197 research outputs found
A comparative study of clusterhead selection algorithms in wireless sensor networks
In Wireless Sensor Network, sensor nodes life time is the most critical
parameter. Many researches on these lifetime extension are motivated by LEACH
scheme, which by allowing rotation of cluster head role among the sensor nodes
tries to distribute the energy consumption over all nodes in the network.
Selection of clusterhead for such rotation greatly affects the energy
efficiency of the network. Different communication protocols and algorithms are
investigated to find ways to reduce power consumption. In this paper brief
survey is taken from many proposals, which suggests different clusterhead
selection strategies and a global view is presented. Comparison of their costs
of clusterhead selection in different rounds, transmission method and other
effects like cluster formation, distribution of clusterheads and creation of
clusters shows a need of a combined strategy for better results.Comment: 12 pages, 3 figures, 5 tables, Int JournaL, International Journal of
Computer Science & Engineering Survey (IJCSES) Vol.2, No.4, November 201
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Performance Analysis of Cluster Based Communication Protocols for Energy Efficient Wireless Sensor Networks. Design, Analysis and Performance Evaluation of Communication Protocols under Various Topologies to Enhance the Lifetime of Wireless Sensor Networks.
Sensor nodes are deployed over sensing fields for the purpose of monitoring certain
phenomena of interest. The sensor nodes perform specific measurements, process the
sensed data, and send the data to a base station over a wireless channel. The base station
collects data from the sensor nodes, analyses this data, and reports it to the users.
Wireless sensor networks are different from traditional networks, because of the
following constraints. Typically, a large number of sensor nodes need to be randomly
deployed and, in most cases, they are deployed in unreachable environments; however,
the sensor nodes may fail, and they are subject to power constraints.
Energy is one of the most important design constraints of wireless sensor networks.
Energy consumption, in a sensor node, occurs due to many factors, such as: sensing the
environment, transmitting and receiving data, processing data, and communication
overheads. Since the sensor nodes behave as router nodes for data propagation, of the
other sensor nodes to the base station, network connectivity decreases gradually. This
may result in disconnected sub networks of sensor nodes. In order to prolong the
network¿s lifetime, energy efficient protocols should be designed for the characteristics
of the wireless sensor network. Sensor nodes in different regions of the sensing field can
collaborate to aggregate the data that they gathered.
Data aggregation is defined as the process of aggregating the data from sensor nodes to
reduce redundant transmissions. It reduces a large amount of the data traffic on the
network, it requires less energy, and it avoids information overheads by not sending all
of the unprocessed data throughout the sensor network. Grouping sensor nodes into
clusters is useful because it reduces the energy consumption. The clustering technique
can be used to perform data aggregation. The clustering procedure involves the selection
of cluster heads in each of the cluster, in order to coordinate the member nodes. The
cluster head is responsible for: gathering the sensed data from its cluster¿s nodes,
aggregating the data, and then sending the aggregated data to the base station.
An adaptive clustering protocol was introduced to select the heads in the wireless sensor
network. The proposed clustering protocol will dynamically change the cluster heads to
obtain the best possible performance, based on the remaining energy level of sensor
nodes and the average energy of clusters. The OMNET simulator will be used to present
the design and implementation of the adaptive clustering protocol and then to evaluate
it.
This research has conducted extensive simulation experiments, in order to fully study
and analyse the proposed energy efficient clustering protocol. It is necessary for all of
the sensor nodes to remain alive for as long as possible, since network quality decreases
as soon as a set of sensor nodes die. The goal of the energy efficient clustering protocol
is to increase the lifetime and stability period of the sensor network.
This research also introduces a new bidirectional data gathering protocol. This protocol
aims to form a bidirectional ring structure among the sensor nodes, within the cluster, in
order to reduce the overall energy consumption and enhance the network¿s lifetime. A bidirectional data gathering protocol uses a source node to transmit data to the base
station, via one or more multiple intermediate cluster heads. It sends data through
energy efficient paths to ensure the total energy, needed to route the data, is kept to a
minimum. Performance results reveal that the proposed protocol is better in terms of: its
network lifetime, energy dissipation, and communication overheads
Intelligent Sensor Networks
In the last decade, wireless or wired sensor networks have attracted much attention. However, most designs target general sensor network issues including protocol stack (routing, MAC, etc.) and security issues. This book focuses on the close integration of sensing, networking, and smart signal processing via machine learning. Based on their world-class research, the authors present the fundamentals of intelligent sensor networks. They cover sensing and sampling, distributed signal processing, and intelligent signal learning. In addition, they present cutting-edge research results from leading experts
Acta Universitatis Sapientiae - Electrical and Mechanical Engineering
Series Electrical and Mechanical Engineering publishes original papers and surveys in various fields of Electrical and Mechanical Engineering
Data Quality Management in Large-Scale Cyber-Physical Systems
Cyber-Physical Systems (CPSs) are cross-domain, multi-model, advance information systems that play a significant role in many large-scale infrastructure sectors of smart cities public services such as traffic control, smart transportation control, and environmental and noise monitoring systems. Such systems, typically, involve a substantial number of sensor nodes and other devices that stream and exchange data in real-time and usually are deployed in uncontrolled, broad environments.
