ppxscal/embedding_network huggingface dataset:
Computer-support cooperative work
Authors: Jakob Nielsen
Venue: ACM SIGCHI Bulletin (1987)

At CHI'86 it was a general impression that the area of several people working together using computers was starting to become the next hot topic as a research area. At the same time the European Community is considering changing the focus of the human factors part of the next ESPRIT research program from the so-called human factors-1 (interaction between a single human and a single computer) to human factors-2 (interaction between several humans and several computers).
An object-oriented design system shell
Authors: Jim Diederich, Jack Milton
Venue: Conference proceedings on Object-oriented programming systems, languages and applications (1987)

We present a design system shell which can be used to experiment with principles of design and be used as a design tool where complex layers of information need to be specified about objects, such as in database design. The shell can be tailored to a variety of application areas. It is object-oriented in its implementation and structure. Objects and messages are used as the specification language. The basic ingredients of a rule-based production system are provided, with rules treated as objects and defined independently of the classes to which they are applied.
Portability and the UNIX operating system
Authors: Daniel A. Cañas, Laura M. Esquivel
Venue: ACM SIGOPS Operating Systems Review (1988)

This paper studies the compatibility degree between two different UNIX2 environments. The porting of ConcurrenC (concurrent version of the C programming language) from a VAX3 computer under UNIX 4.2BSD to an AT amp;T UNIX PC running UNIX System V was used as a testbed.ConcurrenC is analyzed to highlight the existence of the 4.2BSD features missing in UNIX System V. These characteristics are mainly related to system calls used for interrupt handling, and for process synchronization and communication. They are implemented under System V using new provided facilities (i.e., message mechanism for interprocess communication), or simulating their functioning through special purpose C language routines.
Boolean operations of 2-manifolds through vertex neighborhood classification
Authors: Martti Mäntylä
Venue: ACM Transactions on Graphics (TOG) (1986)

A topologically complete set operations algorithm for planar polyhedral Z-manifold objects is described; that is, under the assumption that all numerical tests required can be correctly evaluated, the algorithm is capable of solving all &ldquo;special cases." The central component of the algorithm is a module here called the vertex neighborhood classifier. By virtue of the classifier, the various special cases can be reduced into a collection of classification problems involving a pair of coincident vertices. The classifier works by means of decision rules that guarantee the topological consistency and regularity of the resulting polyhedron. If the result is not a 2-manifold, a relaxed polyhedron will be produced.
Software design synthesis for strategic computing
Authors: C. G. Davis
Venue: Proceedings of the 1987 Fall Joint Computer Conference on Exploring technology: today and tomorrow (1987)

The design process for large military systems is an extremely complex undertaking. The size of these systems, coupled with the high cost of making mistakes in their design makes their implementation a matter of national concern. Since these systems are typically controlled by computers, the ability of software technology to support these complex developments has repeatedly come into question. One particular class, Strategic Defense Systems, has been predominantly in the spotlight these past few years. The &ldquo;Software for Strategic Systems Conference&rdquo; was held on May 14, 15, 1987 in Huntsville, Alabama. The conference had over 250 in attendance and addressed in a positive vein issues relating to developing software for these complex strategic systems. Specific issues that were addressed at the conference regarding the development of software for strategic systems included: The potential for Artificial Intelligence in strategic systems The promise that software development technology has for Strategic Applications The potential for the national software initiatives to transfer technology applicable to strategic defense Specific software development needs for the Strategic Defense Initiative Testing and Testbeds for strategic defense Each of these issues was addressed in depth with views of the speakers reflecting widely differing opinions. These areas will be addressed in this panel session. Each of the panelists were involved and participated in the conference. The following pages reflect the positions of the individual panelists.
A logic programming model of the game of sprouts
Authors: Ralph M. Butler, Selden Y. Trimble, Ralph W. Wilkerson
Venue: ACM SIGCSE Bulletin (1987)

