ppxscal/embedding_network huggingface dataset:
Grasping reality through illusion&mdash;interactive graphics serving science
Authors: F. P. Brooks
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1988)

I treat three related subjects: virtual-worlds research&mdash;the construction of real-time 3-D illusions by computer graphics; some observations about interfaces to virtual worlds; and the coming application of virtual-worlds techniques to the enhancement of scientific computing. We need to design generalized interfaces for visualizing, exploring, and steering scientific computations. Our interfaces must be direct-manipulation, not command-string; interactive, not batch; 3-D, not 2-D; multisensory, not just visual. We need generalized research results for 3-D interactive interfaces. More is known than gets reported, because of a reluctance to share &ldquo;unproven&rdquo; results. I propose a shells-of-certainty model for such knowledge.
Broadcast Normalization in Systolic Design
Authors: F.-C. Lin, I.-C. Wu
Venue: IEEE Transactions on Computers (1988)

When a sequential algorithm is directly mapped into an array of processing elements, quite likely data broadcasts are required and their source places vary during the computation. The authors introduce a normalization method to fix the positions of the broadcast sources so that the derived design can be further transformed by retimings into a systolic array. The method is fully illustrated in designing systolic arrays for enumeration sort, solving simultaneous linear equations, and transitive closure.
A unified data exchnage environment based on EDIF
Authors: W. Li, H. Switzer
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

This paper describes the work to unify a data exchange environment based on EDIF. Concepts of common specification, common data structure, and common EDIF reader/writer to synchronize the interpretations of EDIF syntax and semantics in an EDIF-based data exchange environment are introduced. An EDIF-compatible database which improves the speed of the data manipulation and generates portable, standard EDIF is also described.
Behavioral evaluation and analysis of a hypertext browser
Authors: Dennis E. Egan, Joel R. Remde, Thomas K. Landauer, Carol C. Lochbaum, L. M. Gomez
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: Wings for the mind (1989)

Students performed a variety of tasks using a statistics text presented either in conventional printed form or via the text browser &ldquo;SuperBook&rdquo; (Remde, Gomez and Landauer [18]). Students using SuperBook answered more search questions correctly, wrote higher quality &ldquo;open-book&rdquo; essays, and recalled certain incidental information better than students using the conventional text. Subjective ratings overwhelmingly favored SuperBook. The advantage of SuperBook appears to be particularly strong for questions that are not anticipated by the author's organization of a text.
DOAS: an object oriented architecture supporting secure languages
Authors: A. J. van de Goor, H. Corporaal
Venue: Proceedings of the 22nd annual workshop on Microprogramming and microarchitecture (1989)

Current software engineering practice heavily relies on the reliability of software implementation languages and underlying architectures. However, both the currently used languages, as well as the traditional architectures suffer from a shortage of built-in security. In this paper, an architecture is presented, which is heavily influenced by two properties of secure languages: coercion and exception handling. It is shown that proper design decisions lead to an architecture having a compact data representation, allowing both generic and nongeneric instructions. The architecture is object oriented, and object addressing is under control of the operand stream, with optimalisation possibilities to bypass descriptor inspection.
Hardware Algorithms for Determining Similarity Between two Strings
Authors: A. Mukherjee
Venue: IEEE Transactions on Computers (1989)

The author presents pipelined hardware algorithms with time complexity O(n+m) for determining between two character strings expressed as the length of the longest common subsequence of the given pair of strings. The algorithms use cellular architecture with simple basic cells and regular nearest-neighbor communication generally suitable for VLSI implementation. Two methods are presented: a sequential method with serial text input and an alternating method in which both the pattern and the text are serially applied to the machine. Theorems are proved that lead to a very optimized design of a basic cell.
Computing dimension and independent sets for polynomial ideals
Authors: Heinz Kredel, Volker Weispfenning
Venue: Journal of Symbolic Computation (1988)

