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Revolution In Crime: How Cryptocurrencies Have Changed The Criminal Landscape, Igor Groysman 2018 City University of New York (CUNY)

Revolution In Crime: How Cryptocurrencies Have Changed The Criminal Landscape, Igor Groysman

Student Theses

This thesis will examine the ways in which various cryptocurrencies have impacted certain traditional crimes. While crime is always evolving with technology, cryptocurrencies are a game changer in that they provide anonymous and decentralized payment systems which, while they can be tracked in a reactive sense via the blockchain, are seen by criminals as having better uses for them than traditional fiat currencies, such as the ability to send money relatively fast to another party without going through an intermediary, or the ability to obscure the origin of the money for money laundering purposes. Every week there are new cryptocurrencies ...


Performance Assessment Of The Extended Gower Coefficient On Mixed Data With Varying Types Of Functional Data., Obed Koomson 2018 East Tennessee State University

Performance Assessment Of The Extended Gower Coefficient On Mixed Data With Varying Types Of Functional Data., Obed Koomson

Electronic Theses and Dissertations

Clustering is a widely used technique in data mining applications to source, manage, analyze and extract vital information from large amounts of data. Most clustering procedures are limited in their performance when it comes to data with mixed attributes. In recent times, mixed data have evolved to include directional and functional data. In this study, we will give an introduction to clustering with an eye towards the application of the extended Gower coefficient by Hendrickson (2014). We will conduct a simulation study to assess the performance of this coefficient on mixed data whose functional component has strictly-decreasing signal curves and ...


Sequential Inference For Hidden Markov Models, Michael Ellis 2018 University of Arkansas, Fayetteville

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 2018 University of Arkansas, Fayetteville

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 2018 University of Arkansas, Fayetteville

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 ...


The Advanced Mesospheric Temperature Mapper: Remote Sensing Of The Nighttime Oh Layer During The Deepwave Campaign, Pattilyn McLaughlin 2018 Utah State University - Center for Atmospheric and Space Sciences

The Advanced Mesospheric Temperature Mapper: Remote Sensing Of The Nighttime Oh Layer During The Deepwave Campaign, Pattilyn Mclaughlin

All Graduate Plan B and other Reports

The Advanced Mesospheric Temperature Mapper [AMTM] is a remote sensing instrument developed at Utah State University to map temperature structures in the hydroxyl airglow emission at ~87 km. These maps can then be used to quantify wave field characteristics and to observe general climatology trends. Two recent campaigns that it has been involved with are the DEEPWAVE campaign in Lauder, New Zealand and the Super Soaker campaign in Fairbanks, Alaska.

The Deep Propagating Gravity Wave Experiment, “DEEPWAVE” was an international measurement and modeling program intended to characterize the generation and propagation of a broad range of atmospheric gravity waves with ...


Rfviz: An Interactive Visualization Package For Random Forests In R, Christopher Beckett 2018 Utah State University

Rfviz: An Interactive Visualization Package For Random Forests In R, Christopher Beckett

All Graduate Plan B and other Reports

Random forests are very popular tools for predictive analysis and data science. They work for both classification (where there is a categorical response variable) and regression (where the response is continuous). Random forests provide proximities, and both local and global measures of variable importance. However, these quantities require special tools to be effectively used to interpret the forest. Rfviz is a sophisticated interactive visualization package and toolkit in R, specially designed for interpreting the results of a random forest in a user-friendly way. Rfviz uses a recently developed R package (loon) from the Comprehensive R Archive Network (CRAN) to create ...


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

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 2018 University of Arkansas, Fayetteville

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 2018 University of Arkansas, Fayetteville

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 2018 University of Arkansas, Fayetteville

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 ...


Associated Dataset: Ocean Circulation Causes Strong Variability In The Mid-Atlantic Bight Nitrogen Budget, Marjorie A.M. Friedrichs, Pierre St-Laurent 2018 Virginia Institute of Marine Science

Associated Dataset: Ocean Circulation Causes Strong Variability In The Mid-Atlantic Bight Nitrogen Budget, Marjorie A.M. Friedrichs, Pierre St-Laurent

Data

The dataset includes model outputs used in the associated publication (Friedrichs et al.), which used the United States Eastern Continental Shelf (USECoS) biogeochemical model embedded in the Regional-Ocean-Modeling-System (ROMS) to examine the impact of the oceanic circulation on the nitrogen budget of the Mid-Atlantic Bight (MAB). The model simulation covers the period 2004 to 2008 and is fully described in the associated publication. The model simulation highlights that the horizontal along-shelf and across-shelf fluxes dominate the spatiotemporal variability of net community production (NCP) in the MAB. The highest NCP is found in a year when inorganic nitrogen entering from across ...


