External Direct Sum Invariant Subspace And Decomposition Of Coupled Differential-Difference Equations,
2024
Southern Illinois University Edwardsville
External Direct Sum Invariant Subspace And Decomposition Of Coupled Differential-Difference Equations, Keqin Gu, Huan Phan-Van
SIUE Faculty Research, Scholarship, and Creative Activity
This article discusses the invariant subspaces that are restricted to be external direct sums. Some existence conditions are presented that facilitate finding such invariant subspaces. This problem is related to the decomposition of coupled differential-difference equations, leading to the possibility of lowering the dimensions of coupled differential-difference equations. As has been well documented, lowering the dimension of coupled differential-difference equations can drastically reduce the computational time needed in stability analysis when a complete quadratic Lyapunov-Krasovskii functional is used. Most known ad hoc methods of reducing the order are special cases of this formulation.
The Need For Energy Storage On Renewable Energy Generator Outputs To Lessen The Geeth Effect, I.E. Short-Term Variations Mainly Associated With Wind Turbine Active Power Output,
2023
Technological University Dublin
The Need For Energy Storage On Renewable Energy Generator Outputs To Lessen The Geeth Effect, I.E. Short-Term Variations Mainly Associated With Wind Turbine Active Power Output, Tony Kealy
Articles
Many studies investigating the short-term variations associated with the power output from wind turbine generators utilise simulated or modelled data in the analysis. This current study uses short-term empirical data downloaded directly from operational wind turbines via electrical power quality meters. The empirical data shows that the short-term variations (one-second or sub-one-second timeframe) occur continuously over most of the power output range. A novel name is proposed, the Geeth Effect, for this variability phenomenon. The Geeth Effect is measured using the coefficient of variation mathematical expression and is likely contributing to (i) lower-than-expected financial and environmental benefits associated with …
Directional Microwave Emission From Femtosecond-Laser Illuminated Linear Arrays Of Superconducting Rings,
2023
Air Force Research Laboratory
Directional Microwave Emission From Femtosecond-Laser Illuminated Linear Arrays Of Superconducting Rings, Thomas J. Bullard, Kyle Frische, Charlie Ebbing, Stephen J. Hageman, John Morrison, John Bulmer, Enam A. Chowdury, Michael L. Dexter, Timothy J. Haugan, Anil K. Patniak
Faculty Publications
We examine the electromagnetic emission from two photo-illuminated linear arrays composed of inductively charged superconducting ring elements. The arrays are illuminated by an ultrafast infrared laser that triggers microwave broadband emission detected in the 1–26 GHz range. Based on constructive interference from the arrays a narrowing of the forward radiation lobe is observed with increasing element count and frequency demonstrating directed GHz emission. Results suggest that higher frequencies and a larger number of elements are achievable leading to a unique pulsed array emitter concept that can span frequencies from the microwave to the terahertz (THz) regime.
Vertical Free-Swinging Photovoltaic Racking Energy Modeling: A Novel Approach To Agrivoltaics,
2023
Western University
Vertical Free-Swinging Photovoltaic Racking Energy Modeling: A Novel Approach To Agrivoltaics, Koami Soulemane Hayibo, Joshua M. Pearce
Electrical and Computer Engineering Publications
To enable lower-cost building materials, a free-swinging bifacial vertical solar photovoltaic (PV) rack has been proposed, which complies with Canadian building codes and is the lowest capital-cost agrivoltaics rack. The wind force applied to the free-swinging PV, however, causes it to have varying tilt angles depending on the wind speed and direction. No energy performance model accurately describes such a system. To provide a simulation model for the free-swinging PV, where wind speed and direction govern the array tilt angle, this study builds upon the open-source System Advisor Model (SAM) using Python. After the SAM python model is validated, a …
An Improved Genetic Algorithm Based Fractional Open Circuit Voltage Mppt For Solar Pv Systems,
2023
Edith Cowan University
An Improved Genetic Algorithm Based Fractional Open Circuit Voltage Mppt For Solar Pv Systems, Aakash Hassan, Octavian Bass, Mohammad A. S. Masoum
Research outputs 2022 to 2026
To extract the maximum power from solar PV, maximum power point tracking (MPPT) controllers are needed to operate the PV arrays at their maximum power point under varying environmental conditions. Fractional Open Circuit Voltage (FOCV) is a simple, cost-effective, and easy to implement MPPT technique. However, it suffers from the discontinuous power supply and low tracking efficiency. To overcome these drawbacks, a new hybrid MPPT technique based on the Genetic Algorithm (GA) and FOCV is proposed. The proposed technique is based on a single decision variable, reducing the complexity and convergence time of the algorithm. MATLAB/Simulink is used to test …
Gps-Denied Navigation Using Synthetic Aperture Radar,
2023
Utah State University
Gps-Denied Navigation Using Synthetic Aperture Radar, Tucker Hathaway
All Graduate Theses and Dissertations, Fall 2023 to Present
In most modern navigation systems, GPS is used to determine the precise location of the vehicle; however, GPS signals can easily be blocked, jammed, or spoofed. These signals can be blocked by canyons or tall buildings. Additionally, adversaries can transmit signals that either make GPS signals difficult to interpret or that imitate real GPS signals and cause a navigation system to think it is somewhere other than its true location. GPS-denied (GPS-D) navigation is the process of navigating in the absence of GPS.
