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Game theoretic methods for networked sensors and dynamic spectrum accessMaskery, Michael 05 1900 (has links)
Automated devices enabled by wireless communications are deployed for a variety of purposes.
As they become more ubiquitous, their interaction becomes increasingly important
for coexistence when sharing a scarce resource, and for leveraging potential cooperation to achieve larger design goals.
This thesis investigates the use of game theory as a tool for design and analysis of networked systems of automated devices
in the areas of naval defence, wireless environmental monitoring through sensor networks, and cognitive radio wireless communications.
In the first part, decentralized operation of naval platforms deploying
electronic countermeasures against missile threats is studied.
The problem is formulated as a stochastic game in which platforms independently plan and execute
dynamic strategies to defeat threats in two situations: where coordination is impossible due to lack of
communications, and where platforms hold different objectives but can coordinate, according
to the military doctrine of Network Enabled Operations.
The result is a flexible, robust model for missile deflection for advanced naval groups.
Next, the problem of cooperative environmental monitoring and communication in energy-constrained wireless sensor networks
is considered from a game-theoretic perspective. This leads to novel protocols in which sensors cooperatively trade off
performance with energy consumption with low communication and complexity overhead.
Two key results are an on-line adaptive learning algorithm for tracking the correlated equilibrium set of a slowly
varying sensor deployment game, and an analysis of the equilibrium properties of threshold policies in a
game with noisy, correlated measurements.
Finally, the problem of dynamic spectrum access for systems of cognitive radios is considered. A game theoretic formulation
leads to a scheme for competitive bandwidth allocation which respects radios' individual interests while enforcing fairness
between users. An on-line adaptive learning scheme is again proposed for negotiating fair, equilibrium resource allocations, while
dynamically adjusting to changing conditions.
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Glucose monitoring measuring blood glucose using vertical cavity surface emitting lasers (VCSELs)Talebi Fard, Sahba 11 1900 (has links)
Diabetes Mellitus is a common chronic disease that is an ever-increasing public health issue. Continuous glucose monitoring has been shown to help diabetes mellitus patients stabilize their glucose levels, leading to improved patient health. Hence, a glucose sensor, capable of continuous real-time monitoring, has been a topic of research for three decades. Current methods of glucose monitoring, however, require taking blood samples several times a day, hence patient compliance is an issue. Optical methods are one of the painless and promising methods that can be used for blood glucose predictions. However, having accuracies lower than what is acceptable clinically has been a major concern. To improve on the accuracy of the predictions, the signal-to-noise ratio in the spectrum can be increased, for which the use of thermally tunable vertical cavity surface emitting lasers (VCSELs) as the light source to obtain blood absorption spectra, along with a multivariate technique (Partial Least Square (PLS) techniques) for analysis, is proposed.
VCSELs are semiconductor lasers with small dimensions and low power consumption, which makes them suitable for implants. VCSELs provide higher signal-to-noise ratio as they have high power spectral density and operate within a small spectrum. In the current research, experiments were run for the preliminary investigations to demonstrate the feasibility of the proposed technique for glucose monitoring.
This research involves preliminary investigations for developing a novel optical system for accurate measurement of glucose concentration. Experiments in aqueous glucose solutions were designed to demonstrate the feasibility of the proposed technique for glucose monitoring. In addition, multivariate techniques, such as PLS, were customized for various specific purposes of this project and its preliminary investigation. This research will lead to the development of a small, low power, implantable optical sensor for diabetes patients, which will be a major breakthrough in the area of treating diabetes patients, upon successful completion of this research and development of the device.
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Remote environmental sensor array systemHall, Geoffrey G. 20 December 2007 (has links)
This thesis examines the creation of an environmental monitoring system for inhospitable environments. It has been named The Remote Environmental Sensor Array System or RESA System for short. This thesis covers the development of RESA from its inception, to the design and modeling of the hardware and software required to make it functional. Finally, the actual manufacture, and laboratory testing of the finished RESA product is discussed and documented.
