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Articles 391 - 420 of 2423

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Towards Explainable Ai Using Attribution Methods And Image Segmentation, Garrett J. Rocks Jan 2023

Towards Explainable Ai Using Attribution Methods And Image Segmentation, Garrett J. Rocks

Honors Undergraduate Theses

With artificial intelligence (AI) becoming ubiquitous in a broad range of application domains, the opacity of deep learning models remains an obstacle to adaptation within safety-critical systems. Explainable AI (XAI) aims to build trust in AI systems by revealing important inner mechanisms of what has been treated as a black box by human users. This thesis specifically aims to improve the transparency and trustworthiness of deep learning algorithms by combining attribution methods with image segmentation methods. This thesis has the potential to improve the trust and acceptance of AI systems, leading to more responsible and ethical AI applications. An exploratory …

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Journal Of The Arkansas Academy Of Science Volume 77, Academy Editors Jan 2023

Journal Of The Arkansas Academy Of Science Volume 77, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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A Framework Of Critical Success Factors For Implementation Of Industry 4.0 In Aerospace And Defense Industries, Lina Khan Jan 2023

A Framework Of Critical Success Factors For Implementation Of Industry 4.0 In Aerospace And Defense Industries, Lina Khan

Electronic Theses and Dissertations, 2020-2023

The fourth industrial revolution, or Industry 4.0, is essential to the success of Aerospace and Defense (A&D) organizations as it showcases the ability to adapt, innovate, and remain competitive. Industry 4.0 technologies such as cyber-physical systems (CPS), big data, cognitive computing, smart factories, connected manufacturing, and the Internet of Things (IoT) focus on revolutionizing manufacturing through embedding digital and physical systems, with the goal to maximize the desired output(s) while using minimal resources. Although there are numerous advantages, there are challenges associated with implementation of these complex systems. This doctoral research investigates the critical factors needed for successful implementation of …

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The Influence Of Tropical Atlantic Sea-Surface Temperatures And The North Atlantic Subtropical High During The Maya Droughts, Derek K. Gibson, Jonathan Obrist-Farner, Brooke A. Birkett, Jason H. Curtis, Melissa A. Berke, Peter M.J. Douglas, Prudence M. Rice, Jeremy Maurer Jan 2023

The Influence Of Tropical Atlantic Sea-Surface Temperatures And The North Atlantic Subtropical High During The Maya Droughts, Derek K. Gibson, Jonathan Obrist-Farner, Brooke A. Birkett, Jason H. Curtis, Melissa A. Berke, Peter M.J. Douglas, Prudence M. Rice, Jeremy Maurer

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The frequency and duration of Late-Holocene hydrologic extremes in northern Guatemala were investigated using multiple sedimentological and geochemical proxies preserved in a sediment core collected from Lake Petén Itzá. A general trend of increasing aridity in the Maya Lowlands during the past 2000 years was punctuated by several multidecadal- to centennial-scale drought events recorded in the Petén Itzá sediments. In particular, the period spanning the Maya Terminal Classic Period and the Medieval Climate Anomaly (MCA), between 800 and 1300 CE, was marked by several extreme droughts and included the driest conditions of the past 2000 years between 950 and 1100 …

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Demonstration Of High Detoxification Efficiency Of Glassy Polymer-Metal Hydroxide Composites Toward Chemical Warfare Agent Simulants, Peter O. Aina, Sukanta K. Mondal, Joshua Costain, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Demonstration Of High Detoxification Efficiency Of Glassy Polymer-Metal Hydroxide Composites Toward Chemical Warfare Agent Simulants, Peter O. Aina, Sukanta K. Mondal, Joshua Costain, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

The design and development of polymeric composites that can effectively capture and destruct toxic chemicals with a fast detoxification rate is of high importance for protecting the military, first responders, and civilians. Here we report the synthesis and assessment of zirconium hydroxide (Zr (OH)4)-incorporated Ultem, Matrimid, and PIM-1 composites for detoxification of dimethyl 4-nitrophenylphosphonate (DMNP), as a type G toxic nerve agent simulant. Maintaining homogeneity, three different loadings (8, 20, 30 wt %) of Zr (OH)4 were incorporated into the polymers, and the thin films of composite materials were developed for subsequent hydrolysis tests. Our results indicated that increasing the …

