ppxscal/embedding_network huggingface dataset:
Combinatorial Properties and Constructions of Traceability Schemes and Frameproof Codes
Authors: D. R. Stinson, R. Wei
Venue: SIAM Journal on Discrete Mathematics (1998)

In this paper, we investigate combinatorial properties and constructions of two recent topics of cryptographic interest, namely frameproof codes for digital fingerprinting and traceability schemes for broadcast encryption. We first give combinatorial descriptions of these two objects in terms of set systems and also discuss the Hamming distance of frameproof codes when viewed as error-correcting codes. From these descriptions, it is seen that existence of a c-traceability scheme implies the existence of a c-frameproof code. We then give several constructions of frameproof codes and traceability schemes by using combinatorial structures such as t-designs, packing designs, error-correcting codes, and perfect hash families. We also investigate embeddings of frameproof codes and traceability schemes, which allow a given scheme to be expanded at a later date to accommodate more users. Finally, we look briefly at bounds which establish necessary conditions for existence of these structures.
An L1--Error Bound for a Semi-Implicit Difference Scheme Applied to a Stiff System of Conservation Laws
Authors: Hans Joachim Schroll, Aslak Tveito, Ragnar Winther
Venue: SIAM Journal on Numerical Analysis (1997)

A straightforward semi-implicit finite-difference method approximating a system of conservation laws including a stiff relaxation term is analyzed. We show that the error, measured in $\Lone$, is bounded by $O(\sqrt{\dt})$ independent of the stiffness, where the time step $\dt$ represents the mesh size. As a simple corollary we obtain that solutions of the stiff system converge toward the solution of an equilibrium model at a rate of $O(\delta^{1/3})$ in $\Lone$ as the relaxation time $\delta$ tends to zero.
New Ramsey Bounds from Cyclic Graphs of Prime Order
Authors: Neil J. Calkin, Paul Erdos, Craig A. Tovey
Venue: SIAM Journal on Discrete Mathematics (1997)

We present new explicit lower bounds for some Ramsey numbers. All the graphs are cyclic and are on a prime number of vertices. We give theoretical motivation for searching for Ramsey graphs of prime order and provide additional computational evidence that primes tend to be better than composites.
A hierarchical fair service curve algorithm for link-sharing, real-time and priority services
Authors: Ion Stoica, Hui Zhang, T. S. Eugene Ng
Venue: Proceedings of the ACM SIGCOMM '97 conference on Applications, technologies, architectures, and protocols for computer communication (1997)

In this paper, we study hierarchical resource management models and algorithms that support both link-sharing and guaranteed real-time services with decoupled delay (priority) and bandwidth allocation. We extend the service curve based QoS model, which defines both delay and bandwidth requirements of a class, to include fairness, which is important for the integration of real-time and hierarchical link-sharing services. The resulting Fair Service Curve link-sharing model formalizes the goals of link-sharing and real-time services and exposes the fundamental tradeoffs between these goals. In particular, with decoupled delay and band-width allocation, it is impossible to simultaneously provide guaranteed real-time service and achieve perfect link-sharing. We propose a novel scheduling algorithm called Hierarchical Fair Service Curve (H-FSC) that approximates the model closely and efficiently. The algorithm always guarantees the performance for leaf classes, thus ensures real-time services, while minimizing the discrepancy between the actual services provided to the interior classes and the services defined by the Fair Service Curve link-sharing model. We have implemented the H-FSC scheduler in the NetBSD environment. By performing simulation and measurement experiments, we evaluate the link-sharing and real-time performances of H-FSC, and determine the computation over-head.
Power macromodeling for high level power estimation
Authors: Subodh Gupta, Farid N. Najm
Venue: Proceedings of the 34th annual Design Automation Conference (1997)

