Digital Commons Network^™

Static And Dynamical Properties Of Multiferroics, Sayed Omid Sayedaghaee

Graduate Theses and Dissertations

Since the silicon industrial revolution in the 1950s, a lot of effort was dedicated to the research and development activities focused on material and solid-state sciences. As a result, several cutting-edge technologies are emerging including the applications of functional materials in the design and enhancement of novel devices such as sensors, highly capable data storage media, actuators, transducers, and several other types of electronic tools. In the last two decades, a class of functional materials known as multiferroics has captured significant attention because of providing a huge potential for new designs due to possessing multiple ferroic order parameters at the …

A Mixed-Methods Analysis Of Biofuels, Teresa Cristina Garcia

Graduate Theses and Dissertations

Brazil has the largest sugarcane acreage in the world (FAOSTAT, 2020) and is the world leader in the production of sugarcane-based ethanol (Sousa Junior et al., 2017). Due to the technical experience in the production of biofuels and the availability of sugarcane straw and bagasse, the country has a great potential to commercially produce second-generation ethanol (E2G) (Nyko et. al., 2010). In 2017, Brazil enacted a new National Biofuels Policy, called RenovaBio, to expand the production and use of biofuels in the country. This dissertation combines three essays that explore biofuels law and policy with a special focus on Brazil. …

Paleotectonic Investigation By Successive 3d Seismic Horizon Flattening In The Pennsylvanian Interval Of Western Osage County, Oklahoma, Douglas Cooper Mccabe

Graduate Theses and Dissertations

3D seismic and well log data in Western Osage County, Oklahoma, are utilized to evaluate possible intracratonic tectonic signals present in the subsurface stratigraphy of the Cherokee Platform as a result of the regional tectonic events of Pennsylvanian age. These events include: the Wichita, Ouachita, and Arbuckle orogenies, the Nemaha and Ozark Uplifts, and the Southeast Oklahoma Aulacogen. Horizon flattening within 3D seismic volumes allows for identification of paleotectonic structures and syntectonic depositional features, which may be related to the collateral effects of these orogenies on the Cherokee Platform. Identified structures were assigned geologic ages using precision synthetic seismograms tuned …

Elementary Teachers’ Experiences With Remote Learning And Its Impact On Science Instruction: Multiple Cases From The Early Response To The Covid-19 Pandemic, Beth Pesnell

Graduate Theses and Dissertations

Teachers across the United States and worldwide found themselves in unprecedented educational situations during the early response period to the COVID-19 pandemic in spring of 2020. Efforts to quarantine and provide social distancing to prevent the spread of the disease brought mandated school closures throughout the United States, and teachers were required to pivot from their traditional, in-person instructional methods and deliver instruction remotely. This phenomenological multiple-case study explored the experiences of 10 elementary teachers with remote learning during the early response period and sought to understand the delivery of science instruction in the remote learning experience. Weekly interviews were …

Development Of An Effect Size To Classify The Magnitude Of Dif In Dichotomous And Polytomous Items, James D. Weese

Graduate Theses and Dissertations

A standardized effect size for the SIBTEST/POLYSIBTEST procedure is proposed, allowing for Differential Item Functioning (DIF) to be classified with a single set of DIF heuristics regardless of whether data are dichotomous or polytomous. This proposed standardized effect size accounts for both variability in responses and whether participants are included in the SIBTEST/POLYSIBTEST calculations. First, a new set of unstandardized effect size heuristics are established for dichotomous data that are more aligned with Educational Testing Service (ETS) standards using two and three parameter logistic (2PL and 3PL) models. Second, a standardized effect size is proposed and compared to other DIF …

Neogene And Quaternary Events Shaped Diversification And Speciation In Bhutanese Rheophilic Fishes Of The Family Nemacheilidae (Cypriniformes) And Sisoridae (Siluriformes), Karma Wangchuk

Graduate Theses and Dissertations

Biogeography of the Himalayan region [to include the Qinghai-Tibetan Plateau (QTP)] evolved over a ~30M year span, catalyzed by the collision of the Indian and Eurasian plates. The resulting uplift produced major ecological and climatic effects, that in turn drove the diversification of biodiversity. As a result, the QTP is designated as a global biodiversity hotspot particularly vulnerable to cumulative climatic effects, including shrinking distributions, declining numbers, and local extinctions. Understanding how the biodiversity within the Himalaya/ QTP was established and maintained is a necessary first step in prioritizing conservation efforts.

