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Articles 1291 - 1320 of 4195

Full-Text Articles in Physical Sciences and Mathematics

The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani Jan 2019

The Effect Of Edge-Of-Field Nutrient Management Practices On Microbial Concentrations In Subsurface Drainage Water And The Associated Risk Of Antibiotic Resistance Dissemination, Sara Mardani

Electronic Theses and Dissertations

Many in-field and edge-of-field management practices have been used to reduce nutrient loads from agricultural fields. The denitrification woodchip bioreactor (WB) is one edgeof- field management practice that has proven to be effective in removing nitrate from subsurface drainage water. The success in nitrate removal achieved with WBs has raised interest in expanding their capabilities for removing other agricultural pollutants, including phosphorus, by using other types of media like phosphorus-sorbing filters or combining these filters with woodchips to remove both nitrate and phosphorus as dual-nutrient removal systems. Despite the extensive research done on WBs and nutrient filter materials, little consideration …


Evaluating Green Solvents And Techniques In Extraction Methods, Shanmugapriya Dharmarajan Jan 2019

Evaluating Green Solvents And Techniques In Extraction Methods, Shanmugapriya Dharmarajan

Electronic Theses and Dissertations

Of all analytical techniques, extraction is a huge solvent-consuming process that could adversely impact the environment. Use of petroleum-based solvents for extraction of oilseeds is still a common practice, despite the potential fire hazard and the toxic water pollution. The rising awareness of chemical activities created immense need for sustainable development schemes and strategies that should address the environmental impact without compromising the yield. In the course of developing green extraction techniques, automation, alternative solvents, and selective extractions are the growing trend. This dissertation aligns with that progress by surveying green solvents, comparing their performance during oil extraction, examining a …


Instance Segmentation And Object Detection In Road Scenes Using Inverse Perspective Mapping Of 3d Point Clouds And 2d Images, Chungyup Lee Jan 2019

Instance Segmentation And Object Detection In Road Scenes Using Inverse Perspective Mapping Of 3d Point Clouds And 2d Images, Chungyup Lee

Electronic Theses and Dissertations

The instance segmentation and object detection are important tasks in smart car applications. Recently, a variety of neural network-based approaches have been proposed. One of the challenges is that there are various scales of objects in a scene, and it requires the neural network to have a large receptive field to deal with the scale variations. In other words, the neural network must have deep architectures which slow down computation. In smart car applications, the accuracy of detection and segmentation of vehicle and pedestrian is hugely critical. Besides, 2D images do not have distance information but enough visual appearance. On …


Applying Machine Learning Algorithms For The Analysis Of Biological Sequences And Medical Records, Shaopeng Gu Jan 2019

Applying Machine Learning Algorithms For The Analysis Of Biological Sequences And Medical Records, Shaopeng Gu

Electronic Theses and Dissertations

The modern sequencing technology revolutionizes the genomic research and triggers explosive growth of DNA, RNA, and protein sequences. How to infer the structure and function from biological sequences is a fundamentally important task in genomics and proteomics fields. With the development of statistical and machine learning methods, an integrated and user-friendly tool containing the state-of-the-art data mining methods are needed. Here, we propose SeqFea-Learn, a comprehensive Python pipeline that integrating multiple steps: feature extraction, dimensionality reduction, feature selection, predicting model constructions based on machine learning and deep learning approaches to analyze sequences. We used enhancers, RNA N6- methyladenosine sites and …


Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan Jan 2019

Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan

Electronic Theses and Dissertations

A major constraint of beef production within the Standing Rock Reservation has been identified as a reduction in rangeland quality due in large part to wide-scale colonization by black-tailed prairie dogs (Cynomys ludovicianus). The desire exists within the community to design a holistic framework which incorporates livestock management with the goal of increasing production and rangeland health while still maintaining increased diversity associated with prairie dogs. Prairie dogs reduce the carrying capacity of cattle on rangelands by up to 50% on occupied hectares through direct consumption of vegetation and waste due to clipping to improve detection of predators. Livestock stocking …


An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood Jan 2019

An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood

Electronic Theses and Dissertations

Nitrogen and phosphorus are often the limiting nutrients for marine and freshwater systems respectively. Additionally, stormwater often contains elevated levels of pathogens which can pollute the receiving water body and impact reuse applications [1-4]. The reduction of limiting nutrients and pathogens is a common primary target for stormwater best management practices (BMPs) [5]. Traditional BMPs, such as retention/detention treatment ponds require large footprints and may not be practical in ultra-urban environments where above ground space is limited. Upflow filters utilizing biosorption activated media (BAM) that can be placed underground offer a small footprint alternative. Additionally, BAM upflow filters can be …


