ppxscal/embedding_network huggingface dataset:
An approach for integration of data processing in a distributed enviornment
Authors: M. M. Owrang, L. L. Miller
Venue: Proceedings of the 17th conference on ACM Annual Computer Science Conference (1989)

A translation process designed to translate queries between data models in a distributed environment is examined. Such a translation mechanism will enable the user to have access to the database resource in a distributed database for which different data base management systems coexist. The translation process is described and examples illustrating the process are given. The discussion has been limited to operating in the environment where the source and target database have the same semantics. Hypergraphs are used as the intermediate representation format for the query during the translation process. The semantics of both the source and target database are described in terms of hypergraphs. In addition, the hypergraph is extended to incorporate the operations of the data manipulation language in order to define a general model for query translation.
Blitz: a rule-based system for massively parallel architectures
Authors: K. Morgan
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications - Volume 2 (1989)

The rule-based system has emerged as an important tool to developers of artificial intelligence programs. Because of the computational resources required to realize the MATCH-SELECT-EXECUTE cycle of rule-based systems, researchers have been trying to introduce parallelism into these systems for some time. We describe a new approach to parallel rule-based systems which exploits fine-grained hypercube hardware. The new algorithms for parallel rule matching and simultaneous execution of several rules at once are presented. Experimental results using a Connection Machine* implementation of BLITZ are presented.
PCTE Esprit and Pact
Authors: I. Thomas
Venue: ACM SIGSOFT Software Engineering Notes (1988)

The PCTE initiative has long ago passed beyond the confines of the PCTE Esprit project. It now encompasses a large number of projects, organisations and programmes. This paper is an updated version of one that was given at the Esprit Technical Week 87. It describes the PCTE initiative by discussing the work being done on implementations of the PCTE interfaces, their formalisation and evolution. It goes on to describe current efforts to build integrated environments on the interfaces and describes the Pact project in particular. Finally, there is an attempt to place PCTE in a world context.
Reconstructing Convex Sets from Support Line Measurements
Authors: J. L. Prince, A. S. Willsky
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

Algorithms are proposed for reconstructing convex sets given noisy support line measurements. It is observed that a set of measured support lines may not be consistent with any set in the plane. A theory of consistent support lines which serves as a basis for reconstruction algorithms that take the form of constrained optimization algorithms is developed. The formal statement of the problem and constraints reveals a rich geometry that makes it possible to include prior information about object position and boundary smoothness. The algorithms, which use explicit noise models and prior knowledge, are based on maximum-likelihood and maximum a posteriori estimation principles and are implemented using efficient linear and quadratic programming codes. Experimental results are presented. This research sets the stage for a more general approach to the incorporation of prior information concerning the estimation of object shape.
A Systolic Architecture for Fast Dense Matrix Inversion
Authors: A. El-Amawy
Venue: IEEE Transactions on Computers (1989)

An array that inverts an n*n dense matrix in 5n-1 time units, including I/O time, is presented. The inversion algorithm consists of three phases and assumes that Gaussian elimination without pivoting can be applied. The array, which consists of 2n/sup 2/-n simple processing elements, implements and overlaps the execution of all three phases without any need for intermediate I/O or reconfiguration. An efficient data-steering technique which is well suited for feedback recurrences is utilized.
Parallel and vector conjugate gradient-like algorithms for sparse nonsymmetric linear systems
Authors: C. Radicati de Brozolo, Y. Robert
Venue: Proceedings of the 2nd international conference on Supercomputing (1988)

We describe a vector and parallel implementation on the IBM 3090-600/VF of two extension of the preconditioned conjugate gradient algorithm for nonsymmetric sparse linear systems, with arbitrary scarcity structure. For both methods, we consider preconditioning by a diagonal matrix and by an incomplete LU factorization.
The compact display of arbitrary nested arrays
Authors: D. A. Rabenhorst
Venue: ACM SIGAPL APL Quote Quad (1987)

An enhanced array display function, upward compatible from the one supplied with APL2, is presented. It overcomes several difficulties involved with the display of very large or very deep nested arrays, and permits convenient examination of arrays which would otherwise overflow the screen or observation window. Sub-array replication and sub-array similarity in the displayed array are considered at every depth, and presented in a straightforward shorthand notation if invoked. Also, leaf detail is elided by general compaction, but only if it precludes a reasonable overall display size.
Effects of interface design upon user productivity
Authors: W. A. Bailey, S. T. Knox, E. F. Lynch
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1988)

