ppxscal/embedding_network huggingface dataset:
Time-compression: systems concerns, usage, and benefits
Authors: Nosa Omoigui, Liwei He, Anoop Gupta, Jonathan Grudin, Elizabeth Sanocki
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: the CHI is the limit (1999)

With the proliferation of online multimedia content and the popularity of multimedia streaming systems, it is increasingly useful to be able to skim and browse multimedia quickly. A key technique that enables quick browsing of multimedia is time-compression. Prior research has described how speech can be time-compressed (shortened in duration) while preserving the pitch of the audio. However, client-server systems providing this functionality have not been available. In this paper, we first describe the key tradeoffs faced by designers of streaming multimedia systems deploying time-compression. The implementation tradeoffs primarily impact the granularity of time-compression supported (discrete vs. continuous) and the latency (wait-time) experienced by users after adjusting degree of time-compression. We report results of user studies showing impact of these factors on the average- compression-rate achieved. We also present data on the usage patterns and benefits of time compression. Overall, we show significant time-savings for users and that considerable flexibility is available to the designers of client-server streaming systems with time compression.
Bayesian Segmentation via Asymptotic Partition Functions
Authors: Aaron D. Lanterman, Ulf Grenander, Michael I. Miller
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2000)

Asymptotic approximations to the partition function of Gaussian random fields are derived. Textures are characterized via Gaussian random fields induced by stochastic difference equations determined by finitely supported, stationary, linear difference operators, adjusted to be nonstationary at the boundaries. It is shown that as the scale of the underlying shape increases, the log-normalizer converges to the integral of the log-spectrum of the operator inducing the random field. Fitting the covariance of the fields amounts to fitting the parameters of the spectrum of the differential operator-induced random field model. Matrix analysis techniques are proposed for handling textures with variable orientation. Examples of texture parameters estimated from training data via asymptotic maximum-likelihood are shown. Isotropic models involving powers of the Laplacian and directional models involving partial derivative mixtures are explored. Parameters are estimated for mitochondria and actin-myocin complexes in electron micrographs and clutter in forward-looking infrared images. Deformable template models are used to infer the shape of mitochondria in electron micrographs, with the asymptotic approximation allowing easy recomputation of the partition function as inference proceeds.
Guillotine Subdivisions Approximate Polygonal Subdivisions: A Simple Polynomial-Time Approximation Scheme for Geometric TSP, k-MST, and Related Problems
Authors: Joseph S. B. Mitchell
Venue: SIAM Journal on Computing (1999)

We show that any polygonal subdivision in the plane can be converted into an "m-guillotine" subdivision whose length is at most $(1+{c\over m})$ times that of the original subdivision, for a small constant c. "m-Guillotine" subdivisions have a simple recursive structure that allows one to search for the shortest of such subdivisions in polynomial time, using dynamic programming. In particular, a consequence of our main theorem is a simple polynomial-time approximation scheme for geometric instances of several network optimization problems, including the Steiner minimum spanning tree, the traveling salesperson problem (TSP), and the k-MST problem.
Computing life and global technologies (abstract only)
Authors: Leroy Hood
Venue: Proceedings of the fourth annual international conference on Computational molecular biology (2000)

The view &ldquo;Biology is an informational science&rdquo; is now widely accepted&mdash;certainly catalyzed in part by the success of the Human Genome Project. There are three levels of biological information: 1-dimensional information of DNA, the 3-dimensional information of proteins, and the 4-dimensional (time variant) information of biological systems and networks. The key to deciphering biological information at each of these levels are the global technologies which analyze many genes, DNAs or proteins at one time. I will discuss several new and pioneering global technologies for genomics and proteomics. Information at each of these levels poses striking computational challenges, which will be discussed. The importance of the need for intimate interactions between biologists, computer scientists and mathematicians will also be discussed, as well as a new approach for teaching biology that may be effective for cross-disciplinary communication.
Completely Disconnecting the Complete Graph
Authors: John Ginsburg, Bill Sands
Venue: SIAM Journal on Discrete Mathematics (2000)

