University of Pennsylvania
Universidad de La Salle, Bogotá
Cornell University
University of Nebraska - Lincoln
Technological University Dublin
Santa Clara University
California Polytechnic State University, San Luis Obispo
Reliable Outdoor Ai-Based Autonomous Uav Localization And Trajectory Tracking Using Cellular Networks,
2024
American University in Cairo
Reliable Outdoor Ai-Based Autonomous Uav Localization And Trajectory Tracking Using Cellular Networks, Ghada Afifi
Theses and Dissertations
Unmanned aerial vehicles (UAVs) are becoming an integral part of numerous commercial and military applications. In many of these applications, the UAV is required to self-navigate in highly dynamic urban environments. Existing localization and trajectory planning techniques, which rely mainly on the Global Positioning System (GPS), do not provide an effective real-time solution for self-localization and path planning, particularly in dense urban environments. The purpose of this thesis is to study the localization and trajectory planning of UAVs independent of GPS systems or other detectable mobile signals. We propose to utilize the broadcast signals from existing cellular networks to localize …
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 …
Representativeness Evaluation Of Delta-Flux Eddy Covariance Towers For Assessing Greenhouse Gas Emissions From Rice Fields In The Mid-South Region,
2023
University of Arkansas, Fayetteville
Representativeness Evaluation Of Delta-Flux Eddy Covariance Towers For Assessing Greenhouse Gas Emissions From Rice Fields In The Mid-South Region, Katherine Skiles
Biological and Agricultural Engineering Undergraduate Honors Theses
Rice grown in 5 states across the Mid-South (AR, LA, MS, TX, and MO) account for nearly 80% of all domestic U.S. rice production. Methane emissions produced during rice farming and the large seasonal water demand to maintain flooded fields have created a need for alternative irrigation research that can reduce methane emissions and conserve water. Structures called eddy covariance towers (ECTs) can observe methane and other flux responses to changing irrigation styles, and their data is shared across flux tower networks such as Delta-Flux in the Mid-South. The Delta-Flux network is relatively new, and its data-sharing capacity is not …
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 …
Investigating Ph And Other Electrical Properties Of Potassium Salt Solutions,
2023
Edith Cowan University
Investigating Ph And Other Electrical Properties Of Potassium Salt Solutions, Li Shu, Xi Lu, Veeriah Jegatheesan, Leonardo Jegatheesan
Research outputs 2022 to 2026
A recent study of ours reported that pH of common salts varies with concentration at room temperature. It can either increase in case of basic salts or decrease in case of acidic salts. In this study, pH values of four kind of potassium salts were investigated and their pH values increased with salt concentrations. It was reasoned that the concentration of hydrogen ions equalled the concentration of positive charges/protons in a solution, so a relationship between the activity of hydrogen ions and charge activity was developed. Further, the well-established equations for pH with hydrogen-ion activity and electrostatic/cell potential were extended …
Understanding Melt Pool Characteristics In Laser Powder Bed Fusion: An Overview Of Single- And Multi-Track Melt Pools For Process Optimization,
2023
Edith Cowan University
Understanding Melt Pool Characteristics In Laser Powder Bed Fusion: An Overview Of Single- And Multi-Track Melt Pools For Process Optimization, Jincheng Wang, Rui Zhu, Yujing Liu, Laichang Zhang
Research outputs 2022 to 2026
Laser powder bed fusion (LPBF) has made significant progress in producing solid and porous metal parts with complex shapes and geometries. However, LPBF produced parts often have defects (e.g., porosity, residual stress, and incomplete melting) that hinder its large-scale industrial commercialization. The LPBF process involves complex heat transfer and fluid flow, and the melt pool is a critical component of the process. The melt pool stability is a critical factor in determining the microstructure, mechanical properties, and corrosion resistance of LPBF produced metal parts. Furthermore, optimizing process parameters for new materials and designed structures is challenging due to the complexity …
Harnessing The Power Of Metal-Organic Frameworks To Develop Microplastic Fouling Resistant Forward Osmosis Membranes,
