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Nebraska Test #2276: Case Ih Steiger 525 Quadtrac, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Test #2278: Case Ih Steiger 475, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Test #2277: Case Ih Steiger 425, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

On The Area-Averaged Effective Sound Absorption Coefficient Of Porous Materials Excited By A Monopole, Franck Sgard, Noureddine Atalla, Olivier Robin, Alain Berry

Études primaires

The area-averaged effective sound absorption coefficient (SAC) of a rigid-backed homogeneous porous material subjected to a monopole excitation is calculated as the absorbed-to-incident sound power ratio. Using Allard's model to describe the sound propagation above the porous material, an analytical model for this power-based SAC is proposed and proves to give a good approximation of the sound absorption performance under monopole excitation of sufficiently large areas of material. The impact of factors on the power-based SAC, such as monopole height, material radial dimension used to calculate the sound powers, and material properties is discussed. The power-based SAC frequency-dependent behavior is …

A Decision-Making Approach To Reduce The Risk Of Measurement Uncertainty For Product Size, Mostafa Awadalla Sedeek, Fatma Abdallah Elerian, Ossama Badie Abouelatta, Mona. A. Aboueleaz

Mansoura Engineering Journal

The measurement uncertainty has a significant impact on quality control processes. This is particularly true of standards that are assessed to determine if a product is compliant. This ambiguity introduces two potential risks of decision-making: accepting a non-conventional product (the consumer's risk) or rejecting a conventional product (the producer's risk). This investigation explores the potential for false decisions caused by measurement errors in product assessments. By studying data near the control limits, a greater understanding of the manufacturing process is intended to facilitate informed decision-making, and guide the implementation of effective quality control methods. The investigation highlights the importance of …

Minimizing The Production Cost Of The Cam-Follower Profile Using Shape Optimization Techniques, Khaled Ahmed, Magdy Samuel, Rania Mostafa

Mansoura Engineering Journal

The study of shape optimization techniques in structural products helps in reducing mechanical stresses and vibrations in related mechanical elements, such as cam follower mechanisms. This, in turn, has a positive impact on cost savings in the manufacturing process and enhances production quality and reliability. The point of view in this research depends on the idea of minimizing the total production cost while ensuring good functional performance of the cam profile during the shape-manufacturing optimization problem-solving process. The investigation of the impact of changing the motion type of a cam, such as Uniform Velocity Motion (UVM) and Simple Harmonic Motion …

Porous Bearing Research Rig, Josh Beranek, Hannah Liggett, Jonathan Lemmon, Brandon Allen

Williams Honors College, Honors Research Projects

Our team has decided to continue the research of fluid bearings, specifically, that of the journal and porous bearing. This will continue off of research currently being done at the University of Akron by graduate student Elizabeth Clifford who has developed a mathematical model for a porous bearing. Our job will be to create a testing rig that will be able to either prove or disprove this model. To do this, the rig will need to be able to take measurements of temperature and pressure at key areas within the bearing. It will also need to be readily capable of …

Shape Inverse Prediction Of Magnetic Field-Actuated Soft Robots By Neural Network Machine Learning, Lineth J. Perez Monsalve

Theses and Dissertations

Soft robotics has drawn tremendous interest in recent years because the compliance and motion of soft robotics enable biocompatibility and versatility for many applications, such as human-machine interaction, wearable and assistive devices, and health monitoring. This study introduces a novel predictive modeling approach using neural networks for shape control of magnetic soft robots. The robots are made of silicone materials embedded with hard magnetic particles, which respond to the external magnetic field provided by a ring-type of permanent magnet. These robots, free from physical connections to external devices, i.e., non-tethered actuation, hold significant potential for applications in healthcare, such as …

Investigation Of Spalart-Allmaras Turbulence Model For Vortex Flows, Abigail Rayna Kerestes

Browse all Theses and Dissertations

Conventional turbulence models often predict behaviors opposite as to what is observed in flows subject to rotation. In this type of flow scenario, rotation typically induces turbulence suppression. To address this limitation, a modification to the Spalart Allmaras Model with Rotation Correction (SA-R) was proposed to enhance the original Spalart Allmaras Model’s sensitivity to rotation and curvature. To test the validity and accuracy of this modification, two cases were investigated. The first case involved an axisymmetric rotating pipe. A Reynolds Number of 37,000 was implemented and the initial and boundary conditions established by Zaets et. al. were utilized. Initially non-rotating, …

Development Of Novel Hydrogel Materials For Viscoelastically Accurate Brain Phantoms, Lila G. Schandler

Theses and Dissertations

Current methods such as concussion tests and Magnetic Resonance Imaging (MRI) scans only reveal structural damage post-injury. Creating an anatomically accurate model of the brain that mimics brain structure and viscoelastic properties will further allow medical professionals to analyze concussion events and create curated and personalized plans of recovery for a patient’s unique brain injury.

