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Local Network Coding On Packet Erasure Channels -- From Shannon Capacity To Stability Region, Wei-Cheng Kuo
Local Network Coding On Packet Erasure Channels -- From Shannon Capacity To Stability Region, Wei-Cheng Kuo
Open Access Dissertations
Network Coding (NC) has emerged as a ubiquitous technique of communication networks and has extensive applications in both practical implementations and theoretical developments. While the Avalanche P2P file system from Microsoft, the MORE routing protocol, and the COPE coding architecture from MIT have implemented the idea of NC and exhibited promising performance improvements, a significant part of the success of NC stems from the continuing theoretic development of NC capacity, e.g., the Shannon capacity results for the single-flow multi-cast network and the packet erasure broadcast channel with feedback. However, characterizing the capacity for the practical wireless multi-flow network setting remains …
An Integrated System Of Vapor-Compression Chiller And Absorption Heat Pump: Experiment, Modeling, And Energy And Economic Evaluation, Yi-Shu Kung
Open Access Dissertations
Buildings currently consume 41% of the primary energy in the United States. Among the 41% primary energy, approximate 50% are used for building heating, cooling, and water heating. Improving the efficiencies of the devices for building heating and cooling has potentials to reducing the energy consumptions. This research aims to find one solution for building energy efficiency through investigating an Integrated System of an Integrated Compression-Absorption Subcooling System (ICASS) Based upon the principle of subcooling effect, the ICASS can improve the efficiency of the cooling device but also achieve additional useful heating sources potentially used for space heating and domestic …
Large Scale Modeling, Model Reduction And Control Design For A Real-Time Mechatronic System, Qiong Li
Large Scale Modeling, Model Reduction And Control Design For A Real-Time Mechatronic System, Qiong Li
Open Access Dissertations
Mechatronics is the synergistic integration of the techniques from mechanical engineering, electrical engineering and information technology, which influences each other mutually. As a multidisciplinary domain, mechatronics is more than mechanical or electronics, and the mechatronic systems are always composed of a number of subsystems with various controllers. From this point of view, a lot of such systems can be defined as large scale system. The key element of such systems is integration. Modeling of mechatronic system is a very important step in developing control design of such products, so as to simulate and analyze their dynamic responses for control design, …
Design Of Low-Thrust Missions To Asteroids With Analysis Of The Missed-Thrust Problem, Frank E. Laipert
Design Of Low-Thrust Missions To Asteroids With Analysis Of The Missed-Thrust Problem, Frank E. Laipert
Open Access Dissertations
Small bodies in the Solar System, such as asteroids and dwarf planets, are ideal targets for electric propulsion missions because of the high delta-V required to rendezvous with these targets. We study trajectories to the asteroid belt, including a human mission to Ceres and a sample return mission to (216) Kleopatra, along with trajectories to the Jupiter Trojan asteroids. For the human mission to Ceres, payload masses of 75 Mg are achievable with a 11.7 MW nuclear electric propulsion system and an initial mass in LEO of 289 Mg. For low-thrust sample return missions to the main belt asteroid Kleopatra, …
Computational Optical Imaging: Applications In Synthetic Aperture Imaging, Phase Retrieval, And Digital Holography, Dennis Joseph Lee
Computational Optical Imaging: Applications In Synthetic Aperture Imaging, Phase Retrieval, And Digital Holography, Dennis Joseph Lee
Open Access Dissertations
Computational imaging has become an important field, as a merger of both algorithms and physical experiments. In the realm of microscopy and optical imaging, an important application is the problem of improving resolution, which is bounded by wavelength and numerical aperture according to the classic diffraction limit. We will investigate the resolution enhancement of phase objects such as transparent biological cells. One key challenge is how to measure phase experimentally. Standard interferometric techniques have the drawback of being sensitive to environmental vibrations and temperature fluctuations, and they use a reference arm which requires more space and cost. Non-holographic methods provide …
A Novel In Vivo Tumor Oxygen Profiling Assay: Combining Functional And Molecular Imaging With Multivariate Mathematical Modeling, Chung-Wein Lee
A Novel In Vivo Tumor Oxygen Profiling Assay: Combining Functional And Molecular Imaging With Multivariate Mathematical Modeling, Chung-Wein Lee
Open Access Dissertations
Purpose: The objective of this study is to develop and test a novel high spatio-temporal in vivo assay to quantify tumor oxygenation and hypoxia. The assay implements a biophysical model of oxygen transport to fuse parameters acquired from in vivo functional and molecular imaging modalities. ^ Introduction: Tumor hypoxia plays an important role in carcinogenesis. It triggers pathological angiogenesis to supply more oxygen to the tumor cells and promotes cancer cell metastasis. Preclinical and clinical evidence show that anti-angiogenic treatment is capable of normalizing the tumor vasculature both structurally and functionally. The resulting normalized vasculature provides a more efficient and …
