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Differential Game-Based Defensive Architecture Study Employing Ground-Based Interceptors, Stephen T. Zittrouer Mar 2022

Differential Game-Based Defensive Architecture Study Employing Ground-Based Interceptors, Stephen T. Zittrouer

Theses and Dissertations

A study of defensive architectures for combating hypersonic glide vehicles (HGVs) via interception with a ground-based interceptor (GBI) is presented. Pursuit-evasion differential games are formulated for numerical simulation of the interception engagements. A one-sided optimal control problem wherein the evader HGV is optimized and the pursuer GBI employs a suboptimal proportional navigation control strategy is solved. The solution space is characterized by varying the pursuer initial velocity advantage relative to the evader. A two-sided optimal control problem in which both players behave optimally is solved via the semi-direct collocation with nonlinear programming (semiDCNLP) method. The resulting state and control trajectories …


A Proposed Mission Assurance Framework For University Cubesat Programs, Mitchell R. Thomas Mar 2022

A Proposed Mission Assurance Framework For University Cubesat Programs, Mitchell R. Thomas

Theses and Dissertations

The low cost, small form factor, and use of Commercial-Off-The-Shelf components make CubeSats an ideal platform for university use given their unique constraints. Since 2000, roughly 55% of CubeSats developed by universities fail to meet mission goals. Mission assurance, which is used to increase confidence in mission success, is based around traditional government programs, and does not provide an adequate road map for universities. Leaving them without specific guidance in tailoring mission assurance activities to operate within their constraints. This paper adapts these traditional practices to develop a baseline mission assurance framework for university CubeSat programs.


Simulating Autonomous Cruise Missile Swarm Behaviors In An Anti-Access Area Denial (A2ad) Environment, Kyle W. Goggins Mar 2022

Simulating Autonomous Cruise Missile Swarm Behaviors In An Anti-Access Area Denial (A2ad) Environment, Kyle W. Goggins

Theses and Dissertations

The increasingly sophisticated anti-access area denial (A2AD) threat imposed by the modern integrated air defense system (IADS), coupled with the decreasingly potent advantage provided by high-end stealth platforms, has prompted Air Force senior leaders to invest in radically changing the nature of air power for the year 2030 and beyond. A prominent element of this new vision is weapon swarming, which aims to address this challenge by overwhelming the IADS with huge numbers of low-cost, attritable aerial assets emboldened by autonomous capabilities. This research proposes a framework for classifying the different levels of autonomous capability along three independent dimensions—namely ability …


Deep Learning Techniques To Estimate 3d Position In Stereoscopic Imagery, Jonathan I. Nicholson Mar 2022

Deep Learning Techniques To Estimate 3d Position In Stereoscopic Imagery, Jonathan I. Nicholson

Theses and Dissertations

Current AAR efforts utilize machine vision algorithms to estimate the pose of a receiver aircraft. However, these algorithms are dependent on several conditions such as the availability of precise 3D aircraft models; the accuracy of the pipeline significantly degrades in the absence of high-quality information given beforehand. We propose a deep learning architecture that estimates the 3D position of an object based on stereoscopic imagery. We investigate the use of both machine learning techniques and neural networks to directly regress the 3D position of the receiver aircraft. We present a new position estimation framework that is based on the differences …


Narrative Analysis Of Open-Source Social Media Activity In The Indopacom Aor, Aaron K. Glenn Mar 2022

Narrative Analysis Of Open-Source Social Media Activity In The Indopacom Aor, Aaron K. Glenn

Theses and Dissertations

Emotion classification can be a powerful tool to derive narratives from social media data. Recurrent Neural Networks (RNN) can meet or exceed the performance of state-of-the-art traditional machine learning techniques using exclusively open-source data and models. Specifically, these results show that RNN variants can produce more than an 8% gain in accuracy in comparison to Logistic Regression and SVM techniques and a 15% gain over Random Forest when using FastText embeddings. This research found a statistical significance in the performance of a single layer Bi-directional Long Short-Term Memory (Bi-LSTM) model over a 2-layer stacked Bi-LSTM model. This research also found …


The Cyber Wargame Commodity Course Of Action Automated Analysis Method, Alex Hoffendahl Mar 2022

