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Data Driven Selective Sensing for 3D Image AcquisitionCurtis, Phillip 26 November 2013 (has links)
It is well established that acquiring large amounts of range data with vision sensors can quickly lead to important data management challenges where processing capabilities become saturated and pre-empt full usage of the information available for autonomous systems to make educated decisions. While sub-sampling offers a naïve solution for reducing dataset dimension after acquisition, it does not capitalize on the knowledge available in already acquired data to selectively and dynamically drive the acquisition process over the most significant regions in a scene, the latter being generally characterized by variations in depth and surface shape in the context of 3D imaging.
This thesis discusses the development of two formal improvement measures, the first based upon surface meshes and Ordinary Kriging that focuses on improving scene accuracy, and the second based upon probabilistic occupancy grids that focuses on improving scene coverage. Furthermore, three selection processes to automatically choose which locations within the field of view of a range sensor to acquire next are proposed based upon the two formal improvement measures. The first two selection processes each use only one of the proposed improvement measures. The third selection process combines both improvement measures in order to counterbalance the parameters of the accuracy of knowledge about the scene and the coverage of the scene.
The proposed algorithms mainly target applications using random access range sensors, defined as sensors that can acquire depth measurements at a specified location within their field of view. Additionally, the algorithms are applicable to the case of estimating the improvement and point selection from within a single point of view, with the purpose of guiding the random access sensor to locations it can acquire. However, the framework is developed to be independent of the range sensing technology used, and is validated with range data of several scenes acquired from many different sensors employing various sensing technologies and configurations. Furthermore, the experimental results of the proposed selection processes are compared against those produced by a random sampling process, as well as a neural gas selective sensing algorithm.
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A design scheme of energy management, control, optimisation system for hybrid solar-wind and battery energy storages systemSarban Singh, Ranjit Singh January 2016 (has links)
Hybrid renewable energy system was introduced to improve the individual renewable energy power system’s productivity and operation-ability. This circumstance has led towards an extensive technological study and analysis on the hybrid renewable energy system. The extensive technological study is conducted using many different approaches, but in this research the linear programming, artificial intelligence and smart grid approaches are studied. This thesis proposed a complete hardware system development, implementation and construction of real-time DC Hybrid Renewable Energy System for solar-wind-battery energy source integrated with grid network support. The proposed real-time DC HRES hardware system adopts the hybrid renewable energy system concept which is composed of solar photovoltaic, wind energy system, battery energy storage system and grid network support. The real-time DC HRES hardware system research work is divided into three stages. Stage 1 involves modelling and simulation of the proposed system using MATLAB Simulink/Stateflow software. During this stage, system’s methodological design and development is emphasised. The obtained results are considered as fundamental finding to design, develop, integrate, implement and construct the real-time DC HRES hardware system. Stage II is designing and developing the electronic circuits for the real-time DC HRES hardware system using PROTEUS software. Real time simulation is performed on the electronic circuits to study and analyse the circuit’s behaviour. This stage also involves embedded software application development for the microcontroller PIC16F877A. Thus, continuous dynamic decision-making algorithm is developed and incorporated into microcontroller PIC16F877A. Next, electronic circuits and continuous dynamic decision-making algorithm are integrated with the microcontroller PIC16F877A as a real-time DC HRES hardware system to perform real time simulation. The real-time DC HRES hardware system simulation results are studied, analysed and compared with the results obtained in Stage 1. Any indifference between the obtained results in Stage 1 and Stage 2 are analysed and necessary changes are made. Stage 3 involves integrating, implementation and construction of real-time DC HRES. The continuous dynamic decision-making algorithm is also incorporated into the real microcontroller PCI16F877A development board. Real-time DC HRES’s experimental results have successfully demonstrated the system’s ability to perform supervision, coordination, management and control of all the available energy sources with lease dependency on the grid network. The obtained results demonstrated the energy management and optimisation of the available energy sources as primary power source deliver.
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Data Driven Selective Sensing for 3D Image AcquisitionCurtis, Phillip January 2013 (has links)
It is well established that acquiring large amounts of range data with vision sensors can quickly lead to important data management challenges where processing capabilities become saturated and pre-empt full usage of the information available for autonomous systems to make educated decisions. While sub-sampling offers a naïve solution for reducing dataset dimension after acquisition, it does not capitalize on the knowledge available in already acquired data to selectively and dynamically drive the acquisition process over the most significant regions in a scene, the latter being generally characterized by variations in depth and surface shape in the context of 3D imaging.