Visual-Textual Video Synopsis Generation, Aidean Sharghi Karganroodi Jan 2019

Visual-Textual Video Synopsis Generation, Aidean Sharghi Karganroodi

Electronic Theses and Dissertations

In this dissertation we tackle the problem of automatic video summarization. Automatic summarization techniques enable faster browsing and indexing of large video databases. However, due to the inherent subjectivity of the task, no single video summarizer fits all users unless it adapts to individual user's needs. To address this issue, we introduce a fresh view on the task called "Query-focused'' extractive video summarization. We develop a supervised model that takes as input a video and user's preference in form of a query, and creates a summary video by selecting key shots from the original video. We model the problem as …


Broadband Mid-Infrared Frequency Combs Generated Via Frequency Division, Qitian Ru Jan 2019

Broadband Mid-Infrared Frequency Combs Generated Via Frequency Division, Qitian Ru

Electronic Theses and Dissertations

Frequency combs have revolutionized metrology and demonstrated numerous applications in science and technology. Combs operating in the mid-infrared region could be beneficial for molecular spectroscopy for several reasons. First, numerous molecules have their spectroscopic signatures in this region. Furthermore, the atmospheric window (3-5μm and 8-14μm) is located here. Additionally, a mid-infrared frequency comb could be employed as a diagnostic tool for the many components of human breath, as well as for detection of harmful gases and contaminants in the atmosphere. In this thesis, I used synchronously pumped subharmonic optical parametric oscillators (OPOs) operating at degeneracy to produce ultra-broadband outputs near …


Blockchain-Driven Secure And Transparent Audit Logs, Ashar Ahmad Jan 2019

Blockchain-Driven Secure And Transparent Audit Logs, Ashar Ahmad

Electronic Theses and Dissertations

In enterprise business applications, large volumes of data are generated daily, encoding business logic and transactions. Those applications are governed by various compliance requirements, making it essential to provide audit logs to store, track, and attribute data changes. In traditional audit log systems, logs are collected and stored in a centralized medium, making them prone to various forms of attacks and manipulations, including physical access and remote vulnerability exploitation attacks, and eventually allowing for unauthorized data modification, threatening the guarantees of audit logs. Moreover, such systems, and given their centralized nature, are characterized by a single point of failure. To …


Correctness And Progress Verification Of Non-Blocking Programs, Christina Peterson Jan 2019

Correctness And Progress Verification Of Non-Blocking Programs, Christina Peterson

Electronic Theses and Dissertations

The progression of multi-core processors has inspired the development of concurrency libraries that guarantee safety and liveness properties of multiprocessor applications. The difficulty of reasoning about safety and liveness properties in a concurrent environment has led to the development of tools to verify that a concurrent data structure meets a correctness condition or progress guarantee. However, these tools possess shortcomings regarding the ability to verify a composition of data structure operations. Additionally, verification techniques for transactional memory evaluate correctness based on low-level read/write histories, which is not applicable to transactional data structures that use a high-level semantic conflict detection. In …


Use Of Seismic Refraction In Determining Rock Mass Anisotropy, Mohammad Najmush Sakib Oyan Jan 2019

Use Of Seismic Refraction In Determining Rock Mass Anisotropy, Mohammad Najmush Sakib Oyan

Electronic Theses and Dissertations

Seismic refraction is a popular method used by geological/geotechnical engineers to understand subsurface conditions. This method along with information collected from borings produce a realistic image of the ground beneath us. The goal of this study is to define and test a set of procedures to use seismic refraction alone to create high quality images of subsurface conditions. The focus is on areas with several meters of soil overlain by bedrock. The application of these procedures will minimize construction costs by eliminating the need for multiple boreholes. The results show that two important criteria must be met for successful application …


Effects Of Halogen Bonding And Nir Tuning Of Dyes For Dye-Sensitized Solar Cells, Alexandra Baumann Jan 2019

Effects Of Halogen Bonding And Nir Tuning Of Dyes For Dye-Sensitized Solar Cells, Alexandra Baumann