We present an algorithm that computes the dimension and maximal independent sets for a polynomial ideal I from a Grobner basis for I with respect to a lexicographical term order, and extends Buchberger's test for zero-dimensionality. The algorithm is (for a given lexicographical Grobner basis) faster, than the method of Moller & Mora (1983) using the computation of the Hilbert polynomial, and yields important additional information on independent sets and associated prime ideals. Its verification involves the new concept of strong independence modulo an ideal with respect to an admissible term order. The algorithm is implemented in the ALDES/SAC-2 system of Collins & Loos (1980), and has been tested successfully on the examples from Boge et al. (1986) and other examples.
ARTS: a distributed real-time kernel
Authors: H. Tokuda, C. W. Mercer
Venue: ACM SIGOPS Operating Systems Review (1989)

ARTS is a distributed real-time operating system designed for a real-time systems testbed being developed at Camegle Mellon University. The objective of the testbed is to develop and verify advanced real-time computing technologies for a distributed environment. The tastbed consists of a set of SUN3 workstations connected by a real-time network based on IEEE 802.5 Token Ring and Ethernet. The goal of the ARTS Kernel is not to produce simply a fast real-time executive, but rather to provide users with a predictable, analyzable, and reliable distributed real-time computing environment. In particular, we have developed a real-time object model which is incorporated with a time fence protocol. The time fence protocol is used at every invocation in the object to detect the origin of timing errors. We also developed an integrated time-driven scheduling model and its scheduler based on the notion of policy/mechanism separation. Since each scheduling policy is implemented as a kernel object, a user can easily add policies or change the system's scheduling policy. A real-time toolset was also developed in order to predict the schedulability of the real-time activities.In this paper, we give an overview of the ARTS Kernel and ARTS real-time toolset. In particular, we introduce a real-time object model and the integrated time-driven scheduling model. We then describe the basic primitives and major components of the ARTS Kernel and the real-time toolset which consists of the schedulability analyzer, Scheduler 1-2-3, and the real-time monitor/debugger, ARM.
Parallel reductions in ¿-calculus
Authors: Masako Takahashi
Venue: Journal of Symbolic Computation (1989)

The notion of parallel reduction is extracted from the Tait-Martin-Lof proof of the Church-Rosser theorem (for @b-reduction). We define parallel @b-, @h- and @b@h-reduction by induction, and use them to give simple proofs of some fundamental theorems in @l-calculus; the normal reduction theorem for @b-reduction, that for @b@h-reduction, the postponement theorem of @h-reduction (in @b@h-reduction), and some others.
A framework for understanding the workspace activity of design teams
Authors: John C. Tang, Larry J. Leifer
Venue: Proceedings of the 1988 ACM conference on Computer-supported cooperative work (1988)

Small group design sessions were empirically studied to understand better collaborative workspace activity. A conventional view of workspace activity may be characterized as concerned only with storing information and conveying ideas through text and graphics. Empirical evidence shows that this view is deficient in not accounting for how the workspace is used: a) in a group setting, rather than by an individual, and b) as part of a process of constructing artifacts, rather than just a medium for the resulting artifacts themselves. An understanding of workspace activity needs to include the role of gestural activity, and the use of the workspace to develop ideas and mediate interaction. A framework that helps illustrate an expanded view of workspace activity is proposed and supported with empirical data.
Overcoming computer phobia
Authors: Jean E. Thompson
Venue: ACM SIGUCCS Newsletter (1988)

After having worked in the College of Business computer labs at Pennsylvania State University for two and a half years, I developed a set of guidelines to follow when consulting students and faculty in the use of computers. Here are the guidelines:1. Always tell them to double the time that they plan to spend in the lab doing homework. This cuts down on the time pressure to get things done. Once a person feels pressure and begins to tense up, they forget to do what they have been taught, and are more likely to make more mistakes leading to frustration.
Computation of the axial view of a set of isothetic parallelepipeds
Authors: Franco P. Preparata, Jeffrey S. Vitter, Mariette Yvinec
Venue: ACM Transactions on Graphics (TOG) (1990)

