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Projected Nesterov’S Proximal-Gradient Algorithm For Sparse Signal Recovery, Renliang Gu, Aleksandar Dogandžić 2017 Iowa State University

Projected Nesterov’S Proximal-Gradient Algorithm For Sparse Signal Recovery, Renliang Gu, Aleksandar Dogandžić

Electrical and Computer Engineering Publications

Abstract: We develop a projected Nesterov's proximal-gradient (PNPG) approach for sparse signal reconstruction that combines adaptive step size with Nesterov's momentum acceleration. The objective function that we wish to minimize is the sum of a convex differentiable data-fidelity (negative log-likelihood (NLL)) term and a convex regularization term. We apply sparse signal regularization where the signal belongs to a closed convex set within the closure of the domain of the NLL; the convex-set constraint facilitates flexible NLL domains and accurate signal recovery. Signal sparsity is imposed using the ℓ1 -norm penalty on the signal's linear transform coefficients ...


Perception Of 3d Symmetrical And Near-Symmetrical Shapes, Vijai Jayadevan, Aaron Michaux, Edward Delp, Zygmunt Pizlo 2017 Purdue University

Perception Of 3d Symmetrical And Near-Symmetrical Shapes, Vijai Jayadevan, Aaron Michaux, Edward Delp, Zygmunt Pizlo

MODVIS Workshop

No abstract provided.


Color Algebras, Jeffrey B. Mulligan 2017 NASA Ames Research Center

Color Algebras, Jeffrey B. Mulligan

MODVIS Workshop

No abstract provided.


Implementation Of Range Autofocus For Sar Radar Imaging, Nicholas J. Testin, Philip Davis 2017 Kennesaw State University

Implementation Of Range Autofocus For Sar Radar Imaging, Nicholas J. Testin, Philip Davis

Honors College Capstones and Theses

The range calculation for an FMCW radar depends on accurate linear modulation. In some circumstances, linear modulation may not be available and must be corrected for. This paper describes an autofocus technique used to correct for phase error due to non-linearities in the components of a FMCW radar. Also described here is the algorithm used in calculating the phase error and application of the phase correction with triangle modulation. Known errors were calculated at certain distances and applied to correcting the phase of data taken at similar distances. The results given were generated using a SAR working outside linear ranges.


5g-Ucda Multi Antenna-To-Logical Cell Circular Fifo Mapping Strategy For High-Speed Train Wireless Communications, Subharthi Banerjee 2017 University of Nebraska-Lincoln

5g-Ucda Multi Antenna-To-Logical Cell Circular Fifo Mapping Strategy For High-Speed Train Wireless Communications, Subharthi Banerjee

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

2020 is the target year for the roll out of fifth generation wireless communication methodologies. The commercial vendors have characterized 5G as a collection of disruptive set of technologies to provide high throughput, low latency communication supporting a variety of services, i.e., machine to machine communication to next generation base stations and vehicle-to-vehicle communication to radio-over-fiber and high mobility channels. High-speed train wireless communication channels as a subset of high mobility channels have their clear advantages and disadvantages considering other vehicular channels. The speed of high-speed trains is going to reach 500km/hr and with Hyperloop it may reach ...


Basic Science To Clinical Research: Segmentation Of Ultrasound And Modelling In Clinical Informatics, Ali K. Hamou 2017 The University of Western Ontario

Basic Science To Clinical Research: Segmentation Of Ultrasound And Modelling In Clinical Informatics, Ali K. Hamou

Electronic Thesis and Dissertation Repository

The world of basic science is a world of minutia; it boils down to improving even a fraction of a percent over the baseline standard. It is a domain of peer reviewed fractions of seconds and the world of squeezing every last ounce of efficiency from a processor, a storage medium, or an algorithm. The field of health data is based on extracting knowledge from segments of data that may improve some clinical process or practice guideline to improve the time and quality of care. Clinical informatics and knowledge translation provide this information in order to reveal insights to the ...


Unmanned Aerial Vehicle Tracking System With Out-Of-Sequence Measurement In A Discrete Time-Delayed Extended Kalman Filter, Roque Lora 2017 Utah State University

Unmanned Aerial Vehicle Tracking System With Out-Of-Sequence Measurement In A Discrete Time-Delayed Extended Kalman Filter, Roque Lora

All Graduate Theses and Dissertations

The goal of this thesis is to extend the delayed Kalman filter so it can be used with non-linear systems and that it can handle randomized delays on the measurements. In the particular case of this study, the filter is used to estimates the states of an unmanned aerial system. The outputs of the filter are used to point an antenna and a camera towards a UAS. Different scenarios are simulated for the purpose of comparing the efficiency of this technique in various situations.


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.


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 May 2014 - current

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 ...


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 May 2014 - current

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 ...


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 May 2014 - current

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 ...


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 ...


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 ...


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 May 2014 - current

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 May 2014 - current

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 ...


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 ...


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 ...


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 ...


Sensor Characterization And Signal Fusion For Instanteye, Wyman T. Smith 2017 University of New Hampshire, Durham

Sensor Characterization And Signal Fusion For Instanteye, Wyman T. Smith

Honors Theses and Capstones

The practicality and effectiveness of using a TerraRanger Duo—a parallel sonar and infrared time-of-flight distance sensor—payload for obstacle detection is investigated for use with Physical Science Inc.’s InstantEye drone. A Python program was developed to interface with the serial data output before comparing the sensor’s empirical performance against its data sheet. The two signals from the distinct sensor modules, each with their characterized strengths and weaknesses, were then fused with a Kalman filter. This was further refined by imposing conditional weighting based on the known sensor characteristics. The filter output, with conditional corrections, was able to ...


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