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Articles 1 - 30 of 1529

Full-Text Articles in Physical Sciences and Mathematics

Bots, Bias And Big Data: Artificial Intelligence, Algorithmic Bias And Disparate Impact Liability In Hiring Practices, Mckenzie Raub Dec 2018

Bots, Bias And Big Data: Artificial Intelligence, Algorithmic Bias And Disparate Impact Liability In Hiring Practices, Mckenzie Raub

Arkansas Law Review

No abstract provided.


Green Supply Chain Management: A Perspective On Best Practices In Gscm Design, Leroy Paddock, Natasha Rao Dec 2018

Green Supply Chain Management: A Perspective On Best Practices In Gscm Design, Leroy Paddock, Natasha Rao

Arkansas Law Review

No abstract provided.


Reclaiming Energy Efficiency In An Age Of Petroleum Exclusion, Monika Ehrman Dec 2018

Reclaiming Energy Efficiency In An Age Of Petroleum Exclusion, Monika Ehrman

Arkansas Law Review

No abstract provided.


Contracting For Sustainable Surface Management, Tara Righetti Dec 2018

Contracting For Sustainable Surface Management, Tara Righetti

Arkansas Law Review

No abstract provided.


Keynote: Motivating Private Climate Governance: The Role Of The Efficiency Gap, Michael P. Vandenbergh Dec 2018

Keynote: Motivating Private Climate Governance: The Role Of The Efficiency Gap, Michael P. Vandenbergh

Arkansas Law Review

The topic of this symposium, “Environmental Sustainability and Private Governance,” is important and timely. In response to the shrinking federal role in environmental protection, many policy advocates have focused on the role of states and cities, but this symposium focuses on another important source of sustainability initiatives: the private sector, including corporations, households, civic and cultural organizations, religious organizations, private hospitals, colleges and universities, and other organizations. States, cities, and other subnational government responses are increasingly important, but the limited geographic reach of subnational governments constrains their ability to address many environmental problems. For instance, although twenty states have set ...


The Role Of Information Communication Technologies (Icts) In Shaping Identity Threats And Responses, Mary Macharia Dec 2018

The Role Of Information Communication Technologies (Icts) In Shaping Identity Threats And Responses, Mary Macharia

Theses and Dissertations

With the rising use of social media, people are increasingly experiencing, and responding to, identity threats online. This sometimes leads to online backlash via “cybermobs” or the creation of online social movements that traverse offline. Prior information systems (IS) research on identity threats and responses largely focuses on information communication technology (ICT) implementations within organizations in an offline context. Therefore, we lack understanding of ICT-mediated identity threats and responses and ways to promote healthier and productive interactions online. This two-essay dissertation seeks to fill this gap. Essay 1 combines a review of ICT-mediated identity threats with a qualitative study (based ...


Sequential Inference For Hidden Markov Models, Michael Ellis Dec 2018

Sequential Inference For Hidden Markov Models, Michael Ellis

Theses and Dissertations

In many applications data are collected sequentially in time with very short time intervals between observations. If one is interested in using new observations as they arrive in time then non-sequential Bayesian inference methods, such as Markov Chain Monte Carlo (MCMC) sampling, can be too slow. Increasingly, state space models are being used to model nonlinear and non-Gaussian systems. The structure of state space models allows for sequential Bayesian inference so that an approximation to the posterior distribution of interest can be updated as new observations arrive. In special cases, the exact posterior distribution can be updated through conjugate Bayesian ...


Subsurface Analysis Of Mississippian Tripolitic Chert In Northwest Arkansas, Thomas Jason Liner Dec 2018

Subsurface Analysis Of Mississippian Tripolitic Chert In Northwest Arkansas, Thomas Jason Liner

Theses and Dissertations

Over the past 70 years the Mississippian strata of Northwest Arkansas have been studied in great detail. The study area is located on the escarpment between the Boston Mountains Plateau and the Springfield Plateau where a surface occurrence of Mississippian age rock allows for access to outcrops in close proximity to gas wells that encounter subsurface Mississippian strata. Many outcrops found in Northwest Arkansas expose Lower Mississippian (Kinderhookian-Osagean) strata that represent a full third order transgressive/regressive sequence that is unconformity bounded. These Mississippian outcrops are commonly treated as surface analogs to the Mississippi Lime Play in North Central Oklahoma ...