The Cyber Wargame Commodity Course Of Action Automated Analysis Method, Alex Hoffendahl

Theses and Dissertations

In the modern operational landscape, strategic decisions are made and executed, under uncertain conditions, with many potential constraints and limited information. The end goal of these decisions is to minimize and mitigate the effect of adversarial threats, which may or may not act in line with previous assumptions. Wargaming is a powerful tool that allows for the practical implementation of theoretical knowledge into real-world scenarios, enhancing decision-makers critical thinking and problem solving skills. Furthermore, including cyber-effects in a wargame leads to a broader decision scope for an entire operation. This research aims to enhance the analytical capabilities and overall usability …


Understanding Logistics Airmen’S Risk Information Seeking And Processing During The Covid-19 Pandemic: The Role Of Organizational Meetings In An Extended Prism Framework, Christopher T. Price Mar 2022

Understanding Logistics Airmen’S Risk Information Seeking And Processing During The Covid-19 Pandemic: The Role Of Organizational Meetings In An Extended Prism Framework, Christopher T. Price

Theses and Dissertations

The purpose of this survey-based research was to understand how organizational workplace meetings surrounding the COVID-19 pandemic impacted logistics Airmen across the United States Air Force and subsequently played a role into their risk seeking behavior on social media. Specifically, this research tested an expanded Planned Information Risk Seeking Model with organizational meetings as an antecedent to determine if current meetings influenced an Airman's perceived behavioral control, attitude toward seeking, subjective norms, knowledge sufficiency an intentions to seek information regarding COVID-19.


Accelerating Transition To Production By Manufacturing Readiness Focus During Development, William K. Duncan Mar 2022

Accelerating Transition To Production By Manufacturing Readiness Focus During Development, William K. Duncan

Theses and Dissertations

The Department of Defense has adopted management tools, such as Manufacturing Readiness Levels (MRLs), which seek to address issues that have delayed the transition to production and delivery of deployment-ready systems. The MRL scale and assessment process institutes periodic reviews of products during the acquisition process. Specifically, MRLs provide a scale to measure, and importantly communicate, progress by evaluating and summarizing multiple aspects of product maturity. Unfortunately, issues are often identified during the periodic assessments which, if addressed earlier, would have further streamlined product delivery. The current research applies Model Based System Engineering tools to analyze and refine organizational structures …


Tools & Visualization Techniques Available To Support The Operations Manager, Kirk Michealson Feb 2022

Tools & Visualization Techniques Available To Support The Operations Manager, Kirk Michealson

Operations Management Presentations

Most organizations provide their employees the Microsoft Office Tools Suite with Excel. The University of Arkansas Master of Science in Operations Management (MSOM) Program has included Excel as a foundational aspect of the program for the last 7 years. In that time, Microsoft has increased the Excel capabilities dramatically. Simultaneously, business intelligence analytics interest has increased, and Tableau has been created as a visual analytics platform to help users see and understand data for modern business intelligence. As a result, to support the Operations Manager the MSOM Program has developed a new course to present the additional tools and visualization …


Addressing Underground, Unmanned Threats: A Case Study Of Gpr Detecting Illegal Objects At Nuclear Facilities And Enhancing Subterranean Physical Protection Systems, Md. Shamsul Huda Sohel, Mohammad Khan, Dr. Debashis Datta Feb 2022

Addressing Underground, Unmanned Threats: A Case Study Of Gpr Detecting Illegal Objects At Nuclear Facilities And Enhancing Subterranean Physical Protection Systems, Md. Shamsul Huda Sohel, Mohammad Khan, Dr. Debashis Datta

International Journal of Nuclear Security

In nuclear installations, any unmanned threat is unacceptable. Such threats are a major issue for the nuclear physical protection system (PPS). Although the PPS of a nuclear power plant (NPP) is well prepared to deal with threats above ground level, until now, a special PPS had never been developed for detecting and tackling underground threats. One example of such a threat is a weapon-carrying, unmanned object operated by remote. Using this technology, a terrorist could launch an attack and overcome security barriers. While a normal PPS would not detect the underground activities of a mobile object, a PPS using a …


