ppxscal/embedding_network huggingface dataset:
Current Practice and a Direction Forward in Checkpoint/Restart Implementations for Fault Tolerance
Authors: Jose Carlos Sancho, Fabrizio Petrini, Kei Davis, Roberto Gioiosa, Song Jiang
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 18 - Volume 19 (2005)

Checkpoint/restart is a general idea for which particular implementations enable various functionalities in computer systems, including process migration, gang scheduling, hibernation, and fault tolerance. For fault tolerance, in current practice, implementations can be at user-level or system-level. User-level implementations are relatively easy to implement and portable, but suffer from a lack of transparency, flexibility, and efficiency, and in particular are unsuitable for the autonomic (self-managing) computing systems envisioned as the next revolutionary development in system management. In contrast, a system-level implementation can exhibit all of these desirable features, at the cost of a more sophisticated implementation, and is seen as an essential mechanism for the next generation of fault tolerant-and ultimately autonomic-large-scale computing systems. Linux is becoming the operating system of choice for the largest-scale machines, but development of system-level checkpoint/restart mechanisms for Linux is still in its infancy, with all extant implementations exhibiting serious deficiencies for achieving transparent fault tolerance. This paper provides a survey of extant implementations in a natural taxonomy, highlighting their strengths and inherent weaknesses.
A Logger system based on web services
Authors: B. Horn, H. Balakrishnan, B. T. Maniampadavathu, J. Warnes, D. A. Elko
Venue: IBM Systems Journal (2004)

The Logger System described in this article is a general purpose set of component interfaces for logging data in a distributed, heterogeneous computing environment. Fundamentally, it serves as an intermediary between log artifact producers and log artifact consumers. It is designed to virtualize existing logging systems including the z/OS® System Logger, Microsoft Windows® event logging, and the UNIX® syslog facility. The Logger System is outlined using the conventions defined in the recently released Web Services Resource Framework (WSRF) and provides an example of how this framework might be used to define a meta-OS (operating system) for grid computing.
An Empirical User Rating of Popular Search Engines Using RankPower
Authors: Xiannong Meng, Ty Clark
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume II - Volume 02 (2005)

We present in this paper the effectiveness and the feasibility of measuring search engine efficiency using RankPower, a single value measurement. RankPower rates the search engines by computing the number and the rank of relevant URLs among the returned results. This is different from traditional performance measures of information retrieval systems using the precision and recall rates. The RankPower is much more easier to compute and much more intuitive for ordinary web search users. The conclusions are supported by a set of empirical results collected from the experiments that the authors designed and carried out.
Learning user interest for image browsing on small-form-factor devices
Authors: Xing Xie, Hao Liu, Simon Goumaz, Wei-Ying Ma
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2005)

Mobile devices which can capture and view pictures are becoming increasingly common in our life. The limitation of these small-form-factor devices makes the user experience of image browsing quite different from that on desktop PCs. In this paper, we first present a user study on how users interact with a mobile image browser with basic functions. We found that on small displays, users tend to use more zooming and scrolling actions in order to view interesting regions in detail. From this fact, we designed a new method to detect user interest maps and extract user attention objects from the image browsing log. This approach is more efficient than image-analysis based methods and can better represent users' actual interest. A smart image viewer was then developed based on user interest analysis. A second experiment was carried out to study how users behave with such a viewer. Experimental results demonstrate that the new smart features can improve the browsing efficiency and are a good compliment to traditional image browsers.
Generalized integrating factor methods for stiff PDEs
Authors: S. Krogstad
Venue: Journal of Computational Physics (2005)

The integrating factor (IF) method for numerical integration of stiff nonlinear PDEs has the disadvantage of producing large error coefficients when the linear term has large norm. We propose a generalization of the IF method, and in particular construct multistep-type methods with several orders of magnitude improved accuracy. We also consider exponential time differencing (ETD) methods, and point out connections with a particular application of the commutator-free Lie group methods. We present a new fourth order ETDRK method with improved accuracy. The methods considered are compared in several numerical examples.
Privacy gradients: exploring ways to manage incidental information during co-located collaboration
Authors: Kirstie Hawkey, Kori M. Inkpen
Venue: CHI '05 extended abstracts on Human factors in computing systems (2005)

