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Articles 1081 - 1110 of 302419

Full-Text Articles in Physical Sciences and Mathematics

Applying "Farmer-First Research" In New Zealand, A F. Mcrae, F M. Anderson, R Brazendale Aug 2024

Applying "Farmer-First Research" In New Zealand, A F. Mcrae, F M. Anderson, R Brazendale

IGC Proceedings (1993-2023)

The disciplinary orientation and other characteristics of traditional agricultural research may result in farmers' research needs not being central to the research proces·s. A Farmer-First Research programme (FFR) has been initiated to complement the traditional research approach. This programme involves collaboration with hill country sheep and beef farmers chosen at random from across the fuff range of farmer circumstances. It sets out to diagnose and describe where scope· exists to Improve farmers' circumstances, and lo design and test relevant innovations on-farm. In addition to seeking to improve research output for far1ners, the· programme has the objective of evaluating the Farmer-First …


Technology Transfer Strategies For Products Of Environmental Research And Development Projects, N D. Macleod, J A. Taylor, P.G H. Van Beek, P N. Vance Aug 2024

Technology Transfer Strategies For Products Of Environmental Research And Development Projects, N D. Macleod, J A. Taylor, P.G H. Van Beek, P N. Vance

IGC Proceedings (1993-2023)

Potentially high net benefits from Research and Development on sustainable grazing systems will not be captured unless the outcomes are adopted. Adoption is a complex process, often requiring integration with other technologies, and specialised extension packages. Technology transfer strategies based on experiences with relatively simple innovations are unsuited to more complex environmental innovations, A 6-stage interactive process involving researchers, extension specialists and potential end-users is suggested.


Development Of Environmental And Agricultural Professionalism, Robert F. Barnes, Thomas J. Hall Aug 2024

Development Of Environmental And Agricultural Professionalism, Robert F. Barnes, Thomas J. Hall

IGC Proceedings (1993-2023)

The American Society of Agronomy {ASA) is' co-ordinating the development of a \ioluritary certification programme for the men and women who··make nutrient management strategies for farmers .• This paper examines the need, "history and obstacles in developing a crop advisor certification programme. Past arid proposed state and national legislative initiatives have indicated to some industry leaders that certification programmes' will be needed ·to operate in the coming regulat6ry environment. Other members· of industry· feel chat voluntary certification will bring on mandated programmes, The' differences in outlook, the diversity of the audience and the academic orientation of ASA ·have all created …


Grazier's Pattern Of Understanding Vegetation In The Semi-Arid Rangelands Of New South Wales, S.M M. Kersten, R L. Ison Aug 2024

Grazier's Pattern Of Understanding Vegetation In The Semi-Arid Rangelands Of New South Wales, S.M M. Kersten, R L. Ison

IGC Proceedings (1993-2023)

A matrix ranking (MR) technique was used by graziers in western New South Wales to rank rangeland plants according to preference. Graziers preferred a variety of plant species in their paddocks: "bushes" and "50f1 feed", perennials and annuals, winter-and summer­growing plants, on both stock-based and non-stock-based criteria, The criteria for evaluation were rarely independent of each other nor of different soil types on the grai:ier's property. Drought resistance was perceived as one of the more important criteria, followed by stock-based criteria such as "nutritious", "palatable" or "quick fattening" stock feed. The utility of MR for allowing graziers' knowledge to be …


Composition Of The Fractions Of Dry, Mature Subterranean Clover Digested In Vivo And In Vitro, L Klein, S K. Baker Aug 2024

Composition Of The Fractions Of Dry, Mature Subterranean Clover Digested In Vivo And In Vitro, L Klein, S K. Baker

IGC Proceedings (1993-2023)

A modified pepsin-cellulase procedure was used to improve the prediction of in vivo digestibility of dry, mature subterranean clovers (Trifolium subterraneum). Feed, faeces, and the residues from this /11 vitro procedure and the i11 vitro procedure of Tilley & Terry were analysed for protein, ash and fibre fractions lo determine the composition of the cell-wall functions that were digested. The extent of digestion of the cell-wall fractions differed between the two in vitro procedures, but the cell-wall fraction that was digested contained similar proportions of cellulose, hemicellulose, protein and lignin. The cellulose and protein contents of the cell-wall digested …


