ppxscal/embedding_network huggingface dataset:
Communication network analysis with COMNET 11.5
Authors: R. Mills
Venue: Proceedings of the 21st conference on Winter simulation (1989)

COMNET II.5 is a general SIMSCRIPT II.5-based model for the performance analysis of circuit, message, or packet-switching networks. A variety of routing algorithms are built-in. After creating a network description with a convenient menu-driven editor, simulation follows immediately. There are no programming delays. Network operation is animated during the simulation. Reports show blocking probabilities, call queueing and packet delays, network throughput, link group utilization, and link group queue statistics. Some of the major enhancements that have been added to COMNET II.5 during the past year include capabilities for modeling multidestination messages, empirical probability distributions, flood routing, and access facilities. An access facility can be a point-to-point or multipoint line or a local area network.
The Institut Blaise-Pascal (1946-1969) from Couffignal's Machine to Artificial Intelligence
Authors: P. E. Mounier-Kuhn
Venue: IEEE Annals of the History of Computing (1989)

The Institut Blaise-Pascal, created in 1946, was France's first laboratory devoted to electronic computers, analog as well as digital. Its analog division, under L. Malavard, developed rheological methods that had been initiated in the early 1930s. Ifs numerical division was headed first by L. Couffignal who did not succeed in building his electronic calculator, based on a very particular design; then by R. de Possel, who actively developed computer facilities, computer science teaching and research, and undertook to achieve a universal optical character recognition system. The Institut Blaise-Pascal was divided into several independent teams in 1969.
Solution of the 3-D Euler equations for the flow about a fighter aircraft configuration using a hypercube parallel processor
Authors: D. A. Weissbein, J. F. Mangus, M. W. George
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications - Volume 2 (1989)

The Computational Fluid Dynamics (CFD) code FL057, which solves the 3-D Euler Equations using an explicit, finite volume, Runge-Kutta algorithm, was implemented on an Intel IPSC-MX parallel processor. Spatial decomposition was effected on the solution grid about a fighter aircraft configuration and Binary Reflected Graycodes were used to map the computational domain onto the IPSC insuring nearest neighbor communication. Results and timings of the implementation are presented with a comparison of the IPSC and a uniprocessor machine of similar classification to assess the performance of the IPSC on FL057. Suggested improvements to the current version of the parallelized code are listed to aid load balancing, vectorization, and more efficient memory use.
The use of single family of languages for program development
Authors: S. Rotenstreich
Venue: Proceedings of the 17th conference on ACM Annual Computer Science Conference (1989)

Program development involves many steps and activities. Among these one can mention specifications, design, coding, debugging, testing, modifications, display and experiments. All these activities are supported, at least partially, by computer languages. Today, the different activities are supported by different languages. This is a problematic situation. There were several attempts to devise a single language approach to program development. However, these attempts were either too limited or too abstract to form a concrete and immediate answer. This report shows how to extend algebraic programming languages to cover most of the development activities. It therefore offers the ability to support all development done with a programming language with a single extended language based on that programming language. The extensions are presented through Ada. We make use of existing extensions supporting specifications and design, and add extensions supporting activities taking place after coding. The extensions do not change the language they are based on, and they are used only to support development activities.
FACE core environment: the model and its application in CAE/CAD tool development
Authors: W. D. Smith, D. Duff, M. Dragomirecky, J. Caldwell, M. Hartman, J. Jasica, M. A. d'Abreu
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

Many aspects of design automation software have similar requirements for representing, manipulating, and storing design information. The recognition of these common requirements in CAD tools, allows the Flexible Architecture Compilation Environment's (FACE) Core Environment to provide a suite of high level tools for the CAD developer. The Core Environment software has been developed using object-oriented software technology, and may be readily adapted to specific applications. The focus of the core environment is to improve the productivity of CAD tool developers through better tool integration and a state-of-the-art software development environment. This Core Environment software has been used in the development of an integrated tool set covering algorithm specification, structural synthesis, and physical assembly of digital hardware systems. The focus of this paper is on the Core Environment's organization and its use in application tool development.
A simplified six-waveform type method for delay fault testing
Authors: W.-W. Mao, M.D. Ciletti
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

A new, simplified waveform method is presented for delay fault testing. The method enables accurate calculation of a delay fault detection threshold for definitely detectable faults, and a delay fault range for possibly detectable faults. The method is shown to correctly classify definitely detectable faults which are mis-classified by methods recently reported elsewhere [1,2]. A quantitative delay fault model with variable fault size is used, and the effect of the delay fault is explicitly described by the new waveform method. The calculation of the detectable delay size threshold occurs in linear time for any definitely detectable fault.
Extracting &ohgr;'s programs from proofs in the calculus of constructions
Authors: C. Paulin-Mohring
Venue: Proceedings of the 16th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1989)

