ppxscal/embedding_network huggingface dataset:
Real-time threads
Authors: Karsten Schwan, Hongyi Zhou, Ahmed Gheith
Venue: ACM SIGOPS Operating Systems Review (1991)

Portability is an important attribute of real-time operating systems because their target hardware environments routinely vary from special purpose processors to parallel machines to distributed execution environments. In this paper, we address the issue of operating systems portability by development of a real-time threads package based on the Mach cthreads interface. Real-time threads have been implemented on standard Unix platforms and on a 32-node BBN Butterfly multiprocessor. In contrast to cthreads, the schedulability of real-time threads may be determined dynamically at the time of threads creation. In addition, any scheduling guarantees made at thread creation time are maintained when threads communicate or cooperate using the package's other primitives.
A0 system: APL in construction planning
Authors: Alexei I. Miroshnikov
Venue: Proceedings of the international conference on APL '91 (1991)

This paper describes an automation system for construction planning, named A0. A0 was developed for usage by big building companies at various stages of preparing and executing construction works. It supports different tasks starting with calculation of project estimates, bills of materials, and schedules of works and ending by providing the company executives with complete information for the supervision of the building process in their company. A0 includes also a DBMS for the All Union Data Base on Construction. The amount of data in the data base is about 45MB for the Leningrad region only. At present the system is used by the Leningrad Building Corporation.A0 is all written in APL #9733;PLUS/PC. The system will be distributed with the run-time system of APL #9733;PLUS for the Soviet customers just after the performance test. The A0 system was developed in market competition with six similar projects using different programming systems: FoxBase, Clipper, Turbo-Pascal, and the MS C-compiler. The advantages of the system under consideration were, in many ways, ensured by choosing APL. Some advantages and disadvantages of using APL for that kind of application system are discussed in the paper as well.
Relating psychology's moral development levels to the ethical use of computers (abstract)
Authors: Riva Wenig Bickel, Maria Larrondo Petrie
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

A disturbing increase in computer related crime highlights the lack of methodologies for promoting ethical computer use. Our research addresses this issue by developing an evaluation tool for determining ethical levels vis-a-vis computers. Educational methodologies are being developed which will be evaluated by this tool. The instrument, based on scenarios involving Kohlberg style ethical dilemmas pertaining to computers, is modeled after Rest's Defining Issues Test. A pilot presentation of the scenarios to 18 computer students revealed interesting information about student attitudes. Students reacted to each of eight scenarios, explaining their reasoning in writing. After extended class debate, they reanalyzed the scenarios, ranking factors by degree of influence and stating whether the discussion changed their opinions.
The agent network architecture (ANA)
Authors: Pattie Maes
Venue: ACM SIGART Bulletin (1991)

The goal of my work is to develop and implement an architecture for an autonomous agent, which I refer to as "ANA". An ANA agent consists of a distributed set of "competence modules". Competence modules are linked in a network. A spreading activation process operates on the network to decide what the "relevance" or relative strength of a competence module is in the current context. This process implements a competition among modules for activation energy. The higher the activation energy level of a module, the more likely it is that this module determines what the autonomous agent does or communicates to believe. Learning is a central, completely integrated feature of the architecture. The competence module network is continuously being developed and changed on the basis of experience: links are added and deleted depending on real world observations and new "macro modules" are created whenever a goal is achieved. This paper presents an overview of the architecture. It describes the functionalities that have been implemented, the results that have been obtained with robotic and simulated ANA agents, and finally it discusses (current) limitations and future work.
Sequential Diagnosability is Co-NP Complete
Authors: Vijay Raghavan, Anand Tripathi
Venue: IEEE Transactions on Computers (1991)

F.P. Preparata et al. (1967) introduced a graph-theoretical model for fault diagnosis called the PMC model. The question of determining the sequential diagnosability number of a system in the PMC model has remained open. The authors formalize the notion of sequential diagnosability. The question of determining the sequential diagnosability number of a system is addressed by showing that the appropriate decision problem is co-NP complete. The problem is also shown to be co-NP complete even when restricted to planar graphs both in the weighted and the BGM models.
Converting nested algebra expressions into flat algebra expressions
Authors: Jan Paredaens, Dirk Van Gucht
Venue: ACM Transactions on Database Systems (TODS) (1992)

