ppxscal/embedding_network huggingface dataset:
Static type inference for parametric classes
Authors: A. Ohori, P. Buneman
Venue: Conference proceedings on Object-oriented programming systems, languages and applications (1989)

Central features of object-oriented programming are method inheritance and data abstraction attained through hierarchical organization of classes. Recent studies show that method inheritance can be nicely supported by ML style type inference when extended to labeled records. This is based on the fact that a function that selects a field &fnof; of a record can be given a polymorphic type that enables it to be applied to any record which contains a field &fnof;. Several type systems also provide data abstraction through abstract type declarations. However, these two features have not yet been properly integrated in a statically checked polymorphic type system. This paper proposes a static type system that achieves this integration in an ML-like polymorphic language by adding a class construct that allows the programmer to build a hierarchy of classes connected by multiple inheritance declarations. Moreover, classes can be parameterized by types allowing &ldquo;generic&rdquo; definitions. The type correctness of class declarations is statically checked by the type system. The type system also infers a principal scheme for any type correct program containing methods and objects defined in classes.
Criteria for Selecting a Variable in the Construction of Efficient Decision Trees
Authors: Masahiro Miyakawa
Venue: IEEE Transactions on Computers (1989)

Two variable selection criteria are proposed for converting a decision table to a near-optimum decision tree in the sense of minimal average cost of testing. A criterion, Q, is introduced that is based on the potential of a decision table. The previously known criterion 'loss' and Q are combined into a third criterion O. The performance of the three criteria is examined both theoretically and experimentally. Of most importance is that Q and O do not select a nonessential variable, while 'loss' may do so. It is also shown that the performance of the three criteria is not worse than that of any other known heuristics, at least for a particular example. The algorithm requires at most O(L/sup 2/2/sup L/) operations, where L is the arity of an input table.
Coping with Discontinuities in Computer Vision: Their Detection, Classification, and Measurement
Authors: D. Lee
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

The general principles of detection, classification, and measurement of discontinuities are studied. The following issues are discussed: detecting the location of discontinuities; classifying discontinuities by their degrees; measuring the size of discontinuities; and coping with the random noise and designing optimal discontinuity detectors. An algorithm is proposed for discontinuity detection from an input signal S. For degree k discontinuity detection and measurement, a detector (P, Phi ) is used, where P is the pattern and Phi is the corresponding filter. If there is a degree k discontinuity at location t/sub 0/, then in the filter response there is a scaled pattern alpha P at t/sub 0/, where alpha is the size of the discontinuity. This reduces the problem to searching for the scaled pattern in the filter response. A statistical method is proposed for the approximate pattern matching. To cope with the random noise, a study is made of optimal detectors, which minimize the effects of noise.
Dense representation of affine coordinate rings of curves with one point at infinity
Authors: S. C. Porter
Venue: Proceedings of the ACM-SIGSAM 1989 international symposium on Symbolic and algebraic computation (1989)

Traditional methods of representing rational functions on curves are unwieldy and unsuitable for solution of many problems. This paper describes a simple and elegant representation of elements of the affine coordinate ring of an algebraic curve and describes efficient, easy to implement algorithms to perform addition, subtraction, multiplication and polynomial evaluation. This data structure overcomes many of the disadvantages of more unwieldy traditional representations. Elements are represented as vectors of elements of the ground field in a manner similar to the representation of polynomials of one variable as an array of coefficients. This data structure is a fundamental ingredient in the author's decoding method for algebraic geometry codes. The rational function approximation techniques used for decoding could not have been described with multivariate polynomials or truncated infinite series.
Software CAD: A Revolutionary Approach
Authors: Raymond J. A. Buhr, Gerald M. Karam, Carol J. Hayes, C. Murray Woodside
Venue: IEEE Transactions on Software Engineering (1989)

A research project is described in which an experimental software CAD environment called the Carleton embedded system design environment (CAEDE), oriented toward embedded systems and Ada, was developed to provide a demonstration of the concept and to serve as a research testbed. The major contribution of CAEDE is a demonstration of a visual paradigm which combines semantic depth and syntactic shallowness, relative to Ada, in a manner that makes it possible for the embedded-system designer to work in terms of abstract machines while still thinking Ada. A secondary contribution is the identification of Prolog as a promising approach for supporting tool development in an environment which supports the visual paradigm. Also described are experimental tools for temporal analysis, performance analysis, and the generation of skeleton Ada code.
Modeling for text compression
Authors: Timothy Bell, Ian H. Witten, John G. Cleary
Venue: ACM Computing Surveys (CSUR) (1989)