The RESA System is designed as a cost-effective way to bring sensors and video systems to the underwater environment. It contains as water quality probe with sensors such as dissolved oxygen, pH, temperature, specific conductivity, oxidation-reduction potential and chlorophyll a. In addition, an omni-directional hydrophone is included to detect underwater acoustic signals. It has a colour, high-definition and a low-light, black and white camera system, which it turn are coupled to a laser scaling system. Both high-intensity discharge and halogen lighting system are included to illuminate the video images. The video and laser scaling systems are manoeuvred using pan and tilt units controlled from an underwater computer box. Finally, a sediment profile imager is included to enable profile images of sediment layers to be acquired. A control and manipulation system to control the instruments and move the data across networks is integrated into the underwater system while a power distribution node provides the correct voltages to power the instruments.
Laboratory testing was completed to ensure that the different instruments associated with the RESA performed as designed. This included physical testing of the motorized instruments, calibration of the instruments, benchmark performance testing and system failure exercises. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2007-12-19 10:49:51.335
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Device Deployment Strategies for Large-scale Wireless Sensor NetworksXu, Kenan 16 January 2008 (has links)
Planning device deployment is a fundamental issue in implementing wireless sensor network (WSN) applications. This design practice determines types, numbers and locations of devices in order to build a powerful and effective system using devices of limited energy supply and constrained capacities. The deployment plan decides the limits of many intrinsic properties of a WSN, such as coverage, connectivity, cost, and lifetime. In this thesis, we address the device deployment planning issues related to large-scale WSN systems.
We consider a typical deployment planning scenario in a heterogeneous two-tier WSN composed of sensor nodes and relay nodes. Sensor nodes form the lower tier of the network and are responsible for providing satisfactory sensing coverage to the application. Relay nodes form the upper tier of the network and they are responsible for forwarding data from sensor nodes to the base station. As so, relay nodes should provide reliable connectivity to sensor nodes for an extended period of time. We therefore address the sensor node deployment in terms of the sensing coverage and relay node deployment in terms of the communication connectivity and system lifetime.
For sensor node deployment, we propose a coverage-guaranteed sensor node deployment design technique. Using this technique, the sensing coverage is complete even if sensor nodes are randomly dispersed within a bounded range from its target locations according to a given grid pattern. In order to curb the increased cost due to extra sensor nodes that are used in the coverage-guaranteed deployment, while still maintaining a high-quality sensing coverage, we further study the probabilistic properties of the grid-based sensor node deployment in the presence of deployment errors.
For relay node deployment, we propose to extend the system lifetime by distributing relay nodes according to a density function, which is optimized in response to the energy consumption rate, so that the energy is dissipated at an approximately same rate across the network. We further craft the deployment density function to reconcile the needs of balanced energy consumption and strong sensor node connectivity.
The techniques proposed in this thesis fill the blank of available literature and can serve as guidelines for WSN designers, solution providers and system integrators of WSN applications. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2008-01-15 09:33:53.917
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DESIGN AND IMPLEMENTATION OF A COGNITIVE WIRELESS SENSOR NETWORK: APPLICATION TO ENVIRONMENT MONITORINGAALAMIFAR, FERESHTEH 28 September 2011 (has links)
Wireless sensor networks have applications in many places from wildlife environments to urban areas. Implementation of such a network is a challenging task because each specific application may require different constraints and objectives. To better meet the application requirements, cognitive wireless sensor network has been recently introduced. However, almost all the previous work in this area has been in theory or by simulation. Hence there is a demand to provide implementable ideas of cognition, implement, and analyze the results. The goal of this thesis is to implement a cognitive wireless sensor network with application in environment monitoring which is aware of the surrounding environment, updates its information based on the dynamic changes in the network status, makes appropriate decisions based on the gained awareness, and forwards required actions to involving nodes. An implementable cognitive idea is proposed based on the characteristics and goals of a cognitive system. Since transmission is one of the most power consuming processes in sensor nodes and non-efficient transmissions of data can lead to a shorter lifetime, this work tries to schedule nodes' transmission rate by the means of cognition and benefits from efficient scheduling of the redundant nodes to improve lifetime. To enhance a wireless sensor network with cognition, new nodes should be added to the architecture called cognitive nodes. Cognitive nodes will take care of most of the tasks in the cognition process while still there is a need to add a level of cognition to each individual node. The main contribution of this work is that it provides an implementable approach to cognition in wireless sensor networks, proposes a low complexity and low cost implementable idea for cognition, addresses implementation issues, and provides experimental results of different setups of the cognitive wireless sensor network. