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Localized Pipeline Encroachment Detector System Using Sensor NetworkOu, Xiaoxi 1986- 16 December 2013 (has links)
Detection of encroachment on pipeline right-of-way is important for pipeline safety. An effective system can provide on-time warning while reducing the probability of false alarms. There are a number of industry and academic developments to tackle this problem. This thesis is the first to study the use of a wireless sensor network for pipeline right-of-way encroachment detection. In the proposed method, each sensor node in the network is responsible for detecting and transmitting vibration signals caused by encroachment activities to a base station (computer center). The base station monitors and analyzes the signals. If an encroachment activity is detected, the base station will send a warning signal. We describe such a platform with hardware configuration and software controls, and the results demonstrate that the platform is able to report our preliminary experiments in detecting digging activities by a tiller in the natural and automotive noise.
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Coverage-awareness Scheduling Protocols for Wireless Sensor NetworksFei, Xin January 2012 (has links)
The coverage and energy issues are the fundamental problems which prevent the development of wireless sensor networks. In order to accurately evaluate the monitoring quality (coverage), one needs to model the interactive of sensors, phenomenons and the environment. Furthermore, in collaborative with scheduling algorithm and computer optimization, protocols can improve the overall monitoring quality and prolong the lifetime of network. This thesis is an investigation of coverage problem and its relative applications in the wireless sensor networks. We first discuss the realistic of current boolean sensing model and propose an irregular sensing model used to determine the coverage in the area with obstacles. We then investigate a joint problem of maintaining the monitoring quality and extending the lifetime of network by using scheduling schemes. Since the scheduling problem is NP hard, genetic algorithm and Markov decision process are used to determine an achievable optimal result for the joint problem of coverage-preserving and lifetime-prolong. In order to avoid the cost of centralized or distributed scheduling algorithms, a localized coverage-preserving scheduling algorithm is proposed by exploring the construction process of Voronoi diagram. Besides exploring the coverage characteristic in a static wireless sensor network, we investigate the coverage problem when the mobile elements are introduced into network. We consider the single-hop mobile data gathering problem with the energy efficiency and data freshness concerns in a wireless sensor network where the connectivity cannot be maintained. We first investigate the upper/lower bound of the covering time for a single collector to cover the monitoring area. Through our investigation we show that for a bounded rectangle area a hexagon walk could explore the area more efficiently than a random walk when the edges of area are known. We then propose a virtual force mobile model (VFM) in which the energy consumption for data transmission is modeled as a virtual elastic force and used to guide of mobile collectors to move to optimal positions for energy saving.
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Determination of Cycle Time Constraints in Case of Link Failure in Closed Loop Control in Internet of ThingsAinchwar, Arpit January 2017 (has links)
In today’s era of the Internet of Things, it is crucial to study the real-time dependencies of the web, its failures and time delays. Today, smart grids, sensible homes, wise water networks, intelligent transportation, infrastructure systems that connect our world over are developing fast. The shared vision of such systems is typically associated with one single conception Internet of Things (IoT), where through the deployment of sensors, the entire physical infrastructure is firmly fastened with information and communication technologies; where intelligent observation and management is achieved via the usage of networked embedded devices.
The performance of a real-time control depends not only on the reliability of the hardware and software used but also on the time delay in estimating the output, because of the effects of computing time delay on the control system performance. For a given fixed sampling interval, the delay and loss issues are the consequences of computing time delay. The delay problem occurs when the computing time delay is non-zero but smaller than the sampling interval, while the loss problem occurs when the computing time delay is greater than, or equal to, the sampling interval, i.e., loss of the control output. These two queries are analyzed as a means of evaluating real-time control systems. First, a general analysis of the effects of computing time delay is presented along with necessary conditions for system stability. In this thesis, we will focus on the experimental study of the closed loop control system in the internet of things to determine the cycle time constraints in case of link failure.
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Mission-driven Sensor Network Design for Space Domain AwarenessHarris, Cameron Douglas 09 December 2024 (has links)
This research presents a novel framework for optimizing sensor networks to enhance Space Domain Awareness in the face of a burgeoning resident space object population. By employing advanced metaheuristic optimization techniques and high-fidelity modeling and simulation, this research investigates the intricate interplay between sensor characteristics, network topology, and state estimation performance. The research aims to develop actionable recommendations for optimizing sensor network design, considering factors such as viewing geometry, sensor phenomenology, and background noise. Through rigorous simulations and analysis, this work seeks to contribute significantly to the advancement of Space Domain Awareness. A key product of this research is the development of a novel lattice-based genetic algorithm tailored for constrained metaheuristic optimization that converges in 15% fewer generations than traditional methods. This algorithm demonstrates its effectiveness in producing practical sensor network designs that can enhance space object tracking and surveillance capabilities. Results will show network designs that fill current coverage gaps over the Atlantic and Pacific oceans, remain consistent with geographical and geopolitical boundaries, and exploit regions with favorable environmental conditions. The outcome is a set of actionable solutions that triple observation capacity and reduce catalog observation gap times by up to 50%. / Doctor of Philosophy / Space Domain Awareness is critical for ensuring the safety and security of space operations.
