ppxscal/embedding_network huggingface dataset:
Image-Space Decomposition Algorithms for Sort-First Parallel Volume Rendering of Unstructured Grids
Authors: Hüuseyin Kutluca, Tah&suml;in M. Kurç, Cevdet Aykanat
Venue: The Journal of Supercomputing (2000)

Twelve adaptive image-space decomposition algorithms are presented for sort-first parallel direct volume rendering (DVR) of unstructured grids on distributed-memory architectures. The algorithms are presented under a novel taxonomy based on the dimension of the screen decomposition, the dimension of the workload arrays used in the decomposition, and the scheme used for workload-array creation and querying the workload of a region. For the 2D decomposition schemes using 2D workload arrays, a novel scheme is proposed to query the exact number of screen-space bounding boxes of the primitives in a screen region in constant time. A probe-based chains-on-chains partitioning algorithm is exploited for load balancing in optimal 1D decomposition and iterative 2D rectilinear decomposition (RD). A new probe-based optimal 2D jagged decomposition (OJD) is proposed which is much faster than the dynamic-programming based OJD scheme proposed in the literature. The summed-area table is successfully exploited to query the workload of a rectangular region in constant time in both OJD and RD schemes for the subdivision of general 2D workload arrays. Two orthogonal recursive bisection (ORB) variants are adapted to relax the straight-line division restriction in conventional ORB through using the medians-of-medians approach on regular mesh and quadtree superimposed on the screen. Two approaches based on the Hilbert space-filling curve and graph-partitioning are also proposed. An efficient primitive classification scheme is proposed for redistribution in 1D, and 2D rectilinear and jagged decompositions. The performance comparison of the decomposition algorithms is modeled by establishing appropriate quality measures for load-balancing, amount of primitive replication and parallel execution time. The experimental results on a Parsytec CC system using a set of benchmark volumetric datasets verify the validity of the proposed performance models. The performance evaluation of the decomposition algorithms is also carried out through the sort-first parallelization of an efficient DVR algorithm.
On the Approximation Power of Splines on Triangulated Quadrangulations
Authors: Ming-Jun Lai, Larry L. Schumaker
Venue: SIAM Journal on Numerical Analysis (1998)

We study the approximation properties of the bivariate spline spaces %$\Srt$ ${\cal S}^r_{3r}({\hbox{$\diamondsuit$\kern-0.78em\raise0.10786ex\hbox{$+$}}})$ of smoothness r and degree 3r defined on triangulations %$\lai$ ${\hbox{$\diamondsuit$\kern-0.78em\raise0.10786ex\hbox{$+$}}}$, which are obtained from arbitrary nondegenerate convex quadrangulations by adding the diagonals of each quadrilateral.
An Efficient Extension to Mixture Techniques for Prediction and Decision Trees
Authors: Fernando C. Pereira, Yoram Singer
Venue: Machine Learning (1999)

We present an efficient method for maintaining mixtures of prunings of a prediction or decision tree that extends the previous methods for &ldquo;node-based&rdquo; prunings (Buntine, 1990&semi; Willems, Shtarkov, Tjalkens, 1995&semi; Helmbold Schapire, 1997&semi; Singer, 1997) to the larger class of edge-based prunings. The method includes an online weight-allocation algorithm that can be used for prediction, compression and classification. Although the set of edge-based prunings of a given tree is much larger than that of node-based prunings, our algorithm has similar space and time complexity to that of previous mixture algorithms for trees. Using the general online framework of Freund and Schapire (1997), we prove that our algorithm maintains correctly the mixture weights for edge-based prunings with any bounded loss function. We also give a similar algorithm for the logarithmic loss function with a corresponding weight-allocation algorithm. Finally, we describe experiments comparing node-based and edge-based mixture models for estimating the probability of the next word in English text, which show the advantages of edge-based models.
Broad-spectrum studies of log file analysis
Authors: James H. Andrews, Yingjun Zhang
Venue: Proceedings of the 22nd international conference on Software engineering (2000)

