ppxscal/embedding_network huggingface dataset:
Optimization of large join queries
Authors: Arun Swami, Anoop Gupta
Venue: Proceedings of the 1988 ACM SIGMOD international conference on Management of data (1988)

We investigate the problem of optimizing Select&mdash;Project&mdash;Join queries with large numbers of joins. Taking advantage of commonly used heuristics, the problem is reduced to that of determining the optimal join order. This is a hard combinatorial optimization problem. Some general techniques, such as iterative improvement and simulated annealing, have often proved effective in attacking a wide variety of combinatorial optimization problems. In this paper, we apply these general algorithms to the large join query optimization problem. We use the statistical techniques of factorial experiments and analysis of variance (ANOVA) to obtain reliable values for the parameters of these algorithms and to compare these algorithms. One interesting result of our experiments is that the relatively simple iterative improvement proves to be better than all the other algorithms (included the more complex simulated annealing). We also find that the general algorithms do quite well at the maximum time limit.
An Efficient Uniform Cost Algorithm Applied to Distance Transforms
Authors: B. J. Verwer, P. W. Verbeek, S. T. Dekker
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1989)

The uniform-cost algorithm is a special case of the A*-algorithm for finding the shortest paths in graphs. In the uniform-cost algorithm, nodes are expanded in order of increasing cost. An efficient version of this algorithm is developed for integer cost values. Nodes are sorted by storing them at predefined places (bucket sort), keeping the overhead low. The algorithm is applied to general distance transformation. A constrained distance transform is an operation which calculates at each pixel of an image the distance to the nearest pixel of a reference set, distance being defined as minimum path length. The uniform-cost algorithm, in the constrained case, proves to be the best solution for distance transformation. It is fast, the processing time is independent of the complexity of the image, and memory requirements are moderate.
APL and GDDM - a high performance toolkit
Authors: D. Bowman
Venue: ACM SIGAPL APL Quote Quad (1989)

Performance of APL applications is an important consideration; especially when it can be achieved without compromising development time and maintainability.This paper explores some aspects of creating a high-performance toolkit for APL2-based applications using IBM's Graphical Data Display Manager (GDDM) software to provide the user interface. The performance achieved by these tools is considerably greater than that given by use of IBM's own workspaces distributed with the APL2 product, but the resulting application code is equally comprehensible and easy to write.Applications developed using these tools have provided performance equal to (or better than) equivalent applications coded in FORTRAN and have extended the domain of effective APL use.The paper makes no attempt to describe GDDM except in the broadest sense; it deals only with how it can be accessed from an APL application.
Opportunities for system and user features in a new APL interpreter
Authors: R. F. Hobson, J. D. Hoskin, R. W. Spilsbury
Venue: ACM SIGAPL APL Quote Quad (1989)

SAM I (Structured Architecture Machine) is the prototype of a new VLSI chip set based computer. SAM was designed with High-Level Language interpretation and parallel processing in mind. SAM's first language is a subset of APL. Our paper introduces the SAM I architecture and discusses some unique opportunities for APL implementation made possible by this architecture.
Design of a browsing interface for information retrieval
Authors: R. Godin, C. Pichet, J. Gecsei
Venue: ACM SIGIR Forum (1989)

In conventional Boolean retrieval systems, users have difficulty controlling the amount of output obtained from a given query. This paper describes the design of a user interface which permits gradual enlargement or refinement of the user's query by browsing through a graph of term and document subsets. This graph is obtained from a lattice automatically generated from the usual document-term relation. The major design features of the proposed interface are the integration of menu, fill-in the blank and direct manipulation modes of interaction within the &ldquo;fisheye view&rdquo; [Furnas, 1986] paradigm. A prototype user interface incorporating some of these ideas has been implemented on a microcomputer. The resulting interface is well adapted to various kinds of users and needs. More experienced users with a particular subject in mind can directly specify a query which results into a jump to a particular vertex in the graph. From there, the user can refine his initial query by browsing through the graph from that point on. On the other hand, casual users without any prior knowledge of the contents of the system or users without any particular subject in mind can freely navigate through the graph without ever specifying any query.
Apologizing versus asking permission: optimistic concurrency control for abstract data types
Authors: M. Herlihy
Venue: ACM Transactions on Database Systems (TODS) (1990)

