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2019

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Full-Text Articles in Physical Sciences and Mathematics

Exploring Strategies For Implementing Information Security Training And Employee Compliance Practices, Alan Robert Dawson Jan 2019

Exploring Strategies For Implementing Information Security Training And Employee Compliance Practices, Alan Robert Dawson

Walden Dissertations and Doctoral Studies

Humans are the weakest link in any information security (IS) environment. Research has shown that humans account for more than half of all security incidents in organizations. The purpose of this qualitative case study was to explore the strategies IS managers use to provide training and awareness programs that improve compliance with organizational security policies and reduce the number of security incidents. The population for this study was IS security managers from 2 organizations in Western New York. Information theory and institutional isomorphism were the conceptual frameworks for this study. Data collection was performed using face-to-face interviews with IS managers …


Wellness Paradigms In Predicting Stress And Burnout Among Beginning Expatriate Teachers, Kimala Proctor Jan 2019

Wellness Paradigms In Predicting Stress And Burnout Among Beginning Expatriate Teachers, Kimala Proctor

Walden Dissertations and Doctoral Studies

Research indicates that the current teacher shortage is in part due to stress and burnout. A topic that has not been examined is beginning expatriate English medium teachers (EMTs) with 5 years or less of teaching experience in the United Arab Emirates and the relationship between using individualized, self-initiated wellness paradigms and stress, job burnout, and intent to leave the teaching profession. The transactional model of stress and coping, Maslach's multidimensional theory of burnout, and the health promotion model were used to evaluate the moderating effects of the EMTs' burnout and stress levels on their wellness and intent to leave. …


Optimizing Green Supply Chain Management Strategies, Mark Derek De La Grandiere Jan 2019

Optimizing Green Supply Chain Management Strategies, Mark Derek De La Grandiere

Walden Dissertations and Doctoral Studies

Some business leaders in the manufacturing industry lack strategies to optimize green supply chain management strategies that increase profitability while reducing the carbon footprint. The lack of green supply chain strategies sub optimizes the use of resources business leaders use to meet their financial goals. The purpose of this qualitative single case study was to explore successful green supply chain strategies leaders used to increase profitability while reducing the carbon footprint. The participants were 7 business leaders in one manufacturing organization headquartered in Massachusetts who have sophisticated green supply chain strategies in place. The natural resource-based view theory was the …


Strategies To Mitigate Supply Chain Disruptions In Grocery Businesses, Gift Wilford Bondwe Jan 2019

Strategies To Mitigate Supply Chain Disruptions In Grocery Businesses, Gift Wilford Bondwe

Walden Dissertations and Doctoral Studies

Supply chains have become more complex in the global economy, which has made supply chain disruptions inevitable. Disruptions can cause loss of profitability and hinder business growth. The goal of this multiple case study was to explore strategies to mitigate the effects of disruption in grocery store supply chains. The conceptual framework for this study was the resource dependency theory, which stipulates that firms rely on other businesses in the external environment for critical resources to create a competitive edge. Four purposively selected participants from 4 grocery store businesses in Northwest Arkansas participated in semistructured interviews and provided organizational documentation …


Employer Strategies For Improving Employee Work-Life Balance, Vernessa Lashawn Johnson-Hoffman Jan 2019

Employer Strategies For Improving Employee Work-Life Balance, Vernessa Lashawn Johnson-Hoffman

Walden Dissertations and Doctoral Studies

Senior leaders who fail to implement work-life balance strategies may experience reduced profits and sustainability challenges. This single case study explored employers' strategies for improving employee work-life balance. The population for the study included 4 senior leaders of a hospice care agency in North Carolina who successfully implemented employee work-life balance strategies. Data were collected from semistructured interviews and from the review of company documents, website, and social media pages. The conceptual framework for the study was the transformational leadership theory. The trustworthiness of interpretations was supported by member checking. Four themes emerged from inductive analysis of the data: a …


Strategies That Mitigate It Infrastructure Demands Produced By Student Byod Usa, Martha Dunne Jan 2019

Strategies That Mitigate It Infrastructure Demands Produced By Student Byod Usa, Martha Dunne

