ppxscal/embedding_network huggingface dataset:
IES3: a fast integral equation solver for efficient 3-dimensional extraction
Authors: Sharad Kapur, David E. Long
Venue: Proceedings of the 1997 IEEE/ACM international conference on Computer-aided design (1997)

Integral equation techniques are often used to extract models of integrated circuit structures. This extraction involves solving a dense system of linear equations, and using direct solution methods is prohibitive for large problems. In this paper, we present IES/sup 3/ (pronounced "ice cube"), a fast Integral Equation Solver for three-dimensional problems with arbitrary kernels. Extraction methods based on IES/sup 3/ are substantially more efficient than existing multipole-based approaches.
Supercomputing with transputers&mdash;past, present and future
Authors: Anthony J. G. Hey
Venue: Proceedings of the 4th international conference on Supercomputing (1990)

The paper traces the development of large multi-transputer systems for high-performance scientific and engineering computing. After defining what we mean by 'supercomputing' in the context of this paper, the past and present state of transputer supercomputing environments is illustrated by a discussion of three specific projects. These are the Esprit 'SuperNode' project or P1085, the Edinburgh Concurrent Supercomputer project and the Victor project at IBM Research in Yorktown Heights. The present parallel programming environments available for transputer systems are also briefly reviewed. The paper concludes with a look to the future. Inmos' announced plans for the next generation transputer, code-named H1, are described along with a comparison with the new Intel iWarp chip. We can classify this Intel component as a 'generic' transputer in that it integrates computing elements, memory elements and communication hardware on a single VLSI chip. Both these new components should make for a bright future for supercomputing with transputer-like building blocks.
Micro-operation perturbations in chip level fault modeling
Authors: Chien-Hung Chao, F. Gail Gray
Venue: Proceedings of the 25th ACM/IEEE Design Automation Conference (1988)

The goal of this paper is to determine the best micro-operation perturbation for modeling faults at the chip level. The measure used is the gate level stuck-at fault coverage achieved by the tests derived to cover the micro-operation perturbation faults. For small combinational circuits, it is shown that perturbing the elements into the logic dual is a good choice. For large combinational circuits, it is shown that there is very little variation in the gate level coverage achieved by the various micro-operation faults. In this case, if coverage is to be improved, the micro-operation perturbation method must be augmented by other techniques.
On tuning the microarchitecture of an HPS implementation of the VAX
Authors: James E. Wilson, Steve Melvin, Michael Shebanow, Wen-mei Hwu, Yale N. Patt
Venue: Proceedings of the 20th annual workshop on Microprogramming (1987)

The HPS Microarchitecture has been developed as an execution model for implementing various architectures at very high performance. A considerable amount of effort has gone into the use of HPS as a microarchitecture for the VAX. In this paper, we describe our first full simulation of the microVAX subset, and report the results of varying (i.e. tuning) certain important parameters.
Development of a Health Promotion System for the Elderly: Committee of Health Evaluation for Elderly Persons Council of Japan AMHTS Institutions
Authors: S. Shibata, A. Tuchiya, M. Tamura, N. Sasamori, K. Yoshida, Y. Iwai, M. Hattori, Y. Otsuka, S. Tohyama, A. Uchiyama
Venue: Journal of Medical Systems (1998)

A new health promotion approach for elderly persons is required which maintains not only their physical health but also their quality of life. We are developing a health promotion system which makes use of questionnaires dealing with physical conditions and quality of life, and makes health reports. Health evaluation is carried out in three steps. First, detailed information about the physical health of each client is collected. Second, quality of life is evaluated according to five health indicators. Last, health recommendations are generated. An artificial intelligence (AI) program produces detailed questions to collect necessary information for the evaluation of a client's health. The information related to quality of life is converted into five health indicators and presented as a radar-chart in documents and displays. The knowledge-based AI program automatically generates the health recommendation documents. This information is available for physicians and nurses for health counseling.
Visual Image Retrieval by Elastic Matching of User Sketches
Authors: Alberto Del Bimbo, Pietro Pala
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1997)

