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2025

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An Entropy-Bounded, General, Model-Based Framework For Lossy Compression Of Sensor Data, Steven Thompson, Maciej Zawodniok Jan 2025

An Entropy-Bounded, General, Model-Based Framework For Lossy Compression Of Sensor Data, Steven Thompson, Maciej Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

In many industries, digital twinning has become an indispensable element of advanced technologies. However, digital twins are heavily reliant on extensive Internet of Things (IoT) sensor measurement data to function effectively. Consequently, data mining has become a lucrative endeavor, akin to gold rushes in the XIX century. However, the substantial volume of collected data often stresses the storage capacities for smaller to medium-sized enterprises, necessitating efficient compression techniques. Error-bound lossy compression offers substantial data reduction advantages, but introduces distortion that, when uncontrolled, can adversely affect analysis. This paper proposes an information optimization scheme that employs information entropy as a comprehensive …

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Deep Learning For Uav Classification: Impact Of Noise And Multipath Fading In Rf Signals, Prajoy Podder, Maciej Jan Zawodniok, Sanjay Kumar Madria Jan 2025

Deep Learning For Uav Classification: Impact Of Noise And Multipath Fading In Rf Signals, Prajoy Podder, Maciej Jan Zawodniok, Sanjay Kumar Madria

Electrical and Computer Engineering Faculty Research & Creative Works

The increasing presence of unmanned aerial vehicles (UAVs) raises serious security concerns, particularly regarding unauthorized drone operations. Recent U.S. security statistics report a sharp rise in unauthorized UAV activities, with the Federal Aviation Administration (FAA) receiving over 100 monthly reports of illegal drone operations near airports. In 2024 alone, Dedrone records 1.19 million unauthorized drone flights across major U.S. cities, highlighting the need for robust UAV detection and classification systems. In this work, a lightweight Convolutional Neural Network (CNN) model is proposed for RF-based UAV classification under noisy and multipath fading conditions. The proposed CNN consists of multiple convolutional blocks, …

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Active Microwave-Thermographic Signal Reconstruction, Logan M. Wilcox, Emma T. Bohannon, Kristen M. Donnell Jan 2025

Active Microwave-Thermographic Signal Reconstruction, Logan M. Wilcox, Emma T. Bohannon, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is a coupled electromagnetic (EM) and thermographic nondestructive testing and evaluation (NDT&E) technique. AMT utilizes a radiating EM source (e.g., an antenna) that induces dielectric/magnetic heating on a specimen under test (SUT) which is subsequently spatiotemporally imaged with an infrared (IR) camera. As all antennas have spatial variation in their radiated power density, a nonuniform thermal excitation results within (or on the surface of) the SUT. This nonuniform heating causes uncertainty in defect detection and has the potential to lead to false positives and/or negatives. To this end, thermographic signal reconstruction (TSR), a well-established thermographic signal …

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Aperture-Based Fss For Dielectric Thickness Sensing, Alexander Hook, Gage Donahue, Kristen M. Donnell Jan 2025

Aperture-Based Fss For Dielectric Thickness Sensing, Alexander Hook, Gage Donahue, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surfaces (FSSs) are planar arrays of patch- or aperture-based elements that have a particular transmissive or reflective response. As FSS performance is affected by changes in the local (to the FSS) environment, FSSs may be used to detect changes in strain, temperature, or nearby material (substructure) thickness, amongst other parameters. To this end, an aperture-based FSS can be considered as a sensor for substructure thickness monitoring for surface mounted sensing scenarios. An aperture-based design was selected due to its ability to operate in reflection mode (and hence a one-sided measurement) without the need for a conductive backplane. In …

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Dual Parameter Fss-Based Sensing For Structural Health Monitoring Applications, Swathi Muthyala Ramesh, Doyle T. Motes, Kristen M. Donnell Jan 2025