Values have been established for the necessary viscoelastic properties (time constants and elasticity) to mimic the native human brain tissue such as grey matter and white matter. The mechanical properties of the hydrogel are tunable by varying the concentration of Phytagel (PHY), a protein binding …

Assessment Of Surface Waviness In A Wire Arc Additive Manufacturing Process, Shammas Mahmood Shafi

Dissertations, Master's Theses and Master's Reports

Wire Arc Additive Manufacturing (WAAM) is increasingly recognized for its ability to produce metal components with high deposition rates and efficiency, particularly in the aerospace and automotive sectors. However, one significant challenge that WAAM faces is achieving surface quality that complies with industry standards, as well as creating geometries that closely resemble the initial design. A crucial factor contributing to this challenge is surface waviness, which is an inherent characteristic of the WAAM process. This waviness arises from the geometry of the weld beads and the overlap distance between them. It can adversely affect the fusion quality of successive layers, …

Data Driven And Machine Learning Based Modeling And Predictive Control Of Combustion At Reactivity Controlled Compression Ignition Engines, Behrouz Khoshbakht Irdmousa

Dissertations, Master's Theses and Master's Reports

Reactivity Controlled Compression Ignition (RCCI) engines operates has capacity to provide higher thermal efficiency, lower particular matter (PM), and lower oxides of nitrogen (NOx) emissions compared to conventional diesel combustion (CDC) operation. Achieving these benefits is difficult since real-time optimal control of RCCI engines is challenging during transient operation. To overcome these challenges, data-driven machine learning based control-oriented models are developed in this study. These models are developed based on Linear Parameter-Varying (LPV) modeling approach and input-output based Kernelized Canonical Correlation Analysis (KCCA) approach. The developed dynamic models are used to predict combustion timing (CA50), indicated mean effective pressure (IMEP), …

Analysis Of Variations In Flow-Independent Liquid Jet-In-Crossflow Injections, Michael Scott

Honors Undergraduate Theses

Liquid fuel injection is a critical mechanism for the deliverance of liquid fuel in contemporary aircraft propulsion combustion systems due to its outsized influence in providing optimal combustion conditions and improving overall aircraft efficiency and performance. Despite this, these liquid jet in crossflow (LJIC) systems are highly variable due to conditions in the jet and the surrounding airflow, leading to variability in performance behavior and inconsistency in fuel mixing and combustion efficiency. This has prompted the introduction of solid pintile obstructions of novel designs to provide a more flow-independent fuel injection scheme and decrease variability of the jet properties against …

Designing A Visual Control Framework Based On Feature Point Analysis To Guide Robots In Uncharted Areas, Isam Sadiq Rasham Al-Ghadhbawi

Al-Esraa University College Journal for Engineering Sciences

Image processing may be made more accurate and efficient with the use of optical processing technologies. In order to make better design judgments early in the package design process, visual packaging art simulation aims to swiftly develop realistic packaging effects. Conventional simulation techniques frequently yield findings that are neither realistic or detailed, and they also take a lot of time and human resources. Optical processing-based machine vision technology can fully utilize computer vision and image processing techniques to simulate package designs accurately and efficiently. This research proposes a foundation for machine vision technologies based on image optical processing. Real package …

Optimizing Transcranial Focused Ultrasound: Calibration, Neuro Navigation, And Bold Fmri Evidence Of Neuromodulation, Amilcar J. Malave

Dissertations and Theses

This thesis presents the development, calibration, and initial implementation of transcranial focused ultrasound (tFUS) for neuromodulation in a human study. The primary objectives were to design a system capable of delivering precise and safe ultrasound stimulation to targeted brain regions and to conduct preliminary trials to assess its effects on brain activity. A custom calibration device was developed to ensure accurate measurement of acoustic pressure, addressing challenges such as voltage alterations caused by changes in system impedance. Additionally, a neuro-navigation tool was created to facilitate precise targeting of the right subgenual anterior cingulate cortex (right sgACC), enabling accurate placement of …

On The Understanding Of The Coastal-Urban Nexus Of Weather, Air Quality And Energy, Harold Gamarro

Dissertations and Theses

Urban environments exhibit complex interactions between atmospheric processes, building energy consumption, and air quality, particularly during periods of seasonal extremes such as summer ozone peaks and winter heating. Accurate representation of these interactions in urban modeling is crucial for understanding and addressing air pollution and energy management challenges in cities. This research presents a comprehensive study that advances urban atmosphere simulations by integrating building energy dynamics, air quality, and robust multi-source observational evaluation. Leveraging the Weather Research and Forecasting (WRF) model, coupled with a multilayer building environment parameterization (BEP) and a building energy model (BEM), with an improved boundary layer …

Actuator Optimization And Control Of Pediatric Knee Exoskeleton For Community-Based Mobility Assistance: More Lightweight, More Affordable, And More Stable, Sainan Zhang

Dissertations and Theses

Lightweight and smart exoskeletons offer the potential to improve mobility in children. State-of-the-art pediatric exoskeletons are typically clinic-based since they are either tethered or portable but cumbersome, and their design is often not optimized across a range of environments and users. Child growth progressively alters key exoskeleton design requirements, yet no prior work investigated actuator optimization to accommodate child growth. Moreover, exoskeletons typically use the torque sensor or spring mechanics as exteroceptive feedback, but these torque sensing methods not only lead to extra cost and mass but also cause a small range of stable controller gains.