Control Oriented Concentrating Solar Power (Csp) Plant Model And Its Applications, Qi Luo
Control Oriented Concentrating Solar Power (Csp) Plant Model And Its Applications, Qi Luo
Open Access Dissertations
Solar receivers in concentrating solar thermal power plants (CSP) undergo over 10,000 start-ups and shutdowns, and over 25,000 rapid rate of change in temperature on receivers due to cloud transients resulting in performance degradation and material fatigue in their expected lifetime of over 30 years. The research proposes to develop a three-level controller that uses multi-input-multi-output (MIMO) control technology to minimize the effect of these disturbances, improve plant performance, and extend plant life. The controller can be readily installed on any vendor supplied state-of-the-art control hardware.^ We propose a three-level controller architecture using multi-input-multi-output (MIMO) control for CSP plants that …
Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon
Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon
Open Access Dissertations
Ecosystem services are benefits that people receive from the environment. Despite recent exponential increases in ecosystem service research, the ecosystem service framework has made little impact on policy and land management decisions, especially in the United States. Two of the main limitations for a lack of ecosystem service considerations in both policy and land management decisions are a need for more advanced quantification methods and the lack of engagement of key stakeholders who are responsible for making land management decisions. This research seeks to address these two limitations by testing and improving quantification methods of ecosystem services and by evaluating …
Algorithms For Bundling And Pricing Trucking Services: Deterministic And Stochastic Approaches, Rodrigo Mesa-Arango
Algorithms For Bundling And Pricing Trucking Services: Deterministic And Stochastic Approaches, Rodrigo Mesa-Arango
Open Access Dissertations
Bundling and pricing trucking services is an important strategic decision for carriers. This is helpful when they consider the incorporation of new businesses to their networks, look for economic and optimal operations, and develop revenue management strategies. Reverse combinatorial auctions for trucking services are real-world examples that illustrate the necessity of such strategies. In these auctions, a shipper asks carriers for quotes to serve combinations of lanes and the carriers have to bundle demand and price it properly. This dissertation explores several dimensions of the problem employing state-of-the-art analytical tools. These dimensions include: Truckload (TL) and less-than-truckload (LTL) operations, behavioral …
Loss Of Accuracy Using Smeared Properties In Composite Beam Modeling, Ning Liu
Loss Of Accuracy Using Smeared Properties In Composite Beam Modeling, Ning Liu
Open Access Theses
Advanced composite materials have broad, proven applications in many engineering systems ranging from sports equipment sectors to components on the space shuttle because of their lightweight characteristics and significantly high stiffness. Together with this merit of composite materials is the challenge of improving computational simulation process for composites analysis. Composite structures, particularly composite laminates, usually consist of many layers with different lay-up angles. The anisotropic and heterogeneous features render 3D finite element analysis (FEA) computationally expensive in terms of the computational time and the computing power. ^ At the constituent level, composite materials are heterogeneous. But quite often one homogenizes …
Synthesis And Characterization Of A Lubricin Mimic (Mlub) To Reduce Friction On The Articular Cartilage Surface, Alexandra May Lawrence
Synthesis And Characterization Of A Lubricin Mimic (Mlub) To Reduce Friction On The Articular Cartilage Surface, Alexandra May Lawrence
Open Access Theses
The lubricating proteoglycan, lubricin, facilitates the remarkable low friction and wear properties of articular cartilage in the synovial joints of the body. Lubricin lines the joint surfaces and plays a protective role as a boundary lubricant in sliding contact; down-regulation of lubricin is associated with cartilage degradation and the pathogenesis of osteoarthritis. An unmet need for early osteoarthritis treatment is the development of therapeutic molecules that mimic lubricin function and yet are also resistant to enzymatic degradation common in the damaged joint. Here, we engineered a lubricin mimic (mLub) that resists enzymatic degradation and binds to the articular surface to …
A Nearly Autonomous, Platform-Independent Mobile App For Manure Application Records, Matthew R. Koester
A Nearly Autonomous, Platform-Independent Mobile App For Manure Application Records, Matthew R. Koester
Open Access Theses