As the number of objects in space continues to grow, strategic sensor network design is essential for effective tracking and surveillance. This research presents a novel approach to designing sensor networks that maximizes their effectiveness towards specified mission outcomes. Leveraging advanced computer modeling and optimization techniques, a method is developed that considers factors like sensor location, capabilities, and the environment. The research has led to improved sensor network designs, enhanced coverage of space, and reduced gaps in observations of space objects. Overall, this research provides valuable insights and practical solutions for improving SDA capabilities. These results can help ensure the safety and security of space operations for the future space environment.
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A group-based architecture and protocol for wireless sensor networksGarcía Pineda, Miguel 12 March 2013 (has links)
There are many works related to wireless sensor networks (WSNs) where
authors present new protocols with better or enhanced features, others just
compare their performance or present an application, but this work tries to provide
a different perspective. Why don¿t we see the network as a whole and split it into
groups to give better network performance regardless of the routing protocol?
For this reason, in this thesis we demonstrate through simulations that
node¿s grouping feature in WSN improves the network¿s behavior. We propose the
creation of a group-based architecture, where nodes have the same functionality
within the network. Each group has a head node, which defines the area in which
the nodes of such group are located. Each node has a unique node identifier
(nodeID). First group¿s node makes a group identifier (groupID).
New nodes will know their groupID and nodeID of their neighbors. End
nodes are, physically, the nodes that define a group. When there is an event on a
node, this event is sent to all nodes in its group in order to take an appropriate
action. End nodes have connections to other end nodes of neighboring groups and
they will be used to send data to other groups or to receive information from other
groups and to distribute it within their group. Links between end nodes of different
groups are established mainly depending on their position, but if there are multiple
possibilities, neighbor nodes could be selected based on their ability ¿, being ¿ a
choice parameter taking into account several network and nodes parameters. In
order to set group¿s boundaries, we can consider two options, namely: i) limiting
the group¿s diameter of a maximum number of hops, and ii) establishing
boundaries of covered area.
In order to improve the proposed group-based architecture, we add
collaboration between groups. A collaborative group-based network gives better
performance to the group and to the whole system, thereby avoiding unnecessary
message forwarding and additional overheads while saving energy. Grouping
nodes also diminishes the average network delay while allowing scaling the
network considerably. In order to offer an optimized monitoring process, and in
order to offer the best reply in particular environments, group-based collaborative
systems are needed. They will simplify the monitoring needs while offering direct
control.
Finally, we propose a marine application where a variant of this groupbased architecture could be applied and deployed. / García Pineda, M. (2013). A group-based architecture and protocol for wireless sensor networks [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/27599 / Premios Extraordinarios de tesis doctorales
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Using genetic algorithms to optimise wireless sensor network designFan, Jin January 2009 (has links)
Wireless Sensor Networks(WSNs) have gained a lot of attention because of their potential to immerse deeper into people' lives. The applications of WSNs range from small home environment networks to large habitat monitoring. These highly diverse scenarios impose different requirements on WSNs and lead to distinct design and implementation decisions. This thesis presents an optimization framework for WSN design which selects a proper set of protocols and number of nodes before a practical network deployment. A Genetic Algorithm(GA)-based Sensor Network Design Tool(SNDT) is proposed in this work for wireless sensor network design in terms of performance, considering application-specific requirements, deployment constrains and energy characteristics. SNDT relies on offine simulation analysis to help resolve design decisions. A GA is used as the optimization tool of the proposed system and an appropriate fitness function is derived to incorporate many aspects of network performance. The configuration attributes optimized by SNDT comprise the communication protocol selection and the number of nodes deployed in a fixed area. Three specific cases : a periodic-measuring application, an event detection type of application and a tracking-based application are considered to demonstrate and assess how the proposed framework performs. Considering the initial requirements of each case, the solutions provided by SNDT were proven to be favourable in terms of energy consumption, end-to-end delay and loss. The user-defined application requirements were successfully achieved.
