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Utilizing Bayesian Optimization In Technoeconomic Analyses For Integrated Energy Systems, Anthoney Griffith Aug 2024

Utilizing Bayesian Optimization In Technoeconomic Analyses For Integrated Energy Systems, Anthoney Griffith

All Graduate Theses and Dissertations, Fall 2023 to Present

Technoeconomic analysis is a key element in the study of integrated energy systems. The goal of this analysis is the sizing of technologies resulting in the best economic outcome for the system. The evaluation of this system involves sizing the components and simulating the resulting market to determine an outcome. This simulation incorporates multiple possible values of uncertain parameters like grid price and wind generation. This problem is currently approached with the gradient descent optimization method. An alternative approach, Bayesian optimization, sees success on simple problems of a similar nature to technoeconomic analyses. These results motivate applying Bayesian optimization as …


Techniques To Overcome Energy Storage Limitations In Electric Vehicles, Matthew J. Hansen May 2024

Techniques To Overcome Energy Storage Limitations In Electric Vehicles, Matthew J. Hansen

All Graduate Theses and Dissertations, Fall 2023 to Present

Electric vehicles are becoming increasingly popular, battery limitations (cost, size, and weight) complicate electric vehicle adoption. While important research on battery development is ongoing, this dissertation discusses two main approaches to overcome those limitations within the existing battery technology paradigm. Those thrusts are: improving battery health through an optimal charging strategy and minimizing necessary battery size through dynamic wireless power transfer. In this dissertation, relevant literature is discussed, with opportunities for further development considered. Within the two thrusts, three objectives sharpen the focus of the research presented here. First, a planning tool is defined for a battery electric bus fleet. …


Cost Minimizing Energy Management Control Scheme For Microgrids Considering Dynamic Electricity Prices, Levi T. Miller Dec 2023

Cost Minimizing Energy Management Control Scheme For Microgrids Considering Dynamic Electricity Prices, Levi T. Miller

All Graduate Theses and Dissertations, Fall 2023 to Present

As countries develop and technology improves, the world is using more energy than ever before. This fact along with several other political, social, and economic factors has resulted in simultaneous energy and climate crises. A partial solution to both problems is bringing clean energy sources of electricity closer to the customers who use that energy. A microgrid is a smaller version of the national electric grid where smaller electricity generators are networked with local consumers and controlled independently of the main grid. Because control of electricity sources and loads are transferred to local controllers, the flexibility with which they can …


Multi-Fidelity Predictions For Control Allocation On The Nasa Ikhana Research Aircraft To Minimize Drag, Justice T. Schoenfeld Dec 2022

Multi-Fidelity Predictions For Control Allocation On The Nasa Ikhana Research Aircraft To Minimize Drag, Justice T. Schoenfeld

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Optimal control settings (camber scheduling) can be used by aircraft to minimize drag at various operating conditions during flight. In this work, camber schedules for minimum drag on the NASA Ikhana are obtained over a range of lift coefficients. A modern numerical lifting-line algorithm is used to predict the lift and drag of the aircraft as a function of operating condition and wing section shape (airfoil camber). The SLSQP optimization algorithm is used to solve for the camber schedule that minimizes drag for a given operating condition. The process is repeated, varying the number of control sections to evaluate the …


Control Mapping Methodology For Tailless Morphing-Wing Aircraft, Zachary S. Montgomery Aug 2022

Control Mapping Methodology For Tailless Morphing-Wing Aircraft, Zachary S. Montgomery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Advanced aircraft designs tend to have several control surfaces or devices that affect the flight of the aircraft. It is difficult or even impossible for a pilot to directly control each of these devices and fly the aircraft well. Therefore, a control mapping logic is needed to take typical pilot commands and map them to what the control devices should do to achieve the pilot’s commands. This work presents a methodology for determining this control mapping logic using two different approaches. The first uses a theoretical approach based on lifting-line theory, while the second leverages computational methods. The methodology consists …


Optimal Relative Path Planning For Constrained Stochastic Space Systems, Nathan Bohus Stastny May 2022

Optimal Relative Path Planning For Constrained Stochastic Space Systems, Nathan Bohus Stastny

