ppxscal/embedding_network huggingface dataset:
Guest Editors' Introduction Performance Evaluation of Multiple Processor Systems
Venue: IEEE Transactions on Computers (1983)

PERFORMANCE evaluation means to study, to analyze, and to optimize the flow of data and control information in computer systems. In doing so, the main objectives are to formally describe the real behavior of computers, to define and determine characteristic performance measures, and to develop tools for the design of optimal hardware structures and system software. 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
Modeling Analysis and Improvement for Free-Riding on BitTorrent-like File Sharing Systems
Authors: Jiadi Yu, Minglu Li, Jie Wu
Venue: Proceedings of the 2007 International Conference on Parallel Processing Workshops (2007)

BitTorrent has emerged as a very popular peer-topeer file sharing system, which uses an embedded set of incentive mechanisms to encourage contribution and prevent free-riding. However, the capability BitTorrent has of preventing free-riding needs further study. In this paper, we present a fluid model with two different classes of peers to capture the effect of free-riding on BitTorrent-like systems. With the model, we find that BitTorrent's incentive mechanism is successful in preventing free-riding in a system without seeds, but may not succeed in producing a disincentive for free-riding in a system with a high number of seeds. The reason for this is that BitTorrent does not employ an effective mechanisms for seeds to effectively guard against free-riding. Therefore, we propose a seed bandwidth allocation strategy for the BitTorrent system to reduce the effect of seeds on free-riding. Finally, simulation results are given, which validate what we have found in our analysis and demonstrate the effectiveness of the proposed strategy.
The Relation of CMM and Software Lifecycle Model
Authors: Zhang Sen, Yao Zheng
Venue: Proceedings of the Eighth ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing - Volume 03 (2007)

CMM and Software Life Cycle Model are both widely used in the IT industry. Based on the analysis of CMM and major software life cycle models, the following points were investigated: (1) CMM and Software Life Cycle Model are both results of the process of software activities and they both focus on the process of software activities. To be specific, CMM is the result of the maturity stage, and Software Life Cycle Model is the result of the early stage. (2) Owing to different development backgrounds and different problems to resolve, Software Life Cycle Model focuses on engineering activities, while CMM focuses on non-engineering activities. (3) Though the CMM authors had tried to make CMM be independent of any certain software life cycle model, the originating era of CMM did leave CMM with the brand of the waterfall model.
Slot allocation using logical networks for TDM virtual-circuit configuration for network-on-chip
Authors: Zhonghai Lu, Axel Jantsch
Venue: Proceedings of the 2007 IEEE/ACM international conference on Computer-aided design (2007)

Configuring Time-Division-Multiplexing (TDM) Virtual Circuits (VCs) for network-on-chip must guarantee conflict freedom for overlapping VCs besides allocating sufficient time slots to them. These requirements are fulfilled in the slot allocation phase. In the paper, we define the concept of a logical network (LN). Based on this concept, we develop and prove theorems that constitute sufficient and necessary conditions to establish conflict-free VCs. Using these theorems, slot allocation for VCs becomes a procedure of computing LNs and then assigning VCs to different LNs. TDM VC configuration can thus be predictable and correct-by-construction. We have integrated this slot allocation method into our multi-node VC configuration program and applied the program to an industrial application.
Reliability and Scheduling on Systems Subject to Failures
Authors: Mourad Hakem, Franck Butelle
Venue: Proceedings of the 2007 International Conference on Parallel Processing (2007)

This paper presents a new bi-objective greedy heuristic for scheduling parallel applications on heterogeneous distributed computing systems. The proposed algorithm which is called BSA (Bi-objective Scheduling Algorithm) takes into account not only the time makespan but also the failure probability of the application. Since it is not usually possible to achieve the two conflicting objectives (performance and reliability) simultaneously, a bi-objective compromise function is introduced. BSA has a low time complexity of O(e|P|+v log \omega), where e and v are respectively the number of edges and tasks in the task graph of the application. |P| is the number of machines (processors) in the system and \omega is the width of the task graph. Experimental results show the performance of the proposed algorithm.
Fourier spectral and wavelet solvers for the incompressible Navier-Stokes equations with volume-penalization: Convergence of a dipole-wall collision
Authors: G. H. Keetels, U. D'Ortona, W. Kramer, H. J. H. Clercx, K. Schneider, G. J. F. van Heijst
Venue: Journal of Computational Physics (2007)

