Engineering Commons^™

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, 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 …

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 …

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 …

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 …

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 …

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-CH_{4 …}

Drag Coefficient Characterization Of The Origami Magic Ball (Inproceedings), Guanyu Chen, Dongsheng Chen, Jessica Weakly, Cynthia Sung

Lab Papers (GRASP)

The drag coefficient plays a vital role in the design and optimization of robots that move through fluids. From aircraft to underwater vehicles, their geometries are specially engineered so that the drag coefficients are as low as possible to achieve energy-efficient performances. Origami magic balls are 3-dimensional reconfigurable geometries composed of repeated simple waterbomb units. Their volumes can change as their geometries vary and we have used this concept in a recent underwater robot design. This paper characterizes the drag coefficient of an origami magic ball in a wind tunnel. Through dimensional analysis, the scenario where the robot swims underwater …

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 …

Combined Behavioral And Engineering Approach To Preventing Highway Fatalities, Benjamin Blandford, Reginald Souleyrette, Caitlin N. Pope, Tony Fields, Erin Lammers-Staats

Kentucky Transportation Center Research Report

Traditional, single-discipline highway safety approaches can be augmented through multidisciplinary approaches that consider both engineering and behavioral interventions (e.g., education, enforcement, public outreach campaigns). Leveraging a systems-based conceptual framework of roadway safety, multiple forms of statistical and geospatial analysis, and SPF modeling and network screening, this report proposes and demonstrates methods for unpacking the influence of behavioral-related factors on crash occurrences and outcomes. The primary focus is on behaviors targeted in the Strategic Highway Safety Plan — aggressive driving, distracted driving, impaired driving, and driving without proper restraint (i.e., seatbelts). Based on application of these methods, the report highlights areas …

Developing Firmware For Space Weather Probes 2 Using Hdl Coder, Nicholas L. Wallace

All Graduate Theses and Dissertations

GPS and wireless communications are affected by interference from the ionosphere. Space weather affects plasma in the ionosphere, causing communication disruptions and reliability issues. To better understand how space weather affects the ionosphere, instruments are flown in space to collect data about the electrical characteristics of plasma in the ionosphere. Space systems require a lot of time and effort to develop and test. This thesis explores how a high level tool can be used to simplify the process and some obstacles that still exist with developing some space systems. To do this, the firmware architecture of a new version of …

Surface-Functionalized Silica Nanocarriers For Mitigating Water Stress In Wheat And Benefiting The Root Microbiome, Anthony Cartwright

All Graduate Theses and Dissertations

Changes in climate and shifting patterns of drought threaten the growth of important cash crops like wheat. The element silicon serves as a plant nutrient and shows promise for strengthening wheat against drought while remaining safe to both the crop and the positive bacteria that grow on its roots. Silicon can be added to wheat in the form of silicon-dioxide nanoparticles featuring protective coatings made from plant-beneficial nutrients. These nanoparticles can be engineered with high surface area or porous structures allowing them to be loaded with additional nutrients that can be delivered to crops. In a laboratory setting, such nanoparticles …

Effect Of Internal Curing And Shrinkage-Mitigating Materials On Microstructural Characteristics Of Fiber-Reinforced Mortar, Kamran Aghaee, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Internal curing (IC) and other shrinkage mitigating materials are employed to reduce shrinkage and risk of cracking. This study investigates the efficiency of individual versus combined use of IC and shrinkage mitigating materials on key characteristics of fiber-reinforced mortar (FRM). The investigated mixtures include a 25% pre-saturated lightweight sand (LWS) that is added individually and combined with 10% CaO-based expansive agent (EA) and 2% shrinkage reducing admixture (SRA). This elucidates the synergistic effect of high content IC and EA/SRA on macro- and micro-mechanical characteristics of FRM, especially at the interface of the matrix with fibers. Mechanical properties, microstructural characteristics, and …

A Strong And Ductile Cobalt-Free Solid-Solution Fe30ni30mn30cr10 Multi-Principal Element Alloy From Hot Rolling, Hans Pommerenke, Jiaqi Duan, Nathan Curtis, Victor Delibera, Adam Bratten, Andrew Hoffman, Mario F. Buchely, Ronald J. O'Malley, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Most of the Face-Centered Cubic (FCC) Multi-Principal Element Alloys (MPEAs) Developed Thus Far Contain Cobalt. for Many Applications, it is Either required or Beneficial to Avoid Cobalt, Since Cobalt Has Long-Term Activation Issue (For Nuclear Applications), is Expensive, and is Considered a Critical Material. in Addition, FCC Structured Solid-Solution MPEAs Tend to Have Relatively Low Strength. a FCC Solid-Solution Fe30Ni30Mn30Cr10 (At %) MPEA Was Fabricated Via Arc Melting, Followed by Homogenization at 1100 °C for 12 H. the Alloy Was Hot Rolled at 1100 °C with a Total Reduction of Up to 97 %. the Microstructure Was Characterized and Mechanical …

