Characterization Analysis And Design Of Mid-Wave Infrared Iii- V-Based Type-Ii Superlattice Nbn Photodetectors For Space Applications, Alexander Timothy Newell

Electrical and Computer Engineering ETDs

The performance of the mid-wave infrared InGaAs/InAsSb nBn photodetector is investigated and its viability for space applications is assessed. Three structures are grown with unique absorber layer doping profiles via molecular beam epitaxy. Material and device characterizations are performed and analyzed to determine the effects of doping on fundamental material parameters and detector performance. Noise-equivalent irradiance is calculated to be a factor of 4x that of an ideal detector exhibiting Rule 07 dark current and 100% quantum efficiency, demonstrating high sensitivity. The structures are then irradiated with 63 MeV protons to evaluate the extent of performance degradation over the course …

Analog Artificial Neurons And Digital Amplifiers: Challenging The Roles Of Analog And Digital Circuit Architectures In Modern Cmos Processes, Taylor S. Barton

Theses and Dissertations

As complimentary metal-oxide semiconductor (CMOS) technologies scale and field-effect transistor (FET) architectures change, the factors in deciding to utilize analog or digital transistor behaviors evolve. This thesis examines three case studies where traditionally analog or digital circuitry has dominated published works but I show that the opposite regime has significant benefits in scaled CMOS technologies. I present a highly digital operational amplifier (traditionally analog) and two artificial neurons (traditionally digital). In Chapters 2 and 3 I present a highly-digital five-stage zero-crossing-based amplifier which breaks the trade-off between slew rate and settling accuracy. I investigate the optimal charge pump design by …

Machine Learning For Electronic Design Automation: Specification Mining And High-Level Synthesis, Md Rubel Ahmed

USF Tampa Graduate Theses and Dissertations

The rapid growth of complex system-on-chip (SoC) designs has presented unprecedented opportunities and challenges in electronic design automation (EDA). This dissertation explores two facets of electronic design automation: message flow specification mining using data mining and natural language processing (NLP) and high-level synthesis (HLS) acceleration using different machine learning (ML) methods. It also discusses an ML model co-optimization method for energy-efficient hardware implementation.

Effective SoC design validation relies heavily on message flow specifications. This dissertation presents an efficient technique for synthesizing finite state automaton (FSA) models from SoC execution traces. The synthesized models can provide valuable insights into the on-chip …

Environmental Sustainability Of Small Wastewater Treatment Systems And Pathways For Improvement, Matthew James Thompson

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Wastewater treatment protects society and the environment by reducing pollutants generated from communities prior to discharge into local water bodies. Small water resource recovery facilities (WRRFs) represent the majority of centralized wastewater treatment systems, are resource intensive, and often lack resources needed to evaluate sustainability improvements. The goal of this dissertation was to identify primary sources and drivers of environmental impacts in small WRRFs and exploration of pathways to improve their environmental sustainability.

Case study data collected from small WRRFs in Nebraska was analyzed using environmental life cycle assessment (LCA) to quantify the environmental impact of facilities and existing opportunities. …

Room Temperature Two-Dimensional Electron Gas Scattering Time, Effective Mass, And Mobility Parameters In AlXGa1−XN/Gan Heterostructures (0.07 ≤ X ≤ 0.42), Sean Knight, Steffen Richter, Alexis Papamichail, Philipp Kühne, Nerijus Armakavicius, Shiqi Guo, Axel R. Persson, Vallery Stanishev, Viktor Rindert, Per O. Å. Persson, Plamen P. Paskov, Mathias Schubert, Vanya Darakchieva

Department of Electrical and Computer Engineering: Faculty Publications

Al_xGa_1-xN/GaN high-electron-mobility transistor (HEMT) structures are key components in electronic devices operating at gigahertz or higher frequencies. In order to optimize such HEMT structures, understanding their electronic response at high frequencies and room temperature is required. Here, we present a study of the room temperature free charge carrier properties of the two-dimensional electron gas (2DEG) in HEMT structures with varying Al content in the Al_xGa_1-xN barrier layers between x = 0:07 and x = 0:42. We discuss and compare 2DEG sheet density, mobility, effective mass, sheet resistance, and scattering times, …

Durability Of Cfrp/Steel Bond In Natural Weather, Mastour Alsulami

USF Tampa Graduate Theses and Dissertations

Fiber reinforced polymers (FRP) are increasingly being used for infrastructurestrengthening and repair of steel structures. Though there have been several durability studies, exposures used are not representative of outdoor service conditions. Fewer studies have explored the effect of changing outdoor conditions typical in infrastructure use. The goal of the research is addressing this gap by evaluating the performance of commercially available CFRP systems under natural weather characteristic of hot, humid tropical conditions mainly and cold weather secondary in three different locations.

