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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Model bezdrátové senzorové sítě realizovaný v nástroji J-Sim / Wireless Sensor Network Simulation Model in J-Sim Tool

Vrzal, Tomáš January 2010 (has links)
This thesis deals with the issue of wireless sensor networks and communication protocols. Is explained of what the network is composed, what standards are used and in what sectors are most often used. The main scope of work is to introduce with the localization algorithms using in WSN. Algorithms are clearly divided into groups according to the methods used. In work is describes the structure used simulation tools J-Sim, for creating a wireless sensor network. To create network will be then applied different localization algorithms, which must first be implemented in a simulator using Java code. All generated classes and the algorithms are detailed described in the work. Results from simulations are detailed and graphically displays for individual localization algorithms.
172

Zabezpečení perimetru v extrémních podmínkách s využitím senzorových sítí / Protecting the perimeter in extreme conditions, using sensot networks

David, Jakub January 2013 (has links)
This master thesis deals with the theoretical analysis of wireless sensor networks, a description of selected types of sensors, listing their features and principle of operation for intrusion detection perimeter. Then there is described design and implementation of a wireless sensor node for intrusion detection perimeter usable in wireless sensor networks.
173

Monitorování stavu bezdrátových senzorových sítích agenty / Agent-Based Monitoring of Wireless Sensor Networks

Houšť, Marek January 2011 (has links)
The reader is first introduced with history and possible applications for wireless sensor networks. The thesis then describes the problems of wireless sensor networks and implementation tools for wireless sensor networks. The thesis also presents the system WSageNt and its client web interface. Practical part is based on the design of agent elements. Describes gradual implementation, testing and practical realization of these agent elements in the system WSageNt. The final part discusses the advantages and disadvantages of the project and identifies possible future expansion of the system.
174

Inteligentní agenti v bezdrátových sítích / Intelligent Agents in Wireless Networks

Kružliak, Miroslav January 2010 (has links)
This Master thesis deals with synchronization of sensor nodes in wireless sensor net. It is used event ordering by the implementation of logical clocks . Lamport's algorithm is used here for synchronization, which is trying to order events within the given system. The thesis also evaluates how appropriate this principle for synchronization is. The implementation has been carried out in agent-oriented language AgentSpeak on the Jason platform. Samson environment has been used and modified for observation of this synchronization's behaviour and testing purposes.
175

High Level Modeling and Planning ofWireless Sensor Network : Preliminary Study towards the Service Oriented Architecture

Dai, Bowei January 2012 (has links)
Nowadays, wireless sensor network (WSN) is becoming popular in various fields of different industries along with the rapid development of hardware and software. Whereas more and more WSN applications come into use has make it difficult for consumers especially those who do not have professional knowledge to use. So it is urgently necessary and significant to offer services which do not need professional knowledge to satisfy consumers’ requirements from the users’ point of view. Therefore, service oriented architecture (SOA) is introduced as a method to do our research from the users’ point of view. After asimple overall introduction of WSN which include the system architecture, hardware, software and supported technologies, we pay our emphasis on the power consumption modeling for WSN and get some formulations following the operation cycle. Last but not least, SOA method is analyzed and some SOA based WSN applications are introduced as examples to further understand of SOA based WSN for readers.
176

Residual Energy-Based Cluster-Head Selection in WSNs for IoT Application

Behera, Trupti Mayee, Mohapatra, Sushanta Kumar, Samal, Umesh Chandra, Khan, Mohammad S., Daneshmand, Mahmoud, Gandomi, Amir H. 01 June 2019 (has links)
Wireless sensor networks (WSNs) groups specialized transducers that provide sensing services to Internet of Things (IoT) devices with limited energy and storage resources. Since replacement or recharging of batteries in sensor nodes is almost impossible, power consumption becomes one of the crucial design issues in WSN. Clustering algorithm plays an important role in power conservation for the energy constrained network. Choosing a cluster head (CH) can appropriately balance the load in the network thereby reducing energy consumption and enhancing lifetime. This paper focuses on an efficient CH election scheme that rotates the CH position among the nodes with higher energy level as compared to other. The algorithm considers initial energy, residual energy, and an optimum value of CHs to elect the next group of CHs for the network that suits for IoT applications, such as environmental monitoring, smart cities, and systems. Simulation analysis shows the modified version performs better than the low energy adaptive clustering hierarchy protocol by enhancing the throughput by 60%, lifetime by 66%, and residual energy by 64%.
177

