Engineering Commons^™

Automated Robotic Light Bulb Testing Platform, Agha I. Akram, Muhammad Ali Ummy

Publications and Research

The main purpose of this project is to create a functional prototype of a multilayered system that incorporates aspects of electrical, mechanical, and computer engineering technology. The main objective of the system is to be able to determine whether a light bulb is working or not. The building blocks of this system are a robotic arm that is able to slide along a rail (for added mobility), a conveyor belt, and an electromechanical device that holds and tests light bulbs. Initially, the robot arm picks up a light bulb and places it into the holder which then tests it. A …

Electromechanical Fatigue Properties Of Dielectric Elastomer Stretch Sensors Under Orthopaedic Loading Conditions, Andrea Karen Persons

Theses and Dissertations

Fatigue testing of stretch sensors often focuses on high amplitude, low-cycle fatigue (LCF) behavior; however, when used for orthopaedic, athletic, or ergonomic assessments, stretch sensors are subjected to low amplitude, high-cycle fatigue (HCF) conditions. As an added layer of complexity, the fatigue testing of stretch sensors is not only focused on the life of the material comprising the sensor, but also on the reliability of the signal produced during the extension and relaxation of the sensor. Research into the development of a smart sock that can be used to measure the range of motion (ROM) of the ankle joint during …

Memristors, Memcapacitors And Their Application In Neuromorphic Computing, Nithyakalyani Sampath

Student Research Symposium

Data-intensive computing operations, such as training neural networks, are essential but energy-intensive. Memcapacitance and memristance,which can be described as capacitance and resistance, with “memory”, are properties of semiconductor devices that are observed on the nano-scale. These properties allow for data storage without a constant source of power, leading to hardware which is more energy efficient.

We intend to demonstrate that we can build specialized hardware onto which a neural network can be directly mapped using memristors and memcapacitors, improving the energy efficiency of the network. We will use Simulation Program with Integrated Circuit Emphasis (SPICE) to model our memcapacitor and …

Growing Reservoir Networks Using The Genetic Algorithm Deep Hyperneat, Nancy L. Mackenzie

Student Research Symposium

Typical Artificial Neural Networks (ANNs) have static architectures. The number of nodes and their organization must be chosen and tuned for each task. Choosing these values, or hyperparameters, is a bit of a guessing game, and optimizing must be repeated for each task. If the model is larger than necessary, this leads to more training time and computational cost. The goal of this project is to evolve networks that grow according to the task at hand. By gradually increasing the size and complexity of the network to the extent that the task requires, we will build networks that are more …

Probing Myosin Ensemble Mechanics In Actin Filament Bundles Using Optical Tweezers, Omayma Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann

Faculty and Student Publications

Myosins are motor proteins that hydrolyze ATP to step along actin filament (AF) tracks and are essential in cellular processes such as motility and muscle contraction. To understand their force-generating mechanisms, myosin II has been investigated both at the single-molecule (SM) level and as teams of motors in vitro using biophysical methods such as optical trapping. These studies showed that myosin force-generating behavior can differ greatly when moving from the single-molecule level in a three-bead arrangement to groups of motors working together on a rigid bead or coverslip surface in a gliding arrangement. However, these assay constructions do not permit …

Hinged Temperature-Immune Self-Referencing Fabry–Pérot Cavity Sensors, Jeremiah C. Williams, Hengky Chandrahalim

AFIT Patents

A passive microscopic Fabry-Pérot Interferometer (FPI) sensor includes a three-dimensional microscopic optical structure formed on a cleaved tip of the optical fighter using a two-photon polymerization process on a photosensitive polymer by a three-dimensional micromachining device. The three-dimensional microscopic optical structure having a hinged optical layer pivotally connected to a distal portion of a suspended structure. A reflective layer is deposited on a mirror surface of the hinged optical layer while in an open position. The hinged optical layer is subsequently positioned in the closed position to align the mirror surface to at least partially reflect a light signal back …

A Dual-Band Filtering Structure For Highly Selective Reconfigurable Bandpass Filter And Filtering Balun, Jinqun Ge, Guoan Wang

Faculty Publications

This article proposes a filtering structure consisting of two half-wavelength resonators and two open-stub loaded resonators, which generates two third-order passbands. Multiple transmission zeros are introduced by the newly developed coupling scheme, resulting in extremely sharp roll-off desirable for highly selective filters. The proposed structure is applied to design a PIN-diodes switch-controlled reconfigurable dual-band bandpass filter (BPF) with four-state filtering responses: both passbands ON, both passbands OFF, high-frequency passband ON, and low-frequency passband ON. Stepped-impedance open stubs and one-end-grounded coupled lines are studied and employed in the design to suppress unwanted responses. In addition, two filtering structures are placed symmetrically …

Globule Masks-Exact.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley

Deep Learning-based Dot and Globule Segmentation with Pixel and Blob-based Metrics for Evaluation – Data

No abstract provided.

