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Full-Text Articles in Engineering

Correction To: Recommendations Of Rilem Tc 260-Rsc For Using Superabsorbent Polymers (Sap) For Improving Freeze–Thaw Resistance Of Cement-Based Materials (Materials And Structures, (2019), 52, 4, (75), 10.1617/S11527-019-1375-4), Viktor Mechtcherine, Christof Schröfl, Michaela Reichardt, Agnieszka J. Klemm, Kamal Khayat Apr 2020

Correction To: Recommendations Of Rilem Tc 260-Rsc For Using Superabsorbent Polymers (Sap) For Improving Freeze–Thaw Resistance Of Cement-Based Materials (Materials And Structures, (2019), 52, 4, (75), 10.1617/S11527-019-1375-4), Viktor Mechtcherine, Christof Schröfl, Michaela Reichardt, Agnieszka J. Klemm, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Agnieszka J. Klemm is affiliated to Glasgow Caledonian University, Glasgow, UK.


Mission Architecture Analysis: Exploring Long-Period Comets From Multiple Staging Orbits, Gabriel Prescinotti Vivan Apr 2020

Mission Architecture Analysis: Exploring Long-Period Comets From Multiple Staging Orbits, Gabriel Prescinotti Vivan

Masters Theses

Objects that have retained pieces of information about the early Solar System are key to our understanding of its formation and evolutionary history. However, the high delta-V required to reach these objects, such as long-period comets or interstellar objects, makes designing an intercept mission at the time of detection impractical. In this thesis, multiple heliocentric staging orbits are explored to serve as departure positions for future missions, prior to objects’ detections. By utilizing more than one staging orbit concurrently, the set of objects that are reachable is expanded, therefore increasing mission feasibility. Delta-V maps are generated and superimposed; two-impulse burn …


Fatigue Damage Characterization By Surface Roughness And Instrumented Micro – Hardness Measurements, Suraj Sanjay Nikam Apr 2020

Fatigue Damage Characterization By Surface Roughness And Instrumented Micro – Hardness Measurements, Suraj Sanjay Nikam

Masters Theses

Fatigue is an essential consideration in the design of high performance, safety-critical structures, and components, as fatigue failure constitutes more than 70% of failures in dynamically loaded components. This research aims to shed light on the effect of surface roughness on the micro-hardness in metals through experimental techniques (Part 1), the correlation between the traditional fatigue testing and instrumented cyclic micro-hardness testing to determine the material properties modeled by Ramberg - Osgood relationship(Part 2), and the effect of the fatigue damage on micro-hardness and surface roughness (Part 3).

For this research, Al 7075 - T651 and Al 6061 - T651 …


Comparison Of Optimal Energy Management Strategies Using Dynamic Programming, Model Predictive Control, And Constant Velocity Prediction, Amol Arvind Patil Apr 2020

Comparison Of Optimal Energy Management Strategies Using Dynamic Programming, Model Predictive Control, And Constant Velocity Prediction, Amol Arvind Patil

Masters Theses

Due to the recent advancements in autonomous vehicle technology, future vehicle velocity predictions are becoming more robust which allows fuel economy (FE) improvements in hybrid electric vehicles through optimal energy management strategies (EMS). A real-world highway drive cycle (DC) and a controls-oriented 2017 Toyota Prius Prime model are used to study potential FE improvements. We proposed three important metrics for comparison: (1) perfect full drive cycle prediction using dynamic programming, (2) 10-second prediction horizon model predictive control (MPC), and (3) 10-second constant velocity prediction. These different velocity predictions are put into an optimal EMS derivation algorithm to derive optimal engine …


Vehicle Performance Analysis Of An Autonomous Electric Shuttle Modified For Wheelchair Accessibility, Johan Fanas Rojas Apr 2020

Vehicle Performance Analysis Of An Autonomous Electric Shuttle Modified For Wheelchair Accessibility, Johan Fanas Rojas

