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Digital Beamforming Array Phase Calibration Techniques For Multi-Pass Interferometric Sar, Kelly Cheung
Digital Beamforming Array Phase Calibration Techniques For Multi-Pass Interferometric Sar, Kelly Cheung
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Calibration plays a critical role in the optimal performance of algorithms in digital beamforming arrays. Phase incoherency between elements results in poor beamforming with decreased gain and higher sidelobes, leading to a decrease in accuracy and sensitivity of measurements. A similar problem exists in performing multi-pass interferometric SAR (IFSAR) processing of SAR data stacks to generate topological maps of the scene, where phase errors translate to height errors. By treating each SAR image in the data stack like an element of a uniform linear array, this thesis explores several phase calibration techniques that can be used to calibrate digital beamforming …
Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal
Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal
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Since their invention in 1958, Integrated Circuits (ICs) have become increasingly more complex, sophisticated, and useful. As a result, they have worked their way into every aspect of our lives, for example: personal electronic devices, wearable electronics, biomedical sensors, autonomous driving cars, military and defense applications, and artificial intelligence, to name some areas of applications. These examples represent both collectively, and sometimes individually, multi-trillion-dollar markets. However, further development of ICs has been predicted to encounter a performance bottleneck as the mainstream silicon industry, approaches its physical limits. The state-of-the-art of today’s ICs technology will be soon below 3nm. At such …
Modeling, Simulation, And Hardware Testing Of A Noise-Canceller Adc Architecture, Ethan R. Rando
Modeling, Simulation, And Hardware Testing Of A Noise-Canceller Adc Architecture, Ethan R. Rando
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Analog-to-Digital Converters (ADCs) are essential elements of most complex electronic devices. ADCs allow for an analog signal to be converted into the digital domain, and thus interpreted by a digital circuit or model. While ADCs are extremely common, they are not immune from common tradeoffs when being designed and implemented. The most prominent tradeoff when selecting or designing an ADC is whether to pursue a high conversion rate or a high resolution on the digital output. There are some ADC designs that allow for relatively high resolution while maintaining a respectable conversion rate, however these designs often come at the …
Multi-Variable Phase And Gain Calibration For Multi-Channel Transmit Signals, Ryan C. Ball
Multi-Variable Phase And Gain Calibration For Multi-Channel Transmit Signals, Ryan C. Ball
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A method for software-defined radio array calibration is presented. The method implements a matched filter approach to calculate the phase shift between channels. The temporal stability of the system and calibration coefficients are shown through the standard deviation over the course of four weeks. The standard deviation of the phase correction was shown to be less than 2 deg. for most channels in the array and within 8 deg. for the most extreme case. The standard deviation in amplitude scaling was calculated to be less than 0.06 for all channels in the array. The performance of the calibration is evaluated …
Prediction Of Ka-Band Radar Cross Section With Thz Scale Models With Varying Surface Roughness, Andrew J. Huebner
Prediction Of Ka-Band Radar Cross Section With Thz Scale Models With Varying Surface Roughness, Andrew J. Huebner
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Radar cross section (RCS) of electrically large targets can be challenging and expensive to measure. The use of scale models to predict the RCS of such large targets saves time and reduces facility requirements. This study investigates Ka-band (27 to 29 GHz) RCS prediction from scale model measurements at 500 to 750 GHz. Firstly, the coherent quasi-monostatic turntable RCS measurement system is demonstrated. Secondly, three aluminum 18:1 scale dihedrals with surface roughness up to 218 icroinches are measured to investigate how the roughness affects the Ka-band prediction. The measurements are compared to a parametric scattering model for the specular response, …
Direct Ink Write Processing Of Signal Crossovers Using Aerosol Jet Printing Method, Lucas A. Clark
Direct Ink Write Processing Of Signal Crossovers Using Aerosol Jet Printing Method, Lucas A. Clark
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Electronics in different applications, such as in medical imaging devices, radar systems, communication transmitters, and optical drives, often require various power and signal lines to be integrated at board level. In such cases, different lines may cross over one another in three-dimensional space for efficient electronic integration. Crossovers are usually achieved by adding additional layers to a PCB. However, these additional layers increase the cost, weight, and complexity of the component. By creating a process and structure to offer board-level heterogenous integration, these factors may be reduced. RF-DC crossovers were designed and additively manufactured using an aerosol jet printer. Benzocyclobutene …
Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green
Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green
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Simultaneous Localization and Mapping (SLAM) is the process of using distance measurements to points in the surrounding environment to build a digital map and perform localization. It has been observed that featureless environments like tunnels or straight hallways will cause positioning faults in SLAM. This research investigates the fault diagnosis and accommodation problem for a laser-rangefinder-based SLAM systems on a quadrotor. A potential solution of using optical flow as velocity estimate and an extended Kalman filter (EKF) to perform position estimation is proposed. A fault diagnosis method for detecting faults in positional SLAM data or optical flow velocity data is …
Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris
Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris
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A method for the beam forming control of an array of reconfigurable antennas is presented. The method consists of using two parallel convolutional neural networks (CNNs) to analyze a desired radiation pattern image, or mask, and provide a suggestion for the reconfigurable element state, array shape, and steering weights necessary to obtain the radiation pattern. This research compares beam forming systems designed for three distinct element types: a patch antenna, a reconfigurable square spiral antenna restricted to a single reconfigurable state, and the fully reconfigurable square spiral. The parametric sweeps for the design of the CNNs are presented along with …
Unit Circle Roots Based Sensor Array Signal Processing, Jared P. Smith
Unit Circle Roots Based Sensor Array Signal Processing, Jared P. Smith
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As technology continues to rapidly evolve, the presence of sensor arrays and the algorithms processing the data they generate take an ever-increasing role in modern human life. From remote sensing to wireless communications, the importance of sensor signal processing cannot be understated. Capon's pioneering work on minimum variance distortionless response (MVDR) beamforming forms the basis of many modern sensor array signal processing (SASP) algorithms. In 2004, Steinhardt and Guerci proved that the roots of the polynomial corresponding to the optimal MVDR beamformer must lie on the unit circle, but this result was limited to only the MVDR. This dissertation contains …
Cmos Wide Tuning Gilbert Mixer With Controllable If Bandwidth In Upcoming Rf Front End For Multi-Band Multi-Standard Applications, Jianfeng Ren
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The current global system for mobile communications, wireless local area, Bluetooth, and ultra-wideband demands a multi-band/multi-standard RF front end that can access all the available bandwidth specifications. Trade-offs occur between power consumption, noise figure, and linearity in CMOS Gilbert mixer wide tuning designs. Besides, it is preferable to have a constant IF bandwidth for different gain settings as the bandwidth varies with the load impedance when an RF receiver is tuned to a higher frequency. My dissertation consists of three parts. First, a tunable constant IF bandwidth Gilbert mixer is introduced for multi-band standard wireless applications such as 802.11 a/b/g …
Quadrature Phase-Domain Adpll With Integrated On-Line Amplitude Locked Loop Calibration For 5g Multi-Band Applications, Xiaomeng Zhang
Quadrature Phase-Domain Adpll With Integrated On-Line Amplitude Locked Loop Calibration For 5g Multi-Band Applications, Xiaomeng Zhang
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5th generation wireless systems (5G) have expanded frequency band coverage with the low-band 5G and mid-band 5G frequencies spanning 600 MHz to 4 GHz spectrum. This dissertation focuses on a microelectronic implementation of CMOS 65 nm design of an All-Digital Phase Lock Loop (ADPLL), which is a critical component for advanced 5G wireless transceivers. The ADPLL is designed to operate in the frequency bands of 600MHz-930MHz, 2.4GHz-2.8GHz and 3.4GHz-4.2GHz. Unique ADPLL sub-components include: 1) Digital Phase Frequency Detector, 2) Digital Loop Filter, 3) Channel Bank Select Circuit, and 4) Digital Control Oscillator. Integrated with the ADPLL is a 90-degree active …
Amygdala Modeling With Context And Motivation Using Spiking Neural Networks For Robotics Applications, Matthew Aaron Zeglen
Amygdala Modeling With Context And Motivation Using Spiking Neural Networks For Robotics Applications, Matthew Aaron Zeglen
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Cognitive capabilities for robotic applications are furthered by developing an artificial amygdala that mimics biology. The amygdala portion of the brain is commonly understood to control mood and behavior based upon sensory inputs, motivation, and context. This research builds upon prior work in creating artificial intelligence for robotics which focused on mood-generated actions. However, recent amygdala research suggests a void in greater functionality. This work developed a computational model of an amygdala, integrated this model into a robot model, and developed a comprehensive integration of the robot for simulation, and live embodiment. The developed amygdala, instantiated in the Nengo Brain …
Low-Power, Low-Cost, & High-Performance Digital Designs : Multi-Bit Signed Multiplier Design Using 32nm Cmos Technology, N V Vijaya Krishna Boppana
