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Signal Processing Commons

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2023

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Articles 31 - 60 of 85

Full-Text Articles in Signal Processing

Visual Question Answering: A Survey, Gehad Assem El-Naggar Jul 2023

Visual Question Answering: A Survey, Gehad Assem El-Naggar

Future Computing and Informatics Journal

Visual Question Answering (VQA) has been an emerging field in computer vision and natural language processing that aims to enable machines to understand the content of images and answer natural language questions about them. Recently, there has been increasing interest in integrating Semantic Web technologies into VQA systems to enhance their performance and scalability. In this context, knowledge graphs, which represent structured knowledge in the form of entities and their relationships, have shown great potential in providing rich semantic information for VQA. This paper provides an abstract overview of the state-of-the-art research on VQA using Semantic Web technologies, including knowledge …


List Of 121 Papers Citing One Or More Skin Lesion Image Datasets, Neda Alipour Jul 2023

List Of 121 Papers Citing One Or More Skin Lesion Image Datasets, Neda Alipour

Other resources

No abstract provided.


Characterization And Estimation Of Musculoskeletal Pain Using Machine Learning, Boluwatife Faremi Jul 2023

Characterization And Estimation Of Musculoskeletal Pain Using Machine Learning, Boluwatife Faremi

Master's Theses

Traditional scales utilized for recording pain are known to be highly subjective and biased due to inaccuracies in recollecting actual pain intensities. As a result, machine learning (ML) models that are trained using these scores as ground truth are reported to have low performance for objective pain classification because of the huge disparity between what was felt in moments of pain and the scores recorded afterward.

In the present study, two devices were designed for gathering real-time, continuous in-session subjective pain scores and the recording of the autonomic nervous system (ANS) altered endodermal (EDA) activity. 24 participants were recruited to …


Optimal Estimation Inversion Of Ionospheric Electron Density From Gnss-Pod Limb Measurements: Part I-Algorithm And Morphology, Dong L. Wu, Nimalan Swarnalingam, Cornelius C. J. H. Salinas, Daniel J. Emmons, Tyler C. Summers, Robert Gardiner-Garden Jun 2023

Optimal Estimation Inversion Of Ionospheric Electron Density From Gnss-Pod Limb Measurements: Part I-Algorithm And Morphology, Dong L. Wu, Nimalan Swarnalingam, Cornelius C. J. H. Salinas, Daniel J. Emmons, Tyler C. Summers, Robert Gardiner-Garden

Faculty Publications

GNSS-LEO radio links from Precise Orbital Determination (POD) and Radio Occultation (RO) antennas have been used increasingly in characterizing the global 3D distribution and variability of ionospheric electron density (Ne). In this study, we developed an optimal estimation (OE) method to retrieve Ne profiles from the slant total electron content (hTEC) measurements acquired by the GNSS-POD links at negative elevation angles (ε < 0°). Although both OE and onion-peeling (OP) methods use the Abel weighting function in the Ne inversion, they are significantly different in terms of performance in the lower ionosphere. The new OE results can overcome the large Ne oscillations, sometimes negative values, seen in the OP retrievals in the E-region ionosphere. In the companion paper in this Special Issue, the HmF2 and NmF2 from the OE retrieval are validated against ground-based ionosondes and radar observations, showing generally good agreements in NmF2 from all sites. Nighttime hmF2 measurements tend to agree better than the daytime when the ionosonde heights tend to be slightly lower. The OE algorithm has been applied to all GNSS-POD data acquired from the COSMIC-1 (2006–2019), COSMIC-2 (2019–present), and Spire (2019–present) constellations, showing a consistent ionospheric Ne morphology. The unprecedented spatiotemporal sampling of the ionosphere from these constellations now allows a detailed analysis of the frequency–wavenumber spectra for the Ne variability at different heights. In the lower ionosphere (~150 km), we found significant spectral power in DE1, DW6, DW4, SW5, and SE4 wave components, in addition to well-known DW1, SW2, and DE3 waves. In the upper ionosphere (~450 km), additional wave components are still present, including DE4, DW4, DW6, SE4, and SW4. The co-existence of eastward- and westward-propagating wave4 components implies the presence of a stationary wave4 (SPW4), as suggested by other earlier studies. Further improvements to the OE method are proposed, including a tomographic inversion technique that leverages the asymmetric sampling about the tangent point associated with GNSS-LEO links.