We define in this paper a notion of realizability for the Calculus of Constructions. The extracted programs are terms of the Calculus that do not contain dependent types. We introduce a distinction between informative and non-informative propositions. This distinction allows the removal of the &ldquo;logical&rdquo; part in the development of a program. We show also how to use our notion of realizability in order to interpret various axioms like the axiom of choice or the induction on integers. A practical example of development of program is given in the appendix.
A gaze-responsive self-disclosing display
Authors: India Starker, Richard A. Bolt
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: Empowering people (1990)

An information display system is described which uses eye-tracking to monitor user looking about its graphics screen. The system analyzes the user's patterns of eye movements and fixations in real-time to make inferences about what item or collection of items shown holds most relative interest for the user. Material thus identified is zoomed-in for a closer look, and described in more detail via synthesized speech.
Performance of a two-headed disk system when serving database queries under the scan policy
Authors: Y. Manolopoulos, J. G. Kollias
Venue: ACM Transactions on Database Systems (TODS) (1989)

Disk drives with movable two-headed arms are now commercially available. The two heads are separated by a fixed number of cylinders. A major problem for optimizing disk head movement, when answering database requests, is the specification of the optimum number of cylinders separating the two heads. An earlier analytical study assumed a FCFS model and concluded that the optimum separation distance should be equal to 0.44657 of the number of cylinders N of the disk. This paper considers that the SCAN scheduling policy is used in file access, and it applies combinatorial analysis to derive exact formulas for the expected head movement. Furthermore, it is proven that the optimum separation distance is N/2 - 1 (&lceil;N/2 - 1&rceil; and &lfloor;N/2 - 1&rfloor;) if N is even (odd). In addition, a comparison with a single-headed disk system operating under the same scheduling policy shows that if the two heads are optimally spaced, then the mean seek distance is less than one-half of the value obtained with one head. In fact that the SCAN policy is used for many database applications (for example,batching and secondary key retrieval) demonstrates the potential of two-headed disk systems for improving the performance of database systems.
The impact of the LCC-optimization on the performance of a static scope LISP interpreter
Authors: R. Beckmann, K.-U. Felgentreu
Venue: Proceedings of the 1988 ACM SIGSMALL/PC symposium on ACTES (1988)

The Low Cost Call - Optimization was introduced as a general approach to the optimization of function calls in shallow binding implementations of applicative static scope languages. The basic idea of the LCC-optimization is to avoid saving obsolete environments for a large class of function calls, thus exceeding the usual optimization of tailrecursive and covered tailrecursive calls. This paper describes how the new technique has been applied in the implementation of a portable static scope LISP interpreter for microcomputers, called LCINT. In a benchmark test we measure the impact of the LCC-optimization on the performance of LCINT. The results show that this technique is particularly valuable for small systems with a rather limited storage. Whereas some of the results fully meet our expectations, others are rather surprising and lead us to certain conclusions for further research.
Scans as Primitive Parallel Operations
Authors: G. E. Blelloch
Venue: IEEE Transactions on Computers (1989)

A study of the effects of adding two scan primitives as unit-time primitives to PRAM (parallel random access machine) models is presented. It is shown that the primitives improve the asymptotic running time of many algorithms by an O(log n) factor, greatly simplifying the description of many algorithms, and are significantly easier to implement than memory references. It is argued that the algorithm designer should feel free to use these operations as if they were as cheap as a memory reference. The author describes five algorithms that clearly illustrate how the scan primitives can be used in algorithm design: a radix-sort algorithm, a quicksort algorithm, a minimum-spanning-tree algorithm, a line-drawing algorithm, and a merging algorithm. These all run on an EREW (exclusive read, exclusive write) PRAM with the addition of two scan primitives and are either simpler or more efficient than their pure PRAM counterparts. The scan primitives have been implemented in microcode on the Connection Machine system, are available in PARIS (the parallel instruction set of the machine).
On the complexity of queries in the logical data model
Authors: G. M. Kuper, M. Y. Vardi
Venue: Lecture notes in computer science on ICDT '88 (1988)