The game of Sprouts has intrigued mathematicians for nearly twenty years. This paper describes a representation scheme which simplifies much of the geometry of the game. Using this representation, we develop a Prolog program which will play Sprouts. It is hoped that the program will prove to be a useful research tool in finding the key to a winning strategy for Sprouts and that the representation will serve as a useful model for studying planar graphs.
Self-organizing linear search
Authors: J. H. Hester, D. S. Hirschberg
Venue: ACM Computing Surveys (CSUR) (1985)

Algorithms that modify the order of linear search lists are surveyed. First the problem, including assumptions and restrictions, is defined. Next a summary of analysis techniques and measurements that apply to these algorithms is given. The main portion of the survey presents algorithms in the literature with absolute analyses when available. The following section gives relative measures that are applied between two or more algorithms. The final section presents open questions.
Testable Realizations for FET Stuck-Open Faults in CMOS Combinational Logic Circuits
Authors: Sudhakar M. Reddy, Madhukar K. Reddy
Venue: IEEE Transactions on Computers (1986)

In this paper, potential invalidation of stuck-open fault-detecting tests, derived by neglecting circuit delays and charge distribution in CMOS logic circuits, is studied. Several classes of circuits derived from sum of products and product of sums expressions for a given combinational logic function are investigated to determine the testability of FET stuck-open faults by tests which will remain valid in the presence of arbitrary circuit delays. Necessary and sufficient conditions for the existence of tests that will remain valid in the presence of arbitrary circuit delays are derived. Using these conditions, it is shown that all single FET stuck-open faults, in a specific design using a single CMOs complex gate, are detectable by tests that remain valid in the presence of arbitrary circuit delays. For several other realizations, methods to augment them, to insure detectability of all single FET stuck-open faults by tests that will remain valid in the presence of arbitrary circuit delays are proposed. It is observed that in many of the logic circuits investigated it is also possible to avoid test invalidation due to charge distribution.
Notes on conceptual representations
Authors: E Knuth, L Hannak, A Hernadi
Venue: Proceedings of the ACM SIGART international symposium on Methodologies for intelligent systems (1986)

Underlying concepts of &ldquo;conceptual modelling&rdquo; are examined. A systematic layered approach is presented in order to improve techniques recently used.
Retrofitting objects
Authors: Robert E. Filman
Venue: ACM SIGPLAN Notices (1987)

I present the results of an experiment in retrofitting objects into an existing system. I describe a technology, based on automatic redefinition of existing functions, that allowed alternative implementations of the fundamental data types of the KEE&trade; knowledge-based system building tool. This technology is applicable in environments where the system's procedures can be subject to programmatic manipulation. It allows the retrofitting of objects into the implementations of other existing systems. The experience of retrofitting objects into KEE provides insight into the issues of the interaction of semantic classes and data representation and granularity in object-based systems.1
Compiling LISP procedures
Authors: Bruce A Pumplin
Venue: ACM SIGSMALL/PC Notes (1987)

The programming language LISP is frequently the language of choice for the implementation of artificial intelligence (AI) systems, even though it has earned a reputation for being slow. This lack of speed is usually due to the fact that commonly available LISP implementations are interpretive in nature rather than compile and go. And we all know that interpreting source code is invariably slower than simply executing the compiled object code.
The rotation group of Rubik's cube
Authors: O. Knill, R. E. Mäder
Venue: ACM SIGSAM Bulletin (1987)

In this project, the group theory program "Cayley" is used to solve some problems associated with Rubik's Cube, including the original problem of restoring the initial state of the cube.
The application of scene synthesis techniques to the display of multidimensional image data
Authors: Philip K. Robertson, John F. O'Callaghan
Venue: ACM Transactions on Graphics (TOG) (1985)

