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Characterization Of An Omega Type Bi-Anisotropic Material, Moriel Gindi Mar 2024

Characterization Of An Omega Type Bi-Anisotropic Material, Moriel Gindi

Theses and Dissertations

A theory is presented for the extraction of the complete set of material parameters for a bi-anisotropic sample consisting of conductive omega-type particles governed by the mm21′ point-group symmetry. A rectangular-to-square wave-guide can be used to obtain the required measurements by allowing three distinct orientations of the material. The focus of this work is to develop the appropriate theory detailing the derivation of how the material parameters are extracted from the measurements in an analytical methodology that is similar in manner to the well-known Nicolson-Ross-Weir (NRW) algorithm.


Optimizing Deployment Kit, Introducing Acceptance Threshold, Saleh A. Alshuhri Mar 2024

Optimizing Deployment Kit, Introducing Acceptance Threshold, Saleh A. Alshuhri

Theses and Dissertations

This article addresses the optimization of a specialized deployment kit crucial for air force operations, emphasizing the need for rapid and efficient aircraft deployment. Through a comprehensive analysis of historical data, the study aims to streamline the kit's contents without compromising effectiveness. The research suggests a potential reduction of 7.8%, with an impressive 60.5% decrease if a minimal 5% threshold is deemed acceptable. While the primary focus is on air force deployment, the broader implications extend to military entities, such as armies and navies, highlighting the applicability of the findings in enhancing deployment efficiency across various defense sectors.


Techniques For Addressing Extreme Class Imbalance For Artificial Neural Networks Training, Colin W. Foley Mar 2024

Techniques For Addressing Extreme Class Imbalance For Artificial Neural Networks Training, Colin W. Foley

Theses and Dissertations

This research examined the class imbalance problem while training convolutional neural networks (CNN) by applying different techniques to combat this common issue. This research used a modified CIFAR-10 dataset along with a curated aerial image dataset. Methods covered included undersampling, oversampling, synthetic minority oversampling technique, Edited Nearest Neighbors and combinations of the aforementioned methods. This research found that undersampling methods tended to outperform oversampling methods. While undersampling methods showed a decrease in overall accuracy, the increase in minority class prediction performance was promising enough to warrant further investigation.


The Use Of Deep Learning And Transfer Learning In Complex Problems, Jacob S. Lang Mar 2024

The Use Of Deep Learning And Transfer Learning In Complex Problems, Jacob S. Lang

Theses and Dissertations

Deep neural networks and transfer learning show potential in addressing complex problems such as the Tower of Hanoi and knapsack problems. The primary aim is to examine how the use of deep neural networks and transfer learning can enhance the ability of artificial learning systems to generalize. Transfer learning plays a crucial role in machine learning, particularly in the domain of artificial neural networks, as it helps overcome the challenges associated with limited data, computational efficiency, and generalization. The methodology used in this research involves the creation of data sets for the Tower of Hanoi and knapsack problems. To predict …


Measuring The Comparative Performance Of Usaf Behavioral Health Clinic Operations: Emphasis On Capacity, Daniel L. Straw Mar 2024

Measuring The Comparative Performance Of Usaf Behavioral Health Clinic Operations: Emphasis On Capacity, Daniel L. Straw

Theses and Dissertations

This research examines the operations of behavioral health clinics in Air Force Continental United States facilities, with a focus on operational efficiency and capacity through Data Envelopment Analysis. Most facilities operate near capacity, demonstrating efficient resource usage, but concerns arise with the potential of increased demand. Days-to-care and leakage are identified as major sources of inefficiency, suggesting that addressing these issues can enhance operations and reduce costs. The study also explores the impact of COVID-19 on care delivery.