Dual Parameter Fss-Based Sensing For Structural Health Monitoring Applications, Swathi Muthyala Ramesh, Doyle T. Motes, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

frequency selective surfaces (FSSs) are periodic arrays of conductive elements or apertures that reflect and/or transmit incident electromagnetic energy. Their response depends on parameters, such as element shape, unit cell dimensions, dielectric properties, and the local environment, making them suitable for structural health monitoring (SHM) applications. This article presents a dual-parameter FSS-based sensor design capable of measuring small-scale uni-directional longitudinal strain (0%–0.5%) and temperature (23 ◦C–223 ◦C). The sensor integrates two-unit cells: 1) a patch-based cell on a thin substrate for strain sensing, offering enhanced strain transfer and superior sensitivity (~16–18 MHz/0.1%) and 2) a loop-based cell with a temperature-sensitive …

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Active Microwave-Thermographic Signal Reconstruction With Adaptive Polynomial Regression, Logan M. Wilcox, Alexander Hook, Emma T. Bohannon, Kristen M. Donnell Jan 2025

Active Microwave-Thermographic Signal Reconstruction With Adaptive Polynomial Regression, Logan M. Wilcox, Alexander Hook, Emma T. Bohannon, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is a coupled electromagnetic (EM) and thermographic nondestructive testing and evaluation (NDT&E) technique. AMT utilizes a radiating EM source (e.g., an antenna) that induces dielectric/magnetic heating on a specimen under test (SUT). The inspection surface of the SUT is imaged with an infrared (IR) camera over the inspection time. As the thermal excitation originates from a spatially varying radiated power density, a nonuniform thermal excitation results within (or on the surface of) the SUT that is directly related to this power density. This nonuniform heating causes uncertainty in defect detection and has the potential to lead …

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Enhancing Fiber Optic Interferometric Sensing With Microwave Photonics-Based Dispersion Fourier Transform And Integrated Magnitude–Phase Analysis, Chen Zhu, Ruimin Jie, Chenxi Huang, Jie Huang Jan 2025

Enhancing Fiber Optic Interferometric Sensing With Microwave Photonics-Based Dispersion Fourier Transform And Integrated Magnitude–Phase Analysis, Chen Zhu, Ruimin Jie, Chenxi Huang, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Fiber optic inline interferometers are widely used for high-precision sensing due to their sensitivity, compactness, and immunity to electromagnetic interference. Traditional optical spectral analysis methods suffer from limited dynamic range due to free spectral range (FSR) constraints, while microwave photonic filtering (MPF) techniques based on dispersion Fourier transform (DFT) provide an alternative by mapping optical signals into the radio frequency (RF) domain. However, conventional passband frequency tracking in MPF systems has limited sensitivity, and the recently demonstrated phase-based methods, though highly sensitive, are constrained by phase wrapping beyond 2π. In this work, we propose and experimentally demonstrate an integrated magnitude–phase …

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Anti-Jamming Attack Mixed Strategy For Formation Tracking Control Via Game-Theoretical Reinforcement Learning, Lei Xue, Bei Ma, Yongbao Wu, Jian Liu, Chaoxu Mu, Donald C. Wunsch Jan 2025

Anti-Jamming Attack Mixed Strategy For Formation Tracking Control Via Game-Theoretical Reinforcement Learning, Lei Xue, Bei Ma, Yongbao Wu, Jian Liu, Chaoxu Mu, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Communication plays a role in multi-UAV to perform formation tracking missions. In complex environments, UAV communication is often subject to jamming attacks, affecting the formation process. Therefore, studying the formation tracking control problem in jamming attacks is of great significance. Typically, the actions of the UAV consist of two fundamental modules: mobility strategy and communication strategy. In this paper, we design an anti-jamming attack mixed strategy for formation tracking control of the multi-UAV system. In practical scenarios, multi-UAV systems not only require the accomplishment of formation maneuvers but also necessitate effective mitigation of jamming attacks caused by other UAVs. Therefore, …

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Phase-Variation Microwave Resonator For Highly Sensitive Dynamic Sensing, Chen Zhu, Rex E. Gerald, Jie Huang Jan 2025