Nested relations generalize ordinary flat relations by allowing tuple values to be either atomic or set valued. The nested algebra is a generalization of the flat relational algebra to manipulate nested relations. In this paper we study the expressive power of the nested algebra relative to its operation on flat relational databases. We show that the flat relational algebra is rich enough to extract the same &ldquo;flat information&rdquo; from a flat database as the nested algebra does. Theoretically, this result implies that recursive queries such as the transitive closure of a binary relation cannot be expressed in the nested algebra. Practically, this result is relevant to (flat) relational query optimization.
What every computer scientist should know about floating-point arithmetic
Authors: David Goldberg
Venue: ACM Computing Surveys (CSUR) (1991)

Floating-point arithmetic is considered as esoteric subject by many people. This is rather surprising, because floating-point is ubiquitous in computer systems: Almost every language has a floating-point datatype; computers from PCs to supercomputers have floating-point accelerators; most compilers will be called upon to compile floating-point algorithms from time to time; and virtually every operating system must respond to floating-point exceptions such as overflow. This paper presents a tutorial on the aspects of floating-point that have a direct impact on designers of computer systems. It begins with background on floating-point representation and rounding error, continues with a discussion of the IEEE floating point standard, and concludes with examples of how computer system builders can better support floating point.
Application of symbolic computation in robot pose error modelling
Authors: Naren Vira, Tepper Gill, Edward Tunstel
Venue: Journal of Symbolic Computation (1990)

This paper presents an application of symbolic computation in geometrical error modelling and simulation of an industrial robotic manipulator. A program named SCRPE (Symbolic Computation of Robot Pose Errors) has been developed to automatically generate error model equations for the end-eflector of N degree-of-freedom robots. The SCRPE utilizes symbolic manipulation capability of MACSYMA (a Lisp-base artificial intelligence language). The prime reasons of this work are to provide a base for comparison, performance assessment and accuracy judgment of numerous error calibration and compensation models available in the literature; and to represent output results in a concise form eliminating completely the manual derivation process. When such computer generated outputs are fed to a simulation program, saving in computational time for error estimation is realized. As an example, the mathematical error model considered here is based on small perturbation in link parameters defined in accordance with a classical Denavit-Hartenberg notation. The time required to compute first and second order terms of the model are compared for numerous robots. The worst case scenario takes 290 seconds for a PUMA 600 series robot, which is insignificant compared to the time required for accurate manual derivation. The SCRPE program is user-friendly, interactively menu-driven and has been developed on VAX 750 Digital computer under the VMS operating system. Interested readers can obtain the program copy by contacting the first author.
On Navigating Between Friends and Foes
Authors: N. Kiryati, A. M. Bruckstein
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

The problem of determining the optimal straight path between a planar set of points is considered. Each point contributes to the cost of a path a value that depends on the distance between the path and the point. The cost function, quantifying this dependence, can be arbitrary and may be different for different points. An algorithm to solve this problem using an extension of the Hough transform is described. The range of applications includes straight-line fitting to a set of points in the presence of outliers, navigation, and path planning. The proposed extended Hough transform can be tuned to equivalent to well-known robust least-squares techniques, and allows efficient, approximate M-estimation.
Designing interactive visualization tools for the graphics classroom
Authors: D. Schweitzer
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

Student comprehension of the concepts and algorithms in computer graphics requires a thorough visual understanding of the processes involved. To assist this understanding in the computer graphics course at the Air Force Academy, a set of interactive visualization programs were created for classroom use. These programs demonstrate key graphic concepts using various visual metaphors. The process of creating and using these tools in the classroom highlighted several design guidelines when creating classroom visualization tools. This paper describes these design guidelines, and the way in which the tools are used in the classroom to support lecture material. The paper concludes with our experience using these tools and future plans.
Comparison of sparing alternatives for disk arrays
Authors: Jai Menon, Dick Mattson
Venue: Proceedings of the 19th annual international symposium on Computer architecture (1992)

This paper explores how choice of sparing methods impacts the performance of RAID level 5 (or parity striped) disk arrays. The three sparing methods examined are dedicated sparing, distributed sparing, and parity sparing. For database type workloads with random single block reads and writes, array performance is compared in four different modes - normal mode (no disks have failed), degraded mode (a disk has failed and its data has not been reconstructed), rebuild mode (a disk has failed and its data is being reconstructed), and copyback mode(which is needed for distributed sparing and parity sparing when failed disks are replaced with new disks). Attention is concentrated on small disk subsystems (fewer than 32 disks) where choice of sparing method has significant impact on array performance, rather than large disk subsystems (64 or more disks). It is concluded that, for disk subsystems with a small number of disks, distributed sparing offers major advantages over dedicated sparing in normal, degraded and rebuild modes of operation, even if one has to pay a copyback penalty. Furthermore, it is better than parity sparing in rebuild mode and similar to it in other operating modes, making it the sparing method of choice.
Proceedings of the workshop on Speech and Natural Language
Venue: Human Language Technology Conference (1989)

