Electrical and Computer Engineering Commons^™

Spin-Coated High Mobility Moo3 Thin Film For Designing Highly Efficient Lead-Free Perovskite Solar Cells, M. A. Islam, Ihsan Ahmad Siddiquee, Y. A. Wahab, S. F.W. Hatta, Jakaria Mahdi Imam, Foo Wah Low, Aziz Ahamed, Mohammad Nur E. Alam

Research outputs 2022 to 2026

Among the thin film-photovoltaics, perovskite solar cells (PSCs) are one of the most developing topics of research in recent times. Research records reveal that around 26 % efficiency in PSCs has already been achieved so far. However, the commercialization of those PSCs is hindered due to the toxicity of lead (Pb), and the instability of organic cations as well as structural volatility. Several inorganic materials including inorganic hole transport layer (HTL) have recently been proposed and developed to reduce the organic part in the device structure. We fabricate MoO3 thin film materials and conduct a detailed study to realize the …

Strengthening Power Systems For Net Zero: A Review Of The Role Of Synchronous Condensers And Emerging Challenges, Hamid Soleimani, Daryoush Habibi, Mehrdad Ghahramani, Asma Aziz

Research outputs 2022 to 2026

System strength is both supplied and demanded in a power system during normal operations and in the presence of disturbances. This is characterised by stable voltage and frequency, supporting renewable generation such as wind and solar. Because the retirement of synchronous generators reduces system strength supply, and the connection of new inverter-based resource (IBR) generators increases demand, there is an urgent need for new sources of system strength. This paper provides an overview of the challenges brought about by grid modernisation. It highlights tangible solutions provided by synchronous condensers (SCs) to bolster grid strength, stability, and reliability while accommodating the …

Zero Dynamics Attacks On Unknown Bilinear Systems: Vulnerability And Detection, Mohammad Aminul Haq

Electrical & Computer Engineering Theses & Dissertations

Critical infrastructure requires a safe and secure operating environment because of its significant impact on society. Its large-scale size and distributed sensors and actuators make it vulnerable to cyber-physical attacks. A zero dynamics attack is a type of cyber-physical attack where an adversary keeps the output of the target constant (classically zero), while forcing some of the internal states to deviate from their nominal values. Most of the existing work in the literature assumes the system dynamics are linear and available to an adversary. The first goal of this dissertation is to show that an adversary can successfully execute a …

A Kinematic Analysis Of The Shoulder During The Volleyball Attack Using Euler And Helical Axis Methods, Victoria Jolliff

Biomedical Engineering Theses & Dissertations

The shoulder is a complex joint with a wide range of motion, including flexion, extension, abduction, adduction, and internal and external rotation. In volleyball, repetitive overhand movements can cause shoulder overuse injuries. The primary offensive move, the attack, involves the approach, arm cocking, arm acceleration, and follow-through phases. Motion capture analysis and techniques like calculating Euler angles and rotation about a mean helical axis can evaluate shoulder movements. This study aimed to calculate shoulder movements during each phase of the volleyball attack using the Euler angle YXY sequence and the helical axis method. Different attack types, such as cross-court and …

Growth And Simulation Of Dielectric-Metal Nanoheterostructured Thin Films By Ballistic Deposition, Shawn Wimer

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This thesis is divided into two related topics: the structural and chemical characterization of dielectric-metal nanoheterostructured thin films grown by glancing angle deposition (GLAD) and the results of the simulated growth of films and structures by GLAD with discrete-space and continuous-space Monte Carlo ballistic simulation.

Individual structures comprising films grown by GLAD were investigated by S/TEM and SEM imaging, electron diffraction, and chemical characterization and mapping by EDX. Different intermolecular interactions within and between different materials, including Si, Ag, Au, and ZrO₂, are linked to differences in the shapes of individual materials in heterostructures, the shape of heterostructures …

Predicting Iot Distributed Ledger Fraud Transactions With A Lightweight Gan Network, Charles Rawlins, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Decision-making and consensus in traditional blockchain protocols is formulated as a repeated Bernoulli trial that solves a computationally intense lottery puzzle, called Proof-of-Work (PoW) in Bitcoin. This approach has shown robustness through practice but does not scale with increasing network size and generation of new transactions. Resource constrained Internet of Things (IoT) networks are incompatible with full computation of schemes like Bitcoin's PoW. Our effort proposes a first step towards an alternative consensus using machine learning-based decision-making with prediction of fraud transactions to alleviate need for intense computation. To improve base approval probabilities for fraud detection in an ideal security …

