ppxscal/embedding_network huggingface dataset:
A Combined Method for Maintaining Large Indices in Multiprocessor Multidisk Environments
Authors: G. Matsliach, O. Shmueli
Venue: IEEE Transactions on Knowledge and Data Engineering (1994)

Consider the problem of maintaining large indices (or secondary memory indices) in a multiprocessor multidisk environment in which each processor has a dedicated secondary memory (one disk or more). The processors either reside in the same site and communicate via shared memory, or reside in different sites and communicate via a local broadcast network. The straightforward method (SFM) for maintaining such an index, which is commonly called declustering, is to partition the index records equally among the processors, each of which maintains its part of the index in a local B/sup tree. In prior work (Inform. Processing Lett., vol. 34, pp. 313-321, May 1990), we have presented another method, called the "totally distributed B/sup tree" (TDB) method, in which all processors together implement a "wide" B/sup tree. There are settings in which the second method is better than the first method, and vice versa. In this paper, we present a new method, called the combined distribution method (CDM), that combines the ideas underlying SFM and TDB. In tightly coupled environments, CDM outperforms both SFM and TDB in almost all practical settings (in many settings by more than 30%). This is shown by an approximate analysis and verified by simulations. Note that CDM's approach can improve performance in database systems that use a RAID (redundant array of inexpensive disks).
Stokes Operators via Limit Monodromy of Generic Perturbation
Authors: A. A. Glutsuk
Venue: Journal of Dynamical and Control Systems (1999)

We show that for a generic deformation of a linear analytic differential equation with an irregular singularity of order 1 of a generic (nonresonant) type, Stokes operators of the nonperturbed equation are limits of transition operators between appropriate eigenbases of the monodromy operators of the perturbed equation. We prove a generalization of this statement for arbitrary degree nonresonant irregular singularity.
On the Global Dynamics of a Controlled Viscous Burgers' Equation
Authors: Ch. I. Byrnes, D. S. Gilliam, V. I. Shubov
Venue: Journal of Dynamical and Control Systems (1998)

In this paper we consider a boundary control problem for a forced Burgers' equation in a Hilbert state space consisting of square integrable functions on a finite interval. Our first main result consists in proving the global in time existence of solutions of the closed loop boundary control system for arbitrary L2 initial data and quite general forcing terms (disturbances). For the unforced problem, our main interest is in stability of equilibria, while for the forced problem we are interested in steady state behavior of solutions. We note that the uncontrolled (open loop), unforced problem is not asymptotically stable on L2. However, for positive gains we show that the unforced closed loop system is globally Lyapunov stable and locally exponentially stable. In addition, for nonzero stationary forcing, we show that there is a local absorbing ball and that the corresponding nonlinear semigroup is compact for all t > 0. Using this fact, we are able to deduce several consequences regarding the existence and properties of local attractors. Our method of proof is based on a systematic investigation of the smoothing properties of the controlled dynamics. In particular we establish various regularity results for the dynamics of the closed loop system.
Robust Estimation for Range Image Segmentation and Reconstruction
Authors: X. Yu, T. D. Bui, A. Krzyzak
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1994)

This correspondence presents a segmentation and fitting method using a new robust estimation technique. We present a robust estimation method with high breakdown point which can tolerate more than 80% of outliers. The method randomly samples appropriate range image points in the current processing region and solves equations determined by these points for parameters of selected primitive type. From K samples, we choose one set of sample points that determines a best-fit equation for the largest homogeneous surface patch in the region. This choice is made by measuring a residual consensus (RESC), using a compressed histogram method which is effective at various noise levels. After we get the best-fit surface parameters, the surface patch can be segmented from the region and the process is repeated until no pixel left. The method segments the range image into planar and quadratic surfaces. The RESC method is a substantial improvement over the least median squares method by using histogram approach to inferring residual consensus. A genetic algorithm is also incorporated to accelerate the random search.
Requirements for Advanced Year 2000 Maintenance Tools
Authors: Philip H. Newcomb, Melvin Scott
Venue: Computer (1997)

