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Multi-Scale Modeling Of Viscoelastic Thin-Ply Composites, Milinda Madhusanka Yapa Yapa Hamillage Jan 2019

Multi-Scale Modeling Of Viscoelastic Thin-Ply Composites, Milinda Madhusanka Yapa Yapa Hamillage

Electronic Theses and Dissertations

Thin ply composites have been under the microscope of researchers for around two decades since Kawabe introduced the thin ply technology, in the Industrial Technology Center in Fukui, Japan. With the advancement of the technological aspects of manufacturing carbon fiber composites the tow spreading has improved so much as to reduce the thickness of a conventional ply up to even six-fold. Over the years carbon fiber composites have gained interest in space structures for reinforcement purposes in antennas, as structural elements that store strain energy and support the deployment of deployable structures, and in reflector concepts. Now thin-ply composites are …

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Collaborative Artificial Intelligence Algorithms For Medical Imaging Applications, Naji Khosravan Jan 2019

Collaborative Artificial Intelligence Algorithms For Medical Imaging Applications, Naji Khosravan

Electronic Theses and Dissertations

In this dissertation, we propose novel machine learning algorithms for high-risk medical imaging applications. Specifically, we tackle current challenges in radiology screening process and introduce cutting-edge methods for image-based diagnosis, detection and segmentation. We incorporate expert knowledge through eye-tracking, making the whole process human-centered. This dissertation contributes to machine learning, computer vision, and medical imaging research by: 1) introducing a mathematical formulation of radiologists level of attention, and sparsifying their gaze data for a better extraction and comparison of search patterns. 2) proposing novel, local and global, image analysis algorithms. Imaging based diagnosis and pattern analysis are "high-risk" Artificial Intelligence …

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Stochastic Optimization And Applications With Endogenous Uncertainties Via Discrete Choice Models, Mengnan Chen Jan 2019

Stochastic Optimization And Applications With Endogenous Uncertainties Via Discrete Choice Models, Mengnan Chen

Electronic Theses and Dissertations

Stochastic optimization is an optimization method that solves stochastic problems for minimizing or maximizing an objective function when there is randomness in the optimization process. In this dissertation, various stochastic optimization problems from the areas of Manufacturing, Health care, and Information Cascade are investigated in networks systems. These stochastic optimization problems aim to make plan for using existing resources to improve production efficiency, customer satisfaction, and information influence within limitation. Since the strategies are made for future planning, there are environmental uncertainties in the network systems. Sometimes, the environment may be changed due to the action of the decision maker. …

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Approximate In-Memory Computing On Rerams, Salman Anwar Khokhar Jan 2019

Approximate In-Memory Computing On Rerams, Salman Anwar Khokhar

Electronic Theses and Dissertations

Computing systems have seen tremendous growth over the past few decades in their capabilities, efficiency, and deployment use cases. This growth has been driven by progress in lithography techniques, improvement in synthesis tools, architectures and power management. However, there is a growing disparity between computing power and the demands on modern computing systems. The standard Von-Neuman architecture has separate data storage and data processing locations. Therefore, it suffers from a memory-processor communication bottleneck, which is commonly referred to as the 'memory wall'. The relatively slower progress in memory technology compared with processing units has continued to exacerbate the memory wall …

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A Smart Uav Platform For Railroad Inspection, Ryan Debevec Jan 2019

A Smart Uav Platform For Railroad Inspection, Ryan Debevec

Electronic Theses and Dissertations

Using quadcopters for analysis of an environment has been an intriguing subject of study recently. The purpose of this work is to develop a fully autonomous UAV platform for Railroad inspection The dynamics of the quadrotor is derived using Euler's and Newton's laws and then linearized around the hover position. A PID controller is designed to control the states of the quadrotor in a manner to effectively follow a vision-based path, using the down facing camera on a Parrot Mambo quadrotor. Using computer vision the distance from the position of the quadrotor to the position of the center of the …

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

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

Electronic Theses and Dissertations

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

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Analysis, Design And Efficiency Optimization Of Power Converters For Renewable Energy Applications, Xi Chen Jan 2019

Analysis, Design And Efficiency Optimization Of Power Converters For Renewable Energy Applications, Xi Chen

Electronic Theses and Dissertations

DC-DC power converters are widely used in renewable energy-based power generation systems due to the constant demand of high-power density and high-power conversion efficiency. DC-DC converters can be classified into non-isolated and isolated topologies. For non-isolated topologies, they are typically derived from buck, boost, buck-boost or forth order (such as Cuk, Sepic and Zeta) converters and they usually have relatively higher conversion efficiency than isolated topologies. However, with the applications where the isolation is required, either these topologies should be modified, or alternative topologies are needed. Among various isolated DC-DC converters, the LLC resonant converter is an attractive selection due …