The best schemes for text compression use large models to help them predict which characters will come next. The actual next characters are coded with respect to the prediction, resulting in compression of information. Models are best formed adaptively, based on the text seen so far. This paper surveys successful strategies for adaptive modeling that are suitable for use in practical text compression systems. The strategies fall into three main classes: finite-context modeling, in which the last few characters are used to condition the probability distribution for the next one; finite-state modeling, in which the distribution is conditioned by the current state (and which subsumes finite-context modeling as an important special case); and dictionary modeling, in which strings of characters are replaced by pointers into an evolving dictionary. A comparison of different methods on the same sample texts is included, along with an analysis of future research directions.
Location of a Faulty Module in a Computing System
Authors: Tein-Hsiang Lin, Kang G. Shin
Venue: IEEE Transactions on Computers (1990)

Considering the interplay between different phases of fault tolerance, a new problem of locating a faulty module in a computing system is formulated and solved. First, the probability of each module being faulty, or faulty probability, is calculated using the likelihood principle from the model parameters for fault detection, diagnostics, error propagation, and error detection. Then, based on the faulty probabilities and a given required diagnostic coverage, the order in which modules are to be diagnosed and the maximum time allotted to diagnose each module are determined by minimizing the average total diagnostic time. An example is presented and analyzed to answer the question of whether or not a system should delay the diagnosis upon detection of an error until more errors are detected.
An IS1 workbench for ACM information system curriculum '81
Authors: Leslie J. Waguespack,  Jr.
Venue: ACM SIGCSE Bulletin (1989)

This paper describes the System Architects' Workbench, a personal computer-based teaching environment for courses in computer organization and systems programming. This tool set provides an integrated learning and teaching environment for computer systems concepts defined in ACM IS Curriculum '81 IS1. The central tool is a computer simulator based on a pedagogical model of computer system resources which allows students to study principles without becoming too involved in the implementation idiosyncrasies usually associated with machine level programming. Programs may be written directly in machine language or in a Pascal-like language, TP, which includes features that allow complete access to and control of host level resources. The TP compiler supports separate compilation, IPL load module generation, and detailed translation output used for machine language modification and debugging. The simulator supports interactive execution, tracing, modification, and debugging.
Understanding selective assignment
Authors: J. A. Brown, B. Hawks
Venue: Conference proceedings on APL as a tool of thought (1989)

This paper discuses the rules for evaluating expressions on the left of an assignment arrow and shows that ordinary assignment and vector assignment are just special cases of selective assignment. This unification of the three kinds of assignment expressions represents consistent and proper extensions that could be added to any future APL 2 implementations.
Motivations and behaviors of software professionals
Authors: H. I. Rubin, E. F. Hernandez
Venue: Proceedings of the ACM SIGCPR conference on Management of information systems personnel (1988)

This paper reports on a study exploring the motivations of professional software workers. We hypothesized that extrinsic motivation is more important to software professionals of today than to those of fifteen to twenty years ago, and that among those in the field today, it is most important for those who had been in the profession for the shortest time. Conversely, we hypothesized that intrinsic motivation is less important to software professionals of today than to those of fifteen to twenty years ago, and that among those in the field today, it is least important for those who had been in the profession for the shortest time. We also expected to find that hours of recreational computer use would be positively correlated with intrinsic motivation and negatively correlated with extrinsic motivation. A review of the literature uncovered a number of studies of DP/MIS personnel which showed that they have high growth needs. This indicates that DP/MIS personnel are concerned with intrinsic factors. We found no longitudinal surveys studying the motivation of computer professionals. Analysis of data from studies in 1969-70 and 1972-73 [26, 27] suggested that at the times of these studies intrinsic motivations were more important to software professionals than to the general workforce, and extrinsic motivations less important. However, the numbers of respondents in these studies who were software professionals were so small (three and eight, respectively) that the results are not statistically valid. We designed and carried out a Survey of Software Professionals (&ldquo;SSP&rdquo;), obtaining responses from local businesses and through the Usenet worldwide computer network. After analyzing data from the SSP and from the earlier studies we have concluded (1) that the longer a person has been in the software field the less important extrinsic motivations are to them; (2) that intrinsic motivation has not changed over time, nor does it change the longer one remains in the profession; and (3) software professionals who engage in recreational computer use have higher intrinsic motivation than those who do not.
Flight mission scenario generation with knowledge-based system
Authors: Sowmyan Raman
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