Optical Frequency Domain Reflectometry-Based High-Performance Distributed Sensing Empowered By A Data And Physics-Driven Neural Network, Zhaopeng Zhang, Wei Peng, Osamah Alsalman, Lingmei Ma, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Optical frequency domain reflectometry (OFDR) based distributed strain sensors are the preferred choice for achieving accurate strain measurements over extensive sensing ranges while maintaining exceptional spatial resolution. However, the simultaneous realization of high spatial resolution, high strain resolution, large strain range, and an extended sensing range presents an exceedingly challenging endeavor. In this study, we introduce and experimentally demonstrate a data and physics-driven neural network-empowered OFDR system designed to attain high-performance distributed sensing. In our experiments, we successfully maintained an impressive sensing resolution of sub-microstrain (0.91 µε) alongside a sharp spatial resolution of sub-millimeter (0.857 mm) across a 140-m sensing …

Parallel Communications In Single-Core Optical Fibers Utilizing Spatial Domain Multiplexing And Wavelength Division Multiplexing, Mingxuan Tu

Theses and Dissertations

This endeavor proposes a hybrid parallel optical communication architecture in single-core fibers combining WDM in O-band (1270 nm, 1310 nm, 1310 nm, and 1330 nm) and two-channel SDM. The proposed architecture applies carefully designed delays in each propagating channel to achieve synchronization and, therefore, realizes parallel transmission in single-core fibers without the help of Serializer/De-serializers (SerDes). A mathematical model of SDM, calculations on delays between each optical channel, simulation of the hybrid architecture, experimental setup, and the testing and analysis of channel performance have been provided. A design of a photonic integrated circuit based on thin film lithium niobate electro-optic …

Design And Development Of A Direct Medium Voltage Solar Pv Resonant Inverter, Parthkumar Sureshkumar Bhuvela

Theses and Dissertations

In a grid-tied photovoltaic (PV) system connected to a medium voltage (MV) grid, an inverter is generally employed with a line frequency transformer (LFT) to connect to the grid. These LFTs are large in size and weight, exhibit high cost and losses. In recent studies, the LFTs replaced by are by (high frequency transformer) HFT embedded in DC-DC converters. These DC-DC converters are used to boost voltage levels and DC-AC inverters are employed for MV inversion. This leads to high frequency switching at MV which increases losses in inversion stage. In this study, a novel MV grid-connected solar PV inverter …

Increasing Optical Channel Capacity By Integrating Pam4 Modulation With Wavelength Division Multiplexing And Spatial Domain Multiplexing, Swaroopini Harish

Theses and Dissertations

Spatial division multiplexing (SDM) is a technique used in telecommunications and networking to increase data transmission capacity over optical fiber communication channels. This multiplexing technique spatially reuses optical frequencies by allocating different spatial locations for inputs based on their inject angles. The signals travel in a helical pattern within the carrier fiber and exit as concentric rings. SDM enables more efficient utilization of available bandwidth and improved communication performance. In four-level pulse amplitude modulation (PAM4), each symbol represents a combination of four possible signal levels instead of the two levels in binary modulation. The four levels are denoted in different …

Using A Neural Network To Remove Noise From Images, Anvar Asatilloyevich Ravshanov

Chemical Technology, Control and Management

This article proposes modern approaches to the problem of noise reduction in images using neural networks and also analyses the possibilities of noise reduction using neural networks. The convolutional neural network model and the Mediana, Sobel filter were considered for image denoising. The quality improvement of the trained neural network and the comparison with classical noise reduction methods have been carried out.

Ultrasonic Flow Meter Calibration Via The Internet Using An Analog-To-Digital Converter, Aliev Ravshan, A.U. Djalilov

Chemical Technology, Control and Management

The purpose of scientific research work is remote control of improving the metrological properties of the water flow measuring device. Therefore, the Arduino platform with an additional ESP8266 NodeMcu v3 and analog-to-digital converter, module was installed in the scientific article for automatic calibration/checking of ultrasonic flow meters used in irrigation networks. The module is integrated into a 32-bit microcontroller with low power consumption. The ESP8266 NodeMcu v3 module operates at 80 and 160 MHz clock frequencies, supports real-time operating system (RTOS), built-in Wi-Fi, and has a microstrip antenna on board. Through this, the data exchange between the computing equipment and …

