ppxscal/embedding_network huggingface dataset:
Using terminological feedback for web search refinement: a log-based study
Authors: Peter Anick
Venue: Proceedings of the 26th annual international ACM SIGIR conference on Research and development in informaion retrieval (2003)

Although interactive query reformulation has been actively studied in the laboratory, little is known about the actual behavior of web searchers who are offered terminological feedback along with their search results. We analyze log sessions for two groups of users interacting with variants of the AltaVista search engine - a baseline group given no terminological feedback and a feedback group to whom twelve refinement terms are offered along with the search results. We examine uptake, refinement effectiveness, conditions of use, and refinement type preferences. Although our measure of overall session "success" shows no difference between outcomes for the two groups, we find evidence that a subset of those users presented with terminological feedback do make effective use of it on a continuing basis.
Termination Analysis in Active Databases
Authors: Danilo Montesi, Maria Bagnato, Cristina Dallera
Venue: Proceedings of the 1999 International Symposium on Database Engineering & Applications (1999)

We introduce a method for rule termination analysis within active databases which relies on evolution graphs simulating rule processing statically and considering both rule activation and deactivation. The evolution graph provides a more detailed analysis than traditional graph based approaches. We show that several termination analysis methods are captured by evolution graphs. The algorithm testing rules termination is presented and its correctness shown. The proposed approach turns out to be practical and general with respect to the various rule languages and thus it may be applied to several database systems.
Biometrics break-ins and band-aids
Authors: Nalini K. Ratha, Jonathan H. Connell, Ruud M. Bolle
Venue: Pattern Recognition Letters (2003)

Currently there is much interest in the use of biometrics for authentication and identification applications. This has been heightened most recently because of the threat of terrorism. Biometrics authentication and identification systems offer several advantages over systems based on knowledge or possession such as unsupervised (legacy) password/PIN-based systems and supervised (legacy) passport-based systems. To optimize security it is important that biometrics authentication systems are designed to withstand different sources of attack. We identify some such threats to biometrics systems and detail issues related to the tradeoff between security and convenience. We further show how to estimate a biometrics' intrinsic security, sometimes called a biometrics' individuality, with fingerprints as an example.
Toward a unification of text and link analysis
Authors: Brian D. Davison
Venue: Proceedings of the 26th annual international ACM SIGIR conference on Research and development in informaion retrieval (2003)

This paper presents a simple yet profound idea. By thinking about the relationships between and within terms and documents, we can generate a richer representation that encompasses aspects of Web link analysis as well as text analysis techniques from information retrieval. This paper shows one path to this unified representation, and demonstrates the use of eigenvector calculations from Web link analysis by stepping through a simple example.
A Hierarchical Combinatorial-Markov Method of Solving Complex Reliability Models
Authors: A R Sahner, S K Trivedi
Venue:  (1986)

The design process for complex, fault-tolerant systems needs to be supported by cost-effective and accurate techniques for design evaluation in order to facilitate trade-off analysis. Combinatorial models such as fault-trees and reliability block diagrams are efficient in both specification and evaluation of system models. But is is difficult if not impossible to allow for various types of dependency (such as repair dependency and near-coincident-fault type dependency), transient and intermittent faults, standby systems with warm spares, and so forth. Markov models can capture such interesting system behavior. However, the size of a Markov model for the evaluation of such a system may grow exponentially with the number of components in the system. One approach that has been successful in connection with ultra-high reliability modeling is called behavioral decomposition. This approach is based on the decomposition of the model along temporal lines, separately analyzing a fast submodel (corresponding to fault/error-handling behavior) and a slow submodel (corresponding to the fault-occurrence behavior). In practical problems, however, the fault-occurrence behavior itself gives rise to a large number of states in the underlying stochastic process. This paper presents an approach for avoiding the large state space problem in the fault-occurrence model while retaining the benefits of behavioral decomposition. The approach used is part of a general hierarchical modeling technique for solving complex reliability models that allows the flexibility of Markov models where necessary and retains the efficiency of combinatorial solution where possible. Examples are presented that show how combinations of models can be used to evaluate the reliability and availability of large systems.
The wide-diameter of the generalized de Bruijn graphs UG/sub B/(n,n(n+1))
Authors: J. D. L. Caro, F. P. Muga,  II
Venue: Proceedings of the 1996 International Symposium on Parallel Architectures, Algorithms and Networks (1996)

We shall show that for w=2(n-1), the w-diameter of the generalized de Bruijn graph UG/sub B/(n,n(n+1)) is 5 for n/spl ges/2.
Supplementary Symmetrical Logic Circuit Structure
Authors: Edgar "Dan" Olson
Venue: Proceedings of the Twenty Ninth IEEE International Symposium on Multiple-Valued Logic (1999)