Effective image retrieval by content from database requires that visual image properties are used instead of textual labels to properly index and recover pictorial data. Retrieval by shape similarity, given a user-sketched template is particularly challenging, owing to the difficulty to derive a similarity measure that closely conforms to the common perception of similarity by humans. In this paper, we present a technique which is based on elastic matching of sketched templates over the shapes in the images to evaluate similarity ranks. The degree of matching achieved and the elastic deformation energy spent by the sketch to achieve such a match are used to derive a measure of similarity between the sketch and the images in the database and to rank images to be displayed. The elastic matching is integrated with arrangements to provide scale invariance and take into account spatial relationships between objects in multi-object queries. Examples from a prototype system are expounded with considerations about the effectiveness of the approach and comparative performance analysis.
Sufficient Optimality Conditions for Optimal Control Subject to State Constraints
Authors: K. Malanowski
Venue: SIAM Journal on Control and Optimization (1997)

Strong second-order sufficient optimality conditions (SSC) are derived for optimal control problems of systems described by nonlinear ODEs subject to mixed control-state and pure state constraints. The obtained SSC are expressed in terms of a modified Legendre--Clebsch condition and the associated Riccati equation. The role of SSC in stability analysis of solutions to parametric optimal control problems is briefly discussed.
ExpertFit: total support for simulation input modeling
Authors: Averill M. Law, Michael G. McComas
Venue: Proceedings of the 28th conference on Winter simulation (1996)

In this paper, we explain the important role of simulation input modeling in a successful simulation study. Two pitfalls in simulation input modeling are then presented and we explain how any analyst, regardless of their knowledge of statistics, can easily avoid these pitfalls through the use of ExpertFit, the Windows-based successor to the UniFit II input modeling package. We use a set of real-world system data to demonstrate how the package automatically specifies, evaluates, and ranks candidate probability distributions, and then assists an analyst in deciding whether the 'best' candidate probability distribution provides an adequate representation of the data. If no candidate probability distribution provides an adequate fit, then ExpertFit can define an empirical distribution function. In either case, the probability distribution can be automatically expressed in the analyst's simulation software. We then consider the general case of selecting a probability distribution in the absence of data. As an example, we show how ExpertFit can be used to create busy-time and downtime models for machines that are subject to random breakdowns.
Deriving Petri Nets from Finite Transition Systems
Authors: Jordi Cortadella, Michael Kishinevsky, Luciano Lavagno, Alexandre Yakovlev
Venue: IEEE Transactions on Computers (1998)

This paper presents a novel method to derive a Petri Net from any specification model that can be mapped into a state-based representation with arcs labeled with symbols from an alphabet of events (a Transition System, TS). The method is based on the theory of regions for Elementary Transition Systems (ETS). Previous work has shown that, for any ETS, there exists a Petri Net with minimum transition count (one transition for each label) with a reachability graph isomorphic to the original Transition System. Our method extends and implements that theory by using the following three mechanisms that provide a framework for synthesis of safe Petri Nets from arbitrary TSs. First, the requirement of isomorphism is relaxed to bisimulation of TSs, thus extending the class of synthesizable TSs to a new class called Excitation-Closed Transition Systems (ECTS). Second, for the first time, we propose a method of PN synthesis for an arbitrary TS based on mapping a TS event into a set of transition labels in a PN. Third, the notion of irredundant region set is exploited, to minimize the number of places in the net without affecting its behavior. The synthesis method can derive different classes of place-irredundant Petri Nets (e.g., pure, free choice, unique choice) from the same TS, depending on the constraints imposed on the synthesis algorithm. This method has been implemented and applied in different frameworks. The results obtained from the experiments have demonstrated the wide applicability of the method.
Empirical studies of competitve spinning for a shared-memory multiprocessor
Authors: Anna R. Karlin, Kai Li, Mark S. Manasse, Susan Owicki
Venue: ACM SIGOPS Operating Systems Review (1991)