Wearable Alcohol Monitoring Device For The Data-Driven Transcutaneous Alcohol Diffusion Model, Ahmed Hasnain Jalal, Sepehr Arbabi, Mohammad A. Ahad, Fahmida Alam, Md. Ashfaq Ahmed

Electrical and Computer Engineering Faculty Publications

Wearable alcohol monitoring devices demand noninvasive, real-time measurement of blood alcohol content (BAC) reliably and continuously. A few commercial devices are available to determine BAC noninvasively by detecting transcutaneous diffused alcohol. However, they suffer from a lack of accuracy and reliability in the determination of BAC in real time due to the complex scenario of the human skin for transcutaneous alcohol diffusion and numerous factors (e.g., skin thickness, kinetics of alcohol, body weight, age, sex, metabolism rate, etc.). In this work, a transcutaneous alcohol diffusion model has been developed from real-time captured data from human wrists to better understand the …

Environmental Monitoring And Control System Of Greenhouse Based On Internet Of Things Technology, Ru Jiang, Nadirbek Yusupbekov

Chemical Technology, Control and Management

Greenhouse is an important application scene of modern agriculture. In this paper, a set of greenhouse environmental monitoring, facility remote control and production management system is designed and implemented based on Internet of Things technology for the development needs of modern agriculture in greenhouse. The system selects STM32F407 control board as the main controller to realize real-time monitoring of greenhouse environmental parameters including temperature and humidity, soil nutrients, soil pH and other greenhouse environmental information, and can adjust greenhouse environmental parameters by controlling the irrigation system, roller shutters, fans, shading curtains and other facilities in the greenhouse. The main controller …

Structural And Parametric Identification Of Recycling Systems, Khusan Igamberdiev, Madina Mirxalilovma Fozilova

Chemical Technology, Control and Management

The issue of identifying recirculation systems with a specific control loop, in which information and control information about various technological processes circulate, is being considered. A methodology for identifying recirculation systems has been developed, based on algorithms for structural identification of the model based on the results of assessing the sensitivity of the optimum of control parameters and a fuzzy inference algorithm based on production rules that contribute to solving the problem of parametric identification.

Research Of The Fuzzy Control System For Adjusting Thread Tension During The Warping Process, To'xtamurod Hayitmurodovich Avezov, Zokhid Ergashboyevich Iskandarov

Chemical Technology, Control and Management

The paper considered issues of research into a fuzzy control system for the warping process. During the warping process, the reasons that cause defects in the final finished product have been studied, firstly (remove this word) which are thread breakage, thread tangling, the formation of loops on or under the belt, hanging loose threads and similar factors. To study the warping process, its mathematical model is constructed. Kinematic parameters of stationary movement corresponding to the equilibrium mode were determined by solving the nonlinear functional matrix - equation of movement. The process of breakage the warp of the threads under oscillation …

Research Of A New Technological Flowsheet Parameters For Uranium Mining From Technogenic Uranium Ores, Nazarov Jamol, G.M. Allaberganova, H.L. Pulatov, A.M. Muzafarov

Chemical Technology, Control and Management

This paper presents the results of a study of the parameters of a new technological scheme for the extraction of uranium from technogenic uranium ores. The results of the analytical determination of the concentration of parent - ²³⁸U and daughter radionuclides - ²³⁴U , ²³⁰Th , ²²⁶Ra , ²²²Rn , ²¹⁸Pa , ²¹⁴Pb , etc. are presented . in the studied technogenic uranium ores. The principal scheme of the new uranium extraction technology from technogenic uranium ores is presented. The use of the classifier in a new scheme for separating granules of technogenic …

Assessment Of Metrological Errors Of Recognition Metrics In The Intelligent Control And Regulation System Of The Cotton Harvesting Machine, Erkin Uljaev, Utkirjon Murodillaevich Ubaydullaev, Azizjon Abdulla Ugli Abdulhamidov

Chemical Technology, Control and Management

This article presents a method for assessing the error of metrics of an intelligent system for monitoring and regulating the width of the working gap of the harvesting apparatus of a cotton picker. To assess the error, the calculation of the average value of the standard deviation of metrics, absolute systematic and random errors, as well as absolute and relative total errors are used. The results of these calculations will allow us to determine the accuracy of the recognition system and opportunities for its improvement.