Walden Dissertations and Doctoral Studies

The use of bring your own devices (BYOD) is a global phenomenon, and nowhere is it more evident than on a college campus. The use of BYOD on academic campuses has grown and evolved through time. The purpose of this qualitative multiple case study was to identify the successful strategies used by chief information officers (CIOs) to mitigate information technology infrastructure demands produced by student BYOD usage. The diffusion of innovation model served as the conceptual framework. The population consisted of CIOs from community colleges within North Carolina. The data collection process included semistructured, in-depth face-to-face interviews with 9 CIOs …


Exploring Data Security Management Strategies For Preventing Data Breaches, Michael Samuel Ofori-Duodu Jan 2019

Exploring Data Security Management Strategies For Preventing Data Breaches, Michael Samuel Ofori-Duodu

Walden Dissertations and Doctoral Studies

Insider threat continues to pose a risk to organizations, and in some cases, the country at large. Data breach events continue to show the insider threat risk has not subsided. This qualitative case study sought to explore the data security management strategies used by database and system administrators to prevent data breaches by malicious insiders. The study population consisted of database administrators and system administrators from a government contracting agency in the northeastern region of the United States. The general systems theory, developed by Von Bertalanffy, was used as the conceptual framework for the research study. The data collection process …


Exploring Industry Cybersecurity Strategy In Protecting Critical Infrastructure, Mark Boutwell Jan 2019

Exploring Industry Cybersecurity Strategy In Protecting Critical Infrastructure, Mark Boutwell

Walden Dissertations and Doctoral Studies

Successful attacks on critical infrastructure have increased in occurrence and sophistication. Many cybersecurity strategies incorporate conventional best practices but often do not consider organizational circumstances and nonstandard critical infrastructure protection needs. The purpose of this qualitative multiple case study was to explore cybersecurity strategies used by information technology (IT) managers and compliance officers to mitigate cyber threats to critical infrastructure. The population for this study comprised IT managers and compliance officers of 4 case organizations in the Pacific Northwest United States. The routine activity theory developed by criminologist Cohen and Felson in 1979 was used as the conceptual framework. Data …


Cybersecurity Policy Development At The State Level: A Case Study Of Middle Tennessee, Daniel Leslie Scherr Jan 2019

Cybersecurity Policy Development At The State Level: A Case Study Of Middle Tennessee, Daniel Leslie Scherr

Walden Dissertations and Doctoral Studies

Cybersecurity is a growing threat not only to nations, critical infrastructure, and major entities, but also to smaller organizations and individuals. The growing number of successful attacks on all manner of U.S. targets highlights the need for effective and comprehensive policy from the local to federal level, though most research focuses on federal policy issues, not state issues. The purpose of this study was to examine the effectiveness of the decision-making process within the current cybersecurity policy environment in a southern state of the United States. Sabatier's advocacy coalition framework served as the theoretical framework for the study. Data were …


Managing Security Objectives For Effective Organizational Performance Information Security Management, Ramamohan Gutta Jan 2019

Managing Security Objectives For Effective Organizational Performance Information Security Management, Ramamohan Gutta

Walden Dissertations and Doctoral Studies

Information is a significant asset to organizations, and a data breach from a cyberattack harms reputations and may result in a massive financial loss. Many senior managers lack the competencies to implement an enterprise risk management system and align organizational resources such as people, processes, and technology to prevent cyberattacks on enterprise assets. The purpose of this Delphi study was to explore how the managerial competencies for information security and risk management senior managers help in managing security objectives and practices to mitigate security risks. The National Institute of Standards and Technology framework served as the foundation for this study. …


Cybersecurity Strategies To Protect Information Systems In Small Financial Institutions, Johnny Fadel Rawass Jan 2019

Cybersecurity Strategies To Protect Information Systems In Small Financial Institutions, Johnny Fadel Rawass

Walden Dissertations and Doctoral Studies

Leaders of financial institutions face challenges in protecting data because of the increased use of computer networks in the commerce and governance aspects of their businesses. The purpose of this single case study was to explore the strategies that leaders of a small financial institution used to protect information systems from cyber threats. The actor-network theory was the conceptual framework for this study. Data were collected through face-to-face, semistructured interviews with 5 leaders of a small financial institution in Qatar and a review of company documents relevant to information security, cybersecurity, and risk management. Using thematic analysis and Yin'€™s 5-€step …