This research introduces privacy issues related to the viewing of incidental information during co-located collaboration. Web browsers were the representative application used in this research as they have several convenience features that record and display traces of previous web page visits. A one-week field study examined how individuals perceive privacy needs relating to the later incidental viewing of traces of their browsing activity. Participants used a 4-tier privacy gradient to classify the privacy of their actual web browsing. The results revealed per window patterns of privacy during browsing with streaks at given privacy levels and relatively few transitions between levels. Management of incidental information is a complex problem due to multiple viewing contexts, individual differences, and the large volume of information. These privacy patterns suggest that a semi-automated approach to privacy management may be feasible.
Book review: Blackboard Architectures and Applications Edited by V. Jagannathan, Rajendra Dodhiawala, and Lawrence S. Baum (Academic Press)
Venue: ACM SIGART Bulletin (1990)

The recent publication of two books on blackboard architectures, Blackboard Architectures and Applications (eds. V. Jagannathan, R. Dodhiawala, and L.S. Baum, Academic Press, Inc., 1989) and Blackboard Systems (eds. R. Engelmore and T. Morgan, Addison Wesley, 1988) is an indication of the maturity and current popularity of this particular area of AI research. Blackboard Architectures and Applications, the book under review here, is the most current of these two works.
Reverse engineering of object oriented code
Authors: Paolo Tonella
Venue: Proceedings of the 27th international conference on Software engineering (2005)

During software evolution, programmers devote most of their effort to the understanding of the structure and behavior of the system. For Object-Oriented code, this might be particularly hard, when multiple, scattered objects contribute to the same function. Design views offer an invaluable help, but they are often not aligned with the code, when they are not missing at all.This tutorial describes some of the most advanced techniques that can be employed to reverse engineer several design views from the source code. The recovered diagrams, represented in UML (Unified Modeling Language), include class, object, interaction (collaboration and sequence), state and package diagrams. A unifying static code analysis framework used by most of the involved algorithms is presented at the beginning of the tutorial. A single running example is referred all over the presentation. Trade-offs (e.g., static vs. dynamic analysis), limitations and expected benefits are also discussed.
McDonnell Douglas Electronic Systems Company: description of the INLET system used for MUC-3
Authors: David de Hilster, Amnon Meyers
Venue: Proceedings of the 3rd conference on Message understanding (1991)

During the past nine months, our language processing effort has focused on implementing a new NLP system called INLET. INLET relies heavily on the methodology developed for the preceding VOX system. The goal of this work is to produce an NLP shell that can be customized to a variety of tasks and domains.
US Supercomputing Receives Multifaceted Boost
Authors: Greg Goth
Venue: IEEE Distributed Systems Online (2005)

For years, the US-based high-performance computing community has warned that the federal government's lagging interest and investment could cause serious long-term consequences for the US. Recent events signal the warnings haven't gone unheeded.
Integrated Learning of Saliency, Complex Features, and Object Detectors from Cluttered Scenes
Authors: Dashan Gao, Nuno Vasconcelos
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 2 - Volume 02 (2005)

A novel procedure for object detection from cluttered scenes is proposed. It consists of an integrated solution to the problems of learning 1) a saliency detection module tuned to a class of objects of interest, 2) a set of complex features that achieves the optimal trade-off, in a minimum probability of error sense, between discrimination and generalization ability, and 3) a large-margin object detector. All stages of the new procedure have some degree of biological motivation and this is shown to enable a computationally efficient solution that is scalable to problems containing large numbers of object classes. Experimental evidence is given in support of the arguments that different levels of feature complexity are optimal for different object classes, and that optimal features range from parts to templates, depending on the variability of the object class.
Positivity and monotony properties of the de Branges functions
Authors: Wolfram Koepf, Dieter Schmersau
Venue: Journal of Computational and Applied Mathematics (2005)

