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Dual-Band High Gain Circular Microstrip Array Antenna For Wireless Applications, Hassan Ali Ragheb, Mariam Hossam

Electrical Engineering

This paper presents the design of a compact, high-gain, dual-band microstrip antenna array composed of four circular patch elements. Traditional antenna arrays employ linear or planar configurations, where the feed network plays a key role in shaping the beamwidth and sidelobe level. In contrast, this design achieves compactness by nesting a small-scaled two-element linear array within a larger two-element linear array. Each radiating element is a circular microstrip patch designed for operation at 3.1 GHz and 6.9 GHz, aligning with IEEE 802.11b/g wireless communication standards. The full array configuration operates over dual bands, covering (3.05–3.18) GHz and (6.9–7.0) GHz, and …

Tribology Of Textured Surfaces, Min Zou, Mahyar Afshar-Mohajer, Robert A. Fleming

Mechanical Engineering Faculty Publications and Presentations

Surface texturing has emerged as a transformative approach to improving friction, lubrication, and wear across a wide range of mechanical components. From bio-inspired micro-dimples to engineered macro-grooves, texture designs are increasingly applied in biomedical implants, bearings, seals, and automotive systems. This Special Issue, “Tribology of Textured Surfaces,” compiles 14 papers that collectively cover fabrication techniques, multi-scale optimization, predictive modeling, and diverse application areas.   The following sections summarize the major themes of this Special Issue. Section 2 reviews the fabrication techniques and texture scales addressed by the authors. Section 3 examines modeling and numerical studies, while Section 4 categorizes the work …

Modeling Steady-State Navier-Stokes Flow Using Structure-Preserving Truncated Hierarchical B-Splines, Daira Sofia Velasco Vega

Theses and Dissertations

Accurate simulation of incompressible steady-state fluid flow is critical for engineering applications where mass conservation, numerical stability, and geometric fidelity are essential. This thesis develops and analyzes a structure-preserving isogeometric framework for steady-state incompressible Navier"“Stokes simulations using truncated hierarchical B-splines (THB-splines). By leveraging divergence-conforming spline spaces designed to keep the fluid's divergence exactly zero based on the mathematical de Rham complex, this method ensures the fluid remains incompressible everywhere without needing extra stabilization techniques. The use of THB-splines allows the mesh to be refined locally in areas where the flow changes sharply. It still keeps the solution smooth and ensures …

Translating Soil Salinity To Agricultural Salt Stress: Key Salt-Tolerance Mechanisms For Agrohydrologic Models, Josh Gottlieb, Dvir Ochman, Cheng-Wei Huang, Jean-Christophe Domec, Nimrod Schwartz, Samantha Hartzell

Civil and Environmental Engineering Faculty Publications and Presentations

Summary:

Salt stress has a detrimental impact on crop yield and survival rates, which salt-tolerant cultivars can resist through numerous adaptive mechanisms. Most models of salt stress impacts on productivity and water use employ empirical or simplified schemes to represent salt-adaptive traits. However, with an increased understanding of these physiological tolerance mechanisms and emergent measurement techniques for monitoring key salinity dynamics, the potential for developing mechanistic agrohydrological models of the soil-plant-atmosphere continuum has grown. This perspective highlights strategies for modeling salt tolerance mechanisms, including root system architecture adaptation, salt filtration, adaptation of plant hydraulics, ion compartmentalization, and stomatal responses, to …

Coal Mining Reclamation: Lessons Learned From Tropical And Subtropical Countries, Priyaji Agung Pambudi, Suyud Warno Utomo, Roni Setyo Handoko

Journal of Environmental Science and Sustainable Development

This study addresses the persistent environmental challenges associated with coal mining in tropical and subtropical regions, where complex microclimates and ecological variability hinder effective reclamation. Despite the increasing global coal demand, comparative cross-country insights remain limited. This research fills the gap by evaluating the best practices. This study employs a qualitative methodology with a comparative case study design, uses systematic literature review to evaluate ecology based reclamation policies and implementation practices. Data were sourced from peer-reviewed journals from Scopus and the Web of Science database and institutional reports, and analyzed using McHarg’s landscape ecology theory to evaluate reclamation policies, ecological …

