ppxscal/embedding_network huggingface dataset:
Computation of Homoclinic Orbits in Partial Differential Equations: An Application to Cylindrical Shell Buckling
Authors: G. J. Lord, A. R. Champneys, G. W. Hunt
Venue: SIAM Journal on Scientific Computing (1999)

This paper concerns numerical computation of localized solutions in partial differential equations (PDEs) on unbounded domains. The application is to the von Kármán--Donnell equations, a coupled system of elliptic equations describing the equilibrium of an axially compressed cylindrical shell. Earlier work suggests that axially localized solutions are the physically preferred buckling modes. Hence the problem is posed on a cylindrical domain that is unbounded axially and solutions are sought which are homoclinic in the axial variable and periodic circumferentially.The numerical method is based on a Galerkin spectral decomposition circumferentially to pose ordinary differential equations (ODEs) in the unbounded coordinate. Methods for location and parameter continuation of homoclinic solutions of ODEs are then adapted, making special use of the symmetry and reversibility properties of solutions observed experimentally. Thus a formally well-posed continuation problem is reduced to a rotational subgroup circumferentially and posed over a truncation of the half-interval axially. The method for location of solutions makes use of asymptotic approximations where available. More generally, an adaptation of the "successive continuation" shooting method is used in the lowest possible number of circumferential modes, followed by additional homotopies to add more modes by continuation in the strength of nonlinear mode-interaction terms.The method is illustrated step by step to produce a variety of homoclinic solutions of the equations and compute their bifurcation diagrams as the loading parameter varies. Good agreement with experimental data is found. All computations are performed using AUTO. The techniques illustrated here for the von Kármán--Donnell equations are applicable to a wider class of PDEs.
APPN&mdash;Communications Scenarios
Authors: Jesper Yun Nilausen
Venue: International Journal of Network Management (1996)

In this second article in the series on managing APPN networks we will go through several APPN communications scenarios and analyse how the APPN protocol works when resources are found, routes are selected and communications sessions are establisheestablished and maintained.
Structure Recovery with Multiple Cameras from Scaled Orthographic and Perspective Views
Authors: Atsushi Marugame, Jiro Katto, Mutsumi Ohta
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1999)

This paper presents a novel framework for Euclidean structure recovery utilizing a scaled orthographic view and perspective views simultaneously. A scaled orthographic view is introduced in order to automatically obtain camera parameters such as camera positions, orientation, and focal length. Scaled orthographic properties enable all camera parameters to be calculated implicitly and perspective properties enable a Euclidean structure to be recovered. The method can recover a Euclidean structure with at least seven point correspondences across a scaled orthographic view and perspective views. Experimental results for both computed and natural images verify that the method recovers structure with sufficient accuracy to demonstrate potential utility. The proposed method can be applied to an interface for 3D modeling, recognition, and tracking.
Computing components and projections of curves over finite fields
Authors: Joachim vonzur Gathen, Igor Shparlinski
Venue: SIAM Journal on Computing (1999)

This paper provides an algorithmic approach to some basic algebraic and combinatorial properties of algebraic curves over finite fields: the number of points on a curve or a projection, its number of absolutely irreducible components, and the property of being "exceptional."
A Biased Random Instruction Generation Environmentfor Architectural Verification of Pipelined Processors
Authors: Ta-Chung Chang, Vikram Iyengar, Elizabeth M. Rudnick
Venue: Journal of Electronic Testing: Theory and Applications (2000)

Architectural verification is a critical aspect of the microprocessor design cycle. In this paper, we present a design verification environment centered around a biased random instruction generator for simulation-based architectural verification of pipelined microprocessors. The instruction generator uses biases specified by the user to generate instruction sequences for simulation. These biases are not hard-coded and can thus be changed depending on the specific areas in the design and type of design errors being targeted. Correctness checking is achieved using assertion checking and end-of-state comparison with a high-level architectural model. Several architectural-level errors are introduced into a behavioral model of the DLX processor to investigate the processor's response in the presence of design errors. Simulation experiments conducted using the behavioral model show that biased random instruction sequences provide higher coverage of RTL conditional branches and design errors than random instruction sequences or manually-generated test programs. Furthermore, instruction sequences containing a high percentage of read-after-write (RAW) and control dependencies are the most useful.
MiBiblio: personal spaces in a digital library universe
Authors: Lourdes Fernández, J. Alfredo Sánchez, Alberto García
Venue: Proceedings of the fifth ACM conference on Digital libraries (2000)

