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Silent Communication Device, Christopher Wayne Schutter 2017 Calfornia Polytechnic State University - San Luis Obispo

Silent Communication Device, Christopher Wayne Schutter

Master's Theses and Project Reports

Oral communication has constituted as a necessary aspect of how people interact with one another, but there are always situations where this form of communication can create distractions, irritation, or even danger. Take for example, a student in a laboratory who needs to communicate effectively with a lab partner without creating a distraction to those trying to work around said student or a soldier on a battlefield who needs to relay information effectively to his or her comrades without revealing his or her position to the enemy. It becomes apparent that people need a more exclusive form of communication in ...


T1, T2, And Off-Resonance Mapping Using A Non-Linear Least-Squares Fit Of The Bssfp Signal, Meredith Taylor, Joseph Valentine, Steven Whitaker, Neal Bangerter 2017 Brigham Young University

T1, T2, And Off-Resonance Mapping Using A Non-Linear Least-Squares Fit Of The Bssfp Signal, Meredith Taylor, Joseph Valentine, Steven Whitaker, Neal Bangerter

Biomedical Engineering Western Regional Conference

The mapping of MR relaxation times has found a broad variety of applications in the study of disease. Unfortunately, the gold standards for acquiring T1 and T2 maps require long scan times, and are therefore more suited to 2D acquisitions with limited slices. For reasonable scan times, resolution is limited making these scans less useful for showing fine morphological detail. A rapid 3D sequence at higher resolutions that could be used to provide both morphological detail and relaxation time maps would be particularly useful. We propose a technique with potential to provide simultaneous band-free 3D datasets and estimates ...


Water Fat Separation With Multiple-Acquisition Bssfp Mri, Michael A. Mendoza 8232743, Joseph Valentine, Neal Bangerter 2017 Brigham Young University

Water Fat Separation With Multiple-Acquisition Bssfp Mri, Michael A. Mendoza 8232743, Joseph Valentine, Neal Bangerter

Biomedical Engineering Western Regional Conference

We present a technique that combines the advantages of bSSFP MRI with Dixon reconstruction in order to produce robust water fat separation with high SNR in a short imaging time, while simultaneously reducing banding artifacts that traditionally degrade image quality.


Accurate Acoustic Ranging System Using Android Smartphones, mohammadbagher fotouhi 2017 Virginia Commonwealth University

Accurate Acoustic Ranging System Using Android Smartphones, Mohammadbagher Fotouhi

Theses and Dissertations

ACCURATE ACOUSTIC RANGING SYSTEM USING ANDROID SMARTPHONES

By Mohammadbagher Fotouhi, Master of Science

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University

Virginia Commonwealth University 2017

Major Director: Dr. Ruixin Niu, Associate Professor of Department of Electrical and Computer Engineering

In this thesis, we present the design, implementation, and evaluation of an android ranging system, a high-accuracy acoustic-based ranging system which allows two android mobile phones to learn their physical distance from each other.

In this system we propose a practical solution for accurate ranging based on acoustic communication ...


Experimental Investigation Of Reading Passive Uhf Tags In A Multi-Tag Environment, Yi Zhou 2017 University of Kentucky

Experimental Investigation Of Reading Passive Uhf Tags In A Multi-Tag Environment, Yi Zhou

Theses and Dissertations--Mechanical Engineering

Recently, the Internet of things (IoT) has emerged as a promising solution for several industrial applications. One of the key components in IoT is passive radio frequency identification (RFID) tags which do not require a power source for operations. Specifically, ultra-high frequency (UHF) tags are studied in this paper. However, due to factors such as tag-to-tag interference and inaccurate localization, RFID tags that are closely spaced together are difficult to detect and program accurately with unique identifiers. This thesis investigates several factors that affect the ability to encode a specific tag with unique information in the presence of other tags ...


