Digital Commons Network^™

Improved Optimal Tracking Of Uncertain Nonlinear Discrete-Time Systems Using Experience Replay, Maxwell Geiger, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper addresses the infinite horizon optimal tracking control problem for partially uncertain control-affine nonlinear discrete-time (DT) systems, where the control input dynamics are known. Multi-layer critic and actor neural networks (MNNs) are utilized for online estimation of the infinite horizon value function and optimal control input. The NN weights are tuned online using a direct temporal difference error (TDE)-driven learning approach, which modifies the singular values of the gradient with respect to the NN weights to accelerate their convergence. The critic NN uses a novel experience replay technique to improve sample efficiency without introducing biased TDEs and guarantee the …

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 …

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 …

High-Frequency Accurate Dual-Side Equivalent Circuit Model For Transformers, Reza Vahdani, Junyong Park, Manish Kizhakkeveettil Mathew, Zhekun Peng, Chiuk Song, Hyucksu Kweon, Jiang Lijun, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

This study delves into the modeling of a transformer in the frequency range of 100 KHz to 30 MHZ. The coupling coefficient was considered as a function of leakage and self-inductance and incorporated in the optimization process of transformer modeling in the proposed method. The equivalent circuit focused on the critical aspects of leakage inductance, parasitic capacitance, and winding effects. At first, the winding effect of an air-core inductor over wide frequency range with both single-layer and double-layer windings was shown. Then an equivalent circuit was proposed to model a transformer over this frequency range. The comparison between the measured …

Designing For Relational Ethics In Online And Blended Learning: Levinas, Buber, And Teaching Interfaith Ethics, Michael Hubbard Mackay, Jason K. Mcdonald, Andrew C. Reed

Faculty Publications

Online and blended learning (OBL) overemphasize the process of creating artifacts, producing strategies, or otherwise utilizing a “making” orientation in education. As an alternative to this making-orientation, we offer a model for relational course design founded in the philosophies of Emmanuel Levinas and Martin Buber. We examine an OBL course design focused on interfaith leadership and ethics that lends itself to the need for relational pedagogy. The focus on asymmetrical and symmetrical relationships that separate Levinas and Buber’s philosophies enable rich ways of designing relational pedagogies and for resisting the making orientation. By focusing on human relationships, we demonstrate design …

Modeling Of Slot-Backed Microstrip Line For Emi Applications, Jongsuk Hyun, Wenchang Huang, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Radiated emissions from the noise-generating components in modern electronic devices are a significant concern for both electromagnetic interference and RF interference. Shielding cans are commonly used to suppress emissions from noise sources, but accurate shielding effectiveness evaluation requires a clean, well-defined radiation source that can reliably mimic real emissions for repeatable measurements. Slot-backed microstrip antennas provide a practical alternative to loop antennas, offering zero height, low parasitic radiation, and seamless printed circuit board integration. This article proposes an analytical model for estimating the magnetic dipole moment of slot-backed microstrip structures. The model captures both the discontinuity effects and radiated characteristics …

Ethics Vs.. Regulation: Converging Frameworks For Trustworthy Human-Centered Ai In Biomedical Research, Tayo Obafemi-Ajayi, Tiffani J. Bright, Emily F. Wong, Donald Wunsch, Joan Peckham, Jason H. Moore

Electrical and Computer Engineering Faculty Research & Creative Works

The accelerating impact of AI in biomedical research is driving significant advances in precision medicine. As these systems increasingly shape health outcomes, the imperative to develop trustworthy, reliable, and ethically grounded AI becomes more pressing, particularly in addressing concerns related to data integrity, patient safety, and equitable outcomes. While the potential of AI to transform biomedical research is clear, its responsible integration depends on more than technological capability. Ensuring that these systems are aligned with societal values requires a dual commitment: the operationalization of ethical principles throughout the AI life cycle and the establishment of robust regulatory mechanisms. Ethics provides …

Nonperturbative Aspects Of The Electromagnetic Pion Form Factor At High Energies, K. Quirion, C. Fernandez-Ramirez, V. Mathieu, G. Montaña, R. J. Perry, A. Pilloni, A. Rodas, V. Shastry, W. A. Smith, A. P. Szczepaniak, D. Winney

Physics Faculty Publications

The structure of hadronic form factors at high energies and their deviations from perturbative quantum chromodynamics provide insight on nonperturbative dynamics. Using an approach that is consistent with dispersion relations, we construct a model that simultaneously accounts for the pion wave function, gluonic exchanges, and quark Reggeization. In particular, we find that quark Reggeization can be investigated at high energies by studying scaling violation of the form factor.

