ppxscal/embedding_network huggingface dataset:
Konrad Zuse: reflections on the 80th birthday of the German computing pioneer
Authors: Wolfgang K. Giloi
Venue: ACM SIGNUM Newsletter (1998)

Relatively little known outside of Germany, Konrad Zuse realized the first functioning computer in 1941 and also developed with his so-called Plankalk uuml;l in 1943-1945 the first high-level programming language, However, his inventions were overshadowed by World War II, and his work was overtaken in the public mind by the works of Aiken and von Neumann. This essay, a shortened and revised version of a eulogy by the author in December 1996 at the celebration of Zuse's 80th birthday at his former alma mater, the Technical University of Berlin, gives an overview of Zuse's work and puts his contributions in context.
Evaluating Dynamic Failure Probability for Streams with (m, k)-Firm Deadlines
Authors: Moncef Hamdaoui, Parameswaran Ramanathan
Venue: IEEE Transactions on Computers (1997)

A real-time stream is said to have (m, k)-firm deadlines if at least m out of any k consecutive customers from the stream must meet their respective deadlines. Such a stream is said to have encountered a dynamic failure if fewer than m out of any k consecutive customers meet their deadlines. Hamdaoui and Ramanathan recently proposed a scheduling policy called Distance Based Priority (DBP) in which customers are serviced with a higher priority if their streams are closer to a dynamic failure. In terms of reducing the probability of dynamic failure, Hamdaoui and Ramanathan also showed, using simulation, that the DBP policy is better than a policy in which all customers are serviced at the same priority level.In this paper, an analytic model is developed for computing the probability of dynamic failure of a real-time stream for the DBP and the single priority schemes. This model is useful for providing statistical quality of service guarantees to real-time streams. The probability of dynamic failure computed using this model is compared to the results from a discrete-event simulator. The comparison shows that the model is accurate for low and moderate loads.
Asymptotic Expansion of the Free-space Green's Function for the Discrete 3-D Poisson Equation
Authors: Richard H. Burkhart
Venue: SIAM Journal on Scientific Computing (1997)

The question of the definition, existence, and uniqueness of the free-space Green's function for the discrete 3-D Poisson equation on a general Cartesian grid is answered by presenting three alternative definitions and demonstrating their equivalence. This is a nice application of the theory of multidimensional Fourier series. Then two methods, an integral method and a Taylor series method, are presented for deriving the asymptotic expansion of the Green's function, including explicit computational formulas for several higher-order terms. Code based on these formulas is used in the Boeing transonic full potential program TRANAIR to implement a highly accurate and computationally efficient far-field (absorbing) boundary condition.
Algorithms for coupled domain MEMS simulation
Authors: N. Aluru, J. White
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

The performance of micro-electro-mechanical systemsdepends on the interaction between electrical, mechanical,and fluidic forces. Simulating this coupled problem is made moredifficult by the fact that most MEMS devices are innately three-dimensionaland geometrically complicated. It is possible to simulateefficiently these devices using domain-specific solvers, providedthe coupling betweendomains can be handled effectively. Inthis paper we will survey recent developments in coupled-domainsimulation, and give computational comparisons between relaxation,multi-level Newton, and Newton-Iterative methods for 3-Delectromechanical analysis.
High resolution time-frequency analysis of otoacoustic emissions
Authors: K. J. Blinowska, P. J. Durka, F. Grandori, G. Tognola, A. Skierski
Venue: Technology and Health Care (1997)

High resolution time-frequency analysis of OAE signals evoked by stimuli of different strength was performed by means of the Matching Pursuit algorithm. The method relies on adaptive decomposition of a signal into waveforms of well-defined frequency and time localization. Energy of OAE as a function of time and frequency was evaluated for stimuli strength of 35-80 dB SPL. Dynamic characteristics of the signal were constructed. For strong stimuli decrease of the power of high frequency components was found. Matching Pursuit proved to be a method which offers high resolution parametrisation of OAE in time-frequency space and provides excellent possibilities of investigation of the signal generation mechanisms.
Association rules over interval data
Authors: R. J. Miller, Y. Yang
Venue: ACM SIGMOD Record (1997)

We consider the problem of mining association rules over interval data (that is, ordered data for which the separation between data points has meaning). We show that the measures of what rules are most important (also called rule interest) that are used for mining nominal and ordinal data do not capture the semantics of interval data. In the presence of interval data, support and confidence are no longer intuitive measures of the interest of a rule. We propose a new definition of interest for association rules that takes into account the semantics of interval data. We developed an algorithm for mining association rules under the new definition and overview our experience using the algorithm on large real-life datasets.
A pedagogical pattern for bringing service into the curriculum via the web
Authors: Carl Erickson, Paul Leidig
Venue: Proceedings of the 2nd conference on Integrating technology into computer science education (1997)