We investigate the complexity of query processing in the logical data model (LDM). We use two measures: data complexity, which is complexity with respect to the size of the data, and expression complexity, which is complexity with respect to the size of the expressions denoting the queries. Our investigation shows that while the operations of product and union are essentially first-order operations, the power set operation is inherently a higher-order operation and is exponentially expensive. We define a hierarchy of queries based on the depth of nesting of power set operations and show that this hierarchy corresponds to a natural hierarchy of Turing machines that run in multiply exponential time.
Content-Addressable and Associative Memory: Alternatives to the Ubiquitous RAM
Authors: Lawrence Chisvin R. James Duckworth
Venue: Computer (1989)

Content-addressable and associative processing systems are explained, and it is shown that such systems are commercially feasible. Content-based archiving and retrieving are compared with address-based storage methods. The principles, advantages and obstacles of content-addressable storage are examined and associative processing methods and architectures are described. Software for associative systems is also discussed.
Exploratory evaluation of a planar foot-operated cursor-positioning device
Authors: G. Pearson, M. Weiser
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1988)

The use of feet instead of hands to perform workstation cursor-positioning and related functions has been the subject of an on-going investigation. In the exploratory study reported here, a particular foot-operated device, the planar slide mole, was assessed against a mouse in a target-selection task. The study showed that novices can learn to select fairly small targets using a mole; for a target size of 1/8&Prime; square, the response time equaled that of the mouse when keyboard homing time was taken into account.
Scheduling high-level blocks for functional simulation
Authors: Z. Wang, P. M. Maurer
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

This paper presents a method for scheduling high-level blocks for functional simulation under the assumptions that circuits may be cyclic (due to element grouping), and that blocks cannot be broken down into simpler elements. The solution presented here may simulate one block many times per clock period. Obtaining a minimal schedule for a cyclic circuit is shown to be NP-complete, and two approximation algorithms are presented, along with empirical data to evaluate their effectiveness.
On the influence of scale in a distributed system
Authors: M. Satyanarayanan
Venue: Proceedings of the 10th international conference on Software engineering (1988)

Scale should be recognized as a primary factor influencing the architecture and implementation of distributed systems. This paper uses Andrew, a distributed environment at Carnegie Mellon University, to validate this proposition. The design of Andrew is dominated by considerations of performance, operability and security. Caching of information and placing trust in as few machines as possible emerge as two general principles that enhance scalability. The separation of concerns made possible by specialized mechanisms is also valuable. Heterogeneity is a natural consequence of growth and anticipating it in the initial stages of system design is important. A location transparent shared file system considerably enhances the usability of a distributed environment.
A program debugger for a systolic array: design and implementation
Authors: Bernd Bruegge, Thomas Gross
Venue: ACM SIGPLAN Notices (1989)

The Warp machine consists of a programmable linear systolic array connected to a general-purpose workstation host. Warp can be accessed either locally from this host or remotely from a large number of workstations connected to a local area network. Since the linear arrangement of the cells in the array restricts direct input and output with the host to the boundary cells, a source language debugger is important for program development. The Warp debugger is integrated into the Warp Programming Environment (WPE) which provides a uniform interface to the Warp machine. The debugger presents a conventional debugging model that includes breakpoints for individual cells as well as the inspection of the local state of each of the cells in the array. Although this user model is fairly simple, the implementation had to overcome several problems resulting from the parallel architecture of the machine and the distributed architecture of the programming environment.
Theory-W software project management: a case study
Authors: B. Boehm, R. Ross
Venue: Proceedings of the 10th international conference on Software engineering (1988)

The search for a single unifying principle to guide software project management has been relatively unrewarding to date. Most candidate principles are either insufficiently general to apply in many situations, or so general that they provide no useful specific guidance. This paper presents a candidate unifying principle which appears to do somewhat better. Reflecting various alphabetical management theories (X, Y, Z), it is called the Theory W approach to software project management. Theory W: Make Everyone a Winner The paper explains the Theory W principle and its two subsidiary principles: Plan the flight and fly the plan; and, Identify and manage your risks. To test the practicability of Theory W, a case study is presented and analyzed: the attempt to introduce new information systems to a large industrial corporation in an emerging nation. The case may seem unique, yet it is typical. The analysis shows that Theory W and its subsidiary principles do an effective job both in explaining why the project encountered problems, and in prescribing ways in which the problems could have been avoided.
Optimal code generation for expression trees: an application BURS theory
Authors: E. Pelegrí-Llopart, S. L. Graham
Venue: Proceedings of the 15th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1988)

