ppxscal/embedding_network huggingface dataset:
The effectiveness of computer graphics for decision support: meta-analytical integration of research findings
Authors: Mark I. H. Hwang, Bruce J. P. Wu
Venue: ACM SIGMIS Database (1991)

This research uses meta---analysis, a quantitative literature review technique, to integrate and combine the results fromseveral presentation format studies. The motivation behind this research is twofold: the conflicting research results found in the literature, and the lack of a cumulative body of knowledge. Meta---analysis is a research technique that provides a means for cumulating research findings across studies. In addition, meta-analysis can resolve differences found in previous studies by isolating the effect of moderator variables. This research found very strong evidence of the existence of one moderator variable, task complexity, which may have resulted in reported inconsistencies from prior presentation format research. Furthermore, an inverted "U---shaped" curve may explain the relationship between the effectiveness of graphs and task complexity. Specifically, using graphical data achieves better decision---making performance when the task is moderately complex. When the task complexity is either too low or too high, there is no performance difference between graphical and tabular presentation formats.
Investigations of the software testing coupling effect
Authors: A. Jefferson Offutt
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (1992)

Fault-based testing strategies test software by focusing on specific, common types of faults. The coupling effect hypothesizes that test data sets that detect simple types of faults are sensitive enough to detect more complex types of faults. This paper describes empirical investigations into the coupling effect over a specific class of software faults. All of the results from this investigation support the validity of the coupling effect. The major conclusion from this investigation is the fact that by explicitly testing for simple faults, we are also implicitly testing for more complicated faults, giving us confidence that fault-based testing is an effective way to test software.
Dependability Modeling for Multiprocessors
Authors: Chita R. Das, Jeffrey T. Kreulen, Matthew J. Thazhuthaveetil, Laxmi N. Bhuyan
Venue: Computer (1990)

A tutorial on dependability and performance-related dependability models for multiprocessors is presented. Multiprocessors are classified as having shared-memory or distributed-memory architectures, and some fundamental dependability modeling concepts. Reliability models based on four types of reliability evaluation techniques (terminal, multiterminal, task-based, and network reliability) are examined. The status of research efforts on performance-related dependability is discussed, and the models' effectiveness is illustrated with a few numerical examples. A brief survey of software packages for dependability computation in included.
Incremental Scanning and Parsing with Galaxy
Authors: John F. Beetem, Anne F. Beetem
Venue: IEEE Transactions on Software Engineering (1991)

The algorithms and techniques used in incremental scanning and parsing of the Galaxy language are presented. Incremental compilers, programming environments that feature instantaneous change processing as well as the execution time efficiency of compiled programs and code development using the Galaxy language are discussed. It is shown that the algorithms guarantee minimal rescanning and reparsing are space and time efficient and are easily adapted to any language of equivalent class, including such languages as C and Pascal.
SISAL versus FORTRAN: a comparison using the Livermore loops
Authors: David Cann, John Feo
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

The acquisition of parallel processors in the scientific community is increasing, but the difficulties of programming parallel machines persist. Two approaches have emerged: automatic parallelizing compilers for extant languages, and new languages professed to provide simpler and cleaner parallel programming models. Unfortunately, because of their semantics most new languages have acquired a reputation for inefficiency. This paper compares the performance of SISAL, an applicative language for parallel numerical computations, and FORTRAN using the Livermore Loops. Our intent is to show that applicative programs, when compiled using a set of powerful yet simple optimization techniques, can achieve sequential execution speeds comparable to FORTRAN, and automatically utilize conventional shared memory multiprocessors.
Integrating destructive assignment and lazy evaluation in the multiparadigm language G-2
Authors: John Placer
Venue: ACM SIGPLAN Notices (1992)

In order to design a broadly multiparadigm language, i.e., a language that directly supports several diverse programming paradigms, one must integrate a number of seemingly incompatible paradigmatic attributes. Among the most formidable of these antagonists are the time-independent and the time-dependent features of the diverse paradigms that are to be integrated into the language design. Although at some level these antagonists are inherently irreconcilable, finding an appropriate level of integration for such diverse elements can be a significant contribution to a broadly multiparadigm language design. In order to demonstrate this, we first briefly introduce the language G-2, the latest version of the multiparadigm language G. We focus on a new linguistic feature, called a block, that was introduced into G-2 in order to reconcile the facilities of destructive assignment and lazy evaluation. Finally we examine how the block supports many of the paradigms included in G-2 in a simple and direct manner.
Bayesian Estimation of Motion Vector Fields
Authors: Janusz Konrad, Eric Dubois
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