In this study, we use volume-penalization to mimic the presence of obstacles in a flow or a domain with no-slip boundaries. This allows in principle the use of fast Fourier spectral methods and coherent vortex simulation techniques (based on wavelet decomposition of the flow variables) to compute turbulent wall-bounded flow or flows around solid obstacles by simply adding one term in the equation. Convergence checks are reported using a recently revived, and unexpectedly difficult dipole-wall collision as a benchmark computation. Several quantities, like the vorticity isolines, truncation error, kinetic energy and enstrophy are inspected for a collision of a dipole with a no-slip wall and compared with available benchmark data obtained with a standard Chebyshev pseudospectral method. We quantify the possible deteriorating effects of the Gibbs phenomenon present in the Fourier based schemes due to continuity restrictions of the penalized Navier-Stokes equations on the wall. It is found that Gibbs oscillations have a negligible effect on the flow evolution allowing higher-order recovery of the accuracy on a Fourier basis by means of postprocessing. An advantage of coherent vortex simulations, on the other hand, is that the degrees of freedom of the flow computation can strongly be reduced. In this study, we quantify the possible reduction of degrees of freedom while keeping the accuracy. For an optimal convergence scenario the penalization parameter has to scale with the number of Fourier and wavelet modes. In addition, an implicit treatment of the Darcy drag term in the penalized Navier-Stokes equations is beneficial since this allows one to set the time step independent from the penalization parameter without additional computational or memory requirements.
Modeling and Performance Evaluation of Hierarchical Job Scheduling on the Grids
Authors: Zhiguang Shan, Chuang Lin
Venue: Proceedings of the Sixth International Conference on Grid and Cooperative Computing (2007)

Job scheduling is a fundamental issue in achieving high performance on the Grids. In this paper, a hierarchical job scheduling architecture has been proposed for the Grids. The stochastic high-level Petri net (SHLPN) model of the proposed architecture and the refined model are presented. The job scheduling algorithms for an incoming job to be distributed to a waiting queue of any processor in any node of the Grid architecture is integrated by the node-selection algorithm at the global scheduler, the job-dispatching algorithm at the local scheduler, and job-scheduling algorithm at the processor scheduler. The integrated job scheduling policy is investigated using SHLPN performance analysis methods. The performance metrics concerned include the delay time of jobs in the Grid node and the response time perceived by the users. The numerical example shows the efficiency of the performance evaluation technique.
Indexing multiversion databases
Authors: Khaled Jouini, Geneviève Jomier
Venue: Proceedings of the sixteenth ACM conference on Conference on information and knowledge management (2007)

An efficient management of multiversion data with branched evolution is crucial for many applications. It requires database designers aware of tradeoffs among index structures and policies. This paper defines a framework and an analysis method for understanding the behavior of different indexing policies. Given data and query characteristics the analysis allows determining the most suitable index structure. The analysis is validated by an experimental study.
The Efficient and Complete Frequent Itemsets Mining of Association Rules
Authors: Xu-dong Song, Kun Zhai, Xiao-bing Liu
Venue: Proceedings of the Fourth International Conference on Fuzzy Systems and Knowledge Discovery - Volume 01 (2007)

How to generate the candidate itemsets, how to compute the supporting number of itemsets, how to reduce the size of candidate itemsets and how to decrease the scanning times of transaction databases, are four capital technique difficulties of association rules mining. In this paper, we have presented an new idea that transforms the data structure of transaction databases to the directed graph, and applies the directed itemsets graph to store the relevant information of frequent itemsets of transaction databases, and puts forward trifurcate linked list storage structure of directed itemsets graph, and provides mining algorithm of complete frequent itemsets based on the directed itemsets graph. So the four capital technique difficulties mentioned above are resolved efficiently.
The Role of Abstract Interpretation in Formal Methods
Venue: Proceedings of the Fifth IEEE International Conference on Software Engineering and Formal Methods (2007)

Abstract interpretation [3, 8] is a theory of sound approximation of mathematical structures, in particular those involved in the description of the behavior of computer systems. It allows the systematic derivation of sound methods and algorithms for approximating undecidable or highly complex problems in various areas of computer science (semantics, verification and proof, modelchecking, static analysis, program transformation and optimization, typing, software steganography, etc.). Its main current application is on the safety and security of complex hardware and software computer systems.
Integrating an Electron-Beam System into VLSI Fault Diagnosis
Authors: Teruo Tamama, Norio Kuji
Venue: IEEE Design Test (1986)

Using design data, the system can prepare a logic-state map for the device under test. The map draws top-layer connectionsin different colors according to their expected logic states so the map may be compared to the DUT image observed by the electron-beamtester. The system has successfully tested a 75K-transistor VLSI device.
Implementation and use of the PLT scheme Web server
Authors: Shriram Krishnamurthi, Peter Walton Hopkins, Jay Mccarthy, Paul T. Graunke, Greg Pettyjohn, Matthias Felleisen
Venue: Higher-Order and Symbolic Computation (2007)