Eight subjects experienced in the use of both 7000 and 11000 series oscilloscopes performed four typical tasks with each scope. The 7000 interface is a dedicated physical control system, while the 11000 system employs icons, pop-up menus, assignable controls, and a touch panel. On each trial the task time and measurement accuracy were recorded. Each experimental session was video recorded and verbal protocols were collected. These allowed decomposition of the subjects' behaviors into categories that would account for performance differences between the two scopes. A 77% performance difference is explained in terms of the cognitive factors of strategy selections and recall of operational details.
Leases: an efficient fault-tolerant mechanism for distributed file cache consistency
Authors: C. Gray, D. Cheriton
Venue: Proceedings of the twelfth ACM symposium on Operating systems principles (1989)

Caching introduces the overhead and complexity of ensuring consistency, reducing some of its performance benefits. In a distributed system, caching must deal with the additional complications of communication and host failures. Leases are proposed as a time-based mechanism that provides efficient consistent access to cached data in distributed systems. Non-Byzantine failures affect performance, not correctness, with their effect minimized by short leases. An analytic model and an evaluation for file access in the V system show that leases of short duration provide good performance. The impact of leases on performance grows more significant in systems of larger scale and higher processor performance.
A core course in computer theory: design and implementation issues
Authors: D. J. Bagert,  Jr.
Venue: Proceedings of the twentieth SIGCSE technical symposium on Computer science education (1989)

This paper describes the design and implementation of a junior-level course in formal languages and automata theory which satisfies CSAB guidelines for the computer science core curriculum in the area of theoretical foundations of computer science. The optimal prerequisites for such a course, as well as its impact on advanced computer science courses, are discussed. Several suggestions on how to present the subject matter in such a formal languages course, which has traditionally been considered too difficult to be taught below the senior level, are also discussed.
A performance analysis of the gamma database machine
Authors: D. J. DeWitt, S. Ghanderaizadeh, D. Schneider
Venue: Proceedings of the 1988 ACM SIGMOD international conference on Management of data (1988)

This paper presents the results of an initial performance evaluation of the Gamma database machine. In our experiments we measured the effect of relation size and indices on response time for selection, join, and aggregation queries, and single-tuple updates. A Teradata DBC/1012 database machine of similar size is used as a basis for interpreting the results obtained. We also analyze the performance of Gemma relative to the number of processors employed and study the impact of varying the memory size and disk page size on the execution time of a variety of selection and join queries. We analyze and interpret the results of these experiments based on our understanding of the system hardware and software, and conclude with an assessment of the strengths and weaknesses of Gamma.
Estimating the number of test cases required to satisfy the all-du-paths testing criterion
Authors: J. Bieman, J. Schultz
Venue: Proceedings of the ACM SIGSOFT '89 third symposium on Software testing, analysis, and verification (1989)

The all-du-paths software testing criterion is the most discriminating of the data flow testing criteria of Rapps and Weyuker. Unfortunately, in the worst case, the criterion requires an exponential number of test cases. To investigate the practicality of the criterion, we develop tools to count the number of complete program paths necessary to satisfy the criterion. This count is an estimate of the number of test cases required. In a case study of an industrial software system, we find that in eighty percent of the subroutines the all-du-paths criterion is satisfied by testing ten or fewer complete paths. Only one subroutine out of 143 requires an exponential number of test cases.
Parameterized Ray-tracing
Authors: C. H. Séquin, E. K. Smyrl
Venue: Proceedings of the 16th annual conference on Computer graphics and interactive techniques (1989)

The construction and refinement of a computer graphics scene is unacceptably slow when using ray tracing. We introduce a new technique to speed up the generation of successive ray traced images when the geometry of the scene remains constant and only the light source intensities and the surface properties need to be adjusted. When the scene is first ray traced, an expression parameterized in the color of all lights and the surface property coefficients of all objects is calculated and stored for each pixel. Redisplaying a scene with a new set of lights and colors then consists of substituting values for the corresponding parameters and re-evaluating the expressions for the pixels. This parameter updating and redisplay takes only a few seconds, as compared to the many minutes or hours required to ray trace the entire scene again, but it uses much more memory and disk space. With suitable expression sharing, however, these storage needs can be reduced to an acceptable level.
On the first-order expressibility of recursive queries
Authors: S. S. Cosmadakis
Venue: Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1989)

A Datalog program is bounded iff it is equivalent to a recursion-free Datalog program. We show that, for some classes of Datalog programs, expressibility in first-order query languages coincides with boundedness. Our results imply that testing first-order expressibility is undecidable for binary programs, decidable for monadic programs, and complete for &Sgr;02.
N-Fold inspection: a requirements analysis technique
Authors: Johnny Martin, W. T. Tsai
Venue: Communications of the ACM (1990)

