ppxscal/embedding_network huggingface dataset:
Keyed files for databases in Sharp APL
Authors: M. Elliott
Venue: Proceedings of the eighth international conference on APL (1976)

This paper describes a file system which is used widely in Massey-Ferguson to implement nontrivial files. It has been used for data bases of all sizes, the largest of which are several megabytes. As a result of using this file system in all our major systems we have found several benefits, including: - - new databases can be designed and implemented very rapidly indeed - often in a matter of hours - using standard keyed file functions. - The design of the keyed file usually relates closely to the &ldquo;real world&rdquo;, making the system very transparent and maintainable. This contrasts with complex indexing structures which - while they may indeed be more efficient than keyed files - usually make the database incomprehensible to anyone who has not studied it at length. Keyed files are simple to use, understand and document. The structure of one of our largest databases can be easily described in a few sentences, and understood immediately by anyone familiar with the keyed file system. - We can quite easily make our systems communicate with each other (at the technical level). The paper begins with an outline of the Sharp APL File Subsystem, on which keyed files are based. It then describes the keyed files approach, including the design objectives. The conceptual structure of a keyed file is illustrated. All keyed files - whatever their particular manifestation - have this structure. The next section discusses some of the considerations in designing a keyed file, and indicates some of the limitations of the system. The paper closes with an example of an application, describing how the database is structured to face the problems it is used to solve. The author has worked for Massey-Ferguson since 1961 and first became involved with computers in 1963. He has programmed in many languages for several different computers. He was the pioneer of APL when it was introduced to the Corporate Head Office of MF in 1972. The language is now used for almost all Corporate systems, and for many planning and monitoring systems in other locations. These systems range from long-range planning models to daily monitoring systems to special one-off analyses, and vary in size from a few lines to several thousand lines of APL code.
Teaching operating systems and machine architecture&mdash;more on the hands-on laboratory approach
Authors: Malcolm G. Lane
Venue: Proceedings of the twelfth SIGCSE technical symposium on Computer science education (1981)

The &ldquo;hands-on&rdquo; laboratory approach to teaching operating systems has been used at West Virginia University since August 1971 [3, 6, 8]. In 1977 a Digital Equipment Corporation (DEC) PDP-11/34 system replaced the IBM 1130 system previously used for the course. The course is now using an (DEC) LSI-11 and is much improved. This paper focuses on the student projects which are the major part of the course. The &ldquo;hands-on&rdquo; laboratory course as currently being taught is discussed and compared to other techniques for teaching operating systems.
Interfacing APL and SQL
Authors: Brian Hagenbuch, Martin Gardner
Venue: ACM SIGAPL APL Quote Quad (1983)

We briefly argue that APL and a relational DBMS are a natural match for application development. We consider four pragmatic questions of interfacing APL and SQL: representation of query results, representation of SQL statements, SQL parameterization, and context control. We conclude with a brief mention of three APL/SQL implementations: one complete, one in progress, and one proposed. We do not discuss the fascinating question of how relational DBMS functions might be added as APL language extensions.
A difference in efficiency between synchronous and asynchronous systems
Authors: Eshrat Arjomandi, Michael J. Fischer, Nancy A. Lynch
Venue: Proceedings of the thirteenth annual ACM symposium on Theory of computing (1981)

A system of parallel processes is said to be synchronous if all processes run using the same clock, and it is asynchronous if each process has its own independent clock. For any s, n, a particular distributed problem is defined involving system behavior at n &ldquo;ports&rdquo;. This problem can be solved in time s by a synchronous system but requires time at least (s-1) log n on any asynchronous system.
The recognition of Series Parallel digraphs
Authors: Jacobo Valdes, Robert E. Tarjan, Eugene L. Lawler
Venue: Proceedings of the eleventh annual ACM symposium on Theory of computing (1979)

We present an algorithm that recognizes the class of General Series Parallel digraphs and runs in time proportional to the size of its input. To perform this recognition task it is necessary to compute the transitive reduction and transitive closure of any General Series Parallel digraph. Our analysis is based on the relationship between General Series Parallel digraphs and a class of well known models of electrical networks.
On determining the genus of a graph in O(v O(g)) steps(Preliminary Report)
Authors: I. S. Filotti, Gary L. Miller, John Reif
Venue: Proceedings of the eleventh annual ACM symposium on Theory of computing (1979)