Thirty CFRP/steel joint specimens were prepared in laboratory conditions and exposed to ambient temperature on the Engineering building roofs …

Reynolds-Averaged Navier-Stokes Simulations Of Nearshore Langmuir Circulation And The Formation Of Oil-Particle Aggregates, Juan J. Penaloza Gutierrez

USF Tampa Graduate Theses and Dissertations

Langmuir turbulence in the inner shelf coastal ocean is characterized by Langmuir circulation (LC) or cells that can span the full depth of unstratified water columns. A Reynolds-averaged Navier-Stokes (RANS) simulation strategy resolving full-depth LC coupled with an oil-particle aggregate (OPA) formation model is introduced. The RANS methodology is employed in two different cases. The first case corresponds to a shallow shelf zone of uniform depth, focusing on vertical mixing and transport of OPAs. The second case pertains to a surf-shelf transition zone with variable depth, comprising vertical and horizontal mixing of OPAs. In the latter case, a wave model …

Mechanisms Contributing To Hydrogen-Influenced Early Failure Of Bridge Tendons, David Dukeman

USF Tampa Graduate Theses and Dissertations

Failures in post-tensioned tendons have occurred without warning due to fractures in the high-strength steel strands. These strands are cold-drawn to increase their strength while still retaining the preferential ductile mode of fracture. Recently, a tendon failure that occurred in an upper deviation block of the I-526 James B. Edwards bridge crossing the Wando river showed signs of corrosion and potentially another method of failure, hydrogen embrittlement. One proposed source of hydrogen is through galvanic coupling that may exist between the galvanized steel duct and the steel strands. This coupling, if substantial, can promote hydrogen evolution at the steel strand's …

Comparative Evaluation Of Investigation Methods For Estimating The Load-Dependent State Of Charge And End Of Discharge Of A Multirotor Uav Battery, Hanna Dibbern, Morten Roßberg, Claudia Werner

Journal of Aviation Technology and Engineering

As the scope of multirotor unmanned aerial vehicle (UAV) applications increases, more attention is being paid to UAV energy requirements, which vary depending on the mission profile. To obtain accurate information about the UAV battery during flight, the idea of a digital twin including a battery state estimation model is promising. For battery state estimation, a Kalman filter combination is the preferred approach in the literature. Comparing different Kalman filters, the unscented Kalman filter has a more accurate estimation for nonlinear systems compared to the extended Kalman filter. In the application of UAV flight with load-dependent flight missions, the comparison …

The Impact Of Smart Architecture Technologies On The Architectural Education System In Facing Crises, Marwa Ahmed Kamer Eldawla, Azza Sobhi Elsakka

Mansoura Engineering Journal

Countries have been exposed to many crises during the last five years, starting with the spread of the Corona epidemic and the subsequent epidemics in the world, and the recurrence of economic crises and others, which affected the architectural education system and with technological progress in all fields, especially in the field of architecture, it has appeared Smart architecture applications in its various aspects (the environmental aspect - the technical aspect - the economic aspect - the social aspect - the formative aspect), which can be used in the development of the architectural education system (physical equipment - human elements …

Using Severity Weighted Risk Scores To Prioritize Safety Funding In Utah, Tomas Barriga Aristizabal

Theses and Dissertations

Budgets for transportation improvements are limited so it is important for governments to focus on improving locations most in need of safety funding. The objective of the Two-Output Model for Safety (TOMS) is to provide the Utah Department of Transportation (UDOT) a reliable method to prioritize safety improvements on state-owned roadways among the different regions. This research will improve the existing Crash Analysis Methodology for Segments (CAMS) and Intersection Safety Analysis Methodology (ISAM) being used to analyze crashes on Utah roadways. The scope of this project is improving on the existing CAMS and ISAM to work together within R, to …

A Bridge Information Modeling (Brim) Framework For Inspection And Maintenance Intervention In Reinforced Concrete Bridges, Ahmed Gouda Mohamed

Civil Engineering

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A Bridge Information Modeling (BrIM) Framework for Inspection and Maintenance Intervention in Reinforced Concrete Bridges

Integrative Transcriptomics And Proteomics Profiling Of Arabidopsis Thaliana Elucidates Novel Mechanisms Underlying Spaceflight Adaptation, Gbolaga O. Olanrewaju, Natasha J. Haveman, Michael J. Naldrett, Anna-Lisa Paul, Robert J. Ferl, Sarah E. Wyatt