Electronic Theses and Dissertations

With current energy demands being met through the utilization of energy sources such as petroleum, natural gas, and coal, the non-renewable nature of these sources will eventually approach depletion as world wide energy consumption increases yearly. As a result the need for a renewable energy alternative has become imminent. One appealing alternative that has gained considerable attention since its development due to a low cost and a high solar to electric conversion efficiency are dye-sensitized solar cells (DSCs). This dissertation describes efforts to design and synthesize improved organic dyes utilizing three analogous methods: first, through decreasing non-productive pathways such as …


Towards Misleading Connection Mining, Md Main Uddin Rony Jan 2019

Towards Misleading Connection Mining, Md Main Uddin Rony

Electronic Theses and Dissertations

This study introduces a new Natural Language Generation (NLG) task – Unit Claim Identification. The task aims to extract every piece of verifiable information from a headline. The Unit Claim identification has applications in other domains; such as fact-checking where the identification of each verifiable information from a check-worthy statement can lead to an effective fact-check. Moreover, the extracting of the unit claims from headlines can identify a misleading news article, by mapping evidence from contents. For addressing the unit claim identification problem, we outlined a set of guidelines for data annotation, arranged in-house training for the annotators and obtained …


High Voltage Dye-Sensitized Solar Cells And Molecular Photocatalysis For Co2 Reduction, Roberta Ramalho Rodrigues Jan 2019

High Voltage Dye-Sensitized Solar Cells And Molecular Photocatalysis For Co2 Reduction, Roberta Ramalho Rodrigues

Electronic Theses and Dissertations

The development of high voltage solar cells is an attractive way to use sunlight to power electrocatalysts for water oxidation, electrocatalysts for CO2 reduction, and consumer electronics. Through careful molecular dye engineering and redox shuttle pairing, our group has reported a single-junction dye-sensitized solar cell (DSC) employing, for the first time, an iron redox mediator (Fe(bpy)33+/2+) in conjunction with a novel wide band gap dye (RR9). This system generates a high photovoltage of 1.42 V. To the best of our knowledge, this system is the highest photovoltage achieved by a single-junction DSC device without metal oxide doping. The RR9/Fe(bpy)33+/2+ redox …


Ligand Effect On Gold Nanomolecules Demonstrated Using Aliphatic, Aromatic And Bulky Thiolate Ligands, Milan Rambukwella Jan 2019

Ligand Effect On Gold Nanomolecules Demonstrated Using Aliphatic, Aromatic And Bulky Thiolate Ligands, Milan Rambukwella

Electronic Theses and Dissertations

Atomically precise thiolate protected gold nanoparticles (AuNPs) known as gold nanomolecules (AuNMs) are intensely pursued owing to their feasibility to elucidate their structure by single crystal X-ray crystallography. They have distinct number of Au atoms (n) and thiolate (-SR, R-hydrocarbon chain) ligands (m) with molecular formula of the form [Aun(SR)m]. AuNMs are made of a gold core protected by a thiolate-monolayer and possess size-dependent properties conferred by quantum confinement. Atomic precision has been achieved in the 1-3 nm range and crystal structures of several AuNMs ranging from 18 to 279gold atoms have been studied. They provide significant insights into the …


Gravitational Radiation From Superradiant Instabilities Of Rotating Black Holes, Shrobana Ghosh Jan 2019

Gravitational Radiation From Superradiant Instabilities Of Rotating Black Holes, Shrobana Ghosh

Electronic Theses and Dissertations

We use the Teukolsky formalism to calculate the gravitational radiation from a non-axi\-symmetric cloud formed due to superradiant amplification of a spin-0 bosonic field. We focus on the prospects of the future space-based gravitational wave detector, Laser Interferometer Space Antenna (LISA), and the current version of ground-based detector, Advanced Laser Interferometer Gravitational-Wave Observatory (AdLIGO), to detect or constrain scalars with mass in the range $m_s\in [10^{-19},10^{-15}]$ eV and $m_s\in[10^{-14},10^{-11}]$ eV, respectively. Using astrophysical models of black hole populations calibrated to observations we find that, in optimistic scenarios, AdLIGO could detect up to $10^4$ resolvable events in a four-year search if …


Generalized Radial Transport Model For Interpreting Convergent Flow Tracer Tests In Fractured Rock, Md Lal Mamud Jan 2019