Experimental Preservation Of Muscle Tissue In Quartz Sand And Kaolinite: Supplemental Information, Sharon A. Newman, Mirna Daye, Sirine C. Fakra, Matthew A. Marcus, Mihkel Pajusalu, Sara B. Pruss, Emily F. Smith, Tanja Bosak Jan 2019

Experimental Preservation Of Muscle Tissue In Quartz Sand And Kaolinite: Supplemental Information, Sharon A. Newman, Mirna Daye, Sirine C. Fakra, Matthew A. Marcus, Mihkel Pajusalu, Sara B. Pruss, Emily F. Smith, Tanja Bosak

Geosciences: Faculty Publications

Siliciclastic sediments of the Ediacaran Period contain exceptionally preserved fossils of macroscopic organisms, including three-dimensional casts and molds commonly found in sandstones and siltstones and some two-dimensional compressions reported in shales. The sporadic and variable associations of these exceptionally preserved macroscopic fossils with pyrite, clay minerals, and microbial fossils and textures complicate our understanding of fossilization processes. This hinders inferences about the evolutionary histories, tissue types, original morphologies, and lifestyles of the enigmatic Ediacara biota. Here, we investigate the delayed decay of scallop muscles buried in quartz sand or kaolinite for 45 days. This process occurs in the presence of …


New Source-To-Sink Approach In An Arctic Catchment Based On Hyperspectral Core-Logging (Lake Linné, Svalbard), Antonin Van Exem, Maxime Debret, Yoann Copard, Charles Verpoorter, Gregory De Wet, Nicolas Lecoq, Philippe Sorrel, Alan Werner, Steven Roof, Benoit Laignel, Michael Retelle Jan 2019

New Source-To-Sink Approach In An Arctic Catchment Based On Hyperspectral Core-Logging (Lake Linné, Svalbard), Antonin Van Exem, Maxime Debret, Yoann Copard, Charles Verpoorter, Gregory De Wet, Nicolas Lecoq, Philippe Sorrel, Alan Werner, Steven Roof, Benoit Laignel, Michael Retelle

Geosciences: Faculty Publications

No abstract provided.


Relationship Between Time Estimation, Cost Estimation, And Project Performance, Eyas Nakhleh Jan 2019

Relationship Between Time Estimation, Cost Estimation, And Project Performance, Eyas Nakhleh

Walden Dissertations and Doctoral Studies

Although the project management role is increasing, project failure rates remain high. Project time and cost are 2 project factors that can affect the performance of the projects. The purpose of this correlational study was to examine the relationship between time estimation, cost estimation, and project performance. Data collection involved a purposive sample of 67 project sponsors, managers, and coordinators in Qatar. The theoretical framework was the iron triangle, also known as the triple constraints. Participants were randomly invited to answer 18 questions using the project implementation profile instrument. A standard multiple regression analysis was used to examine the correlation …


Ecopsychology Revisited, Jorge Conesa-Sevilla Jan 2019

Ecopsychology Revisited, Jorge Conesa-Sevilla

Trade & Scholarly Monographs

Ecopsychology Revisited is a critique of and deconstructive approach to several trends termed “ecopsychology.” This work attempts to bring light to some of the misconceptions that have hardened as “ecopsychology,” as these ideas have been reinterpreted and sometimes oversimplified by the general public and some professionals outside mainstream psychology. Part of the confusion arose when “ecopsychology” became inadequately amalgamated with other ideas. Nevertheless, within the social and behavioral sciences, at least, there is great value in devising and applying evidence-based strategies that track the normative ramifications dealing with cognition, emotion and behavior, exploring how or why humans relate to natural …


Quantized Circulation In Racetrack Atomtronic Circuits At Non-Zero Temperature, Benjamin R. Eller Jan 2019

Quantized Circulation In Racetrack Atomtronic Circuits At Non-Zero Temperature, Benjamin R. Eller