ScenGen (FLIGHT MISSION ScenARIO GenERATOR) is a prototype knowledge based system being developed at Boeing for the Flight Crew Operations Requirements Group. The main objective of ScenGen is to provide a system which utilizes the tools and problem solving heuristics employed by the Flight Deck Engineers in developing Flight Mission Scenarios. A Flight Mission Scenario describes the flight crew activity associated with flying a route. The set of flight procedures to be accomplished and the time available for performance are dictated by the Flight Scenario. The creation of a scenario is based upon data derived from mission flight plans, flight maps, approach and landing charts, Air Traffic Control (ATC) operational data, airplane performance data, and airplane operations manuals. Using this knowledge, detailed procedures are developed to successfully complete a mission. These procedures establish the basic work units from which all work load statistics are derived. As a part of the Federal Aviation Authority (FAA) certification process, it is necessary to establish the minimum crew required for safe operation of an airplane. Crew size certification involves a complete flight deck design evaluation. The evaluation includes analytical workload analysis of each individual crew member Development of flight mission scenario is the first step in the analytical workload analysis of the crew. This paper describes why and how ScenGen was developed, the problems encountered, and its current status as well as future directions.
ODE (Object Database and Environment): the language and the data model
Authors: R. Agrawal, N. H. Gehani
Venue: ACM SIGMOD Record (1989)

ODE is a database system and environment based on the object paradigm. It offers one integrated data model for both database and general purpose manipulation. The database is defined, queried and manipulated in the database programming language O++ which is based on C++. O++ borrows and extends the object definition facility of C++, called the class. Classes support data encapsulation and multiple inheritance. We provide facilities for creating persistent and versioned objects, defining sets, and iterating over sets and clusters of persistent objects. We also provide facilities to associate constraints and triggers with objects. This paper presents the linguistic facilities provided in O++ and the data model it supports.
Defining faster transfer syntaxes for the OSI presentation protocol
Authors: C. Huitema, A. Doghri
Venue: ACM SIGCOMM Computer Communication Review (1989)

In an heterogeneous environment, applications must agree the structure and a binary representation of the exchanged data. This can a priori be done by adopting by the two standards proposed by ISO: the Abstract Syntax Notation 1 (ASN-1) and the ASN-1 basic encoding rules (ASN1-BER). However, the ASN1-BER conversion procedures are highly CPU consuming, which is not acceptable for several "high speed" applications. We propose to use the presentation layer negotiation to select faster transfer syntax. We have experimented with a first "light weight" syntax since 1988, and have just completed the definition a new "flat tree light weight syntax", which can be orders of magnitude faster than the ASN1-BER.
Polycyclic Vector scheduling vs. Chaining on 1-Port Vector supercomputers
Authors: J. H. Tang, E. S. Davidson, J. Tong
Venue: Proceedings of the 1988 ACM/IEEE conference on Supercomputing (1988)

This paper studies the impact of chaining and several instruction scheduling schemes on one-memory-port vector supercomputers, illustrated by the Cray-1 and Cray-2. The lack of instruction chaining in the Cray-2 vector processor requires a different instruction scheduling scheme from that of the Cray-1. Situations are characterized in which simple vector scheduling can generate optimal code, which fully utilizes at least one functional unit for machines with chaining. With enough registers polycyclic scheduling, even without chaining, guarantees full utilization of one functional unit, after an initial transient, for loops with acyclic dependence graphs. Workloads are represented by vectorizable Livermore Fortran Kernels (LFKs). The effectiveness of applying polycyclic scheduling to the Cray-2 is compared with optimal simple vector scheduling on the Cray-1. The speedup of polycyclic vector scheduling on the Cray-2 over the schedule achieved by the current CFT77 compiler on several vectorizable LFKs is also presented.
Knowledge acquisition at the metalevel: creation of custom-tailored knowledge-acquisition tools
Authors: Mark A. Musen
Venue: Issue 108 (April 1989) (1989)

Automated knowledge-acquisition tools can assist system builders in the creation of knowledge bases for expert systems. An important class of such tools includes programs that contain detailed models of families of application tasks. Users enter knowledge about particular applications into these tools in terms of the predefined task models that the tools incorporate. Construction of such tools, however, has itself proven to be laborious. PROT Eacute;G Eacute; is an interactive program that assists knowledge engineers in the construction of task models, and that automatically generates custom-tailored, graphical knowledge-acquisition tools based on those models. Domain experts independently use the knowledge-acquisition tools that PROT Eacute;G Eacute; generates to enter the knowledge that defines individual applications. The methodology simplifies the development of task-based knowledge-acquisition aids, and allows system builders to separate the difficult, model-building part of knowledge acquisition from the more straightforward entry of content knowledge.
New Results in Fuzzy Clustering Based on the Concept of Indistinguishability Relation
Authors: R. Lopez de Mantaras, L. Valverde
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1988)

