Distributed Computing

Insertion and Querying Mechanism for a Distributed XML Database System

by Shrisha Rao

Abhinandan M Kulkarni, Janani Thirunavukkarasu, Parvathy S Pillai, Sneha Somanath Sulegai, and Shrisha Rao.  ACM Compute 2012, Pune, India, January 2012.

XML files are ideal for describing semi structured data. The advent of native XML databases has enhanced storage of a... more XML files are ideal for describing semi structured data. The advent of native XML databases has enhanced storage of a large number of XML files preserving the hierarchical format. The challenge is to serve and access XML data from geographically distributed native XML databases. In this paper, we discuss the modus operandi for insertion and querying of data in a location transparent manner in decentralised networks. We present the design for a cluster based architecture where query processing is achieved using distributed hash tables. A bulk insertion method has been employed for insertion of XML data. The proposed design was implemented on eXist-db, a native XML database engine. Experiments were conducted and the effectiveness of the proposed design was evaluated.

Distributed Systems Course Project: Consensus with Failure Detector

by Mattia Avancini

Self-stabilizing Algorithms in DAG Structured Networks

by Sebastien Tixeuil

An Overview of Existing Tools for Fault-Injection and Dependability Benchmarking in Grids

by Sebastien Tixeuil

GridMAP-A Solution for Monitoring, Analysing and Predicting Network Performance and Resource Availability in Grids

by Yehia El-khatib

Providing grid schedulers with passive network measurements

by Yehia El-khatib

Juno: Reconfigurable Middleware for Heterogeneous Content Networking

by Yehia El-khatib

Co-authored with Gareth Tyson, Andreas Mauthe, and Thomas Plagemann

CORBA, DCOM E JAVARMI - Uma Análise Comparativa

by Vitor Roque

ROQUE, Vitor Manuel Gomes ;  OLIVEIRA, José Luís  - CORBA, DCOM E JAVARMI - UMA ANÁLISE COMPARATIVA . Ingenium . , vol. , n.º 46  (Mar. 2000) . p. 87-91. Portuguese text.

Efficient Mobile Querying of Distributed RDF Sources

by Beat Signer

Elien Paret, William Van Woensel, Sven Casteleyn, Beat Signer and Olga De Troyer, Proceedings of ESWC 2011 (Poster), 8th Extended Semantic Web Conference, Heraklion Greece, May 2011

WiGiTGroup-VisionandScopeVersion0.1McKnight3.27.2012

by Lee McKnight

L. Magnani (2006). Multimodal abduction. External semiotic anchors and hybrid representations

by Lorenzo Magnani

Logic Journal of the IGPL 14(2): 107-136.

Our brains make up a series of signs and are engaged in making or manifesting or reacting to a series of signs:... more Our brains make up a series of signs and are engaged in making or manifesting or reacting to a series of signs: through this semiotic activity they are at the same time engaged in “being minds” and so in thinking intelligently. An important effect of this semiotic activity of brains is a continuous process of “externalization of the mind” that exhibits a new cognitive perspective on the mechanisms underling the semiotic emergence of abductive processes of meaning formation. To illustrate this process I will take advantage of the analysis
of some aspects of the cognitive interplay between internal and external representations. I consider this interplay critical in analyzing the relation between meaningful semiotic internal resources and devices and their dynamical interactions with the externalized semiotic materiality suitably stocked in the environment. Hence, minds are material, “extended” and artificial in themselves. A considerable part of human abductive
thinking is occurring through an activity consisting in a kind of reification in the external environment (that originates what I call semiotic anchors) and a subsequent re–projection and reinterpretation through new configurations of neural networks and chemical processes. I also illustrate how this activity takes
advantage of hybrid representations and how it can nicely account for various processes of creative and selective abduction, bringing up the question of how multimodal aspects involving a full range of sensory modalities are important in hypothetical reasoning.

Availability in Globally Distributed Storage Systems

by Murray Stokely

Large-Scale Parallel Statistical Forecasting Computations in R

by Murray Stokely

2007_OSGEO_OSGeoJournal_vol2_GRASS_distrib

by Yann Chemin

The Manna Plug-In Architecture for Content-based Search of VM Clouds

by Wolfgang Richter

Modeling A Publish/Subscribe System As A Multi-Commodity Transportation Problem

by Shrisha Rao

6th Annual IEEE International Systems Conference (IEEE SysCon 2012), Vancouver, Canada, March 2012.