In this paper we consider procedures for completely disconnecting a complete graph on $n$ vertices $K_n$. By this we simply mean that we wish to remove all of the edges of $K_n$ in a sequence of steps by which the graph $K_n$ is successively transformed into the empty graph on $n$ vertices. The rules are that, on each step, we may remove at most one edge from each connected component of the present graph, and in addition we may impose a limit $w$ on the maximum number of edges we can remove at a time. What is the minimum number of steps $ f_w(n)$ it will take to completely disconnect $K_n$? The two cases considered are $ w = \infty$ and $ w = 2$. We show that the ratio of $f_w(n)$ to the number of edges of $K_n$ is asymptotic to $ 2/3$ in the first case and to $ 1/2 + \lambda(1 - \lambda) = .74194412\ldots$ in the second, where $ \lambda $ is the real root of the equation $ \lambda = 2(1 - \lambda)^3 $.
Digital library use (panel session): social practice in design and evaluation
Authors: Clifford Lynch, Christine L. Borgmen, Catherine C. Marshall, Susan Leigh Star, Geoffrey C. Bowker
Venue: Proceedings of the fifth ACM conference on Digital libraries (2000)

Digital Libraries (DLs) are social as well as technological entities. Their purpose is to help people do knowledge work, to carry knowledge processes across space and time. DLs are designed, used, and evaluated in a context of work and community. And DLs interact with this context, changing and being changed by it. Effective DLs must be designed and evaluated with a sensitivity to how knowledge is created and understood, and work is done, in a context of knowledge communities, which share practices and tools. DL use is a socially-embedded process. DL development is likewise a complex social process. This panel grows out of a book on social approaches to DL design and evaluation--currrently in press--to which the moderator and each panelist has contributed a chapter. The purpose of the panel is to present socially grounded approaches to understanding DLs; to identify and discuss major issues that arise from these approaches and, more generally, from the social nature of DLs; and to consider implications for the design and evaluation of DLs.
Real-Time Performance of Sorting Algorithms
Authors: Peter P. Puschner
Venue: Real-Time Systems (1999)

In hard real-time systems tasks must meet their deadlines under guarantee. Soft real-time tasks may miss deadlines occasionally, as long as the entire system can provide the specified quality of service.In this paper we investigate the hard and soft real-time performance of sorting algorithms and compare it to their average performance. We show in which way the adequacy of an algorithm depends on the demanded performance criterium (hard, soft, or non real-time). The results provide a guideline to select the right sorting algorithm for a given application.
Relief texture mapping
Authors: Manuel M. Oliveira, Gary Bishop, David McAllister
Venue: Proceedings of the 27th annual conference on Computer graphics and interactive techniques (2000)

We present an extension to texture mapping that supports the representation of 3-D surface details and view motion parallax. The results are correct for viewpoints that are static or moving, far away or nearby. Our approach is very simple: a relief texture (texture extended with an orthogonal displacement per texel) is mapped onto a polygon using a two-step process: First, it is converted into an ordinary texture using a surprisingly simple 1-D forward transform. The resulting texture is then mapped onto the polygon using standard texture mapping. The 1-D warping functions work in texture coordinates to handle the parallax and visibility changes that result from the 3-D shape of the displacement surface. The subsequent texture-mapping operation handles the transformation from texture to screen coordinates.
Iterated Random Functions
Authors: Persi Diaconis, David Freedman
Venue: SIAM Review (1999)

Iterated random functions are used to draw pictures or simulate large Ising models, among other applications. They offer a method for studying the steady state distribution of a Markov chain, and give useful bounds on rates of convergence in a variety of examples. The present paper surveys the field and presents some new examples. There is a simple unifying idea: the iterates of random Lipschitz functions converge if the functions are contracting on the average.
Operation and Utilization of the Racal-Datacom CMS&reg; for Tivoli TME 10 NetView
Authors: Jack J. Hillhouse
Venue: International Journal of Network Management (1996)

