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2011

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Modeling Of Linear Induction Machines For Analysis And Control, Armando Jose Sinisterra Jan 2011

Modeling Of Linear Induction Machines For Analysis And Control, Armando Jose Sinisterra

Electronic Theses and Dissertations 2010 - 2019

In this thesis, the analysis of the dynamic response of a Linear Induction Motor as an electromechanical system is done, accounting for all the governing equations implied in the process which are used to develop the corresponding simulation models. Once this model is presented, a feedback control system is implemented in order to analyze the controlled response of the motor, considering the applications and conditions analogue to aircraft launcher systems. Also a comparison between the Linear and Rotary induction motors describing the differences, similarities and equivalences will be developed.

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Multi-Site Case Study Of A Professional Learning Community Model: The Impact Of Learning Team Meetings On Teacher Practice And Student Achievement From The Perspective Of Teachers And Instructional Leaders, Ora. Meles Jan 2011

Multi-Site Case Study Of A Professional Learning Community Model: The Impact Of Learning Team Meetings On Teacher Practice And Student Achievement From The Perspective Of Teachers And Instructional Leaders, Ora. Meles

Electronic Theses and Dissertations 2010 - 2019

The purpose of this study was to examine the impact of the implementation of a structured professional learning community model referred to as Learning Team Meetings (LTMs) on teacher practice and student achievement from the perspective of teachers and instructional leaders at high-need schools. To accomplish this purpose, a multi-site case study was conducted at three school sites (an elementary, middle, and high school) all within the same region of one of the largest urban school districts in South Florida. Qualitative research methods, including one-on-one observations, interviews, focus groups, and review of documents were utilized to analyze, contrast, and compare …

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Notes On A Liminal State, Patricia. Straub Jan 2011

Notes On A Liminal State, Patricia. Straub

Electronic Theses and Dissertations 2010 - 2019

Notes on a Liminal State is a collection of poetry prepared in partial fulfillment of the requirements for the degree of Master of Fine Arts in writing at Florida Atlantic University. While the poems cover a variety of topics, recurring themes include a mother's decline due to Alzheimer's Disease, infertility, adoption, and the observation of rural landscapes. The poems do not adhere to any single form.

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Nonlinear Resonance, Carey. Witkov Jan 2011

Nonlinear Resonance, Carey. Witkov

Electronic Theses and Dissertations 2010 - 2019

Sustained resonance in a linear oscillator is achievable with a drive whose constant frequency matches the resonant frequency of the oscillator. In oscillators with nonlinear restoring forces, i.e., Dung-type oscillators, resonant frequency changes with amplitude, so a constant frequency drive generates a beat oscillation instead of sustained resonance. Dung-type oscillators can be driven into sustained resonance, called autoresonance (AR), when drive frequency is swept in time to match the changing resonant frequency of the oscillator. It is found that near-optimal drive linear sweep rates for autoresonance can be estimated from the beat oscillation resulting from constant frequency excitation. Specically, a …

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Novel Nn Paradigm For The Prediction Of Hematocrit Value During Blood Transfusion, Jay. Thakkar Jan 2011

Novel Nn Paradigm For The Prediction Of Hematocrit Value During Blood Transfusion, Jay. Thakkar

Electronic Theses and Dissertations 2010 - 2019

During the Leukocytapheresis (LCAP) process used to treat patients suffering from acute Ulcerative Colitis, medical practitioners have to continuously monitor the Hematocrit (Ht) level in the blood to ensure it is within the acceptable range. The work done, as a part of this thesis, attempts to create an early warning system that can be used to predict if and when the Ht values will deviate from the acceptable range. To do this we have developed an algorithm based on the Group Method of Data Handling (GMDH) and compared it to other Neural Network algorithms, in particular the Multi Layer Perceptron …

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Numerical Simulation And Prediction Of Loads In Marine Current Turbine Full-Scale Rotor Blades, Junior. Senat Jan 2011

