ppxscal/embedding_network huggingface dataset:
A Multi-Agent System for Distributed Information Retrieval on the World Wide Web
Authors: Keith L. Clark, Vasilios S. Lazarou
Venue: Proceedings of the 6th Workshop on Enabling Technologies on Infrastructure for Collaborative Enterprises (1997)

In this paper a novel approach concerned with the general framework of Information Management, is presented. We use a Multi-Agent System to cope with the problem of Distributed Information Retrieval. The Distributed Information Retrieval task deals with the collection of information from multiple and usually heterogeneous information sources that exist in a distributed environment, which in our case is the World Wide Web.
A new sequence related Smarandache sequences and its mean value formula
Authors: Zhang Wenpeng
Venue: Smarandache Notions Journal (2002)

Let n be any positive integer, a(n) denotes the product of all non-zero digits in base 10. For natural x ≥ 2 and arbitrary fixed exponent m ∈ N, let Am(x) = Σn > x am(n). The main purpose of this paper is to give two exact calculating formulas for A1(x) and A2(x).
Central Limit Theorems for Permuted Regenerative Estimators
Authors: James M. Calvin, Marvin K. Nakayama
Venue: Operations Research (2000)

We prove strong laws of large numbers and central limit theorems for some permuted estimators from regenerative simulations. These limit theorems provide the basis for constructing asymptotically valid confidence intervals for the permuted estimators.
Work tasks and socio-cognitive relevance: A specific example
Authors: Birger Hjørland, Frank Sejer Christensen
Venue: Journal of the American Society for Information Science and Technology (2002)

This article presents a concrete example of a work task: a doctor treating a patient suffering from schizophrenia. It is outlined how work task, work situation, perceived work situation, task complexity, information need, information seeking and topicality, situational relevance, relevance assessment (including a discussion of system relevance end algorithmic relevance) and work task fulfillment may be understood. Relevance is defined as something serving as a tool to a goal. "Tool" understood in the widest possible sense, including ideas, meanings, theories and documents as tools.
The role of Jacobi polynomials in the theory of Hermite and Laguerre 2D polynomials
Authors: A. Wünsche
Venue: Journal of Computational and Applied Mathematics (2003)

Using an alternative definition of usual Hermite polynomials, two problems in the theory of general Hermite and Laguerre 2D polynomials can be separated with advantage for the further treatment: the introduction of a general 2D matrix in the linear transformation of powers of the components of a 2D vector and the generation of Hermite (or Laguerre) polynomials by applying an integral operator to these powers. The Jacobi polynomials appear in the finite-dimensional irreducible representations of the two-dimensional general linear group GL(2, C).
Rendezvous Search: A Personal Perspective
Authors: Steve Alpern
Venue: Operations Research (2002)

The rendezvous-search problem was posed by the author 25years ago. In its basic form, it asks how two unit speed players can find each other in least expected time, when randomly placed in a known dark region. The problem received little attention until about 10 years ago. This article surveys the rapid progress that has been made since then, and also presents some new results.
A New Exact Penalty Function
Authors: Waltraud Huyer, Arnold Neumaier
Venue: SIAM Journal on Optimization (2002)

For constrained smooth or nonsmooth optimization problems, new continuously differentiable penalty functions are derived. They are proved exact in the sense that under some nondegeneracy assumption, local optimizers of a nonlinear program are precisely the optimizers of the associated penalty function. This is achieved by augmenting the dimension of the program by a variable that controls both the weight of the penalty terms and the regularization of the nonsmooth terms.
Advanced visualization technology for terascale particle accelerator simulations
Authors: Kwan-Liu Ma, Greg Schussman, Brett Wilson, Kwok Ko, Ji Qiang, Robert Ryne
Venue: Proceedings of the 2002 ACM/IEEE conference on Supercomputing (2002)