Time-Frequency Masking Performance For Improved Intelligibility With Microphone Arrays, Joshua P. Morgan 2017 University of Kentucky

Time-Frequency Masking Performance For Improved Intelligibility With Microphone Arrays, Joshua P. Morgan

Theses and Dissertations--Electrical and Computer Engineering

Time-Frequency (TF) masking is an audio processing technique useful for isolating an audio source from interfering sources. TF masking has been applied and studied in monaural and binaural applications, but has only recently been applied to distributed microphone arrays. This work focuses on evaluating the TF masking technique's ability to isolate human speech and improve speech intelligibility in an immersive "cocktail party" environment. In particular, an upper-bound on TF masking performance is established and compared to the traditional delay-sum and general sidelobe canceler (GSC) beamformers. Additionally, the novel technique of combining the GSC with TF masking is investigated and ...


Detection Of Fatigue Damage In Shear Connections Using Acoustic Wave Propagation, Zichao Wang 2017 Michigan Technological University

Detection Of Fatigue Damage In Shear Connections Using Acoustic Wave Propagation, Zichao Wang

Dissertations, Master's Theses and Master's Reports

Fatigue damage is an important concern in structural steel connections where frequent load reversals are expected. Detection of fatigue damage is typically done with infrequent visual inspections that are subjective and limited to surface features. A permanent embedded structural health monitoring (SHM) system could be helpful in detecting damage as it occurs. Current methods for detecting fatigue damage include inference of fatigue life expended through cycle counting from long-term strain measurement campaigns, and through short-term impedance measurements. The first approach has the advantage that it is relatively simple from an algorithmic point of view, but it is an indirect measure ...


High Performance Multiview Video Coding, Caoyang Jiang 2017 Michigan Technological University

High Performance Multiview Video Coding, Caoyang Jiang

Dissertations, Master's Theses and Master's Reports

Following the standardization of the latest video coding standard High Efficiency Video Coding in 2013, in 2014, multiview extension of HEVC (MV-HEVC) was published and brought significantly better compression performance of around 50% for multiview and 3D videos compared to multiple independent single-view HEVC coding. However, the extremely high computational complexity of MV-HEVC demands significant optimization of the encoder. To tackle this problem, this work investigates the possibilities of using modern parallel computing platforms and tools such as single-instruction-multiple-data (SIMD) instructions, multi-core CPU, massively parallel GPU, and computer cluster to significantly enhance the MVC encoder performance. The aforementioned computing tools ...


Explorations Into Machine Learning Techniques For Precipitation Nowcasting, Aditya Nagarajan 2017 University of Massachusetts Amherst

Explorations Into Machine Learning Techniques For Precipitation Nowcasting, Aditya Nagarajan

Masters Theses

Recent advances in cloud-based big-data technologies now makes data driven solutions feasible for increasing numbers of scientific computing applications. One such data driven solution approach is machine learning where patterns in large data sets are brought to the surface by finding complex mathematical relationships within the data. Nowcasting or short-term prediction of rainfall in a given region is an important problem in meteorology. In this thesis we explore the nowcasting problem through a data driven approach by formulating it as a machine learning problem.

State-of-the-art nowcasting systems today are based on numerical models which describe the physical processes leading to ...


System For Workout Information Management, Mark Archual, Ethan E. Schweinsberg 2017 The University of Akron

System For Workout Information Management, Mark Archual, Ethan E. Schweinsberg

Honors Research Projects

Power racks are a weight machine used by swimmers to provide resistance while they swim away from a wall toward the center of the pool. The objective of this project is to build a modular data system that can be added to these machines to record and log quantitative information during their use. This information will be stored on a web server, and made available to the user for analysis and visualization through a web application. Workout data can also be downloaded and interpreted at a later time, independent of the web application. The data system should be water resistant ...


Topography Measurements Using An Airborne Ka-Band Fmcw Interferometric Synthetic Aperture Radar, Kan Fu 2017 University of Massachusetts - Amherst

Topography Measurements Using An Airborne Ka-Band Fmcw Interferometric Synthetic Aperture Radar, Kan Fu

Doctoral Dissertations

Radar interferometry at millimeter-wave frequencies has the ability of topography measurement of different types of terrain, such as water surfaces and tree canopies. A Ka-band interferometric radar was mounted on an airborne platform, and flown over the Connecticut river region in western Massachusetts near Amherst on June 11, 2012. More than 20 Gigabytes of raw data was recorded. This dissertation outline presents the results of the data processing, which includes (1) the estimation and removal of the embedded high frequency phase error in the raw data; (2) the synthetic aperture processing; (3) the interferometric processing. The digital elevation model (DEM ...