Most of today's maintenance tools are not sophisticated enough to handle Y2K maintenance on complex, mission-critical systems. Organizations should demand more from maintenance tools, yet there exists skepticism within the communities that are most in need. Perhaps the only positive side-effect of the Y2K problem is that it may cause the information technology community to finally adopt automated maintenance support tools. It is impossible to completely automate Y2K maintenance. But we believe specialized maintenance tools can significantly reduce the labor required to inspect, assess, correct, and test the affected applications. Maintenance tools that can magnify and amplify human insight and action-knowledge-based tools-are especially relevant. This article describes the general requirements for advanced Y2K maintenance tool support. Here we report what we have learned and are learning about the architecture, tools, and process requirements that will enable us to adapt our knowledge-based reengineering, reuse, and translation tools to the Y2K problem. We hope to raise expectations for maintenance tools and thereby alleviate some of the pessimism currently surrounding the subject. Effective tools support can mean the difference Y2K survivability and information systems meltdown.
Surviving Global Software Development
Authors: Christof Ebert, Philip De Neve
Venue: IEEE Software (2001)

Alcatel aims for global software development in its switching and routing business. Although there are many good reasons to globally distribute development activities, success is not guaranteed by just opening a development center in a low-cost region. The authors summarize experiences and distill best practices from true global software development involving over 5,000 engineers on almost all the continents.
Accelerating Multimedia with Enhanced Microprocessors
Authors: Ruby B. Lee
Venue: IEEE Micro (1995)

This article defines multimedia, and motivates the use of multimedia benchmarks in the design of general-purpose computers and general-purpose microprocessors. It describes a minimalistic set of multimedia instructions introduced into PA-RISC microprocessors that allow sophisticated SIMD-MIMD parallelism to be implemented, with insignificant changes to the underlying microprocessor. This enabled for the first time, a video decoder implemented in software to attain MPEG video and audio decompression and playback at realtime rates of 30 frames per second, on an entry-level workstation.Unlike previous approaches, no special DSP, coprocessor or functional unit was added to the microprocessor. The multimedia instructions include parallel subword add, subtract, average, shift_left_and_add andshift_right_and_add instructions. Signed, and a novel form of unsigned saturation, is also supported. These general-purpose parallel subword instructions are useful for accelerating a variety of multimedia programs.
Spectral Element Methods for Transitional Flows in Complex Geometries
Authors: Paul F. Fischer, Gerald W. Kruse, Francis Loth
Venue: Journal of Scientific Computing (2002)

We describe the development and implementation of an efficient spectral element code for simulating transitional flows in complex three-dimensional domains. Critical to this effort is the use of geometrically nonconforming elements that allow localized refinement in regions of interest, coupled with a stabilized high-order time-split formulation of the semi-discrete Navier&ndash;Stokes equations. Simulations of transition in a model of an arteriovenous graft illustrate the potential of this approach in biomechanical applications.
Design of Residue Generators and Multioperand Modular Adders Using Carry-Save Adders
Authors: S. J. Piestrak
Venue: IEEE Transactions on Computers (1994)

Residue generator is an essential building block of encoding/decoding circuitry for arithmetic error detecting codes and binary-to-residue number system (RNS) converter. In either case, a residue generator is an overhead for a system and as such it should be built with minimum amount of hardware and should not compromise the speed of a system. Multioperand modular adder (MOMA) is a computational element used to implement various operations in digital signal processing systems using RNS. A comprehensive study of new residue generators and MOMA's is presented. The design methods given here take advantage of the periodicity of the series of powers of 2 taken module A (A is a module). Four design schemes of the n-input residue generators mod A, which are best suited for various pairs of n and A, are proposed. Their pipelined versions can be clocked with the cycle determined by the delay of a full-adder and a latch. A family of design methods for parallel and word-serial, using similar concepts, is also given. Both classes of circuits employ new highly-parallel schemes using carry-save adders with end-around carry and a minimal amount of ROM and are well-suited for VLSI implementation. They are faster and use less hardware than similar circuits known to date. One of the MOMA's can be used to build a high-speed residue-to-binary converter based on the Chinese remainder theorem.
A Guide to the Literature on Learning Probabilistic Networks from Data
Authors: Wray Buntine
Venue: IEEE Transactions on Knowledge and Data Engineering (1996)