Studies Of Electrical Breakdown Of High-Pressure Ultra-Zero Air, Seth Miller

Electrical and Computer Engineering ETDs

High-pressure ultra-zero air is being evaluated to enhance switch performance and serve as a potential replacement for SF$_6$ in high-voltage switches, aiming to reduce reliance on costly insulating gases with supply chain and environmental concerns. There are still uncertainties about the dominant breakdown mechanisms of ultra-zero air in the high-pressure regime. The classical equations for breakdown describing Paschen curves appear to not be valid above 500 psia. In order to better understand gas breakdown in the high-pressure regime, this dissertation is evaluating the basic gas physics breakdown using both uniform and nonuniform-field electrode designs. The data has been collected to …

Techno-Economic Analysis (Tea) And Life-Cycle Assessment (Lca) Of Sustainable Aviation Fuel (Saf) Production Through Circular Economy (Ce) Practices: A Focus On Supply Chain Optimization And Policy Implications, Edmund Gyandoh

Chemical and Biological Engineering ETDs

This study provides a comprehensive systems-level evaluation of an integrated circular biorefinery for sustainable aviation fuel (SAF) production. Employing supply chain optimization, technoeconomic analysis, lifecycle analysis, policy modeling, and multicriteria decision analysis, the research assesses technical feasibility, economic viability, and environmental performance. The circular economy model demonstrates exceptional resource efficiency, achieving a 92.3% overall circularity score with strong material recycling, water reuse, waste minimization, and near-complete energy recovery, resulting in net-negative carbon emissions and net energy export. Scaling the facility to commercial capacity (500 million liters per year) enables significant economic improvements. The minimum fuel selling price (MFSP) decreases from …

Design Of Directive Wideband Microstrip Antenna, Hassan Ali Ragheb

Electrical Engineering

The study under consideration demonstrates design, simulation, and optimization of a compact Ultra-Wideband (UWB) antenna employing a coplanar waveguide (CPW) feeding structure and a circular patch geometry. The design is targeting a 7 GHz operating frequency, offering a balance between compact size, wide bandwidth, and directional radiation characteristics. An initial antenna configuration was developed and analyzed using HFSS, showing satisfactory performance in terms of impedance matching and radiation efficiency. However, asymmetries in the radiation pattern prompted further enhancement. An improved design employees strategically director elements placed above the circular patch to improve forward gain and radiation beam directivity. The optimized …

Improving Echocardiographic Aortic Aneurysm Assessment In Marfan Syndrome Patients, Joshua Paik, Shubh P. Mehta, Samskrithi Sivakumar, Felix Dinklage, Ahhyun Lee, Benjamin J. Landis, Craig J. Goergen

Discovery Undergraduate Interdisciplinary Research Internship

Marfan syndrome (MFS) is a genetic connective tissue disorder caused by a variant of the fibrillin-1 (FBN1) gene, leading to abnormalities in organs reliant on tissue elasticity. Proximal thoracic aortic aneurysms (TAAs) are a major clinical concern, particularly in pediatric MFS patients, due to their risk of dissection or rupture. Diagnosis and monitoring of TAAs often depend on manual measurements of aortic root diameters from the parasternal long axis views of transthoracic echocardiograms. However, this method is prone to interobserver variability (IOV), which impacts consistency in clinical assessment. To mitigate these limitations, we developed a graphical user interface (GUI) that …

Non-Destructive Strength Monitoring Of Air-Entrained Concrete Via Electromechanical Impedance Technology, Xiangrui Kong, Rui He

Discovery Undergraduate Interdisciplinary Research Internship

Accurate monitoring of concrete strength during curing is crucial, particularly in regions subject to harsh weather conditions, such as freeze-thaw cycles in Indiana. Air entrainment is crucial for durability, yet it can significantly reduce concrete strength, making timely and precise strength assessments vital. The primary objective of this study is to develop a non-destructive and real-time monitoring framework for evaluating mortar strength using electromechanical impedance (EMI) sensors and ultrasonic scanning technology.