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-09-27 00:38:12.455
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Efficient Over-the-air Remote Reprogramming of Wireless Sensor NetworksSHAFI, NASIF BIN 29 November 2011 (has links)
Over-the-air reprogramming is an important aspect of managing large wireless sensor networks. However, reprogramming deployed sensor networks poses significant challenges due to the energy, processing power and memory limitation of sensor nodes. For improved energy efficiency, a reprogramming mechanism should use less transmission and flash writing overhead. Past research has proposed different mechanisms for reprogramming deployed sensor networks. However, all of these mechanisms produce large patches if software modifications involve changing program layouts and shifting global variables. In addition, existing mechanisms use large amounts of external flash and rewrite entire internal flash. In this thesis, we present a differential reprogramming mechanism called QDiff that mitigates the effects of program layout modifications and retains maximum similarity between old and new software using a clone detection mechanism. Moreover, QDiff organizes the global variables in a novel way that eliminates the effect of variable shifting. Our experiments show that QDiff requires near-zero external flash, and significantly lower internal flash rewriting and transmission overhead than leading existing differential reprogramming mechanisms. / Thesis (Master, Computing) -- Queen's University, 2011-11-29 14:11:44.138
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A Study of Six-Axis MEMS Sensors for Load Detection in Biomedical ApplicationsBenfield, David C. Unknown Date
No description available.
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Electromechanical Behaviour of Surface-Bonded Piezoelectric Sensors/Actuators with Imperfect Adhesive LayersJin, Congrui Unknown Date
No description available.
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Lanthanide Luminescent Metal-Organic Frameworks with Linear Dicarboxylate Ligands: Synthesis, Structure and SensingLi, Yu 10 January 2014 (has links)
The object of this thesis is to explore functionalized linear dicarboxylate ligands for constructing luminescent metal-organic framework (MOF) sensors. The first series of ligands developed is based on functionalized (E)-4,4'-(ethene-1,2-diyl)dibenzoic acids. Luminescent MOFs have been synthesized from these ligands and their porosity, thermal stability, luminescent properties have been discussed. The second series of ligands is based on functionalized [1,1':4',1''-terphenyl]-4,4''-dicarboxylic acid. Ligands bearing methyl, methoxyl, thioether, aldehyde, ketone, quaternary ammonium side chains have been synthesized and constructed into luminescent MOFs. Their structures, thermal stability, luminescent properties, solvent-dependent luminescence and the underlying mechanisms have been discussed. Vapor sensing experiments have been conducted with MOFs bearing ether and thioether side chains and strong luminescence turn-on is triggered by certain solvents. The MOF with ether side chains has been further tested as sensor slides to evaluate its response rate and recyclability.
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Lanthanide Luminescent Metal-Organic Frameworks with Linear Dicarboxylate Ligands: Synthesis, Structure and SensingLi, Yu 10 January 2014 (has links)
The object of this thesis is to explore functionalized linear dicarboxylate ligands for constructing luminescent metal-organic framework (MOF) sensors. The first series of ligands developed is based on functionalized (E)-4,4'-(ethene-1,2-diyl)dibenzoic acids. Luminescent MOFs have been synthesized from these ligands and their porosity, thermal stability, luminescent properties have been discussed. The second series of ligands is based on functionalized [1,1':4',1''-terphenyl]-4,4''-dicarboxylic acid. Ligands bearing methyl, methoxyl, thioether, aldehyde, ketone, quaternary ammonium side chains have been synthesized and constructed into luminescent MOFs. Their structures, thermal stability, luminescent properties, solvent-dependent luminescence and the underlying mechanisms have been discussed. Vapor sensing experiments have been conducted with MOFs bearing ether and thioether side chains and strong luminescence turn-on is triggered by certain solvents. The MOF with ether side chains has been further tested as sensor slides to evaluate its response rate and recyclability.
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