ppxscal/embedding_network huggingface dataset:
Visualization: Expanding Scientific and Engineering Research Opportunities
Authors: Thomas A. DeFanti, Maxine D. Brown, Bruce H. McCormick
Venue: Computer (1989)

The use of scientific visualization to represent the solutions obtained in computational science and engineering is discussed. The short- and long-term needs of those who use visualization tools and those who create them are addressed. For the user a three-tiered model environment is beginning to emerge that categorizes visualization systems by such factors as power, cost, and software support. Workstations with access to supercomputers are also required. The need to educate the scientific and engineering research communities about the available equipment is also discussed, and the available software and hardware are described.
Conflict resolution of rules assigning values to virtual attributes
Authors: Yannis E. Ioannidis, Timos K. Sellis
Venue: ACM SIGMOD Record (1989)

In the majority of research work done on logic programming and deductive databases, it is assumed that the set of rules defined by the user is consistent, i.e., that no contradictory facts can be inferred by the rules. In this paper, we address the problem of resolving conflicts of rules that assign values to virtual attributes. We devise a general framework for the study of the problem, and we propose an approach that subsumes all previously suggested solutions. Moreover, it suggests several additional solutions, which very often capture the semantics of the data more accurately than the known approaches. Finally, we address the issue of how to index rules so that conflicts are resolved efficiently, i.e., only one of the applicable rules is processed at query time.
On the translation of relational queries into iterative programs
Authors: Johann Christoph Freytag, Nathan Goodman
Venue: ACM Transactions on Database Systems (TODS) (1989)

This paper investigates the problem of translating set-oriented query specifications into iterative programs. The translation uses techniques of functional programming and program transformation. We present two algorithms that generate iterative programs from algebra-based query specifications. The first algorithm translates query specifications into recursive programs. Those are simplified by sets of transformation rules before the algorithm generates the final iterative form. The second algorithm uses a two-level translation that generates iterative programs faster than the first algorithm. On the first level a small set of transformation rules performs structural simplification before the functional combination on the second level yields the final iterative form.
Distributed Scheduling of Tasks with Deadlines and Resource Requirements
Authors: K. Ramamritham, J. A. Stankovic, W. Zhao
Venue: IEEE Transactions on Computers (1989)

A set of four heuristic algorithms is presented to schedule tasks that have headlines and resource requirements in a distributed system. When a task arrives at a node, the local scheduler at that node attempts to guarantee that the task will complete execution on that node before its deadline. If the attempt fails, the scheduling components on individual nodes cooperate to determine which other node in the system has sufficient resource surplus to guarantee the task. Simulation studies are performed to compare the performance of these algorithms with respect to each other as well to two baselines. The first baseline is the noncooperative algorithm where a task that cannot be guaranteed locally is not sent to any other node. The second is an (ideal) algorithm that behaves exactly like the bidding algorithm but incurs no communication overheads. The simulation studies examine how communication delay, task laxity, load differences on the nodes, and task computation times affect the performance of the algorithms. The results show that distributed scheduling is effective even in a hard real-time environment and that the relative performance of these algorithms is a function of the system state.
Automatic data/program partitioning using the single assignment principle
Authors: L. Bic, M. D. Nagel, J. M. A. Roy
Venue: Proceedings of the 1989 ACM/IEEE conference on Supercomputing (1989)

Loosely-coupled MIMD architectures do not suffer from memory contention; hence large numbers of processors may be utilized. The main problem, however, is how to partition data and programs in order to exploit the available parallelism. In this paper we show that efficient schemes for automatic data/program partitioning and synchronization may be employed if single assignment is used. Using simulations of program loops common to scientific computations (the Livermore Loops), we demonstrate that only a small fraction of data accesses are remote and thus the degradation in network performance due to multi-processing is minimal.
Constructing normalisers in finite soluble groups
Authors: S. P. Glasby
Venue: Journal of Symbolic Computation (1988)

This paper describes algorithms for constructing a Hall @p-subgroup H of a finite soluble group G and the normaliser N"G(H). If G has composition length n, then H and N"G(H) can be constructed using O(n^4 log |G|) and O(n^5 log |G|) group multiplications, respectively. These algorithms may be used to construct other important subgroups such as Carter subgroups, system normalisers and relative system normalisers. Computer implementations of these algorithms can compute a Sylow 3-subgroup of a group with n = 84, and its normaliser in 47 seconds and 30 seconds, respectively. Constructing normalisers of arbitrary subgroups of a finite soluble group can be complicated. This is shown by an example where constructing a normaliser is equivalent to constructing a discrete logarithm in a finite field. However, there are no known polynomial algorithms for constructing discrete logarithms.
On the mapping problem for multi-level systems
Authors: S. G. Ziavras
Venue: Proceedings of the 1989 ACM/IEEE conference on Supercomputing (1989)