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The Need For International Ai Activities Monitoring, Parviz Partow-Navid, Ludwig Slusky Jan 2023

The Need For International Ai Activities Monitoring, Parviz Partow-Navid, Ludwig Slusky

Journal of International Technology and Information Management

This paper focuses primarily on the need to monitor the risks arising from the dual-use of Artificial Intelligence (AI). Dual-use AI technology capability makes it applicable for defense systems and consequently may pose significant security risks, both intentional and unintentional, with the national and international scope of effects. While domestic use of AI remains the prerogative of individual countries, the unregulated and nonmonitored use of AI with international implications presents a specific concern. An international organization tasked with monitoring potential threats of AI activities could help defuse AI-associated risks and promote global cooperation in developing and deploying AI technology. The …

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Patch-Wise Training With Convolutional Neural Networks To Synthetically Upscale Cfd Simulations, John P. Romano, Alec C. Brodeur, Oktay Baysal Jan 2023

Patch-Wise Training With Convolutional Neural Networks To Synthetically Upscale Cfd Simulations, John P. Romano, Alec C. Brodeur, Oktay Baysal

Mechanical & Aerospace Engineering Faculty Publications

This paper expands the authors’ prior work[1], which focuses on developing a convolutional neural network (CNN) model capable of mapping time-averaged, unsteady Reynold’s-averaged Navier-Stokes (URANS) simulations to higher resolution results informed by time-averaged detached eddy simulations (DES). The authors present improvements over the prior CNN autoencoder model that result from hyperparameter optimization, increased data set augmentation through the adoption of a patch-wise training approach, and the predictions of primitive variables rather than vorticity magnitude. The training of the CNN model developed in this study uses the same URANS and DES simulations of a transonic flow around several NACA 4-digit airfoils …

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Human Factors Training Implications For Urban Air Mobility Operations, Kendall Carmody, Bhoomin Chauhan, Maureen Namukasa, Vivek Sharma, Gervaughn Berkel, Yarisse Adorno, Meredith Carroll Jan 2023

Human Factors Training Implications For Urban Air Mobility Operations, Kendall Carmody, Bhoomin Chauhan, Maureen Namukasa, Vivek Sharma, Gervaughn Berkel, Yarisse Adorno, Meredith Carroll

Aeronautics Faculty Publications

Advanced air mobility (AAM), of which urban air mobility (UAM) is a subset, signifies an exciting and advanced mode of air transportation that combines novel aircraft configurations with progressive levels of automation to offer convenient and efficient modes of air transportation (Mitchell et al., 2021). The design of these innovative aircraft will utilize advanced autonomous systems and are proposed to minimize pilot training requirements and scale operations (Mathur et al., 2019; Thipphavong, 2018). Further, the operational context of UAM will be characterized by low-altitude flights, single pilot operations, unique weather phenomena such as mechanical turbulence, and novel propulsion systems. Early …

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Architecting Future Multi-Modal Networks Coexistence, Generalization & Testbeds, Maqsood Ahamed Abdul Careem Jan 2023

Architecting Future Multi-Modal Networks Coexistence, Generalization & Testbeds, Maqsood Ahamed Abdul Careem

Legacy Theses & Dissertations (2009 - 2024)

Next Generation (xG) wireless networks are poised to revolutionize the way people, devices, data and processes sense, communicate, interact, and collectively enable a wide range of emerging applications, ranging from smart cities, connected healthcare, and advanced vehicular communication to extended reality. To facilitate this seamless interoperability, these networks need to evolve to accommodate and integrate multiple modalities in communication/ sensing technologies and spectrum, heterogeneous networks, trends in signal-processing (statistical, AI-driven, and distributed systems), centralized and distributed architectures, and device/ network hardware resources. However, to cater to the high-target metrics and wide-range of applications, these multi-modal networks must efficiently address multi-faceted …

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Underwater Communication Acoustic Transducers: A Technology Review, Laila Shams, Tian-Bing Xu, Zhongqing Su (Ed.), Branko Glisic (Ed.), Maria Pina Limongelli (Ed.) Jan 2023

Underwater Communication Acoustic Transducers: A Technology Review, Laila Shams, Tian-Bing Xu, Zhongqing Su (Ed.), Branko Glisic (Ed.), Maria Pina Limongelli (Ed.)

