ppxscal/embedding_network huggingface dataset:
On different modes of communication
Authors: Bernd Halstenberg, Rudiger Reischuk
Venue: Proceedings of the twentieth annual ACM symposium on Theory of computing (1988)

We compare the communication complexity of discrete functions under different modes of computation, unifying and extending several known models. Protocols can be deterministic, nondeterministic or probabilistic and in the last case the error probability may vary. On the other hand communication can be 1-way, 2-way or as an intermediate stage consist of a fixed number k > 1 of rounds. The following main results are obtained. A square gap between deterministic and nondeterministic communication complexity is shown for a specific function, which is the maximal possible. This improves the results of [MS 82] and [AUY 83]. For probabilistic 1- and 2-way protocols we prove linear lower bounds for functions that satisfy certain independence conditions, extending the results of [Y 79] and [Y 83]. Further, with more technical effort an exponential gap between deterministic k-round and probabilistic (k - 1)-round communication with fixed error probability is obtained. This generalizes the main result of [DGS 84]. On contrast for arbitrary error probabilities less than 1/2 there is no difference between the complexity of 1- and 2-way protocols, extending results of [PS 84]. Finally we consider communication with fixed message length and uniform probability distributions and give simulations of arbitrary protocols by such uniform ones with little overhead.
Dispatching in an integrated circuit wafer fabrication line
Authors: P. K. Johri
Venue: Proceedings of the 21st conference on Winter simulation (1989)

Wafer Fabrication has been described as the most complicated manufacturing environment existing today. This paper describes a method used to dispatch lots in one of AT&T's Wafer Fabrication Clean Rooms. The objective is to minimize idle time on important facilities in the clean room. For each lot in the clean room, the method indicates the slack time the lot can incur before it is needed at the next important facility group in its route. The slack time is the amount of time the lot can be delayed in queue with the implication that a lot with a smaller slack time needs to be processed more urgently than a lot with a larger slack time.
Multiple-knot and rational cubic beta-splines
Authors: Barry Joe
Venue: ACM Transactions on Graphics (TOG) (1989)

Goodman (Properties of Beta-splines. J. Approx. Theory 44, 2 (June 1985), 132-153) gave an explicit formula for cubic Beta-splines on a uniform knot sequence with varying &bgr;1 and &bgr;2 values at the knots. We establish an alternative explicit formula for cubic Beta-splines on a nonuniform knot sequence with constant &bgr;1 = 1 and varying &bgr;2 values at the knots. This alternative formula can also be used if the knot sequence contains multiple knots, and is useful for knot insertion. We show how to efficiently evaluate a cubic Beta-spline curve at many values using this formula. We introduce rational cubic Beta-spline curves and surfaces that have extra weight parameters for shape control, and show that they satisfy the same geometric continuity conditions and properties as nonrational cubic Beta-spline curves and surfaces.
The Capacity of Multilevel Threshold Functions
Authors: S. 'Olafsson, Y. S. Abu-Mostafa
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1988)

Lower and upper bounds for the capacity of multilevel threshold elements are estimated, using two essentially different enumeration techniques. It is demonstrated that the exact number of multilevel threshold functions depends strongly on the relative topology of the input set. The results correct a previously published estimate and indicate that adding threshold levels enhances the capacity more than adding variables.
Compaction of a routed channel on the connection machine
Authors: S. Ganguly, V. Pitchumani
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

A parallel algorithm for symbolic compaction of two layered channels has been developed and implemented on the Connection Machine. It allows fast channel compaction with very little wasted space.
On Smoothness of a Vector Field-Application to Optical Flow
Authors: A. Mitiche, R. Grisell, J. K. Aggarwal
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1988)

Two measures of smoothness of a vector field over a domain are suggested, together with associated smoothing operators that satisfy given constrains. The technique is illustrated using operators that smooth the invariants of optical flow curl and divergence, estimated from intensity profiles of moving nondeformable objects. The operators have been applied with satisfactory results to derived flow estimates with high noise levels.
High performance file system for supercomputing environment
Authors: H. Nishino, S. Naka, K. Ikumi, W. Leslie
Venue: Proceedings of the 1989 ACM/IEEE conference on Supercomputing (1989)

SUPER-UX is a high performance UNIX operating system for NEC SX-3/SX-X supercomputer and has many enhanced facilities to make available the maximum SX-3/SX-X computing power (peek speed of 22GFLOPS) to users. This paper presents the SUPER-UX file system, a strong point of SUPER-UX, which is based on the standard UNIX file system to satisfy scientific computing environment requirements for I/O performance and facilities.
Caught in the middle
Authors: S. Webster
Venue: Proceedings of the 17th annual ACM SIGUCCS conference on User Services (1989)

