ppxscal/embedding_network huggingface dataset:
A real introduction to supercomputing: a user training course
Authors: Floyd B. Hanson
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

An introductory graduate course on supercomputing for computer science, applied science, and engineering majors is described. The interests of the students cover a broad range, from training as engineering or scientific supercomputer users to computer scientists interested in algorithmic, architectural, and statistical issues. An essential feature of this course is the use of real supercomputer time on several machines of advanced architecture. Remote supercomputer access is obtained from the national supercomputing centers. The students do several small group research projects on supercomputers, concerning performance, algorithm design and applications. A number of techniques are used to enhance the learning environment, such as local user guides, preparation for access difficulties, and appropriate beginning problems.
GRIN: The History of a Laboratory
Authors: C. Pair
Venue: IEEE Annals of the History of Computing (1990)

Together with Grenoble, Paris, Toulouse, and Nantes, Nancy was one of the first French universities in which computer science appeared 30 years ago. The history of computer science in each French university has its own particular character. Through such a history (1960-1975) one can understand a certain number of general phenomena.
Uses Made of Computer Algebra in Physics
Authors: H. I. Cohen, J. P. Fitch
Venue: Journal of Symbolic Computation (1991)

Computer algebra is a tool building activity. This paper is a review of acceptance of this tool by physicists and theoretical chemists during the period from the EUROSAM-79 survey to the Spring of 1988, as reflected by the literature which quotes computer algebra. After considering the traditional areas of application; celestial mechanics, relativity and quantum mechanics, we extend our examination to other areas of physics which would appear, from the literature, to be using computer algebra efficiently: fluid mechanics, plasma physics, optics, perturbation technology, continuum mechanics, numerical analysis for physics, mechanics, non-linear evolution equations, theoretical chemistry and other applications.
Multiparadigm research: a new direction of language design
Authors: John Placer
Venue: ACM SIGPLAN Notices (1991)

Multiparadigm research is a relatively new direction in programming language design. In this paper we discuss several aspects of this research area. We consider some of the ideas that underlie the multiparadigm point of view, we examine some of the motivations behind the work being done and we consider some of the directions within this field of work. Finally we offer a short example that suggests the potential usefulness of combining several paradigms into one linguistic framework.
On performance and space usage improvements for parallelized compiled APL code
Authors: Dz-ching Ju, Wai-Mee Ching, Chuan-lin Wu
Venue: ACM SIGAPL APL Quote Quad (1991)

Loop combination has been a traditional optimization technique employed in APL compilers, but may introduce dependencies into the combined loop. We propose an analysis method by which the compiler can keep track of the change of the parallelism when combining high-level primitives. The analysis is necessary when the compiler needs to decide a trade-off between more parallelism and a further combination. We also show how the space usage, as well as the performance, improves by using system calls with the aid of garbage collection to implement a dynamic memory allocation. A modification of the memory management scheme can also increase available parallelism. Our experimental results indicate that the performance and the space usage improve appreciably with the above enhancements.
Architecture of a graphics processor (abstract)
Authors: Gautam B. Singh
Venue: Proceedings of the 19th annual international symposium on Computer architecture (1992)

The design principles that were applied in the design of the integer-RISC machine, are applied to the design of the Reduced Instruction Set Graphics Processor. The processor instruction is defined after critical evaluation of the common graphics operations. Single cycle operation (in a pure RISC style) are performed through instructions for primitive graphics as well as general purpose computations. This processor is envisioned to become the CPU of choice for the ergonomic applications that rely heavily on graphics capabilities for user interface bandwidth improvement. The motivation for integrating graphics with general-purpose computations stems from the performance enhancement acheived due to increased integration levels, and the program portability offered by a single processor based systems.
Autodirective microphone systems for natural communication with speech recognizers
Authors: J. L. Flanagan, R. Mammone, G. W. Elko
Venue: Proceedings of the workshop on Speech and Natural Language (1991)

Two technological advances support new sophistication in sound capture; namely, high-quality low-cost electret microphones and high-speed economical signal processors. Combined with new understanding in acoustic beamforming, these technologies permit spatially-selective transduction of speech signals several octaves in bandwidth. Spatial selectivity mitigates the effects of noise and reverberation, and digital processing provides the capability for speech-seeking, autodirective performance. This report outlines the principles of autodirective beamforming for acoustic arrays, and it describes two experimental implementations. It also summarizes the direction and emphasis of continuing research.
Evolving task oriented systems
Authors: Paul Seaton, Tom Stewart
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