College of Graduate Studies: Theses & Dissertations

We extend previous theoretical investigations of the creation of quantized circulation states by stirring Bose-Einstein condensates (BEC) confined in ``racetrack" potentials. The previous study, {\em Producing Smooth Flow in Atom Circuits by Stirring}, used the Gross-Pitaevskii equation (GPE), which is valid at $T=0$ K. Here we use a non-zero temperature model based on the Zaremba, Nikuni, Griffin (ZNG) theory to simulate stirring racetrack BECs. The two main goals of this thesis are 1) to understand the effects of temperature on the production of circulation and 2) to understand the mechanism by which the circulation is excited. We find that it …


Totally Acyclic Complexes, Holly M. Zolt Jan 2019

Totally Acyclic Complexes, Holly M. Zolt

College of Graduate Studies: Theses & 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.


Regression Tree Construction For Reinforcement Learning Problems With A General Action Space, Anthony S. Bush Jr Jan 2019

Regression Tree Construction For Reinforcement Learning Problems With A General Action Space, Anthony S. Bush Jr

College of Graduate Studies: Theses & Dissertations

Part of the implementation of Reinforcement Learning is constructing a regression of values against states and actions and using that regression model to optimize over actions for a given state. One such common regression technique is that of a decision tree; or in the case of continuous input, a regression tree. In such a case, we fix the states and optimize over actions; however, standard regression trees do not easily optimize over a subset of the input variables\cite{Card1993}. The technique we propose in this thesis is a hybrid of regression trees and kernel regression. First, a regression tree splits over …


The Relationship Between Housing Affordability And Demographic Factors: Case Study For The Atlanta Beltline, Chapman T. Lindstrom Jan 2019

The Relationship Between Housing Affordability And Demographic Factors: Case Study For The Atlanta Beltline, Chapman T. Lindstrom

College of Graduate Studies: Theses & Dissertations

Housing affordability has been a widely examined subject for populations residing in major metropolitan regions around the world. The relationship between housing affordability and the city’s demographics and its volume of urban development are important to take into consideration. In the past two decades there has been an increasing volume of literature detailing Atlanta Georgia’s large-scale redevelopment project, the Atlanta BeltLine (ABL), and its relationship with Atlanta’s Metropolitan population and housing affordability. The first objective of this paper is to study the relationship between housing affordability at two scales within the Atlanta Metropolitan Area (AMA) for both renters and homeowners. …


Data Patterns Discovery Using Unsupervised Learning, Rachel A. Lewis Jan 2019

Data Patterns Discovery Using Unsupervised Learning, Rachel A. Lewis

College of Graduate Studies: Theses & Dissertations

Self-care activities classification poses significant challenges in identifying children’s unique functional abilities and needs within the exceptional children healthcare system. The accuracy of diagnosing a child's self-care problem, such as toileting or dressing, is highly influenced by an occupational therapists’ experience and time constraints. Thus, there is a need for objective means to detect and predict in advance the self-care problems of children with physical and motor disabilities. We use clustering to discover interesting information from self-care problems, perform automatic classification of binary data, and discover outliers. The advantages are twofold: the advancement of knowledge on identifying self-care problems in …


Taking A Canon To The Adjunction Formula, Paul M. Harrelson Jan 2019

Taking A Canon To The Adjunction Formula, Paul M. Harrelson

College of Graduate Studies: Theses & Dissertations

In this paper, we show how the canonical divisor of a graph is related to the canonical divisor of its subgraph. The use of chip firing and the adjunction formula for graphs ex- plains said relation and even completes it. We go on to show the difference between the formula for full subgraphs and that of non-full subgraphs. Examples are used to simplify these results and to see the adjunction formula in action. Finally, we show that though the adjunction formula seems simple at first glance, it is somewhat complex and rather useful.