Many methods of performing GPS-D navigation have been proposed and explored. One such method is to use …
On The Effect Of Emotion Identification From Limited Translated Text Samples Using Computational Intelligence,
2023
Edith Cowan University
On The Effect Of Emotion Identification From Limited Translated Text Samples Using Computational Intelligence, Madiha Tahir, Zahid Halim, Muhmmad Waqas, Shanshan Tu
Research outputs 2022 to 2026
Emotion identification from text data has recently gained focus of the research community. This has multiple utilities in an assortment of domains. Many times, the original text is written in a different language and the end-user translates it to her native language using online utilities. Therefore, this paper presents a framework to detect emotions on translated text data in four different languages. The source language is English, whereas the four target languages include Chinese, French, German, and Spanish. Computational intelligence (CI) techniques are applied to extract features, dimensionality reduction, and classification of data into five basic classes of emotions. Results …
Analog Cancellation Of A Known Remote Interference: Hardware Realization And Analysis,
2023
University of Massachusetts Amherst
Analog Cancellation Of A Known Remote Interference: Hardware Realization And Analysis, James M. Doty
Masters Theses
The onset of quantum computing threatens commonly used schemes for information secrecy across wireless communication channels, particularly key-based data-level encryption. This calls for secrecy schemes that can provide everlasting secrecy resistant to increased computational power of an adversary. One novel physical layer scheme proposes that an intended receiver capable of performing analog cancellation of a known key-based interference would hold a significant advantage in recovering small underlying messages versus an eavesdropper performing cancellation after analog-to-digital conversion. This advantage holds even in the event that an eavesdropper can recover and use the original key in their digital cancellation. Inspired by this …
Refinement And Performance Analysis Of The Stepped Frequency Microwave Radiometer In Extra Tropical Cyclone Conditions,
2023
University of Massachusetts Amherst
Refinement And Performance Analysis Of The Stepped Frequency Microwave Radiometer In Extra Tropical Cyclone Conditions, Jezabel Vilardell Sanchez
Doctoral Dissertations
The Stepped Frequency Microwave Radiometer (SFMR) is a key instrument for estimation of ocean surface wind speed and rain rate in tropical and extra-tropical cyclones research. Through the observed brightness temperature (TB) over a range of six C-band frequencies, the SFMR derives these key parameters used by hurricane specialists to issue watches and warnings. The information gathered with this instru- ment is also pivotal for post-storm studies and satellite calibrations. Currently, the SFMR requires an average time of 5-10 seconds of averaging to cycle through the six di↵erent frequency channels, so in regions with strong wind/rain gradients such as the …
The Automated Wheelchair,
2023
Georgia Southern University
The Automated Wheelchair, Jonathan Doksa Kamba Ngoyi
Honors College Theses
Automation refers to the use of technology to execute tasks through programmed instructions and automated control mechanisms to ensure accurate execution. This minimizes human involvement and encompasses various fields, including business process automation. A notable form of automation is assistive technology, which refers to any device or software that enhances individuals' learning, communication, or overall functionality. This can range from advanced tools like computers to simpler aids like walking sticks. Assistive technology aims to promote inclusivity and participation, particularly among individuals with disabilities, the elderly, and those with non-communicable diseases.
The Automated Airport Wheelchair is a culmination of prior projects …
Survey On Wi-Fi And Cellular Communication Technology For Advanced Metering Infrastructure (Ami) In A Developing Economy,
2023
Engineering Materials Development Institute,Km 4, Akure, Ondo State of Nigeria and Federal University of Technology, Akure, Ondo State, Nigeria.
