Engineering Commons^™

Modeling Of Amine-Based Co2 Capture Process, Zafar Safarovich Turakulov

Chemical Technology, Control and Management

A significant factor influencing climate change is the release of carbon dioxide (CO₂) into the atmosphere as a consequence of human activities such as the combustion of fossil fuels. Climate change can be slowed down by taking action to mitigate industrial-scale CO₂ emissions. Currently, the most advanced technology for capturing CO₂ from industrial flue gases is the post-combustion CO₂ capture based on amine absorption. However, due to the high energy penalties of existing CO₂ capture technologies and insufficient carbon markets, it is necessary to develop methods that compete with these technologies or minimize their …

Does Drought Stress Eliminate The Benefit Of Elevated Co2,/Sub> On Soybean Yield? Using An Improved Model To Link Crop And Soil Water Relations, Wenguang Sun, David Fleisher, Dennis Timlin, Chittaranjan Ray, Zhuangji Wang, Sahila Beegum, Vangimalla Reddy

Daugherty Water for Food Global Institute: Faculty Publications

Crop simulation models are indispensable tools that facilitate studies to assess climate impacts and adaptation responses, but have not been adequately tested in terms of accurately predicting crop growth and water stress responses to high carbon dioxide concentrations [CO₂]. The soybean model, GLYCIM, previously modified with a coupled leaf-level gas exchange – energy balance model, was integrated with a two-dimensional convectivediffusive root growth module which linked soil and leaf water potentials with the regulation of stomatal conductance. We evaluated the accuracy of this modified GLYCIM using experimental data from a Free-Air CO₂ Enrichment (FACE) site, SoyFACE, and …

Development And Evaluation Of A Teaching Concept That Focuses On Increasing Modeling Competence In Technical Mechanics (Tm), Kristina Lampe, Martin Lang, Alexandra Dorschu

Research Papers

Engineering students often learn by retracing pre-calculated given solutions of tasks and try to understand this problem-solving way. This reconstruction is not always successful in solving new types of problem via modified tasks (Rossow 2008). Every mechanical exercise follows the same solution methodology (Müller-Slany 2018). Applying this basic problem-solving structure correctly is a Pre-condition for solution’s reflection and is therefore essential for teaching. To improve these competencies a strategy training is implemented in exercise-settings in Technical Mechanics (TM).

A Globalized Optimization Schema For Automated Fiber Placement Processing Parameters, Matthew John Godbold

Theses and Dissertations

Automated Fiber Placement is an advanced manufacturing technique for industrial-scale composite structures. Advanced robotics coupled with composite manufacturing results in faster and more consistent results than previously obtained through hand layup. The complexity and interconnectedness of the automated fiber placement process provides a difficult challenge for traditional modeling techniques. Modeling within automated fiber placement currently utilizes physics-based modeling to inform the translation of a design to a manufacturing plan. The intricacy of the automated fiber placement process dictates that attempts at modeling or optimizing these processes are often limited in their scope. Physics-based modeling for manufacturing typically involves numerous interacting …

Numerical Evaluation Of Forces Affecting Particle Motion In Time-Invariant Pressurized Jet Flow, Donald E. Peterson

Theses and Dissertations

This work evaluates the relative significance of forces determining the motion of a pulverized coal particle under conditions representative of a pressurized oxy-coal combustor. The gravity force and surface forces of drag, fluid stress, added mass, and Basset history are discussed and appropriate forms of these force equations are chosen, with a consideration of spherical and non-spherical drag and the Basset history kernel. Studies from the literature that emphasize specific forces are used to validate the implementation of the force equations and correlations. Modeling is based on time-averaged, one-dimensional motion of a single non-reacting particle along the centerline of a …

Finite Element Modeling Of Patient-Specific Total Shoulder Arthroplasty, Ignacio Rivero Crespo