A modeling approach is presentedthat captures the dependence of the power dissipationof a combinational logic circuit on its input/outputsignal switching activity.The resultingpower macromodel, consisting of a single three dimensionaltable, can be used to estimate the powerconsumed in the circuit for any given input/outputsignal statistics.Given a low-level (typically gate-level)description of the circuit, we describe a characterizationprocess by which such a table modelcan be automatically built.In contrast to otherproposed techniques, this can be done for any givenlogic circuit without any user intervention, and appliesto all possible input/output signal statistics;it does not require one to construct specialized analyticalequations for the power dissipation.Thethree dimensions of our table-based model are theaverage input signal probability, average input transitiondensity, and average output zero-delay transition density.This approach has been implemented and modelshave been built for many benchmark circuits.Overa wide range of input signal statistics, we show thatthis model gives very good accuracy, with an RMSerror of under about 6%.
Algorithms for timing requirement analysis and generation
Authors: Steven K. Sherman
Venue: Proceedings of the 25th ACM/IEEE Design Automation Conference (1988)

Timing requirement analysis removes ambiguity from specifications and generates results for use in other simulations of digital systems. It involves construction of a graph representing all constraints between state transitions and the generation of an optimized graph having a maximum number of simultaneous constraints. Optimization involves prioritizing the constraints or searching for a solution which violates no constraints.
An efficient caching support for critical sections in large-scale shared-memory multiprocessors
Authors: Sang Lyul Min, Jean-Loup Baer, Hyoung-Joo Kim
Venue: Proceedings of the 4th international conference on Supercomputing (1990)

Directory-based and software-assisted schemes are the two main approaches to solving the cache coherence problem in large scale shared-memory multiprocessors. Until now, the emphasis in software-assisted schemes has been on ascertaining consistency within parallel constructs such as DoAll or DoAcross loops. In this paper, we propose a timestamped-based approach which also allows caching within critical sections. This scheme combines the best features of software-assisted and directory-based cache coherence protocols. It is based on a compile time analysis of interactions among critical sections and execution time local detection of cache incoherence by comparing the times when a variable was last written and last updated in the cache. A quantitative evaluation based on synthetic traces shows that this scheme results in hit ratios almost as high as in directory-based solutions while significantly reducing the network traffic.
A Posteriori Error Estimators for the Stokes and Oseen Equations
Authors: Mark Ainsworth, J. Tinsley Oden
Venue: SIAM Journal on Numerical Analysis (1997)

The problem of obtaining /posteriori/ estimates of the discretization error when one uses finite element methods to approximate problems with an incompressibility constraint is discussed. A general approach to the treatment of the constraint condition and to the (possible) non-self-adjointness of the associated momentum equations is presented. A posteriori error estimates are derived for adaptive h, p, and h-p type finite element schemes. Key features are that the local error residual problems are not subject to an incompressibility constraint thereby avoiding the need for special finite element schemes and that the analysis is valid for essentially any discretization scheme, including continuous and discontinuous pressure spaces. The estimator bounds the actual error measured in an energy-like norm.
Model refinement for hardware-software codesign
Authors: Jie Gong, Daniel D. Gajski, Smita Bakshi
Venue: ACM Transactions on Design Automation of Electronic Systems (TODAES) (1997)

Hardware-software codesign, which implements a given specification with a set of system components such as ASICs and processors, includes several key tasks such as system component allocation, functional partitioning, quality metrics estimation, and model refinement. In this work, we focus on the model refinement task which transforms a specification from an original functional model to a refined implementation model. First, we categorize several commonly used implementation models and describe a set of refinement procedures to transform a specification to each of these implementation models. We also present a set of experimental results to compare the implementation models and to demonstrate how the proposed approach can be used to explore different implementation styles.
Object lessons learned from a distributed system for remote building monitoring and operation
Authors: Frank Olken, Hans-Arno Jacobsen, Chuck McParland, Mary Ann Piette, Mary F. Anderson
Venue: ACM SIGPLAN Notices (1998)