This paper describes MiBiblio, a highly personalizable interface to large collections in digital libraries. MiBiblio allows users to create virtual places we term personal spaces. As users find useful items in the repositories, they organize these items and keep them handy in their personal spaces for future use. Personal spaces may also be updated by user agents.
Analysis and design of low-phase-noise ring oscillators
Authors: Liang Dai, Ramesh Harjani
Venue: Proceedings of the 2000 international symposium on Low power electronics and design (2000)

This paper presents a framework for CMOS ring oscillator phase noise analysis for given power consumption specifications. This model considers both linear and nonlinear operations. It indicates that fast rail-to-rail switching has to be achieved for low phase noise and that the up-conversion of low-frequency noise from the current bias/control circuit can be significant. Our phase noise model is validated via simulation and measurement results. We also present a coupled-ring oscillator whose phase noise is -114 dBc/Hz at a 600 kHz offset from the 960 MHz carrier frequency.
Pomegranate: a fully scalable graphics architecture
Authors: Matthew Eldridge, Homan Igehy, Pat Hanrahan
Venue: Proceedings of the 27th annual conference on Computer graphics and interactive techniques (2000)

Pomegranate is a parallel hardware architecture for polygon rendering that provides scalable input bandwidth, triangle rate, pixel rate, texture memory and display bandwidth while maintaining an immediate-mode interface. The basic unit of scalability is a single graphics pipeline, and up to 64 such units may be combined. Pomegranate's scalability is achieved with a novel &ldquo;sort-everywhere&rdquo; architecture that distributes work in a balanced fashion at every stage of the pipeline, keeping the amount of work performed by each pipeline uniform as the system scales. Because of the balanced distribution, a scalable network based on high-speed point-to-point links can be used for communicating between the pipelines. Pomegranate uses the network to load balance triangle and fragment work independently, to provide a shared texture memory and to provide a scalable display system. The architecture provides one interface per pipeline for issuing ordered, immediate-mode rendering commands and supports a parallel API that allows multiprocessor applications to exactly order drawing commands from each interface. A detailed hardware simulation demonstrates performance on next-generation workloads. Pomegranate operates at 87-99% parallel efficiency with 64 pipelines, for a simulated performance of up to 1.10 billion triangles per second and 21.8 billion pixels per second.
Webware: a course about the Web
Authors: David Finkel, Isabel F. Cruz
Venue: ACM SIGCSE Bulletin (1999)

Sophisticated applications and software development on the Web demand an extensive and thorough understanding of a variety of computer science disciplines, as well as providing their own set of issues. Therefore, we have created an advanced undergraduate computer science course called Webware: Computational Technology for Network Information Systems that builds upon and extends knowledge previously gathered by the students. We describe its contents, our teaching experience, and address the challenges of teaching both the foundations and current technological issues of Web programming.
Relative Perturbation Theory: I. Eigenvalue and Singular Value Variations
Authors: Ren-Cang Li
Venue: SIAM Journal on Matrix Analysis and Applications (1998)