Masters Theses

Autonomous vehicles (AV) have the potential to vastly improve independent, safe, and cost-effective mobility options for individuals with disabilities. However, accessibility considerations are often overlooked in the early stages of design, resulting in AVs that are inaccessible to people with disabilities. The needs of wheeled mobility device users can cause significant vehicle design changes due to requirements for stepless ingress/egress and increased space for onboard circulation and securement. Vehicles serving people with disabilities typically require costly aftermarket modifications for accessibility, which may have unforeseen impacts on vehicle performance and safety, particularly in the case of automated vehicles. In this research, …


An Argument Against Satellite Resiliency: Simplicity In The Face Of Modern Satellite Design, Dax Linville, Robert A. Bettinger Apr 2020

An Argument Against Satellite Resiliency: Simplicity In The Face Of Modern Satellite Design, Dax Linville, Robert A. Bettinger

Faculty Publications

The US Air Force and the wider US government rely heavily on space-based capabilities in various orbital regimes to project national security and sovereignty. However, these capabilities are enabled by the design, launch, and operation of satellites produced with a design methodology that favors large, monolithic, and technologically exquisite space systems. Despite the ability for these satellites to provide enduring and resilient capabilities, they suffer from a woefully long acquisition process that debilitates any prospect of rapid satellite reconstitution in the event of a space war.


Using Scrap Tires As An Aggregate In Chip Seal - Phase Ii, Alireza Pourhassan, Ahmed Gheni, Mohamed Elgawady Apr 2020

Using Scrap Tires As An Aggregate In Chip Seal - Phase Ii, Alireza Pourhassan, Ahmed Gheni, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Technical Reports

Chip seals are one of the most cost and performance effective pavement preservation treatments commonly used in the United States. An eco-friendly chip seal pavement, in which the natural aggregate was replaced by crumb rubber obtained from scrap tires, was recently developed by the research team at Missouri S&T, creating rubberized chip seal. This project investigated and optimized the performance of rubberized chip seal under different scenarios. During this project, laboratory chip seal specimens with different sizes were prepared and tested under simulated traffic loads with different loading parameters and environmental conditions. Also, the feasibility of the implementation and performance …


Low Leakage Gan Hemts With Sub-100 Nm T-Shape Gates Fabricated By A Low-Damage Etching Process, Siqi Lei, Wei Chih Cheng, Jingyi Wu, Liang Wang, Qing Wang, Guangrui Xia, Feng Zhao, Hongyu Yu Apr 2020

Low Leakage Gan Hemts With Sub-100 Nm T-Shape Gates Fabricated By A Low-Damage Etching Process, Siqi Lei, Wei Chih Cheng, Jingyi Wu, Liang Wang, Qing Wang, Guangrui Xia, Feng Zhao, Hongyu Yu

Electrical and Computer Engineering Faculty Research & Creative Works

This paper demonstrates a new fabrication process for gallium nitride high-electron mobility transistors (HEMTs) free of plasma damages in the sub-100 nm T-shape gate area. The common peeling-off problems of electron beam resists during gate metal deposition process were solved by introducing a fluorine plasma treatment process before gate metal deposition. By combining dry and wet etching processes appropriately, an on/off ratio of 107 at a drain-to-source voltage of 1 V was achieved. This work also investigated the short channel effect in devices with gate lengths from 70 to 440 nm. Reducing gate length results in decrease of threshold …


Development Of A Finite Element Model Of The Stamping Process To Predict The Natural Frequencies Of Dimpled Beams, Varad Vasudeo Pendse Apr 2020

Development Of A Finite Element Model Of The Stamping Process To Predict The Natural Frequencies Of Dimpled Beams, Varad Vasudeo Pendse

Masters Theses

Creating dimples on beams has been proven to be an effective way of altering their vibrational behavior. The objective of this research is to simulate the process of stamping using the finite element (FE) method to create a model of a dimpled beam. This dimple has non-uniform thickness, so it shows close agreement with its real-life counterpart.