Safety Constraint Optimization Of Combination Drug Therapy In Hypertension Clinical Trials, Victor Chukwu Jan 2019

Safety Constraint Optimization Of Combination Drug Therapy In Hypertension Clinical Trials, Victor Chukwu

College of Graduate Studies: Theses & Dissertations

In Clinical Practice, combination drug therapy has become common in treating many disease conditions. The purpose of these combinations is often to ensure optimal efficacy and to reduce adverse effects that may arise from monotherapy. Clinical trials have also been conducted to ensure efficacy and safety of these combinations before they are introduced into the market. However, adverse effects still occur with combination therapies. The objective of this study is to (1) To determine a region of optimum doses of Drug A and Drug B in combination while focusing on efficacy alone (2) To determine a region of optimum doses …


Some New Generalized Distribution Via Lindley-Weibuli And Lindley-Log-Logistic Distributions With Applications, Soliu A. Raheem Jan 2019

Some New Generalized Distribution Via Lindley-Weibuli And Lindley-Log-Logistic Distributions With Applications, Soliu A. Raheem

College of Graduate Studies: Theses & Dissertations

In this thesis, new generalized distributions, namely Beta Lindley-Log-Logistic (BLLLoG) distribution, Marshall-Olkin Lindley-Weibull (MOLW) distribution, and Gamma LindleyWeibull (GLW) distribution as well as related sub-distributions are proposed. Series expansion of the densities are obtained. Statistical properties of these distributions, including hazard function, reverse hazard function, moments, reliability, quantile function, mean deviations, Bonferroni and Lorenz curves, entropy and Fisher information are derived. Method of maximum likelihood is used to estimate the parameters of the new distributions. Monte Carlo simulation is employed to examine the performance of the proposed distributions. Applications of the generalized distributions to real lifetime data are presented to …


Wetland Biogeochemical Responses To Predicted Climate Change Scenarios, Angela R. Shaffer Jan 2019

Wetland Biogeochemical Responses To Predicted Climate Change Scenarios, Angela R. Shaffer

College of Graduate Studies: Theses & Dissertations

Wetlands are one of the world's largest known carbon sinks while comprising only a small amount of the Earth's surface. However, the amount of carbon sequestered by wetlands is shrinking as droughts and human disturbance increases. Carbon in wetlands is stored through the contrast of decomposition and sedimentation of organic matter and absorption of CO2 from the atmosphere by soil microbes. Understanding how changing hydrological regimes and increased wildfires will affect wetland soil and microbial processes is important in the face of predicted climate change for future wetland conservation practices. Specifically, I seek to understand the response of southeastern …


Variable Selection In Accelerated Failure Time (Aft) Frailty Models: An Application Of Penalized Quasi-Likelihood, Sarbesh R. Pandeya Jan 2019

Variable Selection In Accelerated Failure Time (Aft) Frailty Models: An Application Of Penalized Quasi-Likelihood, Sarbesh R. Pandeya

College of Graduate Studies: Theses & Dissertations

Variable selection is one of the standard ways of selecting models in large scale datasets. It has applications in many fields of research study, especially in large multi-center clinical trials. One of the prominent methods in variable selection is the penalized likelihood, which is both consistent and efficient. However, the penalized selection is significantly challenging under the influence of random (frailty) covariates. It is even more complicated when there is involvement of censoring as it may not have a closed-form solution for the marginal log-likelihood. Therefore, we applied the penalized quasi-likelihood (PQL) approach that approximates the solution for such a …


Community-Based Climate Change Adaptation Action Plans To Support Climate-Resilient Development In The Eastern African Highlands, Tino Johansson, Emmah Owidi, Sarah Ndonye, Sarah Achola, Weyessa Garedew, Claudia Capitani Jan 2019

Community-Based Climate Change Adaptation Action Plans To Support Climate-Resilient Development In The Eastern African Highlands, Tino Johansson, Emmah Owidi, Sarah Ndonye, Sarah Achola, Weyessa Garedew, Claudia Capitani

All Peer-Reviewed Publications

Smallholder farmers in the Eastern African Highlands depend on rain-fed agriculture for their livelihoods. Climate adaptation and sustainable development goals must be targeted in an integrated way to better match farmers’ realities and address local priorities and vulnerabilities in these areas. To support climate-resilient development in the Eastern African Highlands, 224 local stakeholders were engaged in the development of community-based climate change adaptation action plans for the Jimma Highlands in Ethiopia, Taita Hills in Kenya, and Mount Kilimanjaro in Tanzania. Participatory methods, high-resolution climate projections, and the United Nations Development Programme’s (UNDP’s) guidelines were used in the design of these …