Numerical Simulation And Prediction Of Loads In Marine Current Turbine Full-Scale Rotor Blades, Junior. Senat

Electronic Theses and Dissertations 2010 - 2019

Marine current turbines are submerged structures and subjected to loading conditions from both the currents and wave effects. The associated phenomena posed significant challenge to the analyses of the loading response of the rotor blades and practical limitations in terms of device location and operational envelopes. The effect of waves on marine current turbines can contribute to the change of flow field and pressure field around the rotor and hence changes the fluid forces on the rotor. However, the effect of the waves on the rotor depends on the magnitude and direction of flow velocity that is induced by the …

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Permutation-Based Data Compression, Amalya Mihnea Jan 2011

Permutation-Based Data Compression, Amalya Mihnea

Electronic Theses and Dissertations 2010 - 2019

The use of permutations in data compression is an aspect that is worthy of further exploration. The work that has been done in video compression based on permutations was primarily oriented towards lossless algorithms. The study of previous algorithms has led to a new algorithm that could be either lossless or lossy, for which the amount of compression and the quality of the output can be controlled. The lossless version of our algorithm performs close to lossy versions of H.264 and it improves on them for the majority of the videos that we analyzed. Our algorithm could be used in …

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Predictors Of Scientific Understanding Of Middle School Students, Joshua Matthew Strate Jan 2011

Predictors Of Scientific Understanding Of Middle School Students, Joshua Matthew Strate

Electronic Theses and Dissertations 2010 - 2019

The purpose of this study was to determine if middle school student scientific understanding could be predicted by the variables: standardized 5th grade score in science, standardized 5th grade score in mathematics, standardized 5th grade score in reading, student attitude towards science, socioeconomic status, gender, and ethnicity. The areas of the comprehensive literature review were trends in science learning and teaching, research in the K-12 science education arena, what factors have influenced K-12 science education, scientific understanding, what research has been done on K-12 scientific understanding, and what factors have influenced science understanding in the K-12 arenas. Based on the …

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Reading Strategies In Secondary Social Studies, Carmen L. Newstreet Jan 2011

Reading Strategies In Secondary Social Studies, Carmen L. Newstreet

Electronic Theses and Dissertations 2010 - 2019

This quantitative study investigated the relationship between high school social studies teachers' reading professional development through Project CRISS: Creating Independence through Student-Owned Strategies (CRISS) and the implementation of active reading strategies in the classroom. Quantitative data were collected through an online survey in order to provide a comprehensive picture of high school social studies teachers' self-reported classroom practices relating to the use of active prereading, during-reading, and postreading strategies. Additionally, the survey asked teachers to self-report their observations of student independent implementation of the same active reading strategies. These data were used to provide an in-depth look that expanded on …

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Reliability-Based Fatigue Design Of Marine Current Turbine Rotor Blades, Shaun. Hurley Jan 2011

Reliability-Based Fatigue Design Of Marine Current Turbine Rotor Blades, Shaun. Hurley

Electronic Theses and Dissertations 2010 - 2019

The study presents a reliability-based fatigue life prediction model for the ocean current turbine rotor blades. The numerically simulated bending moment ranges based on the measured current velocities off the Southeast coast line of Florida over a one month period are used to reflect the short-term distribution of the bending moment ranges for an idealized marine current turbine rotor blade. The 2-parameter Weibull distribution is used to fit the short-term distribution and then used to obtain the long-term distribution over the design life. The long-term distribution is then used to determine the number of cycles for any given bending moment …

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Revisiting Leisure Activities And The Risk Of Dementia In The Elderly With Special Focus On Dancing, Carrie. Stevens Jan 2011

Revisiting Leisure Activities And The Risk Of Dementia In The Elderly With Special Focus On Dancing, Carrie. Stevens