In this paper we present an algorithm which on input a graph G and a positive integer g finds an embedding of G on a surface on genius g, if such an embedding exists. This algorithm runs in (v) O(g) steps where v is the number of vertices of G. We believe that removing the nondiscrete topological definitions (i.e., the notation or differentiability, 2-dimensional surface, etc.) from our formal definitions has a multitude of advantages. First our goal is to produce an algorithm which operates on discrete machines and thus at some point we must remove these notions anyway. Secondly, demonstrations on proofs in the amalgam of graph theory and topology have been riddled with flaws (e.g., 4-color theorem, planarity algorithms, Jordan curve theorem), and which, no doubt, this paper also suffers. The hope is that a combinatorial proof may transcend these problems. Third, our main goal is not just to draw graphs on &ldquo;inner tubes&rdquo; but to understand how graph theory, topology and computational complexity interact. We have kept no definitions sacred and we have redefined the notion of a graph. We have even rewritten Euler's formula.
Combining database management and statistical subroutinesunto a user-oriented data analysis facility (abstract only)
Authors: Marek Rusinkiewizc
Venue: Proceedings of the joint conference on Easier and more productive use of computer systems. (Part - I): Information processing in the social sciences and humanities - Volume 1981 (1981)

Most database management systems (DBMS) offer convenient and flexible data structures and very good data maintenance facilities. At the same time their data manipulation languages are usually limited and most data analysis applications require extensive programming in a host language. On the other hand, the packages of statistical subroutines (PSS) usually have very good data manipulation and analysis facilities, while at the same time they lack the well known advantages of DBMS. An attempt was made to combine the data definition and maintenance facilities of DBMS and the data manipulation and analysis facilities of PSS into a single user-oriented system. The additional software developed for this purpose performs the following functions:1. Allows the user to define his own analysis and (optionally) store it in a library for further reference.2. Allows the user to define the data on which analysis is to be performed.3. Allows the user to execute the (predefined) analysis in the following way:a. the user's description of analysis is translated into a sequence of data analysis and/or data manipulation subroutines of PSS.b. the required data are retrieved from a database under the control of DBMS and put into a temporary file, whose structure is determined by the analysis input requirements.c. the analysis is performed under the control of the executing program PSS.The outlined system is now being implemented, as an interdepartmental effort, in The Institute for Organization of the Medicine Industry, Warsaw, Poland. It utilizes IMS/VS as a database management system and the OSIRIS III package for statistical data processing. Although the system is still under development it is used not only by research workers but also by administrators and management for relatively simple analysis which are not routinely performed, standard reports. The main advantages of the outlined approach can be summarized as follows:a. reduction of time and cost of preparing the analysis,b. increasing the reliabilityc. presenting the tool for the actual decision makers to perform their own data analysis without the interference with programmers.
Simulation methods for Poisson processes in nonstationary systems
Authors: Peter A.W. Lewis, Gerald S. Shedler
Venue: Proceedings of the 10th conference on Winter simulation - Volume 1 (1978)

The nonhomogeneous Poisson process is a widely used model for a series of events (stochastic point process) in which the &ldquo;rate&rdquo; or &ldquo;intensity&rdquo; of occurrence of points varies, usually with time. The process has the characteristic properties that the number of points in any finite set of nonoverlapping intervals are mutually independent random variables, and that the number of points in any of these intervals has a Poisson distribution. In this paper we first discuss several general methods for simulation of the one-dimensional non-homogeneous Poisson process; these include time-scale transformation of a homogeneous (rate one) Poisson process via the inverse of the integrated rate function, generation of the individual intervals between points, and generation of a Poisson number of order statistics from a fixed density function. We then state a particular and very efficient method for simulation of nonhomogeneous Poisson processes with log-linear rate function. The method is based on an identity relating the nonhomogeneous Poisson process to the gap statistics from a random number of exponential random variables with suitably chosen parameters. This method can also be used, at the cost of programming complexity and some memory, as the basis for a very efficient technique for simulation of nonhomogeneous Poisson processes with more complicated rate functions such as a log-quadratic rate function. Finally, we describe a simple and relatively efficient new method for simulation of one-dimensional and two-dimensional non-homogeneous Poisson processes. The method is applicable for any given rate function and is based on controlled deletion of points in a Poisson process with a rate function that dominates the given rate function. In its simplest implementation, the method obviates the need for numerical integration of the rate function, for ordering of points, and for generation of Poisson variates. The thinning method is also applicable to the generation of individual intervals between points, as is required in many programs for discrete-event simulations.
Handling of recursion in dataflow model
Authors: S. Ghosh, S. Bandyopadhyay, C. Mazumdar, S. Bhattacharya
Venue: Proceedings of the 1984 annual conference of the ACM on The fifth generation challenge (1984)

Programs for dataflow machines often require efficient support for recursive procedure invocation to achieve high performance and programming flexibility. This paper discusses different methods presently used in contemporary dataflow models for handling recursion. Also, an alternative approach is proposed for handling recursion in token storage type of packet communication dataflow architecture.
A computer simulation of a dental articulator
Authors: Judson Spencer, Michael K. Dever, Merle J. Jaarda, William H. Roedema, John G. Knapp
Venue: Proceedings of the 11th annual symposium on Simulation (1978)