A stochastic approach to the estimation of 2D motion vector fields from time-varying images is presented. The formulation involves the specification of a deterministic structural model along with stochastic observation and motion field models. Two motion models are proposed: a globally smooth model based on vector Markov random fields and a piecewise smooth model derived from coupled vector-binary Markov random fields. Two estimation criteria are studied. In the maximum a posteriori probability (MAP) estimation, the a posteriori probability of motion given data is maximized, whereas in the minimum expected cost (MEC) estimation, the expectation of a certain cost function is minimized. Both algorithms generate sample fields by means of stochastic relaxation implemented via the Gibbs sampler. Two versions are developed: one for a discrete state space and the other for a continuous state space. The MAP estimation is incorporated into a hierarchical environment to deal efficiently with large displacements.
Semi-Distributed Load Balancing for Massively Parallel Multicomputer Systems
Authors: Ishfaq Ahmad, Arif Ghafoor
Venue: IEEE Transactions on Software Engineering (1991)

A semidistributed approach is given for load balancing in large parallel and distributed systems which is different from the conventional centralized and fully distributed approaches. The proposed strategy uses a two-level hierarchical control by partitioning the interconnection structure of a distributed or multiprocessor system into independent symmetric regions (spheres) centered at some control points. The central points, called schedulers, optimally schedule tasks within their spheres and maintain state information with low overhead. The authors consider interconnection structures belonging to a number of families of distance transitive graphs for evaluation, and, using their algebraic characteristics, show that identification of spheres and their scheduling points is in general an NP-complete problem. An efficient solution for this problem is presented by making exclusive use of a combinatorial structure known as the Hadamard matrix. The performance of the proposed strategy has been evaluated and compared with an efficient fully distributed strategy through an extensive simulation study. The proposed strategy yielded much better results.
Computing transitive closures of multilevel relations
Authors: Bhavani Thuraisingham
Venue: ACM SIGMOD Record (1990)

Recently many attempts have been made to implement recursive queries. Such queries are essential for the new generation intelligent database system applications. Much of the effort in recursive queries is focussed on transitive closure queries which are of practical significance. None of the work described investigates recursive query processing in secure database management systems. In this paper we propose centralized and distributed algorithms for implementing transitive closure queries for multilevel secure relational database management systems.
Sequentiality in orthogonal term rewriting systems
Authors: Jan Willem Klop, Aart Middeldorp
Venue: Journal of Symbolic Computation (1991)

For orthogonal term rewriting systems Q. Huet and J.-J. Levy have introduced the property of 'strong sequentiality'. A strongly sequential orthogonal term rewriting system admits an efficiently computable normalizing one-step reduction strategy. As shown by Huet and Levy, strong sequentiality is a decidable property. In this paper we present an alternative analysis of strongly sequential term rewriting systems, leading to two simplified proofs of the decidability of this property. We also compare some related notions of sequentiality that recently have been proposed.
Simulation of real-time embedded systems
Authors: Gabi Leshem
Venue: ACM SIGSIM Simulation Digest (1992)

This paper proposes an architecture simulator as an important addition to CASE tools, to be used during various design stages of real-time embedded systems. The architecture simulator is intended for simulating the behavior of the system based on partial information available at the beginning of the design process. The simulator in conjunction with a CASE tool can minimize the damage caused by improper design decisions made at the early stages of the design.
A class of convex programs with applications to computational geometry
Authors: Martin Dyer
Venue: Proceedings of the eighth annual symposium on Computational geometry (1992)

We consider the solution of convex programs in a small number of variables but large number of constraints, where all but a small number of the constraints are linear. We develop a general framework for obtaining algorithms for these problems which run in time linear in the number of constraints. We give an application to computing minimum spanning ellipsoids in fixed dimension.
VirtualClock: a new traffic control algorithm for packet-switched networks
Authors: Lixia Zhang
Venue: ACM Transactions on Computer Systems (TOCS) (1991)

One of the challenging research issues in building high-speed packet-switched networks is how to control the transmission rate of statistical data flows. This paper describes a new traffic control algorithm, VirtualClock, for high-speed network applications. VirtualClock monitors the average transmission rate of statistical data flows and provides every flow with guaranteed throughput and low queueing delay. It provides firewall protection among individual flows, as in a TDM system, while retaining the statistical multiplexing advantages of packet switching. Simulation results show that the VirtualClock algorithm meets all its design goals.
Triangulating polygons without large angles
Authors: Marshall Bern, David Dobkin, David Eppstein
Venue: Proceedings of the eighth annual symposium on Computational geometry (1992)