In his 1984 proof of the Bieberbach and Milin conjectures de Branges used a positivity result of special functions τkn(t) which follows from an identity about Jacobi polynomial sums that was published by Askey and Gasper in 1976.In 1991 Weinstein presented another proof of the Bieberbach and Milin conjectures, also using a special function system Λkn(t) which (by Todorov and Wilf) was realized to be directly connected with de Branges', τ˙kn(t) = -kΛkn(t), and the positivity results in both proofs τ˙kn ≤ 0 are essentially the same.By the relation τkn(t) ≤ 0, the de Branges functions τkn(t) are monotonic, and τkn(t) ≥ 0 follows. In this article, we reconsider the de Branges and Weinstein functions, find more relations connecting them with each other, and make the above positivity and monotony result more precise, e.g., by showing τkn(t) ≥ (n-k+1)e-kt.
Performance Preserving Network Downscaling
Authors: Fragkiskos Papadopoulos, Konstantinos Psounis, Ramesh Govindan
Venue: Proceedings of the 38th annual Symposium on Simulation (2005)

The Internet is a large, complex, heterogeneous system operating at very high speeds and consisting of a large number of users. Researchers use a suite of tools and techniques in order to understand the performance of networks: measurements, simulations, and deployments on small to medium-scale testbeds. This work considers a novel addition to this suite: a class of methods to scale down the topology of the Internet that enables researchers to create and observe a smaller replica, and extrapolate its performance to the expected performance of the larger Internet. The key insight that we leverage in this work is that only the congested links along the path of each flow introduce sizable queueing delays and dependencies among flows. Hence, one might hope that the network properties can be captured by a topology that consists of the congested links only. We show that for a network that is shared by TCP flows it is possible to achieve this kind of performance scaling. We also show that simulating a scaled topology can be up to two orders of magnitude faster than simulating the original topology.
An Adapter to Promote Reusability of CORBA Components in COBOL
Authors: Chia-Chu Chiang
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume II - Volume 02 (2005)

Common Object Request Broker Architecture (CORBA) is an enabling technology that supports heterogeneous applications to work together over networks. However, the implementation of CORBA components suffers from high interaction complexities in the component that seriously degrades the component independence for reuse. In this paper, we are presenting an adapter for implementing CORBA components in COBOL for reuse. The adapter is used to isolate, encapsulate, and manage a component's interactions outside the component. The use of adapters increases the reusability of components and also simplifies the integration of the components to an application. In addition, for organizations using an open-source implementation of CORBA, the work discussed in this paper helps them improve their CORBA middleware implementations to support COBOL interoperability and reuse.
Numerical simulation of stochastic PDEs for excitable media
Authors: Tony Shardlow
Venue: Journal of Computational and Applied Mathematics (2005)

We discuss the numerical solution of a number of stochastic perturbations of the Barkley model of excitable media, widely used in the study of spiral waves. Two numerical methods are considered for solving this equation. one based on Barkley's original formulation and one based oil spectral methods. It is found to be beneficial to modify the nonlinearity describing the reaction kinetics. An efficient method of approximating the Wiener process is presented. The effectiveness of the methods depends on the stochastic PDE under consideration.
COMMIT: A Sender-Centric Truthful and Energy-Efficient Routing Protocol for Ad Hoc Networks with Selfish Nodes
Authors: Stephan Eidenbenz, Giovanni Resta, Paolo Santi
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 12 - Volume 13 (2005)