Globule Masks-Dilatedellipsekernel3.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley

Deep Learning-based Dot and Globule Segmentation with Pixel and Blob-based Metrics for Evaluation – Data

No abstract provided.

Images.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley

Deep Learning-based Dot and Globule Segmentation with Pixel and Blob-based Metrics for Evaluation – Data

No abstract provided.

Design Of A Bandgap Voltage Reference, Nicolaus Vail

Electrical Engineering Undergraduate Honors Theses

This thesis details the design process of a bandgap voltage reference (BGR) integrated circuit in a 180 nm CMOS process. A BGR provides a constant DC voltage across a range of operating temperatures and supply voltages. By its nature, the circuit is intended as a reference, not to provide current, so the output would be connected to a very high impedance, such as the gate of a transistor. At 27°C, this design provides a 955 mV reference voltage given a nominal VDD of 3 V. From 20°C to 175°C, the output voltage has a variance of 7.2 mV (approximately 0.8%) …

Signal Analysis Of Photovoltaic Systems For Multilevel Cybersecurity, Wesley G. Schwartz

Electrical Engineering Undergraduate Honors Theses

The cybersecurity of grid-connected power electronics is a rapidly developing field as more and more of these devices become a part of the Internet of Things. The objective of this thesis to analyze the current control signals of a photovoltaic (PV) inverter and develop an interface board for the implementation of a new cyber-secure controller.

In this thesis, the testing and in-depth analysis of the current PV inverter control system will be conducted. Using the data collected, an interface board will be developed to allow the use of the Unified Control Board (UCB), developed by Chris Farnell, in the PV …

Verification And Validation Of Power Converters For Use In Future Power System Architectures, Alexander Johnston

Electrical Engineering Dissertations - Archive

Electronics are more widely penetrating almost every area of society and as they do, the demand to supply them with regulated power increases considerably. The scale of the electronic power distribution systems needed ranges from those in very small handheld consumer electronic devices all the way up to those needed in large buildings, ships, and cities. The energy supplied within these power distribution systems can come from many different generation sources that operate either individually or simultaneously. When power electronics are controlled properly, simultaneous generation sources can be employed in a way that optimizes them according to the user’s desired …

Experimental Validation Of A Reflective Long Period Grating Design Methodology, Sohel Rana, Nirmala Kandadai, Harish Subbaraman

Electrical and Computer Engineering Faculty Publications and Presentations

In this work, we present an experimental demonstration of our previously published modeling work on reflective long period grating (LPG). To provide the practical realization of the modeling work, we coat a long segment of fiber both in the tail length and the end facet beyond the gratings with silver to invert the transmission mode LPG to reflection mode LPG. We then measure the LPG characteristics in both the transmission and reflection mode and validate our findings from modeling work. We further build temperature and refractive index (RI) sensors and demonstrate temperature sensing from 21 °C to 191 °C with …

Improving Intelligent Transportation Safety And Reliability Through Lowering Costs, Integrating Machine Learning, And Studying Model Sensitivity, Cavender Holt

All Theses

As intelligent transportation becomes increasingly prevalent in the domain of transportation, it is essential to understand the safety, reliability, and performance of these systems. We investigate two primary areas in the problem domain. The first area concerns increasing the feasibility and reducing the cost of deploying pedestrian detection systems to intersections in order to increase safety. By allowing pedestrian detection to be placed in intersections, the data can be better utilized to create systems to prevent accidents from occurring. By employing a dynamic compression scheme for pedestrian detection, we show the reduction of network bandwidth improved by 2.12× over the …

Photonic Crystal Surface Emitting Lasers, Akhil Raj Kumar Kalapala

Electrical Engineering Dissertations - Archive

ABSTRACT: Since the initial proposal in 1999 by Noda et al., photonic crystal surface emitting lasers (PCSELs) have proven to achieve large area, coherent lasing with a narrow, single mode beam. Owing to their unique orthogonal electrical/optical cavity scheme, PCSELs have emerged as one of the most promising platforms for high power diode lasers. The evanescent coupling of the optical mode in the active region with the photonic crystal layer enables large area two dimensional in-plane lasing mode in the photonic crystal cavity due to bandedge effect. Bragg’s multi-order diffraction provides the necessary feedback for the lasing and enhances surface …

Evaluation And Modeling Of Power System Components, Zachary Ryan Bailey

Electrical Engineering Dissertations - Archive

Future power system architectures will rely on a combination of rotating machines, power electronic devices, and energy storage. While it is possible to procure each component separately and conduct studies incorporating these devices into a system, increases in computing power and advanced computer modeling software have expanded the opportunity for research to be conducted on power system architectures without the need for actual hardware. This provides flexibility by allowing the user to design models of individual components that can then be integrated together or effortlessly interchanged depending on the function or testbed design that is being studied. The UTA IDEAL …

