ppxscal/embedding_network huggingface dataset:
Algorithm 419: zeros of a complex polynomial [C2]
Authors: M. A. Jenkins, J. F. Traub
Venue: Communications of the ACM (1972)

The subroutine CPOLY is a Fortran program to find all the zeros of a complex polynomial by the three-stage complex algorithm described in Jenkins and Traub [4]. (An algorithm for real polynomials is given in [5].) The algorithm is similar in spirit to the two-stage algorithms studied by Traub [1, 2]. The program finds the zeros one at a time in roughly increasing order of modulus and deflates the polynomial to one of lower degree. The program is extremely fast and the timing is quite insensitive to the distribution of zeros. Extensive testing of an Algol version of the program, reported in Jenkins [3], has shown the program to be very reliable.
Hands-on dance project (poster session): creative dance collaborations online
Authors: Sita Popat, Kia Ng, Jacqueline Smith-Autard
Venue: Proceedings of the third international conference on Collaborative virtual environments (2000)

This paper describes the extension of the creative, collaborative dance-making process via the Internet. The Hands-On Dance Project is a research project based on the World Wide Web. It facilitates collaboration between Internet users, regardless of their previous experience of dance, in the creation of danceworks through the Internet s communication and multimedia capabilities.
An approach to the optimum design of computer graphics systems
Authors: James D. Foley
Venue: Communications of the ACM (1971)

Display system designers are faced with the difficult task of selecting major subsystems in an intelligent way. Each subsystem is chosen from large numbers of alternatives; the selection is based on considerations such as system response time, system cost, and the distribution of data storage and processing between the graphics processor and its supporting data processing system. The work reported here develops an objective, quantitative design procedure and helps give a better understanding of how to configure display systems. This is accomplished by means of a mathematical model of a computer driven graphics system. The parameters of the model are functions of the capabilities of the graphics hardware and of the computational requirements of the graphics application. The model can be analyzed using numerical queueing analysis or simulation to obtain an average response time prediction. By combining the model with an optimization, the best graphics system configuration, subject to a cost constraint, is found for several applications. The optimum configurations are in turn used to find general display system design guidelines.
Exploiting space and location as a design framework for interactive mobile systems
Authors: Alan Dix, Tom Rodden, Nigel Davies, Jonathan Trevor, Adrian Friday, Kevin Palfreyman
Venue: ACM Transactions on Computer-Human Interaction (TOCHI) (2000)

This article considers the importance of context in mobile systems. It considers a range of context-related issues and focus on location as a key issue for mobile systems. A design framework is described consisting of taxonomies of location, mobility, population, and device awareness. The design framework inorms the construction of a semantic model of space for mobile systems. The semantic model is reflected in a computational model built on a distriuted platform that allows contextual information to be shared across a number of mobile devices. The framework support the design of interactive mobile systems while the platform supports their rapid development.
More on extensible machines
Authors: Gene F. Leonard, John R. Goodroe
Venue: Communications of the ACM (1966)

One of the most salient characteristics of extensible machines (EM) is the facility for providing system control over program-to-program and program-to-data linkage (e.g., address connection.) It is the intent of this paper to expand and clarify the remarks concerning program-to-program and program-to-data linkage that were embodied in the authors' previous paper on the EM concepts, and to, finally, trace the employment of linkage mechanisms through various levels of programming languages.
Explaining the Persistence of Commodity Prices
Authors: Serena Ng, Francisco J. Ruge-Murcia
Venue: Computational Economics (2000)

This paper extends the Competitive Storage Model by incorporating prominent features of the production process and financial markets. This extension seems necessary since the basic model does not successfully explain the degree of serial correlation observed in actual data. To generate a high degree of price persistence, the model must incorporate agents that are willing to hold stocks more often than predicted by the basic model, so we include characteristics of the production and trading mechanisms to provide the required incentives. Specifically, we introduce (i) gestation lags in production with heteroskedastic supply shocks, (ii) multiperiod forward contracts, and (iii) a convenience return to inventory holding. Rational expectations solutions for twelve commodities are solved numerically. Simulations are then used to assess the effects of these extensions on the time-series properties of commodity prices. The results indicate that each feature accounts partly for the persistence as well as the occasional spikes observed in actual data. Evidence is also presented that the precautionary demand for stocks might play a substantial role in the dynamics of commodity prices.
The effect of reconfigurable units in superscalar processors
Authors: Jorge E. Carrillo, Paul Chow
Venue: Proceedings of the 2001 ACM/SIGDA ninth international symposium on Field programmable gate arrays (2001)