Fishes in global montane regions, such as the Himalaya, …

Fourier Transform Infrared Spectroscopy For The Measurement Of Gesn/(Si)Gesn, Solomon Opeyemi Ojo

Graduate Theses and Dissertations

Photoluminescence (PL) and Electroluminescence (EL) characterization techniques are important tools for studying the optical and electrical properties of (Si)GeSn. Light emission from these PL and EL measurements provides relevant information on material quality, bandgap energy, current density, and device efficiency. Prior to this work, the in-house PL set-up of this lab which involves the use of a commercially-obtained dispersive spectrometer was used for characterizing both GeSn thin film and fabricated devices, but these measurements were limited by issues bordering on low spectral resolution, spectral artifacts, and poor signal-to-noise ratio (SNR) thereby resulting in the possible loss of vital information and …

Association Mapping For Soybean (Glycine Max L. Merr.) Protein And Oil Content, Joseph Najjar

Graduate Theses and Dissertations

Soybean [Glycine Max (L.) Merrill] is an important economic crop because of its high content of seed protein and oil. Seed oil and protein content are quantitative inherited traits. The genetics of seed protein and oil levels have been extensively studied, with 367 QTL reported for protein and 475 QTL reported for oil to date. Validation of such QTLs, and identification of easily-automatable molecular markers around these QTL will aid the progression of breeding for such traits. The focus of this research was to discover novel and verify previously reported QTL related to protein and/or oil content via Genome-Wide Association …

Applications Of Cathodoluminescence In Plasmonic Nanostructures And Ultrathin Inas Quantum Layers, Qigeng Yan

Graduate Theses and Dissertations

Due to the advanced focusing ability, characterization methods based on the electron-beam excitation have been broadly applied to investigate nanomaterials. Structural or compositional information is commonly acquired using electron microscopes. Moreover, taking advantage of the super spatial resolution of the focused electron beam, optical properties of nanomaterials can be also obtained. Herein, general concepts and processes of the interaction between electrons and materials are studied. Two specific optical nanomaterials, including plasmonic nanostructures and semiconductor quantum layers, are investigated by the cathodoluminescence (CL) measurement.

Surface plasmonic resonance can be generated when high-energy electrons strike the interface between the dielectric medium and …

Design And Evaluation Of High Power, High Efficiency And High Power Density Motor Drives For More Electric Aircrafts, Zhao Yuan

Graduate Theses and Dissertations

More-electric aircraft (MEA) is an attractive concept as it can reduce carbon dioxide emission, relieve fossil-fuel consumption, improve the overall efficiency of aircraft, and reduce the operational costs. However, it poses substantial challenges in designing a high-performance motor drive system for such applications. In the report of Aircraft Technology Roadmap to 2050, the propulsion converter is required to be ultra-high efficiency, high power density, and high reliability. Though the wide band-gap devices, such as the Silicon-carbide based Metal Oxide Silicon Field Effect (SiC-MOSFET), shows better switching performance and improved high-temperature performance compared to the silicon counterparts, applying it to the …

Seismic Expressions Of Paleokarst, Olanrewaju Ayodapo Aboaba

Graduate Theses and Dissertations

Paleokarst are characterized by epigene and/or hypogene processes in their formation and hold significant numbers of hydrocarbons and other natural resources. This dissertation examines worldwide seismic expression of paleokarst; and specifically, the characterization of paleokarst reservoirs developed across the Cherokee Platform, and in the Arkoma Basin, Oklahoma.

Worldwide subsurface paleokarst formations are of Precambrian to Miocene age and found at depths less than 200 m to as great as 8000 m. Karst can be are expressed on seismic records as sinkholes, paleocave collapse, and tower morphologies. Seismic modeling indicates that karst can be modeled and imaged to better understand its …

Framework Grain Composition And Texture Of The Wedington Sandstone Member, Fayetteville Shale, As A Provenance And Sediment Dispersal Indicator For Clastic Depositional Systems Across The Northern Arkansas Structural Platform During The Late Mississippian, Tanner Wayne Corbin

Graduate Theses and Dissertations

The Wedington Sandstone Member of the Fayetteville Shale is a constructive delta complex in the Chesterian section of the Late Mississippian record in Northwest Arkansas. A comparative analysis of framework grain composition between the Wedington and two other stratigraphically proximal Carboniferous sandstones: the Batesville Sandstone (older) and the Basal Atoka-Spiro Sandstone (younger) has addressed three questions: 1) Is there similarity in sediment provenance for the three sandstones? 2) Do these three sandstone units have a similar sediment dispersal vector? 3) What are likely sediment source terrains for the Wedington Sandstone? Wedington samples overwhelmingly plot as quartzarenites with fewer samples plotting …

