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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.

The section presents a calendar of professional activities for the computer industry. The 1974 Harry Goode Memorial Award was presented to professor Edsger W. Dijkstra. The Pacific Regional Symposium will be held at Totem Park Convention Centre. A Workshop on Interactive Computer Graphics is being sponsored by the Association for Computing Machinery Special Interest Group in Computer Graphics.

With the advent of on-line (time-sharing) computer systems and graphic terminals, we have available a new dimension in numerical problem solving capabilities. Rather than simply use the new power to achieve fast turnaround, we can develop interactive routines which are easy to use and also take advantage of the insight and visual capabilities of the human problem solver. Several on-line systems for general purpose mathematical problem solving have already been implemented as well as some special purpose systems for solving problems in a particular area such as ordinary differential equations. The advantage of restricting the problem area is that the interface with a user can be greatly simplified, in this paper we discuss some of the advantages accrued by such systems and design considerations for interactive routines. Furthermore, an implementation of an on-line least squares data-fitting program, PEG, is presented with results obtained from empirical data. In conclusion, areas for future work in this field are discussed. [ABSTRACT FROM AUTHOR]

This article presents information on various events related to computer science. A symposium on Electronic Composition in Printing will be held at the National Bureau of Standards in Gaithersburg, Maryland on June 15-16, 1967. Emphasis will be on the state of the art, new machines in development, and research and applications both in and out of government. The Southeastern Regional Meeting of the Association for Computing Machinery (ACM) will be held jointly with the National Meeting of the Biological Information Organization at the University of North Carolina in Chapel Hill, North Carolina, on June 15-17. The previously announced ACM Symposium on the "Design and Implementation of Interactive Systems for Experimental Applied Mathematics," will be held on August 26-28, 1967, just prior to the ACM National Conference at the Sheraton-Park Hotel in Washington D.C. A Computer Graphics Conference will be held on the Urbana campus of the University of Illinois, November 6-8, 1967. The conference will be aimed at participants with some knowledge of the scope and methods of computer graphics.

A television-like scanned-display system has been successfully Implemented on a Honeywell DDP424 computer installation. The scanned image is stored in the core memory of the computer, and software scan conversion is used to convert the rectangular coordinates of a point to the appropriate word and bit In an output display array in core storage. Results thus far Indicate that flicker-free displays of large amounts of data are possible with reasonably fast graphical interaction. A scanned Image of size 240 X 254 points is displayed at a 30 frame-per-second rate. [ABSTRACT FROM AUTHOR]

This section presents a calendar of international events related to computer science from June 1968 to August 1972. The Computer Graphics International Symposium will be held at Brunel University in Uxbridge, England. The 31st Annual Meeting of the American Society for Information Science will be held at Sheraton-Columbus Hotel in Ohio. The Association for Computing Machinery National Conference will be held at the Sheraton-Boston in Massachusetts.

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]

Raster scan computer graphics with"real time" character generators have previously been limited to alphanumeric characters. A display has been described which extends the capabilities of this organization to include general graphics. Two fundamentally different scan conversion algorithms which have been developed to support this display are presented. One is most suitable to non- interactive applications and the other to Interactive applications. The algorithms were implemented in Fortran on the CDC6400 computer. Results obtained from the implementations show that the non interactive algorithms can significantly reduce display file storage requirements at little cost in execution time over that of a conventional raster display. The interactive algorithm can improve response time and reduce storage requirements. [ABSTRACT FROM AUTHOR]

Describes a scan conversion algorithm that uses a linked list data structure to process the lines of the drawing in strips corresponding to groups of scan lines. Form of display file of most graphic systems using a raster scan output device; Translation of the picture description from the XY format to the raster format; Memory buffer area used to accumulate the binary image for a group of scan lines; Line drawing analysis.

This article presents information on various events related to computer science. Society for Industrial and Applied Mathematics Meeting will be held during June 11 and 15, 1967 in Washington. Association of Data Processing Service Organizations Conference will be held in Abingdon, Panama during June 15-16, 1967. Symposium on Computer Control of Natural Resources and Public Utilities, that will be held in September 1967, in Israel. 1968 Spring Joint Computer Conference will be held during 30 April and 2 May, 1967.