Effect Of Plant Leaf Age On The Production Of Tannins, Phenols, Proanthocyanidins And Flavanols In Eulalia Villosa, M M. Wolfson, E W. Du Toit, P Chesselet Aug 2024

Effect Of Plant Leaf Age On The Production Of Tannins, Phenols, Proanthocyanidins And Flavanols In Eulalia Villosa, M M. Wolfson, E W. Du Toit, P Chesselet

IGC Proceedings (1993-2023)

Histochemical and biochemical analyses have confirmed the presence of condensed tannins in a number of southern African tropical grasses. The ability to precipitate proteins, total phenols, condensed tannin and proanthocyanidin levels were significantly higher in mature leaves of Eulalia villosa than in young leaves. The ratio of condensed tannin to Jlavan 3,4-diols indicated that the young leaf material contained more monomeric unpolymerised flavan 3,4-diol units than mature leaves. The trend is repeated in the ratio 'of proanthocyanidin to flavan-4-ols, These low molecular weight proanthocyanidin precursors probably do not have the ability to precipitate proteins, The histochemical tests can be used …


Effect Of Inoculants And Absorbents Incorporated In Grass Silage On Silage Quality, Effluent Production And Animal Performance, Raymond Jones Aug 2024

Effect Of Inoculants And Absorbents Incorporated In Grass Silage On Silage Quality, Effluent Production And Animal Performance, Raymond Jones

IGC Proceedings (1993-2023)

Unwilled ryegrass crops (151 kg DM) were enslled in 70-t bunker silos. Crop analysis (g/kg/DM) was water-soluble carbohydrates 153, nitrogen 24.1 and predicted digestibility (DOMD) 0.67. Molassed sugar beet feed pellets were incorporated at a rate of 25 kg/t in the harvested crop with or without inoculant treatment ("Live Systems", MMB, UK), and compared with a control silage with no additive. Absorbent addition with or without inoculant significantly reduced silage pH and ammonia-N compared with the control. Inoculant treatment further increased lactic acid content. Silage effluent production was reduced by up to 33% by absorbent inclusion with effluent DM losses …


Near-Infrared Spectroscopy Analysis Of The Nutrient Content Of Dairy Pastures, R C. Kellaway, C Stimson, R J. Tassell Aug 2024

Near-Infrared Spectroscopy Analysis Of The Nutrient Content Of Dairy Pastures, R C. Kellaway, C Stimson, R J. Tassell

IGC Proceedings (1993-2023)

Pasture samples from temperate and tropical species were collected before and after grazing, at regular intervals, on 3 dairy farms in New South Wales over a period of 3 years. All samples (n=693) were analysed on a near-infrared (NIR) spectrophotometer with a scanning monochromator. Subsets of samples selected for calibration and validation, were analysed by wet chemistry methods for estimated metabolisable energy (MID), crude protein (CP), organic matter (OM), acid-detergent fibre (ADF), Ca, P, Mg, K, Na, S, Cu, Mn and Zn. These data were used lo develop NIR equations using partial least squares analyses. Standard errors of laboratory analysis …


Influence Of Oxygen Leakage Through Stretch Film On Quality Of Round Bale Silage, P Lingvall, C M. Pettersson, P Wilhelmsson Aug 2024

Influence Of Oxygen Leakage Through Stretch Film On Quality Of Round Bale Silage, P Lingvall, C M. Pettersson, P Wilhelmsson

IGC Proceedings (1993-2023)

The ensiling-process is based on anaerobic conditions. Therefore, it is important to get "air tight" parcels covering big-bale silage. Wrapping round bales wilh stretch film has improved silage quality, and reduced diy matter (OM) and energy losses. In this experiment we studied the influence of stretch film quality, film thickness, .storage temperature and storage place on fermentation, microbial growth/ and DM losses. Additionally, oxygen permeability of stretch film wrapped in 4 or 6 layers around artificial bales (metal) and DM losses was tested In a model. High storage temperature, low total film thickness and high film permeability to oxygen increased …