This paper describes OneChip, a third generation reconfigurable processor architecture that integrates a Reconfigurable Functional Unit (RFU) into a superscalar Reduced Instruction Set Computer (RISC) processor's pipeline. The architecture allows dynamic scheduling and dynamic reconfiguration. It also provides support for pre-loading configurations and for Least Recently Used (LRU) configuration management.To evaluate the performance of the OneChip architecture, several off-the-shelf software applications were compiled and executed on Sim-OneChip, an architecture simulator for OneChip that includes a software environment for programming the system. The architecture is compared to a similar one but without dynamic scheduling and without an RFU. OneChip achieves a performance improvement and shows a speedup range from 2.16 up to 32 for the different applications and data sizes used. The results show that dynamic scheduling helps performance the most on average, and that the RFU will always improve performance the best when most of the execution is in the RFU.
Aggresors alignment for worst-case coupling noise
Authors: L. H. Chen, M. Marek-Sadowska
Venue: Proceedings of the 2000 international conference on Computer-aided design (2001)

In this paper we study signal alignment resulting in maximum peak interconnect crosstalk noise. We consider two cases. In the first one we assume that arbitrary arrival times of input signals are feasible. In the second case we assume that timing windows are given for each aggressor input. We propose a simple procedure to find aggressor alignment for worst-case coupling in both cases.
Computer generation of gamma random variables&mdash;II
Authors: Pandu R. Tadikamalla
Venue: Communications of the ACM (1978)

A rejection method is proposed for generating gamma variates with nonintegral shape parameter &agr;, &agr; > 1. This method is similar to other methods given by Fishman, Wallace, and Tadikamalla and is faster than these methods for &agr; > 2. The core storage requirements and the programming effort for the proposed method are similar to those of Wallace's or Tadikamalla's methods. The computational times for the proposed method remain fairly constant for medium and large values of &agr; and are superior to times obtained by Arhens and Dieter's method for all values of &agr;. The proposed method is simpler than Ahrens and Dieter's method.
A real world object modeling method for creating simulation environment of real-time systems
Authors: Ji Y. Lee, Hye J. Kim, Kyo C. Kang
Venue: Proceedings of the 15th ACM SIGPLAN conference on Object-oriented programming, systems, languages, and applications (2000)

Most real-time embedded control software feature complex interactions with asynchronous inputs and environment objects, and a meaningful simulation of a real-time control software specification requires realistic simulation of its environment. Two problems that need to be addressed in the simulation of a target software system and its environment: First, integration and simulation of the specifications of a target software system and its artificial environment are often performed too late in the lifecycle to provide any significant value. Second, real world objects in the environment usually have spatial characteristics (form) such as shape, motion, etc. that must be specified for simulation, and there is no method to express these spatial characteristics at various levels of abstraction that are adequate for the required simulation fidelity.To address these problems, we have developed a method that supports incremental specification and simulation of both the target software system and its environmental objects. The method includes: (1) a specification method for behavior, function, and form integrated objects; (2) form specification primitives that abstract common spatial characteristics of real world objects, their typical spatial relations, and spatial interactions; and (3) a methodology that refines, verifies, and validates behavior, function, and form specification of both the real-time embedded control software and its environment in a systematic and incremental manner. The proposed specification, verification, and validation method has been applied to a robot control system example to demonstrate its effectiveness and usefulness.
Minimal Fault Diameter for Highly Resilient Product Networks
Authors: Khaled Day, Abdel-Elah Al-Ayyoub
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

We present a number of results related to the fault tolerance of Cartesian product networks. We start by presenting a method for building containers (i.e., sets of node-disjoint paths) between any two nodes of a product network based on given containers for the factor networks. Then, we show that the best achievable fault diameter (i.e., diameter under maximum fault conditions), under reasonable network regularity and connectivity conditions, is equal to the fault-free diameter plus one. The concept of high fault resilience is then defined. We then prove that if each factor network is highly resilient, then their Cartesian product has minimal fault diameter. We derive from these results that Cartesian products of several popular networks are highly resilient and have minimal fault diameter equal to diameter plus one. These results spare future efforts that would be needed to individually determine the fault diameter of such networks as has been the practice with previously studied networks.
Model checking Java programs
Authors: David Dill
Venue: Proceedings of the third workshop on Formal methods in software practice (2000)

Automatic state exploration tools (model checkers) have had some success when applied to protocols and hardware designs, but there are fewer success stories about software. This is unfortunate, since the software problem is worsening even faster than the hardware and protocol problems. Model checking of concurrent programs is especially interesting, because they are notoriously difficult to test, analyze, and debug by other methods. This talk will be a description of our initial efforts to check Java programs using a model checker. The model checker supports dynamic allocation, thread creation, and recursive procedures (features that are not necessary for hardware verification), and has some special optimizations and checks tailored to multi-threaded Java program. I will also discuss some of the challenges for future efforts in this area.
Improved crosstalk modeling for noise constrained interconnect optimization
Authors: Jason Cong, David Zhigang Pan, Prasanna V. Srinivas
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