Mechanical & Aerospace Engineering Faculty Publications

This paper provides a comprehensive review on transducer technologies for underwater communications. The popularly used communication transducers, such as piezoelectric acoustic transducers, electromagnetic acoustic transducers, and acousto-optic devices are reviewed in detail. The reasons that common air communication technologies are invalid die to the differences between the media of air and water are addresses. Because of the abilities to overcome challenges the complexity of marine environments, piezoelectric acoustic transducers are playing the major underwater communication roles for science, surveillance, and Naval missions. The configuration and material properties of piezoelectric transducers effects on signal output power, beamwidth, amplitude, and other properties …

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Commentary On Healthcare And Disruptive Innovation, Hilary Finch, Affia Abasi-Amefon, Woosub Jung, Lucas Potter, Xavier-Lewis Palmer Jan 2023

Commentary On Healthcare And Disruptive Innovation, Hilary Finch, Affia Abasi-Amefon, Woosub Jung, Lucas Potter, Xavier-Lewis Palmer

Electrical & Computer Engineering Faculty Publications

Exploits of technology have been an issue in healthcare for many years. Many hospital systems have a problem with “disruptive innovation” when introducing new technology. Disruptive innovation is “an innovation that creates a new market by applying a different set of values, which ultimately overtakes an existing market” (Sensmeier, 2012). Modern healthcare systems are historically slow to accept new technological advancements. This may be because patient-based, provider-based, or industry-wide decisions are tough to implement, giving way to dire consequences. One potential consequence is that healthcare providers may not be able to provide the best possible care to patients. For example, …

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Improving Social Bot Detection Through Aid And Training, Ryan Kenny, Baruch Fischhoff, Alex Davis, Casey I. Canfield Jan 2023

Improving Social Bot Detection Through Aid And Training, Ryan Kenny, Baruch Fischhoff, Alex Davis, Casey I. Canfield

Engineering Management and Systems Engineering Faculty Research & Creative Works

Objective: We test the effects of three aids on individuals' ability to detect social bots among Twitter personas: a bot indicator score, a training video, and a warning. Background: Detecting social bots can prevent online deception. We use a simulated social media task to evaluate three aids. Method: Lay participants judged whether each of 60 Twitter personas was a human or social bot in a simulated online environment, using agreement between three machine learning algorithms to estimate the probability of each persona being a bot. Experiment 1 compared a control group and two intervention groups, one provided a bot indicator …

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Biocybersecurity And Deterrence: Hypothetical Rwandan Considerations, Issah Samori, Gbadebo Odularu, Lucas Potter, Xavier-Lewis Palmer Jan 2023

Biocybersecurity And Deterrence: Hypothetical Rwandan Considerations, Issah Samori, Gbadebo Odularu, Lucas Potter, Xavier-Lewis Palmer

Community & Environmental Health Faculty Publications

Digitalization and sustainability are popular words within modern disciplines as practitioners each look toward the future of their respective fields. Specifically for the African continent, which is making great strides in developmental targets, those two terms are central to core aspects of policy initiatives that may foster cooperation across its varied lands and nations. One of the underlying challenges that confront Africa is a lack of strong regional integration across socioeconomic and political programs; there is value in African regions having more regional connectedness. We assess the rate of regional integration and development in Africa and discuss how to alleviate …

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Convolutional-Neural-Network-Based Des-Level Aerodynamic Flow Field Generation From Urans Data, John P. Romano, Oktay Baysal, Alec C. Brodeur Jan 2023

Convolutional-Neural-Network-Based Des-Level Aerodynamic Flow Field Generation From Urans Data, John P. Romano, Oktay Baysal, Alec C. Brodeur