2023
Edith Cowan University
Harnessing The Power Of Metal-Organic Frameworks To Develop Microplastic Fouling Resistant Forward Osmosis Membranes, Mitra Golgoli, Javad Farahbakhsh, Abdul H. Asif, Mehdi Khiadani, Amir Razmjou, Michael L. Johns, Masoumeh Zargar
Research outputs 2022 to 2026
With the gradual increase of microplastics (MPs) in water and wastewater streams, it is imperative to investigate their removal using tertiary treatment systems to minimize and preferably prevent their entrance into aquatic environments. Forward osmosis (FO) is a non-pressurized membrane process with potential applications in MPs removal from wastewater. However, efficient application of FO systems relies on developing high-performance FO membranes with low fouling tendency. MPs are proven as emerging foulants in membrane systems, diminishing their performance and lifetime and this highlights the need to consider MP fouling in developing sustainable membranes. The current study focuses on a novel modification …
Multifunctional Organic Monolayer-Based Coatings For Implantable Biosensors And Bioelectronic Devices: Review And Perspectives,
2023
Missouri University of Science and Technology
Multifunctional Organic Monolayer-Based Coatings For Implantable Biosensors And Bioelectronic Devices: Review And Perspectives, Taral Patel, Jie Huang, Katarzyna Krukiewicz
Electrical and Computer Engineering Faculty Research & Creative Works
The Emerging Field of Biosensors and Bioelectronics Seeks to Exploit Biology in Combination with the Recent Advances in Engineering. Even Though Biomedical Implants Can Significantly Improve Quality of Life, Problems Following the Process of Implantation Are Still an Issue. in This Review, We Point Out Organic Monolayer-Based Coatings as a Potential Solution to the Major Limitations of Implantable Biomaterials, Including Limited Biocompatibility, the Risk of Biofouling, Bacterial Colonization, and Stability under in Vivo Conditions. at First, Selected Current and Perspective Biomaterials Are Discussed, with the Focus on their Use as Implantable Biosensors and Biomedical Electrodes. Surface Modification Strategies for Implantable …
Enhancing The Co2 Trapping Capacity Of Saudi Arabian Basalt Via Nanofluid Treatment: Implications For Co2 Geo-Storage,
2023
Edith Cowan University
Enhancing The Co2 Trapping Capacity Of Saudi Arabian Basalt Via Nanofluid Treatment: Implications For Co2 Geo-Storage, Muhammad Ali, Nurudeen Yekeen, Mirhasan Hosseini, Ghazanfer R. Abbasi, Amer Alanazi, Alireza Keshavarz, Thomas Finkbeiner, Hussein Hoteit
Research outputs 2022 to 2026
Mineralization reactions in basaltic formations have gained recent interest as an effective method for CO2 geo-storage in order to mitigate anthropogenic greenhouse gas emissions. The CO2/rock interactions, including interfacial tension and wettability, are crucial factors in determining the CO2 trapping capacity and the feasibility of CO2 geological storage in these formations. The Red Sea geological coast in Saudi Arabia has many basaltic formations, and their wetting characteristics are rarely reported in the literature. Moreover, organic acid contamination is inherent in geo-storage formations and significantly impacts their CO2 geo-storage capacities. Hence, to reverse the organic effect, the influence of various SiO2 …
Molecular Dynamics Simulation Of Interfacial Tension Of The Co2-Ch4-Water And H2-Ch4-Water Systems At The Temperature Of 300 K And 323 K And Pressure Up To 70 Mpa,
2023
Edith Cowan University
Molecular Dynamics Simulation Of Interfacial Tension Of The Co2-Ch4-Water And H2-Ch4-Water Systems At The Temperature Of 300 K And 323 K And Pressure Up To 70 Mpa, Quoc Truc Doan, Alireza Keshavarz, Caetano R. Miranda, Peter Behrenbruch, Stefan Iglauer
Research outputs 2022 to 2026
Subsurface geologic formations such as depleted hydrocarbon reservoirs, deep saline aquifers and shale formations have been considered promising targets for carbon dioxide and hydrogen storage. A solid understanding of the interfacial properties of multiphase systems, including binary (pure gas-water) and ternary (gas mixtures and water), is vital to assess for reliability and storage capacity of the geological formations. However, most previous experimental and simulation studies for interfacial properties have mainly focused on binary systems at low-medium pressure. Only a few experimental and simulation studies investigated the interfacial tension at high pressure (above 20 MPa) for the CO2-CH4 …