Background-Field Method And Qcd Factorization, Ian Balitsky

Physics Faculty Publications

One method for deriving a factorization for QCD processes is to use successive integration over fields in the functional integral. In this approach, we separate the fields into two categories: dynamical fields with momenta above a relevant cutoff, and background fields with momenta below the cutoff. The dynamical fields are then integrated out in the background of the low-momentum background fields. This strategy works well at tree level, allowing us to quickly derive QCD factorization formulas at leading order. However, to extend the approach to higher loops, it is necessary to rigorously define the functional integral over dynamical fields in …

Flavor Dependence Of Charged Pion Fragmentation Functions, H. Bhatt, P. Bosted, S. Jia, W. Armstrong, D. Dutta, R. Ent, D. Gaskell, E. Kinney, H. Mkrtchyan, S. Ali, R. Ambrose, D. Androić, C. Ayerbe Gayoso, A. Bandari, V. Berdnikov, D. Bhetuwal, D. Biswas, M. Boer, E. Brash, A. Camsonne, M. Cardona, J. P. Chen, J. Chen, M. Chen, E. M. Christy, S. Danagoulian, M. Diefenthaler, S. Covrig, B. Duran, M. Elaasar, C. Elliot, H. Fenker, E. Fuchey, J. O. Hansen, F. Hauenstein, T. Horn, G. M. Huber, M. K. Jones, M. L. Kabir, A. Karki, B. Karki, S. J. D. Kay, C. Keppel, V. Kumar, N. Lashley-Colthirst, W. B. Li, D. Mack, S. Malace, P. Markowitz, M. Mccaughan, E. Mcclellan, D. Meekins, R. Michaels, A. Mkrtchyan, G. Niculescu, I. Niculescu, B. Pandey, S. Park, E. Pooser, B. Sawatzky, G. R. Smith, H. Szumila-Vance, A. S. Tadepalli, V. Tadevosyan, R. Trotta, H. Voskanyan, S. A. Wood, Z. Ye, C. Yero, X. Zheng

Physics Faculty Publications

We have measured the flavor dependence of multiplicities for π⁺ and π⁻ production in semi-inclusive deep-inelastic scattering (SIDIS) on proton and deuteron to explore a possible charge symmetry violation in fragmentation functions. The experiment used an electron beam with energies of 10.2 and 10.6 GeV at Jefferson Lab and the Hall-C spectrometers. The electron kinematics spanned the range 0.3 < x < 0.6, 2 < Q² < 5.5 GeV², and 2.2 < W < 3.2 GeV. The pion fractional momentum range was 0.3 < z < 0.7, and the transverse momentum range was 0 < p_T < 0.25 GeV/c. Assuming factorization and allowing for isospin breaking, the results can be described by two “favored” and two “unfavored” effective low p_T fragmentation functions that are flavor-dependent. We find each pair converges to a common flavor-independent fragmentation function at the highest W, where factorization is most applicable.

Avenues For A Number Density Interpretation Of Dihadron Fragmentation Functions, T. Rogers, A. Courtoy

Physics Faculty Publications

In this letter, we reassess the underlying physics of the number sum rule for dihadron fragmentation functions. We will argue that, currently, there are no settled constraints on what constitutes a valid number density interpretation for multihadron fragmentation functions. Imposing overly restrictive criteria might lead to misinterpretating the data. Most importantly, and on the basis of phenomenological analyses, the slightly varying definitions used in previous work are not excluded from possessing legitimate number density interpretations (up to the usual issues with ultraviolet divergences and renormalization), so long as they are paired with appropriate factorization theorems. We advocate for further theoretical …

