Mechanical Engineering Commons^™

Speech Coding Based On A Hybrid Approach: Dct, Huffman And Run-Length Coding, Sundos Abdulameer Alazawi, Esraa Jaffar Baker, Shahbaa Mohammed Abdulmaged

Al-Esraa University College Journal for Engineering Sciences

The exponential expansion of data in the digital world necessitates the development of effective methods for data transmission and storage. Data compression (DC) strategies are suggested to reduce the quantity of data stored or conveyed due to constrained resources. As a result of DC ideas' ability to efficiently use existing storage space and transmission capacity, different methods have been developed in various areas. Speech coding is a lossy method of coding; therefore, the output signal differs slightly from the input signal. Speech coding is useful for message encryption, communication over long distances and speech quality. In the fields of digital …

The Evolution Of The University Of Al-Anbar Urban Planning Based On The Mental Picture's Diversity And The Contemporary Planning Spaces Filling, Ali Abdulsamea Hameed

Al-Esraa University College Journal for Engineering Sciences

This research concentrated on the role of environmental graphic design (EGD) and the place-making idea in the interior environment of Al-Anbar University. To develop an identity being visual for the University of Al-Anbar internal environment (IE) is this goal of project. The search sought to create and enhance the shape of the internal University of Al-Anbar vacuum by reviving the idea of place building. In order to build and filling the internal emptiness of the campus, the identity being visual must also be strengthened. The descriptive analytical approach was chosen since it was best suited to achieve the goal of …

Wood-Plastic Composites Integration For Triboelectric Nanogenerator Electricity Generation, Hanbyeol Park, Razamala Yashna F. Dimaporo, Sophia Maureen A. Emperado, Anton Jefferson L. Pangilinan, Juan Carlo T. Gumangan

Sinaya: A Philippine Journal for Senior High School Teachers and Students

Access to electricity in underdeveloped communities is particularly crucial in improving the living standards of people and alleviating poverty by promoting sustainable development. This study deals with the exploration of incorporating wood-plastic composite (WPC) – specifically wood pulp (W) and high-density polyethylene (H) – into triboelectric nanogenerator (TENG) flooring system to convert mechanical energy to electrical energy, promoting sustainable energy, reducing greenhouse gas emissions, improving the quality of life, and serving as feasible flooring tiles. Two types of TENG tiles were prepared by using different WPC ratios: 30W:70H and 70W:30H. A static bending test was conducted to assess the flexural …

Effects Of Negative Poisson’S Ratio On The Mechanics Of Auxetic Carbon Fiber Composites Under Tensile, Buckling And Low Velocity Impact, Wenhua Lin

Dissertations - ALL

Carbon fiber reinforced polymer (CFRP) matrix composites exhibited superior properties, such as high specific stiffness and specific strength, excellent fatigue and corrosion resistance, and low coefficient of thermal expansion, have been popular across various industries including aerospace, marine, automotive, energy, civil infrastructure, and high-end sports over the past decades. However, one significant drawback of CFRP composites is the susceptibility to low velocity impact damage which, for aircraft, can be results of tool drop, runway debris, and bird strike during takeoff and landing. These impact events could lead to external and internal damages of a CFRP composite structure in various damage …

Pan-Cancer Analysis Of Rna Dysregulation, Somatic Mutations, And Matrix Stiffness Using Bioinformatics Approaches, Gongyu Tang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cancer is a complex disease driven by genetic mutations, epigenetic modifications, and alterations in the tumor microenvironment. Understanding these intricate molecular mechanisms is crucial for advancing cancer diagnosis, prognosis, and treatment. RNA sequencing (RNA-seq) has emerged as a powerful tool to study cancer by providing comprehensive insights into gene expression, alternative splicing, and mutations at the transcriptome level. This dissertation leverages RNA-seq data to explore different dimensions of cancer biology through multi-omics integration and computational approaches. The research is divided into three main projects. First, I developed OncoDB, an interactive database to analyze gene expression, methylation patterns, and viral interactions …

Discrete Element Method For Mining Industrial Applications: Solving The Clumping Problem Caused By Bulk Cohesive Particles In An Iron Ore Beneficiation Process, Shuang Liu