Generalized Radial Transport Model For Interpreting Convergent Flow Tracer Tests In Fractured Rock, Md Lal Mamud

Electronic Theses and Dissertations

The double-porosity Generalized Radial Transport (GRT) model is an extension of the generalized radial flow approach developed for hydraulic test interpretation. In both approaches, a flow dimension characterizes the change in flow area versus radial distance from the borehole. The GRT model collapses to a 1D, radial, and spherical advection dispersion equation (ADE) for integer flow dimensions of 1, 2, and 3, respectively. And, the model also transforms to sub-linear, sub-radial, sub-spherical and eventually transform to super-spherical transport model for non-integer flow dimension, n of 0 < n < 1, 1 < n < 2, 2 < n < 3 and n >3 respectively. Non-integer flow dimensions, especially sub-radial, are commonly reported from pumping tests in …


A First-Year Teacher’S Implementation Of Short-Cycle Formative Assessment Through The Use Of A Classroom Response System And Flexible Grouping, Adrienne Irving Dumas Jan 2019

A First-Year Teacher’S Implementation Of Short-Cycle Formative Assessment Through The Use Of A Classroom Response System And Flexible Grouping, Adrienne Irving Dumas

Electronic Theses and Dissertations

As teachers we are tasked with ensuring that our students are equipped with the skills necessary to not only perform with proficiency on local state and national assessments but also to provide our students with opportunities to develop confidence and competence as learners of mathematics through meaningful challenging and worthwhile activities. As such many teachers have turned to technology and cooperative groups as staples in the classroom. The purpose of this study was to understand how one first-year teacher implemented what she was taught in her undergraduate coursework in teaching two specific units of instruction in two sections of high …


Organic Sensitizers For High Efficiency Dye-Sensitized Solar Cells, Adithya Peddapuram Jan 2019

Organic Sensitizers For High Efficiency Dye-Sensitized Solar Cells, Adithya Peddapuram

Electronic Theses and Dissertations

After the industrial revolution in 19th-century energy, demand has increased exponentially. Relying on fossil fuels long term is not a good option due to their non-renewable nature and concerns about burning fossil fuels raising carbon dioxide levels in atmosphere. This dissertation describes, utilizing sunlight for electricity production with dye-sensitized solar cells (DSCs). DSCs are an attractive solar technology due to processing advantages over traditional solar cells. To improve the stability of DSCs, strong surface binding dyes are important. This work studies the dual anchor dual donor (DD-π-AA) dye framework with various donors (electron rich π-systems) and π-bridges (electron neutral π-systems). …


Near-Infrared High Efficiency Organic Dye Sensitized Solar Cells (Dscs) And Biological Fluorescent Imaging Dyes, Yanbing Zhang Jan 2019

Near-Infrared High Efficiency Organic Dye Sensitized Solar Cells (Dscs) And Biological Fluorescent Imaging Dyes, Yanbing Zhang

Electronic Theses and Dissertations

With the energy consumption increase every year, the non-renewable energy sources such as fossil fuels, natural gas, and coal will not sustain forever. In this case, searching for a way to develop a renewable energy source is an emergency. For decades, dye-sensitized solar cells (DSCs) have received intensive attention due to their high power conversion efficiency and low material cost. This dissertation describes efforts to design and synthesize near-infrared organic dyes to apply to two systems: first, for use in the improvement of DSCs by the optimization of electron rich components such as ullazine and cross-conjugated -bridges to increase photon-to-electricity …


Structural Controls And Depositional Environments Of The Glen Rose Subgroup In Pelahatchie Field In Rankin County, Mississippi, Chesney Petkovsek Jan 2019

Structural Controls And Depositional Environments Of The Glen Rose Subgroup In Pelahatchie Field In Rankin County, Mississippi, Chesney Petkovsek

Electronic Theses and Dissertations

Following Lion Oil’s drilling of the Sowell #1, Lower Cretaceous step-out drilling in Pelahatchie Field has led to the establishment of Mooringsport, Paluxy, Rodessa, Sligo, and Hosston oil and gas condensate production along the flanks and crest of a salt feature within Rankin County, Mississippi. Exploration of salt features has been intermittent throughout Mississippi, but has shifted from targeting pay zones along the crests of domal and piercement salt features in the 1940s, to targeting reserves along the flanks of these features in the 1970s. The dominant structural feature in Pelahatchie Field is an elongate north-south-trending salt ridge. Results of …


