ppxscal/embedding_network huggingface dataset:
Inherently Lower-Power High-Performance Superscalar Architectures
Authors: Victor V. Zyuban, Peter M. Kogge
Venue: IEEE Transactions on Computers (2001)

In recent years, reducing power has become an important design goal for high-performance microprocessors. This work attempts to bring the power issue to the earliest phases of microprocessor development, in particular, the stage of defining a chip microarchitecture. We investigate power-optimization techniques of superscalar microprocessors at the microarchitecture level that do not compromise performance. First, major targets for power reduction are identified within microarchitecture, where power is heavily consumed or will be heavily consumed in next-generation superscalar processors. Then, a new, energy-efficient version of a multicluster microarchitecture is developed that reduces energy in the identified critical design points with minimal performance impact. A methodology is developed for energy-performance optimization at the microarchitecture level that generates, for a microarchitecture, a set of energy-efficient configurations, forming a convex hull in the power-performance space. Detailed simulation of the baseline and proposed multicluster architectures has been performed using the developed optimization methodology. A comparison of the two microarchitectures, both optimized for energy efficiency, shows that the multicluster architecture is potentially up to twice as energy efficient for wide issue processors, with an advantage that grows with the issue width. Conversely, at the same power dissipation level, the multicluster architecture supports configurations with measurably higher performance than equivalent conventional designs.
Some thoughts on undergraduate teaching and the Ph.D.
Authors: Doug Baldwin
Venue: ACM SIGCSE Bulletin (2000)

As the hiring crisis in academic computer science worsens, many people ask whether faculty whose primary job is teaching need doctorates. In the past, the answer would have been "yes;" now people increasingly suggest that it could be "no." I have argued in my own department for hiring only faculty with doctorates, because, while the doctorate does not directly train people to teach, it does seem to correlate with many characteristics of a good educator. This paper explores the thinking underlying my view, in hopes that it may help others clarify the needs and reasoning behind their own faculty searches.
The Computer Museum member's first field trip: the Northbay AN/FSQ7 SAGE site
Authors: Gordon Bell
Venue: Communications of the ACM (1983)

The Computer Museum's first considered priority is to save history, the second is to display it, and the third is to interpret its historic role.
Secure notarization of paper text documents
Authors: Matthias Ruhl, Marshall Bern, David Goldberg
Venue: Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms (2001)

We present a method to notarize a paper document. This method computes a set of features from the page, inputs these features into a hash function, digitally signs the output, and then prints the resulting signature on the page. The notarized document is self-contained: verification does not require reference to online information.
On the discrete Bak-Sneppen model of self-organized criticality
Authors: Jérémy Barbay, Claire Kenyon
Venue: Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms (2001)

We propose a discrete variant of the Bak-Sneppen model for self-organized criticality. In this process, a configuration is an n-bit word, and at each step one chooses a random bit of minimum value (usually a zero) and replaces it and its two neighbors by independent Bernoulli variables with parameter p. We prove bounds on the average number of ones in the stationary distribution and present experimental results.
The IITRAN programming language
Authors: Robert B. K. Dewar, Ronald R. Hochsprung, William S. Worley
Venue: Communications of the ACM (1969)

The IITRAN language, developed to be used by students, and its important features are described. IITRAN is a procedure-oriented language with a one-level block structure and a variety of data types. Several novel and powerful features are included. A discussion of design principles to be followed in a student language is given.
A comparison of three programming models for adaptive applications on the Origin2000
Authors: Hongzhang Shan, Jaswinder P. Singh, Leonid Oliker, Rupak Biswas
Venue: Proceedings of the 2000 ACM/IEEE conference on Supercomputing (CDROM) (2000)