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rendezvous and proximity operations for automated spacecraft systems requires advanced path planning techniques that are capable of generating optimal paths. Real-world constraints, such as sensor noise and actuator errors, complicate the planning process. Operations also require flight safety considerations in order to prevent the spacecraft from potentially colliding with the associated companion spacecraft. This work proposes a new, ground-based trajectory planning approach that seeks an optimal trajectory while meeting all mission constraints and accounting for vehicle performance and safety requirements. This approach uses a closed-loop linear covariance simulation of the relative trajectory coupled with a genetic algorithm to determine fuel …


Surrogate Optimization Model For An Integrated Regenerative Methanol Transcritical Cycle, Yili Zhang Aug 2021

Surrogate Optimization Model For An Integrated Regenerative Methanol Transcritical Cycle, Yili Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to reduce the cost ($) per megawatts hour (MWh) of electrical energy generated by a nuclear power cycle with a novel small modular reactor (SMR), a new SMR-based nuclear power cycle with Methanol as working fluid was designed. It was built virtually with the Python & Coolprop software based on all components’ physical properties, and it is therefore called the physics-based model. The physics-based model would require seven user-defined values as input for the seven free design parameters, respectively. The physics-based model outcomes include LCOE (the cost per megawatts hour of electrical energy generated by the …


Sonic Boom Loudness Reduction Through Localized Supersonic Aircraft Equivalent-Area Changes, Troy A. Abraham May 2021

Sonic Boom Loudness Reduction Through Localized Supersonic Aircraft Equivalent-Area Changes, Troy A. Abraham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The NASA University Leadership Initiative (ULI) titled “Adaptive Aerostructures for Revolutionary Civil Supersonic Transportation” looks to study the feasibility of distributed structural adaptivity on a supersonic aircraft for maintaining acceptable en-route sonic boom loudness during overland flight. The ULI includes a team of industry and university partners that are working together to develop and implement the systems necessary to accomplish this goal.

The Utah State University Aerolab is a member of this ULI team and has been tasked with developing and using low-fidelity supersonic aerodynamic and sonic boom predictions tools to rapidly study the effects of localized geometry changes on …


Optimization Of Aileron Spanwise Size And Shape To Minimize Induced Drag In Roll With Correlating Adverse Yaw, Joshua R. Brincklow Aug 2020

Optimization Of Aileron Spanwise Size And Shape To Minimize Induced Drag In Roll With Correlating Adverse Yaw, Joshua R. Brincklow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Most modern aircraft make use of modifying the main wing in flight to begin a roll. In many cases, this is done with a discrete control surface known as an aileron. The lift, drag, and moments for the wing are affected in part by the location and size of the ailerons along the length of the wing. The lift, drag, and moments can be found using a lifting-line theory that considers the circulation in airflow from many small sections of the wing. To minimize the drag due to lift on the wing, the ailerons must be optimized for the best …


Numerical Method For Rapid Aerostructural Design And Optimization, Jeffrey D. Taylor, Douglas F. Hunsaker Jun 2020

Numerical Method For Rapid Aerostructural Design And Optimization, Jeffrey D. Taylor, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

During early phases of wing design, analytic and low-fidelity methods are often used to identify promising design concepts. In many cases, solutions obtained using these methods provide intuition about the design space that is not easily obtained using higher-fidelity methods. This is especially true for aerostructural design. However, many analytic and low-fidelity aerostructural solutions are limited in application to wings with specific planforms and weight distributions. Here, a numerical method for minimizing induced drag with structural constraints is presented that uses approximations that apply to wings with arbitrary planforms and weight distributions. The method is applied to the NASA Ikhana …


Nonpoint Source Pollution Control Using A Multi-Objective Optimization Tool For Best Management Practices Selection And Spatial Placement In The Lower Bear River Watershed, Utah, Ali A. Salha May 2020

Nonpoint Source Pollution Control Using A Multi-Objective Optimization Tool For Best Management Practices Selection And Spatial Placement In The Lower Bear River Watershed, Utah, Ali A. Salha

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation presents a set of approaches to help address water quality problems related to total phosphorus loads in water bodies. Water quality degradation is caused by many nonpoint sources such as agricultural runoff, fertilizers applications, and bank erosion. Three studies present methodologies for water quality protection from degradation in watersheds. The first study demonstrates the application of a watershed simulation tool that can quantify flows in the watershed, the amount of released pollutants and identify the areas contributing to the pollutants’ release in the watershed. The second study presents a simple combination tool that can pair potential management practices …


An Efficient Process For Co-Production Of Γ-Aminobutyric Acid And Probiotic Bacillus Subtilis Cells, Hongbo Wang, Jinge Huang, Lei Sun, Fuchao Xu, Wei Zhang, Jixun Zhan Sep 2018