ANSYS® Parametric Design Language (APDL) is used to build a three-dimensional (3-D) finite element model and simulate the process of stamping used to create the dimple. The structural simulation is validated by calculating the thickness and width of the deformed geometry of the …


Vehicle Velocity Prediction Using Artificial Neural Networks And Effect Of Real-World Signals On Prediction Window, Tushar Dnyaneshwar Gaikwad Apr 2020

Vehicle Velocity Prediction Using Artificial Neural Networks And Effect Of Real-World Signals On Prediction Window, Tushar Dnyaneshwar Gaikwad

Masters Theses

Prediction of vehicle velocity is essential since it can realize improvements in the fuel economy/energy efficiency, drivability, and safety. Many publications address velocity prediction problems, yet there is a need for the understanding effect of different signals for the prediction. There are numerous new sensor and signal technologies like vehicle-to-vehicle and vehicle-to-infrastructure communication that can be used to obtain comprehensive datasets. Several references considered deterministic and stochastic approaches that use the datasets as input to determine future operation predictions. These approaches include different traffic models and artificial neural networks such as Markov chain, nonlinear autoregressive model, Gaussian function, and recurrent …


The Effect Of Including Pressure Within Cracks On Failure Times Of Cylinders Subjected To Internal Air Blast Loading, Molly M. Bailey Apr 2020

The Effect Of Including Pressure Within Cracks On Failure Times Of Cylinders Subjected To Internal Air Blast Loading, Molly M. Bailey

Mechanical Engineering ETDs

The importance of internal crack pressure on the extent of crack propagation is studied using both numerical and experimental results. Experimental data were obtained from shock tube testing of internally pressurized quasi-brittle hollow cylinders loaded to failure. Half of the samples were tested with an inserted membrane that transferred the shocked fluid load but prevented the fluid from entering the developing cracks. In the other cases, the membrane was removed allowing the fluid to enter the crack and assist development of fracture. A novel approach to modeling this complex structural response involving dynamic failure and fluid structure interaction is presented, …


Virtual Satcom, Long Range Broadband Digital Communications, Dennis George Watson Apr 2020

Virtual Satcom, Long Range Broadband Digital Communications, Dennis George Watson

Electrical & Computer Engineering Theses & Dissertations

The current naval strategy is based on a distributed force, networked together with high-speed communications that enable operations as an intelligent, fast maneuvering force. Satellites, the existing network connector, are weak and vulnerable to attack. HF is an alternative, but it does not have the information throughput to meet the distributed warfighting need. The US Navy does not have a solution to reduce dependency on space-based communication systems while providing the warfighter with the required information speed.

Virtual SATCOM is a solution that can match satellite communications (SATCOM) data speed without the vulnerable satellite. It is wireless communication on a …


Highly Transmissive Scalable Colored Coatings For Architectural Photovoltaic Panels, Akbar Ali Syed Apr 2020

Highly Transmissive Scalable Colored Coatings For Architectural Photovoltaic Panels, Akbar Ali Syed

Electrical & Computer Engineering Theses & Dissertations

Highly transmissive coatings were developed by fabricating thin films using SiO2 and SiO2/TiO2 core/shell nanoparticles on glass substrates and on the photovoltaic cell glass covers. This coating is to maintain an attractive color appearance of the exterior surface for architecturally integrated photovoltaics and can be coated on fabricated photovoltaic panels. The color and optical properties of the nanoparticle coating was investigated for different nanoparticle diameters of 200-400 nm for SiO2 nanoparticles and core/shell nanoparticles having SiO2/TiO2 structure with 300 ± 11 nm diameter, and SiO2/TiO2/SiO2 structure with …


Flexible Electrochemical Lactate Sensor, Peyton Miesse Apr 2020

Flexible Electrochemical Lactate Sensor, Peyton Miesse

Biomedical Engineering Theses & Dissertations

Lactic acid is a vital indicator for shock, trauma, stress, and exercise intolerance. It is a key biomarker for increases in stress levels and is the primary metabolically produced acid responsible for tissue acidosis that can lead to muscle fatigue and weakness. During intensive exercise, the muscles go through anerobic metabolism to produce energy. This leads to decreases in the blood flow of nutrients and oxygen to the muscles and increases in lactate production, which in turn cause lactic acidosis. Currently, changes in blood lactate concentrations are monitored by sensors that can be invasive via blood or wearable based sensors …