Container Migration: A Perfomance Evaluation Between Migrror And Pre-Copy, Xinwen Liang Aug 2024

Container Migration: A Perfomance Evaluation Between Migrror And Pre-Copy, Xinwen Liang

Electronic Thesis and Dissertation Repository

The concept of migration and checkpoint/restore has been a very important topic in research for many types of applications including any distributed systems/applications or single massive systems/applications; and low latency vehicular use cases, augmented reality(AR) and virtual reality(VR) applications. Migrating a service requires that the state of the service is preserved. This requires checkpointing the state and restoring it on a different server in multiple rounds to avoid a total loss of all data in case of a failure, fault or error. There are many different types of migration techniques utilized such as cold migration, pre-copy migration, post-copy migration.

Compared …


Single Charge Carrier Dynamics In A Single Polymer Chain, Ming Lei Aug 2024

Single Charge Carrier Dynamics In A Single Polymer Chain, Ming Lei

All Dissertations

Understanding how charge carrier move through conjugated polymers is crucial for optimizing the functionality and efficiency of various applications, from organic solar cells and light-emitting diodes (LEDs) to field-effect transistors. Previous studies have demonstrated that tracking the fluorescence centroid displacement provides a method to determine the position of single charge carriers in a conjugated polymer nanoparticle. This method allows the observation of charge carrier trajectories over time and allow researchers to obtain insights into the dynamic processes. In addition, a detailed map of the energy landscape can be constructed by analyzing the fluorescence spectrum. These techniques were previously applied to …


Offensive Content Detection In Online Social Platforms, Ebuka Okpala Aug 2024

Offensive Content Detection In Online Social Platforms, Ebuka Okpala

All Dissertations

Online social platforms enable users to connect with large, diverse audiences and the ability for a message or content to flow from one user to another user, user to followers, followers to user, and followers to followers. Of course, the advantages of this are apparent, and the dangers are also clearly obvious. The user-generated content could be abusive, offensive, or hateful to other users, possibly leading to adverse health effects or offline harm. As more of society's public discourse and interaction move online and these platforms grow and increase their reach, it is inherently important to protect the safety of …


Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner Aug 2024

Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner

All Dissertations

Polychlorinated biphenyls (PCBs) and trichloroethene (TCE) are ubiquitous contaminants and are recognized as persistent organic pollutants due to their extreme chemical stability. PCBs were manufactured by chlorinating biphenyls that created 209 congeners with various structures, of which 19 are chiral and can exist as a pair of stable atropisomers. PCBs have been known to cause developmental and neurological toxicity in humans and wildlife; they can act as endocrine disrupters, carcinogens, and teratogens. Sangamo Weston Inc. was an industrial plant located near Town Creek in Pickens Country, South Carolina, that manufactured capacitors and used Aroclors 1016 and 1254 as dialectic fluids …


Ensuring The Privacy Compliance Of Voice Personal Assistant Applications, Song Liao Aug 2024

Ensuring The Privacy Compliance Of Voice Personal Assistant Applications, Song Liao

All Dissertations

Voice Personal Assistants (VPA) such as Amazon Alexa and Google Assistant are quickly and seamlessly integrating into people’s daily lives. Meanwhile, the increased reliance on VPA services raises privacy concerns, such as the leakage of private conversations and sensitive information. Privacy policies play an important role in addressing users’ privacy concerns and developers are required to provide privacy policies to disclose their apps’ data practices. In addition, voice apps targeting users in European countries are required to comply with the GDPR (General Data Protection Regulation). However, little is known about whether these privacy policies are informative and trustworthy on emerging …


Optimization Strategies For Political Redistricting, Blake Splitter Aug 2024

Optimization Strategies For Political Redistricting, Blake Splitter

All Dissertations

Political redistricting has remained a hot-button issue in the United States for several decades. Every ten years, most states need to redraw their districts to account for changing populations. Sometimes, these district plans can be drawn with the malevolent intention of aiding one political party over another. This dissertation summarizes four distinct methods of drawing these districts using computer algorithms while keeping several objectives in mind. We test these approaches on the case study state of South Carolina, since it provides a sufficiently challenging problem for us to test various algorithms. We find that many of these approaches improve upon …


Optimization Strategies To Enhance Performance In Matrix/Tensor Factorization And Multi-Source Data Integration, Mengyuan Zhang Aug 2024

Optimization Strategies To Enhance Performance In Matrix/Tensor Factorization And Multi-Source Data Integration, Mengyuan Zhang

All Dissertations

Optimization in the realm of machine learning constitutes a fundamental process aimed at refining the parameters of models to enhance their performance. It serves as the backbone of various machine learning techniques, encompassing diverse algorithms and methodologies tailored to address specific tasks and objectives.