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Learning Internal State Memory Representations From Observation, Josiah Wong Jan 2019

Learning Internal State Memory Representations From Observation, Josiah Wong

Electronic Theses and Dissertations

Learning from Observation (LfO) is a machine learning paradigm that mimics how people learn in daily life: learning how to do something simply by watching someone else do it. LfO has been used in various applications, from video game agent creation to driving a car, but it has always been limited by the inability of an observer to know what a performing entity chooses to remember as they act in an environment. Various methods have either ignored the effects of memory or otherwise made simplistic assumptions about its structure. In this dissertation, we propose a new method, Memory Composition Learning, …

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Optimization Algorithms For Deep Learning Based Medical Image Segmentations, Aliasghar Mortazi Jan 2019

Optimization Algorithms For Deep Learning Based Medical Image Segmentations, Aliasghar Mortazi

Electronic Theses and Dissertations

Medical image segmentation is one of the fundamental processes to understand and assess the functionality of different organs and tissues as well as quantifying diseases and helping treatment planning. With ever increasing number of medical scans, the automated, accurate, and efficient medical image segmentation is as unmet need for improving healthcare. Recently, deep learning has emerged as one the most powerful methods for almost all image analysis tasks such as segmentation, detection, and classification and so in medical imaging. In this regard, this dissertation introduces new algorithms to perform medical image segmentation for different (a) imaging modalities, (b) number of …

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

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

Electronic Theses and Dissertations

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

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Probabilistic Spatio-Magnitude Sinkhole Hazard Analysis For East Central Flrodia, Yong Je Kim Jan 2019

Probabilistic Spatio-Magnitude Sinkhole Hazard Analysis For East Central Flrodia, Yong Je Kim

Electronic Theses and Dissertations

In Karst areas, sinkholes are a major geohazard that creates damage and economic loss to building and civil infrastructure. The main goal of the proposed study is to develop a probabilistic spatio-magnitude sinkhole susceptibility model that predicts the potential of sinkhole occurrence on a regional scale. The dissertation presents statistical techniques such as frequency ratio (FR) and logistic regression (LR), and a machine learning technique such as artificial neural network (ANN) to develop the sinkhole hazard models. The study area was limited to the East Central Floria (ECF) region. Seven hydrogeological factors were identified as key contributing factors to sinkhole …

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Automated Synthesis Of Memristor Crossbar Networks, Dwaipayan Chakraborty Jan 2019

Automated Synthesis Of Memristor Crossbar Networks, Dwaipayan Chakraborty

Electronic Theses and Dissertations

The advancement of semiconductor device technology over the past decades has enabled the design of increasingly complex electrical and computational machines. Electronic design automation (EDA) has played a significant role in the design and implementation of transistor-based machines. However, as transistors move closer toward their physical limits, the speed-up provided by Moore's law will grind to a halt. Once again, we find ourselves on the verge of a paradigm shift in the computational sciences as newer devices pave the way for novel approaches to computing. One of such devices is the memristor -- a resistor with non-volatile memory. Memristors can …

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Utilizing Edge In Iot And Video Streaming Applications To Reduce Bottlenecks In Internet Traffic, Kutalmis Akpinar Jan 2019

Utilizing Edge In Iot And Video Streaming Applications To Reduce Bottlenecks In Internet Traffic, Kutalmis Akpinar

Electronic Theses and Dissertations

There is a large increase in the surge of data over Internet due to the increasing demand on multimedia content. It is estimated that 80% of Internet traffic will be video by 2022, according to a recent study. At the same time, IoT devices on Internet will double the human population. While infrastructure standards on IoT are still nonexistent, enterprise solutions tend to encourage cloud-based solutions, causing an additional surge of data over the Internet. This study proposes solutions to bring video traffic and IoT computation back to the edges of the network, so that costly Internet infrastructure upgrades are …

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A Theoretical, Numerical, And Experimental Study Of Trapped Droplet Coalescence And Mixing, Passively And Under Electric Field, Alireza Karbalaei Baba Jan 2019

A Theoretical, Numerical, And Experimental Study Of Trapped Droplet Coalescence And Mixing, Passively And Under Electric Field, Alireza Karbalaei Baba