Impedance Analysis Of Tissues In Nspef Treatment For Cancer Therapy, Edwin Ayobami Oshin Apr 2020

Impedance Analysis Of Tissues In Nspef Treatment For Cancer Therapy, Edwin Ayobami Oshin

Biomedical Engineering Theses & Dissertations

Nanosecond pulsed electric field (nsPEF) for cancer therapy is characterized by applications of high voltage pulses with low pulsed energy to induce non-thermal effects on tissues such as tumor ablation. It nonthermally treats tissues via electroporation. Electroporation is the increase in permeabilization of a cell membrane due to the application of high pulsed electric field. The objective of this study was to investigate the effect of nsPEF on tissue by monitoring the tissue’s impedance in real-time. Potato slices (both untreated and electroporated), and tumors extracted from female BALBc mice were studied. 100ns, 1-10kV pulses were applied to the tissues using …


Compaction And Residual Stress Modeling In Composite Manufactured With Automated Fiber Placement, Von Clyde Jamora Apr 2020

Compaction And Residual Stress Modeling In Composite Manufactured With Automated Fiber Placement, Von Clyde Jamora

Mechanical & Aerospace Engineering Theses & Dissertations

Automated fiber placement is a state-of-the-art manufacturing process that allows for complex layup patterns and can quickly place, cut, and restart composite tows. However, with this type of manufacturing process layup defects are inevitable, and manufacturing defects propagate after curing. Process modeling is the considered approach for exploring the defect prediction. Two different but related works were conducted, which are the thermochemical and hyperelastic model and the residual deformation model. For the model before cooling, a hyperelastic model and a thermo-chemical were made to simulate the compaction and heat transfer. Temperature dependent properties that are a function of degree of …


Application Of Theory Of Constraints (Toc) In Managing Project Information Constraints, Ferdinand Z. Prantl Apr 2020

Application Of Theory Of Constraints (Toc) In Managing Project Information Constraints, Ferdinand Z. Prantl

EMSE Doctoral Projects

The scope of this doctoral project is the non-traditional application of Drum-Buffer-Rope (DBR) from the area of Theory of Constraints (ToC) in mitigating disruption in distribution facilities during phased upgrades caused by information constraint. The relevance of this project is that industrial equipment upgrades pose a significant risk of disrupting the operation of automated distribution facilities. It is partly due to a very high expected availability rate, as well as tight coupling with other upstream and downstream elements of the larger supply chain network. As a consequence of disruption in this scenario, losses incurred not only within the facility being …


Investigation Of Manual Material Handling On Musculoskeletal Disorder At Computer Numerical Control Workstation, Abdullah Nor Suliani Apr 2020

Investigation Of Manual Material Handling On Musculoskeletal Disorder At Computer Numerical Control Workstation, Abdullah Nor Suliani

Student Works (2020-2029)

Manual Material Handling (MMH) tasks have been recognized among the major source of work-related musculoskeletal disorder (WMSD) in automotive industry and they are commonly practiced at Computer Numerical Control (CNC) workstation. At this workstation, workers act as a material transfer device in the process of loading and unloading products from pallets to machines. The physical interaction of workers to machine is not self-chosen and workers are forced to follow the pace of running CNC machine. The worst situation happens when workers are required to operate more than one machine concurrently. The mismatch interaction between workers and machine exposes workers to …


Production Of Renewable Hydrocarbon Fuel Via Titanium Oxide-Alumina (Tio2-Al2o3) Catalytic Deoxygenation Reaction, Xian Yih Ooi Apr 2020

Production Of Renewable Hydrocarbon Fuel Via Titanium Oxide-Alumina (Tio2-Al2o3) Catalytic Deoxygenation Reaction, Xian Yih Ooi