The PLT Scheme Web Server uses continuations to enable a natural, console-like program development style. We describe the implementation of the server and its use in the development of an application for managing conference paper reviews. In the process of developing this application, we encountered subtle forms of interaction not directly addressed by using continuations. We discuss these subtleties and offer solutions that have been successfully deployed in our application. Finally, we present some details on the server's performance, which is comparable to that of the widely-used Apache Web server.
Efficient gathering of correlated data in sensor networks
Authors: Himanshu Gupta, Vishnu Navda, Samir Das, Vishal Chowdhary
Venue: ACM Transactions on Sensor Networks (TOSN) (2008)

In this article, we design techniques that exploit data correlations in sensor data to minimize communication costs (and hence, energy costs) incurred during data gathering in a sensor network. Our proposed approach is to select a small subset of sensor nodes that may be sufficient to reconstruct data for the entire sensor network. Then, during data gathering only the selected sensors need to be involved in communication. The selected set of sensors must also be connected, since they need to relay data to the data-gathering node. We define the problem of selecting such a set of sensors as the connected correlation-dominating set problem, and formulate it in terms of an appropriately defined correlation structure that captures general data correlations in a sensor network. We develop a set of energy-efficient distributed algorithms and competitive centralized heuristics to select a connected correlation-dominating set of small size. The designed distributed algorithms can be implemented in an asynchronous communication model, and can tolerate message losses. We also design an exponential (but nonexhaustive) centralized approximation algorithm that returns a solution within O(log n) of the optimal size. Based on the approximation algorithm, we design a class of centralized heuristics that are empirically shown to return near-optimal solutions. Simulation results over randomly generated sensor networks with both artificially and naturally generated data sets demonstrate the efficiency of the designed algorithms and the viability of our technique&mdash;even in dynamic conditions.
A 3-Dimensional Relevance Model for Collaborative Software Engineering Spaces
Authors: Inah Omoronyia, John Ferguson, Marc Roper, Murray Wood
Venue: Proceedings of the International Conference on Global Software Engineering (2007)

Today's large software projects are often characterised by distributed environments with numerous developers separated in space and/or time. This separation means that the common understanding and tacit knowledge that is a feature of closely colocated project teams is very hard to come by. As a consequence, relatively simple tasks such as identifying functionally related modules or finding individuals who are experts in aspects of the system become more challenging and time-consuming. This paper presents a Continuum of Relevance Index (CRI) model that uses information gathered from developer IDE interactions to generate orderings of relevant tasks, project artefacts and developers. A case study is used to demonstrate how the model can be used to attain a shared knowledge and common understanding of the extent to which tasks, artefacts and developers are relevant in a group development work context.
Perceptive Vision for Headline Localisation in Bangla Handwritten Text Recognition
Authors: A. Lemaitre, B. B. Chaudhuri, B. Couasnon
Venue: Proceedings of the Ninth International Conference on Document Analysis and Recognition - Volume 02 (2007)

In this paper, we propose to give tools for Bangla hand- writing recognition. We present a mechanism to segment documents into text lines and words, and more specifically to detect headline position in each word. Indeed, this head- line is an horizontal line on the upper part of most of char- acters, which is characteristic of Bangla writing. Its locali- sation is a new approach that can improve text recognition quality. This headline is detected into words inside text lines thanks to a notion of perceptive vision: at a certain dis- tance, text lines appear as line-segments that give the global orientation of words. Watching closer may help to give the exact position of the headline. Consequently, this work is mainly based on applying a segment extractor at different image resolutions and combining extracted information in order to compute the headlines. Our line-segment extractor is based on Kalman filtering.
An Efficient Hybrid P2P Incentive Scheme
Authors: Zhitao Guan, Muhammad Hanif Durad, Yuanda Cao, Liehuang Zhu
Venue: Proceedings of the Eighth ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing - Volume 03 (2007)

P2P systems have suffered a lot from free riding problem i.e. some participants consume more resources than they contribute. In order to deal with this problem efficiently, an incentive model based on peer credit has been proposed. Each peer in this model is a credit entity. Through introducing reward method to the model, peers will allocate resources according to the credits of requesting peers to maximize their own credits. A backtracking algorithm has been suggested to solve the issue of maximizing credit rewards. To avoid inflation of the credit, attenuation method is introduced. The scheme how to apply the credit model in hybrid P2P networks has also been elaborated in this work. The experimental results show that the model can effectively control free riding and improve efficiency of the system.
Towards Path-Sensitive Points-to Analysis
Authors: Tobias Gutzmann, Jonas Lundberg, Welf Lowe
Venue: Proceedings of the Seventh IEEE International Working Conference on Source Code Analysis and Manipulation (2007)