Image Processing And Understanding Based On Graph Similarity Testing: Algorithm Design And Software Development, Jieqi Kang 2017 University of Massachusetts - Amherst

Image Processing And Understanding Based On Graph Similarity Testing: Algorithm Design And Software Development, Jieqi Kang

Doctoral Dissertations

Image processing and understanding is a key task in the human visual system. Among all related topics, content based image retrieval and classification is the most typical and important problem. Successful image retrieval/classification models require an effective fundamental step of image representation and feature extraction. While traditional methods are not capable of capturing all structural information on the image, using graph to represent the image is not only biologically plausible but also has certain advantages.

Graphs have been widely used in image related applications. Traditional graph-based image analysis models include pixel-based graph-cut techniques for image segmentation, low-level and high-level ...


Lip Detection And Adaptive Tracking, Benjamin Wang 2017 California Polytechnic State University – San Luis Obispo

Lip Detection And Adaptive Tracking, Benjamin Wang

Master's Theses and Project Reports

Performance of automatic speech recognition (ASR) systems utilizing only acoustic information degrades significantly in noisy environments such as a car cabins. Incorporating audio and visual information together can improve performance in these situations. This work proposes a lip detection and tracking algorithm to serve as a visual front end to an audio-visual automatic speech recognition (AVASR) system.

Several color spaces are examined that are effective for segmenting lips from skin pixels. These color components and several features are used to characterize lips and to train cascaded lip detectors. Pre- and post-processing techniques are employed to maximize detector accuracy. The trained ...


Stringless Guitar, Kue Z. Yang, Anthony Batey, Dominic Mercorelli, Nathaniel Hawk 2017 University of Akron

Stringless Guitar, Kue Z. Yang, Anthony Batey, Dominic Mercorelli, Nathaniel Hawk

Honors Research Projects

The aim of this project is to improve the design of a typical guitar by designing a digital stringless guitar. Due to the nonlinearities inherent in a guitar, it would be difficult to reproduce guitar tones by summing harmonic components; therefore, digital samples of guitar tones were taken in order to preserve these unique and wonderfully sounding tones. These digital samples were stored in the guitar and used to produce its tones when played. The digital guitar includes fingerboard position sensors as well as strum sensors for each string. The fingerboard position sensors detect the player’s fingers at discrete ...


Upper-Bounding The Regularization Constant For Convex Sparse Signal Reconstruction, Renliang Gu, Aleksandar Dogandžić 2017 Iowa State University

Upper-Bounding The Regularization Constant For Convex Sparse Signal Reconstruction, Renliang Gu, Aleksandar Dogandžić

Electrical and Computer Engineering Publications

Consider reconstructing a signal x by minimizing a weighted sum of a convex differentiable negative log-likelihood (NLL) (data-fidelity) term and a convex regularization term that imposes a convex-set constraint on x and enforces its sparsity using ℓ1-norm analysis regularization. We compute upper bounds on the regularization tuning constant beyond which the regularization term overwhelmingly dominates the NLL term so that the set of minimum points of the objective function does not change. Necessary and sufficient conditions for irrelevance of sparse signal regularization and a condition for the existence of finite upper bounds are established. We formulate an optimization problem for ...