Electronic Theses and Dissertations

Total Shoulder Arthroplasty (TSA) is a surgical procedure designed to improve joint functionality by replacing the articulation between the humeral head and the glenoid fossa. Anatomic Total Shoulder Arthroplasty (aTSA) and Reverse Total Shoulder Arthroplasty (rTSA) are two types of replacement surgery to relieve pain and restore function of the shoulder. The overall goal of this study was to evaluate the effects of variation of certain patient and implant alignment parameters that may influence long-term outcomes of these surgical procedures, including kinematics, joint loads and contact mechanics. Computational models of six TSA subjects, three aTSA and three rTSA, were created …

Multiphysics Diesel Aftertreatment System Modeling For Reduced Emissions From Hybrid Electric Heavy-Duty Powertrains, Uday Srivastav

All Theses

Hybridization of heavy-duty on-road vehicles presents an opportunity to significantly reduce internal combustion engine emissions in real-world operation. These gains can be realized through the coordination of the electric drive, engine, and aftertreatment systems. Accurate Multiphysics models of all powertrains sub-systems are required to achieve the goal of reduced emissions. This research aims to develop a model of a highly complex diesel engine aftertreatment system. This study focuses on utilizing transient data for calibration and validation of the aftertreatment system and reducing the run time when compared to real-time experiments. The calibration focuses on two physical phenomena, thermal behavior and …

Multiscale Modeling And Gaussian Process Regression For Applications In Composite Materials, Joshua Arp

All Dissertations

An ongoing challenge in advanced materials design is the development of accurate multiscale models that consider uncertainty while establishing a link between knowledge or information about constituent materials to overall composite properties. Successful models can accurately predict composite properties, reducing the high financial and labor costs associated with experimental determination and accelerating material innovation. Whereas early pioneers in micromechanics developed simplistic theoretical models to map these relationships, modern advances in computer technology have enabled detailed simulators capable of accurately predicting complex and multiscale phenomena.

This work advances domain knowledge via two means: firstly, through the development of high-fidelity, physics-based finite …

Modeling And Dynamic Correction Of The Thermal Radiation Fluxes Measuring System, Olexander Alekseevich Sytnik, Fatima Mirazizovna Sagatova

Chemical Technology, Control and Management

Temperature measurements are currently an integral part of modern production, in particular, energy, aviation, instrumentation, etc. Therefore, the need to improve the accuracy of measurement, control and regulation of temperature largely determines the technical and economic efficiency of production. The development of reliable methods for temperature control under various conditions and the creation of specific devices is one of the most important tasks of modern instrumentation. The article deals with the issues of solving the problems of modeling and correcting the dynamic characteristics of a system for measuring thermal radiation fluxes using the integral method of signal recovery. For computer …

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 …

Model-Driven Analysis Of Ecg Using Reinforcement Learning, Christian O'Reilly, Sai Durga Rithvik Oruganti, Deepa Tilwani, Jessica Bradshaw

Publications

Modeling is essential to better understand the generative mechanisms responsible for experimental observations gathered from complex systems. In this work, we are using such an approach to analyze the electrocardiogram (ECG). We present a systematic framework to decompose ECG signals into sums of overlapping lognormal components. We use reinforcement learning to train a deep neural network to estimate the modeling parameters from an ECG recorded in babies from 1 to 24 months of age. We demonstrate this model-driven approach by showing how the extracted parameters vary with age. From the 751,510 PQRST complexes modeled, 82.7% provided a signal-to-noise ratio that …

Refactoring Dependency Loading And Standardizing Factory Patterns In The Horizon Simulation Framework, Jack W. Kelly

Master's Theses

The Horizon Simulation Framework (HSF) is an open-source community driven mod- eling and simulation tool developed over 15 years by a lineage of Cal Poly graduate students. The tool excels in its flexibility to model an assortment of complex systems, with prebuilt modeling elements available for the simulation of space missions. A high-level simulation tool like HSF lends itself to an agile development cycle as system constraints can be quickly identified through day in the life simulation of the modeled system. The objective of the work presented in this thesis is to refactor the way in which several modeling elements …