Poly Camtracker, Nickolas W. Ogilvie, Shawn W. Thai

Electrical Engineering

With the onset of the post-pandemic virtual classroom world, more and more classes are attempting hybrid-style instruction. To accomplish that, recordings of lectures are widely used, with presentation-sharing & audio recording capability. However, video recordings of lectures, with the ability to see the board, lab equipment, and the professor, are the optimal way to give the virtual students the best experience. Right now, technology is readily available for static camera recordings of lecture halls, but this may not suffice when it comes to larger lecture halls and lab demonstrations, where directed shots of equipment or the whiteboard are needed in …

Speaker Diarization And Identification From Single-Channel Classroom Audio Recording Using Virtual Microphones, Antonio Gomez

Electrical and Computer Engineering ETDs

Speaker identification in noisy audio recordings, specifically those from collaborative learning environments, can be extremely challenging. There is a need to identify individual students talking in small groups from other students talking at the same time. To solve the problem, we assume the use of a single microphone per student group without any access to previous large datasets for training.

This dissertation proposes a method of speaker identification using cross-correlation patterns associated to an array of virtual microphones, centered around the physical microphone. The virtual microphones are simulated by using approximate speaker geometry observed from a video recording. The patterns …

Microfluidic Flow Focusing Platforms For Optofluidic Droplet Laser Development, Chen Zhang

Electrical Engineering Dissertations - Archive

ABSTRACT: Optofluidic droplet lasers have been developed for different applications in biomedical sciences, such as biosensing, cell tracking, tissue imaging, on-chip spectroscopy, and flow cytometry. Utilizing different generation methods, droplet lasers can be categorized as either static droplet lasers or droplet lasers on the flow. Static droplet lasers, which are supported by a surface or levitated by an external force, can be optically probed for an extended period of time, and thus enabling continuous monitoring of the lasing emission. However, static droplet lasers suffer from low-throughput generation, large size distribution, and poor reproducibility. In contrast, droplet lasers on the flow …

Power Allocation And Massive Mimo Channel Modeling For 5g Wireless Communications, Zhangliang Chen

Electrical Engineering Dissertations - Archive

To meet the demand for wireless communication transmission rate to reach a thousand times of the existing system in 2021, the fifth-generation (5G) mobile communication system was developed. Compared with Long-Term Evolution (LTE), the 5G mobile communication needs to be transmitted in wireless breakthrough innovation in technology to achieve the goal of ten times increase in spectrum efficiency and power efficiency. As a time series analysis tool based on vector autoregression, Granger causal analysis originated in the field of econometrics, and its staged generalized transfer entropy (TE) based on conditional co-information in information theory has been widely used in recent …

Surface Flashover Under Various Surface Conditions, Bradley A. Hannum

Electrical Engineering Theses - Archive

Electrical insulators are critical components used in every high voltage application whether it is operated continuously or in a pulsed mode. Bulk dielectric breakdown and surface flashover must be prevented in all use cases, especially those that occur in polluted environments. Though electrical standards have been written as a guide to prevent insulator surface flashover, such as Underwriters Laboratories (UL) 840, they are not directly applicable to applications where size and weight are critical. UL 840 experimental design is vague, does not consider all environments, and is written primarily with the electric power utilities in mind. The research presented here …

Unsupervised Anomaly Detection Via Dual Transformation-Aware Embeddings, Zhipeng Wang, Chunping Hou, Bangbang Ge, Yang Liu, Zhicheng Dong, Zhiqiang Wu

Electrical Engineering Faculty Publications

Unsupervised anomaly detection refers to the discovery of unconventional images that are globally or locally different from the training set. Recently, reconstruction-based anomaly detection methods have made great progress. However, most of the existing methods take reconstructing the original image as the goal of latent feature learning. Due to lack of effective semantic guidance, latent features have intrinsic characteristics which retain redundant details of spatial structure. Such information is too general and cause over-expression problem. To solve this problem, in this paper, dual transformation-aware embeddings are coined which aims to achieve a stable model to learn high-level latent features in …

An Efficient End-To-End Deep Neural Network For Interstitial Lung Disease Recognition And Classification, Masum Shah Junayed, Afsana Ahsan Jeny, Md Baharul Islam, Ikhtiar Ahmed, Afm Shahen Shah