An Efficient Process For Co-Production Of Γ-Aminobutyric Acid And Probiotic Bacillus Subtilis Cells, Hongbo Wang, Jinge Huang, Lei Sun, Fuchao Xu, Wei Zhang, Jixun Zhan

Biological Engineering Faculty Publications

This study was to establish an integrated process for the co-production of γ-aminobutyric acid (GABA) and live probiotics. Six probiotic bacteria were screened and Bacillus subtilis ATCC 6051 showed the highest GABA-producing capacity. The optimal temperature and initial pH value for GABA production in B. subtilis were found to be 30 °C and 8.0, respectively. A variety of carbon and nitrogen sources were tested, and potato starch and peptone were the preferred carbon and nitrogen sources for GABA production, respectively. The concentrations of carbon source, nitrogen source and substrate (sodium L-glutamate) were then optimized using the response surface methodology. The …


Chaotic Phase-Coded Waveforms With Space-Time Complementary Coding For Mimo Radar Applications, Sheng Hong, Fuhui Zhou, Yantao Dong, Zhixin Zhao, Yuhao Wang, Maosong Yan Jul 2018

Chaotic Phase-Coded Waveforms With Space-Time Complementary Coding For Mimo Radar Applications, Sheng Hong, Fuhui Zhou, Yantao Dong, Zhixin Zhao, Yuhao Wang, Maosong Yan

Electrical and Computer Engineering Faculty Publications

A framework for designing orthogonal chaotic phase-coded waveforms with space-time complementary coding (STCC) is proposed for multiple-input multiple-output (MIMO) radar applications. The phase-coded waveform set to be transmitted is generated with an arbitrary family size and an arbitrary code length by using chaotic sequences. Due to the properties of chaos, this chaotic waveform set has many advantages in performance, such as anti-interference and low probability of intercept. However, it cannot be directly exploited due to the high range sidelobes, mutual interferences, and Doppler intolerance. In order to widely implement it in practice, we optimize the chaotic phase-coded waveform set from …


Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor May 2018

Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The design of an aircraft wing often involves the use of mathematical methods for simultaneous aerodynamic and structural design. The goal of many of these methods is to minimize the drag on the wing. A variety of computer models exist for this purpose, but some require the use of expensive time and computational resources to give meaningful results. As an alternative, some mathematical methods have been developed that give reason ably accurate results without the need for a computer. However, most of these methods can only be used for wings with specific shapes and payload distributions. In this thesis, a …


Water Resources Adaptation To Climate And Demand Change In The Potomac River, James H. Stagge, Glenn E. Moglen Sep 2017

Water Resources Adaptation To Climate And Demand Change In The Potomac River, James H. Stagge, Glenn E. Moglen

Publications

The effects of climate change are increasingly considered in conjunction with changes in water demand and reservoir sedimentation in forecasts of water supply vulnerability. Here, the relative effects of these factors are evaluated for the Washington, DC metropolitan area water supply for the near (2010 to 2039), intermediate (2040-2069), and distant future (2070 to 2099) by repeated water resources model simulations. This system poses water management challenges due to long water delivery travel times that increase uncertainty, multiple water jurisdictions that constrain potential decisions, and future scenarios that simultaneously increase demand and decrease water supply during the critical summer period. …


Maximum Likelihood Temperature/Emissivity Separation Of Hyperspectral Images With Gaussian Distributed Downwelling Radiance, David A. Neal May 2017

Maximum Likelihood Temperature/Emissivity Separation Of Hyperspectral Images With Gaussian Distributed Downwelling Radiance, David A. Neal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hyperspectral images are made up of energy measurements at different wavelengths of light. The case is considered where these measurements are dependent on temperature, the self-emitted energy (emissivity), and reflected energy (downwelling radiance) from the surroundings. The process where the downwelling radiance is fixed and the temperature and emissivity are estimated is referred to as temperature/emissivity separation.

Due to the way these terms mix, for a given set of measurements, there exist many pairs of temperatures and emissivities that satisfy the model. This creates ambiguity in the solution that must be resolved for the result to have any significance.