Multi-Proxy Provenance Evaluation Of The Stevens Sandstone, San Joaquin Basin, California, Charles Adam Ball

Graduate Theses and Dissertations

The Stevens sandstone is a prolific hydrocarbon reservoir in the southern San Joaquin Basin that has produced greater than five billion barrels of oil equivalent and represents an important exploration target. The San Joaquin basin has a complex depositional and structural history related to the overprinting of a Mesozoic-Paleogene forearc basin by transtension and transpression along the San Andreas fault system that presently borders the southwestern side of the basin. The Stevens sandstone consists of quartzo-feldspathic, deep-water turbidite deposits and is primarily confined within the subsurface of the southern San Joaquin basin. Due to this mode of deposition and the …

Ppmexplorer: Using Information Retrieval, Computer Vision And Transfer Learning Methods To Index And Explore Images Of Pompeii, Cindy Roullet

Graduate Theses and Dissertations

In this dissertation, we present and analyze the technology used in the making of PPMExplorer: Search, Find, and Explore Pompeii. PPMExplorer is a software tool made with data extracted from the Pompei: Pitture e Mosaic (PPM) volumes. PPM is a valuable set of volumes containing 20,000 historical annotated images of the archaeological site of Pompeii, Italy accompanied by extensive captions. We transformed the volumes from paper, to digital, to searchable. PPMExplorer enables archaeologist researchers to conduct and check hypotheses on historical findings. We present a theory that such a concept is possible by leveraging computer generated correlations between artifacts using …

Stability Of Group Four Monochalcogenides In Water And Air, William Shattuck

Graduate Theses and Dissertations

Previously published works have simulated the behavior of monolayer group IV monochalcogenides and predicted them to have very useful electronic properties. These simulations have also predicted that monolayers of group IV monochalcogenides will degrade quickly when exposed to water, even in extremely low concentrations. We hypothesize that thin samples of these materials will show signs of degradation if left in air and in water for an extended period of time.

Samples of each of the four monochalcogenides (GeS, GeSe, SnS and SnSe) were exfoliated onto clean oxidized silicon substrates. Chemical analysis showed the SnSe samples were contaminated, so they were …

Rice Chilling Aeration: Assessment Of Impacts On Grain Quality, Process Modeling And Validation, Soraya Shafiekhani

Graduate Theses and Dissertations

The goal of this study is to demonstrate the effectiveness of applying chilling temperatures during on-farm, in-bin drying and storage to maintain rice quality. Specific objectives include to demonstrate the effectiveness of chilling aeration to preserve rice quality characteristics, determine the drying kinetics of rice under low temperature environments, and develop models to predict heat and mass transfer in rice kernel during drying at low temperature environment. To date, there is limited research describing storability or drying behavior of rice in chilled environments. However, it is understood that chilling of high-moisture, > 21% wet basis rough rice could reduce the time …

Projecting Water Available For Irrigation Use And Identifying Water Supply Stress Under Climate Change Scenarios In Selected U.S. Fruit And Vegetable Production Regions, Andrew Shaw

Graduate Theses and Dissertations

Climate change affects water resources differently across geospatial regions in the United States (U.S). There is a concern of how water availability will be affected by changes in long-term temperature and precipitation patterns, specifically in major production regions for eight fruit and vegetable crops. The effects on surface water available for irrigation use and supply stress in five regions containing 31 Agricultural Statistics Districts (ASDs) were assessed. The Water Supply Stress Index Model was used and modified to project water available for irrigation use across nine climate scenarios driven by historical data, five General Circulation Models, two population scenarios, and …

Culturally Responsive Pedagogy And Writing Achievement For Native High School Students, Angelia Christine Greiner

Graduate Theses and Dissertations

This study focuses on the effects of culturally responsive pedagogy as it is implemented in a high school classroom with Native American students. This mixed methods case study collects, analyzes and synthesizes both quantitative and qualitative data within an overall formative and experimental design approach to measure the effects of culturally responsive pedagogy on students’ writing and their attitudes about writing. The study identified specific approaches to literacy instruction that hold promise for engaging Native students. Furthermore, findings from the study reveal the use of visual art as a particularly powerful tool that extends students’ meaning-making skills, leading to more …