Sensitivity Analysis Of The 197 Mhz Prototype Crab Cavity For Eic, Subashini De Silva, Jean R. Delayen, B. Xiao, E. Drachuk, I. H. Senevirathne, A. Castilla, N. Huque, Z. Li

Physics Faculty Publications

The Electron-Ion Collider at BNL requires several crabbing systems that will be operating at 197 MHz and 394 MHz to compensate for the loss of luminosity due to the large crossing angle of the colliding beams. Two 197 MHz crab cavity cryomodules containing two cavities each will be installed in the Hadron Storage Ring (HSR) at the IP6 interaction region. Due to its large size compared to previously developed crabbing cavities, the 197 MHz crabbing cavity system was identified as one of the critical rf systems in the EIC. Therefore, a cavity has been designed including the ancillaries, and is …

First Measurement Of Near-Threshold And Subthreshold J/Ѱ Photoproduction Off Nuclei, J. R. Pybus, L. Ehinger, T. Kolar, B. Devkota, P. Sharp, B. Yu, M. M. Dalton, D. Dutta, H. Gao, O. Hen, E. Piasetzky, S. N. Santiesteban, A. Schmidt, A. Somov, H. Szumila-Vance, S. Adhikari, A. Asaturyan, A. Austregesilo, C. Ayerbe Gayoso, J. Barlow, V. V. Berdnikov, H. D. Bhatt, D. Bhetuwal, T. Black, W. J. Briscoe, G. Chung, P. L. Cole, A. Deur, R. Dotel, H. Egiyan, P. Eugenio, C. Fanelli, L. Gan, A. Gasparian, J. Guo, K. Hernandez, D. W. Higinbotham, P. Hurck, I. Jaegle, R. T. Jones, V. Kakoyan, A. Karki, H. Li, W. B. Li, G. R. Linera, V. Lyubovitskij, H. Marukyan, M. D. Mccaughan, M. Mccracken, K. Mizutani, D. Nguyen, S. Oresic, A. I. Ostrovidov, Z. Papandreou, C. Paudel, K. Peters, J. Ritman, A. Schick, J. Schwiening, A. Smith, S. Somov, I. Strakovsky, K. Suresh, V. V. Tarasov, S. Taylor, T. Xiao, Z. Zhang, X. Zhou

Physics Faculty Publications

We report on the first measurement of J/ψ photoproduction from nuclei in the photon energy range of 7 to 10.8 GeV, extending above and below the photoproduction threshold in the free proton of ∼8.2 GeV. The experiment used a tagged photon beam incident on deuterium, helium, and carbon, and the GlueX detector at Jefferson Lab to measure the semi-inclusive A(γ,e⁺e^-p) reaction with a dilepton invariant mass M(e⁺e^-)∼m_J/ψ=3.1 GeV. The incoherent J/ψ photoproduction cross sections in the measured nuclei are extracted as a function of the incident photon energy, momentum transfer, …