Evaluating United States Air Force Installation Water Security, Michael L. Berg Mar 2024

Evaluating United States Air Force Installation Water Security, Michael L. Berg

Theses and Dissertations

Water shortage at Mountain Home Air Force Base in the last decade ignited the need for an assessment of relative water security risk across United States Air Force installations. Current evaluation methods often differ from actual conditions suggesting a need to categorize security across the enterprise for multiple discrete locations. Indicator-based approaches for characterizing water security are common in academic literature but have little methodological consensus and have rarely been applied to discrete areas spread across geographically separated locations with diverse climates. Using a two-stage analytical hierarchy process and normalized utility functions, water security at 30 installations across the continental …


Artificial Intelligence And Perception: An Empirical Study, Anthony J. Neil Mar 2024

Artificial Intelligence And Perception: An Empirical Study, Anthony J. Neil

Theses and Dissertations

This thesis investigates the impact of adjusting artificial intelligence explainability levels’ outputs on user perception. The overarching study extends within the Explainable Artificial Intelligence (XAI) domain. It examines a spectrum of variables, including performance, cognizance, familiarity, transparency, system bias, and the overall impact of AI, to understand their collective and individual effects that enable effective professional use in an organization. The study aims to illuminate the relationship between the degree of explainability provided by large language models such as ChatGPT, Bard, and Bing AI and the performance of these models when tasked with XAI adjustments.


Estimating Stimulated Raman Scattering Noise In Cwdm O-Band Channels Induced By Two Classical Dwdm Sources In A Quantum Network Fiber Segment, Kurt T. Spranger Ii Mar 2024

Estimating Stimulated Raman Scattering Noise In Cwdm O-Band Channels Induced By Two Classical Dwdm Sources In A Quantum Network Fiber Segment, Kurt T. Spranger Ii

Theses and Dissertations

The purpose of this research is to estimate the stimulated Raman scattering noise induced in CWDM O-band channels by two DWDM classical sources in a terrestrial quantum optical network containing classical and quantum optical signal coexistence in the same fiber segment. A use case is defined and analyzed which extracts a single fiber segment from a notional Bell state measurement found in a notional terrestrial quantum network. A stimulated Raman scattering noise model is employed in a Python simulation to estimate and rank-order the five O-band channels with the least amount of relative induced stimulated Raman scattering noise when given …


Deploying Field-Capable Genome Sequencing: Human Performance Considerations Under Various Personal Protective Equipment Ensembles, Steven A. Torres Mar 2024

Deploying Field-Capable Genome Sequencing: Human Performance Considerations Under Various Personal Protective Equipment Ensembles, Steven A. Torres

Theses and Dissertations

Field-portable genome sequencing enhances the Department of Defense's strategy for detecting biological threats, particularly in resource-limited environments. While current field-capable detection methods are effective, challenges in identifying emerging threats pose risks to personnel safety. As biotechnological advancements like portable nanopore genome sequencing can advance biological detection capabilities, the viability of conducting laboratory tasks under Mission-Oriented Protective Posture (MOPP) ensembles lacks sufficient data. This research assesses the effectiveness of tools like pipettes, centrifuges, vortexes, and nanopore sequencing within a MOPP ensemble. Novice participants were utilized to explore the extension of this capability, and they completed tasks in three conditions: Fatigues, Laboratory …


Generalized Characterization Of Biaxial Media Using Ultra-Wideband Multi-Static Focused Beam System With Polarimetric Calibration, Jeffrey P. Massman Mar 2024

Generalized Characterization Of Biaxial Media Using Ultra-Wideband Multi-Static Focused Beam System With Polarimetric Calibration, Jeffrey P. Massman

Theses and Dissertations

Novel metamaterial and metasurface realizations provide unique control of the electromagnetic wave dispersion but present many challenges for accurate constitutive parameter extraction. One measurement approach commonly employed is a freespace non-destructive focus beam system. Modern implementations are configured with multi-static dual-polarized capabilities for characterizing complex materials and offer many advantages by enabling ultra-wideband sampling, multiple measurement degrees of freedom and larger sample sizes. Practical electromagnetic material characterization of complex bianisotropic media requires the advancement of wave propagation analysis and calibration schemes. This research focuses on generalized biaxial media characterization and multi-static focused beam system metrology with polarimetric calibration schemes and …


Life Cycle Analysis Of Mobile Nuclear Reactor Compared To Other Alternative Fuels In Indopacom, Maria J. Hurtado Mar 2024

