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A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee 2016 University of Dayton

A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee

Monish R. Chatterjee

The present thesis attempts to give a concise and critical account of the evolution of the echo phenomena over the last thirty years. Starting with spin and photon echoes, which were among the earliest to be observed and studied, the thesis explores the experimental findings and the models proposed in connection with the more contemporary echo experiments, viz. those involving electroacoustic or polarization echoes in single and polycrystalline piezoelectric materials and in powders. Although the investigations regarding the various mechanisms of short and long term echo formation are by no means complete, a coherent picture is beginning to emerge as ...


A Transfer Function Based Frequency Model For Propagation Of A Chaos Wave Through Modified Von Karman Turbulence Under Various Chaos And Turbulence Conditions, Monish Ranjan Chatterjee, Fathi H.A. Mohamed 2016 University of Dayton

A Transfer Function Based Frequency Model For Propagation Of A Chaos Wave Through Modified Von Karman Turbulence Under Various Chaos And Turbulence Conditions, Monish Ranjan Chatterjee, Fathi H.A. Mohamed

Monish R. Chatterjee

Complex phasor fields for electromagnetic wave propagation through von Karman turbulence and acousto-optic RF chaos are derived en route to the effective transfer function between chaos and narrow turbulence. Results are tested for several turbulence and chaos conditions.


Chaotic Bandgaps In Hybrid Acousto-Optic Feedback And Their Implications, Monish Ranjan Chatterjee, Mohammed A. Al-Saedi 2016 University of Dayton

Chaotic Bandgaps In Hybrid Acousto-Optic Feedback And Their Implications, Monish Ranjan Chatterjee, Mohammed A. Al-Saedi

Monish R. Chatterjee

The nonlinear dynamics of a hybrid acousto-optic device was examined from the perspective of the Lyapunov exponent (LE) and bifurcation maps. The plots for LE versus system parameters and bifurcation maps have recently been examined against known simulation results including chaotic encryption experiments [1]. It is verified that the "loop gain" (feedback gain (β) times incident light amplitude (Iin) needs to be greater than one as a necessary , but not sufficient condition for the onset of chaos.

It is found that for certain combinations of β, Iin, net bias voltage (αtοt), and the initial value of the first-order scattered light ...


Consideration Of Dispersion And Group Velocity Dispersion In The Determination Of Velocities Of Electromagnetic Propagation, Monish Ranjan Chatterjee, Partha P. Banerjee 2016 University of Dayton

Consideration Of Dispersion And Group Velocity Dispersion In The Determination Of Velocities Of Electromagnetic Propagation, Monish Ranjan Chatterjee, Partha P. Banerjee

Partha Banerjee

Electromagnetic (EM) propagation velocities play an important role in the determination of power and energy flow in materials and interfaces. It is well known that group and phase velocities need to be in opposition in order to achieve negative refractive index.

Recently, we have shown that considerable differences may exist in phase, group and signal/energy velocities for normal and anomalous dispersion, especially near dielectric resonances. This paper examines the phase and group velocities in the presence of normal and anomalous dispersion, and group velocity dispersion (GVD), which requires introduction of the second order coefficient in the permittivity and permeability ...


Examination Of Focused Beam Propagation Through A Finite Non-Reciprocal Planar Chiral Slab Using Complex Fresnel Coefficients And Dual Transforms, Monish Ranjan Chatterjee, Sumit Nema, Partha P. Banerjee 2016 University of Dayton

Examination Of Focused Beam Propagation Through A Finite Non-Reciprocal Planar Chiral Slab Using Complex Fresnel Coefficients And Dual Transforms, Monish Ranjan Chatterjee, Sumit Nema, Partha P. Banerjee

Partha Banerjee

Recently, uniform plane wave propagation across a nonchiral-chiral interface was examined via the development of appropriate Fresnel coefficients. In this extension, propagation of focused uniform and profiled beams through a finite, planar nonreciprocal chiral slab is investigated using complex Fresnel coefficients via angular plane wave decomposition and dual transforms.


Investigation Of Negative Refractive Index In Reciprocal Chiral Materials, Monish Ranjan Chatterjee, Partha P. Banerjee, Pradeep R. Anugula 2016 University of Dayton

Investigation Of Negative Refractive Index In Reciprocal Chiral Materials, Monish Ranjan Chatterjee, Partha P. Banerjee, Pradeep R. Anugula

Partha Banerjee

It is well known that there exist both natural materials (such as milk or sugar solution) possessing chiral (or handed) properties, as well as an increasing list of man-made materials (such as sodium bromate) that exhibit chirality. One of the principal properties of chirality is that light of any arbitrary polarization, when propagating through a chiral material, splits up into two circular polarizations propagating in different directions. In the past decade or longer, researchers have investigated electromagnetic transverse (plane) wave propagation across a non-chiral/chiral interface, and determined the electromagnetic Fresnel coefficients for such propagation. Traditionally, such coefficients are derived ...