Strong Laser Polarization Control Of Coherent Phonon Excitation In Van Der Waals Material Fe3Gete2, Yu Gong, Ming Hu, Nico Harris, Zhonghua Yang, Ti Xie, Alem Teklu, Narayanan Kuthirummal, Jacob Koenemann, Xianghan Xu, Sang-Wook Cheong, Will Mcloud, Cheng Gong Feb 2022

Strong Laser Polarization Control Of Coherent Phonon Excitation In Van Der Waals Material Fe3Gete2, Yu Gong, Ming Hu, Nico Harris, Zhonghua Yang, Ti Xie, Alem Teklu, Narayanan Kuthirummal, Jacob Koenemann, Xianghan Xu, Sang-Wook Cheong, Will Mcloud, Cheng Gong

Faculty Publications

Optical manipulation of coherent phonon frequency in two-dimensional (2D) materials could advance the development of ultrafast phononics in atomic-thin platforms. However, conventional approaches for such control are limited to doping, strain, structural or thermal engineering. Here, we report the experimental observation of strong laser-polarization control of coherent phonon frequency through time-resolved pump-probe spectroscopic study of van der Waals (vdW) materials Fe3GeTe2. When the polarization of the pumping laser with tilted incidence is swept between in-plane and out-of-plane orientations, the frequencies of excited phonons can be monotonically tuned by as large as 3% (~100 GHz). Our first-principles …


Surface Acoustic Wave (Saw) Sensors: Physics, Materials, And Applications, Debdyuti Mandal, Sourav Banerjee Jan 2022

Surface Acoustic Wave (Saw) Sensors: Physics, Materials, And Applications, Debdyuti Mandal, Sourav Banerjee

Faculty Publications

Surface acoustic waves (SAWs) are the guided waves that propagate along the top surface of a material with wave vectors orthogonal to the normal direction to the surface. Based on these waves, SAW sensors are conceptualized by employing piezoelectric crystals where the guided elastodynamic waves are generated through an electromechanical coupling. Electromechanical coupling in both active and passive modes is achieved by integrating interdigitated electrode transducers (IDT) with the piezoelectric crystals. Innovative meta-designs of the periodic IDTs define the functionality and application of SAW sensors. This review article presents the physics of guided surface acoustic waves and the piezoelectric materials …


Track Deception Modeling Method Based On Multi-Jammer Cooperation, Wang Rui, Xiangyang Li, Zhili Zhang, Hongguang Ma Jan 2022

Track Deception Modeling Method Based On Multi-Jammer Cooperation, Wang Rui, Xiangyang Li, Zhili Zhang, Hongguang Ma

Journal of System Simulation

Abstract: The false track generated by the jammer formation is an effective interference measure against networked radars. This paper starts from the basic principle of false track generation and presents the model of the measurement error of the radar for the false track and the control error of the jammer formation. It also presents an analysis of the effects of these errors on the false track. The effectiveness of the false track is further analyzed through the confrontation scenario between the rectangular front formation of a certain type of equipment and networked radars. The simulation results show that the false …


Improved Ant Colony Optimization Algorithm For Jamming Resource Allocation, Qingyun Wang, Dezhong Jiao, Shi Shuo, Genyan Peng, Junhua Sun, Yuxin Duan Jan 2022

Improved Ant Colony Optimization Algorithm For Jamming Resource Allocation, Qingyun Wang, Dezhong Jiao, Shi Shuo, Genyan Peng, Junhua Sun, Yuxin Duan

Journal of System Simulation

Abstract: Ant Colony Optimization (ACO) is a new intelligence optimization algorithm. When applied to jamming resource allocation, the velocity of convergence in optimization process is slow and the probability of obtaining the global optimal solution is low. In order to raise the efficiency of jamming resource allocation and the probability of getting global optimal solution, the attenuation factor is improved to a variable that changes according to the exponential function in optimization process. The attenuation factor is taken as a relatively small value in the initial search phase, and increases monotonically and exponentially as the number of iterations increases. Simulation …


Academic Year 2021-2022 Faculty Excellence Showcase, Afit Graduate School Of Engineering & Management, Graduate School Of Engineering And Management, Air Force Institute Of Technology Jan 2022

Academic Year 2021-2022 Faculty Excellence Showcase, Afit Graduate School Of Engineering & Management, Graduate School Of Engineering And Management, Air Force Institute Of Technology

AFIT Documents

No abstract provided.