Life Cycle Analysis Of Mobile Nuclear Reactor Compared To Other Alternative Fuels In Indopacom, Maria J. Hurtado

Theses and Dissertations

Energy is an item that makes the military vulnerable as it is something that they depend on the most which can have negative impacts. Mobile nuclear reactors are gaining the interest of many leaders in the military as a viable option of a potential alternative fuel source. There are many positives in utilizing mobile nuclear reactors in terms of environmental impacts and feasibility of transport. Studies have shown that mobile nuclear reactors can produce very low or negligible carbon emissions during operations. The focus of this thesis is to determine the environmental impacts of nuclear reactors, logistical requirements, and determine …


Utilization Of The System Engineering Design Process To Design And Test A Low-Cost Infectious Aerosol Control Mechanism For Patient Aeromedical Evacuation, Sara Shaghaghi Mar 2024

Utilization Of The System Engineering Design Process To Design And Test A Low-Cost Infectious Aerosol Control Mechanism For Patient Aeromedical Evacuation, Sara Shaghaghi

Theses and Dissertations

The aeromedical evacuation of military patients is a critical component of care for Armed Forces members. The Air Force’s ability to transport patients relies on the technology and systems available. A vital transport responsibility is keeping the patient and medical personnel safe during transport. The historical and legacy systems provide reliable transport mechanisms for the Armed Forces’ patients infected with high-level biological agents, but drawbacks must be considered. This dissertation will discuss the development, conceptual design, and initial evaluation of a new low-cost, litter-mounted patient transport system, Biological-Mitigation in Patient Transport (B-MIPT), using the “V” model of the system engineering …


Advanced Oxidation Of Methyl Tert Butyl Ether With Ultraviolet Light Emitting Diodes, Aaron R. Neal Mar 2024

Advanced Oxidation Of Methyl Tert Butyl Ether With Ultraviolet Light Emitting Diodes, Aaron R. Neal

Theses and Dissertations

Methyl Tert-Butyl Ether (MTBE) is a volatile, soluble, organic compound introduced to gasoline within the United States as a fuel oxygenator in 1979. MTBE is a common groundwater pollutant due to its high water solubility and resistance to bio-degradation; it commonly infiltrates groundwater sources via leaking underground storage tanks or fuel spills. This research employed ultraviolet light emitting diodes (UV-LEDs) and hydrogen peroxide (H2O2) induced advanced oxidation process (AOP) to treat MTBE contaminated water at the bench scale. Using four H2O2:MTBE molar peroxide ratios (100:1, 200:1, 400:1, 500:1), MTBE degradation was induced …


Spectroscopic Characterization Of Trivalent Holmium In Liyf4 And Bay2F8 Crystals, Vivian R. Hedberg Mar 2024

Spectroscopic Characterization Of Trivalent Holmium In Liyf4 And Bay2F8 Crystals, Vivian R. Hedberg

Theses and Dissertations

Yttrium-fluoride crystals doped with trivalent holmium are promising laser gain media for mid-infrared laser systems. To accurately model laser systems, a complete optical characterization of the laser gain medium is required. The key modeling parameters were obtained by a spectroscopic investigation of Ho3+ in LiYF4 and BaY2F8 crystal hosts. Several important mid-infrared laser transitions were characterized at nominal Ho3+ ion concentrations of 10-30 at.%. Polarized emission cross-sections were determined from the fluorescence spectra using the Füchtbauer-Ladenburg method. Polarized absorption cross-sections were obtained using the Integral Reciprocity method. The upper-state lifetimes were measured at room …


The Professional Constructor, Full Issue, Volume 49, Number 01 Mar 2024

The Professional Constructor, Full Issue, Volume 49, Number 01

The Professional Constructor

No abstract provided.