The Supplementary Symmetrical Logic Circuit Structure (SUS-LOC) is a fully active, self sustaining architecture intended primarily for the design and fabrication of logic synthesizing circuits with a radix greater than two. Any r'-valued logic function of n'-places (where: r' is the radix and an integer greater than 1, and n' is an integer greater than 0) can be implemented with the SUS-LOC structure.
Product metrics for object-oriented systems
Authors: Sandeep Purao, Vijay Vaishnavi
Venue: ACM Computing Surveys (CSUR) (2003)

We survey metrics proposed for object-oriented systems, focusing on product metrics. The survey is intended for the purposes of understanding, classifying, and analyzing ongoing research in object-oriented metrics. The survey applies fundamental measurement theory to artifacts created by development activities. We develop a mathematical formalism that captures this perspective clearly, giving appropriate attention to the peculiarities of the object-oriented system developmenr process. Consistent representation of the available metrics, following this mathematical formalism, shows that current research in this area contains varying coverage of different products and their properties at different development stages. The consistent representation also facilitates several analyses including aggregation across metrics, usage across metrics, equivalent formulation of metrics by multiple researchers, and exploitation of traditional metrics for object-oriented metrics. We also trace the chronological development of research in this area, and uncover gaps that suggest opportunities for future research.
QR Factorization Algorithms for Coarse-Grained Distributed Systems
Authors: Christian H. Bischof
Venue:  (1988)

We present the techniques of adaptive blocking and incremental condition estimation which we believe to be useful for the computation of common matrix decompositions in high-performance environments. We apply these new techniques to algorithms for computing the Householder QR factorization with and without pivoting on a coarse-grained distributed system. For reasons of portability, we use a pipelined scheme on a ring of processors as the basis of our algorithms. To take advantage of possible floating point hardware on each node we develop a blocked version of the pipelined Householder QR algorithm that employs the compact WY representation for products of Householder matrices. While a strategy involving blocks of fixed width leads to increased floating point utilization per node, it also leads to increased load imbalance. To reconcile this tradeoff we introduce a variable width block strategy based on a model of the critical path of the algorithm. The resulting adaptive blocking strategy provides for good floating point performance per node while maintaining overall load balance. Experimental results on the Intel iPSC hypercube show that the adaptive blocking strategy performs indeed better than any fixed width blocking strategy. In the second part of our thesis we develop methods for introducing pivoting into the distributed QR factorization algorithm. Incorporating the traditional column pivoting strategy in a straightforward manner introduces a global synchronization constraint which results in increased communication overhead. A strictly local pivoting scheme avoids the resulting loss in efficiency, but has to be monitored for reliability. To this end, we introduce an incremental condition estimator which allows us to update the estimate of the smallest singular value of an upper triangular matrix $R$ as new columns are added to $R$. The update requires only $O(n)$ flops an the storage of $O(n)$ words between successive steps. Experiments indicate that the incremental condition estimator is reliable despite its small computational cost. Using the incremental condition estimator we are then able to guard against the selection of troublesome pivot columns in our local pivoting scheme at little extra cost. Simulation results show that the resulting algorithm is about as reliable as the traditional QR factorization algorithm with column pivoting.
Predicting Structure in Sparse Matrix Computations
Authors: John R. Gilbert
Venue:  (1986)

We describe the results of an experiment in which the Nuprl proof development system was used in conjunction with a collection of simple proof-assisting programs to constructively prove a substantial theorem of number theory. We believe that these results indicate the promise of an approach to reasoning about computationally meaningful mathematics by which proof construction and the results of formal reasoning are mathematically comprehensible.
Modal Matching for Correspondence and Recognition
Authors: S. Sclaroff, A. P. Pentland
Venue:  (1995)

Abstract Modal matching is a new method for establishing correspondences and computing canonical descriptions. The method is based on the idea of describing objects in terms of generalized symmetries, as defined by each object''s eigenmodes. The resulting modal description is used for object recognition and categorization, where shape similarities are expressed as the amounts of modal deformation energy needed to align the two objects. In general, modes provide a global-to-local ordering of shape deformation and thus allow for selecting which types of deformations are used in object alignment and comparison. In contrast to previous techniques, which required correspondence to be computed with an initial or prototype shape, modal matching utilizes a new type of finite element formulation that allows for an object''s eigenmodes to be computed directly from available image information. This improved formulation provides greater generality and accuracy, and is applicable to data of any dimensionality. Correspondence results with 2-D contour and point feature data are shown, and recognition experiments with 2-D images of hand tools and airplanes are described.
Color Optimal Self-Stabilizing Depth-First Token Circulation
Authors: Franck Petit, Vincent Villain
Venue: Proceedings of the 1997 International Symposium on Parallel Architectures, Algorithms and Networks (1997)