This paper describes an approach to developing systems which can be summarised as &lsquo;analyse top-down, design middle-out, and build bottom-up&rsquo;. A case study is described in which this approach is used to develop a system to support staff who select new products for a major UK company. The novelty of the approach lies in its use of task analysis to define an appropriate domain for the system and then the use of a working prototype to grow a system from the bottom up. The project involved using simple development tools which allowed the users to start getting business benefit from the system right from the start. Their use could therefore develop as the system evolved.
A Method for Symbolic Evaluation of Indefinite Integrals Containing Special Functions or their Products
Authors: Jean C. Piquette
Venue: Journal of Symbolic Computation (1991)

A method that can be used to extend the capabilities of the integrator of computer mathematics systems to include symbolic evaluation of indefinite integrals containing special functions or their products is described. The approach is based on a technique of indefinite integration which was first described in a previous article [Piquette, J. C., Van Buren, A. L. (1984). Technique for evaluating indefinite integrals involving products of certain special functions. SIAM J. Math, Anal. 15, 845-855]. Special-case expressions which are useful in evaluating integrals containing either one or two Bessel functions, Legendre functions, Hermite functions, or Laguerre functions are also given. An implementation of this method in the SMP(TM) language is described. A tabulation of some of the integrals that have been evaluated using the method is given.
Finding the hidden path: time bounds for all-pairs shortest paths
Authors: David R. Karger, Daphne Koller, Steven J. Phillips
Venue: Proceedings of the 32nd annual symposium on Foundations of computer science (1991)

The all-pairs shortest paths problem in weighted graphs is investigated. An algorithm called the hidden paths algorithm, which finds these paths in time O(m*+n n/sup 2/ log n), where m* is the number of edges participating in shortest paths, is presented. It is argued that m* is likely to be small in practice, since m*=O(n log n) with high probability for many probability distributions on edge weights. An Omega (mn) lower bound on the running time of any path-comparison-based algorithm for the all-pairs shortest paths problem is proved.
Interoperability in an open application environment
Authors: Steven Pemberton
Venue: ACM SIGOIS Bulletin (1992)

Current application environment tend to be inconsistent, inflexible, arcanr, and non-interoperable. This is to a great extent due to the isolation of each application. Views is an environment where these issues are addressed by offering a completely integrated environment where all user interface issues have been taken out of the hands of the application programmer.
Teaching loop invariants to beginners by examples
Authors: Wing C. Tam
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

Since the concept of a loop invariant has long been recognized as the correct way to design and analyse loops, it is important that its application to programming be introduced to students and programmers as early as possible. This paper describes how to teach the use of loop invariants to reason about loops and to program them correctly in introductory programming courses by following a systematic set of steps coupled with examples.
Nonexistence of degree bounds of various bases for ideals of polynomials over the integers
Authors: Wei Li
Venue: ACM SIGSAM Bulletin (1992)

It has been proved in [L] that there is no universal degree bound of Gr ouml;bner bases when the coefficient ring is Z, where Gr ouml;bner bases are defined as in [T]. In this paper we prove that the same result is true for each of the following constructive bases: (1) Gr ouml;bner bases in the sense of [Bu]; (2) Gr ouml;bner bases in the sense of [KK]; (3) detaching bases in the sense of [A]; (4) Szekeres basis in the sense of [S]. We also discuss several open problems about degree bounds, which are motivated by our examples as well as by results from commutative algebra.
An Adaptive and Fault Tolerant Wormhole Routing Strategy for k-ary n-cubes
Authors: Daniel H. Linder, Jim C. Harden
Venue: IEEE Transactions on Computers (1991)

The concept of virtual channels is extended to multiple virtual communication systems that provide adaptability and fault tolerance in addition to being deadlock-free. A channel dependency graph is taken as the definition of what connections are possible, and any routing function must use only those connections defined by it. Virtual interconnection networks allowing adaptive, deadlock-free routing are examined for three k-ary n-cube topologies: unidirectional, torus-connected bidirectional, and mesh-connected bidirectional.
The design of voice-driven interfaces
Authors: Alexander I. Rudnicky
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

This paper presents some issues that arise in building voice-driven interfaces to complex applications and describes some of the approaches that we have developed for this purpose. To test these approaches, we have implemented a voice spreadsheet and have begun observation of users interacting with it.
Distributed Shared Memory: A Survey of Issues and Algorithms
Authors: Bill Nitzberg, Virginia Lo
Venue: Computer (1991)

An overview of distributed shared memory (DSM) issues is presented. Memory coherence, design choices, and implementation methods are included. The discussion of design choices covers structure and granularity, coherence semantics, scalability, and heterogeneity. Implementation issues concern data location and access, the coherence protocol, replacement strategy, and thrashing. Algorithms that support process synchronization and memory management are discussed.
Built-in Self-Testing of Random-Access Memories
Authors: Manoj Franklin, Kewal K. Saluja
Venue: Computer (1990)