Emc Effect Of Tritium And Helium-3 From The Jlab Marathon Experiment, D. Abrams, H. Albataineh, B. S. Aljawmeh, S. Alsalmi, D. Androic, K. Aniol, W. Armstrong, J. Arrington, H. Atac, T. Averett, C. Ayerbe Gayoso, X. Bai, J. Bane, S. Barcus, A. Beck, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, D. Blyth, W. Boeglin, D. Bulumulla, J. Butler, A. Camsonne, M. Carmignotto, J. Castellanos, J. -P. Chen, I. C. Cloët, E. O. Cohen, S. Covrig, K. Craycraft, R. Cruz-Torres, B. Dongwi, B. Duran, D. Dutta, N. Fomin, E. Fuchey, C. Gal, T. N. Gautam, S. Gilad, K. Gnanvo, T. Gogami, J. Gomez, C. Gu, A. Habarakada, T. Hague, J. -O. Hansen, M. Hattawy, F. Hauenstein, D. W. Higinbotham, R. J. Holt, E. W. Hughes, C. Hyde, H. Ibrahim, S. Jian, S. Joosten, A. Karki, B. Karki, A. T. Katramatou, C. Keith, C. Keppel, M. Khachatryan, A. Khanal, A. Kievsky, D. King, P. M. King, I. Korover, S. A. Kulagin, K. S. Kumar, T. Kutz, N. Lashley-Colthirst, S. Li, W. Li, H. Liu, S. Liuti, N. Liyanage, P. Markowitz, R. E. Mcclellan, D. Meekins, S. Mey-Tal Beck, Z. -E. Meziani, R. Michaels, M. Mihovilovic, V. Nelyubin, D. Nguyen, Nuruzzaman, M. Nycz, R. Obrecht, M. Olson, V. F. Owen, E. Pace, B. Pandey, V. Pandey, M. Paolone, A. Papadopoulou, S. Park, S. Paul, G. G. Petratos, R. Petti, E. Piasetzky, R. Pomatsalyuk, S. Premathilake, A. J. R. Puckett, V. Punjabi, R. D. Ransome, M. N. H. Rashad, P. E. Reimer, S. Riordan, J. Roche, G. Salmè, N. Santiesteban, B. Sawatzky, A. Schmidt, B. Schmookler, S. Scopetta, J. Segal, E. P. Segarra, A. Shahinyan, S. Širca, N. Sparveris, T. Su, R. Suleiman, H. Szumila-Vance, A. S. Tadepalli, L. Tang, W. Tireman, F. Tortorici, G. M. Urciuoli, B. Wojtsekhowski, S. Wood, Z. H. Ye, J. Zhang

Physics Faculty Publications

Measurements of the EMC effect in the tritium and helium-3 mirror nuclei are reported. The data were obtained by the MARATHON Jefferson Lab experiment, which performed deep inelastic electron scattering from deuterium and the three-body nuclei, using a cryogenic gas target system and the high resolution spectrometers of the Hall A Facility of the Lab. The data cover the Bjorken x range from 0.20 to 0.83, corresponding to a squared four-momentum transfer Q² range from 2.7 to 11.9  (GeV/c)², and to an invariant mass W of the final hadronic state greater than 1.84  GeV/c². The tritium EMC effect measurement is …

New Measurements Of The Deuteron-To-Proton F₂ Structure-Function Ratio, D. Biswas, F. A. Gonzalez, W. Henry, A. Karki, C. Morean, A. Nadeeshani, A. Sun, Z. Ahmed, S. Alsalmi, W. Armstrong, A. Asaturyan, C. Ayerbe Gayoso, V. Berdnikov, H. Bhatt, D. Bhetuwal, P. Bosted, E. Brash, M. H. S. Bukhari, J. P. Chen, M. Chen, M. E. Christy, S. Covrig Dusa, K. Craycraft, S. Danagoulian, D. Day, M. Diefenthaler, M. Dlamini, J. Dunne, B. Duran, D. Dutta, R. Ent, H. Fenker, N. Fomin, E. Fuchey, D. Gaskell, T. N. Gautam, J. O. Hansen, F. Hauenstein, A. V. Hernandez, T. Horn, G. M. Huber, M. K. Jones, S. Joosten, M. L. Kabir, C. Keppel, A. Khanal, P. M. King, E. Kinney, M. Kohl, M. Lashley-Colthirst, S. Li, W. B. Li, A. H. Liyanage, D. Mack, S. Malace, P. Markowitz, J. Matter, D. Meekins, R. Michaels, A. Mkrtchyan, Z. Moore, S. J. Nazeer, S. Nanda, G. Niculescu, I. Niculescu, D. Nguyen, B. Pandey Nuruzzaman, S. Park, E. Pooser, A. J. R. Puckett, M. Rehfuss, J. Reinhold, B. Sawatzky, G. R. Smith, H. Szumila-Vance, A. S. Tadepalli, V. Tadevosyan, R. Trotta, S. A. Wood, C. Yero, J. Zhang