Cartoonist Sandra Boynton has captured in a single cartoon the dilemma faced by middle managers at all levels. The cartoon shows a bewildered, hapless cat standing between a large, pointing, barking dog on one side and a small, distraught yapping dog on the other. When you were promoted or promised promotion, you were probably not warned about all the ways in which you would be &ldquo;caught in the middle&rdquo;. In this presentation, I want to talk about some of the ways in which you can be in the middle.
The SIMPLEX operating system
Authors: D. W. Krumme
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications: Architecture, software, computer systems, and general issues - Volume 1 (1988)

This paper describes a new operating system for the NCUBE hypercube multiprocessor called SIMPLEX. It was developed with several objectives in mind: the provision of various innovative and useful services for application programs, the study of alternative paradigms for node-to-node communication, and the development of support tools for both real-time and offline debugging and performance monitoring. Like other node-operating systems for hypercubes, SIMPLEX is a local kernel running on each node, managing program execution and communication between nodes and providing services to node programs. Among the services available are a multi-process environment with dynamic process creation, priority-based scheduling, priority-based communication, several forms of interprocess and inter-node communication, and an emulation of the standard NCUBE operating system VERTEX for compatibility. SIMPLEX first became operational in the summer of 1987 and will be under active development throughout 1988. People interested in obtaining copies of it for their own use are encouraged to contact the author.
AutoMod II: the system builder
Authors: M. B. Thompson
Venue: Proceedings of the 21st conference on Winter simulation (1989)

AutoMod II (AM II) is an industrial simulation system that combines CAD-like drawing capabilities used to input movement systems with a powerful, engineering oriented, procedural language for the definition of control logic and material flow. AM II's CAD features are used to define the physical geometry of manufacturing, material handling, storage, and distribution systems. Unlike most other simulation packages, AM II's powerful graphical interface accurately captures the physical constraints of distance, size, and space. AM II also provides the user with a set of "expert based" movement systems that have been developed from ASI's real-world experience in industrial automation. As a result, a substantial portion of the underlying model logic is generated for the user from the graphics and the movement system input parameters. Furthermore, once the model is built, the 3-D animation is built as well, with no further work on the modeller's part. AM II's user environment provides unmatched productivity.AM II is an Engineering Workstation product that runs on Silicon Graphics, Intergraph, SUN, and DEC under the UNIXTM operating system. ASI has recently introduced an entry level version called AutoMod2e that runs on the Macintosh II under the Mac/OS.
Hierarchical planarity testing algorithms
Authors: Thomas Lengauer
Venue: Journal of the ACM (JACM) (1989)

Using hierarchical definitions, one can describe very large graphs in small space. The blow-up from the length of the hierarchical description to the size of the graph can be as large as exponential. If the efficiency of graph algorithms is measured in terms of the length of the hierarchical description rather than in terms of the graph size, algorithms that do not exploit the hierarchy become hopelessly inefficient. Whether the hierarchy can be exploited to speed up the solution of graph problems depends on the hierarchical graph model. In the literature, hierarchical graph models have been described that allow almost no exploitation of the hierarchy [ 16]. In this paper, a hierarchical graph model that permits taking advantage of the hierarchy is presented. For this model algorithms are given that test planarity of a hierarchically described graph in linear time in the length of the hierarchical description.
On Embedding Rectangular Grids in Hypercubes
Authors: M. Y. Chan, F. Y. L. Chin
Venue: IEEE Transactions on Computers (1988)

The following graph-embedding question is addressed: given a two-dimensional grid and the smallest hypercube with at least as many nodes as grid points, how can one assign grid points to hypercube nodes (with at most one grid point per node) so as to keep grid neighbors near each other in the cube? An embedding scheme for an infinite class of two-dimensional grids is given that keeps grid neighbors within a distance of two apart.
Relating total and partial correctness interpretations of non-deterministic programs
Authors: Carl A. Gunter
Venue: Proceedings of the 17th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1989)

The purpose of this paper is to discuss the relationship between the interpretations of non-deterministic programs using the upper (total correctness) powerdomain on the one hand and the lower (partial correctness) powerdomain on the other. It is shown that there is a close semantic relationship between these two interpretations which suggests the formulation of a new operator called the mixed powerdomain. It is shown that the mixed powerdomain has many pleasing domain-theoretic and algebraic properties. The mixed powerdomain is closely related to new powerdomains which have been recently investigated as mathematical models of partial information in databases. Some of the basic intuitions captured by such structures may have uses for the specification of non-deterministic computations. The paper includes a sample non-deterministic programming language and a semantics using the mixed powerdomain.
The number of buffers required for sequential processing of a disk file
Authors: Alon Itai, Yoav Raz
Venue: Communications of the ACM (1988)