Survey On Wi-Fi And Cellular Communication Technology For Advanced Metering Infrastructure (Ami) In A Developing Economy, Tejumade F. Anthony, Folasade M. Dahunsi
The African Journal of Information Systems
Traditional energy meters have suffered from a lack of automated analysis and inaccuracy in reading energy consumption, which has brought about smart metering systems. Developing economies such as in Africa. still experience a setback in electricity monitoring and load distribution because of existing traditional meter systems in use. Communication technologies play an important role to improve the monitoring of energy consumption and ensure a road map toward a smart grid. This paper reviews communication technologies used for Advanced Metering Infrastructure (AMI) emphasizing Wi-Fi and Cellular technologies. Metrics used to evaluate their performance include cost, energy efficiency, coverage, deployment, latency, payload, …
Modeling Hydration Kinetics Of Sustainable Cementitious Binders Using An Advanced Nucleation And Growth Approach,
2023
Missouri University of Science and Technology
Modeling Hydration Kinetics Of Sustainable Cementitious Binders Using An Advanced Nucleation And Growth Approach, Taihao Han, Jie Huang, Gaurav Sant, Narayanan Neithalath, Ashutosh Goel, Aditya Kumar
Electrical and Computer Engineering Faculty Research & Creative Works
Supplementary cementitious materials (SCMs) are utilized to partially substitute Portland cement (PC) in binders, reducing carbon-footprint and maintaining excellent performance. Nonetheless, predicting the hydration kinetics of [PC + SCM] binders is challenging for current analytical models due to the extensive diversity of chemical compositions and molecular structures present in both SCMs and PC. This study develops an advanced phase boundary nucleation and growth (pBNG) model to yield a priori predictions of hydration kinetics—i.e., time-resolved exothermic heat release profiles—of [PC + SCM] binders. The advanced pBNG model integrates artificial intelligence as an add-on, enabling it to accurately simulate hydration kinetics for …
Comparative Evaluation Of Investigation Methods For Estimating The Load-Dependent State Of Charge And End Of Discharge Of A Multirotor Uav Battery,
2023
Flensburg University of Applied Sciences
Comparative Evaluation Of Investigation Methods For Estimating The Load-Dependent State Of Charge And End Of Discharge Of A Multirotor Uav Battery, Hanna Dibbern, Morten Roßberg, Claudia Werner
Journal of Aviation Technology and Engineering
As the scope of multirotor unmanned aerial vehicle (UAV) applications increases, more attention is being paid to UAV energy requirements, which vary depending on the mission profile. To obtain accurate information about the UAV battery during flight, the idea of a digital twin including a battery state estimation model is promising. For battery state estimation, a Kalman filter combination is the preferred approach in the literature. Comparing different Kalman filters, the unscented Kalman filter has a more accurate estimation for nonlinear systems compared to the extended Kalman filter. In the application of UAV flight with load-dependent flight missions, the comparison …
Stereoscopic-Based Mass Properties Estimation For Warhead Fragments,
2023
University of Naples Federico II
Stereoscopic-Based Mass Properties Estimation For Warhead Fragments, Alessia Nocerino, Katharine Larsen, Riccardo Bevilacqua, Elisabetta L. Jerome
Student Works
FRAGMENTATION characteristics such as spatial distribution, number of fragments, fragment velocity, and fragment mass can be used to characterize the lethality of a fragmenting weapon or any metal cased explosive [1,2]. However, most warhead tests and evaluations are limited to static arena testing, where fragment characteristics must be collected by hand. Recently, stereoscopic imaging techniques have been added to static arena tests. Using this method, position tracks can be collected for each fragment, and then velocity information can be found. This paper proposes a method to estimate the mass and moment of inertia using data collected by a stereoscopic imaging …
Optimal And Robust Control Problems Of Microalgae Cultivation,
2023
Universidad Autonoma Metropolitana - Azcapotzalco
Optimal And Robust Control Problems Of Microalgae Cultivation, Mariana Rodriguez-Jara, Luis A. Ricardez-Sandoval, Carlos E. Ramirez-Castelan, Hector Puebla
Annual Symposium on Biomathematics and Ecology Education and Research
No abstract provided.