The Web reduces the economic hurdles of publishing a message to a large audience. This paper documents a pedagogical pattern to integrate community service with the curriculum. Students in two different computer science courses teamed up to create websites for local non profit organizations (NPOs). The projects provided CS majors with real customers, the challenge of working on an interdisciplinary team, an opportunity for community service, and an opportunity to learn very new technologies. For their part the NPOs gained a new means of communicating their missions to the world. We believe the potential for reuse of this pattern is high and could benefit other schools and communities.
The Racing Algorithm: Model Selection for Lazy Learners
Authors: Oden Maron, Andrew W. Moore
Venue: Artificial Intelligence Review (1997)

Given a set of models and some training data, we would like to find the model that best describes the data. Finding the model with the lowest generalization error is a computationally expensive process, especially if the number of testing points is high or if the number of models is large. Optimization techniques such as hill climbing or genetic algorithms are helpful but can end up with a model that is arbitrarily worse than the best one or cannot be used because there is no distance metric on the space of discrete models. In this paper we develop a technique called &rsquo;&rsquo;racing&lsquo;&lsquo; that tests the set of models in parallel, quickly discards those models that are clearly inferior and concentrates the computational effort on differentiating among the better models. Racing is especially suitable for selecting among lazy learners since training requires negligible expense, and incremental testing using leave-one-out cross validation is efficient. We use racing to select among various lazy learning algorithms and to find relevant features in applications ranging from robot juggling to lesion detection in MRI scans.
On the Fault Tolerance of Some Popular Bounded-Degree Networks
Authors: F. Thomson Leighton, Bruce M. Maggs, Ramesh K. Sitaraman
Venue: SIAM Journal on Computing (1998)

In this paper, we analyze the fault tolerance of several bounded-degree networks that are commonly used for parallel computation. Among other things, we show that an N-node butterfly network containing $N^{1-\epsilon}$ worst-case faults (for any constant $\epsilon > 0$) can emulate a fault-free butterfly of the same size with only constant slowdown. The same result is proved for the shuffle-exchange network. Hence, these networks become the first connected bounded-degree networks known to be able to sustain more than a constant number of worst-case faults without suffering more than a constant-factor slowdown in performance. We also show that an N-node butterfly whose nodes fail with some constant probability p can emulate a fault-free network of the same type and size with a slowdown of 2O(log* N). These emulation schemes combine the technique of redundant computation with new algorithms for routing packets around faults in hypercubic networks. We also present techniques for tolerating faults that do not rely on redundant computation. These techniques tolerate fewer faults but are more widely applicable because they can be used with other networks such as binary trees and meshes of trees.
Buffer sharing in video-on-demand servers
Authors: Weifeng Shi, Shahram Ghandeharizadeh
Venue: ACM SIGMETRICS Performance Evaluation Review (1997)

This paper describes a buffer sharing technique that strikes a balance between the use of disk bandwidth and memory in order to maximize the performance of a video-on-demand server. We make the key observation that the configuration parameters of the system should be independent of the physical characteristics of the data (e.g., popularity of a clip). Instead, the configuration parameters are fixed and our strategy adjusts itself dynamically at run-time to support a pattern of access to the video clips.
Performance modeling of the IDES framework
Authors: David M. Nicol, Michael M. Johnson, Ann S. Yoshimura, Michael E. Goldsby
Venue: Proceedings of the eleventh workshop on Parallel and distributed simulation (1997)

The IDES project at Sandia National Laboratories is developing a large scale portable parallel simulator for use in stockpile stewardship. IDES will use the Breathing-Time-Buckets synchronization protocol; to support IDES development, this paper studies a performance model and describes performance experiments on expected work load and architectural parameters. A new parallel algorithm for terminating the window quickly is also described and analyzed.
A trace-based approach for modeling wireless channel behavior
Authors: Giao T. Nguyen, Randy H. Katz, Brian Noble, Mahadev Satyanarayanan
Venue: Proceedings of the 28th conference on Winter simulation (1996)

The loss behavior of wireless networks has become the focus of many recent research efforts. Although it is generally agreed that wireless communications experience higher error rates than wireline, the nature of these lossy links is not fully understood. This paper describes an effort to characterize the loss behavior of the AT&T WaveLAN, a popular in-building wireless interface. Using a trace-based approach, packet loss information is recorded, analyzed, and validated. Our results indicate that WaveLAN experiences an average packet error rate of 2 to 3 percent. Further analysis reveals that these errors are not independent, making it hard to model them with a simple two-state Markov chain. We derive another model based on the distributions of the error and error-free length of the packet streams. For validation, we modulate both the error models and the traces in a simulator. Trace-driven simulations yield an average TCP throughput of about 5 percent less than simulations using our best error model.
A Chernoff Bound for Random Walks on Expander Graphs
Authors: David Gillman
Venue: SIAM Journal on Computing (1998)