Physics Faculty Publications

Nucleon structure functions, as measured in lepton-nucleon scattering, have historically provided a critical observable in the study of partonic dynamics within the nucleon. However, at very large parton momenta, it is both experimentally and theoretically challenging to extract parton distributions due to the probable onset of nonperturbative contributions and the unavailability of high-precision data at critical kinematics. Extraction of the neutron structure and the d quark distribution have been further challenging because of the necessity of applying nuclear corrections when utilizing scattering data from a deuteron target to extract the free neutron structure. However, a program of experiments has been …

Multidimensional Measurements Of Beam Single-Spin Asymmetries In Semi-Inclusive Deep-Inelastic Charged-Kaon Electroproduction Off Protons In The Valence Region, Clas Collaboration, A. Kripko, S. Diehl, K. Joo, P. Achenbach, J. S. Alvarado, M. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, L. Bashkanov, F. Benmokhtar, A. Bianconi, A. S. Biselli, M. Bondi, F. Bossù, S. Boiarinov, K. -T. Brinkmann, W. J. Briscoe, W. K. Brooks, T. Cao, R. Capobianco, D. S. Carman, J. C. Carvajal, A. Celentano, P. Chatagnon, G. Ciullo, P. L. Cole, M. Contalbrigo, V. Crede, A. D'Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, C. Dilks, C. Djalali, R. Dupre, H. Egiyan, A. El Alaoui, L. El Fassi, L. Elouadrhiri, S. Fegan, I. P. Fernando, A. Filippi, G. Gavalian, G. P. Gilfoyle, D. I. Glazier, R. W. Gothe, Y. Gotra, K. Hafidi, H. Hakobyan, M. Hattawy, F. Hauenstein, T. B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, H. Jiang, H. S. Jo, T. Kageya, A. Kim, W. Kim, V. Klimenko, V. Kubarovsky, S. E. Kuhn, L. Lanza, P. Lenisa, X. Li, Z. Lu, I. J. D. Macgregor, D. Marchand, D. Martiryan, V. Mascagna, D. Matamoros, M. Maynes, B. Mckinnon, R. G. Milner, T. Mineeva, M. Mirazita, V. Mokeev, C. Munoz Camacho, P. Nadel-Turonski, T. Nagorna, K. Neupane, D. Nguyen, S. Niccolai, G. Niculescu, M. Osipenko, M. Ouillon, P. Pandey, L. L. Pappalardo, R. Paremuzyan, E. Pasyuk, S. J. Paul, N. Pilleux, S. Polcher Rafael, J. Poudel, J. W. Price, Y. Prok, T. Reed, M. Ripani, J. Ritman, C. D. Roberts, P. Rossi, A. A. Rusova, S. Schadmand, A. Schmidt, Y. G. Sharabian, E. V. Shirokov, S. Shrestha, U. Shrestha, D. Sokhan, N. Sparveris, M. Spreafico, I. I. Strakovsky, S. Strauch, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, T. Vittorini, H. Voskanyan, A. Vossen, E. Voutier, Y. Wang, D. P. Watts, U. Weerasinghe, X. Wei, M. H. Wood, L. Xu, S. -S. Xu, N. Zachariou, V. Ziegler, M. Zurek

Physics Faculty Publications

Measurements of beam single-spin asymmetries in semi-inclusive deep-inelastic electron scattering (SIDIS) with positively charged kaons off protons have been performed with 10.6 and 10.2 GeV incident electron beams using the CLAS12 spectrometer at Jefferson Lab. We report an analysis of the electroproduction of positively charged kaons over a large kinematic range of fractional energy, Bjorken x, transverse momentum, and photon virtualities Q² ranging from 1 GeV² up to 6 GeV². This is the first published multidimensionally binned CLAS12 measurement of a kaon SIDIS single-spin asymmetry in the valence quark regime. The data provide constraints on the structure function ratio …

Surface Currents In The Mid-Atlantic Bight: The Role Of The Gulf Stream Versus Wind, Tal Ezer