Statistical Reliability Estimation Of Space Launch Vehicles, Brooke N. Wagenblast Mar 2024

Statistical Reliability Estimation Of Space Launch Vehicles, Brooke N. Wagenblast

Theses and Dissertations

Space launch vehicle reliability is imperative to understand since launch vehicles are crucial in getting payloads into space for a hopefully successful mission. This thesis examines the reliability of commercial, civil, and military space launch vehicles through trend analysis and a variety of statistical methods. Data sets obtained from the Seradata database are analyzed for trends by looking at data subsets including launch date, launch country, final mission orbit, section (commercial, civil or military), launch vehicle family and failed subsystem. First-level Bayesian analysis and mean success rates are performed, primarily split up by launch vehicle family and total launches, and …


A Bayesian Approach For Lifetime Modeling And Prediction With Multi-Type Group-Shared Missing Covariates, Hao Zeng, Xuxue Sun, Kuo Wang, Yuxin Wen, Wujun Si, Mingyang Li Feb 2024

A Bayesian Approach For Lifetime Modeling And Prediction With Multi-Type Group-Shared Missing Covariates, Hao Zeng, Xuxue Sun, Kuo Wang, Yuxin Wen, Wujun Si, Mingyang Li

Engineering Faculty Articles and Research

In the field of reliability engineering, covariate information shared among product units within a specific group (e.g., a manufacturing batch, an operating region), such as operating conditions and design settings, exerts substantial influence on product lifetime prediction. The covariates shared within each group may be missing due to sensing limitations and data privacy issues. The missing covariates shared within the same group commonly encompass a variety of attribute types, such as discrete types, continuous types, or mixed types. Existing studies have mainly considered single-type missing covariates at the individual level, and they have failed to thoroughly investigate the influence of …


Consumers' Acceptance To Buy And Dispose Of Recycling Textile Products, Roa Alsayed Feb 2024

Consumers' Acceptance To Buy And Dispose Of Recycling Textile Products, Roa Alsayed

Theses and Dissertations

The textile industry is the second most polluting worldwide, following food manufacturing. It is one of the industries that is rarely scrutinized in the Middle East and North Africa (MENA) region. This work analyzes the fashion industry from the perspective of consumer attitudes towards the purchase and disposal of clothing, and their behavior with regards to old garments. The study was conducted in Saudi Arabia and Egypt, two countries that achieved similar results in the fashion industry. The methodology is divided into three phases. First, the manuscript begins with a review of topics such as sustainability, consumer behavior in the …


Influence Of Alkali Metal Cations On The Oxygen Reduction Activity Of Pt5Y And Pt5Gd Alloys, Kun-Ting Song, Alexandra Zagalskaya, Christian M. Schott, Peter M. Schneider, Batyr Garlyyev, Vitaly Alexandrov, Aliaksandr S. Bandarenka Feb 2024

Influence Of Alkali Metal Cations On The Oxygen Reduction Activity Of Pt5Y And Pt5Gd Alloys, Kun-Ting Song, Alexandra Zagalskaya, Christian M. Schott, Peter M. Schneider, Batyr Garlyyev, Vitaly Alexandrov, Aliaksandr S. Bandarenka

Department of Chemical and Biomolecular Engineering: Faculty Publications

Electrolyte species can significantly influence the electrocatalytic performance. In this work, we investigate the impact of alkali metal cations on the oxygen reduction reaction (ORR) on active Pt5Gd and Pt5Y polycrystalline electrodes. Due to the strain effects, Pt alloys exhibit a higher kinetic current density of ORR than pure Pt electrodes in acidic media. In alkaline solutions, the kinetic current density of ORR for Pt alloys decreases linearly with the decreasing hydration energy in the order of Li+ > Na+ > K+ > Rb+ > Cs+, whereas Pt shows the opposite trend. To gain …


Research And Optimization Of Yolo-Based Method For Automatic Pavement Defect Detection, Hui Yao, Yaning Fan, Xinyue Wei, Yanhao Liu, Dandan Cao, Zhanping You Feb 2024

Research And Optimization Of Yolo-Based Method For Automatic Pavement Defect Detection, Hui Yao, Yaning Fan, Xinyue Wei, Yanhao Liu, Dandan Cao, Zhanping You