This paper reports on research into applying the technique of log file analysis for checking test results to a broad range of testing and other tasks. The studies undertaken included applying log file analysis to both unit- and system-level testing and to requirements of both safety-critical and non-critical systems, and the use of log file analysis in combination with other testing methods. The paper also reports on the technique of using log file analyzers to simulate the software under test, both in order to validate the analyzers and to clarify requirements. It also discusses practical issues to do with the completeness of the approach, and includes comparisons to other recently-published approaches to log file analysis.
Performance estimation of multiple-cache IP-based systems: case study of an interdependency problem and application of an extended shared memory model
Authors: Sungjoo Yoo, Kyoungseok Rha, Youngchul Cho, Jinyong Jung, Kiyoung Choi
Venue: Proceedings of the eighth international workshop on Hardware/software codesign (2000)

In estimating the performance of multiple-cache IP-based systems, we face a problem of interdependency between cache configuration and system behavior. In this paper, we investigate the effects of the interdependency on system performance in a case study. We present a method that gives fast and accurate estimation of system performance by simulating IP cores at the behavioral level with annotated delays and by simulating the multiple-cache communication architecture with an extended shared memory model. Experiments show the effectiveness of the proposed method.
Condensed Forms for Skew-Hamiltonian/Hamiltonian Pencils
Authors: Christian Mehl
Venue: SIAM Journal on Matrix Analysis and Applications (1999)

In this paper we consider real or complex skew-Hamiltonian/Hamiltonian pencils $\lambda S-H$, i.e., pencils where S is a skew-Hamiltonian and H is a Hamiltonian matrix. These pencils occur, for example, in the theory of continuous time, linear quadratic optimal control problems. We reduce these pencils to canonical and Schur-type forms under structure-preserving transformations, i.e., J-congruence-transformations $(\lambda S-H) \mapsto -JP^{\ast}J(\lambda S-H)P$, where P is nonsingular or unitary.
Boundary Stabilization of the Wave Equation in Almost Star-shaped Domains
Authors: Patrick Martinez
Venue: SIAM Journal on Control and Optimization (1999)

We improve several earlier results on the boundary stabilization of the wave equation in a bounded domain. First we weaken the usual geometrical conditions. Second, we improve the estimate of the decay rate in the case of polygonal domains. Then we show how to modify this method to study Maxwell's equations. The proofs are based on the construction of new multipliers, better adapted to the domain.
Optimizing the Rate of Decay of Solutions of the Wave Equation Using Genetic Algorithms: A Counterexample to the Constant Damping Conjecture
Authors: Pedro Freitas
Venue: SIAM Journal on Control and Optimization (1999)

We consider the problem of optimizing the rate of decay of solutions of the linear damped wave equation on a bounded interval. This corresponds to optimizing the spectral abscissa of the associated linear operator. By writing the damping term as a Fourier cosine series and obtaining some inequalities that the coefficients in this series have to satisfy in order that the spectral abscissa be larger than a real number $\alpha$, we are then able to use a genetic algorithm to obtain values of the spectral abscissa which are better than those given by the constant damping case. This provides a counterexample to the conjecture that the best possible decay was obtained for constant damping.
Bulge Exchanges in Algorithms of QR Type
Authors: David S. Watkins
Venue: SIAM Journal on Matrix Analysis and Applications (1998)

The QR algorithm and its variants are among the most popular methods for calculating eigenvalues of matrices. Typical implementations chase bulges from top to bottom of an upper Hessenberg matrix. It is also possible to chase bulges from bottom to top. There are some situations in which it may be advantageous to chase bulges in both directions at once, in which case one needs a procedure for passing bulges through each other without mixing up the information that the bulges convey. This paper derives a procedure for passing bulges of arbitrary degree through each other. Experiments with a Fortran 90 program show that the procedure works well in practice for bulges of degree two.
Boundary Controllability of Thermoelastic Plates via the Free Boundary Conditions
Authors: George Avalos, Irena Lasiecka
Venue: SIAM Journal on Control and Optimization (2000)