Adaptive applications have computational workloads and communication patterns which change unpredictably at runtime, requiring load balancing to achieve scalable performance on parallel machines. Efficient parallel implementation of such adaptive application is therefore a challenging task. In this paper, we compare the performance of and the programming effort required for two major classes of adaptive applications under three leading parallel programming models on an SGI Origin 2000 system, a machine which supports all three models efficiently. Results indicate that the three models deliver comparable performance. However, the implementations differ significantly beyond merely using explicit messages versus implicit loads/stores even though the basic parallel algorithms are similar. Compared with the message-passing (using MPI) and SHMEM programming models, the cache-coherent shared address space (CC-SAS) model provides substantial ease of programming at both the conceptual level and program orchestration levels, often accompanied by performance gains. However, CC-SAS currently has portability limitations and may suffer from poor spatial locality of physically distributed shared data on large numbers of processors.
Error messages: the neglected area of the man/machine interface
Authors: P. J. Brown
Venue: Communications of the ACM (1983)

The quality of error messages produced by software used in the field was tested by a simple experiment; it was found to be far from adequate. The results of the experiment are analyzed, and some responses which tend to collaborate the original findings are discussed. Finally, some suggestions are made for improving the quality of error messages.
An empirical evaluation of several methods to select the best system
Authors: Koichiro Inoue, Stephen E. Chick, Chun-Hung Chen
Venue: ACM Transactions on Modeling and Computer Simulation (TOMACS) (1999)

Simulation is an important tool for comparing the performance of several alternative systems. There is therefore significant interest in procedures that efficiently select the best system, where best is defined by the maximum or minimum expected simulation output. In this paper, we examine both two-stage and sequential procedures that represent three structurally different modeling methodologies for allocating simulation replications to identify the best system, and we evaluate them empirically with respect to several measures of effectiveness. Empirical evidence suggests that sequential procedures perform better than their two-stage counterparts, including a heuristic sequential variation on Rinott's procedure. Further, there appears to be significant benefit to using procedures based on a Bayesian, average-case analysis as opposed to the statistically-conservative indifference-zone formulation.
Globally constrained power control across mulitple channels in wireless data networks
Authors: Nicholas Bambos, Sunil Kandukuri
Venue: Mobile Networks and Applications (2001)

We investigate multi-channel transmission schemes for packetized wireless data networks. The transmitting unit transmits concurrently in several orthogonal channels (for example, distinct FDMA bands or CDMA codes) with randomly fluctuating interference and there is a global constraint on the total power transmitted across all channels at any time slot. Incoming packets to the transfer are queued up in separate buffers, depending on the channel they are to be transmitted in. In each time slot, one packet can be transmitted in each channel from its corresponding queue. The issue is how much power to transmit in each channel, given the interference in it and the packet backlog, so as to optimize various power and delay costs associated with the system. we formulate the general problem taking a dynamic programming approach. Through structural decomposition of the problem, we design practical novel algorithms for allocating power to various channels under the global constraint.
Programming Techniques: Regular expression search algorithm
Authors: Ken Thompson
Venue: Communications of the ACM (1968)

A method for locating specific character strings embedded in character text is described and an implementation of this method in the form of a compiler is discussed. The compiler accepts a regular expression as source language and produces an IBM 7094 program as object language. The object program then accepts the text to be searched as input and produces a signal every time an embedded string in the text matches the given regular expression. Examples, problems, and solutions are also presented.
Programmed error correction on a decimal computer
Authors: G. M. Weinberg
Venue: Communications of the ACM (1961)

In a previous paper [1], B. Dimsdale and I reported on the use of programmed Hamming codes for error correction on a 7090. The paper generated much interest, but several readers remarked that they could not use the technique on their decimal machines since they could not manipulate the bit structure of the characters. This paper presents a modification of Hamming's technique to adapt it to such machines. It generalizes to any number base for which addition is built into the machine, and so could be used for alphabetic error correction on a machine where such operations as (A + B, literally) or (R+2, literally) or (H + $, literally) are unequivocally defined. The technique will be described for single strings of characters, but may be generalized to parallel techniques if parallel, no-carry addition is available on the machine in question.
Solutions for H_{\infty} Filtering of Two-DimensionalSystems
Authors: Chunling Du, Lihua Xie, Cishen Zhang
Venue: Multidimensional Systems and Signal Processing (2000)