Michigan Tech Publications

According to the latest statistics at the end of 2022, the total length of highways in China has reached 5.3548 million kilometers, with a maintenance mileage of 5.3503 million kilometers, accounting for 99.9% of the total maintenance coverage. Relying on inefficient manual pavement detection methods is difficult to meet the needs of large-scale detection. To tackle this issue, experiments were conducted to explore deep learning-based intelligent identification models, leveraging pavement distress data as the fundamental basis. The dataset encompasses pavement micro-cracks, which hold particular significance for the purpose of pavement preventive maintenance. The two-stage model Faster R-CNN achieved a mean …


2024 Monitoring Program Update For Five Corners Intersection, Tisbury, Ma, Daniel Macadam, James J. Houle Feb 2024

2024 Monitoring Program Update For Five Corners Intersection, Tisbury, Ma, Daniel Macadam, James J. Houle

UNH Stormwater Center

The UNH Stormwater Center has conducted three years of monitoring of the stormwater catch basin at the intersection in Tisbury, MA known as “Five Corners.” The intersection is known to all residents and many visitors to the island for its frequent flooding. The goal of this project was to gather empirical data, observe, and characterize the rainfall events to quantify the conditions which result in the flooding at the intersection. The monitoring was performed with level loggers in the catch basin to measure the water level within the catch basin as well as when it exceeded the street level (flooding). …


Occurrence Mechanism, Environment And Dynamic Evolution Of Gas And Water In Deep Coal Seams, Li Yong, Xu Lifu, Liu Yu, Wang Ziwei, Gao Shuang, Ren Ci Feb 2024

Occurrence Mechanism, Environment And Dynamic Evolution Of Gas And Water In Deep Coal Seams, Li Yong, Xu Lifu, Liu Yu, Wang Ziwei, Gao Shuang, Ren Ci

Coal Geology & Exploration

Accurately understanding of the occurrence states, relative content, and distribution characteristics of gas - water under deep conditions has important guiding significance for efficient exploration and development of coalbed methane (CBM). Based on the theoretical model, molecular simulation and systematic analysis of gas-water, the occurrence states of gas-water in coal seam is clarified, and the boundary and dynamic evolution process of gas-water dynamic migration and accumulation are revealed. Considering the coal - water interface interaction, the mobility and occurrence states of water, the coalbed water can be divided into movable water (gravity water and capillary water), bound water (adsorbed water, …


Log-Linear Dynamic Inversion Control With Provable Safety Guarantees In Lie Groups, Li-Yu Lin, James Goppert, Inseok Hwang Feb 2024

Log-Linear Dynamic Inversion Control With Provable Safety Guarantees In Lie Groups, Li-Yu Lin, James Goppert, Inseok Hwang

School of Aeronautics and Astronautics Faculty Publications

In this article, we use the derivative of the exponential map to derive the exact evolution of the logarithm of the tracking error for mixed-invariant systems, a class of systems capable of describing rigid body tracking problems in Lie groups. In addition, we design a log-linear dynamic inversion-based control law to remove the nonlinearities due to spatial curvature and enhance the robustness of the controller. We apply linear matrix inequalities to bound the tracking error given a bounded disturbance amplified by the distortion matrix and leverage the tracking error bound to create flow pipes. To demonstrate the usefulness of our …


Endoscopic Hyperspectral Imaging System To Discriminate Tissue Characteristics In Tissue Phantom And Orthotopic Mouse Pancreatic Tumor Model, Na Eun Mun, Thi Kim Chi Tran, Dong Hui Park, Jin Hee Im, Jae Il Park, Thanh Dat Le, Young Jin Moon, Seong-Young Kwon, Su Woong Yoo Feb 2024

Endoscopic Hyperspectral Imaging System To Discriminate Tissue Characteristics In Tissue Phantom And Orthotopic Mouse Pancreatic Tumor Model, Na Eun Mun, Thi Kim Chi Tran, Dong Hui Park, Jin Hee Im, Jae Il Park, Thanh Dat Le, Young Jin Moon, Seong-Young Kwon, Su Woong Yoo