The issue of validity in clustering is considered and a definition of fuzzy r-cluster that extends E. Ruspini's definition (1982) is proposed. This definition is based on an indistinguishability relation based on the concept of t-norm. The fuzzy r-cluster's metrical properties are studied through the dual concept of t-conorm that leads to G-pseudometrics. From the concept of G-pseudometric, fuzzy r-clusters and fuzzy cluster coverages are defined. The authors propose a measure of cluster validity based on the concept of fuzzy coverage. The basic idea of the approach presented is that the smaller the difference between the degrees of membership and the degrees of indistinguishability, the better the clustering.
Dynamic Testing Strategy for Distributed Systems
Authors: F. J. Meyer, D. K. Pradhan
Venue: IEEE Transactions on Computers (1989)

Fault diagnosis is treated as two distinct processes: fault discovery and dissemination of diagnostic information. Previous research determined what level of self-diagnosability a given set of test in a homogeneous system achieves, using a model in which only node failures occur and test coverage is complete. Adopting the same model, a new methodology is presented that minimizes the overhead associated with periodic testing, thus lowering testing overhead. The method diagnoses up to c-.1 faults (c is the connectivity of the system topology). The savings in testing is valid when processor failure rates are low. Environments are also examined with high processor failure rates. It is shown that adopting the proposed methodology for such systems results in greater reliability, while maintaining the same effective processing power.
Ada tasking and parallel processors
Authors: M. Linnig, D. Forinash
Venue: Proceedings of the conference on Tri-Ada '89: Ada technology in context: application, development, and deployment (1989)

This paper describes the creation of a shared memory multiprocessor runtime that uses the Ada language tasking model as the basis for CPU allocation. The modifications to an Ada runtime targeted to a single MIL-STD-1750A processor to create a multiprocessor Ada runtime are described. Some performance information is given.
Performance study of a clustered shared-memory multiprocessor
Authors: K. B. Irani, A. R. Naji
Venue: Proceedings of the 2nd international conference on Supercomputing (1988)

A shared-memory multiprocessor having clusters of processing elements and memory modules is considered. Each cluster has two others as its neighbors. The clusters are interconnected in such a way that the memory modules of a cluster can also be accessed by the processors of the neighboring clusters besides its own processors through its cluster interconnection network. The processors and memories of all clusters are also connected to a shared interconnection network. This permits processors to access memory modules of the non-neighboring clusters. Generalized multistage interconnection networks are used for both types of connections. The time required to access memory modules is reduced by scheduling tasks sharing large data with each other on neighboring clusters or on the same cluster thereby providing for memory access a low latency path through the cluster interconnection network. The time to access memory modules of the non-neighboring clusters also reduces due to reduced contention and because of fewer requests going through the shared interconnection network. Since the memory modules of a cluster are the main memory modules, an additional level of cluster memory is not required. This alleviates the data coherence problem. A Markov chain model is used to study the performance of this multiprocessor under circuit switching. Considerable improvement in performance over a simple shared memory multiprocessor using multistage interconnection network is observed. The model is extended to study the effects of synchronized memory access to shared data.
Particle animation and rendering using data parallel computation
Authors: Karl Sims
Venue: Proceedings of the 17th annual conference on Computer graphics and interactive techniques (1990)

Techniques are presented that are used to animate and render particle systems with the Connection Machine CM-2, a data parallel supercomputer. A particle behavior language provides an animator with levels of control from kinematic spline motions to physically based simulations. A parallel particle rendering system allows particles of different shapes, sizes, colors and transparencies to be rendered with antialiasing, hidden surfaces, and motion-blur. One virtual processor is assigned to each primitive data element: one to each particle, and during the rendering process, one to each pixel-sized particle fragment, and to each pixel. These tools are used to model dynamic phenomena such as wind, snow, water, and fire.
Accurate modeling of parallel scientific computations
Authors: D. M. Nicol, J. C. Townsend
Venue: ACM SIGMETRICS Performance Evaluation Review (1989)

Scientific codes are usually parallelized by partitioning a grid among processors. To achieve top performance it is necessary to partition the grid so as to balance workload and minimize communication/synchronization costs. This problem is particularly acute when the grid is irregular, changes over the course of the computation, and is not known until load-time. Critical mapping and remapping decisions rest on our ability to accurately predict performance, given a description of a grid and its partition. This paper discusses one approach to this problem, and illustrates its use on a one-dimensional fluids code. The models we construct are shown empirically to be accurate, and are used to find optimal remapping schedules.