The classical perturbation theory for Hermitian matrix eigenvalue and singular value problems provides bounds on the absolute differences between approximate eigenvalues (singular values) and the true eigenvalues (singular values) of a matrix. These bounds may be bad news for small eigenvalues (singular values), which thereby suffer worse relative uncertainty than large ones. However, there are situations where even small eigenvalues are determined to high relative accuracy by the data much more accurately than the classical perturbation theory would indicate. In this paper, we study how eigenvalues of a Hermitian matrix A change when it is perturbed to $\wtd A=D^*AD$, where D is close to a unitary matrix, and how singular values of a (nonsquare) matrix B change when it is perturbed to $\wtd B=D_1^*BD_2$, where D1 and D2 are nearly unitary. It is proved that under these kinds of perturbations small eigenvalues (singular values) suffer relative changes no worse than large eigenvalues (singular values). Many well-known perturbation theorems, including the Hoffman--Wielandt and Weyl--Lidskii theorems, are extended.
Technology Road Map to Methodologies for Mixed-Signal System Design Simulation
Authors: Robert L. Ewing
Venue: Analog Integrated Circuits and Signal Processing (1999)

Unfortunately, the best solution for one mixed-signal design, is not the best solution for all mixed-signal designs. This is especially true in light of today&lsquo;s microwave applications that span the range from low-power, low-performance type of devices, through high-power, high-frequency and high-performance applications. Digital designs are automated through the use of the VHDL hardware description language, while the mixed-signal counterparts are automated using the newly developed VHDL-AMS extension. The essential ingredients for mixed-signal design fall into the methodologies of scalable functionality, robust design and feedback techniques. Scalable functionality refers to the non-conventional methodology of dimensional analysis for establishing magnitude relationships between mixed-signal system variables. Robust design of a mixed-signal system, involves the blending of the z-domain (digital) and the s-domain (continuous), resulting in the wp-domain. Robust feedback involves the inherit feedback nature of mixed-signal systems, by providing a methodology of design that emphasizes the use of feedback for achieving the desired robust system performance tolerances despite device parameter uncertainty and noise disturbances.
An Experimental Evaluation of Integrating Machine Learning with Knowledge Acquisition
Authors: Geoffrey I. Webb, Jason Wells, Zijian Zheng
Venue: Machine Learning (1999)

Machine learning and knowledge acquisition from experts have distinct capabilities that appear to complement one another. We report a study that demonstrates the integration of these approaches can both improve the accuracy of the developed knowledge base and reduce development time. In addition, we found that users expected the expert systems created through the integrated approach to have higher accuracy than those created without machine learning and rated the integrated approach less difficult to use. They also provided favorable evaluations of both the specific integrated software, a system called The Knowledge Factory, and of the general value of machine learning for knowledge acquisition.
Integral Ratio: A New Class of Global Thresholding Techniques for Handwriting Images
Authors: Yan Solihin, C. G. Leedham
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1999)

In this paper, we propose a new class of histogram based global thresholding techniques called Integral Ratio. They are designed to threshold gray-scale handwriting images and separate the handwriting from the background. The following tight requirements must be met: 1) all the details of the handwriting are to be retained, 2) the writing paper used may contain strong colored and/or patterned background which must be removed, and 3) the handwriting may be written using a wide variety of pens such as a fountain pen, ballpoint pen, or pencil. A specific application area which requires these tight requirements is forensic document examination, where a handwritten document is often considered as legal evidence and the handwriting must not be tampered with or modified in any way. The proposed class of techniques is based on a two stage thresholding approach requiring each pixel of a handwritten image to be placed into one of three classes: foreground, background, and a fuzzy area between them where it is hard to determine whether a pixel belongs to the foreground or the background. Two techniques, Native Integral Ratio (NIR) and Quadratic Integral Ratio (QIR), were created based on this class and tested against two well-known thresholding techniques: Otsu's technique and the Entropy thresholding technique. We found that QIR has superior performance compared to all the other techniques tested.
Element-by-Element Construction of Wavelets Satisfying Stability and Moment Conditions
Authors: Wolfgang Dahmen, Rob Stevenson
Venue: SIAM Journal on Numerical Analysis (1999)