Real-Time Filters, Spencer Smith Jun 2023

Real-Time Filters, Spencer Smith

Thinking Matters Symposium

This project's goal is to create a visual representation of digital signal processing using a Raspberry Pi Pico board. External components will interface with the Pico to supply digital signals and display the results after processing the signal. A microphone will supply the signal to the Pico which will perform a Fourier Transform on the data and output a spectrogram to a display. The display is named ILI9341 which includes an SPI interface, micro SD card slot, and a 2.2 inch screen. The spectrogram includes the magnitudes of the transformed signal at each frequency and time. Each magnitude is illustrated …


Range-Doppler Map Processing Chain For Marine Radar On Fpga Of An Rfsoc, Nickolas W. Ogilvie Jun 2023

Range-Doppler Map Processing Chain For Marine Radar On Fpga Of An Rfsoc, Nickolas W. Ogilvie

Master's Theses

To improve the accuracy and resolution of the measurements, radar systems employ increasingly complex, resource-intensive signal processing, larger bandwidths, and higher carrier frequencies. However, implementing these improvements requires more expensive, complex electronics that are larger and use more power. Using RFSoC (Radio Frequency System on Chips) in radars can address these challenges. By combining processors, an FPGA (Field Programmable Gate Array), and RF data converters into a single integrated circuit, RFSoCs allow for radar electronics that are physically smaller, use less power, and are simpler to design. As using RFSoCs to perform RF data conversion for radars has been already …


Audio Research Codec, Charlie Sutro Jun 2023

Audio Research Codec, Charlie Sutro

Electrical Engineering

Active Noise and Vibration Control (ANVC) systems are of increasing relevance as urban areas get more densely populated with people and their noise sources. Community noise is of great importance to many forms of transit that aim to bring mobility to a region with minimal subsequent noise pollution. Active Vibration Control (AVC) is an emerging field of research which can be employed to further mitigated unwanted harshness in an acoustic environment by extending the principals of Active Noise Control (ANC)to solid mediums using surface transducers and piezoelectric actuators.

The Audio Research Codec (ARC) is a compact, cost-effective system designed for …


Automotive Collision Warning System Retrofit, Ethan Clark Najmy Jun 2023

Automotive Collision Warning System Retrofit, Ethan Clark Najmy

Electrical Engineering

In the early 2000s, few automakers began implementing forward collision warning systems in their cars. As technology advanced this system became available on more and more luxury cars. In recent years, this technology has spread to more affordable vehicles driven every day. However, as this technology has only recently advanced to less expensive, more economical cars, older vehicles of the same model may not have this advanced and important safety feature. This project investigates and creates a preliminary design for an affordable, easy-to-install, forward collision warning system that can be retrofitted to vehicles without the system currently installed. Using a …


Instrumented Control Column For Optionally Piloted Aircraft, Andrew J. Klein Jun 2023

Instrumented Control Column For Optionally Piloted Aircraft, Andrew J. Klein

Electrical Engineering

Natilus, an aerospace company that is rapid-prototyping optionally piloted aircraft (OPA) for the shipping industry, needs a system that retrieves control column position data in order to manipulate flight simulator parameters in software. At present, a universally compatible system for all aircraft does not exist. Typically, established aerospace companies will sink significant time and money into developing proprietary systems for control column data retrieval as every aircraft is unique in its layout and linkage design. However, as a startup developing their first aircraft, Natilus does not have the privilege of modifying an existing sensor system to work with their HIL …