The first DARPA-sponsored Speech and Natural Language Workshop took place in Philadelphia, Pennsylvania, on 21-23 February 1989. The workshop dealt with all aspects of the DARPA speech and natural language programs, placing special emphasis on spoken language understanding. It was the first time that representatives of all the DARPA-sponsored groups met together, and a special effort was made to cross-educate the two communities.The workshop was quite successful along a number of dimensions. Over 120 people participated. In addition to the DARPA contractors, representatives of AT&T and IBM attended, making important contributions. Much progress was reported, many new ideas were surfaced, and a great deal of cross-fertilization occurred both in and outside the sessions. It was especially encouraging to see the speech and natural language communities talking to one another.This Proceedings begins with an overview of the workshop, a copy of the agenda, summaries of the various sessions by their respective chairs, and two tutorial papers. The bulk of the Proceedings consists of many of the technical papers presented during the workshop. (Papers being published elsewhere are not included.) A brief summary of each contractor's program appears before the papers from that contractor. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
An overview of GOOD
Authors: Jan Paredaens, Jan Van den Bussche, Marc Andries, Marc Gemis, Marc Gyssens, Inge Thyssens, Dirk Van Gucht, Vijay Sarathy, Lawrence Saxton
Venue: ACM SIGMOD Record (1992)

GOOD is an acronym, standing for Graph-Oriented Object Database. GOOD is being developed as a joint research effort of Indiana University and the University of Antwerp. The main thrust behind the project is to indicate general concepts that are fundamental to any graph-oriented database user-interface. GOOD does not restrict its attention to well-considered topics such as ad-hoc query facilities, but wants to cover the full spectrum of database manipulations. The idea of graph-pattern matching as a uniform object manipulation primitive offers a uniform framework in which this can be accomplished.
Real theorem provers deserve real user-interfaces
Authors: Laurent Théry, Yves Bertot, Gilles Kahn
Venue: ACM SIGSOFT Software Engineering Notes (1992)

This paper explains how to add a modern user interface to existing theorem provers, using principles and tools designed for programming environments.
Automated Software Test Data Generation
Authors: B. Korel
Venue: IEEE Transactions on Software Engineering (1990)

An alternative approach to test-data generation based on actual execution of the program under test, function-minimization methods and dynamic data-flow analysis is presented. Test data are developed for the program using actual values of input variables. When the program is executed, the program execution flow is monitored. If during program execution an undesirable execution flow is observed then function-minimization search algorithms are used to automatically locate the values of input variables for which the selected path is traversed. In addition, dynamic data-flow analysis is used to determine those input variables responsible for the undesirable program behavior, significantly increasing the speed of the search process. The approach to generating test data is then extended to programs with dynamic data structures and a search method based on dynamic data-flow analysis and backtracking is presented. In the approach described, values of array indexes and pointers are known at each step of program execution; this information is used to overcome difficulties of array and pointer handling.
Design and simulation of opera lighting and projection effects
Authors: Julie O'B. Dorsey, Françis X. Sillion, Donald P. Greenberg
Venue: Proceedings of the 18th annual conference on Computer graphics and interactive techniques (1991)

A major problem challenging opera designers is the inability to co-ordinate lighting, projection systems, and set designs in the preliminary planning phase. New computer graphics techniques, which provide the set and lighting designer the opportunity to evaluate, test, and control opera designs prior to the construction of full scale systems are presented. These techniques---light source input, simulation of directional lighting, modeling of scenic projection systems, and full three-dimensional simulation---show the potential for the use of computer graphics in theater design.The light source input component consists of a program for assigning light source attributes with a set of theater lighting icons. This module allows a designer to specify light source characteristics in a way familiar to the discipline and to make preliminary evaluations of the lighting conditions.An extended progressive radiosity method is introduced to simulate the directional lighting characteristics which are specified by the input program.A new projection approach is presented to simulate the optical effects of scenic projectors. In addition, a solution to the distortion problem produced by angular projections is described.The above components are integrated to produce full three-dimensional simulations of the global illumination effects in an opera scene.
Teaching operating systems using Turbo C
Authors: Larry Hughes
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

Operating systems are an example of a subject that, given the right tools, can be taught in a practical manner, allowing students to understand, and hence appreciate, the internal workings of commercial operating systems such as VMS, Unix, or VM. Not surprisingly, the tools needed in an operating systems course are, at a minimum, a hardware testbed and a programming language into which algorithms can be translated. This paper describes how many of the salient points concerning operating systems can be covered in a practical manner using the PC and Turbo C.
Base-value in actuarial practice
Authors: Jan Karman
Venue: ACM SIGAPL APL Quote Quad (1991)