A method of converting a picture into a "cartoon" S S or map whose regions correspond to differently textured regions is described. Texture edges in the pica hire are detected, and solid regions surrounded by these (usually broken) edges are "colored in" using a propagation process. The resulting map is cleaned by comparing the region colors with the textures of the corresponding regions in the picture, and also by merging some regions with others according to criteria based on topology and size. The method has been applied to the construction of cloud cover maps from cloud cover pictures obtained by satellites. [ABSTRACT FROM AUTHOR]

The problem of automatic digitizing of contour maps is discussed. The structure of a general contour map is analyzed, and its topological properties are utilized in developing a new scanning algorithm. The problem of detection and recognition of contour lines is solved by a two color labeling method. It Is shown that for maps containing normal contour lines only, it suffices to distinguish between so-called "even" and "odd" lines. The "tangency problem" involved in practical scanning is discussed, and a solution based on minimizing computer memory space and simplifying control program Is suggested. [ABSTRACT FROM AUTHOR]

The tremendous output of the high-speed computer has far outstripped the modern executive's ability to examine, absorb, and use all the information generated in his day-to-day decision making. But this imbalance between the machine and the manager is now being corrected through the development of computer graphics. In this article, the authors examine a number of different plotting techniques--from two-dimensional pictorial maps to 3-D model making and from black and white to full color. The great advantage is that with graphics the data output can be communicated to the manager in more comprehensible, intelligible, and usable ways than by conventional computer reports. [ABSTRACT FROM PUBLISHER]

The availability of interactive, three dimensional, computer graphics systems coupled to powerful digital computers encourages the development of algorithms adapted to this environment. Pictorial pattern recognition techniques make possible a number of approaches to X-ray structure determination based on molecular model building, i.e. the use of chemical information to frame "structural hypotheses" which can computationally be tested and refined by reference to the experimental data. Application of standard pattern recognition algorithms is hindered by the fact that the cross-correlation between a model and the correct structure cannot be computed because of a fundamental incompleteness in the measured data. However, it is possible to compute an upper bound to such a cross-correlation. A simple example demonstrates that this information can be the basis of a technique for structure determination that can make effective use of an interactive graphics system. Model building by cross-correlations has intrinsic advantages over usual crystallographic techniques based on the autocorrelation or Patterson function, especially for large structures. This is significant, for crystallography of biological macromolecules has been and will continue to be a field of intense interest. [ABSTRACT FROM AUTHOR]

A calendar of events for the Association for Computing Machinery (ACM) is presented. The ACM Annual Symposium on Computers and Urban Society will be held at New York Hilton Hotel on October 29, 1971. A symposium on the application of computer graphics in biomedical systems and research will take place in Pennsylvania on March 7-10, 1972. During the first week of May 1972, a symposium on research will be conducted in Colorado.

Discusses problems with the use of structured display files in interactive computer graphics. Suggestion for an alternative approach to display system design; Definition of picture elements; Processing of inputs from pointing devices.

Display system designers are faced with the difficult task of selecting major subsystems in an intelligent way. Each subsystem is chosen from large numbers of alternatives; the selection is based on considerations such as system response time, system cost, and the distribution of data storage and processing between the graphics processor and its supporting data processing system. The work reported here develops an objective, quantitative design procedure and helps give a better understanding of how to configure display systems. This is accomplished by means of a mathematical model of a computer driven graphics system. The parameters of the model are functions of the capabilities of the graphics hardware and of the computational requirements of the graphics application. The model can be analyzed using numerical queueing analysis or simulation to obtain an average response time prediction. By combining the model with an optimization, the best graphics system configuration, subject to a cost constraint, is found for several applications. The optimum configurations are in turn used to find general display system design guidelines. [ABSTRACT FROM AUTHOR]

Introduces an on-line two-dimensional film animation system called Animator. Features of the animation system; Advantages of computer animation techniques; Production of graphical output on location.

Describes an algorithm for producing computer generated half-tone presentations of three-dimensional polygonal surface structures. Advantages over the Warmock algorithm; Comparison of algorithm with computer runs achieved by the Warmock approach; Extension of algorithm to variable position illumination sources.

Focuses on the applicability of computer graphic languages and other types of data structures in space planning. Nonnumerical aspects of space design and planning problems; Attributes of a computer graphic language.

Describes an interactive graphical display monitor in a batch-processing environment with remote entry. Ability to respond from a user program where routine calls take the place of manual actions; Interaction between human and program in a symmetrical and equal basis through the medium of the graphic monitor; Choices in designing the graphic monitor given the existence of hardware and computer system constraints.