An Acoustic-Based Approach For Condition Monitoring Of Pipes, Muhammad S. Khan, Turaj Ashuri, Mitchell Collins, Geoffrey Birkemeier, Emad Almohmmedali 2017 Arkansas Tech University

An Acoustic-Based Approach For Condition Monitoring Of Pipes, Muhammad S. Khan, Turaj Ashuri, Mitchell Collins, Geoffrey Birkemeier, Emad Almohmmedali

Journal of the Arkansas Academy of Science

Polyvinyl chloride pipes are extensively used in municipal sewer systems. As the sewer system ages, polyvinyl chloride pipes become prone to developing cracks that can release toxic effluents into the environment. Traditionally, utility operators pass a close circuit television camera mounted on a guided vehicle through the pipe to monitor the defects. The video is observed by a trained operator who records the condition of the pipe. This arrangement has two major limitations. First, it is expensive due to complex set up. Second, if a pipe is blocked the guided vehicle cannot pass through its entire length. A more economical ...


Time Domain Sar Processing With Gpus For Airborne Platforms, Dustin Lagoy 2017 University of Massachusetts Amherst

Time Domain Sar Processing With Gpus For Airborne Platforms, Dustin Lagoy

Masters Theses

A time-domain backprojection processor for airborne synthetic aperture radar (SAR) has been developed at the University of Massachusetts’ Microwave Remote Sensing Lab (MIRSL). The aim of this work is to produce a SAR processor capable of addressing the motion compensation issues faced by frequency-domain processing algorithms, in order to create well focused SAR imagery suitable for interferometry. The time-domain backprojection algorithm inherently compensates for non-linear platform motion, dependent on the availability of accurate measurements of the motion. The implementation must manage the relatively high computational burden of the backprojection algorithm, which is done using modern graphics processing units (GPUs), programmed ...


Kasi: A Ka-Band And S-Band Cross-Track Interferometer, Gerard Ruiz Carregal 2017 University of Massachusetts Amherst

Kasi: A Ka-Band And S-Band Cross-Track Interferometer, Gerard Ruiz Carregal

Masters Theses

A dual-frequency system is needed to better understand natural processes that constitute the environment and seasonal cycles of the Earth. A system working at two different wavelengths acquiring data simultaneously will give a valuable dataset since the conditions on the ground will be exactly the same. Hence, elements such as wind, soil moisture or any other changes on the ground will not interfere in the mea- surements. This thesis explains how an S-band radar was built and tested. Moreover, the experiments done with a Ka-band radar used as a scatterometer are explained as well as the data processing and analysis ...


Performance Simulation And Optimization Of A Simultaneous Transmit And Receive Phased Antenna Array Using Adaptive Beamforming And Genetic Algorithm Techniques, Ian Thomas Cummings 2017 Michigan Technological University

Performance Simulation And Optimization Of A Simultaneous Transmit And Receive Phased Antenna Array Using Adaptive Beamforming And Genetic Algorithm Techniques, Ian Thomas Cummings

Dissertations, Master's Theses and Master's Reports

The development of simultaneous transmit and receive capabilities is on the cutting-edge of research in phased array technology [1, 2, 3]. The large disparity in power between the transmitted and received signals in antenna systems has traditionally prevented operation in a simultaneous mode. However, simultaneous transmit and receive offers great opportunities for increased capabilities and performance in communications, radar, and electronic warfare applications [3]. This technology will be made feasible by realizing a high level of isolation between the transmitted and received signals through a variety of techniques. This work explores the feasibility of choosing non-standard array partitions that--when paired ...


Constant False Alarm Rate Performance Of Sound Source Detection With Time Delay Of Arrival Algorithm, Xipeng Wang 2017 University of Kentucky

Constant False Alarm Rate Performance Of Sound Source Detection With Time Delay Of Arrival Algorithm, Xipeng Wang

Theses and Dissertations--Electrical and Computer Engineering

Time Delay of Arrival (TDOA) based algorithms and Steered Response Power (SRP) based algorithms are two most commonly used methods for sound source detection and localization. SRP is more robust under high reverberation and multi-target conditions, while TDOA is less computationally intensive. This thesis introduces a modified TDOA algorithm, TDOA delay table search (TDOA-DTS), that has more stable performance than the original TDOA, and requires only 4% of the SRP computation load for a 3-dimensional space of a typical room. A 2-step adaptive thresholding procedure based on a Weibull noise peak distributions for the cross-correlations and a binomial distribution for ...


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