Mechanical & Aerospace Engineering Faculty Publications

The present paper culminates several investigations into the use of convolutional neural networks (CNNs) as a post-processing step to improve the accuracy of unsteady Reynolds-averaged Navier–Stokes (URANS) simulations for subsonic flows over airfoils at low angles of attack. Time-averaged detached eddy simulation (DES)-generated flow fields serve as the target data for creating and training CNN models. CNN post-processing generates flow-field data comparable to DES resolution, but after using only URANS-level resources and properly training CNN models. This document outlines the underlying theory and progress toward the goal of improving URANS simulations by looking at flow predictions for a class of …

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The Rayleigh Problem (Random Flights) Is Everywhere Redux, John E. Gray, Stephen R. Addison Jan 2023

The Rayleigh Problem (Random Flights) Is Everywhere Redux, John E. Gray, Stephen R. Addison

Journal of the Arkansas Academy of Science

The phase noise problem (or Rayleigh problem) occurs in all aspects of radar. It is an effect that a radar engineer or physicist always has to take into account as part of a design or in an attempt to characterize the physics of a problem such as reverberation. Normally, the mathematical difficulties of phase noise characterization are avoided by assuming the phase noise probability distribution function (PDF) is uniformly distributed, and the Central Limit Theorem (CLT) is invoked to argue that the superposition of relatively few random components obey the CLT and hence the superposition can be treated as a …

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Deep-Learning-Based Classification Of Digitally Modulated Signals Using Capsule Networks And Cyclic Cumulants, John A. Snoap, Dimitrie C. Popescu, James A. Latshaw, Chad M. Spooner Jan 2023

Deep-Learning-Based Classification Of Digitally Modulated Signals Using Capsule Networks And Cyclic Cumulants, John A. Snoap, Dimitrie C. Popescu, James A. Latshaw, Chad M. Spooner

Electrical & Computer Engineering Faculty Publications

This paper presents a novel deep-learning (DL)-based approach for classifying digitally modulated signals, which involves the use of capsule networks (CAPs) together with the cyclic cumulant (CC) features of the signals. These were blindly estimated using cyclostationary signal processing (CSP) and were then input into the CAP for training and classification. The classification performance and the generalization abilities of the proposed approach were tested using two distinct datasets that contained the same types of digitally modulated signals, but had distinct generation parameters. The results showed that the classification of digitally modulated signals using CAPs and CCs proposed in the paper …

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Social-Engineering, Bio-Economies, And Nation-State Ontological Security: A Commentary, Brandon Griffin, Keitavius Alexander, Xavier-Lewis Palmer, Lucas Potter Jan 2023

Social-Engineering, Bio-Economies, And Nation-State Ontological Security: A Commentary, Brandon Griffin, Keitavius Alexander, Xavier-Lewis Palmer, Lucas Potter

Electrical & Computer Engineering Faculty Publications

Biocybersecurity is an evolving discipline that aims to identify the gaps and risks associated with the convergence of Biology (the science of life and living organisms) and cybersecurity (the science, study, and theory of cyberspace and cybernetics) to protect the bioeconomy. The biological industries’ increased reliance on digitization, automation, and computing power has resulted in benefits for the scientific community, it has simultaneously multiplied the risk factors associated with industrial espionage and the protection of data both commercial and proprietary. The sensitive and potentially destructive power of this data and its access inherently poses a risk to the national and …

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Implications Of Cyberbiosecurity In Advanced Agriculture, Simone Stephen, Keitavius Alexander, Lucas Potter, Xavier-Lewis Palmer Jan 2023

Implications Of Cyberbiosecurity In Advanced Agriculture, Simone Stephen, Keitavius Alexander, Lucas Potter, Xavier-Lewis Palmer

Electrical & Computer Engineering Faculty Publications

The world is currently undergoing a rapid digital transformation sometimes referred to as the fourth industrial revolution. During this transformation, it is increasingly clear that many scientific fields are not prepared for this change. One specific area is agriculture. As the sector which creates global food supply, this critical infrastructure requires detailed assessment and research via newly developed technologies (Millett et al, 2019; Peccoud et al, 2018) . Despite its fundamental significance to modern civilization, many aspects of industrial agriculture have not yet adapted to the digital world. This is evident in the many vulnerabilities currently present within agricultural systems, …