The number of buffers required for sequential processing of disk files is investigated with the assumption that there is a single user served by two processors: one reads blocks from the disk into buffers in main memory, while the other processor processes the buffers. If processing is faster than reading, then two buffers suffice. However, if processing is slower, using only two buffers does not guarantee minimum completion time. The minimal required number of buffers is calculated in this article.
Coherent parallel C
Authors: E. W. Felten, S. W. Otto
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications: Architecture, software, computer systems, and general issues - Volume 1 (1988)

Coherent Parallel C (CPC) is an extension of C for parallelism. The extensions are not simply parallel for loops; instead, a data parallel programming model is adopted. This means that one has an entire process for each data object. An example of an &ldquo;object&rdquo; is one mesh point in a finite element solver. How the processes are actually distributed on a parallel machine is transparent&mdash;the user is to imagine that an entire processor in a distributed-memory environment is dedicated to each process. This simplifies programming tremendously: complex if statements associated with domain boundaries disappear; problems which do not exactly match the machine size and irregular boundaries are all handled transparently. The usual communication calls are not seen at all at the user level. Variables of other processes (which may or may not be on another processor) are merely accessed (global memory). The first pass of the CPC compiler schedules the necessary communications in an efficient, coherent manner. Processes in CPC are insulated from one another and interact in a deterministic manner. This allows tractable debugging. Standard C I/O is provided, with simple extensions for parallelism. We currently have a CPC runtime system implemented on an NCUBE and have started implementing a true compiler for the language. CPC is not specific to distributed memory machines. Implementation of this language on other architectures is natural&mdash;for example, there seems to be no fundamental problem with CPC on shared-memory parallel computers.
Making APL error messages kinder and gentler
Authors: W. J. Shaw
Venue: ACM SIGAPL APL Quote Quad (1989)

Emulating the overall design of APL, the error messages generated by APL interpreters are formal and succinct. Because of this one gets the feeling the interpreter is not telling all that it knows. It is urged that error messages be made more revealing, and, hence, more user-friendly.
High speed high quality antialiased vector generation
Authors: Anthony C. Barkans
Venue: Proceedings of the 17th annual conference on Computer graphics and interactive techniques (1990)

A vector generation method is described in which a high quality image rendering scheme is coupled with a high speed scan-conversion algorithm.The rendering scheme consists of two parts. First a prefiltering method is used to antialias the vectors. Second a compositing technique is used to compose the vectors into the frame-buffer.The scan-conversion algorithm presented allows a single vector to be scan-converted by a either by a single processor or a set of processors running in parallel. When using parallel processors, antialiased vectors may be scan-converted and written to a frame store at the same high speed as aliased vectors. The VLSI technology used to implement this algorithm is capable of drawing over two million high quality antialiased vectors per second.
A Cost Model for Determining the Optimal Number of Software Test Cases
Authors: David B. Brown, Saeed Maghsoodloo, William H. Deason
Venue: IEEE Transactions on Software Engineering (1989)

A probabilistic model is presented that demonstrates the optimal number of software test cases required in situations where the following can be estimated as independent parameters: (1) the cost per test; (2) the cost per error if undetected until field implementation; (3) the number of software executions over its lifetime; (4) the number of possible different executions; and (5) the number of faults embedded in the software. A formula is derived by the use of calculus and is solved by approximation techniques. Tables of the optimal number of tests over a range of parameter values are presented to illustrate the results. The model serves as a basis for further research efforts to improve the accuracy of input variable estimation.
A CASE primer for computer science educators
Authors: Barbee T. Mynatt, Laura Marie Leventhal
Venue: ACM SIGCSE Bulletin (1989)

The continuing demand for the development of new software and maintenance of existing software has made productivity an important issue in the software industry. In the past, increases in productivity have come from the introduction of software engineering techniques. Today, software engineers are looking to CASE (computer-aided software engineering) tools as a possible source of further improvements in productivity. This paper provides an overview of current CASE tools, with a focus on three types of tools: framing environments, programming environments and general environments. Two specific CASE systems are discussed in some detail. CASE systems in the context of software engineering education are also discussed.
The use of hypertext to support user services
Authors: D. E. Ricket
Venue: Proceedings of the 17th annual ACM SIGUCCS conference on User Services (1989)

This paper defines hypertext in general and discusses its potential in a user services setting. Hypertext systems are contrasted with expert systems, particularly on the dimensions of &ldquo;user control&rdquo; and professional responsibility. Several actual hypertext systems utilized by user services staff and that show potential for increasing the timeliness and quality of client service as well as a reduction in staff work load are described.
More efficient computation of the complex error function
Authors: G. P. M. Poppe, C. M. J. Wijers
Venue: ACM Transactions on Mathematical Software (TOMS) (1990)