Deepfakes: Ai Technology Of The Future, Hosanna Root Jan 2022

Deepfakes: Ai Technology Of The Future, Hosanna Root

Cybersecurity Undergraduate Research Showcase

Deepfakes technology’s danger stems from its ability to create realistic but fake synthesized media that people often identify as something that is real. With this powerful technology in the wrong hands, deepfakes can cause devastating havoc through information warfare, election campaign disruptions, and more, creating distrust in society. Disinformation is already rampant today, even without wide deployments of deepfakes, which is concerning given the fact that deepfakes’ nefarious full potentials are yet to be reached.


Anatomy Of An Internet Hijack And Interception Attack: A Global And Educational Perspective, Ben A. Scott, Michael N. Johnstone, Patryk Szewczyk Jan 2022

Anatomy Of An Internet Hijack And Interception Attack: A Global And Educational Perspective, Ben A. Scott, Michael N. Johnstone, Patryk Szewczyk

Annual ADFSL Conference on Digital Forensics, Security and Law

The Internet’s underlying vulnerable protocol infrastructure is a rich target for cyber crime, cyber espionage and cyber warfare operations. The stability and security of the Internet infrastructure are important to the function of global matters of state, critical infrastructure, global e-commerce and election systems. There are global approaches to tackle Internet security challenges that include governance, law, educational and technical perspectives. This paper reviews a number of approaches to these challenges, the increasingly surgical attacks that target the underlying vulnerable protocol infrastructure of the Internet, and the extant cyber security education curricula; we find the majority of predominant cyber security …


Future Needs Of The Cybersecurity Workforce, Connie Justice, Char Sample, Sin Ming Loo, Alex Ball, Clay Hampton Jan 2022

Future Needs Of The Cybersecurity Workforce, Connie Justice, Char Sample, Sin Ming Loo, Alex Ball, Clay Hampton

Electrical and Computer Engineering Faculty Publications and Presentations

Expected growth of the job market for cyber security professionals in both the US and the UK remains strong for the foreseeable future. While there are many roles to be found in cyber security, that vary from penetration tester to chief information security officer (CISO). One job of particular interest is security architect. The rise in Zero Trust Architecture (ZTA) implementations, especially in the cloud environment, promises an increase in the demand for these security professionals. A security architect requires a set of knowledge, skills, and abilities covering the responsibility for integrating the various security components to successfully support an …


The Heat Shock Protein 90 Inhibitor, At13387, Protects The Alveolo-Capillary Barrier And Prevents Hci-Induced Chronic Lung Injury And Pulmonary Fibrosis, Ruben M.L. Colunga Biancatelli, Pavel Solopov, Christiana Dimitropoulou, Betsy Gregory, Tierney Day, John D. Catravas Jan 2022

The Heat Shock Protein 90 Inhibitor, At13387, Protects The Alveolo-Capillary Barrier And Prevents Hci-Induced Chronic Lung Injury And Pulmonary Fibrosis, Ruben M.L. Colunga Biancatelli, Pavel Solopov, Christiana Dimitropoulou, Betsy Gregory, Tierney Day, John D. Catravas

Bioelectrics Publications

Hydrochloric acid (HCl) exposure causes asthma-like conditions, reactive airways dysfunction syndrome, and pulmonary fibrosis. Heat Shock Protein 90 (HSP90) is a molecular chaperone that regulates multiple cellular processes. HSP90 inhibitors are undergoing clinical trials for cancer and are also being studied in various pre-clinical settings for their anti-inflammatory and anti-fibrotic effects. Here we investigated the ability of the heat shock protein 90 (HSP90) inhibitor AT13387 to prevent chronic lung injury induced by exposure to HCl in vivo and its protective role in the endothelial barrier in vitro. We instilled C57Bl/6J mice with 0.1N HCl (2 µL/g body weight, intratracheally) and …


Remotely Piloted Aircraft C2 Latency During Air-To- Air Combat, David L. Thirtyacre Jan 2022