This research holds significant value as it addresses the critical need for continuous, reliable concrete strength monitoring, potentially reducing reliance on destructive testing methods, which are costly and time-consuming. …

Discovering And Designing Novel Perovskite Photovoltaic Materials Via Machine Learning, Junyeong Ahn

Discovery Undergraduate Interdisciplinary Research Internship

Perovskite semiconductors are promising materials for high-efficiency photovoltaics due to their outstanding optoelectronic properties, emerging as a sustainable energy source through solar cell applications. Perovskites with the ABX₃ composition (A, B = metal or organic cations with varying oxidation states; X = chalcogen or halogen anions) have gained interest for their excellent phase stability and compositional tunability. However, combinatorial possibilities arising from the many choices of A, B, and X site species, and their respective mixing fractions, a large number of possible ABX₃ perovskites remain undiscovered. In this work, we used machine learning (ML) methods to design new stable and …

Sex-Dependent Differences In Cardiac Function And Strain In Doxorubicin-Induced Cardiomyopathy, Anna J. A. Webb, Bea O. Cabot, Aasish Chowdary, Wilhelm S. Smith, Benjamin Zeidler, Cortland H. Johns, Craig J. Goergen

Discovery Undergraduate Interdisciplinary Research Internship

Doxorubicin is a chemotherapeutic agent used to treat many types of cancer. While effective, doxorubicin can cause cardiomyopathy, a disease affecting the heart muscle. Although the effects of doxorubicin on the heart are well studied, the mechanisms leading to cardiomyopathy are not well understood. Previous studies have used murine models to study the cardiotoxicity of doxorubicin. These reports showed that cardiac dysfunction is more pronounced in male compared to female mice. The goal of this study is to further evaluate sex differences in doxorubicin induced cardiomyopathy using 4-dimensional strain mapping techniques. In this study, both female and male C57Bl/6J mice …

Is There A More Effective Design For Quadrat To Increase Ease Of Use And Vegetation Density?, Scott M. Burke Jr., Kristen M Bellisario

Discovery Undergraduate Interdisciplinary Research Internship

Quadrats are a special tool in the ecology field that allows the measurement of vegetation density for further data analysis of a habitat. The larger the quadrat cross-sectional area, the better the results of the data, which in turn can make the quadrat hard to carry through field sites. In wildlife corridor research, quadrat surveys provide a quantitative metric for habitat suitability. In this work, we consider the efficiency and ease-of-use benefits for field work in the design of a collapsible version of a quadrat using a House of Quality (standard metric for new design requirements) to assess the customer …

A Dna Damage Analysis Of Breast Cancer Cells Under Cyclic Mechanical Actuation, Maria C. Macias, Madison Howard, Luis Solorio

Discovery Undergraduate Interdisciplinary Research Internship

Metastasis is the leading cause of mortality in breast cancer, yet tumor cell behavior and their response to mechanical cues in the pre-metastatic niche remains poorly understood. This study investigates how breast cancer cells respond to strain mimicking lung tissue dynamics, with a focus on DNA damage. Using a custom-designed micro-actuating lung model, we cultured mApple at p53BP1 and H2B-GFP reporter cells on fibrillar fibronectin-coated substrates subjected to cyclic mechanical forces that simulate respiratory motion. A group of cells were treated with escalating concentrations of Niraparib (0.1–10 µM), a PARP inhibitor, as a positive control. To visualize and quantify DNA …

Annual Maximum Snow Loads For Weather Stations Outside Of The Conterminous United States, Nicholas Brimhall, Brennan L. Bean, Marc Maguire, Bikram Bhusal, Maha Moussa

Browse all Datasets

Historical records of snow observations are critical for civil engineering, climate modeling, and risk assessment. While a robust dataset of annual maximum snow loads has been developed for the conterminous United States, a similar dataset does not exist for areas of interest in areas outside of the conterminous United States (OCONUS). This dataset contains over 280,000 annual maximum SWE values across over 7,400 OCONUS stations, both from the Global Historical Climatology-Daily (GHCND) network provided by the National Oceanic and Atmospheric Administration (NOAA) and from country-specific networks of weather stations from international meteorological agencies. This dataset will be valuable for civil …