A Study To Regioselectively Access Fluorinated Triazoles And Isoxazoles, Sweta Adhikari Jan 2019

A Study To Regioselectively Access Fluorinated Triazoles And Isoxazoles, Sweta Adhikari

Electronic Theses and Dissertations

The objective of the thesis is to develop regioselective methods for mono-fluorination of disubstituted triazoles, both 1,4- and 1,5-regioisomer, and isoxazoles. These strategies focus on one-pot direct access to final mono-fluorinated triazoles and isoxazoles. Eventually, these fluorinated substrates will be screened against various biological targets. Similarly, the optimization study of a regioselective method to generate 5-fluoro-1,4-disubstituted triazole was conducted. This reaction also utilized 1,3-dipolar cycloaddition to synthesize fluorinated triazole. However, difluoroalkene was used as a synthetic equivalent of fluoroalkyne for this method. This resulted into the inversion of polarity affording a different regioisomer. Here, fluoronitroalkene was identified as a synthetic …


The Effects Of Hypoxia And Freshwater Intrusion On The Eastern Oyster (Crassostrea Virginica), James Henry Gledhill Jan 2019

The Effects Of Hypoxia And Freshwater Intrusion On The Eastern Oyster (Crassostrea Virginica), James Henry Gledhill

Electronic Theses and Dissertations

Recent estimates revealed a significant decrease in oyster populations worldwide. This drastic decrease has detrimental effects on coastal and estuarine ecosystems. Two environmental stressors that are thought to be contributing to the oyster population decline are hypoxia and excess freshwater intrusion. In this study, effects of hypoxia and low salinity on oysters were investigated using a combination of laboratory and field-based methods. In the laboratory, oysters were exposed to 2, 4, or 8 days of hypoxia (< 2 mg/L dissolved oxygen) folloby 6 days of recovery in normoxic conditions. At the same time, caged oysters were exposed to a naturally occurring hypoxic event in the field. After 8 days, laboratory-exposed oysters shoevidence of immunosuppression indicated by significant downregulation of the immune-related gene thymosin-β4 (Tβ-4) and a significant decrease in total circulating hemocytes compared to controls. However, in field oysters exposed to a naturally occurring hypoxic event, no effect on total hemocyte counts and an upregulation of Tβ-4 was observed. In a second field study, to investigate how oysters respond to prolonged freshwater exposure, caged oysters were placed on 23 April 2019 at six reef sites in the Mississippi Sound along with in situ water quality sensors. One-hundred percent mortality of caged oysters occurred at four of the six sites. Of the 6 six sites, Henderson Point Reef and Kittiwake Reef shosome caged oyster survival. At Henderson Point, where higher mortality was observed compared to Kittiwake, a significant increase in lipid peroxidation was detected. Analysis of mRNA expression of surviving caged and native oysters revealed downregulation of genes involved in immune function, low oxygen response, and osmoregulation. These results show possible evidence of energetic depression which inhibits adequate adaptation to low salinity conditions. Energetic depression and increased oxidative damage could have contributed to higher oyster mortality. Dredge sampling of native oysters at the all Mississippi Sound field sites on 27 September 2019, following recovery to ~15 ppt salinity, still indicated 100% native oyster mortality due to the prior prolonged freshwater exposure. Continued monitoring of western Mississippi Sound oyster reefs is crucial to observe recovery of oyster populations.


Optimizing The Performance Of Complex Engineering Systems Aided By Artificial Neural Networks, Khalil Qatu Jan 2019

Optimizing The Performance Of Complex Engineering Systems Aided By Artificial Neural Networks, Khalil Qatu

Electronic Theses and Dissertations

In the first problem Polyetherimide graphene nanoplatelets papers (PEIGNP) were tested with different graphene loadings varying from 0-97 weight percent (WT%). The resulting stress-strain curves were utilized to develop two ANN models. Stress-controlled and strain-controlled models. Both models shoan excellent correlation to the experimental. Several Mechanical properties were calculated from the predicted stress-strain curves namely; toughness maximum strength maximum strain and maximum tangent modulus. Both models captured the same overall behavior of the PEIGNP composite. However the strain-controlled model was found to predict lower stress than the stress-controlled model. Finally a Graphical User Interface (GUI) was developed to aid in …