Prediction Of Compressive Strength And Evaluation Of Different Theoretical Standards And Proposed Models Of Brick Columns Confined With Frp, Frcm, Or Srg System, Zuhair Al-Jaberi, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Strength Capacity of Confined Masonry Column is One of the Topics that Need to Be Studied. in This Study, the Efficiency of using Different Types of Advanced Composite (Non-Corrosive Materials) Such as Fiber Reinforced Polymer (FRP), Fiber Reinforced Cementitious Matrix (FRCM), or Steel Reinforced Grout (SRG) in Confining Masonry Columns is Investigated. a Wide Range of Experimental Database of Masonry Column Specimens Has Been Collected from the Results that Available in Scientific Literatures. Different Theoretical Standards and Proposed Models that Used to Predict the Capacity of Masonry Columns Confined with FRP and FRCM Are Evaluated based on Collected Experimental …

A Case Study Of The Comparison Between Rubberized And Polymer Modified Asphalt On Heavy Traffic Pavement In Wet And Freeze Environment, Dongzhao Jin, Kwadwo Ampadu Boateng, Dongdong Ge, Tiankai Che, Lei Yin, Wayne Harrall, Zhanping You

Michigan Tech Publications

Ground tire rubber (GTR) usage in asphalt pavement with the dry process has gained more prominence in recent times. The objective of this work is to investigate the pavement performance of GTR-modified asphalt pavement and polymer-modified asphalt pavement on heavy volume of traffic conditions in Michigan's wet and freeze environment. A suite of laboratory tests was done to evaluate the pavement performance of GTR-modified and polymer-modified asphalt mixtures. To reveal the strain and stress relationship under different frequencies and temperatures, the dynamic modulus test was applied. The Hamburg wheel tracking device (HWTD) was used to assess the high-temperature deformation resistance. …

A Review Of Solar Hybrid Photovoltaic-Thermal (Pv-T) Collectors And Systems, Todd Otanicar

Mechanical and Biomedical Engineering Faculty Publications and Presentations

In this paper, we provide a comprehensive overview of the state-of-the-art in hybrid PV-T collectors and the wider systems within which they can be implemented, and assess the worldwide energy and carbon mitigation potential of these systems. We cover both experimental and computational studies, identify opportunities for performance enhancement, pathways for collector innovation, and implications of their wider deployment at the solar-generation system level. First, we classify and review the main types of PV-T collectors, including air-based, liquid-based, dual air–water, heat-pipe, building integrated and concentrated PV-T collectors. This is followed by a presentation of performance enhancement opportunities and pathways for …

Spatial Autocorrelation Analysis For Construction Sites, Raghda Moharram

Theses and Dissertations

This study investigates the usefulness of spatial autocorrelation analysis in construction sites. The objective is to provide construction managers with insights into the site's performance, identify potential areas for improvement, and ultimately lead to cost and time savings and improved project quality. To achieve this objective, the study identifies significant spatial autocorrelation variables for various applications in construction and analyzes their impact on the site's efficiency and potential problems.

The potential applications where spatial autocorrelation analysis could be useful were identified, including schedules, progress, earned value measures, safety incidents, workers' densities, equipment densities, energy expenditure, and quality non-conformity. A framework …

Predictive Models For Concrete Cone Capacity Of Cast-In Headed Anchors In Geopolymer Concrete, Trijon Karmokar, Alireza Mohyeddin, Jessey Lee

Research outputs 2022 to 2026

The scope of current state-of-the-art prediction models for concrete cone capacity of cast-in headed anchors is limited to normal concrete. In this study, the difference in the tensile performance of cast-in headed anchors embedded in ambient-temperature cured fly ash-based geopolymer concrete and normal concrete is investigated using both experimental and numerical analysis. The concrete cone capacity obtained for anchors investigated in this study is compared with current prediction models namely: Concrete Capacity Design (CCD) model, which overestimated the results by a maximum of 41%, and Linear Fracture Mechanics (LFM), which underestimated the results by a maximum of 53%. Anchors of …

Rejuvenation Effect Of Aged Sbs-Modified Asphalt Utilizing Molecule Analysis, Ke Shi, Feng Ma, Jenny Liu, Zhen Fu, Ruimeng Song, Dongdong Yuan, Chen Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Performance of Styrene-Butadiene-Styrene Modified Asphalt (SBSMA) is Significantly Impacted by its Aging and Regeneration. in This Research, the Molecular Dynamics Simulation Was Utilized to Investigate the Rejuvenation Effect of Active Reagents on Aged SBS Modified Asphalt through the Following Tasks: 1) Verifying the Accuracy of the Asphalt Model by Density and Solubility Parameters; 2) Assessing the Changes in the Rejuvenated Asphalt Model's Energetic Parameters and Volume Parameters, 3) Studying the Interaction Energy between SBS Molecules and Asphalt Molecule Models, and 4) Evaluating the Relative Concentration, Interfacial Interaction Energy, and Diffusion Effect of the Asphalt-Asphalt Models. the Results Indicated that …