N-fold inspection uses traditional inspections of the user requirements document (URD) but replicates the inspection activities using N independent teams. A pilot study was conducted to explore the usefulness of N-fold inspection during requirements analysis. A comparison of N-fold inspection with other development techniques reveals that N-fold inspection is a cost-effective method for finding faults in the URD and may be a valid technique in the development of mission-critical software systems.
NETWORK 11.5 Tutorial: network modeling - without programming
Authors: W. J. Garrison
Venue: Proceedings of the 21st conference on Winter simulation (1989)

This tutorial will acquaint the reader with a powerful modelling tool which can dramatically reduce the amount of time it takes to simulate a computer system. The Network II.5 world view and the class of problems it addresses will be discussed. A summary of NETWORK II.5 capabilities will be presented. To tie the tutorial concepts together, an example of using NETWORK II.5 is included.
Design of Perimeter Estimators for Digitized Planar Shapes
Authors: J. Koplowitz, A. M. Bruchstein
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1989)

Measurement of perimeters of planar shapes from their digitized images is an important task of computer vision systems. A general methodology for the design of simple and accurate parameter estimation algorithms is described. It is based on minimizing the maximum estimation error for digitized straight edges over all orientations. Two perimeter estimators are derived and their performance is tested and digitized circles using computer simulations. The experimental results may be used to predict the performance of the algorithm on shapes with arbitrary contours of continuous curvature. The simulations also show that fast and accurate perimeter estimation is possible, even for objects that are small relative to pixel size.
Practical Cellular Dividers
Authors: Franco P. Preparata, Jean E. Vuillemin
Venue: IEEE Transactions on Computers (1990)

A discussion is presented of parallel division algorithms that can be classified among modified higher radix nonrestoring online division methods, where redundant representations are extensively utilized to speed up the operation. The network realizations of these algorithms are cellular, or even systolic with exclusively local control; they have both size (area) and time of O(n), where n is the length of the dividend representation. The same structures can also be used as a signed, digit-serial multiplier. When suitably equipped with some control and a few registers, the divider/multiplier brings remarkable performance to large modular arithmetic, RSA cryptography, and greatest common divisor computations. They are also of interest for the design of floating-point units and signal processing applications.
Maximum Alignment of Interchangeable Terminals
Authors: L.-S. Lin, S. Sahni
Venue: IEEE Transactions on Computers (1988)

The authors develop a linear algorithm to maximize the number of terminals aligned across a routing channel. It is assumed that the terminals in the cells on either side of the channel are interchangeable. This algorithm has application to the routing of PLAs and other circuits with interchangeable terminals.
Fast Algorithms for Low-Level Vision
Authors: R. Deriche
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

A recursive filtering structure is proposed that drastically reduces the computational effort required for smoothing, performing the first and second directional derivatives, and carrying out the Laplacian of an image. These operations are done with a fixed number of multiplications and additions per output point independently of the size of the neighborhood considered. The key to the approach is, first, the use of an exponentially based filter family and, second, the use of the recursive filtering. Applications to edge detection problems and multiresolution techniques are considered, and an edge detector allowing the extraction of zero-crossings of an image with only 14 operations per output element at any resolution is proposed. Various experimental results are shown.
Comparing software and hardware schemes for reducing the cost of branches
Authors: W. W. Hwu, T. M. Conte, P. P. Chang
Venue: ACM SIGARCH Computer Architecture News (1989)

Pipelining has become a common technique to increase throughput of the instruction fetch, instruction decode, and instruction execution portions of modern computers. Branch instructions disrupt the flow of instructions through the pipeline, increasing the overall execution cost of branch instructions. Three schemes to reduce the cost of branches are presented in the context of a general pipeline model. Ten realistic Unix domain programs are used to directly compare the cost and performance of the three schemes and the results are in favor of the software-based scheme. For example, the software-based scheme has a cost of 1.65 cycles/branch vs. a cost of 1.68 cycles/branch of the best hardware scheme for a highly pipelined processor (11-stage pipeline). The results are 1.19 (software scheme) vs. 1.23 cycles/branch (best hardware scheme) for a moderately pipelined processor (5-stage pipeline).
Marked event method in discrete event simulation
Authors: S. Li
Venue: Proceedings of the 21st conference on Winter simulation (1989)

In this paper, we develop a new method for sensitivity analysis of discrete event dynamic systems. The method is based on the observation that event lists under nominal system parameters can be shared by simulations with slightly perturbed parameters. Thus the simulation on different system configurations may be more efficient. The resulting algorithm is exact for Markovian systems, and approximate for non-Markovian systems. Experimental results are given to study the new algorithms.
Metamouse: specifying graphical procedures by example
Authors: David L. Maulsby, Ian H. Witten, Kenneth A. Kittlitz
Venue: Proceedings of the 16th annual conference on Computer graphics and interactive techniques (1989)