This literature review discusses different methods under the general rubric of learning Bayesian networks from data, and includes some overlapping work on more general probabilistic networks. Connections are drawn between the statistical, neural network, and uncertainty communities, and between the different methodological communities, such as Bayesian, description length, and classical statistics. Basic concepts for learning and Bayesian networks are introduced and methods are then reviewed. Methods are discussed for learning parameters of a probabilistic network, for learning the structure, and for learning hidden variables. The presentation avoids formal definitions and theorems, as these are plentiful in the literature, and instead illustrates key concepts with simplified examples.
A Programmer's Guide to Sound
Authors: Tim Kientzle
Venue:  (1998)

:A Programmer's Guide To Sound provides detailed technical information about audio storage, processing, and compression, and includes tested C++ source code. Developers who want to add sound technology to their applications will find all the details they need to access low-level sound services on Win32, Mac OS, and UNIX; decompress MPEG, IMA ADPCM, and [mu]-Law data; read from WAVE, VOC, AIFF, and AU file formats; and play MIDI and MOD music files.
No Crystal Ball in the Software Industry
Venue: IEEE Software (1993)

The results of a 1989 survey conducted to assess the software-engineering capabilities of 13 prospective corporate members are discussed in a historical perspective. It is suggested that a look back at these predictions is clear evidence that the software industry grossly underestimated the effect of new hardware technology and grossly overestimated the affect of new software technology. Some advice on planning for the future of a software organization is offered.
A Fast Faddeev Array
Authors: G. M. Megson
Venue: IEEE Transactions on Computers (1992)

A systolic array for the fast computation of the Faddeev algorithm is presented. Inversion of an n*n matrix on a systolic array is known to tend to 5 n inner product steps under the assumption that no data are duplicated. The proposed Faddeev array achieves matrix inversion in just 4 n steps with O(n/sup 2/) basic cells using careful duplications of some data. The array consists of two half-arrays which compute two separate but coupled triangularizations. The coupling is resolved by an on-the-fly decoupling process which duplicates pivot row data and passes them between the arrays using only nearest neighbor connections.
Figure-Ground Segregation Using an Analog VLSI Chip
Authors: Jin Luo, Christof Koch, Bimal Mathur
Venue: IEEE Micro (1992)

An analog, parallel, computational system, built on a single, power-lean, CMOS VLSI chip, that labels all points inside a possibly incomplete and noisy contour in real time is described. The circuit performs figure-ground segregation of a scene, labeling all the points inside a designated figure by one voltage and all other parts outside this object using a different voltage value. Its behavior is shown to be robust, since small breaks in the contour are automatically sealed, providing for figure-ground segregation in a noisy environment. The two major limitations of the current figure-ground chip are its limited capability for recognizing figures with large gaps in the contour and the constraint that the figure always has to be centered.
On Rolling Back and Checkpointing in Time Warp
Authors: Hervé Avril, Carl Tropper
Venue: IEEE Transactions on Parallel and Distributed Systems (2001)

In this paper, we present a family of three algorithms which serve to perform checkpoints and to roll back Time Warp. These algorithms are primarily intended for use in simulations in which there are a large number of LPs and in which events have a small computational granularity. Important representatives of this class are VLSI and computer network simulations. In each of our algorithms, LPs are gathered into clusters via algorithms which are application dependent. In order to examine the performance of our algorithms and to compare them to Time Warp, we made use of two of the largest digital logic circuits available from the ISCAS89 benchmark series of combinational circuits. The execution time, number of states saved, and maximal memory consumption were compared to the same quantities for Time Warp. Our results indicated that each of the algorithms occupies a different point in the spectrum of possible trade-offs between memory usage and execution time, ranging from substantial memory savings (at a comparable cost in speed) to memory savings and a comparable speed to Time Warp. Hence, an important benefit of our algorithms is the ability to trade off memory requirements with execution time.
Image indexing and retrieval using signature trees
Authors: Mario A. Nascimento, Eleni Tousidou, Vishal Chitkara, Yannis Manolopoulos
Venue: Data Knowledge Engineering (2002)

