ppxscal/embedding_network huggingface dataset:
An adjacency algorithm for cylindrical algebraic decompositions of three-dimenslonal space
Authors: Dennis S. Arnon, George E. Collins, Scott McCallum
Venue: Journal of Symbolic Computation (1988)

Let A @? Z [x"1, ..., x"r] be a finite set. An A-invariant cylindrical algebraic decomposition (cad) is a certain partition of r-dimenslonal euclidean space E^r into semi-algebraic cells such that the value of each A"i @? A has constant sign (positive, negative, or zero) throughout each cell. Two cells are adjacent if their union is connected. We give an algorithm that determines the adjacent pairs of cells as it constructs a cad of E^3. The general teehnlque employed for E^3 adjacency determination is ''projection'' into E^2, followed by application of an existing E^2 adjacency elgorlthm (Arnon, Collins, McCallum, 1984). Our algorithm has the following properties: (1) it requires no coordinate changes, end (2) in any cad of E^1, E^2, or E^3 that it builds, the boundary of each cell is a (disjoint) union of lower-dlmenaionel cells.
SN-2: a data acquisition and processing system
Authors: Z. Defu, Y. Peigen, S. Zhongxiu
Venue: ACM SIGPLAN Notices (1989)

SN-2 is a distributed microcomputer system designed for the testing of agricultural machines. The system is not only lower in cost but also higher in performance. A set of distributed parallel algorithms for calculating FFT etc is presented. By the algorithms the processing speed can be increased.
Low-cost networks and gateways for teaching data communications
Authors: Larry Hughes
Venue: Proceedings of the twentieth SIGCSE technical symposium on Computer science education (1989)

The growing importance of communications in computer science has resulted in many undergraduate computer science programmes offering courses in data communications. Although data communications courses can be taught in a practical manner, the cost of data communications hardware often restricts the amount of actual hands-on experience that students can gain. In this paper we describe the hardware and software requirements of several low-cost networks that can be used by students to gain experience in a wide variety of data communication topics including local area networks (such as bus networks and ring networks), wide area networks (i.e. store-and-forward networks), and gateways.
Prototyping analysis, structured analysis, Prolog and prototypes
Authors: R. A. Ribeiro, R. E. Bunker
Venue: Proceedings of the ACM SIGCPR conference on Management of information systems personnel (1988)

Techniques and tools like prototyping, high-level languages and the spreading use of PCs are changing the traditional role of a System Analyst. The application of these tools and techniques to structured systems analysis will successfully allow an analyst to build interactive working models (i.e., prototypes) for testing user requirements at an early stage of the system specification. Therefore an emerging new information system professional, here designated &ldquo;Prototyping Analyst&rdquo;, is foreseen. He/she must become an expert on the use of these new tools and techniques for improving the development of an information system in useful time. An illustrative example is developed to demonstrate how prototyping can be used to facilitate structured systems analysis.
Posture and VDU operator satisfaction
Authors: P. W. Oman, C. S. Gomes, K. Rains, M. Morandi
Venue: ACM SIGCHI Bulletin (1989)

Few studies have looked at how workers adapt their posture to fit their work environment and virtually none have compared this adaptation to reports of user satisfaction. This study focused on the relationship between users' size and posture, and the physical attributes of VDU workplaces. A survey on VDU operator satisfaction was conducted and compared to results from a controlled study on posture transitions occurring at VDU workplaces. Results demonstrate that workers adapt their posture to fit their work environment, rather than adjust their workstation to permit an optimal posture that may increase productivity. These results support the recommendations for comprehensive worker training on the ergonomic benefits of workstation adjustment and suggest the need for dynamically adjustable workstation components that periodically conform to the workers posture.
DVI parallel image compression
Authors: Michael Tinker
Venue: Communications of the ACM (1989)

At the heart of DVI is an image compression and expansion technology that uses proprietary chips to expand an image in real time from a bit stream that has been compressed on a large computer at non-real time rates. This article describes how the compression algorithm is used and how it was ported.
Recognizing and responding to plan-oriented misconceptions
Authors: Alex Quilici, Michael G. Dyer, Margot Flowers
Venue: Computational Linguistics (1988)

This paper discusses the problem of recognizing and responding to plan-oriented misconceptions in advice-seeking dialogs, concentrating on the problems of novice computer users. A cooperative response is one that not only corrects the user's mistaken belief, but also addresses the missing or mistaken user beliefs that led to it. Responding appropriately to a potentially incorrect user belief is presented as a process of 1. checking whether the advisor holds the user's belief; 2. confirming the belief as a misconception by finding an explanation for why the advisor does not hold this belief; 3. detecting the mistaken beliefs underlying the misconception by trying to explain why the user holds the incorrect belief, and 4. providing these explanations to the user. An explanation is shown to correspond to a set of advisor beliefs, and searching for an explanation to proving whether various abstract configurations of advisor beliefs hold. A taxonomy of domain-independent explanations for potential user misconceptions involving plan applicability conditions, preconditions, and effects is presented.
A hierarchical symptom classification for model based causal reasoning
Authors: C. Lee, P. Liu, S. Clark, M. Y. Chiu
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