Faculty, Staff and Student Publications

In this study, we developed an endoscopic hyperspectral imaging (eHSI) system and evaluated its performance in analyzing tissues within tissue phantoms and orthotopic mouse pancreatic tumor models. Our custom-built eHSI system incorporated a liquid crystal tunable filter. To assess its tissue discrimination capabilities, we acquired images of tissue phantoms, distinguishing between fat and muscle regions. The system underwent supervised training using labeled samples, and this classification model was then applied to other tissue phantom images for evaluation. In the tissue phantom experiment, the eHSI effectively differentiated muscle from fat and background tissues. The precision scores regarding fat tissue classification were …


Ai-Based Investigation And Mitigation Of Rain Effect On Channel Performance With Aid Of A Novel 3d Slot Array Antenna Design For High Throughput Satellite System, Ali M. Al-Saegh, Fatma Taher, Taha A. Elwi, Mohammad Alibakhshikenari, Bal S. Virdee, Osama Abdullah, Salahuddin Khan, Patrizia Livreri, Abdulmajeed Al-Jumaily, Mohamed Fathy Abo Sree, Arkan Mousa Majeed, Lida Kouhalvandi, Zaid A. Abdul Hassain, Giovanni Pau Feb 2024

Ai-Based Investigation And Mitigation Of Rain Effect On Channel Performance With Aid Of A Novel 3d Slot Array Antenna Design For High Throughput Satellite System, Ali M. Al-Saegh, Fatma Taher, Taha A. Elwi, Mohammad Alibakhshikenari, Bal S. Virdee, Osama Abdullah, Salahuddin Khan, Patrizia Livreri, Abdulmajeed Al-Jumaily, Mohamed Fathy Abo Sree, Arkan Mousa Majeed, Lida Kouhalvandi, Zaid A. Abdul Hassain, Giovanni Pau

All Works

Rain attenuation poses a significant challenge for high-throughput communication systems. In response, this paper introduces an artificial intelligence (AI) model designed for predicting and mitigating rain-induced impairments in high-throughput satellite (HTS) to land channels. The model is based on three AI algorithms developed using 3D antenna design to characterize, analyze, and mitigate rain-induced attenuation, optimizing channel quality specifically in the United Arab Emirates (UAE). The study evaluates various parameters, including rain-specific attenuation, effective slant path through rain, rain-induced attenuation, signal carrier-to-noise ratio, and symbol error rate, for five conventional modulation schemes: Quadrature Phase-Shift Keying (QPSK), 8-Phase Shift Keying (8-PSK), 16-Quadrature …


Detecting Substance Use Disorder Using Social Media Data And Dark Web: Time And Knowledge Aware Study, Usha Lokala, Orchid Chetia Phukan, Triyasha Ghosh Dastidar, Francois Lamy, Raminta Daniulaityte, Amit Sheth Feb 2024

Detecting Substance Use Disorder Using Social Media Data And Dark Web: Time And Knowledge Aware Study, Usha Lokala, Orchid Chetia Phukan, Triyasha Ghosh Dastidar, Francois Lamy, Raminta Daniulaityte, Amit Sheth

Faculty Publications

Opioid and substance misuse is rampant in the United States today, with the phenomenon known as the "opioid crisis". The relationship between substance use and mental health has been extensively studied, with one possible relationship being: substance misuse causes poor mental health. However, the lack of evidence on the relationship has resulted in opioids being largely inaccessible through legal means. This study analyzes the substance use posts on social media with opioids being sold through crypto market listings. We use the Drug Abuse Ontology, state-of-the-art deep learning, and knowledge-aware BERT-based models to generate sentiment and emotion for the social media …


Association Of Bovine Arch Anatomy With Incident Stroke After Transcatheter Aortic Valve Replacement, Gerardo V. Lo Russo, Hasan S. Alarouri, Abdulah Al-Abcha, Brennan Vogl, Abdulah Mahayni, Agata Sularz, Hoda Hatoum, Jeremy Collins, Juan A. Crestanello, Mohamad Alkhouli Feb 2024

