Digital Commons Network^™

Satellite Deceleration Using Gravity Assist From Asteroid, Nicolas M. Prulhiere

Doctoral Dissertations and Master's Theses

Satellites have used gravity assists to increase their speed when exploring the solar system. This same maneuver can be done but with the objective to slow down the satellites. This has been theorized to slow down asteroids using the moon to capture them in earth’s orbit. My goal is to determine if asteroids can be used to provide a change in speed great enough to the point that after multiple of these maneuvers the satellite can come to a stop. By being able to slow down and stop a satellite without having to use thrusters will allow the mass allocated …

High Fidelity Studies In Closed-Loop Control Of Unsteady Aerodynamics, Miriam Theobald-Deschine

Doctoral Dissertations and Master's Theses

We implement and explore the success of a nonlinear, closed loop flow control strategy based on POD-ROM focusing on boundary-layer transitional flow in high-fidelity computational studies involving FDL3DI ILES code. Controlling the boundary-layer transition from laminar to turbulent allows the laminar boundary-layer to be lengthened, decreasing skin-friction drag on an airfoil. Analyses are conducted on a flat plate with an elliptical leading edge, later to be implemented in future studies with real airfoil geometry. The feedback control design employs strategically placed synthetic-jet micro actuators and pressure sensors. The efficiency of the closed-loop flow control strategies is examined in comparison with …

The Effect Of Part Curvature On The Formation Of Residual Stresses In Carbon Fiber Prepreg Laminates, Bradley Rogan

Doctoral Dissertations and Master's Theses

The formation of residual stresses during the processing of composite parts can lead to undesired defects such as delamination which can reduce the overall strength of a completed component. Furthermore, the addition of curvature to the part geometry tends to result in wrinkle formation which leads to stress concentrations developing throughout the curing process in the areas near these wrinkles. In this work, Digital Image Correlation (DIC) will be used to monitor the development of stresses throughout the cure cycle of carbon fiber prepreg in several different lay-ups and across tool plates with varying curvatures to determine what effect the …

Crisis Communication And Furloughed Hotel Frontline Employees’ Intention To Stay: The Role Of Perceived Organizational Support, Job Insecurity, And Job Affect, Tabitha A. Chapital

LSU New Orleans Theses and Dissertations

This study investigated furloughed hotel employee’s intention to stay (ITS), with their hotel and hotel industry, based upon the impact of crisis communication strategy, perceived organizational support (POS), job insecurity, and job affect following a crisis. A 2 (crisis communication strategy: apology vs. excuse) × 2 (POS: high vs. low) between subjects, factorial design was employed. The study found that apology strategy and high POS result in lower job insecurity among furloughed hotel employees. A negative correlation was also found between job insecurity and ITS with the hotel industry. These findings may support practical and theoretical implications for hoteliers, specifically …

Ecological Factors Influencing Population Dynamics Of The Mississippi Sandhill Crane, Grus Canadensis Pulla, Henry W. Woolley

LSU New Orleans Theses and Dissertations

My dissertation encompasses three studies involving ecological factors influencing the Mississippi sandhill crane (Grus canadensis pulla) population at Mississippi Sandhill National Wildlife Refuge. To examine influences on the historical population I studied trends in nesting, number of chicks fledged annually, and their environmental and biotic drivers during 1991-2018. I expected precipitation to be positively associated with population measures and drought, extreme heat, and predation to be inversely related to population measures. To examine the influence of current habitat food production on the crane population I quantified measures of production in 2018 and 2019 and their relationship to time …

A Gis-Swmm System To Evaluate Low Impact Development (Lid) Feature Effectiveness On Uno's Campus, Demetria C. Christo

LSU New Orleans Theses and Dissertations

The EPA’s Storm Water Management Model (SWMM) includes the ability to model low impact development (LID) systems involving various types of green infrastructure (GI) for stormwater detention and infiltration.

The SWMM model requires hydrologic attribute inputs for individual subcatchments, including percent impervious surfaces, surface roughness, depression storage, and curve number. These SWMM attributes can be more accurately, consistently, and efficiently be defined in GIS by calculating the subcatchment area-weighted attribute values and importing them to SWMM. Thus, GIS becomes a valuable pre-processing input tool for SWMM-LID modeling.