Remotely Piloted Aircraft C2 Latency During Air-To- Air Combat, David L. Thirtyacre

Publications

Remotely piloted aircraft command-and-control latency could play a significant role during beyond-line-of-sight engagements in future conflicts. As the Air Force prepares to use these systems and artificial intelligence in within-visual-range combat, it must understand the effects of latency, or missing sensor data, during a dogfight. Research indicates technology-based latency influences the engagement outcome geometry similar to a slow decision-making cycle foundational to the understanding of Boyd’s Observe, Orient, Decide, Act (OODA) Loop. This study adds depth to the theory illustrating technology-induced latency has a similar effect as slow human decision making resulting in lower performance. Therefore, when combined with the …


การกำหนดนโยบายบริหารเพื่อเพิ่มประสิทธิภาพการเตรียมอะไหล่คงคลังกรณีศึกษาโรงงานผลิตกรดอะมิโน, พรพัชร จิระเดชะ Jan 2022

การกำหนดนโยบายบริหารเพื่อเพิ่มประสิทธิภาพการเตรียมอะไหล่คงคลังกรณีศึกษาโรงงานผลิตกรดอะมิโน, พรพัชร จิระเดชะ

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้นำเสนอนโยบายการบริหารเพื่อเพิ่มประสิทธิภาพในการเตรียมอะไหล่คงคลังกรณีศึกษาโรงงานผลิตกรดอะมิโน ซึ่งมูลค่าอะไหล่คงคลังเฉลี่ยต่อปี มีแนวโน้มเพิ่มขึ้นจาก 8.3 ล้านบาท ปี พ.ศ. 2559 จนถึง 10.5 ล้านบาท ปี พ.ศ. 2564 ซึ่งสวนทางกับมูลค่าการเบิกใช้อะไหล่ที่มีมูลค่าน้อยลง จึงส่งผลให้อัตราหมุนเวียนอะไหล่มีค่าเฉลี่ยต่อปีอยู่ที่ 0.034 และ 0.102 ในปี พ.ศ. 2559 และปี พ.ศ. 2564 ตามลำดับ ซึ่งแสดงให้เห็นว่าอะไหล่ที่ถูกเก็บในคลังมากกว่าความต้องการ ส่งผลให้สูญเสียค่าใช้จ่ายในการเก็บสูง ดังนั้นการเพิ่มประสิทธิภาพในการเตรียมอะไหล่จะถูกพิจารณาการดำเนินงานผ่านนโยบายการตัดสินใจการเก็บอะไหล่ และปริมาณการเก็บคงคลัง โดยเริ่มต้นจากการนำเสนอเมทริกซ์การตัดสินใจการเก็บอะไหล่ ที่ต้องมีการประเมินความวิกฤติอะไหล่ผ่านเมทริกซ์ 1. Part/equipment critical 2. Supplier/lead-time 3. Failure modes and effects criticality analysis และ 4. Decision matrix จากนโยบายการตัดสินใจการเก็บอะไหล่สามารถช่วยตัดสินใจเก็บอะไหล่ที่มีความวิกฤตสูง ส่วนอะไหล่ที่มีความวิกฤตต่ำจะไม่ถูกตัดสินใจเก็บ จากผลการศึกษาพบว่าสามารถลดจำนวนรายการอะไหล่ที่ต้องจัดเก็บลงได้ 40% จากนั้นนำเสนอนโยบายการตัดสินใจปริมาณการเก็บอะไหล่ ด้วยนโยบาย Base stock ใหม่ โดยการพิจารณาโอกาสการเบิกใช้อะไหล่ผ่านการแจกแจงแบบปัวส์ซองแบบสะสม และผลการจำลองด้วยวิธีการมอนติคาร์โลทั้งหมด 30 ครั้ง พบว่ามูลค่าอะไหล่เฉลี่ยลดลง 68% และระดับอะไหล่ลดลง 60% ส่งผลให้มูลค่าคลังเฉลี่ยลดลงจาก 8.7 ล้านเหลือ 2.3 ล้านบาท และอัตราการหมุนเวียนอะไหล่เฉลี่ยเพิ่มขึ้นจาก 0.060 เป็น 0.220 โดยไม่มีอะไหล่ขาดมือ และผลการทดสอบนโยบายกับชุดข้อมูล ปี พ.ศ. 2563 – 2564 พบว่ามูลค่าอะไหล่เฉลี่ยลดลง 24 % และระดับอะไหล่ลดลง 19% โดยไม่มีอะไหล่ขาดมือ