Controllability properties of a partial differential equation (PDE) model describing a thermoelastic plate are studied. The PDE is composed of a Kirchoff plate equation coupled to a heat equation on a bounded domain, with the coupling taking place on the interior and boundary of the domain. The coupling in this PDE is parameterized by $\alpha >0$. Boundary control is exerted through the (two) free boundary conditions of the plate equation and through the Robin boundary condition of the temperature. These controls have the physical interpretation of inserted forces and moments and prescribed temperature, respectively, all of which act on the edges of the plate. The main result here is that under such boundary control, and with initial data in the basic space of well-posedness, one can simultaneously control the displacement of the plate exactly and the temperature approximately. Moreover, the thermal control may be taken to be arbitrarily smooth in time and space, and the thermal control region may be any nonempty subset of the boundary. This controllability holds for arbitrary values of the coupling parameter $\alpha $, with the optimal controllability time in line with that seen for uncoupled Kirchoff plates.
Readability and computer documentation
Authors: Gretchen Hargis
Venue: ACM Journal of Computer Documentation (JCD) (2000)

Traditional readability concerns are alive and well, but subsumed within several more recent documentation quality efforts. For example, concerns with interestingness and translatability for global markets, with audience analysis and task sufficiency, and with reader appropriateness of technical text all involve readability, but often in ways not easily measured by any formula.
Power consumption reduction in high-speed &Sigma;&Delta; bandpass modulators
Authors: P. Cusinato, F. Stefani, A. Baschirotto
Venue: Proceedings of the 2000 international symposium on Low power electronics and design (2000)

Power consumption is a key point in the design of high-speed switched capacitor (SC) circuits, which allow to efficiently implement a number of analog functions. Among them, SC &Sgr;&Dgr; modulators are very popular for A/D conversion: in this kind of circuits, operational amplifiers are the most consuming cells because of their requirements in terms of DC gain and unity-gain frequency. A new amplifier with 110dB DC gain and a unity-gain frequency of 250MHz is presented. The large power consumption (20mW) makes critical its use in commercial applications: however, combining this cell with a fast adaptive biasing circuit, high performance may be achieved with a reasonable dissipation.This approach has been used in the design of a 6th-order bandpass &Sgr;&Dgr; modulator featuring 73dB DR and suitable for the conversion at IF (10.7MHz) of the FM radio signal.
Heuristic tradeoffs between latency and energy consumption in register assignment
Authors: R. Anand, M. Jacome, G. de Veciana
Venue: Proceedings of the eighth international workshop on Hardware/software codesign (2000)

One of the challenging tasks in code generation for embedded systems is register allocation and assignment, wherein one decides on the placement and lifetimes of variables in registers. When there are more live variables than registers, some variables need to be spilled to memory and restored later. In this paper we propose a policy that minimizes the number of spills &mdash; which is critical for portable embedded systems since it leads to a decrease in energy consumption. We argue however, that schedules with a minimal number of spills do not necessarily have minimum latency. Accordingly, we propose a class of policies that explore tradeoffs between assignments leading to schedules with low latency versus those leading to low energy consumption and show how to tune them to particular datapath characteristics. Based on experimental results we propose a criterion to select a register assignment policy that for 99% of the cases we considered minimizes both latency and energy consumption associated with spills to memory.
The practical management of information ethics problems: test your appropriate use policy, part III
Authors: John Smith
Venue: ACM SIGUCCS Newsletter (1998)

In Part II of this series, I pointed out that much of our appropriate use policy is rooted in mainframe technology, where there is clear delineation between the authority and responsibility of the institution and that of the user. In this article I would like to explore some of the ethical implications of a truly distributed computing environment - one where responsibility, authority, and management is distributed, as well as the physical components.
A New Way to Represent the Relative Position between Areal Objects
Authors: Pascal Matsakis, Laurent Wendling
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1999)