Electronic Theses and Dissertations 2010 - 2019

Data was provided by researchers of the Einstein Aging Study (EAS) of the Albert Einstein College of Medicine, Yeshiva University whom statistically analyzed data from the Bronx Aging Study cohort, concluding that participation in cognitive leisure activities and one physical activity, dancing, were associated with a reduced risk of dementia [1]. We explore data from a second (the EAS) cohort, utilizing Cox Proportional-Hazards and extended Cox regression [13]. Cognitive leisure activities in general, and particularly doing crossword puzzles, reading books, watching television, and emailing are associated with a reduced risk of dementia. Doing aerobics, learning computer programming, babysitting, dancing, jogging …

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Risk-Evaluation In Clinical Diagnostic Studies, Alice Norm Dupont Jan 2011

Risk-Evaluation In Clinical Diagnostic Studies, Alice Norm Dupont

Electronic Theses and Dissertations 2010 - 2019

The efforts addressed in this thesis refer to applying nonlinear risk predictive techniques based on logistic regression to medical diagnostic test data. This study is motivated and pursued to address the following: 1. To extend logistic regression model of biostatistics to medical informatics 2. Computational preemptive and predictive testing to determine the probability of occurrence (p) of an event by fitting a data set to a (logit function) logistic curve: Finding upper and lower bounds on p based on stochastical considerations 3. Using the model developed on available (clinical) data to illustrate the bounds-limited performance of the prediction. Relevant analytical …

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Short Sea Shipping Cost Benefit Analysis Using Mathematical Modeling, Alvaro. Galletebeitia Jan 2011

Short Sea Shipping Cost Benefit Analysis Using Mathematical Modeling, Alvaro. Galletebeitia

Electronic Theses and Dissertations 2010 - 2019

With congestion, environmental Impact, and the price of oil becoming topics that influence businesses and individuals in a daily basis, measures need to be undertaken in order to accommodate the growing demand for freight transportation. By directing many of the trucks travelling along the National Highways Systems to the Marine Highway corridors developed by the U.S. Maritime Administrations, many of the problems can be addressed in the Short and Medium terms. In order to do so, Short Sea Shipping, through the use of Ro/Ro (Roll-on/Roll-off) Vessels, needs to be implemented. Although the environmental and congestion reducing benefits are considerable, the …

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Simulating The Dynamic Interaction Of An Auv And Towed Magnetometer, Lea Gabrielle Miller Jan 2011

Simulating The Dynamic Interaction Of An Auv And Towed Magnetometer, Lea Gabrielle Miller

Electronic Theses and Dissertations 2010 - 2019

A magnetometer with a sensitivity of 0.01nT will be towed through the thermocline by a 2.87 meter long, 0.533 meter diameter autonomous underwater vehicle (AUV) to measure the magnetic fluctuations generated by oceanic internal waves. At this point, no research has been found that suggests towed magnetometer measurements have been done using an AUV. Simulations of the AUV, tow cable, and towfish are performed to provide an understanding of the effects of changing different input parameters, such as towing speed (0.5-2m/s), cable length (5-15m), vehicle trajectory (circle and vertical zig zag maneuvers), and current (0.25-1.25m/s). The AUV-cabletowfish system and equations …

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Simulations And Feedback Control Of Nonlinear Coupled Electromechanical Oscillators For Energy Conversion Applications, Dimitrios. Psarrou Jan 2011

Simulations And Feedback Control Of Nonlinear Coupled Electromechanical Oscillators For Energy Conversion Applications, Dimitrios. Psarrou

Electronic Theses and Dissertations 2010 - 2019

This thesis discusses the coupling of a mechanical and electrical oscillator, an arrangement that is often encountered in mechatronics actuators and sensors. The dynamics of this coupled system is mathematically modeled and a low pass equivalent model is presented. Numerical simulations are then performed, for various input signals to characterize the nonlinear relationship between the electrical current and the displacement of the mass. Lastly a framework is proposed to estimate the mass position without the use of a position sensor, enabling the sensorless control of the coupled system and additionally providing the ability for the system to act as an …

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Statistical Broadcast Protocol Design For Vanet, Michael J. Slavik Jan 2011

