. The ACM Special Interest Group on Computer Personnel Research will hold its Tenth Annual Conference at the Ontario Institute for Studies in Education of the University of Toronto from June 15-17, 1972. The Conference will focus on research findings, ease studies, and operating practices concerning computer personnel problems.

The article reports on developments concerning the activities of the Association for Computing Machinery (ACM) in the United States as of February 1971. ACM has responded to the dip in employment of computer professionals by initiating a program of professional placement seminars. Each seminar consists of three segments: a presentation by the seminar director; a panel discussion by placement and employer personnel followed by a question and answer period; and mock interview sessions conducted on an individual basis between panel members and attendees. Patrick C. Fischer has accepted from Editorial Board Chairman Eric Weiss appointment as Editor-in-Chief, Special Publications. Editor-in-Chief M. Stuart Lynn has announced that, to encourage interest in computer technology among college undergraduates, Communications will annually sponsor a Student Paper Competition.

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.