We show how to triangulate an n-vertex polygonal region&mdash;adding extra vertices as necessary&mdash;with triangles of guaranteed quality. Using only O(n) triangles, we can guarantee that the smallest height (shortest dimension) of a triangle is approximately as large as possible. Using O(n log n) triangles, we can also guarantee that the largest angle is no greater than 150&deg;. Finally we give a nonobtuse triangulation algorithm for convex polygons that uses O(n1.85) triangles.
Use of genetic algorithms for optimization in digital control of dynamic systems
Authors: Rajeshwar Prasad Srivastava
Venue: Proceedings of the 1992 ACM annual conference on Communications (1992)

This paper presents a method to optimize proportional-integral-derivative (PID) control parameters, given a discrete model of the controlled process. This method is based on Holland's genetic algorithm (GA). It does not require a mathematical model of the controller to represent its dynamic behavior. It gives a solution that is not only optimal but also meets engineering constraints. Genetic algorithms do a global search without derivatives for points in a multi-dimensional search space. This method works for non-linear as well as linear systems. The objective function of the GA is based on the integrated product of time and absolute error (ITAE). The performance of the GA is compared to that of the other optimization methods. The results show that it is simple and effective.
Slowing propagation error caused by finite register sizes in unstable systems
Authors: Sandra J. Cynar
Venue: ACM SIGNUM Newsletter (1990)

When doing simulations one of the worst problems that can occur is an unstable system model. These unstable models often appear in systems identification problems where the system has a non-minimum phase model. This situation leads to an unstable inverse system. The instability means that the system model must be redefined, even though the non-minimum phase model is most accurate. Or a method for deconvolution will be chosen that assumes the system is minimum phase, even though it is not. Often these inaccurate fixes or assumptions are not necessary. Cases where short strings of data are being processed can use the unstable inverse and produce good results. By using the superposition feature of linear systems it is possible to increase the useful run time of these unstable deconvolvers.
Enhancing the performance of a dynamically partitionable bus network using a graph coloring algorithm
Authors: Tai-Kuo Woo, Stanley Y. W. Su, Richard Newman-Wolfe
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

An efficient dynamic graph traversal algorithm is used to identify non-conflicting requests and to allocate network resources in a dynamically partitionable bus network (DPBN). A special processor receives from the control computer of a partitionable bus network an adjacency matrix which indicates conflicts among requests. It applies the dynamic graph traversal algorithm and returns the identified non-conflicting requests to the control computer. The control computer then physically partitions the network into a number of subnetworks for processing non-conflicting requests in parallel. The results of performance evaluation show a forty percent decrease of network delay as compared with a fully utilized, but unpartitioned local area network.
A deterministic parallel algorithm for planar graphs isomorphism
Authors: Hillel Gazit
Venue: Proceedings of the 32nd annual symposium on Foundations of computer science (1991)

A deterministic parallel algorithm for determining whether two planar graphs are isomorphic is presented. The algorithm needs O(log n) separators that have to be computed one after the other. The running time is T=O(log/sup 3/ n) time for finding separators, and the processors count is n/sup 1.5/ log n/T. It is also shown that every planar graph has a separator, and a parallel algorithm for finding the separator is given.
Shapes Recognition Using the Straight Line Hough Transform: Theory and Generalization
Authors: Derek C. W. Pao, Hon F. Li, R. Jayakumar
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

A shape matching technique based on the straight line Hough transform (SLHT) is presented. In the theta - rho space, the transform can be expressed as the sum of the translation term and the intrinsic term. This formulation allows the translation, rotation, and intrinsic parameters of the curve to be easily decoupled. A shape signature, called the scalable translation invariant rotation-to-shifting (STIRS) signature, is obtained from the theta - rho space by computing the distances between pairs of points having the same theta value. This signature is invariant to translation and can be easily normalized, and rotation in the image space corresponds to circular shifting of the signature. Matching two signatures only amounts to computing a 1D correlation. The height and location of a peak (if it exists) indicate the similarity and orientation of the test object with respect to the reference object. The location of the test object is obtained, once the orientation is known, by an inverse transform (voting) from the theta - rho space to the x-y plane.
Realizing a video environment: EuroPARC's RAVE system
Authors: William Gaver, Thomas Moran, Allan MacLean, Lennart Lövstrand, Paul Dourish, Kathleen Carter, William Buxton
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

At EuroPARC, we have been exploring ways to allow physically separated colleagues to work together effectively and naturally. In this paper, we briefly discuss several examples of our work in the context of three themes that have emerged: the need to support the full range of shared work; the desire to ensure privacy without giving up unobtrusive awareness; and the possibility of creating systems which blur the boundaries between people, technologies and the everyday world.
Communicative technology and the emerging global curriculum
Authors: Robert P. Taylor
Venue: ACM SIGCUE Outlook (1991)