A Novel, Metal-Based Approach To Identify Residences With Lead Service Lines, Danielle Land, Grant D. Brown, David M. Cwiertny, Marc A. Edwards, Mona Hanna, Drew E. Latta, Michelle M. Scherer

Michigan Tech Publications

There is an urgent need for rapid, cost-effective approaches to identify residences with lead service lines (LSLs). We evaluated whether analyzing water for corrosion-related metals could accurately identify residences with LSLs without relying on potentially inaccurate property records. We applied principal component analysis logistic regression (PCA-LR) and classification tree models using 28 analytes per bottle (including Pb, Cu, Zn, Fe, Al, and others) measured in 216 water samples collected in Flint, Michigan, in August 2015. The PCA-LR model achieved 87% accuracy (AUROC = 0.93) with 81% sensitivity and 90% specificity, while the classification tree model achieved 80% accuracy (AUROC = …

Effects Of Long-Term Exposure On Composite Manufactured Marine Propellor Blades In Pure Distilled Water And Artificial Seawater, Jacob Brady

The Plymouth Student Scientist

The aim of this research was to establish the feasibility and investigate the mechanical challenges of the use of composite materials for a marine propellor. Focusing on the major challenge of hygroscopic swelling and the effect this has on material dimensions and properties. Flax-epoxy and carbon-epoxy samples were manufactured and tested in distilled water and artificial seawater to establish the effects of hygroscopic ageing over long-term exposure. Accelerated ageing at 60°C was used to minimise experimental duration whilst observing long-term effects. The research also identified proposed values for the co-efficient of hygroscopic expansion in three planes of 2x2 twill weave …

Utilization Of Biomass From Kerai Payung Trees And Waste Paper Through Pyrolysis Technology To Support The Zero-Waste Concept, Anggita Putri Indadari, Nurfa Anisa, Asih Budi Santoso

Journal of Mechanical Engineering Science and Technology (JMEST)

Wisnuwardhana University is a private institution with a green campus environment surrounded by Kerai Payung trees. This environment produces organic waste from trees and inorganic waste such as used paper from campus activities. This study aims to achieve zero-waste processing by using pyrolysis technology to process campus waste, ensuring minimal residue. The experimental method involves comparing waste processing outcomes between conventional combustion and pyrolysis, the data was analyzed by comparing the results of pyrolysis with conventional combustion. The results of biochar from the pyrolysis process of used paper, Kerai Payung leaves, and nagging Kerai Payung tree are 76 g, 250 …

Predicted Inelastic Response Of Conventional And Ductile Steel Concentrically Braced Frame Buildings Under Wind Loads, Conrad Hamblin Belshe

Theses and Dissertations

The inelastic response of three-story steel concentrically braced frame buildings under wind loads was simulated to determine the applicability of ductile braced frame design to wind load applications. This study examined three types of steel concentrically braced frames: a conventional braced frame, a ductile braced frame, and a ductile braced frame with a reduced beam requirement. Braced frames were designed for four design wind speeds (220 mph, 156 mph, 127 mph, and 110 mph), for a total of nine unique braced frame designs. Nonlinear static pushover analysis was used to determine system overstrength and ductility under wind loads. Eigenvalue vibration …

Investigation Into Intraocular Pressure Distribution Via Computer Aided Engineering (Cae), Madison Maureen Hinman

Masters Theses

The leading cause for irreversible blindness and vision loss is glaucoma - an eye condition associated with elevated intraocular pressure (IOP). Increased IOP is also seen during other pathological conditions like spaceflight-associated neuro-ocular syndrome (SANS), and non-pathological conditions as when playing a wind instrument. The study aimed to describe the influence of different vitreous cavity size as well as vitreous fluid viscosity on the IOP as measured at the back of the eye on the retina. Improved understanding of eye pressure transmission can aid in a better understanding of eye diseases. The experiment conducted included cavities of varying size and …

Effect Of Various Canopy Shapes On The Drag Coefficient Of Pickup Trucks, Khairil Anwar, Muhammad Syaiful Fadly, Muhammad Wahyu Hermanto

Journal of Mechanical Engineering Science and Technology (JMEST)