The Influence Of Heat And Mass Transfer On The Setting Rate Of Adhesives Between Porous Substrates, Mubarak Mohammed Khlewee

Electronic Theses and Dissertations

The dynamic penetration of fluid into a porous media where other changes are occurring such as temperature or concentration is of interest to a number of situations. However, little experimental and theoretical analysis of this situation is found in the literature where most of the previously published works have studied the penetration with constant physical properties, where there is no change of the fluid as it enters the pores. This situation is important in the setting of adhesives in porous medium such as in the setting of hot melt and water-based adhesives in the production of paper based packaging. The …

Nuclear Thermal Rocket Engine Instrumentation Addressing Environmental Limitations On Temperature Measurements, Dan C Floyd

Doctoral Dissertations

The development of nuclear thermal rockets has received renewed interest in recent years due to the benefits that can attained from this method of propulsion. Currently, instrumentation work is focused on the evaluation of current and near-term technology for implementation within a nuclear thermal rocket engine. One aspect of this evaluation is focused on the various instrumentation requirements of the system regarding necessary measurement parameters and environmental conditions for survivability. Historical nuclear rocket programs that have been conducted in the United States provide the basis for this information and indicates a critical need for high temperature measurement technology that can …

Comparing 1d, 2d, And 3d Hydraulic Models In Urban Flooding Applications, Taylor Kesler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Floods have been a hazard to people since people first started building near rivers. Predicting floods can be very beneficial to save lives and property. Computers have made it possible to solve fluid dynamics equations in a fast and efficient manner. Computer programs have been designed to solve these equations and create digital models of floods.

This study compares three different methods of computer modeling and explores their advantages and disadvantages. One-dimensional models solve fluid equations by setting up a series of cross sections. Two-dimensional models use a grid-like mesh to solve fluid equations from one cell to the next. …

Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, Chen Fang, Qusai Alomari, Daniel G. Linzell

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Highway bridges exposed to intentional or unintentional fire followed by combined vehicle impact and air blast are at risk of significant damage and, possibly, collapse. Limited studies examining the complex effects of these extreme demands on bridge support elements and parametrizing their response and damage are found in the open literature. Research that is presented is part of an ongoing numerical investigation examining round, multi-column, reinforced concrete (RC), bridge pier behavior subject to multi-hazard scenarios involving fire, vehicle impact, and air blast. Detailed nonlinear finite element analysis models of single columns and multi-column piers supported by a pile foundation system …

Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang

Electronic Theses and Dissertations

Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …

Opensim-Based Musculoskeletal Modeling: Foundation For Interactive Obstetric Simulator, Bahador Dodge

Electrical & Computer Engineering Theses & Dissertations

The use of mathematical and computational models to understand complex biological systems, such as the human birth process, is a rapidly growing field in medicine. These models can be used to optimize and personalize medical treatments for individual patients, enhance training, and aid in educational efforts. While recent advancements in healthcare, particularly in obstetrics, have improved care for mothers and babies, studies and government reports indicate a rising rate of maternal mortality in the United States.

Despite this rising trend, there is a lack of detailed studies concerning the use of modeling and simulation to develop an interactive obstetrics simulator …

Modeling And Adjustment Of A Fuzzy Controller In A Bioreactor Control System, Mahmudov Giyosjon Baqoyevich

Chemical Technology, Control and Management

The article describes the modeling and configuration of a fuzzy controller for the control system of the bacterial oxidation of hard-to-enrich gold-bearing sulfide ores. The simulated logical fuzzy controller allows you to save the consumption of refrigerant water consumed in the process by 4,3%, using it to control the process of bacterial oxidation.

