ppxscal/embedding_network huggingface dataset:
Development of a Public Key Infrastructure across Multiple Enterprises
Authors: B. J. Desind, T. M. Sharick, J. P. Long, B. J. Wood
Venue: Proceedings of the 6th Workshop on Enabling Technologies on Infrastructure for Collaborative Enterprises (1997)

Main-stream applications are beginning to incorporate public key cryptography. It can be difficult to deploy this technology without a robust infrastructure to support it. It can also be difficult to deploy a public key infra-structure among multiple enterprises when different applications and standards must be supported. This discussion chronicles the efforts by a team within the US Department of EnergyÆs Nuclear Weapons Complex to build a public key infrastructure and deploy applications that use it. The emphasis of this talk will be on the lessons learned during this effort and an assessment of the overall impact of this technology.
Variants of iterative learning
Authors: Steffen Lange, Gunter Grieser
Venue: Theoretical Computer Science (2003)

We investigate the principal learning capabilities of iterative learners in some more details. Thereby, we confine ourselves to study the learnability of indexable concept classes. The general scenario of iterative learning is as follows. An iterative learner successively takes as input one element of a text (an informant) for a target concept as well as its previously made hypothesis and outputs a new hypothesis about the target concept. The sequence of hypotheses has to converge to a hypothesis correctly describing the target concept.We study two variants of this basic scenario and compare the learning capabilities of all resulting models of iterative learning to one another as well to the standard learning models finite inference, conservative identification, and learning in the limit.First, we consider the case that an iterative learner has to learn from fat texts (fat informants), only. In this setting, it is guaranteed that relevant information is, in principle, accessible at any time in the learning process. Second, we study a variant of iterative learning, where an iterative learner is supposed to learn no matter which initial hypothesis is actually chosen. This variant is suited to describe scenarios that are typical for case-based reasoning.
A fundamental solution method for the reduced wave problem in a domain exterior to a disc
Authors: Teruo Ushijima, Fumihiro Chiba
Venue: Journal of Computational and Applied Mathematics (2003)

The aim of the present paper is to establish unique solvability theorems for approximate problems derived by fundamental solution method applied to the Dirichlet boundary value problem of the two-dimensional reduced wave equation in the exterior region of a disc.
Efficient visibility queries in simple polygons
Authors: Prosenjit Bose, Anna Lubiw, J. Ian Munro
Venue: Computational Geometry: Theory and Applications (2002)

We present a method of decomposing a simple polygon that allows the preprocessing of the polygon to efficiently answer visibility queries of various forms in an output sensitive manner. Using O(n3 log n) preprocessing time and O(n3) space, we can, given a query point q inside or outside an n vertex polygon, recover the visibility polygon of q in O(log n + k) time, where k is the size of the visibility polygon, and recover the number of vertices visible from q in O(log n) time.The key notion behind the decomposition is the succinct representation of visibility regions, and tight bounds on the number of such regions. These techniques are extended to handle other types of queries, such as visibility of fixed points other than the polygon vertices, and for visibility from a line segment rather than a point. Some of these results have been obtained independently by Guibas, Motwani and Raghavan [18].
On the Gröbner bases of some symmetric systems and their application to coding theory
Authors: Teo Mora, Massimiliano Sala
Venue: Journal of Symbolic Computation (2003)

The Gröbner bases of the ideal generated by the symmetric functions are presented. Moreover we show how they can be fruitfully applied to a problem arising from coding theory.
Developing an airline freight management system: meeting airline and end-user challenges
Authors: Sam J. Racine, John P. Curtin
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

A commercial freight management application for airlines must address the business concerns of airlines as well as offer limited job interference for end-users whose primary occupation is to move cargo. Discussion includes usability challenges and interactive design solutions, methodology for quick development in a time- and resource-constrained budget, and compromises required for commercial success.
Judgmental Errors, Interactive Norms, and the Difficulty of Detecting Strategic Surprises
Authors: Joseph Lampel, Zur Shapira
Venue: Organization Science (2001)

The concept of strategic surprise has been used by writers on military strategy to explore the successful amplification of resources during battle. This paper applies the same concept to subcontracting relationships and develops a cognitive framework to explain the phenomenon of strategic surprises, using buyer-supplier relations as an example. We first examine the factors that produce vulnerability to strategic surprise in cooperative situations. Then, we explore the reasons why firms are caught by surprise in spite of their vigilance. We present a model representing false alarms and strategic surprises as judgmental errors. We argue that judgmental errors cause misinterpretation of evidence and a consequent sense of false security. Interactive norms, which exist in some industries and may be taken as proxies for enduring relationships, may increase the likelihood of misjudgment and strategic surprises.
Parallel simulation of traffic in Geneva using cellular automata
Authors: Alexandre Dupuis, Bastien Chopard
Venue: Virtual shared memory for distributed architectures (2001)