We present a new technique to display a scene of three-dimensional isothetic parallelepipeds (3D-rectangles), viewed from infinity along one of the coordinate axes (axial view). In this situation, there always exists a topological sorting of the 3D-rectangles based on the relation of occlusion (a dominance relation). The arising total order is used to generate the axial view, where the two-dimensional view of each 3D-rectangle is incrementally added, starting from the closest 3D-rectangle. The proposed scene-sensitive algorithm runs in time O(N log2N + d log N), where N is the number of 3D-rectangles and d is the number of edges of the display. This improves over the previously best known technique based on the same approach.
Autonomous robot controller with a dual strategy of decision making
Authors: R. Bhatt, D. Gaw, A. Maystel
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

A real-time system for the control of an autonomous vehicle consisting of a nested hierarchy of control modules. The focus is on the PILOT module which provides the real-time guidance of the system. It is responsible for the generation and tracking of dynamically feasible trajectories which follow the planned path given by the upper level (NAVIGATOR) and avoiding local obstacles. This paper describes a system of guidance algorithms of &ldquo;pilot decision making&rdquo; which incorporates different strategies of operation. Depending on the set of circumstances including the level of &ldquo;informedness&rdquo;, initial data, concrete environment, and so on, the &ldquo;personality&rdquo; of PILOT is being selected between two alternatives: A diligent and thoroughful strategist which tends to explore all available trajectories off-line and be prepared to follow one of them precisely. A hasty decision maker inclined to make a choice of solution in a rather reckless manner base upon short term alternatives not regarding long term consequences. Simulation shows that these two personalities support each other in a beneficial way. This paper is based on the concept of Nested Hierarchical Controller [1,2]. Intelligent Mobile Autonomous System (IMAS) is considered to be controlled by a Planner-Navigator-Pilot type of an intelligent controller [3]. Only Pilot's level is analyzed. The concept of behavioral duality is a development of our prior papers exploring this level of a multiresolutional controller [4-6]. Pilot level with behavioral duality was thoroughly simulated in the Laboratory of Applied Machine Intelligence and Robotics (LAMIR) of Drexel University, and applied in the IMAS-2 (Drexel-Dune-Buggy) which has been developed under the contract with US Army.
From splines to fractals
Authors: R. Szeliski, D. Terzopoulos
Venue: ACM SIGGRAPH Computer Graphics (1989)

Deterministic splines and stochastic fractals are complementary techniques for generating free-form shapes. Splines are easily constrained and well suited to modeling smooth, man-made objects. Fractals, while difficult to constrain, are suitable for generating various irregular shapes found in nature. This paper develops constrained fractals, a hybrid of splines and fractals which intimately combines their complementary features. This novel shape synthesis technique stems from a formal connection between fractals and generalized energy-minimizing splines which may be derived through Fourier analysis. A physical interpretation of constrained fractal generation is to drive a spline subject to constraints with modulated white noise, letting the spline diffuse the noise into the desired fractal spectrum as it settles into equilibrium. We use constrained fractals to synthesize realistic terrain models from sparse elevation data.
Multichannel Texture Analysis Using Localized Spatial Filters
Authors: A. C. Bovik, M. Clark, W. S. Geisler
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

A computational approach for analyzing visible textures is described. Textures are modeled as irradiance patterns containing a limited range of spatial frequencies, where mutually distinct textures differ significantly in their dominant characterizing frequencies. By encoding images into multiple narrow spatial frequency and orientation channels, the slowly varying channel envelopes (amplitude and phase) are used to segregate textural regions of different spatial frequency, orientation, or phase characteristics. Thus, an interpretation of image texture as a region code, or carrier of region information, is emphasized. The channel filters used, known as the two-dimensional Gabor functions, are useful for these purposes in several senses: they have tunable orientation and radial frequency bandwidths and tunable center frequencies, and they optimally achieve joint resolution in space and in spatial frequency. By comparing the channel amplitude responses, one can detect boundaries between textures. Locating large variations in the channel phase responses allows discontinuities in the texture phase to be detected. Examples are given of both types of texture processing using a variety of real and synthetic textures.
CASE and the undergraduate curriculum
Authors: James R. Sidbury, Richard Plishka, John Beidler
Venue: ACM SIGCSE Bulletin (1989)