Hierarchically-structured arrays of processors have been widely used in the low-level and the intermediate-level phases of computer vision. This is because tasks in these phases require both local and global operations, when the two-dimensional array structure of the image is considered. This paper introduces mapping (process assignment) algorithms for systems in the above class. It is the first time in parallel computer vision that both the domain and the range of the mapping functions are in a general set of hierarchically-structured arrays of processors. More specifically, the systems being studied here are not necessarily homogeneous; the processing powers of processors at different levels and the reductions between different pairs of consecutive levels are allowed to vary. Efficient mapping is achieved by first proposing objective functions, so that each objective function measures the quality of a given mapping with respect to a particular optimization goal. Mapping algorithms, one for each objective function, that attempt to produce an optimal mapping by minimizing the corresponding objective function, are then proposed. It is proven theoretically that our mapping algorithms always yield an optimal solution for systems composed of processors with identical processing powers. In all other cases, some assignment choices in the algorithms allow to take advantage of the increased processing powers of processors.
A new conceptual model for interactive user recovery and command reuse facilities
Authors: Y. Yang
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1988)

This paper generalises approaches to modelling an undo facility for interactive systems into a comprehensive user recovery and command reuse facility. It separates different undoing actions into distinct undoing functions and incorporates redoing capability in a more general command reuse capacity. Four adequacy criteria for such a facility are proposed and a general model is developed to meet these requirements. Partial, patterned and repetitive undoing and redoing actions are allowed on simple, complex and meta commands. The model subsumes the functionality of prior models.
Retargeting an Ada source level debugger to CICS
Authors: G. Snyder, D. Dunkle, K. Beitz
Venue: Proceedings of the conference on Tri-Ada '89: Ada technology in context: application, development, and deployment (1989)

Several characteristics of CICS make design of an Ada source level debugger difficult. This paper describes these difficulties, and solutions used in retargeting AdaView&trade;, (a full featured Ada source level debugger, written in Ada), so that it can debug Ada application programs running under CICS. Special consideration is given to debugging pseudoconversational applications, the most common type of CICS interactive application. AdaView's main part, running under MVS, communicates with a small CICS resident part via SNA LU 6.2 APPC protocol.
Test generation of stuck-open faults using stuck-at test sets in CMOS combinational circuits
Authors: H. K. Lee, D. S. Ha, K. Kim
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

In this paper we investigate two aspects regarding the detection of stuck-open (SOP) faults using stuck-at test sets. First, we measure the SOP fault coverage of stuck-at test sets for various CMOS combinational circuits. The SOP fault coverage is compared with that of random pattern test sets. Second, we propose a method to improve the SOP fault coverage of stuck-at test sets by organizing the test sequence of stuck-at test sets. The performance of the proposed method is compared with that of a competing method. Experimental results show that the proposed method leads to smaller test sets and shorter processing time while achieving high SOP fault coverage.
Probabilistic inductive inference
Authors: L. Pitt
Venue: Journal of the ACM (JACM) (1989)

Inductive inference machines construct programs for total recursive functions given only example values of the functions. Probabilistic inductive inference machines are defined, and for various criteria of successful inference, it is asked whether a probabilistic inductive inference machine can infer larger classes of functions if the inference criterion is relaxed to allow inference with probability at least p, (0 < p < 1) as opposed to requiring certainty. For the most basic criteria of success (EX and BC), it is shown that any class of functions that can be inferred from examples with probability exceeding 1/2 can be inferred deterministically, and that for probabilities p &le; 1/2 there is a discrete hierarchy of inferability parameterized by p. The power of probabilistic inference strategies is characterized by equating the classes of probabilistically inferable functions with those classes that can be inferred by teams of inductive inference machines (a parallel model of inference), or by a third model called frequency inference.
Extensions of Scale-Space Filtering to Machine-Sensing Systems
Authors: B. Zuerndorfer, G. H. Wakefield
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

Major components of scale-space theory are Gaussian filtering, and the use of zero-crossing thresholders and Laplacian operators. Properties of scale-space filtering may be useful for data analysis in multiresolution machine-sensing systems. However, these systems typically violate the Gaussian filter assumption, and often the data analyses used (e.g. trend analysis and classification) are not consistent with zero-crossing thresholders and Laplacian operators. The authors extend the results of scale-space theory to include these more general conditions. In particular, it is shown that relaxing the requirement of linear scaling allows filters to have non-Gaussian spatial characteristics, and that relaxing of the scale requirements (s to 0) of the impulse response allows the use of scale-space filters with limited frequency support (i.e. bandlimited filters). Bandlimited scale-space filters represent an important extension of scale-space analysis for machine sensing.
Implementing the recursive APL code for dynamic programming
Authors: Edward Y. H. Lin, Dennis L. Bricker
Venue: ACM SIGAPL APL Quote Quad (1990)