The optional graphics-oriented, highly intuitive CMS user interface enables a single operator to monitor and control a large multi-technology network. Racal&rsquo;s integration with NetView gives users a complete network management application.
Piranha: a scalable architecture based on single-chip multiprocessing
Authors: Luiz André Barroso, Kourosh Gharachorloo, Robert McNamara, Andreas Nowatzyk, Shaz Qadeer, Barton Sano, Scott Smith, Robert Stets, Ben Verghese
Venue: Proceedings of the 27th annual international symposium on Computer architecture (2000)

The microprocessor industry is currently struggling with higher development costs and longer design times that arise from exceedingly complex processors that are pushing the limits of instruction-level parallelism. Meanwhile, such designs are especially ill suited for important commercial applications, such as on-line transaction processing (OLTP), which suffer from large memory stall times and exhibit little instruction-level parallelism. Given that commercial applications constitute by far the most important market for high-performance servers, the above trends emphasize the need to consider alternative processor designs that specifically target such workloads. The abundance of explicit thread-level parallelism in commercial workloads, along with advances in semiconductor integration density, identify chip multiprocessing (CMP) as potentially the most promising approach for designing processors targeted at commercial servers. This paper describes the Piranha system, a research prototype being developed at Compaq that aggressively exploits chip multi-processing by integrating eight simple Alpha processor cores along with a two-level cache hierarchy onto a single chip. Piranha also integrates further on-chip functionality to allow for scalable multiprocessor configurations to be built in a glueless and modular fashion. The use of simple processor cores combined with an industry-standard ASIC design methodology allow us to complete our prototype within a short time-frame, with a team size and investment that are an order of magnitude smaller than that of a commercial microprocessor. Our detailed simulation results show that while each Piranha processor core is substantially slower than an aggressive next-generation processor, the integration of eight cores onto a single chip allows Piranha to outperform next-generation processors by up to 2.9 times (on a per chip basis) on important workloads such as OLTP. This performance advantage can approach a factor of five by using full-custom instead of ASIC logic. In addition to exploiting chip multiprocessing, the Piranha prototype incorporates several other unique design choices including a shared second-level cache with no inclusion, a highly optimized cache coherence protocol, and a novel I/O architecture.
A Space-Time Finite Element Method for the Nonlinear Schrödinger Equation: The Continuous Galerkin Method
Authors: Ohannes Karakashian, Charalambos Makridakis
Venue: SIAM Journal on Numerical Analysis (1999)

The convergence of a class of continuous Galerkin methods for the nonlinear (cubic) Schrödinger equation is analyzed in this paper. These methods allow variable temporal stepsizes as well as changing of the spatial grid from one time level to the next. We show the existence of the resulting approximations and prove optimal order error estimates in $L^\infty (L^2 ) $ and in $L^\infty (H^1 ) .$ These estimates are valid under weak restrictions on the space-time mesh. These restrictions are milder if the elliptic projection is used at every time step instead of the L2 projection. We also give superconvergence results at the temporal nodes tn.
An Accurate Measure for Multilayer Perceptron Tolerance to Weight Deviations
Authors: Jose L. Bernier, J. Ortega, M. M. Rodrì‘guez, I. Rojas, A. Prieto
Venue: Neural Processing Letters (1999)