CCPO Publications

Surface currents of the Mid-Atlantic Bight (MAB) were studied using high frequency radar (HFR) observations at 6 km resolution during a five-year period (2020-2024). The study's focus on the role of the Gulf Stream (GS) contrasts with most past studies that focused on the seasonal wind-driven currents. Empirical Orthogonal Function (EOF) analyses of the daily HFR currents were conducted with and without the GS, revealing modes of current variability linked to the seasonal wind pattern and storms versus modes linked to GS variability. The remote impact of the GS on coastal currents is complex, with different impacts seen on different …

Multi-Model Estimate Of Antarctic Ice-Shelf Basal Mass Budget And Ocean Drivers, Benjamin K. Galton-Fenzi, Richard Porter-Smith, Sue Cook, Eva Cougnon, David E. Gwyther, Wilma G. C. Huneke, Madelaine G. Rosevear, Xylar Asay-Davis, Fabio Boeira Dias, Michael S. Dinniman, David Holland, Kazuya Kusahara, Kaitlin A. Naughten, Keith W. Nicholls, Charles Pelletier, Ole Richter, Hélène Seroussi, Ralph Timmerman

CCPO Publications

Societal adaptation to rising sea levels requires robust projections of the Antarctic Ice Sheet's retreat, particularly due to ocean-driven basal melting of its fringing ice shelves. Recent advances in ocean models that simulate ice-shelf melting offer an opportunity to reduce uncertainties in ice–ocean interactions. Here, we compare several community-contributed, circum-Antarctic ocean simulations to highlight inter-model differences, evaluate agreement with satellite-derived melt rates, and examine underlying physical processes. All but one simulation use a melting formulation depending on both thermal driving (T^⋆) and friction velocity (u^⋆), which together represent the thermal and ocean current forcings at the …

Developing Human-Centric Informational Security, Jonathon W. Penney

Articles & Book Chapters

Disinformation and information manipulation are widely seen as an urgent threat to democracy, but less often as a cybersecurity threat. Historically, disinformation has rarely been included in lists of recognized threats in cybersecurity manuals and appendices of global standards organizations and only recently has disinformation been approached as a cybersecurity threat, with only a handful of works offering a more focused and systematic discussion on this point. This chapter aims to help fill this void by arguing not only that disinformation and information manipulation is a cybersecurity threat, but that the present predominant cybersecurity paradigm is largely inadequate to address …

Residual Effect Of Silicate Agromineral Application On Soil Acidity, Mineral Availability, And Soybean Anatomy, Mariana De Carvalho Ribeiro, Antonio Ganga, Isabella Silva Cattanio, Aline Redondo Martins, Rodrigo Silva Alves, Luís Gustavo Frediani Lessa, Hamilton Seron Pereira, Fernando Shintate Galindo, Marcelo Carvalho Minhoto Teixeira Filho, Cassio Hamilton Abreu-Junior, Gian Franco Capra, Arun Dilipkumar Jani, Thiago Assis Rodrigues Nogueira

Biology, Agriculture and Chemistry Faculty Publications and Presentations

Silicate agrominerals (SA) may be sustainable soil amendments that can minimize dependence on conventional fertilizers (CF). We evaluated the residual effects of SA application as a source of Si and as a soil remineralizer, using soils with contrasting chemical-physical features cultivated with soybean. The experiment was conducted under greenhouse conditions and treatments were arranged in a 5 × 2 + 2 factorial scheme: five rates of SA, two soils in addition to CF. The soil was incubated before cultivation, followed by the sequential sowing of corn and soybean. At the R4 phenological stage, when the pods were fully developed, soybean …

Nebraska Test #2301: Claas Xerion 12.650, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Test #2300: Claas Xerion 12.590 Terra Trac, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Test #2297: John Deere 9rx 770, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Test #2298: John Deere 9rx 830, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Exploring The Effect Of Item Parceling Strategies And Number Of Items Per Parcel On Measurement Invariance Testing In Confirmatory Factor Analysis, Chunhua Cao, Xinya Liang

Psychological Science Faculty Publications and Presentations

Item parceling is common in structural equation modeling used in psychology, especially when the research interest is in the structural relationship between latent factors, but research on its performance in measurement invariance testing is scarce. This study examined the sensitivity of fit measures (LRT, RMSEA, CFI, AIC, BIC, and SaBIC) to measurement noninvariance with different numbers of items per parcel and parceling strategies using a simulation study. The design factors included the location of measurement noninvariance, the magnitude of measurement noninvariance, the proportion of items with measurement noninvariance, sample size, number of items per parcel, and parceling strategies. Results suggested …