Statistical Broadcast Protocol Design For Vanet, Michael J. Slavik

Electronic Theses and Dissertations 2010 - 2019

This work presents the development of the Statistical Location-Assisted Broadcast (SLAB) protocol, a multi-hop wireless broadcast protocol designed for vehicular ad-hoc networking (VANET). Vehicular networking is an important emerging application of wireless communications. Data dissemination applications using VANET promote the ability for vehicles to share information with each other and the wide-area network with the goal of improving navigation, fuel consumption, public safety, and entertainment. A critical component of these data dissemination schemes is the multi-hop wireless broadcast protocol. Multi-hop broadcast protocols for these schemes must reliably deliver broadcast packets to vehicles in a geographically bounded region while consuming as …

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Stability Analysis Of Feature Selection Approaches With Low Quality Data, Wilker. Altidor Jan 2011

Stability Analysis Of Feature Selection Approaches With Low Quality Data, Wilker. Altidor

Electronic Theses and Dissertations 2010 - 2019

One of the greatest challenges to data mining is erroneous or noisy data. Several studies have noted the weak performance of classification models trained from low quality data. This dissertation shows that low quality data can also impact the effectiveness of feature selection, and considers the effect of class noise on various feature ranking techniques. It presents a novel approach to feature ranking based on ensemble learning and assesses these ensemble feature selection techniques in terms of their robustness to class noise. It presents a noise-based stability analysis that measures the degree of agreement between a feature ranking techniques output …

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Stochastic Optimization Of Energy For Multi-User Wireless Networks Over Fading Channels, Di Wang Jan 2011

Stochastic Optimization Of Energy For Multi-User Wireless Networks Over Fading Channels, Di Wang

Electronic Theses and Dissertations 2010 - 2019

Wireless devices in wireless networks are powered typically by small batteries that are not replaceable nor recharged in a convenient way. To prolong the operating lifetime of networks, energy efficiency is indicated as a critical issue and energy-efficient resource allocation designs have been extensively developed. We investigated energy-efficient schemes that prolong network operating lifetime in wireless sensor networks and in wireless relay networks. In Chapter 2, the energy-efficient resource allocation that minimizes a general cost function of average user powers for small- or medium-scale wireless sensor networks, where the simple time-division multiple-access (TDMA) is adopted as the multiple access scheme. …

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Source Speed Estimation Using A Pilot Tone In A High-Frequency Acoustic Modem, Poorani. Kathiroli Jan 2011

Source Speed Estimation Using A Pilot Tone In A High-Frequency Acoustic Modem, Poorani. Kathiroli

Electronic Theses and Dissertations 2010 - 2019

This thesis proposes to estimate the speed of a moving acoustic source by either linear or non linear processing of the resulting Doppler shift present in a high-frequency pilot tone. The source is an acoustic modem (Hermes) which currently uses moving average to estimate and compensate for Doppler shift. A new auto regressive approach to Doppler estimation (labeled IIR method in the text) promises to give a better estimate. The results for a simulated peak velocity of 2 m/s in the presence of additive noise showed an RMSE of 0.23 m/s using moving average vs. 0.00018 m/s for the auto …

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Study Of Persistence Of Undergraduate Women Majoring In Engineering And Math, Jessica. Pena-Lopez Jan 2011

Study Of Persistence Of Undergraduate Women Majoring In Engineering And Math, Jessica. Pena-Lopez

Electronic Theses and Dissertations 2010 - 2019

The purpose of this study was to identify factors that are associated with encourage the persistence of undergraduate women majoring in Engineering and Math (EM) at Florida Atlantic University, University of Central Florida, and University of South Florida. The persistence factors were examined through an analysis of university data and the use of a survey for enrolled senior standing students who declared their first major in engineering or math. Both quantitative and qualitative methods were utilized to collect and analyze data from the three sites. Factor analysis and logistic regression were used to analyze the quantitative data. The quantitative data …