Control And Management Of The Balance Of Active And Reactive Power In A Power Supply System With A Solar Power Plant, Narzullo Nuriddinovich Mirzoyev, Siroj Sobirovich Nurov

Chemical Technology, Control and Management

This article discusses the development of a measurement and control system for monitoring and managing the balance of active and reactive power at power plants based on “Green” energy sources. Monitoring and management of the balance of active and reactive power based on a measurement and control system, calculated expressions are developed to solve the problem of reactive power compensation when transmitting electricity at power plants based on “green” energy sources. Reactive power is calculated based on measured active power, and combined reactive power sources generate the reactive power required by the network based on control signals. Schemes for connecting …

Decision-Making Algorithms For Drilling Instrument Control Systems, Fuzayl Fozil Ugli Odilov

Chemical Technology, Control and Management

The control of the movement of the drilling tool and the structure of the well are considered. An effective control algorithm for drilling systems that provides control of well trajectory parameters is analyzed. In technological processes, it is necessary to control several parameters or several systems at the same time. It is considered necessary to create decision-making algorithms for the formation of managerial effects for the control system of such technological processes. The controlled oriented type of the bottom of the drill string was analyzed. Work was carried out on the decision-making algorithm for the processing of control effects. The …

Algorithms And Models For Synthesis Of Elements Of Digital Information Systems, Odil Abdujalilovich Jumaev, M.T. Ismoilov, V.B. Pulatov, G.X. Rashidov

Chemical Technology, Control and Management

The development of algorithms for noise-tolerant and high-speed measurement systems involves an integrated approach that encompasses methods of data processing and transmission, as well as mechanisms for rapid response to changes. This paper presents the key principles and techniques used in such technologies. The information systems are thoroughly analyzed, including the use of signal processing techniques and their identification, filtering using various statistical techniques to determine signal parameters and the development of algorithms to analyze and classify signals. Critical aspects of the system such as performance, reliability, security and scalability are also evaluated. The paper discusses information system structures and …

Advancing Influence In Social Networks Based On Game Theory, Adedamola Adesokan

Electrical and Computer Engineering ETDs

Online Social Networks (OSNs) have become part of our everyday life, as a means of interacting with people, sharing content, attending events, etc. Influencers are professional OSN users, who have a large loyal audience and use the OSNs to market various goods or services based on brand partnerships. In this thesis, we introduce a novel mechanism to enable OSN users to become influencers by strategically deciding their activity within the OSN. Initially, the concepts of social coordinates and social communities are proposed. Then, a non-cooperative game is introduced to enable the users to make optimal decisions regarding their activity in …

Matrix Processing With Photonic Analog Computing, James Michael Garofolo

Theses and Dissertations

In the digital age, a wide variety of engineering problems have been solved, to a great deal of success, by digital computing techniques. The flexibility of software and relatively low cost of digital computing hardware make it an ideal starting point for solving a majority of tasks, and the numerical stability of software solutions make it highly appealing as the major workhorse for computational tasks. Despite this, many problems are actually suboptimally solved by digital methods, leading to systems with high latency, low throughput, power hungry parallel processing units and an excess of memory for discretizing sensor inputs. Computational photonic …

Surface Structures And Properties Of High-Voltage Licoo2: Reviews And Prospects, Jian-Jun Fang, Yu-Hao Du, Zi-Jian Li, Wen-Guang Fan, Heng-Yu Ren, Hao-Cong Yi, Qing-He Zhao, Feng Pan

Journal of Electrochemistry

Nowadays, the development of high-voltage LiCoO₂ (lithium cobalt oxide, LCO) cathodes has attracted the widespread attention from both the academic and industry fields. Among the multiple concerns, researches on the surface issues would provide the most effective performance optimization pathway for the synthesis of high-voltage LCO. In this work, the issues of high-voltage LCO, including the phase transitions and crack formation, the oxygen redox related issues and side reactions, as well as the surface structure degradation, have been systematically reviewed. Then, we further clarify the surface modulations, and the interplay between the surface modulation and electrolyte tuning. Finally, we …

In Situ Diffuse Reflectance Spectroelectrochemistry Of Cathode Materials In Lithium-Ion Batteries, Lu-Lu Chen, Hao-Ran Li, Wei-Yi Liu, Wei Wang

Journal of Electrochemistry

Developing in situ spectroelectrochemistry methods, which can provide detailed information about species transformation during electrochemical reactions, is very important for studying electrode reaction mechanisms and improving battery performance. Studying real-time changes in the surface of electrode materials during normal operation can be an effective way to assess and optimize the practical performance of electrode materials, thus, in situ and in operando characterization techniques are particularly important. However, batteries are hard to be studied by in situ characterization measurements due to their hermetically sealed shells, and there is still much room for battery characterizations. In this work, a specially designed battery …