Severe Aggression Among Zoo-Housed Coconut (Trichoglossus Haematodus) And Rainbow (Trichoglossus Moluccanus) Lorikeets: Wellbeing Considerations For Free-Flight Aviaries, Emily Simkins

UNF Graduate Theses and Dissertations

As conservation and education institutions, modern zoos balance the needs of animals with the interests of visitors through several strategies which can increase animal wellbeing and improve visitor experience. Environmental enrichment is frequently employed to increase the suitability of anthropogenic environments for zoo-housed animals, such as through walkthrough habitats and free-flight aviaries. While habitats such as these are important for visitor experience and can be enriching to animals, there are also wellbeing considerations for these spaces. Walkthrough habitats can be a potential source of fear and stress for animals, as shown by increased frequencies of vigilance, undesirable behavior, and aggression. …

Fourier Transformation Of Non-Periodic Functions And Its Application In Computed Tomography, Sabrina Hossain

UNF Graduate Theses and Dissertations

Fourier analysis plays an important role in signal processing and imaging applications,

with computed tomography (CT) being a prominent example. CT imaging relies on recon-

structing cross-sectional images of objects from multiple projections, a process deeply rooted

in the mathematical framework of the Fourier series and its extensions. This thesis explores

the mathematical principle behind CT, demonstrating how periodic and non-periodic func-

tions can be decomposed into sinusoidal components to facilitate image reconstruction. We

begin by reviewing the Fourier series and its ability to represent periodic signals, and then

extend this concept to non-periodic functions through Fourier transforms. The connection …

Leucine Catabolism Is Associated With Longevity In Female Eastern Lubber Grasshoppers, Kerri R. Conklin

UNF Graduate Theses and Dissertations

Background & Aims: Dietary isoleucine restriction can improve metabolic health and increase lifespan. It has been hypothesized that shifts in branched-chain amino acid catabolism drives this longevity effect. Impaired branched-chain amino acid catabolism is linked to several age-related diseases. We investigated whether dietary isoleucine restriction increases leucine catabolism and associates with longevity and full reproduction.

Methods: In two experiments, adult female Eastern Lubber grasshoppers (Romalea microptera) were assigned to either a high-quality diet (Balanced ile), or diets with varying isoleucine content (Moderate ile-R and Severe ile-R). In Experiment 1, we used a low-energy (Low Lettuce) group as a positive …

Investigating The Roles Of Intrinsic Point Defects And Transition Metal Doping In Monolayer And Bulk Tis2, Patrick J. Keeney

UNF Graduate Theses and Dissertations

Within this thesis, the magnetic and electronic properties of various 1T-TiS₂ systems are thoroughly examined using density functional theory (DFT) and scanning tunneling microscopy (STM). Formation energies and electronic implications of intrinsic point defects in bulk TiS₂ and monolayer TiS₂ are analyzed by approximating a computational monolayer of TiS₂ as the surface layer of a bulk sample. This approximation is validated given that intralayer covalent bonding dominates interlayer van der Waals interactions. We conclude that the most energetically favorable intrinsic defects are Ti atoms settling above the outermost S plane and S vacancies. In addition, the …

Rodcast Interaction: A Novel Technique For Dense Virtual Reality Environments, Nevzat U. Demirseren

UNF Graduate Theses and Dissertations

Virtual Reality (VR) technologies continue to grow in popularity and application versatility, yet effective interaction within complex dense environments remains as a critical challenge. In particular, users with low level of VR experience often face decreased accuracy and dissatisfaction selecting occluded objects. A variety of interaction techniques to select and manipulate objects exist, but there is a research gap in understanding what kinds of techniques support users in dense environments. This study evaluates the user performance and preference in such environments. Three interaction techniques are examined in this study: Go-Go Hand, Flower Cone, and a proposed technique called RodCast Interaction. …