Student Works (2020-2029)

The renewable hydrocarbon-like biofuel from biomass is crucial to substitute fossil fuel. Catalytic deoxygenation is a biofuel upgrading process to eliminate the high oxygen content in biofuel which will lead to corrosion, instability and lower heating value problems. The choice of support is significant to provide the maximum acid strength for the hydrogenolysis of C-O bonds. Al2O3 supported catalyst has drawn attention due to the high acidity. However, the high acidity leads to coke deposition, unstable and deactivation of the catalyst. Thus, it is important to develop methods to improve catalyst performance, reduce catalyst coking and enhance catalyst lifetime. Recently, …


Poly(Vinyl Alcohol)/Α-Chitin/Nanocellulose Composites Developed From Oil Palm Empty Fruit Bunch (Opefb) For Removal Of Cationic Dyes, Chun Fah Mok Apr 2020

Poly(Vinyl Alcohol)/Α-Chitin/Nanocellulose Composites Developed From Oil Palm Empty Fruit Bunch (Opefb) For Removal Of Cationic Dyes, Chun Fah Mok

Student Works (2020-2029)

In search of an eco-friendly polymeric adsorbent for dye effluent treatment application, poly(vinyl alcohol) (PVA)/chitin/nanocellulose composites were synthesized. The composites were reinforced by oil palm empty fruit bunch fibers (OPEFB)-derived nanocrystalline cellulose (NCC). With addition of 1 wt.% NCC, a maximum improvement of 57.64% and 50.66% in tensile strength and Young’s Modulus were achieved, respectively. However, the PVA-based composites exhibited low resistance in aqueous medium. Hence, maleic acid (MA) was incorporated, in view of modifying PVA-based composites through cross-linking reactions. The effect of varying chitin content (10 wt.%-30 wt.%) and MA content (10%-50% based on total solid content of composite) …


Fatigue Damage Assessment Of Reinforced Concrete Slabs Using Integrated Dynamic Testing And Simulation, Jamadin Adiza Apr 2020

Fatigue Damage Assessment Of Reinforced Concrete Slabs Using Integrated Dynamic Testing And Simulation, Jamadin Adiza

Student Works (2020-2029)

Assessment of existing fatigued structures is an important aspect of civil engineering infrastructure. This is critical in most loaded civil engineering structures such as bridges that are constantly subjected to dynamic loading, causing fatigue in the materials over time. Bridge deck slabs are one of the most structural elements susceptible to different cyclic loads, requiring regular checks for damage to fatigue. In order to understand the deterioration, fatigue carrying capacity and residual strength, the serviceability of the slab under the fatigue loads was not fully explored. Therefore, this research is designed to use vibration-based techniques to investigate the integrity of …


Development Of B-Type And Multi-Ion Doped Carbonated Hydroxyapatite Bioceramics, Safarzadeh Marjan Apr 2020

Development Of B-Type And Multi-Ion Doped Carbonated Hydroxyapatite Bioceramics, Safarzadeh Marjan

Student Works (2020-2029)

The present research is aimed to investigate the effect of varying the carbonate to phosphate (CO32−/ PO43‒) molar ratios from 0.5 to 5 on the physical and mechanical properties of carbonated hydroxyapatite (CHA) synthesized by a wet chemical method. The sintering was performed under dry carbon dioxide atmosphere at 900 °C to maintain the B-type CHA structure. It was found that increases in CO32−/ PO43‒ ratio was accompanied by an increase in the c/a lattice ratio. The diffraction peaks of the synthesized 0.5-5 CHA powders exhibited a single phase material except for 5CHA which revealed the some minor calcite or …


Hybrid Non-Destructive Assessment For Flow Induced Vibration Piping Systems Using Coupled Fluid-Structure Interaction, Keen Kuan Kong Apr 2020

Hybrid Non-Destructive Assessment For Flow Induced Vibration Piping Systems Using Coupled Fluid-Structure Interaction, Keen Kuan Kong