The three objectives of this thesis are to 1) use GIS geoprocessing tools …

Homeless Voices Across The Nation: How Government Assistance Is Perceived To Support The Homeless Community, Chelsea Helena-Marie Nelson

LSU New Orleans Theses and Dissertations

Abstract

Six subtopics are found throughout homeless-related literature including definitions of homelessness, mental health, substance abuse, policy, housing models, and COVID-19. Through conduction of 323 homeless lived experience surveys across 15 diverse cities in the United States, this research has found assumptions and conclusions between firsthand perspective and literature’s subtopics. A major gap in literature exists with the inclusion of lived experience, as this was routinely an emphasized response from the homeless population themselves. Alternate needs and solutions were proposed from the participants, which found general similarities to the subtopics and included significance of perceived apathy from politicians towards the …

Effects Of Biological Cohesion On Wave Ripple Dynamics, Malcolm F. Cross

LSU New Orleans Theses and Dissertations

In coastal environments, wave-generated oscillatory flow in the bottom boundary layer mobilizes sediment resulting in bedform generation and evolution. The presence of bedforms on the seafloor affects sediment transport, wave attenuation, and acoustic scattering. Many studies have examined the dynamics of sediment transport and the development of bedforms on the seafloor due to the interaction of waves and currents. However, these studies have relied heavily on laboratory experiments undertaken using sands with no biological influence. This research aims to understand the effects of increased cohesion within the sediment particles resulting from biological influences (e.g., extracellular polymeric substances (EPS)) on the …

Fast & Efficient Simulation For Long Polymeric Chains, Naeyma N. Islam

LSU New Orleans Theses and Dissertations

No abstract provided.

Effect Of Blue Light On Sleep & Delirium In The Intensive Care Unit, Hunter Montgomery

MSN Capstone Projects

Intensive care units (ICU) across the country are plagued with a silent morbidity that increases monetary costs, patient stay, and nursing retention known as delirium. Delirium can drive up all three of these factors creating an unnecessary burden on hospital and community resources. In response to the silent crisis, a delirium prevention bundle was created to alleviate the burdens that ICU delirium can put on a hospital.

Reviewing implementation strategies showed that employees needed extensive training on recognizing the different types of delirium including hyperactive, mixed, and hypoactive delirium. It was determined that for the delirium bundle to be successful …

Medication Reconciliation In The Elderly, Tina L. Coen

MSN Capstone Projects

Medication reconciliation is a practice that is underutilized in hospitals and primary care settings, and as a result the geriatric population is experiencing frequent ER visits and hospital readmission's. The geriatric population is subject to injury due to medication errors more than any other group. Medication reconciliation is an important part of safely caring for the geriatric population and can decrease the number of inappropriate medications that are prescribed. (Moro, 2016)

Hourly Rounding To Reduce Patient Falls - A Quality Improvement Project, Shelley L. Lloyd

MSN Capstone Projects

Patient falls are devastating. They can result in injury and even death. They also result in extra costs for the patient as well as they facility. Hourly rounding is a simple process that can help reduce the number of patient falls within an acute care facility. Purposeful hourly rounding will help meet the needs of the patient as well as allow the staff member to asses the environment for safety issues. Rounding should happen every hour during the day and every two hours at night. During these rounds, staff will ask the patient about pain, bathroom needs, comfort, peacefulness of …

A Method For Visualizing Water Flow Through Modified Root Zones, Dallas M. Williams

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

As the number of impervious surfaces in urban environments increases, the ability of modified root zones to infiltrate water is becoming more important. Current methods of tracing water flow through soil profiles include excavating large pits in situ or analyzing soil cores in the laboratory with computed tomography or magnetic resonance imaging. While useful, these methods may not be suitable for urban settings or practical in every laboratory. We propose a new method that is less invasive, does not require extensive technical equipment and can reliably trace water movement through the soil profile in order to calculate flow rate based …

Age And Roles On The Family Farm, Cassie Chambers

Humboldt Journal of Social Relations

Age is a factor that has been analyzed in the workforce for quite some time now. The aging process is universal and found in daily lives throughout the work force or labor market, but some factors of age are different in the agriculture industry. This paper aims to acknowledge and explore the aging process specifically found in the agriculture industry. The key concepts of this paper have been broken into four different topics. These topics include youth roles on the farm, mid-adult roles on the farm, older adult roles on the farm, and public policy implications dealing with the agriculture …

The Role Of Youth Characteristics, Home Ecology, And Child Maltreatment In The Severity Of Problematic Sexual Behaviors And Conduct Problems, Ariel K. Berman

Dissertations

A multitude of individual, familial, and environmental variables have previously been identified as contributing to the development of problematic sexual behaviors (PSB) and general conduct problems (CP) in youth. The majority of these studies have focused either on individual youth characteristics or parenting behaviors such as child maltreatment. Although researchers examining contributions to PSB and CP generally acknowledge the importance of the impact of the home environment on youth behavior, few researchers have included family characteristics of both parents and siblings in their analyses. Additionally, some factors that have been identified as having great importance in general juvenile delinquency, such …