The notion of self-stabilization was first introduced by Dijkstra : it is the property for a system to eventually recover itself a legitimate state after any perturbation modifying the memory state. This paper proposes a self-stabilizing depth-first token circulation protocol for uniform rooted networks. Such an algorithm is very convenient to obtain the mutual exclusion or to construct a spanning tree. Our contribution consists of explaining how the basic depth-first token circulation protocol is nearly self-stabilizing and how to obtain a self-stabilizing protocol by just adding what is necessary to destroy cycles. We achieve an efficient algorithm working for any dynamic connected network in which the topology may change during the execution. Moreover, we shed a new light on proving self-stabilizing algorithms based on the locking property: a processor is locked if it eventually stops to modify its variables. We also improve the best known space complexity for this problem to the same as the basic algorithm, i.e. log2(D+1)+1 bits, D is the upper bound of node's degree.
Third generation and beyond wireless systems
Authors: P. Nicopolitidis, G. I. Papadimitriou, M. S. Obaidat, A. S. Pomportsis
Venue: Communications of the ACM (2003)

Exploring the capabilities of increased data transmission rates.
Estimates of variable stepsize Runge--Kutta methods for sectorial evolution equations with nonsmooth data
Authors: Wolf-Jürgen Beyn, Barnabas M. Garay
Venue: Applied Numerical Mathematics (2002)

We consider variable stepsize Runge-Kutta methods for semilinear evolution equations with a sectorial operator in the linear part. For nonsmooth initial data error estimates are derived that show the interplay of weak singularities and the classical order of convergence. There are no uniformity assumptions on the stepsizes, but we assume a Lipschitz condition for the nonlinearity and a stability function for the method that is less than 1 on the critical sector and vanishes at infinity. Using an extended operational calculus the proof combines a rearrangement trick with a discrete Gronwall estimate including weak singularities. Our main theorem complements respectively extends well-known results of Bakaev, Gonzalez, Lubich, Ostermann and Palencia.
Integrating metrics and models for software risk assessmen
Authors: J. P. Hudepohl, S. J. Aud, T. M. Khoshgoftaar, E. B. Allen, J. Mayrand
Venue: Proceedings of the The Seventh International Symposium on Software Reliability Engineering (1996)

Enhanced Measurement for Early Risk Assessment of Latent Defects (EMERALD) is a decision support system for assessing reliability risk. It is used by software developers and managers to improve telecommunications software service quality as perceived by the customer and the end user. Risk models are based on static characteristics of source code. This paper shows how a system such as EMERALD can enhance software development, testing, and maintenance by integration of: a software quality improvement strategy; measurements and models; and delivery of results to the desktop of developers in a timely manner. This paper also summarizes empirical experiments with EMERALD's models using data from large industrial telecommunications software systems. EMERALD has been applied to a very large system with over 12 million lines of source code within procedures. Experience and lessons learned are also discussed.
The New ATC System with an Autonomous Speed Control with On-Board Equipment
Authors: Masayuki Matsumoto, Akiyoshi Hosokawa, Satoru Kitamura, Dai Watanabe, Atsushi Kawabata
Venue: Proceedings of the Fifth International Symposium on Autonomous Decentralized Systems (2001)

This paper introduces a new digital ATC (Automatic Train Control device) system developed by East Japan Railway Company (JR East). In the current ATC, the central ATC logic device calculates permissive speed of each blocking section and controls speed of all trains. On the other hand, in the digital ATC, the central logic device calculates each position to which a train can move safely, and sends the information on positions to all trains. On each train, the on-board equipment calculates an appropriate braking pattern with the information, and controls velocity of the train. That is, in the new system, the device on each train autonomously calculates permissive speed of each train. These special features realize ideal speed control of each train making full use of its performance for acceleration and deceleration, which in turns allows high-density train operations.
Modeling the Landscape as a Dynamic Mosaic of Patches: Some Computatinal Aspects
Authors: Jianguo Wu
Venue:  (1993)

The only thing that is certain about Nature is its patchiness. Patchiness is ubiquitous, occurring across systems, organizational levels, and spatio-temporal scales. Traditional modeling approaches in ecology often fail to recognize spatial patchiness because they usually assume spatial homogeneity. A landscape may be viewed as a hierarchical mosaic system of patches that are different in their age, size, shape, content, and other aspects. The spatial change of the patch mosaic results in the landscape pattern, whereas the phase change of individual patches at the local scale and temporal change in patch mosaics at larger scales gives rise to the landscape dynamics. Following such a patch dynamics conceptualization, a spatially explicit patch dynamic modeling approach has been developed based on a serpentine annual grassland. The model has two basic submodels: a spatially-explicit, age/sizestructured patch demographic model and a multi-specific plant population dynamic model of a nonequilibrium island biogeographic type. In this paper, the basic structure and some computational aspects of the model are discussed. Keywords: Spatial modeling, patch dynamics, landscape modeling, patch maps, overlapping circles, dispersal, plant population dynamics The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Cross-Organizational Transaction Support for E-Services in Virtual Enterprises
Authors: Jochem Vonk, Paul Grefen
Venue: Distributed and Parallel Databases (2003)

