ppxscal/embedding_network huggingface dataset:
Tuning System-Dependent Applications with Alternative MPI Calls A Case Study
Authors: Thuy T. Le
Venue: Proceedings of the Third ACIS Int'l Conference on Software Engineering Research, Management and Applications (2005)

This paper shows the effectiveness of using optimized MPI calls for MPI based applications on different architectures. Using optimized MPI calls can result in reasonable performance gain for most of MPI based applications running on most of high-performance distributed systems. Since relative performance of different MPI function calls and system architectures can be uncorrelated, tuning system-dependent MPI applications by exploring the alternatives of using different MPI calls is the simplest but most effective optimization method. The paper first shows that for a particular system, there are noticeable performance differences between using various MPI calls that result in the same communication pattern. These performance differences are in fact not similar across different systems. The paper then shows that good performance optimization for an MPI application on different systems can be obtained by using different MPI calls for different systems. The communication patterns that were experimented in this paper include the point-to-point and collective communications. The MPI based application used for this study is the general-purpose transient dynamic finite element application and the benchmark problems are the public domain 3-D car crash problems. The experiment results show that for the same communication purpose, using alternative MPI calls can result in quite different communication performance on the Fujitsu HPC2500 system and the 8-node AMD Athlon cluster, but very much the same performance on the other systems such as the Intel Itanium2 and the AMD Opteron clusters.
A Dependable Online Testing and Upgrade Architecture for Real-Time Embedded Systems
Authors: Kihwal Lee, Lui Sha
Venue: Proceedings of the 11th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (2005)

When real-time embedded system software needs to be upgraded, it will be more dependable if the new software is sufficiently tested on the actual deployment platform. The challenge is to provide a safeguard for protecting the normal operations from faulty upgrades. However, the safeguard must be not only efficient but also able to be added and taken away as needed without shutting down the normal operations. We have developed an architecture based on Simplex Architecture and Process Resurrection and have applied it to the inverted pendulum control system. The measurements show that the overhead is small and justifiable.
News Item Extraction for Text Mining inWeb Newspapers
Authors: kjetil Norvag, Randi Oyri
Venue: Proceedings of the International Workshop on Challenges in Web Information Retrieval and Integration (2005)

Web newspapers provide a valuable resource for information. In order to benefit more from the available information, text mining techniques can be applied. However, because each newspaper page often covers a lot of unrelated topics, page-based data mining will not always give useful results. In order to improve on complete-page mining, we present an approach based on extracting the individual news items from the web pages and mining these separately. Automatic news item extraction is a difficult problem, and in this paper we also provide strategies solving that task. We study the quality of the news item extraction, and also provide results from clustering the extracted news items.
The Astro Spiral Jump: an auto thrill show stunt designed via simulation
Authors: Raymond R. McHenry
Venue: ACM SIGSIM Simulation Digest (1978)

An unusual application of a digital simulation of automobile dynamics to the design of a thrill show stunt is described. The rationale for development of the simulation, which is intended primarily for highway safety applications, is discussed and the general analytical approach is described. Computer graphics displays of simulation outputs, consisting of detailed perspective drawings of the vehicle and terrain features or obstacles at selected intervals of time during a simulated maneuver, are presented as figures in the text. For the presentation of the paper, computer graphics displays of simulation outputs will be animated through the use of motion picture film. Also, motion picture coverage of both developmental tests and public performances of the Astro Spiral Jump will be shown.
Enhancing Scientific Workflows with Secure Shell Functionality in UNICORE Grids
Authors: Morris Riedel, Daniel Mallmann, Achim Streit
Venue: Proceedings of the First International Conference on e-Science and Grid Computing (2005)

The UNICORE Grid technology provides a seamless, secure and intuitive access to distributed Grid resources such as computational or storage related resources. In addition, its extensible character through application-specific plugins and its enhancements developed in various European-funded projects leads to the UNICORE technology that is used in daily production at many supercomputer centers and research facilities world-wide today. In this paper we present an enhancement that provides the dynamic capabilities of a Secure Shell terminal within the UNICORE Grid technology while single sign-on remains. This enhancement allows the integration of the dynamic work-behavior of scientists, or existing scientific applications, to be more integrated into the usual workflow with UNICORE and therefore in collaborative Grid environments. As a well-known tool in the scientific community, a Secure Shell terminal provides the most flexible way of working on remote systems that no Graphical User Interface or advanced tooling in Grid computing can ever provide.
Flexible pseudo-relevance feedback via selective sampling
Authors: Tetsuya Sakai, Toshihiko Manabe, Makoto Koyama
Venue: ACM Transactions on Asian Language Information Processing (TALIP) (2005)