Despite the importance and wide applicability of dynamic programming technique in optimization, the complexity and uniqueness of various dynamic programming models often make the comprehension of their solution procedures difficult, particularly for a novice. Although it can be argued that, unlike the Simplex method in linear programming, no general dynamic programming algorithm exists, with the recursive capability of APL, it is feasible to develop a &ldquo;systematic&rdquo; solution approach for deterministic dynamic programming. In this paper, we introduce a set of such APL code developed be solve various types of dynamic programming problems with minor modifications on some of its key functions to accommodate the nature of each type of dynamic programming problems.
Coloring heuristics for register allocation
Authors: P. Briggs, K. D. Cooper, K. Kennedy, L. Torczon
Venue: ACM SIGPLAN Notices (1989)

We describe an improvement to a heuristic introduced by Chaitin for use in graph coloring register allocation. Our modified heuristic produces better colorings, with less spill code. It has similar compile-time and implementation requirements. We present experimental data to compare the two methods.
The network control assistant (NCA), a real-time prototype expert system for network management
Authors: Perry M. Kosieniak, Victor Mathis, Michael St. Jacques, Delano Stevens
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

Prototype network management software supported by a real-time expert system to monitor and control the public telephone voice network is described. This system, called the Network Control Assistant (NCA), was mostly written in Prolog on an IBM PC/AT. The human interface for NCA consists of an efficiently designed hierarchy of color enhanced screens with user selected options. The responsive advisory system contains about 60 customized rules with features intended to enhance real-time performance. Other support software in NCA captures and parses telephone switch traffic reports in real-time using a natural language technique. Parsing was necessary because no direct data-acquisition interface was available on the target switches (GTE's No. 2 EAX and GTD-5) and verbose status reports designed to be read at a terminal by humans were intercepted as a source of data. Implementation issues and unique features for real-time use of NCA are addressed and pertinent conclusions are summarized.
3D scene on 2D screen: the VISUALCAD connection
Authors: N. Kodali
Venue: ACM SIGCHI Bulletin (1989)

Working with 3D space through the 2D computer screen is a skill that has to be mastered by CAD users. Current user interface designs fail to address the basic issue of relating the users' mental space with the computer's construction space. VISUALCAD, a new technique developed to communicate 3D CAD concepts, combines the users' mental space and the computers construction space. Through the use of video tools it enables us to discuss and demonstrate the key concepts in CAD all in one real space. The use of video is found to be an indispensable part of CAD training.
Binsorting on hypercubes with d-port communication
Authors: S. R. Seidel, W. L. George
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications - Volume 2 (1989)

Three sorting algorithms are given for hypercubes with d-port communication. All of these algorithms are based on binsort at the global level. The binsort allows the movement of keys among nodes to be performed by a d-port complete exchange rather than a sequence of l-port exchanges as in other algorithms. This lowers communication costs by at least a factor of d compared to other sorting algorithms. The first algorithm assumes the keys are uniformly distributed and selects bin boundaries based on the global maximum and minimum keys. The other two algorithms make no assumption about the distribution of keys and so they sample the keys before the binsort in order to estimate their distribution. Splitting keys based on that estimate reduce the variance among the lengths of the subsequences left in the nodes after the complete exchange of bins which in turn helps to balance the computational load in each node. The performance of two of these algorithms on an FPS T-40 is given for data of various distributions and is compared to the performance of bitonic sort and hyperquicksort.
Synchronous Optical Network and Broadband ISDN Protocols
Authors: Anna Hac, Hasan B. Mutlu
Venue: Computer (1989)

High-level technical information on Sonet (synchronous optical network) B-ISDN (broadband integrated services digital network) protocols, and interface structures is provided. Since the B-ISDN protocol standards to be used in the Broadband Reference Model are currently being discussed in the CCITT, most of the standards are not yet available. Therefore, some of the protocols described here are not based on agreements reached in national and international standards bodies. The discussion covers B-ISDN architecture and the ISO model. Sonet protocols and architecture, B-ISDN configuration, and the ATM (asynchronous transfer model) architecture.
Patterns of contact and communication in scientific research collaboration
Authors: Robert Kraut, Carmen Egido, Jolene Galegher
Venue: Proceedings of the 1988 ACM conference on Computer-supported cooperative work (1988)

In this paper, we describe the influence of physical proximity on the development of collaborative relationships between scientific researchers and on the execution of their work. Our evidence is drawn from our own studies of scientific collaborators, as well as from observations of research and development activities collected by other investigators. These descriptions provide the foundation for a discussion of the actual and potential role of communications technology in professional work, especially for collaborations carried out at a distance.
Design and performance of a coherent cache for parallel logic programming architectures
Authors: A. Goto, A. Matsumoto, E. Tick
Venue: ACM SIGARCH Computer Architecture News (1989)