In machine learning, datasets are commonly structured as matrices or tensors, making techniques like matrix factorization and tensor factorization indispensable for extracting meaningful representations from intricate data. Furthermore, datasets commonly comprise multiple sets of features, which has inspired our exploration of effective strategies for leveraging information from diverse sources during optimization. Additionally, the interconnected nature of …


Some Experiments In Additive Number Theory, Yunan Wang Aug 2024

Some Experiments In Additive Number Theory, Yunan Wang

All Dissertations

This dissertation explores fundamental conjectures in number theory, focusing on the distribution patterns of representation functions in prime pairs. The work concentrates on twin primes, cousin primes, and primes separated by six units, offering a fresh heuristic interpretation of the Hardy-Littlewood correction factor. The analysis progresses to investigate the partition function for prime pairs in the form $(p, p+k)$, specifically for $k = 2, 4, 6$. The study culminates in the derivation of a general formula for prime pairs $(p, p+d)$, where $d$ is an even integer. Drawing on the insights gleaned from examining the correction factor, this dissertation proposes …


We Train Ai, Why Not Humans, Too? An Exploration Of Human-Ai Team Training For Future Workplace Viability, Caitlin M. Lancaster Aug 2024

We Train Ai, Why Not Humans, Too? An Exploration Of Human-Ai Team Training For Future Workplace Viability, Caitlin M. Lancaster

All Dissertations

The integration of Artificial Intelligence (AI) in the workforce is transforming team dynamics, leading to the emergence of Human-AI Teams (HATs). These teams offer opportunities to capitalize on human strengths with AI's prowess, offering significant opportunities for innovation and efficiency. Effective HAT functioning requires aligning human expectations with AI capabilities and bridging knowledge gaps between teammates. Despite this potential, key integration challenges remain, such as developing shared mental models, addressing skill limitations, and overcoming negative AI perceptions. Existing training efforts often apply human-human teaming principles directly to HATs, overlooking AI's role as a teammate and limiting the development of HAT-specific …


Relating Elasticity And Other Multiplicative Properties Among Orders In Number Fields And Related Rings, Grant Moles Aug 2024

Relating Elasticity And Other Multiplicative Properties Among Orders In Number Fields And Related Rings, Grant Moles

All Dissertations

This dissertation will explore factorization within orders in a number ring. By far the most well-understood of these orders are rings of algebraic integers. We will begin by examining how certain types of subrings may relate to the larger rings in which they are contained. We will then apply this knowledge, along with additional techniques, to determine how the elasticity in an order relates to the elasticity of the full ring of algebraic integers. Using many of the same strategies, we will develop a corresponding result in the rings of formal power series. Finally, we will explore a number of …


Efficient First-Order Methods For Some Smooth Nonlinear Optimization Problems, Yunheng Jiang Aug 2024

Efficient First-Order Methods For Some Smooth Nonlinear Optimization Problems, Yunheng Jiang

All Dissertations

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Physics-Informed Machine Learning Methods For Inverse Design Of Multi-Phase Materials With Targeted Mechanical Properties, Yunpeng Wu Aug 2024

Physics-Informed Machine Learning Methods For Inverse Design Of Multi-Phase Materials With Targeted Mechanical Properties, Yunpeng Wu

All Dissertations

Advances in machine learning algorithms and applications have significantly enhanced engineering inverse design capabilities. This work focuses on the machine learning-based inverse design of material microstructures with targeted linear and nonlinear mechanical properties. It involves developing and applying predictive and generative physics-informed neural networks for both 2D and 3D multiphase materials.