Nebraska Center for Biotechnology: Faculty and Staff Publications

Spaceflight presents a unique environment with complex stressors, including microgravity and radiation, that can influence plant physiology at molecular levels. Combining transcriptomics and proteomics approaches, this research gives insights into the coordination of transcriptome and proteome in Arabidopsis’ molecular and physiological responses to Spaceflight environmental stress. Arabidopsis seedlings were germinated and grown in microgravity (μg) aboard the International Space Station (ISS) in NASA Biological Research in Canisters – Light Emitting Diode (BRIC LED) hardware, with the ground control established on Earth. At 10 days old, seedlings were frozen in RNA-later and returned to Earth. RNA-seq transcriptomics and TMTlabeled LC-MS/MS proteomic …

Assessment Of The Feasibility Of Permeable Pavement For Sustainable Stormwater Management Using Swmm, Al Patrick C. Castro, Ma. Aleissa Janelle M. Castillo, Carmela Rose V. Timario, David Timothy F. Go, Marla C. Maniquiz-Redillas

Sinaya: A Philippine Journal for Senior High School Teachers and Students

The advancement of urbanization in the Philippines changed natural lands into impervious surfaces and aided the contamination of surface runoff and nearby water bodies. Low Impact Development (LID) technologies were introduced as an alternative to conventional drainage systems, specifically permeable pavements. Such technology is beneficial for stormwater runoff reduction, ground infiltration enablement, and stormwater treatment. This research was conducted to investigate the feasibility of permeable pavement for sustainable stormwater management in a university setting, particularly in De La Salle University – Laguna Campus. The Storm Water Management Model (SWMM) was utilized to simulate different rainfall scenarios on selected little to …

Optimizing The Dynamic Replacement Of Soft Soils With Sand Using A Fem Tools, Walid Salem A Elsiwi

USF Tampa Graduate Theses and Dissertations

First a dynamic finite element methodology (FEM) was developed to simulate an entire dynamic replacement (DR) program of clay with sand involving multiple poundings. The main objective of this research was to employ FEM and geotechnical test data such as cone penetration test (CPT) data at the site to predict the maximum achievable sand column (SC) depth and the corresponding optimum levels of attributing parameters such as number and height of pounder drops. Another goal was to predict the pore pressure generated in clay due to pounding. A full-scale ground improvement project was used to guide the analytical process. Comparison …

Predictive Modelling Of Road Deterioration Using An Artificially Intelligent Bayesian Belief Networks Approach, Babitha Elizabeth Philip

Thesis/ Dissertation Defenses

The ability to predict road deterioration is the cornerstone for developing a reliable Pavement Management System (PMS) that optimizes pavement maintenance programs. Such prediction capacity becomes increasingly important, especially when highway agency funds are confined. This research focuses on the development of prediction models based on an artificial intelligence technique, Bayesian Belief Networks (BBN), that aid decision-makers in forecasting expected road distress curves on the lights of various (e.g., environmental, traffic, and road-specific) factors and maintenance decisions. The novelty of this research revolves around deploying BBNs which allow analysts to yield Markovian predictions of annual road deterioration based on incomplete …

Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq

Thesis/ Dissertation Defenses

Recycling construction waste material offers a sustainable solution to the problem of disposing of concrete construction and demolition waste. The use of basalt fibers (BF) and basalt fiber-reinforced polymer (BFRP) reinforcing bars in concrete structures made of recycled concrete aggregate (RCA) would prolong their service life and reduce the maintenance cost. This research aims to investigate the potential use of BF, RCA, and BFRP reinforcing bars to produce sustainable and steel-free structural concrete. The study consisted of material characterization testing, numerical simulation, and large-scale beam testing.
Material characterization tests were performed on normal-strength concrete (NSC) and high-strength concrete (HSC). The …

Six-Degree-Of-Freedom Optimal Feedback Control Of Pinpoint Landing Using Deep Neural Networks, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua

Student Works

Machine learning regression techniques have shown success at feedback control to perform near-optimal pinpoint landings for low fidelity formulations (e.g. 3 degree-of-freedom). Trajectories from these low-fidelity landing formulations have been used in imitation learning techniques to train deep neural network policies to replicate these optimal landings in closed loop. This study details the development of a near-optimal, neural network feedback controller for a 6 degree-of-freedom pinpoint landing system. To model disturbances, the problem is cast as either a multi-phase optimal control problem or a triple single-phase optimal control problem to generate examples of optimal control through the presence of disturbances. …

Notes For Contributors, Space And Defense

Space and Defense

No abstract provided.