A System For Monitoring And Managing Indoor Air Quality And Environmental Conditions, Ali Ibrahim 2016 Boise State University

A System For Monitoring And Managing Indoor Air Quality And Environmental Conditions, Ali Ibrahim

Boise State University Theses and Dissertations

The quality of indoor air depends on different types of pollutant sources existing in a semi-enclosed environment. The sources can be biological, chemical, or toxic pollutants. These sources can cause health issues and discomfort for occupants. One of the indicators of poor indoor air quality is Carbon Dioxide (CO2). CO2 can be used to indicate the indoor air exchange rate. The lack of air exchange means higher levels of CO2. High levels of indoor particulates can also be an indication of poor air quality. Due to the lack of fresh air, air circulation, and air filtration, the ...


The Design And Validation Of A Wireless Bat-Mounted Sonar Recording System, Jeremy Joseph Langford 2016 University of Tennessee, Knoxville

The Design And Validation Of A Wireless Bat-Mounted Sonar Recording System, Jeremy Joseph Langford

Masters Theses

Scientists studying the behavior of bats monitor their echolocation calls, as their calls are important for navigation and feeding, but scientist are typically restricted to ground-based recording. Recording bat calls used for echolocation from the back of the bat as opposed to the ground offers the opportunity to study bat echolocation from a vantage otherwise only offered to the bats themselves. However, designing a bat mounted in-flight audio recording system, (bat-tag), capable of recording the ultra-sound used in bat echolocation presents a unique set of challenges. Chiefly, the bat-tag must be sufficiently light weight as to not overburden the bat ...


Channel Estimation Overhead Reduction For Downlink Fdd Massive Mimo Systems, Abderrahmane Mayouche 2016 University of Arkansas, Fayetteville

Channel Estimation Overhead Reduction For Downlink Fdd Massive Mimo Systems, Abderrahmane Mayouche

Theses and Dissertations

Massive multiple-input multiple-output (MIMO) is the concept of deploying a very large number of antennas at the base stations (BS) of cellular networks. Frequency-division duplexing (FDD) massive MIMO systems in the downlink (DL) suffer significantly from the channel estimation overhead. In this thesis, we propose a minimum mean square error (MMSE)-based channel estimation framework that exploits the spatial correlation between the antennas at the BS to reduce the latter overhead. We investigate how the number of antennas at the BS affects the channel estimation error through analytical and asymptotic analysis. In addition, we derive a lower bound on the ...


Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva 2016 University of Dayton

Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva

Monish R. Chatterjee

When a prerecorded cross-beam hologram is reconstructed (so-called edge-lit readout) with a uniform plane wave and a point source, the resulting exact solutions reveal Bessel-function-type diffracted beam profiles, which are fundamentally modified under weak propagational diffraction. The case of a profiled beam readout with propagational diffraction may be analyzed using a transfer function approach based on 2-D Laplace transforms. In a second series of investigations, dynamic readout from a cross-beam volume hologram recorded with two orthogonal uniform plane waves is considered for various dependences of the refractive index modulation with intensity. Typically, refractive index profiles that are proportional to the ...


Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay 2016 University of Dayton

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Electrical and Computer Engineering Faculty Publications

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii ...


Analysis And Implementation Of Communications Systems For Small Satellite Missions, Jason S. Harris 2016 Old Dominion University

Analysis And Implementation Of Communications Systems For Small Satellite Missions, Jason S. Harris

Electrical & Computer Engineering Theses & Disssertations

Nano satellites are becoming more and more popular space platforms due to their relatively low cost. Constellations of many of these small satellites are being launched for scientific and research purposes. This thesis has examined implementing a communications system for small satellites that can be used to maintain constant contact with satellites as they orbit the Earth. It analyzes the various components of a small satellite and how they integrate. It then discusses the different abstraction layers that will be required in order to support the same software architecture across various types of hardware. An orbital analysis was performed to ...


Plantmetabolomics.Org: Mass Spectrometry-Based Arabidopsis Metabolomics—Database And Tools Update, Preeti Bais, Stephanie M. Moon-Quanbeck, Basil J. Nikolau, Julie A. Dickerson 2016 Iowa State University

Plantmetabolomics.Org: Mass Spectrometry-Based Arabidopsis Metabolomics—Database And Tools Update, Preeti Bais, Stephanie M. Moon-Quanbeck, Basil J. Nikolau, Julie A. Dickerson

Basil Nikolau

The PlantMetabolomics (PM) database (http://www.plantmetabolomics.org) contains comprehensive targeted and untargeted mass spectrum metabolomics data for Arabidopsis mutants across a variety of metabolomics platforms. The database allows users to generate hypotheses about the changes in metabolism for mutants with genes of unknown function. Version 2.0 of PlantMetabolomics.org currently contains data for 140 mutant lines along with the morphological data. A web-based data analysis wizard allows researchers to select preprocessing and data-mining procedures to discover differences between mutants. This community resource enables researchers to formulate models of the metabolic network of Arabidopsis and enhances the research community ...