Conservation Agriculture Enhances Soil Fauna Richness And Abundance In Low Input Systems: Examples From Kenya, Fredrick Ouma Ayuke, Job Kihara, George Ayaga, Alfred N. Micheni Jan 2019

Conservation Agriculture Enhances Soil Fauna Richness And Abundance In Low Input Systems: Examples From Kenya, Fredrick Ouma Ayuke, Job Kihara, George Ayaga, Alfred N. Micheni

All Peer-Reviewed Publications

Conservation agriculture (CA) (zero tillage + organic inputs as surface residue) is believed to improve soil nutrient status, soil structure, control soil erosion, and also enhance soil fauna diversity. Despite the widespread interest in CA, empirical evidence of the benefits of CA on soil fauna diversity is limited, especially in low-input systems of sub-Saharan Africa (SSA). Consequently, the magnitude and effect by CA on soil fauna remains unquantified. The aim of this study was to evaluate the effect of CA and associated management practices on soil fauna richness and abundance. We hypothesized that CA and mixed cropping would positively influence …


Y2O3 Optical Constants Between 5 Nm And 50 Nm, Joseph B. Muhlestein, Benjamin D. Smith, Margaret Miles, Stephanie M. Thomas, Anthony Willey, David D. Allred, R. Steven Turley Jan 2019

Y2O3 Optical Constants Between 5 Nm And 50 Nm, Joseph B. Muhlestein, Benjamin D. Smith, Margaret Miles, Stephanie M. Thomas, Anthony Willey, David D. Allred, R. Steven Turley

Faculty Publications

We report optical constants of e-beam evaporated yttrium oxide Y2O3 thin films as determined from angle-dependent reflectance measurements at wavelengths from 5 to 50 nm. Samples were measured using synchrotron radiation at the Advanced Light Source. The experimental reflectance data were fit to obtain values for the index of refraction and thin film roughness. We compare our computed constants with those of previous researchers and those computed using the independent atom approximation from the CXRO website. We found that the index of refraction near 36 nm is much lower than previous data from Tomiki as reported by …


Engaging Adolescent Kyrgyzstani Efl Students In Digital Storytelling Projects About Astronomy, Nadezhda Chubko, Julia E. Morris, David H. Mckinnon, Eileen V. Slater, Geoffrey W. Lummis Jan 2019

Engaging Adolescent Kyrgyzstani Efl Students In Digital Storytelling Projects About Astronomy, Nadezhda Chubko, Julia E. Morris, David H. Mckinnon, Eileen V. Slater, Geoffrey W. Lummis

Research outputs 2014 to 2021

This research is based on the Journey through Space and Time (JTST) educational astronomy project for primary and junior high school science curricula in Australia, which seeks to improve students' astronomy content knowledge through science inquiry. The focus of the current project is on the learning needs of students for whom the language of instruction is a foreign or second language (EFL/ESL). This article reports the results of a pilot case study conducted in Bishkek, Kyrgyzstan in December 2017. The research employed a Type II Case Study design. Data were collected through video and audio recordings of classroom interactions. The …


Surficial And Deep Earth Material Prediction From Geochemical Compositions, Hassan Talebi, Ute Mueller, Raimon Tolosana-Delgado, Eric C. Grunsky, Jennifer M. Mckinley, Patrice De Caritat Jan 2019

Surficial And Deep Earth Material Prediction From Geochemical Compositions, Hassan Talebi, Ute Mueller, Raimon Tolosana-Delgado, Eric C. Grunsky, Jennifer M. Mckinley, Patrice De Caritat

Research outputs 2014 to 2021

Prediction of true classes of surficial and deep earth materials using multivariate spatial data is a common challenge for geoscience modelers. Most geological processes leave a footprint that can be explored by geochemical data analysis. These footprints are normally complex statistical and spatial patterns buried deep in the high-dimensional compositional space. This paper proposes a spatial predictive model for classification of surficial and deep earth materials derived from the geochemical composition of surface regolith. The model is based on a combination of geostatistical simulation and machine learning approaches. A random forest predictive model is trained, and features are ranked based …