Molecular Dynamics Investigation Of The Thermodynamics Of Nanoscale Droplets And Kinetics Of Weakly Correlated Systems, Kai Yang Leong Dec 2018

Molecular Dynamics Investigation Of The Thermodynamics Of Nanoscale Droplets And Kinetics Of Weakly Correlated Systems, Kai Yang Leong

Theses and Dissertations

The surface tension of nanoscale droplets of water was studied with molecular dynamics simulations using the BLYPSP-4F water potential. The internal pressure of the droplet was measured using a correlation between the pressure and density, established through a series of bulk simulations performed at pressures from 1 to 1000 bar. Such a procedure allows for reliable determination of internal pressure without the need to calculate the local Virial. The surface tension, estimated with the Young-Laplace relation, shows a good agreement with the Tolman equation with a Tolman length of -0.48 Å. The interface of a liquid water droplet is ...


Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham Dec 2018

Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham

Theses and Dissertations

The Arkoma Basin is a Carboniferous peripheral foreland basin creating a structural depression covering an approximate area of 33,800 miles2 that extends through east-central Oklahoma and west-central Arkansas. The entire basin fill includes Pre-Mississippian carbonate shelf deposits, Mississippian marine carbonates and black shales, and Pennsylvanian mixed carbonated/clastic and shore zone/deltaic deposits. The Lower Atoka formation (Pennsylvanian) occurs in outcrop along the southern Boston Mountain Plateau in northern Arkansas and extends into the subsurface of the Arkoma Basin over an area of 2,300 miles2. The Lower Atoka ranges from 600 to 1500 feet in thickness and represents ...


An Integrated Well Log And 3d Seismic Interpretation Of Missourian Clinoforms, Osage County, Oklahoma, Abram Max Barker Dec 2018

An Integrated Well Log And 3d Seismic Interpretation Of Missourian Clinoforms, Osage County, Oklahoma, Abram Max Barker

Theses and Dissertations

Integrated analysis of well and geophysical data can provide detailed geologic interpretation of the subsurface in Osage County, Oklahoma. Systems tracts and depositional system successions can be interpreted at marginal seismic resolution using well log motif with seismic reflector character within a depositional context. Shelf-prism and subaqueous, delta-scale clinoforms of Missourian age observed in 3D seismic were interpreted with greater sequence stratigraphic detail when coupled with wireline well logs. The Late Pennsylvanian Midcontinent Sea was thought to be approximately 150 feet average depth across the southern Midcontinent during the Missourian Stage, and deepen towards the Arkoma and Anadarko Basins to ...


Budget-Constrained Regression Model Selection Using Mixed Integer Nonlinear Programming, Jingying Zhang Dec 2018

Budget-Constrained Regression Model Selection Using Mixed Integer Nonlinear Programming, Jingying Zhang

Theses and Dissertations

Regression analysis fits predictive models to data on a response variable and corresponding values for a set of explanatory variables. Often data on the explanatory variables come at a cost from commercial databases, so the available budget may limit which ones are used in the final model.

In this dissertation, two budget-constrained regression models are proposed for continuous and categorical variables respectively using Mixed Integer Nonlinear Programming (MINLP) to choose the explanatory variables to be included in solutions. First, we propose a budget-constrained linear regression model for continuous response variables. Properties such as solvability and global optimality of the proposed ...


Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern Dec 2018

Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern

Biological Sciences Undergraduate Honors Theses

Methanogens, some of Earth’s most primitive prokaryotic organisms, are candidates for possible life forms capable of inhabiting Mars. Specifically, four different species (Methanobacterium formicicum, Methanococcus maripaludis, Methanosarcina barkeri, Methanothermobacter wolfeii) were analyzed for their tolerance to the presence of illite clay. Illite is a crystalline mineral that has been identified from regions of Mars’s surface. Results indicated that all four species grew with some success in the illite at different concentrations. This experimentation with methanogens’ abilities to survive and reproduce in the presence of illite allows for a more accurate understanding of the potential capability of microbial growth ...