Landscape Structure And Dynamics Of Recreational Fisheries, Christine N. Ruskamp 2018 University of Nebraska-Lincoln

Landscape Structure And Dynamics Of Recreational Fisheries, Christine N. Ruskamp

Dissertations & Theses in Natural Resources

Angler populations and the waterbodies they use are patchily distributed, creating putatively complex user-resource dynamics on the landscape. Spatially and temporally dynamic relationships between anglers and waterbodies can be difficult to track, understand, and manage. We often focus our efforts on the angler (directly or indirectly) with far less attention devoted to understanding the spatial structure and dynamics of fisheries on the landscape. Waterbodies serve as dynamic attractors on the landscape, shaping landscape patterns in angler participation. We surmise that by understanding the spatial structure and dynamics of recreational fisheries we can gain tremendous insight to cross-scale patterns that shape ...


Learning-Based Analysis On The Exploitability Of Security Vulnerabilities, Adam Bliss 2018 University of Arkansas, Fayetteville

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 ...


Spatial And Temporal Structure Of A Canid Community In Nebraska, Lucia Corral Hurtado 2018 University of Nebraska-Lincoln

Spatial And Temporal Structure Of A Canid Community In Nebraska, Lucia Corral Hurtado

Dissertations & Theses in Natural Resources

Understanding patterns of space-use by individuals, their distribution, and how they coexist with ecologically similar species is crucial to address various issues in ecology, evolution, conservation biology, and wildlife management. However, the study of such patterns challenging because the relationship among species and their environment is shaped by multiple ecological processes, many of which are acting at different scales, often in a hierarchical manner. In the Canidae family, for instance, where interference competition appears critical, larger species such as coyotes (Canis latrans), can often affect smaller species, such as red fox (Vulpes vulpes) and swift fox (Vulpes velox), by killing ...


Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy 2018 University of Nebraska-Lincoln

Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy

Dissertations & Theses in Natural Resources

Grasslands provide food, fiber, and numerous ecosystem services to human populations as well as habitat for wildlife. They are also some of the most endangered ecosystems in the world because of their productive soils and open topography. This problem is exacerbated by the accelerating conversion of grassland to cropland and encroaching trees and shrubs. The quality of remaining grasslands will be of increasing importance because of the biodiversity and vital ecosystem services they provide. Heterogeneity is a term specific to rangeland science that is illustrative of grassland health. Grassland species require very specific and differing habitats and without the variation ...


Synthesis, Characterization, And Catalytic Activity Of Copper Palladium Oxide Solid Solutions., Gregory L. Christensen 2018 University of Nebraska-Lincoln

Synthesis, Characterization, And Catalytic Activity Of Copper Palladium Oxide Solid Solutions., Gregory L. Christensen

Student Research Projects, Dissertations, and Theses - Chemistry Department

CuxPd1-xO forms a homogeneous solid solution over the wide range of 0 ≤ x ≤ 0.725 in which compositional variation can be correlated with structural and chemical environmental changes. After a small lag at low Cu2+ concentrations, where the lattice cell parameters are pinned to that of the pure PdO structure, CuxPd1-xO lattice parameters follow Vegard’s law in which the cell volume decreases linearly with x, indicating a homogenous solution in which Cu2+ randomly replaces the larger Pd2+ cation. The crystal structure also undergoes an increase in the c ...


Synthesis Of Dicamba Glucosides For The Study Of Environmental Dicamba Drift Effects On Soybeans, Holly Wallace 2018 University of Arkansas, Fayetteville

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 ...


Dreadd Targeting Projections From The Nucleus Accumbens To The Ventral Pallidum With Nicotine Self-Administration, Amanda Smith 2018 East Tennessee State University

Dreadd Targeting Projections From The Nucleus Accumbens To The Ventral Pallidum With Nicotine Self-Administration, Amanda Smith

Electronic Theses and Dissertations

Projections from the Nucleus Accumbens (NAc) to the Ventral Pallidum (VP) play a critical role in motivation and reward. Rewards and reward-associated cues are thought to alter this pathway by suppressing GABA release to the VP, however, the role of the NAc to VP pathway has never been investigated with regard to nicotine self-administration. We hypothesized that increasing GABAergic signaling from the NAc to the VP would decrease the reinforcing effects of nicotine. To increase GABA release, CRE dependent DREADD was expressed in the NAc of male rats. Administration of low dose clozapine activated the DREADD receptor and showed a ...


Imidacloprid Persistence, Mobility, And Effect On Ecosystem Function, Joanna Hardin 2018 East Tennessee State University

Imidacloprid Persistence, Mobility, And Effect On Ecosystem Function, Joanna Hardin

Electronic Theses and Dissertations

Imidacloprid is a neonicotinoid pesticide used to protect against biting and sucking insects. Land managers rely on its systemic properties, however long-term studies investigating imidacloprid effects on ecosystem function are limited. This study investigated imidacloprid applications to Tsuga caroliniana and Tsuga canadensis over time and compared concentrations to measures of ecosystem function including soil respiration, microbial function, and invertebrate density. Results indicate that imidacloprid is persistent (p0.5). Microbial function and invertebrate density were not significantly different between control and treatment locations nor did imidacloprid concentrations correlate with ecosystem functional indicator activity (p>0.05). It is evident that imidacloprid ...


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