Hydrogen, Carbon Dioxide, And Methane Adsorption Potential On Jordanian Organic-Rich Source Rocks: Implications For Underground H2 Storage And Retrieval,
2023
Edith Cowan University
Hydrogen, Carbon Dioxide, And Methane Adsorption Potential On Jordanian Organic-Rich Source Rocks: Implications For Underground H2 Storage And Retrieval, Amer Alanazi, Hussein Rasool Abid, Muhammad Usman, Muhammad Ali, Alireza Keshavarz, Volker Vahrenkamp, Stefan Iglauer, Hussein Hoteit
Research outputs 2022 to 2026
Hydrogen (H2) storage in geological formations offers a potential large-scale solution suitable for an industrial-scale hydrogen economy. However, the presence of organic residuals can significantly influence the H2 storage efficiency, as well as cushion gas performance, such as CO2 and CH4, injected to maintain healthy reservoir pressure. Thus, the H2 storage efficiency and cushion gas selectivity were thoroughly investigated in this work based on H2, CO2, and CH4 adsorption measurements using, for the first time, actual organic-rich carbonate-rich Jordanian source rock samples (TOC = 13 % to 18 …
Utilizing Waste Latex Paint Toward Improving The Performance Of Concrete,
2023
Missouri University of Science and Technology
Utilizing Waste Latex Paint Toward Improving The Performance Of Concrete, Mohamed Leithy, Eslam Gomaa, Ahmed A. Gheni, Mohamed Elgawady
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
In this paper, incorporating the waste latex paint (WLP) into the conventional concrete as a partial replacement of sand to improve its durability was investigated. The fresh and hardened characterizations, in addition to the durability of concrete, were examined. The slump test was used to evaluate the fresh properties, while the hardened properties were evaluated through the volume of voids and absorption rate, in addition to the compressive, splitting tensile, and flexural strengths tests. The durability performance was evaluated by the surface resistivity, bulk electrical resistivity, as well as freeze and thaw resistance tests. The results showed a reduction in …
Design And Analysis Of Content Caching Systems,
2023
University of Massachusetts Amherst
Design And Analysis Of Content Caching Systems, Anirudh Sabnis
Doctoral Dissertations
Caching is a simple yet powerful technique that has had a significant impact on improving the performance of various computer systems. From internet content delivery to CPUs, domain name systems, and database systems, caching has played a pivotal role in making these systems faster and more efficient. The basic idea behind caching is to store frequently accessed data locally, so that future requests for that data can be served more quickly. For example, a Content Delivery Network (CDN) like Akamai deploys thousands of edge caches across the globe, so that end-user requests can be served from a nearby cache, rather …
Additive Manufacturing Of High-Performance Nanolamellar Eutectic High-Entropy Alloys,
2023
University of Massachusetts Amherst
Additive Manufacturing Of High-Performance Nanolamellar Eutectic High-Entropy Alloys, Jie Ren
Doctoral Dissertations
Additive manufacturing, also called three-dimensional (3D) printing, is an emerging technology for printing net-shaped components layer by layer for applications in automotive, aerospace, biomedical and other industries. In addition to the vast design freedom offered by this approach, metal 3D printing via laser powder-bed fusion (L-PBF) involves large temperature gradients and rapid cooling and provides exciting opportunities for producing microstructures and mechanical properties beyond those achievable by conventional processing routes. Although these extreme printing conditions enable microstructural refinement to the nanoscale for achieving high strength. However, high-strength nanostructured alloys by laser additive manufacturing often suffer from limited ductility. Eutectic high-entropy …
Capacity Planning For Heterogeneous Patient Populations In Primary Care And Specialty Networks,
2023
University of Massachusetts Amherst
Capacity Planning For Heterogeneous Patient Populations In Primary Care And Specialty Networks, Prashant Meckoni
Doctoral Dissertations