We consider a finite random walk on a weighted graph G; we show that the fraction of time spent in a set of vertices A converges to the stationary probability $\pi (A)$ with error probability exponentially small in the length of the random walk and the square of the size of the deviation from $\pi (A)$. The exponential bound is in terms of the expansion of G and improves previous results of [D. Aldous, Probab. Engrg. Inform. Sci., 1 (1987), pp. 33--46], [L. Lovász and M. Simonovits, {\it Random Structures Algorithms}, 4 (1993), pp. 359--412], [M. Ajtai, J. Komlós, and E. Szemerédi, Deterministic simulation of logspace, in Proc. 19th ACM Symp. on Theory of Computing, 1987].We show that taking the sample average from one trajectory gives a more efficient estimate of $\pi (A)$ than the standard method of generating independent sample points from several trajectories. Using this more efficient sampling method, we improve the algorithms of Jerrum and Sinclair for approximating the number of perfect matchings in a dense graph and for approximating the partition function of a ferromagnetic Ising system, and we give an efficient algorithm to estimate the entropy of a random walk on an unweighted graph.
Parallel logic simulation on general purpose machines
Authors: Larry Soulé, Tom Blank
Venue: Proceedings of the 25th ACM/IEEE Design Automation Conference (1988)

Three parallel algorithms for logic simulation have been developed and implemented on a general purpose shared-memory parallel machine. The first algorithm is a synchronous version of a traditional event-driven algorithm which achieves speed-ups of 6 to 9 with 15 processors. The second algorithm is a synchronous unit-delay compiled mode algorithm which achieves speed-ups of 10 to 13 with 15 processors. The third algorithm is totally asynchronous with no synchronization locks or barriers between processors and the problems of massive state storage and deadlock that are traditionally associated with asynchronous simulation have been eliminated. The processors work independently at their own speed on different elements and at different times. When simulating circuits with little or no feedback, the asynchronous simulation technique varies between 1 to 3 times faster than the conventional event-driven algorithm using 1 processor and depending on the circuit, achieves 10 to 20% better utilization using 15 processors.
A Formal Verification Environment for Railway Signaling System Design
Authors: Cinzia Bernardeschi, Alessandro Fantechi, Stefania Gnesi, Salvatore Larosa, Giorgio Mongardi, Dario Romano
Venue: Formal Methods in System Design (1998)

A fundamental problem in the design and development of embedded control systems is the verification of safety requirements. Formal methods, offering a mathematical way to specify and analyze the behavior of a system, together with the related support tools can successfully be applied in the formal proof that a system is safe. However, the complexity of real systems is such that automated tools often fail to formally validate such systems.This paper outlines an experience on formal specification and verification carried out in a pilot project aiming at the validation of a railway computer based interlocking system. Both the specification and the verification phases were carried out in the JACK (Just Another Concurrency Kit) integrated environment. The formal specification of the system was done by means of process algebra terms. The formal verification of the safety requirements was done first by giving a logical specification of such safety requirements, and then by means of model checking algorithms. Abstraction techniques were defined to make the problem of safety requirements validation tractable by the JACK environment.
Generation of synthetic sequential benchmark circuits
Authors: Michael Hutton, Jonathan Rose, Derek Corneil
Venue: Proceedings of the 1997 ACM fifth international symposium on Field-programmable gate arrays (1997)

Programmable logic architectures increase in capacity before commercial circuits are designed for them, yielding a distinct problem for FPGA vendors: how to test and evaluate the effectiveness of new architectures and software. Benchmark circuits arc a precious commodity, and often cannot be found at the correct granularity, or in the desired quantity. In previous work, we have defined important physical characteristics of combinational circuits. We presented a tool (CIRC) to extract them, and gaue an algorithm and tool (GEN) which generates random circuits, parameterized by those characteristics or by a realistic set of defaults. Though a promising step, only a small portion of real circuits are fully combinational. In this paper we extend the effort to model sequential circuits. We propose new characteristics and generate circuits which are sequential. This allows for the generation of truly useful benchmark circuits, both at and beyond the sizes of next-generation FPGAs. By comparing the post-lay out properties of the generated circuits with already existing circuits, we demonstrate that the synthetic circuits are much more realistic than random graphs with the same number of nodes, edges and I/Os.
Delay Test Generation: A Hardware Perspective
Authors: Jacob Savir
Venue: Journal of Electronic Testing: Theory and Applications (1997)