Significant research has focused on determining efficient methodologies for effective and speedy retrieval in large image databases. Towards that goal, the first contribution of this paper is an image abstraction technique, called variable-bin allocation (VBA), based on signature bitstrings and a corresponding similarity metric. The signature provides a compact representation of an image based on its color content and yields better retrieval effectiveness than when using classical global color histograms (GCHs) and comparable to the one obtained when using color-coherence vectors (CCVs). More importantly however, the use of VBA signatures allows savings of 75% and 87.5% in storage overhead when compared to GCHs and CCVs, respectively. The second contribution is the improvement upon an access structure, the S-tree, exploring the concept of logical and physical pages and a specialized nearest-neighbor type of algorithm, in order to improve retrieval speed. We compared the S-tree performance when indexing the VBA signatures against the SR-tree indexing GCHs and CCVs, since SR-trees are arguably the most efficient access method for high-dimensional points. Our experimental results, using a large number of images and varying several parameters, have shown that the combination VBA/S-tree outperforms the GCH/SR-tree combination in terms of effectiveness, access speed and size (up to 45%, 25% and 70% respectively). Due to the very high-dimensionality of the CCVs their indexing, even using an efficient access structure, the SR-tree, did not seem to be a feasible alternative.
Parametrized Family of 2-D Non-factorable FIR Lossless Systems and Gr&ouml;bner Bases
Authors: Hyungju Park
Venue: Multidimensional Systems and Signal Processing (2001)

The factorability of one-dimensional (1-D) FIR lossless transfer matrices [1] in terms of Givens rotations produces the parameters that can be used for an optimal design of filter banks with prespecified filtering characteristics. Two dimensional (2-D) FIR lossless systems behave quite differently, however. Venkataraman-Levy [2] and Basu-Choi-Chiang [3] have constructed 2-D FIR paraunitary matrices of McMillan degrees (2,2) that are not factorable. Because of the state-space realization used in the construction, they are floating-point approximations, and they do not produce explicit parametrizations that can be used for optimal design process. In this paper, we formulate the lossless condition and nonfactorability condition of a 2-D FIR paraunitary matrix using multivariate polynomials in the coefficients. The resulting polynomial system can be explicitly solved with Gr&ouml;bner bases. By studying the polynomial system, we obtain a continuous one parameter family of 2-D 2&times;2 non-factorable paraunitary matrices. As an example, we get a closed-form expression for a 2-D 2&times;2 paraunitary matrix that is not factorable into rotations and delays.
A memory insensitive technique for large model simplification
Authors: Peter Lindstrom, Cláudio T. Silva
Venue: Proceedings of the conference on Visualization '01 (2001)

In this paper we propose three simple, but significant improvements to the OoCS (Out-of-Core Simplification) algorithm of Lindstrom [20] which increase the quality of approximations and extend the applicability of the algorithm to an even larger class of compute systems.The original OoCS algorithm has memory complexity that depends on the size of the output mesh, but no dependency on the size of the input mesh. That is, it can be used to simplify meshes of arbitrarily large size, but the complexity of the output mesh is limited by the amount of memory available. Our first contribution is a version of OoCS that removes the dependency of having enough memory to hold (even) the simplified mesh. With our new algorithm, the whole process is made essentially independent of the available memory on the host computer. Our new technique uses disk instead of main memory, but it is carefully designed to avoid costly random accesses.Our two other contributions improve the quality of the approximations generated by OoCS. We propose a scheme for preserving surface boundaries which does not use connectivity information, and a scheme for constraining the position of the "representative vertex" of a grid cell to an optimal position inside the cell.
A Genetic Algorithm for Multiprocessor Scheduling
Authors: E. S. H. Hou, N. Ansari, H. Ren
Venue: IEEE Transactions on Parallel and Distributed Systems (1994)

