ppxscal/embedding_network huggingface dataset:
Coordinate representation of order types requires exponential storage
Authors: J. E. Goodman, R. Pollack, B. Sturmfels
Venue: Proceedings of the twenty-first annual ACM symposium on Theory of computing (1989)

We give doubly exponential upper and lower bounds on the size of the smallest grid on which we can embed every planar configuration of n points in general position up to order type. The lower bound is achieved by the construction of a widely dispersed &ldquo;rigid&rdquo; configuration which is then modified to one in general position by recent techniques of Sturmfels and White, while the upper bound uses recent results of Grigor'ev and Vorobjou on the solution of simultaneous inequalities. This provides a sharp answer to a question first posed by Chazelle.
A Noninvasive Architecture to Monitor Real-Time Distributed Systems
Authors: Jeffrey J. P. Tsai, Horng-Yuan Chen
Venue: Computer (1990)

The authors describe a model of real-time distributed computing systems, making the simplifying assumption that the system is dedicated. They present the hardware architecture, operation and implementation of the noninvasive monitoring system which consists of two major components: the interface module and the development module. The interface module can be considered as the front end of the monitoring system. The development module is the host computer for the interface module. The authors describe their approach to monitoring and demonstrate how it can be used to support the testing and debugging of real-time distributed computing systems. Essentially, the monitoring system supports different abstraction levels of monitoring according to application purposes. It can monitor process-level activities (e.g. procedure calls) as well as instruction-level activities (e.g. step-by-step instruction trace). A detailed description of process-level monitoring is given.
An O(N2) equivalence algorithm for fan-out free queries
Authors: P. Dublish, S. N. Maheshwari
Venue: Lecture notes in computer science on ICDT '88 (1988)

An equivalence algorithm for fan-out free queries, which form an untyped subclass of conjunctive queries, based on an extension of the implication graph technique is presented. This algorithm runs in O(n2) time where n is the size of the queries involved. This algorithm subsumes all known equivalence testing algorithms for various subclasses of fan-out free queries.
The Geometry of Differential Operators with Application to Image Processing
Authors: W. M. Krueger, K. Phillips
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1989)

A family of second-order nonlinear differential operators that are useful in building simple edge detectors is treated. The authors provide a uniform definition for these operators and describe their internal geometry. Based on their geometric analysis, they associate symbolic descriptors with the abstract edges defined by the operators. One of them, Q, is essentially the same operator that J.F. Canny used to define his two-dimensional simple edge detector. The authors give a parse tree for Q, which provides a complete analysis of its local geometry. The analysis shows that Q has a fondness for edges that lift to certain types of asymptotic curves. These include select straight line segments lying on the surface, inflections of mean curvature, and paths with constant rate of ascent. The methods are drawn largely from vector calculus and differential geometry. The authors illustrate their theoretical work with results obtained when Q was applied to image data that were interpolated with a B-spline.
Choosing group projects for advanced systems courses
Authors: Daniel Farkas
Venue: ACM SIGCSE Bulletin (1988)

This paper addresses the selection of projects for advanced information systems and software engineering courses and proposes criteria for group projects which gives students genuine real-world experience in the classroom. A curriculum for an advanced systems workshop is presented and a sample project with group interdependence and its prototyping under UNIX is described.
Recent trends in information systems law
Authors: B. K. Esposito, C. Walton, S. Walton
Venue: Proceedings of the ACM SIGCPR conference on Management of information systems personnel (1988)

Legal issues in the information systems area have been among the more active areas of the law. Even with this activity, legislation and the courts have lagged information technology. This recent activity effects the information systems manager. This article examines recent information legal issues in the areas of employment and personnel, corporate liability, and copyright.
Shortest division chains in imaginaryquadratic number fields
Authors: Heinrich Rolletschek
Venue: Journal of Symbolic Computation (1990)

Let O"d be the set of algebraic integers in an imaginary quadratic number field Q[@/d], d
The Cellar Principle of State Transition and Storage Allocation
Authors: F. L. Bauer
Venue: IEEE Annals of the History of Computing (1990)

The grammar of arithmetic formulas was the pilot example for developing parsing techniques for Chomsky grammars. It is shown how stacks were introduced and how they turned out to be powerful instruments within compilers by controlling state transitions at compile time and storage allocation at run time.
Penelope, an Ada verification system
Authors: D. Guaspari
Venue: Proceedings of the conference on Tri-Ada '89: Ada technology in context: application, development, and deployment (1989)