This thesis discusses the development of two formal improvement measures, the first based upon surface meshes and Ordinary Kriging that focuses on improving scene accuracy, and the second based upon probabilistic occupancy grids that focuses on improving scene coverage. Furthermore, three selection processes to automatically choose which locations within the field of view of a range sensor to acquire next are proposed based upon the two formal improvement measures. The first two selection processes each use only one of the proposed improvement measures. The third selection process combines both improvement measures in order to counterbalance the parameters of the accuracy of knowledge about the scene and the coverage of the scene.
The proposed algorithms mainly target applications using random access range sensors, defined as sensors that can acquire depth measurements at a specified location within their field of view. Additionally, the algorithms are applicable to the case of estimating the improvement and point selection from within a single point of view, with the purpose of guiding the random access sensor to locations it can acquire. However, the framework is developed to be independent of the range sensing technology used, and is validated with range data of several scenes acquired from many different sensors employing various sensing technologies and configurations. Furthermore, the experimental results of the proposed selection processes are compared against those produced by a random sampling process, as well as a neural gas selective sensing algorithm.
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Intelligent Sensing and Energy Efficient Neuromorphic Computing using Magneto-Resistive DevicesChamika M Liyanagedera (11191896) 27 July 2021 (has links)
<p>With the Moore’s Law era coming to an end, much attention has
been given to novel nanoelectronic devices as a key driving force behind
technological innovation. Utilizing the inherent device physics of
nanoelectronic components, for sensory and computational tasks have proven to
be useful in reducing the area and energy requirements of the underlying
hardware fabrics. In this work we demonstrate how the intrinsic noise present
in nano magnetic devices can pave the pathway for energy efficient neuromorphic
hardware. Furthermore, we illustrate how the unique magnetic properties of such
devices can be leveraged for accurate estimation of environmental magnetic
fields. We focus on spintronic technologies in particular, due to the low current
and energy requirements in contrast to traditional CMOS technologies.</p><p>Image
segmentation is a crucial pre-processing stage used in many object
identification tasks that involves simplifying the representation of an image
so it can be conveniently analyzed in the later stages of a problem. This is
achieved through partitioning a complicated image into specific groups based on
color, intensity or texture of the pixels of that image. Locally Excitatory
Globally Inhibitory Oscillator Network or LEGION is one such segmentation
algorithm, where synchronization and desynchronization between coupled
oscillators are used for segmenting an image. In this
work we present an energy efficient and scalable hardware implementation of LEGION
using stochastic Magnetic Tunnel Junctions that leverage the fast parallel</p><p>
nature
of the algorithm. We demonstrate that the proposed hardware is capable of segmenting
binary and gray-scale images with multiple objects more efficiently than<br>
existing
hardware implementations. </p><p>It is understood that the underlying device physics
of spin devices can be used for emulating the functionality of a spiking
neuron. Stochastic spiking neural networks based on nanoelectronic spin devices
can be a possible pathway of achieving brain-like compact and energy-efficient
cognitive intelligence. Current computational models attempt to exploit the
intrinsic device stochasticity of nanoelectronic synaptic or neural components
to perform learning and inference. However, there has been limited analysis on
the scaling effect of stochastic spin devices and its impact on the operation
of such stochastic networks at the system level. Our work attempts to explore
the design space and analyze the performance of nanomagnet based stochastic neuromorphic
computing architectures, for magnets with different barrier heights. We illustrate
how the underlying network architecture must be modified to account for the
random telegraphic switching behavior displayed by magnets as they are scaled into
the superparamagnetic regime.<br></p><p>Next we investigate how the magnetic properties
of spin devices can be utilized for real world sensory applications. Magnetic
Tunnel Junctions can efficiently translate variations in external magnetic
fields into variations in electrical resistance. We couple this property of
Magnetic Tunnel Junctions with Amperes law to design a non-invasive sensor to
measure the current flowing through a wire. We demonstrate how undesirable
effects of thermal noise and process variations can be suppressed through novel
analog and digital signal conditioning techniques to obtain reliable and
accurate current measurements. Our results substantiate that the proposed
noninvasive current sensor surpass other state-of-the-art technologies in terms
of noise and accuracy.<br></p><br>
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