McKelvey School of Engineering Graduate Student Theses & Dissertations

The discrete element method (DEM) is a widely used numerical approach for simulating and analyzing the behavior of granular materials in various applications. This research focuses on the iron ore beneficiation process, addressing the clumping issue in cohesive iron ores from existing crushing processes through a novel double-layered disperser design. The significance of this study lies in its potential to enhance the efficiency of the existing crushing phase and improve the linkage to subsequent purification stages that target smaller-sized iron ore pellets, thereby enhancing the overall efficiency of the ore beneficiation process and achieving significant energy savings. This research adopts …

Pan-Cancer Analysis Of Rna Dysregulation, Somatic Mutations, And Matrix Stiffness Using Bioinformatics Approaches, Gongyu Tang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cancer is a complex disease driven by genetic mutations, epigenetic modifications, and alterations in the tumor microenvironment. Understanding these intricate molecular mechanisms is crucial for advancing cancer diagnosis, prognosis, and treatment. RNA sequencing (RNA-seq) has emerged as a powerful tool to study cancer by providing comprehensive insights into gene expression, alternative splicing, and mutations at the transcriptome level. This dissertation leverages RNA-seq data to explore different dimensions of cancer biology through multi-omics integration and computational approaches. The research is divided into three main projects. First, I developed OncoDB, an interactive database to analyze gene expression, methylation patterns, and viral interactions …

Discrete Element Method For Mining Industrial Applications: Solving The Clumping Problem Caused By Bulk Cohesive Particles In An Iron Ore Beneficiation Process, Shuang Liu

McKelvey School of Engineering Graduate Student Theses & Dissertations

The discrete element method (DEM) is a widely used numerical approach for simulating and analyzing the behavior of granular materials in various applications. This research focuses on the iron ore beneficiation process, addressing the clumping issue in cohesive iron ores from existing crushing processes through a novel double-layered disperser design. The significance of this study lies in its potential to enhance the efficiency of the existing crushing phase and improve the linkage to subsequent purification stages that target smaller-sized iron ore pellets, thereby enhancing the overall efficiency of the ore beneficiation process and achieving significant energy savings. This research adopts …

Development Of A Model For Fire Spread In Low-Gravity Conditions, Kathleen Martinus

The Journal of Purdue Undergraduate Research

No abstract provided.

Optimization Of Tps Films Using An Adaptive Design Of Experiments Approach In A Bayesian Optimization Framework, Theresa Marks, Gracie White, Scott Lohman, Mayank Malhotra

The Journal of Purdue Undergraduate Research

Plastic pollution, amounting to 12 million tons annually, necessitates sustainable alternatives to single-use plastics. Compostable thermoplastic starch (TPS) films show promise but lack strength and durability compared to traditional plastics. This study employs an adaptive design of experiments (DoE) approach to enhance TPS films by optimizing testing points. The research focuses on varying concentrations of plasticizers (acetic acid and glycerol) in a water and potato starch mixture, aiming to identify the optimal ratio maximizing tensile strength and % elongation at break. Gaussian process regression (GPR) with uncertainty estimation and Bayesian optimization (BO) utilizing an acquisition function (AF) are employed. The …

Zeolite 13x Particles With Porous Tio2 Coating And Ag2o Nanoparticles As Multi-Functional Filler Materials For Face Masks, Wei Su, Kaiying Wang, Han Yu, Fateme Fayyazbakhsh, Jeremy Watts, Yue-Wern Huang, Jee-Ching Wang, Xinhua Liang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Adsorbent components in face masks are crucial for protecting individuals exposed to dangerous situations. In this study, one porous TiO₂ layer was deposited on zeolite 13X particles by coating hybrid organic/inorganic titanium alkoxide film via molecular layer deposition (MLD), followed by heat treatment to remove organic components in the MLD film. Various concentrations of Ag₂O nanoparticles were impregnated on the TiO₂-coated 13X particles, offering a wide range of antibacterial, antifungal, and antiviral characteristics. The obtained composite particles were characterized using X-ray photoelectron spectroscopy and thermal gravimetric analysis to study the composition and mass loading of …

Evaluation Of Electrode Configurations For (0,2) Piezoelectric Ultrasound Transducers, Abdul Qayoum Popal

Mechanical Engineering ETDs

Piezoelectric micro ultrasound transducers (PMUT array) are pivotal in MEMS applications. They typically operate in the fundamental (0,1) acoustic mode and are not significantly researched for higher modes (0,2) and (0,3). Similarly, vibrating mesh atomizers (VMAs) demand the second (0,2) mode and third mode (0,3) for effective aerosol generation, highlighting the need for optimized electrode configurations—a relatively unexplored area. This study presents the first comprehensive analysis of how electrode designs influence PMUT performance in the (0,2) mode for VMA applications.