The fuzzy qualitative evaluation of directional spatial relationships (such as ¿to the right of,¿¿to the south of$\ldots$,¿) between areal objects often relies on the computation of a histogram of angles, which is considered to provide a good representation of the relative position of an object with regard to another. In this paper, the notion of the histogram of forces is introduced. It generalizes and may supersede the histogram of angles. The objects (2D entities) are handled as longitudinal sections (1D entities), not as points (0D entities). It is thus possible to fully benefit from the power of integral calculus and, so, ensure rapid processing of raster data, as well as of vector data, explicitly considering both angular and metric information.
The Effect of Property Rights and Audit Information Quality on Team Incentives for Inventory Reduction
Authors: Ramji Balakrishnan, Nandu J. Nagarajan, K. Sivaramakrishnan
Venue: Management Science (1998)

We analyze how limited contractibility and the informational quality of audits affect inventory levels and the optimality of individual versus team-based production. We use a two-period agency model in which contractibility is limited and agents meet a fixed delivery quota each period. A costly audit is triggered in any period if the delivery quota of output for the period is not met. We show that the informativeness of the audit plays a crucial role in resolving coordination problems between agents when they are organized as a team. When the audit is perfectly informative about agent productivity and inventory levels, team-based production is optimal. The team meets its quota even though, in equilibrium, the audit never takes place. If the audit is not perfectly informative about inventory levels, we show that team-based production typically induces agents to endogenously reduce inventory levels and could even result in agents adopting a zero-inventory policy. When the audit is completely uninformative, individual production is superior to team-based production.
An introduction to WAN analysis and the HCT-6000 protocol analyser
Authors: Terry Watson
Venue: International Journal of Network Management (1999)

This article describes the use of a Wide Area Network Protocol Analyser, the HCT-6000, in examining a serial kilostream link running the Point to Point Protocol. The various test facilities the unit offers are explored and an overview of the PPP protocol is given. Copyright &copy; 1999 John Wiley Sons, Ltd.
Terabit burst switching
Authors: Jonathan S. Turner
Venue: Journal of High Speed Networks (1999)

Demand for network bandwidth is growing at unprecedented rates, placing growing demands on switching and transmission technologies. Wavelength division multiplexing will soon make it possible to combine hundreds of gigabit channels on a single fiber. This paper presents an architecture for Burst Switching Systems designed to switch data among WDM links, treating each link as a shared resource rather than just a collection of independent channels. The proposed network architecture separates burst level data and control, allowing major simplifications in the data path in order to facilitate all-optical implementations. To handle short data bursts efficiently, the burst level control mechanisms in burst switching systems must keep track of future resource availability when assigning arriving data bursts to channels or storage locations. The resulting Lookahead Resource Management problems raise new issues and require the invention of completely new types of high speed control mechanisms. This paper introduces these problems and describes approaches to burst level resource management that attempt to strike an appropriate balance between high speed operation and efficiency of resource usage.
A functional model of cooperative system management
Authors: Bharat Bhushan Ahmed Patel
Venue: International Journal of Network Management (1998)

There is a need for information exchange and communication between management applications that are distributed over a large system. In this situation, a fundamental problem is how the management systems should cooperate in order to achieve overall management of a system. In order to address this problem, this article presents a functional model of cooperative system management. &copy; 1998 John Wiley & Sons, Ltd.
Testing pointing device performance and user assessment with the ISO 9241, Part 9 standard
Authors: Sarah A. Douglas, Arthur E. Kirkpatrick, I. Scott MacKenzie
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: the CHI is the limit (1999)