Road traffic microsimulations based on the individual motion of all vehicles are now recognized as an important tool to describe, understand and manage road traffic. Cellular automata models are a very efficient way to implement car motion. This paper presents a detailed description of a parallel cellular automata traffic microsimulator. We discuss the data structure, domain decomposition, and provide a detailed performance analysis for a problem of size n on p processors. We consider realistic simulation for the city of Geneva and report some results concerning the global traffic behavior. Provided that enough processors are used, large scale simulation can be performed in less time than the real process.
Identifying the difficulties of object-oriented development
Authors: Steven D. Sheetz
Venue: Journal of Systems and Software (2002)

Identifying the perceptions of developers that use object-oriented (OO) system development techniques is necessary to understand why they are described as difficult to learn and use. Professional developers with a broad range of experience were asked to share their perceptions of the issues that contribute to the difficulties of using OO techniques. The 67 developers primarily were from the tele-communications and systems consulting industries in a large metropolitan area. Seventeen small groups of developers with similar levels of experience completed a 2.5-h group cognitive mapping process using a group support system (GSS). Each GSS session consisted of activities to identify difficult issues, define categories that classify the issues by similarity, rate the importance of the categories for causing difficulties, and identify causal relationships among the categories to form a cognitive map that represents the group's shared perceptions of the difficulties of using OO techniques. The 1279 issues identified were organized into 141 categories by the 17 groups. These 141 group-generated categories were merged to identify a set of 9 overall categories to allow comparisons of perceptions across groups and levels of experience. The results reveal a common "core" of difficult issues associated with using OO techniques that was shared by novices, intermediates, and experts. Overall category group cognitive maps reveal substantial differences in the causal relationships perceived by novices and experts.
Parallel motion computing on the MasPar MP-2 machine
Authors: A. Branca, A. Distante, Henry Ellingworth
Venue: Proceedings of the 9th International Symposium on Parallel Processing (1995)

Past research has shown that qualitative information about visual motion can be recovered by analyzing the optical flow-the 2D projection on the image plane of the 3D instantaneous velocities of points lying on visible moving surfaces in a dynamic scene. The main problem in calculating the optical flow is the expensive computational time. One approach to optical flow calculations in real time is to use parallel computers. We describe how the well known technique proposed by Horn and Schunck (1981) to compute the optical flow con be implemented on a SIMD machine such as the MasPar. We describe some experimental tests to show how, with a such machine, it is possible to obtain real-time speeds in optical flow computation.
Local internal controllability of the Boussinesq system
Authors: Lijuan Wang, Gengsheng Wang
Venue: Nonlinear Analysis: Theory, Methods Applications (2003)

In this paper, we shall show that the H3 × H3 steady-state solutions to Boussinesq equations in n-dimensional bounded domain Ω, n = 2, 3, are locally controllable by internal controllers with the support in subsets ω ⊂ Ω.
Operations Research at Bell Laboratories through the 1970s: Part III
Authors: Cree S. Dawson, Charles J. Mccallum, R. Bradford Murphy, Eric Wolman
Venue: Operations Research (2000)

This historical account of operations research at Bell Laboratories was drafted in the late 1970s when the authors were part of the Operations Research Center within Bell Laboratories at AT&T; it has not previously appeared in the open literature. We have added a few references to later publications that describe particular aspects of the period covered. Discussions of technological practices and organizational arrangements expressed in the present tense represent a viewpoint of about 1980, before "divestiture" split up the Bell System. A comprehensive table of contents for parts I, II, and III can be found in the Online Collection of theOperations Research Home Page, at http://or.pubs.informs.org.
Decomposing monomial representations of solvable groups
Authors: Markus Püschel
Venue: Journal of Symbolic Computation (2002)

We present an efficient algorithm that decomposes a monomial representation of a solvable group G into its irreducible components. In contradistinction to other approaches, we also compute the decomposition matrix A in the form of a product of highly structured, sparse matrices. This factorization provides a fast algorithm for the multiplication with A. In the special case of a regular representation, we hence obtain a fast Fourier transform for G. Our algorithm is based on a constructive representation theory that we develop. The term "constructive" signifies that concrete matrix representations are considered and manipulated, rather than equivalence classes of representations as it is done in approaches that are based on characters. Thus, we present well-known theorems in a constructively refined form and derive new results on decomposition matrices of representations. Our decomposition algorithm has been implemented in the GAP share package AREP. One application of the algorithm is the automatic generation of fast algorithms for discrete linear signal transforms.
Laguerre-like inclusion method for polynomial zeros
Authors: Miodrag S. Petković
Venue: Journal of Computational and Applied Mathematics (2003)