Learning-Based Analysis On The Exploitability Of Security Vulnerabilities, Adam Bliss Dec 2018

Learning-Based Analysis On The Exploitability Of Security Vulnerabilities, Adam Bliss

Computer Science and Computer Engineering Undergraduate Honors Theses

The purpose of this thesis is to develop a tool that uses machine learning techniques to make predictions about whether or not a given vulnerability will be exploited. Such a tool could help organizations such as electric utilities to prioritize their security patching operations. Three different models, based on a deep neural network, a random forest, and a support vector machine respectively, are designed and implemented. Training data for these models is compiled from a variety of sources, including the National Vulnerability Database published by NIST and the Exploit Database published by Offensive Security. Extensive experiments are conducted, including testing ...


Synthesis Of Dicamba Glucosides For The Study Of Environmental Dicamba Drift Effects On Soybeans, Holly Wallace Dec 2018

Synthesis Of Dicamba Glucosides For The Study Of Environmental Dicamba Drift Effects On Soybeans, Holly Wallace

Theses and Dissertations

The most popular herbicide used for weed control has been glyphosate for many years in the Midwestern United States. Plants have begun to develop a resistance to glyphosate due to over use of the herbicide. This herbicide resistance has pushed farmers to turn to alternative herbicides such as dicamba and 2,4-D. Recently agrochemical companies have developed genetically modified crops that are resistant to herbicides such as dicamba. These modified crops allow farmers to spray their fields with dicamba without fear of crop damage. Farmers of non-genetically modified crops, however, suffer damage and loss of yield from herbicide drift effects ...


Managing Lake Fertility Within The Guidelines Of A Nutrient Management Plan And Based On Algal Nutrient Limitation, Bradley J. Austin, J. Thad Scott, Brian E. Haggard Nov 2018

Managing Lake Fertility Within The Guidelines Of A Nutrient Management Plan And Based On Algal Nutrient Limitation, Bradley J. Austin, J. Thad Scott, Brian E. Haggard

Technical Reports

The specific objectives were to first, monitor nutrients, algal biomass, and water clarity in lakes Cove, Spring, and Wedington. Second, evaluate whether algal growth in each of the lakes was limited by N, P, or both N and P. This research was conducted to help USFS better manage lake fertilization to maximize algal growth and improve the fisheries within these lakes.


Interpolating Between Multiplicities And F-Thresholds, William D. Taylor Aug 2018

Interpolating Between Multiplicities And F-Thresholds, William D. Taylor

Theses and Dissertations

We define a family of functions, called s-multiplicity for each s>0, that interpolates between Hilbert-Samuel multiplicity and Hilbert-Kunz multiplicity by comparing powers of ideals to the Frobenius powers of ideals. The function is continuous in s, and its value is equal to Hilbert-Samuel multiplicity for small values of s and is equal to Hilbert-Kunz multiplicity for large values of s. We prove that it has an associativity formula generalizing the associativity formulas for Hilbert-Samuel and Hilbert-Kunz multiplicity. We also define a family of closures, called s-closures, such that if two ideals have the same s-closure then they have the ...


Geophysical Assessment Of Subsurface Soil Conditions Using Capacitively Coupled Resistivity, Folaseye Coker Aug 2018

Geophysical Assessment Of Subsurface Soil Conditions Using Capacitively Coupled Resistivity, Folaseye Coker

Theses and Dissertations

The purpose of this research is to explore the applicability of Capacitively-Coupled Resistivity (CCR) as an improvement on traditional drilling and sampling methods for subsurface soil investigations. The CCR method could be used to identify critical locations for drilling and sampling such as expansive clay layers and anomalies (sinkholes, unknown landfills, etc.) rather than uniformly sampling across a site. CCR surveys were performed at Alpena, Arkansas along a highway expansion project changing US 62 from a two lane to four lane highway, and at Alton, Illinois along the Mel Price Levee, a 5.2 mile levee along a portion of ...


Comparison Of Correlation, Partial Correlation, And Conditional Mutual Information For Interaction Effects Screening In Generalized Linear Models, Ji Li Aug 2018

Comparison Of Correlation, Partial Correlation, And Conditional Mutual Information For Interaction Effects Screening In Generalized Linear Models, Ji Li

Theses and Dissertations

Numerous screening techniques have been developed in recent years for genome-wide association studies (GWASs) (Moore et al., 2010). In this thesis, a novel model-free screening method was developed and validated by an extensive simulation study. Many screening methods were mainly focused on main effects, while very few studies considered the models containing both main effects and interaction effects. In this work, the interaction effects were fully considered and three different methods (Pearson’s Correlation Coefficient, Partial Correlation, and Conditional Mutual Information) were tested and their prediction accuracies were compared.