We consider the problem of establishing a route and sending packets between a source/destination pair in ad hoc networks composed of rational selfish nodes, whose purpose is to maximize their own utility. In order to motivate nodes to follow the protocol specification, we use side payments that are made to the forwarding nodes. Our goal is to design a fully distributed algorithm such that: (i) a node is always better off participating in the protocol execution (individual rationality), (ii) a node is always better off behaving according to the protocol specification (truthfulness), (iii) messages are routed along the most energy-efficient path, and (iv) the message complexity is reasonably low.We introduce the COMMIT protocol for individually rational, truthful, and energy-efficient routing in ad hoc networks.To the best of our knowledge, this is the first ad hoc routing protocol with these features. COMMIT is based on the VCG payment scheme, in conjunction with a novel game-theoretic technique to achieve truthfulness for the sender node.By means of simulation, we show that the inevitable economic inefficiency is small.As an aside, our work demonstrates the advantage of using a cross-layer approach to solving problems: leveraging the existence of an underlying topology control protocol, we are able to simplify the design and analysis of our routing protocol, and to reduce its message complexity.On the other hand, our investigation of the routing problem in presence of selfish nodes disclosed a new metric under which topology control protocols can be evaluated: the cost of cooperation.
Skin color segmentation method based on mixture of gaussians and its application in learning system for finger alphabet
Authors: Peter Gejgus, Jaroslav Placek, Martin Sperka
Venue: Proceedings of the 5th international conference on Computer systems and technologies (2004)

The paper deals with method used for segmentation of human skin from the image. Applications of the method are in the fields of gesture recognition, face detection or motion capture. After the detailed method description, the experimental interactive program designed for helping deaf students learn finger alphabet is presented. This program is part of the sign language system, which uses CCD camera, directed to the user hands with goal to capture the image and compute the matching of the posture with a desired shape.
An Optically Differential Reconfigurable Gate Array VLSI Chip with a Dynamic Reconfiguration Circuit
Authors: Minoru Watanabe, Fuminori Kobayashi
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Workshop 3 - Volume 04 (2005)

An Optically Differential Reconfigurable Gate Array (ODRGA) is a type of Field Programmable Gate Array (FPGA), but its gate array can be reconfigured optically in less than 6 ns. We have fabricated a 68 gate-count ODRGA. However, optical differential reconfiguration circuits, which are capable of optical detection of configuration contexts and which can support reconfiguration of an arbitrary part of its gate array bit-by-bit, occupy up to 47% of the implementation area of ODRGA-VLSI chip and prevent realization of a high gate-count ODRGA. Therefore, a dynamic optical differential reconfiguration circuit was developed to reduce the implementation area of optical reconfiguration circuits. It has been evaluated separately. This paper presents the first 476 gate count ODRGA-VLSI chip with a standard 0.35 µm 3-metal CMOS process technology using an improved dynamic optical differential reconfiguration circuit. In addition, the dynamic reconfiguration frequency and performance of logic blocks are shown using HSPICE simulation results. Finally, this paper presents an estimation of the use of a standard 0.35 µm 3-metal 14.2 x 14.2 mm chip.
Optimal Two-Stage Algorithms for Group Testing Problems
Authors: Annalisa De Bonis, Leszek Gasieniec, Ugo Vaccaro
Venue: SIAM Journal on Computing (2005)

Group testing refers to the situation in which one is given a set of objects ${\cal O}$, an unknown subset ${\cal P}\subseteq {\cal O}$, and the task of determining ${\cal P}$ by asking queries of the type "does ${\cal P}$ intersect $\cal Q$?," where $\cal Q$ is a subset of ${\cal O}$. Group testing is a basic search paradigm that occurs in a variety of situations such as quality control testing, searching in storage systems, multiple access communications, and data compression, among others. Group testing procedures have been recently applied in computational molecular biology, where they are used for screening libraries of clones with hybridization probes and sequencing by hybridization.Motivated by particular features of group testing algorithms used in biological screening, we study the efficiency of two-stage group testing procedures. Our main result is the first optimal two-stage algorithm that uses a number of tests of the same order as the information-theoretic lower bound on the problem. We also provide efficient algorithms for the case in which there is a Bernoulli probability distribution on the possible sets ${\cal P}$, and an optimal algorithm for the case in which the outcome of tests may be unreliable because of the presence of "inhibitory" items in ${\cal O}$. Our results depend on a combinatorial structure introduced in this paper. We believe that it will prove useful in other contexts, too.
Using AD to solve BVPs in MATLAB
Authors: L. F. Shampine, Robert Ketzscher, Shaun A. Forth
Venue: ACM Transactions on Mathematical Software (TOMS) (2005)