The algorithm presented causes the elimination of hidden lines in the representation of a perspective view of concave and convex plane-faced objects on the picture plane. All the edges of the objects are considered sequentially, and oil planes which hide every point of an edge are found. The computing time increases roughly as the square of the number of edges. The algorithm takes advantage of reduced number of concave points and automatically recognizes if only one object with no concave points is considered. In this last case, the result is obtained in a much simpler way. [ABSTRACT FROM AUTHOR]

A system developed at Harvard for graphically inputting and outputting nonstandard characters on a computer is printed. In principle, the system can deal with any orthography, although at present it is limited to 4000 Chinese characters and some mathematical symbols. New characters can be added to the repertoire of the system by graphical input on a display scope. Text inputting is accomplished via a display scope or a Rand Tablet. The organization and operation of the current system are described, and a discussion of the relative merits of such a system is given. Illustrations of the computer input and output of Chinese characters are included. [ABSTRACT FROM AUTHOR]

The flexibility of a mathematical model takes advantage of the common information requirements of computer-aided engineering drawing, numerical control tape generation, and physical characteristic computation. By judicious control of man-machine communication requirements, improved results over conventional engineering design processes are possible. An English-like input language, tailored for use by draftsmen and designers, will describe the part and specify the output desired. One approach to the mathematical model consists of a group of surface-defining quadric equations, which are created by a system of modular subprograms. Other sub-programs will convert the mathematical model into instructions for driving automatic drafting machines and numerical controlled machine tools. Physical part characteristics, such as center of gravity, can be computed by subprograms and used in dynamic analysis work. The proposed overall system is presented and experiments and demonstrations are discussed. [ABSTRACT FROM AUTHOR]

The article presents news related to the Association for Computing Machinery (ACM). The ACM has named Donald E. Knuth the recipient of the 1974 A.M. Turing Award, for his outstanding contributions of a technical nature to the computing community. The award is presented annually by ACM to an individual whose technical contributions have had a significant influence on a major segment of the computer field. During the past two years, ACM has negotiated joint-membership agreements with the computing societies of Italy, Germany, Israel, and Australia and most recently, with the IEEE Computer Society. The agreement between ACM and IEEE entitles regular members of each society to a $5 reduction in each other's dues. The success of the Conference on Computer Graphics and Interactive Techniques held in July 1974 has shown that graphics is an established and important part of the computer environment. The conference was held at the University of Colorado, Boulder. The accomplishments of those working to provide a useful tool in the form of a graphics display system were reported.

The article presents information about the organization of several events related to computer science, as of January 1, 1972. The National Microfilm Association Mid-Winter Meeting will be held from January 26-28, 1972 in San Diego, California. The Seventh Annual Conference on Use of Digital Computers in Process Control, will be held from February 9-11, 1972 in Baton Rouge, Louisiana. The Third Ontario Universities Computing Conference will be held from February 24-25, 1972 in Toronto, Ontario. The American Management Association's 18th Annual Systems Management Conference, will be held from March 6-8, 1972 in New York City. The Symposium on Computer Graphics in Medicine, will be held from March 7-10, 1972 in Pittsburgh, Pennsylvania. The Association for Systems Management Spring Conference, will be held from March 8-9, 1972 in Toronto, Ontario. The Symposium on Complexity of Computer Computations, will be held from March 20-22, 1972 in Yorktown Heights, New York. The First European Conference on Computational Physics will be held from April 10-14, 1972 in Geneva, Switzerland.

A stereographic display terminal has been produced using the raster display (BRAD) recently developed at Brookhaven. The system uses a rotating refresh memory to feed standard television monitors. To produce a stereographic display the computer calculates the projected video images of an object, viewed from two separated paints. The resulting video maps are stored on separate refresh bands of the rotating memory. The two output signals are connected to separate color guns of a color television monitor, thus creating superimposed image on the screen. Optical separation is achieved by viewing the image through color filters. The display is interactive and can be viewed by a large group of people at the same time. [ABSTRACT FROM AUTHOR]

This article presents a list of several forthcoming events related to the computing machinery. The One-Day Symposium of the Eastern Section of ACM SICCOSIM is going to be held on August 7 in Washington. The Seminar on Programming Techniques for Interactive Computer Graphics is going to be held from August 12-13 in Scotland. The Western Electronic Show and Convention is going to be held from August 20-23 in Los Angeles, California. The 20th Annual Conference on Quality Control and Statistics in Industry is going to be held on September 7 in New Jersey.

A calendar of events for computer-related matters in 1971-1972 is presented. Lehigh University's Open Workshop on Fault Detection and Diagnosis of Digital Systems will be held on December 7-18, 1971. The Computer-Aided Design-Computer Graphics Exhibition will be held on January 31-February 4, 1972. The International Symposium on Fault-Tolerant Computing will be held on June 19-21, 1972.

The article offers information on the introduction of a new department, Graphics and Image Processing, by the journal "Communications of the ACM." William Newman has been appointed as the editor and the department is stated to cover five principal areas. Key areas include hardware and software techniques for producing pictorial output, methodology for the digitization and input of pictorial information, languages and techniques for interacting with graphical systems, methodology for the digital processing and storage of such information, and so on.