In this paper, only one APL primitive is involved: decode ( perp;). Decode (or base-value) gives us the evaluation of a polynomial. The life annuity, which is of crucial importance in actuarial practice, is a polynomial, and it is plausible that the APL primitive decode is very useful in this respect.The paper starts with an introduction in the fundamentals of mortality tables, continues with the derivation of the life annuity and finally comes to an extremely powerful use of the base-value primitive.It is emphasized that the actuarial theory in general is applicable to any kind of large population, whether consisting of light bulbs, refrigerators, television sets, motor cars, or books in a library [1]. For instance, replacement of consumer durables in case of break-down within a guarantee period is a term insurance.Further, a term insurance, as almost any contract of life insurance, can be expressed as a function of a life annuity.
Compiler structure engineering with attribute grammars
Authors: Ilka Miloucheva, Hans Loeper
Venue: ACM SIGPLAN Notices (1991)

In this paper are discussed the concepts of a compiler structure design system and its prototype implementation.In order to obtain the pass structure based on the properties of the deterministic left to right evaluable attribute grammars we use short path algorithms for directed graphs. An algorithm for assignment of attributes to separate passes is shown. We propose a method for extension of the deterministic left to right evaluable attribute grammars with global data. Futher we describe the approach of a syntax oriented modularization for specifying the compiler structure.Using this research as a base we developed the CSD system (Compiler Structure Design). The CSD system is a compiler engineering tool providing facilities for specification of compilers and for design of their pass, intermediate program and module structure. The main components of the system are also shown and its use for development of a COBOL compiler are discussed.
How to program in Ada 9X, using Ada 83
Authors: Erhard Ploedereder
Venue: ACM SIGAda Ada Letters (1992)

Existing software will have to be transitioned from Ada 83 to Ada 9X. This paper explains presently known incompatibilities between the existing Ada standard and its proposed revision. It provides guidelines to users, which will make their Ada 83 code upward compatible with Ada 9X.
Hector: A Hierarchically Structured Shared-Memory Multiprocessor
Authors: Zvonko G. Vranesic, Michael Stumm, David M. Lewis, Ron White
Venue: Computer (1991)

The architecture of the Hector multiprocessor, which exploits current microprocessor technology to produce a machine with a good cost/performance tradeoff, is described. A key design feature of Hector is its interconnection backplane, which can accommodate future technology because it uses simple hardware with short critical paths in logic circuits and short lines in the interconnection network. The system is reliable and flexible and can be realized at a relatively low cost. The hierarchical structure results in a fast backplane and a bandwidth that increases linearly with the number of processors. Hector scales efficiently to larger sizes and faster processors.
MDM: an object-oriented data model
Authors: Joel Richardson, Peter Schwarz
Venue: Proceedings of the third international workshop on Database programming languages : bulk types persistent data: bulk types persistent data (1992)

This paper describes MDM, an object-oriented data model that supports instance-level evolution and associative queries. The MDM type system, based on abstract types and conformity, allows flexibility in defining applications and interacts well with the query facility. The query algebra consists of a small set of simple operators; many other useful operators can be defined through composition. MDM defines only a primitive notion of object equivalence, although the algebra includes an operator that allows user-defined equivalence relations to direct the grouping of objects in a multiset.
Use of computer algebra to locate critical loci in fluid mixtures
Authors: Glen C. Nielson, Mark O. Mclinden, Graham Morrison
Venue: Journal of Symbolic Computation (1990)

This paper describes the use of computer algebra to find critical points in 2-component fluid mixtures. We describe the application of the method to a problem which has been studied by traditional methods. Our results for this case are, happily, identical to earlier work. We apply the method to systems described by the Carnahan-Starling-DeSantis equation and present results for refrigerant mixtures described by this equation.
The Epilog System-Automated Long-Term EEG Monitoring for Epilepsy
Authors: Thomas F. Collura, Ernest C. Jacobs, Richard C. Burgess, John P. Turnbull
Venue: Computer (1992)

Epilog, a Unix-based real-time operational support system for electroencephalogram (EEG) waveform acquisition, storage, analysis, display, and printing, is described. The system is designed to be used for diagnosis and surgical planning in a large epilepsy program. The implemented system has two monitoring units consisting of four rooms with their associated computer, video, and medical support systems. A central computer hub performs Epilog services for each unit. Each hub acquires and processes up to 256 channels of EEG 24 h per day, and serves as a control center for much of the automation in the unit. The EEG data structures and data flow used in Epilog are discussed.