An optimistic concurrency control technique is one that allows transactions to execute without synchronization, relying on commit-time validation to ensure serializability. Several new optimistic concurrency control techniques for objects in decentralized distributed systems are described here, their correctness and optimality properties are proved, and the circumstances under which each is likely to be useful are characterized. Unlike many methods that classify operations only as Reads or Writes, these techniques systematically exploit type-specific properties of objects to validate more interleavings. Necessary and sufficient validation conditions can be derived directly from an object's data type specification. These techniques are also modular: they can be applied selectively on a per-object (or even per-operation) basis in conjunction with standard pessimistic techniques such as two-phase locking, permitting optimistic methods to be introduced exactly where they will be most effective. These techniques can be used to reduce the algorithmic complexity of achieving high levels of concurrency, since certain scheduling decisions that are NP-complete for pessimistic schedulers can be validated after the fact in time, independent of the level of concurrency. These techniques can also enhance the availability of replicated data, circumventing certain tradeoffs between concurrency and availability imposed by comparable pessimistic techniques.
SASHA: the automatic generation of rule-based diagnostic expert systems
Authors: Anna Stein
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

SASHA is a model-driven application shell which generates expert systems for fault isolation and repair in complex electronic systems. SASHA incorporates an expert system shell and a knowledge acquisition tool into a unique mechanism that elicits data directly from the domain expert and outputs a rule-based diagnostic expert system. SASHA employs causal-model and rule-based representations. It uses a causal model to identify the structure, behavior and relation of a domain object. It uses rules to direct the diagnostic problem solver. SASHA's initial knowledge base consists of a domain independent generalized model of the system under analysis. This underlying model drives knowledge acquisition and the consequent generation of an expert system. SASHA introduces a new concept of Pattern Rules, which are a generalized skeleton of the diagnostic problem solver. During diagnosis, when applied to the domain specific Structural Knowledge base, Pattern Rules dynamically instantiate the actual domain rules. Based on the Pattern Rules notion, three types of rule base organization are proposed and analyzed: Fully Patternized Organization (FPO), Partly Patternized Organization (PPO) and Customized Domain-specific Organization (CDO).
A routing architecture for very large networks undergoing rapid reconfiguration
Authors: J. M. Synder
Venue: ACM SIGCOMM Computer Communication Review (1989)

A routing architecture is described for very large communications networks with greater than 10,000 routing nodes and 100,000 end nodes. This architecture, called the Traveler Architecture, is designed to be independent of network configuration and to be robust even under conditions of rapid reconfiguration. Traveler is an extension of the ISO routing protocols. The Traveler architecture is designed to work with traffic characteristic of existing large networks, such as the Internet. While Traveler does not require a particular routing algorithm, it is designed to work in conjunction with families of distributed routing algorithms. Because Traveler is based on the paradigm of a human traveler, it attempts to use non-deterministic and heuristic methods rather than purely algorithmic methods to determine high quality routes between two points. Traveler builds on the Landmark and Area routing architectures.
IBM France
Authors: J. Vernay
Venue: IEEE Annals of the History of Computing (1989)

This article focuses on the birth of the IBM France company in 1914; the proposal its directors made to buy out Bull, its main competitor; the second world war and the obstacles the company had to surmount. It also describes the opening of a scientific computing center, the arrival of the IBM 650, and the creation of the military applications department. Finally, it deals with some challenges with which IBM France was confronted during the last 20 years, most of them connected with the nationality of ifs parent company and the very nature of computing itself. This article underlines particularly its distinctive spirit that stems from the genuine code of conduct T. J. Watson gave its members.
A correction of the termination conditions of the Henschen-Naqvi technique
Authors: David A. Briggs
Venue: Journal of the ACM (JACM) (1990)

Henschen and Naqvi described a technique for translating queries on recursively defined relations of a Datalog database into iterative programs that invoke a query processor for conventional select-project-join queries of the relational algebra. Although the technique has been cited as one of the most efficient available, it will in some cases fail to produce all answers defined by the usual semantics for such databases. The technique is reviewed, a recursive query is exhibited where it fails, the cause of failure is noted, and a correction is described. A graphical representation of the computation based on a formal representation of rule expansions is employed.
The symbolic hyperplane transformation for recursively defined arrays
Authors: M. B. Gokhale, T. C. Torgersen
Venue: Proceedings of the 1988 ACM/IEEE conference on Supercomputing (1988)

This paper describes a restructuring transformation which can be used to parallelize recurrence relations. The transformation is based on the hyperplane (or wavefront) method, but extends the applicability of the method to irregularly-structured recurrences. We assume that the time of computation of an array element is a linear combination of its indices, and we use a variation of the simplex method to seek a succession of hyperplanes along which array elements can be computed concurrently. Portions of the work reported here have been implemented in the PS automatic program generation system.
Merging and Sorting Networks with the Topology of the Omega Network
Authors: G. Bilardi
Venue: IEEE Transactions on Computers (1989)