The first investigation aims to develop a machine learning method for the inverse design of 2D multiphase materials, particularly porous materials. We first develop machine learning methods to understand the implicit relationship between a material's microstructure and its mechanical behavior. Specifically, we use ResNet-based models to predict the elastic …


Probabilistic Frames And Concepts From Optimal Transport, Dongwei Chen Aug 2024

Probabilistic Frames And Concepts From Optimal Transport, Dongwei Chen

All Dissertations

As the generalization of frames in the Euclidean space $\mathbb{R}^n$, a probabilistic frame is a probability measure on $\mathbb{R}^n$ that has a finite second moment and whose support spans $\mathbb{R}^n$. The p-Wasserstein distance with $p \geq 1$ from optimal transport is often used to compare probabilistic frames. It is particularly useful to compare frames of various cardinalities in the context of probabilistic frames. We show that the 2-Wasserstein distance appears naturally in the fundamental objects of frame theory and draws consequences leading to a geometric viewpoint of probabilistic frames.

We convert the classic lower bound estimates of 2-Wasserstein distance \cite{Gelbrich90, …


On Weak Solutions And The Navier-Stokes Equations, Aryan Prabhudesai Aug 2024

On Weak Solutions And The Navier-Stokes Equations, Aryan Prabhudesai

Mathematical Sciences Undergraduate Honors Theses

In this paper, I will discuss a partial differential equation that has solutions that are discontinuous. This example motivates the need for distribution theory, which will provide an interpretation of what it means for a discontinuous function to be a “solution” to a PDE. Then I will give a detailed foundation of distributions, including the definition of the derivative of a distribution. Then I will introduce and give background on the Navier-Stokes equations. Following that, I will explain the Millennium Problem concerning global regularity for the Navier-Stokes equations and share mathematical results regarding weak solutions. Finally, I will go over …


Assessing The Reactivity Of Amino Acids To Chlorination Using Capillary Electrophoresis, Pedro De Allende Aug 2024

Assessing The Reactivity Of Amino Acids To Chlorination Using Capillary Electrophoresis, Pedro De Allende

Electronic Theses, Projects, and Dissertations

Amino acids (AA) are ubiquitous in wastewater systems. One of the most popular wastewater treatments is chlorination which is effective at eradicating bacteria and overall treating the wastewater, but it can also produce disinfection by-products (DBPs). Certain DBPs have been classified as Class B Carcinogens to humans and are therefore highly regulated and monitored. Past studies have shown that natural organic matter (NOM), specifically amino acids, can be precursors to DBPs if chlorinated to the correct dose. This thesis project explored AA chlorination's mechanism(s) to understand further which products arise. In particular, the investigation detailed which steps of the mechanism …


Enhancing Cybersecurity For Unmanned Systems: A Comprehensive Literature Review, Jonathan Gabriel Mardoyan Aug 2024

Enhancing Cybersecurity For Unmanned Systems: A Comprehensive Literature Review, Jonathan Gabriel Mardoyan

Electronic Theses, Projects, and Dissertations

This culminating experience project addresses the pressing cybersecurity challenges encountered by unmanned autonomous vehicles. The research provides a comprehensive literature review on how hybrid encryption techniques can improve the security of its communication systems. The chosen research questions guiding this study are: (Q1) How can we enhance cybersecurity measures to safeguard the communication and transmission of sensitive data from unmanned systems, thereby preventing unauthorized access by malicious actors? (Q2) How can we ensure the confidentiality and integrity of messages exchanged with unmanned systems to a command-and-control center operating on the tactical edge? (Q3) How can hybrid encryption tackle the consumption …


Exploring Intraplate Seismicity In The Midwest, Alexa Fernández Aug 2024

Exploring Intraplate Seismicity In The Midwest, Alexa Fernández

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Intraplate seismicity represents a notable occurrence within the stable North American Craton. This research explores the potential sources of stresses that could reactivate older faults and influence seismic activity within this region. Among these sources, the enduring impact of the last glacial period is considered, which includes continued glacial isostatic adjustments (GIA). During GIA the lithosphere rebounds due to the retreating ice, and the forebulge caused by far-field flexure in response to the glacial load, collapses. This results in significant faulting, fracturing, and seismic activity associated with the deglaciation phase. The adjustment of the lithosphere manifests as both near surface …