Phase-Variation Microwave Resonator For Highly Sensitive Dynamic Sensing, Chen Zhu, Rex E. Gerald, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

High-precision dynamic sensing is critical in fields, such as industrial automation, structural health monitoring, and environmental sensing, where real-time responses to minuscule changes can prevent system failures or optimize performance. In this work, we introduce and demonstrate a phase-variation coaxial cable resonator (CCR) as a highly sensitive sensor for dynamic sensing applications. As a proof of concept, a prototype device based on a custom-designed CCR is thoroughly investigated for dynamic displacement measurements, as displacement is a fundamental quantity essential to numerous applications. The sensor consists of two components: a static CCR device and a movable conducting plate. As the conducting …

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A Low-Frequency-Stable Higher-Order Isogeometric Discretization Of The Augmented Electric Field Integral Equation, Maximilian Nolte, Riccardo Torchio, Sebastian Schöps, Jürgen Dölz, Felix Wolf, Albert E. Ruehli Jan 2025

A Low-Frequency-Stable Higher-Order Isogeometric Discretization Of The Augmented Electric Field Integral Equation, Maximilian Nolte, Riccardo Torchio, Sebastian Schöps, Jürgen Dölz, Felix Wolf, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

This contribution investigates the connection between Iso geometric analysis (IGA) and integral equation (IE) methods for full-wave electromagnetic problems up to the low-frequency limit. The proposed spline-based IE method allows for an exact representation of the model geometry described in terms of nonuniform rational B-splines (NURBS) without meshing. This is particularly useful when high accuracy is required or when meshing is cumbersome, for instance, during the optimization of electric components. The augmented electric field IE (EFIE) is adopted, and the deflation method is applied, so the low-frequency breakdown is avoided. The extension to higher-order basis functions is analyzed and the …

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Aperiodically Intermittent Dynamic Event-Triggered Control For Predefined-Time Synchronization Of Stochastic Complex Networks, Lei Xue, Haoyu Zhou, Yongbao Wu, Jian Liu, Donald C. Wunsch Jan 2025

Aperiodically Intermittent Dynamic Event-Triggered Control For Predefined-Time Synchronization Of Stochastic Complex Networks, Lei Xue, Haoyu Zhou, Yongbao Wu, Jian Liu, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the problem of practical predefined-time synchronization in mean square (PTSMS) of stochastic complex networks (SCNs) is investigated through dynamic event-triggered control (E-TC). Different from the existing literature, this paper considers the dynamic E-TC in an a periodically intermittent control framework and employs the average control rate, which makes it easier to satisfy the conditions of the theorem. In comparison to existing finite-time and fixed-time synchronization, by introducing the time-varying function, it can be guaranteed that all states of SCNs achieve the practical PTSMS within a preset time without calculating the convergence time. Combined with stochastic analysis theory, …

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Discrimination Of Temperature And Strain By Characterizing Two Femtosecond Laser-Written Coincident Sapphire Fiber Bragg Gratings For Harsh Environment Applications, Farhan Mumtaz, Bohong Zhang, Koustav Dey, Jeffrey D. Smith, Ronald J. O'Malley, Jie Huang Jan 2025

Discrimination Of Temperature And Strain By Characterizing Two Femtosecond Laser-Written Coincident Sapphire Fiber Bragg Gratings For Harsh Environment Applications, Farhan Mumtaz, Bohong Zhang, Koustav Dey, Jeffrey D. Smith, Ronald J. O'Malley, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

In this study, two co-incident sapphire fiber Bragg gratings (SFBGs) were successfully inscribed utilizing a femtosecond (fs) laser to achieve a high fringe contrast interferogram. These two SFBGs employ a unique configuration, one parallel to the center axis, called p-SFBG, and the other forming an angle from the center-axis, called a-SFBG, allowing for simultaneous strain and temperature measurements with low crosstalk. As a proof of concept, p-SFBG and a-SFBG using line-by-line method are characterized, which are shorter in length (i.e., 1.5 mm), producing reflectivity of ~3dB. This effort demonstrates the use of two coincident SFBGs forming an angle of 2.29° …