We are investigating the practical application of formal verification methods to Ada programs. Our motivation is the usual one: formal mathematical proof that a program is correct reduces the reliance on ad hoc testing procedures for quality assurance. In addition, the wide availability of Ada compilers makes it possible that formally specified and verified software could be widely used, which would be desirable in itself and would also provide practical data about its costs and benefits. Our specific goals: To accommodate a rich subset of (sequential) Ada&mdash;including packages, side effects, access types, exception-raising, and exception-handling&mdash;convenient for writing efficient programs. To explore ways of making verification more tractable and therefore more practical by exploiting strategies of interactive, incremental development of program and proof. Experiments are conducted on a running system prototype called Penelope. To provide the verification system with a formal mathematical basis.
Allocating Modules to Processors in a Distributed System
Authors: D. Fernandez-Baca
Venue: IEEE Transactions on Software Engineering (1989)

The author studies the complexity of the problem of allocating modules to processes in a distributed system to minimize total communication and execution costs. He shows that unless P=NP, there can be no polynomial-time epsilon -approximate algorithm for the problem, nor can there exist a local search algorithm that requires polynomial time per iteration and yields an optimum assignment. Both results hold even if the communication graph is planar and bipartite. On the positive side, it is shown that if the communication graph is a partial k-tree or an almost-tree with parameter k, the module allocation problem can be solved in polynomial time.
A Multiscanning Approach Based on Morphological Filtering
Authors: M. H. Chen, P. F. Yan
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1989)

It is argued that the mathematical morphology method seems to be more reasonable and powerful in studying certain multiscaling vision problems than the approach that uses derivatives of Gaussian-shaped filters of different sizes. To show the validity of this method, the authors concentrated on an application that involves forming scale-space image of a 2-D shape using morphological opening filtering. A proof is given to show that morphological opening filtering has a property of not introducing additional zero-crossings as one moves to a coarser scale. This is a different result from the conclusion by A.L. Yuille and T.A. Poggio that the Gaussian filter is the only filter with this property. In addition, opening filtering is computationaly simpler than the Gaussian filter.
Waveform relaxation for concurrent dynamic simulation of distillation columns
Authors: A. Skjellum, M. Morari, S. Nattisson
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications - Volume 2 (1989)

The need for cost-effective, high-speed computing is essential in many aspects of chemical engineering practice, notably for the simulation of large-scale dynamic systems. The arrival of powerful, highly concurrent message-passing multicomputers potentially offers such economical large-scale computing capability [13,14]. Development of appropriate, efficient algorithms which realize this potential must therefore become an important area of ongoing research and development in chemical engineering. Desired orders-of-magnitude speedup strongly motivates the use of novel algorithmic approaches for large-scale simulation. Initially, we are developing a simplified binary distillation simulation using the waveform relaxation paradigm [1-7]. Waveform relaxation has proven successful for the concurrent simulation of large-scale VLSI circuits [1-3,6,7] and is therefore a promising approach. Rather than an end in itself, however, we expect that results of this research effort will prove relevant to more general concurrent dynamic simulation including rigorous multicomponent distillation and chemical process flowsheeting. We describe the implementation effort (which generalizes the pre-existing CONCISEVLSI circuit simulator, [6]), the simplified distillation model, design issues and current status including a sketch of the underlying waveform relaxation algorithm and its realization. Elsewhere we report further observations as well as speedup results [15].
Conceptual foundations for computer documentation: new distinctions for a new er
Authors: D. Farkas
Venue: Proceedings of the 7th annual international conference on Systems documentation (1989)

Concepts are thoughts made clear and distinct by the distinctions we draw at their boundaries. The concept &ldquo;conifer&rdquo; comes about when we begin to make a specific distinction about the features of certain trees. If we cannot formulate such a distinction, we do not have the concept. As the computer industry changes, much depends on our ability to formulate new and relevant distinctions and to thereby refocus old concepts and make new ones possible. Otherwise, our overall understanding of our field will diminish and our day-to-day work will in subtle ways become less effective. As documentation specialists, our view of the computer industry is necessarily different from that of those who design systems, manufacture systems, or market systems. Thus, we need to carve up the universe in ways that are most useful for our work. At the same time, of course, we have to understand and use the distinctions made elsewhere in the industry. The purpose of this paper is to point out four traditional distinctions within the computer industry that are not highly serviceable to those engaged in documentation and to describe refinements upon or alternatives to those distinctions. The distinctions are as follows: Computer systems and noncomputer systems Computer hardware and software Documentation and interface Print and online documentation As we shall see, the distinction between computer hardware and software has always presented significant conceptual difficulties in the area of documentation. In the case of the other distinctions, the difficulties have come about or have been exacerbated by technological change.
Hardware differences in the 9373 and 9375 processors
Authors: Lawrence Curley, James Kuruts, John Myers
Venue: ACM SIGMICRO Newsletter (1988)