How Long-Term, Non-Monogamous Romantic Relationships Maintain Sexual Satisfaction, Anna Kessler

UNLV Theses, Dissertations, Professional Papers, and Capstones

Eroticism is an important element of couple's relationships. Sexual intimacy has the power to bring couples closer together, as higher levels of sexual intimacy results in higher relationship satisfaction, or hinder relationships if either or both partners aren’t sexually satisfied in their relationship. The current study’s purpose is to understand how long-term, non-monogamous relationships have successfully maintained “eroticism” throughout the course of their relationship. In this study, 24 couples who are in a committed, romantic relationship of at least 7 years were interviewed. The interviews were conducted individually over a video call platform, and each was completed withing approximately 60 …

How Covid-19 Has Impacted Romantic Relationship Dynamics, Alexandria Jayci Lake

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to provide an exploration of impacts to romantic relationship dynamics attributed the COVID-19 pandemic. Though many attributes of COVID-19 classify it as a distinct, unique event in its own right, a literature review of past global health events and economic crises provided a foundational reference point from which to compare it to. Twelve participants who were in relationships with another person for at least four years at the time were interviewed, six of which who were parented individuals and six of which who had no children, to discover how COVID-19-related changes developed over the …

The Influences Of Medicaid On Mental Health Practitioners, Matthew Mohan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Medicaid is the largest publicly funded health insurance program which influences the mental health practitioners’ treatment of low income individuals (Altman & Frist, 2015; Rowland et al., 2003). To understand how Medicaid influences mental health practitioners, this study utilizes institutional theory by using the five propositions from Lammers and Barbour (2006) to analyze how Medicaid’s communicative practices influence mental health practitioners who treat those who are in poverty. Semi-structured interviews were conducted with 10 mental healthcare practitioners who accepted Medicaid: two psychologists, five social workers, one psychiatrist, and two psychiatric nurse practitioners. The results demonstrate how mental health practitioners respond …

A Discipline In Search Of A Voice: A Corpus Linguistic Study Of Evaluation Scholarly Literature, Aaron Wilson Kates

Dissertations

Linguists use the concept of discourse community (DC) to describe the speech of groups of people associated by some extrinsic purpose or interest (Swales, 1990). One defining feature of a DC is a shared lexicon. Scriven (1994), in his discussion of evaluation as a discipline, addresses the need for evaluation to have a “core subject” which would then allow, among other things, the development of “concepts and language to deal with core problems,” while noting that there exists a definite lack of clarity of language among evaluators (p. 147). Christie and Rose (2003) suggest that the lack of clarification around …

Distribution Of Visitor Use Management Research In Us Wilderness From 2000 To 2020: A Scoping Review, William L. Rice, Christopher A. Armatas, Jennifer M. Thomsen, Jaclyn R. Rushing

Society and Conservation Faculty Publications

Visitor use in wilderness has grown over the past several decades, along with research focused on visitor use management (VUM) in congressionally designated wilderness. This scoping review of research published between 2000 and 2020 explores the distribution and representativeness of wilderness VUM research within the context of (a) the federal land management agencies administering wilderness and (b) the geographic distribution of research. Findings indicate wilderness administered by the Bureau of Land Management and US Fish and Wildlife Service were disproportionately understudied compared to both the total acreage of wilderness and number of wilderness areas administered by the US Forest Service …

Verification Of A Mobile Psychoacoustic Test System, Jordana C. Soares, Sangamanatha Veeranna, Vijay Parsa, Chris Allan, Winnie Ly, Minh Duong, Paula Folkeard, Sheila Moodie, Prudence Allen

Faculty Publications

Many hearing difficulties can be explained as a loss of audibility, a problem easily detected and treated using standard audiological procedures. Yet, hearing can be much poorer (or more impaired) than audibility predicts because of deficits in the suprathreshold mechanisms that encode the rapidly changing, spectral, temporal, and binaural aspects of the sound. The ability to evaluate these mechanisms requires well-defined stimuli and strict adherence to rigorous psychometric principles. This project reports on the comparison between a laboratory-based and a mobile system’s results for psychoacoustic assessment in adult listeners with normal hearing. A description of both systems employed is provided. …