In this paper we describe our experiences with the design, the deployment, and the initial operation of a distributed system for the remote monitoring and operation of multiple heterogeneous commercial buildings across the Internet from a single control center. Such systems can significantly reduce building energy usage.Our system is distinguished by its ability to interface to multiple heterogeneous legacy building Energy Management Control Systems (EMCSs), its use of the Common Object Request Broker Architecture (CORBA) standard communication protocols for the former task, development of a standardized naming system for monitoring points in buildings, the use of a relational DBMS to store and process time series data, automatic time and unit conversion, and a scripted time series visualization system.We describe our design choices and our experiences in development and operation. We note requirements for future distributed systems software for interoperability of heterogeneous real-time data acquisition and control systems.
Sensitivity and scenario analysis for simulation metamodels
Authors: Susan M. Sanchez, L. Douglas Smith, Edward C. Lawrence
Venue: Proceedings of the 28th conference on Winter simulation (1996)

We use simple orthogonal and non-orthogonal designs to analyze a multi-tiered model for forecasting performance of a large-scale home mortgage portfolio. The experiments are used to assess the sensitivity of performance to projected changes in economic conditions as well as the sensitivity of the model to coefficients estimated from historical data. Our results attribute the variation in loan performance to variation in individual factors or factor combinations, indicating which are crucial to monitor or forecast accurately. The results are at times counter-intuitive, indicating the benefits of a systematic approach to sensitivity assessment and scenario generation.
A channelless, multilayer router
Authors: R. Eric Lunow
Venue: Proceedings of the 25th ACM/IEEE Design Automation Conference (1988)

We have implemented a channel-less, gridless, multilayer router as part of the Magic IC layout system. The router is designed to handle new routing problems associated with emerging technologies such as Wafer Scale Integration and multilayered metal processes. Three features distinguish this router: rectilinear Steiner trees with floating segments, a routing scheduler, and a corner-stitched database.
MEDCAT: an APL program for medical diagnosis, consultation, and teaching
Authors: W. D. Hagamen, Martin Gardy, Gregory Bell, Edwin Rekosh, Steven Zatz
Venue: ACM SIGAPL APL Quote Quad (1985)

This is a description of MEDCAT, a computer program which makes diagnoses, explains each step in its reasoning in response to questions, increases its knowledge and reasoning ability by conversing with expert physicians, and uses its logical and communicative skills to help and evaluate medical students in the proper approach to medical diagnosis. The mechanism for each of these features is discussed. MEDCAT is coded in APL and implemented on a 68000 based microcomputer.
A New Parallel Algorithm for Time-Slot Assignment in Hierarchical Switching Systems
Authors: Suresh Chalasani
Venue: IEEE Transactions on Computers (1997)

The time-slot assignment (TSA) problem in a TDM switching system is to find a conflict-free assignment of traffic-units to slots such that the frame-length is minimized. In this paper, we develop a new parallel algorithm for the TSA problem in hierarchical switching systems (HSS). To design the parallel algorithm, we first reduce the TSA problem to the problem of routing permutations in three-stage Clos networks; we also show how this reduction can be achieved in polylogarithmic time using a polynomial number of processors on the EREW PRAM model. Once this reduction is achieved, we use existing parallel algorithms in literature to route permutations in Clos networks. The overall time-complexity of our parallel algorithm is O(log3X) using O(MX) processors, where X = max{M, L}, M is the number of inputs of the HSS, and L is the length of the time-slot assignment. This result is a significant improvement upon the earlier parallel algorithms, which require O(M2 log M log L) time and O(ML) processors to solve the TSA problem.
Performance comparison of high-level algebraic nets distributed simulation protocols
Authors: Karim Djemame, Mohamed Bettaz, Dennis C. Gilles, Lewis M. Mackenzie
Venue: Proceedings of the 28th conference on Winter simulation (1996)