The IS0 9241, Part 9 Draft International Standard for testing computer pointing devices proposes an evaluation of performance and comfort. In this paper we evaluate the scientific validity and practicality of these dimensions for two pointing devices for laptop computers, a finger-controlled isometric joystick and a touchpad. Using a between-subjects design, evaluation of performance using the measure of throughput was done for one-direction and multi-directional pointing and selecting. Results show a significant difference in throughput for the multi-directional task, with the joystick 27% higher; results for the one-direction task were non-significant. After the experiment, participants rated the device for comfort, including operation, fatigue, and usability. The questionnaire showed no overall difference in the responses, and a significant statistical difference in only the question concerning force required to operate the device - the joystick requiring slightly more force. The paper concludes with a discussion of problems in implementing the IS0 standard and recommendations for improvement.
Small Min-Cut Polyhedra
Authors: Ramesh Bollapragada, Uday Rao, Dimitris Alevras
Venue: Mathematics of Operations Research (1999)

We study small min-cut polyhedra for directed and undirected complete graphs. We give the ideal descriptions of the polyhedra for undirected graphs with up to seven nodes and for directed graphs with up to five nodes, and generalize the inequalities for complete graphs with arbitrary number of nodes. The facial structure of the polyhedra turns out to be unexpectedly rich.
Quality is in the eye of the beholder: meeting users' requirements for Internet quality of service
Authors: Anna Bouch, Allan Kuchinsky, Nina Bhatti
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2000)

Growing usage and diversity of applications on the Internet makes Quality of Service (QoS) increasingly critical [15]. To date, the majority of research on QoS is systems oriented, focusing on traffic analysis, scheduling, and routing. Relatively minor attention has been paid to user-level QoS issues. It is not yet known how objective system quality relates to users' subjective perceptions of quality. This paper presents the results of quantitative experiments that establish a mapping between objective and perceived QoS in the context of Internet commerce. We also conducted focus groups to determine how contextual factors influence users' perceptions of QoS. We show that, while users' perceptions of World Wide Web QoS are influenced by a number of contextual factors, it is possible to correlate objective measures of QoS with subjective judgements made by users, and therefore influence system design. We argue that only by integrating users' requirements for QoS into system design can the utility of the future Internet be maximized.
Impact of Information Systems on Acute Care Hospitals: Results from a Survey in the United States
Authors: Myron Hatcher
Venue: Journal of Medical Systems (1998)

These results are from a survey of acute care hospitals in the United States. A random sample of 813 hospitals was selected with 115 responding and 33 incorrect addresses resulting in a 15% response rate. The purpose of the study was to measure the impact and future potential of information systems integration in the financial, medical, and administrative systems of the hospitals. Impact of Information Systems is measured in many ways. Questions about employee moral, reductions in employees, goals being met and overall satisfaction with the systems are asked and results analyzed. This information will provide a benchmark for hospitals to determine their information systems position and technology transfer planning. These analyses will lead to setting goals.
Nonlinear Versus Linear Learning Devices: A Procedural Perspective
Authors: Emilio Barucci, Leonardo Landi
Venue: Computational Economics (1998)

We provide a discussion of bounded rationality learning behind traditional learning mechanisms, i.e., Recursive Ordinary Least Squares and Bayesian Learning . These mechanisms lack for many reasons a behavioral interpretation and, following the Simon criticism, they appear to be &rsquo;substantively rational&lsquo;. In this paper, analyzing the Cagan model, we explore two learning mechanisms which appear to be more plausible from a behavioral point of view and somehow &rsquo;procedurally rational&lsquo;: Least Mean Squares learning for linear models and Back Propagation for Artificial Neural Networks . The two algorithms look for a minimum of the variance of the error forecasting by means of a steepest descent gradient procedure. The analysis of the Cagan model shows an interesting result: non-convergence of learning to the Rational Expectations Equilibrium is not due to the restriction to linear learning devices; also Back Propagation learning for Artificial Neural Networks may fail to converge to the Rational Expectations Equilibrium of the model.