Research Outreach Interdisciplinary Activity To Classify Olive Oil Blends Integrating Multicolor Imaging, Image Processing, And Machine Learning,
2023
The University of Memphis
Research Outreach Interdisciplinary Activity To Classify Olive Oil Blends Integrating Multicolor Imaging, Image Processing, And Machine Learning, Allan Abraham, Kameshwaran Balachandran
Undergraduate Research
This outreach undergraduate research project presents a low-cost method to distinguish the quality of different olive oils. The proposed method is based on an indirect measurement of the chlorophyll molecules present when a green laser diode illuminates the oil sample. Oil blends can be classified into five classes (no olive oil, light olive oil, medium olive oil, olive oil, and extra virgin olive oil) by quantifying the ratio of the red channel versus the green channel along the laser illumination path from a color image. After labeling each oil blend, a convolutional neural network has been implemented and trained to …
Preparation And Electrocatalytic Performance Of Feni-Cop/Nc Bifunctional Catalyst,
2023
Coellece of Transportation Engineering, Dalian Maritime University, Dalian, Liaoning, 361005, China
Preparation And Electrocatalytic Performance Of Feni-Cop/Nc Bifunctional Catalyst, Si-Miao Liu, Jing-Jiao Zhou, Shi-Jun Ji, Zhong-Sheng Wen
Journal of Electrochemistry
Rechargeable zinc-air batteries have gradually attracted much attention worldwide due to their high capacity, high energy density and low price. Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) correspond to the charging and discharging processes in rechargeable zinc-air battery, respectively. At present, commercial Pt/C and IrO2 catalysts hinder the large-scale application of zinc-air batteries due to low reserves, high prices and poor stability. Therefore, exploring high performance, low cost and high stability with dual functional catalysts is important for the development of rechargeable zinc-Air batteries. The metal-organic frameworks (MOFs) have high specific surface area, structural stability, good catalytic …
Charge-Dependence Of Dissolution/Deposition Energy Barrier On Cu(111) Electrode Surface By Multiscale Simulations,
2023
Materials Genome Institute, Shanghai University, 200444 Shanghai, China
Charge-Dependence Of Dissolution/Deposition Energy Barrier On Cu(111) Electrode Surface By Multiscale Simulations, Hang Qiao, Yong Zhu, Sheng Sun, Tong-Yi Zhang
Journal of Electrochemistry
Behaviors of electrified interface under different applied potentials/charges play the central role in electroplating process and electrochemical corrosion. The mechanism, however, is unclear yet for a surface atom dissolving/depositing from/on an electrode surface under an applied potential. The energy barrier along the reaction path is the key variable. The present work conductes hybrid first-principle/hybrid calculations to study the direct and indirect dissolution/deposition of a Cu atom on perfect/stepped Cu(111) planar electrodes in an electrolyte under different excess charges. Energy profiles present a linear relationship between the energies of the initial/final state and the activation state of different reaction paths under …
Research Progress And Performance Improvement Strategies Of Hard Carbon Anode Materials For Sodium-Ion Batteries,
2023
School of Science, Shanghai University, Shanghai 200444, China
Research Progress And Performance Improvement Strategies Of Hard Carbon Anode Materials For Sodium-Ion Batteries, Xiu-Ping Yin, Yu-Feng Zhao, Jiu-Jun Zhang
Journal of Electrochemistry
This paper systematically summarizes the research progress of hard carbon anode materials in sodium ion batteries(SIBs) and the development of the corresponding sodium storage mechanism in recent years, and reviews the performance improvement strategies of hard carbon materials from the aspects of structural design and electrolyte regulation. The effects of the selection of precursors, carbonization temperature, pretreatment, pore formers, heteroatom doping, material compounding, electrolyte regulation and pre-sodiumization on the sodium storage performance of hard carbon anode materials are briefly described. This paper provides new insights into the design, synthesis and electrolyte
matching of high-performance and low-cost hard carbon materials, and …
Surface Modifications Of Lini0.96Co0.02Mn0.02O2 With Tungsten Oxide And Phosphotungstic Acid,
2023
College of Energy, Xiamen University, Xiamen 361005, Fujian, China
Surface Modifications Of Lini0.96Co0.02Mn0.02O2 With Tungsten Oxide And Phosphotungstic Acid, Gang Zhao, Zheng-Liang Gong, Yi-Xiao Li, Yong Yang
Journal of Electrochemistry
With the rapid development of electric vehicles, enormous demands are made for higher energy density, better cycling performance and lower cost of lithium-ion batteries (LIBs). As an important high capacity cathode material for LIBs, the high nickel layered oxide material LiNi0.8Co0.1Mn0.1O2(NCM811) can reach an energy density of 760 Wh·kg–1. The ultra-high nickel ternary positive electrode material (LiNi1-x-yCoxMnyO2, x ≥ 0.90) has a specific capacity of more than 210 mAh·g–1, and can realize higher energy density. Besides, an ultra-high nickel material …