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Simultaneous Measurement Of Early-Stage Corrosion And Strain Levels In Steel Rebar Based On Graphene Oxide-Coated Ncf-Fbg Fiber Optic Sensor, Fujian Tang, Baihe Qu, Hong Nan Li, Jie Huang Jan 2025

Simultaneous Measurement Of Early-Stage Corrosion And Strain Levels In Steel Rebar Based On Graphene Oxide-Coated Ncf-Fbg Fiber Optic Sensor, Fujian Tang, Baihe Qu, Hong Nan Li, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Rebar corrosion significantly reduces the lifespan of reinforced concrete structures. The value of rebar strain, especially for some key structural components, indicates the safety margin of structures. In this study, a graphene oxide (GO) coated no-core fiber-fiber Bragg grating (NCF-FBG) fiber optic sensor is proposed for simultaneously measuring strain values and early-stage corrosion of steel rebar for the first time. The impact of GO coating thickness on the monitoring sensitivity is considered. A setup was manufactured to simultaneously perform tension, optical, and corrosion tests. The strain was applied up to 1200 μϵ. The rebar corrosion was assessed using electrochemical method …

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An Extensive Analysis Of Match-Tracking Methods For Artmap, Niklas M. Melton, Leonardo Enzo Brito Da Silva, Donald C. Wunsch Jan 2025

An Extensive Analysis Of Match-Tracking Methods For Artmap, Niklas M. Melton, Leonardo Enzo Brito Da Silva, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This paper identifies and studies five match-tracking (MT) methods in the adaptive resonance theory (ART) literature and conducts a detailed comparative analysis of these in ARTMAP applications. We focus on model performance for each MT method with respect to time and space efficiency as well as classification accuracy. Experimental results indicate that one MT variant, used in ARTMAP applications for the first time in this work, provides significant improvements in computational efficiency: depending on the ARTMAP variant, it was able to achieve up to one order of magnitude reduction in both time and space requirements, albeit with a compromise in …

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Prescribed-Time Nash Equilibrium Seeking For Pursuit-Evasion Game Under Intermittent Control With Undirected/Directed Graph, Lei Xue, Jianfeng Ye, Yongbao Wu, Jian Liu, D. C. Wunsch Jan 2025

Prescribed-Time Nash Equilibrium Seeking For Pursuit-Evasion Game Under Intermittent Control With Undirected/Directed Graph, Lei Xue, Jianfeng Ye, Yongbao Wu, Jian Liu, D. C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This paper studies the prescribed-time Nash equilibrium (PTNE) seeking problem of the pursuit-evasion game (PEG) with second-order dynamics under the intermittent control (IC) strategy. To achieve Nash equilibrium (NE) in a user-defined prescribed-time, a time-varying high-gain function is incorporated into the design. The core challenge lies in applying IC to NE seeking, which complicates the convergence analysis and control design. To address this sticking point, we construct an auxiliary function and propose a Lyapunov function considering second-order dynamics to solve the PTNE seeking problem of PEG. Building upon the results for undirected graphs, we further extend our findings to directed …

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Large-Range And High-Sensitivity Displacement Sensing Based On Extrinsic Fabry-Perot Interferometer Assisted Microwave Photonic Filter, Shiyu Li, Ruimin Jie, Osamah Alsalman, Jie Huang, Chen Zhu Jan 2025

Large-Range And High-Sensitivity Displacement Sensing Based On Extrinsic Fabry-Perot Interferometer Assisted Microwave Photonic Filter, Shiyu Li, Ruimin Jie, Osamah Alsalman, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Displacement is a pivotal physical parameter, and advancements in displacement sensor technology have enabled the creation of a diverse array of physical and mechanical sensors through seamless integration with mechanical transducers. In this study, we introduce a displacement sensing technique leveraging an extrinsic Fabry-Perot interferometer (EFPI) assisted microwave photonic filter. By translating displacement-induced variations in the EFPI's optical reflection into peak frequency shifts within its frequency response, we achieve large-dynamic-range displacement measurements with outstanding signal quality and demodulation ease. Proof-of-concept demonstrations showcase a substantial 5 mm range with a remarkable sensitivity of 1.148 GHz/mm, achieved using a basic single-mode fiber-based …