Molybdenum Disulfide And Carbon Nanotubes Composite Electrode For Electrochemical Conversion Of Salinity Gradient Energy, Jia-Jun Li, Wei-Bin Zhang, Xin-Yu Liu, Jing-Lei Yang, Yi Yin, Ze-Qin Yang, Xue-Jing Ma

Journal of Electrochemistry

The ocean accounts for 97% of the total water resources on earth, covering over 70% of the map's surface area. With the continuous consumption of non-renewable energy sources such as fossil fuels and the rapid development of renewable energy, humans are increasingly paying attention to the utilization of ocean resources. Ocean energy includes tidal energy, wave energy, temperature difference energy, and salinity gradient energy. Salinity gradient energy is the energy generated by the interaction of seawater and fresh water, which is the ocean energy existing in the form of chemical energy. This energy is mostly generated in estuaries. The osmotic …

Electronic Properties Of Group-Iii Nitride Semiconductors And Device Structures Probed By Thz Optical Hall, Nerijus Armakavicius, Philipp Kühne, Alexis Papamichail, Hengfang Zhang, Sean Knight, Axel Persson, Vallery Stanishev, Jr-Tai Chen, Plamen Paskov, Mathias Schubert, Vanya Darakchieva

Department of Electrical and Computer Engineering: Faculty Publications

Group-III nitrides have transformed solid-state lighting and are strategically positioned to revolutionize high-power and high-frequency electronics. To drive this development forward, a deep understanding of fundamental material properties, such as charge carrier behavior, is essential and can also unveil new and unforeseen applications. This underscores the necessity for novel characterization tools to study group-III nitride materials and devices. The optical Hall effect (OHE) emerges as a contactless method for exploring the transport and electronic properties of semiconductor materials, simultaneously offering insights into their dielectric function. This nondestructive technique employs spectroscopic ellipsometry at long wavelengths in the presence of a magnetic …

Deep Learning Framework For Graph-Based Molecular Drug Discovery, Daniel Manu

Electrical and Computer Engineering ETDs

This dissertation proposes the GraphGANFed framework, which combines Graph Convolutional Networks (GCN), Generative Adversarial Networks (GAN), and Federated Learning (FL) to generate novel molecules while preserving data privacy. FL allows learning from distributed clients without sharing local datasets, GCN extracts molecular structural properties, and GAN generates new molecules retaining the learned properties. Extensive simulations on three benchmark datasets show GraphGANFed's effectiveness, producing molecules with high novelty (≈ 100) and diversity (> 0.9). Results indicate a trade-off among evaluation metrics, and the right dropout ratio avoids mode collapse. Additionally, Conditional GraphGANFed (cGraphGANFed) incorporates a critic network from Reinforcement Learning (RL) to …

Plc Multi-Robot Integration Via Ethernet For Human Operated Quality Sampling, Jeevan S. Devagiri, Paniz Khanmohammadi Hazaveh, Nathir Rawashdeh, Sai Revanth Reddy Dudipala, Pratik Mohan Desmuhk, Aditya Prasad Karmarkar

Michigan Tech Publications

In automation, quality control inspection is a critical requirement to ensure product standards. The goal of this work is to insure product quality without interrupting the production line flow. The multi-robot system presented, connects a programmable logic controller (PLC), as the main controller, to a conveyor belt and two FANUC industrial robotic arms via EtherNet/IP. Human interaction is implemented to pick a work piece from the moving conveyor and return it with a quality label. This label is used by the PLC to execute the correct robot action; either to return the inspected part to the conveyor or discard it …

Creative Insights Into Motion: Enhancing Human Activity Understanding With 3d Data Visualization And Annotation, Isaac Browen, Hector M. Camarillo-Abad, Franceli L. Cibrian, Trudi Di Qi

Engineering Faculty Articles and Research

This paper presents a novel 3D system for human motion analysis - Motion Data Visualization and Annotation (MoViAn). Designed to provide a comprehensive visual representation of 3D human motion data, MoViAn incorporates detailed visualization of gaze direction, hand movements, and object interactions, alongside an interactive interface for efficient data annotation. A user study involving eight participants indicates that MoViAn enables users to thoroughly explore and annotate human motion data, with System Usability Scale (SUS) results demonstrating a satisfactory usability level. The contribution of this paper lies in the development of an interactive and usable data analytics tool aimed at deepening …