The Amorphous Nature Of Hackers: An Exploratory Study, Kento Yasuhara, Daniel Walnycky, Ibrahim Baggili, Ahmed Alhishwan Jan 2022

The Amorphous Nature Of Hackers: An Exploratory Study, Kento Yasuhara, Daniel Walnycky, Ibrahim Baggili, Ahmed Alhishwan

Annual ADFSL Conference on Digital Forensics, Security and Law

In this work, we aim to better understand outsider perspectives of the hacker community through a series of situation based survey questions. By doing this, we hope to gain insight into the overall reputation of hackers from participants in a wide range of technical and non-technical backgrounds. This is important to digital forensics since convicted hackers will be tried by people, each with their own perception of who hackers are. Do cyber crimes and national security issues negatively affect people’s perceptions of hackers? Does hacktivism and information warfare positively affect people’s perception of hackers? Do individual personality factors affect one’s …


Mechanical Response Of Vartm Infused Frp Composites, Andrew Kenney Jan 2022

Mechanical Response Of Vartm Infused Frp Composites, Andrew Kenney

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mechanical Response of VARTM based FRP composites

Andrew Kenney

The United States Department of Transportation (USDOT) recently created two new design specification for rail tank cars. These new types of classification, DOT-117 and DOT-117R, are designed with additional safety precautions to prevent hazardous chemicals from leaking out in case of a derailment. Features such as a thicker outer steel wall, head shield, and top and bottom valve protections provide additional protection compared to the current DOT-113 tank cars at the cost of additional weight. The WVU-CFC proposes a multifunctional, composite jacket that could be used in place of current tank …


Effect Of Freestream Noise On Hypersonic Crossflow-Induced Boundary-Layer Transition, Andrew Bustard, Thomas J. Juliano, Harrison B. Yates, Mark Noftz, Joseph Jewell Jan 2022

Effect Of Freestream Noise On Hypersonic Crossflow-Induced Boundary-Layer Transition, Andrew Bustard, Thomas J. Juliano, Harrison B. Yates, Mark Noftz, Joseph Jewell

Publications

Between the windward and leeward rays, boundary-layer transition on cones at angle of attack in hypersonic flow is dominated by the crossflow instability [1, 2], wherein stationary and/or traveling crossflow vortices develop and can breakdown into turbulence [3]. Stationary crossflow modes are caused by surface roughness or any other steady forcing and produce disturbances that are fixed in place on the surface [3–6]. Stationary vortices create a generalized inflection point in the velocity profile that is inviscidly unstable [7]. This distorted mean flow develops secondary instabilities, whose growth and breakdown is one path to turbulence [8–10]. Traveling crossflow modes are …


Derivation, Exploration And Evaluation Of Non-Equiatomic High Entropy Alloys, Artashes Ter-Isahakyan Jan 2022

Derivation, Exploration And Evaluation Of Non-Equiatomic High Entropy Alloys, Artashes Ter-Isahakyan

Theses and Dissertations--Chemical and Materials Engineering

High-entropy alloys (HEAs) are a class of multicomponent alloys based on an innovative alloying strategy that employs multi-principle elements in relatively high concentrations. Commonly defined as alloys that contain at least five principal elements, each with a concentration between 5 and 35 at %. The term entropy refers to the excess configurational entropy associated with HEAs, which is thought to facilitate the formation of solid solutions. The design strategy results in vast compositional space for exploration and innovative potential triggering a renaissance in physical metallurgy. These alloys may have favorable properties compared to conventional dilute solid solutions, but their preeminent …


Conceptual Design Of Fuel Dumping System In Aircraft, Naveen M. Kumar Mr., Ravi A. Kannan Be., Magesh L Be., Praveen T. Kumar Be., Vijay K. Babu Me., Prashanth Radhakrishnan Be. Jan 2022

Conceptual Design Of Fuel Dumping System In Aircraft, Naveen M. Kumar Mr., Ravi A. Kannan Be., Magesh L Be., Praveen T. Kumar Be., Vijay K. Babu Me., Prashanth Radhakrishnan Be.