Publisher’S Corner Space Policy’S Salt Moment, Roger G. Harrison

Space and Defense

The market for a leap forward in space arms control is open. Now, who’s buying? The United States is facing a fundamental decision about space policy which arises from a question: does our national interest in an ordered space environment trump our absolute insistence on a policy of freedom of action? Or is the looming threat of over-crowded orbits, frequency interference and debris – of contested, congested and competitive space – so pressing that we must accept some greater transparency for our national security space operations, even greater information sharing with China, Russia, and commercial space operators, and perhaps some …

Book Review Crowded Orbits: Conflict And Cooperation In Space By James Clay Moltz (Columbia University Press, 2014), Deron Jackson

Space and Defense

A popular space primer serves both the policy and academic communities. Human beings have perceived outer space as infinite for centuries, and since the observations of Edwin Hubble in the 1920s, scientists have studied phenomena that suggest the universe itself is expanding. However, as the title of Clay Moltz’s most recent book points out, the region of space most important to the economic and physical security of residents on Earth is increasingly viewed as far from infinite.

Meeting Growth Challenges Of Mexico Aerospace: The Queretaro Cluster, Monica Casalet

Space and Defense

Growing the Aerospace sector in Mexico requires multilevel agreement between original equipment manufacturers (OEMs), including foreign companies, and national and sub-national governments to stimulate programs and instruments for sector growth. In addition, space for local learning must be cultivated within a process of production organized hierarchically and highly regulated on the international level. The case of the Queretaro cluster is important due to the density of networks created, extensive public-private collaboration, and the emergence of specialized institutions to train and shape highly skilled (professionals and technicians) in the aerospace industry. Ultimately, there remains an important vacuum to fill in the …

Brazil Space: Military Dependency And The Case Of The Geostationary Satellite Of Defense And Strategic Communications, Gills Vilar Lopes

Space and Defense

In Brazil, there has been no transition model of space capabilities promoted by the military sphere (especially the Brazilian Air Force) for nurturing the civil one (Brazilian Space Agency). Drawing upon official documents and legislation as primary sources, the case study of the Geostationary Satellite of Defense and Strategic Communications (SGDC) is analyzed in light of the space strategic sector. Main factors that impede the PEB are related to military-technological dependence and poor resource management, with draconian budget cuts and projects canceled before having achieved realistic milestones.

Attack On The Brain: Neurowars And Neurowarfare, Armin Krishnan

Space and Defense

Is neurotechnology leading nation-states toward a new domain of war? Neuroscience is on the verge of deciphering the human brain. As a result, brains will become a part of the battlefield against which attacks will be directed. As neuroscientist James Giordano argued: “the brain is the next battlespace.” It is foreseeable that this will have tremendous implications for warfare and could amount to a true military revolution in the sense of military historian Williamson Murray: it would completely change the characteristics of conflict, as well as transform state and society.

Editor's Note Volume 9 No. 1, Damon Coletta

Space and Defense

No abstract provided.

Table Of Contents Volume 9 No. 1, Space And Defense

Space and Defense

No abstract provided.

Front Matter Volume 9 No. 1, Space And Defense

Space and Defense

No abstract provided.

Stereoscopic-Based Mass Properties Estimation For Warhead Fragments, Alessia Nocerino, Katharine Larsen, Riccardo Bevilacqua, Elisabetta L. Jerome

Student Works

FRAGMENTATION characteristics such as spatial distribution, number of fragments, fragment velocity, and fragment mass can be used to characterize the lethality of a fragmenting weapon or any metal cased explosive [1,2]. However, most warhead tests and evaluations are limited to static arena testing, where fragment characteristics must be collected by hand. Recently, stereoscopic imaging techniques have been added to static arena tests. Using this method, position tracks can be collected for each fragment, and then velocity information can be found. This paper proposes a method to estimate the mass and moment of inertia using data collected by a stereoscopic imaging …

Determining The Preparedness Of Nursing Programs And Faculty For The Next Generation Nclex-Rn, Heather Hartness

ATU Theses and Dissertations 2021 - Present

Fifty-two nursing faculty from ADN (Associate Degree Nursing) and BSN (Bachelor of Science in Nursing) programs in the state of Arkansas were surveyed to examine the preparedness resources and interventions to prepare for the Next Generation NCLEX-RN (NGN) and to explore the perceptions of nursing faculty on their readiness to teach critical thinking, clinical judgment, and their competency with NGN item writing. A quantitative cross-sectional descriptive design was used for this study utilizing a self-created survey. The survey revealed 40% of participants felt adequately prepared with item writing, and 35% reported feeling adequately prepared to test using the new NGN …

Foundation Of The Superhypersoft Set And The Fuzzy Extension Superhypersoft Set: A New Vision, Florentin Smarandache

Neutrosophic Systems with Applications

We introduce for the first time the SuperHyperSoft Set and the Fuzzy and Fuzzy Extension SuperHyperSoft Set. Through a theorem, we prove that the SuperHyperSoft Set is composed from many HyperSoft Sets.