Points-to analysis is a static program analysis aiming at analyzing the reference structure of dynamically allocated objects at compile-time. It constitutes the basis for many analyses and optimizations in software engineering and compiler construction. Sparse program representations, such as Whole Program Points-to Graph (WPP2G) and Points-to SSA (P2SSA), represent only dataflow that is directly relevant for points-to analysis. They have proved to be practical in terms of analysis precision and efficiency. However, intra-procedural control flow information is removed from these representations, which sacrifices analysis precision to improve analysis performance. We show an approach for keeping control flow related information even in sparse program representations by representing control flow effects as operations on the data transferred, i.e., as dataflow information. These operations affect distinct paths of the program differently, thus yielding a certain degree of pathsensitivity. Our approach works with both WPP2G and P2SSA representations. We apply the approach to P2SSA-based and flow-sensitive points-to analysis and evaluate a context-insensitive and a context-sensitive variant. We assess our approach using abstract precision metrics. Moreover, we investigate the precision improvements and performance penalties when used as an input to three source-code-level analyses: dead code, cast safety, and null pointer analysis.
A Novel Approach to Fine-grained Content-based Access Control for Video Databases
Authors: Nguyen Anh Thy Tran, Tran Khanh Dang
Venue: Proceedings of the 18th International Conference on Database and Expert Systems Applications (2007)

The growing amount of multimedia data available to the average user has reached a critical phase where methods for indexing, searching, and efficient retrieval are expressly needed to manage the information load. In this paper, we present a hybrid video database model which is a combination of the hierarchical video database model and annotations using. In particular, we extend the original hierarchical indexing mechanism to add frames and salient objects as the lowest granularity level in the video tree with the aim to support multi-level access control. In conjunction, with the use of annotations, we give users more solutions to query for their interesting videos based on the video contents (content-based retrieval). In addition, we also tailor the original database access control model to fit the characteristics of video data. Our updated model supports both multiple access control policies, means a user may be affected by multiple polices, and multilevel access control, means an authorization may be specified at any video levels.
A Cross-Authentication Model for Heterogeneous Domains in Active Networks
Authors: Qiong Chen, Zhongwen Li, Shui Yu
Venue: Proceedings of the 2007 IFIP International Conference on Network and Parallel Computing Workshops (2007)

Active network has been applied widely recently. The current status is that there is coexistence of multi- PKI in heterogeneous domains. We have noticed there are little work has been done in cross-certification for heterogeneous domains. In this paper, we propose a cross-authentication model for the raised issue. Our system implements mutual entity authentication among heterogeneous domains based on Cert-PKI and IDPKI. The theoretical analysis and the preliminary experiments demonstrate that the proposed system possesses the properties of high security and stability.
The use of invariant features for object recognition from a single image
Authors: M. Zaki, M. M. Abulwafa
Venue: Journal of Intelligent Fuzzy Systems: Applications in Engineering and Technology (2002)

In this work, we present effective methods for detecting and representing invariant features of three dimensional (3-D) objects from single images. Our methods are independent of the viewpoint position, and can be used in the recognition process of 3-D objects. The invariant features are; shapes of the object surfaces, organization of the surfaces within the object, and the new feature which is shapes of privileged surfaces (PS) of the object. Also we explain the way these features are represented and matched against stored model of the object. Our work is built around the knowledge based approach and depends on the fact that while it is true that the appearance of a 3-D object may change completely as it is viewed from different viewpoints, it is also true that many aspects of the object projection remain invariant over large ranges of viewpoints. This approach is different from the other approach that derives or calculates depth information and orientations of surfaces using more than one image of the object, or the approach that statistically detects and matchs the object features. The main contribution of our work is the introduction of privileged surface of 3-D object which plays an important role in the recognition process. Also we introduce heuristic methods for detecting shapes of surfaces, object organization, object & model representations and matching. The idea of matching privileged surfaces reduces the ambiguity that may arise due to limited visibility of the object surfaces (existence of hidden surfaces) when matching features of both the image and the model. Also matching privileged surfaces reduces the need of detecting and matching orientations of surfaces. This approach has been applied to 3-D objects which are bounded by planar surfaces. However, the work can be extended in a straightforward manner to support 3-D objects that are bounded by curved surfaces.
GoSh
Authors: Andrea Caprera, Barbara Lazzari, Alessandra Stella, Ivan Merelli, Alexandre R. Caetano, Paola Mariani
Venue: Bioinformatics (2007)

Summary: The GoSh database is a collection of 58 990 Capra hircus and Ovis aries expressed sequence tags. A perl pipeline was prepared to process sequences, and data were collected in a MySQL database. A PHP-based web interface allows browsing and querying the database. Putative single nucleotide polymorphism (SNP) detection, as well as search to repeats were performed, and links to external related resources were provided. Sequences were annotated against three different databases and an algorithm was implemented to create statistics of the distribution of retrieved homologous ontologies in the Gene Ontology categories. The GoSh database is a repository of data and links related to goat and sheep expressed genes. Availability: The GoSh database is available at http://www.itb.cnr.it/gosh/ Contact: andrea.caprera@tecnoparco.org