A Molecular Design Approach Towards Elastic And Multifunctional Polymer Electronics, Yu Zheng, Zhiao Yu, Song Zhang, Xian Kong, Wesley Michaels, Weichen Wang, Gan Chen, Deyu Liu, Jian Cheng Lai, Nathaniel Prine, Weimin Zhang, Shayla Nikzad, Christopher B. Cooper, Donglai Zhong, Jaewan Mun, Zhitao Zhang, Jiheong Kang, Jeffrey B.H. Tok, Iain Mcculloch, Jian Qin, Xiaodan Gu, Zhenan Bao

Faculty Publications

Next-generation wearable electronics require enhanced mechanical robustness and device complexity. Besides previously reported softness and stretchability, desired merits for practical use include elasticity, solvent resistance, facile patternability and high charge carrier mobility. Here, we show a molecular design concept that simultaneously achieves all these targeted properties in both polymeric semiconductors and dielectrics, without compromising electrical performance. This is enabled by covalently-embedded in-situ rubber matrix (iRUM) formation through good mixing of iRUM precursors with polymer electronic materials, and finely-controlled composite film morphology built on azide crosslinking chemistry which leverages different reactivities with C–H and C=C bonds. The high covalent crosslinking density …

Approaching Disorder-Tolerant Semiconducting Polymers, Xinwen Yan, Miao Xiong, Xin Yu Deng, Kai Kai Liu, Jia Tong Li, Xue Qing Wang, Song Zhang, Nathaniel Prine, Zhuoqiong Zhang, Wanying Huang, Yishan Wang, Jie Yu Wang, Xiaodan Gu, Shu Kong So, Jia Zhu, Ting Lei

Faculty Publications

Doping has been widely used to control the charge carrier concentration in organic semiconductors. However, in conjugated polymers, n-doping is often limited by the tradeoff between doping efficiency and charge carrier mobilities, since dopants often randomly distribute within polymers, leading to significant structural and energetic disorder. Here, we screen a large number of polymer building block combinations and explore the possibility of designing n-type conjugated polymers with good tolerance to dopant-induced disorder. We show that a carefully designed conjugated polymer with a single dominant planar backbone conformation, high torsional barrier at each dihedral angle, and zigzag backbone curvature is highly …

Ultra-Conformal Skin Electrodes With Synergistically Enhanced Conductivity For Long-Time And Low-Motion Artifact Epidermal Electrophysiology, Yan Zhao, Song Zhang, Tianhao Yu, Yan Zhang, Guo Ye, Han Cui, Chengzhi He, Wenchao Jiang, Yu Zhai, Chunming Lu, Xiaodan Gu, Nan Liu

Faculty Publications

Accurate and imperceptible monitoring of electrophysiological signals is of primary importance for wearable healthcare. Stiff and bulky pregelled electrodes are now commonly used in clinical diagnosis, causing severe discomfort to users for long-time using as well as artifact signals in motion. Here, we report a ~100 nm ultra-thin dry epidermal electrode that is able to conformably adhere to skin and accurately measure electrophysiological signals. It showed low sheet resistance (~24 Ω/sq, 4142 S/cm), high transparency, and mechano-electrical stability. The enhanced optoelectronic performance was due to the synergistic effect between graphene and poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), which induced a high …

Metacognition, Social Cognition, And Mentalizing In Psychosis: Are These Distinct Constructs When It Comes To Subjective Experience Or Are We Just Splitting Hairs?, P. H. Lysaker, S. Cheli, G. Dimaggio, B. Buck, K. A. Bonfils, K. Huling, C. Wiesepape, J. T. Lysaker

Faculty Publications

Research using the integrated model of metacognition has suggested that the construct of metacognition could quantify the spectrum of activities that, if impaired, might cause many of the subjective disturbances found in psychosis. Research on social cognition and mentalizing in psychosis, however, has also pointed to underlying deficits in how persons make sense of their experience of themselves and others. To explore the question of whether metacognitive research in psychosis offers unique insight in the midst of these other two emerging fields, we have offered a review of the constructs and research from each field. Following that summary, we discuss …

Label-Free Characterization Of Organic Nanocarriers Reveals Persistent Single Molecule Cores For Hydrocarbon Sequestration, Terry Mcafee, Thomas Ferron, Isvar A. Cordova, Phillip D. Pickett, Charles L. Mccormick, Cheng Wang, Brian A. Collins

Faculty Publications

Self-assembled molecular nanostructures embody an enormous potential for new technologies, therapeutics, and understanding of molecular biofunctions. Their structure and function are dependent on local environments, necessitating in-situ/operando investigations for the biggest leaps in discovery and design. However, the most advanced of such investigations involve laborious labeling methods that can disrupt behavior or are not fast enough to capture stimuli-responsive phenomena. We utilize X-rays resonant with molecular bonds to demonstrate an in-situ nanoprobe that eliminates the need for labels and enables data collection times within seconds. Our analytical spectral model quantifies the structure, molecular composition, and dynamics of a copolymer micelle …