Association Of Bovine Arch Anatomy With Incident Stroke After Transcatheter Aortic Valve Replacement, Gerardo V. Lo Russo, Hasan S. Alarouri, Abdulah Al-Abcha, Brennan Vogl, Abdulah Mahayni, Agata Sularz, Hoda Hatoum, Jeremy Collins, Juan A. Crestanello, Mohamad Alkhouli

Michigan Tech Publications

BACKGROUND: Acute ischemic stroke complicates 2 % to 3 % of transcatheter aortic valve replacements (TAVRs). This study aimed to identify the aortic anatomic correlates in patients after TAVR stroke. METHODS AND RESULTS: This is a single-center, retrospective study of patients who underwent TAVR at the Mayo Clinic between 2012 and 2022. The aortic arch morphology was determined via a manual review of the pre-TAVR computed tomography images. An "a priori" approach was used to select the covariates for the following: (1) the logistic regression model assessing the association between a bovine arch and periprocedural stroke (defined as stroke within …


Modeling At The Nanometric Scale Of Interfacial Defects Of A Semiconductor Heterostructure In The Isotropic And Anisotropic Cases For The Study Of The Influence Of Stresses, Ahmed Boussaha, Rafik Makhloufi, Rachid Benbouta, Mourad Brioua Feb 2024

Modeling At The Nanometric Scale Of Interfacial Defects Of A Semiconductor Heterostructure In The Isotropic And Anisotropic Cases For The Study Of The Influence Of Stresses, Ahmed Boussaha, Rafik Makhloufi, Rachid Benbouta, Mourad Brioua

Emirates Journal for Engineering Research

This work aims to determine the effect of stresses caused by dislocation networks placed at the interface of a semiconductor heterostructure of the thin GaAs/Si system. In this case, we use a mathematical modeling by Fourier series expansion to numerically simulate the stresses for the two cases of isotropic and anisotropic elasticity in order to predict the mechanical behavior of the heterostructure in the presence of interfacial dislocations while respecting well-defined stress boundary conditions. The elastic stress relaxation is reached for a layer thickness threshold of the GaAs deposit on the Si substrate not exceeding 5 nm.


Hybrid Hydrolysis And Fermentation Of Prosopis Juliflora Pods For Biohydrogen Production By Dark Fermentation, Gayathri G Feb 2024

Hybrid Hydrolysis And Fermentation Of Prosopis Juliflora Pods For Biohydrogen Production By Dark Fermentation, Gayathri G

Theses and Dissertations

The rapid consumption of fossil fuels has resulted in the energy crisis and many environmental issues, including air pollution and the greenhouse effect. Hydrogen is the independent source of the highest energy content, with 122 KJ g-1. Biohydrogen produced from lignocellulosic biomass (LCB) is an excellent alternative fuel for its cleanability, renewability and sustainability. Biohydrogen production from dark fermentation using lignocellulosic biomass provides low cost and a sustainable pathway to utilize a vast amount of waste.

Dark fermentation has considerable potential for hydrogen production because it does not require sunlight, allowing for full-time operation and minimizing bioreactor complexity. The major …


A Systematic Survey On 5g And 6g Security Considerations, Challenges, Trends, And Research Areas, Paul Scalise, Matthew Boeding, Hamid Sharif, Joseph Delloiacovo, John Reed Feb 2024

A Systematic Survey On 5g And 6g Security Considerations, Challenges, Trends, And Research Areas, Paul Scalise, Matthew Boeding, Hamid Sharif, Joseph Delloiacovo, John Reed

Department of Electrical and Computer Engineering: Faculty Publications

With the rapid rollout and growing adoption of 3GPP 5thGeneration (5G) cellular services, including in critical infrastructure sectors, it is important to review security mechanisms, risks, and potential vulnerabilities within this vital technology. Numerous security capabilities need to work together to ensure and maintain a sufficiently secure 5G environment that places user privacy and security at the forefront. Confidentiality, integrity, and availability are all pillars of a privacy and security framework that define major aspects of 5G operations. They are incorporated and considered in the design of the 5G standard by the 3rd Generation Partnership Project (3GPP) with the goal …