Mathematical Description And Algorithm For Solving The Model Of The Ionite Regeneration Process In The Ion Exchange Method Of Water Softening, Djalolitdin Paxritdinovich Mukhitdinov, Nilufar Abdusami Qizi Yunusova

Chemical Technology, Control and Management

Based on the modern representation of the water softening process by the ion exchange method, modeling was carried out, an algorithm was developed and the ionite regeneration process was calculated in a water softening plant with a fixed ionite layer. To solve the system of equations of the model, special, but simple enough for use in engineering calculations, techniques and methods have been developed and applied. The constructed model and its solution algorithm can be used to predict the process of ionite regeneration in an ion exchange apparatus. It can also be used to calculate the time of the ionite …

Improving Future Vehicle Fuel Economy And Operational Design Domain Through Novel Data Pipelines, Kyle James Carow

Masters Theses

Modern automobiles have greatly advanced in recent years, with technological developments that enhance performance, safety, and comfort. However, there is still much room for improvement. Today’s vehicles are heavily reliant on the combustion of fossil fuels, proven to be harmful for the environment on both a local and global scale. In addition, the safety benefits of autonomous vehicles and advanced driver assistance systems are not yet fully realized due to the limited operational design domain of these technologies. In this research, these needs are addressed through the development of two novel data pipelines. In the first study, a novel methodology …

Comprehensive Process Planning Optimization Framework For Automated Fiber Placement, Alex Ryan Brasington

Theses and Dissertations

Advanced composite materials came about in 1966 and have since been widely used due to the possibility of superior structural performance while also achieving weight reductions. Such opportunities have led to composite materials being used to fabricate complex components, often in the aerospace sector. Most components, especially in aviation, are on a large scale and are outside the capabilities of traditional composite manufacturing techniques. Traditional manufacturing methods are also labor intensive, time consuming, have a high level of material scrap, and are prone to human error. This has led to the need for innovative manufacturing solutions to withstand the ever-increasing …

Modeling And Multi-Objective Optimization Of Wastewater Treatment Process, Navneet Kaur

Electronic Thesis and Dissertation Repository

Wastewater is water that has already been used and requires treatment before releasing it into natural water bodies like lakes and rivers. Wastewater treatment is the process of removing impurities from wastewater. In this treatment process, the impurities are removed and converted to effluent. This effluent is returned to the water cycle with minimum impact on the environment. Conventional treatment plants consist of three stages: primary, secondary, and tertiary treatment. Treatment of wastewater is quite complicated because of the number of stages involved in this process. Most wastewater treatment plants are operated manually therefore at times it becomes difficult for …

Characterization And Modeling Of Sparkless Discharge To A Touch Screen Display, Jianchi Zhou, Cheung Wei Lam, Zhekun Peng, Daryl G. Beetner, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Although Corona Discharge to a Touchscreen Display is Not Associated with the Spark, It Could Cause Soft and Hard Failures Due to Electromagnetic Coupling to Sensitive Electronics Beneath the Glass. Experimental Data Were Obtained to Characterize These Sparkless Discharges and an Equivalent Circuit Model Was Constructed to Predict the Resulting Coupling to Touchscreen Electronics. Measurements and Simulation Indicate that a Thinner Glass and a Higher Touchscreen Indium-Tin-Oxide (ITO) Sense Trace Impedance Both Lead to Higher ESD Risk by Delivering Higher Energy into the Sensing IC. a CST Co-Simulation Model is Proposed and is Shown to Model the Displacement Current Accurately. …

Securing The Transportation Of Tomorrow: Enabling Self-Healing Intelligent Transportation, Elanor Jackson, Sahra Sedigh Sarvestani

Electrical and Computer Engineering Faculty Research & Creative Works

The safety of autonomous vehicles relies on dependable and secure infrastructure for intelligent transportation. The doctoral research described in this paper aims to enable self-healing and survivability of the intelligent transportation systems required for autonomous vehicles (AV-ITS). The proposed approach is comprised of four major elements: qualitative and quantitative modeling of the AV-ITS, stochastic analysis to capture and quantify interdependencies, mitigation of disruptions, and validation of efficacy of the self-healing process. This paper describes the overall methodology and presents preliminary results, including an agent-based model for detection of and recovery from disruptions to the AV-ITS.