In 1987 the Dept. of Computer Science at the University of Scranton received an NSF CSIP grant to develop a Software Engineering Laboratory. A decision was made to supplement that laboratory with computer assisted software engineering (CASE) tools. This paper describes the on going integration of CASE tools into the computing curricula at the University of Scranton.
Image Seaming for Segmentation on Parallel Architecture
Authors: M.-H. Chen, T. Pavlidis
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

Some basic problems encountered when assembling the results of image analysis on architectures with coarse parallelism are discussed. The emphasis is on strategies that minimize the distortion in the final result caused by processing image tiles independently. Methods are presented that can be used to reduce the disparity between the results of processing each title independently and processing each as part of a whole image. A seaming algorithm has been constructed to seam the tiles with the results of region segmentation using the gray-level mean difference or maximum-minimum criteria. Experimental results, obtained on a Sequent machine and a Sun 3/160 workstation, are given to illustrate the performance of the algorithm.
An interactive system for seismic velocity analysis
Authors: C. A. Addison, J. M. Cook, L. R. Hagen
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications - Volume 2 (1989)

Seismic data processing is a time-consuming operation. Two main reasons for this are the large amounts of data, which have to be put in and taken out of the computer regularly, and the need for intervention by an expert at many intermediate stages. A subsidiary cause is the large amount of computation. The recent appearance of multiprocessor computers has created the opportunity to provide an interactive system to ease and speed-up the seismic data processing cycle. This paper describes the development of an initial interactive system for the velocity analysis and NMO/stacking stage of seismic processing. Computational power and storage are supplied by two 32-node Intel iPSC/1 Hypercubes, both with 16 memory nodes and 16 vector nodes. Each hypercube has 96 Mbytes of memory and a top processing speed of over 100 Mflops (32 bit). A SUN-3 Workstation is used to display intermediate results and to enable the expert to direct the processing more efficiently.
Vectorizing compilers: a test suite and results
Authors: D. Callahan, J. Dongarra, D. Levine
Venue: Proceedings of the 1988 ACM/IEEE conference on Supercomputing (1988)

This report describes a collection of 100 Fortran loops used to test the effectiveness of an automatic vectorizing compiler. We present the results of compiling these loops using commercially available, vectorizing Fortran compilers on a variety of supercomputers, mini-supercomputers, and mainframes.
A loop optimization technique based on scheduling table
Authors: D. Liu, W. K. Giloi
Venue: Proceedings of the 22nd annual workshop on Microprogramming and microarchitecture (1989)

Loop optimization is an important aspect of microcode compaction to minimize execution time. In this paper a new loop optimization technique for horizontal microprograms is presented, which makes use of the cyclic regularity of loops. We have extended the concept of reservation table, which is used to develop a pipeline control strategy, so that both data dependencies and resource conflicts are taken into account. Based on the analysis of the extended reservation table, or scheduling table, an optimal schedule can be obtained. The iterations of a loop are then rearranged to form a new loop body, whose length may be greater than that of the original one. But the average initiation latency between iterations is minimal.
A Simulation-Based Method for Generating Tests for Sequential Circuits
Authors: Kwang-Ting Cheng, Vishwani D. Agrawal
Venue: IEEE Transactions on Computers (1990)