A class of comparator networks obtained from the omega permutation network by replacing each switch with a comparator exchanger of arbitrary direction is considered. These networks are all isomorphic to each other, have merging capabilities, and can be used as building blocks of sorting networks in ways different from the standard merge-sort scheme. It is shown that the bitonic and balanced mergers are members of the class. These two networks were not previously known to be isomorphic.
TRAM: A Design Methodology for High-Performance, Easily Testable, Multimegabit RAMs
Authors: N. T. Jarwala, D. K. Pradhan
Venue: IEEE Transactions on Computers (1988)

An architecture is proposed for multimegabit dynamic RAMs (random-access memories) that achieves higher testability and performance than the conventional four-quadrant RAMs. Applying the principle of divide and conquer, the RAM is partitioned into modules, each appearing as the leaf node of a binary interconnect network. Such a network carries the address/data/control bus, permitting the nodes to communicate among themselves as well as with the outside world. This architecture is shown to be easily testable. Parallelism in testing and partial self-test result in a large savings of testing time; the savings is independent of the test algorithm used. Unlike other testability schemes, this approach promises improved performance with only a small increase in chip area. It is also shown that the architecture is easily partionable and restructurable, with potential for yield and reliability improvement.
A deterministic algorithm for sparse multivariate polynomial interpolation
Authors: Michael Ben-Or
Venue: Proceedings of the twentieth annual ACM symposium on Theory of computing (1988)

An efficient deterministic polynomial time algorithm is developed for the sparse polynomial interpolation problem. The number of evaluations needed by this algorithm is very small. The algorithm also has a simple NC implementation.
Polynomial decomposition algorithms
Authors: Dexter Kozen, Susan Landau
Venue: Journal of Symbolic Computation (1989)

We examine the question of when a polynomial f over a commutative ring has a nontrivial functional decomposition f=g^o h. Previous algorithms are exponential-time in the worst case, require polynomial factorization, and only work over fields of characteristic 0. We present an O(n^2)-time algorithm, where r is the degree of g. We also show that the problem is in NC. The algorithm does not use polynomial factorization, and works over any commutative ring containing a multiplicative inverse of r. Finally, we give a new structure theorem that leads to necessary and sufficient algebraic conditions for decomposibility over any field. We apply this theorem to obtain an NC algorithm for decomposing irreducible polynomials over finite fields, and a subexponential algorithm for decomposing irreducible polynomials over any field admitting efficient polynomial factorization.
Automatic generation of graphic displays of data structures through a preprocessor
Authors: Moshe Augenstein, Yedidyah Langsam
Venue: ACM SIGCSE Bulletin (1988)

Recent attention has been given to graphic display routines that allow the programmer to observe the effects of applications programs on various data structures. Much of the work reported in the literature has involved the animation of specific algorithms and has necessitated manual effort by programmers on an application by application basis. Results of initial work in developing a general purpose tool for the display of data structures have already been published. In order to make the tool more widely used and more flexible it is necessary that some type of automatic processing be provided to allow for the generation of the graphic display routines themselves. Initial work in this area and further avenues of research are discussed.
A theory of organization
Authors: H. Von Issendorff
Venue: ACM SIGPLAN Notices (1990)

The theory of organization deals with the representation and treatment of processing structures and their realization. It offers an algebra, which in particular is qualified for a unified description of soft- and hardware. The term replacement rules coming along with the algebra allow to change a processing structure in a variety of ways. In particular, there are order changing rules allowing to generate any representation between the minimum order of dataflow and the maximum order of a sequence. Moreover, conversion rules can be specified for the transformation of conventional programming languages into the (language of the) algebra. The same is possible for the conversion of Boolean algebra. Finally, a circuit description language can be derived from the algebra, which seems to be well suited for VLSI-layout. Part 1 of this paper covers a general introduction to the subject and the notions, the relations, and the algebra on which the theory of organization is based. Part 2 deals with nondeterminism and communicating processes, presents the conversion rules for a subset of Pascal and for Boolean expressions and introduces the circuit description language.
Quartic Beta-splines
Authors: Barry Joe
Venue: ACM Transactions on Graphics (TOG) (1990)

Quartic Beta-splines have third-degree arc-length or geometric continuity at simple knots and are determined by three &bgr; or shape parameters. We present a general explicit formula for quartic Beta-splines, and determine and illustrate the effects of varying the &bgr; parameters on the shape of a quartic Beta-spline curve. We show that quartic (and higher degree) rational Beta-splines with arc-length continuity satisfy the same continuity conditions as (nonrational) Beta-splines. We also show that the torsion continuous spline curves presented by Boehm ("Smooth Curves and Surfaces.&rdquo; In Geometric Modeling: Algorithms and New Trends, G. E. Farin, Ed. SIAM, Philadelphia, Pa., 1987, pp. 175-184.) are equivalent to nonrational quartic Beta-spline curves, and determine the relationship between the shape parameters for the two types of curves. Finally, we present an algorithm for inserting a new knot and determining the refined control polygon.
Distributed Ada real-time kernel (DARK)
Authors: J. Bamberger
Venue: Proceedings of the conference on TRI-Ada '88 (1989)