A common operation in multiprocessor programs is acquiring a lock to protect access to shared data. Typically, the requesting thread is blocked if the lock it needs is held by another thread. The cost of blocking one thread and activating another can be a substantial part of program execution time. Alternatively, the thread could spin until the lock is free, or spin for a while and then block. This may avoid context-switch overhead, but processor cycles may be wasted in unproductive spinning. This paper studies seven strategies for determining whether and how long to spin before blocking. Of particular interest are competitive strategies, for which the performance can be shown to be no worse than some constant factor times an optimal off-line strategy. The performance of five competitive strategies is compared with that of always blocking, always spinning, or using the optimal off-line algorithm. Measurements of lock-waiting time distributions for five parallel programs were used to compare the cost of synchronization under all the strategies. Additional measurements of elapsed time for some of the programs and strategies allowed assessment of the impact of synchronization strategy on overall program performance. Both types of measurements indicate that the standard blocking strategy performs poorly compared to mixed strategies. Among the mixed strategies studied, adaptive algorithms perform better than non-adaptive ones.
Analysis of the Cell-Vertex Finite Volume Method for Hyperbolic Problems with Variable Coefficients
Authors: Philippe Balland, Endre Süli
Venue: SIAM Journal on Numerical Analysis (1997)

An analysis of the cell-vertex finite volume method is presented for a scalar linear hyperbolic equation with variable coefficients. The cell-vertex approximation is shown to be second-order convergent in the L2-norm and first-order convergent in the H1-norm, provided the exact solution belongs to H3 and the characteristic curves of the differential equation are transversal to mesh lines on the closure of the domain of integration. When characteristics are parallel to mesh lines on a subset of positive measure the scheme is only first-order convergent in the L2-norm. However, if transversality fails on part of the outflow boundary only, then the cell-vertex scheme is second-order convergent in a weighted L2-norm.
Local Grayvalue Invariants for Image Retrieval
Authors: Cordelia Schmid, Roger Mohr
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1997)

This paper addresses the problem of retrieving images from large image databases. The method is based on local grayvalue invariants which are computed at automatically detected interest points. A voting algorithm and semilocal constraints make retrieval possible. Indexing allows for efficient retrieval from a database of more than 1,000 images. Experimental results show correct retrieval in the case of partial visibility, similarity transformations, extraneous features, and small perspective deformations.
Stochastic Verification Theorems within the Framework of Viscosity Solutions
Authors: Xun Yu Zhou, Jiongmin Yong, Xunjing Li
Venue: SIAM Journal on Control and Optimization (1997)

This paper studies controlled systems governed by Ito's stochastic differential equations in which control variables are allowed to enter both drift and diffusion terms. A new verification theorem is derived within the framework of viscosity solutions without involving any derivatives of the value functions. This theorem is shown to have wider applicability than the restrictive classical verification theorems, which require the associated dynamic programming equations to have smooth solutions. Based on the new verification result, optimal stochastic feedback controls are obtained by maximizing the generalized Hamiltonians over both the control regions and the superdifferentials of the value functions.
Computing moments of objects enclosed by piecewise polynomial surfaces
Authors: Carlos Gonzalez-Ochoa, Scott McCammon, Jörg Peters
Venue: ACM Transactions on Graphics (TOG) (1998)

Combining a polynomial free-form surface representation with Gauss' divergence theorem allows efficient and exact calculation of the moments of the enclosed objects. For example, for an cubic representation, volume, center of mass, and the inertia tensor can be computed in seconds even for complex objects with serval thousand patches while change due to local modification of the surface geometry can be computed in real-time as feedback for animation or design. Speed and simplicity of the approach allow solving the inverse problem of modeling to match prescribed moments.
On the Scalability of 2-D Discrete Wavelet Transform Algorithms
Authors: José Fridman, Elias S. Manolakos
Venue: Multidimensional Systems and Signal Processing (1997)