A …


Introduction To Water Resources Systems - University Of Colorado Boulder, Joseph Kasprzyk Jan 2017

Introduction To Water Resources Systems - University Of Colorado Boulder, Joseph Kasprzyk

All ECSTATIC Materials

This is the introductory lecture to a Water Resource Systems and Management class from Spring 2017 at the University of Colorado Boulder, by Joseph Kasprzyk. Learning goals include (i) defining integrated water resources management, (ii) identifying Colorado water management issues (ii) identifying how RiverWare simulation and optimization can be used to develop water plans (iii) use the HyMod model to perform rainfall-runoff modeling (iv) generating random parameter samples and understanding how parameter uncertainty affects model results.


Optimizing Dam Siting In The Paru River In Brazil Using A Multi-Objective Approach, Henrique De Paula May 2016

Optimizing Dam Siting In The Paru River In Brazil Using A Multi-Objective Approach, Henrique De Paula

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

How should a decision-maker choose which hydropower plant to build in a given river? Hydropower plant expansion is a task that involves several stakeholders, objectives, and resources. It requires that decision-makers use not only experience and previous knowledge to come up with their final decision, but also the use of tools to help them to decide, as well as to support their choices. The present project developed a computation model to optimize the choice of hydropower plants that can be built within a given river, considering three different objectives - energy generation, flooded surface area and river connectivity. The input …


Optimizing Sustainable Integrated Use Of Groundwater, Surface Water And Reclaimed Water For The Competing Demands Of Agricultural Net Return And Urban Population, Silvia Anastasia Landa May 2016

Optimizing Sustainable Integrated Use Of Groundwater, Surface Water And Reclaimed Water For The Competing Demands Of Agricultural Net Return And Urban Population, Silvia Anastasia Landa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The world population is growing rapidly. In developing countries, the growing population is mostly in urban areas. A bigger population requires more food, and more food requires more water. The water needed for food and people comes from the same sources: surface water (rivers, lakes, etc.) and groundwater (aquifers). Thus, there is a competing water demand between people and agriculture in urban areas.

In this research, we use computer software to make a model of the hydrologic system that focuses on surface water and groundwater. To make the model, we use data from real aquifers and streams in order to …


Process Optimization To Enhance Quality And Quantity Of Transiently Expressed Proteins | Biological Engineering, Usu College Of Engineering Oct 2015

Process Optimization To Enhance Quality And Quantity Of Transiently Expressed Proteins | Biological Engineering, Usu College Of Engineering

College of Engineering News

Transient transfection is a method to introduce foreign DNA into a healthy cell population. Transient transfection can be accomplished by chemical, mechanical, and electrical delivery. Although foreign DNA is not incorporated into the host cell genome, host cell machinery is used to transcribe and translate the gene of interest. This presentation will illustrate the enhancement of transgene production through reagent optimization and feeds and show benefits of transient work, such as, eliminating the need for generation of a stable engineered cell line; allowing the process scaleability; and decreasing the time for generation of comparable amounts of product.


Engineering Optimization: Methods/Applications - Colorado State University, John Labadie Oct 2015

Engineering Optimization: Methods/Applications - Colorado State University, John Labadie

All ECSTATIC Materials

This course provides a comprehensive treatment of methods of optimization with focus on linear programming and its extensions, network flow optimization, integer programming, quadratic programming, and an introduction to nonlinear programming. The goal is to maintain a balance between theory, numerical computation, problem setup for solution by computer algorithms, and engineering applications. Course taught at Colorado State University.


Environmental Systems Analysis - Hong Kong University Of Science And Technology, Hong Kong, Ng Tze Ling Oct 2015

Environmental Systems Analysis - Hong Kong University Of Science And Technology, Hong Kong, Ng Tze Ling

All ECSTATIC Materials

Undergraduate course in environmental systems analysis offered at Hong Kong University of Science and Technology, Hong Kong in Fall 2015.


Water Resources Systems Analysis - University Of Texas San Antonio, Marcio Giacomoni Oct 2015

Water Resources Systems Analysis - University Of Texas San Antonio, Marcio Giacomoni

All ECSTATIC Materials

Systems Analysis methods use algorithmic and mathematical approaches for problem-solving. These are powerful methods that can be applied to solve complex design and management problems for water resources systems and other engineering areas. This class will focus on optimization methods, such as linear programming, integer programming, nonlinear programming, genetic algorithms, and dynamic programming, and their application to water resources systems. Advanced Systems Analysis methods, including sensitivity analysis, alternatives generation, and multi-objective optimization will be introduced to address the complexities associated with public sector decision-making. Course taught at University of Texas San Antonio.