The publish/subscribe paradigm enables creation of loosely coupled dynamic systems with asynchronous communication... more The publish/subscribe paradigm enables creation of loosely coupled dynamic systems with asynchronous communication models but at the cost of unpredictable system behavior. Hence quality of service guarantees (QoS) are to be provided to bring in predictability in system behavior. There is a cost associated with providing the QoS guarantees and this cost needs to be reduced. In a publish/subscribe system, published information has to be delivered to a set of subscribers who have expressed interest in the publications. Optimal routing of information from producers of information to the consumers of information is critical to the performance of the publish/subscribe system. This paper proposes a strategy for routing of publications in a publish/subscribe system by modeling it as a multi commodity transportation problem. The proposed approach minimizes the cost of routing publications and also maintains the QoS guarantees.

Energy-Aware Scheduling of Distributed Systems Using Cellular Automata

by Shrisha Rao

6th Annual IEEE International Systems Conference (IEEE SysCon 2012), Vancouver, Canada, March 2012.

In today’s world of large distributed systems, the need for energy efficiency of individual components is comple-... more In today’s world of large distributed systems, the need for energy efficiency of individual components is comple- mented by the need for energy awareness of the complete system. Hence, energy-aware scheduling of tasks on systems has become very important. Our work addresses the problem of finding an energy-aware schedule for a given system which also satisfies the precedence constraints between tasks to be performed by the system. We present a method which uses cellular automata to find a near-optimal schedule for the system. The rules for cellular automata are learned using a genetic algorithm. Though the work presented in this paper is not limited to scheduling in computing environments only, the work is validated with a sample simulation on distributed computing systems, and tested with some standard program graphs.

On Harnessing Desktop Grids for Semi-Real Time 3D Rendering: A Case Study on POV-Ray

by Qusay F. Hassan

Co-authored with A. M. Riad A. E. Hassan
Published in Annals. Computer Science Series, Tome 9, Fasc. 2. December 2011

As is known, 3D rendering puts a huge burden both on computers and artists/programmers. This task is usually slow and... more As is known, 3D rendering puts a huge burden both on computers and artists/programmers. This task is usually slow and requires the use of computational clusters as well as the installation of expensive resources such as multi-processors/cores and optimized graphics processing units to the traditional computers to lessen this burden. Parallelizing the rendering task of complex frames and scenes can cut the total rendering time dramatically. Grid computing is one of the parallel computing paradigms that allow implementers to combine the power of networked computers into a virtual supercomputer. Desktop grids are a form of grid computing that allows enterprises to build grids out of the workstations they already have. This feature could enable enterprises to better utilize their computing resources in order to solve computationally-intensive problems in a quick and cost-effective manner. The purpose of this paper is to present how enterprises can build desktop grids in a Windows environment in order to enable semi-real time rendering for 3D models defined with POV-Ray. Algorithms, tools and technical details are presented for easy and efficient implementations.

On Utilization of Enterprise Grids in Mathematical Finance: A Case on Monte Carlo Options Pricing

by Qusay F. Hassan

Draft only.
Co-authored with A. M. Riad and A. E. Hassan

The Monte Carlo method is being increasingly used in fields like mathematical finance, engineering, physical sciences,... more The Monte Carlo method is being increasingly used in fields like mathematical finance, engineering, physical sciences, bioinformatics and moving making to solve problems where it is infeasible to use the deterministic method. The Monte Carlo simulation is a numerical computational technique which uses thousands or even millions of random values to solve complex problems. This makes the Monte Carlo technique slow and computer-intensive when used for options pricing. Therefore, financial firms are usually forced to deploy powerful hardware means such as supercomputers and computer clusters in order to perform the needed simulations. The ability to link the traditional computers and servers available at organizations to form a grid that acts as a supercomputer can enable both scientists and professionals to run their simulations without spending extra costs. In this paper we propose and implement an application for Monte Carlo methods for options pricing using the enterprise grids on the Windows environment. We also provide a comparison between the performance of our framework and the traditional model with an introduction to the future work.

Implementation and Evaluation of POV-Ray on Desktop Grids: Parallel Rendering of 3D Images and Animations

by Qusay F. Hassan

Co-authored with A. M. Riad and A. E. Hassan
Published in Annals. Computer Science Series, Tome 9, Fasc. 2. December 2011

This paper discusses the implementation details of a grid-based rendering framework for POV-Ray on desktop grids. Our... more This paper discusses the implementation details of a grid-based rendering framework for POV-Ray on desktop grids. Our goal is to present how enterprises can build desktop grids in Windows environment in order to enable semi-real time rendering for 3D models, both images and animations, defined with POV-Ray. Algorithms, code and technical details are given for easy and efficient implementations. We think this work could be useful for both researchers and developers who are interested in the grid computing technology and its applications.