An important problem one faces during design of a built-in self-test (BIST) based delay test is the selection of a proper generator to apply the test vectors. This problem is due to the need of applying a pair of patterns to detect any given delay fault. The second vector has to be launched against the logic immediately following the first vector. This timing requirement places severe restrictions on the kind of hardware suitable for the task, especially in built-in self-test applications where the generator must reside on chip.This paper studies the various options one has in designing the delay test vector generator. Both scan and non-scan designs are addressed. The different options are measured based on their performance, cost, and flexibility.
Improving a multistage/multiprocessor flow-shop problem of numerous technological constraints through scheduling
Authors: Way Kuo, Jon Yanney, Russell Tsai
Venue: Proceedings of the 17th conference on Winter simulation (1985)

The manufacturing of industrial rubber compounds is a three-stage process on a Banbury production system. At each stage the rubber is mixed (in a Banbury mixer) and transferred to next-stage storage. Depending on requirements, the first two stages may be repeated up to three times. Finally, rubber is mixed on the third stage and then milled to obtain a slab form of the new compound rubber. The objective is to derive a &ldquo;good&rdquo; heuristic scheduling algorithm that uses a series of sorts, searches, and simulations in order to sequence and route jobs through production stages. Evaluation criteria are based on the increase in equipment utilization and on satisfying quality and operating restrictions. Schedule feasibility will be tested by a GPSS simulation model of the production system.
The Structure and Number of Obstructions to Treewidth
Authors: Siddharthan Ramachandramurthi
Venue: SIAM Journal on Discrete Mathematics (1997)

For each pair of nonadjacent vertices in a graph, consider the greater of the degrees of the two vertices. The minimum of these maxima is a lower bound on the treewidth of a graph, unless it is a complete graph. This bound has three consequences. First, the obstructions of order w+3 for treewidth w have a simple structural characterization. Second, these graphs are exactly the pathwidth obstructions of order w+3. Finally, although there is only one obstruction of order w+2 for width w, the number of obstructions of order w+3 is bounded below by an exponential function of $\sqrt w$.
rdp&mdash;an iterator-based recursive descent parser generator with tree promotion operators
Authors: Adrian Johnstone, Elizabeth Scott
Venue: ACM SIGPLAN Notices (1998)

rdp is a parser generator which accepts Iterator Backus Naur Form productions decorated with attributes and ANSI-C actions and produces recursive descent parsers. It has special support for the generation of tree-based intermediate forms, built-in symbol table handling for the implementation of context-sensitive components of the language syntax and a support library that includes a generalised graph handling module that can output graphs in a form suitable for use with well known visualisation tools.
Constructing Levels in Arrangements and Higher Order Voronoi Diagrams
Authors: Pankaj K. Agarwal, Mark de Berg, Jirí Matousek, Otfried Schwarzkopf
Venue: SIAM Journal on Computing (1998)

We give simple randomized incremental algorithms for computing the Amk-level in an arrangement of n lines in the plane or in an arrangement of n planes in $\Reals^3$. The expected running time of our algorithms is $O(nk+n\alpha(n)\log n)$ for the planar case and O(nk2 + n log3 n) for the three-dimensional case. Both bounds are optimal unless k is very small. The algorithm generalizes to computing the Amk-level in an arrangement of discs or x-monotone Jordan curves in the plane. Our approach can also compute the k-level; this yields a randomized algorithm for computing the order-k Voronoi diagram of n points in the plane in expected time O(k(n-k)log n + n log3 n).
Experimental designs in computer simulation
Authors: Ardavan Nozari
Venue: Proceedings of the 17th conference on Winter simulation (1985)

Experimental designs are often used in computer simulation studies. Classical statistical analysis of experimental designs requires variances to be equal. However, in simulation studies this assumption is often violated. The classical way of dealing with unequal variances is application of variance stabilizing transformations. An applied treatment of these transformations may be found in Neter and Wasserman [1]. Application of transformations will make the results of the analysis in terms of the transformed data. Therefore, they are recommended when either the results can be transformed back to the original domain, or the interpretation of results from the transformed data is as sensible as from the original data. Several authors, including Fishman [2], argue that transformations result in finding &ldquo;the natural scale of data analysis&rdquo;, because the &ldquo;right&rdquo; transformation will often reduce the complexity of the model. However, there are situations in which one is only interested in the parameters of the original data, and inferences based on the transformed data are either not suitable or can not be transformed back to the original domain. In this talk, we outline an approximation method based on the original data for dealing with unequal variances in application of experimental designs. We refer to this method as &ldquo;OLS with Sample Variances.&rdquo; The basic idea behind the method is to incorporate the ordinary least square estimator with the sample variances. Our goal in this talk is to emphasize the practical application of the method. Nozari [3] considers incorporating a number of different estimators of the unequal variances with both the ordinary least squares and generalized least squares. Also, a Monte Carlo study is presented in that paper to examine the behavior of these incorporations. It is concluded that &ldquo;OLS with Sample Variances&rdquo; performs quite satisfactorily and is better than others.