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A Reflection Of Typology And Verification Flaws In Consideration Of Biocybersecurity/Cyberbiosecurity: Just Another Gap In The Wall, Luke Potter, Kim Mossberg, Xavier Palmer Jan 2023

A Reflection Of Typology And Verification Flaws In Consideration Of Biocybersecurity/Cyberbiosecurity: Just Another Gap In The Wall, Luke Potter, Kim Mossberg, Xavier Palmer

Electrical & Computer Engineering Faculty Publications

Verification is central to any process in a functional and enduring cyber-secure organization. This verification is how the validity or accuracy of a state of being is assessed (Schlick, 1936; Balci, 1998). Conversely, breakdown in verification procedures is core to the interruption of normal operations for an organization. A key problem for organizations that utilize biology as an interlock within their systems is that personnel lack sufficient ability to verify all practically relevant biological information for procedures such as a nurse logging a blood draw, or a molecular biology technician preparing agar to culture microbes for study. This has several …

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Task Assignment And Path Planning Of Multiple Unmanned Aerial Vehicles Using Integer Linear Programming, Imran Saeed Mirza Jan 2023

Task Assignment And Path Planning Of Multiple Unmanned Aerial Vehicles Using Integer Linear Programming, Imran Saeed Mirza

Chulalongkorn University Theses and Dissertations (Chula ETD)

วิทยานิพนธ์ฉบับนี้นำเสนอสูตรโปรแกรมเชิงเส้นจำนวนเต็มเพื่อการมอบหมายงานและการวางแผนเส้นทางให้กับอากาศยานไร้คนขับหลายลำกลุ่มโดรนจะได้รับมอบหมายให้เยี่ยมภารกิจให้ครบทุกเป้าหมายและเดินทางกลับไปยังตำแหน่งเริ่มต้นโดยมีเป้าหมายให้ได้ผลรวมของระยะทางที่โดรนทุกตัวเดินทางมีค่าน้อยที่สุดในขณะเดียวกันไม่อนุญาตให้มีทัวร์ย่อยใดๆเพื่อให้ได้ผลลัพธ์ที่มีประสิทธิภาพมากที่สุดมีการทดลองทดสอบเพื่อตรวจสอบความถูกต้องของสูตรที่ได้นำเสนอโดยใช้จำนวนโดรนและจำนวนงานที่หลากหลายผลการทดสอบแสดงให้เห็นว่าการเพิ่มจำนวนโดรนโดยทั่วไปสามารถช่วยลดระยะทางรวมและลดระยะเวลาในการทำภารกิจให้เสร็จสิ้นได้ข้อดีของวิธีที่เสนอคือให้ผลเฉลยที่เหมาะสุดแต่ใช้เวลาในการคำนวณเพื่อค้นหาผลเฉลยก็นานด้วยดังนั้นจึงได้ทำการทดลองโดยกำหนดจำนวนโดรนและภาระงานที่ขนาดแตกต่างกันจากการทดสอบโดยใช้คอมพิวเตอร์โน้ตบุ๊กที่มีหน่วยประมวลผลเพนเทียม10หน่วยความจำแรม8GBและหน่วยความจำเอสเอสดีขนาด256GBพบว่าระบบที่มีงานไม่เกิน27การหาผลเฉลยเหมาะสมที่สุดทำได้ภายในไม่กี่นาทีโดยไม่ขึ้นกับจำนวนโดรนที่ใช้งานแต่สำหรับงานจำนวนมากที่เกินขีดจำกัดนี้จะไม่สามารถได้ผลเฉลยแม้ว่าจะใช้เวลาจำลองไปแล้วเกินหนึ่งชั่วโมงก็ตาม

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Fault Diagnosis Of Hydraulic Power System For Coal Mine Tunnel Drilling Rig Based On T-S Fuzzy Fault Tree, Liu Ruojun, Zhang Youzhen, Yao Ke Dec 2022