Sky Survey Radio Telescope, Jack E. Mcguigan Jun 2023

Sky Survey Radio Telescope, Jack E. Mcguigan

Electrical Engineering

This document outlines the design of a radio telescope designed to perform hydrogen line sky surveys. The telescope produces radio images mapping the intensity and relative velocities of hydrogen concentrations to their sky coordinates. Over the course of a day, the telescope images the regions of space visible to it, allowing sky survey imagery to be updated daily. Sky survey images are comprised of an array of pixels corresponding to specific sky coordinates. Each 8-bit RGB pixel contains information on the concentrations of hydrogen in the brightness and relative velocity in the color. Radio images mapping the concentrations and velocities …


Directional Speaker, Gabriel Tramontina Ceribelli, Vincent Trevor Pierce Jun 2023

Directional Speaker, Gabriel Tramontina Ceribelli, Vincent Trevor Pierce

Electrical Engineering

Parametric Acoustic Arrays (PAA) are highly directional soundwaves whose attenuation and spread are much less affected by distance from the source as compared to traditional speakers. A well-known application for PAA is the directional speaker. Studies show that noise directly affects health and decreasing noise pollution can help improve the quality of life for millions of people. Directional speakers can revolutionize society by coupling space with sound. This project encodes audio into two RF-Pulse Width Modulated (PWM) waves to drive a transducer array. Each RF-PWM wave interferes with the other in air to generate a Single Sideband (SSB) frequency spectrum …


Bearing Health Detector, Natalie N. Tokhmakhian, Alexander J. Davis Jun 2023

Bearing Health Detector, Natalie N. Tokhmakhian, Alexander J. Davis

Electrical Engineering

Bearings, a common component in rotating machinery, are essential components of modern rotating machines; thus, monitoring their health is crucial when reducing downtime and boosting production efficiency. The Bearing Health Detector (BHD), a hand-held device, captures and processes the sound of a machine under test in real time and estimates the level of wear and tear by comparing the sound to previous tests. The BHD encompasses audiences involved with roller bearings in rotating machinery and is designed to provide the diagnosis of wear through the universal detection of good, satisfactory, and very poor with the following color scheme: green, yellow, …


Multi-Effects Analog Guitar Pedal, Carson J. Bryan Jun 2023

Multi-Effects Analog Guitar Pedal, Carson J. Bryan

Electrical Engineering

The Multi-FX Analog Guitar Pedal includes the analysis, design, performance, PCB layout, and packaging of an industry-standard effects pedal for an electric guitar. This project takes an analog input signal and utilizes analog circuitry to give the user the option to customize the way that their playing sounds. Effects include the options to add equalization filtering and distortion. The EQ filtering will allow the user to attenuate or gain certain frequencies divided into the 3 standard audio bands: bass (20-300 Hz), middle (300-4000 Hz), and treble (4-20 kHz). The soft-clipping distortion stage will allow the user to move around the …


Practical Podcasting: A Technical Guide To Producing Studio-Quality Podcasts, Jacob Sarmiento Jun 2023

Practical Podcasting: A Technical Guide To Producing Studio-Quality Podcasts, Jacob Sarmiento

Liberal Arts and Engineering Studies

Podcasting exists at the intersection of the technical aspects of audio engineering and disciplines such as journalism and story-telling. Podcasts at KCPR, the student radio station, cover a wide range of topics including the soundscape of the DIY music scene in San Luis Obispo (SLO) on SLO-Fi, the intricacies of navigating SLO on Cal Poly 101, the best of Cal Poly Athletics on The Gallop, and the voices of underrepresented populations on campus on Different Matters. KCPR utilizes podcasts to entertain and inform its audience of the various experiences possible as a Cal Poly student. As a student-run entity, KCPR …


Programmable Vibration Table Retrofit With Eagle Medical, Jonathan Ilagan, Madhav Asok, Max Lewter Jun 2023

Programmable Vibration Table Retrofit With Eagle Medical, Jonathan Ilagan, Madhav Asok, Max Lewter

Biomedical Engineering

This project aimed to repair and upgrade a vibration table used for package testing for the sponsor, Eagle Medical - a medical packaging and sterilization company based in Paso Robles, California. The current vibration table is not programmable and lacks circuit diagrams, making it difficult to repair. In addition, it is not functional due to internal circuitry issues and power requirements. To address these issues, the team will implement several upgrades to improve the product and allow for better random cyclic vibration testing. A full assessment of the existing vibration table will be conducted to ensure the viability of these …