Optimization And Control Of Lumped Transmitting Coil-Based In-Motion Wireless Power Transfer Systems, Nazmul Hasan May 2015

Optimization And Control Of Lumped Transmitting Coil-Based In-Motion Wireless Power Transfer Systems, Nazmul Hasan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis explores optimization and control aspects of in-motion electric vehicle charging. The vision is of an electrified roadway, where the vehicles can move and charge at the same time. The present systems have long tracks embedded in the roadway which transfer energy. This thesis explores smaller coils in the road, which has the promise of higher efficiency and lower volt ampere ratings. The promise can only be realized through optimized design and synchronized control of charging with respect to vehicle position. The existing design procedures lack comprehensiveness, require designer experience and use computationally costly 3D FEM algorithms. The proposed …


Water Resources Systems Analysis - Colorado State University, Darrell Fontane Apr 2015

Water Resources Systems Analysis - Colorado State University, Darrell Fontane

All ECSTATIC Materials

Applications of systems analysis, simulation and optimization techniques in water resources planning and management. Course taught at Colorado State University.


Environmental Systems Modeling And Management - University Of Virginia, Charlottesville, Teresa Culver Oct 2013

Environmental Systems Modeling And Management - University Of Virginia, Charlottesville, Teresa Culver

All ECSTATIC Materials

Grad/Undergrad course in environmental systems modeling and management offered at University of Virginia, Charlottesville in Fall 2013.


Deterministic Optimization And Design - University Of California, Davis, Jay R. Lund Oct 2013

Deterministic Optimization And Design - University Of California, Davis, Jay R. Lund

All ECSTATIC Materials

Undergraduate course in deterministic optimization and design offered at U.C. Davis.


Decomposed Lifting-Line Predictions And Optimization For Propulsive Efficiency Of Flapping Wings, W. F. Phillips, R. A. Miller, Doug F. Hunsaker Jun 2013

Decomposed Lifting-Line Predictions And Optimization For Propulsive Efficiency Of Flapping Wings, W. F. Phillips, R. A. Miller, Doug F. Hunsaker

Mechanical and Aerospace Engineering Faculty Publications

A decomposed Fourier series solution to Prandtl's classical lifting-line theory is used to predict the lift, induced-thrust, and power coefficients developed by a flapping wing. A significant advantage of this quasi-steady analytical solution over commonly used numerical methods is the utility provided for optimizing wing flapping cycles. The analytical solution involves five time-dependent functions that could all be optimized to maximize thrust, propulsive efficiency, and/or other performance measures. Results show that by optimizing only two of these five functions, propulsive efficiencies exceeding 97% can be obtained. Results are presented for untwisted rectangular wings in pure plunging, rectangular wings with linear …


Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox Jan 2013

Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox

Undergraduate Honors Capstone Projects

Team Hot Stuff designed a thermal capacitor for Senior Design I at Utah State University. This thermal capacitor is intended for use in the food service industry as a low-cost alternative to chafers. Chafers are platters which use oil burners to keep food warm. The client for this thermal capacitor is Thermal Management Technologies (TMT), a company specializing in thermal science solutions whose mission is “to provide simple, practical thermal science solutions to a wide range of platforms including: Industry, Defense, and Space”1. The founder and president of TMT, Dr. J. Clair Batty, serves as a mentor for …


Ammonia Measurements And Emissions From A California Dairy Using Point And Remote Sensors, Kori D. Moore, E. Young, C. Gurell, Michael D. Wojcik, Randy S. Martin, G. E. Bingham, R. L. Pfeiffer, J. H. Prueger, J. L. Hatfield Dec 2012

Ammonia Measurements And Emissions From A California Dairy Using Point And Remote Sensors, Kori D. Moore, E. Young, C. Gurell, Michael D. Wojcik, Randy S. Martin, G. E. Bingham, R. L. Pfeiffer, J. H. Prueger, J. L. Hatfield

Civil and Environmental Engineering Faculty Publications

Ammonia (NH3) is an important trace gas species in the atmosphere that can have negative impacts on human, animal, and ecosystem health. Agriculture has been identified as the largest source of NH3, specifically livestock operations. NH3 emissions from a commercial dairy in California were investigated during June 2008. Cattle were held in open-lot pens, except for young calves in hutches with shelters. Solid manure was stored in the open-lot pens. Liquid manure from feed lanes was passed through a solids settling basin and stored in a holding pond. Passive sensors and open-path Fourier transform infrared spectrometers (OP-FTIR) were deployed around …