A Rewrite System is a collection of rewrite rules of the form &agr; &bgr; where &agr; and &bgr; are tree patterns. A rewrite system can be extended by associating a cost with each rewrite rule, and by defining the cost of a rewrite sequence as the sum of the costs of all the rewrite rules in the sequence. The REACHABILITY problem for a rewrite system R is, given an input tree T and a fixed goal tree G, to determine if there exists a rewrite sequence in R, rewriting T into G and, if so, to obtain one such sequence. The C-REACHABILITY problem is similar except that the obtained sequence must have minimal cost among all those sequences writing T into G. This paper introduces a class of rewrite systems called Bottom-Up Rewrite Systems (BURS), and a table-driven algorithm to solve REACHABILITY for member of the class. This algorithm is then modified to solve C-REACHABILITY and specialized for a subclass of BURS so that all cost manipulation is encoded into the tables and is not performed explicitly at solving time. The subclass extends the simple machine grammars [AGH84], rewrite systems used to describe target machine architectures for code generation, by allowing additional types of rewrite rules such as commutativity transformations. A table-driven code generator based on solving C-REACHABILITY has been implemented and tested with several machine descriptions. The code generator solves C-REACHABILITY faster than a comparable solver based on Graham-Glanville techniques [AGH84] (a non-optimal technique), yet requires only slightly larger tables. The code generator runs much faster than recent proposals to solve C-REACHABILITY that use pattern matching and deal with costs explicitly at solving time [AGT86, HeD87, WeW86]. The BURS theory generalizes and unifies the bottom-up approaches of Henry/Damron [HeD87] and Weisgerber/Wilhelm [WeW86].
The impact of recovery on concurrency control
Authors: W. E. Weihl
Venue: Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1989)

It is widely recognized by practitioners that concurrency control and recovery for transaction systems interact in subtle ways. In most theoretical work, however, concurrency control and recovery are treated as separate, largely independent problems. In this paper we investigate the interactions between concurrency control and recovery. We consider two general recovery methods for abstract data types, update-in-place and deferred-update. While each requires operations to conflict if they do not &ldquo;commute,&rdquo; the two recovery methods require subtly different notions of commutativity. We give a precise characterization of the conflict relations that work with each recovery method, and show that each permits conflict relations that the other does not. Thus, the two recovery methods place incomparable constraints on concurrency control. Our analysis applies to arbitrary abstract data types, including those with operations that may be partial or non-deterministic.
Layered construction for deformable animated characters
Authors: J. E. Chadwick, D. R. Haumann, R. E. Parent
Venue: Proceedings of the 16th annual conference on Computer graphics and interactive techniques (1989)

A methodology is proposed for creating and animating computer generated characters which combines recent research advances in robotics, physically based modeling and geometric modeling. The control points of geometric modeling deformations are constrained by an underlying articulated robotics skeleton. These deformations are tailored by the animator and act as a muscle layer to provide automatic squash and stretch behavior of the surface geometry. A hierarchy of composite deformations provides the animator with a multi-layered approach to defining both local and global transition of the character's shape. The muscle deformations determine the resulting geometric surface of the character. This approach provides independent representation of articulation from surface geometry, supports higher level motion control based on various computational models, as well as a consistent, uniform character representation which can be tuned and tweaked by the animator to meet very precise expressive qualities. A prototype system (Critter) currently under development demonstrates research results towards layered construction of deformable animated characters.
Using Linda for supercomputing on a local area network
Authors: R. A. Whiteside, J. S. Leichter
Venue: Proceedings of the 1988 ACM/IEEE conference on Supercomputing (1988)

A distributed parallel processing system based on the LINDA programming constructs has been implemented on a local area network of computers. This system allows a single application program to utilize many machines on the network simultaneously. Several applications have been implemented on the network at Sandia National Laboratories and have achieved performances considerably faster than that of a Cray-1S. Several collections of machines have been used including up to eleven DEC VAXes, three Sun/3 workstations, and a PC.
t-TDA-Diagnosable Systems
Authors: S.-C. Chu, J. R. Armstrong
Venue: IEEE Transactions on Computers (1989)

A testable diagnosis array (TDA) is proposed for carrying out system-level fault diagnosis (based on the PMC model) centrally and in a non-hard-core manner. This diagnostics device is constructed with simple reliable logic cells. A characterization of t-TDA-diagnosable systems, based on an algebraic relationship between the testing graph T/sub n/ of a system of n component and its corresponding TDA, is given. It is shown that the TDA performs the diagnosis correctly and reaches its stable state in a number of clock periods related to the t-diagnostic diameter of T. A special class of t-TDA-diagnosable systems is defined, and an example from that class is used to illustrate the diagnosability of a system using a TDA.