Built-in self-test (BIST) methods are examined, including the fault models and the test algorithms on which the BIST implementations are based. The notion of generic test architectures suitable for implementing a wide variety of test algorithms is introduced. A taxonomy for test architectures is provided and used to categorize BIST implementations, and important implementations are surveyed. It is demonstrated that BIST is a viable solution to the problem of testing large memories and that approaches based on test architectures rather than on test algorithms are more versatile and will likely predominate in the future.
Hot-Spot Contention in Binary Hypercube Networks
Authors: Sivarama P. Dandamudi, Derek L. Eager
Venue: IEEE Transactions on Computers (1992)

Consideration is given to the impact of hot-spot contention in distributed-memory multicomputer systems. Since the binary hypercube network offers a reasonable compromise between network cost and performance, two hypercube-based static interconnection networks are considered. One is a standard binary hypercube and the other is a binary hypercube-based hierarchical interconnection network. The impact of hot-spot contention in both these networks is studied.
Speech patterns in video-mediated conversations
Authors: Abigail J. Sellen
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

This paper reports on the first of a series of analyses aimed at comparing same room and video-mediated conversations for multiparty meetings. This study compared patterns of spontaneous speech for same room versus two video-mediated conversations. One video system used a single camera, monitor and speaker, and a picture-in-a-picture device to display multiple people on one screen. The other system used multiple cameras, monitors, and speakers in order to support directional gaze cues and selective listening. Differences were found between same room and video-mediated conversations in terms of floor control and amount of simultaneous speech. While no differences were found between the video systems in terms of objective speech measures, other important differences are suggested and discussed.
Compile-time transformations and optimization of parallel Divide-and-Conquer algorithms
Authors: B. Carpentieri, G. Mou
Venue: ACM SIGPLAN Notices (1991)

In this paper we show how it is often possible to transform and optimize parallel algorithms based on the Divide-and-Conquer paradigm at compile time. Our goal is to make Divide-and-Conquer algorithms suitable for implementation on hypercube-like parallel architectures, such as the Connection Machine, even if the original algorithm implies a division function that is not the left-right division and/or communication pattern that cannot be implemented by direct-neighbor communication.Our tools are the formal model of the Divide-and-Conquer paradigm developed in [4] and the parallel programming language derived from this model: Divacon [2], [3].Our main results concern the replacement of last-k communication (broadcast) and mirror image communication with correspondent communication and the transformation from odd-even division to left-right division and vice versa. By using each of the techniques described in this paper it is possible to improve many Divide-and-Conquer algorithms by a factor of log(n).
Single Lens Stereo with a Plenoptic Camera
Authors: Edward H. Adelson, John Y. A. Wang
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

Ordinary cameras gather light across the area of their lens aperture, and the light striking a given subregion of the aperture is structured somewhat differently than the light striking an adjacent subregion. By analyzing this optical structure, one can infer the depths of the objects in the scene, i.e. one can achieve single lens stereo. The authors describe a camera for performing this analysis. It incorporates a single main lens along with a lenticular array placed at the sensor plane. The resulting plenoptic camera provides information about how the scene would look when viewed from a continuum of possible viewpoints bounded by the main lens aperture. Deriving depth information is simpler than in a binocular stereo system because the correspondence problem is minimized. The camera extracts information about both horizontal and vertical parallax, which improves the reliability of the depth estimates.
Hermite canonical form and Smith canonical form of a matrix over a principal ideal domain
Authors: Pasqualina Conti
Venue: ACM SIGSAM Bulletin (1990)

This paper presents computational aspects of Smith and Hermite normal forms for matrices over general principal ideal domains. After reviewing the standard definitions and properties of Hermite and Smith normal forms, we ask when there is an effective algorithm which will find a unique canonical form for all matrices in the same equivalence class. We show that the ability to compute canonical members of an associate class and canonical representatives of a residue class in the underlying ring are necessary and sufficient conditions for an effective procedure to find unique Hermite and Smith forms. We then present a uniform technique for reducing intermediate expression swell during the computation of Smith and Hermite normal forms for matrices over general principal ideal domains. This generalizes previous work by handling non-square matrices which are not of full column rank. We also present examples which show that the heuristic of directly computing modulo the determinant as proposed by some can yield the wrong answer. We instead compute with the matrix augmented by the determinant times the identity matrix. This always yields the correct result and has the desired effect of allowing one to keep all elements which occur during the computation bounded by the determinant.
Exploratory language design
Authors: Edward A. Ipser,  Jr.
Venue: ACM SIGPLAN Notices (1992)