Utilizing COMSOL multiphysics finite element modeling (FEM) with residual stress considerations alongside experimental validation, we demonstrate that optimized electrode configurations …

Application Of Digital Rock Physics And Machine Learning To Improve The Understanding Of Fluid Flow Behavior Through Porous Media, Md Irfan Khan

Mechanical Engineering Theses

Accurately estimating reservoir rock properties and understanding capillary trapping mechanisms are crucial for fluid storage and flow modeling in porous media, particularly for applications such as carbon dioxide sequestration (CCS) and underground hydrogen storage (UHS). This thesis presents a comprehensive workflow that combines machine learning techniques and pore-network modeling approach to predict petrophysical properties and assess the impact of microscopic pore structures on capillary trapping. In the first part, a convolutional neural network (CNN) framework is used to predict rock properties—such as porosity, throat area, and pore surface area—from micro-computed tomography (micro-CT) X-ray images. It has been observed that incorporating …

Numerical Simulations On Rayleigh Taylor Instability For Co2 Sequestration In Saline Aquifers, Bhargavi Vandadu

Mechanical Engineering Theses

The density-driven convection appears promise for CO₂ storage, precise prediction on a reservoir size is problematic due to limited data availability. Changes in permeability impact flow patterns and the effectiveness of mixing processes. Permeability differences influence the sorts of density-driven mixing phenomena such as fingering and stable mixing. Improving CO₂ storage models is challenging due to the unpredictable nature of these processes. The study looks at the flow phenomena in which carbon dioxide with a lower viscosity displaces on heavier fluid water. Causes instability by producing finger-like structures at the gas-liquid interface. This study uses the species transport technique to …

Crystal Plasticity Modeling To Capture Microstructural Variations In Cold-Sprayed Materials, Aulora Gail Williams

Theses and Dissertations

The high-velocity impact of powder particles in cold-spray additively manufactured (CSAM) parts creates intersplat boundaries with regions of high dislocation densities and sub-grain structures. Upon microstructure and mechanical characterization, CSAM Aluminum 6061 showed non-uniformity, with spatial variation in the microstructure and mechanical properties affecting the overall response of the additively manufactured parts. Post-processing treatments are conducted in as-printed samples to improve particle bonding, relieve residual stresses, and improve mechanical properties. In this work, we attempt to implement the effects of grain size and distribution of smaller grains along the intersplat boundaries using the grain size distribution function and powder size …

Experimental And Numerical Investigation Of Phase Change Material Melting Cycle In Microgravity, Ethan Michael Schuetzle

Theses and Dissertations

Efficient thermal management of spacecraft systems is crucial to overcome the extreme thermal conditions in space. Phase change materials (PCMs) offer significant advantages in thermal energy storage (TES) systems due to their high latent heat of fusion, the amount of energy stored or released during phase transitions. However, PCMs face limitations due to low thermal conductivity, especially in microgravity where heat transfer is primarily through conduction. This research addresses this issue by incorporating a 3D-printed aluminum lattice structure to enhance heat transfer to PCMs. Experimental data from sub-orbital flight tests and ground-based experiments, coupled with numerical simulations, are used to …

Jovial Family Farm Facilitates Intergenerational Learning Opportunities Through Urban Farming, Maera Williams

Purdue Journal of Service-Learning and International Engagement

Maera Williams is a sophomore in Environmental and Ecological Engineering at Purdue University. She joined the Engineering Projects in Community Service (EPICS) Urban Farming team as a freshman and now serves as project manager of ten undergraduate students collaborating with Jovial Family Farm to design and develop three indoor hydroponics systems for a laboratory space on their property in Broad Ripple, IN. Jovial Family Farm is a nonprofit organization founded by Drs. Bobbie and Brian Jellison with the mission to provide senior citizens, their families, and their communities with meaningful engagement opportunities on an intergenerational scale through urban agricultural activities. …