The aerodynamic performance of light commercial vehicles, such as the Suzuki Carry, plays a crucial role in their fuel economy and road stability. One typical add-on, a canopy, often changes that airflow and, as a result, alters the drag acting on the vehicle. In this study, three different canopy shapes, flat, curved, and triangular, were examined to understand how each one affects the drag coefficient (Cd). To investigate this, both wind tunnel trials and CFD runs were conducted to track the airflow and measure any changes in drag with greater detail. For reference, the exact vehicle without a canopy was …

Influence Of Different Nanoparticles On Thermophysical Properties And Wear Resistance Of Corn Oil-Based Cutting Fluid In Mql-Cnc Milling Machining, M Nuril Anwar Habiby, Poppy Puspitasari, Aminnudin Aminnudin, Diki Dwi Pramono, Ahmad Atif Fikri, Mariyam Jameelah Ghazali

Journal of Mechanical Engineering Science and Technology (JMEST)

Vegetable oil-based cutting fluids have emerged as a promising innovation in machining operations, supporting the advancement of sustainable and eco-friendly manufacturing practices. This study delves into the development of a biolubricant derived from corn oil, enriched with 0.15% mass fractions of various nanoparticles, including calcium carbonate (CaCO3), copper oxide (CuO), and multi-walled carbon nanotubes (MWCNT). These nano-cutting fluids were applied through the Minimum Quantity Lubrication (MQL) method during CNC milling of AISI 1045 steel. The investigation focused on evaluating thermophysical properties, including density, thermal conductivity, and dynamic viscosity, as well as tool wear performance. The results demonstrated that CuO nanoparticles …

Steam Supply Evaluation For Carbon Capture And Storage In A Subcritical Coal-Fired Power Plant, Veri Hendrayawan, Anggit Raksajati, Sanggono Adisasmito, Firman Bagja Juangsa

Journal of Mechanical Engineering Science and Technology (JMEST)

The aim of this study is to analyze the implementation of carbon capture and storage (CCS) in coal-fired power plants (CFPP) in Indonesia by determining the reboiler energy demand through steam source analysis. The study uses a representative 3×330 MW subcritical coal-fired power plant (CFPP), with an emission intensity of 1.02 tCO₂/MWh and flue gas CO₂ concentration of 13.8%. CCS modeling shows the reboiler requires about 2.9×10⁹ kJ/h energy, supplied by steam extracted from the plant’s steam cycle. A steam cycle model was developed to evaluate the impact of steam extraction. Potential tapping points analyzed include main steam, cold reheat, …

Development Of Power Management On Unmanned Surface Vehicles To Measure Battery Voltage And Power, Diana Alia, Henna Nurdiansari, Akhmad Kasan Gupron, Amelia Greacy Talenta Siregar

Journal of Mechanical Engineering Science and Technology (JMEST)

This research focuses on designing an electrical system for unmanned surface vehicles (USV) to ensure optimal performance during survey operations. This USV ship is a catamaran-type ship with a Sonar Deeper depth sensor to know the depth of the water and is equipped with long range (LoRa) as a data transmitter. The USV electrical system design incorporates the use of a 4050 mAh 11.1 V LiPo battery and an iMAX B6AC charger, with evaluations covering battery charging, power consumption, and voltage stability. The trials showed that the battery supported the operation of the USV for approximately 47.8 minutes at a …

Dynamic Analysis And Fatigue Life Evaluation Of Single Herringbone Planetary Gear System With Crack Fault, Dongping Sheng, Jie Yang, Chun Su

Journal of Mechanical Engineering Science and Technology (JMEST)

The herringbone planetary gear transmission is widely used due to its exquisite compact structure, excellent load-bearing capacity, and stable transmission characteristics. However, root crack is one of the most common failure modes of gears. A cracked herringbone planetary gear system is taken as research object. The sun gear with crack fault is studied from the aspect of modal and transient dynamic analysis, and the related results are compared with the healthy gear. Based on the transient dynamic analysis of the herringbone teeth with cracks, a fatigue life evaluation is conducted. Firstly, the results show that no significant difference between the …

Investigation Of The Influence Of Warhead Shape And Type Of Missile Weapon Material Counter-Training Tank Weapons Simulation Approach, Transisma Budiarta, Haris Puspito Buwono, Radhi Nurvian Amrullah