In order to have a broad range of performance in processors, more than one model must exist. A family of processors infers systems with enough commonality that a smaller model can be upgraded to a larger one with minimum effort by retaining as much of the existing hardware as possible. This paper describes the differences between the Models 20 and 40, which have basically the same internal engine, and the Model 60, which has additional hardware to give it improved performance. The paper begins with a description of what cache and TLBs (translation look-aside buffers) are, and explains how they affect the performance of a processor.
Using latent semantic analysis to improve access to textual information
Authors: S. T. Dumais, G. W. Furnas, T. K. Landauer, S. Deerwester, R. Harshman
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1988)

This paper describes a new approach for dealing with the vocabulary problem in human-computer interaction. Most approaches to retrieving textual materials depend on a lexical match between words in users' requests and those in or assigned to database objects. Because of the tremendous diversity in the words people use to describe the same object, lexical matching methods are necessarily incomplete and imprecise [5]. The latent semantic indexing approach tries to overcome these problems by automatically organizing text objects into a semantic structure more appropriate for matching user requests. This is done by taking advantage of implicit higher-order structure in the association of terms with text objects. The particular technique used is singular-value decomposition, in which a large term by text-object matrix is decomposed into a set of about 50 to 150 orthogonal factors from which the original matrix can be approximated by linear combination. Terms and objects are represented by 50 to 150 dimensional vectors and matched against user queries in this &ldquo;semantic&rdquo; space. Initial tests find this completely automatic method widely applicable and a promising way to improve users' access to many kinds of textual materials, or to objects and services for which textual descriptions are available.
Scope: automated generation of graphical interfaces
Authors: C. M. Beshers, S. Feiner
Venue: Proceedings of the 2nd annual ACM SIGGRAPH symposium on User interface software and technology (1989)

We describe the design and prototype implementation of Scope, a system that generates graphical user interfaces for applications programmed in C++. The programmer chooses application data objects and functions that define the capabilities of the interface. At runtime, an interface design component, implemented as a set of production system rules, transforms this semantic specification into an interface built using a window system, an associated user interface toolkit, and the hardware input devices available on the system. The rules match application requirements against a semantic description of the toolkit, selecting virtual devices for input, output, and layout. Thus, Scope uses design rules to create interfaces from high-level programming semantics that are customized both for the application and the run-time environment.
Using constraints to achieve stability in automatic graph layout algorithms
Authors: Karl-Friedrich Böhringer, Frances Newbery Paulisch
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: Empowering people (1990)

Automatic layout algorithms are commonly used when displaying graphs on the screen because they provide a &ldquo;nice&rdquo; drawing of the graph without user intervention. There are, however, a couple of disadvantages to automatic layout. Without user intervention, an automatic layout algorithm is only capable of producing an aesthetically pleasing drawing of the graph. User- or application-specified layout constraints (often concerning the semantics of a graph) are difficult or impossible to specify. A second problem is that automatic layout algorithms seldom make use of information in the current layout when calculating the new layout. This can also be frustrating to the user because whenever a new layout is done, the user's orientation in the graph is lost. This paper suggests using layout constraints to solve both of these problems. We show how user-specified layout constraints may be easily added to many automatic graph layout algorithms. Additionally, the constraints specified by the current layout are used when calculating the new layout to achieve a more stable layout. This approach allows a continuum between manual and automatic layout by allowing the user to specify how stable the graph's layout should be.
Diagnosis and Repair of Memory with Coupling Faults
Authors: M.-F. Chang, W. K. Fuchs, J. H. Patel
Venue: IEEE Transactions on Computers (1989)

The problem of diagnosis and spare allocation for random-access memory (RAM) with coupling faults is addressed. A number of spare allocation algorithms for RAM with row and column redundancy have recently been proposed. These procedures, however, have been restricted to repair stuck-at faults. The authors examine both diagnosis and repair of coupling faults in RAMs utilizing spare rows and columns. It is shown that a coupling fault is repaired if its coupling cell is replaced by utilizing a spare row or its coupled cell is replaced by utilizing a spare row or column. By specifying both the coupled cell and coupling cell, the amount of redundancy required to repair a given set of faults may be reduced. A diagnosis procedure for RAM is provided to locate stuck-at faults as well as coupling faults. A graph model is used to describe the repair of coupling faults. A repair procedure has been implemented to allocate rows and columns for repair.
Analysis and simulation of a fair queueing algorithm
Authors: A. Demers, S. Keshav, S. Shenker
Venue: Symposium proceedings on Communications architectures protocols (1989)

We discuss gateway queueing algorithms and their role in controlling congestion in datagram networks. A fair queueing algorithm, based on an earlier suggestion by Nagle, is proposed. Analysis and simulations are used to compare this algorithm to other congestion control schemes. We find that fair queueing provides several important advantages over the usual first-come-first-serve queueing algorithm: fair allocation of bandwidth, lower delay for sources using less than their full share of bandwidth, and protection from ill-behaved sources.
A Proof of Convergence for Two Parallel Jacobi SVD Algorithms
Authors: F. T. Luk, H. Park
Venue: IEEE Transactions on Computers (1989)