Fault Diagnosis Of Hydraulic Power System For Coal Mine Tunnel Drilling Rig Based On T-S Fuzzy Fault Tree, Liu Ruojun, Zhang Youzhen, Yao Ke

Coal Geology & Exploration

In view of the problems of fuzzy logic relation between the elements of the system, the polymorphism of fault mode, and the difficulty in obtaining the fault probability as a result of the complication of the hydraulic power system for coal mine tunnel drilling rig, a fault diagnosis method of hydraulic power system for coal mine tunnel drilling rig based on Takagi-Sugeno (T-S) fuzzy tree was proposed to overcome the limitations of traditional fault tree in fault diagnosis and analysis of the complex electromechanical hydraulic equipment. The method could timely and accurately obtain the fault information of equipment, and to …

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Research On Complex Combat Network Dynamic Evolution Based On Information Entropy, Lianyi Zhang, Xisheng Shen, Duzheng Qing, Han Zhang, Min Zhou, Xifu Wang Dec 2022

Research On Complex Combat Network Dynamic Evolution Based On Information Entropy, Lianyi Zhang, Xisheng Shen, Duzheng Qing, Han Zhang, Min Zhou, Xifu Wang

Journal of System Simulation

Abstract: Network-centric warfare, distributed and decentralized command and control gradually replace separately the traditional platform-centric warfare and centralized command and control, and information has become a combat capability. Based on the new information weapon equipment system operation loop, a complex combat network model based on information entropy is constructed, and the combat capability measurement method is proposed. On the basis of the combat capability upgrade being the network driving force, the dynamic evolution rule of the complex combat network is designed and the preferential evolution and stochastic evolution models are constructed. According to a typical system combat example, the influence …

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Modeling And Analysis Of Unmanned Aerial Vehicle System Leveraging Systems Modeling Language (Sysml), Niamat Ullah I Hossain, Mostafa Lutfi, Ifaz Ahmed, Aditya Akundi, Daniel Cobb Dec 2022

Modeling And Analysis Of Unmanned Aerial Vehicle System Leveraging Systems Modeling Language (Sysml), Niamat Ullah I Hossain, Mostafa Lutfi, Ifaz Ahmed, Aditya Akundi, Daniel Cobb

Informatics and Engineering Systems Faculty Publications

The use of unmanned aerial vehicles (UAVs) has seen a significant increase over time in several industries such as defense, healthcare, and agriculture to name a few. Their affordability has made it possible for industries to venture and invest in UAVs for both research and commercial purposes. In spite of their recent popularity; there remain a number of difficulties in the design representation of UAVs, including low image analysis, high cost, and time consumption. In addition, it is challenging to represent systems of systems that require multiple UAVs to work in cooperation, sharing resources, and complementing other assets on the …

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Formation And Interrogation Of A Modeling Excel Database For Sorbent Preconcentrate With Gc/Ms, Lisa Caravello Dec 2022

Formation And Interrogation Of A Modeling Excel Database For Sorbent Preconcentrate With Gc/Ms, Lisa Caravello

Chemical and Biological Engineering ETDs

Volatile organic compounds (VOCs) are of great interest and the subject of much research, as they can be used in various applications. Preconcentrating this class of analytes is necessary as they can be elusive with simple sampling techniques. VOCs are often captured using sorbents in thermal desorption tubes as preconcentrates prior to analysis, commonly gas chromatography mass spectroscopy (GCMS). There are gaps in knowledge in behavior of materials used as sorbents i.e., if they will retain an analyte of interest appropriately. In this research I seek to eliminate speculation and unknown variables of analyte and sorbent combinations by creating a …

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Development Of Alternative Air Filtration Materials And Methods Of Analysis, Ivan Philip Beckman Dec 2022

Development Of Alternative Air Filtration Materials And Methods Of Analysis, Ivan Philip Beckman