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Study On Neural Conduction As In Myelinated Structure Under Pathological Conditions, George J. Morales Jan 2011

Study On Neural Conduction As In Myelinated Structure Under Pathological Conditions, George J. Morales

Electronic Theses and Dissertations 2010 - 2019

A method for modeling and simulating neural action potential (AP) propagation along the length of an axon containing a number of Ranvier nodes is proposed in this dissertation. A system identification approach is adopted to represent node of Ranvier (NR) response to current pulse stimulus in the form of transfer function representations for NR excitability. Segments of myelinated internodal (IN) and NR regions are cascaded, representing the remaining downstream axon after a site-of-stimulus introduction of an external current pulse. This cascading network is used to simulate "cable" properties and signal propagation along the length of the axon. This work proposes …

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Synchronization Of Coupled Semiconductor Lasers, Michael S. London Jan 2011

Synchronization Of Coupled Semiconductor Lasers, Michael S. London

Electronic Theses and Dissertations 2010 - 2019

The synchronization of coupled semiconductor lasers with delay is investigated by numerical simulations of the nonlinear dynamic models complemented by a stability analysis of the linearized system. The equations used in the dissertation are based on the well known "Lang-Kobayashi" model modified to include unidirectional and bidirectional coupling. Stability diagrams are calculated and supplemented by numerically integrated time series. Synchronization is determined and quantified by computing the cross-correlation function. It is found that synchronized states are achievable for a wide range of coupling constants and delay times. These findings have implications for experiment and technological applications, notably in cryptography.

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System Identification Methodology For A Wave Adaptive Modular Unmanned Surface Vehicle, Janine L. Mask Jan 2011

System Identification Methodology For A Wave Adaptive Modular Unmanned Surface Vehicle, Janine L. Mask

Electronic Theses and Dissertations 2010 - 2019

The design, implementation, and testing of an experimental setup intended to evaluate the dynamic maneuvering performance of the Wave Adaptive Modular Vessel (WAM-V) class USV12, a 3.7 meter unmanned surface vehicle (USV) is described. A comprehensive sensor package was designed, fabricated and assembled to record the vehicle's dynamic response to various control inputs. All subsystems were fabricated and installed on a test vehicle, GUSS, and full system, open-loop maneuvering tests were conducted to show validity of data collection technique. Simulations were performed using model parameters found in the literature to create a "simulated experimental" data set, upon which system identification …

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Systematic Evaluation Of Object Detection And Recognition Approaches With Context Capabilities, Urbina Rafael J Giusti Jan 2011

Systematic Evaluation Of Object Detection And Recognition Approaches With Context Capabilities, Urbina Rafael J Giusti

Electronic Theses and Dissertations 2010 - 2019

Contemporary computer vision solutions to the problem of object detection aim at incorporating contextual information into the process. This thesis proposes a systematic evaluation of the usefulness of incorporating knowledge about the geometric context of a scene into a baseline object detection algorithm based on local features. This research extends publicly available MATLABRª implementations of leading algorithms in the field and integrates them in a coherent and extensible way. Experiments are presented to compare the performance and accuracy between baseline and context-based detectors, using images from the recently published SUN09 dataset. Experimental results demonstrate that adding contextual information about the …

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Technology And Fifth Grade Teaching, Debbie. Beaudry Jan 2011

Technology And Fifth Grade Teaching, Debbie. Beaudry

Electronic Theses and Dissertations 2010 - 2019

This mixed methods study investigated 5th-grade teachers' reported use of computer technology and variables that have been identified by researchers as affecting teachers' use of technology, including professional development activities, physical access to computer technology, and technical and instructional support provided for teachers. Quantitative data were collected from 80 5th-grade teachers from a Florida public school district through an online survey in which teachers reported how frequently they used and had their students use computer technology for 27 different purposes. The teachers also reported the amount of emphasis those 27 different topics received during their technology-related professional development experiences, the …

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The Minimal Logarithmic Signature Conjecture, Nidhi. Singhi Jan 2011