Model based causal reasoning has been widely used for physical systems diagnosis. The system fault is localized with the causal relation of system structure and behavior. In such applications, if the system fault is not localized with the observed behavior, then a subsequent observation is made. This research studies a hierarchical symptom classification for guiding a subsequent observation in model based causal reasoning. The diagnostic symptoms are mapped to the system functional hierarchy and the symptoms are classified by partitioning the functional hierarchy. The dependency relation of symptoms guides subsequent observation. This strategy enhances the control of subsequent observation by hierarchically structuring and classifying the symptoms.
Commercial realtime software needs different configuation management
Authors: W. M. Gentleman, A. MacKay, D. A. Stewart
Venue: Proceedings of the 2nd International Workshop on Software configuration management (1989)

Arguments are presented as to why integrated, monolithic configuration management is not well suited to commercial realtime systems. An alternative approach to configuration management that over several years we have found to be effective and widely useable is described. This approach, Database and Selectors Cel (DaSC), separates treatment of versions that exist simultaneously from the evolution of those versions over time. Versions that exist simultaneously are represented by selectors from a common database. Evolution is represented by layers, as in the film animators cel.
The development of an automated flight test management system for flight test planning and monitoring
Authors: Marle Hewett, David Tartt, Eugene L. Duke, Robert F. Antoniewicz, Arvind K. Agarwal
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

This paper describes the development of an automated flight test management system (ATMS) as a component of a rapid-prototyping flight research facility for AI-based flight systems concepts. The ATMS provides a flight test engineer (FTE) with a set of tools that assist in flight test planning, monitoring and simulation. This system is also capable of controlling an aircraft during flight test by performing closed-loop guidance functions, range management, and maneuver-quality monitoring. The ATMS is being used as the prototypical system to develop a flight research facility for AI-based flight systems concepts at NASA Ames-Dryden.
Behavioral characterization of multiprocessor memory systems: a case study
Authors: K. Gallivan, D. Gannon, W. Jalby, A. Malony, H. Wijshoff
Venue: ACM SIGMETRICS Performance Evaluation Review (1989)

The speed and efficiency of the memory system is a key limiting factor in the performance of supercomputers. Consequently, one of the major concerns when developing a high-performance code, either manually or automatically, is determining and characterizing the influence of the memory system on performance in terms of algorithmic parameters. Unfortunately, the performance data available to an algorithm designer such as various benchmarks and, occasionally, manufacturer-supplied information, e.g. instruction timings and architecture component characteristics, are rarely sufficient for this task. In this paper, we discuss a systematic methodology for probing the performance characteristics of a memory system via a hierarchy of data-movement kernels. We present and analyze the results obtained by such a methodology on a cache-based multi-vector processor (Alliant FX/8). Finally, we indicate how these experimental results can be used for predicting the performance of simple Fortran codes by a combination of empirical observations, architectural models and analytical techniques.
Transforming text into hypertext for a compact disc encyclopedia
Authors: Robert J. Glushko
Venue: ACM SIGCHI Bulletin (1989)

A hypertext version of a multi-volume engineering encyclopedia on a compact disc is described. The methods for characterizing the explicit and implicit structure of the document, the novel user interface to the compact disc version, and the design and development lessons that apply to any hypertext project involving realistic amounts of text and graphics are discussed.
JANUS: integrating hypertext with a knowledge-based design environment
Authors: G. Fischer, R. McCall, A. Morch
Venue: Proceedings of the second annual ACM conference on Hypertext (1989)

Hypertext systems and other complex information stores offer little or no guidance in helping users find information useful for activities they are currently engaged in. Most users are not interested in exploring hypertext information spaces per se but rather in obtaining information to solve problems or accomplish tasks. As a step towards this we have developed the JANUS design environment. JANUS allows designers to construct artifacts in the domain of architectural design and at the same time to be informed about principles of design and the reasoning underlying them. This process integrates two design activities: construction and argumentation. Construction is supported by a knowledge-based graphical design environment and argumentation is supported by a hypertext system. Our empirical evaluations of JANUS and its predecessors has shown that integrated support for construction and argumentation is necessary for full support of design.
A kernel-independent, pipelined architecture for real-time 2-D convolution
Authors: S. B. Shukla, D. P. Agrawal
Venue: ACM SIGARCH Computer Architecture News (1988)