A new method of the fourth order for the simultaneous inclusion of simple polynomial zeros is proposed. The presented method is based on the fixed point relation of Laguerre's type and realized in circular complex interval arithmetic. The established initial conditions guarantee the convergence of the considered method and the fourth order of convergence. These conditions are computationally verifiable, which is of practical importance. The presented iteration formula is suitable for the construction of modified interval methods with improved convergence rate with negligible additional operations. Convergence analysis and numerical results are given.
Cascade Graphs: Design, Analysis and Algorithms for Relational Joins
Authors: Ram D. Gopal, R. Ramesh, Stanley Zionts
Venue: INFORMS Journal on Computing (2000)

The focus of this work is on join optimization in relational database systems. The importance of join optimization is critically underscored by the high cost of relational joins and their frequent needs in traditional as well as emerging database applications. We demonstrate that the sequence in which the pages of the relations are accessed to process a join is a critical determinant of the join execution cost and an optimization of this sequence can lead to a significant improvement in performance over the traditional approaches. We initially develop three network structures to represent a join on two relations:page connectivity graph, cascade andblock tree cascade. A page connectivity graph is a bipartite representation of the set of connected pages in the two relations according to the join predicate. To reveal the structural properties of the join, the nodes of the bipartite graph are ordered into a set of levels, and the resulting isomorphic structure is termed acascade. From the cascade, a tree structure termed ablock tree cascade is derived by selectively grouping nodes at each level of the cascade intoblocks. We formulate the join as a tree traversal process, and accordingly develop efficient tree traversal algorithms. We develop a compact data structure to store the resulting access path, and provide a comprehensive analysis of the algorithms with detailed assessments of their performance. The performance evaluation demonstrates that the proposed approach can result in significant cost savings over the current join processing methods, for low to modest values of the join selectivity factor.
The uniqueness of the integrated density of states for the Schrödinger operators for the Robin boundary conditions
Authors: Takuya Mine
Venue: Publications of the Research Institute for Mathematical Sciences (2002)

The integrated density of states (IDS) for the Schrödinger operators is defined by using the eigenvalue counting function of the operator restricted to bounded regions with appropriate boundary conditions. Two sufficient conditions for the coincidence of the IDS for the Dirichlet boundary conditions and the IDS for the Robin boundary conditions are given. The proofs of some fundamental formulas, e.g. the change of variables, the chain rule and the divergence formula, for Lipschitz domains are given for the completeness.
Stochastic trapping in a solvable model of on-line independent component analysis
Authors: Magnus Rattray
Venue: Neural Computation (2002)

Previous analytical studies of on-line independent component analysis (ICA) learning rules have focused on asymptotic stability and efficiency. In practice, the transient stages of learning are often more significant in determining the success of an algorithm. This is demonstrated here with an analysis of a Hebbian ICA algorithm, which can find a small number of nongaussian components given data composed of a linear mixture of independent source signals. An idealized data model is considered in which the sources comprise a number of nongaussian and gaussian sources, and a solution to the dynamics is obtained in the limit where the number of gaussian sources is infinite. Previous stability results are confirmed by expanding around optimal fixed points, where a closed-form solution to the learning dynamics is obtained. However, stochastic effects are shown to stabilize otherwise unstable suboptimal fixed points. Conditions required to destabilize one such fixed point are obtained for the case of a single nongaussian component, indicating that the initial learning rate η required to escape successfully is very low (η = O(N-2) where N is the data dimension), resulting in very slow learning typically requiring O(N3) iterations. Simulations confirm that this picture holds for a finite system.
The effect of heat convection on drying of porous semi-infinite space with a heat flux condition on the fixed face x = 0
Authors: M. F. Natale, E. A. Santillan Marcus
Venue: Applied Mathematics and Computation (2003)

An analytic study is presented for rate processes, including change of phase for a semi-infinite porous substance exposed to a heat flux condition at x = 0 of the type -q0/√t, q0 > 0. Taking into account an inequality for the temperature at the interface x = s(t), Ts, an inequality for the coefficient q0 is obtained in order to have an exact solution. An equivalence between this problem and the analogous corresponding to a phase change problem with a temperature condition on the fixed face x = 0 is also obtained.
EEWWW!!: tangible interfaces for navigating into the human body
Authors: Edward De Guzman, F. Wai-ling Ho-Ching, Tara Matthews, Tye Rattenbury, Maribeth Back, Steve Harrison
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