Although Pseudo-Relevance Feedback (PRF) is a widely used technique for enhancing average retrieval performance, it may actually hurt performance for around one-third of a given set of topics. To enhance the reliability of PRF, Flexible PRF has been proposed, which adjusts the number of pseudo-relevant documents and/or the number of expansion terms for each topic. This paper explores a new, inexpensive Flexible PRF method, called Selective Sampling, which is unique in that it can skip documents in the initial ranked output to look for more &ldquo;novel&rdquo; pseudo-relevant documents. While Selective Sampling is only comparable to Traditional PRF in terms of average performance and reliability, per-topic analyses show that Selective Sampling outperforms Traditional PRF almost as often as Traditional PRF outperforms Selective Sampling. Thus, treating the top P documents as relevant is often not the best strategy. However, predicting when Selective Sampling outperforms Traditional PRF appears to be as difficult as predicting when a PRF method fails. For example, our per-topic analyses show that even the proportion of truly relevant documents in the pseudo-relevant set is not necessarily a good performance predictor.
Beyond Robotics: A New Proactive Research Initiative from the EU IST Program
Authors: Pekka Karp
Venue: Artificial Life (2005)

A research initiative on embodied artificial intelligence has been launched in 2004 by the Future and Emerging Technologies (FET) arm of the Information Society Technologies (IST) programme of the European Union. The initiative is called "Beyond Robotics" to emphasize that the research projects funded are required to set ambitious objectives and to aim at breakthroughs going well beyond the state of the art. Four projects worth 20 M E of EC funding were selected for 2004 &ndash; 2008 to address the objectives of the initiative. 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
Improving the quality of information technology (it) security audits for federal agencies
Authors: Ellen Pieklo
Venue:  (2005)

The study examines Government Accountability Office (GAO) IT security audit reports for a two-year period to assess the quality of these reports, addressing three questions. The first question is: do GAO reports provide a high-quality, independent assessment of IT security programs? The second question is: do GAO reports provide federal agencies with sufficient information to correct IT security problems? The third question is: Do GAO reports provide a feedback mechanism to allow another agency to learn from the mistakes of another agency? Federal agencies are spending over $50 billion per year on information technology and are encouraged to be results driven yet these same agencies are unable to manage and protect the information. In a recent assessment, over half of federal agencies received a score of &ldquo;C&rdquo; or &ldquo;D&rdquo;. In 2004, the average score is still D+. Other reports showed that sensitive data is available on public web sites, fraud has been committed against the government, and federal computer systems are exposed to computer attacks and reached over 1.4 million attacks in a 2003. This study looked at the GAO reports to determine if the current audit reports provide an effective approach to evaluating IT security environments, using the concepts of validity, reliability, and practicality. Two hundred and six findings were evaluated from these reports. The study concludes that IT security audits do not effectively assess IT security environments. Relative to the three questions, the study found: (1) GAO reports do not provide a high-quality, independent assessment of IT security programs (2) reports do not provide federal agencies with sufficient information to correct IT security problems and (3) GAO reports do not provide a feedback mechanism to allow another agency to learn from the mistakes of another agency. In addition, the study recommends: (1) federal agencies conduct IT security audits enabling statistical sampling; (2) federal agencies use better research methods; and (3) federal agencies improve the feedback processes. In addition, the study introduces the Ten Step Security Delphi Model, which can be used as a technique to prioritize security weaknesses.
Research note: Dependable user-level socket over dual networks
Authors: Nader Mohamed, Jameela Al-Jaroodi, Hong Jiang
Venue: Journal of Parallel and Distributed Computing (2005)

Message duplication over multiple links can enhance the communication reliability and availability among distributed processes running on clusters or networked workstations. In addition, message striping over multiple links can enhance communication throughput and transfer times. This paper introduces optimized techniques to provide a dependable user-level socket that enhances the reliability and performance of message deliveries over dual network interfaces. The proposed techniques are designed to work on top of reliable transport protocols. In addition, a technique for efficient duplication of messages on dual networks to enhance both communication reliability and performance on top of reliable transport protocol is proposed. A prototype socket based on this model is developed and evaluated. The experimental evaluations of the proposed model indicate good communication reliability and performance gains over conventional methods.
Achieving Scalable Capacity in Wireless Networks with Adaptive Power Control
Authors: Wang Hei Ho, Soung Chang Liew
Venue: Proceedings of the The IEEE Conference on Local Computer Networks 30th Anniversary (2005)