Instantons In Φ4 Theories: Transseries, Virial Theorems, And Numerical Aspects, Ludovico T. Giorgini, Ulrich D. Jentschura, Enrico M. Malatesta, Tommaso Rizzo, Jean Zinn-Justin Aug 2024

Instantons In Φ4 Theories: Transseries, Virial Theorems, And Numerical Aspects, Ludovico T. Giorgini, Ulrich D. Jentschura, Enrico M. Malatesta, Tommaso Rizzo, Jean Zinn-Justin

Physics Faculty Research & Creative Works

We discuss numerical aspects of instantons in two- and three-dimensional φ4 theories with an internal O(N) symmetry group, the so-called N-vector model. By combining asymptotic transseries expansions for large arguments with convergence acceleration techniques, we obtain high-precision values for certain integrals of the instanton that naturally occur in loop corrections around instanton configurations. Knowledge of these numerical properties is necessary in order to evaluate corrections to the large-order factorial growth of perturbation theory in φ4 theories. The results contribute to the understanding of the mathematical structures underlying the instanton configurations.


Perturbative Versus Non-Perturbative Renormalization, S. Hariharakrishnan, Ulrich D. Jentschura, I. G. Marian, K. Szabo, I. Nandori Aug 2024

Perturbative Versus Non-Perturbative Renormalization, S. Hariharakrishnan, Ulrich D. Jentschura, I. G. Marian, K. Szabo, I. Nandori

Physics Faculty Research & Creative Works

Approximated functional renormalization group (FRG) equations lead to regulator-dependent β-functions, in analogy to the scheme-dependence of the perturbative renormalization group (pRG) approach. A scheme transformation redefines the couplings to relate the β-functions of the FRG method with an arbitrary regulator function to the pRG ones obtained in a given scheme. Here, we consider a periodic sine-Gordon scalar field theory in d = 2 dimensions and show that the relation of the FRG and pRG approaches is intricate. Although both the FRG and the pRG methods are known to be sufficient to obtain the critical frequency β c 2 = 8 …


Doubly Differential Cross Sections For Ionization In Proton Collisions With Atomic Hydrogen: Energy And Angular Distribution Of Emitted Electrons, C. T. Plowman, K. H. Spicer, N. W. Antonio, M. S. Schöffler, Michael Schulz, I. Bray, A. S. Kadyrov Aug 2024

Doubly Differential Cross Sections For Ionization In Proton Collisions With Atomic Hydrogen: Energy And Angular Distribution Of Emitted Electrons, C. T. Plowman, K. H. Spicer, N. W. Antonio, M. S. Schöffler, Michael Schulz, I. Bray, A. S. Kadyrov

Physics Faculty Research & Creative Works

We use the two-center wave-packet convergent close-coupling approach to ion-atom collisions to calculate the energy and angular distribution of electrons emitted in proton collisions with atomic hydrogen. Results are provided across a wide range of intermediate energies where many competing reaction channels make calculations challenging. The present data consistently agree with the available experimental measurements and improve upon previously available results based on perturbative and classical methods. Furthermore, we extend the range of electron angles and energies over which theoretical data are available for the doubly differential cross section for ionization. This provides strong evidence that at the level of …


Methods For Improving Low Frequency Selection And Electrode Firing Order In Cochlear Implants, James H. Keen Jr. Aug 2024

Methods For Improving Low Frequency Selection And Electrode Firing Order In Cochlear Implants, James H. Keen Jr.

University of New Orleans Theses and Dissertations

The Advanced Bionics cochlear implant devices allocate static frequency bins to electrode channels based on the natural tonotopic organization of the cochlea. These frequency bins are wide and limited, especially in the lower range. Considering that the fundamental tones of the human voice and the primary melodic tones in music are in this lower range, it is important to have accurate representation of this frequency content. Here, adjustments to the frequency bin allocation algorithm used in the crowdsourced CI Hackathon code are made to allow a more accurate representation of the original signal. First, the frequency bins allocated to each …