Electronic Theses and Dissertations

Passive and electrically active coalescence and mixing of pairs of trapped squeezed nanodroplets were studied in this work. PDMS-glass microfluidic devices were designed and fabricated using multilevel photolithography technique. Flow-focusing method was used to generate nanoliter droplets of died glycerol inside oleic acid. The effect of factors such as flow rates and their ratio, interfacial tension, and viscosities on the size and frequency of droplet generation was studied and concluded by demonstrating the capillary number effect. A passive droplet trapping technique based on minimizing the surface energy of the droplets was employed to minimize the shear flow effects and increase …

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Stragglers-Robust First-Order Distributed Optimization Algorithms Over Networks Utilizing Gradient Coding, Elie Atallah Jan 2019

Stragglers-Robust First-Order Distributed Optimization Algorithms Over Networks Utilizing Gradient Coding, Elie Atallah

Electronic Theses and Dissertations

This dissertation considers distributed algorithms for centralized and decentralized networks that solve general convex optimization problems. First, a centralized algorithm is explored for parameter server networks robust to the straggler problem. It is proved that the server nodes' estimates converge to the minimizer of the global objective function with connections vulnerable to an allowed number of stragglers. We then show that convergence is also attained in other different cases: Either by using only the received local gradients scenario or the scenario of using delayed local gradients for the non received gradients. Concurrently, the convergence rates for the above aforementioned scenarios …

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Investigation Of Coastal Vegetation Dynamics And Persistence In Response To Hydrologic And Climatic Events Using Remote Sensing, Subrina Tahsin Jan 2019

Investigation Of Coastal Vegetation Dynamics And Persistence In Response To Hydrologic And Climatic Events Using Remote Sensing, Subrina Tahsin

Electronic Theses and Dissertations

Coastal Wetlands (CW) provide numerous imperative functions and provide an economic base for human societies. Therefore, it is imperative to track and quantify both short and long-term changes in these systems. In this dissertation, CW dynamics related to hydro-meteorological signals were investigated using a series of LANDSAT-derived normalized difference vegetation index (NDVI) data and hydro-meteorological time-series data in Apalachicola Bay, Florida, from 1984 to 2015. NDVI in forested wetlands exhibited more persistence compared to that for scrub and emergent wetlands. NDVI fluctuations generally lagged temperature by approximately three months, and water level by approximately two months. This analysis provided insight …

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A Study Of Perceptions On Incident Response Exercises, Information Sharing, Situational Awareness, And Incident Response Planning In Power Grid Utilities, Joseph Garmon Jan 2019

A Study Of Perceptions On Incident Response Exercises, Information Sharing, Situational Awareness, And Incident Response Planning In Power Grid Utilities, Joseph Garmon

Electronic Theses and Dissertations

The power grid is facing increasing risks from a cybersecurity attack. Attacks that shut off electricity in Ukraine have already occurred, and successful compromises of the power grid that did not shut off electricity to customers have been privately disclosed in North America. The objective of this study is to identify how perceptions of various factors emphasized in the electric sector affect incident response planning. Methods used include a survey of 229 power grid personnel and the use of partial least squares structural equation modeling to identify causal relationships. This study reveals the relationships between perceptions by personnel responsible for …

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Integration Of Computational Fluid Dynamics And Machine Learning For Modeling Scaffold Pore Structure For Tissue Engineering, Amir Rouhollahi Jan 2019

Integration Of Computational Fluid Dynamics And Machine Learning For Modeling Scaffold Pore Structure For Tissue Engineering, Amir Rouhollahi

Electronic Theses and Dissertations

Freeze-casting is a popular method to produce biomaterial scaffolds with highly porous structures. Three approaches are developed to predict the scaffold pore structure as function of experimental conditions including mold geometry, material and thermal boundary conditions. First, a mathematical model integrating Computational Fluid Dynamics (CFD) with Population Balance Model is developed to predict average pore size (APS) of 3D porous chitosan alginate scaffolds and to assess the influence of the geometrical parameters of mold on scaffold pore structure. The model predicted the crystallization pattern and APS for scaffolds cast in different diameter molds and filled to different heights. The predicted …

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The Feminine Margin: The Re-Imagining Of One Professor's Rhetorical Pedagogy--A Curriculum Project, Camila Alvarez Jan 2019

The Feminine Margin: The Re-Imagining Of One Professor's Rhetorical Pedagogy--A Curriculum Project, Camila Alvarez