A Wide Input Power Line Energy Harvesting Circuit For Wireless Sensor Nodes

Wang, Jinhua January 2021 (has links)
Massive deployment of wireless IoT (Internet of Things) devices makes replacement or recharge of batteries expensive and impractical for some applications. Energy harvesting is a promising solution, and various designs are proposed to harvest power from ambient resources including thermal, vibrational, solar, wind, and RF sources. Among these ambient resources, AC powerlines are a stable energy source in an urban environment. Many researchers investigated methods to exploit this stable source of energy to power wireless IoT devices. The proposed circuit aims to harvest energy from AC powerlines with a wide input range of from 10 to 50 A. The proposed system includes a wake-up circuit and is capable of cold-start. A buck-boost converter operating in DCM is adopted for impedance matching, where the impedance is rather independent of the operation conditions. So, the proposed system can be applied to various types of wireless sensor nodes with different internal impedances. Experimental results show that the proposed system achieves an efficiency of 80.99% under the powerline current of 50 A. / M.S. / Nowadays, with the magnificent growth of IoT devices, a reliable, and efficient energy supply system becomes more and more important, because, for some applications, battery replacement is very expensive and sometimes even impossible. At this time, a well-designed self-contained energy harvesting system is a good solution. The energy harvesting system can extend the service life of the IoT devices and reduce the frequency of charging or checking the device. In this work, the proposed circuit aims to harvest energy from the AC power lines, and the harvested power intends to power wireless sensor nodes (WSNs). By utilizing the efficient and self-contained EH system, WSNs can be used to monitor the temperature, pressure, noise level and humidity etc. The proposed energy harvesting circuit was implemented with discrete components on a printed circuit board (PCB). Under a power line current of 50 A @ 50 Hz, the proposed energy harvesting circuit can harvest 156.6 mW, with a peak efficiency of 80.99 %.
178

Implementation and Evaluation of a TDMA Based Protocol for Wireless Sensor Networks

Fiske, Robert M. January 2010 (has links)
No description available.
179

Reliability of Data Collection and Transmission in Wireless Sensor Networks

Basheer, Al-Qassab 30 August 2013 (has links)
No description available.
180

Embedded Wireless Sensor Network for Aircraft/Automobile Tire Structural Health Monitoring

Gondal, Farrukh Mehmood 17 August 2007 (has links)
Structural Health Monitoring (SHM) of automobile tires has been an active area of research in the last few years. Within this area, the monitoring of strain on tires using wireless devices and networks is gaining prominence because these techniques do not require any wired connections. Various tire manufacturers are looking into SHM of automobile tires due to the Transportation Recall Enhancement, Accountability and Documentation (TREAD) act which demands installation of tire pressure monitoring devices within the tire. Besides measuring tire pressures, tire manufactures are also examining ways to measure strain and temperature as well to enhance overall safety of an automobile. A sensor system that can measure the overall strain of a tire is known as a centralized strain sensing system. However, a centralized strain sensing system cannot find the location and severity of the damage on the tire, which is a basic requirement. Various sensors such as acceleration and optical sensors have also been proposed to be used together to get more local damage information on the tire. In this thesis we have developed a strain sensing system that performs local strain measurements on the tire and transmits them to a console inside the vehicle wirelessly. Our sensing system utilizes a new sensing material called Metal RubberTM which is shown to be conductive like metal, and flexible as rubber. Also, we have also developed a reliable and an energy efficient geographic routing protocol for transporting strain data wirelessly from a tire surface to the driver of the automobile. / Master of Science

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