This paper presents a much improved, highly accurate yet efficient crosstalk noise model, the 2-pie model, and applies it to noise-constrained interconnect optimizations. Compared with previous crosstalk noise models of similar complexity, our 2-pie model takes into consideration many key parameters, such as coupling locations (near-driver or near-receiver), and the coarse distributed RC characteristics for victim net. Thus, it is very accurate (less than 6% error on average compared with HSPICE simulations). Moreover, our model provides simple closed-form expressions for both peak noise amplitude and noise width, so it is very useful for noise-aware layout optimizations. In particular, we demonstrate its effectiveness in two applications: (i) Optimization rule generation for noise reduction using various interconnect optimization techniques; (ii) Simultaneous wire spacing to multiple nets for noise constrained interconnect minimization.
Computer graphic standards
Authors: Jon Meads
Venue: ACM SIGGRAPH Computer Graphics (1986)

SIGGRAPH has a long history of involvement with standards. But since the great Core vs. GKS debate, there has been little reported on computer graphics standards activities in Computer Graphics, even though SIGGRAPH has been an active member of X3's Technical Committee on Computer Graphics (X3113).As SIGGRAPH's new principal representative to X3H3, I have agreed to provide an article for each issue of Computer Graphics, with the exception ofthe issue containing the SIGGRAPH conference proceedings. These articles are intended to be both informative and provocative. I'll try to keep you informed of the developments going on in regard to computer graphics standards, explain the rationale offered for various decisions and will provide opinions, mine and others.In addition, I will be glad to respond to questions, concerns and comments from you. Please send correspondence to Jon Meads, Jon Meads amp; Associates, 2516 N E 19th Avenue, Portland, OR 97212.
A tree convolution algorithm for the solution of queueing networks
Authors: Simon S. Lam, Y. Luke Lien
Venue: Communications of the ACM (1983)

A new algorithm called the tree convolution algorithm, for the computation of normalization constants and performance measures of product-form queueing networks, is presented. Compared to existing algorithms, the algorithm is very efficient in the solution of networks with many service centers and many sparse routing chains. (A network is said to have sparse routing chains if the chains visit, on the average, only a small fraction of all centers in the network.) In such a network, substantial time and space savings can be achieved by exploiting the network's routing information. The time and space reductions are made possible by two features of the algorithm: (1) the sequence of array convolutions to compute a normalization constant is determined according to the traversal of a tree; (2) the convolutions are performed between arrays that are smaller than arrays used by existing algorithms. The routing information of a given network is used to configure the tree to reduce the algorithm's time and space requirements; some effective heuristics for optimization are described. An exact solution of a communication network model with 64 queues and 32 routing chains is illustrated.
A Formal System for Reasoning about Programs Accessing a Relational Database
Authors: Marco R. Casanova, Phillip A. Bernstein
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1980)

A formal system for proving properties of programs accessing a database is introduced. Proving that a program preserves consistency of the database is one of the possible applications of the system. The formal system is a variant of dynamic logic and incorporates a data definition language (DDL) for describing relational databases and a data manipulation language (DML) whose programs access data in a database. The DDL is a many-sorted first-order language that accounts for data aggregations. The DML features a many-sorted assignment in place of the usual data manipulation statements, in addition to the normal programming language constructs.
A number system for the permutations
Authors: David Pager
Venue: Communications of the ACM (1970)

A number system described here is particularly suitable for numbering the permutations. An algorithm is then presented by which the permutation associated with a number of this kind may be obtained. Since arithmetical operations, such as the addition of 1, are easily performed in the number system, one may make use of the algorithm to generate the permutations one at a time, using a minimal amount of work space. Employed for this purpose, it provides an alternative to the method given in [1].
Augmented reality: dangerous liaisons or the best of both worlds?
Authors: Wendy E. Mackay
Venue: Proceedings of DARE 2000 on Designing augmented reality environments (2000)

In this paper, we consider the new and evocative work on tangible interfaces and the issues this raises in the light of some old lessons of HCI. In doing so, we make the point that many of these lessons of good design still apply, even when we are considering radically novel forms of interface.
Notes on the constructions of rational approximations for the eerror function and for similar functions
Authors: W. W. Clendenin
Venue: Communications of the ACM (1961)