The inherent fault tolerance of artificial neural networks (ANNs) is usually assumed, but several authors have claimed that ANNs are not always fault tolerant and have demonstrated the need to evaluate their robustness by quantitative measures. For this purpose, various alternatives have been proposed. In this paper we show the direct relation between the mean square error (MSE) and the statistical sensitivity to weight deviations, defining a measure of tolerance based on statistical sentitivity that we have called Mean Square Sensitivity (MSS); this allows us to predict accurately the degradation of the MSE when the weight values change and so constitutes a useful parameter for choosing between different configurations of MLPs. The experimental results obtained for different MLPs are shown and demonstrate the validity of our model.
Iterative Solution of Cyclically Reduced Systems Arising from Discretization of the Three-Dimensional Convection-Diffusion Equation
Authors: Chen Greif, James Varah
Venue: SIAM Journal on Scientific Computing (1998)

We consider the system of equations arising from finite difference discretization of a three-dimensional convection-diffusion model problem. This system is typically nonsymmetric. We show that performing one step of cyclic reduction, followed by reordering of the unknowns, yields a system of equations for which the block Jacobi method generally converges faster than for the original system, using lexicographic ordering. The matrix representing the system of equations can be symmetrized for a large range of the coefficients of the underlying partial differential equation, and the associated iteration matrix has a smaller spectral radius than the one associated with the original system. In this sense, the three-dimensional problem is similar to the one-dimensional and two-dimensional problems, which have been studied by Elman and Golub. The process of reduction, the suggested orderings, and bounds on the spectral radii of the associated iteration matrices are presented, followed by a comparison of the reduced system with the full system and by details of the numerical experiments.
A Fast Domain Decomposition High Order Poisson Solver
Authors: Bertil Gustafsson Lina Hemmingsson-Frändén
Venue: Journal of Scientific Computing (1999)

We present a fast high-order Poisson solver for implementation on parallel computers. The method uses deferred correction, such that high-order accuracy is obtained by solving a sequence of systems with a narrow stencil on the left-hand side. These systems are solved by a domain decomposition method. The method is direct in the sense that for any given order of accuracy, the number of arithmetic operations is fixed. Numerical experiments show that these high-order solvers easily outperform standard second-order ones. The very fast algorithm in combination with the coarser grid allowed for by the high-order method, also makes it quite possible to compete with adaptive methods and irregular grids for problems with solutions containing widely different scales.
Classification and regression: money *can* grow on trees
Authors: Johannes Gehrke, Wie-Yin Loh, Raghu Ramakrishnan
Venue: Tutorial notes of the fifth ACM SIGKDD international conference on Knowledge discovery and data mining (1999)

With over 800 million pages covering most areas of human endeavor, the World-wide Web is a fertile ground for data mining research to make a difference to the effectiveness of information search. Today, Web surfers access the Web through two dominant interfaces clicking on hyperlinks and searching via keyword queries This process is often tentative and unsatisfactory Better support is needed for expressing one's information need and dealing with a search result in more structured ways than available now. Data mining and machine learning have significant roles to play towards this end. In this paper we will survey recent advances in learning and mining problems related to hypertext in general and the Web in particular. We will review the continuum of supervised to semi-supervised to unsupervised learning problems, highlight the specific challenges which distinguish data mining in the hypertext domain from data mining in the context of data warehouses, and summarize the key areas of recent and ongoing research.
DCAS-based concurrent deques
Authors: Ole Agesen, David L. Detlefs, Christine H. Flood, Alexander T. Garthwaite, Paul A. Martin, Nir N. Shavit, Guy L. Steele,  Jr.
Venue: Proceedings of the twelfth annual ACM symposium on Parallel algorithms and architectures (2000)

The computer industry is currently examining the use of strong synchronization operations such as double compare-and-swap (DCAS) as a means of supporting non-blocking synchronization on tomorrow's multiprocessor machines. However, before such a strong primitive will be incorporated into hardware design, its utility needs to be proven by developing a body of effective non-blocking data structures using DCAS. As part of this effort, we present two new linearizable non-blocking implementations of concurrent deques using the DCAS operation. The first uses an array representation, and improves on former algorithms by allowing uninterrupted concurrent access to both ends of the deque while correctly handling the difficult boundary cases when the deque is empty or full. The second uses a linked-list representation, and is the first non-blocking unbounded-memory deque implementation. It too allows uninterrupted concurrent access to both ends of the deque.
Components and program analyses
Authors: Matthias Felleisen
Venue: ACM SIGSOFT Software Engineering Notes (2000)