In this paper, we construct a class of locally supported wavelet bases for C0 Lagrange finite element spaces on possibly nonuniform meshes on \(n\)-dimensional domains or manifolds. The wavelet bases are stable in the Sobolev spaces \(\mathcal{H}^s\) for \(|s|The construction of the wavelets consists of two parts: An implicit part involves some computations on a reference element which, for each type of finite element space, have to be performed only once. In addition there is an explicit part which takes care of the necessary adaptations of the wavelets to the actual mesh. The only condition we need for this construction to work is that the refinements of initial elements are uniform. We will show that the wavelet bases can be implemented efficiently.
Low power sequential circuit design by using priority encoding and clock gating
Authors: Xunwei Wu, Massoud Pedram
Venue: Proceedings of the 2000 international symposium on Low power electronics and design (2000)

This paper presents a state assignment technique called priority encoding, which uses multi-code assignment plus clock gating to reduce power dissipation in sequential circuits. The basic idea is to assign multiple codes to states so as to enable more effective clock gating in the sequential circuit. Practical design examples are studied and simulated by PSPICE. Experimental results demonstrate that the priority encoding technique can result in sizable power saving.
Minimal Degree Coprime Factorization of Rational Matrices
Authors: Cristian Oara, Andras Varga
Venue: SIAM Journal on Matrix Analysis and Applications (1999)

Given a rational matrix G with complex coefficients and a domain $\Gamma$ in the closed complex plane, both arbitrary, we develop a complete theory of coprime factorizations of G over $\Gamma$, with denominators of McMillan degree as small as possible. The main tool is a general pole displacement theorem which gives conditions for an invertible rational matrix to dislocate by multiplication a part of the poles of G. We apply this result to obtain the parametrized class of all coprime factorizations over $\Gamma$ with denominators of minimal McMillan degree nb---the number of poles of G outside $\Gamma$. Specific choices of the parameters and of $\Gamma$ allow us to determine coprime factorizations, as for instance, with polynomial, proper, or stable factors. Further, we consider the case in which the denominator has a certain symmetry, namely it is J all-pass with respect either to the imaginary axis or to the unit circle. We give necessary and sufficient solvability conditions for the problem of coprime factorization with J all-pass denominator of McMillan degree nb and, when a solution exists, we give a construction of the class of coprime factors. When no such solution exists, we discuss the existence of, and give solutions to, coprime factorizations with J all-pass denominators of minimal McMillan degree (>nb). All the developments are carried out in terms of descriptor realizations associated with rational matrices, leading to explicit and computationally efficient formulas.
Classroom Note: What Makes a Good Friend? The Mathematics of Rock Climbing
Authors: Matthew Bonney, Joshua Coaplen, Erik Doeff
Venue: SIAM Review (1998)

The shape of the cams used in rock climbing friends is derived using a linear system of differential equations.
Solving Hyperbolic PDEs Using Interpolating Wavelets
Authors: Mats Holmström
Venue: SIAM Journal on Scientific Computing (1999)

A method is presented for adaptively solving hyperbolic PDEs. The method is based on an interpolating wavelet transform using polynomial interpolation on dyadic grids. The adaptability is performed automatically by thresholding the wavelet coefficients. Operations such as differentiation and multiplication are fast and simple due to the one-to-one correspondence between point values and wavelet coefficients in the interpolating basis. Treatment of boundary conditions is simplified in this sparse point representation (SPR). Numerical examples are presented for one- and two-dimensional problems. It is found that the proposed method outperforms a finite difference method on a uniform grid for certain problems in terms of flops.
Document overlap detection system for distributed digital libraries
Authors: Krisztián Monostori, Arkdy Zaslavsky, Heinz Schmidt
Venue: Proceedings of the fifth ACM conference on Digital libraries (2000)

In this paper we introduce the MatchDetectReveal(MDR) system, which is capable of identifying overlapping and plagiarised documents. Each component of the system is briefly described. The matching-engine component uses a modified suffix tree representation, which is able to identify the exact overlapping chunks and its performance is also presented.
The Weight Hierarchy of Hermitian Codes
Authors: Angela I. Barbero, Carlos Munuera
Venue: SIAM Journal on Discrete Mathematics (2000)