Access to primary care has a direct impact on morbidity and mortality, and is strongly influenced by indirect waiting time: the delay between the requested and allotted appointment day. Our models describe the heterogeneous appointment seeking patterns of a primary care patient panel using stochastic processes parameterized to reflect the diversity of primary care visit rates in the US. For capacity planning, we estimate the distribution of daily appointments, and show that the distribution variability can be reduced by heuristics that use patient flexibility regarding the day of the appointment. For delays, we demonstrate that in a first-come, first-served system, …
A Digital Twin Framework For Production Planning Optimization: Applications For Make-To-Order Manufacturers,
2023
University of Massachusetts Amherst
A Digital Twin Framework For Production Planning Optimization: Applications For Make-To-Order Manufacturers, Ron Mallach
Doctoral Dissertations
In this dissertation, we develop a Digital Twin framework for manufacturing systems and apply it to various production planning and scheduling problems faced by Make-To-Order (MTO) firms. While this framework can be used to digitally represent a particular manufacturing environment with high fidelity, our focus is in using it to generate realistic settings to test production planning and scheduling algorithms in practice. These algorithms have traditionally been tested by either translating a practical situation into the necessary modeling constructs, without discussion of the assumptions and inaccuracies underlying this translation, or by generating random instances of the modeling constructs, without assessing …
Singular Integration By Interpolation For Integral Equations,
2023
University of Massachusetts Amherst
Singular Integration By Interpolation For Integral Equations, Ioannis Kyriakou
Doctoral Dissertations
Maxwell’s equations and the laws of Electromagnetics (EM) govern a plethora of electrical, optical phenomena with applications on wireless, cellular, communications, medical and computer hardware technologies to name a few. A major contributor to the technological progress in these areas has been due to the development of simulation and design tools that enable engineers and scientists to model, analyze and predict the EM interactions in their systems of interest. At the core of such tools is the field of Computational Electromagnetics (CEM), which studies the solution of Maxwell’s equations with the aid of computers. The advances in these applications technologies, …
Performance Of Geopolymer Mortar Using Developed Dry Geopolymer-Cement By A Combination Of Alkaline Solid Activators,
2023
Faculty of Engineering, Structural Engineering Department, Tanta University,
Performance Of Geopolymer Mortar Using Developed Dry Geopolymer-Cement By A Combination Of Alkaline Solid Activators, Mariam Farouk Ghazy, Metwally Abd-Allah Abd-Elaty, Sara Mohamed Mostafa
Mansoura Engineering Journal
This experimental study investigates the possibility of using a combination of solid activators to produce dry powder geopolymer cement. Fly ash (FA) and/or ground granulated blast furnace slag (GGBS) were employed as precursors. Sodium metasilicate pentahydrate (NSP), calcium hydroxide (CH) and sodium carbonate (NC) were used as alkaline solid activators. Meanwhile, the effect of using a combination of solid activators to prepare one-part geopolymer mortars was studied by using three different curing methods and compared with the traditional corrosive alkali solutions that are used as activators in two-part geopolymer mortar, and also compared with Portland cement (PC) mortar mix. Fresh …
Design Of Stormwater Bmps For Surface And Groundwater Protection Based On Site-Scale Soil Properties: Phase I,
2023
University of Central Florida
Design Of Stormwater Bmps For Surface And Groundwater Protection Based On Site-Scale Soil Properties: Phase I, Kelly Kibler, Lisa Chambers, Melanie Beazley
Florida DOT
Much of Earth’s nutrient cycling takes place in soils. Characteristics of soils control physical, chemical, and biological processes that determine rates of nutrient fluxes, storage, or transformation. As remediation of excess nutrients in stormwater runoff is one function of stormwater Best Management Practices (BMPs), the soil profile constitutes one of the most important factors of BMP design. Variation observed in BMP effectiveness (e.g., why one BMP design works effectively in one place and not another) can often be explained by variations in the soil profile, either through direct means or by a soil’s influence on hydraulics of stormwater flow through …