Exploratory language design is an iterative process of language refinement the purpose of which is to define a language that closely fits a given domain of applications. First, choose a domain of applications and a language starting point. Then iteratively choose an application in the domain, write the solution to the application in the language, and fit the language to the application until satisfied.
Specification of Fault-Tolerant System Issues by predicate/Transition Nets and Regular Expressions-Approach and Case Study
Authors: Fevzi Belli, Karl-E. Grosspietsch
Venue: IEEE Transactions on Software Engineering (1991)

A method to systematically integrate fault tolerance properties into the design of complex software systems is presented. The method exploits a formal specification of the system in which the amount of necessary redundancy can be determined. The system description is based on a combination of a predicate/transition net with regular expressions. The net model provides a formal overview of the system behavior in general, supporting the correct understanding of potential concurrency in the system processes. Regular expressions are used to model the sequential behavior of single-system components in detail. Both model layers provide well-defined levels of error detection; the regular expressions enable the system designer to also determine and introduce redundancy to achieve error correction. The techniques used to describe and analyze system behavior are explained using a case study that contains a stepwise-refined specification and analysis of a multistory shelving system model that has been implemented using the method presented. It is shown that the method applies to any software system which is to be protected against the considered errors.
Objects for a database programming language
Authors: Antonio Albano, Giorgio Ghelli, Renzo Orsini
Venue: Proceedings of the third international workshop on Database programming languages : bulk types persistent data: bulk types persistent data (1992)

An object mechanism is presented for a strongly typed, statically checkable, object-oriented database programming language. The main features of the proposal are (a) an object type construct to define objects with hidden state and methods which can be organized in an inclusion hierarchy to exploit the benefits of inheritance and late binding, (b) the separation between the definition of an object type, or interface, and its implementation to allow the evolution of the implementation of an object type, without affecting the rest of the system, (c) an extension operator to transform in a type-safe way the type of an object.
Dynamic scheduling on parallel machines
Authors: Anja Feldmann, Jiří Sgall, Shang-Hua Teng
Venue: Proceedings of the 32nd annual symposium on Foundations of computer science (1991)

The problem of online job scheduling on various parallel architectures is studied. An O((log log n)/sup 1/2/)-competitive algorithm for online dynamic scheduling on an n*n mesh is given. It is proved that this algorithm is optimal up to a constant factor. The algorithm is not greedy, and the lower bound proof shows that no greedy-like algorithm can be very good. The upper bound result can be generalized to any fixed-dimensional meshes. Competitive scheduling algorithms for other architectures are given.
On the computational power of sigmoid versus boolean threshold circuits (extended abstract)
Authors: Wolfgang Maass, Georg Schnitger, Eduardo D. Sontag
Venue: Proceedings of the 32nd annual symposium on Foundations of computer science (1991)

The power of constant depth circuits with sigmoid (i.e., smooth) threshold gates for computing Boolean functions is examined. It is shown that, for depth 2, constant size circuits of this type are strictly more powerful than constant size Boolean threshold circuits (i.e., circuits with Boolean threshold gates). On the other hand it turns out that, for any constant depth d, polynomial size sigmoid threshold circuits with polynomially bounded weights compute exactly the same Boolean functions as the corresponding circuits with Boolean threshold gates.
Usability tests refine requirements (abstract)
Authors: Lynne Marie Davis
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

The traditional approach to developing a computer system is to gather requirements, write the specifications, code the programs, write the documentation, test, distribute, then wait for the accolades. Sometimes the accolades are long in coming. Sometimes they never come. People draw funny cartoons about how the system turns out differently form the basic requirements. These cartoons depict the historical struggle between users and programmers&hellip;between requirements and finished products. Why can't developers interpret requirements and build systems the users are really asking for? In an attempt to solve this problem, requirements-definition documents and programming specifications are routed back to the users to review. But, do they really review them? One way to improve the development process is to break from tradition and do usability testing in the design phase. Refine the requirements using the test results and the system will be a better match between desires and deliverables. A usability test is conducted in a controlled environment, often a human factors lab, with typical users doing sample tasks. Prototypes of the user interface are necessary, but not complete functional code. As testers perform their everyday tasks, observers record their impressions. These are analyzed and become recommendations back to the developers to include in the final product. For example, a test scenario may be designed to exercise the placement of the cursor on the display screen. How irritating to find a cursor on a protected field. You can't enter date in this field, so why have the cursor there? Did the requirements definition tell where to put the cursor? Probably not. Usually it specifies function without noting usability specifics. So how could the programmer know? Usability testing during the design phase is a good way to find out if the design will meet the users' needs. After all, that's what computer systems are all about.