Motion-Resistant Pulse Oximetry, Ludvik Alkhoury May 2023

Motion-Resistant Pulse Oximetry, Ludvik Alkhoury

Dissertations

The measurement of vital signs ? such as peripheral capillary oxygen saturation (SpO2) and heart rate (HR) levels ? by a pulse oximeter is studied. The pulse oximeter is a non-invasive device that measures photoplethysmography (PPG) signals and extracts vital signs from them. However, the quality of the PPG signal measured by oximetry sensors is known to deteriorate in the presence of substantial human and sensor movements contributing to the measurement noise. Methods to suppress such noise from PPG signals measured by an oximeter and to calculate the associated vital signs with high accuracy even when the wearer …


Sparse Methods For Blind Source Separation Of Frequency Hopping Rf Sources, Anushreya Ghosh May 2023

Sparse Methods For Blind Source Separation Of Frequency Hopping Rf Sources, Anushreya Ghosh

Dissertations

Blind source separation (BSS) is performed on frequency hopping (FH) sources. These radio frequency (RF) signals are observed by a uniform linear array (ULA) over a Spatial Channel Model (SCM) in four different propagation environments: (i) line-of-sight (LOS), (ii) single-cluster, (iii) multiple-cluster, and (iv) LOS with interference. The sources are spatially sparse, and their activity is intermittent and assumed to follow a hidden Markov model (HMM). BSS is achieved by utilizing direction of arrival (DOA) of the sources and clusters. A sparse detection framework is applied to obtain estimates of the sources' FH and DOA patterns. The solutions are binned …


Extracting Edges In Space And Time During Visual Fixations, Lynn Schmittwilken, Marianne Maertens May 2023

Extracting Edges In Space And Time During Visual Fixations, Lynn Schmittwilken, Marianne Maertens

MODVIS Workshop

No abstract provided.


Eddy Current Defect Response Analysis Using Sum Of Gaussian Methods, James William Earnest May 2023

Eddy Current Defect Response Analysis Using Sum Of Gaussian Methods, James William Earnest

Theses and Dissertations

This dissertation is a study of methods to automatedly detect and produce approximations of eddy current differential coil defect signatures in terms of a summed collection of Gaussian functions (SoG). Datasets consisting of varying material, defect size, inspection frequency, and coil diameter were investigated. Dimensionally reduced representations of the defect responses were obtained utilizing common existing reduction methods and novel enhancements to them utilizing SoG Representations. Efficacy of the SoG enhanced representations were studied utilizing common Machine Learning (ML) interpretable classifier designs with the SoG representations indicating significant improvement of common analysis metrics.


Approximate And Sample Entropy Of Center Of Pressure In Unperturbed Tandem Standing: Contribution Of Embedding Dimension And Tolerance, Jayla Mashae Wesley May 2023

Approximate And Sample Entropy Of Center Of Pressure In Unperturbed Tandem Standing: Contribution Of Embedding Dimension And Tolerance, Jayla Mashae Wesley

Masters Theses

Approximate entropy (ApEn) and sample entropy (SampEn) are statistical methods designed to quantify the regularity or predictability of a time series. Although ApEn has been a prominent choice for use, it is currently unclear as to which method and parameter selection combination is optimal for its application in biomechanics. The goal of this thesis was to examine the difference between ApEn and SampEn related to center of pressure (COP) data during standing balance tasks, while also refining tolerance r, to determine entropy optimization. Six participants completed five 30-second, feet together and tandem standing, trials under eyes-open and eyes-closed conditions. Ground …


State Estimation And Data Fusion With Data-Driven Communication, Xiaolei Bian May 2023

State Estimation And Data Fusion With Data-Driven Communication, Xiaolei Bian

LSU New Orleans Theses and Dissertations

This dissertation focuses on the systemic design of proper estimation as well as fusion techniques and data-driven communication schemes to infer the state of a dynamic discrete-time linear system over a wireless network. The goal is to effectively extract and share key information over networks to enhance estimates of system states. Such co-design research is drawn by the need to leverage limited resources (communication bandwidth, energy and computational power) for a multitude of data and data sources in networked systems.