In a recent work of the authors (1987), a simulation-based directed search approach for generating test vectors for combinational circuits was proposed. In this method, the search for a test vector is guided by a cost function computed by the simulator. Event-driven simulation deals with circuit delays in a very natural manner. Signal controllability information required for the cost function is incorporated in a new form of logic model called the threshold-value model. These concepts are extended to meet the needs of sequential circuit test generation. Such extensions include handling of unknown values, analysis of feedback loops, and analysis of race conditions in the threshold-value model. A threshold-value sequential test generation program, TVSET, is implemented. It automatically initializes the circuit and generates race-free tests for synchronous and asynchronous circuits.
Microcode compaction with timing constraints
Authors: B. Su, S. Ding, J. Wang, J. Xia
Venue: ACM SIGMICRO Newsletter (1988)

At present, microcode compaction with timing constraints (abbreviated as MCTC) is still an open problem. Complex timing relation between microoperations greatly affects the optimization result of microcode. This paper begins with a survey of MCTC problems, then presents a formal description of MCTC and, on the basis of a systematic study of the characteristics of HCTC, presents a generally-oriented heuristic algorithm--CAS, which has a high success rate of scheduling and promises a good optimization result. Preliminary experiments indicate that CAS is better than other existing MCTC algorithms.
Further Comments on 'Detection of Faults in Programmable Logic Arrays' by J.E. Smith
Authors: J. Jacob, N. N. Biswas
Venue: IEEE Transactions on Computers (1990)

In recent correspondence, L. Ye-Wei and J. Wei have shown two counterexamples that contradict theorems four and five of a paper by J.E. Smith. In his reply, Smith stated an additional condition under which the theorems hold good. The commenters provide a counterexample that contradicts Smith's modified theorem five. They provide another counterexample that contradicts theorem three of Smith's original paper. In his reply, Smith corrects an error in his treatment.
Simulation of object and human skin formations in a grasping task
Authors: J.-P. Gourret, N. M. Thalmann
Venue: ACM SIGGRAPH Computer Graphics (1989)

This paper addresses the problem of simulating deformations between objects and the hand of a synthetic character during a grasping process. A numerical method based on finite element theory allows us to take into account the active forces of the fingers on the object and the reactive forces of the object on the fingers. The method improves control of synthetic human behavior in a task level animation system because it provides information about the environment of a synthetic human and so can be compared to the sense of touch. Finite element theory currently used in engineering seems one of the best approaches for modeling both elastic and plastic deformation of objects, as well as shocks with or without penetration between deformable objects. We show that intrinsic properties of the method based on composition/decomposition of elements have an impact in computer animation. We also state that the use of the same method for modeling both objects and human bodies improves the modeling both objects and human bodies improves the modeling of the contacts between them. Moreover, it allows a realistic envelope deformation of the human fingers comparable to existing methods. To show what we can expect from the method, we apply it to the grasping and pressing of a ball. Our solution to the grasping problem is based on displacement commands instead of force commands used in robotics and human behavior.
Access methods for multiversion data
Authors: David Lomet, Betty Salzberg
Venue: ACM SIGMOD Record (1989)

We present an access method designed to provide a single integrated index structure for a versioned timestamped database with a non-deletion policy. Historical data (superceded versions) is stored separately from current data. Our access method is called the Time-Split B-tree. It is an index structure based on Malcolm Easton's Write Once B-tree. The Write Once B-tree was developed for data stored entirely on a Write-Once Read-Many or WORM optical disk. The Time-Split B-tree differs from the Write Once B-tree in the following ways: Current data must be stored on an erasable random-access device. Historical data may be stored on any random-access device, including WORMs, erasable optical disks, and magnetic disks. The point is to use a faster and more expensive device for the current data and a slower cheaper device for the historical data. The splitting policies have been changed to reduce redundancy in the structure&mdash;the option of pure key splits as in B+-trees and a choice of split times for time-based splits enable this performance enhancement. When data is migrated from the current to the historical database, it is consolidated and appended to the end of the historical database, allowing for high space utilization in WORM disk sectors.