This paper presents two new hardware-assisted rendering techniques developed for interactive visualization of the terascale data generated from numerical modeling of next-generation accelerator designs. The first technique, based on a hybrid rendering approach, makes possible interactive exploration of large-scale particle data from particle beam dynamics modeling. The second technique, based on a compact texture-enhanced representation, exploits the advanced features of commodity graphics cards to achieve perceptually effective visualization of the very dense and complex electromagnetic fields produced from the modeling of reflection and transmission properties of open structures in an accelerator design. Because of the collaborative nature of the overall accelerator modeling project, the visualization technology developed is for both desktop and remote visualization settings. We have tested the techniques using both time-varying particle data sets containing up to one billion particles per time step and electromagnetic field data sets with millions of mesh elements.
Comparison of interval methods for plotting algebraic curves
Authors: Ralph Martin, Huahao Shou, Irina Voiculescu, Adrian Bowyer, Guojin Wang
Venue: Computer Aided Geometric Design (2002)

This paper compares the performance and efficiency of different function range interval methods for plotting f(x, y)=0 on a rectangular region based on a subdivision scheme, where f(x, y) is a polynomial. The solution of this problem has many applications in CAGD. The methods considered are interval arithmetic methods (using the power basis, Bernstein basis, Homer form and centred form), an affine arithmetic method, a Bernstein coefficient method, Taubin's method, Rivlin's method, Gopalsamy's method, and related methods which also take into account derivative information. Our experimental results show that the affine arithmetic method, interval arithmetic using the centred form, the Bernstein coefficient method, Taubin's method, Rivlin's method, and their related derivative methods have similar performance, and generally they are more accurate and efficient than Gopalsamy's method and interval arithmetic using the power basis, the Bernstein basis, and Horner form methods.
An algorithm to estimate time-varying parameter SURE models under different types of restriction
Authors: Susan Orbe, Eva Ferreira, Juan Rodriguez-Poo
Venue: Computational Statistics Data Analysis (2003)

A nonparametric method to estimate time-varying coefficients in seemingly unrelated regression equations models is proposed. The procedure presents two main advantages with respect to other proposals in literature. First, it allows to incorporate both cross and time-varying restrictions into the parameters. Second, the estimator is obtained in a closed form, and there is no need of an iterative method to compute its value. However, this computation requires to solve a linear system where the number of equations and coefficients increases with the sample size. This problem is overcome by using an algorithm that reduces the computation cost. The algorithm enables to solve the linear system in a recursive manner where (in each step) a lower dimensional linear system is solved and there is no increase with sample size.
Parallel Computation of the Euclidean Distance Transform on a Three-Dimensional Image Array
Authors: Yu-Hua Lee, Shi-Jinn Horng, Jennifer Seitzer
Venue: IEEE Transactions on Parallel and Distributed Systems (2003)

In a two- or three-dimensional image array, the computation of Euclidean distance transform (EDT) is an important task. With the increasing application of 3D voxel images, it is useful to consider the distance transform of a 3D digital image array. Because the EDT computation is a global operation, it is prohibitively time consuming when performing the EDT for image processing. In order to provide the efficient transform computations, parallelism is employed. In this paper, we first derive several important geometry relations and properties among parallel planes. We then, develop a parallel algorithm for the three-dimensional Euclidean distance transform (3D_EDT) on the EREW PRAM computation model. The time complexity of our parallel algorithm isO(\log^2 N)for anN \times N \times Nimage array and this is currently the best known result. A generalized parallel algorithm for the 3D-EDT is also proposed. We implement the proposed algorithms sequentially, the performance of which exceeds the existing algorithms (proposed by Yamada, Toriwaki). Finally, we develop the corresponding parallel programs on both the emulated EREW PRAM model computer and the IBM SP2 to verify the speed-up properties of the proposed algorithms.
One-class texture classifier in the CCR feature space
Authors: Raúl E. Sánchez-Yáñez, Evguenii V. Kurmyshev, Antonio Fernández
Venue: Pattern Recognition Letters (2003)