Journal of Mechanical Engineering Science and Technology (JMEST)

This study analyzes the effect of warhead shape and material variations on pressure, temperature, and lift on training missiles using CAD-based simulation methods. The variations of warhead shapes tested include flat, flat radius, and tapered, while the materials used are rubber, ABS, and PE. The simulation results show that the tapered warhead shape with PE material produces the lowest pressure (50.3 MPa) due to more efficient pressure release and low friction properties. Conversely, the Flat shape produces the highest pressure (69.1 MPa) on all materials due to flow stagnation. In terms of temperature, the Flat Radius warhead with PE and …

Investigation Of Drag Force And Downforce On Two Racing Motorcycles In Slipstream Conditions, Muhamad Hanifudin, Gaguk Jatisukamto, Mahros Darsin, Muh. Nurkoyim Kustanto, Azmi Saleh, Suprihadi Prasetyono, Catur Suko Sarwono

Journal of Mechanical Engineering Science and Technology (JMEST)

The performance of modern racing motorcycles is greatly influenced by their aerodynamics. Slipstreaming occurs during a race when a rider closely follows another, especially on a straight track. The effect can reduce aerodynamic drag and increase the overall speed of the rider behind. This study investigates the aerodynamic effects of slipstreaming on a racing motorcycle using computational fluid dynamics. This study also considers its effect on both drag force and downforce, which affects motorcycle stability. A 3D CAD model of a racing motorcycle and a rider in a crouching position was used as the object of research. CFD simulations were …

Characterization Of Curcumin As A Coating Material For Polymer-Free Stents Interms Of Morphology And Release, Ameliyana R.S.P.A. Yani, Muhammad Kusumawan Herliansyah

Journal of Mechanical Engineering Science and Technology (JMEST)

The use of bare metal stents over the long term often leads to the re-narrowing of blood vessels, prompting a shift to drug-eluting stents (DES). However, the use of polymers in DES has been known to trigger inflammation and thrombosis in the arteries. As an alternative, polymer-free drug-eluting stents (PF-DES) have emerged as a safer option. In this study, curcumin was selected as the primary coating material for PFDES using the electrophoretic deposition method. The effects of varying curcumin concentrations (125 µg/ml, 250 µg/ml, and 500 µg/ml) were examined to understand their impact on deposition morphology, coating weight, chemical bonding …

Impact Of Print Speed And Nozzle Temperature On Tensile Strength Of 3d Printed Abs For Permanent Magnet Turbine Systems, Wirawan Wirawan, Hilmi Iman Firmansyah, Satworo Adiwidodo, Mohammad Sukri Mustapa

Journal of Mechanical Engineering Science and Technology (JMEST)

Operational parameters must be integrated into turbine systems' main components, which are determined by turbine systems' functional requirements. The need for producing component designs more effectively raises the possibility of using additive manufacturing. The study focuses on the optimization of the mechanical properties of the principal components of magnetic turbines manufactured with 3D printers using Acrylonitrile Butadiene Styrene (ABS), by changing the temperature and speed of the nozzle. The approach consisted of modeling a standard test piece in CAD software and producing ABS-based test pieces using a 3D printer with print speeds of 50, 70, 90, and 110 mm/s and …

Performance Analysis Of Alkaline Fuel Cell With Variation Of Potassium Hydroxide Concentration In Electrolyte Solution, Mohammad Rifqy Alfariz, Nasrul Ilminnafik, Dwi Djumhariyanto, Intan Hardiatama, Muhammad Khadafi Ibnu, Raafi Aditya Nugraha, Domingos De Sousa Freitas

Journal of Mechanical Engineering Science and Technology (JMEST)

Alkaline Fuel Cell (AFC) is a green energy conversion tool that converts chemical energy into electrical energy through electrochemical reactions. This research aims to analyze the effect of potassium hydroxide (KOH) concentration variation in electrolyte solution on the AFC performance, using nickel and manganese catalysts. The research methods include experiments using various KOH concentrations to determine the optimal concentration to produce the best AFC performance. The voltage and current produced are measured, as well as the calculation of the electrical power and efficiency of the AFC. The results showed that KOH concentration has a significant influence on the performance of …