The authors consider two parallel Jacobi algorithms, due to R.P. Brent et al. (J. VLSI Comput. Syst., vol.1, p.242-70, 1985) and F.T. Luk (1986 J. Lin. Alg. Applic., vol.77, p.259-73), for computing the singular value decomposition of an n*n matrix. By relating the algorithms to the cyclic-by-rows Jacobi method, they prove convergence of the former for odd n and of the latter for any n. The authors also give a nonconvergence example for the former method for all even n¿4.
OROS: toward a type model for software development environments
Authors: W. R. Rosenblatt, J. C. Wileden, Alexander L. Wolf
Venue: Conference proceedings on Object-oriented programming systems, languages and applications (1989)

Three important goals of next generation software development environments (SDEs) are extensibility, integration and broad scope. Our work on OROS is predicated on the hypothesis that a type model, incorporated into an environment's object manager, can contribute to achieving those goals. This paper reports on an attempt at applying object-oriented typing concepts in the domain of software development environments. We believe that the result is a type model that has properties of interest both to software environment builders and also to builders and users of object-oriented systems in general.
Integrated information retrieval for law in a hypertext environment
Authors: E. Wilson
Venue: Proceedings of the 11th annual international ACM SIGIR conference on Research and development in information retrieval (1988)

A prototype information retrieval system for lawyers, Justus, has been developed on a Sun workstation to run in a Guide hypertext environment. The hypertext database is created automatically by Justus from machine readable versions of the ordinary printed texts, ideally the publisher's typesetting tapes. The database incorporates primary legal sources, such as statutes and cases, and secondary sources, such as textbooks and a dictionary. Initially, the lawyer may select any document in the system. From this initial document, he may access any other document, or part of any other document, to which reference is made. Reference selection is by a pointing device, such as a mouse. There is no limit on the number of selections that can be made, and no restrictions on the path through the system.
A Macroscopic Profile of Program Compilation and Linking
Authors: M. A. Linton, R. W. Quong
Venue: IEEE Transactions on Software Engineering (1989)

To profile the changes made to programs during development and maintenance, the authors have instrumented the 'make' utility that is used to compile and link programs. With minor modifications, they have used 'make' to find out how much time programmers spend waiting for compiling and linking, how many modules are compiled each time a program is linked, and the change in size of the compiled modules. Measurements show that most programs are relinked after only one or two modules are recompiled, and that over 90% of all recompilations yield object code that is less than 100 bytes larger in size. The authors are using these results to guide the design of an incremental programming environment, particularly with respect to an incremental linker.
Efficient synchronization primitives for large-scale cache-coherent multiprocessors
Authors: James R. Goodman, Mary K. Vernon, Philip J. Woest
Venue: ACM SIGARCH Computer Architecture News (1989)

This paper proposes a set of efficient primitives for process synchronization in multiprocessors. The only assumptions made in developing the set of primitives are that hardware combining is not implemented in the inter-connect, and (in one case) that the interconnect supports broadcast. The primitives make use of synchronization bits (syncbits) to provide a simple mechanism for mutual exclusion. The proposed implementation of the primitives includes efficient (i.e. local) busy-waiting for syncbits. In addition, a hardware-supported mechanism for maintaining a first-come first-serve queue of requests for a syncbit is proposed. This queueing mechanism allows for a very efficient implementation of, as well as fair access to, binary semaphores. We also propose to implement Fetch and Add with combining in software rather than hardware. This allows an architecture to scale to a large number of processors while avoiding the cost of hardware combining. Scenarios for common synchronization events such as work queues and barriers are presented to demonstrate the generality and ease of use of the proposed primitives. The efficient implementation of the primitives is simpler if the multiprocessor has a hardware cache-consistency protocol. To illustrate this point, we outline how the primitives would be implemented in the Multicube multiprocessor [GoWo88].
On Optimal Site Assignment for Relations in the Distributed Database Environment
Authors: Douglas W. Cornell, Philip S. Yu
Venue: IEEE Transactions on Software Engineering (1989)

In a distributed database environment, the site assignment of relations is a critical issue. When the joint operations in a query involve relations over multiple sites, the site to carry out the joint operation can have a significant impact on the performance. Based on the query descriptions and arrival frequency to each site, a methodology is developed to assign relations and determine joint sites simultaneously. The methodology first decomposes queries into relation steps and then makes site assignments based on either a linear integer programming technique to minimize the amount of intersystem communication while balancing resource utilizations across systems, or a heuristic technique to minimize average response time under similar resource constraints.