Electronic Theses and Dissertations

Writing pedagogy uses techniques that institutionalize dichotomous thinking rather than work against it. Cartesian duality has helped to create the marginalization of people, environments, and animals inherent in Western thought. Writing pedagogy based in current-traditional rhetoric uses a writing process that reinforces the hierarchical structure of Self/Other, Author/Reader, and Teacher/Student. This structure, in conjunction with capitalism, prioritizes the self and financial gain while diminishing and objectifying the other. The thought process behind the objectification and monetization of the other created the unsustainable business and life practices behind global warming, racism, sexism, and environmental destruction. A reframing of pedagogical writing practices …

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Women's Work: Materializing Feminist Thought In Lucy Lippard's C.7,500 Exhibition, Francesca Felicella Jan 2019

Women's Work: Materializing Feminist Thought In Lucy Lippard's C.7,500 Exhibition, Francesca Felicella

Honors Undergraduate Theses

This thesis aims to explore the c.7,500 exhibition curated by Lucy Lippard as a culminating point for Lippard's activism in the arts, and more specifically, women's representation in conceptualism. Understanding Lippard's political involvement within the arts and the networks established before c.7,500 further illuminates the activist approach of an all-women's art show. Throughout Lippard's career, she has advanced the exposure of women artists through her curatorial endeavors and written criticism. Her Numbers series is continuously referenced today though little documentation of each show has been easily accessible. By looking at ephemeral artifacts and artworks from c.7,500 I aim to establish …

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Culture, Power, And Control: A Discussion Of Autonomy And Responsibility, Loren A. Alonso Jan 2019

Culture, Power, And Control: A Discussion Of Autonomy And Responsibility, Loren A. Alonso

Honors Undergraduate Theses

The purpose of this thesis is to explore how power, control, autonomy, and responsibility are active participants in culture and daily human life. First, I discuss two understandings of power, structured and diffused. I examine some different techniques of power that help support and reproduce the current power systems in place and how historically, these systems have been predominantly unjust. I then discuss an alternative view of power that incorporates both structured and diffused forms of power. I explain why this new understanding of power could be more useful in actively shifting the current unjust power structures present in the …

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Draining Your Brain: The Effects Of Four Fatiguing Task Domains On Executive Function And Prefrontal Cortex, Salim A. Mouloua Jan 2019

Draining Your Brain: The Effects Of Four Fatiguing Task Domains On Executive Function And Prefrontal Cortex, Salim A. Mouloua

Honors Undergraduate Theses

The present study empirically examined the effects of four fatiguing task domains on executive function through participants' reaction time, accuracy, and brain activity in prefrontal cortex (PFC). Forty college-age participants were collected (16 males and 24 females), of which eleven were examined using a functional near-infrared spectroscopy (fNIRS) imaging system. The present study used a 4×2 mixed factorial design consisting of fatiguing task (arm contractions task, vigilance task, distance-manipulated Fitts' task, size-manipulated Fitts' task) as a between-participant variable and n-back testing period (pre-test versus post-test 3-back task) as a within-participant variable. Results indicated significant increases in 3-back performance after …

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An Exploration Of Integrating Visual Arts To Enhance Narrative Writing In The Elementary Classroom, Diana C. Herrera Jan 2019

An Exploration Of Integrating Visual Arts To Enhance Narrative Writing In The Elementary Classroom, Diana C. Herrera

Honors Undergraduate Theses

The purpose of this thesis is to integrate visual arts to enhance narrative writing. In this study I address three questions: (1) Why should educators integrate the arts in their classroom? (2) How does the content benefit the student's participation? and (3) How can we connect visual arts into narrative writing? To answer these questions, I researched several elementary teachers across the United States who have integrated the arts in their lessons. I also have researched and found multiple benefits to educators integrating the arts in their classroom. For example, a former middle school teacher used visual representation to help …

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Study On Technology And Learning, Jeremy Bramwell Jan 2019

Study On Technology And Learning, Jeremy Bramwell

Honors Undergraduate Theses

The purpose of this research thesis is to investigate technologies effects on learning. Specifically the researchers studied the usability of intelligent personal assistant-enabled devices for learning assistance. It is assumed that using technology in educational context helps both students and educators because there is a positive effect on engagement which increases learning curves. Although, this is not always the case. The present study yielded results that were not consistent with the assumption that using any type of technology as an aid for learning has a positive effect. Further research will seek to investigate other intelligent personal assistant devices for classroom …

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Disinfection By-Product Formation Potential Assessment For Central Florida Groundwater Supplies, Tulsi Shukla Jan 2019