We first build the overarching structure by synthesizing communication and estimator/fuser, and research the collective behaviors of the system.

In …


Development Of Medical Device For Volume Status Assessment Using Peripheral Venous Pressure, Audra Beneux May 2023

Development Of Medical Device For Volume Status Assessment Using Peripheral Venous Pressure, Audra Beneux

Graduate Theses and Dissertations

The severe side effects of acute dehydration and blood loss may be prevented if assessed and treated quickly. As amplifier technology has improved, small peripheral venous pressure (PVP) signals collected using a transducer on an intravenous catheter can be analyzed to monitor patient volume status. This thesis details the development of an embedded system prototype that quickly and accurately assesses volume status using PVP analysis. The volume prediction algorithm classified 10 seconds of PVP data as “dehydrated” or “resuscitated”. The hardware design consisted of four primary areas: analog signal conditioning, processing, user interaction, and power. After data collection, the signal …


Power Amplifier Based On Composite Injection-Voltaic Transistors, Nodira Batirdjanovna Alimova Apr 2023

Power Amplifier Based On Composite Injection-Voltaic Transistors, Nodira Batirdjanovna Alimova

Chemical Technology, Control and Management

The problem of high-current radio engineering devices is related to the fact that the use of high-power transistors and other semiconductor devices is limited by such a phenomenon as a secondary breakdown, in which there is a sharp decrease in the voltage on the device with simultaneous internal current lacing, and the device fails. To solve the problem of secondary breakdown, schemes have been proposed that operate stably at reverse voltage values 4-5 times higher than usual and at power dissipation 2-3 times higher than the maximum allowable power for an individual device. The problem is proposed to be solved …


Portable Diffuse Reflectance Spectroscopy For Non-Invasive And Quantitative Assessment Of The Parathyroid Glands Viability During Surgery, Mark Romine, Linh Luong, Alex Moazzen, Katie Cho, Paul Lee Apr 2023

Portable Diffuse Reflectance Spectroscopy For Non-Invasive And Quantitative Assessment Of The Parathyroid Glands Viability During Surgery, Mark Romine, Linh Luong, Alex Moazzen, Katie Cho, Paul Lee

Symposium of Student Scholars

Portable Diffuse Reflectance Spectroscopy for Non-invasive and Quantitative Assessment of the Parathyroid Glands Viability During Surgery

Mark Romine, Linh Luong, Alex Moazzen, Katie Cho and Paul Lee

The parathyroid glands (PTGs) are responsible for the regulation of calcium levels in the blood by secreting a parathyroid hormone. This parathyroid hormone then regulates the body’s absorption, storage, and secretion of calcium, which can directly affect the way muscles and nerves operate. PTGs are often at risk of damage, or accidental removal during thyroid surgeries, because it is challenging to identify PTGs and to determine their viability. Current methods of visual inspections …


Investigating The Use Of Recurrent Neural Networks In Modeling Guitar Distortion Effects, Caleb Koch, Scott Hawley, Andrew Fyfe Apr 2023

Investigating The Use Of Recurrent Neural Networks In Modeling Guitar Distortion Effects, Caleb Koch, Scott Hawley, Andrew Fyfe

[Archive] Belmont University Research Symposium (BURS)

Guitar players have been modifying their guitar tone with audio effects ever since the mid-20th century. Traditionally, these effects have been achieved by passing a guitar signal through a series of electronic circuits which modify the signal to produce the desired audio effect. With advances in computer technology, audio “plugins” have been created to produce audio effects digitally through programming algorithms. More recently, machine learning researchers have been exploring the use of neural networks to replicate and produce audio effects initially created by analog and digital effects units. Recurrent Neural Networks have proven to be exceptional at modeling audio effects …


Chatgpt As Metamorphosis Designer For The Future Of Artificial Intelligence (Ai): A Conceptual Investigation, Amarjit Kumar Singh (Library Assistant), Dr. Pankaj Mathur (Deputy Librarian) Mar 2023