Student Works (2020-2029)

Pipelines and piping systems are of great importance in many industries such as water supply, petroleum and petrochemicals and nuclear power generation. They provide transport for high-velocity pressurized fluids operating under time-varying conditions. They are required to operate non-stop for a schedule of 24 hours a day, 7 days a week. Piping vibration failures have been one of the major causes of downtime, fires and explosions in industrial plant over the past 30 years. Failure of piping systems can have disastrous effects, leading to injuries and fatalities as well as to substantial cost to industry and the environment. Flow-induced vibration …


Influence Of Cr Content On The Microstructure And Mechanical Properties Of Crxfenicu High Entropy Alloys, Hao Wu, Sirui Huang, Chengyan Zhu, Heguo Zhu, Zonghan Xie Apr 2020

Influence Of Cr Content On The Microstructure And Mechanical Properties Of Crxfenicu High Entropy Alloys, Hao Wu, Sirui Huang, Chengyan Zhu, Heguo Zhu, Zonghan Xie

Research outputs 2014 to 2021

© 2020 Chinese Materials Research Society The effect of Cr content on the microstructure and mechanical properties of CrxFeNiCu high entropy alloys (HEAs) was firstly studied by first-principles calculations. The calculated results show that the hardness of the alloys increased with the expense of its plasticity decrease, if the content of Cr in the alloy increased. In order to verify the calculated results, CrxFeNiCu (x = 0.8, 1, 1.5 and 2) high entropy alloys were synthesized by vacuum induction melting in the present study. The results show that as the value of x increased from 0.8 to 2, the crystal …


Optimal Sizing Design And Operation Of Electrical And Thermal Energy Storage Systems In Smart Buildings, Ali Baniasadi, Daryoush Habibi, Waleed Al-Saedi, Mohammad A. S. Masoum, Choton K. Das, Navid Mousavi Apr 2020

Optimal Sizing Design And Operation Of Electrical And Thermal Energy Storage Systems In Smart Buildings, Ali Baniasadi, Daryoush Habibi, Waleed Al-Saedi, Mohammad A. S. Masoum, Choton K. Das, Navid Mousavi

Research outputs 2014 to 2021

Photovoltaic (PV) systems in residential buildings require energy storage to enhance their productivity; however, in present technology, battery storage systems (BSSs) are not the most cost-effective solutions. Comparatively, thermal storage systems (TSSs) can provide opportunities to enhance PV self-consumption while reducing life cycle costs. This paper proposes a new framework for optimal sizing design and real-time operation of energy storage systems in a residential building equipped with a PV system, heat pump (HP), thermal and electrical energy storage systems. For simultaneous optimal sizing of BSS and TSS, a particle swarm optimization (PSO) algorithm is applied to minimize daily electricity and …


Analysis Of Military Construction Cost Growth In Usaf Major Defense Acquisition Programs, Emily E. Angell, Edward D. White, Jonathan D. Ritschel, Alfred E. Thal Jr. Apr 2020

Analysis Of Military Construction Cost Growth In Usaf Major Defense Acquisition Programs, Emily E. Angell, Edward D. White, Jonathan D. Ritschel, Alfred E. Thal Jr.

Faculty Publications

This study uses descriptive and inferential statistics to identify cost growth Analysis of Military Construction of military construction (MILCON) at the programmatic level, while bridging the gap between Selected Acquisition Report (SAR) estimates and actual project costs. Findings of this study aid the cost community with appropriate allocation of resources in developing these estimates. Overall, Major Defense Acquisition Programs (MDAP) appear to experience more negative growth (cost savings) in MILCON estimates on reviewed SARs— typically less than 0.2% of the total program cost. SAR estimates became more accurate from the first to last SAR in comparison to the total MILCON …


Supporting Self-Regulation Of Children With Adhd Using Wearables: Tensions And Design Challenges, Franceli L. Cibrian, Kimberley D. Lakes, Arya Tavakoulnia, Kayla Guzman, Sabrina Schuck, Gillian R. Hayes Apr 2020