The Minimal Logarithmic Signature Conjecture, Nidhi. Singhi

Electronic Theses and Dissertations 2010 - 2019

The minimal logarithmic signature conjecture states that in any finite simple group there are subsets Ai, 1 i s such that the size jAij of each Ai is a prime or 4 and each element of the group has a unique expression as a product Qs i=1 ai of elements ai 2 Ai. Logarithmic signatures have been used in the construction of several cryptographic primitives since the late 1970's [3, 15, 17, 19, 16]. The conjecture is shown to be true for various families of simple groups including cyclic groups, An, PSLn(q) when gcd(n; q 1) is 1, 4 or …

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Theoretical Study Of Binary Alloy Thin Film Growth, Mark R. Bouwens Jan 2011

Theoretical Study Of Binary Alloy Thin Film Growth, Mark R. Bouwens

Electronic Theses and Dissertations 2010 - 2019

Computer simulations of the growth of binary alloy thin films in two and three dimensions were performed using an extension of the Solid on Solid model. Snapshots for a range of interactions and diffusion rates are presented and critically compared to experiment. A wide variety of distinct phases is identified and their growth conditions analyzed. These findings are summarized in a phase diagram. In addition, a fractal analysis of the domains is performed. It is found that for negative interactions the islands are two-dimensional, while for positive interactions, regardless of diffusion rate, a fractal dimension of 1.78 is obtained.

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Understanding Group Emotional Intelligence In The Public Sector, Umar. Ghuman Jan 2011

Understanding Group Emotional Intelligence In The Public Sector, Umar. Ghuman

Electronic Theses and Dissertations 2010 - 2019

In recent years behaviroal management literature has created and utilized the concept of group emotional intelligence in work groups and work teams. This dissertation is a re-conceptualization and an empirical analysis of group emotional intelligence in the context of public administration work groups. This dissertation proposes a new conceptualization of GEI and utilizes it for the empirical measurement of GEI. By critically reviewing previous theoretical and empirical literature on group level phenomena and their measurement, this dissertation offers a re-conceptualization of group emotional intelligence. it also defines group emotional intelligence (GEI), creates a model for GEI, provides an empirical means …

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University Educational Leadership Technology Course Syllabi Alignment With State And National Technology Standards, Angela M. Iudica Jan 2011

University Educational Leadership Technology Course Syllabi Alignment With State And National Technology Standards, Angela M. Iudica

Electronic Theses and Dissertations 2010 - 2019

The purpose of this study was to determine the degree of alignment to national and state standards in public and private university educational leadership certification programs in the state of Florida. The standards used were the National Educational Technology Standards for Administrators (NETS-A) and the Florida Principal Leadership Standard for Technology (FPLST). A total of 16 university technology leadership course syllabi were examined. Nine syllabi were obtained from 11 public universities and seven were obtained from 11 private universities in Florida. Syllabi were examined using rubrics and assigned to one of three categories: definitely aligned, somewhat aligned and not aligned. …

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Very High Frequency Mimo Underwater Acoustic Communications In Ports And Shallow Waters, Gaultier. Real Jan 2011

Very High Frequency Mimo Underwater Acoustic Communications In Ports And Shallow Waters, Gaultier. Real

Electronic Theses and Dissertations 2010 - 2019

This thesis presents the development of a Multiple-Input Multiple-Output (MIMO) capable high bit rate acoustic modem operating at high frequencies. A MIMO channel estimation technique based on Least-Squares (LS) estimation is developed here. Channel deconvolution is completed using a Minimum Mean-Square Error (MMSE) Linear Equalizer (LE). An Interference Cancellation Linear Equalizer (ICLE) is used to provide the theoretical limit of the MIMO deconvolution process. The RMSE of the channel estimation process was 1.83 % and 6.1810 %, respectively for simulated and experimental data. Using experimental data, the RMSE before MIMO deconvolution process was 141.3 % and dropped down to 60.224 …

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