Theses and Dissertations

Clean air is a global health concern. Each year more than seven million people across the globe perish from breathing poor quality air. Development of high efficiency particulate air (HEPA) filters demonstrate an effort to mitigate dangerous aerosol hazards at the point of production. The nuclear power industry installs HEPA filters as a final line of containment of hazardous particles. Advancement air filtration technology is paramount to achieving global clean air. An exploration of analytical, experimental, computational, and machine learning models is presented in this dissertation to advance the science of air filtration technology. This dissertation studies, develops, and analyzes …

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Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach, Asmaa Chakir Dec 2022

Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach, Asmaa Chakir

Theses and Dissertations

Scramjet engines are key for sustained hypersonic flights. Analytic models play a critical role in the preliminary design of a scramjet engine configuration. The objective of this research is to develop and validate a quasi-1D model for the scramjet engine encompassing inlet, isolator and combustor, to evaluate the impact of flight conditions and design parameters on the engine functionality. The model is developed assuming isentropic flow in the inlet with a single turn; modified Fanno-flow equations in the isolator that account for the area change of the core flow; and the combustor is modeled using Heiser-Pratt equations accounting for the …

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Integration Of Hadfield Steel Into Modern Body Armor, Jason T. Fridlund Dec 2022

Integration Of Hadfield Steel Into Modern Body Armor, Jason T. Fridlund

ME 4133/6133 Mechanical Metallurgy

The increased lethality of recently fielded projectiles mandates a proportional escalation in armor performance. Recent advancements in ceramic technologies have allowed designers to incorporate harder but more brittle materials into hard armor designs to defeat yet more capable penetrating projectiles. Ceramics suffer from the feature of shattering, however, even when impacted by threats below their design parameters. While this shattering mechanism is used effectively to dissipate energy from high-energy rifle projectiles, it is wasted on low-energy projectiles, and can result in easily damaged lifesaving gear, both of which are undesirable in combat. In contrast, steel body armor has been used …

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Developmental Evaluation Of The B-1b Aircraft, Jonathon Malycke Dec 2022

Developmental Evaluation Of The B-1b Aircraft, Jonathon Malycke

Theses and Dissertations

The purpose of this test was to perform a Developmental Phase IIA evaluation of the B-1B Lancer for the land-based, long-range, all-weather ground attack mission. One two-hour ground evaluation, one simulator and one flight totaling 7.5 hours was conducted under daylight, visual meteorological conditions from Dyess Air Force Base (AFB) in Abilene, Texas (337th Test and Evaluation Squadron). All test objectives were completed except the low altitude flight evaluation, landing pattern operations, and AFCS operations due to weather, maintenance and time constraints. The test aircraft was representative of a production B-1B aircraft and included a Sniper Targeting Pod and a …

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Iot In Smart Communities, Technologies And Applications., Muhammad Zaigham Abbas Shah Syed Dec 2022

Iot In Smart Communities, Technologies And Applications., Muhammad Zaigham Abbas Shah Syed

Electronic Theses and Dissertations

Internet of Things is a system that integrates different devices and technologies, removing the necessity of human intervention. This enables the capacity of having smart (or smarter) cities around the world. By hosting different technologies and allowing interactions between them, the internet of things has spearheaded the development of smart city systems for sustainable living, increased comfort and productivity for citizens. The Internet of Things (IoT) for Smart Cities has many different domains and draws upon various underlying systems for its operation, in this work, we provide a holistic coverage of the Internet of Things in Smart Cities by discussing …

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Operational And Cost Analysis Of A Leo Radar-Based Satellite Constellation, Kyle O. Norbert Dec 2022

Operational And Cost Analysis Of A Leo Radar-Based Satellite Constellation, Kyle O. Norbert

Theses and Dissertations

This thesis presents a methodology to assess the ability of a Low-Earth Orbit (LEO) satellite constellation to successfully accomplish the GMTI mission in a cost-effective fashion. A simulation model was developed to test the coverage performance of 512 unique constellation designs. Significant factors were revealed by developing regression models that revealed the most critical constellation trade-offs on measures of performance. A Value-Focused Thinking (VFT) approach was applied to assign weights to a broad range of measures of performance from which the Pareto distribution on a cost-capability plot revealed cost-effectiveness. A novel measure of performance was developed and analyzed that accounted …

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