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Three-tier wireless sensor network infrastructure for environmental monitoringHan, Wei January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / Naiqian Zhang / A two-tier wireless data communication system was developed to remotely monitor sediment concentration in streams in real time. The system used wireless motes and other devices to form a wireless sensor network to acquire data from multiple sensors. The system also used a Stargate, a single-board computer, as a gateway to manage and control data flow and wireless data transfer. The sensor signals were transmitted from an AirCard on the Stargate to an Internet server through the General Packet Radio Service (GPRS) provided by a commercial GSM cellular carrier. Various types of antennas were used to boost the signal level in a radio-hostile environment. Both short- and long-distance wireless data communications were achieved. Power supplies for the motes, Stargate, and AirCard were improved for reliable and robust field applications. The application software was developed using Java, C, nesC, LabView, and SQL to ensure seamless data transfer and enable both on-site and remote monitoring. Remote field tests were carried out at different locations with different GPRS signal strengths and a variety of landscapes.
A three-tier wireless sensor network was then developed and deployed at three military installations around the country – Fort Riley in Kansas, Fort Benning in Georgia, and Aberdeen Proving Ground in Maryland - to remotely monitor sediment concentration and movement in real time. Sensor nodes, gateway stations, repeater stations, and central stations were strategically deployed to insure reliable signal transmissions. Radio signal strength was tested to analyze effects of distance, vegetation, and topographical barriers. Omni- and Yagi-directional antennas with different gains were tested to achieve robust, long-range communication in a wireless-hostile environment. Sampling times of sensor nodes within a local sensor network were synchronized at the gateway station. Error detection algorithms were developed to detect errors caused by interference and other impairments of the transmission path. GSM and CDMA cellular modems were used at different locations based on cellular coverage. Data were analyzed to verify the effectiveness and reliability of the three-tier WSN.
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Designing and analyzing an event service for sensor networksGujrati, Sumeet January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Gurdip Singh / This work is motivated by the OMG’s CORBA Event Service Specification. CORBA is the acronym for Common Object Request Broker Architecture. In this research, we implemented and analyzed an event service using a model similar to the OMG model for sensor networks applications which are written in nesC programming language, an extension of C programming language. This implementation has been tested on a test bed created using Crossbow’s TelosB motes and Crossbow’s Stargate Netbridge modules as gateways. Event service interface implementations, which reside on the motes, are written in nesC. The data routing part, which is done through Stargate Netbridges, is written in the C language. This document contains experimental results obtained by deploying and running the implementation on the test bed.
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GUI abstraction of a sensor field on mobile deviceChauhan, Gaurav January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Gurdip Singh / A sensor network can be used to observe events performed by physical entities and their physical
locations. The growing need of wireless sensor networks to monitor different events can be
accomplished by tiny computing platforms called Motes. Having a GUI abstraction of the region
can help in getting a heads up display of the region which can be used for several purposes, e.g.
in hospitals for tracking different events in case of a fire emergency. It can be helpful for
firefighters entering a large building by providing them prior information of a building layout as
it is difficult to see through due to heavy smoke. This project develops an approach to show via
GUI information of a region with the help of motes transferring data wirelessly. It is a 3-tier
application including a server, a mobile client and a mote setup. The motes execute TinyOS,
which is specifically designed operating system for sensor networks.
The project has been tested in the computer science department building, Crossbow’s TelosB
motes have been used for the mote setup. The programs for the motes are written in nesC (dialect
of C), and the client and the server program are written in Java.
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Federated Sensor Network architectural design for the Internet of Things (IoT)Xu, Ran January 2013 (has links)
An information technology that can combine the physical world and virtual world is desired. The Internet of Things (IoT) is a concept system that uses Radio Frequency Identification (RFID), WSN and barcode scanners to sense and to detect physical objects and events. This information is shared with people on the Internet. With the announcement of the Smarter Planet concept by IBM, the problem of how to share this data was raised. However, the original design of WSN aims to provide environment monitoring and control within a small scale local network. It cannot meet the demands of the IoT because there is a lack of multi-connection functionality with other WSNs and upper level applications. As various standards of WSNs provide information for different purposes, a hybrid system that gives a complete answer by combining all of them could be promising for future IoT applications. This thesis is on the subject of `Federated Sensor Network' design and architectural development for the Internet of Things. A Federated Sensor Network (FSN) is a system that integrates WSNs and the Internet. Currently, methods of integrating WSNs and the Internet can follow one of three main directions: a Front-End Proxy solution, a Gateway solution or a TCP/IP Overlay solution. Architectures based on the ideas from all three directions are presented in this thesis; this forms a comprehensive body of research on possible Federated Sensor Network architecture designs. In addition, a fully compatible technology for the sensor network application, namely the Sensor Model Language (SensorML), has been reviewed and embedded into our FSN systems. The IoT as a new concept is also comprehensively described and the major technical issues discussed. Finally, a case study of the IoT in logistic management for emergency response is given. Proposed FSN architectures based on the Gateway solution are demonstrated through hardware implementation and lab tests. A demonstration of the 6LoWPAN enabled federated sensor network based on the TCP/IP Overlay solution presents a good result for the iNET localization and tracking project. All the tests of the designs have verified feasibility and achieve the target of the IoT concept.
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