A one-class classifier in the coordinated clusters representation (CCR) feature space is proposed in order to form classes with a required homogeneity with respect to given features of texture images. Experiments with gray level texture images of Brodatz catalog and "Rosa Porriño" polished granites demonstrate high discrimination performance of the criterion. The compactness of a class of images in the CCR feature space is determined by the class variance and, in addition, controlled by an empirical adjustment parameter.
Some derivatives of Newton's method
Authors: J. B. Thoo
Venue: PRIMUS: problems, resources, and issues in mathematics undergraduate studies (2002)

Every first-year calculus student learns Newton's method as part of a repertoire of numerical root-finding methods. We present two other numerical root-finding methods that we derive using Newton's method: a simplified Newton's method, and Halley's method. These two methods are not new, yet they seldom find their way into a first calculus course even though they would not be out of place in such a course.
Automatic assignment management and peer evaluation
Authors: A. Trivedi, Dulal C. Kar, Holly Patterson-McNeill
Venue: Journal of Computing Sciences in Colleges (2003)

Students in programming courses can learn from peer evaluation of their work. Also a student can learn by evaluating other students' works and can find many useful techniques in them to improve his/her programming skill. There are many tools available for online course management. However, none of them fully supports anonymous peer evaluation of assignments. In this work, we present a Web-based system that can be used to manage peer evaluation of assignments electronically and anonymously. The peer evaluation of an assignment is guided with a rubric designed and maintained by an instructor. The system has been developed by making use of free distribution of software products available for the public. Such a system can improve the quality of teaching in many computing courses, including all programming courses.
New Lower Bound Techniques for Dynamic Partial Sums and Related Problems
Authors: Thore Husfeldt, Theis Rauhe
Venue: SIAM Journal on Computing (2003)

We study the complexity of the dynamic partial sum problem in the cell-probe model. We give the model access to nondeterministic queries and prove that the problem remains hard. We give the model access to the right answer $\pm 1$ as an oracle and prove that the problem remains hard. This suggests which kind of information is hard to maintain. From these results, we derive a number of lower bounds for dynamic algorithms and data structures: We prove lower bounds for dynamic algorithms for existential range queries, reachability in directed graphs, planarity testing, planar point location, incremental parsing, and fundamental data structure problems like maintaining the majority of the prefixes of a string of bits. We prove a lower bound for reachability in grid graphs in terms of the graph's width. We characterize the complexity of maintaining the value of any symmetric function on the prefixes of a bit string.
Approximation of weak-to-norm continuous mappings
Authors: Lorenzo D'Ambrosio
Venue: Journal of Approximation Theory (2002)

The purpose of this paper is to study the approximation of vector-valued mappings defined on a subset of a normed space. We investigate Korovkin-type conditions useful to recognize if a given sequence of linear operators is a so-called approximation process. First, we give a sufficient condition for this sequence to approximate the class of bounded, uniformly continuous functions. Then we present some sufficient and necessary conditions guaranteeing the approximation within the class of unbounded, *weak-to-norm continuous mappings. We also derive some estimates of the rate of convergence. We apply concrete approximation processes to derive representation formulae for semigroups of bounded linear operators.
Algorithms for Path-Based Placement of Inspection Stations on Networks
Authors: Daniel J. Rosenkrantz, Giri K. Tayi, S. S. Ravi
Venue: INFORMS Journal on Computing (2000)

Placement of inspection stations is a common task in transportation and communication networks. In this paper, two categories of problems involving placement of inspection stations are studied. The first category deals with the selection of inspection stations along a given path from an origin to a destination. The second considers simultaneous selection of both a path and inspection stations along that path. We formulate these problems under a variety of minimization objectives such as the maximum gap between two consecutive inspection stations, the expected penalty cost of failure along the path, and the total inspection cost. Our results include efficient algorithms for many formulations and complexity results as well as fully polynomial approximation schemes for other formulations. When considering cost objectives, we identify a core problem and show that the complexity of many formulations is directly related to the complexity of the core problem.
Minimizing Service and Operation Costs of Periodic Scheduling
Authors: Amotz Bar-Noy, Randeep Bhatia, Joseph (Seffi) Naor, Baruch Schieber
Venue: Mathematics of Operations Research (2002)