Pearson’s Correlation Coefficient method, which is a direct interaction screening ...


Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd Aug 2018

Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd

Theses and Dissertations

The natural flow regime exerts primacy over lotic ecosystem patterns and processes. However, little work has examined the influence of flow regime on instream and riparian carbon (C) dynamics in minimally-impacted, temperate forested systems. To date, most research efforts have focused on characterizing C movement and transformations across biomes and land use categories; however, flow regime represents an overlooked, finer level of detail that may drive differences in ecosystem function. My dissertation objective was to measure C fixation and movement within and across multiple environmental spheres (e.g. within stream channels, between stream surfaces and the atmosphere, and from riparian ...


Privacy-Preserving Photo Taking And Accessing For Mobile Phones, Ang Li Aug 2018

Privacy-Preserving Photo Taking And Accessing For Mobile Phones, Ang Li

Theses and Dissertations

Today, we are living in environments that are full of cameras embedded in devices such as smart phones and wearables. These mobile devices and as well as apps installed on them are designed to be extremely convenient for users to take, store and share photos. In spite of the convenience brought by ubiquitous cameras, users' privacy may be breached through photos that are taken and stored with mobile devices. For example, when users take a photo of a scenery, a building or a target person, a stranger may also be unintentionally captured in the photo. Such photos expose the location ...


Theatrical Genre Prediction Using Social Network Metrics, Manisha Shukla Aug 2018

Theatrical Genre Prediction Using Social Network Metrics, Manisha Shukla

Theses and Dissertations

With the emergence of digitization, large text corpora are now available online that provide humanities scholars an opportunity to perform literary analysis leveraging the use of computational techniques. This work is focused on applying network theory concepts in the field of literature to explore correlations between the mathematical properties of the social networks of plays and the plays’ dramatic genre, specifically how well social network metrics can identify genre without taking vocabulary into consideration. Almost no work has been done to study the ability of mathematical properties of network graphs to predict literary features. We generated character interaction networks of ...


Sustainability Of Utilizing Renewable And Nuclear Energy In Saudi Arabia Using Different Types Of Life Cycle Assessment, Kamel Almutairi Aug 2018

Sustainability Of Utilizing Renewable And Nuclear Energy In Saudi Arabia Using Different Types Of Life Cycle Assessment, Kamel Almutairi

Theses and Dissertations

Evaluating the global environmental impacts of the current and future energy policies in Saudi Arabia using Life cycle assessment (LCA) method was the main objective of this dissertation. First, the attributional life cycle assessment (ALCA) framework was used to evaluate the Saudi’s air conditioning systems, as they are responsible for about 70% of the total Saudi residential electricity consumption. The ALCA’s results showed that the AC use phase produces the largest share of the environmental impact and the magnitude of the environmental impacts is influenced by the type of primary fuel used for electricity generation.

Emerging non-fossil sources ...


Stratigraphic Evaluation Of The St. Joe-Boone Boundary Interval, Kinderhookian-Osagean Series, Lower Mississippian System, Tri-State Region, Southern Midcontinent, Forrest Dalton Mcfarlin Aug 2018

Stratigraphic Evaluation Of The St. Joe-Boone Boundary Interval, Kinderhookian-Osagean Series, Lower Mississippian System, Tri-State Region, Southern Midcontinent, Forrest Dalton Mcfarlin

Theses and Dissertations

The Lower Mississippian interval comprises a single, third-order, eustatic cycle subdivided lithostratigraphically into the St. Joe Limestone (Hopkins 1893) and overlying Boone Formation (Branner 1891, Simonds 1891) with type areas in northern Arkansas. Coeval, homotaxial limestones occur in adjacent southwestern Missouri and northeastern Oklahoma. Missouri formation names for the St. Joe interval are recognized in Arkansas as members (ascending order): Bachelor, Compton, Northview, Pierson. The Boone interval in Missouri is represented by the (ascending order): Reeds Spring, Elsey, Burlington-Keokuk undifferentiated, but utilization of those names in Arkansas is problematic. in northern Arkansas, the Boone Formation is subdivided into informal lower ...


