Search results for "NETWORKING"
showing 10 items of 1776 documents
A tunnel magnetoresistive effect wattmeters-based wireless sensors network
2017
Abstract In the present work a wireless sensors network (WSN) for smart energy metering is presented using the ZigBee protocol as the communication link. Each network node process the electrical power by means of a Wheatstone bridge sensor based on the tunnel magnetoresistive (TMR) effect working as analogue multiplier. The electrical power is acquired and processed by a digital signal processor that extracts various parameters of interest like current and voltage load, active power and power factor by means of Fourier analysis. All the obtained electrical parameters at each node are served and shown in a web page that can be easily accessed by authorized users.
Fuzzy topology discovery protocol for SDN-based wireless sensor networks
2017
Abstract The growing trend in pervasive systems forces traditional wireless sensor networks to deal with new challenges, such as dynamic application requirements and heterogeneous networks. One of the latest paradigms in this area is software defined wireless sensor network. According to the paradigm, the networks take care of managing topological information and forwarding decisions using a bipartite architecture in which a control plane decides the forwarding policies and the data plane (i.e. ordinary sensor nodes) executes them. Unfortunately, in highly dynamic networks, this approach generates an overhead of control packet exchange between the ordinary nodes and the control plane, that …
A Novel Wireless Sensor Network for Electric Power Metering
2015
Wireless sensor network with lightweight and efficient communication infrastructures are today a great interest, both at research and industrial level, as they are the basis for reliable monitoring services. Mesh networks are ideal candidates in this scenario, as they can be very fault-tolerant. After introducing wireless network systems requirements, we show the design of a mesh network routing protocol based on AODV schemas. Its implementation runs on top of low-cost off-the-shelf components, and allowed us to build a custom power meter wireless sensor node.
Narrowband digital filtering with random frequency hopping spread spectrum
2014
International audience; In digital signal filtering, channels with narrow bandwidth need high order digital filter to be selected without introducing modulation errors. If a carrier randomly switches from a channel to another as in military applications, or some civilian communication standards, it is necessary to detect and estimate these jumps before transposing and analyzing signals in the baseband. This paper presents a real time solution to filter narrow band signals with random frequency hopping spread spectrum. The proposed method is based on three steps. Firstly, the detection of Signal Frequency Hopping (SFH) using the Fast Fourier Transform (FFT), an algorithm to estimate the Domi…
Charging management of grid integrated battery for overcoming the intermittency of RE sources
2016
Grid integration of distributed generation (DG) systems with energy storage system can help not only in increasing the more penetration of DG systems into the network but it is also going to help in improving the power system dynamics, stability and control as well as helping in demand side management. In this work, a method for integrating an energy storage with the grid which can provide the prescribed active and reactive power to the grid is presented. The main objective is to ensure a high state of charge (SOC) of the battery with the innovative control system for taking part in power system control. Active and reactive power dispatching using a bi-directional DC-DC converters and a vol…
New theoretical solution of the outflow process with a weir with complex shape
2016
AbstractIn this paper, the outflow process of a weir with an irregular shape is studied using dimensional analysis and the incomplete self-similarity theory. The new unique stage–discharge relationship, which is deduced theoretically, represents a novel and comprehensive equation to describe the weir outflow process for a full range of flow and different geometric variables of weirs, including finite-crested weirs, broad-crested weirs with positive or negative crest slope, broad-crested weirs with an upstream, downstream, or both upstream and downstream crest ramps, and, triangular weirs with an upstream or downstream ramp. Finally the proposed stage–discharge relationship is calibrated usi…
A Wireless Acoustic Array System for Binaural Loudness Evaluation in Cities
2017
Networks of acoustic sensors are being deployed in smart cities to continuously monitor noise levels. In this paper, a novel acoustic sensor device is designed for binaural loudness evaluation, in a standalone platform. The audio is acquired from an array of microphones and a binaural signal is synthesized by a direction-of-arrival algorithm and a head-related transfer function. Hardware setup and software algorithms are presented and the results are discussed. Finally, the tests conducted in an early deployment show the feasibility of using the device to carry out large temporal and spatial sampling for the evaluation of binaural loudness.
A Comparative Analysis of the Reliability of Simple and Two-Level Checkpointing Techniques in two Different Distributed Industrial Control System Arc…
2003
In Distributed industrial control systems it is necessary to guarantee certain reliability level. In this sense, Checkpointing and Rollback techniques offer interesting possibilities to achieve fault tolerance without appreciable cost and complexity increment. Several Checkpointing techniques have been proposed. Most of them suppose the presence of stable storage in the system. But distributed industrial control systems usually do not dispose of this kind of storage. So, another storage strategy has to be employed. If Checkpoints were locally stored (Simple Checkpointing), the system tolerates only transient faults. If Checkpoints were locally, at the same node, and, additionally, at anothe…
Energy Harvesting-Aware Backoff Algorithms for Distributed Device-to-Device Communication
2016
Due to limited energy capacity in mobile devices, energy harvesting is regarded as a promising technology for lifetime extension in device-to-device (D2D) communication. However, medium access control (MAC) protocols designed for D2D communication intrinsically do not consider the existence of harvested energy. In this paper we study four backoff (BO) algorithms, among which one algorithm is proposed to enhance the BO selection based on energy harvesting rate and residual energy of devices. Simulations are performed in order to assess how the proposed algorithm can extend the lifetime of a D2D communication network as well as to provide fair channel access opportunities among devices.
Development of Diagnostic Systems for the Fault Tolerant Operation of Micro-Grids
2010
The progressive penetration level of Distributed Generation (DG) is destined to cause deep changes in the existing distribution networks no longer considered as passive terminations of the whole electrical system. A possible solution is the realization of small networks, namely the Micro-Grids, reproducing in themselves the structure of the main production and distribution of the electrical energy system. In order to gain an adequate reliability level of the micro-grids the individuation and the management of the faults with the goal of maintaining the micro-grid operation (fault tolerant operation) is quite important. In the present paper after the introduction of the aims of several diagn…