This note describes a rational approximation for the error function which has been found useful in a subroutine as an asymptotic expression of improved accuracy. While the method of the approximation is along well-established lines [1, 2, 3, 4] a brief description may be of interest since the feasibility of a simplified means of determining the basic coefficients is shown for the error function, and this technique may be useful in other cases.
Synthesis of four-phase asynchronous control circuits from pipeline dependency graphs
Authors: Hiroto Kagotani, Takuji Okamoto, Takashi Nanya
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

We propose a method of synthesizing pipeline controllers as four-phase asynchronous circuits from specifications described as two-phase dependency graphs. Pipeline two-phase dependency graphs are transformed into four-phase ones by applying a transformation rule to each simple loop in the graphs. Four-phase dependency graphs are easily mapped onto four-phase asynchronous control circuits. We also discuss some simplification of four-phase dependency graphs.
Exact Analysis of Exact Change: The k-Payment Problem
Authors: Boaz Patt-Shamir, Yiannis Tsiounis, Yair Frankel
Venue: SIAM Journal on Discrete Mathematics (2000)

We introduce the k-payment problem: given a total budget of N units, the problem is to represent this budget as a set of coins, so that any k exact payments of total value at most N can be made using k disjoint subsets of the coins. The goal is to minimize the number of coins for any given N and k, while allowing the actual payments to be made on-line, namely without the need to know all payment requests in advance. The problem is motivated by the electronic cash model, where each coin is a long bit sequence, and typical electronic wallets have only limited storage capacity. The k-payment problem has additional applications in other resource-sharing scenarios.Our results include a complete characterization of the k-payment problem as follows. First, we prove a necessary and sufficient condition for a given set of coins to solve the problem. Using this characterization, we prove that the number of coins in any solution to the k-payment problem is at least k HN/k, where Hn denotes the nth element in the harmonic series. This condition can also be used to efficiently determine k (the maximal number of exact payments) which a given set of coins allows in the worst case. Secondly, we give an algorithm which produces, for any N and k, a solution with a minimal number of coins. In the case that all denominations are available, the algorithm finds a coin allocation with at most (k+1)HN/(k+1) coins. (Both upper and lower bounds are the best possible.) Finally, we show how to generalize the algorithm to the case where some of the denominations are not available.
Technical correspondence
Authors: Diane Crawford
Venue: Communications of the ACM (1991)

The column, &ldquo;Benchmarks for LAN Performance Evaluation,&rdquo; by Larry Press (Aug. 1988, pp. 1014-1017) presented a technique for quickly benchmarking the performance of LANs in an office environment. This piqued our interest since office automation is growing in importance. As a result, an empirical analysis of the Press benchmark programs was conducted. The results indicated that these benchmarking programs were appropriate for the benchmarking of LANs in an office environment.
A generalized method for generating argument/function values
Authors: William J. Wilson
Venue: Communications of the ACM (1970)

For any finite set of argument/function pairs, an algorithm can be automatically constructed which, on presentation of any argument, will generate its proper function value. Arguments are necessarily unique although functions may be duplicated; i.e. a many-to-one relationship is permitted. For purposes of illustration here, function and argument values are each assumed to occupy a single computer word.
ARIMA time series modeling and forecasting for adaptive I/O prefetching
Authors: Nancy Tran, Daniel A. Reed
Venue: Proceedings of the 15th international conference on Supercomputing (2001)

Bursty application I/O patterns, together with transfer limited storage devices, combine to create a major I/O bottleneck on parallel systems. This paper explores the use of time series models to forecast application I/O request times, then prefetching I/O requests during computation intervals to hide I/O latency. Experimental results with I/O intensive scientific codes show performance improvements compared to standard UNIX prefetching strategies.
On the security of multiple encryption
Authors: Ralph C. Merkle, Martin E. Hellman
Venue: Communications of the ACM (1981)

Double encryption has been suggested to strengthen the Federal Data Encryption Standard (DES). A recent proposal suggests that using two 56-bit keys but enciphering 3 times (encrypt with a first key, decrypt with a second key, then encrypt with the first key again) increases security over simple double encryption. This paper shows that although either technique significantly improves security over single encryption, the new technique does not significantly increase security over simple double encryption. Cryptanalysis of the 112-bit key requires about 256 operations and words of memory, using a chosen plaintext attack. While DES is used as an example, the technique is applicable to any similar cipher.
Faster retrieval from context trees
Authors: Ben Wegbreit
Venue: Communications of the ACM (1976)

Context trees provide a convenient way of storing data which is to be viewed as a hierarchy of contexts. This note presents an algorithm which improves on previous context tree retrieval algorithms. It is based on the observation that in typical uses context changes are infrequent relative to retrievals, so that data can be cached to speed up retrieval. A retrieval is started from the position of the previous retrieval and auxiliary structures are built up to make the search rapid. Algorithms for addition and deletion of data and for garbage collection are outlined.