In the 1910 rural community where my father was growing up, his teachers did not train him to become the pilot and aviation pioneer he later became. Airplanes had barely been invented and few if any teachers probably had any idea what skills one might need to fly them. Their curriculum certainly didn't reflect the world shrinking changes that aviation was about to bring. Similarly, in the 1940 rural community where I was growing up, my teachers did not train me to become the pioneer in computing and education which I later became. Computers were virtually unheard of by teachers and they certainly had no idea what thinking skills would be necessary for designing software. And, once again, the curriculum didn't reflect the changes that computers were about to launch.
Paradoxes in parallel processing (abstract)
Authors: Dietrich Fischer
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

Intuition suggests that when a computation is moved from a single processor to n parallel processors, the speedups possible range from a factor of n for a completely parallelizable procedure to no speedup at all for a strictly sequential procedure. It is shown, however, that in some cases speedups greater than n can be achieved, while in other cases the use of parallel processors would cause a slowdown. Some earlier published claims of superlinear speedups are shown to be false, due only to inefficiency of the single-processor algorithm. However, it is proven that if internal memory is a constraint, superlinear speedups are indeed possible, even for the most efficient algorithm. On the other hand, if the exchange of data between processors is sufficiently time-consuming, it can be faster to perform an algorithm on a single processor. There also exist intermediate speedups, close to linear (in the order of n/log2n) for certain vector operations, and an extremely low speedup in the order of log2n for some binary search procedures.
Minimalism reconsidered: should we design documentation for exploratory learning?
Authors: Thomas R. Williams, David K. Farkas
Venue: ACM SIGCHI Bulletin (1992)

During the past decade, few efforts aimed at the articulation of new computer documentation models have inspired as much interest within the documentation community as has John Carroll's formulation of the tenets of "minimalism." In our experience, however, minimalism is often incorrectly understood by practitioners simply as a prescription for brevity. Minimalism is, in fact, more complex than this. In "The Minimal Manual" (1987--88) Carroll and his coauthors suggest that minimalism comprises four characteristics: (1) brevity (or perhaps conciseness), (2) focus on real tasks, (3) support of error recognition and recovery efforts, and (4) adoption of an instructional philosophy termed "guided exploration."
Computation of large-scale constrained matrix problems: the splitting equilibration algorithm
Authors: Anna Nagurney, Alexander Eydeland, Dae-Shik Kim
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

The Constrained Matrix problem is a core problem in numerous applications in the social and economic sciences, including: the estimation of input-output tables, trade tables, and social/national accounts, the projection of migration flows over space and time, the treatment of census data, the analysis of political voting patterns, and the estimation of contingency tables. In this paper we introduce a general parallelizable computational method called the Splitting Equilibration Algorithm for solving the entire class of constrained matrix problems. Since the constrained matrix approach has become a standard modelling tool among researchers and practitioners, the need for a unifying, robust, and efficient computational procedure is of practical importance. The empirical performance of the algorithm is then investigated on the largest quadratic constrained matrix problems reported to date using the IBM 3090-600E at the Cornell National Supercomputer Facility in a serial and in a parallel environment.
Controlling user interface objects through pre- and postconditions
Authors: Daniel F. Gieskens, James D. Foley
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

We have augmented user interface objects (i.e. windows, menus, buttons, sliders, ets.) with preconditions that determine their visibility and their enabled/disabled status and postconditions that are asserted when certain actions are performed on the object. Postconditions are associated with each functionally different action on the object. Attaching pre- and postconditions to interface objects provides several useful features, such as selective enabling of controls, rapid prototyping, and automatic generation of explanations and help text.
The CAEDE performance analysis tool
Authors: C. M. Woodside, E. M. Hagos, E. Neron, R. J. A. Buhr
Venue: Proceedings of the first international symposium on Environments and tools for Ada (1991)

A performance analysis tool which has been built into the CAEDE environment for design of Ada software is described. In the 'software CAD' philosophy of CAEDE this could be one of several analysis tools to be used on design, before generating application code. The analyzer has a practical interface for software designers and computes system throughputs for various design options and processor speeds and allocations, as well as finding bottlenecks and task utilizations, etc. Both an early version of these calculations, which is performed in the distribution version CAEDE1.5, and a more advanced research version are described.
A new simple and efficient antialiasing with subpixel masks
Authors: Andreas Schilling
Venue: Proceedings of the 18th annual conference on Computer graphics and interactive techniques (1991)

Antialiasing of edges is often performed with the help of subpixel masks that indicate which parts of the pixel are covered by the object that has to be drawn. For this purpose, subpixel masks have to be generated during the scan conversion of an image. This paper introduces a new algorithm for creating subpixel masks that avoids some problems of traditional algorithms, like aliasing of high frequencies or blinking of small moving objects. The new algorithms can be implemented by lookup tables that make use of the inherent symmetry of the algorithm. The results are compared with conventional supersampling. A hardware implementation is described.