Thus, unexpected measurements may occur due to several internal and external factors, including noise, communication errors, and hardware failures, which may compromise these systems quality of data and raise serious concerns related to safety, reliability, performance, and security. In all cases, these unexpected measurements need to be carefully interpreted and managed based on domain knowledge and computational models.
Therefore, in this research, data quality challenges were investigated, and a comprehensive, proof of concept, data quality management system was developed to tackle unaddressed data quality challenges in large-scale CPSs. The data quality management system was designed to address data quality challenges associated with detecting: sensor nodes measurement errors, sensor nodes hardware failures, and mismatches in sensor nodes spatial and temporal contextual attributes. Detecting sensor nodes measurement errors associated with the primary data quality dimensions of accuracy, timeliness, completeness, and consistency in large-scale CPSs were investigated using predictive and anomaly analysis models via utilising statistical and machine-learning techniques. Time-series clustering techniques were investigated as a feasible mean for detecting long-segmental outliers as an indicator of sensor nodes’ continuous halting and incipient hardware failures. Furthermore, the quality of the spatial and temporal contextual attributes of sensor nodes observations was investigated using timestamp analysis techniques.
The different components of the data quality management system were tested and calibrated using benchmark time-series collected from a high-quality, temperature sensor network deployed at the University of East London. Furthermore, the effectiveness of the proposed data quality management system was evaluated using a real-world, large-scale environmental monitoring network consisting of more than 200 temperature sensor nodes distributed around London.
The data quality management system achieved high accuracy detection rate using LSTM predictive analysis technique and anomaly detection associated with DBSCAN. It successfully identified timeliness and completeness errors in sensor nodes’ measurements using periodicity analysis combined with a rule engine. It achieved up to 100% accuracy in detecting potentially failed sensor nodes using the characteristic-based time-series clustering technique when applied to two days or longer time-series window. Timestamp analysis was adopted effectively for evaluating the quality of temporal and spatial contextual attributes of sensor nodes observations, but only within CPS applications in which using gateway modules is possible
AI Knowledge Transfer from the University to Society
AI Knowledge Transfer from the University to Society: Applications in High-Impact Sectors brings together examples from the "Innovative Ecosystem with Artificial Intelligence for Andalusia 2025" project at the University of Seville, a series of sub-projects composed of research groups and different institutions or companies that explore the use of Artificial Intelligence in a variety of high-impact sectors to lead innovation and assist in decision-making. Key Features Includes chapters on health and social welfare, transportation, digital economy, energy efficiency and sustainability, agro-industry, and tourism Great diversity of authors, expert in varied sectors, belonging to powerful research groups from the University of Seville with proven experience in the transfer of knowledge to the productive sector and agents attached to the Andalucía TECH Campu
AI Knowledge Transfer from the University to Society
AI Knowledge Transfer from the University to Society: Applications in High-Impact Sectors brings together examples from the "Innovative Ecosystem with Artificial Intelligence for Andalusia 2025" project at the University of Seville, a series of sub-projects composed of research groups and different institutions or companies that explore the use of Artificial Intelligence in a variety of high-impact sectors to lead innovation and assist in decision-making. Key Features Includes chapters on health and social welfare, transportation, digital economy, energy efficiency and sustainability, agro-industry, and tourism Great diversity of authors, expert in varied sectors, belonging to powerful research groups from the University of Seville with proven experience in the transfer of knowledge to the productive sector and agents attached to the Andalucía TECH Campu
Test and evaluation of a prototyped sensor-camera network for persistent intelligence, surveillance, and reconnaissance in support of tactical coalition networking environments
This thesis investigated the feasibility of deploying an integrated sensor-camera network in military and law enforcement applications. The system was built using entirely commercial-off-the-shelf technologies. The prototype used the unattended ground sensors combined with digital video surveillance cameras to provide accurate real-time situational awareness, persistent intelligence and remote security. A robust testing and evaluation plan was created to measure the system's performance based on specific metrics. The tests focused primarily on the capabilities of the sensor aspect of the network. Tests were conducted to determine the maximum detection range, probabilities of detection, maximum communications range, and battery life. Mathematical models were created to assist network planners. Additionally, the prototyped system was tested through field exercises as part of the Naval Postgraduate School's Coalition Operating Area Surveillance and Targeting System field demonstrations in California and northern Thailand. Although the sensing capabilities exceeded the minimum metrics, the system was not suitable for use in military applications. However, the prototyped network would work well in less demanding law enforcement environments. Additionally, the feasibility and the need to develop an integrated sensor-camera network were demonstrated.http://archive.org/details/testndevaluation109452780US Navy (USN) author.Approved for public release; distribution is unlimited
Radio Communications
In the last decades the restless evolution of information and communication technologies (ICT) brought to a deep transformation of our habits. The growth of the Internet and the advances in hardware and software implementations modified our way to communicate and to share information. In this book, an overview of the major issues faced today by researchers in the field of radio communications is given through 35 high quality chapters written by specialists working in universities and research centers all over the world. Various aspects will be deeply discussed: channel modeling, beamforming, multiple antennas, cooperative networks, opportunistic scheduling, advanced admission control, handover management, systems performance assessment, routing issues in mobility conditions, localization, web security. Advanced techniques for the radio resource management will be discussed both in single and multiple radio technologies; either in infrastructure, mesh or ad hoc networks
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