Low-Power, Low-Cost, & High-Performance Digital Designs : Multi-Bit Signed Multiplier Design Using 32nm Cmos Technology, N V Vijaya Krishna Boppana
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Binary multipliers are ubiquitous in digital hardware. Digital multipliers along with the adders play a major role in computing, communicating, and controlling devices. Multipliers are used majorly in the areas of digital signal and image processing, central processing unit (CPU) of the computers, high-performance and parallel scientific computing, machine learning, physical layer design of the communication equipment, etc. The predominant presence and increasing demand for low-power, low-cost, and high-performance digital hardware led to this work of developing optimized multiplier designs. Two optimized designs are proposed in this work. One is an optimized 8 x 8 Booth multiplier architecture which is …
Demonstration Of High-Temperature Operation Of Beta-Gallium Oxide (Β-Ga2o3) Metal-Oxide-Semiconductor Field Effect Transistors (Mosfet) With Electrostatic Model In Comsol, Nicholas Paul Sepelak
Demonstration Of High-Temperature Operation Of Beta-Gallium Oxide (Β-Ga2o3) Metal-Oxide-Semiconductor Field Effect Transistors (Mosfet) With Electrostatic Model In Comsol, Nicholas Paul Sepelak
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β-Ga2O3 is a robust semiconductor material set with a large band gap of ~4.8 eV, low intrinsic carrier concentration, and high melting point that offers a stable platform for operating electronic devices at high temperatures and extreme environments. The first half of this thesis will cover the fabrication of a fixture and packaging to test electronic components at high temperatures. Then it will highlight the characterization of β-Ga2O3 field effect transistors from room temperature (RT) up to 500 °C. The devices, fabricated with Ni/Au and Al2O3 gate metal-oxide-semiconductor (MOS), demonstrate stable operation up to 500 oC. The tested device shows …
Fault-Tolerant Control Of Autonomous Ground Vehicle Under Actuator And Sensor, Vaishnavi Janakiraman
Fault-Tolerant Control Of Autonomous Ground Vehicle Under Actuator And Sensor, Vaishnavi Janakiraman
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Unmanned ground vehicles have a wide range of potential applications including autonomous driving, military surveillance, emergency responses, and agricultural robotics, etc. Since such autonomous vehicles need to operate reliably at all times, despite the possible occurrence of faulty behaviors in some system components, the development of fault-tolerant control schemes is a crucial step in ensuring reliable and safe operations. In this research, a fault-tolerant control scheme is developed for a nonlinear ground vehicle model with possible occurrence of both actuator faults in the form of loss of effectiveness (LOE) and sensor bias faults. Based on the vehicle and fault models …
Design And Implementation Of Fully Integrated Cmos On-Chip Bandpass Filter With Wideband High-Gain Low Noise Amplifier, Yu Wang
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Current trends of fully integrated CMOS on-chip bandpass filter are classified into 1) the component level (i.e., active inductor, Q-enhanced passive inductor, negative resistance cancellation), and 2) the circuit level (i.e., adding transmission zeros on stopband, applying the zigzag technique for fewer inductors, superposition of different resonators). The demand for monolithic designs for portable devices attracts market interest in a fully integrated CMOS on-chip bandpass filter. Optimized minimal inductors (OMI) bandpass filter is a good platform for use in both active and passive bandpass filters, mainly because 1) it provides good stopband rejection for high interface attenuation, and 2) the …
The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer
The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer
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A new method for analyzing the effectiveness of NMR impulse power amplifiers was developed using a classical linear systems approach to NMR. The method demonstrates a way to compare NMR power amplifiers and outputs. Thermodynamic calculations and the harmonic content of NMR amplifiers is presented to provide a complete description of the NMR power amplifier design problem. A design procedure for class E NMR power amplifiers with a pi-impedance matching network is outlined for matching the amplifier to the transmitter coil. The thesis concludes with the presentation of a 53 MHz power amplifier developed with the procedure. The complete amplifier …
Interferometry Analysis Method For Colliding Plasma Generated With Exploded Wires, Michael D. Gruesbeck
Interferometry Analysis Method For Colliding Plasma Generated With Exploded Wires, Michael D. Gruesbeck
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Building upon recent work to estimate electron and ion densities from paired interferograms, the current work develops a model for the 2D interference phase function. Unlike the previous work that only estimated a radial plasma profile from images of a singly exploded straight Cu wire, we estimate 2D properties from a colliding plasma generated from two simultaneously exploded wires. First, a 2D phase model is proposed for the interference patterns of the images taken at 1064 nm and 532 nm. Then, the model parameters are estimated using Fourier analysis. Secondly, the plasma region in each image is partitioned into subregions …