This paper deals with the H_{\infty} filtering problem for linear discrete-time two-dimensional (2-D) systems described by the Roesser model. It firstly establishes a version of the bounded real lemma to give a sufficient condition for quantification of the H_\infty noise attenuation for 2-D systems. Based on the bounded real lemma, the H_\infty filtering problem is investigated for filters of an observer-based structure or a general state equation form and the solutions are obtained in terms of Riccati inequalities or linear matrix inequalities. The design approach is illustrated by an example of a stationary field in image processing.
Person-matching by electronic methods
Authors: William Phillips,  Jr., Anita K. Bahn, Mabel Miyasaki
Venue: Communications of the ACM (1962)

Record linkage in the updating of files is accomplished in many establishments through the use of a preassigned number, such as payroll number, customer number, or social security number. In vital and health records, however, a unique number is generally not preassigned to an individual for purposes of reporting services received to the health department. In order to determine whether different physician reports refer to the same individual, name and other identification must be compared. This is a laborious operation which is subject to various errors because of name misspellings, changes of name upon marriage, and other problems. We are interested in the maintenance of a psychiatric case register in Maryland, where many of the reports from over a hundred psychiatric agencies refer to the same patient. These records must be linked in order to provide unduplicated counts of individuals under care and longitudinal records of psychiatric history. An earlier paper [1] describes our general procedures for register maintenance by use of a digital computer (Honeywell 800). Here we present in more detail our initial procedures for the person-matching process in order to elicit comments and suggestions from persons who have had experience in matching.
Some remarks on the syntax of symbolic programming languages
Authors: Alfonso Caracciolo Di Forino
Venue: Communications of the ACM (1963)

This paper concerns some preliminary results of an investigation of certain syntactical features of symbolic programming languages (SPL), which is a part of a wider research in the field of problem-oriented languages for automatic processor construction [1]. Our main aim is to point out certain peculiar features of SPL's which yield a deeper insight into their linguistic nature from a formal point of view, in order to take further steps in the direction of finding a proper way to define them. The general approach suggested here might be of some interest in the broader field of general linguistics, since many languages, including natural languages, show similar properties.
Perturbations of eigenvalues of non-normal matrices
Authors: A. van der Sluis
Venue: Communications of the ACM (1975)

The problem considered is to give bounds for finite perturbations of simple and multiple eigenvalues &lgr;i of nonnormal matrices, where these bounds are in terms of the eigenvalues {&lgr;i}, the departure from normality &sgr;, and the Frobenius norm &Verbar; &Dgr;A &Verbar; F of the perturbation matrix, but not in terms of the eigensystem. The bounds which are derived are shown to be almost attainable for any set of all matrices of given {&lgr;i} and &sgr;. One conclusion is that, very roughly speaking, a simple eigenvalue &lgr;1 is perturbed by |&Dgr;&lgr;1| &lsim; &Verbar; &Dgr;A &Verbar;F &middot; &prod; (&sgr;/&thgr;j) where &thgr;j is of the order of magnitude of |&lgr;1 - &lgr;j|, the product being extended over all j where &thgr;j &lsim; &sgr;.
Empirical Studies of a Prediction Model for Regression Test Selection
Authors: Mary Jean Harrold, David Rosenblum, Gregg Rothermel, Elaine Weyuker
Venue: IEEE Transactions on Software Engineering (2001)