Existing architectures for 2-D convolution suffer from such drawbacks as inflexibility with respect to image and/or kernel sizes (systolic arrays) or data distribution and collection overhead (SIMD processor arrays). This paper introduces a pipelined architecture that maps different sizes and shapes of kernels on a fixed size array of computing elements using a single pass of the input data. It is shown that the array can be operated at its highest throughout for any kernel size. Interfacing this architecture with the host requires receiving and outputting data in a simple raster-scan fashion.
Grand challenges to computation science
Authors: Eugene Levin
Venue: Communications of the ACM (1989)

The Grand Challenges to Computational Science conference held last January attracted over 100 scientists from major universities, national laboratories, and industrial research centers. The author reports some of the highlights of the conference.
Explanation-based learning: a survey of programs and perspectives
Authors: Thomas Ellman
Venue: ACM Computing Surveys (CSUR) (1989)

Explanation-based learning (EBL) is a technique by which an intelligent system can learn by observing examples. EBL systems are characterized by the ability to create justified generalizations from single training instances. They are also distinguished by their reliance on background knowledge of the domain under study. Although EBL is usually viewed as a method for performing generalization, it can be viewed in other ways as well. In particular, EBL can be seen as a method that performs four different learning tasks: generalization, chunking, operationalization, and analogy. This paper provides a general introduction to the field of explanation-based learning. Considerable emphasis is placed on showing how EBL combines the four learning tasks mentioned above. The paper begins with a presentation of an intuitive example of the EBL technique. Subsequently EBL is placed in its historical context and the relation between EBL and other areas of machine learning is described. The major part of this paper is a survey of selected EBL programs, which have been chosen to show how EBL manifests each of the four learning tasks. Attempts to formalize the EBL technique are also briefly discussed. The paper concludes with a discussion of the limitations of EBL and the major open questions in the field.
Solving partial differential equations in a data-driven multiprocessor environment
Authors: J. L. Gaudiot, C. M. Lin, M. Hosseiniyar
Venue: ACM SIGARCH Computer Architecture News (1988)

Partial differential equations can be found in a host of engineering and scientific problems. The emergence of new parallel architectures has spurred research in the definition of parallel PDE solvers. Concurrently, highly programmable systems such as data-flow architectures have been proposed for the exploitation of large scale parallelism. The implementation of some Partial Differential Equation solvers (such as the Jacobi method) on a tagged token data-flow graph is demonstrated here. Asynchronous methods (chaotic relaxation) are studied and new scheduling approaches (the Token No-Labeling scheme) are introduced in order to support the implementation of the asynchronous methods in a data-driven environment. New high-level data-flow language program constructs are introduced in order to handle chaotic operations. Finally, the performance of the program graphs is demonstrated by a deterministic simulation of a message passing data-flow multiprocessor. An analysis of the overhead in the data-flow graphs is undertaken to demonstrate the limits of parallel operations in data-flow PDE program graphs.
Implementation of in-house developed vs application package based information systems
Authors: J. Iivari
Venue: ACM SIGMIS Database (1990)

Even though in-house development and the use of application packages form two major strategies for developing information systems, there is practically no research into the comparative implementability of information systems developed according to these strategies. The article suggests that the level or originality of information systems can be used as a theoretical concept underlying the dichotomy of in-house development vs. application packages, and puts forward a set of hypotheses regarding the influence of the level of originality on the implementability of information systems. The hypotheses form the theoretical basis for a comparison of the two types of information system development in terms of implementability, and clearly support Lynch's finding (Lynch, 1984) that the implementation of application packages is more difficult than one might initially expect.
Simulations of random divisions of an interval
Authors: C. A. O'Connor, A. Hook, A. S. Elmaghraby
Venue: ACM SIGSIM Simulation Digest (1988)

This article describes the simulation results for the following random experiment. Fix a value for the parameter p, O lt;p lt;1. Let X1 be a uniform random variable on the interval [L1, U1]=[0,1]. For n gt;2, define the random variables Xn and the random intervals [Ln, Un] by:[EQUATION]If Xn-1 lt; (Ln-1+Un-1)/2, the intervals are constructed as above with the probabilities reversed.
Supercomputer applications: helping users cope with tough programming problems
Authors: Jack Rogers
Venue: Proceedings of the 16th annual ACM SIGUCCS Conference on User Services (1988)