The Schrödinger Equation With Coulomb Potential Admits No Exact Solutions, Ilia Toli Jan 2019

The Schrödinger Equation With Coulomb Potential Admits No Exact Solutions, Ilia Toli

Electronic Theses and Dissertations

We prove that the Schrödinger equation with the electrostatic potential energy expressed by the Coulomb potential does not admit exact solutions for three or more bodies. It follows that the exact solutions proposed by Fock [1–3] are flawed. The Coulomb potential is the problem. Based on the classical (non-quantum) principle of superposition, the Coulomb potential of a system of many particles is assumed to be the sum of all the pairwise Coulomb potentials. We prove that this is not accurate. The Coulomb potential being a hyperbolic (not linear) function, the superposition principle does not apply. The Schrödinger equation as studied …


Multi-Modal Interfaces For Sensemaking Of Graph-Connected Datasets, Anthony Wehrer Jan 2019

Multi-Modal Interfaces For Sensemaking Of Graph-Connected Datasets, Anthony Wehrer

Electronic Theses and Dissertations

The visualization of hypothesized evolutionary processes is often shown through phylogenetic trees. Given evolutionary data presented in one of several widely accepted formats, software exists to render these data into a tree diagram. However, software packages commonly in use by biologists today often do not provide means to dynamically adjust and customize these diagrams for studying new hypothetical relationships, and for illustration and publication purposes. Even where these options are available, there can be a lack of intuitiveness and ease-of-use. The goal of our research is, thus, to investigate more natural and effective means of sensemaking of the data with …


Security Analysis Of The Internet Of Things Using Digital Forensic And Penetration Testing Tools, Olajide Ojagbule Jan 2019

Security Analysis Of The Internet Of Things Using Digital Forensic And Penetration Testing Tools, Olajide Ojagbule

Electronic Theses and Dissertations

We exist in a universe where everything is related to the internet or each other like smart TVs, smart telephones, smart thermostat, cars and more. Internet of Things has become one of the most talked about technologies across the world and its applications range from the control of home appliances in a smart home to the control of machines on the production floor of an industry that requires less human intervention in performing basic daily tasks. Internet of Things has rapidly developed without adequate attention given to the security and privacy goals involved in its design and implementation. This document …


Conflict Free Connectivity And The Conflict-Free-Connection Number Of Graphs, Travis D. Wehmeier Jan 2019

Conflict Free Connectivity And The Conflict-Free-Connection Number Of Graphs, Travis D. Wehmeier

Electronic Theses and Dissertations

We explore a relatively new concept in edge-colored graphs called conflict-free connectivity. A conflict-free path is a (edge-) colored path that has an edge with a color that appears only once. Conflict-free connectivity is the maximal number of internally disjoint conflict-free paths between all pairs of vertices in a graph. We also define the c-conflict-free-connection of a graph G. This is the maximum conflict-free connectivity of G over all c-colorings of the edges of G. In this paper we will briefly survey the works related to conflict-free connectivity. In addition, we will use the probabilistic method to achieve a bound …


Totally Acyclic Complexes, Holly M. Zolt Jan 2019

Totally Acyclic Complexes, Holly M. Zolt

Electronic Theses and Dissertations

We consider the following question: when is every exact complex of injective modules a totally acyclic one? It is known, for example, that over a commutative Noetherian ring of finite Krull dimension this condition is equivalent with the ring being Iwanaga-Gorenstein. We give equivalent characterizations of the condition that every exact complex of injective modules (over arbitrary rings) is totally acyclic. We also give a dual result giving equivalent characterizations of the condition that every exact complex of flat modules is F-totally acyclic over an arbitrary ring.


Ifocus: A Framework For Non-Intrusive Assessment Of Student Attention Level In Classrooms, Narayanan Veliyath Jan 2019

Ifocus: A Framework For Non-Intrusive Assessment Of Student Attention Level In Classrooms, Narayanan Veliyath

Electronic Theses and Dissertations

The process of learning is not merely determined by what the instructor teaches, but also by how the student receives that information. An attentive student will naturally be more open to obtaining knowledge than a bored or frustrated student. In recent years, tools such as skin temperature measurements and body posture calculations have been developed for the purpose of determining a student's affect, or emotional state of mind. However, measuring eye-gaze data is particularly noteworthy in that it can collect measurements non-intrusively, while also being relatively simple to set up and use. This paper details how data obtained from such …