To facilitate pediatric exoskeleton …

Hybrid Triboelectric-Piezoelectric Nanogenerator For Long-Term Load Monitoring In Total Knee Replacements, Mahmood Chahari, Emre Salman, Ryan Willing, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

A self-powered and durable pressure sensor for large-scale pressure detection on the knee implant would be highly advantageous for designing long- lasting and reliable knee implants as well as obtaining information about knee function after the operation. The purpose of this study is to develop a robust energy harvester that can convert wide ranges of pressure to electricity to power a load sensor inside the knee implant. To efficiently convert loads to electricity, we design a cuboid-array-structured tribo-pizoelectric nanogenerator (TPENG) in vertical contact mode inside a knee implant package. The proposed TPENG is fabricated with aluminum and cuboid-patterned silicone rubber …

Me-Em Enewsbrief, December 2023, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Modeling And Performance Evaluation Of Traditional And Ai-Based Mppt Techniques For Photovoltaic Systems., Md Badruddaza

Graduate Research Theses & Dissertations

The efficiency levels to convert from sunlight to electricity are in the range up to 22% commercially, based on the technology used. Due to comparatively low efficiency of photovoltaic systems, it is imperative to extract maximum power from the PV module array. Thus, in solar PV system, tracking the module’s MPP (maximum power point) is crucial and at the same time challenging as well due to varying climatic conditions. This research focuses on the modeling and performance evaluation of traditional Maximum Power Point Tracking (MPPT) techniques and AI-Based MPPT algorithms in photovoltaic systems. It addresses the issue of dynamic adjustment …

Bidirectional In-Situ Analysis And Visualization Of Fluid Structure Interactions With Applications In Blood Flow, Nazariy Tishchenko

Graduate Research Theses & Dissertations

Interactive blood flow simulation has applications in the understanding of complex fluids,training medical professionals, diagnostics, and surgical procedure planning. Bidirectional in situ visualization and analysis are much needed to streamline the analysis of large-scale patient-specific blood flow simulations. The in situ component ensures the live visualization of the simulation results while the simulation is running, and the bidirectional component allows for real-time control and configuration of the simulation parameters (i.e., setting and retrieving the simulation parameters and data based on need). In this project, a highly accurate multiphysics simulation was instrumented to work with an existing bidirectional in situ framework. …

Simulation Of Reacting Supersonic Flow In A Cavity Flameholder, Mohamed Benjelloun Touimi

Electronic Theses and Dissertations

Scramjet engines, or Supersonic Combustion Ramjets, are pivotal for achieving and maintaining hypersonic flight speeds. These engines leverage the high-speed airflow to compress and mix air and fuel for combustion. A significant challenge in Scramjet engine design is ensuring stable and efficient combustion within this high-speed environment. Cavity flameholders are crucial components that stabilize the combustion process by creating a subsonic region where the fuel-air mixture can ignite and sustain combustion. This research simulates this supersonic flow within the combustion chamber to accurately model and analyze the combustion dynamics. Various turbulence models, including RANS, and DES, are evaluated for their …

Computational Characterization Of Extracellular Electro-Osmotic Flow During Tissue Repair, Ashley Jorgensen-Blocker

Electronic Theses and Dissertations

Electrical stimulation (ES) therapy promotes the healing of chronic epidermal wounds and suppresses the degeneration of articular cartilage. Despite the success of ES therapy, the underlying mechanisms by which ES promotes tissue repair are largely unknown, preventing the standardization and optimization of treatments. One proposed mechanism involves electro-osmotic flow (EOF), electrically driven water flow generated within close proximity to the cell surface. EOF induces the transport of macromolecules and removes metabolic wastes and inflammatory molecules from these dense tissues through interstitial flow. This dissertation investigates the application of weak electric fields (EFs) to non-excitable cells and the generation of EOF …

On The Use Of The Local Reflection Coefficient To Assess The Diffuse Field Sound Absorption Coefficient Of A Porous Material, Franck Sgard, Noureddine Atalla, Olivier Robin