We study the problem of scheduling activities of several types under the constraint that, at most, a fixed number of activities can be scheduled in any single time slot. Any given activity type is associated with a service cost and an operating cost that increases linearly with the number of time slots since the last service of this type. The problem is to find an optimal schedule that minimizes the long-run average cost per time slot. Applications of such a model are the scheduling of maintenance service to machines, multi-item replenishment of stock, and minimizing the mean response time inBroadcast Disks. Broadcast Disks recently gained a lot of attention because they were used to model backbone communications in wireless systems, Teletext systems, and Web caching in satellite systems.The first contribution of this paper is the definition of a general model that combines into one several important previous models. We prove that an optimalcyclic schedule for the general problem exists, and we establish the NP-hardness of the problem. Next, we formulate a nonlinear program that relaxes the optimal schedule and serves as a lower bound on the cost of an optimal schedule. We present an efficient algorithm for finding a near-optimal solution to the nonlinear program. We use this solution to obtain several approximation algorithms.(1) A 9/8 approximation for a variant of the problem that models the Broadcast Disks application. The algorithm uses some properties of "Fibonacci sequences." Using this sequence, we present a 1.57-approximation algorithm for the general problem. (2) A simple randomized algorithm and a simple deterministic greedy algorithm for the problem. We prove that both achieve approximation factor of 2. To the best of our knowledge this is the first worst-case analysis of a widely used greedy heuristic for this problem.
Moving mesh finite element methods based on harmonic maps
Authors: Ruo Li, Wenbin Liu, Tao Tang, Pingwen Zhang
Venue: Scientific computing and applications (2001)

This paper is devoted to the applications of a class of moving mesh finite element methods based on harmonic maps. We review some recent work of the authors on solving PDES, variational inequalities and optimal control problems by use of the moving mesh techniques.
A 5.8-GHz Quadrature Cross-Coupled Oscillator
Authors: Jorge R. Fernandes, Michiel H. L. Kouwenhoven, Chris Van Den Bos, Koen Van Hartingsveldt, Chris Verhoeven
Venue: Analog Integrated Circuits and Signal Processing (2003)

This paper describes the implementation of a quadrature cross-coupled relaxation oscillator to be used in an OFDM RF front-end transceiver. A prototype of the oscillator was realized in a SiGe BiCMOS technology, and an oscillation frequency of 5.8 GHz was obtained which is 1/6 of the maximum fT of the bipolar transistors. The circuit performance is evaluated by simulation and by experiment.
When Market Information Constitutes Fields: Sensemaking of Markets in the Commercial Music Industry
Authors: N. Anand, Richard A. Peterson
Venue: Organization Science (2000)

In this paper we outline a key mechanism through which organizational fields are constituted. We suggest that in competitive fields, the market serves as a magnet around which groups of actors consolidate, and that cognition of markets occurs through the creation, distribution, and interpretation of a web of information about the "market." To illustrate our theory, we present a case study of theBillboard music chart from the commercial music industry to show that changes in either scope, methodology, or political tone with which market information is presented can provide a major jolt to the participants' understanding of their field.
Centralized broadcast in multihop radio networks
Authors: Iris Gaber, Yishay Mansour
Venue: Journal of Algorithms (2003)

We show that for any radio network there exists a schedule of a broadcast whose time is O (D +log5 n), where D is the diameter and n is the number of nodes. (This result implies an optimal broadcast to networks with D =Ω(log5 n).) We present a centralized randomized polynomial time algorithm that given a network and a source, outputs a schedule for broadcasting the message from the source to the rest of the network.
Using modern graphics architectures for general-purpose computing: a framework and analysis
Authors: Chris J. Thompson, Sahngyun Hahn, Mark Oskin
Venue: Proceedings of the 35th annual ACM/IEEE international symposium on Microarchitecture (2002)