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A Data-Driven Adaptive Control Approach For Enhancing The Dynamic Response Ff Vsgs In Varying Grid Conditions, Shah Fahad, Buxin She, Junjie Yin, Fangxing Li, Hantao Cui, Rui Bo Jan 2025

A Data-Driven Adaptive Control Approach For Enhancing The Dynamic Response Ff Vsgs In Varying Grid Conditions, Shah Fahad, Buxin She, Junjie Yin, Fangxing Li, Hantao Cui, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

Conventionally, a virtual synchronous generator (VSG) is designed for islanded mode (IM) operation to meet specific operational requirements such as the rate of change of frequency (RoCoF). However, the operation of VSG designed for IM may not meet the operational and control criteria in grid connected mode (GCM) when the grid conditions vary. In addition, conventional VSG control technology does not consider the influence of the presynchronization scheme when connected to a weak grid, which degrades the RoCoF in IM. To overcome the aforementioned challenges, the proposed study presents a twin-delayed deep deterministic policy gradient (TD3) algorithm to improve the …

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Growing The Abriendo Oportunidades® Ecosystem: Equipping Young Mentors With Skills And Resources To Expand Girl-Centered Programming In Belize, Population Council Jan 2025

Growing The Abriendo Oportunidades® Ecosystem: Equipping Young Mentors With Skills And Resources To Expand Girl-Centered Programming In Belize, Population Council

Adolescents and Young People

Building on the success of the Abriendo Oportunidades® (AO®) program in Guatemala, in 2014 Population Council Guatemala (PC-Guatemala) and Toledo Mayan Women’s Council established the Toledo Adolescent Girls program (TAG), a safe space initiative that equipped young Indigenous girls and female mentors with life skills. The project demonstrated that neighboring countries are interested in expanding the AO model, and that the Council can successfully support programmatic adaptation to meet the needs of other Indigenous communities in Mesoamerica. This was achieved by introducing age-segmented groups, prioritizing transportation funding for mentors and supervisors, and continuing to tailor to local …

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Growing The Abriendo Oportunidades® Ecosystem: Spotlight On Escuela De Oportunidades, Population Council Jan 2025

Growing The Abriendo Oportunidades® Ecosystem: Spotlight On Escuela De Oportunidades, Population Council

Adolescents and Young People

Developed in partnership with the Office of the Vice President in 2021, Escuela de Oportunidades is a national internship program that intentionally invests in young female Indigenous professionals to increase their visibility in governance structures. Through a combination of mentorship, training, and practical experience, Escuela de Oportunidades has successfully facilitated the entry of Indigenous Guatemalan women into government institutions, enhancing gender and ethnic inclusivity in public service. This brief is part of the Abriendo Oportunidades® Legacy Series, celebrating and highlighting 20 years of impactful program implementation.

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Growing The Abriendo Oportunidades® Ecosystem: Sowing Seeds Of Change Within Government Systems, Population Council Jan 2025

Growing The Abriendo Oportunidades® Ecosystem: Sowing Seeds Of Change Within Government Systems, Population Council

Adolescents and Young People

Population Council-Guatemala (PC-Guatemala) is supporting and shaping a movement led by young Indigenous leaders to expand inclusive education and civic participation opportunities. Through mechanisms such as professional internships, school re-integration programs, and other government collaborations, young Indigenous women are building the knowledge, skills, and relationships to lead community development efforts and inform inclusive national policies. This brief is part of the Abriendo Oportunidades® Legacy Series, celebrating and highlighting 20 years of impactful program implementation.