Performance Optimization Of Network Protocols For Ieee 802.11s-Based Smart Grid Communications, Nico Saputro 2016 Florida International University

Performance Optimization Of Network Protocols For Ieee 802.11s-Based Smart Grid Communications, Nico Saputro

FIU Electronic Theses and Dissertations

The transformation of the legacy electric grid to Smart Grid (SG) poses numerous challenges in the design and development of an efficient SG communications network. While there has been an increasing interest in identifying the SG communications network and possible SG applications, specific research challenges at the network protocol have not been elaborated yet. This dissertation revisited each layer of a TCP/IP protocol stack which basically was designed for a wired network and optimized their performance in IEEE 802.11s-based Advanced Metering Infrastructure (AMI) communications network against the following challenges: security and privacy, AMI data explosion, periodic simultaneous data ...


Prosense, Johnny Favazza II, Casey Glasgow, Matt Epperson 2016 California Polytechnic State University, San Luis Obispo

Prosense, Johnny Favazza Ii, Casey Glasgow, Matt Epperson

Computer Engineering

This project aims to gather advanced data sets from MEMS sensors and GPS and deliver it to the user, who can capitalize on the data. The once negligible half-degree difference of your board barreling down a wave can be recorded from a gyro and exploited for the perfect turn. The exact speed dreaded by longboarders where speed wobbles turn into a road rash can be analysed and consequently avoided. Ascertaining the summit of your flight using combined GPS sensors from the ski ramp allows for the correct timing of tricks. When it comes to pursuing excellence in professional sports, amateur ...


Pinpoint: Location Beacon And Tracking, Ezequiel Lopez III 2016 California Polytechnic State University, San Luis Obispo

Pinpoint: Location Beacon And Tracking, Ezequiel Lopez Iii

Computer Engineering

The purpose of Pinpoint was to create a device that can collect and transmit location information for multiple users on a wireless network. The device would be used to keep track of and communicate with other users nearby. The final design includes a touchscreen display as a graphical user interface (GUI), an XBee RF module for wireless networking, a GPS receiver for location tracking, and a Programmable System on a Chip (PSoC) to control the modules.


Underwater Optical Wireless Audio Transceiver, Angel Ayala 2016 California Polytechnic State University, San Luis Obispo

Underwater Optical Wireless Audio Transceiver, Angel Ayala

Electrical Engineering

Scuba diving carries risks that can endanger lives. Many of these risks are preventable. However, an underwater communication system can increase a diver’s safety. Along with providing safety, an underwater communication device can enhance the scuba diver’s enjoyment.

A low cost underwater optical wireless audio transceiver is designed. The project consists of the off-the-shelf parts that uses a microphone and speaker to transmit and receive sound. The project uses the concepts of visible light communications and pulse width modulation to transmit and receive sound. Although sound is commonly transmitted through ultrasound methods, visible light communications has several advantages ...


Analysis Of Various Algorithmic Approaches To Software-Based 1200 Baud Audio Frequency Shift Keying Demodulation For Aprs, Robert F. Campbell 2016 California Polytechnic State University, San Luis Obispo

Analysis Of Various Algorithmic Approaches To Software-Based 1200 Baud Audio Frequency Shift Keying Demodulation For Aprs, Robert F. Campbell

Master's Theses and Project Reports

Digital communications continues to be a relevant Field of study as new technologies appear and old methodologies get revisited or renovated. The goal of this research is to look into the old digital communication scheme of Bell 202 [67] used by APRS and improve software based demodulation performance. Improved performance is defined by being able to correctly decode more packets in an efficient, real time, manner. Most APRS demodulation is currently done using specialized hardware since that yields the best performance. This research shows that through using Sivan Toledo's javAX25 [72] software package, new demodulation algorithms can be implemented ...


Histogram Of Oriented Phase (Hop): A New Descriptor Based On Phase Congruency, Hussin Ragb, Vijayan K. Asari 2016 University of Dayton

Histogram Of Oriented Phase (Hop): A New Descriptor Based On Phase Congruency, Hussin Ragb, Vijayan K. Asari

Electrical and Computer Engineering Faculty Publications

In this paper we present a low level image descriptor called Histogram of Oriented Phase based on phase congruency concept and the Principal Component Analysis (PCA). Since the phase of the signal conveys more information regarding signal structure than the magnitude, the proposed descriptor can precisely identify and localize image features over the gradient based techniques, especially in the regions affected by illumination changes. The proposed features can be formed by extracting the phase congruency information for each pixel in the image with respect to its neighborhood. Histograms of the phase congruency values of the local regions in the image ...


An Adaptable Fuzzy-Based Model For Predicting Link Quality In Robot Networks., Christopher J. Lowrance 2016 University of Louisville

An Adaptable Fuzzy-Based Model For Predicting Link Quality In Robot Networks., Christopher J. Lowrance

Electronic Theses and Dissertations

It is often essential for robots to maintain wireless connectivity with other systems so that commands, sensor data, and other situational information can be exchanged. Unfortunately, maintaining sufficient connection quality between these systems can be problematic. Robot mobility, combined with the attenuation and rapid dynamics associated with radio wave propagation, can cause frequent link quality (LQ) issues such as degraded throughput, temporary disconnects, or even link failure. In order to proactively mitigate such problems, robots must possess the capability, at the application layer, to gauge the quality of their wireless connections. However, many of the existing approaches lack adaptability or ...


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