Predictive Modeling And Sustainability Assessment Of Hydrothermal Liquefaction Of Seaweeds: A Techno-Economic And Life Cycle Analysis Approach, Micheal O. Asama

Mechanical Engineering Theses

This study presents comprehensive predictive models and an economic and environmental assessment of HTL for converting macroalgae into biofuels and valuable co-products. Predictive models were developed based on experimental kinetic data to simulate batch HTL of brown seaweed, capturing the yields of biocrude, gas, biochar, and water-soluble compounds as functions of key process variables, including temperature, time, pressure, and water-to-biomass ratio. Analysis of Variance (ANOVA) confirmed that temperature and residence time significantly affect biocrude yield, with an optimal yield of 23% achieved at 283°C, 200 bar, 54 minutes, and a 10:1 water-to-biomass ratio. The model’s predictive accuracy was validated with …

Direct Methanol Fuel Cells Using Pure Methanol, Ryan Spragg

McKelvey School of Engineering Graduate Student Theses & Dissertations

Fuel cell technology has attained significant appeal as a form of renewable energy in recent years due to its diverse applications, various fuel types, and lower greenhouse gas emissions. Of the various fuel cell types, direct methanol fuel cells (DMFCs) hold a set of distinct advantages for stationary and small portable applications. These advantages include faster refueling compared to battery charging, high gravimetric energy density, and ease of production and use compared to hydrogen. However, the DMFC has numerous technical hurdles that prevent its widespread adoption into the commercial market. Namely, the slow reaction kinetics in the anode and the …

Custom Cathode Optimization For Electropolishing Additively Manufactured 316l Stainless Steel, Kasandra Escarcega Herrera

Mechanical Engineering ETDs

Laser powder bed fusion (LPBF) has become increasingly popular for its ability to rapidly manufacture complex metallic parts. However, the surface properties of as-built LPBF parts may degrade overall performance due to tortuous surface features. Consequently, post-processing like electropolishing (EP) to reduce the surface asperities is often needed for LPBF parts to perform as expected. Utilizing experimental and computational approaches, this project aims to more uniformly EP complex shaped parts made from LPBF 316L. For the experimental approach, parts with a three-dimensional T-shape were printed out of 316L stainless steel and EP using an acidic-based and a polyethylene glycol/NaCl-based electrolyte. …

Understanding Confusion: A Case Study Of Training A Machine Model To Predict And Interpret Consensus From Volunteer Labels, Ramanakumar Sankar, Kameswara Mantha, Cooper Nesmith, Lucy Fortson, Shawn R. Brueshaber, Candice Hansen-Koharcheck, Glenn Orton

Michigan Tech Publications

Citizen science has become a valuable and reliable method for interpreting and processing big datasets, and is vital in the era of ever-growing data volumes. However, there are inherent difficulties in the generating labels from citizen scientists, due to the inherent variability between the members of the crowd, leading to variability in the results. Sometimes, this is useful — such as with serendipitous discoveries, which corresponds to rare/unknown classes in the data — but it might also be due to ambiguity between classes. The primary issue is then to distinguish between the intrinsic variability in the dataset and the uncertainty …

Microstructured Microstructure: Effects Of Concentration Variations On Shock Initiation Of Hmx-Based Plastic Explosives, Dana D. Dlott, Lawrence Salvati, Siva Kumar Valluri

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We studied shock-compressed plastic-bonded explosives (PBX) consisting of HMX (cyclotetramethylene-tetranitramine) with PDMS (poly-dimethylsiloxane) binder, where we varied the HMX weight percent (wt%) up to a maximum of 60 wt%. In this lower-concentration regime, HMX particle clustering causes the PBX structure to consist of HMX clusters and PDMS islands. Structural analysis by optical microscopy allowed us to compute a radial correlation function that gives the mean distance from an average HMX particle to the nearest polymer island. Short-duration 20 GPa shocks (4 ns) created hot spots, and time-resolved thermal emission was used to obtain the growth rate of the subsequent deflagration. …

Accelerating Shock-Driven Reactions In Metal Nanocomposites, Siva Kumar Valluri, Edward L. Dreizin, Dana D. Dlott