A major part of modern manure management is accurate application records; a key to their creation and maintenance is ease. This project involved the integration of existing technologies (smartphones, Bluetooth tags) in mobile web and native Android applications (apps) which enable the autogenic creation and upkeep of manure hauling records. This approach greatly improves the efficiency of the recording process which should help to improve the management of applied nutrients. Features of the app include: computation of a suggested travel speed to ensure target nutrient application (based on desired application rate and spreading width); minimized keystrokes/screen taps to accurately capture …
An Empirical Approach To The Re-Creation Of Vehicle Drive Cycles, Andrew J. Larson
An Empirical Approach To The Re-Creation Of Vehicle Drive Cycles, Andrew J. Larson
Open Access Theses
Vehicles such as buses, delivery trucks, mining equipment, and motorsport vehicles often repeat a highly defined pattern, route, or track during normal use. For these vehicles, standard dynamometer drive cycles are of little use. It was proposed that deriving a vehicle drive cycle from empirical data collected from on-board vehicle sensors would produce more accurate vehicle characteristic predictions for special purpose vehicles. This study answers the question "Is it possible to use recorded vehicle data to replicate a real world driving scenario for the purpose of vehicle diagnostics?" To reduce the complexity of the project, an electric go-kart was used …
Hybrid Power System For Micro Air Vehicles, Bakytgul Khaday
Hybrid Power System For Micro Air Vehicles, Bakytgul Khaday
Open Access Theses
Today Micro Air Vehicles are in need of a good power source that would enable them longer flight time and various functionalities. This work is focused on to this problem. A possible solution that is offered in this study is implementing a hybrid power system consisting of battery and supercapacitor (SCAP). The proposed hybrid power system was tested on an existing MAV platform (Cheerson CX-10). A separate hybrid power printed circuit board (PCB) was designed and manufactured. For experimental and system verification purposes, the PCB was not sized for on-board flight. The hybrid power PCB was connected to MAV through …
Four Runway Configuration Types And Their Relation To Arrival Delays, Rachel Jayne Kennedy
Four Runway Configuration Types And Their Relation To Arrival Delays, Rachel Jayne Kennedy
Open Access Theses
Aside from a safe flight, airline passengers expect to arrive to their destination on time. With an abundance of flights in the United States arriving late each day, it has yet to be determined if the airport's layout plays a role. This research looks at four common runway configuration types at hub and non-hub airports to determine if runway configurations affect arrival delays. A two-way ANOVA is conducted comparing the means of the on-time arrival percentage between airports exhibiting each of the four runway configurations as well as hub and non-hub airport status. The results determine if any or none …
Cerebrovascular Reactivity Alterations Due To Subconcussive Repetitive Head Trauma In Asymptomatic High School Football Players, Chetas Joshi
Open Access Theses
Chronic neurological damage as a result of chronic repetitive head trauma is a major concern for football athletes today. Repetitive concussions have been linked to many neurological disorders. Recently, it has been reported that repetitive subconcussive events can contribute to long-term neurodegeneration. For these reasons, it is important to understand the effect repetitive subconcussive head trauma has on brain health in young athletes. Past research has demonstrated that cerebrovascular reactivity (CVR), an important mediator of cerebrovascular regulation, is impaired following mild traumatic brain injury (mTBI). This impairment increases susceptibility to secondary injury following mTBI. In this study, Breath-Hold (BH) task …
Computational Valve Plate Design, Paul K. Kalbfleisch
Computational Valve Plate Design, Paul K. Kalbfleisch
Open Access Theses
Axial piston machines are widely used in many industries for their designs compactness, flexibility in power transfer, variable flow rate, and high efficiencies as compared to their manufacturing costs. One important component of all axial piston machines that is a very influential on the performance of the unit is the valve plate. The aim of this research is to develop a design methodology that is general enough to design all types of valve plates and the simple enough not to require advanced technical knowledge from the user. A new style of valve plate designs has been developed that comprehensively considers …
Hubcheck: Check The Hub, Derrick S. Kearney
Hubcheck: Check The Hub, Derrick S. Kearney
Open Access Theses
The HUBzero Platform is a framework for building websites, referred to as "hubs," that promote research communities through online simulation, data management, and collaboration. With each software release, the HUBzero Team dedicates weeks of team members' time toward manually testing, fixing, and retesting hub components. The unique mixture of environments that make up a hub makes using existing automated testing solutions hard and shifts the burden of testing to humans, promoting variation, spot checking of fixes, and other shortcuts to avoid the high cost of completely retesting the system. With over twenty hubs being actively managed by the HUBzero Team, …