Methane Emissions From Rice Production On A Silt-Loam Soil In Arkansas, Joshua Jeffry Humphreys Aug 2018

Methane Emissions From Rice Production On A Silt-Loam Soil In Arkansas, Joshua Jeffry Humphreys

Theses and Dissertations

Methane (CH4) emissions from rice (Oryza sativa L.) production are a source of concern in the environmental and agricultural communities. New and/or revised agronomic methodologies will be needed to identify production practice combinations that reduce CH4 emissions without decreasing yields. The objective of this multi-year study was to evaluate the effects of water management (i.e., full-season flood and mid-season drain) (2015), cultivar (i.e., pure-line cultivar ‘LaKast’ and the RiceTec hybrid “XP753”) (2015), soil organic matter (SOM) concentration (2016), and tillage [conventional tillage (CT) and no-tillage (NT)] and urea-based fertilizers [N-(n-butyl) thiophosphoric triamide (NBPT)-coated urea and ...


Mapping Lower Austin Chalk Secondary Porosity Using Modern 3-D Seismic And Well Log Methods In Zavala County, Texas, David Kilcoyne Aug 2018

Mapping Lower Austin Chalk Secondary Porosity Using Modern 3-D Seismic And Well Log Methods In Zavala County, Texas, David Kilcoyne

Theses and Dissertations

Establishing fracture distribution and porosity trends is key to successful well design in a majority of unconventional plays. The Austin Chalk has historically been referred to as an unpredictable producer due to high fracture concentration and lateral variation in stratigraphy, however recent drilling activity targeting the lower Austin Chalk has been very successful. The Upper Cretaceous Austin Chalk (AC) and underlying Eagle Ford (EF) units are considered by many to act as a single hydrocarbon system, with communication between these two units largely through expulsion or dewatering fractures, extensional faults or along the AC/EF unconformity. Total porosity for the ...


Chemical Strategies For Drug Development Of Fucose-Truncated Ipomoeassin F Analogues, Melissa Hirsch Aug 2018

Chemical Strategies For Drug Development Of Fucose-Truncated Ipomoeassin F Analogues, Melissa Hirsch

Theses and Dissertations

Natural product synthesis has many applications in the field of chemical biology, due to the protein binding affinity to the complex three-dimensional structure. However, synthetic and structure-activity relationship studies concerning certain drug targets are scarce. For example, members of the ipomoeassin family have exhibited anti-cancer properties, but cost-effective optimization of these compounds has not yet been extensively studied. Ipomoeassin F, a natural glycoresin isolated from the leaves of the Ipomoea squamosa plant in the Suriname rainforest, has shown high cytotoxicity, with IC50 values measured at the low nanomolar range. Two studies by Postema and Fuerstner have outlined synthesis pathways for ...


Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam Aug 2018

Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam

Theses and Dissertations

Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable ...


Comparative Microbial Community Dynamics In A Karst Aquifer System And Proximal Surface Stream In Northwest Arkansas, Josue Rodriguez Aug 2018

Comparative Microbial Community Dynamics In A Karst Aquifer System And Proximal Surface Stream In Northwest Arkansas, Josue Rodriguez

Theses and Dissertations

Northwest Arkansas has well-developed karst systems, with numerous sinking streams and springs. Karst conduits make it easy for contaminants to enter groundwater systems, degrading the water quality and destroying fragile karst ecosystems. With the increase of urbanization, potential threats in the form of fecal contamination may prove to be more of a problem. The purpose of this research is to compare the difference between microbial communities within two different settings, a karst aquifer and a surface stream. The microbial communities within Blowing Spring Cave and Little Sugar Creek were detected and identified in water and sediment samples. Samples were also ...


Conformationally-Controlled Late-Stage Modifications For Sar Studies Of The C-3-Glcp Moiety Of Ipomoeassin F, Lucas Whisenhunt Aug 2018

Conformationally-Controlled Late-Stage Modifications For Sar Studies Of The C-3-Glcp Moiety Of Ipomoeassin F, Lucas Whisenhunt

Theses and Dissertations

The resin glycoside, ipomoeassin F has been shown to be extremely potent against multiple cancer lines (IC50 = 4.2-36 nM). However, the mechanism of action of this potent and complex natural product is still not fully understood. The α,β-unsaturated esters of the glucosyl moiety have been shown to be vital for the overall cytotoxicity of ipomoeassin F. Nevertheless, the importance of the tigloyl ester of the glucosyl moiety is still largely unknown. This work aimed to study the pharmacophore importance of the tigloyl ester by creating, an efficient, scalable, and flexible synthesis route for various analogs. The 18-linear step ...