Supporting Self-Regulation Of Children With Adhd Using Wearables: Tensions And Design Challenges, Franceli L. Cibrian, Kimberley D. Lakes, Arya Tavakoulnia, Kayla Guzman, Sabrina Schuck, Gillian R. Hayes

Engineering Faculty Articles and Research

The design of wearable applications supporting children with Attention Deficit Hyperactivity Disorders (ADHD) requires a deep understanding not only of what is possible from a clinical standpoint but also how the children might understand and orient towards wearable technologies, such as a smartwatch. Through a series of participatory design workshops with children with ADHD and their caregivers, we identified tensions and challenges in designing wearable applications supporting the self-regulation of children with ADHD. In this paper, we describe the specific challenges of smartwatches for this population, the balance between self-regulation and co-regulation, and tensions when receiving notifications on a smartwatch …


Experimental Determination Of The (0/−) Level For Mg Acceptors In Β-Ga2O3 Crystals, Christopher A. Lenyk, Timothy D. Gustafson, Sergey A. Basun, Larry E. Halliburton, Nancy C. Giles Apr 2020

Experimental Determination Of The (0/−) Level For Mg Acceptors In Β-Ga2O3 Crystals, Christopher A. Lenyk, Timothy D. Gustafson, Sergey A. Basun, Larry E. Halliburton, Nancy C. Giles

Faculty Publications

Electron paramagnetic resonance (EPR) is used to experimentally determine the (0/−) level of the Mg acceptor in an Mg-doped β-Ga2O3 crystal. Our results place this level 0.65 eV (±0.05 eV) above the valence band, a position closer to the valence band than the predictions of several recent computational studies. The crystal used in this investigation was grown by the Czochralski method and contains large concentrations of Mg acceptors and Ir donors, as well as a small concentration of Fe ions and an even smaller concentration of Cr ions. Below room temperature, illumination with 325 nm laser light …


Applying Control Abstraction To The Design Of Human–Agent Teams, Clifford D. Johnson, Michael E. Miller, Christina F. Rusnock, David R. Jacques Apr 2020

Applying Control Abstraction To The Design Of Human–Agent Teams, Clifford D. Johnson, Michael E. Miller, Christina F. Rusnock, David R. Jacques

Faculty Publications

Levels of Automation (LOA) provide a method for describing authority granted to automated system elements to make individual decisions. However, these levels are technology-centric and provide little insight into overall system operation. The current research discusses an alternate classification scheme, referred to as the Level of Human Control Abstraction (LHCA). LHCA is an operator-centric framework that classifies a system’s state based on the required operator inputs. The framework consists of five levels, each requiring less granularity of human control: Direct, Augmented, Parametric, Goal-Oriented, and Mission-Capable. An analysis was conducted of several existing systems. This analysis illustrates the presence of each …


Single-Pulse, Kerr-Effect Mueller Matrix Lidar Polarimeter, Keyser, Christian K., Richard K. Martin, Helena Lopez-Aviles, Khanh Nguyen, Arielle M. Adams, Demetrios Christodoulides Apr 2020

Single-Pulse, Kerr-Effect Mueller Matrix Lidar Polarimeter, Keyser, Christian K., Richard K. Martin, Helena Lopez-Aviles, Khanh Nguyen, Arielle M. Adams, Demetrios Christodoulides

Faculty Publications

We present a novel light detection and ranging (LiDAR) polarimeter that enables measurement of 12 of 16 sample Mueller matrix elements in a single, 10 ns pulse. The new polarization state generator (PSG) leverages Kerr phase modulation in a birefringent optical fiber, creating a probe pulse characterized by temporally varying polarization. Theoretical expressions for the Polarization State Generator (PSG) Stokes vector are derived for birefringent walk-off and no walk-off and incorporated into a time-dependent polarimeter signal model employing multiple polarization state analyzers (PSA). Polarimeter modeling compares the Kerr effect and electro-optic phase modulator–based PSG using a single Polarization State Analyzer …