The DARK Project proposes one solution to the problem of using Ada in distributed, real-time, embedded applications - one that can readily be accomplished in the near term. This alternative returns explicit control of scheduling to the application implementor and provides a uniform communication mechanism for supporting distributed processors or a single processor. Other difficult areas, such as fault tolerance and multi-level security, are not directly addressed in the Kernel definition. We have, however, examined our primitives in light of these and other equally demanding issues, and we believe the Kernel definition to be extensible enough to accommodate future development in these areas. Our goal is to provide a viable paradigm of near-term support to a wide number of real-time embedded applications currently being required to use Ada for implementation. We believe that the application builders, not compiler vendors, not language designers, know best the system-level behavior required for their programs. We believe that standardization of such behavior should be provided via a library package interface under the control of the application implementor, not via modifications to the Ada language. We believe our strategy and Kernel definition provide this kind of support.
Evaluation of retransmission strategies in a local area network environment
Authors: A. Mukherjee, L. H. Landweber, J. C. Strikwerda
Venue: Proceedings of the 1989 ACM SIGMETRICS international conference on Measurement and modeling of computer systems (1989)

We present an evaluation of retransmission strategies over local area networks. Expressions are derived for the expectation and the variance of the transmission time of the go-back-n and the selective repeat protocols in the presence of errors. These are compared to the expressions for blast with full retransmission on error (BFRE) derived by Zwaenepoel [Zwa 85]. We conclude that go-back-n performs almost as well as selective repeat and is very much simpler to implement while BFRE is stable only for a limited range of messages sizes and error rates. We also present a variant of BFRE which optimally checkpoints the transmission of a large message. This is shown to overcome the instability of ordinary BFRE. It has a simple state machine and seems to take full advantage of the low error rates of local area networks. We further investigate go-back-n by generalizing the analysis to an upper layer transport protocol, which is likely to encounter among other things, variable delays due to protocol overhead, multiple connections, process switches and operating system scheduling priorities.
A periodic Ada control kernel (PACK)
Authors: J. Ellis
Venue: Proceedings of the conference on Tri-Ada '89: Ada technology in context: application, development, and deployment (1989)

Numerous sources have questioned Ada's sufficiency in efficiently handling systems with predominantly periodic processes, especially when hard deadline scheduling is required. Several possible implementations have been suggested to address this problem. This paper describes a dual MIL-STD-1750A cockpit digital map display system which uses a Periodic Ada Control Kernel (PACK) to directly control execution of numerous periodic processes written in Ada. The PACK runs over the normal Ada Runtime System and controls a relatively large number of concurrently executing periodic (and aperiodic) procedures and provides a more direct interface to Ada-coded Interrupt Service Routines.
Diagnosing electronics systems by integrating models of normal and abnormal functioning
Authors: Scott Bublin, R. L. Kashyap
Venue: Proceedings of the 2nd international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1989)

Current approaches to diagnosis cannot handle novel situations and are inefficient in that they require excessive amounts of test data to isolate a fault. This paper presents a problem-solving method that combines an experientially-based abnormal model of device operation with a functionality-based model of normal operation. The CONSOLIDATE system has been constructed in SMALLTALK-80, and an television diagnosis application has been developed.
Local and global structuring of computer mediated communication: developing linguistic perspectives on CSCW in cosmos
Authors: John Bowers, John Churcher
Venue: Proceedings of the 1988 ACM conference on Computer-supported cooperative work (1988)

This paper is concerned with the development of a language/action perspective in the Cosmos project. We emphasize the importance of seeing cooperative work in terms of participants' communicative actions. In contrast to some explorations of speech act theory, we argue that communicative actions should be seen as essentially embedded in dialogical contexts. In particular, we attempt to show the relevance of concepts derived from the analysis of actually occurring conversations, for computer mediated communication in general and cooperative work in particular. We distinguish between local and global structuring of communication and argue that many group working situations combine both sorts. These observations have influenced our work in the Cosmos project on the design of a structure definition language (SDL) by means of which users can configure their computer mediated communication environment. We describe SDL and show how its interpretation is influenced by our conversation analytic approach. We illustrate our arguments with an example of cooperative document preparation.