The seminar work of Gupta and Kumar [1] showed that multi-hop wireless networks with capacity scalable with the number of nodes, n, are achievable in theory. The transport capacity scales as \Theta \sqrt n, while the capacity scales as \Theta (n) . A subsequent study [2], on the other hand, showed that the capacity of IEEE 802.11 networks does not scale with n due to its carrier-sensing mechanism. This prior work, however, has not considered the use of power control. The main contributions of this paper are three-folds: 1) we provide an analytical framework for deriving the design requirements of adaptive power control strategies; 2) we demonstrate that 802.11 networks are scalable with power control; 3) however, an enhanced MAC protocol called Selective Disregard of NAVs (SDN) can achieve substantially higher capacity with an adaptive power control scheme; in particular, adaptive power control allows SDN to achieve capacity within 75% of the theoretical optimal capacity of infrastructure-mode wireless networks. A reason why adaptive power control works well is that it takes into consideration the fundamental mutual-interference relationships between links in the vicinity of each other, and adjust their relative transmit powers to reduce these interferences to a large extent that is possible theoretically.
P2P Architecture for Self-Atomic Memory
Authors: Emmanuelle Anceaume, Maria Gradinariu, Vincent Gramoli, Antonino Virgillito
Venue: Proceedings of the 8th International Symposium on Parallel Architectures,Algorithms and Networks (2005)

We propose an architecture for self-adjusting and self-healing atomic memory in highly dynamic systems exploiting peer-to-peer (p2p) techniques. Our approach, named SAM, brings together new and old research areas such as p2p overlays, dynamic quorums and replica control. In SAM, nodes form a connected overlay. To emulate the behavior of an atomic memory we use intersected sets of nodes, namely quorums, where each node hosts a replica of an object. In our approach, a quorum set is obtained by performing a deterministic traversal of the overlay. The SAM overlay features self-! capabilities: that is, the overlay self-heals on the fly when nodes hosting replicas leave the system and the number of active replicas in the overlay dynamically self-adjusts with respect to the object load. In particular, SAM pushes requests from loaded replicas to less solicited replicas. If such replicas do not exist, the replicas overlay selfadjusts to absorb the extra load without breaking the atomicity. We propose a distributed implementation of SAM where nodes exploit only a restricted local view of the system, for the sake of scalability.
Locally Linear Embedding for Markerless Human Motion Capture Using Multiple Cameras
Authors: Therdsak Tangkuampien, Tat-Jun Chin
Venue: Proceedings of the Digital Image Computing on Techniques and Applications (2005)

We investigate the possibility of applying non-linear manifold learning techniques to aid in markerless human motion capturing. We hypothesize that the set of segmented binary images (in a constrained environment) of a person in all possible poses lie on a low dimensional manifold in the image space. Since it is not feasible to densely sample the manifold by capturing real life images, we propose to learn the manifold by using synthetic images. An accurate 3D mesh of the actor can be used to generate the synthetic 3 dimensional virtual data. A set of poses (a collection of hierarchical joint angles defining the stance of a person at a point in time) ranging the space of possible human motion is used to animate the mesh and the synthetic images are then captured by virtual cameras. We hypothesize that these vectorized synthetic images lie on a low dimensional manifold shared by the pose vectors. We then align the synthetic image and pose pairs to form a common manifold by constraining them to be equivalent. Given a new set of real images of the actor, the system can then project the captured image onto the aligned common manifold and determine the closest synthetic poses to use to linearly generate the output pose. Our experiments exhibit promising results for our method.
Process-Based Experiment for Design Tool Assessment in Real-Time Safety-Critical Software Development
Authors: Andrew J. Kornecki, Janusz Zalewski
Venue: Proceedings of the 29th Annual IEEE/NASA on Software Engineering Workshop (2005)

The paper presents selected experimental results of evaluating six real-time software development tools for use in safety-critical systems. The experiments were designed to collect data, such as project effort, code size, functionality, traceability, etc., in four stages: preparation, model/code development, measurements, and postmortem. Preliminary experiments were conducted to enable fully controlled experiments for the development of well defined but simple real-time systems. The results give the base for successful determination of tool quality and making preliminary conclusions on potential qualification.
A framework for concrete reputation-systems with applications to history-based access control
Authors: Karl Krukow, Mogens Nielsen, Vladimiro Sassone
Venue: Proceedings of the 12th ACM conference on Computer and communications security (2005)