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metal powders are sought as energetic additives to conventional explosives. However, due to their sluggish reaction kinetics with external gaseous oxidizers, pure metals are replaced with metallic composites with intimately mixed condensed phase oxidizers prepared by arrested reactive milling (ARM). Such composites can be initiated by non-thermal, mechanical means; through shear mixing of fuel and oxidizer under a shock compressive load. Since the ARM preparatory technique allows for tuning multiple powder attributes such as fuel/oxidizer of interest, their degree of mixing, amount of oxidizer, particle porosity, among others, a parametric study is crucial in identifying suitable traits for fast reactions …

Mems 411: Electrostatic Precipitator Design For Washu Racing Composites Team, Robert J. Wild, Takato Muro, Jackson Ford, David Wiggin

Mechanical Engineering Design Project Class

The objective of this paper is to develop an effective method to remove carbon fiber particulates from the air in the WashU Racing garage using electrostatic precipitation.

Mems 411: Talking Goniometer, Jeffrey Reinhold, Matthew Ren, Corin Riahi, Moises Rodriguez

Mechanical Engineering Design Project Class

Our project is about designing a goniometer that will aid Rachel Apter, an occupational therapy graduate student, more easily determine the angles created by limbs bending about a joint. A goniometer is essentially a protractor designed to affix its base arm to a stationary limb and it’s rotating arm to a moving limb. The moving arm follows the moving limb, measuring the coupled limb’s range of motion. The main complaint centering around goniometers is that they are hard to read due to the small tick marks that indicate the angle. To fix this problem, the goniometer will be edited to …

Mems 411: The Ball Bearing Sorter Group N, Jack Zhao, Anri Cifuentes, Shawn Xiong, Richard Li

Mechanical Engineering Design Project Class

The challenge was to design and develop an automated device capable of sorting and packaging six types of ball bearings—varying in size (1/4 inch and 1/2 inch) and material (stainless steel, brass, and nylon). The device needed to meet strict performance and design constraints, including fitting within a compact 20x20x20-inch footprint, weighing no more than 15 pounds, and sorting bearings with high speed and accuracy.

This problem represents a practical scenario in automated manufacturing, where efficient and precise sorting is crucial for streamlining assembly line operations. The solution required integrating innovative engineering mechanisms, such as size differentiation, material separation, and …

Mems 411: Mailbox Assistant, Peter Scholl, Benjamin Cortes, Garbiel Arcas, Colin Zeiss

Mechanical Engineering Design Project Class

Oftentimes elderly people struggle with reaching into their curbside mailbox from their car, especially if the mail is pushed all the way to the back. With the Mailbox Assistant, sore shoulders can be saved through a drawer that slides out from the mailbox. This modification can be made to any mailbox without altering the outside appearance thus keeping it within HOA standards.

Mems 411: Hydroponic Gardening System, Tiger Lu, Aj Shanahan, Jaquelin Guzman, Brandon Lacy

Mechanical Engineering Design Project Class

This report summarizes the engineering design process undertaken for the development of a hydroponic gardening system. The project began with selecting a concept, as a team, we decided to focus on designing a system tailored to community gardening needs. The report is organized into five main sections: Problem Understanding, Concept Generation, Concept Selection, Concept Embodiment, and Design Refinement. In the Problem Understanding phase, the team conducted extensive research on patents, codes and standards, user needs, design metrics, and project management. This foundational research was critical to ensure all aspects were considered before beginning the building process. User needs were identified …

Mems 411: Diving Surface Breaker, Chandler Gartner, Freddy Phillips, Maya Sumra, Olivia Slemmer

Mechanical Engineering Design Project Class

We have been recruited by the WashU diving team to design and construct a surface breaker for the Millstone Pool so the divers can have an affordable way to stay safe while practicing dives.

Mems 411: Timed Mosquito Egg Container Design Project, Paige Warren, Witt Ciesla, Ethan Sobel

Mechanical Engineering Design Project Class

The goal of this project is to design and construct a device that allows for the controlled study of mosquito egg-laying behavior in response to artificial light and temperature variations. Specifically, the device will limit access to cups of standing water, which serve as egg-laying sites, to preprogrammed times of day over a 7-day period.
The device should ensure the following:

• Control Access: The container should be open and closed at predetermined intervals, allowing mosquitoes to access the cups of standing water only during these times.
• Programmability: It should be easy for a novice to specify the opening and closing …