Gautschi has developed an algorithm that calculates the value of the Faddeeva function w(z) for a given complex number z in the first quadrant, up to 10 significant digits. We show that by modifying the tuning of the algorithm and testing the relative rather than the absolute error we can improve the accuracy of this algorithm to 14 significant digits throughout almost the whole of the complex plane, as well as increase its speed significantly in most of the complex plane. The efficiency of the calculation is further enhanced by using a different approximation in the neighborhood of the origin, where the Gautschi algorithm becomes ineffective. Finally, we develop a criterion to test the reliability of the algorithm's results near the zeros of the function, which occur in the third and fourth quadrants.
ACORN: APL to C on real numbers
Authors: Robert Bernecky Charles Brenner Stephen B. Jaffe, George P. Moeckel
Venue: ACM SIGAPL APL Quote Quad (1990)

a prototype APL to C compiler (ACORN: APL to C On Real Numbers) was produced while investigating improved tools for solving numerically intensive problems on supercomputers. ACORN currently produces code which runs slower than hand-coded Cray FORTRAN, but we have identified the major performance bottlenecks, and believe we know how to remove them. Although created in a short time on a limited budget, and intended only as a proof of the feasibility of compiling APL for numerically intensive environments, ACORN has shown that straightforward compiled APL will be able to compete with hand-optimized FORTRAN in many common supercomputer applications.
Introduction to special section on software testing
Authors: R. Hamlet
Venue: Communications of the ACM (1988)

The field of software testing spans mathematical theory, the art and practice of validation, and methodology of software development. To cover this range would require a textbook (or several texts), not a trio of articles. But the work presented in this special section is a kind of "test set." Each paper is a significant contribution within one of the three broad areas. The reader must now make the assessment that is critical to any review of test points: are they representative? My own answer is 'no'; these articles are provocative and revealing rather than routine summaries. And perhaps that is what software testing is all about: good tests are the ones that provide new insights, not the ones that cover well worn ground.
A fast adaptive grid scheme for elliptic partial differential equations
Authors: Calvin J. Ribbens
Venue: ACM Transactions on Mathematical Software (TOMS) (1989)

We describe the Recursive Subdivision (RS) method-an efficient and effective adaptive grid scheme for two-dimensional elliptic partial differential equations (PDEs). The RS method generates a new grid by recursively subdividing a rectangular domain. We use a heuristic approach which attempts to equidistribute a given density function over the domain. The resulting grid is used to generate an adaptive grid domain mapping (AGDM), which may be applied to transform the PDE problem to another coordinate system. The PDE is then solved in the transformed coordinate system using a uniform grid. We believe parallelism is most easily exploited when computations are carried out on uniform grids; the AGDM framework allows the power of adaptation to be applied while still preserving this uniformity. Our method generates good adaptive grid domain mappings at a small cost compared to the cost of the entire computation. We describe the RS algorithm in detail, briefly describe the AGDM framework, and illustrate the effectiveness of our scheme on several realistic test problems.
A technique for two-dimensional pattern matching
Authors: Rui Feng Zhu, Tadao Takaoka
Venue: Communications of the ACM (1989)

By reducing an array matching problem to a string matching problem in a natural way, it is shown that efficient string matching algorithms can be applied to arrays, assuming that a linear preprocessing is made on the text.
A note on Lamport's mutual exclusion algorithm
Authors: Tai-Kuo Woo
Venue: ACM SIGOPS Operating Systems Review (1990)

The Lamport's mutual exclusion exclusion algorithm, also known as the bakery algorithm, is very simple and easy to implement. However, the ticket numbers assigned to the processes wishing to enter the critical section can become indeterminately large. This paper resolves this problem by allowing the ticket numbers to move around a ring of length 2N, where N is the number of processes. The comparison of two ticket numbers is based the distance between them and their magnitudes.
IOStone: a synthetic file system benchmark
Authors: Arvin Park, Jeffrey C. Becker, Richard J. Lipton
Venue: ACM SIGARCH Computer Architecture News (1990)

This paper presents a portable benchmark called IOStone that measures file system performance on a string of file system requests that is representative of measured system loads. Instead of isolating a particular aspect of file system performance such as disk access speed, or channel bandwidth, IOStone measures performance of the entire file system which includes components of disk performance, CPU performance on file system tasks, and disk cache performance, IOStone provides a basis for comparing performance of different file system implementations. It can also guide system builders in matching processor performance with file system performance. Measurements made using the IOStone benchmark indicate that a good balance between processor performance and file system performance is rarely achieved. Version II of the C language version of IOStone is available through electronic mail from becker@iris.ucdavis.edu.