In a reputation-based trust-management system, agents maintain information about the past behaviour of other agents. This information is used to guide future trust-based decisions about interaction. However, while trust management is a component in security decision-making, many existing reputation-based trust-management systems provide no formal security-guarantees. In this extended abstract, we describe a mathematical framework for a class of simple reputation-based systems. In these systems, decisions about interaction are taken based on policies that are exact requirements on agents' past histories. We present a basic declarative language, based on pure-past linear temporal logic, intended for writing simple policies. While the basic language is reasonably expressive (encoding e.g. Chinese Wall policies) we show how one can extend it with quantification and parameterized events. This allows us to encode other policies known from the literature, e.g., `one-out-of-k'. The problem of checking a history with respect to a policy is efficient for the basic language, and tractable for the quantified language when policies do not have too many variables.
Operator-adapted finite element wavelets: theory and applications to a posteriori error estimation and adaptive computational modeling
Authors: Raghunathan Sudarshan
Venue:  (2005)

We propose a simple and unified approach for a posteriori error estimation and adaptive mesh refinement in finite element analysis using multiresolution signal processing principles. Given a sequence of nested discretizations of a domain we begin by constructing approximation spaces at each level of discretization spanned by conforming finite element interpolation functions. The solution to the virtual work equation can then be expressed as a telescopic sum consisting of the solution on the coarsest mesh along with a sequence of error terms denoted as two-level errors. These error terms are the projections of the solution onto complementary spaces that are scale-orthogonal with respect to the inner product induced by the weak-form of the governing differential operator. The problem of generating a compact, yet accurate representation of the solution then reduces to that of generating a compact, yet accurate representation of each of these error components. This problem is solved in three steps: (a) we first efficiently construct a set of scale-orthogonal wavelets that form a Riesz stable basis (in the energy-norm) for the complementary spaces; (b) we then efficiently estimate the contribution of each wavelet to the two-level error and finally (c) we select a subset of the wavelets at each level to preserve and solve exactly for the corresponding coefficients. Our approach has several advantages over a posteriori error estimation and adaptive refinement techniques in vogue in finite element analysis. First, in contrast to the true error, the two-level errors can be estimated very accurately even on coarse meshes. Second, mesh refinement is carried out by the addition of wavelets rather than element subdivision. This implies that the technique does not have to directly deal with the handling of irregular vertices. Third, the error estimation and adaptive refinement steps use the same basis. Therefore, the estimates accurately predict how much the error will reduce upon mesh refinement. Finally, the proposed approach naturally and easily accommodates error estimation and adaptive refinement based on both the energy norm as well any bounded linear functional of interest (i.e., goal-oriented error estimation and adaptivity). We demonstrate the application of our approach to the adaptive solution of second and fourth-order problems such as heat transfer, linear elasticity and deformation of thin plates. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
A Flexible Video Streaming System for Urban Traffic Control
Authors: Manuel Esteve, Carlos E. Palau
Venue: IEEE MultiMedia (2006)

This article discusses an innovative system for traffic management that is presently under installation in the city of Valencia. Key features of the system are to exploit open source software components and use MPEG-4 video streaming over an Internet protocol. The video streaming management is particularly sophisticated, resulting in a flexible, efficient, and reliable service. Another important element is the communication network design. In this case, the main issues to address were flexibility, scalability, and fault tolerance. The authors successfully addressed these issues by using a hierarchical network structure, with physical redundancy, based on spanning tree protocols. The overall system is specifically for urban traffic control, but some of its characteristics could make it easily reconfigurable to different contexts and environments.
Parallel programming
Authors: Ian D. Chivers, Jane Sleightholme
Venue: ACM SIGPLAN Fortran Forum (2005)

The Fortran language has been standardised a number of times&bull; Fortran 66&bull; Fortran 77&bull; Fortran 90&bull; Fortran 95&bull; Fortran 2003and Fortran 2008 is work in progress.
Symbolic Signatures for Deformable Shapes
Authors: Salvador Ruiz-Correa Linda G. Shapiro
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2006)

Recognizing classes of objects from their shape is an unsolved problem in machine vision that entails the ability of a computer system to represent and generalize complex geometrical information on the basis of a finite amount of prior data. A practical approach to this problem is particularly difficult to implement, not only because the shape variability of relevant object classes is generally large, but also because standard sensing devices used to capture the real world only provide a partial view of a scene, so there is partial information pertaining to the objects of interest. In this work, we develop an algorithmic framework for recognizing classes of deformable shapes from range data. The basic idea of our component-based approach is to generalize existing surface representations that have proven effective in recognizing specific 3D objects to the problem of object classes using our newly introduced symbolic-signature representation that is robust to deformations, as opposed to a numeric representation that is often tied to a specific shape. Based on this approach, we present a system that is capable of recognizing and classifying a variety of object shape classes from range data. We demonstrate our system in a series of large-scale experiments that were motivated by specific applications in scene analysis and medical diagnosis.