Chatgpt As Metamorphosis Designer For The Future Of Artificial Intelligence (Ai): A Conceptual Investigation, Amarjit Kumar Singh (Library Assistant), Dr. Pankaj Mathur (Deputy Librarian)

Library Philosophy and Practice (e-journal)

Abstract

Purpose: The purpose of this research paper is to explore ChatGPT’s potential as an innovative designer tool for the future development of artificial intelligence. Specifically, this conceptual investigation aims to analyze ChatGPT’s capabilities as a tool for designing and developing near about human intelligent systems for futuristic used and developed in the field of Artificial Intelligence (AI). Also with the helps of this paper, researchers are analyzed the strengths and weaknesses of ChatGPT as a tool, and identify possible areas for improvement in its development and implementation. This investigation focused on the various features and functions of ChatGPT that …


Classification Tradeoffs In Multispectral Polarimetric Ladar Architectures, Connor B. Martin Mar 2023

Classification Tradeoffs In Multispectral Polarimetric Ladar Architectures, Connor B. Martin

Theses and Dissertations

An end-to-end LADAR system is modeled at the waveform level to perform material classification at a per-pixel basis. A K-Nearest Neighbors machine learning algorithm is chosen to make predictions using polarimetric material characteristics as features. A variable receiver design is modeled to allow for the use of multiple configurations of Polarization State Analyzers. This research investigates the inclusion of multiple wavelengths in the transmitted laser pulse to improve classification accuracy. Additionally, the effects of lowering the receiver’s detector bandwidth are investigated. Through the classification process, transmitting a multispectral laser pulse is shown to improve classification and may improve future LADAR …


Effects Of Calibration Errors On Dropped-Channel Polarimetric Synthetic Aperture Radar, Jacob C. Morrison Mar 2023

Effects Of Calibration Errors On Dropped-Channel Polarimetric Synthetic Aperture Radar, Jacob C. Morrison

Theses and Dissertations

Compressed Sensing (CS) is a mathematical technique that can be applied to sparse data sets to allow for sub-Nyquist sampling. DCPCS is a CS technique that recovers the signal from unmeasured polarisation channels due to antenna crosstalk coupling the information onto the remaining channels. DCPCS reduces data storage/transmission and receiver hardware requirements. This thesis examines the robustness of DCPCS to calibration errors on the antenna crosstalk matrix. Although the antenna design problem is relaxed to a large region of acceptable crosstalk values, very accurate calibration may be required in a monostatic radar. This thesis also looks at the importance of …


Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov Feb 2023

Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov

Chemical Technology, Control and Management

In the article given materials of developing of three-phase electromagnetic current transducers of reactive power, using with asynchronous motor, methods connecting of two sensing element, series, parallel and differential and loops suitable for each phase, dynamic characteristics of output signals of three-phase electromagnetic current transducers asynchronous motor.

On the basis of modern calculation and design complexes are of great importance in the research variable sizes of three-phase current electromagnetic transducers of filter-compensation devices of reactive power of asynchronous motors. Presented mathematical model of research of electrical, electromagnetic and magnetic elements of electromagnetic current transducers in the …


On Refinements To Qmfd Based Chirp Parameter Estimation, Balu Santhanam, Thalanayar Santhanam Feb 2023

On Refinements To Qmfd Based Chirp Parameter Estimation, Balu Santhanam, Thalanayar Santhanam

Electrical & Computer Engineering Technical Reports

Commuting matrix methods furnish a full basis of orthog- onal eigenvectors for the discrete Fourier transform or its centered version needed for computing the discrete fractional Fourier transform and multicomponent chirp signal analysis. However, these approaches suffer from ill-conditioning issues at higher matrix sizes, and require a computationally expensive eigenvalue decomposition.

In this paper, ill-conditioning issues associated with the QMFD approach developed previously by the authors are addressed via diagonal modification. Further symmetries of the eigenvectors are used to reduce the size of the underlying eigenvalue problem. These modifications are then incorporated into the real-arithmetic implementation of the QMFD approach …