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Growing The Abriendo Oportunidades® Ecosystem: Spotlight On Mentor Networks, Population Council Jan 2025

Growing The Abriendo Oportunidades® Ecosystem: Spotlight On Mentor Networks, Population Council

Adolescents and Young People

The emergence of REDMI Aq’ab’al and Na’leb’ak ONG, two civil society networks of young Indigenous women, represents a monumental evolution of the Abriendo Oportunidades® (AO®) program. As AO® successfully supported young female Indigenous mentors to increase their autonomy, community visibility, and professional skills, the formation and growth of these independent networks now promotes a larger movement of sustainable, responsive, and community-led social progress. It also provides a new platform for mentors to be recognized and credited for their work, even after they have “graduated” from direct participation in AO®. This brief is part of …

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The Social Life Of The Abriendo Oportunidades® Program In Guatemala: Three Decades Of Enabling Community And Civic Spaces For Indigenous Girls And Women, Population Council Jan 2025

The Social Life Of The Abriendo Oportunidades® Program In Guatemala: Three Decades Of Enabling Community And Civic Spaces For Indigenous Girls And Women, Population Council

Adolescents and Young People

Since 2004, Abriendo Oportunidades® (Opening Opportunities, AO) has emerged as a gender transformative social program to support Indigenous girls and young women in Guatemala’s post-war context. Following an evidence-based, community-anchored approach, AO began as a program and has evolved into a social movement. AO has continuously demonstrated its impact in reducing girls’ exposure to gender-based violence and pioneered alternative education through utilizing mentors as tutors. Over time, AO has successfully reached more than 25,000 Indigenous girls and adolescents across 500+ rural Guatemala communities and built a pathway of professional opportunities for the young women who lead the program. AO …

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Girls First Fund: External Evaluation—Endline Evaluation Report, Brian Medina Carranza, Neelanjana Pandey, Angel Del Valle, Fatima Zahra Jan 2025

Girls First Fund: External Evaluation—Endline Evaluation Report, Brian Medina Carranza, Neelanjana Pandey, Angel Del Valle, Fatima Zahra

Adolescents and Young People

The Population Council is leading an evaluation of programs funded by the Girls First Fund (GFF) in the Dominican Republic (DR), India, and Niger. These three countries were chosen to maximize geographic, social, cultural, and economic diversity across contexts, but common to all three is the continued persistence of child marriage and the presence of collective efforts to eliminate it. The broader goal of this evaluation is to: 1) demonstrate proof of concept for the impact of  GFF-supported programs; 2) examine key outcomes of interest to the GFF and the community-based organizations that it funds, including education, child marriage, and …

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Personalized Persuasion In The Digital Age: A Data-Driven Approach To Effective Communication, Annye Braca Jan 2025

Personalized Persuasion In The Digital Age: A Data-Driven Approach To Effective Communication, Annye Braca

Doctoral

This thesis investigates the potential of Machine Learning (ML) to personalize persuasive marketing messages. It explores the identification of individuals receptive to specific persuasion techniques based on their psychometric profiles. By developing ML models that incorporate these profiles, the thesis aims to predict the impact of tailored messages and improve the effectiveness of marketing communication.

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Development Of Holographic Optical Elements For Application In Wound Healing Monitoring, Pamela Stoeva Jan 2025

Development Of Holographic Optical Elements For Application In Wound Healing Monitoring, Pamela Stoeva

Doctoral

Growing global healthcare challenges, including the increasing prevalence of chronic wounds, necessitate the development of cost-effective, reusable, and readily accessible sensors for real-time wound monitoring. Such devices could extend basic healthcare to remote areas and support long-term space missions by facilitating on-the-spot wound assessment. Sensors that utilise Holographic Optical Elements (HOEs) are promising candidates due to their diverse sensing capabilities, advantageous physical properties (e.g., lightweight and flexibility), and suitability for mass manufacturing. The fundamental biochemical processes associated with wound healing are typically related to parameters such as oxygen levels, pH, temperature, and lactate concentration. Realtime quantification of these parameters enables …