Disinfection By-Product Formation Potential Assessment For Central Florida Groundwater Supplies, Tulsi Shukla

Electronic Theses and Dissertations

Disinfection of potable water supplies is a primary requirement of the United States' Environmental Protection Agency's (USEPA's) Safe Drinking Water Act. The use of chlorine as a disinfectant is widely accepted by water purveyors due to its effectiveness and low cost. However, chlorine reacts with natural organic matter present in water supplies to form suspected carcinogenic disinfection by-products (DBPs). In this work, the formation of the regulated chlorinated by-products total trihalomethanes (TTHMs) and haloacetic acids (HAA5) for eleven Central Florida wells has been investigated. Fluorescence, UV-254, dissolved organic carbon (DOC), specific UV absorbance (SUVA), chlorine decay, and TTHM and HAA5 …

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Fundamental Properties Of Metallic Nanolasers, William Hayenga Jan 2019

Fundamental Properties Of Metallic Nanolasers, William Hayenga

Electronic Theses and Dissertations

The last two decades have witnessed tremendous advancements in the area of nanophotonics and plasmonics, which has helped propel the development of integrated photonic sources. Of central importance to such circuits is compact, scalable, low threshold, and efficient coherent sources that can be driven at high modulation frequencies. In this regard, metallic nanolasers offer a unique platform. Their introduction has enabled confinement of light at a subwavelength scale and the ultra-small size of the modes afforded by these structures allows for cavity enhancing effects that can help facilitate thresholdless lasing and large direct modulation bandwidths. In this report, I present …

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Processing Of Advanced Infrared Materials, Daniel Mcgill Jan 2019

Processing Of Advanced Infrared Materials, Daniel Mcgill

Electronic Theses and Dissertations

Infrared transparent glassy and crystalline materials often have unique and complex processing requirements but are an important class of materials for such applications as optical windows, lenses, waveplates, polarizers and beam splitters. This thesis investigates two specific materials, one amorphous and one crystalline, that are candidates for use in the short and midwave-infrared and mid and longwave infrared, respectively. It is demonstrated that an innovative uniaxial sintering process, which uses a sacrificial pressure-transmitting medium, can be used to fully densify a 70TeO2-20WO3-10La2O3 (TWL) glass powder. The characteristics of the sintered TWL glass is compared to that of a parent glass …

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Nanoscale Functional Imaging By Tailoring Light-Matter Interaction To Explore Organic And Biological Systems, Negar Otrooshi Jan 2019

Nanoscale Functional Imaging By Tailoring Light-Matter Interaction To Explore Organic And Biological Systems, Negar Otrooshi

Electronic Theses and Dissertations

Probing molecular systems with light has been critical to deepen our understanding of life sciences. However, conventional analytical methods fail to resolve small quantities of molecules or the heterogeneity in molecules assembled into complex systems. This bottleneck is mostly attributed to light diffraction limit. In recent years, the successful implementation of new approaches to achieve sub-wavelength chemical speciation with an Atomic Force Microscope (AFM) has paved the way to a deeper understanding of the effect of local composition and structure on the functional properties of a larger scale system. The combination of infrared light, to excite the vibrational modes of …

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Spatial Models With Specific Error Structures, Nathaniel Adu Jan 2019

Spatial Models With Specific Error Structures, Nathaniel Adu

Electronic Theses and Dissertations

The purpose of this dissertation is to study the first order autoregressive model in the spatial context with specific error structures. We begin by supposing that the error structure has a long memory in both the i and the j components. Whenever the model parameters alpha and beta equal one, the limiting distribution of the sequence of normalized Fourier coefficients of the spatial process is shown to be a function of a two parameter fractional Brownian sheet. This result is used to find the limiting distribution of the periodogram ordinate of the spatial process under the null hypothesis that alpha …

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Predictors Of Hospital Quality And Efficiency, Hoda Fotovvat Jan 2019

Predictors Of Hospital Quality And Efficiency, Hoda Fotovvat

Electronic Theses and Dissertations

American hospitals have made serious efforts to implement and expand their health information technology capabilities and to integrate different specialized care or high-tech services in order to maximize the efficiency and quality of care. In providing a variety of HIT-related services, these hospitals expanded their national reputation in line with integrated care goals. As a result, hospitals are encouraged to establish effective communication channels to facilitate patient-physician sharing of the patient care experience, to enhance effective pain management, and to transform patient-centered care modalities to solidify the adequacy of patient care processes. By analyzing national data sets publicly available, this …

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