Études primaires

The diffuse field sound absorption coefficient (SAC) of a sound absorber can be obtained from an average over the incidence angles of the oblique incidence plane wave SAC. The plane wave SAC can be derived from the plane wave complex-valued reflection coefficient defined as the ratio of the reflected sound pressure at a given point on the material surface to the incident sound pressure at the same point. In practice, the material is excited by a monopole, and the reflection coefficient becomes a local quantity which is a function of the source height and the radial distance from the source. …

Radiation Force Modeling For A Wave Energy Converter Array, Salman Husain, Gordon Parker, David Forehand, Enrico Anderlini

Michigan Tech Publications

The motivation and focus of this work is to generate passive transfer function matrices that model the radiation forces for an array of WECs. Multivariable control design is often based on linear time-invariant (LTI) systems such as state-space or transfer function matrix models. The intended use is for designing real-time control strategies where knowledge of the model’s poles and zeros is helpful. This work presents a passivity-based approach to estimate radiation force transfer functions that accurately replace the convolution operation in the Cummins equation while preserving the physical properties of the radiation function. A two-stage numerical optimization approach is used, …

Electrostatic Sorting Of Lunar Regolith Simulants For Sustainable Resource Utilization: Modeling And Characterization Of Particle Size Distribution, Abdullah Al Moinee, Peter Bachle, Kyle Newport, William Schonberg, David Bayless, Jeffrey Smith, Daoru Han, Fateme Rezaei

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In pursuit of sustainable resource utilization on the Moon, this paper delves into modeling and characterization of particle size distribution (PSD) of lunar regolith simulants in an electrostatic system. a prototype electrostatic sieve was built and tested with four sample simulants mirroring properties of lunar mare and highland regolith. an alternating four-phase (90 degrees, 180 degrees, 270 degrees, 360 degrees) traveling square-wave was utilized for particle-directed transport to model the diverse trajectories of the particles. Numerically, we scrutinized how the distribution functions of the particles are manifested as the electrostatic field propagates, with a focus on three distinct particle ranges …

A Novel Magnetorheological Pump Concept For Insulin Delivery, Mohammad Towhidul Islam Rimon

College of Graduate Studies: Theses & Dissertations

Over the past 25 years, awareness of type 1 diabetes has significantly increased, leading to a comprehensive understanding of various aspects, including its genetics, epidemiology, and disease burden. According to the Type 1 Diabetic Index, about 8.7 million people around the world live with this long-term autoimmune disease characterized by insulin deficiency and resultant hyperglycemia. However, the increased availability and utilization of artificial pancreas systems could potentially save 673,000 lives by 2040. Although, the advancement of diabetes technology offers Type 1 diabetic patients more tools to enhance glycemic management and achieve effective outcomes, many patients are still hesitant to adopt …

Railroad Condition Monitoring Using Distributed Acoustic Sensing And Deep Learning Techniques, Md Arifur Rahman

College of Graduate Studies: Theses & Dissertations

Proper condition monitoring has been a major issue among railroad administrations since it might cause catastrophic dilemmas that lead to fatalities or damage to the infrastructure. Although various aspects of train safety have been conducted by scholars, in-motion monitoring detection of defect occurrence, cause, and severity is still a big concern. Hence extensive studies are still required to enhance the accuracy of inspection methods for railroad condition monitoring (CM). Distributed acoustic sensing (DAS) has been recognized as a promising method because of its sensing capabilities over long distances and for massive structures. As DAS produces large datasets, algorithms for precise …

Impact Of Operational Conditions On The Transient Thermal Behavior Of Lithium-Ion Batteries, Jairo Sebastian Casa

College of Graduate Studies: Theses & Dissertations

Considering the high increase of lithium-ion batteries (LIBs) through the years, it is important to analyze the impact of the operational conditions, such as charging and discharging on the transient thermal behavior of LIBs for thermal management of Li-Ion batteries. A pseudo two-dimensional mathematical model based on the finite volume method (Doyle-Fuller Newman) available in an open-source environment such as Python, was utilized for the electrochemical evaluation of the Li-Ion battery. For simplicity, a lumped thermal model was integrated with the electrochemistry model to evaluate the transient behavior of Li-Ion cells under varying conditions. Both the electrochemistry and lumped thermal …

Stability Analysis Of Vertical Industrial Pressure Vessel Resting On Load Cells Subjected To A Seismic Load., Kameron W. Nez

College of Graduate Studies: Theses & Dissertations

Instability of structures, such as large vertical pressure vessels, is always an issue under the seismic load. In this current work, the acceleration that causes instability for a vertical pressure vessel has been determined experimentally using scaled models. This instability is caused by the tipping of the tall structure that is not completely fixed to the ground. This method is applied for three different sizes of pressure vessels, representing 50 CuFt to 1100 CuFt full scale models. These experimental results are compared with theoretical models. Using dimensional analysis, the accelerations that will cause the instability in the actual full-size models …