Metamouse is a device enabling the user of a drawing program to specify graphical procedures by supplying example execution traces. The user manipulates objects directly on the screen, creating graphical tools where necessary to help make constraints explicit; the system records the sequence of actions and induces a procedure. Generalization is used both to identify the key features of individual program steps, disregarding coincidental events; and to connect the steps into a program graph, creating loops and conditional branches as appropriate. Metamouse operates within a 2D click-and-drag drafting package, and incorporates a strong model of the relative importance of different types of graphical constraint. Close attention is paid to user interface aspects, and Metamouse helps the user by predicting and performing actions, thus reducing the tedium of repetitive graphical editing tasks.
Modified Matched Filter for Cloud Clutter Suppression
Authors: W.A.C. Schmidt
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

The least-mean-square (LMS) filter has been developed as an alternative to the classical matched filter (MF) to address the clutter-spectrum issue. However, the output of the MF and the LMS processes is dependent on the scene energy and marginally dependent on the filter signal shape. An approach referred to as the modified matched filter (MMF) is presented. The MMF is a product of the LMS filter and a nonlinear operator known as the inverse Euclidean distance. The nonlinear operator modifies the LMS filter to improve its sensitivity to signal shape. A comparison indicates the relative merit of including shape detection in the LMS clutter-suppression process. Infrared cloud scenes from the background measurements and analysis program (BMAP) were used to demonstrate the relative clutter-suppression performance for both the LMS and the MMF processes. A performance metric is developed to measure cloud clutter suppression quantitatively.
APL graphics and the associative machine
Authors: K. Soop
Venue: Proceedings of the international conference on APL (1987)

A limited extension of APL for binary relations is proposed, and it is shown that general graphic support falls out as a special case. The relational facility can be implemented as an associative machine which coexists with, and complements, the APL machine in a joint environment. The resulting system provides the basis for a robust and enduring solution to the issue of graphics in APL.
Performance-driven facial animation
Authors: Lance Williams
Venue: Proceedings of the 17th annual conference on Computer graphics and interactive techniques (1990)

As computer graphics technique rises to the challenge of rendering lifelike performers, more lifelike performance is required. The techniques used to animate robots, arthropods, and suits of armor, have been extended to flexible surfaces of fur and flesh. Physical models of muscle and skin have been devised. But more complex databases and sophisticated physical modeling do not directly address the performance problem. The gestures and expressions of a human actor are not the solution to a dynamic system. This paper describes a means of acquiring the expressions of real faces, and applying them to computer-generated faces. Such an "electronic mask" offers a means for the traditional talents of actors to be flexibly incorporated in digital animations. Efforts in a similar spirit have resulted in servo-controlled "animatrons," high-technology puppets, and CG puppetry [1]. The manner in which the skills of actors and puppetteers as well as animators are accommodated in such systems may point the way for a more general incorporation of human nuance into our emerging computer media.The ensuing description is divided into two major subjects: the construction of a highly-resoved human head model with photographic texture mapping, and the concept demonstration of a system to animate this model by tracking and applying the expressions of a human performer.
A hypothetical computer to simulate microprogramming and conventional machine language
Authors: Jerry E. Sayers, David E. Martin
Venue: ACM SIGCSE Bulletin (1988)

Microprogramming is no generally available to programmers because it may involve modification of a machine's native language. A hypothetical computer can provide a simulator for microprogramming projects and add considerably to one's understanding of the subject of microprogramming and the concept of a multilevel machine. The classical text, Structured Computer Organization by Andrew S. Tanenbaum, contains a design for such a hypothetical computer. This paper presents an implementation of this machine with a user interface to permit development of microprograms as well as development of programs at the conventional machine language programming level. The user interface is similar to that of MS-DOS's DEBUG program. In addition to providing the basis for projects in Computer Architecture and Computer Organization classes, the simulator is being used as a simplified hypothetical machine in a Systems Programming class for the development of assembler, linker, and loader projects.
Nondeterministic linear tasks may require substantially nonlinear deterministic time in the case of sublinear work space
Authors: Yuri Gurevich, Saharon Shelah
Venue: Proceedings of the twentieth annual ACM symposium on Theory of computing (1988)

Log-size Parabolic Clique Problem is a version of Clique Problem solvable in linear time by a log-space nondeterministic Turning machine. However, no deterministic machine (in a very general sense of this term) with sequential-access read-only input tape and work space n&sgr; solves Log-size Parabolic Clique Problem within time n1 + &tgr; if &sgr; + 2&tgr; < 1/2.