In recent years, workflow management systems have become an accepted technology to support automation in process-centric environments. Lately, organizations concentrate more and more on their core business processes while outsourcing supporting processes to other organizations, thereby forming virtual enterprises. The organizations forming the virtual enterprise operate in a B2B e-commerce setting in which provider organizations perform e-services for consumer organizations. To apply workflow management technology in these virtual enterprises, current workflow management systems need to be extended to offer support for cross-organizational processes. Transaction support, already considered an important issue in intra-organizational workflow management systems, must be extended to deal with the cross-organizational aspects as well. This paper presents a high-level, compensation based transaction model and a flexible architecture to support this transaction model, as required by cross-organizational workflow processes. Characteristic of the model is the flexibility in rollback semantics by combining rollback modes and rollback scopes. This is supported by a dynamically composed architecture that is configured using the agreements that are specified in an electronic contract that has been established between the participating organizations. The transaction model supported by the dynamically composed architecture is implemented in a prototype system, based on commercial workflow management technology.
A wireless link protocol: design by refinement
Authors: M. G. Gouda, S. Paul
Venue: Proceedings of the 1995 International Conference on Network Protocols (1995)

We develop an asymmetric protocol for wireless communication in a step-by-step manner. We start with a very simple protocol and prove its correctness. Then we relax the assumptions of the simple protocol one by one, verifying the correctness of the protocol at each step as we relax the assumptions. This process is continued in a systematic manner until no assumptions are left. The novelty of the paper lies in the way the assumptions are relaxed without violating the correctness properties of the protocol while at the same time making the protocol efficient. The final result is a provably correct protocol which is also efficient for wireless channels
Queueing Dynamics and Maximal Throughput Scheduling in Switched Processing Systems
Authors: Mor Armony, Nicholas Bambos
Venue: Queueing Systems: Theory and Applications (2003)

We study a processing system comprised of parallel queues, whose individual service rates are specified by a global service mode (configuration). The issue is how to switch the system between various possible service modes, so as to maximize its throughput and maintain stability under the most workload-intensive input traffic traces (arrival processes). Stability preserves the job inflow&ndash;outflow balance at each queue on the traffic traces. Two key families of service policies are shown to maximize throughput, under the mild condition that traffic traces have long-term average workload rates. In the first family of cone policies, the service mode is chosen based on the system backlog state belonging to a corresponding cone. Two distinct policy classes of that nature are investigated, MaxProduct and FastEmpty. In the second family of batch policies (BatchAdapt), jobs are collectively scheduled over adaptively chosen horizons, according to an asymptotically optimal, robust schedule. The issues of nonpreemptive job processing and non-negligible switching times between service modes are addressed. The analysis is extended to cover feed-forward networks of such processing systems/nodes. The approach taken unifies and generalizes prior studies, by developing a general trace-based modeling framework (sample-path approach) for addressing the queueing stability problem. It treats the queueing structure as a deterministic dynamical system and analyzes directly its evolution trajectories. It does not require any probabilistic superstructure, which is typically used in previous approaches. Probability can be superposed later to address finer performance questions (e.g., delay). The throughput maximization problem is seen to be primarily of structural nature. The developed methodology appears to have broader applicability to other queueing systems.
Processor-Time Tradeoffs under Bounded-Speed Message Propagation: Part I, Upper Boundes
Authors: Gianfranco Bilardi, Franco Preparata
Venue:  (1995)

Upper bounds are derived for the processor-time tradeoffs of machines such as linear arrays and two-dimensional meshes, which are compatible with the physical limitation expressed by bounded-speed propagation of messages (due to the finiteness of the speed of light). It is shown that parallelism and locality combined may yield speedups superlinear in the number of processors. The speedups are inherent, due to the optimality of the obtained tradeoffs as established in a companion paper. Simulations are developed of multiprocessor machines by analogous machines with fewer processors. A crucial role is played by the hierarchical nature of the memory system. A divide-and-conquer technique for hierarchical memories is developed, based on the graph-theoretic notion of topological separator. For multiprocessors, this technique also requires a careful balance of memory access and interprocessor communication costs, which leads to non-intuitive orchestrations of the simulation process.