Using Mixtures Of Fatty Acid Methyl Esters As Phase Change Materials For Concrete, Leah Christine Liston
Using Mixtures Of Fatty Acid Methyl Esters As Phase Change Materials For Concrete, Leah Christine Liston
Open Access Theses
Phase change materials (PCMs) are an effective way of storing/releasing thermal energy via phase transformations. Incorporating PCMs into concrete pavements at airports has been suggested as a means to reduce the accumulation of snow and ice on runways. This thesis reports on the development of two phase change materials composed of binary mixtures of fatty acid methyl esters (FAME) which provide a solid-liquid transition slightly above 0°C with a high enthalpy of fusion. Current findings of this study indicate that these mixtures have the necessary properties to be a high performance PCM with the potential to reduce the levels of …
Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer
Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer
Open Access Theses
The purpose of this research is to investigate the feasibility and advantageous outcomes of modeling a complicated non-linear hybrid dynamical process as an interconnected dynamical system for the purpose of solving a hybrid optimal control problem under the framework of nonlinear model predictive control. This work considers a hybrid model of the startup process of an evaporation system. In this evaporation system a liquid containing mixture of a non-volatile component A and volatile solvents B (water) and C (alcohol) is heated to evaporate the solvents and obtain component A at a higher concentration using a column that is temperature controlled …
Diagnosis Of Systematic Defects Based On Design-For-Manufacturability Guidelines, Dhawal Krishana Gupta
Diagnosis Of Systematic Defects Based On Design-For-Manufacturability Guidelines, Dhawal Krishana Gupta
Open Access Theses
All products in the Very-Large-Scale-Integrated-Circuit (VLSIC) industry go through three major stages of production - Design, Verification and Manufacturing. Unfortunately, neither of these stages are truly perfect, hence we need two more sub-stages of manufacturing, namely Testing and Defect Diagnosis to prevent imperfections in ICs. Testing is used to generate test vectors to validate the functionality of the Device-under-Test (DUT), and Defect Diagnosis is the process of identifying the root-cause of a failing chip, i.e., the location and nature of defect. Systematic defects are unintended structural and material changes at specific locations with a higher probability of failure due to …
Mass Transfer Of Large Molecules Through Collagen And Collagen-Silica Hybrid Membranes, Pedro Jofre Lora
Mass Transfer Of Large Molecules Through Collagen And Collagen-Silica Hybrid Membranes, Pedro Jofre Lora
Open Access Theses
Diabetes is a growing concern in the United States and around the world that must be addressed through new treatment options. Current standard treatment options of diabetes are limiting and have tremendous impacts on patient's lives. Emerging therapies, such as the implantation of encapsulated islets, are promising treatment options, but have not yet materialized due to unsolved problems with material properties. Hybrid silica-collagen membranes address some of these unsolved problems and are a promising material for cell encapsulation. However, the mass transfer properties of large molecules, such as insulin, TNF-α, IL1β, and other important proteins in the etiology of diabetes, …
Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg
Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg
Open Access Theses
Despite the fact that the soil profile is known to impact streamflow, most Curve Number (CN)-based models ignore subsurface processes. This study explores the influence of soil storage on peak flows. Two watersheds in flat, humid west-central Indiana were modeled using both the Natural Resources Conservation Service (NRCS) Curve Number and four versions of the Soil Moisture Accounting (SMA) loss methods in the United States Army Core of Engineers-developed (USACE) Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS). One watershed encompasses the Wabash and Tippecanoe Rivers' confluence; the other contains an ephemeral stream, Plum Creek. The CN-based model was developed using …
Kernel And Bulk Density Changes Due To Moisture Content, Mechanical Damage, And Insect Damage, Danping Guo
Kernel And Bulk Density Changes Due To Moisture Content, Mechanical Damage, And Insect Damage, Danping Guo
Open Access Theses
Corn (Zea Mays), is one of the major grain crops in the world and moisture content, mechanical damage and insect damage are three factors that affect its quality. The primary goal of this thesis was to investigate the effects of moisture content, mechanical damage and insect damage on kernel and bulk density of corn. The study was conducted using two corn hybrids, Pioneer 1352 and Pioneer 1221, that were grown on Purdue Agronomy Farm for Research and Education (ACRE), manually picked and shelled. In Objective 1, the effect of three different moisture conditioning processes (drying from harvest moisture, …