This paper describes the design and performance of a tightly-coupled shared-memory coherent cache optimized for the execution of parallel logic programming architectures. The cache utilizes a copy-back write-allocation protocol having five states and a hardware lock mechanism. Optimizations for logic programming are introduced in four software-controlled memory access commands: direct-write, exclusive-read, read-purge, and read-invalidate. In this paper we describe these operations and present simulated measurements showing their performance advantage for an architecture of the committed-choice language KL1. The cache optimizations also improve the performance of non-committed-choice languages, such as OR-parallel Prolog. A version of the cache design described here is currently being implemented for ICOT's Parallel Inference Machine (PIM).
SUI: a system independent user interface for an integrated scientific computing environment
Authors: Y. Doleh, P. S. Wang
Venue: Proceedings of the international symposium on Symbolic and algebraic computation (1990)

The design and implementation of a Scientific User Interface is presented. Written in the C language, SUI is a window-menu-mouse oriented graphical user interface that is designed to provide a modern and integrated computing environment for scientific work. SUI can serve multiple client systems in parallel including symbolic, numeric, graphics and document formatting systems. SUI achieves hardware and operating system independence as well as network transparency by employing the X11 protocols and achieves client system independence by defining a client-SUI protocol that is simple and effective. Features of SUI includes input editing, history, 2-D mathematical expression display, interactive selection of subexpressions, interactive display and manipulation of 2-D and 3-D plots of mathematical functions, cut and paste with syntax translation, command templates, incremental 2-D display of mathematical input, and interactive configuration. A prototype system demonstration is planned for ISSAC'90
A two-dimensional view controller
Authors: Andrew S. Glassner
Venue: ACM Transactions on Graphics (TOG) (1990)

Description: Many two-dimensional graphics programs provide a user with a rectangular screen window for viewing a two-dimensional image. Common examples of this underlying &ldquo;world&rdquo; image include text, line, or shaded pictures, and plots of one- or two-dimensional functions. Typically the screen image cannot display the world image with a 1:1 ratio between screen units (pixels) and the smallest resolvable world units. Thus the screen image is typically scaled and panned across the world image. The scaling is often differential, i.e., different scaling factors are applied in X and Y. Suppose a user is viewing a function y = f(x) at a ratio of 1:1. Increasing the scale factor in X will bring more data into view, while retaining vertical amplitude; increasing the scale factor in Y will provide a finer view of the values of the function, while retaining the range plotted. We have developed a compact control device which allows a user to continuously adjust the aspect ratio of the world data presented to the window. Our model is based on the projection of the window on the untouched world data. If the screen window is narrow and tall in the world data, then the world data will be expanded horizontally and compressed vertically when displayed on the screen (note that the window itself never changes size on the screen). Accompanying the aspect ratio selection is a zoom multiplier, which can uniformly grow or shrink the screen window's image in the world. We also include variable-speed scrolling controls. Scrolling and uniform zooming are decoupled from differential scaling. The advantage of our technique is that the user need not independently scale X and Y while searching for the proper scaling of data; although both may be adjusted individually, and may also be adjusted simultaneously in a coupled, single-position device. Thus a single-button input device (such as a mouse) is all that is needed to control any aspect of the display. The technique has the additional advantage of being nonmodal, so the user need not remember any state during operation.
Space-Efficient and Fault-Tolerant Message Routing in Outerplanar Networks
Authors: G. N. Frederickson, R. Janardan
Venue: IEEE Transactions on Computers (1988)

The problem of designing space- and communication-efficient routing schemes for networks that experience faults is addressed. For any outerplanar network containing t faults, a succinct routing scheme is presented that uses O( alpha tn) space and communication to generate routings that are less than (( alpha +1)/( alpha -1))/sup t/ times longer than optimal, where alpha
Parcel: project for the automatic restructuring and concurrent evaluation of LISP
Authors: L. Harrison
Venue: Proceedings of the 2nd international conference on Supercomputing (1988)

Parcel (Project for the Automatic Restructuring and Concurrent Evaluation of Lisp) is an investigation of the problem of compiling Lisp for evaluation on a shared memory multiprocessor. In this paper, we present an overview of the process of compilation in Parcel. This process consists, broadly, of an interprocedural analysis, followed by a function-level restructuring of the lambda expressions that constitute a program. We discuss both of these phases, and illustrate the steps of restructuring with a few examples. A novel representation for s-expressions is employed in Parcel, to facilitate the parallel creation and access of lists; we review this representation, and discuss its implications for the compilation process. We conclude with some preliminary performance measurements of the prototypes of the Parcel compiler and run-time system.