Exploring Sediment Compaction In Experimental Deltas: Towards A Meso-Scale Understanding Of Coastal Subsidence Patterns, Samuel Mason Zapp

Graduate Theses and Dissertations

Subsidence in low elevation coastal areas has been extensively researched through direct field measurement, numerical modelling, and stratigraphic reconstruction of ancient sediment deposits. Here I present the first investigation of subsidence due to sediment compaction and consolidation in two laboratory scale river delta experiments. Compactional subsidence rates have never been thoroughly quantified in the experimental setting, though this mechanism is found to be a primary creator of total relative sea level rise which will likely cause coastlines to retreat in the coming years. Spatial and temporal trends in subsidence rates in the experimental setting may elucidate behavior which cannot be …

Introduction To Neutrosophic Genetics, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophic Genetics is the study of genetics using neutrosophic logic, set, probability, statistics, measure and other neutrosophic tools and procedures. In this paper, based on the Neutrosophic Theory of Evolution (that includes degrees of Evolution, Neutrality (or Indeterminacy), and Involution) – as extension of Darwin’s Theory of Evolution, we show the applicability of neutrosophy in genetics, and we present within the frame of neutrosophic genetics the following concepts: neutrosophic mutation, neutrosophic speciation, and neutrosophic coevolution.

Female Enrolments In Stem In Higher Education: Trend Analysis From 2003 – 2018: Knust As A Case Study, Mercy Vanessa D. Appiah-Castel,, Richard Bruce Lamptey, Kemi Titiloye, Welhemina Adoma Pels

Library Philosophy and Practice (e-journal)

Tertiary education in Ghana has experienced rapid growth in accessibility and participation. It is evident that Ghana has made some positive and impressive progress towards increasing access to education and narrowing gender gaps at the pre-tertiary education levels, yet these developments have not translated commensurately in higher education level. This study investigates the effectiveness of the directives and the Vice-Chancellors' initiatives introduced and designed to increase female students' enrolment at the Kwame Nkrumah University of Science and Technology (KNUST). The study used enrolment data from KNUST, the university’s initiatives and directives on female enrolments, KNUST recorders, online articles, publications and …

Why School Libraries Remain Underdeveloped In Nigeria, And The Way Forward, Olabode Olajide Mr, Sandy Zinn Prof

Library Philosophy and Practice (e-journal)

Applying the lens of constructivism and inquiry-based learning, this study investigated why libraries remain underdeveloped in Nigerian schools, and the way forward. The study was motivated by the importance accorded to school libraries, being one of the most important educational services that could be used to achieve good standard education in Nigeria. The methodological approach adopted for this study was mixed methods. The study’s population comprised “school librarians”, principals, and science teachers in public senior secondary schools as well as major stakeholders in education connected with the provision, management and utilization of library resources for teaching science subjects. The instruments …

Perceived Research Skills Of Graduating Library And Information Science (Lis) Undergraduates In A Nigerian University Of Education, Anuoluwa Feyikemi Awodoyin Dr., Niran Adetoro Prof, Precious Oke Miss

Library Philosophy and Practice (e-journal)

Researchers in institutions of higher learning are required to conduct researches that will expand the frontiers of knowledge, drive innovation in industries, and the economy at large. Consequently, research has become an integral component of a university’s curriculum. However, there is an ‘assumption’ that undergraduates possess requisite research skills at the end of their training due to their exposure to research. To ascertain this, this study investigated the perceived research skills of graduating Library and Information Science (LIS) undergraduates in a Nigerian University of Education. The study is a survey of the ex post facto type. Total enumeration was used …

Variational Bayesian Inference For Crowdsourcing Predictions, Desmond Cai, Duc Thien Nguyen, Shiau Hong Lim, Laura Wynter

Research Collection School Of Computing and Information Systems

Crowdsourcing has emerged as an effective means for performing a number of machine learning tasks such as annotation and labelling of images and other data sets. In most early settings of crowdsourcing, the task involved classification, that is assigning one of a discrete set of labels to each task. Recently, however, more complex tasks have been attempted including asking crowdsource workers to assign continuous labels, or predictions. In essence, this involves the use of crowdsourcing for function estimation. We are motivated by this problem to drive applications such as collaborative prediction, that is, harnessing the wisdom of the crowd to …

Fractional Nonlinear Volterra–Fredholm Integral Equations Involving Atangana–Baleanu Fractional Derivative: Framelet Applications, Mutaz Mohammad, Alexander Trounev

All Works

© 2020, The Author(s). In this work, we propose a framelet method based on B-spline functions for solving nonlinear Volterra–Fredholm integro-differential equations and by involving Atangana–Baleanu fractional derivative, which can provide a reliable numerical approximation. The framelet systems are generated using the set of B-splines with high vanishing moments. We provide some numerical and graphical evidences to show the efficiency of the proposed method. The obtained numerical results of the proposed method compared with those obtained from CAS wavelets show a great agreement with the exact solution. We confirm that the method achieves accurate, efficient, and robust measurement.