Model checking has been applied quite successfully to hardware verification and shows promise for software verification. The key obstacle is the well-known state explosion problem. This report describes work done by the investigator under NSF support, in particular grants CCR 980-4736 and CCR 941-5496, to ameliorate state explosion.
On the Convergence and Applications of Generalized Simulated Annealing
Authors: P. Del Moral, L. Miclo
Venue: SIAM Journal on Control and Optimization (1999)

The convergence of the generalized simulated annealing with time-inhomogeneous communication cost functions is discussed. This study is based on the use of log-Sobolev inequalities and semigroup techniques in the spirit of a previous article by one of the authors. We also propose a natural test set approach to study the global minima of the virtual energy. The second part of the paper is devoted to the application of these results. We propose two general Markovian models of genetic algorithms and we give a simple proof of the convergence toward the global minima of the fitness function. Finally we introduce a stochastic algorithm that converges to the set of the global minima of a given mean cost optimization problem.
Numerical Solution of the Stationary Navier--Stokes Equations Using a Multilevel Finite Element Method
Authors: W. Layton, H. K. Lee, J. Peterson
Venue: SIAM Journal on Scientific Computing (1998)

The numerical implementation of a multilevel finite element method for the steady-state Navier--Stokes equations is considered. The multilevel method proposed here for the Navier--Stokes equations is a multiscale method in which the full nonlinear Navier--Stokes equations are only solved on a single coarse grid; subsequent approximations are generated on a succession of refined grids by solving a linearized Navier--Stokes problem. Two numerical examples are considered: the first is an example for which an exact solution is known and the second is the driven cavity problem. We demonstrate numerically that for an appropriate choice of grids, a two- or three-level finite element method is significantly more efficient than the standard one-level finite element method.
Audio Coding for Representation in MIDI via Pitch Detection Using Harmonic Dictionaries
Authors: Nicholas J. Sieger, Ahmed H. Tewfik
Venue: Journal of VLSI Signal Processing Systems (1998)

The search for a flexible and concise alternate representation for digital musical sound leads to the proposal for the use of the MIDI (Musical Instrument Digital Interface) protocol. The problem becomes one of automating the conversion process from sound to MIDI. This requires processing musical sound and extracting the information necessary to represent the sound as MIDI data. We have conducted studies which have led to algorithms for segmentation of the sound and pitch detection of the individual notes. We describe a novel method for pitch detection using subset selection with dictionaries containing harmonic spectra from samples of musical sounds. Examples demonstrating applicability to monophonic sounds as well as signals with multiple sound sources are given, including detection of objects in a complex background scene.
Test Generation and Fault Simulation for Cell Fault Model using Stuck-at Fault Model based Test Tools
Authors: M. Psarakis, D. Gizopoulos, A. Paschalis
Venue: Journal of Electronic Testing: Theory and Applications (1998)

Cell Fault Model (CFM) is a well-adopted functional fault model used for cell-based circuits. Despite of the wide adoption of CFM, no test tool is available for the estimation of CFM testability. The vast majority of test tools are based on the single stuck-at fault model.In this paper we introduce a method to calculate the CFM testability of a cell-based circuit using any single stuck-at fault based test tool. Cells are substituted by equivalent cells and Test Generation and Fault Simulation for CFM are emulated by Test Generation and Fault Simulation for a set of single stuck-at faults of the equivalent cells. The equivalent cell is constructed from the original cell with a simple procedure, with no need of knowledge of gate-level implementation, or its function. With the proposed methodology, the maturity and effectiveness of stuck-at fault based tools is used in testing of digital circuits, with respect to Cell Fault Model, without developing new tools.