Superimposition of two image data sets allows the spatial distribution of one to be directly related to that of the other. If the two data sets have different spatial structures, the composite image is generally confusing and difficult to interpret. A method of representing image data sets in the form of naturally occurring variables in a realistic apparently three-dimensional scene is presented. One data set is represented by the topography of a surface, depicted by shaded-relief methods, while another is represented by the color of the surface, or by the color of an overlaid transparency. Presentation in this form exploits the normal scene decomposition abilities of the human visual system, allowing intuitive appreciation and separation of the scene, and hence data set, variables. The method relies on techniques for the modeling of surfaces and surface reflectance to render the synthesised scenes realistically.
Test Length for Pseudorandom Testing
Authors: C. K. Chin, E. J. McCluskey
Venue: IEEE Transactions on Computers (1987)

The process of determining the required test length for a desired level of confidence for pseudorandom testing using a random sampling without replacement model is examined. The differences between random and pseudorandom testing are discussed and developed. The strictly random testing model is shown to be inaccurate for high confidence testing of combinational circuits. A method of calculating the required test length for pseudorandom testing based upon fault detectabilities is described. The result provides a very accurate prediction of required test length applicable to self-test using pseudorandom inputs.
A management system for monitoring and assessing the group-oriented database project
Authors: D. V. Pigford
Venue: ACM SIGCSE Bulletin (1987)

This paper presents the evaluation techniques and forms for implementing group-oriented database projects in a senior level database course. A management system for monitoring the design, implementation, and testing of a small production database application using the team approach serves as the focus of this paper. Emphasis is upon both time and efficiency for students and instructor. The database prototype is implemented in phase one with a relational microcomputer tool and in phase two with a relational mainframe DBMS.
HPSm, a high performance restricted data flow architecture having minimal functionality
Authors: W. Hwu, Y. N. Patt
Venue: Proceedings of the 13th annual international symposium on Computer architecture (1986)

Our recent work in microarchitecture has identified a new model of execution, restricted data flow, in which data flow techniques are used to coordinate out-of-order execution of sequential instruction streams. We believe that the restricted data flow model has great potential for implementing very high performance computing engines. This paper defines a minimal functionality variant of our model, which we are calling HPSm. The instruction set, data path, timing and control of HPSm are all described. A simulator for HPSm has been written, and some of the Berkeley RISC benchmarks have been executed on the simulator. We report the measurements obtained from these benchmarks, along with the measurements obtained for the Berkeley RISC II. The results are encouraging.
Fuzzy Concepts in Expert Systems
Authors: K. S. Leung, W. Lam
Venue: Computer (1988)

The authors present a comprehensive expert-system building tool, called System Z-II, that can deal with exact, fuzzy (or inexact), and combined reasoning, allowing fuzzy and normal terms to be freely mixed in the rules and facts of an expert system. This fully implemented tool has been used to build several expert systems in the fields of student curriculum advisement, medical diagnosis, psychoanalysis, and risk analysis. System Z-II is a rule-based system that uses fuzzy logic and fuzzy numbers for its inexact reasoning. It uses two basic inexact concepts, fuzziness and uncertainty, which are distinct from each other in the system.
The existence and density of generalized complexity cores
Authors: Ronald V. Book, Ding-Zhu Du
Venue: Journal of the ACM (JACM) (1987)

If C is a class of sets and A is not in C, then an infinite set H is a proper hard core for A with respect to C, if H &sube; A and for every C &egr; C such that C &sube; A, C &Cap; H is finite. It is shown that if C is a countable class of sets of strings that is closed under finite union and finite variation, then every infinite set not in C has a proper hard core with respect to C. In addition, the density of such generalized complexity cores is studied.
Optimal prepaging and font caching
Authors: David R. Fuchs, Donald E. Knuth
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1985)