We compute the complete weight hierarchies of all Hermitian codes. The tools used are the arithmetic of Hermitian curves and the order bound on the generalized Hamming weights.
Algorithm 791: TSHEP2D: cosine series Shepard method for bivariate interpolation of scattered data
Authors: Robert J. Renka, Ron Brown
Venue: ACM Transactions on Mathematical Software (TOMS) (1999)

We describe a new algorithm for scattered data interpolation. It is based on a modified Shepard method similar to that of Algorithm 660 but uses 10-parameter cosine series nodal functions in place of quadratic polynomials. Also, the interpolant has continuous second partial derivatives. An accompanying survey article presents test results that show the method to be more accurate than polynomial-based methods in terms of reproducing test functions with large variations and steep gradients.
A Linear Time Algorithm for Embedding Graphs in an Arbitrary Surface
Authors: Bojan Mohar
Venue: SIAM Journal on Discrete Mathematics (1999)

For an arbitrary fixed surface S, a linear time algorithm is presented that for a given graph G either finds an embedding of G in S or identifies a subgraph of G that is homeomorphic to a minimal forbidden subgraph for embeddability in S. A side result of the proof of the algorithm is that minimal forbidden subgraphs for embeddability in S cannot be arbitrarily large. This yields a constructive proof of the result of Robertson and Seymour that for each closed surface there are only finitely many minimal forbidden subgraphs. The results and methods of this paper can be used to solve more general embedding extension problems.
Stability of Steady Solutions of Burgers's Equation
Authors: Gunilla Kreiss, Heinz-Otto Kreiss
Venue: SIAM Journal on Numerical Analysis (1998)

We develop tools to discuss the stability of viscous shock profiles for conservation laws. The technique is based on replacing the far field regions by boundary conditions that describe the effect of the outer solution on the solution in the shock layer region. We apply the technique to Burgers's equation and prove stability for perturbations that are not localized in space.
DNA sequence variation among humans and apes (abstract only)
Authors: Henrik Kaessmann, Ingo Ebersberger, Victor Wiebe, Rikard Erlandsson, Jim F. Wilson, Carsten Schwarz, Michaela Winkler, Svante Pääbo
Venue: Proceedings of the fourth annual international conference on Computational molecular biology (2000)

In order to shed light on the rate and mode of evolution of DNA sequence evolution in the germ line of humans and chimpanzees, we have sequenced 136 kb around the human ZFY gene as well as a total of 180 kb of genomic DNA surrounding the ZFX and ZFY genes on the chimpanzee X and Y chromosome, respectively. The comparison of the orthologous sequences on the human and chimpanzee sex chromosomes show that whereas the ZFX region display 0.8% substitutional differences between the two species, the ZFY region display 1.5% differences. By contrast, insertions and deletions show no difference between the two regions. Interestingly, transversions show a much more drastic preponderance in the male germ line than transitions, and the insertion of retroviral-like elements seem to occur more frequently in the male than in the female germ line. While data on nucleotide sequence variation in the human nuclear genome have begun to accumulate through comparative sequencing projects at several diseases-associated genes, little is known about genomic variation in non-coding parts of the human genome and practically nothing about the variation in chimpanzee genome. In order to begin to gauge the extent and pattern of point substitutional variation in the non-transcribed parts of the human genome, we have sequenced 10 kb of non-coding DNA in a region of low recombination at Xq13.3 from 70 humans representing all major language groups of the world. In addition, the same sequence has been determined from 30 chimpanzees, representing all major subspecies, as well as bonobos. Comparison to humans reveals an almost four-fold higher diversity and a three-fold greater age of the most recent common ancestor of the chimpanzee sequences. Phylogenetic analyses show the sequences from the different chimpanzee subspecies to be intermixed and the distance between some chimpanzee sequences to be greater than the distance between them and the bonobo sequences. These data, as well as preliminary work in the other great apes, indicate that the human genome is unique in carrying extremely little nucleotide diversity.