The research described in this paper concerns a model of an articulator, which is itself a mechanical model of the human jaw. These devices have numerous adjustments which allow the user to simulate movement patterns recorded previously from a patient. A mathematical model was devised to duplicate the articulator movement patterns and display the results on a graphics terminal. By varying adjustments in the simulated articulator, the user may observe on the terminal the effects these changes have on the tooth morphology.
On the need for teaching problem-solving in a Computer Science Curriculum
Authors: W. F. Cashman, W. J. Mein
Venue: Proceedings of the fifth SIGCSE technical symposium on Computer science education (1975)

One issue which is not often stressed, or even addressed, in Computer Science Curriculums is that of problem solving. Since problem solving is an essential activity in the construction of programs as well as other computer science pursuits, the omission of any formal instruction in this area is a serious matter. An instructional methodology is proposed for enhancing the problem solving abilities of students enrolled in introductory computer science courses. In particular, a paradigm is proposed to guide the student in his problem solving endeavors. Several examples of problems that were used for the purpose of increasing the students' problem-solving abilities are given.
Representation of process synchronization
Authors: Robert C. Chen
Venue: ACM SIGOPS Operating Systems Review (1975)

There is presently no natural, convenient way to represent synchronization between communicating processes. Two dimensional graph models seem to offer the most natural representations, and of these the Petri net is perhaps the most basic. The author has been working on graph models similar to Petri nets, stressing the ease and convenience of the model as a descriptive device rather than attempting to prove properties such as liveness and safeness. It is shown that Petri nets are incapable of representing some simple and interesting synchronization problems such as reader-writer problems. Recent work has been directed towards the identification of modifications to graph models to overcome such dificiencies.
Simulation of a multiple element test environment
Authors: Kenneth E. Dominiak, Ronald J. Ireland
Venue: Proceedings of the 6th conference on Winter simulation (1973)

A real-time simulation of a multiple element defensive test environment is under study and development. This simulation is to be used for evaluating performance of command and control systems. The initial version of the simulation generates simultaneously up to twenty aircraft each with up to two jamming devices. The overall approach is to generate aircraft tracks and jamming returns at a large scale central digital computer. This data is then transmitted to remote radar sites and converted by on-site equipment to analog signals which are injected into the radar circuitry. A unique feature of the approach is that both real and simulated aircraft will be observed and tracked simultaneously by radar operators.
The CMU design automation system: An example of automated data path design
Authors: A. Parker, D. Thomas, D. Siewiorek, M. Barbacci, L. Hafer, G. Leive, J. Kim
Venue: Proceedings of the 16th Design Automation Conference (1979)

This paper illustrates the methodology of the CMU Design Automation System by presenting an automated design of the PDP-8/E data paths from a functional description. This automated design (using synthesis techniques) is compared both to DEC's implementation and the intersil single chip implementation.
Student program (Paper Session)
Authors: Jose C. Ingojo, Roy Rada, Joe Stiles
Venue: Proceedings of the 1976 annual conference (1976)

The Student Paper Session was created to give students an additional opportunity to participate in the annual ACM conference. The call for papers for the Student Session asked for high quality papers of a theoretical, state-of-the-art or tutorial nature, which had not been previously presented or published. As such, each paper in the Student Session may be of interest to students or professionals. Each paper is to be presented by the author at the conference, and each presented paper will be followed by a period allowing for questions and answers.
Simulation modeling and methodology
Authors: Robert E. Shannon
Venue: Proceedings of the 76 Bicentennial conference on Winter simulation (1976)

Simulation is one of the most powerful analysis tools available to those responsible for the design and/or operation of complex processes or systems. It is heavily based upon computer science, mathematics, probability theory and statistics: yet the process of simulation modeling and experimentation remains very much an intuitive art. Simulation is a very general and somewhat ill-defined subject. For the purpose of this paper, we will define simulation as, &ldquo;the process of designing a computerized model of a system (or process) and conducting experiments with this model for the purpose either of understanding the behavior of the system and/or of evaluating various strategies for the operation of the system.&rdquo; Thus we will understand the process of simulation to include both the construction of the model and the analytical use of the model for studying a problem.
Design aids and hardware testing of microprocessor system circuit packs
Authors: J. Grason
Venue: Proceedings of the Symposium on Design Automation and Microprocessors (1977)

In this paper the hardware testing of microprocessor system circuit packs is treated, with particular emphasis on the role of automatic design aids in this process. Specific problems of implementing these tests on automatic test machines are also considered. Goals and methods of testing in this context are discussed, with special attention paid to functional simulation as a design aid. Several unique problems this type of testing are discussed, including tri-state busses, dynamic RAMs, PROMs, and a poorly testable LSI DIP. Finally the role of design aids and testing in the overall circuit pack development process is discussed.
Mapping HLL constructs into microcode for improved execution speed
Authors: V. Milutinović, D. Roberts, K. Hwang
Venue: ACM SIGMICRO Newsletter (1984)