International Journal of Aviation, Aeronautics, and Aerospace

Airlines release the unburned jet fuel into the atmosphere to reduce the weight of aircraft before landing. Sometimes, aircraft reach a weight more than takeoff weight while departing from the airport. Therefore, the pilot follows the ATC comment to dump fuel into the atmosphere to reduce the aircraft's weight to avoid accidents. Due to fuel dumping, an airline faces fuel consumption, loss, and several diseases affect environmental pollutants, and living things. The total fuel consumption of commercial airlines worldwide in 2021 is 57 billion gallons. If jet fuel routinely hit the ground, it would pollute water and land and damage …


Understanding Structure/Process-Property Relationships To Optimize Development Lifecycle In Yttria-Stabilized Zirconia Aerogels For Thermal Management, Rebecca C. Walker Jan 2022

Understanding Structure/Process-Property Relationships To Optimize Development Lifecycle In Yttria-Stabilized Zirconia Aerogels For Thermal Management, Rebecca C. Walker

Theses and Dissertations

Aerogels are mesoporous materials with unique properties, including high specific surface area, high porosity, low thermal conductivity, and low density, increasing these materials’ effectiveness in applications such as catalyst supports, sorption media, and electrodes in solid oxide fuel cells. Zirconia (ZrO2) aerogels have special interest for high-temperature applications due to the high melting point of ZrO2 (2715°C) and stability between 600°C and 1000°C, where other aerogel systems often begin to sinter and densify. These properties and unique pore structure make zirconia aerogels advantageous as thermal management systems, especially in aeronautics and aerospace applications. However, to be effective …


Undersea Cables: The Ultimate Geopolitical Chokepoint, Bert Chapman Dec 2021

Undersea Cables: The Ultimate Geopolitical Chokepoint, Bert Chapman

FORCES Initiative: Strategy, Security, and Social Systems

This work provides historical and contemporary overviews of this critical geopolitical problem, describes the policy actors addressing this in the U.S. and selected other countries, and provides maps and information on many undersea cable work routes. These cables are chokepoints with one dictionary defining chokepoints as “a strategic narrow route providing passage through or to another region."


Modeling The Ballistic Limit Of Fragment Simulating Projectiles Impacting A36 Mild Steel Spaced Armor Configurations, Daniel H. Rios-Estremera Dec 2021

Modeling The Ballistic Limit Of Fragment Simulating Projectiles Impacting A36 Mild Steel Spaced Armor Configurations, Daniel H. Rios-Estremera

Theses and Dissertations

Terminal ballistics study multivariate behavior and aftermath of projectile and target interactions. Tests and models are often based on monolithic armors, however, layered and spaced armors are common in real world applications. Such configurations add complexities that require research to understand their effects on terminal ballistics. The ballistic limit velocity (V50) represents the speed where armor perforation probability is 50%. It is used for quantitative comparison of protection capabilities for different armors. This research studied the V50 of spaced and layered A36 steel armors against fragment simulating projectiles (FSPs). Four methods for estimating armor V50 were evaluated and compared to …


A Temporal Analysis Of The Microbiota And Biofouling Development On Artificial Substrates In The Port Everglades Inlet, Florida, Denise Swack Dec 2021

A Temporal Analysis Of The Microbiota And Biofouling Development On Artificial Substrates In The Port Everglades Inlet, Florida, Denise Swack

All HCAS Student Capstones, Theses, and Dissertations

A pilot project was deployed in Port Everglades Inlet, Florida that aimed to evaluate the biofilm composing the microbiome on ecologically engineered artificial substrates used to build Coastal Marine Infrastructure. In April of 2017, an Articulated Concrete Block Mattress comprised of an ecological engineered concrete substrate and a standard smooth surface control substrates were compared. This study will provide a profile on the microbiome community on artificial substrates within Port Everglades Inlet on bio-enhancing concrete-based solutions in our Coastal Marine Infrastructure. To study the microbial community, the 16s rRNA technology was used in Illumina’s high-throughput DNA sequencing. Samples were collected …