Tangible interfaces have the potential to support learning for non-expert users, ease 3D navigation, and foster collaboration. We developed two physical devices aimed at school children for navigating a 3D virtual model of the human body. Results from a 40-subject user study suggest that these devices can encourage collaboration and improve the learnability of a navigational interface.
Assigning Season Tickets Fairly
Authors: Karl T. Ulrich, Scott Pearson, Thomas A. Grandine
Venue: Interfaces (1998)

After assigning Mariner season tickets in a rather unsatisfying way in 1996 to the individuals who had agreed to buy and divide them, we devised a more sophisticated approach in 1997 that poses and solves a mixed-integer-programming problem, and we obtained much more satisfactory results.
Internet-Type Queues with Power-Tailed Interarrival Times and Computational Methods for Their Analysis
Authors: Carl M. Harris, Percy H. Brill, Martin J. Fischer
Venue: INFORMS Journal on Computing (2000)

Internet traffic flows have often been characterized as having power-tailed (long-tailed, fat-tailed, heavy-tailed) packet interarrival times or service requirements. In this work, we focus on the development of complete and computationally efficient steady-state solutions of queues with power-tailed interarrival times when the service times are assumed exponential. The classical method for obtaining the steady-state probabilities and delay-time distributions for the G/M/1 (G/M/ c) queue requires solving a root-finding problem involving the Laplace-Stieltjes transform of the interarrival-time distribution function. Then the exponential service assumption is combined with the derived geometric arrival-point probabilities to get both the limiting general-time state and delay distributions. However, in situations where there is a power tail, the interarrival transform is typically quite complicated and never analytically tractable. In addition, it is possible that there is only a degenerate steady-state system-size probability distribution. Thus, an alternative approach to obtaining a steady-state solution is typically needed when power-tailed interarrivals are present. We exploit the exponentiality of the steady-state delay distributions for the G/M/1 and G/M/ c queues, using level-crossings and a transform approximation method, to develop an alternative root-finding problem when there are power-tailed interarrival times. Extensive computational results are given.
A Highly Regular and Scalable AES Hardware Architecture
Authors: Stefan Mangard, Manfred Aigner, Sandra Dominikus
Venue: IEEE Transactions on Computers (2003)

This article presents a highly regular and scalable AES hardware architecture, suited for full-custom as well as for semi-custom design flows. Contrary to other publications, a complete architecture (even including CBC mode) that is scalable in terms of throughput and in terms of the used key size is described. Similarities of encryption and decryption are utilized to provide a high level of performance using only a relatively small area (10,799 gate equivalents for the standard configuration). This performance is reached by balancing the combinational paths of the design. No other published AES hardware architecture provides similar balancing or a comparable regularity. Implementations of the fastest configuration of the architecture provide a throughput of 241 Mbits/sec on a 0.6 \mum CMOS process using standard cells.
A Dynamical Model of Visually-Guided Steering, Obstacle Avoidance, and Route Selection
Authors: Brett R. Fajen, William H. Warren, Selim Temizer, Leslie Pack Kaelbling
Venue: International Journal of Computer Vision (2003)

Using a biologically-inspired model, we show how successful route selection through a cluttered environment can emerge from on-line steering dynamics, without explicit path planning. The model is derived from experiments on human walking performed in the Virtual Environment Navigation Lab (VENLab) at Brown. We find that goals and obstacles behave as attractors and repellors of heading, the direction of locomotion, for an observer moving at a constant speed. The influence of a goal on turning rate increases with its angle from the heading and decreases exponentially with its distance; the influence of an obstacle decreases exponentially with angle and distance. Linearly combining goal and obstacle terms allows us to simulate paths through arbitrarily complex scenes, based on information about obstacles in view near the heading direction and a few meters ahead. We simulated the model on a variety of scene configurations and observed generally efficient routes, and verified this behavior on a mobile robot. Discussion focuses on comparisons between dynamical models and other approaches, including potential field models and explicit path planning. Effective route selection can thus be performed on-line, in simple environments as a consequence of elementary behaviors for steering and obstacle avoidance.
An investigation of the influence of indexing exhaustivity and term distributions on a document space
Authors: Dietmar Wolfram, Jin Zhang
Venue: Journal of the American Society for Information Science and Technology (2002)

The authors investigate the influence of index term distributions, and indexing exhaustivity levels on the document space within a visual information retrieval environment called DARE. Using combinations of three levels of term distributions (shallow, observed, steep) and indexing exhaustivity (low, observed, high), hypothetical document sets were generated and projected onto the DARE environment. The results from the simulated document sets demonstrate the importance of term distribution and exhaustivity characteristics on the density of document spaces and their implications for retrieval, particularly when different term weighting schemes are used. The results also demonstrate how different combinations of exhaustivity and term distributions may result in similar document space density characteristics.