Hardware Security And Side Channel Power Analysis For 16x16 Booth Multiplier In 65nm Cmos Technology, Kanchan Vissamsetty
Hardware Security And Side Channel Power Analysis For 16x16 Booth Multiplier In 65nm Cmos Technology, Kanchan Vissamsetty
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As feature size is scaling down, dynamic power consumption reduces but static power consumption increases. Due to the increase of static power, leakage currents as a source, the information can be exploited successfully as a side-channel to recover the secrets of the cryptographic implementations. An attacker who has access to the hardware fabrication can insert a Trojan to the design to steal or alter information. In this thesis, a post-fab static voltage variation/detection technique is developed to detect the potential fabrication process Trojan insertion. The technique is, dividing the designed circuit into N equal segments, where each segment would have …
Deep Learning For Compressive Sar Imaging With Train-Test Discrepancy, Morgan R. Mccamey
Deep Learning For Compressive Sar Imaging With Train-Test Discrepancy, Morgan R. Mccamey
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We consider the problem of compressive synthetic aperture radar (SAR) imaging with the goal of reconstructing SAR imagery in the presence of under sampled phase history. While this problem is typically considered in compressive sensing (CS) literature, we consider a variety of deep learning approaches where a deep neural network (DNN) is trained to form SAR imagery from limited data. At the cost of computationally intensive offline training, on-line test-time DNN-SAR has demonstrated orders of magnitude faster reconstruction than standard CS algorithms. A limitation of the DNN approach is that any change to the operating conditions necessitates a costly retraining …
Reconfigurable Antenna Array Using The Pin-Diode-Switched Printed Square Spiral Element, Corey M. Stamper
Reconfigurable Antenna Array Using The Pin-Diode-Switched Printed Square Spiral Element, Corey M. Stamper
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A dual-band array of reconfigurable elements is modeled and simulated. The array consists of four single square spiral microstrip antennas that are corporately fed and are used as a unit cell. The single square spiral uses two PIN diodes as switching elements to achieve reconfiguration. The array has four switch states that can operate over four discrete frequencies in the S and C bands. The unit cell radiation pattern is used with the pattern multiplication model to quickly simulate the array pattern of larger arrays. A 3 x 3 array of the unit cells is modeled with only the center …
The Effect Of Winding Curvature And Core Permeability On The Power Losses And Leakage Inductance Of High-Frequency Transformers, Daniel J. Whitman
The Effect Of Winding Curvature And Core Permeability On The Power Losses And Leakage Inductance Of High-Frequency Transformers, Daniel J. Whitman
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At the frequencies used in switching dc-dc converters, the skin and proximity effects have a significant effect on both the losses and leakage inductance of the transformers used in these circuits. Analytical expressions that have been derived to calculate ac resistance and leakage inductance have primarily used a 1-D approximation. They also have used Cartesian coordinates or approximations that are equivalent to Cartesian coordinates, as well as usually assuming an ideal core of infinite permeability. The classical result in the case of the resistance/losses is Dowell’s equation, and there are analogous results for leakage inductance. This dissertation derives new equations …
Small-Signal Analysis Of Non-Isolated Ćuk Dc-Dc Converter, Lokesh Kathi
Small-Signal Analysis Of Non-Isolated Ćuk Dc-Dc Converter, Lokesh Kathi
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In the future, renewable energy sources will be the primary energy sources due to non-renewable energy resources depletion. Having a sustainable energy source as an input voltage source for the electrical system is essential. Its applications can be widely used in hybrid solar-wind energy systems, electric vehicles, etc. This converter is invented and named after by Slobodan Cuk. An analysis describing a detailed steady-state operation of the non-isolated Cuk converter operating in continuous-conduction mode (CCM) is provided. The expected steady-state current and voltage waveforms across different components of the converter are analytically derived. Design equations for the converter are provided. …
Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin
Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin
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Military aircraft systems’ power losses are occurring during the loading operations; loading and unloading causes the aircraft systems to lose power. The primary aircraft power source is provided by a 400Hz Ground Power Units (GPU). This GPU provides power to interior lighting, the aircraft cargo compartment, and other electrical systems (i.e. bus). The issues are during loading and unloading on the aircraft, which causes dropout of aircraft power supplied by the external 400Hz GPU. The majority of the military aircraft require a high voltage and a high current with a 270V power output. This thesis analyzes using Feed-Forward PWM Boost …
Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr.
Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr.
