Search results for " computing"

Session details: Track 5: estimation of distribution algorithms

2009

CVS: Using VLANs to Counteract the Effect of Topology Changes in Quasi-Static Mesh Access Networks

2006

Mesh networks are candidate to play the role of switched Ethernet LANs over extended areas and with a sensibly higher flexibility. Actually, mesh networks can exploit both Ethernet and wireless technologies, e.g. Wi-Fi and/or free-space optical links, to provide a high degree of redundancy in an access network, and to provide users with powerful means to connect with each other. By using such technologies, the mesh topology remains stable for hours, so that the mesh topology can be considered quasi-static. However, large meshes require a heavy overhead in the network control plane as for the management of end-to-end paths, which can change due to mobility of users and due to occasional fail…

Dynamic QoS management for multimedia real-time transmission in industrial environments

2007

The use of multimedia within industrial applications has become commonplace, targetting improved process monitoring and machine vision. In both cases, the multimedia information is commonly distributed and subject to time constraints that must be met across networks while avoiding untolerable interference over typical control flows. This can be achieved with Constant Bit-Rate (CBR) channels, typically supported by real-time protocols. However, the compressors used to reduce the amount of information to transfer generate Variable Bit-Rate (VBR) patterns. Adapting a VBR source to a CBR channel requires specific care in order to avoid wasting channel bandwidth or dropping video frames. This pa…

Review of IEEE 802.22 and IEC 61850 for real-time communication in Smart Grid

2015

Real time data communication in Smart Grid is a big challenge due to its vastness and complexities. Wireless Regional Area Network (WRAN) - IEEE 802.22 permits opportunistic use of television white space (TVWS) by secondary user, if it is not being utilized by primary user. This standard has the potential to transfer big data of smart grid in real time to control center. The IEC 61850 is the standard for electrical substation automation that uses TCP/IP for data transfer among different ‘intelligent electronic devices’ (IEDs). IEC 61850 consists of different message types which belong to different performance classes that are mapped to different communication protocols. The different perfor…

LSOM: A Link State protocol Over MAC addresses for metropolitan backbones using Optical Ethernet switches

2003

This paper presents a new protocol named "Link State Over MAC" (LSOM) for Optical Ethernet switches to allow the use of active loop topologies, like meshes, in Metropolitan Area Networks (MAN) or even Wide Area Networks (WAN) backbone. In this respect, LSOM is an alternative to a ring topology as proposed in draft IEEE 802.17 Resilient Packet Ring (RPR) or a tree topology using IEEE802. 1D Rapid Spanning Tree Protocol (RSTP). LSOM provides higher scalability and is able to achieve better bandwidth utilization and lower latency than RSTP and RPR. Simulation results for 4-node and 9-node topologies show that LSOM can improve throughput over RPR by a factor of up to 1.7. Furthermore, full free…

CUDA-Accelerated Alignment of Subsequences in Streamed Time Series Data

2014

Euclidean Distance (ED) and Dynamic Time Warping (DTW) are cornerstones in the field of time series data mining. Many high-level algorithms like kNN-classification, clustering or anomaly detection make excessive use of these distance measures as subroutines. Furthermore, the vast growth of recorded data produced by automated monitoring systems or integrated sensors establishes the need for efficient implementations. In this paper, we introduce linear memory parallelization schemes for the alignment of a given query Q in a stream of time series data S for both ED and DTW using CUDA-enabled accelerators. The ED parallelization features a log-linear calculation scheme in contrast to the naive …

The Neural Bases of Event Monitoring across Domains: a Simultaneous ERP-fMRI Study.

2017

The ability to check and evaluate the environment over time with the aim to detect the occurrence of target stimuli is supported by sustained/tonic as well as transient/phasic control processes, which overall might be referred to as event monitoring. The neural underpinning of sustained attentional control processes involves a fronto-parietal network. However, it has not been well-defined yet whether this cortical circuit acts irrespective of the specific material to be monitored and whether this mediates sustained as well as transient monitoring processes. In the current study, the functional activity of brain during an event monitoring task was investigated and compared between two cognit…

Universal natural shapes: From unifying shape description to simple methods for shape analysis and boundary value problems

2012

Gielis curves and surfaces can describe a wide range of natural shapes and they have been used in various studies in biology and physics as descriptive tool. This has stimulated the generalization of widely used computational methods. Here we show that proper normalization of the Levenberg-Marquardt algorithm allows for efficient and robust reconstruction of Gielis curves, including self-intersecting and asymmetric curves, without increasing the overall complexity of the algorithm. Then, we show how complex curves of k-type can be constructed and how solutions to the Dirichlet problem for the Laplace equation on these complex domains can be derived using a semi-Fourier method. In all three …

A study of mobility and reachability in ad hoc networks using stochastic activity networks

2006

The integration of ad-hoc networks into real environments is now becoming more and more common and supervision and control systems are no exception. The efficiency of the communication in these networks as well as various other factors, are governed by the working area, the number of nodes, mobility, transmission power, etc. In this paper, the mobility and reachability of mobile nodes appearing spontaneously in a large installation such as can be found in a water purification system are studied. These nodes form an ad-hoc network and communicate between each other in order to finally reach a fixed node which can offer them information from the rest of the system in real time or act as a gat…

Two Levels SPF-Based System to Interconnect Partially Decentralized P2P File Sharing Networks

2005

Partially decentralized P2P (PDP2P) networks are a subset of P2P networks. Roles of nodes are different according to their functionality in the network. Nowadays, there are many PDP2P networks, with different characteristics. It is necessary to find a way to join those autonomous networks. We have not found any interconnection system, so in this article we present a new hierarchical system for interconnecting peers from different PDP2P networks. It will allow sharing data, content and resources between networks. It can be employed between sensor networks, P2P networks, and generally, overlay networks. Oldest superpeers or brokers with higher bandwidth in the PDP2P network will belong to hig…