Recently, graphics hardware architectures have begun to emphasize versatility, offering rich new ways to programmatically reconfigure the graphics pipeline. In this paper, we explore whether current graphics architectures can be applied to problems where general-purpose vector processors might traditionally be used. We develop a programming framework and apply it to a variety of problems, including matrix multiplication and 3-SAT. Comparing the speed of our graphics card implementations to standard CPU implementations, we demonstrate startling performance improvements in many cases, as well as room for improvement in others. We analyze the bottlenecks and propose minor extensions to current graphics architectures which would improve their effectiveness for solving general-purpose problems. Based on our results and current trends in microarchitecture, we believe that efficient use of graphics hardware will become increasingly important to high-performance computing on commodity hardware.
Some monotonicity results on the zeros of the generalized Laguerre polynomials
Authors: Pierpaolo Natalini, Biagio Palumbo
Venue: Journal of Computational and Applied Mathematics (2003)

Some monotonicity results for the function f(α)xn,k(α), where xn,k(α) is the kth zero of generalized Laguerre polynomial Ln(α)(x) and f(α) is a suitable function of α, are derived by means of the classical method of Stiltjes.
Optimal Placement of Add/Drop Multiplexers: Heuristic and Exact Algorithms
Authors: Alain Sutter, Francois Vanderbeck, Laurence Wolsey
Venue: Operations Research (1998)

We study a problem that has arisen recently in the design of telecommunications transmission networks at France Telecom. Given a set of centers in a city or conglomeration linked together on a ring architecture, given the expected demands between the centers and an essentially unlimited availability of rings of fixed capacity on the network, assign demand pairs and corresponding add/drop multiplexers to the rings so as to satisfy the demands and minimize the number of "costly" multiplexers installed. Heuristics based on simulated annealing have been developed for the basic problem and several variants. France Telecom is particularly interested in validating the effectiveness of the heuristics. An exact algorithm based on integer column generation is shown to provide tight performance guarantees, and in most cases to give provable minimum cost solutions. Column generation is used even though the subproblems are strongly NP-hard and are solved by standard mixed integer programming software. In addition, the Master Problems involve both integer columns and integer variables, whereas these are 0-1 in most reported applications.
Smarandache semirings and semifields
Authors: W. B. Vasantha Kandasamy
Venue: Smarandache notions (2002)

In this paper we study the notions of Smarandache semirings and semifields and obtain some interesting results about them. We show that not every semiring is a Smarandache semiring. We similarly prove that not every semifield is a Smarandache semifield. We give several examples to make the concept lucid. Further, we propose an open problem about the existence of Smarandache semiring S of finite order.
Real-time haptic and visual simulation of bone dissection
Authors: Marco Agus, Andrea Giachetti, Enrico Gobbetti, Gianluigi Zanetti, Antonio Zorcolo
Venue: Presence: Teleoperators and Virtual Environments (2003)

Bone dissection is an important component of many surgical procedures. In this paper, we discuss a haptic and visual simulation of a bone-cutting burr that is being developed as a component of a training system for temporal bone surgery. We use a physically motivated model to describe the burr-bone interaction, which includes haptic forces evaluation, the bone erosion process, and the resulting debris. The current implementation, directly operating on a voxel discretization of patient-specific 3D CT and MR imaging data, is efficient enough to provide real-time feedback on a low-end multiprocessing PC platform.
Constructing consistent fuzzy surfaces from fuzzy data
Authors: Weldon A. Lodwick, Jorge Santos
Venue: Fuzzy Sets and Systems (2003)

Given fuzzy data describing a three-dimensional entity such as terrain, we develop methods to construct surfaces that are consistent with the uncertainty in the data and surface model itself. In particular, surfaces generated from higher α-cut values of the fuzzy data are contained within the surfaces generated by lower α-cut values of the fuzzy data. Moreover, the smoothness and continuity conditions of the surface generating method is maintained by each level surface. We demonstrate the ideas by developing two- and three-dimensional surfaces from fuzzy data for cubic splines and digital terrain models generated from triangulation.