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Highly Sensitive Diffractive Optical Structures For Detection Of Volatile Organic Compounds, Faolan Radford Mcgovern Jan 2025

Highly Sensitive Diffractive Optical Structures For Detection Of Volatile Organic Compounds, Faolan Radford Mcgovern

Doctoral

From aerospace to agriculture, sensors play a fundamental role in many aspects of modern life. Sensors form an integral part of the complex systems and devices required for the continued functioning and development of services and industries across society. The use of sensors is paramount in areas affecting human health, one such area being the monitoring of indoor air quality, in particular the detection of volatile organic compounds (VOCs). Human contact with VOCs has been associated with many health complications, including skin and eye irritation, cardiovascular damage, and cancers. Optical, electrical, gravimetric, and chemical sensors have been developed for VOC …

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Plasmonic Down-Shifting Layers For Cylindrical Solar Concentrators, Kenneth Coldrick Jan 2025

Plasmonic Down-Shifting Layers For Cylindrical Solar Concentrators, Kenneth Coldrick

Doctoral

The efficiency of photovoltaics (PVs) and photo-thermal (PT) systems is hindered by spectral mismatches and low thermal conductivity. A promising solution to address these issues can be the use of luminescent down-shifting (LDS) layers. This involves the incorporation of luminophores into solid or liquid layers that will act as spectral beam splitters (SBSs). In solid polymers, they form luminescent solar concentrators (LSCs), while in liquids, they act as working fluids and SBS for hybrid photovoltaic-photothermal (PVT) systems. This thesis will examine the energy conversion in both solid and liquid configurations through experimental, simulation, and economic analyses. An open-source model that …

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Capacity Building In The Irish Brewing And Distilling Sector For Raw Materials Utilisation, By-Products Management, And Environmental Impact Assessment, Ekene C. Umego Jan 2025

Capacity Building In The Irish Brewing And Distilling Sector For Raw Materials Utilisation, By-Products Management, And Environmental Impact Assessment, Ekene C. Umego

Doctoral

The Irish brewing and distilling sector has shown a consistent increase in number, production output, sales, and export value in the last decade. This has implications for raw materials requirements, assessment, and by-products management for the sustainability of the sector. As a result, the main aim of this research study was to evaluate the status of raw materials use and assessment within the Irish brewing and distilling sector, explore by-products management options and valorisation initiatives, and analyse the environmental impact of Irish whiskey production. The first approach was a survey study to collect data on major raw material inputs use …

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Celebrating 25 Years Of Collaboration: A Bibliography Of Afit-Afrl’S Top 50 Most-Cited Works, Wheeler Hall, Michelle Burwinkel Jan 2025

Celebrating 25 Years Of Collaboration: A Bibliography Of Afit-Afrl’S Top 50 Most-Cited Works, Wheeler Hall, Michelle Burwinkel

AFIT Library Knowledge Base

This bibliography compiles the 50 most-cited collaborative publications between the Air Force Institute of Technology (AFIT) and the Air Force Research Laboratory (AFRL) from 2000 to early 2025, showcasing their interdisciplinary impact across advanced science and engineering. Spanning materials science, remote sensing, terahertz spectroscopy, nanomaterials, aerospace, fatigue mechanics, biomedical applications, communication systems, optics, machine learning, and hypersonic engineering, the works highlight innovative methodologies and transformative applications. This collection underscores AFIT-AFRL’s contributions to cutting-edge research, offering valuable insights for researchers, engineers, and stakeholders in defense and technology development.

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Afit Librarian Newsletter : Check It Out (First Quarter 2025), D'Azzo Research Library, Air Force Institute Of Technology Jan 2025

Afit Librarian Newsletter : Check It Out (First Quarter 2025), D'Azzo Research Library, Air Force Institute Of Technology

AFIT Library Knowledge Base

Welcome to the first edition of our quarterly newsletter! We are excited to share with you the latest updates from our library.

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