This paper addresses the problem of developing distributed simulation techniques to analyze ECATNets. ECATNets (Extended Concurrent Algebraic Term Nets) are a kind of High-Level Algebraic Nets used for specifying various aspects of distributed and parallel systems. Their most distinctive feature is that their semantics is defined in terms of rewriting logic. The conservative and optimistic approaches of Distributed Discrete Event Simulation (DDES) are used as the starting point to discuss a simulation framework for studying the behaviour of ECATNet models. The ECAT Net model to be simulated is partitioned into several connected subnets. The various subnets are simulated in parallel by several Logical Processes. Next we develop two distributed simulation protocols to execute discrete-event simulations of ECATNets.
Parallel Algorithms for the Spectral Transform Method
Authors: Ian T. Foster, Patrick H. Worley
Venue: SIAM Journal on Scientific Computing (1997)

The spectral transform method is a standard numerical technique for solving partial differential equations on a sphere and is widely used in atmospheric circulation models. Recent research has identified several promising algorithms for implementing this method on massively parallel computers; however, no detailed comparison of the different algorithms has previously been attempted. In this paper, we describe these different parallel algorithms and report on computational experiments that we have conducted to evaluate their efficiency on parallel computers. The experiments used a testbed code that solves the nonlinear shallow water equations on a sphere; considerable care was taken to ensure that the experiments provide a fair comparison of the different algorithms and that the results are relevant to global models. We focus on hypercube- and mesh-connected multicomputers with cut-through routing, such as the Intel iPSC/860, DELTA, and Paragon, and the nCUBE/2, but we also indicate how the results extend to other parallel computer architectures. The results of this study are relevant not only to the spectral transform method but also to multidimensional fast Fourier transforms (FFTs) and other parallel transforms.
First-Order System Least Squares for Second-Order Partial Differential Equations: Part II
Authors: Zhiqiang Cai, Thomas A. Manteuffel, Stephen F. McCormick
Venue: SIAM Journal on Numerical Analysis (1997)

This paper develops a least-squares functional that arises from recasting general second-order uniformly elliptic partial differential equations in $n=2$ or $3$ dimensions as a system of first-order equations. In part I [Z. Cai, R. D. Lazarov, T. Manteuffel, and S. McCormick, SIAM J. Numer. Anal., 31 (1994), pp. 1785--1799] a similar functional was developed and shown to be elliptic in the $H(\divv) \times H^1$ norm and to yield optimal convergence for finite element subspaces of $H(\divv) \times H^1$. In this paper the functional is modified by adding a compatible constraint and imposing additional boundary conditions on the first-order system. The resulting functional is proved to be elliptic in the $(H^1)^{n+1}$ norm. This immediately implies optimal error estimates for finite element approximation by standard subspaces of $(H^1)^{n+1}$. Another direct consequence of this ellipticity is that multiplicative and additive multigrid algorithms applied to the resulting discrete functionals are optimally convergent. As an alternative to perturbation-based approaches, the least-squares approach developed here applies directly to convection--diffusion--reaction equations in a unified way and also admits a fast multigrid solver, historically a missing ingredient in least-squares methodology.
Synchronization of Locally Coupled Neural Oscillators
Authors: Valentin Dragoi, Ioan Grosu
Venue: Neural Processing Letters (1998)

A new method of controlling Fitzhugh-Nagumo (F-N) neural oscillators, Fitzhugh [1], with local coupling is presented. It is proved that through the use of an additive closed-loop controlling action that entrains each neural oscillator to a &lsquo;goal&lsquo; behavior, necessary and sufficient conditions for the occurrence of synchronization in networks of unidirectionally self-connected neural oscillators are obtained in terms of asymptotic stability. These conditions suggest that rapid global synchronization can be achieved using sufficiently strong local inhibitory connections.
CLAP: teaching data structures in a creative way
Authors: V. Meisalo, E. Sutinen, J. Tarhio
Venue: Proceedings of the 2nd conference on Integrating technology into computer science education (1997)

CLAP is a pedagogical approach for Computer Science education, applied here especially to laboratory courses. CLAP or Creative Lab with Active Participation provides an open learning environment, utilizing creative problem solving methods. For successful learning, CLAP emphasizes group processes. Pilot courses using CLAP were carried out during the Fall Semester of 1996 and the Spring Semester of 1997.
Functional reactive animation
Authors: Conal Elliott, Paul Hudak
Venue: Proceedings of the second ACM SIGPLAN international conference on Functional programming (1997)