Regression testing is an important activity that can account for a large proportion of the cost of software maintenance. One approach to reducing the cost of regression testing is to employ a selective regression testing technique that 1) chooses a subset of a test suite that was used to test the software before the modifications, then 2) uses this subset to test the modified software. Selective regression testing techniques reduce the cost of regression testing if the cost of selecting the subset from the test suite together with the cost of running the selected subset of test cases is less than the cost of rerunning the entire test suite. Rosenblum and Weyuker recently proposed coverage-based predictors for use in predicting the effectiveness of regression test selection strategies. Using the regression testing cost model of Leung and White, Rosenblum and Weyuker demonstrated the applicability of these predictors by performing a case study involving 31 versions of the KornShell. To further investigate the applicability of the Rosenblum-Weyuker (RW) predictor, additional empirical studies have been performed. The RW predictor was applied to a number of subjects, using two different selective regression testing tools, DejaVu and TestTube. These studies support two conclusions. First, they show that there is some variability in the success with which the predictors work and second, they suggest that these results can be improved by incorporating information about the distribution of modifications. It is shown how the RW prediction model can be improved to provide such an accounting.
Some realities of data administration
Authors: Beverly K. Kahn
Venue: Communications of the ACM (1983)

Little information exists on the practice of data administration, i.e., the management of data as an enterprise resource. A survey of data administrators at predominantly large enterprises was conducted to determine the extent of the existence of data administration and to assess its effectiveness as implemented. New insight into the realities of data administration, including its real-world objectives and perceived effectiveness, is presented.
Fast computation of linear generators for matrix sequences and application to the block Wiedemann algorithm
Authors: Emmanuel Thomé
Venue: Proceedings of the 2001 international symposium on Symbolic and algebraic computation (2001)

In this paper we describe how the half-gcd algorithm can be adapted in order to speed up the sequential stage of Coppersmith's block Wiedemann algorithm for solving large sparse linear systems over any finite field. This very stage solves a sub-problem than can be seen as the computation of a linear generator for a matrix sequence. Our primary realm of interest is the field Fq for large prime power q. For the solution of a N &times; N system, the complexity of this sequential part drops from &Ogr;(N2) to &Ogr;(M(N) log N) where M(d) is the cost for multiplying two polynomials of degree d. We discuss the implications of this improvement for the overall cost of the block Wiedemann algorithm and how its parameters should be chosen for best efficiency.
A graphical service system with variable syntax
Authors: Lawrence G. Roberts
Venue: Communications of the ACM (1966)

Man-machine interaction in many fields of endeavor should be greatly facilitated in the near future through the use of interactive graphical languages. To provide a variety of display scope communication procedures, a Graphic Service System which functions as a generalized graphical language translator, is being developed to aid the definition as well as the use of new graphical languages.
A region-based memory manager for prolog
Authors: Henning Makholm
Venue: ACM SIGPLAN Notices (2001)

We extend Tofte and Talpin's region-based model for memory management to support backtracking and cuts, which makes it suitable for use with Prolog and other logic programming languages. We describe how the extended model can be implemented and report on the performance of a prototype implementation. The prototype implementation performs well when compared to a garbage-collecting Prolog implementation using comparable technology for non-memory-management issues.
The use of hop-limits to provide survivable ATM group communications
Authors: William Yurcik, David Tipper, Deepankar Medhi
Venue: Proceedings of NGC 2000 on Networked group communication (2000)

We examine the use of a hop-limit constraint with techniques to provide survivability for connection-oriented ATM group communications. A hop-limit constraint is an approach that has evolved from solving point-to-point routing problems but has not been fully developed for group communications. A hop-limit: (1) limits the number of routes considered such that the routing problems of higher order complexity can be solved and (2) limits the length of any individual route to meet specific Quality of Service guarantees (such as delay). This paper focuses on the former. We compare the feasibility and cost of providing survivability using working multipoint routes with disjoint dedicated backup multipoint routes, where the multipoint routes are setup using either Self-Healing Rings, Shared Multicast Trees, or VC Meshes. We found that hop-limit constraints allowed us to exactly solve NP-complete routing problem on real networks.
An observation on bisection software for the symmetric tridiagonal eigenvalue problem
Authors: Linda Kaufman
Venue: ACM Transactions on Mathematical Software (TOMS) (2000)