The problem of multiprocessor scheduling can be stated as finding a schedule for ageneral task graph to be executed on a multiprocessor system so that the schedulelength can be minimized. This scheduling problem is known to be NP-hard, and methodsbased on heuristic search have been proposed to obtain optimal and suboptimal solutions.Genetic algorithms have recently received much attention as a class of robust stochasticsearch algorithms for various optimization problems. In this paper, an efficient methodbased on genetic algorithms is developed to solve the multiprocessor scheduling problem.The representation of the search node is based on the order of the tasks being executedin each individual processor. The genetic operator proposed is based on the precedencerelations between the tasks in the task graph. Simulation results comparing the proposedgenetic algorithm, the list scheduling algorithm, and the optimal schedule using randomtask graphs, and a robot inverse dynamics computational task graph are presented.
A Parallelization Domain Oriented Multilevel Graph Partitioner
Authors: Eric A. Schweitz, Dharma P. Agrawal
Venue: IEEE Transactions on Computers (2002)

In this paper we present a novel multilevel graph partitioning algorithm, KACE, which uses knowledge about the domain and employs several graph transformation techniques. Both functional and structural parallelism in the sequential code are explored to improve the quality of parallel tasks. Statistical information about communication times between nodes as a function of message size and/or other factors are used to have a better estimate of balancing factors, code replication, and synchronization penalties. This enables us to use a task cohesion algorithm to obtain a coarse version of the partitioned graph. Many of KACE's pIarameters are shown to have definite impact on the parallelized program code.
Electrical Characterization of Megabit DRAMs, Part 2: Internal Testing
Authors: Jochen Kolzer, Johann. Otto
Venue: IEEE Design Test (1991)

For pt.I. see ibid., vol.8, no.3, p.36-43 (1991). Contactless tools for testing inside dynamic RAMs, including hot-spot detection, emission microscopy, scanning laser microscopy, and submicron electron beam testing, are described. Basic principles and experimental setups are described. The utility of the techniques is assessed.
A generalized unit system for concise electromagnetic formulation and accurate numerical solutions
Authors: L. Vu-Quoc, V. Srinivas, Y. Zhai
Venue: Journal of Computational Physics (2002)

We present in this paper a novel generalized unit system (GUS) for electromagnetic formulation and for improving the numerical behavior of the solution procedure by decreasing the condition number of the finite element (FE) matrices. The goal is to express, in the GUS, the governing electromagnetic equations in a form that does not involve any factors such as 4π and those related to the physical properties of vacuum. This goal is achieved by scaling all physical quantities. The scaling factors are not all free parameters, but are constrained by specific relations. We prove that there are only two free parameters, but only one is significant for minimizing the condition number of the FE matrices. Numerical examples are presented to illustrate the essential features of the proposed GUS, including the minimization of the condition number.
Infrared-Image Classification Using Hidden Markov Trees
Authors: Priya Bharadwaj, Lawrence Carin
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2002)

An image of a three-dimensional target is generally characterized by the visible target subcomponents, with these dictated by the target-sensor orientation (target pose). An image often changes quickly with variable pose. We define a class as a set of contiguous target-sensor orientations over which the associated target image is relatively stationary with aspect. Each target is in general characterized by multiple classes. A distinct set of Wiener filters are employed for each class of images, to identify the presence of target subcomponents. A Karhunen-Loeve representation is used to minimize the number of filters (templates) associated with a given subcomponent. The statistical relationships between the different target subcomponents are modeled via a hidden Markov tree (HMT). The HMT classifier is discussed and example results are presented for forward-looking-infrared (FLIR) imagery of several vehicles.