The ability of a parallel algorithm to make efficient use of increasing computational resources is known as its scalability. In this paper, we develop four parallel algorithms for the 2-dimensional Discrete Wavelet Transform algorithm (2-D DWT), and derive their scalability properties on Mesh and Hypercube interconnection networks. We consider two versions of the 2-D DWT algorithm, known as the Standard (S) and Non-standard (NS) forms, mapped onto P processors under two data partitioning schemes, namely checkerboard (CP) and stripped (SP) partitioning. The two checkerboard partitioned algorithms on the cut-through-routed (CT-routed) Mesh are scalable as M^{2}=\Omega(P\log P) (Non-standard form, NS-CP), and as M^{2}=\Omega(P\log^{2}P) (Standard form, S-CP); while on the store-and-forward-routed (SF-routed) Mesh and Hypercube they are scalable as M^2=\Omega(P^{\frac{3}{3-\gamma}}) (NS-CP), and as M^2=\Omega(P^{\frac{2}{2-\gamma}}) (S-CP), respectively, where M^{2} is the number of elements in the input matrix, and \gamma\in (0,1) is a parameter relating M to the number of desired octaves J as J=\lceil \gamma \log M \rceil. On the CT-routed Hypercube, scalability of the NS-form algorithms shows similar behavior as on the CT-routed Mesh. The Standard form algorithm with stripped partitioning (S-SP) is scalable on the CT-routed Hypercube as M^{2}=\Omega(P^{2}), and it is unscalable on the CT-routed Mesh. Although asymptotically the stripped partitioned algorithm S-SP on the CT-routed Hypercube would appear to be inferior to its checkerboard counterpart S-CP, detailed analysis based on the proportionality constants of the isoefficiency function shows that S-SP is actually more efficient than S-CP over a realistic range of machine and problem sizes. A milder form of this result holds on the CT- and SF-routed Mesh, where S-SP would, asymptotically, appear to be altogether unscalable.
Uniform Dynamic Self-Stabilizing Leader Election
Authors: Shlomi Dolev, Amos Israeli, Shlomo Moran
Venue: IEEE Transactions on Parallel and Distributed Systems (1997)

A distributed system is self-stabilizing if it can be started in any possible global state. Once started the system regains its consistency by itself, without any kind of outside intervention. The self-stabilization property makes the system tolerant to faults in which processors exhibit a faulty behavior for a while and then recover spontaneously in an arbitrary state. When the intermediate period in between one recovery and the next faulty period is long enough, the system stabilizes. A distributed system is uniform if all processors with the same number of neighbors are identical. A distributed system is dynamic if it can tolerate addition or deletion of processors and links without reinitialization. In this work, we study uniform dynamic self-stabilizing protocols for leader election under readwrite atomicity. Our protocols use randomization to break symmetry. The leader election protocol stabilizes in $O\left( {\Delta {\cal D}\log n} \right)$ time when the number of the processors is unknown and $O\left( {\Delta {\cal D}} \right),$ otherwise. Here ¿ denotes the maximal degree of a node, ${\cal D}$ denotes the diameter of the graph and n denotes the number of processors in the graph. We introduce self-stabilizing protocols for synchronization that are used as building blocks by the leader-election algorithm. We conclude this work by presenting a simple, uniform, self-stabilizing ranking protocol.
Bounds and Characterizations of Authentication/SecrecySchemes
Authors: L. R. A. Casse, K. M. Martin, P. R. Wild
Venue: Designs, Codes and Cryptography (1998)

We consider authentication/secrecy schemes from the information theoretic approach. We extend results on unconditionally secure authentication schemes and then consider unconditionally secure authentication schemes that offer perfect L-fold secrecy. We consider both ordered and unordered secrecy. We establish entropy bounds on the encoding rules for authentication schemes with these types of secrecy. We provide some combinatorial characterizations and constructions for authentication schemes having perfect L-fold secrecy that meet these bounds.
A Review and Empirical Evaluation of Feature Weighting Methods for aClass of Lazy Learning Algorithms
Authors: Dietrich Wettschereck, David W. Aha, Takao Mohri
Venue: Artificial Intelligence Review (1997)