In this article we discuss a small modification of the bisection routines in EISPACK and LAPACK for finding a few of the eigenvalues of a symmetric tridiagonal matrix A. When the principal minors of the matrix A yield good approximations to the desired eigenvalues, these modifications can yield about 30% reduction in the computation times.
Eigenvalues of a symmetric 3 &times; 3 matrix
Authors: Oliver K. Smith
Venue: Communications of the ACM (1961)

Recently, in order to find the principal moments of inertia of a large number of rigid bodies, it was necessary to compute the eigenvalues of many real, symmetric 3 &times; 3 matrices. The available eigenvalue subroutines seemed rather heavy weapons to turn upon this little problem, so an explicit solution was developed. The resulting expressions are remarkably simple and neat, hence this note.
Improved Data Structures for Fully Dynamic Biconnectivity
Authors: Monika R. Henzinger
Venue: SIAM Journal on Computing (2000)

We present fully dynamic algorithms for maintaining the biconnected components in general and plane graphs.A fully dynamic algorithm maintains a graph during a sequence of insertions and deletions of edges or isolated vertices. Let m be the number of edges and n be the number of vertices in a graph. The time per operation of the best deterministic algorithms is $O(\sqrt n)$ in general graphs and O(log n) in plane graphs for fully dynamic connectivity and O(min m2/3,n}) in general graphs and $O(\sqrt n)$ in plane graphs for fully dynamic biconnectivity. We improve the later running times to $O(\sqrt {m\log n})$ in general graphs and O(log 2 n) in plane graphs. Our algorithm for general graphs can also find the biconnected components of all vertices in time O(n).
OBDD Minimization Based on Two-Level Representation of Boolean Functions
Authors: Yu-Liang Wu, Hongbing Fan, Malgorzata Marek-Sadowska, C. k. Wong
Venue: IEEE Transactions on Computers (2000)

In this paper, we analyze the basic properties of some Boolean function classes and propose a low complexity OBDD variable ordering algorithm, which is exact (optimum) to some classes of functions and very effective to general two-level form functions. We show that the class of series-parallel functions, which can be expressed by a factored form where each variable appears exactly once, can yield exact OBDD variable orderings in polynomial time. We also study the thin Boolean functions whose corresponding OBDDs can be represented by the form of thin OBDDs in which the number of nonterminal nodes is equal to the number of input variables. We show that a thin Boolean function always has an essential prime cube cover and the class of series-parallel functions is a proper subset of thin Boolean functions. We propose a heuristic viewing OBDDs as evaluation machines with function cube covers as their inputs and apply a queuing principle in the algorithm design. Our heuristic, the augmented Dynamic Shortest Cube First algorithm, is proven to be optimum for the series-parallel functions and also be very effective for general two-level form functions. Experimental results on a large number of two-level form benchmark circuits show that the algorithm yields an OBDD total size reduction of over 51 percent with only 7 percent CPU time compared to the well-known network-based Fan-In Heuristic implemented in the SIS package. Comparing to the known exact results, ours is only 49 percent larger in size while only uses 0.001 percent CPU time.
Rethinking CS0 with JavaScript
Authors: David Reed
Venue: Proceedings of the thirty-second SIGCSE technical symposium on Computer Science Education (2001)

Traditional approaches to CS0 have emphasized either breadth, through an overview of computer science, or depth, through intensive programming. This paper describes an alternative teaching method that strikes a balance between these two approaches through the use of JavaScript and the World Wide Web. By taking advantage of JavaScript's simplicity and natural Web-based interfaces, the CS0 course described here is able to maintain a strong emphasis on programming and problem-solving, integrate programming skills with Web technology, and still provide reasonable breadth on general computer science topics. This balance between depth and breadth makes the course attractive to both non-majors and majors alike, providing a broad perspective of the field as well as a foundation for continuing studies in computer science.