Nutrient Content And Stoichiometry Of Pelagic Sargassum Reflects Increasing Nitrogen Availability In The Atlantic Basin, B. E. Lapointe, R. A. Brewton, L. W. Herren, M. Wang, C. Hu, D. J. Mcgillicuddy, S. Lindell, F. J. Hernandez, P. L. Morton

Faculty Publications

The pelagic brown macroalgae Sargassum spp. have grown for centuries in oligotrophic waters of the North Atlantic Ocean supported by natural nutrient sources, such as excretions from associated fishes and invertebrates, upwelling, and N₂ fixation. Using a unique historical baseline, we show that since the 1980s the tissue %N of Sargassum spp. has increased by 35%, while %P has decreased by 44%, resulting in a 111% increase in the N:P ratio (13:1 to 28:1) and increased P limitation. The highest %N and δ¹⁵N values occurred in coastal waters influenced by N-rich terrestrial runoff, while lower C:N and …

Accurate Diagnosis Of Colorectal Cancer Based On Histopathology Images Using Artificial Intelligence, K. S. Wang, G. Yu, C. Xu, X. H. Meng, J. Zhou, C. Zheng, Z. Deng, L. Shang, R. Liu, S. Su, X. Zhou, Q. Li, J. Li, J. Wang, K. Ma, J. Qi, Z. Hu, P. Tang, J. Deng, X. Qiu, B. Y. Li, W. D. Shen, R. P. Quan, J. T. Yang, L. Y. Huang, Y. Xiao, Z. C. Yang, Z. Li, S. C. Wang, H. Ren, C. Liang, W. Guo, Y. Li, H. Xiao, Y. Gu, J.P. Yun, D. Huang, Z. Song, X. Fan, L. Chen, X. Yan, Z. Li, Z.C. Huang, J. Huang, J. Luttrell, Chaoyang Zhang, W. Zhou, K. Zhang, C. Yi, C. Wu, H. Shen, Y.P. Wang, H.M. Xiao, H.W. Deng

Faculty Publications

Background: Accurate and robust pathological image analysis for colorectal cancer (CRC) diagnosis is time-consuming and knowledge-intensive, but is essential for CRC patients’ treatment. The current heavy workload of pathologists in clinics/hospitals may easily lead to unconscious misdiagnosis of CRC based on daily image analyses.

Methods: Based on a state-of-the-art transfer-learned deep convolutional neural network in artificial intelligence (AI), we proposed a novel patch aggregation strategy for clinic CRC diagnosis using weakly labeled pathological whole-slide image (WSI) patches. This approach was trained and validated using an unprecedented and enormously large number of 170,099 patches, > 14,680 WSIs, from > 9631 subjects …

The Coupling And Competition Of Crystallization And Phase Separation, Correlating Thermodynamics And Kinetics In Opv Morphology And Performances, Zaiyu Wang, Ke Gao, Yuanyuan Kan, Ming Zhang, Chaoqun Qiu, Lei Zhu, Zhe Zhao, Xiaobin Peng, Wei Feng, Zhiyuan Qian, Xiaodan Gu, Alex K.Y. Jen, Ben Zhong Tang, Yong Cao, Yongming Zhang, Feng Liu

Faculty Publications

The active layer morphology transition of organic photovoltaics under non-equilibrium conditions are of vital importance in determining the device power conversion efficiency and stability; however, a general and unified picture on this issue has not been well addressed. Using combined in situ and ex situ morphology characterizations, morphological parameters relating to kinetics and thermodynamics of morphology evolution are extracted and studied in model systems under thermal annealing. The coupling and competition of crystallization and demixing are found to be critical in morphology evolution, phase purification and interfacial orientation. A unified model summarizing different phase diagrams and all possible kinetic routes …

Developing Implementable Policies Targeting Sustainable Building Construction Through International Policy Diffusion, Melisa Ciara Hancock

Boise State University Theses and Dissertations

The buildings and construction sector is one of the biggest sources of greenhouse gas emissions and contributes to vast list of negative impacts humans have on the environment through material production, natural resource usage, and waste. While many organizations like the United Nations (UN), OECD (Organization for Economic Co-operation and Development), and Architecture 2030 have been advocating for a shift to sustainability within the sector for decades, there is still a major disconnect between countries that have and haven’t implemented sustainability into all practices. This research focuses on analyzing the content of national building codes for their level of sustainability …