An efficient algorithm for communicating letter-shape information from a high-speed computer with a large memory to a typesetting device that has a limited memory is presented. The encoding is optimum, in the sense that the total time for typesetting is minimized, using a model that generalizes well-known &ldquo;demand paging&rdquo; strategies to the case where changes to the cache are allowed before the associated information is actually needed. Extensive empirical data show that good results are obtained even when difficult technical material is being typeset on a machine that can store information concerning only 100 characters. The methods of this paper are also applicable to other hardware and software caching applications with restricted lookahead.
A prototype system for the electronic storage and retrieval of document images
Authors: G. R. Thoma, S. Suthasinekul, F. L. Walker, J. Cookson, M. Rashidian
Venue: ACM Transactions on Information Systems (TOIS) (1985)

A prototype system has been implemented for electronic scanning, digitization, storage, retrieval, and display of images of biomedical documents. Paper documents are scanned and digitized at a scan density of 200 picture elements (pels) per inch by either a high-speed loose-leaf scanner with an automatic document transport or a book scanner with a manual book holder. Each scanner employs a high-resolution charge-coupled device (CCD) linear array operating at a sampling rate close to 10 MHz. The analog output signal of the CCD array is digitized into 1 bit per pixel two-tone images by means of dynamic thresholding. The digitized images are stored on magnetic disks to be processed and will eventually be transferred onto optical disks for archival storage. Existing on-line bibliographic databases developed by the National Library of Medicine are used as directories for the retrieval of document images. These images are displayed at a resolution of 200 pels/inch in both soft-copy (raster-refreshed CRT) and hard-copy forms. This prototype system, developed as part of a research and development program, offers the opportunity to investigate the areas of document image enhancement, image compression, and omnifont text recognition and to conduct experiments designed to answer key questions on the role of electronic document storage and retrieval technology in library information processing and the preservation of library documents.
Expert system on a chip: an engine for real-time approximate reasoning
Authors: M Togai, H Watanabe
Venue: Proceedings of the ACM SIGART international symposium on Methodologies for intelligent systems (1986)

The role of inferencing with uncertainty is becoming more important in rule-based expert systems (ES), since knowledge given by a human expert is often uncertain or imprecise. We have succeeded in designing a VLSI chip which can perform an entire inference process based on fuzzy logic. The design of the VLSI fuzzy inference engine emphasizes simplicity, extensibility, and efficiency (operational speed and layout area). It is fabricated in 2.5 &mgr;m CMOS technology. The inference engine consists of three major components; a rule set memory, an inference processor, and a controller. In this implementation, a rule set memory is realized by a read only memory (ROM). The controller consists of two counters. In the inference processor, one data path is laid out for each rule. The number of the inference rule can be increased adding more data paths to the inference processor. All rules are executed in parallel, but each rule is processed serially. The logical structure of fuzzy inference proposed in the current paper maps nicely onto the VLSI structure. A two-phase nonoverlapping clocking scheme is used. Timing tests indicate that the inference engine can operate at approximately 20.8 MHz. This translates to an execution speed of approximately 80,000 Fuzzy Logical Inferences Per Second (FLIPS), and indicates that the inference engine is suitable for a demanding real-time application. The potential applications include decision-making in the area of command and control for intelligent robot systems, process control, missile and aircraft guidance, and other high performance machines.
Properties that characterize LOGCFL
Authors: H. Venkateswaran
Venue: Proceedings of the nineteenth annual ACM symposium on Theory of computing (1987)

Two properties, called semi-unboundedness, and polynomial proof-size, are identified as key properties shared by the definitions of LOGCFL on several models of computations. The semi-unboundedness property leads to the definition of new models of computation based on unbounded fan-in circuits. These are circuits obtained from unbounded fan-in circuits by restricting the fan-in of gates of one type. A new characterization of LOGCFL is obtained on such a model in which the fan-in of the AND gates are bounded by a constant. This property also suggests new characterizations of LOGCFL on the following models: alternating Turing machines [CKS81], nondeterministic auxiliary pushdown automata [Co71], and bounded fan-in Boolean circuits [Co85].
Use of instruction set simulators to evaluate the LOW RISC
Authors: Brian Short
Venue: ACM SIGARCH Computer Architecture News (1987)