Nobody ever said that Supercomputing was easy. stressed-out SDSC consultant At SDSC our mission is to provide not only supercomputer cycles, but also supercomputer support. The level of support, of course, covers a broad range. Some users just need to learn the basics: how to get their data transferred to SDSC, how to get directory listings, how to access in-house application software, etc. Other users are involved in their own code installation and/or development and need to learn about the programming environment. Most of these users can cull enough information from online documentation and brief conversations with the consultants to get their codes up and running. For others, however, life is not so easy. These people are stretching the limits of computer technology, and often a great deal of time and effort is necessary simply to get their code running. Even more effort might be needed to squeeze maximum performance from the supercomputer hardware. Providing technical assistance to these people is an important part of SDSC's consulting operation. A consultant's first reaction upon encountering someone with a tough problem might be to send them away with some documentation and a wish of good luck. At SDSC, however, we feel that it is a good investment for the consultant to spend the time necessary to work with the user to solve the problem. The end result is not only a solved problem for the user, but new programming techniques that the consultant can: Teach to the original user to ease that user into the world of exotic loader options, assembly language programming, and obscure library routines. Relay to the rest of the user community by way of personal communication and newsletter articles. Use in his or her own programming projects. The following two sections trace examples of the flow of information through the consulting department at SDSC. These examples provide a glimpse into the kinds of problems SDSC users encounter and how, by solving these problems, the consulting staff can benefit not only the original user, but the user community as a whole. These examples are drawn from my own personal experience, but similar examples, of course, exist for the rest of the consulting staff.
Hyperswitch network for the hypercube computer
Authors: E. Chow, H. Madan, J. Peterson, D. Grunwald, D. Reed
Venue: ACM SIGARCH Computer Architecture News (1988)

The performance of a parallel algorithm depends in a large part on the interconnection topology of the multicomputer system. The method presented in this paper realizes a kind of interconnection network, called a hyperswitch network, that is achieved using a mixture of static and dynamic topologies. Here, available or fault free paths need not be specified by a source because the routing header can be modified in response to congestion or faults encountered as a path is established. This method can be accomplished in a static topology such as the hypercube network if the nodes have switching elements which are capable of performing the necessary routing header revisions dynamically. Detailed simulation results show that the hyperswitch network is consistently more efficient than fixed path routing for large message traffic conditions. The simulation results also show that the hyperswitch network has equivalent latency overhead for messages with localized and antilocal destinations (i.e., less then a 25% difference between diameter 1 and 5).
PAM-a noniterative approximate solution method for closed multichain queueing networks
Authors: C.-H. Hsieh, S. S. Lam
Venue: ACM SIGMETRICS Performance Evaluation Review (1988)

Approximate MVA algorithms for separable queueing networks are based upon an iterative solution of a set of modified MVA formulas. Although each iteration has a computational time requirement of O(MK2) or less, many iterations are typically needed for convergence to a solution. (M denotes the number of queues and K the number of closed chains or customer classes.) We present some faster approximate solution algorithms that are noniterative. They are suitable for the analysis and design of communication networks which may require tens to hundreds, perhaps thousands, of closed chains to model flow-controlled virtual channels. Three PAM algorithms of increasing accuracy are presented. Two of them have time and space requirements of O(MK). The third algorithm has a time requirement of O(MK2) and a space requirement of O(MK).
Performance of priorities on an 802.5 token ring
Authors: J. H. Peden, A. C. Weaver
Venue: Proceedings of the ACM workshop on Frontiers in computer communications technology (1987)

The IEEE 802.5 token ring allows the user to define multiple message priorities. The priority mechanism is implemented using a reservation scheme whereby packets attempt to reserve the token. We present an analytic model that predicts mean delay for each priority level. We show that operation of the priority mechanism is not free; that is, there is a well-defined cost (measured in terms of increased average message delay) associated with its implementation, and that in general there is minimal discrimination made between the various priority levels. We also show that the cost of the priority mechanism is an easily computable function of various network parameters. One of the circumstances where the priority mechanism results in a large discrimination between priorities is when service is limited to a single packet per received token. We show that single-packet-per-token service is necessary (but not sufficient) to gain maximum benefit from priority operation. Our main conclusion is that the network user will not, in general, receive much benefit from the priority mechanism since the priority mechanism can in fact increase slightly the delay for all priorities. The exception to this statement occurs when the network is operating under fairly extreme conditions which are well defined, and which we believe are unlikely in most installations.
A model for intelligent task scheduling in a large distributed system
Authors: Chen Jun, Xie Li, Sun Zhong-xiu
Venue: ACM SIGOPS Operating Systems Review (1990)

Most existing task scheduling algorithms will lose efficiency in a large distributed system because of the uncertainty, incompleteness, and instability problems. This paper proposes a concept of in telligent distributed task scheduling IDTS to solve these problems.