A processor architecture is presented which enables the constructs typical of HLLs to be mapped into the constructs typical of microcode. This mapping is provided only for selected HLL primitives and HLL statements with a relatively small number of operands and parameters. We are concerned about the optimal hardware/software trade-off, and not about the absolute 1:1 correspondence between HLL statements and highly horizontal microcode. Still, our approach enables the software for time-critical applications to be entirely written in the HLL and executed in the microcode, without the execution-time deteriorations typical for the systems with a large semantic gap between the HLL architecture and the processor architecture. This approach is particularly suitable for the time-critical dedicated control and signal processing. Using an extended subset of Fortran 77, one that matches the typical demands of the specified application area, it is shown that the proposed architecture supports the mapping of HLL constructs into microinstructions. A flexible register-transfer level simulator has been designed and implemented. It was used to run kernel routines on various configurations of the proposed architecture.
A new heuristic test generation algorithm for sequential circuits
Authors: Toshihiro Arima, Mitsukuni Tsuboya, Goro Amamiya, Jiro Okuda
Venue: Proceedings of the 11th Design Automation Workshop (1974)

This paper describes a new heuristic algorithm for the computation of tests to detect failures in sequential logic circuits. In the algorithm, the values of logic blocks in a logic circuit are expressed in boolean vectors with six elements and main process of the algorithm is the operations among these values. Presented in this paper are basic principles for the algorithm, their application procedure with an example and our experiences through the implemented system.
Fault prediction and dynamic error analysis in computer systems
Authors: Roy A. Maxion
Venue: Proceedings of the ACM '81 conference (1981)

Real time monitoring and analysis of computer system performance data can be advantageous in many ways to an industry that spends many billions of dollars each year on computer systems development and service. Traditional approaches to computer system fault diagnosis and repair have a distinctly ex post facto character. From legions of computer service representatives, only a particularly efficacious few seem able to divine accurate clues about failing components by using collections of computer system performance data. Additionally, tracing intermittent problems using this post mortem approach is time and resource intensive and is economically unattractive, especially as installed bases grow and expert technicians become more scarce.
Automated layout in ASHLAR: An approach to the problems of &ldquo;General Cell&rdquo; layout for VLSI
Authors: James E. Hassett
Venue: Proceedings of the 19th Design Automation Conference (1982)

The automated layout facilities of the ASHLAR program, currently under development at the Defense Systems Division of Sperry Univac, are described. ASHLAR is an interactive layout system to be used in developing hierarchical VLSI designs with cells having arbitrary dimensions. Treatment of the problems of placement, power bus routing, and polysilicon interconnect usage are given particular attention. Finally, some results of a prototype implementation are presented.
Pattern driven lazy reduction: A unifying evaluation mechanism for functional and logic programs
Authors: P. A. Subrahmanyam, J-H. You
Venue: Proceedings of the 11th ACM SIGACT-SIGPLAN symposium on Principles of programming languages (1984)

A novel lazy evaluation mechanism, pattern-driven lazy reduction, is developed that serves as a unifying evaluation mechanism for both functional and logic programs. The reduction of a function call can be viewed as &ldquo;semantically&rdquo; unifying the function call with the left hand side of a defining equation, and applying the unifier to the right hand side. Lazy reduction is achieved by the pattern which the function call matches against. Function reductions are actually &ldquo;driven&rdquo; by patterns in this sense. It is shown that this evaluation mechanism works well for both functional programs and logic programs that involve &ldquo;executable&rdquo; functions. As a result, logic programs can be enhanced with (1) the availability of a functional computing environment where there is no notion of backtracking, thus alleviating the degree of control difficulties typically encountered in logic programs, and (2) the ability to terminate &ldquo;infinite computations&rdquo; without the introduction of complex control issues at the user-level. On the other hand, functional programs can be equipped with the power of logic programming languages, e.g., Prolog.
An educational version of a symbol manipulation language
Authors: William E. Kennedy
Venue: Proceedings of the 1975 annual conference (1975)

One important aspect of non-numerical programming has been the development of systems for symbolic mathematics. As an example, Collins' SAC-I package is a powerful, highly portable, and efficient system for symbolic and algebraic computation. General application of these systems, however, has sometimes been hampered because efficiency considerations necessitated limited diagnostic facilities. Hence, users having little experience with such systems often had great difficulty debugging programs. This paper discusses an educational version of the SAC-1 List Processing module, i.e., an implementation which provides extensive error checks, diagnostic messages, and debugging facilities not found in the production version of SAC-1. The implementation has proven very valuable as a learning aid for a broad spectrum of users, from beginning data structures students to high-level applications programmers.