Fran (Functional Reactive Animation) is a collection of data types and functions for composing richly interactive, multimedia animations. The key ideas in Fran are its notions of behaviors and events. Behaviors are time-varying, reactive values, while events are sets of arbitrarily complex conditions, carrying possibly rich information. Most traditional values can be treated as behaviors, and when images are thus treated, they become animations. Although these notions are captured as data types rather than a programming language, we provide them with a denotational semantics, including a proper treatment of real time, to guide reasoning and implementation. A method to effectively and efficiently perform event detection using interval analysis is also described, which relies on the partial information structure on the domain of event times. Fran has been implemented in Hugs, yielding surprisingly good performance for an interpreter-based system. Several examples are given, including the ability to describe physical phenomena involving gravity, springs, velocity, acceleration, etc. using ordinary differential equations.
PERFORM: A Fast Object Recognition Method Using Intersection of Projection Error Regions
Authors: Bharath R. Modayur, Linda G. Shapiro
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1997)

This paper describes a new formulation of the problem of object recognition under a bounded-error noise model and an object recognition methodology called PERFORM that finds matches by establishing correspondences between model and image features using this formulation. PERFORM evaluates correspondences by intersecting error regions in the image space. The algorithm is analyzed with respect to theoretical complexity as well as actual running times. When a single solution to the matching problem is sought, the time complexity of the sequential matching algorithm for 2D-2D matching using point features is of the order O(I3N2), where N is the number of model features and I is the number of image features. When line features are used, the sequential complexity is of the order O(I2N2). When a single solution is sought, PERFORM runs faster than the fastest known algorithm [8] to solve the bounded-error matching problem. The PERFORM method, which was developed with parallelizability as an important requirement, is shown to be easily realizable on both SIMD and MIMD architectures. The parallel versions of PERFORM are scalable, achieving linear speedups on both the MasPar and the KSR machines. When implemented in parallel, PERFORM does not require a large number of processors or memory, needs minimal to no inter-processor communication, requires no load balancing, and can produce all or just one solution to the matching problem. The communication-efficient version of PERFORM described in this paper has minimal memory requirements, since it only needs to store the model and image features and computes everything else on the fly.
Uncertainty and sensitivity studies of models of environmental systems
Authors: E. Marian Scott
Venue: Proceedings of the 28th conference on Winter simulation (1996)

Traditionally, sensitivity and uncertainty analyses in environmental modelling contribute quantitative descriptions of the relative importances of individual parameters and processes, highlighting areas of significant contributors to the overall uncertainties of model predictions and giving markers for areas requiring substantial improvement (perhaps through directed experimental work). Both sensitivity and uncertainty analysis require extensive re-sampling from input data and simulation of model response and there is a large and growing literature concerning their use in environmental modelling. There is however growing interest in the sensitivity of predictions to model structure, and in evaluating the contribution of model structural uncertainty to the overall uncertainty within the general framework of sensitivity analysis (Draper, 1995, Beven, 1993, Beven and Binley, 1992). Sensitivity and uncertainty analysis contribute to all stages of model development, testing and assessment and their impact on model reliability and validity will be described. After a general introduction to sensitivity and uncertainty analysis and discussion of their contributions, some applications of sensitivity analysis to several environmental modelling studies will be presented.
A tutorial on TESS: the extended simulation system
Authors: Charles R. Standridge, David K. Vaughan, Mary L. Sale
Venue: Proceedings of the 17th conference on Winter simulation (1985)

TESS, The Extended Simulation System, integrates simulation, data management and graphics capabilities to provide a framework for performing simulation projects. Capabilities for building SLAM II networks graphically, animating simulation runs without programming, and generating graphs of all simulation results are provided. Report generation and the post-run analysis of simulation results are included. Forms input for simulation run controls and user defined data are provided. The fourth generation TESS language provides a single user interface to all TESS capabilities.