Trajectory Generation For Lane-Change Maneuver Of Autonomous Vehicles, Ashesh Goswami
Trajectory Generation For Lane-Change Maneuver Of Autonomous Vehicles, Ashesh Goswami
Open Access Theses
Lane-change maneuver is one of the most thoroughly investigated automatic driving operations that can be used by an autonomous self-driving vehicle as a primitive for performing more complex operations like merging, entering/exiting highways or overtaking another vehicle. This thesis focuses on two coherent problems that are associated with the trajectory generation for lane-change maneuvers of autonomous vehicles in a highway scenario: (i) an effective velocity estimation of neighboring vehicles under different road scenarios involving linear and curvilinear motion of the vehicles, and (ii) trajectory generation based on the estimated velocities of neighboring vehicles for safe operation of self-driving cars during …
Comprehensively Simulating The Mixed-Mode Progressive Delamination In Composite Laminates, Zhenyuan Gao
Comprehensively Simulating The Mixed-Mode Progressive Delamination In Composite Laminates, Zhenyuan Gao
Open Access Theses
Delamination, or interlaminar debonding, is a commonly observed failure mechanism in composite laminates. It is of great significance to comprehensively simulate the mixed-mode progressive delamination in composite structures because by doing this, people can save a lot of effort in evaluating the safe load which a composite structure can endure.^ The objective of this thesis is to develop a numerical approach to simulating double-cantilever beam (DCB) and mixed-mode bending (MMB) tests and also of specifying/validating various cohesive models. A finite element framework, which consists of properly selecting time integration scheme (explicit dynamic), viscosity, load rate and mass scaling, is developed …
Characterization Of Wake Effects And Loading Status Of Wind Turbine Arrays Under Different Inflow Conditions, Xiangyu Gao
Characterization Of Wake Effects And Loading Status Of Wind Turbine Arrays Under Different Inflow Conditions, Xiangyu Gao
Open Access Theses
The objective of the present work is to improve the accuracy of Actuator Line Modeling (ALM) in predicting the unsteady aerodynamic loadings on turbine blades and turbine wake by assessing different methods used to determine the relative velocity between the rotating blades and wind. ALM is incorporated into a Large Eddy Simulation (LES) solver in OpenFOAM (Open Field Operations and Manipulations). The aerodynamic loadings are validated by experiment results from National Renewable Energy Laboratory (NREL). Turbine wakes are validated by predictions of large eddy simulation using exact 3D blade geometries from a two-blade NREL Phase VI turbine. Three different relative …
Drop Volume Modulation Via Modulated Contact Angle In Inkject Systems, Aaron Fulton
Drop Volume Modulation Via Modulated Contact Angle In Inkject Systems, Aaron Fulton
Open Access Theses
To date, there are limited options in the ability to adjust feature sizes when inkjet printing. The reduction of nozzle size has been the primary method by which smaller features are created. Prior attempts to reduce feature sizes have all come with some restriction or another, as they are only accessible on certain systems, are difficult to manufacture, tune, cause clogging, etc. Few attempts to create droplets of smaller radii than that of the nozzle from which they are produced have been successful. Additionally, many fluids cannot be jetted whatsoever. Existing methods pertain largely to piezoelectric inkjet printing and time …
Bayesian Global Optimization Approach To The Oil Well Placement Problem With Quantified Uncertainties, Zengyi Dou
Bayesian Global Optimization Approach To The Oil Well Placement Problem With Quantified Uncertainties, Zengyi Dou
Open Access Theses
The oil well placement problem is vital part of secondary oil production. Since the calculation of the net present value (NPV) of an investment depends on the solution of expensive partial differential equations that require tremendous computational resources, traditional methods are doomed to fail. The problem becomes exceedingly more difficult when we take into account the uncertainties in the oil price as well as in the ground permeability. In this study, we formulate the oil well placement problem as a global optimization problem that depends on the output of a finite volume solver for the two-phase immiscible flow (water-oil). Then, …
Characterization And Evaluation Of Head Impact Sensors And Varsity Football Helmets, Brian R. Cummiskey
Characterization And Evaluation Of Head Impact Sensors And Varsity Football Helmets, Brian R. Cummiskey
Open Access Theses
An increased understanding of the effects of brain injury in recent years has led to greater attention being given to the topic. A desire to investigate the causal agents of these injuries in athletes has led to the development and use of several devices that track head impacts as well as improving helmet technology to protect players from said impacts. In order to determine which devices are able to best measure head impacts, a Hybrid III headform was used to quantify the accuracy for translational and angular accelerations. Testing was performed by means of administering impacts to a helmet on …