Improving Gan Training With Probability Ratio Clipping And Sample Reweighting, Yue Wu, Pan Zhou, Andrew Wilson Gordon, Eric Xing, Zhiting Hu

Research Collection School Of Computing and Information Systems

Despite success on a wide range of problems related to vision, generative adversarial networks (GANs) often suffer from inferior performance due to unstable training, especially for text generation. To solve this issue, we propose a new variational GAN training framework which enjoys superior training stability. Our approach is inspired by a connection of GANs and reinforcement learning under a variational perspective. The connection leads to (1) probability ratio clipping that regularizes generator training to prevent excessively large updates, and (2) a sample re-weighting mechanism that improves discriminator training by downplaying bad-quality fake samples. Moreover, our variational GAN framework can provably …

Heterogeneous Univariate Outlier Ensembles In Multidimensional Data, Guansong Pang, Longbing Cao

Research Collection School Of Computing and Information Systems

In outlier detection, recent major research has shifted from developing univariate methods to multivariate methods due to the rapid growth of multidimensional data. However, one typical issue of this paradigm shift is that many multidimensional data often mainly contains univariate outliers, in which many features are actually irrelevant. In such cases, multivariate methods are ineffective in identifying such outliers due to the potential biases and the curse of dimensionality brought by irrelevant features. Those univariate outliers might be well detected by applying univariate outlier detectors in individually relevant features. However, it is very challenging to choose a right univariate detector …

Audee: Automated Testing For Deep Learning Frameworks, Qianyu Guo, Xiaofei Xie, Yi Li, Xiaoyu Zhang, Yang Liu, Xiaohong Li, Chao Shen

Research Collection School Of Computing and Information Systems

Deep learning (DL) has been applied widely, and the quality of DL system becomes crucial, especially for safety-critical applications. Existing work mainly focuses on the quality analysis of DL models, but lacks attention to the underlying frameworks on which all DL models depend. In this work, we propose Audee, a novel approach for testing DL frameworks and localizing bugs. Audee adopts a search-based approach and implements three different mutation strategies to generate diverse test cases by exploring combinations of model structures, parameters, weights and inputs. Audee is able to detect three types of bugs: logical bugs, crashes and Not-a-Number (NaN) …

Enabling Collaborative Video Sensing At The Edge Through Convolutional Sharing, Kasthuri Jayarajah, Wanniarachchige Dhanuja Tharith Wanniarachchi, Archan Misra

Research Collection School Of Computing and Information Systems

While Deep Neural Network (DNN) models have provided remarkable advances in machine vision capabilities, their high computational complexity and model sizes present a formidable roadblock to deployment in AIoT-based sensing applications. In this paper, we propose a novel paradigm by which peer nodes in a network can collaborate to improve their accuracy on person detection, an exemplar machine vision task. The proposed methodology requires no re-training of the DNNs and incurs minimal processing latency as it extracts scene summaries from the collaborators and injects back into DNNs of the reference cameras, on-the-fly. Early results show promise with improvements in recall …

Interventional Few-Shot Learning, Zhongqi Yue, Zhang Hanwang, Qianru Sun, Xian-Sheng Hua

Research Collection School Of Computing and Information Systems

We uncover an ever-overlooked deficiency in the prevailing Few-Shot Learning (FSL) methods: the pre-trained knowledge is indeed a confounder that limits the performance. This finding is rooted from our causal assumption: a Structural Causal Model (SCM) for the causalities among the pre-trained knowledge, sample features, and labels. Thanks to it, we propose a novel FSL paradigm: Interventional Few-Shot Learning (IFSL). Specifically, we develop three effective IFSL algorithmic implementations based on the backdoor adjustment, which is essentially a causal intervention towards the SCM of many-shot learning: the upper-bound of FSL in a causal view. It is worth noting that the contribution …