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Synthetic aperture ladar (SAL) is an emerging remote sensing technology capable of providing high-resolution, interpretable, and timely imagery. SAL and synthetic aperture radar (SAR) are similar in that they provide high-resolution imagery suitable for a wide-variety of applications beyond the diffraction limit of the real aperture. Several advantages of SAL are; realistic imagery resulting from diffuse scattering of optically-rough objects, fine directionality of laser beam making the technology inherently low probability-of-detect, and shorter synthetic aperture collection times, all of which result from operating at optical as opposed to RF wavelengths. With the dramatic decrease in wavelength, SAL systems become more …
Comparing Rf Fingerprinting Performance Of Hobbyist And Commercial-Grade Sdrs, Travis R. Smith
Comparing Rf Fingerprinting Performance Of Hobbyist And Commercial-Grade Sdrs, Travis R. Smith
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Radio Frequency Fingerprinting (RFF) research typically uses expensive, laboratory grade receivers which have high dynamic range, very stable oscillators, large instantaneous bandwidth, multi-rate sampling, etc. In this study, the RFF effectiveness of lower grade receivers is considered. Using software-defined radios (SDRs) of different cost and performance, a linear regression model is developed to predict RFF performance. Unlike two previous studies of SDR effectiveness that used commercial and lab-grade SDRs, the experiment here focused on hobbyist and commercial-grade SDRs (RTL-SDR, B200-mini, N210). A regression model is proposed for a generic SDR. Using a full-factorial experiment matrix, the gain, sample rate, and …
The Steady-State Analysis Of The Non-Isolated And Isolated Type Sepic Pwm Dc-Dc Converters For Ccm, Anuroop Reddy Dasari
The Steady-State Analysis Of The Non-Isolated And Isolated Type Sepic Pwm Dc-Dc Converters For Ccm, Anuroop Reddy Dasari
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The purpose of this thesis is to develop the theory for analysing and designing the non-isolated and isolated type of SEPIC converters for continuous conduction mode (CCM). The non-isolated converter has single output. The isolated converter considered has two cases: single output and multi-output. The principle of operation of each circuit is explained during different time intervals of the switching cycle. The analytical expressions for various characteristics of the circuits are derived, such as: MV DC and MIDC of the lossless and lossy converter; average and peak-to-peak currents through the inductors, primary and secondary windings of the transformer; average and …
Analytical Approach To Multi-Objective Joint Inference Control For Fixed Wing Unmanned Aerial Vehicles, Julian L. Casey
Analytical Approach To Multi-Objective Joint Inference Control For Fixed Wing Unmanned Aerial Vehicles, Julian L. Casey
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Fixed-wing Unmanned Aerial Vehicles (UAVs) have been found highly useful in various environments, including military and law enforcement. With the increased use of fixed-wing UAVs, there becomes an increased need to optimize the resources available. One approach to resource management is to create multi-objective flights. This thesis presents the design, analysis, and experimental implementation of multi-objective resource management for the resource of Range, distance available to the UAV, from the viewpoint of Intelligence Surveillance and Reconnaissance (ISR). First, a Simulation Environment is created capable of tracking multiple fixed-wing UAVs and to allow for the UAVs’ being controlled by an externally …
Online Clustering With Bayesian Nonparametrics, Matthew D. Scherreik
Online Clustering With Bayesian Nonparametrics, Matthew D. Scherreik
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Clustering algorithms, such as Gaussian mixture models and K-means, often require the number of clusters to be specified a priori. Bayesian nonparametric (BNP) methods avoid this problem by specifying a prior distribution over the cluster assignments that allows the number of clusters to be inferred from the data. This can be especially useful for online clustering tasks, where data arrives in a continuous stream and the number of clusters may dynamically change over time. Classical BNP priors often overestimate the number of clusters, however, leading researchers to develop new priors with more control over this tendency. To date, BNP algorithms …
Logistic Function Based Nonlinear Modeling And Circuit Analysis Of The Bipolar Vacancy Migration Memristor, Isaac P. Abraham
Logistic Function Based Nonlinear Modeling And Circuit Analysis Of The Bipolar Vacancy Migration Memristor, Isaac P. Abraham
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Memristor is an acronym for memory resistor. Memristors promise to be building blocks for high density memory and analog computation. Hewlett Packard’s announcement in 2008 of having fabricated a memristor on an integrated circuit scale has created a tangible excitement in this field. Understanding and exploiting the full potential of these devices requires good compact models. Symbolic modeling provides a balance between achieving accurate empirical fit and generating closed form expressions. This dissertation simplifies the transport equation into a variable coefficient advection equation, very similar to a Burgers’ equation traditionally used in fluid dynamics. The Burgers’-like model reveals the dual …