Many lazy learning algorithms are derivatives of the k-nearest neighbor (k-NN) classifier, which uses a distance function to generate predictions from stored instances. Several studies have shown that k-NN&lsquo;s performance is highly sensitive to the definition of its distance function. Many k-NN variants have been proposed to reduce this sensitivity by parameterizing the distance function with feature weights. However, these variants have not been categorized nor empirically compared. This paper reviews a class of weight-setting methods for lazy learning algorithms. We introduce a framework for distinguishing these methods and empirically compare them. We observed four trends from our experiments and conducted further studies to highlight them. Our results suggest that methods which use performance feedback to assign weight settings demonstrated three advantages over other methods: they require less pre-processing, perform better in the presence of interacting features, and generally require less training data to learn good settings. We also found that continuous weighting methods tend to outperform feature selection algorithms for tasks where some features are useful but less important than others.
Norms and Inequalities Related to Schur Products of Rectangular Matrices
Authors: Wenchao Huang, Chi-Kwong Li, Hans Schneider
Venue: SIAM Journal on Matrix Analysis and Applications (1997)

We consider operator norms on rectangular matrices. When the underlying vector norms are semiabsolute/absolute and the matrices are nonnegative, we obtain an inequality involving Schur (Hadamard) products of fractional Schur powers of matrices and the product of the fractional powers of the norms of the matrices. This leads naturally to the concept of fractional Schur (nonnegative) submultiplicativity factors for a norm. As a corollary, we obtain a necessary and sufficient condition for a norm to be Schur submultiplicative on nonnegative matrices. We also consider the relation of the least fractional Schur submultiplicativity factor and the least Schur submultiplicativity factor for general matrices, and we prove some necessary and sufficient conditions for Schur submultiplicativity.
Optimal Control of Linear Periodic Resonant Systems in Hilbert Spaces
Authors: Viorel Barbu
Venue: SIAM Journal on Control and Optimization (1997)

This work concerns existence, the maximum principle, and synthesis for optimal control problems with linear periodic dynamics in Hilbert spaces in the resonant case. Applications to distributed and boundary periodic control problems are given.
A Competitive Analysis of Load Balancing Strategiesfor Parallel Ray Tracing
Authors: Alan Heirich, James Arvo
Venue: The Journal of Supercomputing (1998)

This paper examines the effectiveness of load balancing strategies for ray tracing on large parallel computer systems and cluster computers. Popular static load balancing strategies are shown to be inadequate for rendering complex images with contemporary ray tracing algorithms, and for rendering NTSC resolution images on 128 or more computers. Strategies based on image tiling are shown to be ineffective except on very small numbers of computers. A dynamic load balancing strategy, based on a diffusion model, is applied to a parallel Monte Carlo rendering system. The diffusive strategy is shown to remedy the defects of the static strategies. A hybrid strategy that combines static and dynamic approaches produces nearly optimal performance on a variety of images and computer systems. The theoretical results should be relevant to other rendering and image processing applications.
Introductory computer science for general education: laboratories, textbooks, and the Internet
Authors: Ryan McFall, Gordon Stegink
Venue: ACM SIGCSE Bulletin (1997)

Many colleges and universities are experiencing the need to offer an introductory computer science course that meets some but perhaps not all the guidelines suggested for a CS 1 course. This course frequently meets institutional general education requirements and must be more than a literacy course.We discuss the implementation of such a course at Hope College. We outline the goals of the course and some novel features of the implementation, including an emphasis on graphics. We give examples of our approach to laboratories. Finally we show how we utilize the World Wide Web as a substitute for a textbook and for course administration.
A rendezvous with Linda
Authors: Kristina Lundqvist, Göran Wall
Venue: ACM SIGAda Ada Letters (1997)

The Ada 9X revision found the rendezvous mechanism too complex to implement as the communication mechanism in a distributed system. In this paper another distributed programming model, Linda, is related to the rendezvous mechanism. Linda can be used to allow tasks to communicate in a rendezvous like manner. Sequences of Linda operations that roughly corresponds to different rendezvous operations are given and a small extension of Linda is presented in order to handle more of the rendezvous constructs. Linda can be used to communicate across partitions as well as within partitions.