The MATLAB program bvp4c solves two--point boundary value problems (BVPs) of considerable generality. The numerical method requires partial derivatives of several kinds. To make solving BVPs as easy as possible, the default in bvp4c is to approximate these derivatives with finite differences. The solver is more robust and efficient if analytical derivatives are supplied. In this article we investigate how to use automatic differentiation (AD) to obtain the advantages of analytical derivatives without giving up the convenience of finite differences. In bvp4cAD we have approached this ideal by a careful use of the MAD AD tool and some modification of bvp4c.
Multiple Wilson and Jacobi-Piñeiro polynomials
Authors: B. Beckermann, J. Coussement, W. Van Assche
Venue: Journal of Approximation Theory (2005)

We introduce multiple Wilson polynomials, which give a new example of multiple orthogonal polynomials (Hermite-Padé polynomials) of type II. These polynomials can be written as a Jacobi-Piñeiro transform, which is a generalization of the Jacobi transform for Wilson polynomials, found by Koornwinder. Here we need to introduce Jacobi and Jacobi-Piñeiro polynomials with complex parameters. Some explicit formulas are provided for both Jacobi-Piñeiro and multiple Wilson polynomials, one of them in terms of Kampé de Fériet series. Finally, we look at some limiting relations and construct a part of a multiple AT-Askey table.
A Theoretical Study of a Generalized Version of Kleinberg's HITS Algorithm
Authors: Maristella Agosti, Luca Pretto
Venue: Information Retrieval (2005)

Kleinberg's HITS algorithm (Kleinberg 1999), which was originally developed in a Web context, tries to infer the authoritativeness of a Web page in relation to a specific query using the structure of a subgraph of the Web graph, which is obtained considering this specific query. Recent applications of this algorithm in contexts far removed from that of Web searching (Bacchin, Ferro and Melucci 2002, Ng et al. 2001) inspired us to study the algorithm in the abstract, independently of its particular applications, trying to mathematically illuminate its behaviour. In the present paper we detail this theoretical analysis. The original work starts from the definition of a revised and more general version of the algorithm, which includes the classic one as a particular case. We perform an analysis of the structure of two particular matrices, essential to studying the behaviour of the algorithm, and we prove the convergence of the algorithm in the most general case, finding the analytic expression of the vectors to which it converges. Then we study the symmetry of the algorithm and prove the equivalence between the existence of symmetry and the independence from the order of execution of some basic operations on initial vectors. Finally, we expound some interesting consequences of our theoretical results.
Improving and Stabilizing Parallel Computer Performance Using Adaptive Backfilling
Authors: David Talby, Dror G. Feitelson
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Papers - Volume 01 (2005)

The scheduler is a key component in determining the overall performance of a parallel computer, and as we show here, the schedulers in wide use today exhibit large unexplained gaps in performance during their operation. Also, different scheduling algorithms often vary in the gaps they show, suggesting that choosing the correct scheduler for each time frame can improve overall performance. We present two adaptive algorithms that achieve this: One chooses by recent past performance, and the other by the recent average degree of parallelism, which is shown to be correlated to algorithmic superiority. Simulation results for the algorithms on production workloads are analyzed, and illustrate unique features of the chaotic temporal structure of parallel workloads. We provide best parameter configurations for each algorithm, which both achieve average improvements of 10% in performance and 35% in stability for the tested workloads.