The LOW RISC has been proposed as an HLL architecture for Prolog. This paper describes the development and use of software simulators for evaluation of the LOW RISC instruction set.
Comparing how atomicity mechanisms support replication
Authors: Maurice Herlihy
Venue: ACM SIGOPS Operating Systems Review (1986)

Most pessimistic mechanisms for implementing atomicity in distributed systems fall into three broad categories: two-phase locking schemes, timestamping schemes, and hybrid schemes employing both locking and timestamps. This paper proposes a new criterion for evaluating these mechanisms: the constraints they impose on the availability of replicated data.A replicated data item is a typed object that provides a set of operations to its clients. A quorum for an operation is any set of sites whose co-operation suffices to execute that operation, and a quorum assignment associates a set of quorums with each operation. Constraints on quorum assignment determine the range of availability properties realizable by a replication method.This paper compares the constraints on quorum assignment necessary to maximize concurrency under generalized locking, timestamping, and hybrid concurrency control mechanisms. This comparison shows that hybrid schemes impose weaker constraints on availability than timestamping schemes, and locking schemes impose constraints incomparable to those of the others. Because hybrid schemes permit more concurrency than locking schemes, these results suggest that hybrid schemes are preferable to the others for ensuring atomicity in highly available and highly concurrent distributed systems.This research was sponsored by the Defense Advanced Research Projects Agecy (DOD), ARPA Order No. 3597, monitored by the Air Force Avionics Laboratory Under Contract F33615-81-K-1539.The views and conclusions contained in this document are those of the authords and should not be interpreted as representing the official policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the US Government.
A first course in programming
Authors: Doug Bell, Peter Scott
Venue: ACM SIGCSE Bulletin (1987)

Many of us have grappled with the design of a first course in programming - what language to use, how to sequence topics, how to encourage practical experience, how to assess. This paper explains the rationale behind a course that has matured over several years, and that we feel is sucessful.
A mechanical proof of the Church-Rosser theorem
Authors: N. Shankar
Venue: Journal of the ACM (JACM) (1988)

The Church-Rosser theorem is a celebrated metamathematical result on the lambda calculus. We describe a formalization and proof of the Church-Rosser theorem that was carried out with the Boyer-Moore theorem prover. The proof presented in this paper is based on that of Tait and Martin-L&ouml;f. The mechanical proof illustrates the effective use of the Boyer-Moore theorem prover in proof checking difficult metamathematical proofs.
Cobol and the information systems curriculum
Authors: George P Schell
Venue: ACM SIGCPR Computer Personnel (1986)

There is considerable disagreement as to whether or not a procedural language, such as COBOL, should be included in the junior/senior year course work of information systems students. The curriculum recommendations of the Association for Computing Machinery (ACM) includes a procedural language prerequisite for information systems students. The ACM curriculum course, "Program, Data, and File Structures", includes programming as a topic within the course.This article presents arguments against the inclusion of COBOL within the information systems curriculum. It is intended to promote debate within the academic community to determine if a procedural language should be included in the curriculum and if so, which language should be taught. Arguments for a Procedural Language.
Social choice theory and distributed decision making
Authors: Arnold B. Urken
Venue: Proceedings of the ACM SIGOIS and IEEECS TC-OA 1988 conference on Office information systems (1988)

Strategies of distributed decision making based on social choice theory can be used to create a balance between organizational complexity and uncertainty. Although Group Decision Support Systems (GDSS's) have included options for making human collective choices, their design has not been based on optimal rules. Social choice theory can also be used to improve the reliability of decisions made by nodes in distributed computer networks. Three examples illustrate the application of this theory: human computer-mediated distributed decision making, electing a coordinator to reorganize a failed distributed network, and using weighted votes to improve network reliability.