Modeling And Simulation Of A Process That Converts Ethane To Ethylene And Ethylene To Low Density Polyethylene, Ernest Bosire Mokaya

Graduate Theses, Dissertations, and Problem Reports

Ethylene is a critical feedstock and a major building block in the petrochemical industry that is used in synthesizing important products like polyethylene, ethanol, ethylene oxide, ethylene dichloride and ethylbenzene. With increasing demand of plastics, production of ethylene and subsequently polyethylene has increased globally. This thesis conducts the modeling and simulation of an integrated process that utilizes ethane as the primary feedstock to produce ethylene and the subsequent polymerization of ethylene to low-density polyethylene (LDPE). The process combines two different processes into one integrated process: (1) conversion of ethane to ethylene and (2) conversion of ethylene to LDPE. First, a …

Techno-Economic Analysis And Optimization Of Hydrogen And Mechanical Energy Storage Systems, Pavitra Senthamilselvan Sengalani

Graduate Theses, Dissertations, and Problem Reports

The increasing significance of renewable energy sources is thrusting the load cycling of fossil-fueled power plants (FFPP), designed to operate under nominal-load conditions. Integration of energy storage systems (ESS) with the FFPPs such as hydrogen energy storage (HES) and mechanical energy storage facility such as compressed air energy storage (CAES) shows the potential to minimize the levelized cost of electricity during high demand scenarios and also minimize the negative impacts of off-design FFPP operation. The deployment of energy storage facilities at the FFPP level have considerable potential advantages as they can be exploited within the existing equipment items and facilities …

Acausal Modeling Of Wind Turbines With Validation And Control Studies, Kazi Ishtiak Mohsin

Graduate Thesis and Dissertation 2023-2024

This thesis involves the modeling, validation, and control studies of a Control-Oriented, Reconfigurable, and Acausal Floating Turbine Simulator (CRAFTS), that is currently under development. CRAFTS uses Modelica®, an object-oriented, declarative, multi-domain modeling language for physical system modeling in the Dymola environment. The CRAFTS simulator facilitates rapid dynamic simulation of wind turbines with various model variants and enables control co-design.

A major emphasis of this thesis is in the validation of the CRAFTS simulator for a 15-MW land-based wind turbine through several test cases. These test cases were collaboratively developed in conjunction with other participating research entities. CRAFTS has undergone rigorous …

Magnetic Inversion Approach For Modeling Data Acquired Across Faults: Various Environmental Cases Studies, Khalid S. Essa, Eid R. Abo-Ezz, Neil Lennart Anderson, Omar A. Gomaa, Mahmoud Elhussein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

An effective extension to the particle swarm optimizer scheme has been developed to visualize and modelize robustly magnetic data acquired across vertical or dipping faults. This method can be applied to magnetic data sets that support various investigations, including mining, fault hazards assessment, and hydrocarbon exploration. The inversion algorithm is established depending on the second horizontal derivative technique and the particle swarm optimizer algorithm and was utilized for multi-source models. Herein, the inversion method is applied to three synthetic models (a dipping fault model contaminated without and with different Gaussian noises levels, a dipping fault model affected by regional anomaly, …

Final-Stage Densification Kinetics Of Direct Current–Sintered Zrb2, Austin D. Stanfield, Steven M. Smith, Suzana Filipović, Nina Obradović, Vladimir Buljak, Gregory E. Hilmas, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

Final-stage sintering was analyzed for nominally phase pure zirconium diboride synthesized by borothermal reduction of high-purity ZrO₂. Analysis was conducted on ZrB₂ ceramics with relative densities greater than 90% using the Nabarro–Herring stress–directed vacancy diffusion model. Temperatures of 1900°C or above and an applied uniaxial pressure of 50 MPa were required to fully densify ZrB₂ ceramics by direct current sintering. Ram travel data were collected and used to determine the relative density of the specimens during sintering. Specimens sintered between 1900 and 2100°C achieved relative densities greater than 97%, whereas specimens sintered below 1900°C failed to …