Turkish Journal of Electrical Engineering and Computer Sciences

The automated Interstitial Lung Diseases (ILDs) classification technique is essential for assisting clinicians during the diagnosis process. Detecting and classifying ILDs patterns is a challenging problem. This paper introduces an end-to-end deep convolution neural network (CNN) for classifying ILDs patterns. The proposed model comprises four convolutional layers with different kernel sizes and Rectified Linear Unit (ReLU) activation function, followed by batch normalization and max-pooling with a size equal to the final feature map size well as four dense layers. We used the ADAM optimizer to minimize categorical cross-entropy. A dataset consisting of 21328 image patches of 128 CT scans with …

Software Security Management In Critical Infrastructures: A Systematic Literature Review, Gülsüm Ece Ekşi̇, Bedi̇r Teki̇nerdoğan, Cagatay Catal

Turkish Journal of Electrical Engineering and Computer Sciences

Critical infrastructure (CI) is an integrated set of systems and assets that are essential to ensure the functioning of a nation, including its economy, the public's health and/or safety. Hence, protecting critical infrastructures (CI) is vital because of the potential severe consequences that may emerge at the national level. Many CIs are now controlled by software, and likewise, software is often the major source of many security problems in critical infrastructures. Software security management in CIs has been addressed in the literature and several useful approaches have been provided. Yet, these approaches are fragmented over multiple different studies, often do …

A Comprehensive Survey For Non-Intrusive Load Monitoring, Efe İsa Tezde, Eray Yildiz

Turkish Journal of Electrical Engineering and Computer Sciences

Energy-saving and efficiency are as important as benefiting from new energy sources to supply increasing energy demand globally. Energy demand and resources for energy saving should be managed effectively. Therefore, electrical loads need to be monitored and controlled. Demand-side energy management plays a vital role in achieving this objective. Energy management systems schedule an optimal operation program for these loads by obtaining more accurate and precise residential and commercial loads information. Different intellegent measurement applications and machine learning algorithms have been proposed for the measurement and control of electrical devices/loads used in buildings. Of these, nonintrusive load monitoring (NILM) is …

A Survey On Organizational Choices For Microservice-Based Software Architectures, Hüseyi̇n Ünlü, Burak Bi̇lgi̇n, Onur Demi̇rörs

Turkish Journal of Electrical Engineering and Computer Sciences

During the last decade, the demand for more flexible, responsive, and reliable software applications increased exponentially. The availability of internet infrastructure and new software technologies to respond to this demand led to a new generation of applications. As a result, cloud-based, distributed, independently deployable web applications working together in a microservice-based software architecture style have gained popularity. The style has been a common practice in the industry and successfully utilized by companies. Adopting this style demands software organizations to transform their culture. However, there is a lack of research studies that explores common practices for microservices. Thus, we performed a …

Interval Observer-Based Supervision Of Nonlinear Networked Control Systems, Afef Najjar, Thach Ngoc Dinh, Messaoud Amairi, Tarek Raissi

Turkish Journal of Electrical Engineering and Computer Sciences

Networked control system (NCS) is a multidisciplinary area that attracts increasing attention today. In this paper, we deal with remote supervision of a nonlinear networked control systems class subject to network imperfections. Different from many existing researches that consider only the problem of small and/or constant communication delays, we focus on large and time-varying network delays problem in both measurement and control channels. The proposed method is a set-membership estimation-based predictor approach computing a guaranteed set of admissible state values when the uncertainties (i.e. measurement noises and system disturbances) are considered unknown but bounded with a priori known bounds. The …

Evaluation Of Social Bot Detection Models, Muhammet Buğra Torusdağ, Mücahi̇d Kutlu, Ali̇ Aydin Selçuk

Turkish Journal of Electrical Engineering and Computer Sciences

Social bots are employed to automatically perform online social network activities; thereby, they can also be utilized in spreading misinformation and malware. Therefore, many researchers have focused on the automatic detection of social bots to reduce their negative impact on society. However, it is challenging to evaluate and compare existing studies due to difficulties and limitations in sharing datasets and models. In this study, we conduct a comparative study and evaluate four different bot detection systems in various settings using 20 different public datasets. We show that high-quality datasets covering various social bots are critical for a reliable evaluation of …

Classification And Phenological Staging Of Crops From In Situ Image Sequences By Deep Learning, Uluğ Bayazit, Deni̇z Turgay Altilar, Ni̇lgün Güler Bayazit

Turkish Journal of Electrical Engineering and Computer Sciences

Accurate knowledge of crop type information is not only valuable for verifying the declaration of farmers to obtain subsidy or insurance for the grown crop, but also for generating crop type maps that serve a variety of purposes in land monitoring and policy. On the other hand, accurate knowledge of crop phenological stage can help farm personnel apply fertilization and irrigation regimes on a timely basis. Although deep learning based networks have been applied in the past to classify the type and predict the phenological stage of crops from in situ images of fields, more advanced deep learning based networks, …